Evaluation of intratympanic dexamethasone for treatment of refractory sudden sensorineural hearing loss.

OBJECTIVE: To observe and compare the efficacy of intratympanic application of dexamethasone (DXM) for the treatment of refractory sudden sensorineural hearing loss (SSNHL), the DXM was given in three different ways: by tympanic membrane injection, by drip through a ventilation tube, and by perfusion through a round window catheter. METHODS: We conducted a nonrandomized retrospective clinical trial involving 55 patients with refractory SSNHL. For 21 patients (the perfusion group), DXM (2.5 mg/0.5 ml) was perfused transtympanically through a round window catheter using an infusion pump for 1 h twice a day for 7 d giving a total amount of 35.0 mg. For 23 patients (the injection group), DXM (2.5 mg/time) was injected by tympanic membrane puncture at intervals of 2 d on a total of four occasions giving a total amount of 10.0 mg. For 11 patients (the drip group), DXM (2.5 mg/0.5 ml) was dripped via a ventilation tube placed by myringotomy, once on the first day and twice a day for the remaining 6 d giving a total amount of 32.5 mg. Thirty-two patients with refractory SSNHL who refused to undertake further treatments were defined as the control group. Hearing recovery and complications were compared among the groups. Hearing results were evaluated based on a four-frequency (0.5, 1.0, 2.0, 4.0 kHz) pure tone average (PTA). RESULTS: Post-treatment audiograms were obtained one month after treatments were completed. The improvements in average PTA for the perfusion, injection, and drip groups were 9.0, 8.6, and 1.7 dB, respectively. Hearing improvement was significantly greater in the perfusion and injection groups than in the control group (1.4 dB) (P<0.05). In the perfusion group, 8 out of 21 patients (38.1%) had a PTA improvement of 15‒56 dB (mean 29.8 dB); in the injection group, 8 out of 23 patients (34.8%) had a PTA improvement of 16‒54 dB (mean 24.9 dB); in the drip group, 1 of 11 patients (9.1%) had a PTA improvement of 26.0 dB; in the control group, 3 out of 32 patients (9.4%) had a PTA improvement of 15‒36 dB (mean 14.9 dB). CONCLUSIONS: Topical intratympanic application of DXM is a safe and effective method for the treatment of SSNHL cases that are refractory to conventional therapies.

Allelic imbalance and abnormal expression of FHIT in endemic nasopharyngeal carcinoma: association with clinicopathological features.

The FHIT gene is involved in the pathogenesis of many cancers. The aim of this study was to investigate allelic imbalance (AI) pattern at FHIT locus and alteration of FHIT gene in nasopharyngeal carcinoma (NPC) and analyzed potential correlation between AI, FHIT mRNA expression and clinicopathological factors. We examined AI, including loss of heterozygosity (LOH) and microsatellite instability (MSI), at FHIT locus in 41 cases of NPC by microsatellite analysis and FHIT gene status in 30 cases of NPC by nested reverse transcriptase-polymerase chain reaction and DNA sequencing. The frequencies of LOH and MSI at FHIT locus in NPC were 70.7% (29/41) and 36.6% (15/41), respectively. Thirteen of thirty (43.3%) NPCs exhibited aberrant FHIT transcripts. LOH and abnormal FHIT expression were correlated with advanced clinical stage and higher titers of immunoglobulin (Ig) A against Epstein-Barr virus capsid antigen (EBVCA-IgA) (p < 0.05). Abnormal FHIT expression was also correlated with tumor recurrence (p < 0.05). MSI was correlated with early clinical stage and higher titers of EBVCA-IgA (p < 0.05). AI at FHIT locus is a common event and contributes to genetic imbalance in NPC. The abnormalities of FHIT, presumably associated with genetic imbalance at FHIT locus, might be involved in the development and the tumor recurrence of NPC.

[Clinical observation of sensorineural hearing loss in patients suffering from nasopharyngeal carcinoma after radiotherapy].

OBJECTIVE: To study the extent and incidence of sensorineural hearing loss (SNHL) after radiotherapy (RT). METHODS: Twenty-eight patients with diagnosed nasopharyngeal carcinoma (NPC) were selected. The pure-tone audiography, auditory brain stem evoked response (ABR), impedance audiometry and evoked otoacoustic emissions (EOAE) recordings were performed before RT, 1 month, 1, 2 and 5 years after RT. RESULTS: At 1 month after RT, there were 7.1 and 25.7 dB increased mean bone conduction (BC) thresholds at speech (0.5 - 4.0 kHz) and at high frequency (8.0 kHz), and their BC thresholds were statistically significant increase than those before RT, respectively (P < 0.001). At 1 year after RT, there were 17.6 and 28.1 dB increased respectively, and their thresholds were statistically significant increase than those at pre-irradiation (P < 0.001). There were also significant increases in thresholds than those at 1 month of post-irradiation (P <0.001 or P < 0.05). At 2 years after RT, 21 and 27.4 dB were increased at respective those two frequencies, and there was a statistically difference only at speech frequencies when compared with those at 1 year after RT (P < 0.05). At 5 years after RT, 26.7 and 35.8 dB were increased at these two frequencies, and there were significant increases in threshold than those before, 1 month, 1 and 2 years after RT, respectively (P < 0.001). From 1 month to 5 years after RT, 37. 5% to 94. 7% of ears had a BC hearing threshold of at least 15 dB losses at speech frequency, whereas the percentage at high frequency was 85.4 to 97.4%. Up to 63.2% and 73.7% of ears had 30 dB SNHL at least at speech and high frequency, respectively. Furthermore, the degree of mean threshold loss was greater at high frequency than at speech frequency. The mean value of wave I, III and V latency, and I -V interpeak latency intervals of ABR had no significant difference between at 1 month after RT and before RT (P > 0.05). The wave I , III and V latency, and I - V interpeak latency intervals at 1 year and 2 years were significantly prolonged when compared with those before and 1 month after RT (P < 0.05), but there were no significant difference between 1 year and 2 years after RT (P > 0.05). The wave I, III and V latency, and I -V interpeak latency intervals at 5 years after RT were also significantly longer than those before RT (P < 0.001). There were significant difference in wave I , III and V latency (P < 0.05), and no significant difference in wave I - V interpeak latency intervals (P > 0. 05) between 5 years after RT and 1 year or 2 years after RT. Seven of 10 ears at 1 year after RT and 4 of 7 ears at 5 years after RT had normal EOAE, but they all had abnormal ABR response. CONCLUSIONS: SNHL in NPC patients start soon after completion of RT, especially more commonly in high frequency. The incidence and the extent of hearing loss are increased with time of follow-up. The hearing impairment could occur in the cochlea and/or the retrocochlear auditory pathway, which show that the sensitivity of radiation damage may be different in different patient and anatomic site of auditory system.

[Curative effect of transtympanic perfusion of gentamicin on unilateral Ménière's disease].

OBJECTIVE: To investigate the curative effect of transtympanic perfusion of gentamicin on unilateral Ménière's disease. METHODS: Twenty-three patients with unilateral Ménière's disease, 14 males and 9 females, aged 24 - 61, all with vertigo, tinnitus and ear fullness sensation to different degrees, were treated with transtympanic perfusion of gentamicin via the tympanostomy tube, 12 mg per 3 hours and 5 times a day. Pure tone audiometry and caloric test were performed every day before treatment. When destruction type of nystagmus was observed by Frenzel's glasses and the treated ear showed no response to caloric test, the treatment was ceased. After the treatment the patients were followed up for 9 - 11 years (10.2 years on average). RESULTS: The average amount of gentamicin used was 216 mg. The treatment lasted for 1.5 to 5 days (3.6 days on average). Vertigo disappeared in 21 patients (91%) and remained unchanged in 2. Hearing was improved or remained unchanged in 17 patients (73%) and became worse in 6. Tinnitus decreased or disappeared in 15 patients (66%), and increased in 2 patients. Ear fullness sensation decreased or disappeared in 21 patients (91%). and remained unchanged in 2. Twenty-one patients were completely recovered and returned to work (91%). CONCLUSION: Relieving intractable vertigo and preserving hearing, transtympanic perfusion of gentamicin is effective on unilateral Ménière's disease.