sodium bromate and potassium bromate are strong oxidants that are widely used in hair permanent wave neutralizers , reagents of printing or dyeing and other chemical processes .
hair wave permanent neutralizing solutions typically contain 2 - 10% sodium or potassium bromate , which are colorless , odorless and tasteless .
clinical manifestations of bromate intoxication include vomiting , diarrhea , central nervous system symptoms , oliguric or non - oliguric acute renal failure , hemolytic anemia , and deafness .
hearing impairment is rather common and is usually rapidly progressive , bilateral , and of severe to profound sensorineural type of hearing loss ( snhl ) .
although many investigators have studied the characteristics of hearing impairment , cochlear implantation ( ci ) after bromate intoxication has been rarely documented .
we hereby present a case of successful ci in bromate - induced bilateral sudden total deafness .
she had accidentally ingested a cold wave neutralizer . within one hour after the ingestion , she developed nausea , vomiting , and diffuse abdominal pain .
her past history included hypertension , left hemiparesis due to previous brain hemorrhage and infarction and depressive disorder . upon arrival in the emergency room of a local hospital , she received intravenous hydration and furosemide injection .
one day later , she was referred to our hospital with decreased urinary output and reduced mental state .
four days after admission , her kidney function was normalized and mentality was recovered to an alert state .
1b ) and v - wave was not detectable at 90 db in the auditory brainstem response .
she was diagnosed as having bromate - induced sudden deafness and steroid was administered systematically for a week with tapering for another week .
nucleus 24re was implanted without any intra - operative problems and the neural response telemetry showed satisfactory values .
six months after the implant , ci - aided pta showed a threshold of 30 db ( fig .
, she comprehended 70% of the sentences , 85% of the words and 68% in the korean version of the central institute for the deaf test .
hearing problems may be diagnosed with a delay after bromate intoxication due to other life - threatening symptoms such as acute renal failure which generally occurs within 1 hour after the ingestion . however , the onset of bromate - induced hearing loss is actually rapid , occurring within 4 - 16 hours of ingestion . like many other ototoxins ,
the degree of hearing impairment is severe to profound , and is irreversible in most cases .
since they are usually transient , loop diuretics including furosemide are ototoxic in themselves . in the present case , the patient received furosemide during the primary treatment , which may have aggravated the ototoxic effects of bromate .
previous studies using guinea pigs and sodium bromate demonstrated severe collapse of the reissner 's membrane , hair cell degeneration and damage of the stria vascularis .
the ototoxicity may be ascribed to a decrease in enzyme activities which leads to damage of the stria vascularis with degenerative changes in outer hair cells
on the other hand , dizziness associated with bromated - induced vestibulotoxicity is not common .
the dizziness could be secondary to other systemic toxicities such as lightheadedness or general malaise .
to our knowledge , there has only been one report in the english literature of ci performed in patients deafened due to bromated - ingestion . in this case , the diagnosis of hearing loss was delayed for at least 6 months after bromate ingestion . in our case ,
deafness was diagnosed right after the recovery of consciousness and the intervention with ci was done 3 months after the diagnosis . in both cases , the outcome of ci was good .
other potential drugs with ototoxicity should be avoided and early monitoring of hearing level is needed .
 despite the well - established nature of bromate - induced ototoxicity , cochlear implantation after bromate intoxication has been rarely documented . we hereby present a case of a 51-year - old female deafened completely after bromate ingestion . 
 her hearing was not restored by systemic steroid treatment and hearing aids were of no use . 
 a cochlear implantation was performed on her right ear 3 months after the bromate ingestion . in bromate intoxication cases , early monitoring of hearing level 
 is necessary and other drugs with potential ototoxicity should be avoided . 
 the outcome of cochlear implantation was excellent in this case of bromate - induced deafness . 
Introduction
Case Report
Discussion