Gender dysphoria and the larynx
Declan Costello, Guri Sandhu in Practical Laryngology, 2015
An appreciation of the function of two intrinsic laryngeal muscles allows for a better understanding of how surgery for elevating vocal pitch has evolved: The cricothyroid muscle takes its origin from the anterior surface of the arch of the cricoid and inserts into the antero-lateral surface of the thyroid cartilage. Its action is to lengthen and exert tension on the vocal cord. By elevating the arch of the cricoid the distance between the angle of the thyroid cartilage and the vocal process of the arytenoids is increased (Figure 19.1).The thyroarytenoid muscle passes from the base and anterior surface of the arytenoid cartilage to the inner surface of the thyroid cartilage in the midline. The thyroarytenoid muscle shortens the vocal fold and adjusts the tension within it during phonation.
Anatomy overview
Stephanie Martin in Working with Voice Disorders, 2020
As the thyroarytenoid muscle comprises the bulk of the vocal folds it is important to look at the structure and histology of the vocal folds in more detail. The vocal folds consist of five different layers as follows: The outer layer or integument, which maintains the shape of the vocal fold, consists mainly of columnar epithelium apart from the medial edge and is subject to the greatest impact stress of phonation. It is covered by stratified squamous epithelium, thus making this topmost layer much stiffer than the middle layer.The middle layer or lamina propria, comprising three layers of connective tissue: superficial (known as Reinke’s space) – consists of pliable, loose, fibrous connections;intermediate – consists primarily of elastic fibres;deep – consists of collagen fibres.The body or vocalis muscle, which can thicken, shorten and stiffen the vocal folds.
Anatomy as Applied to Transoral Surgery
John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford in Head & Neck Surgery Plastic Surgery, 2018
The internal laryngeal muscles move the laryngeal cartilages relative to one another, affecting tension and position of the true vocal cords. The thyroarytenoid muscle is a broad flat muscle lying deep to the free edge of the vocal ligament, originating from the thyroid prominence and cricothyroid ligament and inserting in to the vocal process and anterolateral surface of the arytenoid cartilage. The medial portion of the thyroarytenoid muscle is termed the vocalis muscle. The extrinsic portion of the thyroarytenoid muscle inserts anteriorly in to the anterior commissure as thick fibrous tissue known as Broyle’s ligament. The intrinsic muscles of the larynx are depicted in Figure 23.14.
Intraoperative Monitoring of External Branch of the Superior Laryngeal Nerve: Functional Identification, Motor Integrity, and its Role on Vocal Cord Function
Published in Journal of Investigative Surgery, 2018
A neural connection was found that exited the medial surface of the CTM and then entered into the lateral surface of the thyroarytenoid muscle; the human communicating nerve (HCN) [28]. Microdissection of 90 larynges obtained from necropsies established some form of anastomoses between the laryngeal nerves. Anastomosis between the external laryngeal and recurrent nerves appeared in 68% of cases as a connecting branch throughout the CTM [29]. The HCN has been reported to be present in 70% of humans [19]. In our series, 63.4% of EBSLNs of which stimulation created an amplitude may be included in this category of motor connection. Of these nerve branches, 67.5% of them created waveform amplitude between 100 and 200 µV. Therefore, a typical small response may be received on the endotracheal monitoring system through the HCN. On the contrary, we can suggest that patients who had no VC activity after EBSLN stimulation either may not have the HCN or did not create an amplitude of >100 µV. A higher amplitude (>300 µV) with stimulation of 12.6% of nerve branches revealed considerable motor innervations of the intrinsic laryngeal musculature via the EBSLN. A second source of motor innervation for the thyroarytenoid muscle other than the RLN, and communications between the laryngeal nerves has been suggested by clinical and experimental observations [26–28]. Our findings of recordable waveform amplitudes following EBSLN stimulation revealed some role of the SLN in the innervations of the intrinsic laryngeal musculature. These results increase the importance of protection of motor integrity of the EBSLN.
The effect of nasal septum deviation on voice aging
Published in Logopedics Phoniatrics Vocology, 2022
Ceren Ersoz Unlu, Ozlem Akkoca
Factors that affect aging of the voice are not well-defined. Physiological aging was shown to have a greater effect than chronological aging on the aging voice. Voice exercises may prevent laryngeal muscle atrophy; therefore, the aging process of the voice may be slower in people who perform voice exercises regularly such as professional voice users [31]. Regular aerobic exercise was shown to have a positive effect on the thyroarytenoid muscle in rats [32]. More research is required to determine the other factors that affect aging of the voice. To the best of our knowledge, this study is the only research to have analyzed the effect of NSD on voice aging.
Mobility of the arytenoid cartilage in glottic carcinoma: a CT image study
Published in Acta Oto-Laryngologica, 2023
Li Wang, Xi Zeng, Kai Li, Yunxin Lu, Dongxiao Nong
The full range of CT data in the anterior 2/3 group presented consistent static and motional conditions between the lesion and control sides. Lesions confined to the membranous portion of the cords are most commonly found in T1 or T2 stage glottic cancers (13/13 in this group), which does not lead to impaired VC mobility (Figure 6 (A, B and C)) unless carcinomatous invasion into 3/4 or more of thyroarytenoid muscle occurs [16,17]. The thyroarytenoid muscle is the earliest invaded intrinsic laryngeal muscle, while dysfunction of other intrinsic muscles happens in advanced T stages with posterior cricoid area or paraglottic invasion.
Related Knowledge Centers
- Aryepiglottic Fold
- Arytenoid Cartilage
- Rima Glottidis
- Thyroid Cartilage
- Vocal Cords
- Cricothyroid Ligament
- Thyroepiglottic Muscle