[Multi-center clinical study on the treatment of the low-middle frequency sudden hearing loss].

OBJECTIVE: To investigate and compare the short-term outcome of patients with low-middle frequency sudden deafness treated with alone or combination treatment. METHODS: From August 2007 to October 2011, 205 patients with the diagnosis of low-middle frequency sudden deafness who were from 33 different clinical centers were recruited. All patients were followed up for four weeks from the initial examination. Patients were treated with steroid , Ginaton, batroxobin respectively, or Ginaton and steroid combination treatment. RESULTS: The total effective rate was 90.73%. In Ginaton group, the total effective rate was 87.27%, 89.19% in steroid group, 87.80% in batroxobin group, and 95.83% in Ginaton and steroid group. Considering the total effective rate, there was no statistical difference between four groups (χ(2) = 7.98, P = 0.54). The clinical cure rate for steroid alone was 81.01%, Ginaton alone 76.36%, batroxobin alone 68.29%, and Ginaton and steroid combination treatment 80.56%. There were no clinically significant differences between the different treatments (P > 0.05). CONCLUSIONS: The low-middle frequency sudden deafness tends to have a relatively favorable prognosis. The steroid played a good effect in the treatment. But different treatments either improving the microcirculation of inner ear or alleviating edema blood has undifferentiated results. Therefore the combination therapy may be more effective.

[Effect of postaurical subcutaneously injection of triamcinolone acetonide for subjective tinnitus].

OBJECTIVE: To determine whether postaurical subcutaneous injection of triamcinolone acetonide is effective for subjective tinnitus refractory to medical treatment. METHODS: A total of 100 adult patients with subjective tinnitus of cochlear origin were randomly assigned to receive postaurical subcutaneous.Injection of either triamcinolone acetonide (n = 50) or saline solution (n = 50). The treatment protocol comprised 5 injections, one per week for 5 weeks.Improvement was measured by tinnitus severity evaluation index evaluation scale, at baseline and one week after the last injection. The follow-up period was 6 months. RESULTS: No significant difference existed between two groups regarding age, gender, pure tone average, pretreatment tinnitus intensity, tinnitus duration or hearing loss level tinnitus duration (P = 0.316,0.685,0.839,0.682 and 0.881 respectively).No significant post-treatment changes in the tinnitus severity index (experimental group = 52%, control group = 44%) were observed in either group (P = 0.724). The most frequently encountered side effect was pain during injection. CONCLUSION: The postaurical subcutaneous injection of triamcinolone acetonide has no obvious benefit compared with placebo for subjective tinnitus of cochlear origin refractory to medical treatment.

[Protection from noise-induced hearing loss by a nitric oxide synthase inhibitor and neurotrophin 3 in the guinea pig cochlea].

OBJECTIVE: To observe the protective effect of nitric oxide synthase inhibitor-N(G)-nitro-L-arginine methyl ester (L-NAME) with or without neurotrophin 3 (NT3) on hearing in acoustic trauma. METHODS: Eighty pigmented male guinea pigs were randomly divided into two groups: sham-exposed group (n=20) and noise-exposed group. The latter was divided into three subgroups: saline group (n=20), L-NAME group (n=20) and L-NAME + NT3 group (n=20). Two days consecutively and 30 min before noise exposure (4 kHz octave band noise at 115 dB SPL for 5 h), subjects in L-NAME and L-NAME + NT3 groups received an intraperitoneal injection of 10 mg/kg; animals in saline group received the same dosage of physiological saline at the same time. Four days before noise exposure, NT3 in artificial perilymph was delivered to the right scala tympani via a mini-osmotic pump in noise + L-NAME + NT3 group. Auditory brainstem responses (ABR) were measured before and 10 days following noise exposure. The cochlear tissue was assayed for nitric oxide (NO) level 3 days after noise exposure. Protection was assessed physiologically by the change in ABR threshold shift, and histologically by outer hair cell (OHC) survival. RESULTS: The hearing thresholds and the number of OHC were relatively stable in sham-exposed group. The obvious threshold shift and OHC loss were observed in the noise-exposed groups. The hearing thresholds, NO level of cochlear tissue and OHC loss in the noise + saline group were significantly higher than those in the noise + L-NAME group (P < 0.01) and noise + L-NAME + NT3 group (P < 0.01). NT3 provided an additive functional (P < 0.01), but not morphological protection with L-NAME (P = 0.095). CONCLUSION: Compared to L-NAME alone, a combination of L-NAME and NT-3 can provide an additional protection against acoustic trauma in the guinea pig cochlear.

[Changes in antioxidant capacity of the guinea pig exposed to noise and the protective effect of alpha-lipoic acid against acoustic trauma].

The study was aimed at exploring the effect of noise on total antioxidant capacity (TAC) in serum, nitric oxide (NO) level in the cochlea and the protective action of alpha-lipoic acid against noise-induced hearing loss (NIHL). Sixty guinea pigs (350-400 g) were divided randomly into three groups (control group, noise+saline group and noise+alpha-lipoic acid group). Serum and cochlear tissue were treated immediately after noise exposure (4-kHz octave band, 115 dB SPL 5 h) to determine the level of TAC and NO, respectively. Auditory brainstem responses (ABRs) were measured before and immediately after exposure. The threshold of hearing in the control group was relatively stable, while the hearing threshold in the noise+saline group was significantly higher than those in the noise+alpha-lipoic acid group (P<0.05). TAC level of the noise+saline group was significantly lower than that of the control group P<0.05 . TAC level of the noise+alpha-lipoic acid group was significantly higher than that of the noise+saline group P<0.05 , while there was no significant difference in the levels between the noise+alpha-lipoic acid group and the control group (P>0.05). The NO level of the cochlear tissue in the noise+saline group was significantly higher than that of the control group (P<0.05). Cochlear NO level in the noise+alpha-lipoic acid group was significantly lower than that of the noise+saline group (P<0.05), while there was no significant difference in cochlear NO levels between the noise+alpha-lipoic acid group and the control group (P>0.05). The results obtained indicate that noise exposure causes a decrease in serum TAC and an increase in NO in cochlea. alpha-Lipoid acid exerts a protective effect against hearing loss in acoustic trauma through its antioxidant effects.