Acoustic Neuroma and Meniere’s Disease both affect the inner ear, causing similar symptoms of vertigo--a sensation of spinning, even when still--and gradual hearing loss. The symptoms arise from different causes and doctors must make an accurate diagnosis to distinguish between the two conditions in order to treat the patient correctly.
Meniere’s Disease
Meniere’s disease occurs due to an increase in the volume or pressure of the endolymph, the fluid in the membranous labyrinth of the inner ear. Normally, movement of the endolymph signals that the head is moving, and it helps a person to retain spatial awareness and balance. When the volume or pressure rises, the brain constantly receives false signals about movement, leaving the patient dizzy. The increased pressure slowly damages the inner ear, leading to permanent hearing loss.
Acoustic Neuroma
Acoustic neuroma, also known as a vestibular Schwannoma, means a tumor on the insulating cells of the vestibular nerve that carries sound signals from the inner ear to the brain. The tumor grows slowly, and is not cancerous, but it can disrupt both hearing and balance. Rarely, according to the Mayo Clinic, large tumors can press on the brain with life-threatening consequences.
Similarities
Acoustic neuroma and Meniere’s disease both cause episodes of vertigo and tinnitus, an annoying ringing or buzzing in the ears. Both conditions also gradually rob the patient of hearing. Acoustic neuroma and Meniere’s disease most commonly affect people 30 to 60 years old.
Differences
According to the NIDCD, asymmetry is a key feature of acoustic neuroma. In most cases the tumor occurs on one side and causes symptoms only on that side. In addition to their other symptoms, people with large acoustic neuromas that press on the nerves of the face experience facial numbness on the same side as the tumor. Hearing loss is gradual and never improves. In rare cases, acoustic neuroma causes a sudden hearing loss.
In Meniere’s disease, loss of hearing occurs in episodes along with vertigo and a feeling of pressure in the ears. Hearing recovers between episodes, through gradually there is some permanent loss. Episodes of vertigo are long-lasting--at least 20 minutes--and intense with Meniere’s disease, sometimes leading to nausea and diarrhea, or causing the patient to fall.
Diagnosis
To definitively diagnose an acoustic neuroma rather than Meniere’s disease, a doctor might order a CT scan or an MRI to see the tumor. In patients with tinnitus, a feeling of pressure in the ears, and at least two episodes of vertigo lasting at least 20 minutes, a doctor diagnoses Meniere’s disease by exclusion after verifying hearing loss and ruling out a tumor with an MRI or CT scan.
Treatment
Patients with acoustic neuroma can wait and see how the tumor progresses, or undergo radiation or surgery to remove the tumor. There is no cure for Meniere’s disease, but patients can benefit from dietary changes, medications or surgery to control the vertigo.
