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Nystagmus

Distribution by Scientific Domains

Medical Sciences	91%
Life Sciences	6%

Distribution within Medical Sciences

Neurology	40%
Anesthesia & Pain Management	4%
11 Other Subdomains	56%

Selected Abstracts

Central Nystagmus Induced by Deep-Brain Stimulation for Epilepsy

EPILEPSIA, Issue 1 2000
Article first published online: 19 SEP 200
First page of article [source]

Correlation of anatomy and function in medulla oblongata infarction

EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2009
C. Eggers
Background:, A presentation of all aspects of the dorsolateral medulla oblongata syndrome is clinically very rare to find. In most cases patients present with fragmentary symptoms, e.g. ipsilateral axial lateropulsion, nystagmus, dysarthria, dysphagia or hemiataxia. However, the clinical presentation and lesion anatomy at the level of the medulla oblongata is still unsatisfactory. The aim of this study was to correlate the functional deficit with structural MRI-data. Methods:, We included thirteen patients (eight male, five female, mean age 65.5) with medulla oblongata infarction with clinically predominant ipsilateral axial lateropulsion and correlated clinical with structural deficits. Results:, Magnetic resonance imaging lesion mapping demonstrated ipsilateral axial lateropulsion to result from lesions of the spinocerebellar tract, the inferior cerebellar peduncle or the inferior vestibular nucleus. Nystagmus was associated with lesions of the inferior vestibular nucleus, dissociated sensory loss with the spinothalamic tract and hemiataxia with the spinocerebellar tract. Conclusions:, Correlating dysfunction and lesion anatomy is a promising approach to enhance our knowledge on medulla oblongata topography. [source]

Ocular complications of neurological therapy

EUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2005
S. Hadjikoutis
Treatments used for several neurological conditions may adversely affect the eye. Vigabatrin-related retinal toxicity leads to a visual field defect. Optic neuropathy may result from ethambutol and isoniazid, and from radiation therapy. Posterior subcapsular cataract is associated with systemic corticosteroids. Transient refractive error changes may follow treatment with acetazolamide or topiramate, and corneal deposits and keratitis with amandatine. Intraocular pressure can be elevated in susceptible individuals by anticholinergic drugs, including oxybutynin, tolterodine, benzhexol, propantheline, atropine and amitriptyline, and also by systemic corticosteroids and by topiramate. Nystagmus, diplopia and extraocular muscle palsies can occur with antiepileptic drugs, particularly phenytoin and carbamazepine. Ocular neuromyotonia can follow parasellar radiation. Congenital ocular malformations can result from in utero exposure to maternally prescribed sodium valproate, phenytoin and carbamazepine. Neurologists must be aware of potential ocular toxicity of these drugs, and appropriately monitor for potential adverse events. [source]

Head-shaking Nystagmus Predicts Greater Dizziness Handicap

THE LARYNGOSCOPE, Issue S3 2010
Simon Angeli MD
No abstract is available for this article. [source]

Crossover trial of gabapentin and memantine as treatment for acquired nystagmus

ANNALS OF NEUROLOGY, Issue 5 2010
Matthew J. Thurtell MBBS
We conducted a masked, crossover, therapeutic trial of gabapentin (1,200mg/day) versus memantine (40mg/day) for acquired nystagmus in 10 patients (aged 28,61 years; 7 female; 3 multiple sclerosis [MS]; 6 post-stroke; 1 post-traumatic). Nystagmus was pendular in 6 patients (4 oculopalatal tremor; 2 MS) and jerk upbeat, hemi-seesaw, torsional, or upbeat-diagonal in each of the others. For the group, both drugs reduced median eye speed (p < 0.001), gabapentin by 32.8% and memantine by 27.8%, and improved visual acuity (p < 0.05). Each patient improved with 1 or both drugs. Side effects included unsteadiness with gabapentin and lethargy with memantine. Both drugs should be considered as treatment for acquired forms of nystagmus. ANN NEUROL 2010;67:676,680 [source]

Surveillance of vision and ocular disorders in children with Down syndrome

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2007
Elma Stephen MBBS MD MRCPCH
Children with Down syndrome have a high prevalence of ocular disorders. The UK Down's Syndrome Medical Interest Group (DSMIG) guidelines for ophthalmic screening were locally implemented into a protocol that included neonatal eye examination by an opthalmologist and a comprehensive ophthalmological examination (cycloplegic refraction, ophthalmoscopy, and orthoptic assessement) by at least the age of 3 years, followed by preschool follow-up as indicated. We audited retrospectively surveillance for ocular disorders before and after the DSMIG-based guidelines were locally adopted in 1995. Results were compared for children born before and after the implementation of screening guidelines. A total of 81 children (43 females, 38 males) with Down syndrome were identified. After the DSMIG protocol, 34/36 children received a full ophthalmological examination in the neonatal period, compared with 9/27 children before 1995 (p<0.001). Neonatal screening resulted in the detection of cataracts in three infants. Mean age of first comprehensive ophthalmic screening outside the neonatal period was similar in the two groups (1y 6mo before guidelines vs 1y 9mo after), as were the proportion of children receiving preschool eye checks (27/30 before; 17/18 after). Overall, 65.7% children were screened in accordance with the guidelines, improving to 100% in recent years. At school age, 43% of the study population had significant refractive errors, with 27% having hypermetropia and astigmatism. Earlier prescription of glasses for refractive errors was seen (mean age 5y 6mo before guidelines; 3y 6mo after; p<0.001). Prevalence of other ocular disorders included strabismus (34/72, 47%), nasolacrimal duct obstruction (26/73, 35.6%), cataracts (5/64, 7.8%), and nystagmus (12/72, 16%). Establishment of the DSMIG-based local protocol has streamlined ocular surveillance. It is anticipated that this will improve developmental and functional outcomes in Down syndrome. [source]

Smooth ocular pursuit in Chiari type II malformation

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 4 2007
Michael S Salman MRCP PhD
Chiari type II malformation (CII) is a congenital anomaly of the cerebellum and brainstem, both important structures for processing smooth ocular pursuit. CII is associated with myelomeningocele and hydrocephalus. We investigated the effects of CII on smooth pursuit (SP) eye movements, and determined the effects of spinal lesion level, number of shunt revisions, nystagmus, and brain dysmorphology on SP. SP was recorded using an infrared eye tracker in 21 participants with CII (11 males, 10 females; age range 8-19y, mean 14y 3mo [SD 3y 2mo]). Thirty-eight healthy children (21 males, 17 females) constituted the comparison group. Participants followed a visual target moving sinusoidally at ± 10° amplitude, horizontally and vertically at 0.25 or 0.5Hz. SP gains, the ratio of eye to target velocities, were abnormal in the CII group with nystagmus (n= 8). The number of shunt revisions (range 0-10), brain dysmorphology, or spinal lesion level (n= 15 for lower and n= 6 for upper spinal lesion level) did not correlate with SP gains. SP is impaired in children with CII and nystagmus. Abnormal pursuit might be related to the CII dysgenesis or to effects of hydrocephalus. The lack of effect of shunt revisions and abnormal tracking in participants with nystagmus provide evidence that it is related primarily to the cerebellar and brainstem malformation. [source]

Multiple sensitive periods in human visual development: Evidence from visually deprived children

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2005
Terri L. Lewis
Abstract Psychophysical studies of children deprived of early visual experience by dense cataracts indicate that there are multiple sensitive periods during which experience can influence visual development. We note three sensitive periods within acuity, each with different developmental time courses: the period of visually-driven normal development, the sensitive period for damage, and the sensitive period for recovery. Moreover, there are different sensitive periods for different aspects of vision. Relative to the period of visually driven normal development, the sensitive period for damage is surprisingly long for acuity, peripheral vision, and asymmetry of optokinetic nystagmus, but surprisingly short for global motion. A comparison of results from unilaterally versus bilaterally deprived children provides insights into the complex nature of interactions between the eyes during normal visual development. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 163,183, 2005. [source]

Efficacy and Safety of Oral Lacosamide as Adjunctive Therapy in Adults with Partial-Onset Seizures

EPILEPSIA, Issue 7 2007
Elinor Ben-Menachem
Summary:,Purpose: To evaluate the efficacy and safety of lacosamide when added to 1 or 2 antiepileptic drugs (AEDs) in adults with uncontrolled partial-onset seizures, and assess plasma concentrations of concomitant AEDs to determine any potential for drug interactions. Methods: During this multicenter, double-blind, placebo-controlled trial, patients were randomized to placebo or lacosamide 200, 400, or 600 mg/day after an 8-week baseline period. Lacosamide was titrated in weekly increments of 100 mg/day over 6 weeks and maintained for 12 weeks. Results were analyzed on an intention-to-treat basis. Results: Four hundred eighteen patients were randomized and received trial medication; 312 completed the trial. The median percent reduction in seizure frequency per 28 days was 10%, 26%, 39%, and 40% in the placebo, lacosamide 200, 400, and 600 mg/day treatment groups, respectively. The median percent reduction in seizure frequency over placebo was significant for lacosamide 400 mg/day (p = 0.0023) and 600 mg/day (p = 0.0084). The 50% responder rates were 22%, 33%, 41%, and 38% for placebo, lacosamide 200, 400, and 600 mg/day, respectively. The 50% responder rate over placebo was significant for lacosamide 400 mg/day (p = 0.0038) and 600 mg/day (p = 0.0141). Adverse events that appeared dose-related included dizziness, nausea, fatigue, ataxia, vision abnormal, diplopia, and nystagmus. Lacosamide did not affect mean plasma concentrations of concomitantly administered AEDs. Conclusions: In this trial, adjunctive lacosamide significantly reduced seizure frequency in patients with uncontrolled partial-onset seizures. Along with favorable pharmacokinetic and tolerability profiles, these results support further development of lacosamide as an AED. [source]

Predictive Clinical Factors for the Differential Diagnosis of Childhood Extratemporal Seizures

EPILEPSIA, Issue 8 2005
András Fogarasi
Summary:,Purpose: To describe predictive clinical factors for the differentiation between childhood frontal lobe epilepsy (FLE) and posterior cortex epilepsy (PCE). Methods: Two independent, blinded investigators analyzed 177 seizures from 35 children (aged 11 months to 12 years) with extratemporal epilepsy selected by postoperative seizure-free outcome. Semiologic seizure components and different periictal signs were observed. Age at onset, auras, seizure frequency, and nocturnal dominance, as well as surgical and histopathologic data, were collected from medical charts. Results: Twenty patients had FLE, and 15 had PCE. Patients from both groups had daily seizures without significant differences in frequency but with higher nocturnal dominance in children with FLE (p < 0.05). Visual aura, nystagmus, and versive seizure were observed exclusively in the PCE group, whereas somatosensory aura and hypermotor seizures appeared only in FLE. Tonic seizures were significantly more frequent in FLE (p < 0.01), whereas the presence of clonic seizure (FLE; p = 0.07) and postictal nose-wiping (PCE; p = 0.05) showed only a trend to localize the seizure-onset zone. Myoclonic seizures, epileptic spasms, psychomotor seizures, atonic seizures, oral and manual automatisms, as well as vocalization and eye deviation appeared in both groups without significant differences in their frequency. Conclusions: Characteristic features described in adults' extratemporal epilepsies were frequently missing during childhood seizures, especially in infants and preschool children. Ictal features help only a little in differentiating childhood FLE from PCE. Nocturnal appearance and the type of aura have high localizing value; therefore an accurate history taking is still an essential element of pediatric presurgical evaluation. [source]

Correlation of anatomy and function in medulla oblongata infarction

Effects of hyperventilation on fast goal-directed limb movements in spinocerebellar ataxia type 6

EUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2001
M.-U. Manto
It has been shown previously that hyperventilation modifies the features of the nystagmus in cerebellar patients (Walker and Zee, 1999). It has been hypothesized that hyperventilation influences the oculomotor control through a metabolic effect on cerebellar calcium channels, which play a critical role in the firing behaviour of neuronal populations in the cerebellum. This hypothesis has been tested here by analysing fast goal-directed limb movements before and after hyperventilation in spinocerebellar ataxia type 6 (SCA-6), a disease associated with a polyglutamine expansion in the , 1-A voltage-dependent calcium channel. Cerebellar hypermetria associated with fast distal single-joint movements was found to be increased following hyperventilation in patients presenting SCA-6 but remained unchanged in patients with idiopathic late-onset cerebellar degeneration (ILOCA). This is a new provocative test to enhance distal dysmetria in SCA-6. The present results strengthen the hypothesis of Walker and Zee. It is suggested that hyperventilation enhances the defective calcium transfers in SCA-6, resulting in an impairment of the calcium influx in particular into Purkinje cells involved in the control of fast goal-directed voluntary movements. [source]

Direction-dependent visual cortex activation during horizontal optokinetic stimulation (fMRI study)

HUMAN BRAIN MAPPING, Issue 4 2006
Sandra Bense
Abstract Looking at a moving pattern induces optokinetic nystagmus (OKN) and activates an assembly of cortical areas in the visual cortex, including lateral occipitotemporal (motion-sensitive area MT/V5) and adjacent occipitoparietal areas as well as ocular motor areas such as the prefrontal cortex, frontal, supplementary, and parietal eye fields. The aim of this functional MRI (fMRI) study was to investigate (1) whether stimulus direction-dependent effects can be found, especially in the cortical eye fields, and (2) whether there is a hemispheric dominance of ocular motor areas. In a group of 15 healthy subjects, OKN in rightward and leftward directions was visually elicited and statistically compared with the control condition (stationary target) and with each other. Direction-dependent differences were not found in the cortical eye fields, but an asymmetry of activation occurred in paramedian visual cortex areas, and there were stronger activations in the hemisphere contralateral to the slow OKN phase (pursuit). This can be explained by a shift of the mean eye position of gaze (beating field) in the direction of the fast nystagmus phases of approximately 2.6 degrees, causing asymmetrical visual cortex stimulation. The absence of a significant difference in the activation pattern of the cortical eye fields supports the view that the processing of eye movements in both horizontal directions is mediated in the same cortical ocular motor areas. Furthermore, no hemispheric dominance for OKN processing was found in right-handed volunteers. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source]

Monocular visual activation patterns in albinism as revealed by functional magnetic resonance imaging

HUMAN BRAIN MAPPING, Issue 1 2004
Bernd Schmitz
Abstract Human albinism is characterized by a disturbance of the chiasmatic projection system leading to predominant representation of just one eye in the contralateral hemisphere. Patients show congenital nystagmus without perceiving oscillopsia. The purpose of the present study was to demonstrate the consequences of atypical chiasmatic crossing with monocular visual stimulation using functional magnetic resonance imaging (fMRI). Sixteen patients with albinism and fifteen normally pigmented controls were stimulated with a monocular visual activation paradigm using flickering checkerboards. In patients, we observed contralaterally dominated activation of visual cortices correlating to clinical albinism parameters. This confirms albinism as a continuous range of hypopigmentation disorders. Additionally, albinos showed activation of the superior colliculus and of visual motion areas although the stimulus was stationary. Activation of visual motion areas is due probably to congenital nystagmus without a conscious correlate like oscillopsia. Hum. Brain Mapping 23:40,52, 2004. © 2004 Wiley-Liss, Inc. [source]

Dissecting the pathogenic mechanisms of mutations in the pore region of the human cone photoreceptor cyclic nucleotide-gated channel,

HUMAN MUTATION, Issue 7 2010
Katja Koeppen
Abstract The CNGA3 gene encodes the A3 subunit of the cone photoreceptor cyclic nucleotide-gated (CNG) channel, an essential component of the phototransduction cascade. Certain mutations in CNGA3 cause autosomal recessive achromatopsia, a retinal disorder characterized by severely reduced visual acuity, lack of color discrimination, photophobia, and nystagmus. We identified three novel mutations in the pore-forming region of CNGA3 (L363P, G367V, and E376K) in patients diagnosed with achromatopsia. We assessed the expression and function of channels with these three new and two previously described mutations (S341P and P372S) in a heterologous HEK293 cell expression system using Western blot, subcellular localization on the basis of immunocytochemistry, calcium imaging, and patch clamp recordings. In this first comparative functional analysis of disease-associated mutations in the pore of a CNG channel, we found impaired surface expression of S341P, L363P, and P372S mutants and reduced macroscopic currents for channels with the mutations S341P, G367V, and E376K. Calcium imaging and patch clamp experiments after incubation at 37°C revealed nonfunctional homo- and heteromeric channels in all five mutants, but incubation at 27°C combined with coexpression of the B3 subunit restored residual function of channels with the mutations S341P, G367V, and E376K. Hum Mutat 31:830,839, 2010. © 2010 Wiley-Liss, Inc. [source]

Evaluation of the cognitive, psychomotor and pharmacokinetic profiles of rupatadine, hydroxyzine and cetirizine, in combination with alcohol, in healthy volunteers

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 1 2006
Manuel J. Barbanoj
Abstract Introduction The Central Nervous System (CNS) impairment induced by moderate alcohol (ALC) ingestion may be enhanced if other drugs are taken simultaneously. Rupatadine (RUP) is a new H1 -antihistamine which also inhibits platelet activating factor (PAF) release in inflammatory reactions. Objective The main aim of the study was to assess the effects of ALC 0.8,g/Kg on RUP (10,mg and 20,mg) CNS effects. An evaluation of alcohol and RUP pharmacokinetics was also attained. Methods Eighteen healthy young volunteers of both sexes participated in a phase I, randomised, crossover, double-blind, placebo-controlled study. At 2-week intervals they received six treatments: (a) placebo (PLA), (b) ALC alone and ALC in combination with: (c) hydroxyzine 25,mg (HYD), (d) cetirizine 10,mg (CET), (e) RUP 10,mg or (f) RUP 20,mg. At baseline and several times thereafter, seven psychomotor performance tests (finger tapping, fine motoric skills, nystagmus, temporal estimation, critical-flicker-fusion frequency, ,d2' cancellation, simple reaction) and eleven subjective self-reports (drunkenness, sleepiness, alertness, clumsiness, anger, inattentiveness, efficiency, happiness, hostility, interest and extraversion) were carried out. Two-way (treatment, time) ANOVAs for repeated measures to each variable together with a multivariate non-parametric approach were applied. Plasma concentrations of alcohol, and of RUP and its metabolites, were quantified by validated immunofluorescence and LC/MS/MS methods, respectively. Plasma-time curves for all compounds were analysed by means of model-independent methods. Results The combination of alcohol with HYD, CET and RUP 20,mg produced more cognitive and psychomotor impairment as compared to alcohol alone, being the combination of alcohol and HYD the one which induced the greatest deterioration. The combination of alcohol and RUP 10,mg could not be differentiated from ALC alone. Subjective self-reports reflect effects on metacognition after the combination of alcohol with HYD and CET i.e. the increased objective impairment observed was not subjectively perceived by the subjects. No significant differences were obtained when comparing alcohol plasma concentrations assessed after the treatments evaluated. RUP showed a lineal kinetic relationship after 10 and 20,mg with a higher exposition to both metabolites assayed. Conclusions Present results showed that single oral doses of rupatadine 10,mg in combination with alcohol do not produce more cognitive and psychomotor impairment than alcohol alone. Higher doses of rupatadine, in combination with alcohol, may induce cognitive and psychomotor deterioration as hydroxyzine and cetirizine at therapeutic doses. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Uncommon skin lesion in a patient with ataxia-telangiectasia

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2008
Chinedu Ivonye MD
A 20-year-old African-American man, with a history of ataxia-telangiectasia diagnosed at the age of one year, presented to the hospital with fever, cough, and headache of 2 days' duration. The fever was of high grade, associated with chills and rigors. The headache was frontal in location, constant, pounding in nature, and associated with photophobia and phonophobia; there was no neck pain, no neck stiffness, and no blurring of vision. The patient complained of facial pain. There were no relieving or aggravating factors. The family denied any change in mental status. ,The cough was productive of yellowish sputum. There was associated rhinorrhea. The patient complained of nausea and vomiting with the headache. A review of other systems was negative. ,On presentation in the emergency room, the patient was tachypneic, febrile, and tachycardic. He was oriented to time, place, and person. His neck was supple and meningeal signs were negative. He had maxillary sinus tenderness. Neurologic examination revealed nystagmus, ocular telangiectasia (Fig. 1), ataxia, and globally decreased muscle strength. Skin examination showed hypopigmented areas on all four extremities, the face, and neck (Figs 1,4), without involvement of the trunk. The rest of the physical examination was unremarkable. Figure 1. Area of vitiligo on the neck with premature graying of the hair Figure 2. Vitiligo on the hands Figure 3. Vitiligo involving the legs Figure 4. Ocular telangiectasia ,The leukocyte count was elevated at 19,600/mcL, with a differential of neutrophils (84%), monocytes (11%), and lymphocytes (5%). Hemoglobin and hematocrit were normal. Chemistry and chest X-ray were normal. ,Computed tomography scan of the head showed acute sinusitis and cerebellar atrophy consistent with ataxia-telangiectasia. ,A lumbar puncture was performed, and cerebrospinal fluid findings were suggestive of aseptic meningitis. ,The patient was treated for aseptic meningitis and acute sinusitis with acyclovir and ceftriaxone. The leukocyte count normalized, the patient remained afebrile, and was asymptomatic after 2 days of treatment with antimicrobials. The rest of the hospital stay was uneventful. [source]

Post-operative nystagmus and anisocoria due to serotonin toxicity?

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2009
D. Gokcinar
No abstract is available for this article. [source]

Pathological Laughing As a Manifestation in a Clinically Isolated Brainstem Syndrome: A Case Report

JOURNAL OF NEUROIMAGING, Issue 3 2009
Belgin Kocer MD
ABSTRACT The prevalence of pathological laughing and crying in multiple sclerosis (MS) is 10%. It has been speculated that the anatomical lesion responsible for the pathological laughing is located in the pontine base, prefrontal cortex, and cerebellum. We report an 18-year-old male patient presenting with pathological laughing and hypomania. In his neurological examination, he had a euphoric effect with ataxic walking and dysarthria speech. He had a bilateral conjugated gaze limitation, with a prominent bilateral horizontal nystagmus on left gaze, dysmetria, dysdiadokokinesia, and remarkable dysfunction in a heel-to-shin test on the left. The IgG index in cerebrospinal fluid was normal with an oligoclonal band was present. In cranial MRI, there was a lesion on central pons which was hypointense in T1 images with contrast enhancement and hyperintense in T2 and flair images. Also another lesion in right brachium pontis which did not contrast enhancement but was hyperintense on T2 and flair images was present. There was an elevation of myoinositol/creatine ratio and choline and a reduction of NAA in proton MR spectroscopy. MR spectroscopic evaluation of the patient demonstrated the demyelination process. There has been no report of patients in whom pathological laughter was the presenting symptom of clinically isolated brainstem syndrome. [source]

Decreased cortical inhibition and yet cerebellar pathology in ,familial cortical myoclonic tremor with epilepsy'

MOVEMENT DISORDERS, Issue 16 2007
Anne-Fleur van Rootselaar MD
Abstract Cortical hyperexcitability is a feature of "familial cortical myoclonic tremor with epilepsy" (FCMTE). However, neuropathological investigations in a single FCMTE patient showed isolated cerebellar pathology. Pathological investigations in a second FCMTE patient, reported here, confirmed cerebellar Purkinje cell degeneration and a normal sensorimotor cortex. Subsequently, we sought to explore the nature of cerebellar and motor system pathophysiology in FCMTE. Eye movement recordings and transcranial magnetic stimulation performed in six related FCMTE patients showed impaired saccades and smooth pursuit and downbeat nystagmus upon hyperventilation, as in patients with spinocerebellar ataxia type 6. In FCMTE patients short-interval intracortical inhibition (SICI) was significantly reduced. Resting motor threshold, recruitment curve, silent period, and intracortical facilitation were normal. The neuropathological and ocular motor abnormalities indicate cerebellar involvement in FCMTE patients. Decreased SICI is compatible with intracortical GABAA -ergic dysfunction. Cerebellar and intracortical functional changes could result from a common mechanism such as a channelopathy. Alternatively, decreased cortical inhibition may be caused by dysfunction of the cerebello-thalamo-cortical loop as a result of primary cerebellar pathology. © 2007 Movement Disorder Society [source]

Spinocerebellar ataxia 14: Novel mutation in exon 2 of PRKCG in a German family

MOVEMENT DISORDERS, Issue 2 2007
Dagmar Nolte PhD
Abstract We describe a novel mutation in the gene coding for protein kinase C gamma (PRKCG) in patients of a German family affected with slowly progressive gait ataxia, dysarthria, and nystagmus. The G/T missense mutation occurred in exon 2 of PRKCG and results in a substitution of glycine by valine (G63V) in the evolutionarily highly conserved cysteine-rich region 1/C1 domain of PRKCG. Among the 20 mutations described to date, this is the first mutation located in exon 2 of PRKCG. © 2006 Movement Disorder Society [source]

Farber's disease diagnosed by nerve biopsy

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2002
J. Jacobs
Introduction:, Farber's disease (granulomatosis) is a rare inherited lipid storage disease caused by a deficiency of lysosomal acid-ceramidase. Clinical features include contractures of limbs with swelling of joints and multiple subcutaneous nodules. In a few cases there is prominent involvement of central and peripheral nervous systems. Ceramide accumulates in the nodules and in cells of many other tissues including brain. Electron microscopy of affected cells shows membrane-bound inclusions, some of which have a highly characteristic curved or ,banana' shape (Farber bodies). Nerve biopsy findings have been described in a few cases but our patient appears to be the first to have been diagnosed by nerve biopsy. Case report:, This male infant presented at 6 months with joint pain and swelling, fever weakness and nystagmus: EMNG demonstrated sensory-motor polyneuropathy with features of demyelination. Semi-thin resin sections show a moderately reduced density of myelinated fibres. The myelin sheaths of most fibres are inappropriately thin, which was confirmed morphometrically: some axons are demyelinated. Vacuolar inclusions are seen in some Schwann cells. Teased fibres show de- and remyelination. Electron microscopy shows oval, boomerang- or banana-shaped inclusions in Schwann cells associated with myelinated and unmyelinated axons, but not in other cell types. Conclusion:, Farber's disease is associated with a demyelinating neuropathy. [source]

UNINTENTIONAL OVERDOSE WITH INTRATHECAL ZICONOTIDE

PAIN MEDICINE, Issue 2 2002
Article first published online: 4 JUL 200
Steven G. Charapata MD, Research Medical Center, Kansas City, MO; David Ellis MD, PhD, Elan Pharmaceuticals, South San Francisco, CA Ziconotide is a novel, N-type, voltage-sensitive calcium channel (VSCC) blocker, with well-documented efficacy as an intrathecal (IT) analgesic. Ziconotide has been administered to over 1000 chronic pain patients in nine clinical trials. Over 350 patients have been on ziconotide IT therapy for more than three months in a long-term safety and tolerability study. Common adverse events for ziconotide include dizziness, nausea, nystagmus, abnormal gait, constipation, urinary retention, somnolence, postural hypotension, vomiting, confusion and abnormal vision. Ziconotide adverse events are recognizable, reversible and manageable, by dose adjustment and slow dose titration. Case reports of unintentional overdose in six chronic pain patients treated with IT ziconotide are presented. These unintentional overdoses were attributable to pump programming or dilution errors; none were lethal. The patient who received the highest overdose was administered 31 mcg/hr over 24 hours, or nearly 750 mcg ziconotide, total. This hourly dose rate is 300-fold the current recommended initial dose rate of 0.1 mcg/hr. This patient was sedated, but arousable; vital signs were stable and patient had no change in blood pressure. His symptoms resolved within 24 hours. His Visual Analog Score of Pain Intensity (VASPI) was reduced from 82 at baseline to 2.5 at the end of the titration period. The patient elected to continue in the long-term IT ziconotide study. The other 5 cases of inadvertent overdose were less severe, with dose rate at 5 mcg/hr or less. Associated adverse events also resolved within 24-hours of discontinuing ziconotide infusion. Unlike an unintentional overdose with IT morphine, which slows respiration and could potentially lead to hypoxia, coma or death; ziconotide does not produce respiratory depression. No tolerance to the analgesic effect of ziconotide, or withdrawal symptoms after discontinuation of the drug have been reported. Ziconotide has a wide margin of safety as an IT analgesic. [source]

Life threatening medullary injury following adenoidectomy and local anesthetic infiltration of the operative bed

PEDIATRIC ANESTHESIA, Issue 2 2009
ELI HERSHMAN MD
Summary Objective:, To draw attention to a rare, life threatening complication of a rather common procedure, namely medullary injury following adenoidectomy and local anesthetic infiltration of the operative bed. Design:, Case report. Setting:, A tertiary pediatric critical care unit. Patient:, A healthy 7-year-old girl underwent adenoidectomy and local anesthetic infiltration of the adenoid bed with lidocaine and adrenaline. In the recovery room, nystagmus, dysarthria, dyspnea, inability to cough and right hemiparesis were noticed. Because of her inability to remove secretions tracheal intubation was performed, followed by severe, life threatening respiratory failure. Interventions:, Tracheal intubation, hemodynamic support, prolonged mechanical ventilation, nitric oxide, and tracheostomy. Conclusion:, In children, local anesthetic infiltration of the adenoid bed may cause life-threatening medullary injury and its routine use should be re-considered. [source]

Ventilation induced pneumothorax following resolved empyema

PEDIATRIC PULMONOLOGY, Issue 1 2008
A.G. Nyman MRCPCH
Abstract We report a case of pneumothorax as a result of positive pressure ventilation in a child previously treated for empyema. Three months following discharge for successful treatment of empyema our patient received a general anesthetic for an elective MRI of the brain for investigation of nystagmus. During recovery from the anesthetic he developed respiratory distress and was found to have a loculated pneumothorax. We propose that pleural fragility in childhood empyema possibly persists even after clinical resolution and in this case for up to 3 months. The complication of pneumothorax should be considered in all patients receiving positive pressure ventilation following resolved empyema. Pediatr Pulmonol. 2008; 43:99,101. © 2007 Wiley-Liss, Inc. [source]

Purely vertical upbeat nystagmus in bilateral posterior canal benign paroxysmal positional vertigo: A case report

THE LARYNGOSCOPE, Issue 1 2010
Jason A. Beyea MD
Abstract Vertical nystagmus occurs in patients with central vestibular system pathology. Lesions of the pons, medulla, and cerebellum lead to vertical nystagmus. Given this association, vertical nystagmus is considered pathognomonic in nature. We present a case of benign paroxysmal positional vertigo (BPPV) with positive Dix-Hallpike bilaterally, but also with upbeat purely vertical nystagmus in the straight back head hanging position. Computed tomography imaging of the typically pathologic structures in vertical nystagmus (brainstem/posterior fossa) revealed normal anatomy. We propose this case as an instance of peripheral-associated purely vertical nystagmus without central pathology, while building on our previous understanding of BPPV physiology. Laryngoscope, 2010 [source]

Response to Galvanic Vestibular Stimulation in Patients with Unilateral Vestibular Loss

THE LARYNGOSCOPE, Issue 1 2006
Hyun Jik Kim MD
Abstract Objectives: This study sought to characterize various responses to galvanic vestibular stimulation (GVS) by comparing GVS-induced eye movements in healthy subjects and patients with vestibular function loss. The study also aimed to estimate the clinical significance of GVS tests. Finally, an effort was made to localize the primary excitation site of stimulation in the vestibular system. Materials and Methods: Three parameters of response to GVS, spontaneous nystagmus, galvanic stimulating nystagmus (GSN), and postgalvanic stimulating nystagmus (PGSN), were evaluated in 20 normal subjects and 14 patients with complete unilateral vestibular function loss resulting from labyrinthectomy or vestibular neurectomy using a three-dimensional video-electronystagmography technique. Results: In normal subjects, GSN was detected in all subjects and was directed toward the negative electrode. PGSN was also detected but was directed toward the opposite electrode. When the negative electrode was attached to the intact side in unilateral vestibular loss subjects, GSN was always directed toward the negative electrode and PGSN was never observed. When the negative electrode was attached to the lesion side, however, GSN was detected in only one case, and PGSN was observed and directed to the intact side in 13 patients. Conclusions: The response to GVS in vestibular loss patients differed from that in normal subjects, which suggests that GVS could be useful for estimating the extent of vestibular function loss. The fact that the patterns of GVS response differed so significantly suggests that the primary site of excitation is not central but is instead the peripheral vestibular organ. [source]

Relationship of Static and Dynamic Mechanisms in Vestibuloocular Reflex Compensation,

THE LARYNGOSCOPE, Issue 2 2005
FACS, Shawn D. Newlands MD
Abstract Objectives/Hypothesis: We tested the hypothesis that recovery of dynamic oculomotor behavior (specifically the vestibuloocular reflex [VOR]) after a unilateral labyrinthectomy (UL) is independent from static deficit recovery (e.g., spontaneous nystagmus). This hypothesis predicts that VOR recovery from peripheral vestibular lesions that do not cause static symptoms, such as unilateral semicircular canal plugging (UCP), would have a similar time course and magnitude as recovery from a lesion that creates both a static and dynamic imbalance, such as UL. Furthermore, animals compensated after UCP would be expected to retain their compensated VOR response after the additional insult of ipsilateral labyrinthectomy. Study Design: An experimental study in the Mongolian gerbil animal model. Methods: The horizontal VOR was measured from both eyes using infrared video-oculography on gerbils before and after UCP, UL, or ipsilateral labyrinthectomy after a previous UCP. Eye movements were recorded during yaw rotation in the dark. Results: UL resulted in a more severe acute deficit than the UCP. Over several weeks, the UCP animals compensated their horizontal VOR, particularly on rotation toward the intact side, quicker and more completely than the UL animals. Animals that underwent ipsilateral labyrinthectomy 8 to 11 weeks after UCP demonstrated preservation of the improved gain, particularly on rotation toward the intact labyrinth. However, the difference between the UL groups with or without precedent UCP was not retained after 72 hours, and long-term compensation was poorest in the UL after UCP group. Conclusions: Plasticity in dynamic vestibular reflexes induced by UCP is preserved after a subsequent UL. However, neurologic events during the first and second day after UL appear to limit, change, or suppress the long-term dynamic compensation of the VOR, regardless of whether the animal had a previous UCP. [source]

Ventilation Time of the Middle Ear in Otitis Media With Effusion (OME) After CO2 Laser Myringotomy

THE LARYNGOSCOPE, Issue 4 2002
Benedikt Sedlmaier MD
Abstract Objective The aim of this study was to investigate the transtympanic ventilation time, the healing course of the tympanic membrane, the early and late complications, and the recurrence rate of otitis media with effusion (OME) within 6 months after CO2 laser myringotomy with the CO2 laser otoscope Otoscan. Study Design Prospective clinical study. Materials and Methods In this study, laser myringotomy was performed with the CO2 laser otoscope Otoscan in a patient population comprising 81 children (159 ears) with a history of otitis media with effusion (OME) associated with adenoidal and sometimes tonsillar hyperplasia. The procedure on the tympanic membrane was accordingly combined with an adenoidectomy, a CO2 laser tonsillotomy, or a tonsillectomy and therefore performed under insufflation anesthesia. In all ears, approximately 2 mm circular perforations were created in the lower anterior quadrants with a power of 12 to 15 W, a pulse duration of 180 msec, and a scanned area of 2.2 mm in diameter. Results None of the children showed postoperative impairment of cochleovestibular function such as sensorineural hearing loss or nystagmus. Otomicroscopic and videoendoscopic monitoring documented the closure time and healing pattern of tympanic membrane perforations. The mean closure time was found to be 16.35 days (minimum, 8 days; maximum, 34 days). As a rule, an onion-skin-like membrane of keratinized material was seen in the former myringotomy perforations at the time of closure. At the follow-up 6 months later, the condition of the tympanic membrane of 129 ears (81.1%) could be checked by otomicroscopy and videoendoscopy and the hearing ability by audiometry and tympanometry. The CO2 laser myringotomy sites appeared normal and irritation-free. Two of the tympanic membranes examined (1.6%) showed atrophic scar formation, and 1 (0.8%) had a perforation with a diameter of 0.3 mm. The perforation was seen closed in a control otoscopy 15 months postoperatively. OME recurred in 26.3% of the ears seen intraoperatively with mucous secretion (n = 38) and in 13.5% of the ears with serous secretion (n = 37;P <.05). Conclusion The most important principle in treating OME is ventilation of the tympanic cavity. CO2 laser myringotomy achieves this through a self-healing perforation in which its diameter roughly determines the duration of transtympanic ventilation. Laser myringotomy competes with ventilation tube insertion in the treatment of OME. It may be a useful alternative in the surgical management of secretory otitis media. [source]