Transtympanic injections of N-acetylcysteine for the prevention of cisplatin-induced ototoxicity: a feasible method with promising efficacy.

OBJECTIVES: Ototoxicity is a common and irreversible adverse effect of cisplatin treatment with great impact on the patients' quality of life. N-acetylcysteine is a low-molecular-weight agent which has shown substantial otoprotective activity. The role of transtympanic infusions of N-acetylcysteine was examined in a cohort of patients treated with cisplatin-based regimens. PATIENTS AND METHODS: Twenty cisplatin-treated patients were subjected, under local anesthesia, to transtympanic N-acetylcysteine (10%) infusions in 1 ear, during the hydration procedure preceding intravenous effusion of cisplatin. The contralateral ear was used as control. The number of transtympanic infusions was respective to the number of administered cycles. Hearing acuity was evaluated before each cycle with pure tone audiometry by an audiologist blinded to the treated ear. RESULTS: A total of 84 transtympanic infusions were performed. In treated ears, no significant changes in auditory thresholds were recorded. In the control ears cisplatin induced a significant decrease of auditory thresholds at the 8000 Hz frequency band (P=0.008). At the same frequency (8000 Hz), the changes in auditory thresholds were significantly larger for the control ears than the treated ones (P=0.005). An acute pain starting shortly after the injection and lasting for a few minutes seemed to be the only significant adverse effect. CONCLUSIONS: Transtympanic injections of N-acetylcysteine seem to be a feasible and effective otoprotective strategy for the prevention of cisplatin-induced ototoxicity. Additional studies are required to further clarify the efficiency of this treatment and determine the optimal dosage and protocol.

Treatment of the horizontal semicircular canal canalithiasis: pros and cons of the repositioning maneuvers in a clinical study and critical review of the literature.

OBJECTIVE: Several repositioning maneuvers have been proposed for the treatment of benign paroxysmal positional vertigo (BPPV) due to canalithiasis of the horizontal semicircular canal (HSC). However, comparisons between these canalith repositioning procedures as well as a generally accepted algorithm for the management of HSC canalithiasis are currently lacking. The aim of this study was to compare the efficacy of 3 different treatment proposals and review the relevant literature. STUDY DESIGN: Prospective clinical study. SETTING: Tertiary neurotology department. PATIENTS: Sixty patients diagnosed with HSC canalithiasis. INTERVENTIONS: A single application of Baloh's maneuver (n = 13), Vannucchi's forced prolonged position (n = 29), or Asprella-Gufoni maneuver (n = 18). MAIN OUTCOME MEASURES: Bilateral geotropic nystagmus. RESULTS: The first application of the Baloh's maneuver seemed to be significantly less effective than both Vannucchi's forced prolonged position (p = 0.035) and the Asprella-Gufoni maneuver (p = 0.006). No significant difference was detected in the efficiency of Vannucchi's forced prolonged position and the Asprella-Gufoni maneuver for this population (p = 0.4). CONCLUSION: The Asprella-Gufoni maneuver and Vannucchi's forced prolonged position both seem to be significantly more effective than the Baloh's maneuver in the treatment of HSC canalithiasis. The important pros of the Asprella-Gufoni maneuver versus Vannucchi's forced prolonged position are patient's convenience and maximal use of gravitational and angular acceleration forces. Controlled clinical studies are needed to conclude to an evidence-based proposal for the therapeutical steps that should be followed after the diagnosis of HSC canalithiasis.