Objective-To investigate the clinical features and natural history of mal de debarquement (MdD).Design-Retrospective case review with follow-up questionnaire and telephone interviews. Setting-University Neurotology Clinic.Patients-Patients seen between 1980 and 2006 who developed a persistent sensation of rocking or swaying for at least 3 days after exposure to passive motion.Main outcome measure-Clinical features, diagnostic testing, and questionnaire responses.Results-Of 64 patients (75 % women) identified with MdD, 34 completed follow-up questionnaires and interviews in 2006. Most patients had normal neurological exams, ENGs and brain MRIs. The average age of the first MdD episode was 39 ± 13 years. A total of 206 episodes were experienced by 64 patients. Of these, 104 episodes (51 %) lasted > 1 month; 18 %, > 1 year; 15 %, > 2 years; 12 %, > 4 years, and 11 %, > 5 years. Eighteen patients (28 %) subsequently developed spontaneous episodes of MdD-like symptoms after the initial MdD episode. There was a much higher rate of migraine in patients who went on to develop spontaneous episodes (73 %) than in those who did not (22 %). Subsequent episodes were longer than earlier ones in most patients who had multiple episodes. Re-exposure to passive motion temporarily decreased symptoms in most patients (66 %). Subjective intolerance to visual motion increased (10 % to 66 %) but self-motion sensitivity did not (37 % to 50 %) with onset of MdD.Conclusion-The majority of MdD episodes lasting longer than 3 days resolve in less than one year but the probability of resolution declines each year. Many patients experience multiple MdD episodes. Some patients develop spontaneous episodes after the initial motion-triggered episode with migraine being a risk factor.

In this review, we provide a description of the recent methods used for immunohistochemical staining of the human inner ear using formalin-fixed frozen, paraffin and celloidin-embedded sections. We also show the application of these immunohistochemical methods in auditory and vestibular endorgans microdissected from the human temporal bone. We compare the advantages and disadvantages of immunohistochemistry (IHC) in the different types of embedding media. IHC in frozen and paraffin-embedded sections yields a robust immunoreactive signal. Both frozen and paraffin sections would be the best alternative in the case where celloidin-embedding technique is not available. IHC in whole endorgans yields excellent results and can be used when desiring to detect regional variations of protein expression in the sensory epithelia. One advantage of microdissection is that the tissue is processed immediately and IHC can be made within 1 week of temporal bone collection. A second advantage of microdissection is the excellent preservation of both morphology and antigenicity. Using celloidin-embedded inner ear sections, we were able to detect several antigens by IHC and immunofluorescence using antigen retrieval methods. These techniques, previously applied only in animal models, allow for the study of numerous important proteins expressed in the human temporal bone potentially opening up a new field for future human inner ear research.

We report the immunolocalization of aquaporins (AQPs) 1, 4, and 6 in the human auditory and vestibular endorgans. A rapid protocol was applied to audiovestibular endorgans microdissected from postmortem human temporal bones from six subjects (ages ranging from 75 to 97 years) with no history of audiovestibular disease. Temporal bones were fixed in formalin, and the endorgans were immediately microdissected. Cryostat sections were obtained from audiovestibular endorgans and were subjected to double-immunohistochemical staining with antibodies against AQPs and several cellular markers. In the human cochlea, AQP1 immunoreactivity was localized to the fibrocytes of the spiral ligament and the sub-basilar tympanic cells; AQP4 immunoreactivity was localized to the outer sulcus cells, Hensen's cells, and Claudius' cells; AQP6 immunoreactivity was localized to the apical portion of interdental cells in the spiral limbus. In the vestibular endorgans (macula utriculi and cristae), AQP1 was localized to fibrocytes and blood vessels of the underlying stroma and trabecular perilymphatic tissue; AQP4 immunoreactivity was localized to the basal pole of vestibular supporting cells; AQP6 was localized to the apical portion of vestibular supporting cells. Cochlear and vestibular hair cells and nerve fibers were not immunoreactive for any AQP. Supporting cells were identified with antibodies against glial fibrilar acidic protein. Nerve fibers and terminals were identified with antibodies against neurofilaments and Na(+)K(+)ATPase. The high degree of conservation of AQP expression in the human inner ear suggests that AQPs play a critical role in inner ear water homeostasis.

Increased cochlea/medulla ratio indicates increased blood-labyrinth barrier permeability in Menière disease compared with idiopathic sudden sensorineural hearing loss. Increased cochlea/medulla ratio in asymptomatic ears of patients with Menière disease also suggests an underlying systemic cause of Menière disease and may provide a pathophysiologic biomarker.

Age of onset of episodic vertigo or fluctuating hearing loss was significantly lower in patients with MMD (mean +/- 1.96*SE = 37.2 +/- 6.3 years) than in those with MD (mean +/- 1.96*SE = 49.3 +/- 4.4 years). Concurrent bilateral aural symptoms and hearing loss were seen in 56% of MMD and 4% of MD patients. A family history of episodic vertigo was seen in 39% of MMD and 2% of MD patients.