Hiệu quả của bài tập Tiếng Việt cho bệnh nhân liệt dây thần kinh quặt ngược một bên sau cắt tuyến giáp toàn bộ

Tỷ lệ phẫu thuật cắt tuyến giáp toàn bộ do ung thư tuyến giáp có xu hướng tăng dần, đi kèm với phẫu thuật này là những thay đổi về giọng sau phẫu thuật, đặc biệt là tổn thương dây thần kinh hồi quy sau phẫu thuật. Mục tiêu của nghiên cứu nhằm đánh giá hiệu quả của bài tập tiếng Việt trên những bệnh nhân liệt thần kinh thanh quản quặt ngược sau phẫu thuật cắt toàn bộ tuyến giáp. Nghiên cứu được tiến hành trên 60 bệnh nhân bị tổn thương dây thần kinh hồi quy sau phẫu thuật cắt toàn bộ tuyến giáp tại Bệnh viện Đại học Y Hà Nội, Bệnh viện Tai Mũi Họng Trung Ương, Bệnh viện K từ tháng 1/2015 đến tháng 1/2020. Đối tượng nghiên cứu được chia làm 2 nhóm: 30 người được can thiệp bằng bài tập và đánh giá chất lượng giọng của bài tập sau 03 tháng, 06 tháng và 12 tháng (nhóm 1) và 30 người khác theo dõi chất lượng giọng mà không có can thiệp gì thêm sau 03 tháng, 06 tháng và 12 tháng (nhóm 2). Chất lượng giọng được đánh giá bằng phần mềm phân tích âm PRAAT. Kết quả cho thấy ở nhóm 1: vận động của sụn phễu và dây thanh bên liệt cải thiện, không thấy hiện tượng teo cơ dây thanh, hai dây thanh khép kín hơn, các chỉ số: jitter, shimmer, noise-to-harmonic ratio (HNR) các nguyên âm (trầm, trung tính, cao), phụ âm, thanh điệu và tần số âm cơ bản (F0, F1, F2) đều cải thiện so với nhóm 2 (p < 0,005), khả năng kéo dài phát âm. Kết luận: Nhóm đối tượng liệt hồi quy sau cắt tuyến giáp toàn bộ nên được thực hiện bài tập phát âm.

Effects of Laryngeal Massage on Muscle Tension Dysphonia: A Systematic Review and Meta-Analysis

Background and Objectives This study was to investigate the voice quality and articulation effects of laryngeal massage on muscle tension dysphonia (MTD).Materials and Method A systematic review of articles published between January 2000 and December 2020 in Cochrane, PubMed, ScienceDirect, SpingerLink, ERIC, and Naver Academic was conducted. From the total of 2094 articles identified, 10 peer-reviewed articles were included in a meta-analysis. Mean effect sizes of the variables related to voice quality (jitter, shimmer, harmonic to noise ratio or noise to harmonic ratio, high-F0, low-I, cepstral peak prominence) and articulation (F1, F2, F1 slope, F2 slope) were calculated by Hedges’g.Results Meta-analysis of the selected articles showed that laryngeal massage had medium to large effects on all variables of voice quality and articulation except F0-high and F1 slope in the MTD patients.Conclusion This study provided comprehensive clinical evidence that it is highly desirable to apply laryngeal massage to MTD patients.

A Meta-Analysis of the Association Between the Voice Handicap Index and Objective Voice Analysis

Purpose Dysphonia can be evaluated by both patient-reported quality of life instruments and objective acoustic and aerodynamic analyses. However, less is known about the association between the two metrics. The goal of this study was to perform a meta-analysis of the correlation of the Voice Handicap Index (VHI-30) with the following objective parameters: fundamental frequency, jitter, shimmer, harmonics to noise ratio, noise to harmonic ratio, maximum phonation time, and the Dysphonia Severity Index. Method A literature search was performed in the PubMed, Scopus, and Cumulative Index of Nursing and Allied Health Literature databases. Inclusion criteria were subjects age 18 years and older with voice complaints and assessed by both VHI-30 and objective voice analysis. Results A literature search resulted in 1,297 unique articles, of which 310 underwent full-text review and 17 studies were included in quantitative analysis. Significant pooled correlation was observed for VHI-30 total with jitter (.301 [.177; .416]), shimmer (.255 [.162; .344]), noise to harmonic ratio (.200 [.111; .285]), maximum phonation time (−.227 [−.352; −.094]), and Dysphonia Severity Index (−.254[−.455; −.0286]). Significant correlations were observed in 4/7 objective parameters with the Physical subscale, 3/7 with the Functional subscale, and 2/7 with the Emotional subscale. All significant correlations were negligible (0–.3) or low (.3–.5). Conclusions Results from meta-analysis showed that correlations between objective voice parameters and the VHI-30 were negligible or low. Further study is needed to determine if correlations vary by patient demographics or specific pathology.

Experimental Analysis on the Transduction Coefficient of a Non-Linear Electromagnetic Energy Harvesting Device with Softening Stiffness

Nonlinear energy harvesting devices in the form of stiffness nonlinearity have emerged as among the effective solutions to overcome the performance limit of linear energy harvesting devices. However, up to now, researches on the nonlinear devices are only focusing on the ability to widen the bandwidth while the limit of employing linear transduction coefficient in a nonlinear system has yet to be heavily discussed. This paper investigates on the transduction coefficient for both linear and nonlinear systems of an electromagnetic energy harvesting device as a function of the excitation frequency. It is proven that the transduction coefficient of the nonlinear device is larger than its equivalent linear device, especially in the multi-stable solutions region. In common practice, the nonlinearity in the nonlinear system is considered weak, and its transduction coefficient is assumed to converge to the one produced by the linear system. The limits to which the transduction coefficient of a linear system can be employed on the nonlinear system were drawn based on the experimental analysis conducted on the proposed device. The device was designed to perform as a linear or nonlinear system, where the degree of nonlinearity was changed by varying the gap between the magnets. The limit of the transduction coefficient was determined from the analysis of the harmonic ratio. The results show that the linear transduction coefficient is valid to be employed to the nonlinear system when the harmonic ratio is less than five per cent at the multi-stable solutions region.

Recognition of pathological voices by Human Factor Cepstral Coefficients (HFCC)

Several tools have been introduced to achieve early detection of voice disorders. Among these tools are the human factor cepstral coefficients HFCC combined with prosodic parameters, the noise-harmonic ratio (NHR), the harmonic-noise ratio (HNR), analysis of trend fluctuations (DFA) and fundamental frequency (F0). These parameters are introduced and calculated in every frame. In this work, we used a variation of HFCC called equivalent rectangular bandwidth (ERB) to study the effects of HFCC on the classification of pathological voices. Using the HTK classifiers, the classification is carried out on two pathological databases, Massachusetts Eye and Ear Infirmary (MEEI) and Saarbruecken Voice Database (SVD). To assess the performance of the system, we used sensitivity and specificity.