Photon-Counting Detector CT Improves Visualization of the Normal Carotid Body Compared with Energy-Integrating Detector CT
In brief
Photon-counting CT visualizes carotid bodies in 100% versus 78% with standard CT
In a head-to-head comparison of 37 patients, photon-counting detector CT identified every carotid body (100%) while conventional energy-integrating CT missed about one-quarter (78%). Radiologists rated image quality markedly higher on the photon-counting scans. Knowing the normal size and shape may help avoid mistaking these tiny structures for early paragangliomas, though larger studies are needed to confirm clinical impact.
- Journal
- AJNR. American journal of neuroradiology (Q1)
- Published
- 3 September 2026
- Study design
- Cohort / observational study
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Michael G LaVere, Paul Farnsworth, Lifeng Yu, Blake Kassmeyer, Girish Bathla, Pranjal Rai, et al.
- PMID
- 42692786
- DOI
- 10.3174/ajnr.A9619
Why clinicians should know about it
- Picked for Medical Physics (top studies of the week, 6 September 2026): PCD-CT vs EID-CT improves carotid body visualization
Abstract
BACKGROUND AND PURPOSE: The carotid bodies are small chemoreceptor organs at the carotid bifurcation. Their depiction on conventional CT angiography is inconsistent, with reported detection rates on energy-integrating detector CT (EID-CT) of 62% to 91%. This study evaluates whether photon-counting detector CT (PCD-CT) improves carotid body visualization and describes their normal imaging appearance. MATERIALS AND METHODS: This retrospective study included 37 patients who underwent both PCD-CT and EID-CT head and neck angiography, yielding 74 carotid bifurcations. Two neuroradiologists, reading in consensus, recorded whether each carotid body was definitively identifiable on each modality and rated relative image quality on a 5-point comparative Likert scale. Morphologic measurements were obtained from PCD-CT. Likert scores were analyzed with a linear mixed-effects model with a random intercept for patient; identification was compared with the McNemar test. RESULTS: Reader preference strongly favored PCD-CT (median Likert score, 5.0 [IQR, 4.0-5.0]; mixed-effects mean, 4.6; 95% CI, 4.4-4.8; P < .001). Carotid bodies were identified in all 74 bifurcations (100%) on PCD-CT versus 58 of 74 (78.4%) on EID-CT (P < .001); at least one was missed on EID-CT in 12 of 37 patients (32%). Carotid bodies were ellipsoid in 71 of 74 (95.9%), with mean anteroposterior, transverse, and superoinferior dimensions of 2.0 ± 0.7, 2.1 ± 0.7, and 2.9 ± 1.1 mm, and a median volume of 5.9 mm³ (IQR, 3.8-8.5). CONCLUSIONS: PCD-CT reliably visualizes normal carotid bodies that are frequently missed on conventional EID-CT. Familiarity with their normative appearance may reduce mischaracterization as early paraganglioma and provides a foundation for volumetric research into the carotid body's role in systemic disease.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.