Volume: 4 Issue: 3
Year: 2016, Page: 17-21,
Introduction: Normal variants of the cerebral circulation are common, and most such variants can be identified at 128 slice CT angiography.
Objectives:The rationale of this study was to evaluate whether Rupatadine or Fexofenadine was better in the treatment of allergic rhinitis.
Materials and Methods :An observational study to find out the normal variants of cerebral circulation in 120 patients who underwent CT cerebral angiogram for various causes during the period of January 2014 to July 2015.
Results:Out of 120 patients, 0.8% had fenestrations of anterior cerebral artery, 0.8% had fenestrations of anterior communicating artery, 26.7% had hypoplasia of A1 segment of anterior cerebral artery, 0.8 % had absent anterior communicating artery, 17.5% had early branching of middle cerebral artery,17.5% had fetal origin of the posterior cerebral artery , 1.7 % had hypoplasia of the internal carotid artery. Out of all variants, hypoplasia of A1 segment was most common and other common variants were Early branching of middle cerebral artery and Fetal origin of the posterior cerebral artery .
Conclusion:Accurate detection and characterization of variation of cerebral circulation is an essential prerequisite for surgical treatment planning. The introduction of 128 slice CT scanner has greatly advanced the role of CTA in three dimensional analysis variation of cerebral circulation of particularly in places where digital subtraction angiography (DSA) is not available. CTA is highly sensitive and specific and can replace DSA for diagnostic purposes.
Keywords: CT angiography, fenestration, variations of circle of willis, persistent carotid and basilar artery anastomoses.
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