The Yield of Repeat Angiography in Angiography-Negative Spontaneous Subarachnoid Hemorrhage

Abstract

Objective Despite the technological advancement in imaging, digital subtraction angiography (DSA) remains gold standard imaging modality for spontaneous subarachnoid hemorrhage (SAH). But even after DSA, around 15% of SAH remains elusive for the cause of the bleed. This is an institutional review to solve the mystery, "when is second DSA really indicated?" Methods In a retrospective review from January 2015 to December 2017, we evaluated cases of spontaneous SAH with initial negative DSA with repeat DSA after 6 weeks to rule out vascular abnormality. The spontaneous SAH was confirmed on noncontrast computed tomography (NCCT) and divided into two groups of perimesencephalic SAH (PM-SAH) or nonperimesencephalic SAH (nPM-SAH). The outcome was assessed by a modified Rankin's score (mRS) at 6 months postictus. Results During the study period, we had 119 cases of initial negative DSA and 98 cases (82.3%) underwent repeat DSA after 6 weeks interval. A total of 53 cases (54.1%) had PM-SAH and 45 cases (45.9%) had nPM-SAH. Repeat DSA after 6 weeks showed no vascular abnormality in 53 cases of PM-SAH and in 2 (4.4%) out of 45 cases of nPM-SAH. At 6 months postictus, all cases of PM-SAH and 93% of nPM-SAH had mRS of 0. Conclusion We recommend, a repeat DSA is definitely not required in PM-SAH, but it should be done for all cases of nPM-SAH, before labeling them as nonaneurysmal SAH. Although the overall outcome for nonaneurysmal spontaneous SAH is better than aneurysmal SAH, nPM-SAH has poorer eventual outcome compared to PM-SAH.

Keywords: SAH; angiography negative; outcomes; perimesencephalic SAH; repeat DSA.

Fig. 1

A 39-year-old woman presented with headache and vomiting. ( A ) NCCT brain axial image showing predominantly left Sylvian fissure SAH. ( B ) DSA image on the anteroposterior projection of left ICA injection showing normal filling of both ACA and MCA without any obvious vascular abnormality. ( C ). Magnified image of repeat DSA at 6 weeks on the anteroposterior projection of left ICA injection showing normal filling of ACA and MCA. A bleb is seen on the anterior temporal artery (arrow). ACA, anterior cerebral artery; DSA, digital subtraction angiography; ICA, internal cerebral artery; MCA, middle cerebral artery; NCCT, noncontrast computed tomography; SAH, subarachnoid hemorrhage.

Fig. 2

A 58-year-old woman presented with thunder clapping headache. ( A ) NCCT brain axial image showing diffuse SAH involving Anterior Inter-hemispheric and bilateral Sylvian SAH. ( B ) DSA image on a lateral projection of left ICA injection showing normal filling of both ACA and MCA without any obvious vascular abnormality.( C ) Magnified image of repeat DSA at 6 weeks on a lateral projection of left ICA injection showing a bleb on the ICA just proximal to the origin of the ophthalmic artery (arrow). ACA, anterior cerebral artery; DSA, digital subtraction angiography; ICA, internal cerebral artery; MCA, middle cerebral artery; NCCT, noncontrast computed tomography; SAH, subarachnoid hemorrhage.

Fig. 3

A 42-year-old man presented with once in a lifetime severe headache. NCCT axial brain image showing left-sided perimesencephalic SAH. NCCT, noncontrast computed tomography; SAH, subarachnoid hemorrhage.