Correlations between vertigo, weather fronts, cold temperatures, and low pressures with episodes of Meniere's disease have been previously reported earlier. Such previous reports have indicated that sudden changes in pressure in the inner ear because of weather fronts are a leading causative factor of Meniere's disease. The insertion of a ventilation tube into the eardrum is a recognized method of maintaining a pressure equilibrium in the middle ear. Although the usefulness of this tube has been questioned, it seems to be an acceptable option when choosing between conservative therapy and invasive treatment. Cochlear symptoms and vertigo improve under a relatively positive pressure in the middle ear when patients with Meniere's disease are placed in a decompression chamber. Therefore, a new device that sends micro-pressure pulses into the ear (e.g., the Meniett® device) has become available in western countries. Because this device has not yet been approved in Japan, eardrum massage machines are expected to be used as an alternative method for the treatment of Meniere's disease.
The diagnosis of Ménière's disease is primarily based on the clinical symptoms of vertigo attacks and hearing loss, which usually fluctuates. Historically, several different diagnostic criteria have been proposed by: 1) The Japanese Ménière's disease study group in 1974 and 2008; 2) The Japan Society for Equilibrium Research in 1987; 3) The American Academy of Otolaryngology-Head and Neck Surgery in 1995; and 4) The Bárány Society also proposed diagnostic criteria for Ménière's disease in 2015. In order to address the future direction for the diagnosis, treatment of and research into Ménière's disease, it is crucial to comprehensively understand how these criteria describe the symptoms and background etiology of Ménière's disease. For example, the exact definitions of the term “vertigo” are different among these criteria. In the Japanese criteria, “vertigo” is not restricted to a rotating sensation of the body, whereas the American criteria define vertigo of the Ménière's type as rotational vertigo. In the Japanese criteria, hearing loss temporally coincides with the vertigo attacks, whereas the American and Bárány Society's criteria do not have such restrictions. Along with the current advances in diagnostic tests for otologic diseases, Bárány Society's criteria include an updated list of the differential diagnosis for Ménière's disease. Most importantly, the Japanese criteria and the American criteria strongly support the hypothesis that the etiology of Ménière's disease is endolymphatic hydrops. In the Bárány Society's criteria, the pathogenesis includes not only the endolymphatic hydrops but other conditions as well. It is important to understand the concordance and differences of these criteria of Ménière's disease.
The oculomotor signs resulting from lesions affecting specific cerebellar regions have not yet been precisely defined in humans. The purpose of this study was therefore to analyze findings of electronystagmography (ENG) quantitatively in a patient with a posterior fossa meningioma mainly compressing the posterior vermis. A-70-year-old woman had often experienced a paroxysmal positional dizziness (or a faint sensation) on raising her head from prone position or on turning round, accompanied with no auditory symptoms with recent onset. Such dizziness usually resolved in a moment even though the provoking position was maintained. At our outpatient clinic, no induced nystagmus was observed by positioning or positional changing tests. MRI disclosed a meningioma approximately 2 cm in diameter to the left of the midline at the posterior fossa. The tumor seemed to compress the surface of the cerebellar vermis, mainly the culmen (Lobulus-V) and declive (VI). The other parts of the vestibular-cerebellum (such as flocculus, nodulus or uvula) and the brainstem were apparently not affected. The characteristic findings of the ENG were as follows: (1) lateral beating nystagmus (rightwards>leftwards) in the dark; (2) rebound nystagmus; (3) impairment of vertical smooth pursuit, while the horizontal pursuit was preserved; (4) upbeating nystagmus mainly during shifting eyes rightward or upward in the dark; (5) abnormal eye movements such as double saccadic pulses or ocular flutter were frequently intermingled both in the light and dark; (6) The peak slow phase velocity of OKN was mildly reduced, while frequencies of the slow phase velocity of OKN were preserved; (7) the left OKAN was within normal limits, while the right OKAN (slow phase was left) was not so inhibited and prolonged; and (8) vestibular caloric nystagmus was well induced bilaterally. Both sides of visual suppression of the caloric nystagmus were well preserved. Among these findings, it would be presumed that (3), (4) and (5) were especially ascribed in the present case to compression of the cerebellar vermis by the tumor, though the definite pathophysiological mechanism has not yet been clarified.
Distinguishing between inner ear decompression sickness and a perilymphatic fistula is difficult in cases of vertigo after diving. In case of inner ear decompression sickness, it is necessary to immediately perform recompression treatment; however, hyperbaric oxygen is a contraindication in cases of a perilymphatic fistula, in cases of which it is furthermore necessary to rapidly perform an exploratory tympanotomy. Therefore, the differential diagnosis between inner ear decompression sickness and perilymphatic fistula is important to distinguish in divers with vertigo. For accurate diagnosis, it is necessary to carefully obtain the history and check for barotrauma by otoscopy and for any pneumolabyrinth by computed tomography examination of the temporal bone. If a diagnosis cannot be determined, bilateral paracentesis should be performed before recompression treatment. Cochlin-tomoprotein is expected to be a marker for diagnosing a perilymphatic fistula and if rapid diagnosis of these can be achieved in the future, it will be useful for distinguishing between inner ear decompression sickness and perilymphatic fistula. We hope to establish normative guidelines for diagnosis and treatment of vertigo after diving.
In Japan there are few reports of vestibular rehabilitation for patients with dizziness being provided by physical therapists compared to other countries around the world. One of the most frequently used outcome measures for vestibular rehabilitation is the Dizziness Handicap Inventory (DHI) which is divided into 3 categories; physical, emotional and functional and consists of 25 questions. There are many reports that the total score of the DHI is used for evaluating outcomes, however, there are few reports about analyzing the individualized questions of the DHI. The purpose of this study was to investigate the effectiveness of vestibular rehabilitation for patients with dizziness using the DHI, and to analyze the individualized questions of the DHI after vestibular rehabilitation. Twenty-six patients who had suffered from dizziness for more than 3 months participated in this study. Postural stability and Japanese-DHI (J-DHI) were measured before and after 3 months of vestibular rehabilitation. The results showed that there were significant differences in postural stability and total scores of the J-DHI before and after vestibular rehabilitation. Five of nine J-DHI questions pertaining to physical activity and quick head movements did not improve; however, the J-DHI total score did improve. The results of this study indicate that vestibular rehabilitation may not be effective for physical activity and quick head movements. The exact amount of physical activity and quick head movements were not evaluated in this study and should be in future investigations.