Delayed traumatic intracranial aneurysms: literature review and case series

Traumatic intracranial aneurysm (TICA) is a rare and aggressive pathology that requires prompt treatment. Nevertheless, early vascular imaging following head trauma may yield falsely negative results, underscoring the importance of subsequent imaging within the first week to detect delayed TICAs. This study aims to report our experience with delayed TICAs and highlight the clinical importance of repeated angiographic screening for delayed TICAs. In this retrospective analysis, we evaluated patients managed for a TICA at a tertiary care teaching institution over the last decade. Additionally, we conducted a systematic review of the literature, following the PRISMA guidelines, on previously reported TICAs, focusing on the time lag between the injury and diagnosis. Twelve delayed TICAs were diagnosed in 9 patients. The median time interval from injury to diagnosis was 2 days (IQR: 1-22 days), and from diagnosis to treatment was 2 days (IQR: 0-9 days). The average duration of radiological follow-up was 28 +/- 38 months. At the final follow-up, four patients exhibited favorable neurological outcomes, while the remainder had adverse outcomes. The mortality rate was 22%. Literature reviews identified 112 patients with 114 TICAs, showcasing a median diagnostic delay post-injury of 15 days (IQR: 6-44 days), with 73% diagnosed beyond the first week post-injury. The median time until aneurysm rupture was 9 days (IQR: 3-24 days). Our findings demonstrate acceptable outcomes following TICA treatment and highlight the vital role of repeated vascular imaging after an initial negative computed tomography or digital subtraction angiography in excluding delayed TICAs.