Application of lipid and polymeric-based nanoparticles for treatment of inner ear infections via XGBoost.

Taking hearing loss as a prevalent sensory disorder, the restricted permeability of blood flow and the blood-labyrinth barrier in the inner ear pose significant challenges to transporting drugs to the inner ear tissues. The current options for hear loss consist of cochlear surgery, medication, and hearing devices. There are some restrictions to the conventional drug delivery methods to treat inner ear illnesses, however, different smart nanoparticles, including inorganic-based nanoparticles, have been presented to regulate drug administration, enhance the targeting of particular cells, and decrease systemic adverse effects. Zinc oxide nanoparticles possess distinct characteristics that facilitate accurate drug delivery, improved targeting of specific cells, and minimized systemic adverse effects. Zinc oxide nanoparticles was studied for targeted delivery and controlled release of therapeutic drugs within specific cells. XGBoost model is used on the Wideband Absorbance Immittance (WAI) measuring test after cochlear surgery. There were 90 middle ear effusion samples (ages = 1-10 years, mean = 34.9 months) had chronic middle ear effusion for four months and verified effusion for seven weeks. In this research, 400 sets underwent wideband absorbance imaging (WAI) to assess inner ear performance after surgery. Among them, 60 patients had effusion Otitis Media with Effusion (OME), while 30 ones had normal ears (control). OME ears showed significantly lower absorbance at 250, 500, and 1000 Hz than controls (p < 0.001). Absorbance thresholds >0.252 (1000 Hz) and >0.330 (2000 Hz) predicted a favorable prognosis (p < 0.05, odds ratio: 6). It means that cochlear surgery and WAI showed high function in diagnosis and treatment of inner ear infections. Regarding the R2 0.899 and RMSE 1.223, XGBoost shows excellent specificity and sensitivity for categorizing ears as having effusions absent or present or partial or complete flows present, with areas under the curve (1-0.944).

Refining feasibility assessment of endoscopic ear surgery: a radiomics model utilizing machine learning on external auditory canal CT scans.

BACKGROUND: Feasibility assessment of endoscopic ear surgery (EES) relies solely on subjective evaluation by surgeons. OBJECTIVE: Extracting radiomic features from preoperative CT images of the external auditory canal, we aim to classify EES patients into easy and difficult groups and improve accuracy in determining surgery feasibility. METHODS: 85 patients' external auditory canal CT scans were collected and 139 radiomic features were extracted using PyRadiomics. The most relevant features were selected and three machine learning algorithms (logistic regression, support vector machine, and random forest) were compared using K-fold cross-validation (k = 5) to predict surgical feasibility. RESULTS: The best-performing machine learning model, the support vector machine (SVM), was selected to predict the difficulty of EES. The proposed model achieved a high accuracy of 86.5%, and F1 score of 84.6%. The area under the ROC curve was 0.93, indicating good discriminatory power. CONCLUSIONS AND SIGNIFICANCE: The proposed machine learning model provides a reliable and accurate method for classifying patients undergoing otologic surgery based on preoperative imaging data. The model can help clinicians to better prepare for challenging surgical cases and optimize treatment plans for individual patients.

Transcanal endoscopic management of isolated congenital middle ear malformations.

BACKGROUND: A few studies have reported transcanal endoscopic management of isolated congenital middle ear malformations (CMEMs). OBJECTIVE: The purpose of this study is to describe our surgical experience in endoscopic ear surgery for isolated CMEMs and evaluate the surgical effect of hearing reconstruction. METHODS: From January 2017 to January 2022, a retrospective study was performed on 36 patients (37 ears) with isolated CMEMs who all underwent endoscopic surgery. Demographic data, high-resolution computed tomography (HRCT) findings, intraoperative findings, surgical management and audiometric data were recorded. RESULTS: Anomalies were categorized according to the Teunissen and Cremers classification system: 8 ears were categorized as class I, 8 ears as class II, 19 ears as class III and 2 ears as class IV. The air conduction pure tone average (AC-PTA) of 37 cases was 61.5 ± 8.6 dB preoperatively and 29.6 ± 6.9 dB postoperatively (p < 0.001). The mean preoperative air-bone gap (ABG) significantly decreased from 43.1 ± 8.7 dB to 12.8 ± 5.5 dB postoperatively. 36 of 37 cases (97%) met the criteria for successful operation. CONCLUSION: Isolated CMEMs are mainly manifested as aplasia of the stapes' superstructure and dysplasia of the long process of the incus. Transcanal endoscopic surgery seems a safe technique for the management of isolated CMEMs.

Endoscopic type 1 tympanoplasty: comparison of the effects of three different thicknesses grafts.

BACKGROUND: The effects of graft thickness on tympanoplasty is uncertain. OBJECTIVE: To compare the results of endoscopic tympanoplasty using different thicknesses of autologous tissues. METHODS: This retrospective analysis included 186 patients who received type I tympanoplasty, divided into three main groups based of grafting material: perichondrium (A), cartilage-perichondrium (B), or cartilage-perichondrium plus additional perichondrium (C). Group A was subdivided based on whether the placement was inside (A1) or outside (A2) of the malleus. The hearing improvement, graft success rate, and surgery duration were analysed. RESULTS: Statistical analysis showed significant hearing improvement in the three main groups (p < .001); recovery in group A occurred the earliest. Six months postoperatively, group A1 showed significantly greater hearing recovery compared with groups B and C (p < .05). There were no statistical differences the other groups (p > .05) or in the graft success rate among the three main groups (p = .235). The surgery duration of group A was significantly longer than that of groups B and C (p < .001). CONCLUSION AND SIGNIFICANCE: Our results suggest that graft thickness affects hearing recovery; however, graft thickness does not affect the rate of grafting success. Endoscopic transplantation of the perichondrium is more difficult and requires more time.

Low expression of CIP4 in predicting worse overall survival: A potential biomarker for laryngeal cancer.

Previous reports indicate that Cdc42-interacting protein-4 (CIP4) has previously been reported to plays an important role in the progression of various cancers. However, its correlation with laryngeal cancer (LC) remains unreported. Data from TCGA and GEO databases were used to evaluate the role of CIP4 in LC. Based on GEO and TCGA datasets, we analyzed the differences in CIP4 expression between normal and tumor samples. The Wilcoxon signed-rank test was used to analyze the relationship between clinical features and CIP4. Cox regression and the Kaplan-Meier analyses were used to identify the clinical characteristics associated with the overall survival. Also, the GEPIA database was used to confirm the relationship between CIP4 and overall survival. Lastly, Gene Set Enrichment Analysis (GSEA) was performed based on the TCGA dataset. CIP4 expression in LC was significantly associated with gender and tumor stage (p-values<0.05). Similar to GEPIA validation, Kaplan-Meier survival analysis demonstrated that LC with CIP4-low exhibited a worse prognosis than that with CIP4-high. Univariate analysis revealed that CIP4-high significantly correlated with better overall survival (HR: 0.522, 95% CI: 0.293-0.830, P = 0.026). Besides, multivariate analysis revealed that CIP4 remained independently associated with the overall survival (HR: 0.61, 95% CI: 0.326-0.912, P = 0.012). GSEA showed that the p53, WNT signaling, TGF-ß signaling pathways, etc. were enriched in a phenotype high CIP4 expression. In summary, the CIP4 gene is a potential prognostic molecular marker for patients diagnosed with laryngeal cancer. Moreover, the p53, WNT signaling, and TGF-ß signaling pathways are potentially associated with CIP4 in LC.

Hair Cell Protection from Ototoxic Drugs.

Hearing loss is often caused by death of sensory hair cells (HCs) in the inner ear. HCs are vulnerable to some ototoxic drugs, such as aminoglycosides(AGs) and the cisplatin.The most predominant form of drug-induced cell death is apoptosis. Many efforts have been made to protect HCs from cell death after ototoxic drug exposure. These mechanisms and potential targets of HCs protection will be discussed in this review.And we also propose further investigation in the field of HCs necrosis and regeneration, as well as future clinical utilization.

Comparison of Tympanic Membrane Perforation With and Without Calcification of Anterior Mallear Ligament Under Transcanal Endoscopic Type I Tympanoplasty.

OBJECTIVES: Chronic suppurative otitis media (CSOM) induced tympanic membrane perforation (TMP) can be accompanied by anterior mallear ligament (AML) calcification. So far, comparative evaluations of TMP with and without AML calcification have rarely been reported. The aim of the current study is to compare the hearing outcomes of TMP with and without calcification of AML under transcanal endoscopic type I tympanoplasty. METHODS: Records of 67 patients diagnosed with CSOM and receiving transcanal endoscopic type I tympanoplasty were divided into the AML calcification group (Cal group, n = 31) and the non-AML calcification group (non-Cal group, n = 36). The 31 patients in the Cal group were divided into subgroup A and B according to the severity of calcification. The operation time, closure rate, and pre- and postoperative audiometric results were retrospectively collected and analyzed. RESULTS: Preoperatively, the Cal group had higher mean air-bone gap (ABG; P = .022), and ABGs at 250 Hz (P = .017) and 500 Hz (P = .008) compared with the non-Cal groups. The Cal group showed higher improvements of ABGs at 250 Hz (P = .039) and 500 Hz (P = .021) compared with the non-Cal groups postoperatively. CONCLUSIONS: The TMP with AML calcification leads to higher ABGs at low frequencies. The hearing outcomes are similar for TMP both with and without AML calcification after surgery. Our results suggest that transcanal endoscopic type I tympanoplasty is an appropriate surgical method for TMP with AML calcification, if the lesion can be detected and completely eliminated.

Comparison of endoscopic type I tympanoplasty with and without assistance of customized 3D-printed guiding template for tympanic membrane.

PURPOSE: To compare the anatomical and audiological outcomes of endoscopic type I tympanoplasty using cartilage-perichondrium, with or without a customized 3D-printed guiding template. MATERIALS AND METHODS: A total of 60 patients with tympanic membrane perforation receiving endoscopic type I tympanoplasty were divided into the non-template group (group 1, n = 30) and template group (group 2, n = 30). Closure rate, hearing outcomes and operating time were compared between the two groups. RESULTS: Group1 had a significant higher operation time compared with group2 (77.73 ± 10.63 min vs. 66.23 ± 14.92 min, p = 0.001). The overall closure rate of group1 was lower than that of group2 (83.33% vs. 100%, p = 0.052). The postoperative air-bone gaps (ABGs) were significantly lower than preoperative ones in each group (p < 0.001, respectively). CONCLUSIONS: Improvements in hearing outcomes were comparable for the two groups. The applying of customized 3D-printed guiding template resulted in a higher closure rate and a shorter operation time. Our results suggest that the customized 3D-printed guiding template can be recommended as a useful aid for endoscopic type I tympanoplasty.

Survival benefit of induction chemotherapy in treatment for stage III or IV locally advanced nasopharyngeal carcinoma - An updated meta-analysis and systematic review.

PURPOSE: The purpose of this study was to investigate whether combined Induction chemotherapy (IC) with concurrent chemoradiotherapy (CCRT) for stage III or IV locally advanced nasopharyngeal carcinoma (LA-NPC) could achieve better survival benefits than CCRT alone. MATERIALS AND METHODS: Only randomized controlled trials were included in this study. There were two treatment regiments (IC + CCRT and CCRT alone) recruited for analysis. The end points of this meta-analysis were overall survival (OS), locoregional recurrence-free survival (LRFS), and distant metastases-free survival (DMFS). Then we performed a traditional meta-analysis. RESULTS: Seven studies were included, including 2628 patients. Compared with using CCRT alone, IC + CCRT has better effects on overall survival (OS) [HR = 0.75, 95% CI = 0.63-0.89], locoregional recurrence-free survival (LRFS) [HR = 0.70, 95% CI = 0.56-0.86] and distant metastasis-free survival (DMFS) [HR = 0.65, 95% CI = 0.54-0.78]. Of note, the addition of IC also increases the incidence of toxic reactions and patient discomfort. CONCLUSION: IC + CCRT provided better survival benefits than CCRT alone. However, patients also had a higher incidence of toxic reactions with combination therapy.

Would endoscopic surgery be the gold standard for stapes surgery in the future? A systematic review and meta-analysis.

OBJECTIVE: This meta-analysis is aimed to review and analyze all available data of intraoperative and postoperative results of endoscopic and microscopic stapes surgery. METHODS: According to the PRISMA statements checklist, this systematic review and meta-analysis were designed. Data were extracted from public databases, such as PubMed, Cochrane, Web of Science, and more. The quality of studies was evaluated using the MINORS scale. Odds ratios (ORs) and 95% CIs were estimated for binary outcome data, while the mean differences and 95% CIs were estimated for continuous data. I2 and χ2 tests were used to quantify statistical heterogeneity. If more than ten studies were included in each analysis, funnel plot would be performed to analysis publication bias. RESULTS: Twelve studies with 620 patients were included in this meta-analysis. Primary outcomes collected in this meta-analysis included average postoperative auditory gain (APAG), postoperative air-bone gap (ABG), the rate of chorda tympani handling and bone curettage, which all showed a statistically significant difference in favor of endoscopy. While only secondary outcomes about postoperative pain and dysgeusia demonstrated a significantly reduced incidence. Furthermore, there was not any statistically significant difference on postoperative dizziness and average operative time between endoscopy and microscopy. CONCLUSION: Although there is a need for high-quality pooled data in the future, a consistently superior effect of the endoscopic group was still shown in terms of total effectiveness, when compared to the microscopic group. We have reasons to support the application of endoscopy in stapes surgery. The future of ESS, we believe, is blazing bright.

Auricular suppurative perichondritis secondary to exclusive endoscopic ear surgery for tympanoplasty: A case report and literature review.

Endoscope is an innovative method for otologists in middle ear surgery. Many previous studies have confirmed the safety and efficiency of the endoscopic technique, as a reliable therapeutic option with very low complication rates, clearly supporting the use of endoscopy in ear surgery. Auricular suppurative perichondritis secondary to exclusive endoscopic ear surgery for tympanoplasty is an extremely rare type of those without any previously reported cases. In this report, we describe the course of auricular suppurative perichondritis of a 55-year-old woman. The patient was ultimately healed through surgical debridement and postoperative dressing with no evidence of recurrence at two months follow-up. There were no auricle deformity or external auditory canal stenosis with six months following-up.

Effects of bleomycin A5 on caspase-3, P53, bcl-2 expression and telomerase activity in vascular endothelial cells.

OBJECTIVE: The aim of this study was to investigate the molecular mechanism of bleomycin A5 in inducing the apoptosis of human umbilical vein endothelial cells (ECV304). MATERIALS AND METHODS: ECV304 cells were cultured and passaged, and then were divided into control group and three treatment groups. The later three groups were treated with 15, 75, and 150 µg/ml bleomycin A5 for 24 hours, respectively. The expressions of caspase-3, p53, and bcl-2 in ECV304 cells were detected by flow cytometry, and the activity of telomerase was determined using telomere repeat amplification protocol (TRAP)-silver staining method. RESULTS: After treatment with different concentrations of bleomycin A5, the expression of caspase-3 in ECV304 cells was increased. It was significantly decreased with the increase of bleomycin A5 concentration, but the difference between 75 µg/ml and 150 µg/ml groups was not significant. Bleomycin A5 could significantly increase the expression of p53, with concentration dependence. It had no obvious effect on bcl-2 expression. There was high expression of telomerase in control group. After treatment with different concentration of bleomycin A5, the telomerase activity was significantly decreased. CONCLUSION: Bleomycin A5 can increase caspase-3 and p53 levels and inhibit telomerase activity to induce ECV304 apoptosis.

Proapoptotic effect and the mechanism of action of pingyangmycin on cavernous hemangiomas.

This study aimed to investigate the proapoptotic effects and the mechanism of action of pingyangmycin (PY) on cavernous hemangioma. The rat spleen was used as a model of cavernous hemangioma. PY was injected into the spleen and the pathological changes were observed at different time-points. Apoptosis was detected using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and transmission electron microscopy (TEM). The expression levels of the apoptosis-related protein, caspase-3, were determined using immunohistochemistry and image analysis. Rats injected with normal saline were the control group. Injection of normal saline did not damage rat spleens. On days 2 and 5 following PY injection, the spleens exhibited slight swelling. On days 8 and 14, atrophic changes were observed and the splenic sinus endothelial cells were damaged. At various time-points following PY injection, the apoptotic cells were observed by TEM. The TUNEL assay showed that apoptosis occurred widely among the splenic sinus endothelial cells and other splenic cells. The apoptotic rate and caspase-3 expression levels increased with prolonged PY exposure. PY induced apoptosis of splenic sinus endothelial cells through the caspase-3 activation pathway, and resulted in endothelial cell necrosis and fibroblast hyperplasia.

[Effects of two surgical techniques for vocal cord cyst].

OBJECTIVE: To compare the effectiveness of vocal cord cyst excision with electronic laryngoscope (EL) and self-retaining laryngoscope (SRM). METHOD: Nightly-two patients, diagnosed as vocal cord cyst with strobolaryngoscope or electronic laryngoscope, were randomly divided into two groups. One group was 48 cases treated with electronic laryngoscope and another group was 44 cases treated with self-retaining laryngoscope. Electronic laryngoscopy examination and voice function assessments were performed to all patients, preoperatively and postoperatively at one week, three months and six months. RESULT: One failed cases under SRM, difficult exposure of glottic portion, were treated under EL. The recurrence rate of the two groups was of no statistical significance in three months after operation. Voice function assessment of the two groups was of no statistical significance at one week, three months and six months after operation. CONCLUSION: The operation under electronic laryngoscope is a minimal invasive procedure to the laryngeal mucosa. Electronic laryngoscope had advantages such as clear view, accurate operation. Furthermore, it can be used for those that could not be treated under self-retaining laryngoscope.

[The recovery study of excising the different range of dog's anterior commissure by semiconductor laser].

OBJECTIVE: To explore the effective method to treat the glottic carcinoma invading the anterior commissure, we observed the difference of three kinds of operation to the anterior commissure of dogs by semiconductor laser. METHOD: Twelve dogs were divided into 3 groups at random, A: to cauterize to the thyroid cartilage's inner membrane of the anterior commissure, the right ventricular bands and vocal cord, the anterior and 1/3 of the left vocal cord; B: to cauterize part of the thyroid cartilage of the anterior commissure besides A; C: to open a window about 5 mm x 5 mm on the thyroid cartilage of the anterior commissure besides B. To take photos to observe the dogs' laryngeal wound with digital camera or electrolaryngoscope immediately, 1 week and 4 weeks, then to record the hoarseness, body weight and complications etc. RESULT: All the dogs' laser surgery were completed successfully. To observe the gross specimen, it was identical between the extent of excising and the design preoperation. One week later, the neonatal membrane covered the wound incomplete. Edematization, inflammatory reaction, pseudomembrane and the hoarseness were not heavy too. No obvious complication in group A. The neonatal membrane covered the wound incomplete. Edema, inflammatory reaction, pseudomembrane and granulation can be seen in group B. Exudation was heavy in local, erosion and infected, the hoarseness was severe. No other obvious complications in C. Different extent of adhesion could be seen at the anterior commissure in group A, B and C after 4 weeks, the laryngeal web formed, and the length of vocal cord was shorter than before. The color and luster of anterior commissure membrane was normal basically, the inflammatory reaction was not heavy in A and B groups. The anterior commissural membrane appeared the dark red chronic inflammatory reaction; the window was closed by neonatal membrane completely and had no infection in group C. To observe the gross specimen: the wound of anterior commissure was covered by prosthetic epithelia completely in three groups. The window was closed by complete membrane at the anterior commissure. The No. 1- 3 dog's conditions of hoarseness in three groups after 4 weeks: slight in A group, little severe in B and C group. The change of weight was not obvious at the pre or postoperative in group A and B. No obvious complication happened in each group postoperation. CONCLUSION: The three operative methods have satisfied effects,the recovery of wound can cure well finally and no severe complications happened. It is valuable in clinic.

[Glottic measurement and vocal evaluation after three surgical techniques in the treatment of bilateral vocal cord paralysis].

OBJECTIVE: To evaluate postoperative glottic area and vocal quality of three various surgical techniques for treating bilateral vocal cord paralysis, including laser arytenoidectomy (Group A, 24 cases), reinnervation of the posterior cricoarytenoid muscle by phrenic nerve (Group B, 9 cases) and arytenoidectomy accompanying lateral cordopexy by extralaryngeal approach (Woodman's procedure, Group C, 13 cases). METHODS: 46 cases suffered from bilateral recurrent laryngeal nerve injury were included in our study. The pre-postoperative glottic measurement and vocal acoustic parameters were analyzed. RESULTS: The decannulated cases in group A and group B and group C were 22, 8, 13 respectively. The post-operative mean maximal glottic area was (47.2 +/- 7.4) mm2, (78.3 +/- 16.0) mm2, (48.1 +/- 6.5) mm2 respectively. Group B cases glottic area was larger than that of group A and group C (t value were 4.46 and 3.85, P value were 0.000 and 0.001). No significant difference was found between group A and group C (t = 1.68, P = 0.101). After surgery, in group A, 17 cases voice quality was the same compared with that of before surgery, and 7 cases voice quality had become worse; In group B, the voice quality had become better in 5 cases, completely recovered in 1 case, and had not change in 3 cases; In group C, the voice quality had become deteriorated in 10 cases and no change in 3 cases. And in group B, ipsilateral diaphragm paralysis in 9 cases after surgery, whose vital capacity and forced vital capacity had decreased to 72%-84%, 76%-84% of that before the surgery respectively; and the diaphragm mobility had recovered by 35%-76% respectively, while vital capacity and forced vital capacity had become 93%-97%, 91%-98% of that before the surgery. In Group B, all cases' pulmonary function was normal half a year postoperatively. CONCLUSIONS: Reinnervation of the posterior cricoarytenoid muscle by phrenic nerve seems to be best procedure with better post-operative voice and larger glottic area. Although the sufficient airway for decannulation can be acquired in Group A and Group C, but most of patients in Group A had pre-operative vocal level and badly abnormal in Group C.

[Intratumor bleomycin-A5 injection under electrolaryngoscope for treatment of large laryngopharyngeal and laryngeal hemangioma].

OBJECTIVE: To study the therapeutic effect of bleomycin-A5 injection under eletrolaryngoscope for treatment of large laryngopharyngeal and laryngeal hemangioma. METHODS: Intratumor bleomycin-A5 injection under eletrolaryngoscope was performed in 18 cases of large laryngopharyngeal and laryngeal hemangioma with surface anaesthesia, for totally 7 to 14 (mean 10.2) injections in each case. RESULTS: Twelve patients were cured and 6 showed obvious improvement. Follow-up of the patients for over one year found no recurrence of the hemangioma. CONCLUSION: Bleomycin-A5 injection is a minimal invasive procedure for treatment of large laryngopharyngeal and laryngeal hemangioma, causing less pain and better preserving the laryngeal function without the necessity of tracheotomy.

[Glottic measurement and vocal evaluation before and after adult arytenoidectomy].

OBJECTIVE: To study minimal glottic area which can acquire sufficient airway for decannulation and maximal glottic area which can maintain preoperative vocal function on adult bilateral vocal cord paralysis with unilateral arytenoidectomy. METHODS: Sixteen adult received microscopic right arytenoidectomy with Diomed-25 laser under general anaesthesia and sustained laryngoscope from September 1998 to February 2003. The pre-postoperative glottic measurement and vocal acoustic parameters were analyzed. RESULTS: The postoperative maximal glottic area, maximal posterior glottic width and maximal opening angle between bilateral vocal cords of the 15 decannulated cases were (45.93 +/- 6.56) mm2, (4.97 +/- 0.73) mm and (24.34 +/- 4.74) degrees respectively. Compared with preoperative period, there were significant difference. Pre-postoperative acoustic parameters (Jitter, Shimmer, harmonics-noise ratio) were analyzed and no significant difference were found (P > 0.05, but there are significant difference in NNE (normalized noise energy) and MPT (maximum phonation time) (P < 0.05). Except for three cases whose postoperative glottic area were more than 50. 1 mm2, there were no significant difference in pre and postoperative NNE (P > 0.05). The minimal glottic area decannulated was 38.0 mm2. The more opening maximal glottic area, the greater of NNE because of bigger closing gap. Noticeable increase of NNE was observed when maximal opening glottic area was up to 50.1 mm2. CONCLUSIONS: The minimal glottic area for decannulation should be 38.0 mm2, and the maximal glottic area for maintaining preoperation vocal function should be 50.1 mm2 on adult bilateral voca cord paralysis with laser aryntenoidectomy.

[Nerve exploration and decompression for traumatic recurrent laryngeal nerve injuries induced by thyroid gland surgery].

OBJECTIVE: To show the findings of recurrent laryngeal nerve injury exploration and find out therapeutic effects, indications and timing of nerve decompression for traumatic recurrent laryngeal nerve injury induced by thyroid gland surgery. METHODS: In this study there were 87 patients with recurrent laryngeal nerve injury, including 65 for nerve exploration and 22 for nonsurgical treatment. During nerve exploration, the types, severity of laryngeal nerve injuries and laryngeal muscular mass were studied. Nerve decompression was performed in these 14 patients whose compressing sutures or compression due to cicatricial hypertrophy were received nerve decompression. RESULTS: Injuries caused by thyroid gland operations mostly are of suture ligation (43%) and nerve severance (48%); simple scar compression was found only in 6 cases (9%). Atrophy of the laryngeal muscles was not very serious in patients with a course less than 6 months. In 10 patients with a course less than three months, nerve decompression restored normal functional abductor and abductor motion of the vocal cord in 9 patients and had no effects in one. Although functional motion of vocal cord was not seen in one case with a course less than 3 months and 4 cases between 3 and 5 months, the mass and tension of the reinnervated vocal cord became much the same as the contralateral normal vocal cord, thus resuming symmetric vibration of the vocal cords and physiological phonation. Although nonsurgical treatment improved severe hoarseness, it didn't restore normal functional motion of the vocal cord and normal voice. CONCLUSIONS: Nerve exploration showed a primary rule for recurrent laryngeal nerve injury induced by thyroid gland surgery. Early and mid-stage recurrent laryngeal nerve exploration and decompression may restore normal motion of the glottis, and it suggested laryngeal delayed reinnervation may help patients with a course more than 6 months.