The Study on Effect and Neural Network Mechanism of Transcranial Direct Current Stimulation for Sudden Deafness With Tinnitus

This clinical study is prospective, single-center, randomized, controlled, double-blind clinical trail, which entitled transcranial electrical stimulation for the treatment of acute tinnitus approved by Sun Yat-sen University, and intends to recruit 86 patients with sudden deafness and tinnitus. For acute subjective tinnitus, a common otological disease, the study gave the experimental group patients received tDCS with electrodes positioned over the left temporal cortex for 5 days. To assess the efficacy of conventional medical therapy and tDCS by comparing changes in anterior and posterior tinnitus-related subjective scale scores, such as THI, VAS, BAI, BDI, PSQI, and hearing recovery, in patients who received tDCS, to determine whether tDCS is effective in improving acute tinnitus, and whether it is superior to conventional tinnitus treatment. In addition, the study will continue to follow patients for 1 month,3 months, and 6 months after the end of treatment to observe the long-term sustained efficacy of tDCS. This clinical trail will also evaluate tDCS from the perspective of compliance and safety, and explore the factors affecting the efficacy of this therapy.

Sample size estimation:

On-site recruitment will be conducted in the otolaryngology clinic for eligible patients with sudden deafness and tinnitus, with dedicated personnel to recruit subjects, with a total of at least 86 expected recruitment. In order to retain subjects, staff will tell them about the benefits of inclusion in clinical studies for sudden deafness with tinnitus, and actively add subjects' contact information to provide relevant consulting services for subjects during clinical studies. During follow-up, participants will be provided with a free tinnitus-related assessment test to motivate.

Plan for missing data： Screening failure, i.e. subjects did not meet the inclusion and exclusion criteria, or subjects withdrew informed consent, among other things for reasons why it was not included in this clinical study. Study subjects who failed to screen will be pressed according to their own condition Provide appropriate treatment according to clinical guidelines. This subset of subjects will not be included in clinical studies.

Statistical analysis plan:

When considering the influence of baseline, the continuous variables were analyzed by covariance analysis, and the qualitative indicators were tested by CMH test or logistic regression.

Primary analysis： Using covariance analysis to compare the different changes of THI scores between two groups after 5 days treatment, controlled for age and baseline THI.

Secondary analysis： Using covariance analysis to compare the different changes of VAS, BAI, BDI, PSQI scores between two groups after 5 days treatment, controlled for age and baseline values corresponding to each scale.

Using a repeated measure ANOVA to compare the different changes of THI, VAS, BAI, BDI, PSQI between two groups at 1, 3 and 6 follow-up visits.

Using Chi square test or Fisher exact test to compare the different efficient rate between two groups after 5 days treatment.

Exploratory analysis:

Using multiple linear regression analysis to explore the factors affecting the short-term and long -term efficacy of the two treatments, such as age, hearing loss threshold, tinnitus loudness, tinnitus frequency and so on.

Using Independent two sample t-test or nonparametric analysis to compare the differences in EEG- or fMRI-related indicators between two groups.

Safety analysis:

Using Pearson's chi-square test to compare the difference of adverse event incidence rate between two groups.

Eligibility Criteria:
Inclusion Criteria:

* Patients with tinnitus as the main complaint: patients subjectively feel sound in the ear or deep part of the head without internal or external sound stimulation, with or without hearing loss, and seek medical treatment
* Patients with sudden deafness with tinnitus whose course is less than 1 month and have not received any drug treatment
* Age 18-60 years
* Tinnitus frequency is 125-8000 Hz

Exclusion Criteria:

* Patients with conductive deafness, history of middle ear surgery, pulsatile tinnitus caused by vascular aberration and tinnitus cause by Meniere disease
* History of head trauma, central nervous system disease, mental disease, and drug abuse