Figure 1
Schematic representation of the detector design of an energy integrating detector CT (A) and a photon‑counting CT (B).
Figure 2
Post‑traumatic CT imaging of the wrist in a 55‑year‑old male. (A) Initial post‑trauma CT imaging performed on a Siemens SOMATOM Definition Flash CT. (B) Two months later, the patient was scanned on the Siemens NEAOTOM Alpha in ultra‑high resolution enabling better depiction of bone microarchitecture at a significant lower radiation dose (CTDIvol of 10.4 mGy on PCCT compared to CTDIvol of 19.71 mGy on EID CT).
Table 1
Summary of the clinical applications of PCCT imaging.
| APPLICATION | CLINICAL CONTEXT | ADVANTAGES |
|---|---|---|
| Musculoskeletal pediatric imaging | Trauma, infection, congenital diseases, and bone/soft tissue tumors | Improved imaging at a significant dose reduction |
| Metal artifact reduction | Evaluation of prostheses/screws and periprosthetic fractures | Reduced artifacts enhancing diagnostic accuracy |
| Bone marrow edema maps | Trauma and insufficiency fractures | Inherent spectral data allows for visualization of bone marrow edema associated with fractures |
| Crystal arthropathy | Evaluation of crystal arthropathies | Improved detection and differentiation of crystal arthropathies |
| Multiple myeloma | Detection of osteolytic bone lesions | Significant radiation dose reduction and potential assessment of activity level of lesions |
| Cartilage and subchondral bone imaging | Osteoarthritis | Improved evaluation of cartilage and subtle subchondral lesions |
| Bone mineral density | Opportunistic osteoporosis screening and prediction of fracture risk | BMD measurement and fracture risk assessment on routine PCCT scans |
| Soft tissue | Evaluation of soft tissue injury | Possibility of evaluating soft tissue injury |
Figure 3
A 13‑year‑old female with an osteosarcoma in the right proximal tibia manifesting as an osteolytic lesion (white arrowhead) with cortical disruption of the lateral wall of the proximal tibia and the medial wall of the proximal fibula (long white arrow) and a notable extra‑ossous component invading the anterior muscle compartment (short white arrow) with mineralization in the soft tissue component (black arrowhead). Furthermore, a subtle periosteal reaction at the anterior wall of the proximal fibula is noted (black arrow).
Figure 4
PCCT image post scaphoid screw fixation for a scaphoid fracture in a 45‑year‑old male with excellent metal artifact reduction using tin filtration and IMAR, allowing for visualization of trabecular structure in the thread of the screw at a CTDIvol of 15.5 mGy.
Figure 5
An 81‑year‑old female consulting the emergency department after trauma with an implant fracture of the acetabular cup of the hip prosthesis. (A) Coronal slice with IMAR showing an implant fracture (white arrowhead) on a Siemens SOMATOM Definition Flash. (B) An additional IMAR PCCT scan was performed on the Siemens NEAOTOM Alpha to enhance characterization of the implant fracture (white arrowhead) highlighting the improved spatial resolution and metal artifact reduction at a lower radiation dose compared to EID CT (CTDIvol of 11.8 mGy vs 13.3 mGy).
Figure 6
An 81‑year‑old woman consulted the emergency department with right hip pain after a low‑energy trauma. (A) No clear fracture was visible on the grayscale images on the PCCT. (B) However, the bone marrow edema map shows intertrochanteric edema (white arrowheads), suggestive of a fracture. (C) MRI the following day confirms an intertrochanteric fracture (white arrows).
Figure 7
A 76‑year‑old female presenting with pain and redness in the forefoot. (A) A small dense area in the soft tissue surrounding the distal part of the medial cuneiform bone (white arrowhead) on the grayscale CT images, suggestive of gout. (B) Post‑processing images using the gout application in SyngoVia highlight the monosodium urate crystals in green (white arrow).
Figure 8
Ultra‑high resolution (UHR) PCCT scan in a 74‑year‑old woman with osteoarthritis of the knee. The UHR allows for meticulous depiction of the trabecular structure as well as the secondary bone remodeling with sclerosis of the medial tibial condyle (white arrowhead) and osteophyte formation bilaterally (white arrows).