Improved Diagnostic Certainty of Photon-Counting CT Myelography Compared with Energy-Integrating CT for CSF-Venous Fistulas in Spontaneous Intracranial Hypotension

<h3>BACKGROUND AND PURPOSE:</h3> Photon-counting detector CT myelography (PCD-CTM) offers higher spatial resolution than energy-integrating detector CT myelography (EID-CTM), and preliminary studies have shown improved CSF-venous fistula (CVF) conspicuity in spontaneous intracranial hypotension (SIH). We compared CVF detection between PCD-CTM and EID-CTM using the Duke CSF-Venous Fistula Confidence Score (DCCS) in a large SIH cohort. <h3>MATERIALS AND METHODS:</h3> This retrospective study included 628 CTM examinations in 456 patients (63.2% women; mean age, 58.0 years) evaluated for SIH (2020–2025). Two neuroradiologists scored each examination using the DCCS (0 to 3) with consensus adjudication. CVF detection (DCCS ≥2) was compared between PCD-CTM (<i>n</i> = 148) and EID-CTM (<i>n</i> = 480). <h3>RESULTS:</h3> PCD-CTM demonstrated a significant shift toward higher DCCS scores compared with EID-CTM (<i>P</i> = .006), with 66% greater odds of a higher DCCS category on ordinal logistic regression (OR 1.66; 95% CI, 1.17 to 2.36; <i>P</i> = .005). Overall CVF detection was 63.1% (396/628), numerically higher for PCD-CTM (69.6% vs 61.0%; <i>P</i> = .07). <h3>CONCLUSIONS:</h3> PCD-CTM was associated with significantly greater diagnostic certainty compared with EID-CTM as measured by the DCCS. These findings support adopting PCD technology for CVF evaluation.