[Can myelopathies secondary to arterio-venous dural fistulae be aggravated by intravenous corticosteroid therapy?]. / Les myélopathies secondaires aux fistules durales artério-veineuses peuvent-elles être aggravées par la corticothérapie intraveineuse?

Dural fistulas are the most common vascular malformations of the spinal cord. They are of unknown origin but constitute a recognized cause of myelopathy. Aggravation of the clinical manifestations, either spontaneously or after invasive procedures, has been described. We report the case of a patient with a four-month history of myelopathic syndrome involving the lower limbs. Intravenous corticosteroid steroid treatment (1g) given for a suspected inflammatory disorder, induced a dramatic flare-up of the neurological symptoms which were reversible within 48 hours after corticosteroid withdrawal. The causal effect of the steroid treatment is discussed.

[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.

A new device for endoscopic third ventriculostomy.

Since its description by Dandy in 1922, several techniques have been used to perform third ventriculostomy under endoscopic control. Except for the blunt technique, in which the endoscope is used by itself to create the opening in the floor of the third ventricle, the other techniques require more than one instrument to perforate the floor of the ventricle and enlarge the ventriculostomy. The new device described is a sterilizable modified forceps that allows both the opening of the floor and the enlargement of the ventriculostomy in a simple and effective way. The new device has the following characteristics: 1) the tip of the forceps is thin enough to allow the easy perforation of the floor of the ventricle; 2) the inner surface of the jaws is smooth to avoid catching vessels of the basal cistern; and 3) the outer surface of the jaws has indentations that catch the edges of the opening to prevent them from slipping along the instrument's jaws. The ventricle floor is opened by gentle pressure of the forceps, which is slowly opened so that the edges of the aperture are caught by the distal outer indentation of the jaws, leading to an approximately 4-mm opening of the floor. This device has been used successfully in 10 consecutive patients. This new device allows surgeons to perform third ventriculostomy under endoscopic control in a very simple, quick, and effective way, avoiding the need for additional single-use instruments.

[Endoscopic anatomy of the third ventricle]. / Anatomie endoscopique du troisieme ventricule.

According to the development of neurosurgical endoscopy (and especially for third ventriculostomy), the endoscopic anatomy in hydrocephalus should be well known and utilized for orientation. The endoscopic pictures are obtained with a 30; telescope, acquired by a digitalized camera and visualized on a video monitor. The pictures are then numerized on a DKR system. Endoscopic anatomy of the third ventricle is described with a particular focus on the anatomical landmarks and their variations around the foramen of Monro, the anterior and posterior walls of the third ventricle. The knowledge of this anatomy is essential for the safety and the reliability of intraventricular endoscopic procedures.

[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.

[Normal pressure hydrocephalus in an elderly patient]. / Hydrocéphalie à pression normale chez le sujet âgé.

INTRODUCTION: Idiopathic normal pressure hydrocephalus is a disease that most frequently concerns subjects of an advanced age. It is not easy to establish a definitive diagnosis, and the practitioner frequently encounters decision-making problems regarding the following question: should a shunt be performed, or not? Opinions remain contradictory, even though the available scientific data is increasingly precise. The aim of this review is to analyze the physiopathogenic, clinical, paraclinical and therapeutic data associated with this type of hydrocephalus. CURRENT KNOWLEDGE AND KEY POINTS: If the clinical triad is determinant, no other investigation is in fact necessary to confirm the diagnosis, although it should always be questioned in the case of ventricular enlargement determined by tomodensitometry. The decision to perform the only efficient procedure, i.e., a ventricular shunt operation, depends upon a number of established arguments in favor of that procedure. Clinical improvement, which is often spectacular, can then confirm the diagnosis. FUTURE PROSPECTS AND PROJECTS: The efficacy of surgical treatment has been confirmed by clinical studies, and there is a reduced tendency as regards post-operative complications. However, each case should be considered individually and with the cooperation of and coordination between the family, the physician and the neurosurgeon.

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.

Peripheral selective neurotomy of the brachial plexus collateral branches for treatment of the spastic shoulder: anatomical study and clinical results in five patients.

A new type of peripheral selective neurotomy involving the collateral branches of the brachial plexus has been perfected for treatment of the spastic shoulder. Anatomical study of six cadaveric shoulders led to the specification of a surgical approach to the pectoralis major and teres major nerves, which innervate the main muscles implicated in shoulder spasticity. Between August 1994 and September 1995, five patients (four men and one woman) underwent two to four associated neurotomies of the upper limb, which included neurotomies of the pectoralis major (all five patients) and the teres major (two patients). The average follow-up period was 11 months, during which there were no local or general complications. The spasticity of the treated muscles resolved in all five patients (Held score range 3-0). The neurotomies led to statistically significant average amplitude increases in shoulder mobility, especially in abduction (+30 degrees), antepulsion (+50 degrees), retropulsion (+20 degrees), and external rotation (+20 degrees). The functionally useful active amplitude scores increased from 2.66 to 5.16/6. This functional improvements mainly involved the standing position and walking stability, as well as improvement in the range of motion of the lower limb. These results encourage the increasing use of this new type of neurotomy in treatment of the spastic upper limb.

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.

A common bronchial arterial trunk arising from a left subclavian artery: a rare anatomic variant.

The origin of the bronchial arteries is very variable. An exceptional case is reported of a common bronchial arterial trunk arising from a left subclavian artery discovered incidentally during angiography in a patient without any pulmonary disease. An embryologic explanation is proposed for this anatomic variant.

[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.

[Prevention of wound infections in neurosurgery]. / La prévention du risque infectieux du site opératoire en neurochirurgie.

Post-operative wound infections are a serious complication in neurosurgery. The average wound infection without antibiotics ranges between 5-11% in C.S.F. shunts, 2-5% in clean and clean contaminated patients; 11-38% in C.S.F. fistula. In C.S.F. shunt procedures, common skin commensals are responsible for most post-operative infections, mainly coagulase negative and positive staphylococci. Contradictory results of the studies evaluating the efficacy of antibioprophylaxis make it impossible to conclude whether antibiotics have any impact on the incidence of infections. Neverless the decision to adopt antibioprophylaxis must be left to each surgeon and based on their own experience (mean level of infection dropped from 5-11% to 1% with ABP in France). In clean and clean contaminated patients, the weight of evidence based on some large, prospective, randomized studies, suggest that ABP exert a protective effect, for which an antistaphylocci antibiotic would be appropriate. In case of Methi-R organisms, a second generation cephalosporin is an alternative candidate. Association of Vancomycin-Gentamycin is not recommanded routinely because of the risk of development of resistance. In skull fracture and C.S.F. fistula, the results of studies does not favour the routine administration of antibiotics.