Biomedical subjects

Robert F Spetzler

Publications and source records attributed to Robert F Spetzler.

At least 55 records · Page 3Linked to original sources

PubMed2005

Bilateral ethmoidal dural arteriovenous fistulae: a previously unreported entity: case report.

OBJECTIVE AND IMPORTANCE: Ethmoidal dural arteriovenous fistulas (AVFs) are rare intracranial lesions associated with a high risk of intracranial hemorrhage. Reported hemorrhage rates have ranged from 62 to 91%, and an aggressive clinical course is more likely than a benign clinical course. We describe the first case of a patient with bilateral ethmoidal dural AVFs. CLINICAL PRESENTATION: A 50-year-old man presented with posterior fossa subarachnoid hemorrhage and cerebellar intraparenchymal hemorrhage. Angiography revealed a tentorial AVF and a complex anterior ethmoidal dural AVF. INTERVENTION: The tentorial AVF was treated with preoperative embolization and surgical obliteration. On follow-up angiography, the ethmoidal dural AVF was not considered amenable to embolization. A right modified orbitozygomatic approach was performed and the right-sided fistula was interrupted. Intraoperative angiography revealed obliteration of the right-sided fistula, but a persistent fistula on the left. Further surgical exploration revealed this contralateral anterior ethmoidal dural AVF, which was clip ligated. No residual fistula was noted on intraoperative angiography. CONCLUSION: Anterior ethmoidal dural AVFs may occur bilaterally. Given their complex angiographic appearance, their presence bilaterally may not be readily apparent on preoperative angiography. Intraoperative angiography is crucial to identify a contralateral fistula and to verify that ligation has been curative.

Carotid Artery, Internal↗

PubMed2005

Sinonasal leiomyosarcoma: review of literature and case report.

OBJECTIVES/HYPOTHESIS: To determine prognosis of primary sinonasal leiomyosarcomas after treatment. STUDY DESIGN: Literature review and case report. METHODS: Review of English literature from MEDLINE and independent sources with the addition of our case. RESULTS: Including our case, 63 cases have been reported. Primary treatment includes resection with or without radiation. Chemotherapy has not been reported to be effective. In our case, however, chemotherapy, consisting of etoposide and high-dose ifosfamide, caused the tumor to shrink significantly. On the basis of a review of all reported cases, the overall survival rate at a mean follow-up of 38.24 month is 66%. The minimal overall survival rates at 5 and 10 years are 20% and 6%, respectively. CONCLUSION: The prognosis for primary sinonasal leiomyosarcomas is poor. However, a 10-year survival has been reported in a few patients. Chemotherapy may be a useful adjunct when managing extensive lesions unamenable to curative resection.

Adult↗

PubMed2005

Exposure of midline cranial base without a facial incision through a combined craniofacial-transfacial procedure.

OBJECTIVE: A single-stage combined craniofacial-transfacial approach that exposes the midline cranial base without visible facial incisions is described. METHODS: Between 1992 and 1998, eight patients underwent surgery for five different anterior cranial base pathological findings: four angiofibromas, one mesenchymal chondrosarcoma, one esthesioneuroblastoma, one odontogenic myxoma, and one encephalocele. In all cases, the surgical exposure consisted of a bicoronal scalp incision with a bifrontal craniotomy and fronto-orbitonasal osteotomy, and then a sublabial incision for transmaxillary exposure. RESULTS: Gross total resection was achieved in five cases. The encephalocele was resected with complete reconstruction of the bony defect. Seven patients developed complications, primarily wound infections, cerebrospinal fluid leaks, and anemia. Postoperative Karnofsky Performance Scale scores ranged between 80 and 100 (mean, 92.5). Long-term follow-up information (mean, 56 mo; median, 59.5 mo; range, 5-108 mo) was available for all patients. CONCLUSION: Large anterior cranial base lesions can be resected and excellent cosmetic outcomes can be achieved with a single-stage combined transfacial-craniofacial approach that exposes the entire midline cranial base and requires no facial incisions.

Adolescent↗

PubMed2005

Orbitozygomatic approach to basilar apex aneurysms.

Basilar apex region aneurysms are among the most complex cerebral aneurysms. They are not, however, among the most common aneurysms, and increased use of endovascular treatment has further decreased the number of patients with these lesions who undergo surgery. Nonetheless, not all basilar apex aneurysms are amenable to coil embolization, and neurosurgeons must be prepared to treat patients with basilar apex aneurysms surgically. We prefer an orbitozygomatic craniotomy and transsylvian approach. Meticulous exercise of the basic tenets of aneurysm surgery (proximal vascular control, sharp dissection, and preservation of perforating vessels) is crucial to optimal patient outcomes.

Craniotomy↗

PubMed2005

Use of "bonnet" bypass with radial artery interposition graft in a patient with recurrent cranial base carcinoma: technical report of two cases and review of the literature.

OBJECTIVE AND IMPORTANCE: Two patients with recurrent cranial base carcinomas involving the carotid artery received a "bonnet" bypass using the contralateral superficial temporal artery as the donor vessel because the ipsilateral common and external carotid arteries were unavailable. The radial artery was used as the graft. CLINICAL PRESENTATION: A 58-year-old man with ear pain and an enlarging mass involving the left cranial base and neck had undergone a right partial glossectomy and modified neck dissection followed by radiotherapy for squamous cell carcinoma. Recurrent carcinoma extensively involved the left internal carotid artery. A 46-year-old man with jaw pain and hoarseness had undergone multiple resections and radiation therapy for medullary thyroid carcinoma. Magnetic resonance imaging showed recurrent tumor on the right. INTERVENTION: Both patients underwent a pterional craniotomy. The supraclinoid internal carotid artery was exposed. The radial artery was harvested. The contralateral superficial temporal artery was dissected at its bifurcation into the frontal and parietal branches. The radial artery graft was anastomosed to the superficial temporal artery and a recipient ipsilateral branch of the middle cerebral artery. The internal carotid artery was clip-ligated. After surgery, both patients remained neurologically stable. Angiography confirmed that the bypasses were patent and that the middle cerebral artery territory filled. The patients' carcinomas were resected aggressively. CONCLUSION: When aggressive resection of cranial base tumors is needed and the ipsilateral carotid artery is unavailable as a donor vessel, a "bonnet" bypass with carotid artery sacrifice may be performed. Compared with vein grafts, microsurgical anastomosis is easier and the patency rate is higher with a radial artery graft.

Cerebral Revascularization↗

PubMed2005

Intra-arterial thrombolysis for acute ischemic stroke: preliminary experience with platelet glycoprotein IIb/IIIa inhibitors as adjunctive therapy.

OBJECTIVE: To evaluate the safety profile of platelet glycoprotein IIb/IIIa inhibitors administered as adjunctive therapy to patients with large-vessel occlusion and acute ischemic stroke refractory to pharmacological thrombolysis with recombinant tissue plasminogen activator (rtPA) and mechanical disruption, balloon angioplasty, or both. METHODS: Twenty-one patients (mean age, 62 yr; range, 29-88 yr) met the following criteria: 1) large-vessel occlusion and acute ischemic stroke syndrome at presentation, 2) failure to recanalize after administration of rtPA (intra-arterial and/or intravenous) with or without mechanical thrombolysis, and 3) subsequent treatment with IIb/IIIa inhibitors (intra-arterial or intravenous). RESULTS: Eleven patients had ischemia in the dominant hemisphere, 8 in the vertebrobasilar system, and 2 in the nondominant hemisphere. Twelve patients received intravenous rtPA without significant improvement; 9 patients were not candidates for intravenous rtPA. All patients received intra-arterial rtPA. The IIb/IIIa inhibitors were administered intravenously in 3 patients, intra-arterially in 16, and both intravenously and intra-arterially in 2. Balloon angioplasty was performed in 18 patients. Complete or partial recanalization was achieved in 17 of the 21 patients. After thrombolysis, 15 improved clinically. Three patients (14%) sustained an asymptomatic intracerebral hemorrhage after thrombolytic therapy. No patient was clinically worse after intervention. At last follow-up (mean, 8.5 mo), 13 patients were functionally independent (modified Rankin score, 0-3) and 8 were disabled or dead. CONCLUSION: IIb/IIIa inhibitors are an alternative for achieving recanalization. The risk of hemorrhage may be low. As part of an escalating protocol that includes pharmacological and mechanical thrombolysis, IIb/IIIa inhibitors may improve clinical outcomes.

Abciximab↗

PubMed2005

Quantitative anatomic study of three surgical approaches to the anterior communicating artery complex.

OBJECTIVE: To compare the angles of approach and area of exposure to the anterior communicating artery (AComA) complex associated with pterional (PT), orbitopterional (OPT), and orbitozygomatic (OZ) craniotomies before and after gyrus rectus resection. METHODS: PT, OPT, and OZ craniotomies were performed on both sides of four heads, and the angles of approach and area of exposure to the AComA complex were measured before and after resection of the gyrus rectus. RESULTS: The vertical angle of approach increased significantly among the PT and OPT (P = 0.001), PT and OZ (P = 0.001), and OPT and OZ approaches (P = 0.005). The horizontal angle of approach was significantly larger between the PT to OPT (P = 0.001) and PT to OZ (P = 0.001) approaches but not between the OPT and OZ approaches (P = 0.757). After gyrus rectus resection, the vertical and horizontal angles of approach increased significantly for the PT approach but not for the OPT and OZ approaches. The area of exposure to the AComA complex increased progressively from the PT to OPT to OZ approach but did not reach statistical significance (P = 0.124). Resection of the gyrus rectus resulted in significant relative gains in the area of exposure for the PT (P = 0.01) and OPT (P = 0.04) approaches but not for the OZ approach (P = 0.88). CONCLUSION: The vertical and horizontal angles of approach to the AComA complex are significantly larger for the OPT and OZ approaches compared with the PT approach. Use of the OZ approach may decrease the need for frontal lobe retraction and resection of the gyrus rectus.

Anterior Cerebral Artery↗

PubMed2005

Microsurgical anatomy of the transcallosal anterior interforniceal approach to the third ventricle.

OBJECTIVE: We explored relevant regional microanatomy as it relates to the challenging anterior interforniceal (AIF) approach for removing hypothalamic hamartomas. METHODS: Five silicone-injected cadaveric heads were dissected by use of frameless stereotactic navigation to reveal microanatomy and extent of exposure through the transcallosal AIF approach. Distances between trajectories to the coronal suture and the genu of the corpus callosum (CC) and between the posterior border of the anterior commissure to the lower end of the rostrum of the CC and posterior border of the foramen of Monro were measured. RESULTS: The AIF approach provided adequate access to the anterior third ventricle and related structures (i.e., hypothalamus, infundibular recess, and mamillary bodies) through the corridor bounded by the anterior commissure anteriorly and the choroid plexus at the foramen of Monro posteriorly. The mean distances from the posterior trajectory to the coronal suture and the genu of the CC were 44.8 mm (range, 43.8-46.2 mm) and 14.88 mm (14.1-15.7 mm), respectively. The mean distance from the anterior trajectory posterior to the coronal suture was 4.66 mm (0-8.9 mm), and 32.6 mm (30.5-33.9 mm) to the genu of the CC. The mean length of callosotomy was 17.52 mm (16.2-19.1 mm). The mean distance between the posterior border of the anterior commissure and the lower end of the rostrum of the CC was 5.22 mm (4.6-5.6 mm), and 10.52 mm (9.7-11.5 mm) to the posterior border of the foramen of Monro. CONCLUSION: The technically safe AIF approach permitted limited interforniceal splitting, no major deep vein manipulation, and adequate visualization of the hypothalamus, infundibular recess, and mamillary bodies.

Cadaver↗

PubMed2005

Preserving olfactory function in anterior craniofacial surgery through cribriform plate osteotomy applied in selected patients.

OBJECTIVE: Olfaction is often sacrificed to gain access to the cranial base in anterior craniofacial surgery. We describe the long-term results of olfactory function in patients who underwent anterior craniofacial surgery and a cribriform plate osteotomy to preserve olfaction. METHODS: Between 1992 and 2004, 28 patients underwent 29 cribriform plate osteotomies in an attempt to preserve olfaction during anterior craniofacial surgery performed through modified extended transbasal approaches. Patients' charts and office notes were reviewed retrospectively. Formal olfactory testing was available in 5 patients, but most data were based on patients' subjective reports of olfaction. Olfactory preservation was defined by the subjective ability to detect fumes such as coffee, chocolate, roses, and orange juice regardless of the intensity of the sensation. Follow-up was based on phone calls to patients. RESULTS: Four patients were lost to follow-up and excluded. Therefore, follow-up was available in 24 patients after 25 procedures. On the basis of patients' subjective reports, olfaction was spared in 22 patients after 23 procedures (92%) and was confirmed objectively in the five patients formally tested. After surgery, only two patients were anosmic. CONCLUSION: Olfaction can be preserved in selected patients undergoing anterior craniofacial surgery. At least 1 cm of nasal mucosa should remain attached to the cribriform plate, which can be achieved by including the nasal bone in the osteotomy of the orbital bar. A medial orbital canthopexy is therefore necessary after these procedures.

Adolescent↗

PubMed2005

Supratentorial arteriovenous malformations.

Arteriovenous malformations are a heterogeneous group of intra-axial central nervous system vascular lesions consisting of tangles of abnormal arteriovenous connections without intervening capillary beds. The heterogeneity of arteriovenous malformations is described by the Spetzler-Martin grading scale, a scale that also forms the basis for clinical decision making. The microsurgical treatment of appropriately selected supratentorial arteriovenous malformations is based on the tenets of circumferential isolation and transection of arterial feeders, preservation of vessels en passant and surrounding functional neural tissue, and skeletonization and transection of venous drainage.

Brain↗

PubMed2005

Microsurgical anatomy and quantitative analysis of the transtemporal-transchoroidal fissure approach to the ambient cistern.

OBJECTIVE: Surgical approaches to ambient cistern lesions are complex. We investigated the microanatomy of the transtemporal-transchoroidal fissure approach to the ambient cistern with emphasis on exposure of the posterior cerebral artery. METHODS: Dissections were performed bilaterally in five silicone-injected cadaveric heads. Critical anatomic distances, specifically with reference to the P2 segment of posterior cerebral artery in relation to the inferior choroidal point and P2-P3 junction, were measured with digital calipers. Other landmarks (temporal lobe tip, points from the temporal base to the choroidal fissure) were included for quantitative analysis. RESULTS: The transtemporal-transchoroidal fissure approach provided adequate exposure of the ambient cistern, minimized temporal lobe retraction, and allowed assessment of regional microanatomy. The mean distance from the temporal base to the choroidal fissure measured 18.09 mm (range, 16.9-21.9 mm). The distances from the choroidal fissure to P2 varied at the coronal plane of the inferior choroidal point (mean, 6.96 mm; range, 3.6-12.0 mm) and the P2-P3 junction (mean, 6.02 mm; range, 4.3-6.9 mm), respectively. CONCLUSION: The transtemporal-transchoroidal fissure approach provides a corridor to the ambient cistern and P2-P3 junction while minimizing temporal lobe retraction and avoiding interruption of temporal lobe venous drainage. Because of widely variable vascular anatomy, access to posterior cerebral artery lesions using this approach requires preoperative imaging to identify the specific location of the P2-P3 junction.

Arachnoid↗

PubMed2005

Far-lateral approach to the craniocervical junction.

The far-lateral approach is an extension of the standard suboccipital approach, designed to maximize exposure of the lateroventral craniocervical junction. Following a basic principle of cranial base surgery, the angle of view is increased by bone removal. Bone removal involves the most lateral part of the inferior occipital squama and the posterior arch of C1. Drilling of various portions of the occipital condyle further increases the exposure. Transposition of the vertebral artery is seldom required. The far-lateral approach allows a tangential, unobstructed view of the lateroventral cervicomedullary area and can be applied effectively to manage with a heterogeneous spectrum of pathological lesions involving this area. The technical aspects of the procedure are briefly illustrated in this report.

Atlanto-Axial Joint↗

PubMed2005

Spontaneous spinal subarachnoid hemorrhage secondary to spinal aneurysms: diagnosis and treatment paradigm.

INTRODUCTION: Isolated spinal aneurysms are rare; only a few have been reported. To the best of our knowledge, this series represents the largest experience with four ruptured spinal aneurysms, all of which were treated surgically. METHODS: Clinical information from the hospital charts and diagnostic images of four patients with the diagnosis of spinal aneurysms were reviewed from the senior authors' (RFS, JMZ) office database, surgical reports, and radiological imaging database. Follow-up examinations were performed by phone interview, when possible, and by chart review. RESULTS: Between 1997 and 2004, four patients with ruptured spinal aneurysms underwent surgical treatment. All aneurysms were located within the spinal canal and manifested with spinal subarachnoid hemorrhage. No collagen disease, aortic coartaction, arteriovenous fistula, or arteriovenous malformations were identified in these patients. CONCLUSION: Subarachnoid hemorrhage within the spinal cord can be caused by ruptured aneurysms. Spinal aneurysms are rare, but should be considered within the differential diagnosis of patients with intracranial subarachnoid hemorrhage when cranial angiography is negative. Magnetic resonance imaging and selective spinal angiography are useful for workup, but definitive diagnosis may require surgical exploration.

Adult↗

PubMed2005

De novo presentation of an arteriovenous malformation. Case report and review of the literature.

The authors report the case of a patient with a de novo arteriovenous malformation (AVM), indicating that the origin of these lesions may not always be congenital. A 3-year-old girl who was struck by a car suffered a mild head injury and experienced posttraumatic epilepsy. The initial magnetic resonance (MR) image obtained in this child revealed only a small contusion in the left frontal lobe. Intractable epilepsy subsequently developed. A second MR image obtained almost 4 years after the injury demonstrated an AVM in the right posterior temporal lobe that was verified using angiography. The lesion was classified as a Spetzler-Martin Grade III AVM. The patient underwent embolization of the feeding vessels followed by gamma knife surgery. Fourteen months after treatment she was asymptomatic. Follow-up MR images demonstrate no evidence of an AVM and no changes in the white matter. This case presents a de novo AVM that developed within approximately 4 years. The findings indicate that AVMs may not always be congenital and reinforce the concept that the natural history of AVMs is dynamic. Lesions may appear de novo, grow, and thrombose spontaneously.

Accidents, Traffic↗

PubMed2005

The radical transbasal approach for resection of anterior and midline skull base lesions.

OBJECT: Craniofacial surgery can be performed to treat midline and anterior skull base lesions by creating a bicoronal scalp incision without the need for an additional transfacial procedure. Originally described as the transbasal approach, several modifications for further exposure of the skull base have been described. The authors present data on the application and outcomes of a modified transbasal approach. The radical transbasal approach consists of a bifrontal craniotomy and a frontoorbitonasal osteotomy. METHODS: Between 1992 and 2002, 41 patients (28 male and 13 female patients with a mean age of 38.3 years [range 7-77 years]) underwent 44 radical transbasal procedures. Twenty-three malignant and 18 benign lesions involving the midline skull base were treated. These cases were reviewed retrospectively. Gross-total resection of 30 lesions was achieved. Seven lesions were resected subtotally and six partially; one lesion was debulked. Complications occurred in 26 (59.1%) of the 44 operations and mostly consisted of cerebrospinal fluid leakage. The surgery-related mortality rate was 6.8% (three patients). Based on their pre- and postoperative Karnofsky Performance Scale scores, 86.4% of patients improved or remained the same. CONCLUSIONS: The radical transbasal approach increases the midline craniofacial corridor by allowing the globes to be safely retracted laterally. It also enhances exposure of the maxillary sinus from above. The morbidity and mortality rates associated with this procedure are high but consistent with the known rates for craniofacial surgery. This approach is best suited for the treatment of anterior skull base tumors that extend into the nasal cavity, orbit, ethmoid sinus, nasopharynx, and upper clivus. The approach may allow resection of tumors involving the maxillary sinus area without the need for an additional transfacial approach.

Adolescent↗

PubMed2005

Prospective evaluation of surgical microscope-integrated intraoperative near-infrared indocyanine green videoangiography during aneurysm surgery.

OBJECT: The authors prospectively compared a new technique of surgical microscope-based indocyanine green (ICG) videoangiography with intraoperative or postoperative digital subtraction (DS) angiography. METHOD: The technique was performed during 187 surgical procedures in which 124 aneurysms in 114 patients were clipped. Using a newly developed setup, the ICG technique has been integrated into an operating microscope (Carl Zeiss Co., Oberkochen, Germany). A microscope-integrated light source containing infrared excitation light illuminates the operating field. The dye is injected intravenously into the patient, and intravascular fluorescence from within the blood vessels is imaged using a video camera attached to the microscope. The patency of parent, branching, and perforating arteries and documentation of clip occlusion of the aneurysm as shown by ICG videoangiography were compared with intraoperative or postoperative findings on DS angiography. The results of ICG videoangiography corresponded with intra- or postoperative DS angiography in 90% of cases. The ICG technique missed mild but hemodynamically irrelevant stenosis that was evident on DS angiography in 7.3% of cases. The ICG technique missed angiographically relevant findings in three cases (one hemodynamically relevant stenosis and two residual aneurysm necks [2.7% of cases]). In two cases the missed findings were clinically and surgically inconsequential; in the third case, a 4-mm residual neck may require a second procedure. Indocyanine green videoangiography provided significant information for the surgeon in 9% of cases, most of which led to clip correction. CONCLUSIONS: Microscope-based ICG videoangiography is simple and provides real-time information about the patency of vessels of all sizes and about the aneurysm sac. This technique may be useful during routine aneurysm surgery as an independent form of angiography or as an adjunct to intra- or postoperative DS angiography.

Adult↗

PubMed2005

Surgical strategies for approaching hypothalamic hamartomas causing gelastic seizures in the pediatric population: transventricular compared with skull base approaches.

OBJECT: The authors provide evidence that direct resection of hypothalamic hamartomas (HHs) can improve associated gelastic and nongelastic seizures. METHODS: Ten children younger than 17 years of age underwent resection of HHs (nine sessile and one pedunculated) that were causing refractory epilepsy. Lesions were approached from above transventricularly through a transcallosal anterior interforniceal approach in six cases, endoscopically through the foramen of Monro in one, and from below with a frontotemporal craniotomy including an orbitozygomatic osteotomy in three. Medical charts were reviewed retrospectively, and follow-up data were obtained through office records and phone calls. Follow-up periods ranged between 12 and 84 months (mean 16.8 months). All patients in whom the approach was from above had sessile HHs. Five were free from seizures at follow up and two had a reduction in seizures of at least 95%. The transventricular route allowed excellent exposure and visualization of the local structures during resection. Among the three patients in whom the approach was from below, one became free of seizure after two procedures and one had a 75% reduction in epilepsy; the latter two had sessile HHs. The exposure was inadequate, and critical tissue borders were not readily apparent. Although the HH was adequately exposed and resected, the epilepsy persisted in the third patient, who had a pedunculated lesion. The overall rate of major permanent hypothalamic complications appeared to be slightly lower for the orbitozygomatic osteotomy group. CONCLUSIONS: Sessile lesions are best approached from above. Approaches from below adequately expose pedunculated hamartomas. The likelihood of curing seizures seems to be higher when lesions are approached from above rather than from below.

Cerebral Ventricles↗

PubMed2005

Management of arteriovenous malformations: a surgical perspective.

The management strategies for arteriovenous malformations (AVMs) continue to evolve, spurred by advancing technology and improved understanding of the natural history of these lesions. In general, intervention is reserved for Spetzler-Martin Grade I-III lesions or for those with certain high-risk features. Grade IV-V AVMs, in contrast, are usually managed conservatively. Although multimodality therapy incorporating endovascular and/or radiosurgical techniques is increasingly common, microsurgical removal remains the definitive form of treatment.

Arteriovenous Malformations↗