Pain assessment of the intratympanic injections: a prospective comparative study

The objective of the study is to compare the pain level of three methods of intratympanic (IT) injections using prospective, randomized clinical study in a tertiary care center. 39 patients with Ménière's disease and 30 patients with sudden sensorineural hearing loss are included. Excluded were patients treated for a chronic pain or those who took any pain killer for the last 24 h. Each patient received one IT injection a week, for three consecutive weeks. Three methods of IT injections were compared, with the application of EMLA cream on the tympanic membrane filling the external auditory canal 60 min before the procedure, with subcutaneous injection of lidocaine 1% with 1:100,000 epinephrine in the external auditory canal, and finally with an IT injection without any previous anesthesia. The pain intensity was immediately measured at 5 min, and then 45 min after the procedure, each time using four pain rating scales (visual analogue scale, numerical rating scale, verbal rating scale and categorical rating scale). No difference in pain intensity between the three methods of IT injections was detected by the visual analogue scale and numerical rating scale (p > 0.05). 45.8% of patients preferred the IT injection without previous anesthesia. However, methylprednisolone has been associated with pain intensity greater than that of gentamicin 45 min after the injection (p < 0.05). The IT injection performed without any previous anesthesia is an interesting option since it has not been shown to be more painful than the other methods of injections, and spares the patient from disadvantages associated with the anesthesia.