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.

Cortical brain microdialysis and temperature monitoring during hypothermic circulatory arrest in humans

OBJECTIVES

Critical vascular surgery of the brain or the heart occasionally requires total cessation of the circulatory system. Profound hypothermia is used to protect the brain from ischaemic injury. This study explores the use of microdialysis to measure metabolic indices of ischaemia: glutamate, lactate, and pH, and cerebral temperature during profound hypothermia and circulatory arrest.

METHODS

Effluent from a microdialysis catheter placed in the cerebral cortex of three patients undergoing complete circulatory arrest was continuously sampled. Samples were pooled over 10 minute periods and glutamate and lactate concentrations were measured postoperatively. Brain temperature and pH were measured on line intraoperatively. Electroencephalography and monitoring of somatosensory evoked potentials and brainstem auditory evoked potentials were simultaneously carried out.

RESULTS

Patient 1 had normal glutamate and lactate. PH was 6.75 to 6.85 and increased to 6.9 after warming ensued. Patient 2 had raised glutamate and lactate during most measurements. The glutamate concentrations peaked at 305 microM/l at the start of the measurements and fell below 20 microM/l after warming. The lactate concentrations peaked at 680 microM/l before cooling, rose to 1040 microM/l during the cooling process, decreased to 212 microM/l during circulatory arrest, and rose again to 620 microM/l after warming. The pH started at 7.06 and continued a downward course until stabilising at a pH of 6.5 after circulatory arrest. Patient 3 had a transient, mild increase in glutamate and lactate during the cooling and warming period. pH was stable throughout.

CONCLUSION

Microdialysis combined with temperature and pH measurements of the cerebral cortex promises to be an important tool in detecting cerebral ischaemia. Further studies are needed to validate our findings and test the feasibility of modifying ischaemic changes.

Saphenous vein graft reconstruction of an unclippable giant basilar artery aneurysm performed with the patient under deep hypothermic circulatory arrest: technical case report

OBJECTIVE AND IMPORTANCE

Effective treatment for unclippable giant vertebrobasilar aneurysms remains unclear. We present the first reported case of a giant vertebrobasilar aneurysm being successfully treated with trapping of the aneurysm and internal carotid artery to basilar artery bypass with a saphenous vein graft that was performed with the patient under hypothermic circulatory arrest.

CLINICAL PRESENTATION

A 15-year-old female patient with a history of probable subarachnoid hemorrhage and chronic headaches presented with a relatively acute exacerbation of her headache, nausea, vomiting, and weakness. Imaging studies revealed a 4 x 4 x 3-cm vertebrobasilar aneurysm, supplied by an angiographically dominant right vertebral artery and causing significant brain stem compression.

INTERVENTION

Initially, a petrosal approach with a hearing-preserving partial labyrinthectomy was used to perform a right external carotid artery to posterior cerebral artery bypass with saphenous vein. Delayed occlusion of the right vertebral artery with an intraluminal balloon was planned; however, intraoperative angiography revealed poor graft flow, presumably because of the small size of the posterior cerebral artery. Postoperative graft occlusion was anticipated. During this same time interval, the patient deteriorated neurologically. Brain imaging failed to reveal evidence of cerebral infarction. The patient underwent subsequent surgery. After a total petrosectomy, the aneurysm was trapped, an aneurysmectomy was performed, and, with the patient under deep hypothermic circulatory arrest, a new interposition saphenous vein graft was inserted between the internal carotid and basilar arteries. Excellent flow was observed angiographically. At her 4-month follow-up examination, the patient had improved to near baseline.

CONCLUSION

We present a technically challenging but safe and definitive treatment option for an unclippable giant vertebrobasilar aneurysm. Using cranial base approaches and hypothermic circulatory arrest techniques, aneurysmal trapping and successful bypass grafting directly into the basilar artery was performed.

Intraoperative on-line monitoring of cerebral pH by microdialysis in neurosurgical procedures

The objective of this study was to improve the ability to detect cerebrovascular complications in patients undergoing complicated neurosurgical procedures using on-line monitoring of cerebral pH with in vivo microdialysis. We employed on-line pH monitoring in patients with a variety of neurosurgical procedures including high-flow bypass surgery, aneurysm clipping, and temporal resection in epilepsy treatment. The pH was monitored with a microdialysis probe, usually inserted into the frontal cortex and pH of the dialysate was measured on-line with a pH electrode. We monitored 17 cases: 12 high-flow extracranial-intracranial (EC-IC) bypass procedures, 3 surgeries to clip large basilar tip aneurysms under protection of hypothermic circulatory arrest, and 2 surgeries for intractable seizure disorders. In the patients undergoing high-flow bypass, the pH remained stable in 5 patients and all had an uneventful outcome. In 3 patients, the pH decreased during surgery. One patient had a severe hemiparesis on awaking from anesthesia. The fall in pH in another patient was corrected when the blood pressure was raised during surgery. The pH was also responsive to changes in intraoperative ventilation and probably also to brain edema with elevation of pH values. In the three patients undergoing basilar tip aneurysm clipping under hypothermic circulatory arrest, the pH fell to 6.41 in one patient. This patient awoke with a mild hemiparesis. In the other two patients, the pH was stable during the hypothermia and neither patient had complications. In the patients undergoing temporal lobectomy and hippocampectomy, the pH fell rapidly with the onset of ischemia. We conclude that it is possible to monitor the cerebral extracellular pH with on-line microdialysis. The information obtained may alert the surgeon to the possibility of impending cerebral ischemia or other complications. However, further experience is needed before the technique can be recommended for general use.

Current Concepts in the Management of Tumors of the Skull Base

BACKGROUND: Due to their involvement with critical neurovascular structures, tumors located in the cranial base present challenges to neurosurgeons and are associated with high morbidity and mortality. METHODS: Rates of tumor control, complications, patient outcomes, and recurrences were extracted and summarized from two decades of our surgical and radiological treatment follow-up and review of the medical literature. RESULTS: Recent advances in surgical techniques involving cranial base approaches have made surgical intervention safer and curative resection more likely. In managing benign tumors, surgical resection is the gold standard for treatment. While immediate complications are still significant, long-term outcomes in most cases are excellent. Focused radiosurgery using a gamma knife or linear accelerator has produced favorable outcomes, and it improves the management of small or minimally symptomatic cranial base tumors. For slow-growing malignant tumors, extensive surgery followed by radiotherapy achieves the best outcome. In managing highly malignant tumors, outcome is determined by the effects of chemotherapy and radiotherapy. On some occasions, surgery is needed to obtain greater control of highly malignant tumors. CONCLUSIONS: Skull base tumors are relatively common, and management of these tumors is rapidly evolving. The combination of surgical excision using cranial base techniques, radiosurgery, fractionated radiotherapy, and chemotherapy should be individually tailored based on the location and pathological aggressiveness of the tumor and the symptomatology of the patient.

Acoustic neuromas: results of current surgical management

OBJECTIVE

In this article, we review the surgical outcomes of 179 patients with acoustic neuromas.

METHODS

Most of the tumors (84%) were operated on using a retrosigmoid, transmeatal approach. A transpetrosal, retrosigmoid approach was used in 10% of the patients, most of whom had large tumors. The translabyrinthine (4%) and transmastoid, transpetrosal, partial labyrinthectomy approaches (2%) were used selectively. The operative approaches are discussed. Tumors were categorized according to their cerebellopontine angle dimensions as small (< 2 cm), medium (2.0-3.9 cm), and large (> or = 4 cm).

RESULTS

House-Brackmann evaluation of postoperative facial nerve function revealed excellent results (Grade I or II) in 96% of small tumors, 74% of medium tumors, and 38% of large tumors. A fair postoperative function (Grade III or IV) was achieved in 4% of small tumors, 26% of medium tumors, and 58% of large tumors. Functional hearing preservation, defined as Gardner-Robertson Class I or II, was achieved in 48% of small tumors and 25% of medium tumors. Hearing was not preserved in any of the three patients with large tumors in whom hearing preservation was attempted. Treatment complications consisted mainly of cerebrospinal fluid leakage (15% of the patients). The majority of the patients who experienced cerebrospinal fluid leakage were treated successfully with lumbar spinal drainage; only four patients (2% of the total group) required subsequent surgery for correction of cerebrospinal fluid leakage. There were two deaths (1%) in this series. One death occurred as the result of myocardial infarction and the other as the result of severe obstructive lung disease. One patient sustained disability because of cerebellar and brain stem injury. Complete tumor resection was accomplished in 99% of the patients, and there was no evidence of recurrence in this group. Only 1 of the 179 patients underwent incomplete tumor resection; he required subsequent surgery for symptomatic tumor regrowth. Our patient follow-up had a mean duration of 70 months and a median of 65 months (range, 3-171 mo).

CONCLUSION

Our results are similar to those of other large microsurgical series of acoustic neuromas. Unless a patient has major medical problems, microsurgery by an experienced team of surgeons is preferred over radiosurgery.

Saphenous vein graft bypass of the sigmoid sinus and jugular bulb during the removal of glomus jugulare tumors. Report of two cases

Glomus jugulare tumors always invade the jugular bulb and sigmoid sinus, making it difficult to resect these tumors totally without sacrificing the involved sinus. Although the sinus can be sacrificed safely in most patients, a few patients will have serious consequences. Reconstruction of the jugular bulb using a saphenous vein graft may enable tumor resection in these patients without complications. The authors describe two cases of saphenous vein grafting used to bypass the sigmoid sinus. The first case is that of a 61-year-old man with a glomus jugulare tumor that invaded the dominant sigmoid sinus, which was poorly collateralized. Temporary occlusion of the sinus during surgery caused a 15-mm Hg increase in intrasinus pressure, without brain swelling or changes in evoked potentials. A saphenous vein graft was used to bypass the sigmoid sinus and jugular bulb and to allow for total tumor removal. The patient had a good outcome. The second case is that of a 41-year-old man with a left glomus jugulare tumor and another smaller tumor on the opposite, dominant sinus. The left glomus jugulare tumor was resected via a two-stage procedure. A saphenous vein graft was used to reconstruct the left sigmoid sinus because of the presence of contralateral disease, with the potential for bilateral sigmoid sinus occlusion. An evaluation of the venous collateral circulation during jugular foramen surgery and the prevention of complications are also discussed.

Repositioning of the vertebral artery as treatment for neurovascular compression syndromes. Technical note

Neurovascular compression syndromes are usually treated by interposing Teflon felt or padding or some other implant between the offending vessel and the nerves. However, this cannot be done in some cases in which ectatic vertebrobasilar arteries are involved. In these instances, alternative techniques must be used. The authors report the use of a sling made of Prolene to reposition the vertebral artery in two patients with neurovascular compression disorder. The clinical results were gratifying, with complete resolution of the patients' symptoms. Compression by large vessels is an uncommon but important source of neurovascular compression in patients with trigeminal neuralgia, hemifacial spasm, disabling positional vertigo, and, possibly, hypertension. The technique described may be useful to surgeons treating these problems.

EC-IC bypass improves chronic ischemia in a patient with moyamoya disease secondary to sickle cell disease: an in vivo microdialysis study

Patients with sickle cell disease may develop intracranial vascular disease, with the occlusion or obstruction of the large or small arteries, which may lead to the secondary development of moyamoya disease. In this report, we describe the neurochemical changes in the brain before, during, and after an extracranial-intracranial bypass procedure on a patient with sickle cell disease and a moyamoya disease like pattern on angiography. We used the in vivo microdialysis technique to measure the on-line pH, lactate and amino acid concentrations in the extracellular fluid. There were relatively high resting glutamate levels and a lower-than-normal pH in the extracellular fluid prior to the bypass, associated with chronic ischemia. During the bypass there was a short-lived increase in the glutamate levels. After revascularization, there was a rapid decrease in the glutamate levels and an increase in the pH value. The patient's preoperative neurological deficit improved post-operatively, corresponding to the biochemical changes towards normal values. These changes after revascularization suggest that chronic biochemical abnormalities due to brain ischemia may improve after cerebral revascularization.

Long-term follow-up of patients with meningiomas involving the cavernous sinus: recurrence, progression, and quality of life

OBJECTIVE

In this report, we evaluate the recurrence- and progression-free survival of patients with meningiomas involving the cavernous sinus.

METHODS

The rates of tumor recurrence and progression in 119 patients with meningiomas involving the cavernous sinus treated between 1983 and 1993 were analyzed.

RESULTS

The mean follow-up period was 33.8 months. There were seven recurrences of completely resected tumors (7 of 73, 10%) and seven progressions of incompletely resected tumors (7 of 46 15%). Life table analysis of recurrence- and progression-free survival was performed. The recurrence-free survival rate was 94% at 3 years and 81% at 5 years. In contrast, the progression-free survival rate was 87% at 3 years and 62% at 5 years (P = 0.0456). There were two patterns of recurrence or progression. The first group of tumors had an aggressive biological behavior with growth at multiple areas of resection; the second group showed growth at or near the margins of resection. Functional status continued to improve slowly during the follow-up period; however, there was no statistically significant difference between the Karnofsky scores obtained 3 to 12 months postoperatively and the follow-up Karnofsky scores (obtained > 1 yr postoperatively).

CONCLUSION

Surgery for meningiomas involving the cavernous sinus seems to provide excellent tumor control. Our experience suggests that for the majority of these tumors, complete tumor resection can be performed with acceptable risks of morbidity and mortality and seems to increase the duration of recurrence-free survival. The long-term quality of life of surviving patients is satisfactory, with the great majority of the patients being independent.

Enzyme-linked immunosorbent assay quantification of cytokine concentrations in human meningiomas

OBJECTIVE

To gain insight into the network of cytokine gene expression in the brain tumor microenvironment, we investigated the presence of the following cytokines in freshly excised brain tumors: interleukin (IL)-1 beta, IL-2, IL-4, and IL-6.

METHODS

Tumor specimens from nine meningiomas were grown as tissue explants. The supernatants from the explants were tested for the presence of the aforementioned cytokines via the enzyme-linked immunosorbent assay method.

RESULTS

IL-6, which is thought to stimulate acute protein phase synthesis, neovascularization, and cell proliferation, was found in all of the samples in greater concentrations than the other cytokines tested. IL-1 beta, another stimulatory cytokine thought to be involved in acute protein phase synthesis and cell proliferation, was also found in 100% of the samples tested, in concentrations significantly lower than those of IL-6. As expected, the presence of IL-2 and IL-4 was not detectable in any of the samples.

CONCLUSION

This study is the first to clearly determine the relative concentrations of IL-1 beta and IL-6, using enzyme-linked immunosorbent assay quantification. These findings are an important precursor to future studies using antibodies to IL-1 beta and IL-6 and antibodies to IL-6 receptors to modulate neoplastic growth both in vitro and in vivo.

Petroclival and foramen magnum meningiomas: surgical approaches and pitfalls

The management of petroclival and foramen magnum meningiomas has been revolutionized by the techniques of cranial base surgery. However, these tumors are still among the most difficult cranial base lesions to treat. In this report, we discuss the classification, presenting symptoms, preoperative investigation, treatment indications, operative approaches and technique, postoperative complications and care, and results of surgery of petroclival and foramen magnum meningiomas. Careful analysis of tumor- and patient-related factors has helped us to predict which features can lead to postoperative problems in patients allowing surgeons to appropriately modify their behavior. The application of cranial base techniques-combined with new knowledge about the limitations of microsurgical resection-can greatly reduce postoperative morbidity in these patients.

Treatment of aneurysms by excision or trapping with arterial reimplantation or interpositional grafting. Report of three cases

The authors report three cases of ruptured, large or giant aneurysms that were treated by excision or trapping, followed by revascularization of distal vessels by means of arterial reimplantation or superficial temporal artery interpositional grafting. In the first case, a large serpentine aneurysm arising from the anterior temporal branch of the right middle cerebral artery (MCA) was excised and the distal segment of the anterior temporal artery was reimplanted into one of the branches of the MCA. In the second case, a giant aneurysm, fusiform in shape, arose from the rolandic branch of the MCA. This aneurysm was totally excised and the M3 branch in which it had been contained was reconstructed with an arterial interpositional graft. In the third case the patient, who presented with a subarachnoid hemorrhage, had a dissecting aneurysm that involved the distal portion of the left vertebral artery. In this case the posterior inferior cerebellar artery (PICA) arose from the wall of the aneurysm and coursed onward to supply the brainstem. This aneurysm was managed by trapping and the PICA was reimplanted into the ipsilateral large anterior inferior cerebellar artery. None of the patients suffered a postoperative stroke and all recovered to a good or excellent postoperative condition. These techniques allowed complete isolation of the aneurysm from the normal blood circulation and preserved the blood flow through the distal vessel that came out of the aneurysm. These techniques should be considered as alternatives when traditional means of cerebral revascularization are not feasible.

Management and long-term outcome of adenoid cystic carcinoma with intracranial extension: a neurosurgical perspective

Adenoid cystic carcinoma is a tumor of minor and major salivary glands that often invades the cranial base and intracranial cavity via local and perineural spread. In the past, the role of neurosurgeons in managing these tumors has been limited. The growth of interdisciplinary cranial base surgical approaches has now increased the involvement of neurosurgeons in the management of these tumors. We present a series of 16 patients with adenoid cystic carcinomas with cranial base and intracranial extension, the largest series reported in the neurosurgical literature. We have focused our approach on a neurosurgical perspective and made recommendations for the treatment of these tumors in relation to the following specific aspects of this disease. 1) The management of the carotid artery: In our experience, when the carotid artery is involved by tumor, a preliminary cerebral revascularization procedure with a cervical carotid to middle cerebral artery vein bypass graft should be performed before tumor resection. 2) The management of the cavernous sinus and orbit: Cavernous sinus tumor should be removed as fully as possible, but every effort should be made to preserve the IIIrd and IVth cranial nerves to achieve optimal functional and cosmetic results. The orbit should be exenterated when there is intraconal involvement; otherwise, intraorbital tumor can be removed with orbital preservation. 3) The use of palliative surgery: We have found that the use of palliative surgery can be considered even in patients whose extent of local disease precludes a surgical cure. The slow progression of the disease allows for long-term survival of many patients with advanced local disease and even of those with metastatic disease. 4) The long-term survival of these patients: In our series, six patients had no evidence of local disease and a mean survival of 72 months, one living patient had evidence of local disease and has survived 56 months, eight patients died of disease, with a mean survival of 137 months, and one patient died of complications after surviving for 63 months.

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.

Transcranial Doppler ultrasonography in neurosurgery: effects of intracranial tumour on right middle cerebral artery flow velocity during induction of anaesthesia

The right middle cerebral artery flow velocity (MCAFV) was measured by transcranial Doppler ultrasonography in neurosurgical patients with and without intracranial tumours during anaesthetic induction and endotracheal intubation. With institutional and patient consent, 20 non-tumour and 85 tumour-bearing neurosurgical patients were enlisted. The right middle cerebral artery was insonated with a pulsed-wave range-gated transcranial Doppler at 2 MHz, and MCAFV was recorded via a video graphics printer. The mean MCAFV, pulsatility index, use of anaesthetic drugs, heart rate, mean arterial pressure, and endtidal CO2 were recorded on preinduction, postinduction, intubation, and 90 to 180 s postintubation. There was no demographic, systemic haemodynamic, or anaesthetic difference between groups except for a predominance of women in the tumour group. In all patients, mean arterial pressure and MCAFV demonstrated with time a significant decrease with anaesthetic induction, increase with endotracheal intubation, and decrease post intubation. The right MCAFV was significantly higher in both tumour and right-sided tumour patients compared to non-tumour patients. There was no difference in left-sided tumour patients compared to non-tumour patients. These data indicate that intracranial tumours have cerebrovascular effects, causing either hyperaemia or vasoconstriction, and that the effects of anaesthetic induction and intubation agree with previously reported effects on cerebral blood flow and intracranial pressure.

The results of surgery for benign tumors of the cavernous sinus

CAVERNOUS SINUS SURGERY has been performed increasingly in the last 2 decades because of new knowledge and technologies. With increasing international expertise in cavernous sinus surgery, the results must be analyzed critically to search for accurate prognosticators of outcome. We performed a retrospective review of 124 patients (40 male, 84 female; mean age, 45 years) who underwent cavernous sinus surgery for benign tumors from 1983 to 1992. Sixty-five percent had tumors encasing the internal carotid artery. Mean follow-up was 29 months (median, 26 mo). Gross total or near-total resection was possible in 80%. Patients with neurilemomas, angiofibromas, epidermoids, chondroblastomas, and hemangiomas were more likely to have total or near-total resection (100% versus 75%, P < 0.025). Disabling complications (five cerebral infarctions, two meningitis, and one hydrocephalus with chiasmal prolapse) occurred only in patients with meningiomas or pituitary adenomas. On follow-up, excellent/good binocular vision was achieved in 53% of patients entering surgery with excellent/good function versus 25% who entered surgery with fair/poor binocular vision (P < 0.025). Ninety-three percent of patients had a Karnofsky score > or = 70 on follow-up. There were a total of 12 recurrences (10%), 6 in patients with meningiomas, 2 in patients with angiofibromas, 2 in patients with craniopharyngiomas, 1 in a patient with a pituitary adenoma, and 1 in a patient with an osteoblastoma. Patients with tumor growth or neurological symptoms indicative of progressive cavernous sinus involvement should undergo cavernous sinus exploration. This surgery has acceptable morbidity and mortality and, if the tumor can be removed easily, the surgeon should try to perform radical tumor resection. To avoid major complications, the surgeon must exercise utmost care to preserve the neurovascular structures of the cavernous sinus, with special attention to tumors that extend into the petroclival region. Better results from surgery can be expected in those patients with neurilemomas, hemangiomas, or epidermoids than in patients with meningiomas, craniopharyngiomas, or pituitary adenomas. Good functional outcome can be expected, particularly if the patient's preoperative clinical status is good. Particular attention must be paid to the reconstruction of anatomic barriers in order to prevent cerebrospinal fluid leakage and subsequent meningitis.

Chordomas and chondrosarcomas of the cranial base: results and follow-up of 60 patients

The management of chordomas and chondrosarcomas involving the cranial base remains controversial. The options for therapy include biopsy, partial resection, radical resection, and various forms of radiotherapy. In this article, we analyze the outcome of 60 patients with cranial base chordoma or chondrosarcoma treated with extensive surgical resection between 1984 and 1993. Forty-six patients had chordomas, and 14 had low-grade chondrosarcomas; 50% of these patients had been treated previously. Preoperative studies included computed tomography, magnetic resonance imaging, cerebral angiography, and balloon occlusion test of the internal carotid artery, as indicated. Magnetic resonance imaging was performed on all patients during follow-up. The surgical approaches used for tumor resection were predominantly the following: subtemporal, transzygomatic, transcavernous, and transpetrous apex; subtemporal and infratemporal; extended frontal; and extreme lateral transcondylar. Staged operations with a combination of approaches were used when necessary (52% of cases) to remove a tumor more completely. Statistical analysis was done by the chi 2 test and correlation matrix. Sixty-seven percent of the patients had total or near-total resection. Twenty percent of the patients received postoperative radiotherapy. Eleven patients died during the postoperative follow-up period, nine with chordomas and two with chondrosarcomas. Three patients died because of systemic complications within 3 months after surgery, five died because of tumor recurrence, one died from unrelated causes, and two died from late complications of radiotherapy. The recurrence-free survival rate for all tumors was 80% at 3 years and 76% at 5 years. Chondrosarcomas had a better prognosis than chordomas (recurrence-free survival rates, 90% at 5 years and 65% at 5 years, respectively; P = 0.09). Patients who had undergone previous surgery had a greater risk of recurrence (5-year recurrence-free survival rate, 64%) than did patients who had not undergone previous surgery (5-year recurrence-free survival rate, 93%; P < 0.05). Patients with total or near-total resection had a better 5-year recurrence-free survival rate (84%) than did patients with partial or subtotal resection (64%) (P < 0.05). Postoperative leakage of cerebrospinal fluid was the most frequent complication (30% of patients) and was found to increase the risk of permanent disability. Patients who had undergone previous radiotherapy had a greater risk of death in the postoperative period (within 3 months of their operations) and during follow-up. However, total or near-total resection did not increase the rate of postoperative disability.(ABSTRACT TRUNCATED AT 400 WORDS)

Temporary balloon test occlusion of the internal carotid artery: experience in 500 cases

PURPOSE

To describe experience with 500 temporary balloon occlusions of the internal carotid artery, with particular emphasis on the techniques and complications.

METHODS

Temporary occlusion of the internal carotid artery was accomplished endovascularly using various balloon-catheter combinations. These temporary balloon occlusions were combined, when possible, with cerebral blood flow analysis with stable xenon-enhanced CT.

RESULTS

Complications related to this procedure occurred in 16 (3.2%) patients. Eight (1.6%) patients had asymptomatic complications. There were 8 who experienced neurologic changes. Six (1.2%) of these were transient; two (0.4%) were permanent. There were no deaths.

CONCLUSIONS

Temporary balloon occlusion of the internal carotid artery, believed helpful in identifying patients at risk of stroke during abrupt carotid artery sacrifice, can be performed with an acceptably low complication rate.

Surgical excision of meningiomas involving the clivus: preoperative and intraoperative features as predictors of postoperative functional deterioration

Neurological deterioration is commonly seen after surgical excision of clival meningiomas; however, an understanding of the risk factors associated with postoperative deterioration can lead to improvements in outcome. In 75 patients with clival meningiomas operated on over a 7-year period, the following data were studied; preoperative variables such as presenting Karnofsky scale score, age, sex, and prior operations or radiation therapy. Radiological findings on magnetic resonance imaging or arteriography, such as the development of the arachnoidal cleavage plane between tumor and the brain stem, brainstem edema, tumor size, extent of compression on the brain stem, vascular encasement, and blood supply from the basilar artery were among other data studied. In addition, intraoperative findings such as development of the arachnoid plane, vascular encasement, and the difficulty of dissection were noted. Finally, each patient's neurological and functional statuses were recorded at 1 week postoperatively and at follow-up examinations. Early postoperative functional deterioration occurred in 45 patients (60%) and ranged from mild (30 patients) to severe (three patients). Significant improvement had occurred by the time of follow-up examination in all but four patients; however, permanent postoperative dysfunction was present in 12 patients. Statistical analysis revealed significant correlations between early functional deterioration and preoperative Karnofsky scale scores, male gender, radiological findings of the absence of an arachnoid plane, edema of the brain stem, and arteriographic supply from the basilar artery. Operative features included difficulty with dissection, an absent arachnoidal cleavage plane, and incomplete tumor resection. Permanent functional deterioration was statistically associated with the following: blood supply from the basilar artery, difficulty of dissection, incomplete tumor resection, and early postoperative dysfunction. Logistical regression analysis revealed that the most important risk factor for early postoperative deterioration was tumor size. Patients with large or giant tumors had a 6.7 to 13 times greater risk of functional deterioration, respectively, than patients with small- or medium-sized tumors. Excluding tumor size, the most important factor for permanent deterioration was blood supply from the basilar artery. Patients in this category had a 4.4 times greater risk of permanent functional deterioration. Three stages of tumor relationship to the brainstem arachnoid and pial membranes are proposed. Based on the results of this clinical study of clival meningiomas, suggestions are made for changes in the management strategy of these difficult lesions.

Cranial base approaches to intracranial aneurysms in the subarachnoid space

The use of cranial base approaches to aneurysm surgery is illustrated by means of patient examples. Over a 9-year period, cranial base approaches were used to expose and treat 38 aneurysms involving the anterior communicating artery complex, proximal internal carotid artery, basilar artery, or vertebral artery. The approaches included orbital osteotomy, orbitozygomatic osteotomy, petrous apicectomy, presigmoid petrosectomy, and extreme lateral transcondylar methods. Complications related to the approaches included one partial ptosis and two cerebrospinal fluid leaks, which resolved with treatment. The technique of three-dimensional computed tomographic angiography was useful in delineating the vascular anatomy and its relation to the cranial base structures. This helped the surgeon plan the appropriate approach to the aneurysm. Cranial base approaches, used selectively, can provide improved exposure of deep-seated aneurysms and large or giant aneurysms, while minimizing brain retraction.

Infiltration of the carotid artery by cavernous sinus meningioma

Intracranial meningiomas are known to infiltrate surrounding structures such as the calvaria and dural sinuses, and the brain itself. The issue of whether meningiomas invade major intracranial arteries is of clinical importance, particularly in the case of meningiomas of the cavernous sinus. If a meningioma has not invaded the carotid artery wall, complete tumor removal may be accomplished with careful dissection from the carotid artery; however, if the tumor has infiltrated the wall of the carotid artery, complete removal may require sacrifice of the artery. To determine whether cavernous sinus meningiomas invade the carotid artery, the authors retrospectively reviewed the histopathology of 19 consecutively treated individuals whose carotid artery was sacrificed during removal of a meningioma involving the cavernous sinus. Patients were selected for carotid artery resection based on preoperative magnetic resonance imaging studies demonstrating complete encasement of the artery. Reconstruction of the carotid artery was planned depending on the results of preoperative balloon test occlusion with blood flow determinations. None of the 19 patients had pathological evidence of malignant tumor. Eight individuals (42%) were found to have infiltration of the carotid artery by meningioma. In five cases, focal involvement of the adventitia of the carotid artery wall was noted and, in three, the vessel was infiltrated up to the tunica muscularis. In no case was the tunica muscularis invaded by tumor. Thus, meningiomas of the cavernous sinus do infiltrate the internal carotid artery and, in order to completely resect these lesions and effect a surgical cure, it may be necessary to sacrifice the carotid artery with or without reconstruction.