Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Humanos , Nimodipina/uso terapéutico , Pérdida Auditiva Súbita/tratamiento farmacológico , Glucocorticoides , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Esteroides/uso terapéutico , Resultado del Tratamiento , Estudios Retrospectivos , Audiometría de Tonos Puros , DexametasonaRESUMEN
OBJECTIVE: To evaluate the treatment outcomes of nimodipine and steroid combination therapy for idiopathic sudden sensorineural hearing loss (ISSNHL). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Seventy-eight patients who were diagnosed with ISSNHL were divided into two group based on the treatment strategies used: steroid+nimodipine (SN, nâ=â36) and steroid only (SO, nâ=â42) groups. Based on the level of hearing loss before treatment, subgroup analysis (<90âdB HL, SN-S versus SO-S groups; ≥90âdB HL, SN-P versus SO-P groups) was performed. INTERVENTIONS: Nimodipine+dexamethasone versus dexamethasone alone. MAIN OUTCOME MEASURES: Hearing thresholds and complete/partial recovery rate after treatment. RESULTS: Hearing thresholds after treatment were not significantly different between the SN and SO groups (46.8â±â29.4 versus 54.8â±â27.6âdB HL, pâ=â0.218). However, the complete recovery rate was significantly higher in the SN group than in the SO group (41.7% versus 16.8%, pâ=â0.014). In subgroup analysis, the complete recovery rate was significantly higher in the SN-S group than in the SO-S group (60.9% versus 19.2%, pâ=â0.003), whereas the difference between the SN-P and SO-P groups was not significant (7.7% versus 12.5%, pâ=â0.672). The cumulative incidence of complete recovery was significantly higher in SN-S group than in the SO-S group (pâ=â0.005); the mean recovery time was 4.4 weeks (95% confidence interval [CI], 2.8-6.1) in the SN-S group and 8.8 weeks (95% CI, 7.0-10.5) in the SO-S group. CONCLUSIONS: The results of this study suggest that nimodipine and steroid combination therapy for ISSNHL results in a higher complete recovery rate than steroid alone in patients with moderate to severe hearing loss.
Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Audiometría de Tonos Puros , Dexametasona/uso terapéutico , Glucocorticoides/uso terapéutico , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Súbita/tratamiento farmacológico , Humanos , Nimodipina/uso terapéutico , Estudios Retrospectivos , Esteroides/uso terapéutico , Resultado del TratamientoRESUMEN
Saposin B (Sap B) is an essential activator protein for arylsulfatase A in the hydrolysis of sulfatide, a lipid component of myelin. To study Sap B's role in hearing and balance, a Sap B-deficient (B(-/-)) mouse was evaluated. At both light and electron microscopy (EM) levels, inclusion body accumulation was seen in satellite cells surrounding spiral ganglion (SG) neurons from postnatal month 1 onward, progressing into large vacuoles preceding satellite cell degeneration, and followed by SG degeneration. EM also revealed reduced or absent myelin sheaths in SG neurons from postnatal month 8 onwards. Hearing loss was initially seen at postnatal month 6 and progressed thereafter for frequency-specific stimuli, whereas click responses became abnormal from postnatal month 13 onward. The progressive hearing loss correlated with the accumulation of inclusion bodies in the satellite cells and their subsequent degeneration. Outer hair cell numbers and efferent function measures (distortion product otoacoustic emissions and contralateral suppression) were normal in the B(-/-) mice throughout this period. Alcian blue staining of SGs demonstrated that these inclusion bodies corresponded to sulfatide accumulation. In contrast, changes in the vestibular system were much milder, but caused severe physiologic deficits. These results demonstrate that loss of Sap B function leads to progressive sulfatide accumulation in satellite cells surrounding the SG neurons, leading to satellite cell degeneration and subsequent SG degeneration with a resultant loss of hearing. Relative sparing of the efferent auditory and vestibular neurons suggests that alternate glycosphingolipid metabolic pathways predominate in these other systems.