[Intrasellar arachnoid cysts: computed tomography and MRI. Apropos of 2 cases]. / Kystes arachnoïdiens intrasellaires: scanographie et IRM. A propos de deux observations.

We describe the computed tomographic and magnetic resonance imaging findings in two cases of intrasellar arachnoid cysts. The diagnosis of intrasellar arachnoid cyst with suprasellar extension should be evoked in case of a cyst-like formation whose density and signal appear to be identical to those of the cerebrospinal fluid even if contrast uptake is evidenced in the cyst wall. Contrast uptake can be related to compression of the pituitary stalk and normal pituitary displacement. Suspected intrasellar arachnoid cyst modifies the surgical approach which must be made via a subfrontal route. We discuss the differential diagnosis with other intrasellar cystic formations such as necrosed tumor, abscesses, Rathke pouch cysts, cystic craniopharyngiomas, epidermoid cysts and parasite cysts.

Vertebral haemangiomas with spinal cord compression: the place of preoperative percutaneous vertebroplasty with methyl methacrylate.

We report on cervical and two thoracic vertebral haemangiomas with neurological disturbance successfully treated by percutaneous vertebroplasty followed by decompression surgery. Vertebroplasty consolidates the vertebral body and reduces the risk of haemorrhage. Subsequent surgery may be limited to decompressive laminectomy and resection of the epidural extension of the haemangioma. embolisation was also carried out in one case. Complete neuroimaging workup, including CT, myelo-CT and MRI, is necessary prior to treatment.

[Lumbar disk hernia. Excision of hernia with or without complementary diskectomy?]. / Hernies discales lombaires. Herniectomie avec ou sans discectomie complémentaire?

The authors compare the limited removal of the ruptured disc to discectomy for lumbar disc herniation. Analysis of results during a four years period demonstrates a twice higher recurrence rate with limited removal than with discectomy and a more frequent residual low back pain, after limited removal of the ruptured disc. These data made then limit the indications of the simple ruptured disc removal technique, with the exception of some specific anatomical locations: the migrated disc situated anterior or posterior to the ligament, without an associated discal bulging.

Thoracic intradural arachnoid cyst: possible pitfalls with myelo-CT and MR.

A thoracic intradural arachnoid cyst presenting as an intradural extramedullary mass highly suggestive of psammoma on myelogram and myelo-CT is reported in a 34-year-old female. High densities of the cyst were related to collection of contrast media within the cyst. However MR examination of the thoracic spinal cord including sagittal T1 (without and with contrast) and T2 studies failed to demonstrate the mass. Lack of MR changes were related on one hand to the small size of the cyst and to the absence of mass effect on the spinal cord, and on the other hand to a CSF-like signal of the contents of the cyst. Only combination of myelography, myelo-CT and MR allows precise diagnosis of small intradural arachnoid cyst; however MR is the method of choice for evaluation of large intradural subarachnoid cysts.

L5 radicular pain related to lumbar extradural gas-containing pseudocyst. Role of CT-guided aspiration.

L5 radicular pain related to an epidural gas-containing pseudocyst is described in a 62-year-old female. Transient resolution of radicular pain was observed after CT-guided gas aspiration. Recurrent radicular pain led to surgical treatment; after operation the radicular pain disappeared.

Therapeutic trial of intravenous nimodipine in patients with established cerebral vasospasm after rupture of intracranial aneurysms.

The therapeutic efficacy of intravenous nimodipine to treat the syndrome of delayed ischemic deterioration or vasospasm after subarachnoid hemorrhage caused by a ruptured aneurysm was investigated in a randomized, double-blind, placebo-controlled multicenter study. A total of 188 patients (nimodipine (N) = 102, placebo (P) = 86) were enrolled in the study, both pre- and postoperatively, within 24 hours of clinical deterioration connected with vasospasm or within 24 hours of arteriography that identified vasospasm. After 61 patients were excluded for not meeting study criteria or for protocol violation, the results were supported by 127 validated case reports: 73 patients received intravenous treatment with nimodipine, and 54 were given placebo. Analysis of the main criterion of efficacy, the number of deaths and of patients with severe deficit related to vasospasm alone, showed a significant statistical difference (N = 8 (19%), P = 17 (49%), P = 0.01). The risk of death or disability was reduced by 66% in the treated group. Analysis of this criterion by type of inclusion (clinical or angiographic) also showed a significant reduction in the clinical group (P = 0.05), but there was no difference in the angiographic group. The risk of mortality connected with vasospasm was reduced by 82%, but analysis by group showed that there was no significant difference for those patients included on clinical criteria, whereas mortality was reduced to a much greater extent in the angiographic group. These results demonstrate the therapeutic efficacy of nimodipine in reducing secondary ischemic brain damage in patients already suffering from angiographic vasospasm or delayed ischemic deterioration.

[Treatment of vasospasm in aneurysmal meningeal hemorrhage using intravenous nimodipine. Multicenter cooperative study]. / Traitement curatif du vasospasme des hémorragies méningées d'origine anévrysmale par la nimodipine intraveineuse. Etude coopérative multicentrique.

We present a multicentric randomized double-blind study of the curative effect of intravenous Nimodipine on the post hemorrhagic vasospasm after aneurysmal rupture. On 122 validated cases out of 188 analyzed patients, the study demonstrates a significative effect on the mortality and severe morbidity related to vasospasm: the reduction of the risk is appreciated to 72%. The major effect is obtained on the mortality risk. A selective effect can be demonstrate on the isolated vasospasm.

Review of treatment of symptomatic cerebral vasospasm with nimodipine.

A number of randomized studies have shown the efficacy of nimodipine, administered either orally or intravenously, for the prevention of vasospasm and its clinical consequences in patients with subarachnoid haemorrhage following rupture of an intracranial aneurysm. It remained to be proven that nimodipine could also act on already established vasospasm. This was the aim of a multicentre study carried out in France between 1984 and 1986. Of a total of 127 patients with known clinically and/or angiographically diagnosed vasospasm, 73 (group N) underwent intravenous treatment with nimodipine and 54 (group P) with placebo within 24 hours of the onset of vasospasm. There was shown to be a significant reduction in mortality and morbidity in group N (33%) compared with group P (52%). Where vasospasm was the sole determining factor (63% of all patients), the decrease in mortality and severe morbidity rate was even greater in group N (11%) compared with group P (31.5%). These results can be viewed as confirmation of the efficacy of nimodipine in treating the ischaemic consequences of established vasospasm.

[Histopathology of microsurgical arterial repair. Use of fibrin cryoprecipitates]. / Histopathologie de la réparation artérielle microchirurgicale. Apport des cryoprécipités fibrineux.

The increasing practice of small arteries anastomosis especially in neurosurgery entails improvements in suture techniques. Classical suture is slow and needs a prolonged clamping. The stitches are responsible for severe necrotic lesions in the arterial wall. A biological glue made of cryoprecipitated human fibrinogen, factor XIII and fibronectin, locally activated by thrombin, is tested here on rabbit's common carotid. The application of the glue on intact or sectioned arteries appears innocuous, notably with regard to its thrombogenic potential. Comparison of classical sutures and sutures with glue and a greatly reduced number of stitches shows histological results of equivalent quality. At the early stages, the fibrin glue doesn't exceed in volume the usual perianastomotic hematoma. It is completely resorbed within two weeks. Later the scar is thinner than after classical suture, although no ruptures or aneurysms were observed. This method shortens the surgical procedure, with presumed benefit for the drained territories. It diminishes the lesions caused by the stitches. Moreover it allows an easy application of an arterial patch on the sectioned vessel: a comparative series with sutured patches shows on the contrary poor results. Although aggresive for the tissues, a minimal number of stitches remains necessary: it is actually the only available means of correctly positioning the anastomosis area.

Soft cervical disc herniations.

The authors report their findings in a series of 51 patients suffering from typical cervical radiculopathy. With the aid of the CT scanner and intravenous injection of a contrast medium, the quality and resolution of the resulting images allowed neurosurgical intervention in 42 patients in whom the symptomatology alone was not sufficiently informative to allow successful treatment. In most cases the CT images allowed an accurate diagnosis and revealed a free fragment that had torn the common posterior vertebra ligament.

[Sarcoidosis of the anterior optic pathways. A diagnostic discussion]. / La sarcoïdose des voies optiques. Discussion diagnostique.

Two anatomo-clinical cases of neuro-ophthalmic sarcoidosis are reported where recognition of systemic involvement was delayed because unusual and quite isolate visual symptoms were present. The first patient had granulomas involving the intracranial optic nerve, presenting as optic nerve glioma. The second case presented as a chiasmal syndrome sharing unusual perimetric evolution. This binasal hemianopsia was probably the consequence of pre-chiasmal circulatory changes. Neuro-ophthalmic sarcoidosis should be included in the differential diagnosis of any involvement of the anterior visual pathways since these localizations are not as rare as was formerly thought. Improved awareness of this condition is a result of better neurodiagnostic studies by computed tomography which was not accurate enough a few years ago.

[Proximal temporo-sylvian anastomosis with an arterial cuff glued with fibrin. Technical, anatomical and arteriographic considerations]. / L'anastomose temporo-sylvienne proximale avec coiffe artérielle collée à la fibrine. Considérations techniques, anatomiques et artériographiques.

The authors present a new method of temporo-sylvian anastomosis used 8 times since 1982. This anastomosis called proximal is done on the insular segment (M2) of the sylvian artery and gives better revascularizations than the classic method (M4 or distal). The arterial cuff and the fibrin glue simplify, accelerate and improve the usual microsuture. A good knowledge about the microsurgical anatomy of the middle cerebral artery and its variants is important. The proximal sylvian artery and its perforators (50% occlusion in our cases) may be explored by this approach.

Sacral meningeal arteriovenous fistula fed by branches of the hypogastric arteries and drained through medullary veins.

The authors report a new case of intraspinal extra-medullary meningeal arteriovenous fistula draining through medullary veins. Discovered in a 33-year-old black man suffering from a cauda equina syndrome, this malformation suspected in myelography was confirmed by a selective angiographic procedure of both internal iliac arteries. This investigation specified the sacral site of the fistula as well as its feeding arteries from several branches of the left and right internal iliac arteries and its posterior and intra-meningeal venous medullary drainage. An embolization procedure followed by a surgical approach and a second embolization session brought a fair improvement to this young patient who could walk again. The acquired traumatic origin of the fistula is discussed for this patient who had been previously operated at his L5-S1 level.

[Congenital anomalies at the emergence of lumbosacral roots]. / Les anomalies congénitales de l'émergence des racines lombosacrées.

Thirteen of 45 cases of congenital anomalies of the lumbosacral nerve roots at their site of emergency (ARE) were treated surgically. The most frequently involved roots were L5 and S1, and the commonest anomaly observed was fusion of adjacent roots. The malformations were either bilateral, symmetric or asymmetric, their preoperative diagnosis being by radiculography with metrizamide. Diagnostic criteria and limitations relating to the different varieties of ARE are discussed, confirmation of the presence of the anomaly depending on two peroperative findings. Conventional operative techniques involve wide surgical exploration, but pediculectomy supplies a new approach to the problem, and the advantages of a microsurgical technique are discussed. Improved results can be expected in the future following preoperative recognition of the presence of ARE and advances in operative techniques.