Pathophysiology, clinical manifestations and supportive care of metastatic brain cancer.

Brain metastases (BrM) are tumours that originate in tissues outside the central nervous system and spread secondarily to involve mainly the brain. The management of patients with cerebral metastases is complex, costly, and in some instances controversial. Furthermore, even in patients with widespread systemic cancer, the symptoms of the disease are often controllable while the symptoms of the BrM may be disabling. The treatment of BrM is one of the few areas of neuro-oncology where real progress has been made in the last twenty years. Moreover, the costs of managing this disease are rising, as therapies become more intensive and the number of patients with BrM increases. Modern neuroradiological imaging techniques, which are able to discover BrM earlier in the course of systemic cancer, and the greater efficacy of specific treatments, which lengthens survival, have increased the prevalence. The aggressive treatment of BrM may add some benefits to the patient, but its excessive cost leads to the necessity for accurate cost-effectiveness analysis. The latter begins with a complete understanding of the disease: its diagnosis, natural history and results of various modalities of treatment. While the development of BrM usually indicates a poor prognosis for the patient, advances in supportive care have made it possible to reverse most of the neurological symptoms and to give patients a meaningful extension of useful life.

Surgical treatment of intracranial dural arteriovenous fistulae: role of venous drainage.

OBJECTIVE: This report focuses on the surgical management of aggressive intracranial dural arteriovenous fistulae (d-AVFs), which are defined as fistulae with arterialized leptomeningeal veins (red veins). Particular attention is paid to the accurate identification of the venous drainage pattern and to the choice of the proper treatment strategy. METHODS: Thirty-four consecutive patients with aggressive intracranial d-AVFs were treated between 1994 and 1998. Angiographic studies allowed the identification of two main types of aggressive lesions, i.e., d-AVFs with sinus drainage and reflow into leptomeningeal veins (12 patients), which we designated sinus fistulae, and d-AVFs drained exclusively by leptomeningeal veins without sinus interposition (22 patients), which we designated nonsinus fistulae. All patients underwent surgical treatment, which consisted of resection of the fistulous sinus tract in 12 cases of sinus fistulae and interruption of the draining veins at their dural origin in 22 cases of nonsinus fistulae. Surgical preparation via multistage transarterial embolization was required in all 12 cases of sinus fistulae and in 4 of 22 cases of nonsinus fistulae. RESULTS: The mortality rate was 0%, and there were no instances of lasting morbidity. Radioanatomic cures were achieved in all cases. There was no case of venous hypertension or venous infarction after resection of the affected sinus or interruption of the draining veins. No arteriovenous shunts recurred during the follow-up period. CONCLUSION: Careful preoperative identification of the venous drainage pattern seems critical for planning of the correct surgical strategy to treat aggressive intracranial d-AVFs. If the fistula exhibits sinus drainage with reflow into leptomeningeal veins, surgical excision of the fistulous sinus segment represents a safe and definitive treatment option. In these cases, the affected sinus may be safely removed, provided that preoperative angiograms demonstrate participation of the sinus in drainage of the lesion, indicating that the sinus is nonfunctional. Conversely, if the fistula exhibits pure leptomeningeal drainage, the sinus does not participate in drainage of the lesion and cannot be excised. In these cases, the best treatment involves interruption of the draining veins at the point at which they exit the dural wall of the sinus. This simple easy treatment has been proven to be safe and highly effective in permanently eliminating arteriovenous shunts.

Transbasal approaches to aneurysms of the vertebro-basilar junction.

The most difficult aneurysms to be surgically treated are those of the vertebro-basilar junction area. This is due to their deep location and the proximity of brain stem and cranial nerves. Recently, new transbasal surgical approaches have been developed in order to realize a shorter and more direct access. Clival lesions, such as neoplasms, angiomas, and aneurysms, can now be safely faced through these routes. In this paper, we report our recent experience in transbasal approaches for the management of six consecutive patients, with aneurysms in this area. In four of these patients, the initial treatment consisted of an attempt at endovascular aneurysm obliteration using the Guglielmi Detachable Coil system, whereas, in the other two patients (basing on age, aneurysm size and neurological conditions), surgery was considered as the treatment of choice. Unfortunately, the endovascular treatment failed in all cases, and all patients had to be eventually operated on. In all cases, surgical clipping was performed through the combination of a transmastoid (asterional) approach with the suboccipital lateral approach. By this route, in all cases, parent arteries proved well delineated, the aneurysms could always be correctly clipped. Good long-term results were achieved in all cases but one. When surgery is to be performed, the importance of a thorough wide exposure of the whole vertebro-basilar junction area, as well as the importance of having multiple accesses to the lesion, cannot be overemphasized.

Multidisciplinary (surgical and endovascular) approach to intracranial aneurysms.

In spite of the availability of the new endovascular technique (GDC) to manage cerebral aneurysms, to date, the crucial question "which is the proper treatment in a given patient?" still remains unsettled. In order to check whether an answer is possible, we retrospectively reviewed a personal series of 192 consecutive patients with cerebral aneurysms (1993-1995). We found 164 patients who had been considered eligible for active aneurysm treatment. Treatment modality has been chosen case by case on the basis of patient conditions, and aneurysm size and location. Four groups of patients were identified: Group 1: 104 patients (63.4%) with subarachnoid hemorrhage (SAH) in whom the treatment of choice was surgery; Group 2: 27 SAH patients (16.4%) in whom the first choice was GDC; Group 3: 7 SAH patients (4.2%) who died before the scheduled treatment; Group 4: 26 patients (15%) with not ruptured aneurysm who had either surgery or GDC. Based on the results of this series (improvement of the overall results through the multidisciplinary approach), we have developed the guidelines to prospectively manage future cases of cerebral aneurysms with the purpose to rationalize the management, thus further improving the overall results.

Aneurysms of the vertebro-basilar junction area: preliminary experience in endovascular and surgical management.

Aneurysms of the vertebro-basilar junction area have been considered the most difficult to be surgically treated because of their deep location, the proximity of the brain stem and the cranial nerves. However, at present, new endovascular techniques and new transbasal surgical approaches offer valuable management strategies. This paper concerns six consecutive patients whom we managed either endovascularly or surgically during a period of eighteen months. Direct surgical treatment was offered to two young patients with relatively small aneurysms in good neurological condition, whereas the other four patients initially underwent an endovascular attempt at aneurysm obliteration using the Guglielmi detachable coil system. Unfortunately, interventional neuroradiology failed in three cases, and surgery had to be re-considered. Accordingly, a total of five patients underwent surgical clipping through the combination of a transmastoid retrolabyrinthine approach with the suboccipital lateral approach. This combination of approaches provided a good control of both vertebral arteries and basilar artery, and allowed the aneurysm to be correctly clipped in all cases. Good long-term results were achieved in all cases but one. Based on this preliminary experience, we would stress the importance of multidisciplinary approach with a treatment calibrated for each single case. Furthermore, if surgery is to be performed, the combination of transmastoid-retrolabyrinthine and suboccipital lateral approaches provides a wide exposure of the whole vertebro-basilar junction area and allows good access to the lesion.

Comparison of pediatric and adult cerebral arteriovenous malformations.

The authors report 19 consecutive children with cerebral arteriovenous malformations over the period 1978-1992. These patients are compared with a series of 120 consecutive adult patients with the same pathology, managed during the same period. The main clinical and angiographic features, as well as the treatment modalities and outcome are reviewed and compared. Children seem to harbour smaller and simpler lesions than adults. Furthermore, despite a more severe clinical presentation, children appears to fare better than adults. The possibility of evolution of brain arteriovenous malformations is discussed.

"High risk" anterior basal skull fractures. Surgical treatment of 64 consecutive cases.

Anterior Basal Skull Fractures (ABSFs) may be complicated by Cerebrospinal Fluid (CSF) fistulae and intracranial infections. An initially non-operative management is usually suggested since most fistulae spontaneously stop within a few days thus requiring no surgical repair. However, if the fistula fails to stop or recurs, surgical treatment is to be considered. Furthermore, if the fracture is complicated by meningitis, there is a relative risk of recurring infections and surgical repair may be also considered. Finally, surgical repair may be suggested in cases of compound, comminuted, depressed, largely extended cranio-facial fractures (the so-called "fracas craniofaciaux") where spontaneous healing is considered unlikely and risk of infection is high. Accordingly we termed "high risk" fractures those associated with active (persistent or recurring) cerebrospinal fluid fistula, those with meningitis and the so-called "fracas craniofaciaux". In this paper, we report our personal experience in surgical treatment of 64 consecutive "high risk" anterior basal skull fractures. Thirty-seven patients had persistent or recurring fistulae, ten had intracranial infections and seventeen had severe bone derangement of the anterior skull base. The osteodural repairs were performed through bilateral or unilateral subfrontal approach. In 59 cases the initial procedure was successful whereas 4 patient needed additional surgery but were ultimately successfully treated. One patient died. No major permanent neurologic or neuropsychologic impairments were reported. On the basis of our experience, we think that intracranial repair is a very suitable treatment modality in facing "high risk" anterior basal skull fractures.

Spontaneous haematoma as unusual complication of silastic dural substitute. Report of 2 cases.

Two cases of an unusual complication of synthetic duraplasty are reported. In both cases, patients had been operated on because of meningiomas and dural defects had been repaired with Silastic. Some years later they developed severe graft-related haematomas and were ultimately successfully treated only by the removal of the synthetic grafts. On the basis of this and other clinical experiences, biological dural grafts seem to be preferable to synthetic ones.

Combined surgical approach to coexistent carotid and coronary artery disease.

Combined coronary artery bypass and carotid endarterectomy were performed in 52 patients (mean age 61 years) between 1981 and 1990. Of these, 36 (69%) had functional class III-IV angina pectoris, 33 (63%) had triple-vessel disease, 36 (69%) had one, or more, previous myocardial infarctions, and 33 (63%) had an abnormal left ventricular function. In 4 cases, additional cardiac procedures were performed. Asymptomatic carotid stenosis was documented in 29 patients (56%) and the remaining 23 (44%) had experienced cerebrovascular symptoms. All patients had hemodynamically significant stenosis of at least one carotid artery, 17 (33%) had severe bilateral carotid artery stenosis, and 6 (11%) had an additional occlusion of the contralateral internal carotid artery. There were no early deaths. Perioperative morbidity included: myocardial infarction in 4 patients (7.7%) and neurological deficit in 3 (5.7%) but functional impairment was not permanent. Late results have been obtained for all 52 patients at a mean postoperative interval of 35 months. Four patients (7.7%) have died, and the 5 year life-table survival rate was 83%. At five years, actuarial curves showed 67% of patients to be free of all serious events or death. Late mortality and morbidity were related above all to the progression of the coronary artery disease. We concluded that simultaneous endarterectomy of significant carotid artery stenosis in candidates for coronary bypass can be done safely and considered as more practical for the patient.

Foramen magnum decompression versus terminal ventriculostomy for the treatment of syringomyelia.

The A.A review 30 consecutive cases of syringomyelia operated on during the last seven years. Six terminal ventriculostomies (TV) and twenty-seven procedures for foramen magnum decompression (FMD) were performed. All patients of TV group had CT-myelography (CTM) and/or NMR controls at different times after surgery. Clinical results are as follows: 1) of the 6 patients who had TV, only one showed an improvement while five continued to deteriorate and three of them needed a FMD, one a cysto-peritoneal shunt and the last one died from lung cancer. 2) of the 27 patients who had FMD, twenty improved, four were unchanged and three worsened. 3) no surgical deaths occurred in this series. Postoperative NMR monitoring represents an effective non-invasive neuroradiological procedure that allows follow-up of syrinx evolution over the years.

Superficial temporal artery to proximal middle cerebral artery anastomosis: clinical and angiographic long term results.

Anastomosis of the superficial temporal artery (STA) with a proximal segment of the middle cerebral artery (MCA) has been proposed as a new cerebral revascularization technique alternative to the conventional bypass on the cortical surface. We introduced this procedure in our surgical practice in 1982 for patients with internal carotid artery (ICA) aneurysms not suitable for direct repair in whom occlusion of the ICA is considered necessary. One patient died because a conventional STA-MCA bypass did not prevent a major stroke caused by a therapeutic ICA occlusion. We are reporting our surgical technique and the immediate and long term clinical and angiographic results in five cases operated on during the period June 19, 1982, through January 19, 1983. The early and late patency rates were good. No neurological complications were observed after the bypass procedure or during a 3-year follow-up period. In our opinion, the use of proximal segments of the MCA as recipient arteries for supratentorial revascularization is a good alternative to the use of cortical surface arteries and, in selected cases, could be the first choice technique.

Role of EEG monitoring and cross-clamping duration in carotid endarterectomy.

The usefulness of electroencephalographic (EEG) monitoring as well as the significance of the period of cross clamping in carotid endarterectomy have not been completely defined. In particular, the clinical importance of major EEG changes has not been fully investigated and some recent studies seem to indicate that the method has little value. As to the duration of cross clamping, there is strong evidence that occlusion times of about 15 minutes are tolerated under general anesthesia, but no information is available regarding longer periods of occlusion. The authors describe a consecutive series of 141 carotid endarterectomies in which the patients with EEG changes were shunted only when occlusion was anticipated to last longer than 30 minutes. Early major EEG changes (during the first 4 minutes) occurred in 14% of the cases. In the absence of EEG changes, long occlusion periods of 40 to 50 minutes were well tolerated. In contrast, the 20 patients with major persistent EEG changes did not tolerate protracted occlusion and three of them had immediate postoperative neurological complications. It seems that, in these circumstances, the incidence of neurological deficit is a function of the duration of cross clamping: these three patients had undergone occlusion for 15 to 30 minutes. Their deficits partially resolved. On the basis of these results it is concluded that: EEG recording is a reliable monitoring system in carotid artery cross clamping. No major strokes due to temporary carotid artery occurred in the series. The clinical significance of major persistent EEG changes is not negligible. Cross clamping for longer than 15 minutes in the presence of significant EEG alterations is potentially dangerous.

Complications after subclavian-cortical middle cerebral artery bypass.

Subclavian-cortical middle cerebral artery bypass by saphenous vein interposition is an uncommon recent revascularization technique used for immediate volume flow to the brain or when donor arteries are unavailable or inadequate. We used this technique in four cases of symptomatic common carotid artery occlusion. In the last two cases, severe, reversible neurological complications occurred. We think that these complications are due to this particular technique, and more cautious indications than for traditional extra-intracranial arterial bypass are recommended.