Germinoma located in the basal ganglia in an 8-year-old girl

CASE REPORT

The authors describe a unique case of an 8-year-old girl with a germinoma located in the left basal ganglia. Medical history begins 5 months before with a central diabetes insipidus, loss of weight (5 kg at admission), vomiting and asthenia. Computed tomography (CT) and cranial magnetic resonance imaging (MRI) are performed and demonstrate a left basal ganglia tumour (nucleus lentiformis). Diabetes insipidus is considered as non-visible germinoma localization on the pituitary stalk rather than as a possible consequence of peri-tumoural oedema surrounding the hypothalamus. Spinal MRI is normal. Neurological as well as general examination is normal.

DISCUSSION

The first hypothesis is low-grade glioma, but pathological examination following a stereotactic biopsy of the lesion reveals a cerebral germinoma. A few days before the biopsy, the girl experienced a mild left facial palsy, and CT scans at the time of biopsy reveals an intra-tumoural haemorrhage. Alpha fetoprotein and human chorionic gonadotrophin were negative as blood and cerebrospinal fluid markers, whereas placental alkaline phosphatase was positive on immunohistochemical profile of the tumour samples. Dedicated chemotherapy, followed by focal irradiation (40 Gy, 30 sessions, 45 days; SIOP CNS GCT 93 protocol), is performed with a complete response. The outcome is good (Glasgow Outcome Scale=I), without any cognitive impairment and the persistence of a mild facial palsy and a slight right arm dystonia on last neurological examination. There is still no evidence of tumour recurrence.

Nano-alpha-Al2O3 by liquid-feed flame spray pyrolysis

Nanometre-sized particles of transition (t)-aluminas are important for the fabrication of high-quality alumina ceramics. Multiple tons are produced each year using a variety of gas-phase processes. The nanoparticles produced by these methods consist mainly of the undesired delta phase with some gamma- and theta-Al(2)O(3). Nano-t-aluminas should provide access to dense nano/submicrometre-grained alpha-Al(2)O(3) shapes offering significant advantages over micrometre-grained shapes. Unfortunately, polymorphism coupled with the high activation energy for nucleating alpha-Al(2)O(3) greatly impedes efforts to process dense alpha-Al(2)O(3) with controlled grain sizes, especially for submicrometre materials. Typically alpha-Al(2)O(3) nucleation within t-aluminas is sporadic rather than uniform, leading to exaggerated grain growth and vermicular microstructures without full densification (5). Thus, production of quantities of nano-alpha-Al(2)O(3) from multiple nano-t-aluminas for seeding or direct processing of alpha-Al(2)O(3) monoliths could greatly change how alpha-Al(2)O(3) components are processed. We report here that liquid-feed flame spray pyrolysis of nano-t-aluminas converts them to dispersible 30-80 nm alpha-Al(2)O(3) powders (50-85% phase transformed). Surprisingly, the powder surfaces are fully dehydrated. These powders pressureless sinter to more than 99.5% dense alpha-Al(2)O(3) with final grain sizes < or =500 nm without sintering aids.

[Methylation status of RARbeta gene promoter in low and high grade cerebral glioma. Comparison with normal tissue. Immuno-histochemical study of nuclear RARbeta expression in low and high grade cerebral glioma cells. Comparison with normal cells. 48 tumors]

Retinoic acid receptor beta (RARbeta) is a nuclear receptor often deregulated in tumors. An immunohistochemical study was conducted to examine the level of expression of this receptor in the nucleus of glial cell tumors (low and high grade glioma) as well as a study of the methylation status of the gene promoter coding this receptor on the same tumor samples. A comparison with normal tissue was done each time. 48 tumors were eligible for the study (15 glioblastomas, 20 grade III oligodendrogliomas and 13 grade II oligodendrogliomas). A constant decrease of RARbeta expression was found by comparison with normal tissue whatever the histological grade of the tumor, suggesting a deregulation of RARbeta gene expression. Methylation of RARbeta promoter gene was a rare event (12.5% of all cases), except for grade III oligodendrogliomas (20%), and is thus not a major event of this gene deregulation. Other reasons of this deregulation of RARbeta should be studied, such as loss of 3p24 heterozygoty, mRNA studies and RARbeta interactions with other retinoid receptors.

Neurosurgical concepts and approaches for orbital tumours

Orbital tumours are lesions that appear within the orbital craniofacial borders. To this end, treatment of these tumours is assured by teams of different specialists. Furthermore, these pathologies are different in adults and in children. We have endeavoured, in this chapter, to highlight the specifically neurosurgical features of orbital tumours or, to be more precise, tumours affecting the posterior two thirds of the orbit and tumours originating in or intruding into the optic canal. The list of aetiologies is long. After recapitulating the main types of tumour (as well as those of most concern), we have also studied the different stages of surgery, namely approaches and reconstructions which we have illustrated at each stage by a tumour that, in our view, seemed emblematic of the problem in question: the lateral eyebrow approach for schwannoma and cavernous angioma, the transorbital subfrontal approach for optic nerve glioma, the pterional and orbital approaches for spheno-orbital meningioma, problems with reconstruction and with plexiform neurofibroma affecting the orbit and fibrous dysplasia of bone.

Thalamic ependymal cyst presenting with tremor

CASE REPORT

We report the case of a 6-year-old boy presenting with intention tremor. CT and MR scanning showed a large thalamic cyst.

TREATMENT

Stereotactic tapping of this cyst was carried out as the first step in surgical management. Following drainage of the cyst the tremor disappeared, but recurred 18 months later. Repeat MRI showed that the thalamic cyst had refilled. As the initial tapping of the cyst had resulted in effective but only transient clinical improvement a cysto-peritoneal shunting procedure was performed.

OUTCOME

The clinical symptoms again disappeared and the child has now remained tremor free for 3 years.

Individualized treatment of craniopharyngioma in children: ways and means

BACKGROUND

Medium- and long-term prognosis of craniopharyngioma is overwhelmed by the risks of hypothalamic and visual impairment. This problem has been underestimated for a long time because the major concern for the neurosurgeon was the risk of recurrences, their best prevention being thought to be complete tumour resection. Today, we know that radical surgery not only is not an absolute guarantee against recurrences but also can cause hypothalamic and visual complications.

METHODS

The authors suggest that instead of complete removal, the first choice treatment should be, when possible, a less aggressive, multistaged and personalized treatment. In this perspective they focus on other therapeutic methods: endocavity treatment of cysts with rhenium-186, triconformational radiotherapy, radiosurgery, and widespread use of the trans-sphenoidal approach.

CONCLUSIONS

These simple methods should reduce the risks of visual aggravation and metabolic syndrome.

Acute spontaneous hemorrhage after embolization of brain arteriovenous malformation with N-butyl cyanoacrylate

PURPOSE

To investigate factors predisposing to spontaneous hemorrhage in the early period after embolization of brain arteriovenous malformations (AVMs).

METHODS

The authors report 15 cases of spontaneous hemorrhage in a consecutive series of 492 brain AVMs totally or partially treated with intranidal injections of a polymerizing mixture, from 1984 to June 1998. Retrospective analysis of the records was performed with special attention to the angio-architectural features before embolization, details of embolization procedures and induced angiographic modifications.

RESULTS

Pre-embolization features of greater incidence were the presence of steal phenomena (87%), multiple feeding arteries (100%), a compact aspect of the nidus (93%), and lobar topography (87%). In most cases the volume of injected glue exceeded 1 ml (80%), venous embolization was significant (67%) and immediate angiographic control showed venous stagnation in and/or around the nidus (80%). Four patients were asymptomatic (incidental discovery on systematic CT at day 3). Among the remaining 11 symptomatic patients, 6 were operated to evacuate an intracerebral hematoma, outcome was good for 4, 5 were left with sequelae and 2 died.

CONCLUSION

Spontaneous hemorrhagic complications affected 3.04% of embolized patients. The combination of certain angio-architectural features, significant venous embolization and persistent venous stagnation within the nidus seem to have some predictive value of high risk hemorrhage. In light of this, additional preventive measures must be taken and a neurosurgical team systematically kept on standby.

Chemotherapy for unresectable and recurrent intramedullary glial tumours in children. Brain Tumours Subcommittee of the French Society of Paediatric Oncology (SFOP)

Adjuvant treatment for intramedullary tumours is based on radiotherapy. The place of chemotherapy in this setting has yet to be determined. Between May 1992 and January 1998, eight children with unresectable or recurrent intramedullary glioma were treated with the BB SFOP protocol (a 16-month chemotherapy regimen with carboplatin, procarbazine, vincristine, cyclophosphamide, etoposide and cisplatin). Six children had progressive disease following incomplete surgery and two had a post-operative relapse. Three patients had leptomeningeal dissemination at the outset of chemotherapy. Seven of the eight children responded clinically and radiologically, while one remained stable. At the end of the BB SFOP protocol four children were in radiological complete remission. After a median follow-up of 3 years from the beginning of chemotherapy, all the children but one (who died from another cause) are alive. Five patients remain progression-free, without radiotherapy, 59, 55, 40, 35 and 16 months after the beginning of chemotherapy. The efficacy of this chemotherapy in patients with intramedullary glial tumours calls for further trials in this setting, especially in young children and patients with metastases.

[Dysembryoplastic neuroepithelial tumors. Analysis of 16 cases]

OBJECTIVES

We report on 16 cases of dysembryoplastic Neuroepithelial tumor (DNT) treated in the Nancy University Hospital from 1987 to 1997.

PATIENTS AND METHODS

There were 9 males and 7 females. Mean age at onset of symptoms was 9.5 years (range: 3 months to 29 years) and the mean age at surgery was 16 years. Nine patients experienced partial complex seizures, 5 patients generalized seizures, 1 patient partial seizures with secondary generalization and one patient ataxia. The diagnosis of DNT was made under consideration of clinical, radiological and neuropathological features. All patients underwent surgery.

RESULTS

Removal of the tumor was complete for 10 patients, subtotal or partial for 6 patients. Histological examination revealed that 7 cases were specific forms of DNT due to the presence of the specific glioneuronal element. For the 9 remained cases, the diagnosis of DNT could only be made with the consideration of clinical and radiological features. Mean post-surgical follow-up was 3.5 years (range: 1-8 years). Eight patients were seizures-free, 7 had a significative reduction in seizures frequency with minimal anti-convulsivant treatment. The patient with ataxia remained unchanged. For the patients with partial resection of the tumor, follow-up MRI and CT scan showed no significant growth of the remnant and the remaining patients have had no recurrence to date.

CONCLUSION

The recognition of this surgically curable entity is mandatory. Knowledge of the good prognosis associated with the DNT is essential to avoid deleterious side effects of overtreatment by radiotherapy and/or chemotherapy.

[Intrasellar epidermoid cysts]

Two patients presenting with an intrasellar epidermoid cyst and operated on through a transsphenoidal approach, are reported. Problems regarding pathological controversies about the differential diagnosis (particularly craniopharyngiomas) are addressed. In order to establish the adequate preoperative diagnosis, the interest of MRI is discussed.

[Endovascular treatment of vasospasm]

Cerebral vasospasm remains a leading cause of heightened morbidity and mortality rates following aneurysmal subarachnoid hemorrhage despite the apparent benefit of recent medical therapeutics. Successful resolution of medically refractory angiographically demonstrated vasospasm with concomitant reversal of delayed neurological deficit has been observed after balloon angioplasty. Subsequent reports confirmed these encouraging results but also emphasized the limitations of the technique and the risks of complications. Intraarterial papaverine infusion has been performed for the treatment of diffuse cerebral vasospasm with controversial results and has also been combined with angioplasty either to facilitate balloon navigation or to treat arteries inaccessible to balloon catheterization. All these different endovascular approaches explain the confusion existing about the indications, timing and efficacy of the endovascular treatments. This article reviews several clinical and experimental studies dealing with these questions.

Prognostic factors in pediatric spinal cord astrocytoma

BACKGROUND

Factors that could optimize the management of pediatric spinal cord astrocytoma remain unclear and controversial.

METHODS

To determine the factors that influence the prognosis of pediatric patients with spinal cord astrocytomas, a series of 73 consecutive patients at 13 French treatment centers with histologically proven spinal cord astrocytomas was retrospectively reviewed. Hospital records, operative records, and results of radiologic investigations were available in all cases. Follow-up was achieved in 94% of cases.

RESULTS

Seventy percent of the patients had low grade (1 or 2) tumors. Total or subtotal surgical resection was achieved in 43%. Thirty-six patients were irradiated following surgery. Fifty-one patients were alive at a median follow-up of 54 months. Twenty-three patients relapsed. Univariate analysis showed that good outcome was correlated with male gender, age younger than 7 years, duration of presenting symptoms longer than 2 months, the presence of spinal deformities, and low grade histology, whereas sensory loss was associated with decreased survival. Multivariate analysis using the Cox proportional hazards model confirmed that histology (relative risk [RR] = 7.69) and the interval between first symptoms and diagnosis (RR = 4.93) were significant independent prognostic factors. The extent of surgery or radiotherapy had no clear influence on survival.

CONCLUSIONS

This review sheds light on the prognoses of pediatric patients with spinal cord astrocytomas and may help to determine therapeutic strategies based on patients' clinical, radiologic, and pathologic features.

[An exceptional variety of medulloblastoma: melanotic medulloblastoma]

We report a new case of melanotic medulloblastoma of the vermis in a 3 1/2 year old boy. This tumor showed a typical histological appearance with pseudoepithelial pigmented structures immunoreactive for S100 protein and vimentin. The tumor did not recur after total surgical removal and post operative radiation. However, after a 10 year follow-up, imaging demonstrated that a second tumor occurred in the left cerebellar hemisphere, which, on histological examination, was a typical glioblastoma. Hypothesis concerning the histogenesis of the second tumor, as well as a causal association with radiation therapy and possible contribution of growth hormone therapy are discussed.

[Meningiomas of the sellar diaphragm. Apropos of 4 cases]

Since 1987, we have treated four patients with diaphragma sellae meningioma. Tuberculum sellae meningiomas with intrasellar extension were strictly excluded from this retrospective study. A complete tumor removal was performed in two patients. The two other patients underwent post-operative radiotherapy. According to the Kinjo's classification, the four meningiomas were classified as follows: one type A (supradiaphragmatic-prepituitary), one type B (supradiaphragmatic-retropituitary), one type C (subdiaphragmatic), one type not described in this classification characterized by sub and supradiaphragmatic extension. Based on our experience and data in the literature, the clinical and neuroradiological features of the diaphragma sellae meningiomas are reviewed. Diaphragma sellae visualization at MRI, which is not always possible, allows to localize the tumor on a supra- or infra- diaphragmatic position and to decide the optimal surgical approach. The diaphragma sellae is more visible on protonic density, or T2-weighted sequences, but can be located on T1-weighted images. Appropriate surgical approaches are the sub-fronto-pterional route for supradiaphragmatic meningiomas and the transsphenoidal approach for subdiaphragmatic meningiomas.

Arteriovenous malformations of the corpus callosum--radioanatomic study and effectiveness of intranidus embolization

Forty-three patients with arteriovenous malformations (AVMs) of the corpus callosum treated by embolization were reviewed. The following clinical and radioanatomic characteristics were found: 84% (36 patients) presented with intracranial hemorrhage, 43% (20 nidi) of the lesions were located in the posterior half of the corpus callosum, multiple nidi were more frequent (21%) than expected, 27 nidi (59%) were fed by branches of both the anterior and posterior cerebral arteries, AVMs mainly drained into the internal cerebral vein and/or interhemispheric superficial veins, and 19 (41%) had both draining pathways, 10 patients (23%) had impaired drainage through the straight sinus due to dysplasia. Staged embolization was performed in 245 feeders. Curative occlusion (more than 95%) was obtained in 17 patients (40%) and considerable occlusion (more than 75%) in 33 patients (77%). Large and giant, diffuse-type, and multifocal AVMs were difficult to completely embolize. Complications associated with embolization occurred in six patients, mostly during the first 5 years. Only two patients had a permanent deficit related to a complication. Overall morbidity and mortality were 7% and 2%, respectively. Nine patients were referred for stereotactic radiosurgery, three of whom were completely cured and five patients have not been assessed. Most AVMs in the corpus callosum are supplied by multi-axial feeders, so multi-target intranidus embolization is very important to prevent the development of other feeders secondary to the hemodynamic shift. Combined therapy using maximum embolization and subsequent radiosurgery may be the most effective method to treat AVMs in the corpus callosum.

Endovascular occlusion of intracranial aneurysms of the posterior circulation: comparison of balloons, free coils and detachable coils in 38 patients

We treated 38 patients with 39 aneurysms of the posterior circulation by an endovascular technique using balloons, free coils or Guglielmi detachable coils (GDC) from 1986 to May 1993. The patients ranged in age from 10 to 71 years. Subarachnoid haemorrhage was the most frequent presentation (29 patients), followed by mass effect (5 patients) and epilepsy (2 patients). Treatment consisted of embolisation of the aneurysm with preservation of the parent vessel (in 29) or occlusion of the parent vessel (in 5). Multiple procedures were performed in 12 patients (32%, maximum 3 embolisations, total 17 treatments), because of incomplete initial aneurysm occlusion (in 8 cases) or re-opening of the aneurysm (in 9). Treatment could not be achieved in 5 patients. Good to excellent aneurysm occlusion was obtained in 28 patients (72%). Little or no neurological impairment occurred in 31 patients (82%). Complications related to treatment (11 patients, 29%) included 4 cases of transient cerebral ischaemia, 7 of stroke resulting in minimal neurological impairment (in 5), severe impairment (in 1) and one death. There were 6 patients who died, of rebleeding from the same aneurysm (2), basilar stroke (1) and unrelated causes (3). Comparison of the different occlusion techniques showed that the best angiographic results were obtained with balloons (good to excellent aneurysm occlusion was obtained in 17 of 22 patients treated) and the GDC (12 of 13 patients), and that less good results were given by free coils (4 of 9 patients). Complications related to treatment were fewest in patients treated with GDC (1 of 16 treatments, including multiple procedures) or free coils (2 of 12 treatments) and were more frequent with balloons (6 of 27 treatments). All five treatment failures occurred with balloon embolisation, whereas treatment was possible in all cases treated with free coils or GDC.

Aneurysm clipping after endovascular treatment with coils: a report of eight patients

Between January 1990 and December 1994, patients with subarachnoid hemorrhage related to ruptured aneurysms who were referred to our institution were treated by neurosurgical and neuroradiological teams. In each patient, the respective indications for neurosurgical or endovascular treatment were discussed, taking into consideration patients' age and the morphological and topographical aneurysm features. We report eight cases of patients with subarachnoid hemorrhage who underwent operations after primary endovascular procedures (Hunt and Hess scores III, IV, and V). The indications for surgical treatment were as follows. First, deliberate partial occlusion of the aneurysm (two aneurysms of the internal carotid artery and one aneurysm of the anterior communicating artery) was performed to obtain only partial clotting of the aneurysm sac by free coils. However, this procedure was discontinued in favor of the use of Guglielmi detachable coils. The second indication was partial occlusion after an endovascular procedure (two aneurysms of the middle cerebral artery and one internal carotid artery aneurysm). The third indication was re-expansion of the aneurysm 1 year after the endovascular treatment (one middle cerebral artery aneurysm). The final indication was secondary rupture of the aneurysm sac and false aneurysm around the migrating coil (one aneurysm of the pericallosal artery). During surgery, the aneurysm sac appeared translucent. The coils bulged out and stretched the aneurysm sac. One ruptured the membrane leading to a subarachnoid hemorrhage during the endovascular procedure. No hemorrhage occurred during the surgical clipping. Aneurysm obliteration was easily performed, especially when the packing was partial, but was very difficult when the complete aneurysm closure led to a stenosis of the parent vessel. A giant sylvian aneurysm rest, visible only with angiography, was left untreated. This series illustrates an original experience, which led us to conclude that aneurysm surgery with coils in place is not as difficult as is often thought.

[Subarachnoid hemorrhage caused by aneurysm rupture. Surgery or embolization?]

Traditionally the aneurysms of the circle of Willis have been an indication for neurosurgery. New technologies of endovascular treatment with electrically detachable coils resulted in a different therapeutical concept since four years. A series including 140 patients has been treated in our institution from 1 January 1992 to 31 December 1994, 94 of them presenting with a subarachnoid haemorrhage. Out of these 140 patients, 84 were treated with surgery, 51 with the endovascular technique, five with surgery after incomplete or unsuccessful endovascular treatment. Surgery was indicated in patients presenting early after bleeding, devoid of vasospasm, with a favourable Hunt and Hess grading and in aneurysms located in the anterior part of the circle of Willis. Endovascular treatment was indicated in patients admitted with delay, with severe vasospasm, a poor Hunt and Hess grading and in all aneurysms of the vertebrobasilar arterial network. Age was of less importance in comparison to the status of the vessels for selection of the method of treatment. Giant aneurysms are difficult to treat as surgery is faced with the size of the aneurysmal itself and endovascular technique with the width of the aneurysmal neck.

[Spinal epidural cavernous angioma. Apropos of 2 cases. Review of the literature]

We report 2 cases of spinal epidural cavernous angiomas revealed by paraplegia, and present the main cases reported in the literature since 1895. The diagnosis of this uncommon affection seems to be difficult to establish only upon clinical and radiological features. In spite of recent advances in neuroradiological imaging, these kinds of angiomas still remain an operative and histopathological discovery. A laminectomy was performed revealing a vascular lesion which was totally extirpated. Functional recovery was achieved in both cases.

[Endovascular treatment of intracranial aneurysms]

Major improvements have been achieved in endovascular treatment of intracranial aneurysms during the last twenty years. Initial techniques of selective balloon occlusion were progressively replaced by the packing of the aneurysmal pouch with very small and soft metallic devices, named coils, with controlled detachment. In some rare cases, balloon occlusion is still used in order to occlude the parent vessel or to reverse the flow, especially in the vertebro-basilar system. Essential aims for the anaesthesiologist include: complete immobility of the patient throughout the endovascular procedure, systemic anticoagulation in order to avoid any thromboembolic complication during and after treatment, prevention and/or treatment of vasospasm, precise evaluation of fluid balance during the procedure. Our experience is based on 145 aneurysms in 135 patients, treated by endovascular route; 91 (63%) of them were revealed by a subarachnoid haemorrhage (SAH). Their main locations were: the carotid siphon (33.1%), the anterior communicating artery (19.3%), the basilar artery (17.2%) and the middle cerebral artery (17.2%). Thirty-seven of these aneurysms (25.5%) were very small in size with a diameter less than 4 mm. Total or sub-total (more than 90%) occlusion was achieved in 141 aneurysms (90.3%). Thromboembolic complications occurred in eight patients (5.9%), neurological sequelae in one. Other treatment-related complications included the migration of a coil outside the aneurysm in six cases (4.4%) without neurological deficit in one and five ruptures of the aneurysm (3.7%) during the procedure with one lethal issue due to the spontaneous bleeding of a controlateral arterio-venous malformation. Thirteen patients died (9.6%). The cause of the death was related on the initial SAH in 11 of them. The two others were both due to rupture: of a second untreated aneurysm in one case and of an associated arteriovenous malformation in the second one. At present the main indications of endovascular treatment are poor or non indications for neurosurgery. Due to the quality of results, endovascular therapy will be more and more used in case of ruptured or non ruptured aneurysms.

[Endovascular treatment of vasospasm]

Various therapeutic strategies have been recently proposed to prevent the vasospasm after subarachnoid haemorrhage, and to avoid its clinical consequences. Despite these progresses, mortality and morbidity of delayed ischaemic consequences of vasospasm remain important. Two endovascular treatments have been proposed. The successful use of transluminal angioplasty for vasospasm was first reported by Zubkov in 1984. Transluminal angioplasty is very effective with clinical improvement when the treatment is undertaken without delay after the onset of symptoms. Limitations of this technique are the inaccessibility of distal arteries and the risks (vascular rupture or occlusion). More recently, to overcome these limitations, a selective intraarterial infusion of papaverine has been proposed. These infusions are less risky and can be employed in distal vasospasm. However, clinical results seem to be less favourable and often transient. These two techniques are still used with slightly different indications. According to our experience, it seems reasonable to reserve transluminal angioplasty for symptomatic vasospasm, associated with papaverine or not, and to use papaverine alone in all other cases.

[Pericranial sinus]

This study concerns four cases of sinus pericranii observed at the Neurological Department of Nancy. Sinus pericranii is a direct communication between the outer surface of the skull and the intracranial venous sinuses. It may be congenital, acquired or traumatic. This abnormality, usually located in the midline and often in the frontal region, is usually symptomless, but some patients complain of headache, nausea and vertigo. Sinus pericranii shows as a fluctuating non pulsatile mass of reddish or bluish colour, expanding when the patient bends his head down. Radiography usually shows one or several bone defects opposite the lesion found at CT bone window. On soft tissue window the mass is not calcified and usually enhanced by contrast injection. It is sometimes possible to visualize the vascular communication between the extracranial region and the underlying dural sinus. When visualization is blurred, or CT shows intracerebral abnormalities, MRI examination is required. Angiography with subtraction in venous phase (40 to 60 seconds after the injection), sometimes aided by films taken in head down position. It is of interest only in cases where CT and MRI have shown associated vascular abnormalities. Otherwise, direct injection of contrast medium into the malformation makes it possible to assert the diagnosis of sinus pericranii and to determine the flow rate within the malformation, which to some extent commands the the therapeutic technique. In patients with small and asymptomatic sinus pericranii absention is the rule. When the sinus is of moderate size, and the flow rate not rapid and when there is no significant communication with the cerebral veins, endovascular sclerosis may be advocated. In all other cases, surgical removal is recommended and is usually easy.

Dissection of intracranial vertebral arteries revealed by subarachnoidal haemorrhage. Report of seven cases

Between April 1986 and April 1991, seven cases of meningeal haemorrhage consecutive to dissection of the 4th segment of a vertebral artery were observed at the Neuroradiology Department of the Nancy University Hospital. Four of the 7 patients were men, and 3 were women; mean age varied from 45 to 61 years. The clinical presentation was not suggestive, except in one case where the haemorrhagic episode was associated with Wallenberg's syndrome, pointing to the aetiological diagnosis. The outcome was variable. Two patients died of early complications of the haemorrhage which occurred before treatment could be given. In 2 others patients treated with antiplatelet agents the outcome was favourable; however, at angiography the lesions regressed in one of these two patients, but they progressed in the other with formation of a false aneurysm. The remaining 3 patients were treated by endovascular occlusion of the lesion-bearing vessel: one died of complications of a haemorrhage-induced vasospasm; the other two are symptomless after a 2 to 6 months follow-up.

Aneurysm associated with a fenestrated basilar artery: report of two cases treated by endovascular detachable balloon embolization

The authors report two cases of aneurysms originating at a fenestration of the basilar artery treated by endovascular placement of a balloon inside the aneurysm with preservation of the patent vessel.

[Surgery for lumbar disk hernia after chemonucleolysis. Results and analysis. Apropos of 100 cases]

We studied the clinical results of 100 patients operated after failure of chemonucleolytic treatment with chemopapain for lumbosciatica caused by disk herniation. Secondary surgical procedures were performed because of persistence of sciatic pain and disk herniation visible on CT scan. Post-operative follow-up was done at a minimum of one year. Clinical results were analyzed according to the criteria of Mac-Naff. Out of 100 patients who were re-operated, there were: 14% excellent results, 38% good results, 26 mediocre results, and lastly 22% failures or worsening of the condition. Thus 52% satisfactory compared to 75-95% when surgery is done immediately; 48% of the results were unsatisfactory or worse than before. We analyzed the mechanism of action of papain and suggested a pathophysiological explanation for these results. We concluded that chemonucleolysis with chemopapain cannot be an intermediary step between systematic medical treatment and surgical treatment.

Role of angioplasty in the treatment of symptomatic vascular spasm occurring in the post-operative course of intracranial ruptured aneurysms

Angioplasty of vascular spasm (VS), related to subarachnoid hemorrhage (SAH) has been recently introduced to the medical field. The authors report 5 cases treated by this mean in the postoperative period. These patients were all symptomatic from their VS inspite of early surgery and of the preventive treatment by Nimodipine. In all cases, obtained increase in the caliber of the spastic vessels was followed by a rapid clinical improvement coupled with a significant decline of the flow rates as confirmed by transcranial Doppler (TCD). No recurrence of VS has been observed. This technique appears quite effective provided that it is performed as early as the clinical symptoms come out in correlation with important acceleration of flow rates on TCD.

[Value of transcranial Doppler in the monitoring of aneurysmal subarachnoid hemorrhage treated with calcium inhibitors]

Fifty four patients (33 male and 21 female, mean age 47) with spontaneous aneurysmal subarachnoid hemorrhages have been tested by repeated TCD: 25 of them were systematically administered intravenous Nimodipine when admitted at hospital, the 29 others constituted a reference group. There was no statistically significant difference between the two groups of patients for age, sex, initial clinical status, importance of bleeding at CT scan, localization of aneurysm or existence of an angiospasm, whether clinically symptomatic or not. In 72% of the cases, TCD allowed to prove the existence of an angiospasm when higher flow velocity was registered in cranial basal arteries. There was no significant difference between the two groups. The final clinical status of the patients seemed to be more favourable in the treated group. Yet it did not appear to be directly linked to the existence of a spasm or not. This argued in favour of a non-univocal mechanism of action of Nimodipine.