Patients: Five hundred ten individuals from 8 hospitals that met the American Academy of Otolaryngology-Head and Neck Surgery diagnostic criteria for definitive Ménière's disease. Intervention: Conservative treatment. Main Outcome Measure: Frequency and duration of episodes of definitive vertigo during follow-up. Results: Ménière's disease affects both sexes and both ears equally, with onset generally in the fourth decade

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The introduction of transcranial magnetic stimulation has allowed the study of conduction in the proximal portions and central pathways of the cranial nerves. A study is made of cranial nerve XII with transcranial magnetic stimulation at two levels, cortical and cisternal, registering the motor evoked potential by means of surface electrodes in contact with the upper face of the tongue. Motor evoked potentials were constantly observed on cortical stimulation, in a painless, easy, and reproducible way, with mean values of 10.84 +/- 1.14 milliseconds (latency) and 7.81 +/- 1.14 mV (amplitude). Motor evoked potentials were unconstant and showed reduced amplitudes on cisternal stimulation, with mean values of 4.72 +/- 0.62 milliseconds and 0.83 +/- 1.26 mV. The magnetic stimulation technique allows the study of the entire motor pathway of cranial nerve XII (motor cortex-medulla, motoneuron-muscle). The method is efficient, noninvasive, painless, and easily reproduced, and it comes close to being an ideal clinical conduction study technique for this cranial nerve.

An experimental model is described for recording laryngeal evoked potentials at the brainstem level through electrical stimulation of the superior laryngeal nerve. Rabbits were divided into two groups according to age: Group 1 consisted of 20 adults (over 6 months old), while group 2 was comprised of 1‐month‐old rabbits. Under general anesthesia, the superior laryngeal nerve was electrically stimulated and the corresponding evoked potentials were recorded by needle electrodes placed close to the dorsal and ventral aspects of the brain stem. Clear age‐related differences were observed for latency, amplitude, and morphology of the potentials. This fact suggests postnatal maturation of the nerve structures, both peripheral and central. Sectioning the superior laryngeal nerve abolished all responses. Adduction of both vocal cords was observed in conjunction with the use of stimulation.

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