A pilot study comparing hearing thresholds of soldiers at induction and after completion of one year in high altitude area.

BACKGROUND: Despite so much research in high altitude area, our existing knowledge is still lacking on otological effects of long-term stay in high altitude. This pilot study was conducted to compare the hearing thresholds of army soldiers at induction and after completion of one year in high altitude area (HAA). METHODS: Hearing thresholds of 433 soldiers posted in HAA were recorded using pure tone audiometry at the time of induction and second thresholds after one year of stay in high altitude for frequencies of 500Hz, 1KHzs, 2 KHzs and 4 KHzs. The two sets of hearing thresholds for air conduction were compared using paired "t" test for any statistical significance. RESULTS: The mean Pure Tone Audiometry (PTA) thresholds for 433 left ears worsened from 9.43dB to 9.65dB at 500 HZs ; 14.02dB to 14.32dB at 1 KHZs ; 15.04dB to 16.09dB at 2KHzs and 18.63dB to 22.59dB at 4 KHZs. Similarly for right ear, PTA thresholds worsened from 9.43dB to 9.69dB at 500HZs; 13.95dB to 14.34dB at 1 KHZs; 15.38dB to 17.26dB at 2 KHZs and from 18.59dB to 23.06dB at 4KHZs. These results are found to be statistically significant (p<0.05) for all frequencies. CONCLUSION: This pilot study shows deterioration of hearing thresholds in tested frequencies in both ears after a long stay (one year) in high altitude area. We recommend further structured research on otologic effect of long term stay in high altitude.

Synthesis and Anticonvulsant Studies of Thiazolidinone and Azetidinone Derivatives from Indole Moiety.

2-Amino-5-(3'-indolomethylene)-1, 3 , 4 - oxadiazole (3): undergoes facile condensation with various aromatic aldehydes to gave 2-substitiuted arylidenylamino-5-(3'- indolomethylene) - 1, 3 , 4 - oxadiazole (4-8): . Cyclocondensation of (4-8): with thioglycolic acid and triethylamine yielded 3-[5'-(3"- indolomethylene)- 1', 3', 4'- oxadiazol-2'-yl]- 2- (substituted aryl)-4- thiazolidinones (9-13): and 1-[5'-(3"- indolomethylene) -1', 3', 4'- oxadiazol - 2'- yl ] -4-(substituted aryl) -2- azetidinones (14-18): . The structures of these compounds were established on the basis of analytical and spectral data. The newly synthesised compounds were evaluated for their anticonvulsant activity and acute toxicity.

Early Speech Perception Test Outcome in Children with Severe Sensorineural Hearing Loss with Unilateral Cochlear Implants Alone versus Bimodal Stimulation.

Bilateral stimulation of the auditory system has clear advantages over unilateral hearing. Hearing-impaired children are, therefore, generally fitted with hearing aids in both ears so that they can have the benefits of binaural hearing. Children who use acochlear implant in one ear and no acoustic stimulation in the opposite ear are at a definite disadvantage. This study was undertaken to determine the advantages of bimodal stimulation in pediatric population especially in terms of speech recognition. This study comprised of 30 children between 3 and 6 years of age with profound bilateral sensorineural hearing loss with cochlear implant in one ear and fitted with digital hearing aid in non-implanted ear. Speech recognition performance was compared in unilateral cochlear implant only and with bimodal hearing stimulation in the same set of children. A statistically significant difference was found between speech reception scores in children with a unilateral cochlear implant only and those with a cochlear implant in one ear and a hearing aid in the non implanted ear in quiet surroundings. It is suggested that the use of bimodal fitting be considered as an effective management method to obtain the advantage of binaural hearing in children who undergo unilateral cochlear implantation.

Impaired Vestibular Function After Cochlear Implantation in Children: Role of Static Posturography.

To identify vestibular dysfunction in children after cochlear implant surgery and to study the utility of static posturography in evaluating vestibular function in children. A prospective study was carried out on 25 children between 2 and 7 years of age with sensorineural hearing loss with no overt vestibular dysfunction. All children underwent static posturography using Synapsis Posturographic System (SPS) software (Version 3.0, REV C) using a static platform with foam. The centre of pressure (COP) shift was recorded as statokinesiogram on the software and the mean vestibular, visual and somesthetic scores were obtained. Cochlear implantation (CI) surgery was done with insertion of Med-El Pulsar standard cochlear implant with 12 twin electrodes. Children were evaluated again after 4 weeks of CI surgery (2 weeks after switch on) with static posturography on the same SPS software. The scores obtained were compared with pre op value and data analyzed statistically by paired t tests on SPSS 18 software. The mean age was 4.6 years with range 2-7 years. All the children in the study were able to complete the test with no difficulty and the mean time required for each child was 10.2 min. The mean pre op somesthetic score was 95.16 (SD 1.52) and post op score was 94.06 (SD 1.79). The mean pre op visual score was 86.64 (SD 2.24) and post op score was 82.55 (2.89). The mean pre op vestibular score was 84.11 (SD 2.20) and post op score was 73.66 (SD 4.25). Correlation and statistical analysis of the pre and post values of each score revealed statistically significant reduction in vestibular scores post CI. The vestibular system is at high risk of injury leading to vestibular dysfunction in children during CI. Our study found the static posturography as a simple, fast and efficient tool to screen children for vestibular dysfunction post CI. Identifying the dysfunction early can help in initiating early rehabilitation measures.