Vocal fold paralysis as a sign of chest diseases: a 15-year retrospective study

Imaging Modalities for Identifying Causes of Vocal Fold Paralysis: A Systematic Review and Meta-Analysis

BACKGROUND

Vocal fold paralysis (VFP), involving one or both vocal folds, often indicates underlying pathologies. Identifying VFP causes is vital for excluding malignancies and focusing on treating the cause. While various imaging methods are used to investigate VFP causes, their detection abilities remain unclear. This study aims to assess the detection prevalence of different imaging techniques in determining the causes of VFP.

METHODS

In September 2023 a comprehensive search was conducted per the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines across multiple databases, including Web of Science, PubMed, Scopus, Cochrane CENTRAL, and EMBASE. Following the search, the retrieved studies were screened based on the predefined eligibility criteria. Data extraction from the included studies was carried out independently by two authors. Outcomes were analyzed using pooled proportions and 95% confidence intervals.

RESULTS

Our meta-analysis encompassed 14 studies with 1492 VFP patients included. Malignant causes for VFP identification were most prevalent in F-fluorodeoxyglucose Positron Emission Tomography (PET)/Computed Tomography (CT) (41.5%) followed by Magnetic resonance imaging (MRI) (40%), with CT being the lowest (17.1%). Conversely, benign causes had the highest prevalence in F-fluorodeoxyglucose PET/CT (10.8%), followed by MRI (6.7%) and CT (4%). In the VFP cause identification, MRI had the highest detection prevalence (58.1%), followed by CT (30.1%), and Ultra Sound (US) had the lowest (26.8%). In chest lesion detection, CT had the highest prevalence (17.6%), followed by Chest X-ray (CXR) (6.5%). Head lesions were detected with CT at a prevalence of 15%, while neck lesion detection showed CT prevalence at 38.9% and US at 20.6%.

CONCLUSION

Our study revealed varying prevalence rates for the identification of malignant and benign causes across different imaging modalities. MRI demonstrated the highest overall detection prevalence for VFP causes, while CT was most commonly used and had the highest prevalence for specific lesions detection in various regions. These findings provide valuable insights into the diagnostic utility of different imaging techniques in the evaluation of VFP.

Computed Tomography Measurements in Assessment of Idiopathic Vocal Fold Paralysis

OBJECTIVE

Our study aimed to both identify the incidence and clinical presentation of patients presenting with idiopathic vocal fold paralysis (IVFP). Secondarily we aimed to assess the radiographic findings of computed tomography (CT) studies along the course of the vagus and recurrent laryngeal nerves (RLN), specifically measuring for potential areas of compression at the skull base and mediastinum. We hypothesized that a proportion of patients diagnosed with IVFP would have significant differences in measurements when compared to age-gender matched controls on CT imaging.

STUDY DESIGN

Institutional review board approved retrospective cohort study METHODS: We assessed patients presenting to a tertiary voice care center between 2003 and 2019 with diagnosis of vocal fold paralysis. Data collected includes demographics, clinical exam findings, and CT measurements including dimensions at bilateral jugular foramen, aortopulmonary (AP) window and surrounding vascular structures. Statistical analysis was then performed using Pearson χ², and Mann Whitney U tests to determine differences variables of interest.

RESULTS

A total of 606 patients were reviewed. Of these patients 60 (9.9%) patients were determined to have IVFP. Left-sided VFP was seen more commonly in 78.3% (N = 47) of idiopathic patients. Our IVFP group had an overall higher incidence of cardiovascular disease [OR = 3.378, 95%CI 1.907-5.941, P < 0.001] compared to those with identified causes for paralysis. Specifically, IVFP patients showed a higher incidence of combined cardiovascular co-morbidities (P < 0.001), mitral valve stenosis (P = 0.007), pulmonary hypertension (P < 0.0001) and congestive heart failure (P < 0.001). When evaluating CT imaging, the AP window was mentioned in only 2 (3.3%) of our idiopathic patients CT reports. The IVFP cohort had a lower median AP window volume (P = 0.020) when compared to age-gender matched controls. This significantly smaller AP window volume was also seen when only left sided IVFP compared to both right-sided paralysis (P < 0.001) and age matched control patients (P < 0.001).

CONCLUSION

The significance of cardiovascular comorbidities combined with findings of statistically narrowed AP window may help provide an explanation of a subset of patients diagnosed with IVFP.

Extracellular matrix deformations of the porcine recurrent laryngeal nerve in response to hydrostatic pressure

Damage to the recurrent laryngeal nerve (RLN) caused by supraphysiological compression or tension imposed by adjacent tissue structures, such as the aorta, may contribute to onset of idiopathic unilateral vocal fold paralysis (iUVP) resulting in difficulty speaking, breathing, and swallowing. We previously demonstrated in adolescent pigs that the right RLN epineurium exhibits uniform composition of adipose tissue, with larger quantities along its length within the neck region in contrast to the left RLN that shows greater collagen composition in the thoracic region and greater quantities of adipose tissue in the neck region. In contrast, the epineurium in piglets was primarily composed of collagen tissue that remained uniform along the length of the left and right RLNs. Tensile testing of the left and right RLN in piglets and pigs showed associated differences in strain by RLN side and segment by age. The goal of this study was to investigate how external hydrostatic compression of the RLN affects the nerve's connective tissue and microstructure. RLN segments were harvested from the distal (cervical/neck) regions and proximal (subclavian for the right RLN, thoracic for the left RLN) regions from eight adolescent pigs and nine piglets. RLN segments were isolated and assessed under fluid compression to test hypotheses regarding epineurium composition and response to applied forces. Second harmonic generation (SHG) imaging of epineurial collagen was conducted at 0, 40, and 80 mmHg of compression. The cartesian strain tensor, principal strain (Eps1), and principal direction of the RLN collagen fibers were determined at each pressure step. Significantly larger values of the 1st principal strain occurred in the proximal segments of the pig left RLN when compared to the same segment in piglets (p = 0.001, pig = 0.0287 [IQR = 0.0161 - 0.0428], piglet = 0.0061 [IQR = 0.0033 - 0.0156]). Additionally, the median transverse strain Eyy) for the second pressure increment was larger in the right proximal segment of pigs compared to piglets (p < 0.001, pig = 0.0122 [IQR = 0.0033 - 0.0171], piglet = 0.0013 [IQR = 0.00001 - 0.0028]). Eyy values were significantly larger in the right proximal RLN versus the left proximal RLNs in pigs but not in piglets (p < 0.001). In contrast to piglets, histological analysis of pig RLN demonstrated increased axial alignment of epineurial and endoneurial collagen in response to compressive pressure. These findings support the hypothesis that the biomechanical response of the RLN to compressive pressure changed from being similar to being different between the right and left RLNs during development in the porcine model. Further investigation of these findings associated with age-related onset of idiopathic UVP may illuminate underlying etiologic mechanisms. STATEMENT OF SIGNIFICANCE: Damage to the recurrent laryngeal nerve (RLN) caused by compression imposed by the aorta may contribute to the onset of left-sided idiopathic unilateral vocal fold paralysis resulting in difficulty speaking, breathing, and swallowing. The goal of this study was to investigate how compression affects the connective tissue and microstructure of the RLN. We quantified the pressure induced deformation of the RLN using multiphoton imaging as a function of both location (proximal versus distal) and age (piglets, adolescent pigs). Our results demonstrate that the biomechanical response of the RLN to compression changes in the right versus left RLN throughout development, providing further evidence that the the left RLN is exposed to increasing dynamic loads with age.

A Self-Activated CNN Approach for Multi-Class Chest-Related COVID-19 Detection

Chest diseases can be dangerous and deadly. They include many chest infections such as pneumonia, asthma, edema, and, lately, COVID-19. COVID-19 has many similar symptoms compared to pneumonia, such as breathing hardness and chest burden. However, it is a challenging task to differentiate COVID-19 from other chest diseases. Several related studies proposed a computer-aided COVID-19 detection system for the single-class COVID-19 detection, which may be misleading due to similar symptoms of other chest diseases. This paper proposes a framework for the detection of 15 types of chest diseases, including the COVID-19 disease, via a chest X-ray modality. Two-way classification is performed in proposed Framework. First, a deep learning-based convolutional neural network (CNN) architecture with a soft-max classifier is proposed. Second, transfer learning is applied using fully-connected layer of proposed CNN that extracted deep features. The deep features are fed to the classical Machine Learning (ML) classification methods. However, the proposed framework improves the accuracy for COVID-19 detection and increases the predictability rates for other chest diseases. The experimental results show that the proposed framework, when compared to other state-of-the-art models for diagnosing COVID-19 and other chest diseases, is more robust, and the results are promising.

Sensitivity of chest X-ray for detecting lung cancer in people presenting with symptoms: a systematic review

BACKGROUND

Despite increasing use of computed tomography (CT), chest X-ray remains the first-line investigation for suspected lung cancer in primary care in the UK. No systematic review evidence exists as to the sensitivity of chest X-ray for detecting lung cancer in people presenting with symptoms.

AIM

To estimate the sensitivity of chest X-ray for detecting lung cancer in symptomatic people.

DESIGN AND SETTING

A systematic review was conducted to determine the sensitivity of chest X-ray for the detection of lung cancer.

METHOD

Databases including MEDLINE, EMBASE, and the Cochrane Library were searched; a grey literature search was also performed.

RESULTS

A total of 21 studies met the eligibility criteria. Almost all were of poor quality. Only one study had the diagnostic accuracy of chest X-ray as its primary objective. Most articles were case studies with a high risk of bias. Several were drawn from non-representative groups, for example, specific presentations, histological subtypes, or comorbidities. Only three studies had a low risk of bias. Two primary care studies reported sensitivities of 76.8% (95% confidence interval [CI] = 64.5 to 84.2%) and 79.3% (95% CI = 67.6 to 91.0%). One secondary care study reported a sensitivity of 79.7% (95% CI = 72.7 to 86.8%).

CONCLUSION

Though there is a paucity of evidence, the highest-quality studies suggest that the sensitivity of chest X-ray for symptomatic lung cancer is only 77% to 80%. GPs should consider if further investigation is necessary in high-risk patients who have had a negative chest X-ray.

Imaging Modalities in the Etiologic Evaluation of Unilateral Vocal Fold Paralysis

OBJECTIVE

This study aimed to investigate the roles of computed tomography (CT) and neck ultrasonography (US) in evaluating unilateral vocal fold paralysis (UVFP) of unknown etiology and to compare our results with those of other studies to assess the differences in etiology of UVFP.

METHODS

We investigated the medical records of 202 eligible patients with UVFP. In total, 168 underwent chest CT, 118 underwent neck CT, and 108 underwent head CT. One hundred and three patients were also evaluated with high-resolution neck US. The etiologic causes of UVFP were also determined.

RESULTS

Of the 202 eligible patients, the occult cause of the UVFP was determined in 96 patients (47.5%). Idiopathic causes were the most common etiologies (n = 106). In occult causes group, chest lesions were the most common diseases causing paralysis (52 cases) and included lung cancer (n = 28) and mediastinal malignancy (n = 8). More than half of the neck lesions were of thyroid origin. Of the 18 thyroid lesions, 12 were thyroid malignancies. Chest CT had an intermediate yield of 30.9% (52 of 168). Neck US had a diagnostic yield close to that of neck CT (26.2%).

CONCLUSION

UVFP may result mainly from idiopathic, lung cancer, mediastinal, and thyroid malignancies. The initial use of neck US as an alternative to CT may be advocated for the determination of diseases resulting in UVFP.

Routine Computed Tomography in the Evaluation of Vocal Fold Movement Impairment without an Apparent Cause

Objective

Routine computed tomography (CT) for vocal fold movement impairment (VFMI) without an apparent cause is common. However, given increased cancer risk associated with ionizing radiation exposure, our purpose is to evaluate the utility of routine scans for these patients.

Study Design

Retrospective case series.

Setting

Houston, Texas.

Subjects and Methods

A 5‐year review of patients with VFMI diagnosed at an academic institution was conducted. For patients without an apparent cause (eg, recent head, neck, or cardiothoracic surgery or known malignancy), CT head/neck and chest was performed to evaluate the recurrent laryngeal nerve course. Data included demographics, symptoms, radiography, and interventions. Statistical analyses were performed via χ2 analysis.

Results

Of 406 patients with VFMI, 47 (11%) patients had no apparent cause clinically. Routine CT revealed abnormalities in 10 (21%) patients, of which only 3 (6%) could account for VFMI: benign thyroid adenoma (1), papillary thyroid cancer (1), and an esophageal mass (1). The most common lesion detected involved the thyroid. Demographic data and symptom type were not significantly associated with detection of a VFMI‐attributable lesion on CT. Overall, routine CT did not identify a focal etiology in 94% patients with VFMI without an apparent cause.

Conclusion

Routine pan‐CT evaluation failed to reveal an etiology in 94% of patients with VFMI without an apparent cause. Patients may be subjected to health risks associated with radiation exposure without significant diagnostic benefit. Further studies should consider more judicious use of CT in the context of risk factors and safer imaging modalities as the initial diagnostic step.

Differences in the microstructure and biomechanical properties of the recurrent laryngeal nerve as a function of age and location

Idiopathic onset of unilateral vocal fold paralysis (UVP) is caused by damage to the recurrent laryngeal nerve (RLN) and results in difficulty speaking, breathing, and swallowing. This damage may occur in this nerve as it loops around the aortic arch, which is in a dynamic biomechanical environment. The goal of this study is to determine if the location-dependent biomechanical and microstructural properties of the RLN are different in piglets versus adolescent pigs. The neck/distal and thoracic/proximal (near the aortic arch) regions of the RLN from eight adolescent pigs and six piglets were isolated and mechanically assessed in uni-axial tension. Two-photon imaging (second harmonic) data were collected at 5%, 10%, and 15% strain during the mechanical test. The tangential modulus (TM) and the strain energy density (W) were determined at each level of strain. The mean mode of the preferred fiber angle and the full width at half maximum (FWHM, a measure of fiber splay) were calculated from the imaging data. We found significantly larger values of TM, W, and FWHM in the proximal segments of the left RLN when compared to the distal segments (18.51 MPa ± 1.22 versus 10.78 MPa ± 1.22, p < 0.001 for TM, 0.046 MPa ± 0.01 versus 0.026 MPa ± 0.01, p < 0.003 for W, 15.52 deg ± 1.00 versus 12.98 deg ± 1.00, p < 0.001 for FWHM). TM and W were larger in the left segments than the right (15.32 MPa ± 1.20 versus 11.80 MPa ± 1.20, p < 0.002 for TM, 0.038 MPa ± 0.01 versus 0.028 MPa ± 0.01, p < 0.0001 for W). W was larger in piglets when compared to adolescent pigs (0.042 MPa ± 0.01 versus 0.025 MPa ± 0.01, p < 0.04). The proximal region of the left porcine RLN is more stiff than the distal region and has a higher degree of fiber splay. The left RLN of the adolescent pigs also displayed a higher degree of strain stiffening than the right. These differences may develop as a result of the more dynamic environment the left RLN is in as it loops around the aortic arch.

A computational study of the role of the aortic arch in idiopathic unilateral vocal-fold paralysis

Unilateral vocal-fold paralysis (UVP) occurs when one of the vocal folds becomes paralyzed due to damage to the recurrent laryngeal nerve (RLN). Individuals with UVP experience problems with speaking, swallowing, and breathing. Nearly two-thirds of all cases of UVP is associated with impaired function of the left RLN, which branches from the vagus nerve within the thoracic cavity and loops around the aorta before ascending to the larynx within the neck. We hypothesize that this path predisposes the left RLN to a supraphysiological, biomechanical environment, contributing to onset of UVP. Specifically, this research focuses on the identification of the contribution of the aorta to onset of left-sided UVP. Important to this goal is determining the relative influence of the material properties of the RLN and the aorta in controlling the biomechanical environment of the RLN. Finite element analysis was used to estimate the stress and strain imposed on the left RLN as a function of the material properties and loading conditions. The peak stress and strain in the RLN were quantified as a function of RLN and aortic material properties and aortic blood pressure using Spearman rank correlation coefficients. The material properties of the aortic arch showed the strongest correlation with peak stress [ρ = -0.63, 95% confidence interval (CI), -1.00 to -0.25] and strain (ρ = -0.62, 95% CI, -0.99 to -0.24) in the RLN. Our results suggest an important role for the aorta in controlling the biomechanical environment of the RLN and potentially in the onset of left-sided UVP that is idiopathic.

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.

Recommendations on follow-up strategies for idiopathic vocal fold paralysis: evidence-based review

Introduction:

Vocal fold paralysis can be an early warning sign of serious extra-laryngeal pathology. Even if imaging investigations show no pathology, there is always concern about the emergence of new pathology in the future. There is currently no consensus on the best follow-up protocol for vocal fold paralysis patients with no abnormalities on investigation.

Methods:

Systematic review, using an Ovid and Medline database search of papers written in the English language and published in the last 20 years.

Results:

Eight relevant studies were identified. Not all of them were directly comparable. A narrative review of the studies is presented and conclusions are drawn.

Conclusion:

Current diagnostic modalities are sufficiently reliable and sensitive to diagnose any significant existing extra-laryngeal pathology. Thus, once initial investigation (including computed tomography) has concluded, no further follow up is necessary.

CT evaluation of vocal cord paralysis due to thoracic diseases: a 10-year retrospective study

PURPOSE

To discuss computed tomography (CT) evaluation of the etiology of vocal cord paralysis (VCP) due to thoracic diseases.

MATERIALS AND METHODS

From records from the past 10 years at our hospital, we retrospectively reviewed 115 cases of VCP that were evaluated with CT. Of these 115 cases, 36 patients (23 M, 13 F) had VCP due to a condition within the thoracic cavity. From these cases, we collected the following information: sex, age distribution, side of paralysis, symptom onset date, date of diagnosis, imaging, and primary disease. The etiology of VCP was determined using both historical information and diagnostic imaging. Imaging procedures included chest radiograph, CT of neck or chest, and esophagography or esophagoscopy.

RESULTS

Thirty-three of the 36 patients with thoracic disease had unilateral VCP (21 left, 12 right). Of the primary thoracic diseases, malignancy was the most common (19, 52.8%), with 18 of the 19 malignancies presenting with unilateral VCP. The detected malignant tumors in the chest consisted of thirteen lung cancers, three esophageal cancers, two metastatic tumors, and one mediastinal tumor. We also found other underlying etiologies of VCP, including one aortic arch aneurysm, five iatrogenic, six tuberculosis, one neurofibromatosis, three benign nodes, and one lung collapse. A chest radiograph failed to detect eight of the 19 primary malignancies detected on the CT. Nine patients with lung cancer developed VCP between follow-ups and four of them were diagnosed with a progression of malignancy upon CT evaluation of VCP.

CONCLUSION

CT is helpful for the early detection of primary malignancy or progression of malignancy between follow-ups. Moreover, it can reveal various non-malignant causes of VCP.

Biomechanical properties of recurrent laryngeal nerve in the piglet

Unilateral vocal fold paralysis (UVP) results from damage to the recurrent laryngeal nerve (RLN). The most common causes of UVP are associated with compromised RLN tissue. The purpose of this research was to investigate the biomechanical properties of piglet RLN and identify differences in these properties along its length and in between the left and right side. Quasi-static uniaxial tensile testing and isotropic constitutive modeling was performed on seven piglet RLNs. Stiffness and other biomechanical parameters were derived from these tests and compared from conducting two different statistical analysis for the between and within nerve comparisons. Results showed higher stiffness values in the left RLN segment than for the right. Descriptive data demonstrated a higher stiffness in RLN segments surrounding the aortic arch, indicating a more protective role of the extracellular matrix in these nerves. This research offers insight regarding the protective function of the RLN connective tissues and structural compromise due to its environment.

Palliative treatment of dysphonia and dysarthria

The focus of this article is the palliative treatment of a variety of dysphonic conditions. Symptomatic relief of hoarseness can be achieved by voice therapy, augmentative alternative communication modalities, and surgery. The causes of dysphonia addressed herein include amyotrophic lateral sclerosis, Parkinson's disease, multiple sclerosis, stroke, head and neck cancers requiring glossectomy or laryngectomy, unilateral vocal fold paralysis, and presbyphonia. Palliative treatment of dysphonia and voice disorders provides symptomatic relief but not a cure of the underlying disease state. For these patients there are a number of palliative interventions that can greatly improve their quality of life.

Chronic voice hoarseness: when is it an emergency?

We report a 68-year-old man with chronic voice hoarseness, who presented to the emergency room with left-sided chest and hypochondrial pain. Chest radiograph showed a large mediastinal mass confirmed to be a thoracic aortic aneurysm by an emergent computed tomography scan. Examination and investigations of a patient with voice hoarseness and chest pain should focus on looking out for dissecting or leaking aneurysms, which may be catastrophic if missed.