Voice changes may be the earliest signs in laryngeal cancer. We investigated whether automated voice signal analysis can be used to distinguish patients with laryngeal cancer from healthy subjects. We extracted features using the software package for speech analysis in phonetics (PRAAT) and calculated the Mel-frequency cepstral coefficients (MFCCs) from voice samples of a vowel sound of /a:/. The proposed method was tested with six algorithms: support vector machine (SVM), extreme gradient boosting (XGBoost), light gradient boosted machine (LGBM), artificial neural network (ANN), one-dimensional convolutional neural network (1D-CNN) and two-dimensional convolutional neural network (2D-CNN). Their performances were evaluated in terms of accuracy, sensitivity, and specificity. The result was compared with human performance. A total of four volunteers, two of whom were trained laryngologists, rated the same files. The 1D-CNN showed the highest accuracy of 85% and sensitivity and sensitivity and specificity levels of 78% and 93%. The two laryngologists achieved accuracy of 69.9% but sensitivity levels of 44%. Automated analysis of voice signals could differentiate subjects with laryngeal cancer from those of healthy subjects with higher diagnostic properties than those performed by the four volunteers.

Background and purpose: The corticobulbar tract is a potential neural pathway involved in swallowing. The frontal operculum, insular cortex, corona radiata and internal capsule, which are frequently involved in middle cerebral artery (MCA) strokes, are locations in which lesions cause dysphagia. However, it is unclear whether the locations are linked to the corticobulbar tract or whether corticobulbar tract integrity is associated with dysphagia severity. This study aimed to assess the association between corticobulbar tract integrity and dysphagia severity after MCA stroke. Methods: Thirty dysphagic patients after MCA stroke and 27 healthy controls were examined. Diffusion tensor imaging (DTI)-derived parameters of the corticobulbar tract were compared between patient and control groups. Next, patients were divided into mild and moderate-to-severe dysphagia groups, and DTI-derived parameters of the corticobulbar tract were compared between the subgroups. Logistic regression analysis was used to determine the association between corticobulbar tract integrity and dysphagia severity. Results: The tract volume (TV) of the affected corticobulbar tract was lower in dysphagic patients than in healthy controls (P < 0.001). According to dysphagia severity, TV of the unaffected corticobulbar tract was higher in the mild dysphagia group than in the moderate-to-severe dysphagia group (P = 0.012). TV of the unaffected corticobulbar tract was independently associated with dysphagia severity according to the logistic regression model (adjusted odds ratio 0.817, 95% confidence interval 0.683-0.976). Conclusions: The corticobulbar tract was affected after MCA stroke and may be associated with dysphagia. A higher corticobulbar TV in the unaffected hemisphere was indicative of better swallowing function in dysphagic patients after MCA stroke.

Introduction: Injection laryngoplasty is a common procedure for patients with vocal fold dysfunction, but the literature on its benefits has been mainly focused on those related to structural lesions or laryngeal nerve involvement. Stroke patients may be at increased risk of aspiration due to insufficient vocal fold motion. However, how injection laryngoplasty can be of benefit in stroke patients has not been reported yet. Patient concerns: Six chronic stroke patients with long-standing swallowing difficulties and who showed severe aspiration despite long-term swallowing rehabilitation. Diagnosis: Laryngoscope evaluation revealed insufficient glottic closure as the cause of aspiration. Interventions: Injection laryngoplasty was done per-orally under local anaesthesia with calcium hydroxylapatite (Radiesse Voice, 1–1.5 mL) in an office setting. Respiratory pressures and peak cough flows were assessed at baseline and at 2 weeks follow-up. Outcomes: At 2 weeks, the mean peak cough flow (Δ = +95.09 L/min) increased significantly after the procedure. The maximal expiratory (Δ = +18.40 cm H2O) and inspiratory (Δ = +20.20 cm H2O) pressures also improved, indicating that injection laryngoplasty was effective in augmenting respiratory and cough parameters. All cases showed improvement in the Functional Oral Intake Scale (Δ = +4). Feeding tubes were successfully removed. Conclusion: Injection laryngoplasty proved to be both successful and safe in improving glottic closure with immediate results in those who had failed to show a positive response after long-term swallowing rehabilitation. The positive and dramatic clinical outcomes were observed through changes in the coughing force. Our case series support the use of injection larygnoplasty as a powerful adjunctive treatment method to prevent aspiration pneumonia in post-stroke patients with vocal fold insufficiency. Pre- and post-injection peak cough flow changes may reflect improvement in glottic closure and indicate the safety of swallowing with reduced risk of aspiration.