UHR — NAEOTOM Connect https://connect.siemens-healthineers.com/zh/ Sun, 25 Oct 2026 04:14:50 +0000 zh UHR — NAEOTOM Connect (2026) Huijberts | Visualisation of lenticulostriate arteries using PCCT https://connect.siemens-healthineers.com/zh/discussion/589/2026-huijberts-visualisation-of-lenticulostriate-arteries-using-pcct Wed, 21 Oct 2026 11:44:48 +0000 Publication protocols Daniel Stromer 589@/zh/discussions

In this retrospective cohort of 159 patients with subarachnoid haemorrhage, UHR PCCT substantially improved lenticulostriate artery (LSA) visualization compared with conventional EID-CTA. For branches arising >5 mm from the MCA origin, PCCT detection approached DSA—for example, 93% vs 85% for observer 1 in the left hemisphere (p = 0.62)—while EID-CTA detected only 49% in the unpaired comparison.

PCCT remained inferior to DSA for depicting the full distal extent of larger LSA branches. Median LSA length >5 mm from the MCA origin was 23 mm on PCCT vs 40 mm on DSA for observer 1, whereas PCCT nevertheless showed significantly longer measurable branches than EID-CTA (23 vs 15 mm, p < 0.001).

The main technical trade-off was dose: the optimized 90-kVp, 0.2-mm UHR PCCT protocol achieved markedly better small-vessel visualization, but CTDIvol ranged 17–27 mGy, above the reported EID-CTA ranges. Thus, PCCT appears promising as a non-invasive alternative for LSA assessment, but DSA remains superior for the most distal branches and prospective clinical validation is needed.

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SUPPLEMENTAL APPENDIX

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Figure 2. LSA visualisation on DSA, EID-CTA and PCD-CT Note: (A) Rotational angiography; (B) Conventional anterior-to-posterior imaging; (C) 3D angiography cone beam CT (D) Second-generation dual source EID-CTA [flash]; (E) Third-generation dual source EID-CTA [force]; (F) PCD-CT.

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Table S1: Detailed information on employed CTA imaging protocols

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Intracranial CTA / lenticulostriate arteries

Acquisition mode

UHR

Tube voltage [kVp]

90

Tube current-time product [mAs]

250–330

CTDIvol [mGy]

17–27

Rotation time [s]

0.25

Pitch

0.4

Detector slice collimation

120 × 0.2 mm

Reconstruction slice thickness [mm]

0.2

Kernels

Hv40, Hv72, Bv40

Spectral reconstruction

Polychromatic T3D

Image analysis

Coronal MIP with reader-adjustable slab thickness, angulation, and window/level

LSA assessment

Presence, number, length, and subjective image quality

Reference standard

DSA, including rotational angiography, AP angiography, and/or 3D cone-beam angiography

Key Results

Parameter

Main finding

Study population

159 patients

PCCT vs DSA detection, LSA >5 mm

Observer 1: 93% vs 85%, p = 0.62; Observer 2: 78% vs 78%, p = 1.00

PCCT vs EID-CTA detection, LSA >5 mm

Observer 1: 93% vs 49%, p < 0.001; Observer 2: 79% vs 55%, p = 0.03

LSA length >5 mm, PCCT vs DSA

Observer 1: 23 [21–29] vs 40 [34–49] mm, p < 0.001

LSA length >5 mm, PCCT vs EID-CTA

Observer 1: 23 [19–28] vs 15 [9–22] mm, p < 0.001

Inter-reader reliability

Generally poor-to-moderate; PCCT left-hemisphere length ICC 0.610

Source:
Huijberts I, Wagemans BAJM, Pinckaers FME, Robbe MMQ, van Zwam WH, van Oostenbrugge RJ, Postma AA. Visualisation of lenticulostriate arteries using photon counting detector CT angiography: A retrospective cohort study. European Journal of Radiology. 2026;195:112618. doi:10.1016/j.ejrad.2025.112618.

]]> (2026) Volovici | UHR PCCT pure-lumen imaging for neurosurgical navigation https://connect.siemens-healthineers.com/zh/discussion/552/2026-volovici-uhr-pcct-pure-lumen-imaging-for-neurosurgical-navigation Sun, 11 Oct 2026 09:35:12 +0000 Publication protocols Daniel Stromer 552@/zh/discussions

In this selected pilot cohort of 20 complex neurosurgical cases, UHR PCCT provided additional anatomical information beyond conventional MRI/CT, particularly for arterial anatomy (11/20, 55%), tumor vascular supply (7/20, 35%), venous anatomy (6/20, 30%), and skull-base/orbital/osseous involvement (8/20, 40%). The greatest apparent benefit was in complex skull-base meningiomas and vascular lesions.

The technical advantage was the combination of 0.2-mm-class UHR vascular imaging, bone-subtracted pure-lumen reconstructions, spectral imaging, and simultaneous osseous depiction. This allowed visualization of small-caliber vessels, tumor feeders, perforators, venous drainage, vessel encasement/displacement, and hyperostotic or transosseous tumor extension relevant to surgical navigation.

These results are explicitly hypothesis-generating rather than evidence of clinical superiority. The cohort was strongly selected—19 of 45 PCCT examinations were excluded because they showed no additional findings—and comparisons were unblinded and not validated systematically against operative or angiographic reference standards. The proposed role is therefore PCCT complementary to MRI, rather than replacing MRI for lesion characterization.

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Fig. 3. Case #8. Spheno-orbital meningioma. Coronal T1w post-contrast MRI (A), post-contrast CT (B), and pure-lumen reconstruction (C) delineate the lesion, demonstrating clearer differentiation between tumor parenchyma and vascular structures. Sagittal MIP CTA (D) shows extensive intratumoral radial vascularity and underlying hyperostosis (*). 3D reconstructions show tumor vascularization (E) and a hypertrophic middle meningeal artery (F: arrow).

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Figure 4. Case #13. Left fronto-parietal (precentral gyrus) AVM with a large (>4 cm) nidus. DSA (A) demonstrates the AVM nidus with arterial supply from the left ACA and MCA, and superficial venous drainage without deep venous outflow. A 3D reconstruction of contrast-enhanced PCCT (B) depicts the AVM in relation to the surrounding vasculature. Coronal 0.2 mm PCCT reconstruction (C) provides high-resolution and highly detailed delineation of the nidus and adjacent vessels, while a matched 1.6 mm post-contrast MRI reconstruction (D) through the same plane provides cross-modality correlation.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Intracranial / preoperative neuronavigation

Acquisition

UHR PCCT angiography ± venography

Scan mode

Helical, single-tube acquisition

Tube voltage

120 kV

IQ level

90–145

Dose modulation

Automatic tube-current modulation, CARE Dose4D

CTDIvol [mGy]

18.2 mean

DLP [mGy·cm]

352 mean

Rotation time [s]

0.25

Pitch

0.55–0.80

Detector collimation

0.2 mm (total collimation 24 mm)

Slice thickness

0.2–0.4 mm

Kernels

Hv, Hr, Qr (high)

Iterative reconstruction

Q3–Q4

VMI

Low-noise/UHR series at 55 keV; spectral display primarily at 40 keV

Spectral reconstruction

Bone-subtracted angiographic pure-lumen images

Contrast

Iodixanol 320 mg I/mL

Contrast volume

80 mL

Injection rate

5.0 mL/s

Saline flush

40 mL

Bolus triggering

Bolus tracking

Key Results

Parameter

Main finding

Study cohort

20 selected cases from 45 preoperative UHR PCCT examinations; 12/20 meningiomas

Additional arterial information

11/20 (55%), including perforators in 2/20 (10%)

Additional tumor vascular supply

7/20 (35%)

Additional venous information

6/20 (30%)

Additional skull-base/orbital/osseous information

8/20 (40%)

Radiation dose

PCCT CTA: CTDIvol 18.2 mGy, DLP 352 mGy·cm vs institutional standard neuronavigation CT: 50.6 mGy, 1046 mGy·cm

Source:
Volovici V, Sadigh Y, Dijkshoorn M, van der Eerden A, Gahrmann R, et al. Pre-operative visualization of cerebral vasculature using photon-counting CT ultra-high resolution pure lumen imaging. Brain and Spine. 2026;107451. doi:10.1016/j.bas.2026.107451.

]]> A massive primary cerebral ALK-positive anaplastic large cell lymphoma in an adolescent https://connect.siemens-healthineers.com/zh/discussion/178/a-massive-primary-cerebral-alk-positive-anaplastic-large-cell-lymphoma-in-an-adolescent Wed, 31 Dec 2025 08:54:00 +0000 Case reports Daniel Stromer 178@/zh/discussions

Xiangyu Liu, RT*; Jiaxu Wei, RT*; Xi Zhao, MD**; Ji Wang, RT*

* Department of Radiology, Shanghai Jiao Tong University School of Medicine Affiliated Renji Hospital, Shanghai, P. R. China** Siemens Healthineers, China

2025-07-02

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History

A 15-year-old male patient, complaining of a growing lump on the right of his forehead over the past 20 days, came to the hospital for a check-up. He was otherwise asymptomatic. His medical history was unremarkable. Physical examination revealed no abnormalities. A contrast-enhanced CT scan was performed with a dual source photon-counting CT (PCCT), NAEOTOM Alpha, using an ultra-high resolution (UHR) scan mode, for assessment.

Diagnosis

CT images showed an expansive frontotemporal mass, measuring 66 mm x 65 mm in size, protruding into the right orbit, the right frontal sinus and subcutaneously. It was also compressing the right lateral ventricle, shifting the cerebral midline and both the anterior cerebral arteries (ACA) leftwards, and the right middle cerebral artery (MCA) backwards, and causing bone erosion of the squamous part of the right temporal bone and posterolateral orbital wall. The mass, homogeneous and slightly hyperdense in the virtual non-contrast (VNC) images, showed uniformed contrast enhancement in the virtual monoenergetic images (VMI) displayed at 55 keV, as well as in the iodine maps, with multiple hyperdense foci inside. Hypodense areas around the mass were seen, suggesting edema. The intraorbital segment of the optic nerve was compressed, however, not invaded. CT findings suspected a meningioma. A MRI was suggested for further assessment, also suspecting a meningioma. A lymphoma was considered in the differential diagnosis, however, there were no typical signs in either CT or MRI.

Subsequently, the patient underwent surgical removal of the mass. Histologic and immunophenotypic findings revealed an anaplastic large cell lymphoma (ALCL), anaplasticlymphoma-kinase (ALK) positive. The patient recovered well and was discharged two weeks later with scheduled outpatient follow-ups.

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Fig. 1: Coronal view of a 0.2 mm UHR image (Fig. 1a) shows bone erosion (arrows) of the squamous part of the right temporal bone and the posterolateral orbital wall. 1 mm slices with spectral information are reconstructed from the UHR data to reformat coronal views of a VMI displayed at 55 keV (Fig. 1b), a VNC (Fig. 1c), and an iodine map (Fig. 1d). These images show an expansive frontotemporal mass, homogeneous and slightly hyperdense in VNC, uniformly contrast enhanced in VMI and iodine images, with multiple hyperdense foci inside, protruding into the right orbit and shifting the cerebral midline to the left.

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Fig. 2: Oblique MPR images show the tumor protruding into the right frontal sinus and the right orbit, compressing the intraorbital segment of the optic nerve. The fine separation (arrows) between the tumor edge and optic nerve is better seen in 0.2 mm UHR image (Fig. 2a) and in VMI displayed at 55 keV (Fig. 2b), in comparison to a VMI displayed at 70 keV (Fig. 2c) corresponding to an image acquired at 120 kV in standard scan.

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Fig. 3: cVRT images, reconstructed using 0.2 mm UHR slices, show bone erosion of the squamous part of the right temporal bone and the posterolateral orbital wall (Fig. 3a, arrows), the extracranial (Fig. 3b) and intracranial (Fig. 3c) feeding arteries (arrowheads) to the tumor in detail. Both ACA are shifted leftwards and the right MCA is shifted backwards.

Comments

Primary ALCLs, occurring in the central nervous system (CNS), are extremely rare. They tend to occur in children and young adults, predominantly male patients, with a prognosis correlated with ALK positivity. A favorable course has been exhibited in younger patients with ALK-positive ALCL. As the imaging characteristics are atypical, diagnosis and differential diagnosis are difficult with traditional imaging alone, especially when the tumor is massive and invasive, such as in this case.

A unique combination of high spatial resolution and spectral information, provided by PCCT, is helpful in visualizing the detailed cerebral, vascular and bony structures using the image data acquired from one UHR scan. The VMI of the cerebrum are routinely set to be displayed at a low keV level (55 keV) allowing for enhanced contrast. VNC images can be displayed with one mouse click, without having to perform a native scan. In daily practice, these different image types – VMI, VNC and iodine – can be interactively toggled, using Interactive Spectral Imaging (ISI) technique available in image reading. In UHR mode, small sub-pixels are defined by electric fields, instead of physical separations, and are read out separately to increase the spatial resolution. This approach improves the geometrical dose efficiency of the detector to enable UHR imaging without radiation dose penalty. In addition, PCCT optimizes the contrast-to-noise ratio (CNR) with a combination of missing down-weighting of the lower energy X-ray photons, the absence of the electronic noise and the inherent spectral information. A practical example is that the UHR images, acquired and reconstructed at 0.2 mm slice width, can be used to create lifelike three-dimensional images with cinematic volume rendering technique (cVRT). In this very rare case, although diagnosis based on imaging differs from histologic and immunophenotypic results, the detailed visualization and demonstration help the neurosurgeons understand the complexity of the case prior to surgical planning.

Examination Protocol

Scanner

NAEOTOM Alpha

Scan area

Head

Scan mode

UHR mode (Quantum HD)Arterial / venous phase

Scan length

194.6 mm

Scan direction

Caudo-cranial

Scan time

2.4 s

Tube voltage

140 kV

Effective mAs

100 mAs

IQ level

125

Dose modulation

CARE Dose4D

CTDIvol

24.3 mGy

DLP

526 mGy*cm

Rotation time

0.25 s

Pitch

0.85

Slice collimation

120 x 0.2 mm

Slice width

0.2 / 1.0 mm

Reconstruction increment

0.2 / 0.7 mm

Reconstruction kernel

Hv60 / Qr40, QIR 4

KeV level

55 keV

Spectral reconstruction

VMI, iodine, VNC

Contrast

350 mg/mL

Volume

45 mL + 40 mL saline

Flow rate

5 mL/s

Start delay

1, Arterial phase: scan manuallytriggered when contrast agent appearedin the carotid artery at C4 level.2, Venous phase: end of the arterialphase + 8 s.

]]> (2026) Nishii | Optimization of the kernel for temporal bone imaging in PCCT https://connect.siemens-healthineers.com/zh/discussion/553/2026-nishii-optimization-of-the-kernel-for-temporal-bone-imaging-in-pcct Mon, 12 Oct 2026 10:00:12 +0000 Publication protocols Daniel Stromer 553@/zh/discussions

This study combined physical phantom testing of 11 UHR reconstruction kernels (Hr60–Hr98) with clinical visual assessment in 12 patients / 24 temporal bones. Physically, increasing kernel sharpness improved spatial resolution but increased high-frequency noise: Hr96 achieved the highest measured resolution, whereas Hr60 produced the lowest noise.

The objective system-performance analysis favored Hr72 as the best resolution–noise compromise. However, expert visual assessment of Hr60, Hr72, Hr76, and Hr84 consistently favored Hr76, particularly for visualization of the cochlea and fine middle-ear anatomy; Hr60 performed worst despite its low noise.

The practical message is that maximum sharpness is not equivalent to maximum diagnostic image quality. For UHR temporal-bone PCCT at 0.2-mm reconstruction, Hr76 appears to provide the most useful clinical balance, while Hr72 remains a reasonable slightly smoother alternative.

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Figure 5. Typical CT images used to evaluate the incudomalleolar joint. (a), (b), (c), and (d) correspond to the images reconstructed using Hr60, Hr72, Hr76, and Hr84, respectively. Sharper kernels enhanced the visualization of fine structures.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Temporal bone

Acquisition mode

Quantum HD (UHR)

Tube voltage [kV]

120

Effective mAs

Phantom: 305;

clinical cohort: 266.1 ± 18.1

IQ level

Clinical cohort: 280

Dose modulation

Automatic exposure control

CTDIvol [mGy]

Phantom: ~52;

clinical cohort: 45.63 ± 3.11

Rotation time [s]

Phantom: 0.50

Pitch

Phantom: 0.55

Detector slice collimation

120 × 0.2 mm

FOV [mm]

Phantom: 100 × 100

Matrix

512 × 512

Slice thickness

0.2 mm

Reconstruction increment

0.2 mm

Iterative reconstruction

QIR 1 (to preserve high-frequency information)

Spectral reconstruction

T3D polychromatic images

Kernels physically tested

Hr60, Hr64, Hr68, Hr72, Hr76, Hr80, Hr84, Hr89, Hr92, Hr96, Hr98

Kernels visually tested

Hr60, Hr72, Hr76, Hr84

Clinical evaluation structures

Stapes footplate, cochlea, incudomalleolar joint, overall image quality

Clinical image review

24 bilateral temporal-bone image sets; 2 radiologists

Key Results

Parameter

Main finding

Highest spatial resolution

Hr96, 10% TTF 2.712 cycles/mm

Lowest image noise

Hr60

Best physical resolution–noise balance

Hr72, highest SPF

Best visually rated kernel

Hr76 overall

Cochlea ranking

Hr76 ranked highest; significantly better than Hr84

Inter-reader agreement

ρ 0.634–0.733 for ranking and 0.834–0.939 for Likert ratings

Source:
Nishii S, Asahara T, Morimitsu Y, Kajisaki S, Akagi N, Honda M, Hayashi H, Sugaya A, Munetomo K, Higaki F, Hiraki T, Iguchi T. Optimization of the reconstruction kernel for temporal bone imaging using photon-counting detector CT: A combined physical and visual evaluation. Radiography. 2026;32(2):103274. doi:10.1016/j.radi.2025.103274.

]]> (2026) Hyska | Time-resolved PCCT estimates post-TAVI pressure gradients https://connect.siemens-healthineers.com/zh/discussion/534/2026-hyska-time-resolved-pcct-estimates-post-tavi-pressure-gradients Mon, 28 Sep 2026 08:03:04 +0000 Publication protocols Daniel Stromer 534@/zh/discussions

In 71 post-TAVI PCCT examinations from 63 patients, time-resolved cardiac PCCT enabled calculation of prosthetic-valve hemodynamics from left-ventricular volumetry and direct valve-orifice planimetry. CT-derived mean and maximum transvalvular gradients correlated strongly with echocardiography (ρ = 0.85 for both), while corrected valve area showed a correlation of ρ = 0.73.

The most clinically useful parameter was the mean transvalvular gradient (Pmean). Using echocardiographic Pmean ≥20 mmHg as the reference for potential valve dysfunction, PCCT achieved AUC 0.94, sensitivity 88.9%, specificity 88.6%, and overall accuracy 88.7%. The independently derived optimal PCCT cutoff was almost identical at 20.4 mmHg.

PCCT-derived Pmean showed much better agreement than Pmax: mean Pmean bias was only 1.6 mmHg, whereas Pmax was systematically higher and showed wider limits of agreement. This suggests that a post-TAVI PCCT already obtained for structural assessment could potentially provide opportunistic functional valve assessment, although the retrospective single-center workflow still requires external validation.

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Figure 1. Schematic overview of the CT-based workflow for post-TAVI hemodynamic assessment. Time-resolved cardiac CT was used to derive prosthetic valve hemodynamics after TAVI by combining multiphase left-ventricular volumetry, valve orifice area planimetry, quality control for excluding cases with severe mitral regurgitation and hemodynamic modeling of transvalvular flow.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Cardiac / post-TAVI prosthetic valve

Acquisition mode

Quantum HD

Scan mode

Retrospectively ECG-gated spiral

Tube voltage [kVp]

120

IQ level

60

Dose modulation

Automatic tube-current modulation; ECG-based modulation at 30–70% RR

CTDIvol [mGy]

44.1 ± 13.6

DLP [mGy·cm]

670.0 [476.0–849.5]

Effective dose [mSv]

17.4 [12.4–22.1]

Rotation time [ms]

250

Detector slice collimation

120 × 0.2 mm

Temporal reconstruction

Full cardiac cycle at 10% RR increments

Pressure-curve temporal sampling

Resampled to 66 ms

Volumetry reconstruction

Bv36; 0.8/0.6-mm thickness/increment;

512 × 512;

QIR 3

Valve-orifice reconstruction

BMI-adapted Bv60/Bv64;

0.2/0.1-mm thickness/increment;

512 × 512; QIR 4

Valve phase

Automatically selected best systolic phase

Contrast

Iodinated contrast, 350–370 mg I/mL

Contrast volume

75 mL

Injection rate

3 mL/s

Bolus triggering

Ascending aorta

Post-processing

Multiphase LV volumetry + prosthetic-valve orifice planimetry

Hemodynamic model

Flow/velocity calculation followed by simplified Bernoulli equation

Severe mitral regurgitation exclusion

CT-derived mitral regurgitation fraction >40%

Key Results

Parameter

Main finding

Study population

71 scans / 63 patients

Pmean correlation with TTE

ρ = 0.85, p < 0.001

Pmean agreement

CT 20.2 [13.4–27.6] vs TTE 20.0 [16.0–24.5] mmHg, p = 0.080;

bias 1.6 mmHg

Valve-dysfunction detection

AUC 0.94, sensitivity 88.9%, specificity 88.6%, accuracy 88.7%

Optimal PCCT Pmean cutoff

20.4 mmHg

Longitudinal follow-up

Pmean change correlated with TTE (ρ = 0.80); all 8/8 paired follow-ups concordantly classified around the 20-mmHg threshold

Source:
Hyska S, Osoria-Velasquez J, Hagar MT, et al. Photon-counting detector CT for prediction of valve dysfunction after transcatheter aortic valve implantation: Comparison with echocardiography. Journal of Cardiovascular Computed Tomography. Articles in Press. Published September 18, 2026.

]]> (2025) Mark | PCCT for Cushing Disease: Lesion localization, intraoperative findings, and outcomes https://connect.siemens-healthineers.com/zh/discussion/528/2025-mark-pcct-for-cushing-disease-lesion-localization-intraoperative-findings-and-outcomes Wed, 23 Sep 2026 08:17:26 +0000 Publication protocols Daniel Stromer 528@/zh/discussions

In 25 consecutive patients with Cushing disease undergoing transsphenoidal surgery, dynamic pituitary PCCT localized corticotroph adenomas substantially more accurately than preoperative MRI: 92% vs 56%, respectively (p = .01). PCCT identified a lesion in 24/25 patients, with only one misleading localization.

The gain was particularly relevant in MRI-negative or misleading cases. Imaging-guided targeted resection was used in 20/25 patients, and in 6 cases the surgical target relied solely on PCCT, potentially avoiding wider gland exploration or subtotal resection.

Clinical outcomes were encouraging: 84% remained in biochemical remission at a mean 5.8-month follow-up, with no new panhypopituitarism or central diabetes insipidus reported. However, this was a small, retrospective, nonblinded single-center study, so PCCT should currently be viewed as complementary to MRI rather than a replacement.

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Figure 3. llustrative case 2. Dynamic (A) and delayed (B and C) contrast-enhanced T1-weighted images at 3T demonstrate a hypoenhancing lesion in the left pituitary (blue arrows). This area is more conspicuous on color-coded iodine maps from the PCD-CT (D–F, white arrows).

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Skull base / pituitary gland

Acquisition protocol

Triggered skull base CTA followed by 4–6 delayed sellar acquisitions

Delayed acquisition interval

20 s

Tube voltage [kV]

120

IQ level

230 for CTA

Effective mAs

130–200 for delayed sellar scans

CTDIvol [mGy]

CTA: 27.2–43.5;

delayed sellar scans: 22.2–34.3

Detector configuration

120 × 0.2 mm

Reconstruction slice thickness [mm]

0.6 and 0.2

Kernel

Hr40

Iterative reconstruction

QIR 3

0.6-mm reconstruction

66-keV VMI

0.2-mm reconstruction

T3D, low-energy threshold

Iodine maps

Qr40, 0.4-mm slice thickness

Contrast

Iohexol 350

Contrast volume

100 mL

Injection rate

4 mL/s

Saline flush

35 mL for patients <136 kg

Bolus trigger

Ascending aorta, 175 HU at 90 kV

Image review

Visage PACS with color-coded display

Key Results

Parameter

Main finding

Study population

25 patients with surgically treated Cushing disease

MRI localization accuracy

56%

PCCT localization accuracy

92%, p = .01 vs MRI

PCCT lesion detection

24/25 (96%); 1 misleading localization

Targeted surgery

20/25 (80%); 6 relied solely on PCCT localization

Remission at follow-up

84% at mean 5.8 months

Source:
Mark IT, Michalopoulos G, Van Gompel J, Peris Celda M, Bancos I, Donegan D, Gruber L, Erickson D, Nagelschneider A, Yu L. Pituitary Photon-Counting Detector CT for Cushing Disease: Preoperative Lesion Localization, Intraoperative Findings, and Postoperative Outcomes. American Journal of Neuroradiology. 2025;46(12):2610–2616. doi:10.3174/ajnr.A8893.

]]> (2023) van der Bie | PCCT for TAVR planning and follow-up https://connect.siemens-healthineers.com/zh/discussion/518/2023-van-der-bie-pcct-for-tavr-planning-and-follow-up Fri, 04 Sep 2026 06:28:26 +0000 Publication protocols Daniel Stromer 518@/zh/discussions

This early case series illustrates how UHR PCCT can improve structural heart imaging before and after TAVR, particularly through sharper depiction of the aortic valve, annulus, coronary arteries, prosthetic valve frames, and vascular access routes. UHR acquisition allows 0.2-mm sections, compared with 0.4 mm in the regular PCCT mode, helping reduce calcium and metal blooming.

In pre-TAVR imaging, sharper reconstruction improved visualization of heavily calcified coronary arteries and IMAR substantially improved femoral-artery assessment despite bilateral hip prostheses. Post-TAVR, PCCT depicted hypoattenuating leaflet thickening, valve-in-valve anatomy, and an incompletely expanded left-main stent with an assessable lumen despite substantial surrounding metal and calcium.

The spectral capabilities add information beyond spatial resolution: VMI, virtual noncontrast, and iodine maps helped characterize leaflet abnormalities and distinguish iodine from calcification. These are promising proof-of-concept applications, but the report is a small case series rather than a comparative diagnostic-accuracy study.

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Figure 2: Photon-counting detector CT scan for pre–transcatheter aortic valve replacement planning in an 81-year-old female patient (with contrast material). (A) Electrocardiogram shows a highly irregular heart rate was present at the time of scanning. (B) Contrast-enhanced visualization of the aortic annulus and native aortic valve in the sagittal plane with sharp delineation of the leaflets and a small calcification in the nodule of Arantius (white arrow). (C) Ultra-high-resolution image shows the coronary arteries (Bv56 kernel, multiplanar reformatted image). (D) Conventional reconstructions at 0.6-mm section thickness (Bv40 kernel) for comparison (multiplanar reformatted image). (E, F) Axial reconstructions at the level of the femoral arteries (arrows) without (E) and with (F) iterative metal artifact reduction (IMAR) reconstruction. QIR = quantitative iterative reconstruction.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha, dual-source PCCT

Regular detector configuration

144 × 0.4 mm

UHR detector configuration

120 × 0.2 mm

UHR section thickness

0.2 mm

Pre-TAVR cardiac acquisition, Case 2

Prospectively ECG-triggered UHR CTA, 15–53% RR

Tube voltage, Case 2 [kVp]

120

IQ level, Case 2

43

CTDIvol, Case 2 cardiac [mGy]

26.8

Access-route acquisition, Case 2

High-pitch skull base to groin, 0.4-mm sections

Access-route IQ level

41

Access-route CTDIvol [mGy]

2.45

Coronary UHR kernel, Case 2

Bv56

Comparator reconstruction, Case 2

Bv40, 0.6-mm sections

Metal artifact reduction

IMAR for vascular access assessment

Post-TAVR acquisition, Case 3

120 kV; IQ 50; CTDIvol 15.2 mGy

Spectral post-processing, Case 3

VMI, virtual noncontrast, iodine map, fused iodine/VNC

Post-TAVR acquisition, Case 4

Retrospective ECG-gated UHR; 120 kV; IQ 60; CTDIvol 58 mGy

Valve-in-valve acquisition, Case 5

Full-cycle retrospective ECG-gated UHR; 120 kV; IQ 65; CTDIvol 61.5 mGy

Valve-in-valve reconstruction

Bv56; QIR 4

Ex vivo valve acquisition

UHR, 140 kV

Ex vivo reconstruction

Qr89/Qr76; QIR 4

Key Results

Parameter

Main finding

Spatial resolution

UHR PCCT enabled 0.2-mm sections vs 0.4 mm in regular PCCT mode

Pre-TAVR coronary imaging

Bv56 UHR reconstruction reduced calcium blooming compared with 0.6-mm Bv40

Access-route assessment

IMAR improved femoral-artery visualization despite bilateral hip prostheses

Leaflet assessment

PCCT demonstrated hypoattenuating leaflet thickening after TAVR and valve-in-valve TAVR

Coronary stent assessment

Left-main stent lumen remained assessable; incomplete expansion from adjacent calcification was visualized

Spectral imaging

VMI, VNC, and iodine maps provided additional characterization of valve leaflets and calcification

Source:
van der Bie J, Sharma SP, van Straten M, Bos D, Hirsch A, Dijkshoorn ML, Adrichem R, van Mieghem NMDA, Budde RPJ. Photon-counting Detector CT in Patients Pre- and Post-Transcatheter Aortic Valve Replacement. Radiology: Cardiothoracic Imaging. 2023;5(2). doi:10.1148/ryct.220318.

]]> (2024) Qin | Improvement of coronary stent visualization using UHR PCCT https://connect.siemens-healthineers.com/zh/discussion/516/2024-qin-improvement-of-coronary-stent-visualization-using-uhr-pcct Fri, 04 Sep 2026 06:20:43 +0000 Scientific publications Daniel Stromer 516@/zh/discussions

In 69 patients with 131 coronary stents, UHR PCCT with 0.2-mm slices significantly improved in-stent lumen visualization and reduced blooming artifacts compared with standard-resolution 0.6-mm reconstruction.

Among the evaluated reconstruction kernels, Bv72 provided the best overall performance, improving visualization of the stent lumen and struts while maintaining sufficient image quality for assessment.

The improved spatial resolution translated into better diagnostic performance: accuracy for detecting in-stent restenosis increased from 78.3% with standard-resolution PCCT to 88.0% with UHR-Bv72.

Clinical takeaway: UHR PCCT can mitigate blooming from metallic stent struts and may improve the reliability of non-invasive coronary stent assessment, particularly when combined with an optimized sharp reconstruction kernel.

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Source: Qin L, et al. Improvement of coronary stent visualization using ultra-high-resolution photon-counting detector CT. 2024.

]]> (2023) Vattay | VMI energy substantially alters PCCT coronary plaque quantification https://connect.siemens-healthineers.com/zh/discussion/509/2023-vattay-vmi-energy-substantially-alters-pcct-coronary-plaque-quantification Wed, 02 Sep 2026 11:20:19 +0000 Publication protocols Daniel Stromer 509@/zh/discussions

In 51 patients with 51 coronary plaques, PCCT VMI energy had a substantial effect on measured plaque attenuation and consequently on quantitative plaque composition when fixed HU thresholds were used. Mean plaque attenuation fell progressively from 723 ± 501 HU at 40 keV to 120 ± 112 HU at 180 keV, while 70-keV VMI most closely reproduced the 120-kVp T3D reference attenuation.


The effect differed by plaque component. With the primary threshold method, calcified plaque volume decreased from 138.7 ± 126.4 mm³ at 40 keV to 38.5 ± 64.6 mm³ at 180 keV, whereas low-attenuation plaque increased from 22.8 ± 24.9 to 96.0 ± 76.3 mm³. Thus, a plaque can appear quantitatively very different solely because the VMI energy changes.


Low-keV images provided the highest CNR and SNR but also more noise. The key practical implication is that fixed plaque-attenuation thresholds developed for conventional images should not simply be transferred across PCCT VMI energies; standardized energy-specific thresholds or normalization strategies are needed for reproducible plaque quantification.

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image.png

Figure1. Representative CTA images of coronary plaques reconstructed in T3D and different VMI energy levels (40, 70, 120, and 180 keV). Quantitative plaque analyses of a partially calcified-predominantly non-calcified (panel A) and partially calcified-predominantly calcified (panel B) plaque are shown in T3D and different VMI reconstructions at 40, 70, 120, and 180 keV levels. The red line illustrates the border of the vessel wall and the orange line illustrates the lumen border segmented on T3D images. Corresponding cross-sectional images are also depicted at the point of the maximal narrowing of the lesion. The same window setting was applied for all represented images: window: 800; level: 250. Abbreviations: CP, calcified plaque; HU, Hounsfield unit; LAP, low-attenuation non-calcified plaque; NCP, non-calcified plaque.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Coronary CTA

Acquisition mode

ECG-triggered PCCT

Scan mode

TurboFlash high-pitch, sequential, or helical depending on heart rate/rhythm

Tube voltage [kV]

120

IQ level

80

Dose modulation

Automatic tube current modulation

Rotation time [s]

0.25

Detector configuration

144 × 0.4 mm

Slice thickness [mm]

0.4

Reconstruction increment [mm]

0.4

Matrix

512 × 512

Kernel

Bv40

Iterative reconstruction

QIR 2

Reference reconstruction

120-kVp polychromatic T3D

VMI energies

40–180 keV in 10-keV increments

ECG phase

Diastolic 65–85% RR or systolic 200–400 ms depending on heart rate

Contrast volume

70–80 mL

Injection rate

4.5–5.0 mL/s

Contrast protocol

Four-phasic

Heart-rate control

IV beta-blocker if HR >65 bpm

Vasodilation

0.8 mg sublingual nitroglycerin if systolic BP >100 mmHg

Plaque analysis software

AutoPlaque 2.5

Primary plaque thresholds

LAP −100 to 30 HU; NCP 30–350 HU; CP >350 HU

Key Results

Parameter

Main finding

Study population

51 patients / 51 plaques

Plaque attenuation

723 ± 501 HU at 40 keV → 120 ± 112 HU at 180 keV

CNR

Highest at 40 keV: 22.1 ± 5.6; 70 keV similar to T3D

Calcified plaque volume

138.7 ± 126.4 mm³ at 40 keV → 38.5 ± 64.6 mm³ at 180 keV

Low-attenuation plaque volume

22.8 ± 24.9 mm³ at 40 keV → 96.0 ± 76.3 mm³ at 180 keV

Closest VMI to T3D

70 keV for overall attenuation/CP; 50 keV for LAP with primary thresholds

Source:
Vattay B, Szilveszter B, Boussoussou M, Vecsey-Nagy M, Lin A, Konkoly G, Kubovje A, Schwarz F, Merkely B, Maurovich-Horvat P, Williams MC, Dey D, Kolossváry M. Impact of virtual monoenergetic levels on coronary plaque volume components using photon-counting computed tomography. European Radiology. 2023;33:8528–8539. doi:10.1007/s00330-023-09876-7.

]]> (2026) Tateishi | PCCT depicts a ventricular tachycardia substrate https://connect.siemens-healthineers.com/zh/discussion/507/2026-tateishi-pcct-depicts-a-ventricular-tachycardia-substrate Tue, 01 Sep 2026 15:01:37 +0000 Case reports Daniel Stromer 507@/zh/discussions The case report hase been published by:

Tateishi, R, Nishimura, T, Tao, S. et al. Photon-Counting Detector Computed Tomography Depicts a Ventricular Tachycardia Substrate: Periaortic Septal Intramural Late Iodine Enhancement. J Am Coll Cardiol Case Rep. 2026 Apr, 31 (15) . https://doi.org/10.1016/j.jaccas.2026.107250

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image.png

Visual Summary Spatial Relationship Between LIE on PCD-CT and Arrhythmogenic Substrate(A) Preprocedural photon-counting detector computed tomography image and three-dimensional visualization using ADAS 3D software. The red arrow indicates late iodine enhancement. (B) Isochronal late activation map. Lines of conduction block with split potentials (yellow arrows) were observed in the RVOT and periaortic septal region of the LVOT, spatially corresponding to the edge of the late iodine enhancement area. Ao = aorta; LIE = late iodine enhancement; LV = left ventricle; LVOT = left ventricular outflow tract; RV = right ventricle; RVOT = right ventricular outflow tract; PA = pulmonary artery; PCD-CT = photon-counting detector computed tomography.

Background

Recent studies have demonstrated that delayed enhancement using contrast-enhanced computed tomography corresponds with late gadolinium enhancement on cardiac magnetic resonance imaging. However, few studies have evaluated scar-related ventricular tachycardia (VT) substrates using high-resolution photon-counting detector computed tomography (PCCT).

Case Summary

A 49-year-old man with cardiac sarcoidosis underwent catheter ablation of monomorphic VT. Preoperative iodine mapping on PCD-CT showed late iodine enhancement (LIE) localized to the septal region between the periaortic region and right ventricular outflow tract. Electroanatomic mapping revealed a localized abnormal voltage area and line of conduction block with split potentials colocalized with the LIE. Radiofrequency ablation was performed from both the right and left ventricular outflow tracts and successfully eliminated the VT inducibility. No ICD shocks have occurred after the procedure.

Discussion

PCD-CT provides improved signal detection and superior spatial resolution, enabling visualization of VT substrates in anatomically challenging regions. In patients who are contraindicated for cardiac magnetic resonance imaging, PCD-CT serves as a valuable alternative imaging modality.

Take-Home Messages

The higher spatial resolution of PCD-CT enables a more precise detection of periaortic substrates, whereas detecting late gadolinium enhancement on cardiac magnetic resonance imaging is challenging given a thin myocardium and anatomical complexity.•Because PCD-CT does not have the same restrictions as cardiac magnetic resonance imaging, it can be used in patients with non–MRI-conditional implantable cardioverter-defibrillators to accurately identify and locate ventricular tachycardia substrates.

]]> (2024) Hagar | UHR PCCT accurately evaluates coronary stent patency https://connect.siemens-healthineers.com/zh/discussion/504/2024-hagar-uhr-pcct-accurately-evaluates-coronary-stent-patency Fri, 28 Aug 2026 11:00:01 +0000 Publication protocols Daniel Stromer 504@/zh/discussions

In 18 patients with 44 coronary stents, ultra-high-resolution (UHR) PCCT angiography achieved high diagnostic accuracy for detecting ≥50% in-stent stenosis compared with invasive coronary angiography (ICA). Both readers identified all 5 stenotic stents, yielding 100% sensitivity.

Specificity and overall accuracy were 92.3% and 93.2% for reader 1 and 87.2% and 88.6% for reader 2. Most importantly, the negative predictive value was 100% for both readers, supporting UHR PCCT as a strong noninvasive technique for ruling out clinically relevant in-stent restenosis.

Stent-lumen image quality was generally good to excellent, with only 3/44 stents considered nondiagnostic by both readers. Despite residual stent blooming of approximately 38–40%, the 0.2-mm reconstruction with a sharp Bv60 kernel provided sufficient lumen visualization for reliable clinical assessment in more than 90% of stents.

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Figure 4. Ultra-high-resolution photon-counting detector CT angiography (PCD-CTA) of the heart of a 69-year-old male patient with severe aortic valve stenosis and a history of coronary stent implantation in the distal left main and proximal left anterior descending artery (LAD) (arrowhead in A, B, and C). A Three-dimensional cinematic rendering of the heart, showing the stent in the LAD. B Curved multiplanar reformation showing the absence of in-stent stenosis. The stent was rated as “excellent”—Likert 1 by one reader—and as “good”—Likert 2 by the other reader. C Invasive coronary angiography at caudal 30° view, verifying stent patency

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Software

syngo CT VA50; syngo.via VB60

Scan area

Coronary arteries as part of TAVI-CT

Scan mode

Ultra-high resolution

Acquisition mode

ECG-synchronized UHR PCCT angiography

Detector slice collimation

120 × 0.2 mm

Matrix

1024 × 1024

Field of view [mm]

180 × 180

Slice thickness [mm]

0.2

Reconstruction increment [mm]

0.1

Reconstruction kernel

Bv60

Iterative reconstruction

QIR 3

ECG reconstruction

Automatically selected best-systolic and best-diastolic phases plus multiphase data

Contrast agent

Iopromide, Ultravist 370

Contrast protocol

70 mL contrast followed by 40 mL isotonic saline + 30 mL contrast mixture

Injection rate

5.0 mL/s

Bolus triggering

Aortic root, 130-HU threshold

Trigger delay

10 s

Patient preparation

No nitroglycerin or beta-blockers administered

Key Results

Parameter

Main finding

Study population

18 patients / 44 coronary stents

In-stent stenosis prevalence

5/44 (11.4%)

Sensitivity

100% for both readers

Specificity

92.3% reader 1; 87.2% reader 2

Diagnostic accuracy

93.2% reader 1; 88.6% reader 2

Negative predictive value

100% for both readers

Inter-reader agreement

90.1%; κ = 0.72

Stent blooming

37.9 ± 9.6% and 40.1 ± 8.9%

Source:
Hagar MT, Soschynski M, Saffar R, Molina-Fuentes MF, Weiss J, Rau A, Schuppert C, Ruile P, Faby S, Schibilsky D, von zur Muehlen C, Schlett CL, Bamberg F, Krauss T. Ultra-high-resolution photon-counting detector CT in evaluating coronary stent patency: a comparison to invasive coronary angiography. European Radiology. 2024;34:4273–4283. doi:10.1007/s00330-023-10516-3.

]]> (2025) Zhang | UHR PCCT versus 40-keV VMI for abdominal artery visualization https://connect.siemens-healthineers.com/zh/discussion/497/2025-zhang-uhr-pcct-versus-40-kev-vmi-for-abdominal-artery-visualization Fri, 28 Aug 2026 10:20:38 +0000 Publication protocols Daniel Stromer 497@/zh/discussions

This prospective study compared 0.2-mm ultra-high-resolution (UHR) PCCT with 1-mm standard-resolution 40-keV VMI for abdominal CTA in 94 participants, equally divided between full-dose and low-dose protocols. Standard-resolution 40-keV VMI provided significantly higher SNR and CNR than all UHR reconstructions.


UHR reconstruction nevertheless improved vessel sharpness, particularly with the sharper Bv56 and Bv60 kernels, but the associated increase in image noise reduced overall image quality. The smoother Bv48 UHR reconstruction provided the best balance, with overall quality comparable to standard-resolution 40-keV VMI.


Importantly, abdominal artery visibility was broadly comparable across full- and low-dose reconstructions. The authors therefore favor 1-mm low-dose 40-keV VMI for routine abdominal CTA, while 0.2-mm UHR Bv48 may be valuable when very thin slices and visualization of distal vascular segments are specifically required.

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Figure 5. Representative example of two participants who both underwent full-dose scan. A A 71-year man with a BMI of 19.7 kg/m2 underwent abdominal CTA using a FD protocol with CTDIvol, DLP, SSDE, and effective dose of 6.23 mGy, 212.0 mGy·cm, 9.06 mGy, and 3.18 mSv, respectively. The data were reconstructed into FD_UHR_Bv48, FD_UHR_Bv56, FD_UHR_Bv60, FD_SR_Bv40 images, respectively. The UHR images have higher image noise, but better vessel sharpness. The overall quality of FD_UHR_Bv48, and FD_SR_Bv40 images are comparable. The FD_UHR_Bv56 and FD_UHR_Bv60 images presented better vessel sharpness than but were damaged by higher image noise. B–D Another 57-year woman with a BMI of 20.8 kg/m.2 underwent abdominal CTA using a FD protocol with CTDIvol, DLP, SSDE, and effective dose of 4.06 mGy, 111.0 mGy·cm, 6.25 mGy, and 1.67 mSv, respectively. The data were reconstructed into FD_UHR_Bv48, and FD_SR_Bv40 images, respectively. B The left gastric artery is only visible in axial FD_UHR_Bv48 images (solid arrow), and the soft tissue between the abdominal aorta and celiac trunk were better depicted (open arrow). C There were more visible vascular segments of left renal artery in coronal FD_UHR_Bv48 images than FD_SR_Bv40 images (solid arrow). D The left renal artery can be better visualized to the more distal vascular segments in volume-rendered FD_UHR_Bv48 images than FD_SR_Bv40 images (solid arrow). The volume-rendered FD_UHR_Bv48 images allowed more visible vascular segments of superior mesenteric artery (open arrow).

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Software

Syngo.CT VA50-SP1; syngo.via VB60

Scan area

Abdominal CTA

Scan mode

UHR

Acquisition mode

PCCT

Tube voltage [kV]

120

Effective mAs [mAs]

CARE Dose4D automatic

IQ level

145 full dose; 90 low dose

Dose modulation

CARE Dose4D

CTDIvol [mGy]

Protocol-dependent; significantly lower with low-dose protocol

DLP [mGy·cm]

Protocol-dependent; significantly lower with low-dose protocol

Temporal resolution [ms]

n.a.

Rotation time [s]

0.50

Pitch

0.8

Matrix

Automatically adjusted

Field of view [mm]

Automatically adjusted

Detector slice collimation

120 × 0.2 mm

Acquisition slice thickness

0.2 mm

Slice width [mm]

UHR: 0.2; SR: 1.0

Reconstruction increment [mm]

UHR: 0.2; SR: 0.7

Reconstruction kernel

UHR: Bv48, Bv56, Bv60; SR: Bv40

Iterative reconstruction

UHR: QIR 4; SR: QIR 3

Reconstruction

UHR polychromatic vs standard-resolution 40-keV VMI

Reconstruction comparison

FD_UHR_Bv48, FD_UHR_Bv56, FD_UHR_Bv60, FD_SR_Bv40, LD_UHR_Bv48, LD_SR_Bv40

Contrast agent

Ultravist 370

Contrast volume

1.5 mL/kg

Saline flush

n.a.

Injection rate

3.0 mL/s

Bolus triggering

Abdominal aorta

Arterial phase

12-s delay after aortic enhancement

Additional reconstructions

Axial, coronal, volume-rendered images

Key Results

Parameter

Main finding

Study population

94 participants; 47 full dose + 47 low dose

SNR / CNR

Significantly higher with 1-mm 40-keV VMI than UHR, P < 0.001

Vessel sharpness

Highest with UHR Bv56/Bv60, but with substantially more noise

Best UHR balance

0.2-mm Bv48 provided comparable overall quality to 40-keV VMI

Artery visibility

No significant overall difference among the six reconstruction series

Preferred strategy

Low-dose 1-mm 40-keV VMI for routine CTA; 0.2-mm UHR Bv48 when thinner slices are required

Source:
Zhang H, Xing Y, Wang L, Hu Y, Xu Z, Chen H, Lu J, Yang J, Ding B, Hu W, Zhong J. Ultra-High-Resolution Photon-Counting Detector CT Benefits Visualization of Abdominal Arteries: A Comparison to Standard-Reconstruction. Journal of Imaging Informatics in Medicine. 2025;38:1891–1903. doi:10.1007/s10278-024-01232-5.

]]> (2024) Wang | Low-dose ultra-high-resolution PCCT for visceral artery CTA https://connect.siemens-healthineers.com/zh/discussion/496/2024-wang-low-dose-ultra-high-resolution-pcct-for-visceral-artery-cta Fri, 28 Aug 2026 10:12:50 +0000 Scientific publications Daniel Stromer 496@/zh/discussions

Prospective study testing whether low-dose (LD) ultra-high-resolution (UHR) photon-counting CT can preserve diagnostic image quality for visceral artery CTA. The study included 57 patients in the full-dose group and 57 in the low-dose group.


Each acquisition was reconstructed two ways: 0.2 mm / Bv48 / QIR 4 and 1 mm / Bv40 / QIR 3. Objective SNR/CNR and subjective noise, vessel sharpness, overall quality, and visibility of nine visceral arteries were assessed.


The 0.2-mm UHR reconstruction had lower SNR and CNR than the 1-mm reconstruction, but nevertheless achieved better qualitative image quality, particularly for depiction of tiny arteries on volume-rendered images (p < 0.001).


Importantly, full-dose imaging generally did not provide significantly higher SNR/CNR than low-dose imaging at the same slice thickness. Exceptions were SNR for the common hepatic, splenic, and bilateral renal arteries with the 0.2-mm reconstruction.


Low-dose scanning also did not significantly impair image quality in overweight patients within the same reconstruction setting.


Visibility of the nine evaluated visceral arteries was largely comparable between full- and low-dose protocols, with limited exceptions involving the superior mesenteric and left gastric arteries.

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Practical PCCT takeaway

The study supports using low-dose UHR PCCT for visceral CTA while retaining very thin 0.2-mm reconstructions. Rather than sacrificing spatial resolution to improve conventional SNR/CNR metrics, UHR PCCT can exploit thin slices to improve depiction of small arterial anatomy. The authors conclude that low-dose UHR was adequate for clinical visceral-artery evaluation and that 0.2-mm reconstruction particularly improves small-vessel depiction.

Protocol

NAEOTOM Alpha PCCT; UHR acquisition; 57 FD + 57 LD patients; 0.2-mm/Bv48/QIR4 versus 1-mm/Bv40/QIR3 reconstructions.

Source: Wang L, Hu Y, Zhong J, et al. Low-dose Ultra-high-resolution Photon-Counting Detector CT for Visceral Artery CT Angiography: A Preliminary Study. Academic Radiology. 2024;31(12):5087–5099. doi:10.1016/j.acra.2024.06.044. Published online August 6, 2024.

]]> (2026) Habib Geryes | Pediatric PCCT protocols and radiation exposure https://connect.siemens-healthineers.com/zh/discussion/490/2026-habib-geryes-pediatric-pcct-protocols-and-radiation-exposure Fri, 28 Aug 2026 06:54:37 +0000 Publication protocols Daniel Stromer 490@/zh/discussions

This multicenter retrospective study evaluated 6,464 PCCT examinations in 4,772 pediatric patients across three French institutions and provides practical acquisition/reconstruction protocols across ten body regions.


The cohort had a mean age of 7.9 ± 5.5 years (4 days–17.9 years); nearly one-third of examinations involved children <15 kg and <4 years. Chest and head examinations were the most frequent.


Protocols were explicitly designed to balance radiation-dose reduction, diagnostic image quality, motion reduction, and workflow efficiency, with dose analysis stratified into five weight groups.


The authors conclude that the results support safe clinical integration of pediatric PCCT, while emphasizing that the proposed protocols are a flexible framework for local optimization rather than fixed universal settings.

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Protocols

We created an cheat sheet from the protocol table via AI:

image.png

Key Results

Parameter

Result

Patients

4,772

PCCT examinations

6,464

Mean age

7.9 ± 5.5 years

Age range

4 days–17.9 years

Mean weight

29.6 ± 20.3 kg

Weight range

2–79 kg

Children <15 kg / <4 years

2,110 examinations (32.64%)

Most frequent examination

Chest: 2,168 (33.54%)

Second most frequent

Head: 1,675 (25.91%)

Noncontrast head CTDIvol

16.1–24.0 mGy across weight groups

Noncontrast head DLP

311–608 mGy·cm

Noncontrast chest CTDIvol

0.3–0.8 mGy

Noncontrast chest DLP

7–27 mGy·cm

Temporal bone CTDIvol

22.7–33.8 mGy

Dose relationship

CTDIvol and DLP increased with patient weight

The patient distribution and examination frequencies are reported in the study results. Dose levels varied substantially by examination and patient weight; temporal-bone examinations had particularly high CTDIvol because of UHR/high-kV acquisition, whereas noncontrast chest imaging operated at very low dose levels.

For example, pooled across weight groups, noncontrast chest PCCT had a median CTDIvol of 0.4 mGy and DLP of 11.9 mGy·cm, while the dedicated low-dose chest protocol reached approximately 0.1 mGy and 4.0 mGy·cm, respectively.

Practical take-home

This is primarily a protocol and dose-reference paper, rather than an image-quality superiority study. Its major value is the large real-world pediatric dataset and the detailed, indication-specific protocol framework. PCCT allows aggressive pediatric dose optimization through weight-/task-adapted CARE keV, Sn filtration, fast-pitch acquisition, UHR where spatial resolution is necessary, and spectral reconstructions from contrast-enhanced QuantumPlus scans.

Source: Habib Geryes B, Moalla S, De Saint Etienne E, et al. Photon-counting CT in pediatric patients: A multi-institutional evaluation of protocols and radiation exposure in 4,772 patients. Diagnostic and Interventional Imaging. 2026;107(5):186–197. doi:10.1016/j.diii.2025.11.010.

]]> (2026) Huang | UHR PCCT with low-keV improves preoperative pancreatic cancer assessment https://connect.siemens-healthineers.com/zh/discussion/489/2026-huang-uhr-pcct-with-low-kev-improves-preoperative-pancreatic-cancer-assessment Fri, 28 Aug 2026 06:11:40 +0000 Scientific publications Daniel Stromer 489@/zh/discussions

Combining UHR PCCT with low-keV virtual monoenergetic imaging (VMI) improved visualization of pancreatic ductal adenocarcinoma (PDAC), peripancreatic vessels, and fine pancreatic anatomy; the study identified 0.4-mm slices at 45 keV as the best overall reconstruction strategy for preoperative assessment.


40-keV VMI produced the highest quantitative CNR and SNR for tumors and peripancreatic vessels, while 45–50 keV at 0.4-mm slice thickness achieved better qualitative visualization of fine anatomical structures, balancing spectral contrast enhancement with the high spatial resolution of PCCT.


The combination of high spatial resolution and spectral information from PCCT may improve tumor–vessel delineation and visualization of fine structures relevant to PDAC staging and surgical planning, demonstrating the complementary value of UHR acquisition and spectral reconstruction in abdominal oncology imaging.

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Source: Huang R, Yang Y, Gao M, et al. Eur J Radiol. 2026;195:112596.

]]> (2026) Tóth | Spectral black-blood PCCT for high-resolution carotid vessel wall imaging https://connect.siemens-healthineers.com/zh/discussion/488/2026-toth-spectral-black-blood-pcct-for-high-resolution-carotid-vessel-wall-imaging Fri, 28 Aug 2026 05:37:26 +0000 Scientific publications Daniel Stromer 488@/zh/discussions

A novel spectral black-blood CT (BBCT) reconstruction used the spectral information from PCCT to suppress intraluminal iodine from a routine single-phase CTA dataset, enabling high-resolution carotid vessel wall imaging without an additional scan, contrast administration, or dedicated acquisition.

Compared with conventional CTA, spectral BBCT significantly improved wall–lumen delineation and carotid plaque conspicuity while preserving overall image quality. An iodine ratio of 2.0 provided the best balance between lumen suppression and vessel wall visualization.

BBCT improved reader agreement for high-risk plaque features including intraplaque hemorrhage, lipid-rich necrotic core, and thin fibrous cap. However, possible subtraction-related sensitivity loss means BBCT should currently be viewed as a complementary PCCT reconstruction alongside conventional CTA, rather than a standalone replacement.

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Source: Tóth A, Hagar MT, Halfmann MC, et al. Investigative Radiology. Published ahead of print August 18, 2026. doi:10.1097/RLI.0000000000001309.

]]> (2025) Shami | Clinical PCCT to detect intra-plaque haemorrhage and thrombus in carotid plaques https://connect.siemens-healthineers.com/zh/discussion/483/2025-shami-clinical-pcct-to-detect-intra-plaque-haemorrhage-and-thrombus-in-carotid-plaques Thu, 27 Aug 2026 09:04:50 +0000 Publication protocols Daniel Stromer 483@/zh/discussions

This proof-of-concept study is described as the first clinical PCCT study to characterize high-risk human carotid plaque features in living patients, using histology from subsequent carotid endarterectomy as the reference. The cohort comprised 10 symptomatic patients.


Spectral PCCT could differentiate multiple plaque components. Calcification was distinguishable from all other features across 40–190 keV, while intraplaque haemorrhage (IPH) was also distinguishable from the other tissue classes except thrombus. Thrombus was distinguishable from other features (except IPH) over 40–166 keV.


The key clinical implication is that PCCT may move carotid CTA beyond assessment of stenosis and calcification toward non-invasive characterization of rupture-prone plaque components, particularly IPH and thrombus, potentially improving cardiovascular risk stratification.

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Figure 1. Comparison of attenuation of distinct atherosclerotic plaque features scanned by PCCT in living patients and corresponding microscopic images after carotid endarterectomy. High-resolution PCCT angiography demonstrates carotid stenosis, with matched ROIs on 70-keV PCCT images and histology. Spectral HU measurements from 40–190 keV characterize calcium, IPH, thrombus, lipid core, fibrosis, and necrosis and demonstrate feature-specific spectral behavior.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha

Scan area

Carotid arteries

Reference standard

Histology after carotid endarterectomy

Timing

PCCT mean 1.7 ± 1.6 days before surgery

Acquisition mode

Quantum Plus

Single-source

Tube voltage [kVp]

120

Image quality level

150

Exposure control

CARE Dose4D

Collimation

120 × 0.2 mm

Rotation time

0.5 s

Pitch

0.85

Contrast reconstruction

Qr40 and Bv64, QIR 4

Non-contrast reconstruction

Qr40 and Br84, QIR 3

Slice thickness

0.4 mm

Increment

0.2 mm

Spectral analysis

40–190 keV in 1-keV increments

Representative VMI

70 keV

Contrast

Omnipaque, 350 mg I/mL

Plaque characterization

Feature

Histological reference / n

PCCT finding

Calcification

von Kossa / 340

Distinguished from all other features across 40–190 keV

IPH

Glycophorin A / 106

Distinguished from all features except thrombus

Thrombus

Glycophorin A / 43

Distinguished from other features except IPH at 40–166 keV

Lipid core

oxLDL / 107

Differentiated from fibrosis across all energies

Fibrosis

Russell-Movat / 470

Differentiated from lipid core throughout spectral range and necrosis at lower energies

Necrosis

Histological tissue/cell absence / 62

Spectral differentiation more limited

The study used 1,128 manually matched histology-PCCT ROIs, with alignment validated by an experienced imaging cardiologist; blinded inter-observer assessment showed 82% overall agreement.

Key takeaway

PCCT provided in-vivo spectral tissue characterization of carotid plaques, including detection of intraplaque haemorrhage and thrombus, rather than merely quantifying stenosis or calcium. However, this remains an early proof-of-concept: only 10 patients were included, all were of the same sex and ethnicity, and there was no direct accuracy comparison with conventional CT or MRI.

Source: Shami A, Sun J, Celander M, et al. Clinical photon-counting computed tomography in living patients detects intra-plaque haemorrhage and thrombus in carotid plaques. European Heart Journal. 2025;46(46):5045–5048. Published August 29, 2025. doi:10.1093/eurheartj/ehaf707.

]]> (2026) Schwartz | Streamlined PCCT myelography protocol for detection of CSF-venous fistulas https://connect.siemens-healthineers.com/zh/discussion/476/2026-schwartz-streamlined-pcct-myelography-protocol-for-detection-of-csf-venous-fistulas Wed, 26 Aug 2026 08:03:46 +0000 Scientific publications Daniel Stromer 476@/zh/discussions

A streamlined PCCT myelography protocol enabled whole-spine evaluation at 0.2 × 0.1 mm resolution while limiting scanner time to approximately 15 minutes, making high-resolution CSF leak imaging feasible in a busy clinical setting.

In 35 patients with previously inconclusive spine imaging, PCCT definitively identified a CSF leak in 34% (12/35) and suggested a potential leak site in another 23% (8/35). Resistive inspiration was most frequently judged the best breathing phase for leak detection.

PCCT findings enabled more targeted management after extensive prior workup; among treated patients, 62% (18/29) achieved symptom relief following surgery, embolization, or blood/fibrin glue patching.

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Exam protocol

  • Intrathecal contrast was administered under fluoroscopic guidance, followed by transport to the PCCT scanner with the patient maintained in a decubitus position.
  • The entire spine was imaged with UHR PCCT at 0.2 × 0.1 mm spatial resolution using three breathing phases: resistive inspiration, end inspiration, and Valsalva, resulting in six series per examination.
  • In all but two patients, imaging was performed on two consecutive days, once in each decubitus position, allowing side-dependent assessment for CSF-venous fistulas while keeping each scanner session to about 15 minutes.

Source: Schwartz FR, Huang RY, DeSalvo MN, et al. AJNR Am J Neuroradiol. 2026;47(6):1737–1742.

image.png ]]> (2024) Halfmann | UHR PCCTA improves coronary stenosis assessment and CAD-RADS classification https://connect.siemens-healthineers.com/zh/discussion/462/2024-halfmann-uhr-pccta-improves-coronary-stenosis-assessment-and-cad-rads-classification Fri, 07 Aug 2026 05:23:51 +0000 Scientific publications Daniel Stromer 462@/zh/discussions Access publication

Key takeaways

UHR PCCTA significantly improved the assessment of calcified coronary stenoses by reducing calcium blooming artifacts, resulting in more accurate stenosis quantification than standard-resolution CCTA.

Compared with standard-resolution imaging, UHR PCCTA reclassified 54.4% of patients to a lower CAD-RADS category, with fewer recommendations for downstream functional testing and invasive coronary angiography.

The findings support PCCT as an important advance for evaluating patients with suspected or known coronary artery disease, particularly in the presence of coronary calcification where conventional CCTA has limited specificity.

Source: Halfmann et al. Radiology. 2024;310(2).

]]> (2026) Szilveszter | UHR PCCT improves detection of low-attenuation coronary plaque https://connect.siemens-healthineers.com/zh/discussion/460/2026-szilveszter-uhr-pcct-improves-detection-of-low-attenuation-coronary-plaque Tue, 04 Aug 2026 08:16:02 +0000 Publication protocols Daniel Stromer 460@/zh/discussions

This phantom study demonstrates that ultra-high-resolution (UHR) photon-counting CT (PCCT) substantially improves visualization of low-attenuation plaque (LAP) compared with standard-resolution PCCT and a clinically used energy-integrating detector CT (EID-CT) protocol.


The combination of UHR acquisition (120 × 0.2 mm collimation), sharp Qr72 reconstruction kernels, and QIR 2–4 provided the highest spatial resolution and the most accurate attenuation values, allowing visualization of 1-mm LAP components that conventional EID-CT failed to resolve.


Higher virtual monoenergetic reconstructions (130 keV) reduced iodine blooming and improved differentiation between calcium, iodine, and lipid-rich plaque components, suggesting optimized PCCT protocols may improve future coronary plaque characterization.

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image.png

Figure 2. Low-attenuation plaque visualization on standard, UHR, and reference images using PCD-CT. Compared with the standard resolution (Qr40) and ultra-high resolution (Qr72) reconstructions, the Temporal Bone (Hr84) protocol provided markedly superior delineation of fine plaque morphology in the smallest plaque inlay (LAP4mm) using PCD-CT. This phantom design simulates a true-to-scale 4 mm coronary plaque, underscoring the relevance of these findings to real coronary artery dimensions.

Source:
@Bálint Szilveszter, Kolossváry M, Kubovje A, et al. Mixed coronary plaque phantom analysis by photon-counting CT: impact of calcium and iodine on low-attenuation plaque detection. European Heart Journal – Imaging Methods and Practice. 2026;4(3):qyag119.

image.png

Protocol (PCCT)

Parameter

Standard mode

UHR mode

High-resolution reference standard

Cardiac, sequential, half-rotation

Cardiac, sequential, half-rotation

Temporal Bone, helical, full-rotation

Tube voltage (kVp)

120

120

140

Kernel

Qr40 & Qr72

Qr40 & Qr72

Hr 84

Field of view (mm)

102

102

100

Single collimation width (mm)

0.4

0.2

0.2

Rotation time (s)

0.25

0.25

0.5

Matrix size

512 × 512

512 × 512

768 × 768

Pixel dimensions (mm × mm)

0.20 × 0.20

0.20 × 0.20

0.13 × 0.13

Computed tomography dose index volume (mGy)

13.98

14.79

55.05

Energy levels (keV)

40,70,100,130, T3D

T3D

T3D

Focal spot (mm)

0.8/1.2

0.8/1.2

0.6/0.7

]]> (2026) Pannenbecker | UHR PCCT pulmonary angiography improves pulmonary artery visibility/confidence https://connect.siemens-healthineers.com/zh/discussion/433/2026-pannenbecker-uhr-pcct-pulmonary-angiography-improves-pulmonary-artery-visibility-confidence Fri, 26 Jun 2026 13:31:25 +0000 Publication protocols Daniel Stromer 433@/zh/discussions

Ultra-high-resolution (UHR) photon-counting CT pulmonary angiography significantly improved visualization of peripheral pulmonary arteries and increased radiologists' diagnostic confidence compared with state-of-the-art dual-energy EID-CT.

UHR-PCD-CT achieved substantially higher pulmonary arterial enhancement (568–623 HU vs. 397 HU) while maintaining similar SNR and CNR, enabling superior subjective image quality and iodine map quality.

A low-dose UHR protocol (IQ25) reduced radiation dose by approximately 36% compared with EID-CT while maintaining the same image quality and diagnostic confidence as the higher-dose UHR protocol (IQ50).

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image.png image.png

Figure 4. Increased peripheral pulmonary artery visibility with ultra-high-resolution photon-counting CT. UHR-PCD-CTPA at IQ50 (A) and IQ25 (B) vs. EID-CTPA (C). Representative measurements of the minimal distance of the last discernible pulmonary artery branch to the pleura are shown (orange line, in mm). CTPA, CT pulmonary angiography; EID, energy-integrating detector; IQ, image quality index; PCD, photon-counting detector; UHR, ultra-high resolution

Source: Pannenbecker P, Rüth C, Grunz JP, et al. Increasing pulmonary artery visibility and diagnostic confidence with ultra-high resolution photon-counting detector CT pulmonary angiography. European Radiology. 2026.

Protocol

Detail

Value

Scanner

NAEOTOM Alpha.Peak

Software

VB10 PCCT

VB80D sybgo.via

Scan area

CT Pulmonary Angiography (CTPA)

Scan mode

Quantum HD

Acquisition mode

Photon-counting CT

Scan direction

Craniocaudal

Tube voltage [kV]

140

Effective mAs [mAs]

IQ25 or IQ50 (vendor-specific IQ level)

IQ level

25 or 50

Dose modulation

IQ-based automatic exposure control

CTDIvol [mGy]

IQ25: 3.0 ± 1.0; IQ50: 6.7 ± 2.4

DLP [mGy·cm]

Not reported

Pitch

3.2 (Flash mode)

Matrix

n.r.

Slice collimation [mm]

120 × 0.2

Slice width [mm]

0.4

Reconstruction kernel

Bv48

Reconstruction

55 keV virtual monoenergetic images (VMI)

Iodine maps

Yes

Contrast agent

Imeron 350

Contrast volume

40 mL

Flow rate

4 mL/s

Bolus triggering

100 HU in pulmonary trunk; 5 s delay

Patient preparation

Standard pulmonary embolism protocol

Comparison protocol (reference EID-CT)

Detail

Value

Scanner

SOMATOM Force

Acquisition

Dual-energy EID-CT

Tube voltage

90/Sn150 kV

Pitch

0.55

Slice collimation

2 × 96 × 0.6 mm

Slice width

0.6 mm

Reconstruction kernel

Bv36

Contrast volume

50 mL

CTDIvol

4.7 ± 2.7 mGy

]]> (2026) Huflage | Comparison of IMAR presets for UHR angiography for total kneeendoprosthesis https://connect.siemens-healthineers.com/zh/discussion/443/2026-huflage-comparison-of-imar-presets-for-uhr-angiography-for-total-kneeendoprosthesis Wed, 15 Jul 2026 12:03:28 +0000 Publication protocols Daniel Stromer 443@/zh/discussions
  • Among all seven available iterative metal artifact reduction (IMAR) presets, the IMARDental preset unexpectedly provided the strongest reduction of metal artifacts around total knee endoprostheses during ultra-high-resolution photon-counting CT angiography.
  • IMARDental significantly improved objective artifact reduction and achieved the highest subjective diagnostic confidence for assessing the popliteal artery, while maintaining image noise comparable to all other reconstruction presets.
  • The study demonstrates that IMAR preset selection should be task-based rather than anatomy-based, suggesting that the default "Extremity" preset is not necessarily optimal for vascular assessment adjacent to metallic implants.

    • Access publication

    image.png

    Figure 2. The seven available iterative metal artifact reduction (IMAR) presets have vastly different influence on the diagnostic assessability of the popliteal artery (red arrows) in ultra-high-resolution photon-counting CT angiography of the lower extremity.

    Source:
    Huflage H, Kunz AS, Wech T, et al. Comparison of Iterative Metal Artifact Reduction Presets In Ultra-high-resolution Photon-counting CT Angiography of Patients with Total Knee Endoprosthesis. Academic Radiology. 2026.

    Protocol

    Detail

    Value

    Scanner

    NAEOTOM Alpha

    Software

    VB10

    Scan area

    Lower extremity CTA

    Scan mode

    Quantum Plus

    Scan direction

    Craniocaudal

    Tube voltage [kV]

    140

    Effective mAs [mAs]

    CARE keV

    IQ level

    64

    Dose modulation

    Active

    CTDIvol [mGy]

    n.a.

    DLP [mGy·cm]

    Median 892 (747–1010.5)

    Rotation time [s]

    1.0

    Pitch

    1.0

    Field of view [mm]

    200

    Slice collimation [mm]

    120 × 0.2

    Slice width [mm]

    0.8

    Reconstruction increment [mm]

    0.8

    Reconstruction kernel

    Bv56

    Iterative reconstruction

    QIR 4

    Virtual monoenergetic images

    55 keV

    Metal artifact reduction

    IMAR off + Extremity, Hip, Pacemaker, Lung coils, Shoulder, Dental, Neuro coils presets

    Contrast agent

    Imeron 400 mg I/mL

    Contrast volume

    90 mL

    Saline chaser

    30 mL

    Flow rate

    3.0 mL/s

    Bolus triggering

    ROI in infrarenal aorta, 100 HU threshold, 18 s delay

    ]]>     (2022) Mergen | UHR coronary CT angiography with PCCT: feasibility and optimal reconstruction https://connect.siemens-healthineers.com/zh/discussion/438/2022-mergen-uhr-coronary-ct-angiography-with-pcct-feasibility-and-optimal-reconstruction Sat, 27 Jun 2026 05:30:15 +0000 Publication protocols Daniel Stromer 438@/zh/discussions

    Ultra-high-resolution (UHR) coronary CTA with photon-counting CT was feasible in patients with a high coronary calcium burden, providing improved visualization of calcified plaques and adjacent coronary lumen compared with conventional 0.6 mm reconstructions.


    Reconstruction kernel selection proved critical. Moderate sharp kernels (particularly Bv64) achieved the best balance between blooming reduction, vessel sharpness, and image noise, while very sharp kernels increased noise without further improving blooming.


    The study established an optimized UHR coronary PCCT protocol (0.2 mm slices, Bv64 kernel, 200 mm FOV, 512×512 matrix), laying the technical foundation for later clinical UHR coronary PCCT studies.

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    image.png

    Figure 5. Axial images from ultra-high-resolution CCTA (slice thickness, 0.2 mm) with PCD-CT of the left main and the proximal left anterior descending artery. Although borders of calcified plaques have a blurry appearance on reconstructions with low kernel strengths, reconstructions with moderate kernel strengths (eg, Bv64) enable an excellent delineation of calcified plaques and adjacent vessel lumen before increased image noise on reconstructions with high kernel strengths (eg, Bv89) hampers vessel lumen visualization.

    Protocol

    Detail

    Value

    Scanner

    NAEOTOM Alpha

    Software

    syngo CT VA50

    Scan area

    Coronary CTA

    Scan mode

    Retrospective ECG-gated dual-source spiral UHR mode

    Acquisition mode

    Quantum HD

    Scan direction

    Helical

    Tube voltage [kV]

    120

    Effective mAs [mAs]

    IQ level 64 (automatic tube current modulation)

    IQ level

    64

    Dose modulation

    Automatic tube current modulation

    CTDIvol [mGy]

    38.2 ± 11.1

    DLP [mGy·cm]

    n.a.

    Temporal resolution [ms]

    66

    Rotation time [s]

    0.25

    Pitch

    0.19–0.32 (heart rate dependent)

    Matrix

    512 × 512 or 1024 × 1024

    Field of view [mm]

    200 × 200 (Bv40–72), 150 × 150 (Bv89)

    Slice collimation [mm]

    120 × 0.2

    Slice width [mm]

    0.2 (reference reconstruction additionally 0.6 mm)

    Reconstruction increment [mm]

    0.2 (0.3 mm for reference reconstruction)

    Reconstruction kernel

    Bv40, Bv44, Bv56, Bv60, Bv64, Bv72, Bv80, Bv89

    Iterative reconstruction

    QIR level 4

    Reconstruction comparison

    Eight UHR vascular kernels (0.2 mm) versus reference Bv40 at 0.6 mm

    ECG gating

    Retrospective

    ECG pulsing

    Fixed 30–80% R-R interval

    Contrast agent

    Ultravist 370 (iopromide 370 mg iodine/mL)

    Contrast volume

    50–80 mL (body weight dependent)

    Flow rate

    3.3–4.4 mL/s

    Saline chaser

    20 mL

    Bolus triggering

    140 HU in ascending aorta at 90 kV

    Patient preparation

    Sublingual nitroglycerin (2.5 mg isosorbide dinitrate); no beta-blockers

    Phase selection

    Least-motion cardiac phase reconstructed individually

    Key Results

    Parameter

    Main finding

    Feasibility

    UHR coronary PCCT successful in all 20 patients

    Median calcium score

    479

    Best reconstruction kernel

    Bv64

    Lowest blooming

    Bv72 (39.7%)

    Highest vessel sharpness

    Bv89 (2383 ΔHU/mm)

    Best plaque/lumen delineation

    Bv64–Bv72

    Reference reconstruction

    Bv40, 0.6 mm showed highest SNR/CNR but greatest blooming

    Recommended protocol

    Bv64, 0.2 mm slices, 200 mm FOV, 512×512 matrix

    Source: Mergen V, Sartoretti TB, Baer-Beck M, Schmidt B, Petersilka M, Wildberger JE, Euler A, Eberhard M, Alkadhi H. Ultra-High-Resolution Coronary CT Angiography With Photon-Counting Detector CT: Feasibility and Image Characterization. Investigative Radiology. 2022;57(12):780-788. doi:10.1097/RLI.0000000000000897.

    ]]>