PCCT of the spine provided higher sharpness and lower image noise than EID-CT at a clearly lower radiation dose.
In patients with metallic implants, 130 keV monoenergetic reconstructions further improved image quality, artifact reduction, and diagnostic confidence compared with standard PCCT reconstructions.
PCCT appears particularly valuable for postoperative spine imaging, where metal artifact reduction and lower dose are highly relevant.
Access publication
Figure 4. Image example of an 85-year-old patient with post-surgical CT after spinal fusion due to traumatic fracture and suspected screw loosening (window center 500 HU, window width 2000 HU). Images depict an axial slice at the height of the 5th cervical vertebra. EID-CT shows severe artifacts caused by metallic implants resulting in a substantially impaired image quality and reduced diagnostic confidence. Screw loosening was suspected in the left pedicle (arrow). After treatment of a delayed wound healing, follow-up CT imaging was performed on a PCCT after interim external immobilization of the neck. PCCTstd shows significantly reduced artifacts and better depiction of the bone resorption and also reveals loosening of the right screw (arrow). PCCT 130 keV reconstruction shows almost no artifacts and clearly depicts the bone resorption around both screws (arrows). EID-CT = energy-integrating CT; PCCTstd = photon-counting CT; PT-CT130 keV PC-CT with monoenergetic reconstructions at 130 keV
Protocol
Detail | Value |
|---|
Scanner | NAEOTOM Alpha |
Scan area | Spine |
Scan mode | QuantumPlus |
Tube voltage [kV] | 120 |
Effective mAs [mAs] | 60 |
IQ level | IQ 85 |
Dose modulation | CARE Dose4D |
CTDIvol [mGy] | 8.83 mean |
Effective dose [mSv] | 1.64 mean |
Rotation time [s] | 0.5 |
Pitch | 0.8 |
Slice collimation [mm] | 144 × 0.4 |
Slice width [mm] | 2 |
Reconstruction increment [mm] | 2 |
Reconstruction kernel | Br64 standard bone kernel |
Iterative reconstruction | QIR 2 |
keV level [keV] | 65 standard |
Contrast agent | none |
Rau A, Straehle J, Stein T, Diallo T, Rau S, Faby S, Nikolaou K, Schoenberg SO, Overhoff D, Beck J, Klingler JH, Bamberg F, Weiss J. Photon-Counting Computed Tomography (PC-CT) of the spine: impact on diagnostic confidence and radiation dose. Eur Radiol. 2023;33:5578-5586. doi:10.1007/s00330-023-09511-5
