Causes of recurrent laryngeal nerve paralysis

Post-traumatic Delayed Bilateral Vocal Cord Paralysis Caused by Cervical Osteophytes: A Case Report

Vocal fold paralysis occurs when the function of the vagus nerve or its distal branch, the recurrent laryngeal nerve, is diminished or absent. Bilateral vocal fold paralysis can present with varying degrees of severity and is sometimes fatal. Cervical osteophytes are a rare cause of bilateral vocal fold paralysis, with only a few cases reported. A 68-year-old man was brought to the emergency department because of a disturbance in consciousness following a fall. A CT scan of the head showed multiple cranium and brain injuries, and the patient was treated conservatively by neurosurgery. The day after the injury, dysphagia and dysarthria appeared. On the third day of admission, both vocal cords were fixed bilaterally in the paramedian position, and the patient was nearly choking on sputum. A CT scan showed that the intracranial lesions gradually improved, but the vocal cord paralysis remained. A cervical CT scan was performed to investigate the cause of the vocal cord paralysis, which revealed that cervical vertebral osteophytes were compressing the tracheoesophageal groove and the glottis. The patient was transferred to the hospital for rehabilitation, although bilateral vocal cord paralysis remained. Although rare, clinicians need to be aware that cervical osteophytes can cause vocal fold paralysis, which may be manifested when combined with further trauma. It is also important to note that traumatic vocal cord paralysis can be delayed.

Etiology and presenting features of vocal cord paralysis: changing trends over the last two decades

Background

The study was performed to evaluate the changing trends in etiology and presenting features of vocal cord paralysis (VCP) from March 1998 to March 2020.

Methods

Patient’s record collected from hospital database and divided into two groups, from March 1998 to March 2009 and from April 2009 to March 2020, to evaluate the changing trends in etiology and presenting features.

Results

Total of 711 VCP patients, 80.3% with unilateral (UVCP) and 19.7% with bilateral vocal cord paralysis (BVCP) included. The commonest etiology was non-surgical (57.1%) for UVCP and surgical (55.7%) for BVCP. The commonest surgical etiology was thyroid and parathyroid surgery for both UVCP (16.6%) and BVCP (38.5%). The commonest non-surgical etiology was idiopathic for UVCP (23.1%) and malignancies for BVCP (13.6%). There was increase in surgical etiology for both UVCP (39.3 to 45.3%) and BVCP (51.2 to 57.7%), and decrease in non-surgical etiology for both UVCP (60.7 to 54.6%) and BVCP (48.8 to 42.3%). The change in voice was most common presenting features for both UVCP (69.2%) and BVCP (92.8%). The frequency of the presenting features was comparable, with decrease in the duration of symptom onset over the time period.

Conclusion

The most common etiology for UVCP was idiopathic, and for BVCP was thyroid and parathyroid surgery. For both, UVCP and BVCP there was increasing trend for surgical and decreasing trend for non-surgical etiology. The change in voice was the most common presenting complain, with decrease in duration of symptom onset over time period.

A Rare Cause of Ortner's Syndrome and a Case-Based Review of Literature

Ortner's syndrome refers to the compression of the recurrent laryngeal nerve by cardiovascular disorders of various etiologies. We describe a rare case of Ortner's syndrome caused by thoracic aorta aneurysm and a brief review of literature on this unusual cause of Ortner's syndrome. Hoarseness of voice due to the compression of recurrent laryngeal nerve by thoracic aorta aneurysm could be a harbinger of aneurysmal rupture.

Surgery for bilateral vocal fold paralysis: Systematic review and meta-analysis

Objectives

To determine the decannulation rate (DR) and revision surgery rate after surgery for bilateral vocal fold paralysis (BVFP).

Data Sources

Five databases (MEDLINE, PubMed, Embase, Web of Science, Scopus) were searched for the period 1908-2020.

Methods

The systematic literature review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data were pooled using a random-mixed-effects model. Randomized controlled trials and non-randomized studies (case-control, cohort, and case series) were included to assess DR and revision surgery rate after different surgical techniques for treatment of BVFP.

Results

The search yielded 857 publications, of which 102 with 2802 patients were included. DR after different types of surgery was: arytenoid abduction (DR 0.93, 95%-confidence interval [CI], 0.86-0.97), endolaryngeal arytenoidectomy (DR 0.92, 95%-CI, 0.86-0.96), external arytenoidectomy (DR 0.94; 95%-CI, 0.71-0.99), external arytenoidectomy and lateralisation (DR 0.87; 95%-CI, 0.73-0.94), laterofixation (DR 0.95; 95%-CI, 0.91-0.97), posterior cordectomy (DR 0.97, 95%-CI, 0.94-0.99), posterior cordectomy and arytenoidectomy (DR 0.98, 95%-CI, 0.93-0.99), posterior cordectomy and subtotal arytenoidectomy (DR 0.98, 95%-CI, 0.88-1.00), posterior cordotomy (DR 0.96, 95%-CI, 0.84-0.99), reinnervation (0.69, 95%-CI, 0.12-0.97), subtotal arytenoidectomy (DR 1.00, 95%-CI, 0.00-1.00) and transverse cordotomy (DR 1.0, 95%-CI, 0.00-1.00). No significant difference between subgroups for DR could be found (Q = 15.67, df = 11, p = 0.1540). The between-study heterogeneity was low (τ2 = 2.2627; τ = 1.5042; I2 = 0.0%). Studies were at high risk of bias.

Conclusion

BLVP is a rare disease and the study quality is insufficient. The existing studies suggest a publication bias and the literature review revealed that there is a lack of prospective controlled studies. There is a lack of standardized measures that takes into account both speech quality and respiratory function and allows adequate comparison of surgical methods.

Cardiovocal Syndrome Associated With Idiopathic Pulmonary Arterial Hypertension: A Case Report and Literature Review

Cardiovocal syndrome is left recurrent laryngeal nerve palsy associated with cardiovascular disease. Herein, we report a rare case of left recurrent laryngeal nerve palsy caused by idiopathic pulmonary arterial hypertension. A 40-year-old woman diagnosed with idiopathic pulmonary arterial hypertension was referred to our department for occult infection foci in the ear, nose, and throat (ENT). She had no apparent subjective symptoms in the ENT area, including hoarseness. Flexible laryngoscopy revealed left vocal cord paralysis, and contrast-enhanced computed tomography revealed dilatation of the pulmonary trunk, bilateral pulmonary arteries, and right ventricle, suggesting compression of the left recurrent laryngeal nerve. In our daily practice, when we encounter a left recurrent laryngeal nerve palsy that seems to be endogenous, cardiovascular lesions should be ruled out.

Diagnostic yield of computed tomography in the evaluation of unilateral vocal fold palsy

BACKGROUND

There is a paucity of Asian-based data regarding the diagnostic yield of computed tomography imaging in the initial assessment of idiopathic unilateral vocal fold palsy.

OBJECTIVES

To investigate the diagnostic yield of computed tomography in idiopathic unilateral vocal fold palsy cases in an Asian tertiary hospital, and to determine the causative pathologies and positive predictive factors.

METHOD

A retrospective chart review was conducted of patients (between 2010 and 2018) with a clinical diagnosis of idiopathic unilateral vocal fold palsy who underwent contrast-enhanced computed tomography of the neck and chest at Tan Tock Seng Hospital, Singapore.

RESULTS

The overall computed tomography diagnostic yield was 21 per cent, with malignancy accounting for 63.6 per cent of diagnoses. Degree of vocal fold weakness was the only significant predictor of positive computed tomography findings (11.5 per cent in vocal fold paresis vs 29.1 per cent in vocal fold paralysis, p = 0.025). None of the patients with negative computed tomography findings went on to develop disease after a mean follow up of 14.3 months.

CONCLUSION

Computed tomography is a useful initial investigation for idiopathic unilateral vocal fold palsy, particularly in cases with vocal fold paralysis.

Causes of Vocal Fold Paralysis

BACKGROUND

Vocal fold paralysis (VFP) can result from a variety of diseases or surgeries and has various causes. This study determined concurrent etiologies in patients who were treated in a teaching hospital (tertiary medical center).

METHODS

A retrospective review of medical records of patients with VFP from September 2010 to December 2019 was performed to determine the etiology. Patients with laryngeal/hypopharyngeal malignancies, those with incomplete examination and follow-up data were excluded from the study. During the follow-ups, cases involving recovery were also excluded.

RESULTS

One hundred and ninety-four patients with a determined etiology were included: 113 males and 81 females. Unilateral VFP was present in 178 patients, and 16 presented with bilateral VFP. The causes of unilateral VFP were surgical for 61.3%, neoplastic for 17.5%, idiopathic for 10.3%, traumatic for 1.5%, central for 4.7%, cardiovascular for 2%, radiation-induced for 1.5%, and inflammatory for 1%. Thyroidectomy was the most common surgery for unilateral VFP and was the cause for 54 patients. Lung cancer was responsible for 15 cases and was the most common neoplastic etiology of unilateral VFP. For those who presented with bilateral VFP, surgery was the most common cause and accounted for 56.3% of the incidences. In terms of gender, surgery was the most common cause for both sexes, accounting for 62 of 113 male patients and 57 of 81 female patients. Four cases recovered during the follow-ups and these were excluded.

CONCLUSION

Surgery and in particular, thyroidectomy, was the most common cause of VFP for these series. Central nervous system disorders were the cause of VFP (4.5%). Central nervous system disorders, especially cerebrovascular accidents that induced VFP, could not be neglected. Radiation-induced cranial nerve paralysis in the head and neck cancer was possible causes. The percentage for the causes of unilateral VFP, surgery increased and the percentage for neoplasm decreased for Taiwan.

Changes of TNF-α, PDGF and HA in nasal secretions and olfactory function of patients with chronic sinusitis before and after endoscopic sinus surgery

This study aimed to investigate the changes of tumor necrosis factor-α (TNF-α), platelet-derived factor (PDGF), hyaluronic acid (HA) in nasal secretions and olfactory function in patients with chronic sinusitis before and after endoscopic sinus surgery. A total of 94 patients with chronic sinusitis treated at Xiangyang No.1 People's Hospital, Hubei University of Medicine (Xiangyang, China) from May 2016 to April 2017 were randomly divided into the control and observation groups, with 47 patients in each group. The observation underwent endoscopic sinus surgery, while the control group were treated with traditional extranasal surgery. The treatment efficacy of the two groups were compared 3 months after the treatment. A self-designed symptom questionnaire was used to evaluate the symptom scores. Enzyme-linked immunosorbent assay (ELISA) was used to detect the TNF-α, PDGF and HA levels in nasal secretions. The olfactory function of the patients was evaluated by the standard T&T olfactometry test. The life quality before and after the treatment was compared by using the SNOT-20 questionnaire. The treatment efficacy of the observation group was significantly higher than that of the control group (P<0.05). Both groups showed improved symptom scores after the treatment, while improvement in the observation group was more obvious (P<0.05). The observation showed significantly lower TNF-α level than the control group (P<0.05). One, four and eight weeks after treatment, the levels of PDGF and HA were significantly higher in the observation group than in the control group (P<0.05). Both groups exhibited significantly improved olfactory function scores after treatment, and improvement in the observation group was more than that in the control group (P<0.05). After treatment, decreased scores of SNOT-20 in the observation group was more significant (P<0.05). Compared with traditional surgery, endoscopic surgery resulted in lighter postoperative inflammatory responses, better nasal mucosa repair, and more improved postoperative olfactory function.

Recurrent Nerve Palsy due to a Giant Vertebral Artery Aneurysm

Vertebral artery aneurysms are rare and challenging as they are usually asymptomatic and, therefore, often overlooked. We report the case of a 73-year-old man with a history of progressive dysphagia for 1 year. Computed tomography (CT) and computed tomography with angiography (CTA) of the cerebrum revealed a giant vertebral artery aneurysm compressing the medulla. Fiberoptic endoscopic evaluation of swallowing (FEES) revealed recurrent nerve paralysis. The patient was managed conservatively since the aneurysm was completely thrombosed.

Unilateral Vocal Cord Paralysis of a Great Jewish Opera Singer

George London was one of the most compelling vocal artists of the early twentieth century. At the age of 47, the great bass-baritone retired from singing. It has been suggested that the premature ending of his operatic career was due to unilateral vocal cord palsy (UVCP). When London retired, the common belief was that this UVCP was caused by viral hepatitis, although there is no evidence to support such an etiology. London's medical records eliminate the possible etiology of a neck neoplasm, and the long period of time between a heart attack he experienced and his diagnosis of UVCP makes a cardiovascular etiology an unlikely causative factor. London's relatively young age, the diagnosis of laryngitis prior to his UVCP, and the course of his disease indicate that the underlying cause of the termination of his singing career was post-viral neuropathy. This paper describes the clinical evidence related to London's vocal cord function and explores the possible causes for his UVCP, which apparently led to his early retirement.

One hundred years of external approach medialisation thyroplasty

It has been 100 years since Erwin Payr first developed an operation to improve the effects of a paralysed vocal fold, and operations based on this technique are still in use today. This technique, medialisation thyroplasty, aims to improve the symptoms caused by vocal fold palsy by realigning the lateralised vocal fold into the midline.

Whilst the effects of vocal fold palsy were recognised in antiquity, it was only with the development of indirect laryngoscopy in the late nineteenth century that the vocal fold paralysis could be identified as an aetiology for poor phonation and dysphagia. Payr, in 1915, was the first to perform a recognisable form of medialisation thyroplasty, which was further developed in the early twentieth century, but medialisation thyroplasty did not begin to be widely used until the development of the modern technique by Isshiki et al., in 1974.

Since then, medialisation thyroplasty has continued to be developed and is currently the most widely used technique for correcting the effects of vocal fold palsy. However, a wide array of therapeutic options is now available for vocal fold palsy and it is impossible to say whether or not medialisation thyroplasty will still be used in another 100 years.

Indications for Direct Laryngoscopic Examination of Vocal Cord Function Prior to Anterior Cervical Surgery

Recurrent laryngeal nerve palsy (RLNP) is among the most common complications in both thyroid surgeries and anterior approaches to the cervical spine, having both a diverse etiology and presentation. Most bilateral paresis, with subsequent devastating impact on patients, are due to failure to recognize unilateral recurrent laryngeal nerve paralysis and, although rare, are entirely preventable with appropriate history and screening. Recurrent laryngeal nerve palsy has been shown to present asymptomatically in as high as 32% of cases, which yields limitations on exclusively screening with physical examination. Based on the available literature, diagnosis of unilateral RLNP is the critical factor in preventing the occurrence of bilateral RLNP as the surgeon may elect to operate on the injured side to prevent bilateral paresis. Analysis of incidence rates shows postoperative development of unilateral RLNP is 13.1 (95% confidence interval [CI]: 6.1-28.1) and 13.90 (95% CI: 6.6-29.3) times more likely in anterior spine and thyroid surgery, respectively, in comparison with intubation. Currently, there is no consensus on when to order a preoperative laryngoscopic examination prior to anterior cervical spine surgery. The importance of patient history should be emphasized, as it is the basis for indications of preoperative laryngoscopy. Efforts to minimize postoperative complications must be made, especially when considering the rising rate of cervical fusion. This study presents a systematic review of the literature defining key causes of RLNP, with a probability-based protocol to indicate direct laryngoscopy prior to anterior cervical surgery as a screening tool in the prevention of bilateral RLNP.

Feasibility of vocal fold abduction and adduction assessment using cine-MRI

Objective

Determine feasibility of vocal fold (VF) abduction and adduction assessment by cine magnetic resonance imaging (cine-MRI)

Methods

Cine-MRI of the VF was performed on five healthy and nine unilateral VF paralysis (UVFP) participants using an axial gradient echo acquisition with temporal resolution of 0.7 s. VFs were continuously imaged with cine-MRI during a 10-s period of quiet respiration and phonation. Scanning was repeated twice within an individual session and then once again at a 1-week interval. Asymmetry of VF position during phonation (VF phonation asymmetry, VFPa) and respiration (VF respiration asymmetry, VFRa) was determined. Percentage reduction in total glottal area between respiration and phonation (VF abduction potential, VFAP) was derived to measure overall mobility. An un-paired t-test was used to compare differences between groups. Intra-session, inter-session and inter-reader repeatability of the quantitative metrics was evaluated using intraclass correlation coefficient (ICC).

Results

VF position asymmetry (VFPa and VFRa) was greater (p=0.012; p=0.001) and overall mobility (VFAP) was lower (p=0.008) in UVFP patients compared with healthy participants. ICC of repeatability of all metrics was good, ranged from 0.82 to 0.95 except for the inter-session VFPa (0.44).

Conclusion

Cine-MRI is feasible for assessing VF abduction and adduction. Derived quantitative metrics have good repeatability.

Key points

• Cine-MRI is used to assess vocal folds (VFs) mobility: abduction and adduction.

• New quantitative metrics are derived from VF position and abduction potential.

• Cine-MRI able to depict the difference between normal and abnormal VF mobility.

• Cine-MRI derived quantitative metrics have good repeatability.

Causes and imaging manifestations of paralysis of the recurrent laryngeal nerve

The vocal cords play a key role in the functions of the larynx. Their motor innervation depends on the recurrent laryngeal nerve (a branch of the tenth cranial nerve), which follows a long trajectory comprising intracranial, cervical, and mediastinal segments. Vocal cord paralysis usually manifests as dysphonia, the main symptom calling for CT study, the first-line imaging test to investigate the cause of the lesion. Patients are asymptomatic in a third of cases, so the incidental detection of signs of vocal cord paralysis in a CT study done for other reasons should prompt a search for a potentially severe occult lesion. This article aims to familiarize readers with the anatomy of the motor innervation of the glottis, the radiological presentation and most common causes of vocal cord paralysis, and conditions that can simulate vocal cord paralysis.

Ortner's syndrome: a case report and literature review

The authors report the case of a 55-year-old female, hypertensive, smoker patient presenting with dysphonia, dysphagia and persistent dry cough. Laryngoscopy diagnosed left vocal cord paralysis. Computed tomography demonstrated saccular aneurysm of the inferior wall of the aortic arch, stretching the left recurrent laryngeal nerve, a finding compatible with Ortner’s syndrome.

Preoperative vocal cord paralysis and its association with malignant thyroid disease and other pathological features

Background

Vocal cord paralysis (VCP) is found in both benign and malignant thyroid disease. This study was performed to determine if the presence of preoperative VCP predicts malignancy.

Methods

A retrospective analysis was performed on a cohort of 1923 consecutive patients undergoing thyroid surgery. The incidence of preoperative VCP was recorded. Patient and nodule characteristics were correlated with final pathology.

Results

1.3 % of our cohort was found to have preoperative VCP. Malignant pathology was discovered in 76 % of patients with preoperative VCP. Among these patients, 72 % had a left sided paralysis. 10.5 % of patients with preoperative VCP had perineural invasion (PNI) on final pathology, compared to 1.1 % of patients with normal VC function.

Conclusion

Preoperative VCP appears to be a strong, though not an absolute, indicator of malignancy. Most VCP were on the left side. Assessing for preoperative VCP is crucial in all patients who need thyroid surgery, as even benign nodules can be accompanied by preoperative vocal cord paralysis.

Diagnostic Yield of Computed Tomography in the Evaluation of Idiopathic Vocal Fold Paresis

Objective

To determine the diagnostic yield of computed tomography (CT) in establishing an etiology in patients with idiopathic unilateral vocal fold paresis (IUVFP). To determine the proportion of CT scans yielding incidental findings requiring further patient management.

Study Design

Case series with chart review.

Setting

Tertiary laryngology practice.

Subjects

Laryngology clinic patients under the care of the 2 senior authors.

Methods

All clinic patients were identified who had a diagnosis of IUVFP and underwent CT of the skull base to the upper mediastinum from 2004 to 2014. Demographic, historical, examination, and investigation data were extracted. CT reports and endoscopic recordings were reviewed. Patients were excluded if there were insufficient clinical findings recorded or if there was a known neurologic disorder, complete vocal fold immobility, or bilateral involvement.

Results

A total of 174 patients with IUVFP who had also undergone contrast-enhanced CT were identified. Of the 174 patients, 5 had a cause for their paresis identified on CT. This equated to a diagnostic yield of 2.9% (95% confidence interval, 0.94% to 6.6%). Of the 174 patients, 48 had other incidental lesions identified that required further follow-up, investigation, or treatment. This equated to an incidental yield of 27.6% (95% confidence interval, 21.1% to 34.9%).

Conclusion

This is the second and largest study to evaluate the diagnostic yield of CT in the evaluation of IUVFP. It demonstrates a low diagnostic yield and a high incidental yield. These findings suggest that the routine use of CT in the evaluation of idiopathic vocal fold paresis should be given careful consideration and that a tailored approach to investigation with good otolaryngologic follow-up is warranted.

Laryngeal Reinnervation Featuring Refined Nerve-Muscle Pedicle Implantation Evaluated via Electromyography and Use of Coronal Images

Objective

To evaluate the long-term efficacy of laryngeal reinnervation via refined nerve-muscle pedicle (NMP) flap implantation combined with arytenoid adduction to treat unilateral vocal fold paralysis (UVFP), employing laryngeal electromyography (LEMG), coronal imaging, and phonatory function assessment.

Study Design

Case series with chart review.

Setting

University hospital.

Subjects and Methods

We retrospectively reviewed 12 UVFP patients who underwent refined NMP implantation with arytenoid adduction. Videostroboscopy, phonatory functional analysis, LEMG, and coronal imaging were performed before and 2 years after surgery. In LEMG analysis, a 4-point scale was employed to grade motor unit (MU) recruitment: 4+ reflected no recruitment, 3+ greatly decreased recruitment, 2+ moderately decreased recruitment, and 1+ mildly decreased activity, associated with less than the full interference pattern. Coronal images were assessed in terms of differences in thickness and the vertical positions of the vocal folds.

Results

Phonatory function improved significantly after operation in all patients. In terms of LEMG findings, the preoperative MU recruitment scores were 1+ in no patients, 2+ in 4 patients, 3+ in 1 patient, and 4+ in 7 patients. Postoperative MU recruitment results were 1+ in 6 patients, 2+ in 5 patients, 3+ in 1 patient, and 4+ in no patients. Thinning of the affected fold during phonation was evident preoperatively in 9 of 10 patients. The affected and healthy folds were equal in volume in 4 of 9 patients postoperatively.

Conclusion

The LEMG findings and coronal imaging suggest that NMP implantation may have enabled successful reinnervation of the laryngeal muscles of UVFP patients.

Vocal cord paralysis: anatomy, imaging and pathology

Vocal cord paralysis (VCP) can be caused by any process that interferes with the normal function of the vagal nerves or recurrent laryngeal nerves. It may be a first sign of extensive and severe pathology. Radiologists must therefore be able to recognise the imaging findings of VCP and know the course of the vagal and recurrent laryngeal nerves. This review focuses on the anatomy and imaging evaluation of these nerves and thereby the possible sites for pathology causing VCP. The imaging characteristics and imaging mimics of VCP are discussed and cases from daily practice illustrating causes of VCP are presented.

• Vocal cord paralysis may be the first presentation of severe pathology.

• Radiologists must be aware of imaging characteristics and mimics of vocal cord paralysis.

• Lesions along the vagal nerves and recurrent laryngeal nerves can cause vocal cord paralysis.

Influence of Superior Laryngeal Nerve Injury on Glottal Configuration/Function of Thyroidectomy-Induced Unilateral Vocal Fold Paralysis

Objective

Recurrent laryngeal nerve (RLN) injury may induce unilateral vocal fold paralysis (UVFP). During thyroidectomy, the most common cause of UVFP, the superior laryngeal nerve (SLN), is also at risk of injury. In the literature, the influence of SLN injury on glottal configuration and function in patients with UVFP remains controversial. The present study investigates SLN injury influence on glottal configuration and function in patients with UVFP after thyroidectomy.

Study Design

Prospective controlled study.

Setting

Tertiary medical center.

Subjects and Methods

The SLN and RLN function of 34 patients with UVFP after thyroidectomy was determined by laryngeal electromyography. The subjects were dichotomized into the isolated RLN injury group (n = 26) or the concurrent SLN/RLN injury group (n = 8). We evaluated glottal angle and paralyzed vocal fold shape during inspiration, normalized glottal gap area, and glottal shape during phonation. The glottal function measurements included voice acoustic and aerodynamic analyses and the Voice Handicap Index. The aforementioned parameters of the RLN and concurrent SLN/RLN injury groups were compared.

Results

There were no statistical differences in glottal configuration such as glottal angle, paralyzed vocal fold shape, normalized glottal gap area, and glottal shape between the RLN and concurrent SLN/RLN injury groups. There were also no significant differences in other glottal function analyses including fundamental frequency, mean airflow rate, phonation quotient, maximal phonation time, and Voice Handicap Index.

Conclusion

In the present study, we did not find any evidence that SLN injury could significantly influence the glottal configuration and function in patients with UVFP.

Intraoperative recurrent laryngeal nerve monitoring: a useful method for patients with esophageal cancer

It is well accepted that recurrent laryngeal nerve paralysis is a severe complication of esophagectomy or lymphadenectomy performed adjacent to the recurrent laryngeal nerves. Herein, determination of the effectiveness of implementing continuous recurrent laryngeal nerve monitoring to reduce the incidence of recurrent laryngeal nerve paralysis after esophagectomy was sought. A total of 115 patients diagnosed with esophageal cancer were enrolled in the thoracic section of the Tangdu Hospital of the Fourth Military Medical University from April 2008 to April 2009. Clinical parameters of patients, the morbidity, and the mortality following esophageal resection were recorded and compared. After the surgery, a 2-year follow up was completed. It was found that recurrent laryngeal nerve paralysis and postoperative pneumonia were more frequently diagnosed in the patients that did not receive continuous recurrent laryngeal nerve monitoring (6/61 vs. 0/54). Furthermore, positive mediastinal lymph nodes (P = 0.015), total mediastinal lymph nodes (P < 0.001), positive total lymph nodes (P = 0.027), and total lymph nodes (P < 0.001) were more often surgically removed in the patients with continuous recurrent laryngeal nerve monitoring. These patients also had a higher 2-year survival rate (P = 0.038) after surgery. It was concluded that continuous intraoperative recurrent laryngeal nerve monitoring is technically safe and effectively identifies the recurrent laryngeal nerves. This may be a helpful method for decreasing the incidence of recurrent laryngeal nerve paralysis and postoperative pneumonia, and for improving the efficiency of lymphadenectomy.

Vocal cord paralysis and its etiologies: a prospective study

Introduction: Vocal cord paralysis is a common symptom of numerous diseases and it may be due to neurogenic or mechanical fixation of the cords. Paralysis of the vocal cords is just a symptom of underlying disease in some cases; so, clinical diagnosis of the underlying cause leading to paralysis of the vocal cords is important. This study evaluates the causes of vocal cord paralysis.

Methods: In a prospective study, 45 patients with paralyzed vocal cord diagnosis were examined by tests such as examination of the pharynx, larynx, esophagus, thyroid, cervical, lung, and mediastinum, brain and heart by diagnostic imaging to investigate the cause vocal cord paralysis. The study was ended by diagnosing the reason of vocal cord paralysis at each stage of the examination and the clinical studies.

Results: The mean duration of symptoms was 18.95±6.50 months. The reason for referral was phonation changes (97.8%) and aspiration (37.8%) in the subjects. There was bilateral paralysis in 6.82%, left paralysis in 56.82% and right in 63.36% of subjects. The type of vocal cord placement was midline in 52.8%, paramedian in 44.4% and lateral in 2.8% of the subjects. The causes of vocal cords paralysis were idiopathic paralysis (31.11%), tumors (31.11%), surgery (28.89%), trauma, brain problems, systemic disease and other causes (2.2%).

Conclusion: An integrated diagnostic and treatment program is necessary for patients with vocal cord paralysis. Possibility of malignancy should be excluded before marking idiopathic reason to vocal cord paralysis.

Acquired unilateral vocal fold paralysis: retrospective analysis of a single institutional experience

Background:

Vocal cord paralysis continues to be an important issue in laryngology and is considered as a sign of underlying disease; the etiologies of this problem are varied and changing.

Aims:

The study was to carry out a retrospective analysis of patients with unilateral vocal fold paralysis diagnosed.

Materials and Methods:

The medical records of 53 patients diagnosed and treated for unilateral vocal fold paralysis were studied retrospectively. Data regarding age, sex, duration of symptoms, etiology, and side of paralysis were recorded.

Results:

Out of the 53 cases, 36 were females and 17 males with a ratio of 2.1:1. The age of the patients ranged from 17-75 years. In 18.9% the cause was idiopathic. Surgical trauma (iatrogenic) problems was the most encountered etiology (66%), others included malignancy (non laryngeal) (7.5%), central (3.8%), external neck trauma (1.9%) and radiation therapy 1.9%. Thyroid surgery was the most commonly reported neck surgery in 50.9%.

Conclusions:

Thyroidectomy continues to be the single most common surgical procedure responsible for unilateral vocal cord paralysis. For this reason, routine pre and postoperative laryngoscopy should be considered in all patients undergoing surgeries with a potential risk for recurrent nerve paralysis to reduce the postoperative morbidity.

Developmental changes in the connective tissues of the porcine recurrent laryngeal nerve

The recurrent laryngeal nerve (RLN) branches from the vagus cranial nerve to innervate structures important for voicing and swallowing. Damage to this nerve, commonly associated with surgery or idiopathic etiologies that largely occur with aging, results in impaired voicing and swallowing (Myssiorek, 2004). Sunderland proposed a model of peripheral nerve damage whereby a nerve's ability to resist damage from stretch and compression is determined by the quantity and composition of its epineurial connective tissues (Sunderland, 1951). Thus, it would be expected that epineurium differs depending upon the forces imposed on a nerve within its anatomical setting. The purpose of this study was to investigate RLN epineurium quantity and composition with development. A porcine model (piglet vs. juvenile) was used because of the similarity between porcine and human laryngeal innervation, anatomy and function. The entire RLN was excised bilaterally, and stereological methods were used to quantify the composition of epineurial connective tissues. Compared with the piglet, the juvenile pig RLN was double the diameter. While the piglet had no differences in the percentage of epineurial collagen and adipose between proximal and distal segments of both sides of the RLN, the juvenile pig had a greater percentage of collagen in the proximal segment of both sides of the RLN and a greater percentage of adipose in the distal segment of the left RLN compared with the proximal segment. In addition, unlike the piglet, the juvenile pig had a greater number of fascicles in the proximal than distal segment of the RLN, regardless of nerve side. These findings are consistent with predicted patterns associated with the different anatomical settings of the left and right RLN, show that the RLN changes with age, and support Sunderland's model.

Vocal cord paralysis following orthognathic surgery intubation

The incidence of recurrent laryngeal nerve paralysis following short-term oro-endotracheal intubation for any surgical procedure is very rare. The diagnosis becomes very difficult if the surgical procedure may alter the vocal characteristics following surgery. We report a case of a 24 year-old healthy male patient who developed prolonged hoarseness which developed after having undergone a bimaxillary orthognathic surgical procedure. Following surgery, the patient's complaints of hoarseness and mild coughing on taking thin liquids were investigated with the assistance of the otolarynology voice department. A flexible fiberoptic laryngoscopy and videostroboscopy showed a partial paralysis of the left vocal cord suggesting damage to the left recurrent laryngeal nerve. The recovery was gradual and resolved without any intervention in approximately 6 weeks. Prolonged change or loss of voice quality following an orthognathic surgical procedure, as discussed in this case, when associated with difficulty in swallowing thin or thick liquids warrants a thorough investigation and can be managed at times with observation alone.

Cardiovocal Syndrome (Ortner's Syndrome) Associated with Chronic Thromboembolic Pulmonary Hypertension and Giant Pulmonary Artery Aneurysm: Case Report and Review of the Literature

Cardiovocal syndrome or Ortner's syndrome is hoarseness due to left recurrent laryngeal nerve palsy caused by mechanical affection of the nerve from enlarged cardiovascular structures. Chronic thromboembolic pulmonary hypertension is extremely rarely found to cause this syndrome. We describe a case of a 56-year-old patient with sudden onset of hoarseness. The patient had known long standing severe pulmonary hypertension. Fiberoptic laryngoscopy showed left vocal cord palsy. Computed tomography of the neck and chest revealed extensive enlargement of the pulmonary arteries and excluded a malignant tumor. The diagnosis of cardiovocal syndrome was retained. It is important for the radiologist to be aware of this possible etiology causing left recurrent laryngeal nerve palsy and to understand its mechanism.

Clinico-etiolological study of vocal cord paralysis

The purpose of this study was to identify patients of vocal cord paralysis and to establish an etiological diagnosis. Patients with vocal cord paralysis have been followed prospectively at a tertiary referral center. 120 patients identified with vocal cord paralysis by laryngeal endoscopy were evaluated clinically, radiologically and pathologically to make an etiological diagnosis. Those patients in whom no cause was found, a CT scan from base of skull to thorax was done before labeling them as idiopathic. Most of the patients presented in 5th (26.67 %) and 6th (21.67 %) decade. Males out numbered females in the ratio 2.3:1.0. The most common symptom of vocal cord paralysis was change in voice (98.21 %). Bilateral vocal cord palsy was found in 6.67 % patients and unilateral vocal cord palsy was found in 93.33 % patients. Among patients of unilateral vocal cord paralysis left vocal cord was paralyzed in 69.64 % and right cord in 30.36 %. Malignant (34.16 %) causes accounted for largest number of patients followed by central (15.00 %) and idiopathic causes (14.16 %). VCP has got a variable etiology which varies with the laterality of the vocal cord involvement. Malignant causes predominated in our series, occurring in 34.16 %, followed by central and idiopathic causes.

Treatment of bilateral vocal cord paralysis following permanent recurrent laryngeal nerve injury

Bilateral vocal cord paralysis is a serious illness requiring emergency intervention to resolve the potentially life-threatening respiratory distress. Several surgical procedures were proposed to help improve the airway and to eliminate the tracheostoma in those patients with permanent paralysis. All the procedures have their own advantages and disadvantages. We conducted a retrospective study of 30 patients affected by bilateral vocal cord paralysis following total thyroidectomy. All the patients underwent total thyroidectomy for benign thyroid pathology. In 26 patients (86.6%), cord paralysis occurred during the perioperative stage; and in the remaining 4 cases (13.3%), it occurred within the following 6 months. We treated all these bilateral recurrent laryngeal nerve paralysis patients with arytenoidectomy alone in 5 patients and arytenoidectomy with concomitant true and false posterior cordectomy in the remaining 25 patients. Twenty-four of the 25 patients who underwent the combined procedures (96%) reported subjective respiratory improvement and were decannulated within 60 days, being able to return to their normal daily activities. This study demonstrates that arytenoidectomy associated with posterior cordectomy is a satisfactory surgical treatment of bilateral vocal cord paralysis because it leads to a considerable and stable enlargement of the breathing space.

[Clinical evaluation of patients with vocal cord palsy--rate and timing of phonation recovery by disease differences]

Vocal cord palsy (VCP) is common in otolaryngological clinics, as are postoperative patients with VCP at general and university hospitals. Although VCP treatment strategies have been discussed, decisions on treatment methods and timing are complicated by the spontaneous recovery exhibited by some patients. We studied clinical features of VCP patients and their histories. Subjects were 171 VCP patients seen at our phonation clinic during a 15-year period-18% of all phonation clinic cases. By gender, 69% were male and 31% were female, ranging in age from 4 to 89 (mean, 58) years. Some 18% were bilateral and 82% unilateral, with 71% of unilateral cases on the left. Postoperative VCP occurred in 59% of patients in common surgical procedures for esophageal and thyroid tumors. During follow-up, 58% spontaneously recovered phonation. Postintubation VCP had the best recovery at 82%. Half with phonation recovery had spontaneous recovery from VCP and the other half had compensation. Most VCP resolved within 1 year, but compensation occurred after 1 year, meaning that in treatment planning and explanation, to VCP should be considered curable within 1 year and compensation attained 1 year after VCP.

Etiology of vocal cord paralysis

OBJECTIVE

Vocal cord paralysis (VCP) is a sign of a certain underlying disease, a diagnosis which can be attributed to various causes. This study intends to analyze the contemporary etiology of VCP in a tertiary medical center.

MATERIALS AND METHODS

A retrospective review of medical records from June 2000 to December 2004 of hospitalized patients with VCP was done to determine the etiology.

RESULTS

Two hundred and ninety-one patients with a determined etiology were identified, consisting of 176 males and 115 females. Unilateral VCP was present in 259 patients, while 32 presented with bilateral VCP. The causes were surgical in 40.2%, neoplastic in 29.9%, idiopathic in 10.7%, traumatic in 8%, central in 3.8%, radiation-induced in 3.4%, inflammatory in 2%, cardiovascular in 1.7% and other causes in 0.3% of the cases. Thyroidectomy represented the most common surgery for VCP and was the cause in 57 patients. Lung cancer was responsible for 34 cases and was the most common neoplastic etiology. In males, neoplasm was the most common cause occurring in 63 of 176 males, whereas surgery was most frequent in 59 of 115 females.

CONCLUSION

Surgical trauma, mainly thyroidectomy, is the most common cause of VCP in hospitalized patients. The possibility of a neoplasm must be ruled out before VCP is labeled idiopathic. A benign thyroid tumor could also cause VCP. Besides, radiation-induced cranial nerve paralysis in head and neck cancer may play a significant role.

Classification of unilateral vocal fold paralysis by endoscopic digital high-speed recordings and inversion of a biomechanical model

Hoarseness in unilateral vocal fold paralysis is mainly due to irregular vocal fold vibrations caused by asymmetries within the larynx physiology. By means of a digital high-speed camera vocal fold oscillations can be observed in real-time. It is possible to extract the irregular vocal fold oscillations from the high-speed recordings using appropriate image processing techniques. An inversion procedure is developed which adjusts the parameters of a biomechanical model of the vocal folds to reproduce the irregular vocal fold oscillations. Within the inversion procedure a first parameter approximation is achieved through a knowledge-based algorithm. The final parameter optimization is performed using a genetic algorithm. The performance of the inversion procedure is evaluated using 430 synthetically generated data sets. The evaluation results comprise an error estimation of the inversion procedure and show the reliability of the algorithm. The inversion procedure is applied to 15 healthy voice subjects and 15 subjects suffering from unilateral vocal fold paralysis. The optimized parameter sets allow a classification of pathologic and healthy vocal fold oscillations. The classification may serve as a basis for therapy selection and quantification of therapy outcome in case of unilateral vocal fold paralysis.

Dysphagia and Hoarseness Associated with Painless Aortic Dissection: A Rare Case of Cardiovocal Syndrome

Cardiovocal syndrome (Ortner's syndrome) is characterized by left recurrent laryngeal nerve palsy due to cardiovascular disease, but in rare cases it can also be caused by aortic dissection. An 81-year-old man with hypertension was admitted to the hospital with aspiration pneumonia. He had been developing progressive dysphagia and hoarseness for several months before admission. A videofluoroscopic swallowing study showed supraglottic penetration with barium paste and liquid. Laryngoscopy and electromyography revealed left vocal cord palsy caused by left recurrent laryngeal neuropathy, and a contrast-enhanced chest CT revealed dissection of the aortic arch.

Recurrent laryngeal nerve paralysis: anatomy and etiology

Etiologies of adult vocal paralysis are varied by the site of the lesion as well as the extent and cause of the damage. Most large series point to surgery and neoplastic causes for recurrent nerve paralysis. A detailed history is important when working up a patient with this voice disorder. Knowledge of the anatomy of the head, neck, and chest as well as the mechanisms behind vocal fold paralysis is essential in the evaluation and treatment of recurrent nerve paralysis. Many of the surgical and traumatic causes of hoarseness are from compression type injuries. Recovery is dependent on the type, extent, and site of nerve lesion. Familiarity with this data allows the otolaryngologist to tailor management to suit each patient with vocal fold paralysis.

Granulomatous Inflammation and Nerve Necrosis in a Case of Apparent Idiopathic Vocal Fold Paralysis: Report of a Case

OBJECTIVES

We will present clinical and pathologic findings of the recurrent laryngeal nerve of a 54-year-old man with apparent idiopathic vocal fold paralysis and discuss clinical and scientific implications of these findings.

STUDY DESIGN

Our design is in the format of a case report with emphasis on the clinical, intraoperative, histologic, and neuropathologic findings, followed by a discussion of contemporary theories of idiopathic unilateral vocal fold immobility and the implications of our findings.

METHODS

A 54-year-old man presented with a 2-year history of unilateral vocal fold motion impairment (VFMI) after an upper respiratory infection. Radiographic and laboratory data revealed no organic cause. The patient clinically appeared to have a classical unilateral vocal fold paralysis and had previously undergone collagen injection and medialization thyroplasty, each with only temporary improvement of voice. We performed ansa cervicalis-recurrent laryngeal nerve anastomosis.

RESULTS

Intraoperative dissection revealed an indurated and thickened section of nerve approximately 15 mm in length, located at the beginning of the intralaryngeal segment, near the cricothyroid joint. Segments of this nerve were submitted for histologic evaluation, revealing necrosis with granulomatous inflammation. Postoperative electromyography and videostrobolaryngoscopy were consistent with successful reinnervation from the ansa procedure.

CONCLUSIONS

The diagnosis of "idiopathic VFMI" likely represents a number of distinct pathologic entities. This case highlights our lack of understanding of idiopathic VFMI and raises many important questions regarding our current theories of this diagnosis. The clinical and pathologic implications are discussed, and continued investigation is recommended.

External vocal fold medialization in patients with recurrent nerve paralysis following cardiothoracic surgery

OBJECTIVES

Recurrent laryngeal nerve injury is a possible complication following cardiothoracic surgery. Due to insufficient glottal closure, dysphonia and dysphagia with aspiration may occur. The purpose of the study was to outline the effect of vocal fold medialization thyroplasty on voice, swallowing and breathing impairments.

METHODS

Between 1999 and 2001, medialization thyroplasty using the titanium implant (TVFMI) according to Friedrich was performed in 14 patients with postoperative left-sided recurrent nerve paralysis (five female and nine male patients, mean age 64 years) by an external approach. Previous surgical procedures comprised six lobectomies (combined with resection and replacement of the subclavian artery in one case), two pneumonectomies, one resection of a schwannoma in the aortopulmonary window, two replacements of the descending aorta, one aortocoronary bypass procedure (with LIMA), and two esophageal resections using Akiyama technique, respectively. Before and after thyroplasty, the patients underwent an otolaryngological/phoniatric examination including videostroboscopy, voice sound analysis, voice range profile measurement, pulmonary function testing, and in selected cases videofluoroscopy of swallowing.

RESULTS

Following thyroplasty, all patients reported on subjective improvement of voice, swallowing and breathing functions. Videostroboscopy revealed an improved glottal closure (six complete, six with posterior gap). All voice related parameters (e.g. roughness, breathiness, hoarseness, maximum sound pressure levels of the singing and shouting voices) were significantly improved.

CONCLUSIONS

Due to potential risk of recurrent nerve alteration in left-sided intrathoracic procedures, a preoperative and postoperative laryngoscopic examination is recommended. The external medialization of the vocal folds can be regarded as an excellent method for improvement of voice, swallowing and breathing, in particular, when the quality of life is impaired due to persistent recurrent nerve paralysis.

Vocal cord palsy resulting from spontaneous carotid dissection

OBJECTIVES/HYPOTHESIS

Vocal cord palsy has a variety of causes, such as malignant tumors of the thyroid, lung, or upper mediastinum, aortic aneurysm, surgery of the thyroid, and infectious diseases.

STUDY DESIGN

Case report.

METHODS

A 43-year-old biologist had a holocephalic headache and right-sided neck pain for 1 day. Five days later, he developed paralysis of the right-side vocal cord. In addition, an angiotensin converting enzyme (ACE) inhibitor was administered because the patient had high systolic and diastolic blood pressures, which were formerly not known to the patient. Five days after admission, a temporary sensorimotor hemiparesis occurred.

RESULTS

Neurological examination revealed, in addition to the known paralysis of the right-side vocal cord, right-side palatoplegia, right-side hypoglossal nerve palsy, and mild dysphagia. Duplex sonography showed evidence of lumen narrowing of the right-side internal carotid artery caused by an hypoechogenic mural hematoma. Magnetic resonance imaging (0.5 T, Philips Gyroscan) revealed a circumscribed dissection of the right-side internal carotid artery from the carotid bifurcation to the petrosal segment. The diffusion-weighted magnetic resonance imaging scan of the brain also demonstrated multiple embolic ischemic lesions in the right hemisphere.

CONCLUSION

Internal carotid artery dissection must be included in the differential diagnosis of lower cranial nerve palsy and should be assessed by duplex ultrasonography and magnetic resonance imaging.