✓ The case of an 11-year-old boy is reported in whom two intramedullary lesions developed at the thoracic-cervical and thoracic-lumbar junctions 2½ years after resection and irradiation of a medulloblastoma in the posterior fossa. There was no evidence of subarachnoid spread of the tumor. Magnetic resonance imaging was used to localize these lesions, and provided much better diagnostic information than either computerized tomography scans or myelograms.
Stanley L. Barnwell and Michael S. B. Edwards
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.
Jordi X. Kellogg, Todd A. Kuether, Michael A. Horgan, Gary M. Nesbit and Stanley L. Barnwell
With greater understanding of the pathophysiological mechanisms by which carotid artery-cavernous sinus fistulas occur, and with improved endovascular devices, more appropriate and definitive treatments are being performed. The authors define cartoid cavernous fistulas based on an accepted classification system and the signs and symptoms related to these fistulas are described. Angiographic evaluation of the risk the lesion may pose for precipitating stroke or visual loss in the patient is discussed. The literature on treatment alternatives for the different types of fistulas including transvenous, transarterial, and conservative management is reviewed.
Gary M. Nesbit, Wayne M. Clark, Oisin R. O'Neill and Stanley L. Barnwell
✓ This report covers a series of four patients with acute cervical carotid occlusion and profound neurological deficits who were treated with intracranial intraarterial thrombolysis. All of the patients presented with arm plegia with variable leg involvement and two of them had global aphasia. Angiography identified occlusion of the proximal internal carotid artery (ICA) in each case and intracranial thromboembolus of the supraclinoid ICA and/or its branches.
Catheter navigation through the occluded ICA segment was straightforward in three patients and somewhat difficult in one patient with an 80% ICA stenosis. Intraarterial urokinase infusion along with mechanical clot disruption was performed at the clot site in the middle cerebral artery, supraclinoid ICA, and/or anterior cerebral artery. All patients had recanalization of the treated artery after urokinase infusion. Antegrade flow through the ICA was reestablished in two patients, and good collateral filling across the anterior communicating artery was established in the other two. All patients had major pretreatment deficits (mean National Institutes of Health (NIH) Stroke Score 24 ± 4) with significant improvement noted at 3 months posttreatment (NIH Stroke Score 7 ± 6; p = 0.03). Two patients made a dramatic early recovery. Postprocedure computerized tomography revealed no abnormality in one and asymptomatic basal ganglia high density from repeated local contrast injections in two patients.
On the basis of their findings in this small study group the authors suggest that catheter navigation through a presumably occluded carotid artery is feasible and possibly effective in thrombolytic therapy of intracranial thrombolysis. Further study with clinical trials is necessary to determine the safety and efficacy of this technique.
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.
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.
Mark J. Stephan, Gary M. Nesbit, Melinda L. Behrens, Malcolm A. Whitaker, Stanley L. Barnwell and Nathan R. Selden
✓Hereditary hemorrhagic telangiectasia ([HHT] or Osler-Weber-Rendu syndrome) can manifest as sudden onset of epistaxis or neurological deficit in a child with characteristic mucocutaneous telangiectasias or as an asymptomatic bruit with or without overlying cutaneous vascular lesions. The authors present a case study of a pediatric patient with HHT in whom a screening computerized tomography (CT) scan of the chest revealed an asymptomatic arteriovenous malformation (AVM) of the spine.
An 18-month-old child with a strong family history of HHT, including fatal central nervous system (CNS) hemorrhage and pulmonary AVMs, presented with a cutaneous telangiectasia of the pinna. The child was subsequently screened for potentially morbid pulmonary and CNS AVMs by using chest CT scanning and brain magnetic resonance (MR) imaging. A spinal MR image revealed a perimedullary macro-AVF (MAVF) resulting in a large venous varix within the parenchyma of the thoracic spinal cord. A transarterial embolization of the fistula was performed using N-butyl cyanoacrylate and ethiodol. Postembolization angiography confirmed obliteration of the fistula, and MR imaging revealed thrombosis and reduction in size of the venous varix. There were no neurological sequelae due to the treatment.
In families with HHT and a high risk of sudden severe morbidity or death from undisclosed pulmonary or CNS AVMs, screening chest CT scanning and CNS MR imaging should be considered. Interdisciplinary teams of neurosurgery and interventional radiology specialists should evaluate and treat such patients by using diagnostic and therapeutic angiography and, if necessary, surgery.
James K. Liu, Kelly Mahaney, Stanley L. Barnwell, Sean O. McMenomey and Johnny B. Delashaw Jr.
The anterior condylar confluence (ACC) is located on the external orifice of the canal of the hypoglossal nerve and provides multiple connections with the dural venous sinuses of the posterior fossa, internal jugular vein, and the vertebral venous plexus. Dural arteriovenous fistulas (DAVFs) of the ACC and hypoglossal canal (anterior condylar vein) are extremely rare. The authors present a case involving an ACC DAVF and hypoglossal canal that mimicked a hypervascular jugular bulb tumor.
This 53-year-old man presented with right hypoglossal nerve palsy. A right pulsatile tinnitus had resolved several months previously. Magnetic resonance imaging demonstrated an enhancing right-sided jugular foramen lesion involving the hypoglossal canal. Cerebral angiography revealed a hypervascular lesion at the jugular bulb, with early venous drainage into the extracranial vertebral venous plexus. This was thought to represent either a glomus jugulare tumor or a DAVF.
The patient underwent preoperative transarterial embolization followed by surgical exploration via a far-lateral transcondylar approach. At surgery, a DAVF was identified draining into the ACC and hypoglossal canal. The fistula was surgically obliterated, and this was confirmed on postoperative angiography. The patient's hypoglossal nerve palsy resolved.
Dural arteriovenous fistulas of the ACC and hypoglossal canal are rare lesions that can present with isolated hypoglossal nerve palsies. They should be included in the differential diagnosis of hypervascular jugular bulb lesions. The authors review the anatomy of the ACC and discuss the literature on DAVFs involving the hypoglossal canal.
Stanley L. Barnwell, Van V. Halbach, Christopher F. Dowd, Randall T. Higashida, Grant B. Hieshima and Charles B. Wilson
✓ 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.
Randall T. Higashida, Van V. Halbach, Christopher Dowd, Stanley L. Barnwell, Bill Dormandy, Julie Bell and Grant B. Hieshima
✓ Interventional neurovascular techniques for treating patients with intracranial aneurysms are now being performed in selected cases. In certain anatomical locations that are difficult to reach surgically, such as the cavernous portion of the internal carotid artery (ICA), this technique may be especially useful. The procedure is performed from a transfemoral approach, using local anesthesia, thus permitting continuous neurological monitoring.
Between 1981 and 1989, 87 patients diagnosed as having an intracavernous aneurysm were treated with endovascular detachable balloon embolization techniques. The patients ranged in age from 11 to 84 years. The presenting symptom was mass effect in 69 cases (79.3%), rupture of a preexisting aneurysm resulting in a carotid-cavernous sinus fistula in eight cases (9.2%), trauma resulting in a cavernous pseudoaneurysm in seven cases (8.0%), and hemorrhage in three cases (3.4%). Therapeutic occlusion of the ICA across or just proximal to the aneurysm neck was performed in 68 patients (78.2%). Since 1984, with the development of a permanent solidifying agent (2-hydroxyethyl methacrylate) to fill the balloon, it is now feasible in some cases to guide the balloon directly into the aneurysm and preserve the parent artery; this was achieved in 19 cases (22%). Follow-up examination has demonstrated complete thrombosis with partial or total alleviation of symptoms in all patients with therapeutic occlusion of the parent vessel. Of the 19 patients with preservation of the parent artery, follow-up studies have demonstrated total exclusion in 12 cases (63%) and subtotal occlusion of greater than 85% in seven cases (37%), with clinical improvement in all cases. Complications from therapy included transient cerebral ischemia during or after therapy requiring volume expansion in seven cases, embolic symptoms requiring antiplatelet medication in two cases, and stroke in four cases; there were no deaths. Detachable balloon embolization therapy, particularly for large and giant symptomatic aneurysms of the cavernous ICA, can be an effective mode of treatment.