Comparative study of the posterior red nucleus in baboons and gibbons.

The posterior red nucleus (PRN) was studied in two species of primates by the technique of retrograde degeneration of rubrospinal cells following transection of the spinal cord at different levels. The form of the PRN was reconstructed for both a quadruped monkey (baboon) and an anthropoid with erect posture (gibbon). The PRN contains polymorphic cells characterized by their very chromophilic and granular Nissl substance. These neurons vary in diameter from 25 micrometer to 70 micrometer. Some of them give rise to the rubrospinal tract. Baboon: The approximately 1,300 rubrospinal cells in this species are divided into two equal groups, one related to the contralateral forelimb, with axons ending between the second cervical and third thoracic segment, and the other related to the contralateral hindlimb, projecting caudally beyond T3. Following a high cervical lesion, nondegenerated cells of similar description remain throughout the nucleus. A significantly large group of these cells occurs medially and may be the source of fibers ending in the brain stem or cerebellum. Gibbon: In this species, the number of rubrospinal cells controlling the hindlimb is less than half that found in the baboon. This reduction in the gibbon is much greater for medium-sized cells, but is also significant for the giant cells. These results obtained from primates are compared with those reported for the cat. A possible function for the PRN in the control of limb movements is discussed from the viewpoint of phylogeny.

Correlation between cytogenetic and histopathological findings in 75 human meningiomas.

The correlations between cytogenetic and histopathological findings were analyzed in 75 human meningiomas. The tumors were classified according to increasing degrees of anaplasia into three grades: Grade I, benign; Grade II, atypical; Grade III, anaplastic. In 45 tumors of Grade I (benign), we more often observed a normal karyotype or monosomy 22. In 23 tumors of Grade II (atypical), we observed karyotypes with structural and/or numerical abnormalities with the presence of telomeric associations in 8 of them. These last tumors were fibroblastic. In seven Grade III tumors (anaplastic), we also observed complex abnormalities, and in one case, we observed telomeric associations. Our observations show that complex chromosome abnormalities and telomeric associations are observed in tumors that histologically display a certain degree of anaplasia. It is possible that the result of histopathological and cytogenetic correlations might represent a prognostic factor in meningiomas.

Hemangiopericytomas of the spinal canal. Report of four cases and review of literature.

The Authors report four cases of spinal hemangiopericytomas. The diagnosis has been ascertained by electron microscopy. Despite the malignant nature, the association of surgery and radiotherapy is interesting in that it prolongs the survival rate. Clinical, neuroradiological, microscopic and ultrastructural features of intraspinal hemangiopericytomas are evaluated in the light of the review of the relevant literature.

Long-term results of conventional surgical treatment for epilepsy. Delayed recurrence after a period of 10 years.

The results of the surgical treatment of epilepsy were studied in 44 patients 10 or more years after operation. Thirty-seven patients underwent operation only once; these patients were observed 11-26 years postoperatively. Seven patients had a recurrence within 5 years after operation and required a second operation; these patients were observed 11-17 years after the second operation. Recovery persisted for 15-27 years in 32 patients. There was a recurrence in 12 cases 11-19 years after operation. With one exception, these recurrences were satisfactorily treated medically.

[Ultrastructural study of a Masson's "humid meningioma"]. / Etude ultrastructurale d'un "méningiome humide" de Masson

The authors report the ultrastructural analysis of a Masson's humic meningioma. The tumor presents at the electronic microscopic examination every sign of secretive hyperactivity and does not show any degenerative characteristics. The existence of an important extracellular material rich in pre-collagenic fibres accounts for lacunar texture of this neoplasia at optic microscopic investigation; the role played by tumoral cells in the elaboration of the material is taken into account and seems to corroborate histogenic ecto-mesenchymatous theory of arachnoidal cells.

[Treatment of choroid melanoma by Gamma-Knife radiosurgery]. / Traitement du mélanome choroïdien par radiochirurgie Gamma-Knife.

Conservative treatment of uveal melanomas by Gamma Knife Radiosurgery is based on the use of cross fire technique with 201 Cobalt60 sources. A following of 13 months is available for the first case operated by Gamma-Knife Surgery in France. Technical baselines and one year preliminary results are reported. The diagnosis of uveal melanoma T3NOMO was established by converging results of clinical examination, angiography and echography. The definition of the target was based on stereotactic MRT examination. We delivered a dose of 50 Gys to the marginal isodose (50%). Today, one year after treatment the tumor decreased, the visual function was preserved. There were no side effect or complication.

[Nociceptive flexion reflex of the leg. Use after surgical treatment of herniated disk]. / Réflexe nociceptif de flexion de la jambe. Utilisation après intervention chirurgicale pour hernie discale.

In patients suffering from acute sciatica due to herniated disk Lasegue's manoeuvre inhibits the leg flexion nociceptive reflex (RIII reflex) in either the ipsilateral or the contralateral limb. This is thought to be due what is called "diffuse noxious inhibitor control" modulating the activity of a group of convergent spinal neurons. The purpose of this study was to determine whether surgical resection of the herniated disk in patients suffering from sciatica might relieve this so-called "counter-irritation". Among 10 patients whose sciatica resulted from herniated disk, the decrease in amplitude of the RIII response observed when Lasegue's manoeuvre is applied disappeared in 7 patients, 6 to 8 days after surgical resection of the herniated disk. These results suggest that this test might be a useful tool for postoperative prediction of radicular compression.

[Stereotaxic guidance in open surgery of the brain]. / Guidage stéréotaxique de certaines interventions à crâne ouvert.

The authors describe the technique used to precisely locate, before surgical ablation, small superficial or deep seated intracerebral lesions. When they are superficial, a burrhole is placed above the lesional site, that is reconstructed by superimposing the CT image onto a plain film radiogram taken during stereotaxy. Deep seated lesions are localized by inserting a guide under stereotaxy, prior to open surgery, which will lead the neurosurgeon without error from the cortex to the lesion. 37 observations are reported where this technique lead to a greatly simplified intervention with minimal cortical damage.

[Prevention of risk in stereotaxic biopsy of various tumors of the pineal region. Apropos of 3 cases]. / De la prévention des risques de la biopsie stéréotaxique de certaines tumeurs de la région pinéale. A propos de 3 observations.

During the last ten years, the authors have performed 750 stereotactic biopsies with 6 deaths. In 3 cases, the lesion was a pinealoblastoma, with comparable symptomatology and CT scan image. Safety measures are discussed.

[Modern imaging and stereotaxy]. / Imagerie moderne et stéréotaxie.

The authors present their technique of utilization in stereotaxic neurosurgery of CT and IRM documents realized in standard condition. Besides, they present an original apparatus that allows to combine the advantages of Leksell and Talairach's stereotaxic system.

[The role of stereotaxic biopsy in the therapeutic approach to malignant gliomas (author's transl)]. / Place de la biopsie en condition stéréotaxique dans la tactique thérapeutique des gliomes malins.

Analysis of 770 biopsies of intra-cerebral neoplasms under stereotaxic conditions and performed in Bordeaux, Rennes and Marseilles. The study emphasized the relative benign nature of this examination (1% deaths, 1.4 % severe sequellae) bearing in mind the severity of the underlying disease. In a very large number of cases (from 7 to 38% according to Schools) the diagnosis made before biopsy was fundamentally altered by this examination. The quasi-certitude of the nature of the lesion, and the possible facilitation of surgery by the precision of the lesional topography, and finally the possibility of a therapeutic gesture of evacuation in certain cases, is felt to justify intra-cranial biopsy performed under stereotaxic conditions.

[Role of transcutaneous electric stimulation in indication for implantation of an analgesic stimulator]. / Place de la stimulation electrique cutanée dans l'indication d'implantation d'un stimulateur analgésique

UNLABELLED: The author's describe: I. METHODS OF ANALGESIC CUTANEOUS STIMULATION: I) Transcutaneous analgesic stimulation: Stimulations realized by biphasic asymetrical "waves" of 0 to 80 milliamps intensity for a frequency of 10 to 100 cycles/S. -Place of the stimulation: a painful area. -Stimulation length: 15 to 20 minutes, repeated during several days. RESULTS: appreciate patients tolerance to the tingling sensation. Test the analgesic effect, sometimes sufficient to treat the patient. 2) Analgesic percutaneous stimulation: The percutaneous electrode is applicated to the dura, without penetrating it. Same types of results as for transcuteneous stimulation but more precise. II. DEFINITION of the indication of chronic implantation of an analgesic stimulator. Studying results of repeated analgesic transcutaneous stimulations allows to distinguish between several possibilities. I) Intolerance of the sensation of stimulation: Contra-Indication or increasing of the pain. 2) Complete and lasting amelioration leads to: Chronic transcutaneous neurostimulation. 3) Partial amelioration, No amelioration leads to: Acute percutaneous stimulation either successful results after stimulation, : Chronic implantation: -of peripheral nerve -on a peripheric nerve -of dorsal column -on dorsal column, either paraesthesis without Analgesia:? III - EXPERIMENTAL APPROACH TO THE MECHANISM OF ACTION OF THE "ANALGESIANT" ELECTRIC STIMULATION. A cutaneous "analgesiant" stimulation produces, in the cat, the inhibition of evocated potential in C.M. by "nociceptive" stimulation of the sciatic nerve. The inhibition only appears after a 30 minutes latence. This let suppose different mechanisms from the "Gate Control" theory. The authors specify their personal results (Tab. 2.)

[Results of percutaneous selective thermocoagulation of Gasser's ganglion in essential facial neuralgia. Synthesis of results obtained in 939 treated patients]. / Résultats de la thermo-coagulation percutanée sélective du ganglion de Gasser dans la névralgie faciale essentielle. Synthèse des résultats obtenus chez 939 patients traités.

The authors report the late results of thermocoagulation of the gasserian ganglion in 939 patients operated by 3 different neurosurgical teams, (Bologna, Bordeaux, Marseille). It has been assessed that the results are comparable among the 3 teams and that percutaneous selective thermocoagulation represents a simple and low-risk technique with a high rate of efficacity.

[Long term results of electric stimulation of the conus medullaris in a case of neurogenic bladder]. / Résultats éloignés de la stimulation électrique du cône médullaire, en cas de vessies neurologiques.

The authors present long term results (19 to 45 months: Average 37 months) of electrical stimulation of the conus medullaris in neurologic bladder. In 3 cases, the result remain excellent: efficient stimulation, normal micturition, absence of residual urine. In 6 cases, after a long period of normal function, the micturition is poor with residual urine, eventhough the conus medullaris stimulation always produces a satisfactory contraction of the detrusor. In four cases the relapse is due to disease of the external sphincter region, poorly or untreated. In female patients the results are better than in male patients, with positive results in 2 of the 3 women and 1 of the 6 men. The authors find that their results can be compared with those of B. NASCHOLD, originator of the method. They emphasize the necessity of a close collaboration with the urologist to maintain excellent results.