Charles P. Hodge

Cerebral Blood Flow in Superficial Temporal Artery to Middle Cerebral Artery Anastomosis

Anastomosis of the superficial temporal artery (STA) to a branch of the middle cerebral artery (MCA) has become increasingly popular since its introduction 11 years ago.3, 20 The efficacy of this procedure in preventing cerebral infarction, however, has yet to be proven despite encouraging clinical results.2,6,15,21 The definition of its role in the treatment of cerebral ischemia will depend partly upon the results of cerebral blood flow (CBF) studies. A few studies1,13,14 demonstrating improvement in regional cerebral blood flow (rCBF) have been reported, but our knowledge of the changes in the cerebral circulation in patients undergoing STA-MCA anastomosis remains limited. The object of this investigation was to provide further information about these changes by studying CBF in a group of patients before, during, and after surgery.

Epicerebral Angiography by Fluorescein during Craniotomy

Publisher Summary In previous reports we have described the use of radio-active isotopes and Coomassie Blue dye injected by internal carotid catheter for analysis of the regional blood flow in the epicerebral circulation (the pial arteries and veins and the cortical capillary bed) during craniotomyl. This method allows for the comparison of quantitative radioisotopic blood flow curves directly with the anatomical pattern of the normal and abnormal vasculature on the surgically exposed brain. This approach has provided information on changes in blood flow in angiomas and adjacent cortex before and after obliteration of arterial feeders, or after arterial manipulation during clipping of aneurysms, and on abnormal flow rates in tumours with arterio–venous shunts. It should be emphasized that this direct comparison of the anatomy and rheology of the cerebral circulation directly from the surface of the brain offers many advantages over the technique of external monitoring by radio-isotopes of cerebral blood flow, where the details of the cerebral microcirculation have not been available. In summary, a new method of fluorescein angiography for demonstration of the epicerebral circulation during craniotomy provides for rapid sequential recording of the flow in the pial and cortical vessels. The advantages of the method include the display of the small vessels of the brain not seen on X-ray angiography so that examination of the cerebral microcirculation in vivo now becomes possible. Secondly, it allows the neurosurgeon to study the anatomical pattern of the epicerebral vessels in man under a wide variety of abnormal conditions.

Experimental Cerebral Revascularization Studied by 85Kr Clearance and Fluorescein Angiography After 24 Hours of Permanent Occlusion of the Middle Cerebral Artery in Dogs

In spite of encouraging clinical results,1,17 the definitive role of extra-intracranial bypass in the prevention and treatment of ischemic cerebrovascular disease needs to be further substantiated. Still required are information from clinical cooperative controlled studies and further experimental analysis of the metabolic and hemodynamic changes as well as of the circulatory patterns that follow revascularization in acute and chronic ischemia.