Other studies related to Audiology
Some controlled trials concerning 1100 patients in 8 publications were performed, a mojority of which were in Germany. After ineffective conservative treatement including plasmaexpander such as Hydroxyaethylstarch or others, normovolaemic haemodilution, cortisone and oral haemo-rheological substances, HBOT is effective in 50% of the cases to reduce hearing loss by 20 dB or more. Approximatley 11% have a complete recovery. All authors confirm better results with earlier onset of HBOT.
A randomized prospective trial of primary HBOT versus primary conservative treatment in Germany shows a better outcome in the HBOT group with substantial recovery in 80% of the patients. Another controlled prospective trial including patients after ineffective conservative treatment including cortisone shows substantial improvement in more than 30% of the cases even if the delay was more than 3 months.
Evaluations of 7766 patients in 13 publications show reduction of molestation and intensity of Tinnitus by 50% in around 70% of the cases if treated within 3 months of the onset. Around 30% lose their Tinnitus completely. Chronic tinnitus with duration of more than 3 months or bilateral manifestation shows improvement rates of 50% and around 30% of the cases after ineffective conservative treatment.
Based on 1200 cases of acoustic trauma – partially evaluated in prospective studies Pilgramm states that the best results by HBOT in combination with Haes. Because of 50% spontaneos remission within the first 48 hours HBOT should start immediately the third day after trauma. If hyperbaric oxygenation is begun later, the effectiveness decreases rapidly.