Objective: The purpose of this study is to retrospectively review the complications of patients who underwent cochlear implantation at 51 hospitals in mainland China over a decade. Methods: A retrospective analysis of 1,237 patients who underwent cochlear implantation from February 1998 to December 2008. The patients were reviewed for demographic information, type of hearing loss, abnormal findings on temporal CT scans, cochlear implant device, procedure time, and complications that included meningitis, hematoma (intracranial and extracranial), wound infection and implant extrusion, cerebrospinal fluid leak and facial palsy. Results: A total of 1,237 patient records were identified, and pertinent clinical information was reviewed. Of the patients, 59.6% were male, and 98.9% were prelingually deaf. The most common etiologies of hearing loss were: ototoxicity (28.1%), non-syndromic congenital hearing loss (14.8%), and inner ear malformation (18.5%). Inner ear malformations included: enlarged vestibular aqueduct (9.4%), Mondini defect (5.4%), common cavity (2.8%), cochlear ossification (3.9%), round window dysplasia (0.4%), and narrow internal auditory meatus (1.2%). The most common intraoperative complications were: gusher (5%) and electrode kinking (2.3%). The most common postoperative complications were hematoma (1.7%), wound infection and implant extrusion (0.5%), and device failure (0.9%). No CSF leakage or permanent facial palsy occurred. Conclusions: Cochlear implantation is a safe and reliable otosurgical procedure in China, and the rate of complications is similar to developed countries. Carefully preoperative preparation and standardization of the procedure are important for the development of cochlear implant programs in developing countries.

The trains of 200 ms biphasic square pulses with the width of 9 ms delivered at 50 Hz were found to be the most suitable and effective mean as stimulation in FES system of restoring the blink function in unilateral facial nerve paralysis rabbit model. FES system is a reliable tool for these patients. Facial paralysis affects thousands of people every year. Many will have long term facial difficulties and the loss of the ability to blink the eye, which can lead to potential loss of the eye. Although many treatments exist, no one approach corrects all the deficits associated with the loss of orbicularis oculi function. FES is a means of providing movement in paralysed muscles to assist with practical activities and one possible way of restoring blink and other functions in these patients. Although some previous researches had investigated the effect of simple FES system on restoration of paralyzed facial muscles, there is still controversy about the appropriate details of the most effective stimulating pulses, such as the frequency, wave pattern and pulse width. Our aim is to find out the parameters of the most appropriate and effective stimulatin verify it by a simple FES system. 24 healthy adult male New Zealand white rabbits were accepted the surgery of right side facial nerve main trunk transaction under general anesthesia as the unilateral facial nerve paralysis models. The platinum tungsten alloy electrodes were implanted in orbicularis oculi muscle. The parameters of stimulus pulses were set to a 200 ms biphasic pulse with different waveforms (square, sine and triangle), different frequencies (25, 50, 100 Hz) and different widths from 1 to 9 ms. Next, we set up a simple FES system to verify the previous results as the stimulus signal. We observed the movement of the both sides of eyelid when eye blink induced by different kinds of pulses. In all animals, the three kinds of waveforms pulse with frequency of 25 Hz could not evoke the smooth blink movement. But the pulses with frequency of 50 and 100 Hz can achieve this effect. The voltage threshold of the square pulse was lower than that of the sine pulse and triangle pulse. With the increase of pulse width from 1 to 9 ms, the voltage threshold decreased gradually. The voltage threshold of the pulse with frequency of 100 Hz was obviously lower than that of 50 Hz. But the amount of total charge of the stimulation pulse of 100 Hz was significantly more than that of 50 Hz. In addition, when the FES system was turned on, the eye blink on the affected side with the stimulation pulses that were set by the previous step results was successfully aroused by the blink movement as a trigger on the contralateral.

Immunoglobulin G4-related disease (IgG4-RD) is a chronic inflammatory disease involving multiple organs. Some studies have reported otological manifestations of IgG4-RD, although most studies describe involvement of the middle ear, and reports on inner ear manifestations are limited. Here, we describe a case of a 30-year-old man with IgG4-RD involving the inner ear. This case demonstrated that IgG4-RD affected the inner ear and caused cochlear ossification. Cochlear implants may be considered for milder cases, and hormone and immunosuppressive therapy may control disease progression.

It is still a difficult clinical issue to decide whether a patient is a suitable candidate for a cochlear implant and to plan postoperative rehabilitation, especially for some special cases, such as auditory neuropathy. A partial solution to these problems is to preoperatively evaluate the functional integrity of the auditory neural pathways. For evaluating the strength of phase-locking of auditory neurons, which was not reflected in previous methods using electrically evoked auditory brainstem response (EABR), a new method for recording phase-locking related auditory responses to electrical stimulation, called the electrically evoked frequency-following response (EFFR), was developed and evaluated using guinea pigs. The main objective was to assess feasibility of the method by testing whether the recorded signals reflected auditory neural responses or artifacts. The results showed the following: 1) the recorded signals were evoked by neuron responses rather than by artifact; 2) responses evoked by periodic signals were significantly higher than those evoked by the white noise; 3) the latency of the responses fell in the expected range; 4) the responses decreased significantly after death of the guinea pigs; and 5) the responses decreased significantly when the animal was replaced by an electrical resistance. All of these results suggest the method was valid. Recording obtained using complex tones with a missing fundamental component and using pure tones with various frequencies were consistent with those obtained using acoustic stimulation in previous studies.