Outcome analysis of preoperative embolization in cranial base surgery.

OBJECTIVE: Management of cranial base tumors requires an interdisciplinary approach. Supraselective angiography and embolization is an important adjunct to cranial base surgery. Though successful embolization facilitates resection, the morbidity of this procedure remains poorly defined. Therefore, we set out to define the morbidity associated with embolization of skull base meningiomas, thus allowing for informed decision making when considering this adjunct to tumor resection. METHODS: A retrospective analysis was performed on our experience with embolization of 167 cranial base meningiomas. Cranial base meningiomas were defined as tumors originating from the olfactory groove, tuberculum sella, medial sphenoid wing, petro-clival region or foramen magnum. RESULTS: 280 feeding vessels were embolized with an average of 1.7 vessels per lesion. In 91% of patients embolized, good to excellent embolization was achieved without permanent neurological sequelae. In 20 patients no embolization was attempted due to the risk of new neurologic deficits or lack of an appropriate vessel for embolization. Twenty-one patients (12.6%) had transient worsening of their neurologic exam or a medical complication requiring hospitalization. Fifteen patients (9%) experienced permanent neurologic deficits or medical morbidity as a result of embolization. Four of the patients who experienced major complications had a decline in previously compromised cranial nerve function. CONCLUSIONS: Embolization of cranial base tumors is an important part of the therapeutic armamentarium for the treatment of cranial base lesions. Recognition of the morbidity of this procedure will allow for the most appropriate use of this powerful adjunct to cranial base surgery.

High-dose intra-arterial cisplatin therapy followed by radiation therapy for advanced squamous cell carcinoma of the head and neck.

OBJECTIVE: To assess the effectiveness of a protocol consisting of 4 cycles of high-dose intra-arterial cisplatin infusions followed by radiation therapy for improving chemotherapy response rates, organ preservation, and survival in patients with advanced-stage untreated and previously treated squamous cell carcinoma of the head and neck. DESIGN AND SETTING: A prospective study of sequentially enrolled patients treated in an academic medical center. The Kaplan-Meier method was used for survival analysis. PATIENTS: Fifty-eight nonpregnant adults, 18 years of age or older, with measurable untreated or recurrent advanced biopsy-proven squamous cell carcinoma of the head and neck. MAIN OUTCOME MEASURES: Response rate to targeted intra-arterial cisplatin infusions, organ preservation, and survival. RESULTS: Fifty-eight patients (44 men and 14 women) were followed up for at least 2 years (median duration of follow-up, 27 months). Twenty-nine (67%) of the 43 previously untreated patients had a complete response to intra-arterial cisplatin therapy. Of the untreated patients, 28 are alive and disease free after a median follow-up time of 30 months. Five of the patients with recurrent disease had a complete response to intra-arterial cisplatin therapy. There were 4 survivors after a median follow-up time of 17.5 months. Of note, there were no deaths or serious complications related to the treatment in either group. CONCLUSIONS: High-dose intra-arterial cisplatin therapy provides a high complete and partial response rate (91%). The combination of high-dose intra-arterial cisplatin and radiation therapy is effective in improving survival and organ preservation rates in patients with previously untreated, advanced squamous cell carcinoma of the head and neck. This treatment protocol is much less effective for recurrent disease.

Vertebral artery to common carotid artery bypass in Takayasu's disease with delayed cerebral ischemia.

UNLABELLED: Takayasu's Arteritis is a progressive occlusive disease of the aortic arch and its branches. It may need several bypass procedures along with or without endovascular techniques. CASE DESCRIPTIONS: A twenty-six year old woman who had a history of Takayasu's Arteritis, and had a Gore-Tex Dacron Y-graft from the ascending aorta to the right subclavian and right common carotid arteries 18 years before, is presented. She presented with recurrent hemispheric ischemia and transient ischemic attacks and severe long segment stenosis in the left common carotid artery. She was successfully treated with a saphenous vein graft bypass from the left vertebral artery to the common carotid artery. The stenosis of the brachiocephalic graft was successfully treated by angioplasty. Three months follow up showed stenosis of the left VA immediately proximal to the proximal anastomosis which was managed successfully with angioplasty. CONCLUSIONS: The surgical treatment of Takayasu's Arteritis with bypass procedures needs a complex overview and follow up. A regular follow up is mandatory for evaluation and planning of appropriate management, in view of the progressive nature of the disease process.

Vasospasm after cranial base tumor resection: pathogenesis, diagnosis, and therapy.

OBJECTIVE: Cerebral vasospasm is well known to occur after various cerebral neurosurgical events that cause subarachnoid hemorrhage. However, cerebral vasospasm can occur after cranial base tumor resection. We present a series of nine patients with angiographically evident vasospasm that was clinically symptomatic in eight of them. METHODS: A total of 470 consecutive patients with cranial base tumors were operated in our institution between April 1993 and December 1996. Nine had evidence of cerebral vasospasm postoperatively (1.9% of the total population), of whom eight were asymptomatic. There were seven males and two females with an age range of 33 to 65 years (average 48.5 years). There were seven meningiomas, one chordoma, and one trigeminal schwannoma. RESULTS: Vasospasm manifested clinically 1 to 30 days postoperatively in eight patients. Most patients were symptomatic within 7 days. In the ninth case, surgery was delayed when asymptomatic vasospasm was noted on an angiogram before second stage surgery. Symptoms included altered mental status in four patients, hemiparesis in three patients (one patient had both hemiparesis and altered mental status), and monoparesis in two patients. Factors that were found to correlate with a higher incidence of vasospasm were tumor size, total operative time, vessel encasement, vessel narrowing, and preoperative embolization. All eight patients with symptomatic vasospasm were treated with hypertensive, hypervolemic, hemodilutional (HHH) therapy. Five patients also underwent intraluminal angioplasty, in conjunction with papaverine in one case. One patient received intraarterial papaverine alone. Angiographic results were good in all patients. Significant clinical improvement was seen in six of the eight symptomatic cases. CONCLUSION: Delayed neurological deterioration in a patient who has undergone cranial base tumor surgery not explained by an intracranial mass lesion should be promptly investigated with angiography. If vasospasm is diagnosed, it should be treated aggressively with hypertensive, hypervolemic, hemodilutional therapy and early angioplasty.

Extradural origin of the posteroinferior cerebellar artery: an anatomic study with histological and radiographic correlation.

OBJECTIVE: The posteroinferior cerebellar artery (PICA) usually arises from the intradural segment of the vertebral artery (VA). The extradural origin of the PICA is infrequent. Its preoperatory identification is important in surgical strategy during the exposure of the VA. METHODS: During an anatomic prosection, the VA was exposed at the craniocervical junction in cadaveric adult specimens. The extradural origin of the PICA was encountered bilaterally in one specimen and on one side in a second specimen. An anatomic study with histological and radiographic correlation was performed. RESULTS: Perforating branches originate from the PICA. They supply the middle and inferior third of the olive and the lateral aspect of the medulla. The PICA has cortical branches that lead to the cerebellum. Injury to the PICA can produce an infarction of these neural structures that can be asymptomatic or cause major neurological deficits. Radiographic results obtained using a lateral projection provided the most reliable delineation of the extradural origin of the PICA. When this artery originates at, or posterior to, the posterior aspect of the occipital condyle, an extradural origin is likely. CONCLUSION: Bilateral selective vertebral angiography should be performed with special attention to the relationships of PICA origins before any surgical exposure of the VA at the craniocervical junction, unless magnetic resonance angiography provides this information without question. A thorough understanding of the relative dominance of the VAs and PICAs, the location of the PICA origin, and the collateral circulation of the posterior fossa are prerequisites to surgery in this region. The preoperative identification of an extradural PICA is important in planning surgical strategy and in avoiding complications during operations near the foramen magnum.

The efficacy and safety of angioplasty for cerebral vasospasm after subarachnoid hemorrhage.

OBJECTIVE: Cerebral angioplasty is being increasingly used for symptomatic vasospasm secondary to subarachnoid hemorrhage. We attempted to determine the safety and efficacy of angioplasty for refractory vasospasm. We also looked at the influence of timing of angioplasty on outcome. METHODS: We retrospectively studied patients with subarachnoid hemorrhage who underwent angioplasty in our institution to determine the safety and the success rate achieved with this procedure. The study period extended from August 1993 until February 1997. Clinical and radiological data were collected, with emphasis on clinical improvement after angioplasty and its relationship with timing of intervention. Thirty-one patients with 43 aneurysms and one case of arteriovenous malformations were included. Their ages varied between 28 and 68 years, with an average age of 44 years. Five patients were assigned Hunt and Hess Grade IV, 15 were assigned Grade III, 7 were assigned Grade II, and 4 were assigned Grade I. All patients except two underwent angioplasty after aneurysm clipping or coiling. RESULTS: Angioplasty was performed an average of 6.9 days after the occurrence of subarachnoid hemorrhage, with a range from 1 to 14 days. It was performed early (within 24 h) after refractory clinical deterioration in 21 patients. A total of 81 vessels were dilated. Three angioplasty-related complications occurred: two femoral hematomas and one retroperitoneal hematoma. Clinical improvement was dramatic after 12 procedures, moderate after 11 procedures, and minimal or nonexistent after 9 procedures. There was a clear tendency toward more significant improvement in patients with earlier angioplasty (<24 h from onset of neurological deficit) (P=0.0038). At discharge, 8 patients had achieved good recoveries (Glasgow Outcome Scale score of 1), 11 had moderate disabilities (Glasgow Outcome Scale score of 2), and 10 had severe disabilities (Glasgow Outcome Scale score of 3). Two deaths were encountered, and they were unrelated to angioplasty. Follow-up was obtained for 27 patients: 25 had good outcomes, 1 was moderately disabled, and 1 died. There was no significant correlation between interval and outcome. CONCLUSION: Our results indicate that angioplasty is a safe and effective treatment for symptomatic vasospasm that is refractory to hyperdynamic hypervolemic therapy. When used early (<24 h), it leads to significant clinical improvement. However, the long-term outcome is good, even in cases of delayed angioplasty. The prevention of worsening of the cerebral ischemia and its extension to other territories may be the reason.

Nonhemorrhagic pituitary macroadenoma producing reversible internal carotid artery occlusion: case report.

Obstruction of the internal carotid artery by a pituitary tumor is a rare occurrence, particularly in the absence of pituitary apoplexy. A cas of occlusion of the right internal carotid artery caused by a nonhemorrhagic pituitary adenoma is reported. The patient presented with a 3-month history of headaches and a progressive loss of vision in his right eye, leading to sudden complete right-sided blindness on the day of admission. Except for the visual system, the patient's clinical examination revealed nothing remarkable. There was complete restoration of blood flow in the internal carotid artery after emergency transsphenoidal resection of the tumor was performed. The patient's vision also substantially improved shortly after the surgery. Neurodiagnostic correlation, using various imaging studies, is presented. This cas also demonstrates the importance of using magnetic resonance imaging with and without contrast to demonstrate complete occlusion or thrombosis in the affected vessel.

Surgical treatment of meningiomas involving the cavernous sinus: evolving ideas based on a ten year experience.

The outcomes of 114 patients with meningiomas operated at the University of Pittsburgh were analyzed. Cerebrospinal fluid leakage was the most frequent complication, observed in 25 patients (21%). Complications were more frequent in patients who had recurrent (previously operated) tumors and patients with extensive tumors. Our current analysis also indicates that patients with prior radio-therapy (usually external beam) have unacceptably high complication rates after microsurgery. Early results indicate that regrowth rates are much higher in patients with incomplete resection (20%) than those with gross total excision (5%). Of the 114 patients, 108 returned to independent living and/or their previous occupation.

Case report: colour Doppler demonstration of pseudoaneurysms complicating pancreatic pseudocysts.

The great morbidity and mortality associated with pseudoaneurysms complicating pancreatic pseudocysts stress the need for their early detection. The authors report the use of colour Doppler sonography in the detection of pseudoaneurysms within pancreatic pseudocysts, emphasizing not only the value of this modality in the initial diagnosis, but also its value in monitoring the success of transcatheter embolization. Colour Doppler should be used systematically in the evaluation of pancreatic pseudocysts.

MRI of acute disseminated encephalomyelitis after coxsackie B infection.

Acute disseminated encephalomyelitis (ADEM) is a rare demyelinating condition of the central nervous system, usually developing after a viral infection or vaccination. We report a case of ADEM predominantly affecting the spinal cord in an 8-year old boy evaluated by MRI. The radiographic picture consisted of multiple focal lesions of the spinal cord, a left posterior thalamic lesion and a subcortical right posterior parietal lesion. These lesions regressed several weeks after corticosteroid treatment. The clinical presentation, the laboratory results and the radiological findings suggest the diagnosis of ADEM secondary to viral infection by Coxsackie B.

Gadolinium-enhanced MR in the evaluation of preoperative meningioma embolization.

PURPOSE: To evaluate the use of postembolization gadolinium-enhanced MR imaging as a means to judge the efficacy of tumor embolization. METHODS: Fifteen patients with meningiomas were prospectively studied. The following data were evaluated for each tumor: the percentage of vascular supply to the tumor arising from the internal and external carotid arteries; the percentage of the tumor embolized as judged by angiography, by MR imaging, and by CT scanning; the estimated blood loss according to the surgeon; and histologic evidence of necrosis as seen by the neuropathologist. RESULTS: The data reveal an excellent correlation between the amount of tumor embolized as estimated by MR and both the estimated blood loss at time of surgery and the presence of histological necrosis in the specimen. CONCLUSIONS: Postembolization gadolinium-enhanced MR is an excellent means to evaluate the efficacy of an embolization and offers certain advantages over CT and angiography. One important advantage of this technique lies in the fact that it can be performed immediately postembolization.

Hydrosyringomyelia-Chiari I complex. Prospective evaluation of a modified foramen magnum decompression procedure: preliminary results.

A modified foramen magnum decompression procedure, designed to respect the subarachnoid spaces as much as possible, was prospectively evaluated in eight consecutive patients with a progressive clinical syndrome related to hydrosyringomyelia-Chiari I complex. This evaluation included quantitative clinical and magnetic resonance follow-up of at least 1 year in the first six patients and 6 months for the last two. Magnetic resonance scans at 6 months or more confirmed a persistent reduction of the hydrosyringomyelic cavity in all cases, which was associated with obvious subjective improvement. All patients have maintained this improvement. The operative technique and methods of clinical and radiological follow-up are discussed.

Gadolinium enhancement of vertebral endplates following lumbar disc surgery.

Gadolinium enhancement may be normal in the vertebral endplates adjacent to previously operated intervertebral discs. To determine the frequency of this finding and to differentiate this normal healing process from early lesions due to focal infection, we studied 135 patients who had undergone surgery for herniated lumbar disc, and compared them with 249 unoperated patients with radicular symptoms and 15 with known spondylodiscitis. Hypointense foci which enhanced with gadolinium were identified in the endplates of 25 (18.5%) of the operated patients, 9 of whom required a second operation for recurrent disc herniation, at which time the absence of infection was confirmed. Gadolinium enhancement within the endplates adjacent to the operated disc occurs during normal healing after surgery. Care should be taken before invoking a diagnosis of focal infection or secondary spondylodiscitis.

Stereotactic indications for neuroradiological differential diagnosis.

The modern neurodiagnostic techniques of MR imaging, CT scanning and angiography provide valuable morphological information that, although highly sensitive to tumour localisation, still lacks comparable specificity as to the exact histological nature of those lesions demonstrated. Biopsy remains necessary. To patients with potentially inoperable lesions or lesions best treated by chemotherapy or irradiation, modern techniques of neurosurgery now offer the option of precise stereotactic biopsy through small twist-drill burr holes as opposed to open biopsy. The interrelationships between MR, CT, angiography and stereotactic biopsy and their respective roles in the establishment of a definitive diagnosis are discussed.

Pineal cyst: normal or pathological?

Review of 500 consecutive MRI studies was undertaken to assess the frequency and the appearances of cystic pineal glands. Cysts were encountered in 2.4% of cases. Follow-up examination demonstrated no change in these cysts and they were considered to be a normal variant. Size, MRI appearances and signs associated with this condition are reported in order to establish criteria of normality.

Lipomyeloschisis associated with thoracic syringomyelia and Chiari I malformation.

Co-existence of Chiari I malformation and myelomeningocele is uncommon. Syringomyelia, when associated with a Chiari I malformation, classically involves the cervical spinal cord. Intramedullary extension of lipoma is unusual in lipomyeloschisis. A patient with lumbar lipomyelomeningocele with tethered cord, lower thoracic syringomyelia and Chiari I malformation, shown by MRI is reported.

Simultaneous neurofibroma and schwannoma of the sciatic nerve.

The authors report a case of simultaneously occurring neurofibroma and schwannoma of the sciatic nerve and discuss the complementary aspects of MR and US. The schwannoma was well-defined and showed distal enhancement on sonographic evaluation, whereas the neurofibroma was ill-defined; both tumors were hypoechoic. T1- and T2-weighted MR images revealed similar signal characteristics of the two tumors, but intense enhancement following administration of gadolinium-DTPA distinguished the schwannoma from the neurofibroma.