CVD-Aneurysm, Vascular Malformation, and SAH MRA Head MR angiography (MRA) head for the evaluation of intracranial aneurysm demonstrated a pooled sensitivity of 95% and specificity of 89% in one meta-analysis [21]. Diagnostic accuracy is increased, including for aneurysms >5 mm in size and at 3T scanner strength [21,22]. The decrease in specificity, when compared with CTA, is reported to have false-positive cases related to normal vascular variants of infundibular origin of vessels and vessel loops [23]. Limitations of MRA head include required safety screening and relatively long acquisition time in urgent clinical scenarios. MRA Neck There is no relevant literature to support the use of MRA neck in the evaluation of known acute SAH. MRA neck may be useful for potential treatment planning, but preference will be individual or site specific. MRI Head Perfusion There is no relevant literature to support the use of MRI head perfusion in the evaluation of known acute SAH. MRI Head Although there is no relevant literature to support the use of MRI head in the evaluation for a vascular source of known acute SAH, several studies evaluated the use of MRI head in predicting clinical outcomes. Patients with acute poor-grade SAH and diffusion-weighted imaging positive findings on MRI head had a less favorable long- term outcome when compared with patients without diffusion-weighted imaging positive findings [24,25]. MRV Head There is no relevant literature to support the use of MR venography (MRV) head in the evaluation of known acute SAH. US Duplex Doppler Carotid Artery There is no relevant literature to support the use of carotid artery ultrasound (US) duplex Doppler in the evaluation of known acute SAH. US Duplex Doppler Transcranial There is no relevant literature to support the use of US transcranial with duplex Doppler (TCD) in the evaluation of known acute SAH. Variant 2: Suspected cerebral vasospasm. Initial imaging.
Cerebrovascular Diseases Aneurysm Vascular Malformation and Subarachnoid Hemorrhage PCAs. CVD-Aneurysm, Vascular Malformation, and SAH MRA Head MR angiography (MRA) head for the evaluation of intracranial aneurysm demonstrated a pooled sensitivity of 95% and specificity of 89% in one meta-analysis [21]. Diagnostic accuracy is increased, including for aneurysms >5 mm in size and at 3T scanner strength [21,22]. The decrease in specificity, when compared with CTA, is reported to have false-positive cases related to normal vascular variants of infundibular origin of vessels and vessel loops [23]. Limitations of MRA head include required safety screening and relatively long acquisition time in urgent clinical scenarios. MRA Neck There is no relevant literature to support the use of MRA neck in the evaluation of known acute SAH. MRA neck may be useful for potential treatment planning, but preference will be individual or site specific. MRI Head Perfusion There is no relevant literature to support the use of MRI head perfusion in the evaluation of known acute SAH. MRI Head Although there is no relevant literature to support the use of MRI head in the evaluation for a vascular source of known acute SAH, several studies evaluated the use of MRI head in predicting clinical outcomes. Patients with acute poor-grade SAH and diffusion-weighted imaging positive findings on MRI head had a less favorable long- term outcome when compared with patients without diffusion-weighted imaging positive findings [24,25]. MRV Head There is no relevant literature to support the use of MR venography (MRV) head in the evaluation of known acute SAH. US Duplex Doppler Carotid Artery There is no relevant literature to support the use of carotid artery ultrasound (US) duplex Doppler in the evaluation of known acute SAH. US Duplex Doppler Transcranial There is no relevant literature to support the use of US transcranial with duplex Doppler (TCD) in the evaluation of known acute SAH. Variant 2: Suspected cerebral vasospasm. Initial imaging.