Neuro Ophthalmology Unit
Neuro Ophthalmology Unit
Clement G.,International Space University |
Tilikete C.,French Institute of Health and Medical Research |
Tilikete C.,University of Lyon |
Tilikete C.,Neuro Ophthalmology Unit |
Courjon J.-H.,French Institute of Health and Medical Research
Neuroscience Letters | Year: 2013
Previous studies in cats revealed that vestibular habituation of the vestibulo-ocular reflex (VOR) only occurs when velocity steps are delivered during the secondary phase nystagmus, suggesting that the presence of anti-compensatory slow phases may trigger the habituation process. We verified this property in humans by comparing vestibular habituation of VOR and sensation of rotation when steps were delivered either immediately after the perception of self-rotation had stopped, which is shortly before the nystagmus reverses direction; or when steps were delivered 60. s later, i.e. during the secondary phase. Vestibular habituation of the VOR occurred in both instances. However, the decrease in VOR peak slow phase velocity and time constant was larger when steps were delivered after nystagmus reversal compared to before nystagmus reversal. The duration of the perception of self-rotation habituated equally for both conditions. These results confirm that VOR habituation fully develops only when velocity steps are delivered after the primary phase nystagmus. This finding may be helpful for minimizing the impact of repetitive vestibular stimuli in protocols using crossover design for drug studies, testing recovery in vestibular patients, or training people for different gravitoinertial environments. © 2013 Elsevier Ireland Ltd.
Shofty B.,Dana Childrens Hospital |
Ben-Sira L.,Pediatric Radiology Unit |
Constantini S.,Dana Childrens Hospital |
Freedman S.,Dana Childrens Hospital |
Kesler A.,Neuro Ophthalmology Unit
American Journal of Neuroradiology | Year: 2012
BACKGROUND AND PURPOSE: IIH is a disorder associated with increased intracranial pressure with no clinical, laboratory, or radiologic evidence of an intracranial space-occupying lesion. The aim of this study was to establish ONSD standards of healthy pediatric subjects and compare the normal measurements with those of patients with IIH. MATERIALS AND METHODS: One hundred fifteen MR imaging studies of children 4 months to 17 years of age were blinded and reviewed by a pediatric neuroradiologist. A total of 230 optic nerves were measured. Eighty-six MR imaging examinations were performed in apparently healthy subjects. This control group included subjects who underwent MR imaging for various reasons, and their MR imaging findings were interpreted as normal. Twenty-nine MR imaging examinations were performed in patients with documented IIH. The ONSD was measured 1 cm anterior to the optic foramina on an axial T2 sequence. For statistical analysis, both patients and controls were stratified into 4 age groups (I, 0-3 years; II, 3-6 years; III, 6-12 years; IV, 12-18 years). RESULTS: The mean ONSD of the control group in all age groups (I, 3.1 mm; II, 3.41 mm; III, 3.55 mm; IV, 3.56 mm) was significantly smaller than the mean ONSD of patients (I, 4.35 mm; II, 4.37 mm; III, 4.25 mm; IV, 4.69 mm). A positive correlation between age and ONSD (r = 0.414, P < .01) was found in the control group. CONCLUSIONS: According to our study, in pediatric patients with IIH, the ONSD is significantly larger than that in healthy controls regardless of age group and sex. This measurement might prove to be an auxiliary tool in the diagnosis of increased intracranial pressure in pediatric patients.
Kesler A.,Neuro ophthalmology Unit |
Vakhapova V.,Tel Aviv Sourasky Medical Center |
Korczyn A.D.,Tel Aviv University |
Naftaliev E.,Neuro ophthalmology Unit |
Neudorfer M.,Neuro ophthalmology Unit
Clinical Neurology and Neurosurgery | Year: 2011
Objectives: Mild cognitive impairment (MCI) may represent a transition to early Alzheimer's disease (AD). The retinal nerve fiber layer (RNFL) is composed of axons originating in retinal ganglion cells that eventually form the optic nerves. Previous studies have shown that degenerative changes occur in optic nerve fibers and manifested as thinning of RNFL in patients with AD. The objective of this study was to assess the relationship between MCI, AD and loss of RNFL. Patients and methods: In this study, patients fulfilling diagnostic criteria for MCI (n = 24), AD (n = 30) and cognitively normal age-matched controls (n = 24) have undergone neuro-ophthalmologic and optical coherence tomography (OCT) examinations to measure RNFL thickness. Results: There was a significant decrease in RNFL thickness in both study groups (AD and MCI) compared to the control group, particularly in the inferior quadrants of the optic nerve head, while the superior quadrants were significantly thinner only in AD. Although AD patients may have more severe changes than MCI cases, the differences were statistically nonsignificant. Furthermore among AD patients, there was no relation to the severity of the dementia. Conclusions: Our data confirm the retinal involvement in AD, as reflected by loss of axons in the optic nerves. © 2011 Elsevier B.V.
Kesler A.,Neuro ophthalmology Unit |
Kesler A.,Tel Aviv University |
Stolovic N.,Neuro ophthalmology Unit |
Bluednikov Y.,Israel Center for Disease Control |
And 2 more authors.
European Journal of Neurology | Year: 2014
Background and purpose: Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder related to increased intracranial pressure without clinical, laboratory or radiological evidence of an intracranial space occupying lesion or cerebral sinus vein thrombosis, predominantly affecting obese women of childbearing age. Our aim was to determine the incidence and clinical features of IIH in Israel. Methods: In a cross-sectional study, all medical records of patients discharged from the hospital with a primary diagnosis of IIH during 2005-2007 were reviewed. Results: Four hundred and twenty-eight patients with a new onset of IIH were diagnosed. The average annual incidence rate was 2.02 per 100 000 with an incidence of 3.17 per 100 000 for women and 0.85 per 100 000 for men. The incidence rate in females of childbearing age (18-45) was 5.49 per 100 000. The female to male ratio for >17 years old was 6.1:1 (252 females and 41 males) and 2.1:1 (60 females and 28 males) for ages 11-17. Obesity was documented in 83.4% of patients. Body mass index (BMI) data were available for 159 (37.1%) patients; of these, 59.1% had a BMI ≥ 30. Conclusion: The incidence of IIH in Israel has increased during the last decade. This finding could be related to the increasing rates of obesity. The association of IIH and obesity should be further explored especially with regard to the effect of weight reduction for primary prevention. © 2014 EAN.
Kaeser P.-F.,University of Lausanne |
Kawasaki A.,Neuro ophthalmology Unit
Neurologic Clinics | Year: 2010
Neurologists are frequently consulted because of a pupillary abnormality. An unequal size of the pupils, an unusual shape, white colored pupils, or a poorly reactive pupil are common reasons for referral. A directed history and careful observation of the iris and pupil movements can bear out ocular pathology such as congenital or structural anomalies as the cause of abnormal pupils. Thereafter, it is important to evaluate the neurologic causes of anisocoria and poor pupil function. The first part of this article emphasizes pupillary abnormalities frequently encountered in infants and children and discusses some of the more common acquired iris structural defects. The second part focuses on evaluation of lesions in the neural pathways that result in pupillary dysfunction, with particular attention to those conditions having neurologic, systemic, or visual implications. © 2010 Elsevier Inc.
Kesler A.,Neuro Ophthalmology Unit
Harefuah | Year: 2013
Neuro-ophthalmology focuses on the diagnosis and treatment of visual disorders related to the neurological system rather than the globe itself. Being a subspecialty of both neurology and ophthalmology, it requires specialized training and expertise in diseases of the eye, brain, nerves and muscles. Commonly encountered pathologies in neuro-ophthalmology include: optic neuropathies (such as optic neuritis and ischemic optic neuropathy), visual field loss (transient, constant, unexplained), transient visual loss, unspecified visual disturbances, diplopia, abnormal eye movements, thyroid eye disease, myasthenia gravis, anisocoria, and eyelid abnormalities. The current issue of "Harefuah" is dedicated to contemporary knowledge in neuro-opthalmology, and spans from studies of neuromyelitis optica (NMO), ischemic optic neuropathies, and optic neuropathies induced by phosphodiesterase inhibitors, to the management of sight-threatening carotid-cavernous fistulas, and more. These studies emphasize the importance of an interdisciplinary treatment team consisting of a neuro-ophthalmologist, a neuro-radiologist, and sometimes, even a neuro-surgeon. Such an approach may prove to be beneficial to the patient, by optimizing follow-up and treatment decisions. This issue emphasizes how a correct and timely diagnosis is of paramount significance in patients with neuro-ophthalmological disorders.
Szatmary G.,Neuro Ophthalmology Unit
Current Neurology and Neuroscience Reports | Year: 2013
Neoplastic leptomeningeal disease (NLD), which encompasses both primary and secondary leptomeningeal tumors, has a devastating impact on the life of cancer patients. The present diagnostic technical armamentarium is insufficient for early diagnosis of NLD. However, NLD may present with subtle neuro-ophthalmic features at a time of relatively small tumor burden, which gives the provider first encountering these patients the window of opportunity for early diagnosis and consequently improved life expectancy and quality of life of these patients. Therefore, familiarity with early, often subtle neuro-ophthalmic features is an essential tool for diagnosing these patients prior to the development of fixed deficits, which usually portend a dismal prognosis. Future evolving laboratory and neuroimaging technologies are expected to advance our understanding of underlying pathophysiology and early detection of NLD. This paper provides an up-to-date review and synthesis of the current literature with focus on neuro-ophthalmic features and their underlying pathophysiology. © 2013 Springer Science+Business Media New York.
Borruat F.-X.,Neuro Ophthalmology Unit
Current Opinion in Neurology | Year: 2013
PURPOSE OF REVIEW: Oculopalatal tremor (OPT) is an acquired disorder resulting from the interruption of a specific brainstem circuitry, the dentato-rubro-olivary pathway or Guillain-Mollaret triangle. The recent literature on OPT and olivary hypertrophy was reviewed with specific interest regarding causes, diagnostic procedures, physiopathology and therapies. RECENT FINDINGS: OPT is associated with inferior olivary hypertrophy, and recent findings have provided a better understanding of its intimate mechanisms. A dual-mechanism model, combining an oscillator (inferior olive) and a modulator/amplifier (cerebellum), best explains the development of OPT. Electrotonic coupling and specific Ca channels contribute to oscillations of inferior olivary nucleus neurons in OPT. Improvement of visual symptoms can be achieved with oral gabapentin or memantine. SUMMARY: Both the neuronal circuitry and the physiopathology of OPT are now better understood. This opens up an era of specific therapy for this rare cause of disabling oscillopsia. © 2013 Wolters Kluwer Health | Lippincott Williams &Wilkins.
Kesler A.,Neuro ophthalmology unit |
Kliper E.,Neuro ophthalmology unit |
Shenkerman G.,Institute of Endocrinology |
Stern N.,Institute of Endocrinology
Ophthalmology | Year: 2010
Objective: To characterize the obesity phenotype(s) in patients with idiopathic intracranial hypertension (IIH). Design: Database study. Participants: We studied 44 consecutive patients with IIH, in addition to 184 women attending the obesity clinic of the same medical center and 199 obese women participating in the first Israeli national survey on health and nutrition conducted in 1999 and 2000. Methods: Anthropometric parameters were compared with those of 2 control groups of the same age range. Main Outcome Measures: Weight, height, and waist and hip circumference were measured. Results: Forty subjects, comprising 91.0% of this cohort, were either overweight (body mass index, 25.0-29.9 kg/m2) or obese (body mass index ≥ 30 kg/m2). Mean waist circumference was 95.3 cm for IIH, 99.8 cm for the national survey, and 114.5 cm for the obesity clinic cohort (P<0.001), whereas hip circumference was 121 cm for IIH, 118.4 cm for the national survey, and 125.8 cm (P = not significant) for the obesity clinic cohorts. Waist-to-hip ratio, a descriptive measure of body fat distribution approximately reflecting upper to lower body fat ratio, was 0.79 in the patients with IIH, 0.84 in the national survey group, and 0.91 in the obesity clinic cohort (P<0.001; all comparisons were adjusted for age and body mass index). Conclusions: In IIH, fat tends to preferentially accumulate in the lower body relative to other obese women of the same range. Whereas most complications of obesity, such as hypertension, diabetes, dyslipidemia, and the metabolic syndrome, are linked to upper body adiposity, IIH may represent a unique condition potentially induced by nonvisceral fat-related mechanisms. Financial Disclosure(s): The authors have no proprietary or commercial interest in any materials discussed in this article. © 2010 American Academy of Ophthalmology.
Krashin-Bichler I.,Neuro Ophthalmology Unit
Harefuah | Year: 2013
Erectile dysfunction medications such as sildenafil citrate (Viagra) or tadalafil (Cialis) are commonly prescribed worldwide. They are selective phosphodiesterase-5 inhibitor and partial phosphodiesterase-6 inhibitors causing smooth muscle relaxation in the corpus cavernosum, allowing penile vasodilatation and erection in response to sexual stimuli. Over the years, there have been an increasing number of case reports concerning patients who developed ischemic optic neuropathy soon after the ingestion of these drugs. Although a cause and effect relationship between usage of the drugs and the development of ischemic optic neuropathy is difficult to prove, it is common nowadays to advise patients, especially those suffering from diabetes, hypertension, and ischemic heart disease, regarding the potential risk of visual loss due to ischemic optic neuropathy and treatment with erectile dysfunction drugs. Patients who were diagnosed with ischemic optic neuropathy soon after the ingestion of these erectile dysfunction drugs should be warned about a similar event in their fellow eye and should be advised regarding drug discontinuation.