Quantitative analysis of the anatomy of the epineurium of the canine recurrent laryngeal nerve.
The purpose of this investigation was to determine the amount of epineurium surrounding the recurrent laryngeal nerve (RLN) compared with a limb nerve, that to flexor hallicus longus (NFHL). Nerve samples were obtained from 10 adult dogs and studied using scanning electron microscopy and light microscopy to measure the relative proportion of epineurium and the relative proportions of adipose and collagenous tissue comprising the epineurium in both nerves. Significantly greater relative epineurial cross-sectional areas and adipose content were found in the RLN than in the NFHL. Based on observations on noncranial peripheral nerves, the findings indicate that the RLN is better protected against deformational forces associated with compression than stretching forces. The RLN may not be structured well for successful reinnervation after injury. The patterns observed for adipose tissue in RLN epineurial tissue appeared unique compared with those previously reported in peripheral nerves. The primary role associated with adipose tissue is to 'package' the nerve for protection. The RLN is considered to be a vital nerve in the body, as are other cranial nerves. The large proportions of adipose tissue in the epineurium may relate to the importance of protecting this nerve from injury. (+info)
Cranial and cervical nerve injuries after repeat carotid endarterectomy.
BACKGROUND AND PURPOSE: The incidence of cranial and/or cervical nerve injuries after primary carotid endarterectomy (CEA) ranges from 3% to 48%; however, the clinical outcome of these injuries after repeat CEA has not been thoroughly analyzed in the English-language medical literature. This prospective study analyzes the incidence and outcome of cranial nerve injuries after repeat CEA. PATIENTS AND METHODS: This study includes 89 consecutive patients who had repeat CEAs. Preoperative and postoperative cranial nerve evaluations were performed, including clinical examinations (neurologic) and direct laryngoscopy. Patients with vagal or glossopharyngeal nerve injuries also underwent comprehensive speech evaluations, video stroboscopy, fluoroscopy, and methylene blue testing for aspiration. Patients with postoperative cranial nerve injuries were followed up for a long time to assess their recovery. RESULTS: Twenty-five cranial and/or cervical nerve injuries were identified in 19 patients (21%). They included 8 hypoglossal nerves (9%), 11 vagal nerves or branches (12%) (6 recurrent laryngeal nerves [7%], 3 superior laryngeal nerves [3%], and 2 complex vagal nerves [2%]), 3 marginal mandibular nerves (3%), 2 greater auricular nerves (2%), and 1 glossopharyngeal nerve (1%). Twenty-two (88%) of these injuries were transient with a complete healing time ranging from 2 weeks to 28 months (18 of 22 injuries healed within 12 months). The remaining three injuries (12%) were permanent (1 recurrent laryngeal nerve, 1 glossopharyngeal nerve, and 1 complex vagal nerve injury). The recurrent laryngeal nerve injury had a longer healing time than the other cranial nerve injuries. CONCLUSIONS: Repeat CEA is associated with a high incidence of cranial and/or cervical nerve injuries, most of which are transient. However, some of these have a long healing time, and a few can be permanent with significant disability. (+info)
Injury to the superior laryngeal branch of the vagus during thyroidectomy: lesson or myth?
OBJECTIVE: To examine the historical evidence that the thyroidectomy performed on operatic soprano Amelita Galli-Curci was responsible for the abrupt termination of her career. SUMMARY BACKGROUND DATA: The superior laryngeal branch of the vagus nerve may be injured during thyroidectomy, producing vocal defects more subtle than those found after recurrent nerve injury. It is widely believed that Galli-Curci suffered superior laryngeal nerve injury during her thyroidectomy by Arnold Kegel, MD, in 1935, resulting in the termination of her career. METHODS: The authors examined contemporary press reviews after surgery, conducted interviews with colleagues and relatives of the surgeon, and compared the career of Galli-Curci with that of other singers. RESULTS: Evidence against the prevailing view is to be found in the fact that she continued to perform acceptably after surgery, her continued friendly relationship with the surgeon for years afterward, the absence of the typical effects of superior laryngeal nerve injury, and the presence of other explanations for the gradual decline in her vocal abilities (documentation of deterioration before surgery, physiologic changes in the larynx comparable to those found in most other famous sopranos who retire at about the same age or earlier, and the possible development of myxedema). CONCLUSIONS: The story should no longer be perpetuated in surgical textbooks and papers. (+info)
Prospective study of postoperative complications after total thyroidectomy for multinodular goiters by surgeons with experience in endocrine surgery.
OBJECTIVES: (1) To show that total thyroidectomy (TT) can be performed in multinodular goiter (MG) by surgeons with experience in endocrine surgery with a definitive complication rate of 1% or less; and (2) to analyze the risk factors for complications in these patients. SUMMARY BACKGROUND DATA: There is current controversy over the role of TT in the treatment of MG; although there are potential benefits, high rates of complications are not acceptable in surgery for a benign pathology. PATIENTS AND METHOD: A prospective study was conducted on 301 MGs meeting the following criteria: (1) bilateral MG; (2) no prior cervical surgery; (3) operation by surgeons with experience in endocrine surgery; (4) no associated parathyroid pathology; (5) no initial thoracic approach; and (6) minimum follow-up of 1 year. Age, sex, time of evolution, symptoms, cervical goiter grade, intrathoracic component, thyroid weight, and presence of associated carcinoma were analyzed as risk factors for complications. The chi test and a logistic regression analysis were applied. RESULTS: Complications were presented by 62 patients (21%), corresponding to 29 hypoparathyroidisms, 26 recurrent laryngeal nerve injuries, 4 lesions of the superior laryngeal nerve, 3 cervical hematomas, and 1 infection of the cervicotomy. The variables associated with the presence of these complications were hyperthyroidism (P = 0.0033), compressive symptoms (P = 0.0455), intrathoracic component (P = 0.0366), goiter grade (P = 0.0195), and weight of excised specimen (P = 0.0302); hyperthyroidism (relative risk [RR] 2.5) and intrathoracic component (RR 1.5) persisted as independent risk factors. Definitive complications appeared in 3 patients (1%), corresponding to 2 hypoparathyroidisms and 1 recurrent laryngeal nerve injury. Two cases corresponded to a toxic goiter, and the third to an intrathoracic goiter with compressive symptoms. CONCLUSION: In endocrine surgery units, TT can be performed for MG with a definitive complication rate of around 1%; the main independent risk factors for the development of complications are hyperthyroidism and goiter size. (+info)
Incidence of cranial nerve injuries after carotid eversion endarterectomy with a transverse skin incision under regional anaesthesia.
OBJECTIVES: The objective of this prospective study was to evaluate the incidence and distribution of cranial nerve injuries after carotid eversion endarterectomy (EEA) performed under regional anaesthesia using a transverse skin incision. PATIENTS AND METHODS: The study included 165 patients and 180 carotid arteries. All patients had a standard pre-operative assessment performed by a neurologist and ENT specialist. All carotid endarterectomies were performed by the eversion technique under regional anaesthesia. RESULTS: Ten cranial nerve injuries were observed. Seven patients had injuries of the marginal mandibular branch of the facial nerve, two patients had lesions of the hypoglossal nerve, and one patient had an injury of the recurrent laryngeal nerve. Eleven patients developed hoarseness without cranial nerve injury. Injuries of the marginal mandibular branch recovered after 3-8 months (mean 5.2 months). Both hypoglossal nerve injuries recovered after 4 months. The patient with the recurrent laryngeal palsy had no improvement after 19 months. Patients with hoarseness secondary to laryngeal haematoma recovered within 1 month. CONCLUSION: The incidence of cranial nerves injury after carotid EEA under regional anaesthesia is comparable to that reported for conventional carotid surgery. Postoperative hoarseness is most frequently due to laryngeal haematoma. (+info)
Surgical anatomy of the internal branch of the superior laryngeal nerve.
The internal branch of the superior laryngeal nerve (ibSLN) may be injured during anterior approaches to the cervical spine, resulting in loss of laryngeal cough reflex, and, in turn, the risk of aspiration pneumonia. Such a risk dictates the knowledge regarding anatomical details of this nerve. In this study, 24 ibSLN of 12 formaldehyde fixed adult male cadavers were used. Linear and angular parameters were measured using a Vernier caliper, with a sensitivity of 0.1 mm, and a 1 degrees goniometer. The diameter and the length of the ibSLN were measured as 2.1+/-0.2 mm and 57.2+/-7.7 mm, respectively. The ibSLN originates from the vagus nerve at the C1 level in 5 cases (20.83%), at the C2 level in 14 cases (58.34%), and at the C2-3 intervertebral disc level in 5 cases (20.83%) of the specimens. The distance between the origin of ibSLN and the bifurcation of carotid artery was 35.2+/-12.9 mm. The distance between the ibSLN and midline was 24.2+/-3.3 mm, 20.2+/-3.6 mm, and 15.9+/-4.3 mm at the level of C2-3, C3-4, and at the C4-5 intervertebral disc level, respectively. The angles of ibSLN were mean 19.6+/-2.6 degrees medially with sagittal plane, and 23.6+/-2.6 degrees anteriorly with coronal plane. At the area between the thyroid cartilage and the hyoid bone the ibSLN is the only nerve which traverses lateral to medial. It is accompanied by the superior laryngeal artery, a branch of the superior thyroid artery. The ibSLN is under the risk of injury as a result of cutting or compression of the blades of the retractor at this level. The morphometric data regarding the ibSLN, information regarding the distances between the nerve, and the other consistent structures may help us identify this nerve, and to avoid the nerve injury. (+info)
Transient palsy of peripheral cranial nerves following open heart surgery.
A 32-year-old man developed hoarseness of voice, inability to swallow and restricted movement of the tongue after open heart surgery. Peripheral injury of the cranial nerves IX, X and XII was suspected, and it was thought that the duration of the surgery together with the endotracheal tube cuff and trans-oesophageal echocardiography probe pressure, as well as the head and neck position might have been the causes of this complication. (+info)
The external laryngeal nerve in thyroid surgery: the 'no more neglected' nerve.
AIMS: To describe a novel surgical technique of 'lateralization' of superior pole to identify and save external branch of superior laryngeal nerve (EBSLN) during thyroidectomy. SETTINGS AND DESIGN: Prospective, nonrandomized at a tertiary care hospital in a specialized unit. MATERIAL AND METHODS: Over 30 months, 46 patients underwent thyroidectomy using technique of 1) 'Lateralization' of upper pole and dissection of avascular cricothyroid space 2) identification of EBSLN 3) skeletonization and individual ligation of superior thyroid vessels. Identified nerves were classified according to Cernea's classification. Outcomes were number of nerves identified, number of 'at risk' nerves' bilateral asymmetry and incidence of injury assessed by subjective interview and indirect laryngoscopy. RESULTS: Of the 78 dissected superior poles, nerves could be identified in 72 (92.31%). There were 22 (28.2%) type I, 42 (53.54%) IIa and 8 (10.25%) IIb 'at risk' nerves. In 32 patients with bilateral dissections, asymmetry of nerve was noted in 15%. Injury to nerve was not recorded in any of the patients. Average weight of glands was 69.59 g. Thyroidectomy was performed for benign disease in 28, malignancy in 4 and thyrotoxicosis in 14 patients. CONCLUSIONS: With technique of 'lateralization' and 'skeletonization and individual ligation of the superior vessels,' EBSLN identification increases and injury can be prevented. These results relate to the utilization of specific surgical technique and it is reasonable to expect that most surgeons, once familiar with the technique, should be able to achieve similar outcomes. (+info)