Carol A. Foster

Familial migraine with vertigo and essential tremor

We report a family with dominantly inherited migraine headaches, episodic vertigo, and essential tremor.All symptoms improved with the use of acetazolamide. Linkage analysis ruled out linkage to markers on chromosome 19p, known to be linked to the genetic defect in families with the clinically similar syndromes of hemiplegic migraine and periodic ataxia. This genetic heterogeneity of migraine syndromes could result from defects in a family of genes coding proteins with similar properties. NEUROLOGY 1996;46: 458-460

Endolymphatic hydrops in Ménière's disease: cause, consequence, or epiphenomenon?

Objective To determine the relationship of endolymphatic hydrops to Ménière’s disease. Data Sources Comprehensive review of articles from 1938 through 2012 via Medline and Index Medicus. Study Selection Articles discussing Ménière’s disease and/or endolymphatic hydrops that include temporal bone autopsy data. Data Extraction Fifty-three case reports and series were studied containing examination of 541 hydropic temporal bones and including 276 patients with Ménière’s disease. These were divided into those meeting the 1995 American Academy of Otolaryngology–Head and Neck Surgery criteria for Ménière’s disease and those that failed to meet these criteria. Conclusion An individual meeting the 1995 criteria for Ménière’s disease has a near certain probability of having endolymphatic hydrops in at least 1 ear. Autopsy data do not support the view that the association of MD and EH is an epiphenomenon or that MD causes EH; this leaves us with the probability that EH causes MD. If it is causative, hydrops alone is insufficient to cause Ménière’s disease, indicating that there must be one or more additional cofactors that cause asymptomatic hydrops to become symptomatic Ménière’s disease. Vascular risk factors should be studied as possible cofactors.

Meniere's disease

Menieres disease (MD) is a disorder of the inner ear that causes vertigo attacks, fluctuating hearing loss, tinnitus and aural fullness. The aetiology of MD is multifactorial. A characteristic sign of MD is endolymphatic hydrops (EH), a disorder in which excessive endolymph accumulates in the inner ear and causes damage to the ganglion cells. In most patients, the clinical symptoms of MD present after considerable accumulation of endolymph has occurred. However, some patients develop symptoms in the early stages of EH. The reason for the variability in the symptomatology is unknown and the relationship between EH and the clinical symptoms of MD requires further study. The diagnosis of MD is based on clinical symptoms but can be complemented with functional inner ear tests, including audiometry, vestibular-evoked myogenic potential testing, caloric testing, electrocochleography or head impulse tests. MRI has been optimized to directly visualize EH in the cochlea, vestibule and semicircular canals, and its use is shifting from the research setting to the clinic. The management of MD is mainly aimed at the relief of acute attacks of vertigo and the prevention of recurrent attacks. Therapeutic options are based on empirical evidence and include the management of risk factors and a conservative approach as the first line of treatment. When medical treatment is unable to suppress vertigo attacks, intratympanic gentamicin therapy or endolymphatic sac decompression surgery is usually considered. This Primer covers the pathophysiology, symptomatology, diagnosis, management, quality of life and prevention of MD.

Deficits of gaze stability in multiple axes following unilateral vestibular lesions

Abstract Abnormalities in the vestibulo-ocular reflex (VOR) after unilateral vestibular injury may cause symptomatic gaze instability. We compared five subjects who had unilateral vestibular lesions with normal control subjects. Gaze stability and VOR gain were measured in three axes using scleral magnetic search coils, in light and darkness, testing different planes of rotation (yaw and pitch), types of stimulus (sinusoids from 0.8 to 2.4 Hz, and transient accelerations) and methods of rotation (active and passive). Eye velocity during horizontal tests reached saturation during high-velocity/acceleration ipsilesional rotation. Rapid vertical head movements triggered anomalous torsional rotation of the eyes. Gaze instability was present even during active rotation in the light, resulting in oscillopsia. These abnormal VOR responses are a consequence of saturating nonlinearities, which limit the usefulness of frequency-domain analysis of rotational test data in describing these lesions.

Functional loss of the horizontal doll's eye reflex following unilateral vestibular lesions

The dolls eye reflex represents the vestibulo‐ocular reflex (VOR) elicited by high‐acceleration head rotation. After complete unilateral vestibular lesions, the ipsilateral, horizontal dolls eye reflex is replaced by a series of “catch‐up” saccades. These cause permanent symptoms of blurred vision and dizziness during ipsilateral turns. We compared normal controls and patients with complete surgical lesions or canal paresis of up to 9 years duration via electronystagmography (ENG) to determine the usefulness of the dolls eye test as a diagnostic test for complete vestibular lesions. This test was found to be more sensitive in diagnosis of such lesions than head‐shaking nystagmus, rotatory directional preponderance, and spontaneous nystagmus. It is also useful to document VOR function in patients in whom caloric irrigation is contraindicated.

Canal conversion and reentry: a risk of Dix-Hallpike during canalith repositioning procedures.

Objective To determine the incidence, cause, and prevention of horizontal canal benign paroxysmal positional vertigo (H-BPPV) and reentry into the common crus during canalith repositioning procedures (CRPs). Study Design Prospective case series. Setting Academic tertiary referral center. Patients Forty-four patients with symptomatic posterior canalithiasis (P-BPPV) confirmed on Dix-Hallpike. Intervention Up to 5 CRP for initial P-BPPV and additional maneuvers for canal conversion or reentry in 1 session. Main Outcome Measures Incidence and timing of onset of H-BPPV or common crus reentry and the outcome of treatment maneuvers. Results H-BPPV or reentry occurred during the Dix-Hallpike after a canal-clearing CRP and affected 16% (7/44) of subjects. Approximately 87% (7/8) of reentry or conversion events occurred after the very first CRP. Geotropic H-BPPV occurred in 9% (4/44) overall but in 13% (4/30) whose P-BPPV was resolved by a single CRP. All were cleared with H-BPPV maneuvers, 3 of 4 resolving with a single Gufoni maneuver. Approximately 9% (4/44) of patients developed reentry of particles into the common crus. It was treated by raising the patient to the upright position. By waiting 15 minutes after treatment of reentry, a final normal Dix-Hallpike was obtained without causing reentry into any canal in all patients. Conclusion If the first CRP clears the posterior canal, there is an elevated risk of reentry or canal conversion if another Dix-Hallpike is performed immediately. These complications can be treated by additional maneuvers; if unfamiliar with these techniques, the risk can be reduced by waiting at least 15 minutes between repetitions of CRP.

Noonan's syndrome with sensorineural hearing loss and vestibular abnormalities:

508 Noonan’s syndrome (NS) is a common association of multiple congenital anomalies involving the face, ears, and heart,1 with an estimated incidence of 1:1000 to 2500 live births. It is usually transmitted as autosomal dominant, with a recent linkage to chromosome 12.2 Penetrance is highly variable, with some family members showing only a few stigmata of the condition. Patients were previously described as having Turner phenotype with a normal karyotype. Features that can be recognized on otolaryngologic examination are illustrated in Fig. 1. Diagnosis can be complicated by changes in facial phenotype with aging, but auricular abnormalities are persistent. The ears are usually low-set and posteriorly rotated with a thickened helix and are often protuberant. Hearing loss is common.3 Only one audiogram has been published, and no reports including extensive audiologic testing have appeared. Nystagmus has been reported,4 although no studies have documented vestibular function. Additional diagnostic physical findings and comparison with other syndromes are given in Table 1. We present a case of NS diagnosed in adulthood with progressive bilateral loss of hearing and vestibular function, associated with gaze-evoked nystagmus and other central abnormalities. These findings were documented on audiologic and vestibular testing.

Optimal management of Ménière's disease.

Confusion in the nomenclature of Ménière’s disease and lack of a standard definition of the disorder until 1995 has hampered accurate assessment of treatment efficacy since the presently defined disorder was first described in 1938. The lack of a widely accepted mechanism of the disease has also delayed the development of rational treatments. Past treatments have focused on relieving elevated pressures in the hydropic ear and more recently on treatment of underlying migraine. Present dietary methods of control include sodium restriction and migraine trigger elimination. Pharmacologic treatments include diuretics, migraine prophylactic medications, histamine analogs, and oral steroids. Surgical procedures include intratympanic steroid perfusion, shunts, and ablative procedures when conservative treatments fail. External pressure devices are also used. Evidence of efficacy is lacking for most interventions other than ablation. At our institution, Ménière’s disease is treated as a cerebrovascular disorder. Control of risk factors for cerebrovascular ischemia is combined with treatment of pressure dysfunction in the hydropic ear. Screening for risk factors is performed at presentation. Migraine, dyslipidemia, obesity, diabetes, sleep apnea, hypertension, and atherosclerosis are among the major factors that often require medical management. Migraine prophylactic medications, magnesium supplementation, sodium restriction, migraine trigger elimination, diuretics, anticoagulants, and antihypertensives are among the treatments used initially. Steroids administered orally or intratympanically are used if control is not achieved medically, and ablation remains the definitive treatment in unilateral cases experiencing treatment failure.

Comparison of caloric reactivity between migraineurs and non-migraineurs.

OBJECTIVE To demonstrate that the elevated prevalence of migraine in patients with vertigo disorders is due to enhanced sensitivity to dizziness, which could cause migraineurs to seek more, or earlier, medical care for vertigo disorders, confounding the ability to show causation. METHODS This case-control study investigated whether migraineurs perceive dizziness more intensely than non-migraineurs by comparing caloric responses in migraineurs, non-migraineurs and possible migraineurs. The summed caloric responses in the best responding ear were reviewed. RESULTS The migraine group had higher caloric response values, with a mean of 37.97 degrees per second, which was statistically significant when compared to the values for the possible migraine group (30.74 degrees per second (p < 0.05)) and the non-migraine group (30.70 degrees per second (p < 0.001)). CONCLUSION The findings suggest that migraineurs experience vestibular stimuli more intensely compared to non-migraineurs, which might explain the association of migraine with vestibular disorders in general.

A Comparison of Two Home Exercises for Benign Positional Vertigo: Half Somersault versus Epley Maneuver

Benign paroxysmal positional vertigo (BPPV) frequently recurs after treatment, so a home exercise would be desirable. We designed a self-administered exercise, the half somersault, for home use. In this randomized single-blind study, we compare the efficacy of our exercise to self-administered Epley maneuvers in patients with BPPV. Subjects performed exercises twice while observed, were re-tested with the Dix Hallpike, and then reported on exercise use for 6 months. Outcome measures were the reduction of nystagmus intensity, tolerability of induced dizziness, and long-term efficacy. Both exercises resulted in a significant reduction in nystagmus after two self-applications. The Epley maneuver was significantly more efficacious in reducing nystagmus initially, but caused significantly more dizziness during application than the half somersault. During the 6-month follow-up, the Epley group had significantly more treatment failures than the half somersault group. We believe that both exercises can be self-applied to control symptoms, but the half somersault is tolerated better and has fewer side effects as a home exercise.