To define better the benefits and risks of intratympanic gentamicin in
jection treatment of intractable vertigo or drop attacks due to Menier
e's disease, we reviewed the charts of 18 patients whom we have now ob
served for >1 year after having completed this mode of therapy. There
were nine women and nine men aged 29-81 years; all had poor hearing in
the affected ear. Of the 18 patients, 14 have had no further vertigo
or drop attacks (11 patients after a single set of three to five injec
tions, another three after a further set of one to five injections). T
he treatment could be effective even if it did not abolish caloric res
ponses from the treated ear, even if it did not produce an acute vesti
bular deafferentation syndrome afterwards, and even after a failed ves
tibular nerve section. After treatment, five of the 18 patients develo
ped oscillopsia and ataxia-symptoms and signs of(presumably permanent)
chronic vestibular insufficiency; this proportion is not obviously lo
wer than that after vestibular neurectomy or surgical labyrinthectomy.
Of the 18 patients, 12 showed no change in the 1-kHz threshold and 13
showed no change in the 4-kHz threshold. When hearing did deteriorate
, the threshold rose by more than 30 dB at 1 Id-It in four patients an
d at 4 kHz in six patients. We conclude and confirm that intratympanic
gentamicin injections are a convenient and in most cases, effective a
nd safe treatment for intractable vertigo or drop attacks due to Menie
re's disease.