[Early diagnosis of bacterial brain abscesses: interest of diffusion-weighted MRI]. / Diagnostic précoce des abcès cérébraux bactériens: intérêt de l'IRM en séquences de diffusion.

Three cases of bacterial brain abscesses, in immunocompetent patients, are reported. In all these cases, the diffusion-weighted magnetic resonance (MRI) with apparent diffusion coefficient (ADC) map has permitted an early diagnosis and a rapid treatment. This emergency MRI showed in the three cases a low signal on TI-weighted images, a high signal on T2-weighted and echo-planar images, and a decrease of ADC (0.36- 0.49 x 10(-3) mm2/s). So, this new MRI technique provides an available and rapid element in the brain abscess diagnosis which often remains a complex clinical and radiological diagnosis.

Chiari I malformation: a rare cause of noncommunicating hydrocephalus treated by third ventriculostomy.

OBJECT: Hydrocephalus associated with Chiari I malformation is a rare entity related to an obstruction in the flow of cerebrospinal fluid (CSF) in the foramen of Magendie. Like all forms of noncommunicating hydrocephalus. it can be treated by endoscopic third ventriculostomy (ETV). The object of this study is to report a series of five cases of hydrocephalus associated with Chiari I malformation and to evaluate the use of ETV in the treatment of this anomaly. METHODS: Five patients (four women and one man with a mean age of 29.6 years) underwent ETV for hydrocephalus associated with Chiari I malformation between April 1991 and February 1997. All patients had presented with paroxysmal headaches, which in two cases were associated with visual disorders. All patients had also presented with hydrocephalus (mean transverse diameter of the third ventricle 12.79 mm; mean sagittal diameter of the fourth ventricle 18.27 mm) with a mean herniation of the cerebellar tonsils at 13.75 mm below the basion-opisthion line. Surgery was performed in all patients by using a rigid endoscope. No complications occurred either during or after the procedure, except in one patient who experienced a wound infection that was treated by antibiotic medications. The mean duration of follow up in this study was 50.39 months. Four patients became completely asymptomatic and remained stable throughout the follow-up period. One patient required an additional third ventriculostomy after I year, due to secondary closure, and has remained stable since that time. Postoperative magnetic resonance images demonstrated a significant reduction in the extent of hydrocephalus in all patients (mean transverse diameter of the third ventricle 6.9 mm [p = 0.0035]; mean sagittal diameter of the fourth ventricle 10.32 mm [p = 0.007]), with a mean ascent of the cerebellar tonsils from 13.75 mm below the basion-opisthion line to 7.76 mm below it (p = 0.01). In addition, CSF flow was identified on either side of the orifice of the third ventriculostomy in all patients postoperatively. CONCLUSIONS: Results in this series confirm the efficacy of ETV in the treatment of hydrocephalus associated with Chiari I malformation. It is a reliable, minimally invasive technique that also provides a better understanding of the pathophysiology of this malformation.

[Belated diagnosis of medullar compression in a case of post-polio syndrome]. / Découverte tardive dune compression médullaire à loccasion de la prise en charge dun syndrome post-polio.

The physiatrist observes about his practice individuals with sequela of old poliomyelitics. A part of them have unusual fatigue and muscular pains and weakness. The hypothesis of an evolution of neuro-biological mechanism suggested by few authors isn't, actually, demonstrated. More probably, the modifications of lesional and, functional changes with disability observed are the consequence of elderly effects and decreasing of physical activites. We report a case of spinal cord compression by intramedullar tumor, associated with a post-polio syndrome.

[Pathologic vascular malformations of the spinal cord]. / Pathologie vasculaire malformative de la moelle épinière.

Like for the intracranial level, spinal cord vascular malformations can be classified, according to their radiological (particularly arteriographic) and histological aspects, as: arteriovenous malformations, cavernomas and so-called malformations, arterial aneurysms, and venous malformations. This classification should also include the involvement of the surrounding envelopes. Clinical manifestations are not always typical. Magnetic resonance imaging is useful for diagnosis, and angiography is not always necessary nowadays. Arteriovenous malformations are the most frequent vascular malformations; they are equally represented by arteriovenous fistulas of the dura mater and intradural arteriovenous malformations. Intradural cavernomas are rare as compared to arteriovenous malformations. Intradural arterial aneurysms are a rare, owing to local haemodynamic conditions. Venous malformations are exceptional; some intramedullar forms have been recently reported.

[Head injuries in the acute phase]. / Les traumatismes crâniens à la période aiguë.

Half of patients with traumatic head injuries are comatose (Glasgow coma scale < or = 8); motor vehicle accidents among young people are the predominant mode of injury. CT scanner reveals a large variety of lesions such as extracerebral hematomas, focal or diffuse hematomas, deep lesions. Surgery is performed in one quarter of these patients and indications are extracerebral hematomas, depressed fracture or craniofacial wounds. Indications for surgery in focal intracerebral lesions are difficult and depend on patient age, evolutivity and delayed intracranial hypertension; shift on CT scanner and compression of basal cisterns are the predictors of developing intracranial hypertension. Medical treatment depends on patient severity state; with comatose patient, intensive care unit is required with intubation, ventilation and intracranial pressure measurement by ventricular drain. If the pressure is greater than 20 mmHg, barbiturate therapy is indicated.

Idiopathic spinal cord herniation: value of MR phase-contrast imaging.

We report two patients with an idiopathic transdural spinal cord herniation at the thoracic level. Phase-contrast MR imaging was helpful in showing an absence of CSF flow ventral to the herniated cord and a normal CSF flow pattern dorsal to the cord, which excluded a compressive posterior arachnoid cyst.

Endoscopic management of colloid cysts.

OBJECTIVE: Several surgical approaches have been proposed for the treatment of colloid cysts, which still remains controversial. The most recent technique used is endoscopy. By its nature, endoscopy cannot offer complete removal, as compared to microsurgical techniques, but can do more than puncture. To evaluate the usefulness of endoscopy for colloid cyst surgery, a series of 15 patients who were operated on for colloid cysts under endoscopic control since 1994 was reviewed. METHODS: The presenting symptoms of our patients (10 men and 5 women) were intermittent headache (10 patients), nausea (3 patients), short-term memory loss (4 patients), coma (2 patients), gait disturbance (3 patients), blurred vision (2 patients), and mental status changes (3 patients). The sizes of the cysts ranged from 4 to 50 mm (median, 22.93 mm). Depending on the radiological appearance, the procedure was performed via a right (10 patients) or left (5 patients) precoronal burr hole. A rigid neuroendoscope was used. Initial stereotactic placement of the neuroendoscope was used in two patients who had moderate hydrocephalus. In the other patients, hand-guided endoscopy was performed using an articulated arm. The cysts were perforated with a needle. The opening was enlarged with microscissors. The cyst material was aspirated, and the remaining capsule was coagulated. RESULTS: The average follow-up was 15.26 months (range, 1-28 mo). Total aspiration of the cysts was achieved in 12 patients, as revealed by normal postoperative magnetic resonance imaging. Control magnetic resonance imaging revealed residual cysts in three patients. One patient presented with an asymptomatic recurrence at 1 year. Resolution of the symptoms was obtained in all patients except for two of the four patients with preoperative memory deficit (improvement without complete recovery). There was no mortality or morbidity. CONCLUSION: These results show that endoscopy is a safe and promising percutaneous technique for the treatment of colloid cysts of the third ventricle. Longer follow-up is, however, still required.

Percutaneous endoscopic treatment of suprasellar arachnoid cysts: ventriculocystostomy or ventriculocystocisternostomy? Technical note.

The use of an endoscope in the treatment of suprasellar arachnoid cysts provides an opening of the upper and lower cyst walls, thereby allowing the surgeon to perform a ventriculocystostomy (VC) or a ventriculocystocisternostomy (VCC). To discover which procedure is appropriate, magnetic resonance (MR)-imaged cerebrospinal fluid (CSF) flow dynamics in two patients were analyzed, one having undergone a VC and the other a VCC using a rigid endoscope. Magnetic resonance imaging studies were performed before and after treatment, with long-term follow-up periods (18 months and 2 years). The two patients were reoperated on during the follow-up period because of slight headache recurrence in one case and MR-imaged CSF flow dynamics modifications in the other. In each case surgery confirmed the CSF flow dynamics modifications appearing on MR imaging. In both cases, long-term MR imaging follow-up studies showed a secondary closing of the upper wall orifice. After VCC, however, the lower communication between the cyst and the cisterns remained functional. The secondary closure of the upper orifice may be explained as follows: when opened, the upper wall becomes unnecessary and tends to return to a normal shape, leading to a secondary closure. The patent sylvian aqueduct aids the phenomenon, as observed after ventriculostomy when the aqueduct is secondarily functional. The simplicity of the VCC performed using endoscopic control, which is the only procedure to allow the opening in the cyst's lower wall to remain patent, leads the authors to advocate this technique in the treatment of suprasellar arachnoid cysts.

[Intra-extracranial meningioma in the cranial vault]. / Les méningiomes intra-extracrâniens de la voûte.

Between 1982 and 1993, 11 cases of intra-extracranial vault meningiomas were treated in Créteil, by the same multidisciplinary team. The average age was 53.5 years and the Karnofsky rating was high (> 80 in 7 cases). Ten of the 11 cases had medial tumours with venous sinus thrombosis occurring in 9 of these. The location of the tumour was frontal in 6 and parietal in 4 patients. Of the medial tumours, 5 (half) were bilateral intracranial lesions. The average duration of symptoms was more than 10 years in four cases, between 1 and 3 years in five, and the diagnosis was made immediately in two patients. MRI coronal sections, after venous contrast injection, allowed diagnosis of the lesion and visualisation of the sinus thrombosis. Embolisation was performed pre-operatively in all cases scheduled to have surgery, resulting in safe excision of the tumour. Surgery was performed in 9 patients with complete tumour removal achieved in 8. Of those who did not undergo surgery, one received radiotherapy and the other died before treatment. The bony defect was covered with cadaveric bone, autogenous bone, coral and methyl-methacrylate in one, two, two and two patients respectively. Complications occurred in 2 cases: extradural secondary infection and CSF rhinorrhea treated with a lumbo-peritoneal shunt. The post-operative Karnofsky rating was greater than 90 in seven cases, 70 in one, and 50 in two cases. After an average follow-up of 4 years, 3 patients had tumor recurrence at 4, 7, and 8 years; the first having a locally malignant character, the second showing radiological recurrence in a case of subtotal removal, and the third a marginal recurrence. Two of the 3 patients underwent further surgery. The malignant case, received radiotherapy but unfortunately a new recurrence occurred 14 months later. As radiotherapy was used in only 3 cases, statistically significant conclusions concerning efficacy cannot be drawn.

[Antibiotic prophylaxis in neurosurgery]. / Antibioprophylaxie en neurochirurgie.

Postoperative wound infections are a serious complication in neurosurgery. The average infection rate without antibiotics ranges between 5-11% in CSF shunts, between 2-5% in craniotomies and spinal surgery in clean and clean contaminated patients, and 11-38% in CSF fistulas. In CSF shunt procedures as well as in craniotomies, common skin commensals, mainly coagulase negative and positive staphylococci are responsible for most postoperative infections. Contradictory results of the studies evaluating the efficacy of prophylactic antibiotics (PA) make it impossible to conclude whether antibiotics have any impact on the incidence of infections or not. Nevertheless the decision to use PA must be left to each surgeon and based on own experience (the mean rate of infection decreased from 5-11% to 1% with PA in France). In clean and clean contaminated surgery, the weight of evidence based on some large, prospective, randomized studies, suggests that PA exerts a protective effect, for which an antistaphylococci antibiotic would be appropriate. In case of methi-R organisms, a second generation cephalosporin is an alternative. Association of vancomycin-gentamicin is not recommended routinely because of the risk of development of resistance.

[Neuro-aggressive dorsal vertebral hemangioma and vertebrectomy. Apropos of 2 cases. Review of the literature]. / Hémangiome vertébral dorsal neuro-agressif et vertébrectomie. A propos de 2 cas. Revue de la littérature.

PURPOSE OF STUDY: Vertebral hemangioma is a benign and relatively frequent lesion. It is rarely associated with medullary compression. Two cases of vertebral hemangioma with progressive neurologic deficit are presented. METHODS AND RESULTS: Successful treatment was accomplished using pre-operative embolization and vertebrectomy. The tumor was resected by an antero-lateral transthoracic and posterior approach. DISCUSSION: The technique of operative management and complications are discussed. Based on these two patients and a review of the literature, the authors recommend that management of patients with progressive neurological deficit should include pre-operative angiography and embolization, decompressive surgery with the approach determined by the degree of vertebral involvement and site of spinal compression.

[Neurosurgical endoscopy. Diagnostic and therapeutic indications]. / L'endoscopie neurochirurgicale. Indications diagnostiques et thérapeutiques.

An historical review of neurosurgical endoscopy is evocated. The characteristics of the endoscopic material are discussed: flexible or rigid?, length?, diameter?, irrigation?, free-hand manipulation or fixed arm? A rigid neurosurgical endoscope (STORZ) is described which characteristics are the following: 5 mm/3.7 mm ovale diameter, working length of 21 cm (allowing its use under stereotactic conditions), 5F working channel and articulated arm for solid immobilization in the desired position. All the indications of endoscopy are described and illustrated with a series of 48 patients. Indications for diagnosis are rare and summarised in exceptional help for conventional surgery. 80% of the usual indications of endoscopy were represented by third ventriculostomy. The endoscopic guidance brings safety and allows an increasing of the ventriculostomy's indications. Endoscopic fenestrations of arachnoid cyst are described with a particular interest on suprasellar cysts. The other indications are rare: unilateral hydrocephalus, biopsies of intraventricular tumors, puncture of colloid cysts.

Multiple vertebral hemangiomas with neurological signs. Case report.

A case of multiple vertebral hemangiomas with progressive neurological deficit is presented. Successful treatment was accomplished using preoperative embolization, palliative surgical decompression, and postoperative radiation therapy. The patient has remained asymptomatic for 6 years. The authors review the role of current imaging modalities and options for therapeutic intervention. Preoperative embolization, palliative surgical decompression, and postoperative radiotherapy appear to provide a satisfactory outcome in patients with multiple hemangiomas and may represent an effective alternative to more aggressive surgical intervention.

[Pseudo-oligodendrogliomatous meningioma. Report of 2 cases and review of the literature]. / Méningiome pseudo-oligodendrogliomateux. Etude de deux cas et revue de la littérature.

We report two cases of oligodendroglioma-like meningioma revealed by symptoms of increased intracranial pressure, progressive hemiparesia and partial epileptic seizures. Brain CT-scan or scintigraphy and carotid arteriography were suggestive of a convexity meningioma. One patient had received radiation treatment for scalp tinea capitis 25 years previously. In spite of complete surgical removal, the tumor recurred in both cases respectively 17 years and 18 months later. The two patients were operated again, and one underwent a complementary radiotherapy. Pathologic diagnosis was particularly difficult in the first case where the pattern at conventional histologic technics was that of oligodendroglioma. On the occasion of recurrence, immuno-histochemistry and ultrastructural studies were performed. The tumor was positive for epithelial membrane antigen (E.M.A) and cytokeratin, but was negative for glial fibrillary acidic (G.F.A.) protein, S 100 protein (S 100), neuron-specific enolase (N.S.E.), vimentin, anti-LEU-7 (N.H.K.1), and neurofilaments (N.F.). Electron microscopy showed closely adjacent cells with tonofilaments and numerous desmosomes. These findings permitted to establish the diagnosis of oligodendroglioma-like meningioma instead of oligodendroglioma. In the second case, the histologic pattern was also reminiscent of oligodendroglioma, but presence of few cellular whorls in some part of the tumor permitted the correct diagnosis. The pathogenesis of this atypical form of meningioma, its tendency for recurrence, and usefulness of radiotherapy are discussed and literature is reviewed.

Giant gangliocytic paraganglioma of the filum terminale. Case report.

The clinical and pathological features of a giant cauda equina paraganglioma arising from the intradural filum terminale is described. Scattered mature large neurons characterized the tumor as a gangliocytic paraganglioma. Histologically, these neoplasms have considerable similarity with ependymoma and the diagnosis can be easily missed unless special techniques are employed.

Sacral lipoma of the filum terminale with dural arteriovenous fistula. Case report.

A patient presenting with progressive paraparesis was found to have a dural sacral arteriovenous (AV) fistula. His condition deteriorated abruptly after thoracolumbar angiography. Embolization of the fistula improved the patient's status so that he was able to walk with crutches. One year later his neurological condition worsened. He was treated via an enlarged laminectomy because of uncertainty concerning a lipoma noted on the initial computerized tomography scan. The lesion consisted of an intradural filum terminale lipoma associated with an AV fistula, both of which were excised. The patient's condition was unchanged 6 months later. The different types of spinal lipomas and spinal AV malformations are reviewed, and mechanisms are proposed to explain the clinical deterioration in this patient. Venous hypertension seems to be the most likely possibility. The lipoma may have produced local hypervascularization of the dura mater with a subsequently acquired AV fistula.

[The role of surgery and low molecular weight heparin in the treatment of cerebral venous thrombosis. Apropos of 2 cases]. / Place de la chirurgie et des héparines de bas poids moléculaire dans le traitement des thromboses veineuses cérébrales. A propos de 2 cas.

For one case of thrombosis of sinus sagittalis superior joint haemorrhagic cerebral softening necessitates surgical draining of haemorrhagic focus grown to a true intracranial haematoma; for the another case direct low molecular weight heparin treatment obtained a mere evolution. Authors are of the opinion that early low molecular weight heparin treatment is able to avoid massive haemorrhage.

[Vertebral hemangioma with neurologic signs. Clinical presentation, results of a survey by the French Society of Neurosurgery]. / Hémangiomes vertébraux avec signes neurologiques. Le contexte clinique, résultats de l'enquête de la S.F.N.

45 cases of vertebral hemangiomas with neurologic involvement are reported. This series corresponds to the french experience between 1969 and 1988 (series of the "Société Française de Neurochirurgie" (S.F.N.)). In this report the clinical presentation and the results of the radiological examination are detailed. Local vertebral pain was present in half of the cases. The neurological symptoms were related to spinal cord compression in 33/45 of the patients and to radicular suffering in the other cases. Evolution of the neurological symptoms appeared to be slow: the mean evolution time before diagnosis was of 10 months. Hemangioma involved the thoracic column in 73% of the cases. Neurologic symptoms was due to a diffuse narrowing of the spinal canal in 28.8% of the cases, to a local bony expansion in 60% of the cases. Hemangioma was found to involve the whole vertebra in 44.4% of the cases, the vertebral body alone in 24.4% of the cases and the posterior arch alone in 22.2% of the cases. An incomplete involvement of both vertebral body and posterior arch was found in 6.6% of the cases. 2.2% of the cases corresponded to pure epidural hemangioma. Preoperative diagnosis was established in 58% of the patients. In these cases, the diagnosis was based on standard radiography and CT datas. Results of the S.F.N. serie are compared with those of the main series of the literature.

[Vertebral hemangioma with neurologic signs. Therapeutic results. Survey of the French Society of Neurosurgery]. / Hémangiomes vertébraux avec signes neurologiques. Les résultats thérapeutiques. Enquête de la S.N.F.

45 cases of vertebral hemangiomas with neurologic involvement are reported. This series corresponds to the french experience between 1969 to 1988 (series of the "Société Française de Neuro-Chirurgie" (S.F.N.)). In this report, the therapeutic results are detailed. 16 patients were treated by a simple laminectomy, 6 by laminectomy associated with radiotherapy, 4 by radiotherapy alone. In 9 patients, a large removal of the hemangioma was performed by mean of a lamino-arthrectomy (7 cases) or a corporectomy (2 cases). 7 patients were treated by embolization or vertebroplasty. Both techniques were used alone or in association with surgery or radiotherapy. 3 patients had no therapy. Results of the S.F.N. series demonstrated that 75.5% of the patients had a long term favorable clinical course. 13.4% of the patients were not improved. Mortality was of 11.1%. The mean follow up time was of 51.6 months. Recurrence was encountered in 13 cases. It was mainly observed in the first two years. In cases of total involvement of the vertebrae by hemangioma, laminectomy associated with radiotherapy was the best mean of therapy: 93% of recovery without recurrence. Treatment of body localization appeared to be difficult. Corporectomy could be unefficient if a complete removal of the hemangioma could not be performed. In contrast, posterior arch localization was successfully treated by a simple laminectomy without radiotherapy, even in cases of incomplete removal of the hemangioma: all such cases (10 cases) had a complete recovery without recurrence.