Extended phenotype and clinical subgroups in unilateral Meniere disease: A cross-sectional study with cluster analysis.

OBJECTIVES: To define clinical subgroups by cluster analysis in patients with unilateral Meniere disease (MD) and to compare them with the clinical subgroups found in bilateral MD. DESIGN: A cross-sectional study with a two-step cluster analysis. SETTINGS: A tertiary referral multicenter study. PARTICIPANTS: Nine hundred and eighty-eight adult patients with unilateral MD. MAIN OUTCOME MEASURES: best predictors to define clinical subgroups with potential different aetiologies. RESULTS: We established five clusters in unilateral MD. Group 1 is the most frequently found, includes 53% of patients, and it is defined as the sporadic, classic MD without migraine and without autoimmune disorder (AD). Group 2 is found in 8% of patients, and it is defined by hearing loss, which antedates the vertigo episodes by months or years (delayed MD), without migraine or AD in most of cases. Group 3 involves 13% of patients, and it is considered familial MD, while group 4, which includes 15% of patients, is linked to the presence of migraine in all cases. Group 5 is found in 11% of patients and is defined by a comorbid AD. We found significant differences in the distribution of AD in clusters 3, 4 and 5 between patients with uni- and bilateral MD. CONCLUSIONS: Cluster analysis defines clinical subgroups in MD, and it extends the phenotype beyond audiovestibular symptoms. This classification will help to improve the phenotyping in MD and facilitate the selection of patients for randomised clinical trials.

Menière's disease.

Menière's disease (MD) is a chronic multifactorial disorder of the inner ear characterized by episodic vestibular symptoms associated with sensorineural hearing loss, tinnitus, and aural pressure. Epidemiologic and genomic evidence supports a genetic susceptibility with multiple biochemical pathways involved, including the endocrine system, innate immune response, and autonomic nervous system. Allergens, infectious agents, vascular events, or genetic factors could modify inner-ear homeostasis and trigger MD. The diagnosis of MD is based on clinical criteria and requires the observation of an episodic vertigo syndrome associated with low- to medium-frequency sensorineural hearing loss and fluctuating aural symptoms (hearing loss, tinnitus, and/or fullness) in the affected ear. Headache is also found during the attacks and bilateral involvement is found in 25-40% of cases. Audiologic and vestibular assessment is recommended to monitor the clinical course. The treatment of MD is symptomatic to obtain relief of vestibular episodes and preventive to limit hearing loss progression. Treatment options include sodium restriction, betahistine, intratympanic gentamicin, or steroids and eventually surgery, such as cochlear implantation.

Caracterización de las alteraciones vestibulares en pacientes con síndrome de latigazo cervical / Vestibular disorders in patients with whiplash injury syndrome

Objetivo: Determinar la prevalencia de alteraciones vestibulares en pacientes con síndrome de latigazo cervical (SLC). Material y método: Estudio transversal en 24 pacientes consecutivos atendidos por presentar SLC con grado II o III de la Quebec Task Force y tiempo de evolución menor de seis meses. Se realizó exploración clínica vestibular completa y exploración instrumental con videonistagmografía (VNG), incluyendo prueba calórica bitérmica, registro de potenciales evocados miogénicos vestibulares (VEMPs), prueba de la vertical visual subjetiva (VVS) y posturografía dinámica. También fueron evaluados mediante los cuestionarios SF-36 (salud general), DHI-S (discapacidad vestibular) y SIMS (simulación). Resultados: La prevalencia de alteraciones vestibulares se situó en el 25%. El reflejo vestíbulo-cólico evaluado mediante VEMPs estaba alterado en el 25% de los pacientes con SLC. La VSV se encontraba alterada en el 17% de los casos. La posturografía dinámica identificó un patrón vestibular en el 25% de los casos. La estimación de simulación entre los pacientes con SLC se produjo, al menos, en el 25% de los casos. Conclusión: La alteración de varias pruebas vestibulares en pacientes con SLC sugiere una disfunción vestibular asociada a ILT prolongada. Las puntuaciones elevadas en los cuestionarios de discapacidad vestibular (DHI) y de simulación de síntomas (SIMS) podrían ser utilizadas como indicadores de percepción de trastorno vestibular grave e ILT prolongada (AU)

Objective: To determine the prevalence of vestibular dysfunction in patients with whiplash. Material and method: A cross-sectional study including 24 consecutive patients with grade II or III whiplash according to the Quebec Task Force scale and time course < 6 months. A complete vestibular examination with video-oculographic recording was performed including a bithermal caloric test, vestibular evoked myogenic potentials (VEMPs), subjective visual vertical (SVV) and dynamic posturography. We also used the questionnaires SF-36 (general health), DHI-S (vestibular handicap) and SIMS (malingering). Results: The prevalence of vestibular dysfunction is around 25%. The vestibulo-collic reflex evaluated by VEMPs was absent in 25% of patients with whiplash. SVV was abnormal in 17% of cases. Dynamic posturography showed a vestibular pattern in 25% of cases. Scores suggesting malingering in whiplash was observed in 25% of cases. Conclusion: The finding of several abnormal tests in patients with whiplash suggests a vestibular dysfunction associated with a long incapacity. High scores in the DHI and SIMS scales could be useful as predictors of severe vestibular disorder with long incapacity (AU)

Familial clustering and genetic heterogeneity in Meniere's disease.

The aims of this study were to estimate the prevalence of familial cases in patients with Meniere's disease (MD) and to identify clinical differences between sporadic and familial MD. We recruited 1375 patients with definite MD according to the American Academy of Otolaryngology-Head and Neck Surgery criteria, obtaining the familial history of hearing loss or episodic vertigo by direct interview or a postal survey in 1245 cases in a multicenter study. Familial clustering was estimated by the recurrence risk ratio in siblings (λs ) and offspring (λo ) using intermediate and high prevalence values for MD in European population. A total of 431 patients (34%) reported a familial history of hearing loss or recurrent vertigo and 133 patients had a relative with possible MD. After clinical reevaluation, 93 relatives in 76 families were diagnosed of definite MD (8.4%), including three pairs of monozygotic twins. λs and λo were 16-48 and 4-12, respectively. We observed genetic heterogeneity, but most families had an autosomal dominant inheritance with anticipation. No clinical differences were found between sporadic and familial MD, except for an early onset in familial cases. We may conclude that MD has a strong familial aggregation and that sporadic and familial MDs are clinically identical.

[Errors in computerized electronystagmography]. / Errores en la electronistagmografía computarizada.

Computerized electronystagmography (ENG) is the analysis of the eye movement recordings using a computer program to identify nystagmus and quantitate response parameters. The results of 100 consecutive bithermal caloric tests of patients complaining of peripheral vertigo were analyzed by computer. All computer analyses were reviewed by authors and either were deemed accurate as made by the computer or were corrected manually. Final test interpretations with and without manual intervention were compared. In 48 tests the computer analysis was not modified. In 20 tests canal paresis and directional preponderance changed after manual review, but not the final diagnosis. In the remaining 20 tests, manual review yielded a different final diagnosis. Computerized ENG provides rapid and accurate vestibular studies, but recordings should be reviewed because system algorithms sometimes identify other ocular movements as nystagmus.

[Anomalous visual suppression of caloric nystagmus]. / Supresión visual anómala del nistagmus calórico.

In patients with central vestibular disorders it is often seen an anomaly of the nystagmus (either spontaneous or provoked) presenting as a defectuous (or non existing at all) reduction of its intensity, when the glance is fixed in a spot. We report 6 cases with this finding. Detailed clinical records, complete vestibular tests and other ancilliary studies as well, allowing to pinpoint the diagnosis, are set forth. The faulty or anomalous visual suppression is not an uniform response, because three several forms through the electronystagmographic tracins could be checked. One in which visual fixation does not affect at any the course of the nystagmic response, a second in which there is a significative reduction of the studied parameter but clearly pathologic, and the third one in which only with visual fixation nystagmus was seen. We consider that this finding indicates the existence of a central disorder, once sedative drugs are ruled out and the practice of the ENG was realized in good conditions of alertness of the patient.

[Intraoperative facial nerve monitoring: results]. / Monitorización facial intraoperatoria. Resultados.

Intraoperative facial nerve monitoring is performed by electromyographic recording of motor action potentials generated by facial nerve stimulation or mechanical damage of the facial nerve, and helps the surgeon to localize the course of this nerve, reduce the possibility of its injury during surgery, and assure its anatomical and functional integrity. We report our experience on the intraoperative facial nerve monitoring in 35 patients, ten of which belong to absolute indications for monitoring, and to relative indications the remaining cases. In every case, we used the Nerve Integrity Monitor (NIM-2), manufactured by Xomed. Assessment of facial nerve integrity degree is performed pre- and postoperatively using the House-Brackmann classification. We only found in two cases (5.7%) some degree of palsy in the late postoperative period. No correlation was found between the recorded intraoperative response and the functional results in the early postoperative period.