Shembel Adrianna C, Morrison Robert A, McDowell Sarah, Smeltzer Julianna C, Crocker Caroline, Bell Crystal, Mau Ted
School of Behavioral and Brain Sciences, Department of Speech, Language, and Hearing, University of Texas at Dallas, Dallas, Texas; Department of Otolaryngology-Head and Neck, Voice Center, University of Texas Southwestern Medical Center, Dallas, Texas.
School of Behavioral and Brain Sciences, Department of Speech, Language, and Hearing, University of Texas at Dallas, Dallas, Texas.
J Voice. 2023 Oct 19. doi: 10.1016/j.jvoice.2023.06.011.
Supraglottic compression is thought to underlie vocal effort in patients with primary muscle tension dysphonia (pMTD). However, the relationship between supraglottic compression and vocal effort in this clinical population remains unclear. Gold standard laryngoscopic assessment metrics for supraglottic compression are also lacking. The goals of this study were to identify metrics proposed in the literature that could distinguish patients diagnosed with pMTD from typical voice users and determine their relationships to the vocal effort.
Flexible laryngeal endoscopy was performed on 50 participants (25 pMTD, 25 controls). The presence of supraglottic compression was characterized using a categorical (nominal) scale and severity was quantified on ordinal and continuous scales. The three laryngoscopic metrics were correlated with self-perceived ratings of vocal effort on a 100 mm visual analog scale.
Inter-rater reliability was strongest for the continuous scale (P's < 0.0001) compared to categorical (P's < 0.001) and ordinal (P's < 0.001) scales. The presence of different supraglottic compression patterns varied in both groups, and there were no significant group differences on categorical (P's > 0.05) scales. Mediolateral (M-L) supraglottic compression was significantly greater in the pMTD group (P < 0.0001), and anteroposterior (A-P) compression was significantly greater in the control group (P = 0.001) using continuous scales. There were no significant relationships between any of the three laryngoscopic metric types and vocal effort ratings (P's > 0.05), except for a significantly positive relationship between anterior-posterior compression on the ordinal scale and vocal effort in the control group (P = 0.047).
Continuous scales are reliable and valid for distinguishing individuals with pMTD from those without voice disorders, especially occupational voice users. M-L supraglottic compression may be a better indicator of pMTD than A-P compression. However, the poor correlation between supraglottic compression and vocal effort suggests that one may not influence the other. Future studies should focus on other mechanisms underlying vocal effort in patients with pMTD.
声门上压缩被认为是原发性肌肉紧张性发声障碍（pMTD）患者发声用力的基础。然而，在这一临床群体中，声门上压缩与发声用力之间的关系仍不明确。同时，也缺乏用于评估声门上压缩的金标准喉镜检查指标。本研究的目的是确定文献中提出的能够区分被诊断为pMTD的患者与正常嗓音使用者的指标，并确定它们与发声用力的关系。
对50名参与者（25名pMTD患者，25名对照者）进行了柔性喉镜检查。使用分类（名义）量表对声门上压缩的存在情况进行描述，并在有序和连续量表上对其严重程度进行量化。将三种喉镜检查指标与100毫米视觉模拟量表上的自我感知发声用力评分进行相关性分析。
与分类量表（P值<0.001）和有序量表（P值<0.001）相比，连续量表的评分者间信度最强（P值<0.0001）。两组中不同声门上压缩模式的存在情况各不相同，在分类量表上两组间无显著差异（P值>0.05）。使用连续量表时，pMTD组的左右（M-L）声门上压缩明显更大（P<0.0001），而对照组的前后（A-P）压缩明显更大（P=0.001）。除了有序量表上的前后压缩与对照组的发声用力之间存在显著正相关（P=0.047）外，三种喉镜检查指标类型中的任何一种与发声用力评分之间均无显著关系（P值>0.05）。
连续量表对于区分pMTD患者与无嗓音障碍者，尤其是职业用嗓者是可靠且有效的。左右声门上压缩可能比前后压缩更能作为pMTD的指标。然而，声门上压缩与发声用力之间的低相关性表明两者可能互不影响。未来的研究应关注pMTD患者发声用力的其他潜在机制。
