Cochlear hydrops (or cochlear Menieres or cochlear endolymphatic hydrops) is a condition of the inner ear involving a pathological increase of fluid affecting the cochlea. This results in swelling that can lead to hearing loss or changes in hearing perception. It is a form of endolymphatic hydrops and related to Menieres disease. Cochlear hydrops refers to a case of inner-ear hydrops that only involves auditory symptoms and does not cause vestibular issues. Cause and behavior
Cochlear hydrops refers to an increase in endolymphatic fluid in the inner ear. This build-up is either due to an overproduction or insufficient drainage of endolymph in the constant regulation of fluid in the inner ear. Usually, only one ear is affected. The root cause of the process is unclear and may vary from patient to patient, but can have auto-immune, viral, and/or allergic triggers, among others.The build-up of endolymph creates pressure in the scala media. This causes its diameter to increase, and the vestibular membrane to curve outwards in the direction of the vestibule. The changes to the membrane can result in changes to either the hearing perception or hearing threshold of a patient.Episodes are usually cyclical and symptoms fluctuate through time. Patients may be symptom-free between episodes, which themselves may progressively worsen, improve, or remain constant in severity or duration.
Depression or anxiety that the condition will worsen or progress to Menieres disease.As with Menieres disease, atypical, early, or mild cases may only present some symptoms. Diagnosis
Diagnosis is based on symptoms and a hearing test that documents a loss in the low and mid frequencies, usually only in one ear. For patients with mild or atypical hydrops, the hearing thresholds may be normal, but they may experience a subjective, unilateral distortion of sounds in lower frequencies, such as diplacusis or that voices are sounding "robotic". Patients may also mention a feeling of pressure or fullness in the ear.To objectively test for the presence of hydrops, an electrocochleography (or ECOG) procedure can be done to detect elevated inner ear pressure. It is also possible to reveal the presence of hydrops with an MRI.If vertigo is experienced, the diagnosis progresses to Menieres disease. This occurs if the fluid increase leads to a leak or rupture of the membranes in the inner ear, causing a mixture of perilymph and endolymph. Treatment
Treatment for cochlear hydrops is the same as for Menieres disease. Currently, no cure exists for either.If a patient has undergone sudden sensorineural hearing loss, a course of steroids is often prescribed in an attempt to recover the hearing. Steroids may be injected directly through the eardrum.Like Menieres Disease, a low salt diet is recommended as a preventative measure. A diuretic may be prescribed to help lower salt content.Betahistine is the most widely prescribed medication for the treatment of Menieres disease.