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R F Spetzler

Publications and source records attributed to R F Spetzler.

At least 127 records · Page 7Linked to original sources
PubMed1995

Giant serpentine aneurysms: a review and presentation of five cases.

We present five cases of giant serpentine aneurysms (large, partially thrombosed aneurysms containing tortuous vascular channels with a separate entrance and outflow pathway) and review 28 cases reported in the literature. Giant serpentine aneurysms should be considered as a subgroup of giant aneurysms, distinct from saccular and fusiform varieties, given their unique clinical presentation and radiographic features.

Adolescent↗
PubMed1995

Surgical management of giant intracranial aneurysms: experience with 171 patients.

Patients with untreated giant intracranial aneurysms have a dismal prognosis as a result of hemorrhage, cerebral compression, and thromboembolism. Therefore, giant aneurysms should be treated. The operative approach is chosen to maximize exposure of the aneurysm. Direct clipping of the aneurysm neck, with preservation of the parent and branch vessels, is the preferred method of occlusion. Hypothermic circulatory arrest may facilitate clipping in selected patients. Alternative techniques for unclippable aneurysms can be utilized, but they compromise parent arteries and require revascularization to maintain CBF. Because mass effect is an important cause of patient morbidity, giant aneurysms are usually debulked after they have been eliminated completely from the circulation. Giant aneurysms are complex lesions that demand thorough surgical planning, individualized strategies, and a multidisciplinary effort.

Adolescent↗
PubMed1995

Radical resection of anterior skull base tumors.

The transfacial approaches give the surgeon wide exposure for resecting skull base lesions. The classification system, using six levels, helps plan the best surgical strategy. Our experience with the transfacial approaches has been associated with acceptably low rates of morbidity and mortality. Our small experience with carotid sacrifice reflects our practice of preserving the ICA whenever possible. We recommend preserving the ICA with benign tumors because they do not invade the artery, or they invade it to a limited extent. In contrast, we recommend radical tumor resection and sacrifice of the ICA with malignant tumors, because they directly threaten the integrity of the ICA and a patient's survival. The ICA should not be considered a limitation to radical tumor resection, because the ICA can be safely reconstructed with an appropriate bypass procedure.

Adolescent↗
PubMed1994

Repair of vertebral artery injury during anterior cervical decompression.

METHODS: Vertebral artery injury is a rarely described complication of anterior cervical decompression. The authors performed a retrospective review of their operative database for the purposes of defining the optimal management of this complication and its avoidance. RESULTS: Four of 1,215 (0.3%) patients undergoing anterior cervical operation sustained arterial injuries. In three cases, primary repair of the artery was successful; in one case, the artery was exposed and ligated. There were no postoperative ischemic complications. Artery laceration occurred during decompression (n = 2), screw tapping (n = 1), and during soft tissue retraction (n = 1). CONCLUSIONS: Injury to the vertebral artery during anterior approaches can be avoided by preoperative identification of anomalous arteries and by intraoperative attention to the midline. When the artery is injured, primary repair may be the optimal management strategy.

Cervical Vertebrae↗
PubMed1994

Cavernous malformations of the brain stem. A review of 139 cases.

A retrospective analysis of 139 patients with brain stem cavernous malformations is presented. The material consists of 41 cases from Bern and Phoenix and 98 further well-documented cases from the literature. Sixty-eight patients were male, 70 were female. The average age was 31.8 + 11.8 years. Sixty-two percent of the cavernous malformations were in the pons, 14% were in the mesencephalon, 12% were in the pontomesencephalic and in the pontomedullary junction, and 5% were in the medulla. Eighty-eight percent of the patients showed evidence of recent or previous hemorrhage, 55% had one hemorrhage. 17% had two hemorrhages, and 17% had three or more hemorrhages. Twelve patients died from a hemorrhage, 5 with the first bleeding and 7 with a rebleeding. The minimum bleeding rate was 2.7% per year and the average rebleeding rate 21% per year and per lesion. Most lesions had a diameter between 10 and 30 mm. Increase in size was observed in 12 of the patients; this corresponds to about 21% when only patients with a follow-up of at least one year are considered. In 93 patients the cavernous malformation was removed operatively while in 30 patients the lesion was not removed. In the group with conservative management at the end of the observation period (up to 25 and 32 years), 66.6% had no or only a slight neurological deficit, 6.7% were moderately disabled, 6.7% were completely dependent, and 20% had died. In the group treated surgically 83.9% had no or only a slight neurological deficit, and 15% were moderately disabled. One patient remained severely disabled, no patient died. The limitations of the retrospective nature of this study are stressed.

Adolescent↗
PubMed1994

Cardiopulmonary bypass, hypothermic circulatory arrest and barbiturate cerebral protection for the treatment of giant vertebrobasilar aneurysms in children.

Intracranial aneurysms in the pediatric population are rare lesions with a significant proportion occurring as giant aneurysms involving the vertebrobasilar system. The complex anatomy of these lesions frequently creates an extremely difficult management dilemma. We present two patients, a 9-year-old and a 13-year-old, with giant fusiform vertebrobasilar aneurysms, to illustrate the utility of cardiopulmonary bypass, hypothermic circulatory arrest and barbiturate cerebral protection for successful surgical treatment of these complex intracranial vascular lesions in children.

Adolescent↗
PubMed1994

The natural history of familial cavernous malformations: results of an ongoing study.

Cavernous malformations are congenital abnormalities of the cerebral vessels that affect 0.5% to 0.7% of the population. They occur in two forms: a sporadic form characterized by isolated lesions, and a familial form characterized by multiple lesions with an autosomal dominant mode of inheritance. The management of patients with cavernous malformations, particularly those with the familial form of the disease, remains a challenge because little is known regarding the natural history. The authors report the results of an ongoing study in which six families afflicted by familial cavernous malformations have been prospectively followed with serial interviews, physical examinations, and magnetic resonance (MR) imaging at 6- to 12-month intervals. A total of 59 members of these six families were screened for protocol enrollment; 31 (53%) had MR evidence of familial cavernous malformations. Nineteen (61%) of these 31 patients were symptomatic, with seizures in 12 (39%), recurrent headaches in 16 (52%), focal sensory/motor deficits in three (10%), and visual field deficits in two (6%). Twenty-one of these 31 patients underwent at least two serial clinical and MR imaging examinations. A total of 128 individual cavernous malformations (mean 6.5 +/- 3.8 lesions/patient) were identified and followed radiographically. During a mean follow-up period of 2.2 years (range 1 to 5.5 years), serial MR images demonstrated 17 new lesions in six (29%) of the 21 patients; 13 lesions (10%) showed changes in signal characteristics, and five lesions (3.9%) changed significantly in size. The incidence of symptomatic hemorrhage was 1.1% per lesion per year. The results of this study demonstrate that the familial form of cavernous malformations is a dynamic disease; serial MR images revealed changes in the number, size, and imaging characteristics of lesions consistent with acute or resolving hemorrhage. It is believed that the de novo development of new lesions in this disease has not been previously reported. These findings suggest that patients with familial cavernous malformations require careful follow-up monitoring, and that significant changes in neurological symptoms warrant repeat MR imaging. Surgery should be considered only for lesions that produce repetitive or progressive symptoms. Prophylactic resection of asymptomatic lesions does not appear to be indicated.

Adolescent↗
PubMed1994

Hemodynamics of subarachnoid hemorrhage arrest.

Subarachnoid hemorrhage (SAH) causes a spectrum of clinical syndromes from mild discomfort to rapid brain death. The reason for these heterogeneous consequences is poorly understood. A canine autologous shunt model of SAH was used to study this problem. The duration and volume of hemorrhage into the suprasellar cistern at each animal's mean arterial blood pressure were measured at variable hemorrhage flow rates. At high rates of bleeding in seven dogs (18.7 +/- 2.2 ml/min, mean +/- standard deviation), hemorrhage duration was significantly less (191 +/- 116 seconds, p < 0.03) and hemorrhage volume was significantly greater (15.1 +/- 7.0 ml, p < 0.05) than at low flow rates. At low flow rates of bleeding in nine dogs (4.4 +/- 2.2 ml/min), hemorrhage duration was 394 +/- 202 seconds and volume was 10.9 +/- 6.5 ml. Cerebral perfusion pressure (CPP) decreased at all hemorrhage rates but never to 0 mm Hg (perfusion arrest). No correlation between a decrease in CPP and SAH volume or duration was identified. The initial flow rate of SAH had a positive linear correlation with the volume of hemorrhage (23 dogs, r = 0.64, p < 0.01). The data suggest that initial SAH flow rate, and not CPP, has a primary influence on hemorrhage arrest. This finding may influence the clinical rationale for acute management of SAH-induced brain injury.

Animals↗
PubMed1994

The far lateral/combined supra- and infratentorial approach. A human cadaveric prosection model for routes of access to the petroclival region and ventral brain stem.

A far lateral approach to the ventral brain stem, lower clivus, and anterior foramen magnum is described. Methods for further exposure of the superior petroclival region by incorporating a subtemporal craniotomy and posterior petrosectomy are also demonstrated. Eight sequentially illustrated steps depict this technique. The far lateral/combined supra- and infratentorial exposure is a comprehensive surgical approach that provides direct access to the entire anterior and lateral brain stem and craniovertebral junction. It minimizes brain-stem retraction and maximizes visualization of the neurovascular structures.

Adipose Tissue↗
PubMed1994

Giant posterior communicating artery aneurysm presenting as third ventricle mass with obstructive hydrocephalus. Case report.

The case of a giant posterior communicating artery (PCoA) aneurysm is reported in which the initial presentation was coma secondary to obstructive hydrocephalus. The primary radiological diagnosis was a probable craniopharyngioma. A cerebral angiogram revealed a partially thrombosed giant PCoA aneurysm on the right side. The patient underwent pterional craniotomy with aneurysm clipping and thrombectomy to relieve mass effect, and has made a good recovery. Review of the literature documents that giant PCoA aneurysms are rare. This is believed to be the first reported case of a PCoA aneurysm presenting as a third ventricle mass with obstructive hydrocephalus. The magnetic resonance imaging characteristics of those third ventricle masses that mandate vascular workup are discussed.

Basilar Artery↗
PubMed1994

Combined surgical and endovascular treatment of a giant vertebral artery aneurysm in a child. Case report.

The case is presented of a 5-year-old child who suffered a subarachnoid hemorrhage from a giant left vertebral artery-posterior inferior cerebellar artery (PICA) aneurysm. Initial treatment consisted of surgical occlusion of the parent vertebral artery combined with a PICA-to-PICA bypass. Because of persistent filling of the aneurysm, the left PICA was occluded at its takeoff from the aneurysm. Endovascular coil occlusion of the aneurysm and the distal left vertebral artery enabled complete elimination of the aneurysm. Follow-up magnetic resonance imaging and arteriography performed 6 months postoperatively showed persistent occlusion and elimination of the mass effect. Combined surgical bypass and endovascular occlusion of the parent artery may be a useful adjunct in the management of these aneurysms.

Anastomosis, Surgical↗
PubMed1994

Petroclival lesions.

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Cerebellar Neoplasms↗
PubMed1994

Efficacy of endovascular treatment of meningiomas: evaluation with matched samples.

PURPOSE: To evaluate the clinical efficacy, cost-effectiveness, and safety of presurgical devascularization of meningiomas. METHODS: Matched samples of embolized and nonembolized groups of meningiomas were compared. The study variables for clinical efficacy were estimated blood loss, number of transfusions, surgical resection time, and length of hospitalization. The cost-effectiveness was evaluated by adjusting all hospital costs to 1991 dollar amounts, and adding additional embolization costs and fees to the hospital cost totals for the embolized group. A qualitative comparison of complications was made. RESULTS: All dependent variables evaluating the clinical efficacy of the procedure (estimate blood loss, 533 cc versus 836 cc; number of transfusions, 0.39 units versus 1.56 units; surgical resection time, 305.8 minutes versus 337.5 minutes; and length of hospitalization, 10.6 days versus 15.0 days) displayed trends of higher means in the nonembolized group; however, only the estimated blood loss and number of transfusions variables were significant. The cost-effectiveness of the procedure was not statistically significant. The mean cost was $29,605 for the embolized group and $38,449 for the nonembolized group. There were three major and nine minor complications in the nonembolized group and zero major and six minor complications in the embolized group. There were four additional minor complications caused by the embolization procedure. CONCLUSION: Endovascular devascularization of meningiomas is beneficial for large meningiomas because it diminishes the necessity of intraoperative transfusions and decreases blood loss. The additional day of hospitalization, emolization costs, and costs of complications do not conversely increase treatment costs. There were no major complications or adverse long-term effects caused by the embolization procedure.

Blood Loss, Surgical↗
PubMed1994

Materials and embolic agents for endovascular treatment.

The refinement in the intravascular techniques has revolved upon the development of new material and a better understanding of neurophysiology. Access has become less of a limitation, and more emphasis is now placed on getting the job done: closing a fistula, obliterating a malformation, or filling an aneurysm. Embolic materials available have greatly changed according to the indication at hand. The focus now is on the specific uses for the agent instead of toxicity or dose-response trials.

Chemoembolization, Therapeutic↗
PubMed1994

The prospective application of a grading system for arteriovenous malformations.

The decision-making process whereby treatment is offered to a patient with an arteriovenous malformation (AVM) must be supported by an understanding of the risks related to the natural history of the AVM and the risks related to the treatment of that particular AVM. The ability to estimate the treatment risk for an individual patient is hampered by the marked variability in the complexity of AVMs. In 1986, an AVM grading system was proposed to predict surgical morbidity and mortality. This system is based on the AVM size, the neurological eloquence of adjacent brain, and the pattern of venous drainage. Grade I malformations are small, superficial, and located in noneloquent cortex; Grade V lesions are large, deep, and situated in neurologically critical areas; and Grade VI lesions are considered inoperable AVMs. A retrospective application of this grading scheme demonstrated its correlation with the incidence of postoperative neurological complications. A prospective application of the AVM grading system has been performed in 120 consecutive patients who had a complete microsurgical excision of their AVM, with or without AVM embolization. The AVM grading system accurately correlated with both new-temporary (P < 0.0001) and new-permanent (P = 0.008) neurological deficits. The permanent major neurological morbidity rates for Grades I through III were 0%, increasing to 21.9% in patients with Grade IV and 16.7% in patients with Grade V AVMs (P < 0.0001). One patient with a Grade III AVM died from an esophageal hemorrhage 15 months after her AVM was treated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗