Endolymphatic sac decompression has probably polarized the otolaryngology community more so than any other aspect of MD treatment. Following the publication of the Danish Sham study, 18 the procedure was largely abandoned in Europe. However, the study had methodological flaws leading many to question the validity of the results. The procedure remains popular in the United States at the present time. To do justice to this particular argument is well beyond the scope of this article. However, being Irish, I shall invoke an anecdote on the subject involving the consumption of alcohol. After a night with this author and another otolaryngologist of Polish extraction, one of the authors of the Danish Sham study conceded that the procedure might actually be effective in controlling vertigo symptoms. However, he felt that the improvement, rather than being mediated via decompression of the endolymphatic sac, was due to the surgery inflicting a degree of insult to the vestibular system, similar to the effect of low-dose gentamicin. I suspect that heated discussion on the subject of sac decompression will continue for some years to come.
The dura mater and the mastoid or craniotomy are then closed with a variety of materials, and the patient is observed in the intensive care unit. Because the balance fibers are cut suddenly, the surgery causes intense vertigo and imbalance for a few days requiring supportive medical care, medications for nausea and eventually physical therapy. A cane or walker may be needed for a while, depending on the patient’s health and activity level prior to the surgery. Once the patient is able to ambulate safely, he may be discharged home, but vestibular and balance therapy is continued on an out-patient basis to speed the patient’s recovery as much as possible. A return to full function occurs in most patients, although many do feel imbalanced when tired or stressed.
The injections are performed with the patient lying down and using the office microscope. The ear is first cleaned of wax. A small area of the eardrum is numbed with a drop of medication. A small needle and syringe are then used and the needle is passed through the eardrum at the site that is numbed so that the tip is in the ear, near the round window. This is a membrane where drugs are absorbed in to the cochlea. The fluid is injected in to the middle ear and the patient stays lying down for 20-30 minutes during which he does not swallow or sniff. The drug sits against the round window and is absorbed in to the inner ear. The patient then sits up slowly and leaves the office. Patients should not drive for a few hours after this procedure. Water is kept out of the ear until it is confirmed that the tiny hole has healed.