Shicai Chen

Laryngeal reinnervation using ansa cervicalis for thyroid surgery-related unilateral vocal fold paralysis: a long-term outcome analysis of 237 cases.

Objective To evaluate the long-term efficacy of delayed laryngeal reinnervation using the main branch of the ansa cervicalis in treatment of unilateral vocal fold paralysis (UVFP) caused by thyroid surgery. Summary of Background Data UVFP remains a serious complication of thyroid surgery. Up to now, a completely satisfactory surgical treatment of UVFP has been elusive. Methods From Jan. 1996 to Jan. 2008, a total of 237 UVFP patients who underwent ansa cervicalis main branch-to-recurrent laryngeal nerve (RLN) anastomosis were enrolled as UVFP group; another 237 age- and gender-matched normal subjects served as control group. Videostroboscopy, vocal function assessment (acoustic analysis, perceptual evaluation and maximum phonation time), and electromyography were performed preoperatively and postoperatively. The mean follow-up period was 5.2±2.7 years, ranging from 2 to 12 years. Results Analysis of videostroboscopic findings indicated that the glottic closure, vocal fold edge, vocal fold position, phase symmetry and regularity were significantly improved in the UVFP group (P<0.001, postoperative vs. preoperative). The postoperative parameters of vocal function were also significantly improved in the UVFP group (P<0.001) and showed no statistical differences compared to the control group (P>0.05, respectively). Postoperative laryngeal electromyography confirmed successful reinnervation of laryngeal muscle. Conclusions Delayed laryngeal reinnervation with the main branch of ansa cervicalis is a feasible and effective approach for treatment of thyroid surgery-related UVFP; it can restore the physiological laryngeal phonatory function to the normal or a nearly normal voice quality.

Spontaneous regeneration of recurrent laryngeal nerve following long-term vocal fold paralysis in humans: histologic evidence.

To validate the occurrence of spontaneous regeneration of the recurrent laryngeal nerve (RLN) in patients with symptomatic vocal fold paralysis (VFP).

Effect of duration of denervation on outcomes of ansa-recurrent laryngeal nerve reinnervation

To investigate the efficacy of laryngeal reinnervation with ansa cervicalis among unilateral vocal fold paralysis (UVFP) patients with different denervation durations.

Reinnervation of Bilateral Posterior Cricoarytenoid Muscles Using the Left Phrenic Nerve in Patients with Bilateral Vocal Fold Paralysis

Objective To evaluate the feasibility, effectiveness, and safety of reinnervation of the bilateral posterior cricoarytenoid (PCA) muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis. Methods Forty-four patients with bilateral vocal fold paralysis who underwent reinnervation of the bilateral PCA muscles using the left phrenic nerve were enrolled in this study. Videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time, pulmonary function testing, and laryngeal electromyography were performed preoperatively and postoperatively. Patients were followed-up for at least 1 year after surgery. Results Videostroboscopy showed that within 1 year after reinnervation, abductive movement could be observed in the left vocal folds of 87% of patients and the right vocal folds of 72% of patients. Abductive excursion on the left side was significantly larger than that on the right side (P < 0.05); most of the vocal function parameters were improved postoperatively compared with the preoperative parameters, albeit without a significant difference (P > 0.05). No patients developed immediate dyspnea after surgery, and the pulmonary function parameters recovered to normal reference value levels within 1 year. Postoperative laryngeal electromyography confirmed successful reinnervation of the bilateral PCA muscles. Eighty-seven percent of patients in this series were decannulated and did not show obvious dyspnea after physical activity. Those who were decannulated after subsequent arytenoidectomy were not included in calculating the success rate of decannulation. Conclusions Reinnervation of the bilateral PCA muscles using the left phrenic nerve can restore inspiratory vocal fold abduction to a physiologically satisfactory extent while preserving phonatory function at the preoperative level without evident morbidity.

Contralateral ansa cervicalis-to-recurrent laryngeal nerve anastomosis for unilateral vocal fold paralysis: A long-term outcome analysis of 56 cases†‡

To evaluate the long‐term efficacy of contralateral ansa cervicalis‐to‐recurrent laryngeal nerve (RLN) anastomosis for unilateral vocal fold paralysis (UVFP), when the ansa cervicalis on the side of the paralyzed vocal fold was absent or there was any question about its viability.

Modulation of satellite cells in rat facial muscle following denervation and delayed reinnervation.

Abstract Conclusion: Long-term denervation-induced satellite cells (SCs) deficiency impairs facial muscle regenerative capacity. Delayed reinnervation can reactivate residual SCs to engage in muscle regeneration. However, the underlying mechanism remains to be elucidated. Objective: To evaluate the effects of denervation and delayed reinnervation on SCs in facial muscle. Methods: This was a prospective, randomized, controlled study in the rat facial nerve ligation and delayed decompression model. Animals were divided into denervation, 8-week-delay, and 16-week-delay reinnervation groups. Sham-operated animals served as a control group. Specific markers were used to investigate the differences in SC status, including quiescent (Pax7) and activated (myoD and myogenin) SCs and regenerative myofibers (embryonic myosin heavy chain, eMyHC). Quantitative assessment was performed by real-time PCR and Western blotting. Results: Activated SCs were detected 2–4 weeks after denervation and maintained for 4–8 weeks, accompanied by regenerating myofibers, whereas no SCs were detected beyond 20 weeks post-denervation. The myoD and myogenin up-regulation peaked 6–8 weeks after denervation and declined gradually to normal baseline 12 weeks after denervation. The 8-week-delay reinnervation group showed more activated SCs and regenerating myofibers than the 16-week-delay group, as well as greater up-regulation of myoD and myogenin (p < 0.05), suggesting reactivation of SCs for repair of adjacent fibers.

Changes in sleep characteristics and airway obstruction in OSAHS patients with multi-level obstruction following simple UPPP, UPPP-GA, or UPPP-TBA: a prospective, single-center, parallel group study.

Objective: To investigate changes in S3 sleep and the apnea hypopnea index (AHI), SpO2 desaturation and CT90, and to determine changes in the degree of airway collapse and in the cross-sectional area of the retropalatal and lingual region in obstructive sleep apnea hypopnea syndrome patients. Method: All subjects underwent overnight polysomnography and were evaluated using Müllers test and magnetic resonance imaging at baseline, 3, and 12 months following surgery. Result: The mean S3 scores in patients receiving uvulopalatopharyngoplasty combined with genioglossus advancement (UPPP-GA) or UPPP combined with tongue base advancement using the Repose™ system (UPPP-TBA) noticeably increased. Marked improvement was seen in the mean AHI, LSO2, and CT90 scores 3 and 12 months following surgery compared to baseline. Airway collapsed by 25-50% in the greatest proportion undergoing surgery at the tongue base. Conclusion: UPPP-GA and UPPP-TBA more effectively improve S3 sleep, and mean AHI, LSO2, and CT90 scores. In addition, they effectively alleviate airway obstruction by improving the cross-sectional area of these regions.

Bridging Gaps Between the Recurrent Laryngeal Nerve and Ansa Cervicalis Using Autologous Nerve Grafts

OBJECTIVES/HYPOTHESIS We investigated the clinical efficacy of free nerve grafts in bridging gaps between the recurrent laryngeal nerve (RLN) and ansa cervicalis in patients with unilateral RLN injury. STUDY DESIGN We retrospectively reviewed the charts of 14 patients who underwent relevant free nerve grafting and assessed the clinical outcomes of this procedure. METHODS Between January 2000 and January 2010, 14 patients with unilateral vocal fold paralysis were enrolled in this study. In all patients, the RLN was resected and free nerve grafts were applied to bridge the gap between the distal stump of the RLN and the anterior root of ansa cervicalis during surgery. Videostroboscopy, acoustic analysis, perceptual evaluation, maximum phonation time (MPT), and laryngeal electromyography (EMG) were performed both preoperatively and postoperatively to assess the clinical outcomes. RESULTS Videostroboscopic findings showed that glottic closure, vocal fold edge, vocal fold position, phase symmetry, and phase regularity were significantly improved postoperatively (P<0.05), and no paradoxical movements of vocal folds were observed. Perceptual evaluation showed that overall grade, roughness, breathiness, asthenia, and strain were also significantly decreased postoperatively (P<0.05). The acoustic parameters jitter (local) and shimmer (local) and the mean noise-to-harmonics ratio were significantly lower than the corresponding preoperative values (P<0.05). The postoperative MPT values were also significantly longer than the preoperative values. Laryngeal EMG revealed significant improvement in voluntary motor unit recruitment during phonation postoperatively (P<0.05). CONCLUSIONS Free nerve grafting is an effective procedure in bridging the gap between the RLN and ansa cervicalis in patients with unilateral RLN injury, as well as a safe procedure without obvious morbidity. A satisfactory vocal outcome can be obtained.

Expression of TGF-β1 and CTGF Is Associated with Fibrosis of Denervated Sternocleidomastoid Muscles in Mice

Injury to the recurrent laryngeal nerve often leads to permanent vocal cord paralysis, which has a significant negative impact on the quality of life. Long-term denervation can induce laryngeal muscle fibrosis, which obstructs the muscle recovery after laryngeal reinnervation. However, the mechanisms of fibrosis remain unclear. In this study, we aimed to analyze the changes in the expression of fibrosis-related factors, including transforming growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF), and α-smooth muscle actin (α-SMA) in denervated skeletal muscles using a mouse model of accessory nerve transection. Because of the small size, we used sternocleidomastoid muscles instead of laryngeal muscles for denervation experiments. Massons trichrome staining showed that the grade of atrophy and fibrosis of muscles became more severe with time, but showed a plateau at 4 weeks after denervation, followed by a slow decrease. Quantitative assessment and immunohistochemistry showed that TGF-β1 expression peaked at 1 week after denervation (p < 0.05) and was maintained at its high level until 4 weeks. CTGF- and α-SMA-positive muscle cells were detected at 1 week after denervation, peaked at 2 weeks (p < 0.05), and remained at high levels with a subsequent slight decrease for 3-4 weeks. These results suggest that TGF-β1 and CTGF may be involved in the process of denervated skeletal muscle fibrosis. They may induce the differentiation of myoblasts into myofibroblasts, as characterized by the activation of α-SMA. These findings may provide insights on key pathological processes in denervated skeletal muscle fibrosis and develop novel therapeutic strategies.

Free flap combined with pectoralis major flap for reconstruction after total laryngopharyngectomy in patients with advanced hypopharyngeal carcinoma

Abstract Conclusion: The findings suggest that a pectoralis major flap combined with a free flap is a safe and reliable method of reconstruction after total pharyngolaryngectomy; with this technique, one can help these patients remain disease free, with normal swallowing function, for a relatively acceptable survival duration. Objectives: To determine the functional and oncological outcomes of a combined flap for the extensive defects after total pharyngolaryngectomy in patients with advanced squamous cell carcinoma of the hypopharynx (SCCHP). Method: This study determined the perioperative morbidity and functional and oncologic outcomes of 21 patients with advanced SCCHP who underwent total laryngopharyngectomy and reconstruction using a combination of a pectoralis major flap and a free flap. Results: The free flap and pectoralis major flap were used to reconstruct the defects for all 21 patients. Fourteen patients were reconstructed with jejunal free flaps and pectoralis major flaps; in the remaining seven patients, anterolateral thigh flaps and pectoralis major flaps were used. All the combined flaps worked well, and patients recovered normal swallowing function a mean 19.4 days after surgery. After an overall mean follow-up time of 31.3 months, 30% of patients were still alive at the time of this analysis, with no evidence of disease.