| [Objective]Studying the effect of hyperbaric oxygen to cochlear deafness and its clinical meaning by researching 60 guinea pigs which had toxic deafness induced by gentamicin. [Method] Guinea pigs were injected with gentamicin to their abdominal cavity. The dosage is 150mg/kg, one time a day and it needed 5 days. Guinea pigs inhaled the hyperbaric oxygen 2ATA(atmosphere absolute) immediately for 130 minutes and were treated differently for 1 day,10 days and 20 days. At the same time guinea pigs were exposed respectively to commonbaric air(CBA) and hyperbaric air(HBA) for 1 day, 10 days and 20 days in control. The auditive brain response(ABR) were measured after injection and exposure. The cochlear blood flow( CBF) were measured and the pathology changes of cochlear hair cells were observed, [result] The threshold shift (db) of guinea pigs exposured to HBO was 48. 3333±3. 8925(set of 1 day), 55. 8333 ± 10. 1876(set of 10 days) and 53. 3333±10. 5169 (set of 20 days) respectively. The CBA groop was 51. 6667±4. 4381 (set of 1 day), 50. 8333±7. 5252(set of 10 days) and 53. 3333±7. 7850 (set of 20 days) respondingly. The HBA groop was 53. 7500± 4. 3301 (set of 1 day), 51. 6667±4. 4381 (set of ten days) and 54.1667±5.1493 (set of 20 days) respondingly. The difference of threshold shift among the 3 groop had no significant meaning( P>0. 05), and the difference of threshold shift had nomeaning ( P>0.05) before and after the exposure. The cochlear blood flow(MV) of guinea pigs exposed to HBO was 37.3467 ± 0. 9024 (set of 1 day) , 37. 2333 ±2. 1836 (set of 10 days) and 38. 2467 ±2. 7700(set of 20 days) respectively. That of the groop CBA was 31. 2733±1.6655(set of 1 day),^ 29. 9483 ± 1. 2512 (set of 10 days) and 30. 4833±1. 7046(set of 20 days) respectively. The HBA groop was 30. 3900±1. 3773(set of 1 day), 29. 3933±0. 7018(set of 10 days) and 28. 9400±0. 9855 (set of 20 days) respectively. The difference among them had significant meaning( P<0. 01). Scanning electron microscope of cochlear hair cells showed that the main damage to 1 day groop was in outer hair cell of bottom return .The swelling, degeneration, scattering abscission in many outer hair cells were obversed. Inner hair cell was normal on the whole. The damage to 10 days groop involved the second and third return, and the bottom return was damaged heavily. Many outer hair cells necrosed and abscised. Inner hair cell became scatter, lodging and conglutinated to fusion glomeration. The second and three return were damaged lightly and the outer hair cell became swelled , degenerated, and part of them necrosed and losed. 20 days groop' s damage was more heavy and had already involved in the needle return. Most of the hair cells and pillar cells in bottom return and second return died and became reticulum shape scar. The outer hair cells of the third and forth return necrosed partly. The remaining cells became shortness, disorder and lodging. Compared with the groop of CBA and the groop of HBA, the damage to hair cells of groop HBO were not obversed obvious improvement. There were not reborn phenomenon in the hair cells. [Conelusion] The simple therapy of HBO can increase the CBF of guinea pigs with toxic deafness induced by gentamicin at theshort term. But it has no obvious effect to auditory amelioration and improvement and the recovery of form and the function of cochlear hair cells. The long-term influence and complex therapy need further study.
|
PDF Full Text Request