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Spontaneous brain hemorrhage accounts for about 10% of all strokes and is fatal in about 50% of the cases. Its incidence, in contrast to other types of strokes, has not declined. Hypertension accounts for about half of these hemorrhages; the rest are due to tumors, aneurysms and vascular malformations, inflammatory and degenerative vasculopathies and hematologic and iatrogenic disorders of coagulation. In some patients no cause is ever found. Hypertensive brain hemorrhage occurs in the deep gray nuclei of the hemispheres, the cerebellum, and the pons and results in specific clinical syndromes depending on the location. Computerized tomography has revolutionized the diagnosis of brain hemorrhage and is resulting in the development of rational criteria for medical and surgical management of these lesions. Intensive medical therapy guided by clinical status and continuous monitoring of ICP may improve outcome. Surgical removal of the hematoma is indicated in lobar and putaminal hemorrhages when the patient is deteriorating in spite of vigorous medical therapy. In addition most large (greater than 3 cm) cerebellar hemorrhages, as well as smaller cerebellar hemorrhages that result in significant brain stem compression should be evaluated. The roles of intensive medical therapy, elective late surgery and of immediate operation in improving eventual functional outcome need to be investigated further.

A technique for achieving a combined pterional (subfrontal) and anterior temporal exposure for aneurysms of the upper basilar complex is described. The technique is not new, but it does involve several modifications not previously described. A standard pterional skin incision that extends below the zygoma just anterior to the tragus is used. The skin flap is separated from the temporal fascia down to the fat pad over the zygoma; at this point, the superficial layer of the temporalis fascia is incorporated and retracted with the skin flap to expose the zygomaticofrontal process and the zygomatic arch. The muscle is cut anteriorly and inferiorly and is retracted posteriorly over the ear. The bone flap includes the anterior temporal squama down to the temporal floor anteriorly. The pterion and the sphenoidal wings are drilled so as to expose completely the dura over the anterior temporal pole. After opening the dura on a flap centered on the sylvian fissure, the medial cisterns are opened widely and the fissure is opened all the way to the middle cerebral bifurcation. Posterolateral temporal retraction and, when necessary, subpial resection of the anteromedial portion of the uncus enhance the exposure posterolateral to the oculomotor nerve. The advantages of this combined approach are as follows: it combines the more anterior angle of vision offered by the pterional approach with the lateral line of vision offered by the subtemporal approach; it eliminates the need for temporal lobe elevation and it allows simultaneous clipping of other aneurysms of the ipsilateral anterior circle of Willis; and it also reduces the frequency and severity of oculomotor palsy, when compared with the subtemporal approach.

No abstract

Cerebral vasospasm is a biphasic event resulting in most cases in an irreversibly constricted cerebral blood vessel. The major initiator of vasoconstriction is subarachnoid hemorrhage (SAH) or trauma. Several animal models have been developed but none approximates the pathological sequellae seen in man after SAH. We have refined a dog SAH model which possesses many of the physiological and ultrastructural features seen in man after SAH induced vasospasm and report some clinically relevant findings.