Characterization of Vestibular Perception in Patients with Persistent Postural-Perceptual Dizziness.

Objective: To assess vestibular (i.e., passive self-motion) perception in patients diagnosed with persistent postural-perceptual dizziness (PPPD).

A possible link between intracranial lipomas and localization-related relapses in multiple sclerosis.

Intracranial lipomas are congenital malformations representing less than 0.5% of intracranial tumors. They are found incidentally and are asymptomatic in the majority of patients.

Polymorphisms of the HTR1a allele are linked to frontal brain electrical asymmetry.

Polymorphic variations in genes related to serotonin synthesis, transport, recognition, or degradation may convey subtle changes in serotonin system architecture that may place an individual at risk for psychopathology when faced with life stressors. The relationship between three key serotonin alleles and frontal brain electrical asymmetry, a putative endophenotype of depression, was examined. Risk alleles were hypothesized to predict relatively greater right frontal brain activity regardless of current clinical state.

Functional interactions between FOXC1 and PITX2 underlie the sensitivity to FOXC1 gene dose in Axenfeld-Rieger syndrome and anterior segment dysgenesis.

Axenfeld-Rieger ocular dysgenesis is associated with mutations of the human PITX2 and FOXC1 genes, which encode transcription factors of the homeodomain and forkhead types, respectively. We have identified a functional link between FOXC1 and PITX2 which we propose underpins the similar Axenfeld-Rieger phenotype caused by mutations of these genes. FOXC1 and PITX2A physically interact, and this interaction requires crucial functional domains on both proteins: the C-terminal activation domain of FOXC1 and the homeodomain of PITX2.

Diagnosis and management of lateral semicircular canal benign paroxysmal positional vertigo.

Objective: Describe the diagnosis, treatment, and outcome of a group of 20 patients with lateral semicircular canal benign paroxysmal positional vertigo (LSC-BPPV).

Study Design And Setting: Retrospective review of 20 patients with LSC-BPPV (10 with geotropic and 10 with apogeotropic nystagmus) presenting to a tertiary balance center. Diagnosis was confirmed with infrared nystagmography in Dix-Hallpike positioning tests and supine positional tests.

Canalith repositioning for benign paroxysmal positional vertigo.

Objective: To evaluate the efficacy of canalith repositioning maneuvers (Semont, Epley, and modified maneuvers) in the treatment of posterior canal benign paroxysmal positional vertigo (BPPV) in comparison to the rate of resolution in the untreated control cohort.

Data Sources: Source articles were identified by a MEDLINE search of English language sources before 2004 plus manual crosschecks of bibliographies from identified articles, selected national meeting abstracts, review article references, and textbook chapters.

Study Selection: Each controlled trial that compared canalith repositioning patients to untreated control subjects in posterior canal benign positional vertigo (blinded and unblinded) was reviewed for inclusion.

Fluid-structural dynamics of ground-based and microgravity caloric tests.

Microgravity caloric tests aboard the 1983 SpaceLab1 mission produced nystagmus results with an intensity comparable to those elicited during post- and pre- flight tests, thus contradicting the basic premise of Barany's convection hypothesis for caloric stimulation. In this work, we present a dynamic fluid structural analysis of the caloric stimulation of the lateral semicircular canal based on two simultaneous driving forces for the endolymphatic flow: natural convection driven by the temperature-dependent density variation in the bulk fluid and expansive convection caused by direct volumetric displacement of the endolymph during the thermal irrigation. Direct numerical simulations indicate that on earth, the natural convection mechanism is dominant.

Effect of gravity on the caloric stimulation of the inner ear.

Robert Barany won the 1914 Nobel Prize in medicine for his convection hypothesis for caloric stimulation. Microgravity caloric tests aboard the 1983 SpaceLab 1 mission produced nystagmus results that contradicted the basic premise of Barany's convection theory. In this paper, we present a fluid structural analysis of the caloric stimulation of the lateral semicircular canal.

Lateral sinus thrombosis associated with zoster sine herpete.

Herpes zoster results from reactivation of the varicella zoster virus (VZV). Zoster sine herpete (ZSH) is an uncommon manifestation of VZV infection and presents with similar symptoms but without the vesicular rash. We describe an unusual case of lateral sinus thrombosis (LST) that developed during the clinical course of ZSH in the C2 distribution.

Benign paroxysmal positional vertigo: a clinician's perspective.

The pathogenesis and epidemiology of benign paroxysmal positional vertigo are still not well defined. Treatment protocols have emerged along with complementary hypotheses regarding pathogenesis. Ultrastructural studies suggest a multistep process of otoconia metabolism responsible for forming the otolith membrane.

Application of multivariate statistics to vestibular testing: discriminating between Menière's disease and migraine associated dizziness.

Menière's disease (MD) and migraine associated dizziness (MAD) are two disorders that can have similar symptomatologies, but differ vastly in treatment. Vestibular testing is sometimes used to help differentiate between these disorders, but the inefficiency of a human interpreter analyzing a multitude of variables independently decreases its utility. Our hypothesis was that we could objectively discriminate between patients with MD and those with MAD using select variables from the vestibular test battery.

Chronic cervical myofascial pain syndrome: Improvement in dizziness and pain with a multidisciplinary rehabilitation program. A pilot study.

Purpose: The purpose of this retrospective, pilot study was to assess changes in dizziness, pain and function in subjects undergoing an outpatient rehabilitation program focusing on cervical pain.

Methods: Fifteen subjects with chronic cervical myofascial pain and concurrent dizziness of suspected cervical origin completed a retrospective questionnaire. Improvement in pain, dizziness and function were recorded on a visual analog scale (VAS) in response to a non-standardized rehabilitation program involving modalities, stretching, strengthening, trigger point injections and aerobic conditioning.

Intratympanic gentamicin for treatment of intractable Meniere's disease: a preliminary report.

Topical administration of aminoglycoside antibiotics in the middle ear can achieve "chemical labyrinthectomy" in patients with intractable Meniere's disease. Herein we report our results of intratympanic gentamicin therapy in 21 patients using two different dosing protocols, twice weekly and twice daily (b.i.

Classification of human rotation test results using parametric modeling and multivariate statistics.

The usefulness of vestibular testing is directly related to the accuracy of the test interpretations. Two factors, subjective analysis of large test data sets and failure to make appropriate age corrections, tend to reduce test accuracy. Correction of these problems can be accomplished by application of physiologically based models of vestibular function and multivariate classification techniques to the test data, thereby creating a more objective test interpretation procedure.

Vestibular function test anomalies in patients with chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) is distinguished by the new onset of debilitating fatigue that lasts at least 6 months, concomitant with other symptoms to be described later. Many CFS patients complain of disequilibrium, yet the exact type of the balance dysfunction and its function and its location (peripheral vs. central) have not been described.

Randomized clinical trials in single patients during a 2-year period.

Objective: To describe the feasibility of a single patient trial (SPT) service and study the influence of formal SPTs on therapeutic precision.

Design: Descriptive and evaluate study of SPTs. All planned trials were double-blind, randomized, multiple crossover trials.

Visual-vestibular interaction in humans during active and passive, vertical head movement.

We studied visual-vestibular interaction (VVI) in 9 normal human subjects using active and passive vertical head rotations. Gain and phase of the vertical vestibulo-ocular reflex (VOR) and visually enhanced vestibulo-ocular reflex (VVOR) were measured for single frequency sinusoidal motion, as well as for sinusoidal motion of continuously increasing frequency, over the range of 0.4 to 4.

Vertigo and the anterior inferior cerebellar artery syndrome.

We present two patients with clinical features of infarction in the distribution of the anterior inferior cerebellar artery (AICA) who had vertigo as an isolated symptom for several months prior to infarction. Both had risk factors for cerebrovascular disease and other episodes of transient neurologic symptoms not associated with vertigo. At the time of infarction they developed vertigo, unilateral hearing loss, tinnitus, facial numbness, and hemiataxia.