Introduction: CT angiography (CTA) is being increasingly used as first-line vascular imaging modality in patients with intracranial hemorrhage (ICH). We sought to determine the real-world diagnostic accuracy of CTA in a cohort of ICH patients worked up and managed aggressively by a single dual vascular-endovascular neurosurgeon over a period of 15 months.
Methods: All patients with nontraumatic ICH managed by the author between March 2013 and May 2014 were identified from a prospectively maintained database. Patients with typical hypertensive ICH were excluded. Patient demographics, ICH pattern, CTA and DSA findings were recorded.
Results: Of 74 patients, 13 underwent ICH evacuation and/or aneurysm clipping, based on CTA alone (n=11) or without vascular imaging (n=2). Another 2 patients underwent DSA only. The remaining 59 patients, who underwent both CTA and DSA, constitute the study population. These were 32 women and 27 men with a mean age of 50 years (18-83). ICH pattern was: aneurysmal SAH in 37, PMSAH in 8, intraparenchymal in 11, intraventricular in 2, and subdural in 1. The overall yield of vascular imaging was 62.7% (37/59), including 29 saccular aneurysms, 4 dissecting aneurysms, and 4 microAVMs. The accuracy of DSA was 100%. The specificity and positive predictive value of CTA were equally 100%. However, the sensitivity and negative predictive value of CTA were only 89.2% and 84.6%, respectively. CTA missed 4 lesions (2 dissecting aneurysms, 1 microAVM, 1 small saccular aneurysm). Of 8 patients with PMSAH, 3 (37.5%) had a vascular lesion (1 vertebrobasilar dissection, 1 cerebellar microAVM, 1 basilar tip aneurysm), 2 of which were missed by CTA.
Conclusions: DSA may identify a lesion in up to 15% of patients with ICH and negative CTA. Excessive reliance on CTA can be potentially hazardous. Neurosurgeons should have a very low threshold for obtaining DSA in patients with ICH, including those with PMSAH.
Patient Care: Help improve the rate of detection of vascular lesions in patients with ICH and SAH, by lowering the threshold for catheter angiography and promoting an aggressive approach to the workup of these patients. Early identification and treatment of these lesions can improve patient outcomes by reducing the risk of rehemorrhage.
Learning Objectives: By the conclusion of this session, participants should be able to:
1. Understand the limitations of CTA in the vascular workup of patients with nontraumatic ICH and/or SAH.
2. Recognize that up to 15% of patients with ICH and a negative CTA may be found to harbor a vascular lesion on DSA.
3.Recognize that the lesions most commonly missed by CTA are: small saccular aneurysms, small AV shunt lesions (microAVM, AVF), and arterial dissections.