Cerebral Angiography Can Demonstrate Changes in Collateral Flow During Induced Hypertension

AbstractA 52-year-old woman with a large left-hemispheric stroke was transferred to our hospital for possible endovascular treatment. The patient underwent a cerebral angiogram at 7 hours after symptom onset with intent to treat and was found to have occlusion of the proximal M1-segment of the left middle cerebral artery (MCA). At that time it was felt that this was a high-risk patient for mechanical clot retrieval and it was decided to treat her with induced hypertension. The diagnostic catheter was left in place in the left internal carotid artery (ICA) and hypertension was induced in the angiography suite by means of an infusion of neosynephrine. Ten minutes after the goal blood pressure levels had been reached, a repeat left ICA injection was performed, which demonstrated more extensive collateralization of the MCA territory from anterior cerebral artery branches. Mean transit times (MTT) for the left ICA circulation improved from 9.5 seconds prior to induced hypertension to 6.0 seconds. The neosynephrine infusion was continued for a total of 24 hours and the patient showed neurological improvement. We suggest that induced hypertension led to the improved collateralization to the left MCA as evidenced by the improved MTT and augmentation of leptomeningeal collaterals, which in turn led to the patient's clinical improvement

Computed tomographic angiography versus digital subtraction angiography for the postoperative detection of residual aneurysms: a single-institution series and meta-analysis.

BACKGROUND: Computed tomographic angiography (CTA) has recently emerged as a non-invasive alternative to digital subtraction angiography (DSA) for the detection of residual cerebral aneurysms (RA). OBJECTIVE: To compare the diagnostic accuracy of CTA with the current \u27gold standard\u27, DSA, in the postoperative detection of RA. METHODS: Patient data from this single institution were prospectively gathered, and imaging results retrospectively blinded and analyzed. Between 2001 and 2005 eligible patients received microsurgical repair of cerebral aneurysms and were evaluated postoperatively by DSA and CTA. These single-institutional data were compiled with qualified studies published from 1997 to 2009, and a meta-analysis was performed. RESULTS: This institutional series reports sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of 100%. Eleven studies met the inclusion criteria for the meta-analysis. A total of 427 patients with 513 aneurysms were included, with 61 RA detected by DSA and 40 detected by CTA. Unweighted analysis resulted in pooled sensitivity of 73.8%, specificity of 96.3%, PPV of 91.0% and NPV of 86.1%. Stratified analysis of studies using 16-slice CTA versus 2D DSA reported pooled sensitivity of 92.6%, specificity of 99.3%, PPV of 95.8%, and NPV of 97.8%. CONCLUSIONS: This meta-analysis supports CTA as an acceptable modality for postoperative detection of RA, although DSA remains the gold standard. By implementing multidetector CTA technology in experienced centers, the sensitivity and specificity of CTA may approach that of traditional DSA for detecting RA. As a cost-effective, non-invasive modality, CTA is a promising alternative to DSA for initial and long-term evaluation of RA