Laryngeal atresia: a detailed histologic study

Laryngeal atresia is a rare, life-threatening anomaly. A case is reported with histological analysis of the deformity. Although there are different theories of glottic development, all authors agree that the primitive glottis is occluded at one time by an epithelial plug. Laryngeal atresia is felt to represent a lack of recanalization of the embryonic larynx. Laryngeal embryology is reviewed and the various types of laryngeal atresia are compared to the stages of laryngeal development.     

原发性喉淀粉样变的临床分析

目的:探讨原发性喉淀粉样变的临床特点及诊治措施。方法:回顾性分析1996-2011年收治的5例原发性喉淀粉样变患者的临床资料并进行总结。患者均行手术切除病灶,其中4例行喉裂开喉肿物切除术,1例行支撑喉镜病灶切除,均未行放疗和糖皮质激素治疗。结果:5例患者均痊愈出院,其中2例出院后失访,可以随访到的3例患者目前均情况良好,未见复发。随访时间0.3～7.5年,平均3.3年。结论:原发性喉淀粉样变好发于中年人,发病部位最常见的是声带,其次为室带、会厌前间隙等。早期手术治疗是最重要的治疗方式,喉内镜及CT检查对该病的诊断有重要价值;病理组织活检特别是刚果红染色阳性是诊断该病最特异的依据。     

Lateral Thyrotomy Approach on the Paraglottic Space for Laryngocele Resection

Objective To report on the results of using a lateral thyrotomy approach on the paraglottic space to gain greater access for laryngocele resection under direct vision. Study Design A 26‐year prospective and retrospective study. The study was conducted on 10 adult patients (5 men and 5 women) who had laryngocele of varying size on the paraglottic space. Six of the patients had internal laryngocele and four had exteriorized laryngocele. Five laryngoceles were left‐sided, three were right‐sided, and two were bilateral. Methods A V‐shaped, full‐thickness thyroid lamina resection with the triangle base at the superior border and the apex at a point midway of the thyroid lamina vertical extent was performed. Results A V‐shaped lateral thyrotomy made exposure to the paraglottic space possible for direct submucosal laryngocele dissection. This approach has presented no complications to date. Postoperative minor edema or hematoma was found in the aryepiglottic and ventricular folds, but this disappeared within a few days. There was no recurrence; the minimum follow‐up was 1 year. Conclusion The triangular lateral thyrotomy approach provided access to the paraglottic space and superb visibility for resection of laryngocele of any size under direct vision, thus avoiding recurrence, morbidity, and complications.     

Useful landmarks in arytenoid adduction and laryngeal reinnervation surgery

OBJECTIVE: Knowledge of the location of the muscular process of the arytenoid cartilage and the recurrent laryngeal nerve is essential to performing a successful arytenoid adduction and laryngeal reinnervation surgery. We describe external landmarks useful in locating these structures. STUDY DESIGN: Cadaveric laryngeal dissection. METHODS: Posterior laryngeal dissection was performed in 16 human larynges. The position of the muscular process of the arytenoid was measured bilaterally relative to the inferior and superior borders of the thyroid lamina. The recurrent laryngeal nerve was followed distally from slightly below the level of the cricothyroid joint to its genu where its vertical course changes to an oblique intralaryngeal course. RESULTS: The muscular process of the arytenoid was usually found halfway between the roots of the superior and inferior cornu of the thyroid lamina. The recurrent laryngeal nerve was found just deep to the cricothyroid joint and lateral to the posterior cricoarytenoid muscle. There were no other nerves in this area. CONCLUSIONS: This study finds that the superior and inferior borders of the thyroid lamina are useful intraoperative landmarks to locate the muscular process of the arytenoid. The cricothyroid joint provides a good starting point to locate the recurrent laryngeal nerve, which can be identified slightly deeper between it and the posterior cricoarytenoid muscle.     

Laser in treatment of laryngeal amyloidosis

Amayloidosis is the extracellular deposition of the fibrinous protein amyloid in one or more body sites. Amyloidosis may broadly be classifed as either primary or secondary. Primary amyloidosis is idiopathic (56 %), whereas the secondary form is associated with a chronic inflammatory or infectious process (5%). Amyloidosis is also related to multiple myeloma (26%), senescence (5%) and where tumor like deposits occur in isolated organ without systemic involvement (8%). Laryngeal amyloidosis is a rare disease. Surgery has been the mainstay of treatment either endoscopicalfy or by an external neck approach. One case of laryngeal amyloidosis, treated with endolaryngeal microsurgery and carbon dioxide laser is presented with a follow up of 8 years.     

Laser in treatment of laryngeal amyloidosis: A case report

Amyloidosis is the extracellular deposition of the fibrinous protein amyloid in one or more body sites. Amyloidosis may broadly be classified as either primary or secondary. Primary amyloidosis is idiopathic (56%), whereas the secondary form is associated with a chronic inflammatory or infectious process (5%), Amyloidosis is also related to multiple myeloma (26%). senescence (5%) and where tumor like deposits occur in isolated organs without systemic involvement (8%). Laryngeal amyloidosis is a rare discase. Surgery has been the mainstay of treatment either endoscopically or by an external neck approach. One case of laryngeal amyloidosis, treated with endolaryngeal microsurgery and carbon dioxide laser is presented with a follow up of 8 years.     

A morphometric study of the laryngeal saccule and sinus

A morphometric study of 111 larynxs from both sexes was performed with the initial intention of assessing the incidence of asymptomatic laryngeal pouches. Certain basic measurements were made also to determine the dimensions of the laryngeal saccule and sinus relative to the height and width of the larynx in the two sexes. Asymptomatic pouches aere found in 2 patients, one from each sex and there was no obvious difference in the height of the saccule relative to the height of the larynx in the two sexes. Hoaever, since the male larynx was deeper in the anteroposterior plane relative to its height, the male saccule tended to be relatively shallower than the female.     

Laryngeal mask anesthesia with intraoperative laryngoscopy for identification of the recurrent laryngeal nerve during thyroidectomy

OBJECTIVES/HYPOTHESIS: A critical step in thyroidectomy involves definitive identification of the recurrent laryngeal nerve (RLN). Using the laryngeal mask airway, identification of the RLN can be facilitated by stimulation of the nerve while monitoring vocal cord movement with a fiberoptic laryngoscope. We present this technique as an effective and safe means to identify the RLN during thyroid surgery, with significant advantages over existing techniques in appropriately selected patients. STUDY DESIGN: Retrospective case series. METHODS: We performed thyroidectomy on 8 patients (13 RLN identifications) in which laryngeal mask airway anesthesia with fiberoptic laryngoscopy was used to identify the RLN. Results are reviewed with regard to postoperative vocal cord function, as well as intraoperative and postoperative courses with laryngeal mask airway anesthesia. RESULTS: In all 13 cases in which the RLN was sought, it was definitively identified by witnessing brisk vocal cord movement on a video screen with stimulation of the RLN. No patient had postoperative vocal cord paresis or paralysis. Overall recovery from laryngeal mask airway anesthesia was uneventful and had advantages when compared with general anesthesia with endotracheal intubation. CONCLUSIONS: Laryngeal mask airway anesthesia with intraoperative fiberoptic laryngoscopy to identify the RLN is effective and safe in carefully selected patients. Advantages include decreased postoperative throat discomfort, absence of coughing during emergence from anesthesia, and elimination of the possibility of vocal cord mobility impairment secondary to RLN ischemia from the endotracheal tube balloon. In addition, this technique is applicable in operations besides thyroid surgery, in which definitive identification of the RLN is indicated.     

Laryngomalacia and its treatment

OBJECTIVE: To determine 1) airway outcome of infants with laryngomalacia who do not undergo routine direct laryngoscopy (DL) and bronchoscopy (B), 2) the age at resolution of laryngomalacia, and, 3) outcome of supraglottoplasty as a function of the type of laryngomalacia and the presence of concomitant disease. STUDY DESIGN: Retrospective chart review. METHODS: The records of all infants diagnosed with laryngomalacia by flexible fiberoptic laryngoscopy (FFL) between 1990 and 1998 in the Department of Otolaryngology--Head and Neck Surgery, University of Iowa (Iowa City, IA) were reviewed. The type of laryngomalacia was designated by a new classification scheme (types 1-3) based on the site of supraglottic obstruction and the type of supraglottoplasty indicated, should the patient later require surgical intervention. The log rank test was used to compare age at resolution and outcome between types of laryngomalacia and between infants with isolated laryngomalacia versus those with additional congenital abnormalities and/or severe neurological compromise. RESULTS: The type of laryngomalacia was evident in 48 of the 58 charts reviewed and included type 1 (57%), type 2 (15%), type 3 (13%), or combined types (15%). Twenty percent had severe neurological compromise and/or multiple congenital anomalies. The median time to resolution of stridor in these patients was not significantly delayed when compared with infants who had isolated airway anomalies (36 and 72 wk, respectively, vs. 36 wk for isolated laryngomalacia; P<.4). Time to resolution did not correlate with the type of laryngomalacia. In 22 infants, clinical symptoms or findings suggested a synchronous airway lesion, and direct laryngoscopy and bronchoscopy were performed. In 11 infants, a second airway lesion was diagnosed (in four cases by FFL and in 7 cases by direct laryngoscopy and bronchoscopy). Complications did not arise in infants who did not undergo direct laryngoscopy and bronchoscopy. Eleven infants with severe laryngomalacia required surgical intervention. The success of supraglottoplasty did not correlate with the type of laryngomalacia or the presence of other congenital anomalies. CONCLUSIONS: Routine direct laryngoscopy and bronchoscopy as part of the evaluation of laryngomalacia are not warranted. Performing these procedures should be based on clinical and physical evidence of a concomitant airway lesion. In general, laryngomalacia will resolve within the first year of life, even in children with multiple congenital anomalies and/or severe neurological compromise. The proposed classification scheme is advantageous in that it is simple and correlates the site of obstruction with the surgical procedure most likely to effect a cure, should the patient require a supraglottoplasty. Surgical management is necessary in approximately 15% to 20% of affected infants.     

Autofluorescence endoscopy in the diagnosis of early laryngeal cancer and its precursor lesions

OBJECTIVES: Because early detection and preoperative assessment of laryngeal cancer and its precursor lesions are essential for curative and function-preserving surgical treatment, autofluorescence endoscopy has been developed to gain more information about the biologic character of these lesions. The aim of the present study is to investigate a high, representative number of patients and to evaluate the diagnostic potential and the limitations of this method. METHODS: In a prospective study, 127 patients were investigated during microlaryngoscopy. A total of 111 patients were suspected of having precancerous or cancerous lesions, 12 had benign lesions, and 4 patients had normal epithelium. Autofluorescence was induced by filtered blue light (380-460 nm) of a xenon short arc lamp and processed by a CCD camera system (D-light-AF system; Storz, Tuttlingen, Germany). Autofluorescence endoscopic images were immediately assessed for diagnosis, correlated to the dysplasia grading system and compared with the histopathologic findings. RESULTS: Normal laryngeal mucosa displayed a typical green fluorescence signal. Moderate and high epithelial dysplasia, carcinoma in situ, and invasive carcinoma showed a diminished green fluorescence. False-negative results (n = 2) were the result of extreme hyperkeratosis. False positive cases (n = 8) either showed mild dysplasia with inflammatory reactions or scarring of the vocal folds. In 105 of 111 cases (94.6%), we found concordant results (sensitivity, 97.3%; specificity, 83.8%). CONCLUSION: Autofluorescence endoscopy facilitates the detection and delineation of precancerous lesions, carcinoma in situ, and microinvasive cancer of the larynx more accurately than clinical observation alone. Scarring, marked hyperkeratosis, and inflammation can limit the predictive value of the method.     

喉返神经损伤后喉肌病理生理研究

目的：通过对犬喉返神经损伤及再生过程中喉肌电生理及其病理变化进行研究,探讨喉返神经不同损伤形式的病理生理改变及转归特点。方法：实验用犬20只（40侧）分为喉返神经完全损伤组（全切法）、不完全损伤组（结扎法、挫灭法、半切法）及对照组,造模成功后的即刻、1、3、6和12个月观察甲杓肌和环杓后肌肌电特征及组织病理学改变。结果：造模后即刻全切法及结扎法肌电为电静息,挫灭法和半切法存在部分正常单个运动单位（MUP）及振幅减小的MUP混合肌电。神经损伤后1～3个月可出现纤颤电位,不完全损伤组3～6个月出现再生电位。全切法诱发电位基本无法引出,结扎法和半切法早期无诱发电位,后期可以引出振幅减小的诱发电位,结扎法小于半切法;而挫灭法始终都可以引出诱发电位,振幅与对照组无显著性差异,诱发电位潜伏期呈现先延长后缩短的趋势。随着全切、结扎、半切、挫灭损伤程度不同,肌纤维平均直径及肌束直径逐渐增大,单位面积细胞核数逐渐减少。结论：不同损伤,肌电特征及声带运动状态呈动态变化,喉返神经的损伤程度依次为完全损伤、不完全损伤（结扎法、半切法、挫灭法）,喉肌电图检查是声带麻痹诊断和评估的重要方法。     

Function of the laryngeal mechanoreceptors during vocalization

OBJECTIVES/HYPOTHESIS: The objective was to compare the activity of superior laryngeal nerve mechanoreceptors based on a respiration-based classification protocol with activities found using a vocalization-based classification protocol in adult cats. STUDY DESIGN: Animal study. METHODS: In the first part of the experiment, single fiber action potentials from the internal branch of the superior laryngeal nerve were recorded in decerebrated cats using a respiration-based classification protocol to identify laryngeal mechanoreceptors as pressure, flow, and drive receptors, as described in the literature. A tracheal T-tube and a laryngeal mask airway were necessary modifications to perform this protocol. In the second part of the experiment, a vocalization-based classification protocol as described in the literature was used to classify the activity of the same fiber into the following groups: peak prephonatory, frequency-following, frequency-nonfollowing, inspiratory-modulated, or mixed. Vocalization was evoked by electrical stimulation of the midbrain in the region of the periaqueductal gray. RESULTS: In all, eight cats were used for the experiment. Data were obtained from only three cats for a total of five single fibers. Results from five cats were not obtained because of inability to phonate (in three cats) and inability to record from the superior laryngeal nerve (in two cats). We identified two flow receptors, a drive receptor, a frequency-following receptor, and a frequency-nonfollowing receptor. Both flow receptor fibers were almost silent during the phonation phase and reached the maximum activity after vocalization during the inspiratory phase. The drive receptor was active during all four airway maneuvers and was most active during tracheal occlusion. It also kept a high level of activity during the phonatory phase, suggesting a role in the modulation of vocalization and respiration. The next two receptors, a frequency-following and a frequency-nonfollowing receptor, were active only during the phonatory phase and were totally inactive during the airway maneuvers, suggesting a role only during the vocalization behavior. CONCLUSION: Because vocalization is an important stimulus for the activation of certain superior laryngeal nerve receptors, a classification protocol based on respiration alone is incomplete. Classification into pressure, flow, and drive receptors alone is not appropriate for the study of laryngeal receptors during vocalization. Some frequency-following and frequency-nonfollowing receptors may be active only during phonation and would otherwise be missed without vocalization stimuli.     

Autofluorescence spectroscopy in the differentiation of laryngeal epithelial lesions – preliminary results

Conclusions Autofluorescence spectroscopy may be a supporting tool for differential diagnosis of changes in laryngeal epithelium. Objectives Early detection and differential diagnosis of proliferative changes in the larynx are still a challenge for laryngologists. The aim of the study was to evaluate the autofluorescence spectroscopy technique to in vitro differential diagnosis of pathological changes in the epithelium of the larynx. Methods Forty-two patients aged 34–79 years were included in the study. The fifty-two tissue specimens, including 10 samples of cancerous lesion, 10 adjacent normal tissue, 10 chronic inflammation, eight cyst, three leukoplakia, four polyp, and seven Reinke’s edema, were obtained during laryngological procedures. All tissue samples were independently diagnosed histopathologically. The autofluorescence emission spectra at two excitation wavelengths, 290?nm and 370?nm, were measured for every sample studied. Results The autofluorescence signals of cancerous tissue samples at both excitations exhibited identical emission band shapes of much lower intensities at their maxima as compared to the adjacent healthy tissue samples studied. The autofluorescence spectra intensities of cancerous and normal tissues varied inter-individually. Evident differences in autofluorescence intensities and its band shapes of different pathological laryngeal changes at the 290?nm excitations were demonstrated.     

Acoustic and perceptual evaluation of laryngeal reinnervation by ansa cervicalis transfer

Objectives/Hypothesis: To evaluate the acoustic and perceptual results of laryngeal reinnervation with ansa cervicalis to recurrent laryngeal nerve anastomosis. Study Design: Retrospective study of voice samples from 12 patients with unilateral recurrent laryngeal nerve paralysis, treated with ansa cervicalis to recurrent laryngeal nerve anastomosis. Samples were recorded before surgery and at least 8 months after surgery. Methods: The samples were subjected to several acoustic analyses sensitive to paralytic dysphonia, including cepstral peak prominence, noise-to-harmonics ratio, and measures of frequency and amplitude perturbation. The voice samples from the patients were randomized with age- and sexmatched samples from normal subjects and judged by trained listeners for overall dysphonia, roughness, breathiness, asthenia, and strain. The preoperative and postoperative results were compared statistically, and the postoperative results were compared with the matched normal subjects. Results: As a group, the patients showed improvement (P < .05) in cepstral peak prominence, frequency perturbation, and perceptual judgments of overall dysphonia, breathiness, and asthenia. The best results occurred in patients with isolated vocal fold paralysis. The postoperative group as a whole did not improve to the level seen in matched normals. Suboptimal results were seen primarily in patients with untreated laryngeal or extralaryngeal pathology beyond the laryngeal paralysis. Conclusions: These data suggest that laryngeal reinnervation has the potential to bring about a return to normal or near-normal voice in patients with isolated unilateral vocal fold paralysis.