Motor innervation of the human cricopharyngeus muscle

Innervation of the human cricopharyngeus muscle remains historically controversial and unclear, encouraging numerous treatments inconsistently designed to pharmacologically or mechanically alter the contractile state of this muscle. Neuroanatomic controversy results from and is perpetuated by 1) use of nonhuman models, 2) observational misinterpretation of small-diameter, overlapping nerve fibers, and, most importantly, 3) lack of real-time verification of neural projections. We sought to overcome these difficulties by performing microdissections in 27 patients undergoing laryngectomy and using real-time electromyographic verification. We demonstrated 1) dual ipsilateral innervation by the pharyngeal plexus and recurrent laryngeal nerve, 2) segmental projection of the recurrent laryngeal nerve to anterior motor units, 3) pharyngeal plexus projection to posterior motor units, 4) absence of a sympathetic or external superior laryngeal nerve contribution, and 5) absence of contralateral innervation. Such dual ipsilateral innervation, segmentally projected, has not been previously described in any other form of neuromuscular organization. Neuroanatomic accuracy should improve diagnostic and therapeutic strategies for future management of pharyngeal dysphagia.     

An electron microscopic study of the muscle spindle in the arytenoid muscle of the human larynx

Summary We used transmission electron microscopy to examine a muscle spindle found in serial sections of the arytenoid muscle of the human larynx. Eight intrafusal fibers were observed at the equatorial region and contained two types of muscle fibers, nuclear bag fibers and nuclear chain fibers. The sensory nerve endings found on the nuclear bag fibers were annular or varicose in shape and contained numerous mitochondria. Another small sensory ending was composed of many vesicles and some dense granules. The fusimotor nerve endings found on the nuclear chain fibers had three types of endings with different sizes and complexities.     

An electron microscopic study of the muscle spindle in the arytenoid muscle of the human larynx

We used transmission electron microscopy to examine a muscle spindle found in serial sections of the arytenoid muscle of the human larynx. Eight intrafusal fibers were observed at the equatorial region and contained two types of muscle fibers, nuclear bag fibers and nuclear chain fibers. The sensory nerve endings found on the nuclear bag fibers were annular or varicose in shape and contained numerous mitochondria. Another small sensory ending was composed of many vesicles and some dense granules. The fusimotor nerve endings found on the nuclear chain fibers had three types of endings with different sizes and complexities.     

杓状软骨复位术治疗环杓关节脱位的临床分析

摘要：目的探讨环杓关节脱位的临床特性以及杓状软骨复位的治疗技术。方法回顾性分析2014年7月~2017年4月收治的17例环杓关节脱位患者进行杓状软骨复位治疗的临床资料,分析其病因、治疗手法、诊治时机及疗效。结果17例患者中2例1次复位成功,3例2次复位成功,其余12例均行3~4次复位治疗,其中6例关节活动未能完全恢复正常,但所有患者发音质量GRBAS评分均有明显改善。结论杓状软骨复位是治疗环杓关节脱位的有效治疗方法,病程越短相对复位效果越满意,但较长病程患者进行复位治疗仍有助于嗓音改善。

     

Motor innervation of the eustachian tube muscles in the guinea pig

The brainstem location of motoneurons innervating eustachian tube-associated muscles in the adult guinea pig was determined using intramuscular injections of the neural tracer horseradish peroxidase (HRP). Following HRP injections into the tensor veli palatini and the eustachian tube belly of the medial pterygoid muscle, an ipsilateral column of HRP-labeled motoneurons was present medial to the dorsolateral division of the trigeminal motor nucleus. Following HRP injection into the levator veli palatini, labeled motoneurons were present in the ipsilateral dorsal division of nucleus ambiguus. The locations of the tensor veli palatini and levator veli palatini motoneurons are similar to those found in studies of other animals. A distinct eustachian tube belly of the medial pterygoid muscle was also identified. This sub-belly had a motoneuron pool distinct from the main medial pterygoid muscle group. The authors have provided the gross anatomical and neuroanatomical substrates upon which future studies of eustachian tube function in the guinea pig may be based.     

双蒂肌转入充填联合杓状软骨内移喉成形术治疗单侧声带麻痹

目的 探讨双蒂胸骨舌骨肌瓣转入声门旁联合杓状软骨内移治疗单侧声带麻痹的疗效.方法 不适合行喉返神经探查修复术的单侧声带麻痹19例.在甲状软骨板正中旁开0.5 cm裂开甲状软骨板,在杓状软骨内收固定的同时将带双蒂的胸骨舌骨肌瓣转入患侧声门旁内.治疗前后以电子喉镜、频闪喉镜、嗓音听评委主观评估、声学参数客观分析等评价治疗效果.结果 所有患侧声带膜部及声带突部术后即刻均明显内移,声带体积增大,发声时增大更为明显.术后2个月声门后裂隙消失6例,缩小13例;12个月后嗓音总嘶哑度评估:恢复正常6例,轻度声嘶12例,中度声嘶1例,较术前明显好转,采用等级资料数据秩和检验,差异具有统计学意义(z值为-4.062,P＜0.01).术后12个月的声门后裂隙、嗓音总嘶哑度与术后2个月比较无明显区别(P值均＞0.05).术后2个月及12个月声学客观指标的4个参数(基础频率、频率微扰、振幅微扰和谐噪比)平均值均明显小于术前,最长声时明显长于术前,差异均有统计学意义(P值均＜0.05).术后12个月与2个月比较上述参数差异均无统计学意义(P值均＞0.05).结论 双蒂胸骨舌骨肌充填联合杓状软骨内移喉成形术治疗不适合行喉返神经探查修复术的单侧声带麻痹患者的创伤小,无排异反应,远期效果较稳定.     

Involvement of carbon monoxide in the innervation of the canine cervical esophagus and trachea

We investigated the involvement of carbon monoxide (CO) in the innervation of the canine cervical esophagus and trachea by means of immunohistochemistry using an antiserum against heme oxygenase-2 (HO-2). We detected HO-2-immunoreactive nerve fibers around the blood vessels and submucosal glands of the esophagus and trachea. We found HO-2-immunoreactive neurons in ganglia in the trachea and in the myenteric plexus of the esophagus. These results suggest that CO is involved as a neurotransmitter in the innervation of the canine esophagus and trachea.     

Twitch response in the canine vocalis muscle

The twitch response of the canine vocalis muscle was investigated through a series of experiments conducted in vitro. Samples of vocalis muscle were dissected and prepared from canine larynges a few minutes before death and kept in Krebs solution at a temperature of 37 +/- 1 degrees C and pH of 7.4 +/- 0.05. Field stimulation with parallel-plate silver electrodes was applied to study the twitch response of muscle samples. The peak tension and time course of isometric contraction of isolated muscle samples were measured electronically with a Cambridge Technology Dual Servo System (ergometer). Contraction time and 50% relaxation time of this muscle were measured for seven samples at various levels of strain. It was found that contraction time ranged between 22 and 32 ms and 50% relaxation time ranged between 17 and 37 ms. Results indicate that the vocalis muscle is a fast muscle capable of performing rapid maneuvers in support of changes in fundamental frequency.     

Spontaneous dislocation of the arytenoid cartilage

Dislocation of the arytenoid cartilage occurs following medical instrumentation involving the laryngeal cavity or laryngeal injury from outside the larynx. We reported a case of spontaneously posterior dislocation of the arytenoid cartilage. A 53 year-old man suffering from suddenly recurring aphonia and its improvement many over 3 months without laryngeal injury or inducement eventually ceased to improve. Laryngoscopic findings showed that the left vocal fold was tensely prolonged and the vocal process of the arytenoid cartilage on the left side was dislocated posterolaterally. X-ray videofluorography of the larynx on repetitive phonation of /he/ showed abnormally high and diagonal displacement of the vocal fold and the upper structure of the arytenoid cartilage on the left side. Palpating the cricoarytenoid joint on the left side showed abnormal swelling with tenderness. Electomyography of the intrinsic laryngeal muscle on the left side showed normal action potential. From these findings, we diagnosed his voice disorder as spontaneously posterior dislocation of the arytenoid cartilage. We manually reduced it by pulling up a balloon inserted from the piriform sinus of the affected side to the esophagus.     

Pacing parameters of the canine posterior cricoarytenoid muscle

The electrical pacing of laryngeal tissue consists of many uncharted parameters. We carried out several acute experiments in the canine model to narrow parametric ranges to serve future research and development in this field. Our findings were as follows. Stimulation intensities greater than 6 V caused tissue damage. Optimum stimulation frequency ranged from 60 to 90 Hz. Optimum pulse duration was 2.0 milliseconds. Biphasic stimulation reduced accumulation of electrical charge at the electrodes.     

前庭器感觉上皮内神经分布的樱花联系

目的 了解前庭感觉上皮各神经成分间的横向联系,方法 对１０只（１６耳）健康豚鼠应用透射电观察其前庭感觉上皮区和上皮下区的神经分布。结果 发现Ⅰ、Ⅱ型感觉细胞间有十分密切的横向联系,传入、传出神经纤维及其末梢与神经纤维久干及其分支之间中联系。发生在前庭感觉上皮内的神经横向联系是非常复杂的,且是多层次,它们起源和终止于壶腹嵴或囊斑内。结论前庭感觉上皮内复杂的、以次的神经横向联系是前庭末梢器内部神经活动     

A new paramedian approach to arytenoid adduction and strap muscle transposition for vocal fold medialization

OBJECTIVE: To develop a prosthesis-free medialization laryngoplasty for the treatment of glottal incompetence. STUDY DESIGN: Twenty-two consecutive patients with glottal incompetence underwent vocal fold medialization using a new paramedian approach to arytenoid adduction and/or strap muscle transposition. METHODS: Under local anesthesia, the thyroid lamina on the involved side was parasagittally separated 5 mm off the midline. The inner perichondrium was carefully freed from the overlying thyroid cartilage. After dividing the thyrohyoid and cricothyroid membranes, the lamina was retracted laterally, the inner perichondrium was opened, and the lateral cricoarytenoid muscle identified. Tracing the muscle fibers posterosuperiorly, the muscular process of the arytenoid was identified. A 2-0 or 3-0 Prolene suture was placed through the muscular process and tied to the cricoid cartilage at the origin of the lateral cricoarytenoid muscle. A bipedicled strap muscle flap was then transposed into the space between the lamina and the inner perichondrium and the thyroid cartilages sutured back into place. Pre- and postoperative voice evaluations measured mean fundamental frequency, jitter, shimmer, noise-to-harmonic ratio, and maximal phonation time, as well as assessments of voice quality. RESULTS: Vocal improvement was obtained in 95% (21 of 22) of patients. There was a significant improvement (P <.05) in all parameters except shimmer. No major complications were noted in any patient, except for dyspnea in one patient resulting from arytenoid overrotation. CONCLUSION: The results suggest that a paramedian approach to arytenoid adduction combined with strap muscle transposition is a safe and effective method for treating glottal incompetence, particularly in patients with unilateral paralytic dysphonia.     

保留杓状软骨喉次全切除喉功能重建的体会

探讨应用保留杓状软骨的喉次全切除喉功能重建术治疗Ｔ３喉癌的拔管率和３、５年生存率。方法对２０例Ｔ３级喉癌,其中声门型３例,声门上型１７例,根据病变范围行保留单侧或双侧杓状软骨喉次全切除及功能重建术,并设计环咽吻合术式。