Purpose: Routine CT Angio (CTA) scans of the head commonly include a non-contrast scan to rule out hemorrhage and an arterial phase scan for vessel delineation. Our purpose was to assess the contribution of the venous phase scan by evaluating the conspicuity of lesions found on tri-phasic CTA studies of patients with apparent neoplastic disease.
Materials and Methods: Retrospective review of reports of consecutive CTA scans of the head of patients with neurological signs, between September 2011 and April 2017, was performed. Reports containing neoplastic findings were selected for review. All scans were performed on 64 and 256 slice CT scanners (Philips, Netherlands). Pre-contrast, arterial and venous phase images were evaluated by a neuroradiologist for neoplastic disease. Lesions were graded on a 4 step scale of conspicuity (0-non-detectable, 1- barely detectable, 2-detectable, 3-easily detectable). Multiple detected lesions were grouped together if their conspicuity was identical.
Results: 14 patients were identified with neoplastic disease and 23 separate lesions were evaluated. On the non-contrast and arterial phase scans 48% of lesions (n=11) were non-detectable. 30% (n=7) and 35% (n=8) were barely detectable, respectively. Only 17% (n=4) were detectable on both scans and 4% (n=1) were easily detected on the non-contrast scan. On the venous phase scans 74% (n=17) of the lesions were easily detected and 26% (n=6) were detected. None of the lesions were barely detectable or undetectable on the venous phase.
Conclusion: In a small number of cases, adding a venous phase scan of the head, during routine CTA scans in patients with neurological signs, greatly increases conspicuity of neoplastic lesions, compared to the non-contrast and arterial phase scans.
