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Ménière's disease ,〔''(Dictionary.com Unabridged )'' (v 1.1). Random House, Inc. Accessed on 9 September 2008〕 also called endolymphatic hydrops, is a disorder of the inner ear that can affect hearing and balance. It is characterized by episodes of vertigo, tinnitus, and hearing loss. The hearing loss comes and goes for some time, alternating between ears, then becomes permanent. The condition is named after the French physician Prosper Menière, who, in an 1861 article, first reported that vertigo was caused by inner ear disorders.〔Méniere (1861) ("Sur une forme de surdité grave dépendant d’une lésion de l’oreille interne" ) (On a form of severe deafness dependent on a lesion of the inner ear), ''Bulletin de l'Académie impériale de médecine'', 26 : 241.〕 The condition affects people differently; it can range in intensity from being a mild annoyance to a lifelong condition. ==Signs and symptoms== Ménière's often begins with one symptom, and gradually progresses. However, not all symptoms must be present to confirm the diagnosis although several symptoms at once is more conclusive than different symptoms at separate times.〔(【引用サイトリンク】title=Meniérè's disease )〕 Other conditions can present themselves with Ménière's-like symptoms, such as syphilis, Cogan's syndrome, autoimmune inner ear disease, dysautonomia, perilymph fistula, multiple sclerosis, acoustic neuroma, and both hypo- and hyperthyroidism.〔Haybach, pg. 55〕 Ménière's symptoms vary. Not all sufferers experience the same symptoms. However, so-called "classic" Ménière's has the following four symptoms: * Attacks of rotational vertigo that can be severe, incapacitating, unpredictable, and last anywhere from minutes to hours,〔Haybach, pg. 70〕 but generally no longer than 24 hours. For some, prolonged attacks can occur, lasting from several days to several weeks, often severely incapacitating the sufferer. This combines with an increase in volume of tinnitus and temporary, albeit significant, hearing loss. Hearing may improve after an attack, but often becomes progressively worse. Nausea, vomiting, and sweating sometimes accompany vertigo, but are symptoms of vertigo, and not of Ménière's.〔Haybach, p. 72〕 * Fluctuating, progressive, unilateral (in one ear) or bilateral (in both ears) hearing loss, usually in lower frequencies.〔Haybach, p. 71〕 For some, sounds can appear tinny or distorted, and patients can experience unusual sensitivity to noises.〔Haybach, pg. 79〕 * Unilateral or bilateral tinnitus. * A sensation of fullness or pressure in one or both ears. Some patients may have parasympathetic symptoms, which aren't necessarily symptoms of Ménière's, but rather side effects of other symptoms. These include nausea, vomiting, and sweating—which are typically symptoms of vertigo, and not of Ménière's. Vertigo may induce nystagmus, or uncontrollable rhythmical and jerky eye movements, usually in the horizontal plane, reflecting the essential role of non-visual balance in coordinating eye movements.〔Haybach, pg. 46〕 Sudden falls without loss of consciousness (drop attacks, also known as Tumarkin attacks) may be experienced by some people, usually in the later stages of the disease. Less than 10% of people with Ménière's disease tend to experience such attacks. There is typically a sensation of being pushed sharply to the floor from behind (this is thought to be triggered by a sudden mechanical disturbance of the otolithic membrane that activates motoneurons in the vestibulospinal tract). The affected person is able to get up again immediately afterwards.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ménière's disease」の詳細全文を読む スポンサード リンク
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