✓ Dural arteriovenous (AV) fistulas are thought to be acquired lesions that form in an area of thrombosis within a sinus. If the sinus remains completely thrombosed, venous drainage from these lesions occurs through cortical veins, or, if the sinus is open, venous drainage is usually into the involved sinus. Among 105 patients with dural A V fistulas evaluated over the the past 5 years, seven had a unique type of dural AV fistula in the superior sagittal, transverse, or straight sinus in which only cortical venous drainage occurred despite a patent involved sinus; the fistula was located within the wall of a patent dural sinus, but outflow was not into the involved sinus. This variant of dural AV fistulas puts the patient at serious risk for hemorrhage or neurological dysfunction caused by venous hypertension. Three patients presented with hemorrhage, one with progressive neurological dysfunction, one with seizures, and two with bruit and headaches. A combination of surgical and endovascular techniques was used to close the fistula while preserving flow through the sinus.
Stanley L. Barnwell, Van V. Halbach, Christopher F. Dowd, Randall T. Higashida, Grant B. Hieshima and Charles B. Wilson
Stanley L. Barnwell, Christopher F. Dowd, Richard L. Davis, Michael S. B. Edwards, Philip H. Gutin and Charles B. Wilson
✓ The cases of seven patients with intramedullary, cryptic vascular malformations of the spinal cord are reported. In all patients, the clinical course was progressive; a Brown-Séquard syndrome was the most common presenting symptom complex. Magnetic resonance (MR) imaging was performed in all patients. The pattern seen most often was a focus of high signal (on both T1- and T2-weighted MR images) surrounded by a larger zone of low signal (best seen on T2-weighted images), and was remarkably similar for all patients. Six patients underwent surgical exploration; removal of the lesions halted the progression of symptoms in five patients, and one patient had worsened sensory function after surgery. Motor function did not decrease postoperatively in any patient. The one patient who refused surgery has continued to decline neurologically. Histopathological examination of surgical specimens showed a cavernous malformation in one patient, a venous malformation in one, venous varices in two, and organizing hematomas in two; these findings are markedly different from those in previously reported cases of cryptic vascular malformations.
Results of combined endovascular and neurosurgical treatment in 16 patients
Stanley L. Barnwell, Van V. Halbach, Randall T. Higashida, Grant Hieshima and Charles B. Wilson
✓ Of the 88 patients evaluated for symptomatic dural arteriovenous (AV) fistula over the past 8 years, 16 had large or complicated lesions that could not be treated with standard transvascular approaches or in which such treatment had been unsuccessful. Eleven fistulas were located in the transverse sinus, two in the cavernous sinus, two in the straight sinus, and one in the falx-tentorial region near the vein of Galen. The patients were treated with a combination of endovascular and neurosurgical techniques. Fourteen patients underwent preoperative transarterial embolization; this procedure closed the fistula in one patient. In the remaining 15 patients, surgery was performed to provide access to the fistula for embolization from either the venous or the arterial side, or for excision of the fistula. Transvenous embolization completely obliterated the fistula in seven of nine patients; the fistulas were embolized incompletely through the feeding arteries in two patients; and complete surgical resection of the lesion was accomplished in four patients. Complications related to venous occlusion occurred in two patients and one patient suffered communicating hydrocephalus that was effectively treated by shunting. There were no deaths. The results suggest that combined endovascular and neurosurgical techniques are a safe and effective means for the treatment of selected complex dural AV fistulas.
Michael C. Brodsky, William F. Hoyt, Stanley L. Barnwell and Charles B. Wilson
✓ The authors describe the case of a young man who presented with a central scotoma in one eye and a temporal hemianopsia in the other. Magnetic resonance imaging showed distinctive bilobed thickening of the chiasm and a “potbelly” expansion of the contiguous optic nerves. The distal portions of the intracranial optic nerves appeared normal. At craniotomy, incision of the lamina terminalis exposed intraventricular craniopharyngioma with anterior extension into the chiasm and proximal optic nerves. Partial resection of the tumor restored normal vision.