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Resume Un patient de 74 ans est adresse pour prise en charge de troubles de l’equilibre, associes a une paralysie du nerf oculomoteur commun et du nerf moteur oculaire externe droit, survenus dans les semaines suivant un traumatisme crânien sans perte de connaissance. Lors de la consultation, une paralysie du III et du VI controlateral (gauche) est notee, tandis que la motricite oculaire du cote droit est normale. Le reste de l’examen ophtalmologique est sans particularites. La reprise d’un interrogatoire detaille permet de mettre en evidence la presence d’acouphenes pulsatiles apparus dans les jours suivant le traumatisme et l’examen clinique retrouve un souffle systolique a l’auscultation de la region pre-tragienne. Le diagnostic de fistule durale bilaterale est confirme a l’arteriographie cerebrale. Les caracteristiques cliniques des fistules durales ou fistules indirectes, ainsi que les strategies therapeutiques proposees dans la litterature sont revues.

There is growing evidence that gravity markedly influences vertical eye position and movements. A new model for the organization of brainstem upgaze pathways is presented in this review. The crossing ventral tegmental tract (CVTT) could be the efferent tract of an "antigravitational" pathway terminating at the elevator muscle motoneurons in the third nerve nuclei and comprising, upstream, the superior vestibular nucleus and y-group, the flocculus, and the otoliths. This pathway functions in parallel to the medial longitudinal fasciculus pathways, which control vertical eye movements made to compensate for all vertical head movements and may also comprise the "gravitational" vestibular pathways, involved in the central reflection of the gravity effect. The CVTT could provide the upgaze system with the supplement of tonic activity required to counteract the gravity effect expressed in the gravitational pathway, being permanently modulated according to the static positions of the head (i.e., the instantaneous gravity vector) between a maximal activity in the upright position and a minimal activity in horizontal positions. Different types of arguments support this new model. The permanent influence of gravity on vertical eye position is strongly suggested by the vertical slow phases and nystagmus observed after rapid changes in hypo- or hypergravity. The chin-beating nystagmus, existing in normal subjects with their head in the upside-down position, suggests that gravity is not compensated for in the downgaze system. Upbeat nystagmus due to brainstem lesions, most likely affecting the CVTT circuitry, is improved when the head is in the horizontal position, suggesting that this circuitry is involved in the counteraction of gravity between the upright and horizontal positions of the head. In downbeat nystagmus due to floccular damage, in which a permanent hyperexcitation of the CVTT could exist, a marked influence of static positions of the head is also observed. Finally, the strongest argument supporting a marked role of gravity in vertical eye position is that the eye movement alterations observed in the main, typical physiological and pathological conditions are precisely those that would be expected from a direct effect of gravity on the eyeballs, with, moreover, no single alternative interpretation existing so far that could account for all these different types of findings.

Resume Un cas de nystagmus de convergence-retraction avec paralysie de la verticalite vers le haut et deviation oblique (hypotropie droite), sans autre manifestation neurologique, est rapporte. La lesion, probablement vasculaire, etait situee a la jonction meso-diencephalique, au carrefour entre le bord droit de la commissure posterieure, le noyau interstitiel de Cajal droit et la substance periaqueducale, expliquant les trois signes oculomoteurs. L’interet de ce cas tient particulierement au caractere tres limite de cette lesion.

Resume Nous rapportons le cas d’une patiente ayant presente une ophtalmoplegie complete compliquant un zona ophtalmique. La decouverte d’un meningiome temporal interne ipsilateral envahissant le sinus caverneux fait discuter l’origine tumorale ou infectieuse des signes ophtalmiques.

Comatose state is a major cause for admission to the intensive care unit. The most commonly used assessment score is the Glasgow coma scale (GCS). Although widely accepted, this score has several limitations. Recently, the full outline of unresponsiveness score (FOUR) has been validated and tested as reliable as the GCS.We translated this score in French and tested its reliability in a neurological critical care unit. This study included eight critical care patients and eight intensive care patients. The patients were successively evaluated by two neurologists, four experienced nurses and five inexperienced nurses; a total of 176 evaluations were performed. The weighted kappa (kappa(W)) was used to determine the reliability of the evaluation for both the FOUR score and the GCS.The mean age of the patients was 62 years. The interobserver reliability of the French version of the FOUR score was high (kappa(W)=0.86; IC 95%: 0.83-0.89) comparable to that of the GCS (kappa(W)=0.85; IC 95%: 0.82-0.88).The French version of the FOUR score has an excellent interobserver reliability. This score is easy to perform and well accepted, only requiring simple and short training.

Advances in our knowledge on eye movements over the last 25 years are reviewed, focusing on the author's experience. First, the advantages of binocular frontal vision, which is a common characteristic of all predator mammals, are compared to those of lateral vision, characterizing their preys. Binocular frontal vision implies a perfect parallelism of both eyes, which is ensured in the pons by means of the abducens nucleus, controlling abduction as well as adduction. The pathological example of the "one-and-a-half" syndrome, in which the abducens nucleus and the adjacent medial longitudinal fasciculus are simultaneously impaired, is described. The main brainstem syndromes involving vertical eye movements are also reviewed: in particular, the third nerve nucleus syndrome, in which both ipsilateral third nerve paralysis and contralateral superior rectus paralysis (with hypotropia) result from a unilateral third nerve nucleus lesion. A case of upbeat nystagmus (in the primary position of gaze) due to a small upper pontine lesion, probably affecting the ventral tegmental tract (VTT) is also reported. This is an opportunity to emphasize that, although a number of cases of upbeat nystagmus due to focal brainstem lesions affecting the upward vestibular pathway (UVP)--either at the upper pontine (VTT) or caudal medullary level--exist in the literature, no convincing cases with downbeat nystagmus (in the primary position of gaze) due to a focal brainstem lesion have been reported. Downbeat nystagmus could result from a UVP hyperactivity (secondary to a floccular lesion) and the notion that this pathway is physiologically predominant compared to the downward pathway, maybe due to gravity, is developed. A new hypothesis about the role of the caudal medulla in UVP is also proposed. Next, the cortical control of saccadic eye movements is reviewed, with a reminder that reflexive saccades are mainly triggered by the parietal eye field whereas intentional saccades depend upon the frontal eye field. The inhibition of reflexive saccades is mainly controlled by the dorsolateral frontal cortex (DLPFC), i.e. area 46 of Brodmann. A few examples of the use of saccades as a research tool and model in cognitive neurosciences are given. The use of memory-guided saccades allowed us to study spatial memory and led us to propose a relatively original conception of the cortical control of spatial memory in which the DLPFC, the parahippocampal cortex and the hippocampal formation could be involved successively according to specific periods of time. An experiment using functional magnetic resonance imaging in a paradigm studying decision is described, again with the involvement of the DLPFC in the decisional process. Lastly, the usefulness of eye movements in clinical neuro-ophthalmology at the bedside as well as in neurophysiological or even neuropsychological research in the laboratory is emphasized.

A case of convergence-retraction nystagmus with upward vertical gaze paralysis and skew deviation (right hypotropia), without any other neurological signs, is reported. The probably vascular lesion was located at the mesodiencephalic junction, lying between the right border of the posterior commissure, the right interstitial nucleus of Cajal and the periaqueductal grey matter, accounting for the three ocular motor signs. The particular interest of this case is due to the relative smallness of the lesion.

Balo's concentric sclerosis is a neuropathological type of multiple sclerosis characterized by alternating rings of spared myelin and demyelination. Diagnosis is based on MRI, but very few data are available concerning the lesion features using serial proton magnetic resonance spectroscopy (1H-MRS).We report 1H-MRS initial findings and disease course in one case of Balo's concentric sclerosis.The first 1H-MRS study of 2 concentric ring-enhanced lesions showed a decreased N-acetyl-aspartate (NAA) peak, an increased choline peak, 2 broad lactate peaks and the presence of a lipid peak at 0.9 ppm. Six months later, 1H-MRS showed a decrease of choline peak, whereas the lactate peak had disappeared. The NAA peak was still at a low level.These findings are similar to those reported in demyelinating disorders, such as multiple sclerosis. Thus, in Balo's concentric sclerosis, 1H-MRS may provide neurochemical arguments for inflammation and demyelination, and indicate the severity of axonal damage and recovery.

Our knowledge of the cortical control of saccadic eye movements (saccades) in humans has recently progressed mainly thanks to lesion and transcranial magnetic stimulation (TMS) studies, but also to functional imaging. It is now well-known that the frontal eye field is involved in the triggering of intentional saccades, the parietal eye field in that of reflexive saccades, the supplementary eye field (SEF) in the initiation of motor programs comprising saccades, the pre-SEF in learning of these programs, and the dorsolateral prefrontal cortex (DLPFC) in saccade inhibition, prediction and spatial working memory. Saccades may also be used as a convenient model of motricity to study general cognitive processes preparing movements, such as attention, spatial memory and motivation. Visuo-spatial attention appears to be controlled by a bilateral parieto-frontal network comprising different parts of the posterior parietal cortex and the frontal areas involved in saccade control, suggesting that visual attentional shifts and saccades are closely linked. Recently, our understanding of the cortical control of spatial memory has noticeably progressed by using the simple visuo-oculomotor model represented by the memory-guided saccade paradigm, in which a single saccade is made to the remembered position of a unique visual item presented a while before. TMS studies have determined that, after a brief stage of spatial integration in the posterior parietal cortex (inferior to 300 ms), short-term spatial memory (i.e. up to 15-20 s) is controlled by the DLPFC. Behavioral and lesion studies have shown that medium-term spatial memory (between 15-20 s and a few minutes) is specifically controlled by the parahippocampal cortex, before long-term memorization (i.e. after a few minutes) in the hippocampal formation. Lastly, it has been shown that the posterior part of the anterior cingulate cortex, called the cingulate eye field, is involved in motivation and the preparation of all intentional saccades, but not in reflexive saccades. These different but complementary study methods used in humans have thus contributed to a better understanding of both eye movement physiology and general cognitive processes preparing motricity as whole.

Recurrent transitory consciousness loss represents a neurological diagnostic difficulty. A 56 year old man was hospitalised for recurrent stupor episodes. Explorations allowed to exclude hepatic, renal or respiratory failures, epilepsy or sleep disorder. During a stuporous state, since the patient was clearly awakened by flumazenil administration, the retained diagnosis was idiopathic recurrent stupor, a rare and not well-known disease. The authors discuss the possible effect of a treatment with zolpidem, though its pharmacokinetic characteristics did not correspond to the patient manifestations, and the possible responsibility of endogenous benzodiazepines in the genesis of this trouble.

The case of a young female with an acute idiopathic low cerebrospinal fluid pressure is presented. Clinical-imaging manifestations were typical and two consecutive blood patches resulted in a complete and durable resolution of the symptomatology. We present a review of the various investigation and therapeutic techniques.

Two women presented with bilateral internuclear ophthalmoplegia evolving in a few days to complete bilateral horizontal gaze paralysis. Convergence and vertical eye movements were normal. Cerebral MRI showed a few small white matter lesions in the lateral ventricle regions, and, at the brainstem level, a single, small, bilateral lesion affecting the posterior part of the medial pontine tegmentum and responsible for the clinical syndrome. The condition gradually improved in both patients, following a similar progression as at the onset: improvement first involved the adduction movements in both eyes, whereas bilateral abduction paresis still persisted for a few weeks, before complete recovery of eye movements. Bilateral damage to the medial longitudinal fasciculus and subsequent lateral extent of damage to the region of the two abducens emerging fibres may explain the clinical findings. In both cases, the cause was probably multiple sclerosis.

Severe falciparum malaria usually occurs in nonimmune patients, namely children in endemic areas or travelers returning from tropical areas. It generally has one of two outcomes: rapid death or cure without sequelae. Neurologic sequelae have been reported in children but have not been described in detail in adults. The purpose of this study was to determine the clinical spectrum, neuroimaging aspects and long-term outcome of these sequelae. We describe six imported cases of severe malaria with neurologic sequelae in adults, seen in a Parisian university hospital over a 10-year period. The most striking findings were neuropsychological disorders, in particular memory impairment and diffuse white matter damage on magnetic resonance imaging. Only three of the patients had made a full recovery after 6 months.

The history of the French Society of Neurology during the past 25 years is briefly summarised, with special emphasis on the eminent role played by some of its members: Paul Castaigne, of immense stature, and Jean Cambier and Alain Guillard who for many years acted as General Secretary before becoming President. This is followed by a report analysing the scientific work of the Society during the century. It is pointed out that certain topics, such as clinical semiology and infectious pathology, which were much studied in the past, are now largely ignored. Other topics, however, such as multiple sclerosis, vascular pathology, and degenerative pathology are more frequently studied today than in the past. Lastly, an analysis is made of the Society's current membership, from which it is apparent that a special effort will be required on the part of all members to maintain the wide scientific influence that our Society has always exerted.

Lesion studies in monkeys suggest that neocortical subregions of the medial temporal lobe (MTL) carry memory functions independent of the hippocampal formation. The present study investigates possible differential contributions of MTL subregions to spatial memory in humans. Eye movements toward remembered spatial cues (memory-guided saccades) with unpredictably varied memorization delays of up to 30 seconds were recorded in patients with postsurgical lesions of the right MTL, either restricted to the hippocampal formation (n = 3) or including the adjacent neocortex (n = 5) and in 10 controls. Although saccadic targeting errors of patients with selective hippocampal lesions did not differ from controls, saccadic targeting errors of patients with additional neocortical involvement showed a significant and contralaterally pronounced increase at memorization delays above 20 seconds. We conclude that the human medial temporal neocortex carries spatial memory functions independent of the hippocampal formation and distinct from spatial short-term memory.

Sirs: We report a case of Whipple’s disease (WD) with an unusual presentation. The patient was a 22year-old woman with no particular medical history. Three months after an isolated self limited episode of gastro-enteritis, a rapid onset in less than 12 hours of a bilateral myelopathy with a sensory level corresponding to T8 was observed. There was an aseptic lymphocytic meningitis on CSF analyses. MRI showed a medullar lesion enhanced by gadolinium and extending from T1 to T8 on T2weighted images (Fig. 1 A). Despite antibiotic and antiviral therapy, the clinical picture evolved toward the installation, four days later, of stroke-like cerebral disturbances (facial central paralysis, left upper limb weakness and upbeat nystagmus) with secondary deterioration leading to swallowing difficulties and respiratory failure; the patient was placed on mechanical ventilation. Brain MRI showed multiple high signal lesions with no mass effect in the pons and the right peduncle, sub-thalamic region, internal capsule and temporal lobe on FLAIR, diffusion weighted images and T2 (Fig. 1 B). Numerous etiologic investigations undertaken were negative: viral, bacterial, parasitic and fungal serologies, PCRs performed on blood and CSF (including T.whippelii), auto-antibodies and tumor markers screening as well as gastro-colic fibroscopies with salivary gland and duodenal biopsies (Periodic Acid Schiff (PAS) staining was negative). The presence of numerous signal abnormalities on MRI suggestive of vasculitis, supported by the finding of vascular irregularities in the vertebro-basilar system on angiography, led to instituting a corticosteroid treatment with consequent clinical, biological LETTER TO THE EDITORS

Severe deficits of foveal smooth pursuit and optokinetic nystagmus in all directions were electro-oculographically recorded in an 80 year old woman. Magnetic resonance imaging (MRI) showed an infarct involving the postero-inferior part of the vermis (lobules VI to X) and a portion of the left cerebellar hemisphere, with apparent preservation of the flocculus and the brainstem. The role of the vermal lesion in these pursuit eye movement disorders is discussed.

Spinal tape syndrome requires rapid diagnosis and adapted treatment. A relatively small diameter needle inserted parallel to the dura mata fibers is the best preventive measure. The ventral supine position for a few hours followed by a short walk is sufficient. Caffeine may also be prescribed and has been shown to be as effective orally or intravenously. For severe or persistent syndromes, the blood-patch is remarkably effective and simple to use.

We compared horizontal eye movements (visually guided saccades, antisaccades, and smooth pursuit) in control subjects (n = 14) and patients with three forms of autosomal dominant cerebellar ataxias type I: spinocerebellar ataxias 1 and 2 (SCA1, n = 11; SCA2, n = 10) and SCA3/Machado-Joseph disease (MJD) (n = 16). In SCA1, saccade amplitude was significantly increased, resulting in hypermetria. The smooth pursuit gain was decreased. In SCA2, saccade velocity was markedly decreased. The percentage of errors in antisaccades was greatly increased and was significantly correlated with age at disease onset. In addition, a correlation between smooth pursuit gain and the number of trinucleotide repeats was found. In SCA3, gaze-evoked nystagmus was often present as was saccade hypometria and smooth pursuit gain was markedly decreased. Three major criteria, saccade amplitude, saccade velocity, and presence of gaze-evoked nystagmus, permitted the correct assignment of 90% of the SCA1, 90% of the SCA2, and 93% of the patients with SCA3 to their genetically confirmed patient group and, therefore, may help orient diagnoses of SCA1, SCA2, and SCA3 at early clinical stages of the diseases.

A 32-year-old woman, living in Paris, was admitted to our hospital because of ascending weakness and paresthesiae in the lower limbs, associated with dysuria. One month before admission, she had thoracic pain in the left T10 dermatome, abdominal pain and diarrhea, that resolved spontaneously within a few days. Examination confirmed distal asymmetric weakness and dysesthesiae in both lower limbs, up to right T12 and left L1 dermatomes. Deep tendon reflexes were present and symmetric. Right cutaneous plantar response was in extension. There was no meningeal irritation and no rash. Spinal magnetic resonance imaging (MRI) showed intramedullar T2-weighted hyperintensity from T6 to T11, with a contrast-enhancement at level T9 (Fig. 1). CSF examination revealed 25 cells/μL with 50 % of eosinophils, 28 % of lymphocytes, 0.3 g/L of protein and 3.3 mmol/L of glucose. Hematological, biochemical, inflammatory, and immunological blood tests were normal or negative, and the number of peripheral blood eosinophils was within the normal range. HIV serology was negative. Viral polymerase chain reactions in the CSF were negative for HSV, VZV, CMV and EBV. Antibody titers against schistosomiasis, cysticercosis, hydatidosis, amoebiasis and toxoplasmosis were negative in serum. There was no cryptococcus in either the blood or CSF. No parasitic organism was detectable in either the feces or urine. However, antibody titer against Toxocara canis was positive using the ELISA method and was higher in the CSF than in serum (200 in the CSF vs 62 in the serum), suggesting intrathecal Toxocara canis antibody synthesis. Consequently, acute meningo-myelitis due to Toxocara canis was diagnosed. Although symptoms partially disappeared before any treatment, IV administration of mebendazole (800 mg per day for 10 days) was concomitant with an almost complete clinical recovery and total normalization of spinal MRI (Fig. 2).

Two patient with familial cavernous angiomatosis presenting with long lasting variable epilepsy with a poor therapeutic response and variable neurologic impairments are presented here. One of the numerous cavernous angiomas was resected in one case. This last patient remains asymptomatic. Familial cerebral cavernous angiomas are often numerous and disseminated in the brain, therefore clinical manifestations are very polymorphous. Moreover the course of these lesions is variable. Therefore MRI should be performed to every patient presenting with poorly understood neurological symptoms, focal or generalized epileptic seizures or absence in order to look for potentially imputable brain lesions. A reliable genetic marker might be helpful for diagnosis of this disease with a variable penetrance and autosomal dominant inheritance. Then a neurosurgical treatment should be carefully discussed if lesions are accessible and medications are poorly efficient with recurrent neurologic impairments or epilepsy.

A right frontal and left cerebellar diaschisis, resulting from a right pontine infarction, is reported in a patient with complete left hemiplegia. Magnetic resonance imaging and CT scan supported the existence of the pontine infarction. The SPECT-HMPAO-99mTc showed a relative hypoactivity in the right frontal lobe and left cerebellar hemisphere.

Smooth pursuit is a relatively recent eye movement which has developed in frontal-eyed species. The smooth pursuit system is involved during foveal smooth pursuit, the 'rapid' component of OKN slow phase and VOR suppression. The cortical areas controlling smooth pursuit (at the temporo-parieto-occipital junction and in the FEF) send ipsilateral projections onto the pontine nuclei, mainly the DLPN, passing through the anterior part of the midbrain. A midbrain or DLPN lesion results in ipsilateral smooth pursuit impairment (i.e. decreased gain) (Table 1). After the pontine nuclei, all smooth pursuit pathways pass through the cerebellum. They project onto the flocculus, mainly contralaterally (first decussation of the lateral smooth pursuit circuitry), and bilaterally onto the posterior vermis. Eye velocity is encoded in the activity of the floccular Purkinje cells, whereas target velocity is encoded in that of the vermal Purkinje cells. Unilateral floccular lesions and posterior vermal lesions (involving both sides of this structure) result in ipsilateral and bilateral smooth pursuit impairment, respectively. The flocculus sends an ipsilateral inhibitory projection onto the MVN, the y-group nucleus and the SVN, controlling contralateral, upward and perhaps downward smooth pursuit, respectively. Alternatively, the downward smooth pursuit pathway could pass through the dentate nuclei. The MVN sends a contralateral excitatory projection onto the abducens nucleus (second decussation of the lateral smooth pursuit circuitry). These anatomical and physiological characteristics of lateral smooth pursuit pathways, in addition to the results of lesion studies, suggest that, besides the floccular inhibitory Purkinje cell, there is another inhibitory neurone in the circuitry preceding this cell, perhaps within the flocculus itself. The posterior vermis projects onto the fastigial nuclei, which also control smooth pursuit. These nuclei could send efferents to those periabducens cells involved in ipsilateral smooth pursuit. The final part of the pathways involved in vertical smooth pursuit could pass mainly through the BC, originating in the y-group nucleus for upward movement and in the SVN or the dentate nuclei for downward movement. Alternatively, a ventral tegmental tract could transmit upward smooth pursuit signals between the y-group nucleus and the oculomotor nucleus. The MLF also belongs to this vestibulo-oculomotor circuitry, but does not appear to be crucial for vertical smooth pursuit since this eye movement is only partially impaired after MLF lesions. Lastly, parallel to the direct vestibulo-ocular motor nuclei pathways, there are other pathways passing through the brain stem integrators, converting eye velocity signals to eye position signals during all eye movements, including smooth pursuit.(ABSTRACT TRUNCATED AT 400 WORDS)

A case of neurocysticercosis in a Zaïrian patient with clinical and neuro-radiological follow-up is reported. Treatment with praziquantel resulted in the regression of only some of the cysts. Subsequent treatment with albendazole was effective, eliminating most of the remaining lesions. This case illustrates a selective sensitivity of cysts to praziquantel and albendazole in a single patient.

Oculomotor palsies due to lesions of the brain stem may be complete, affecting all types of eye movements in one direction; this reflects a nuclear, internuclear or infractuclear lesion. This may also be disassociated, affecting only one type of eye movements, and this suggests supranuclear lesions. Concerting lateral movements, complete paralysis of abduction, adduction (sparing convergence) or ipsilateral laterality is suggestive of damage to the radicular fibres of the abducencs nucleus (VI), to its internuclear neurons or to the nucleus itself respectively. Isolated paralysis of saccades is in favour of a lesion of the paramedian pontine reticular formation. As regards vertical movements, paralysis of the oculomotor nerve (III), either isolated or associated with complete paralysis of the contralateral rectus superior oculi muscle, suggests a lesion of the radicular fibres of III or of the nucleus itself respectively. Paralysis of downward or both downward and upward saccades indicates the presence of bilateral lesions in the region of the mesencephalic reticular formation. Paralysis of upward saccades alone reflects a unilateral lesion located near the posterior commissure.

A case of normal pressure hydrocephalus associated with neurosyphilis is reported. The outcome was favourable after penicillin therapy and subtraction of CSF.