Background: Changes in voice quality are common in patients with different thyroid disorders.
Objectives: This work aims to identify subjective and objective voice changes in candidates for surgery for nonmalignant thyroid diseases to highlight its role in preoperative voice assessment and early detection of laryngeal disorder in those patients for further management.
Methods:  The patients' group included 60 consecutive patients with benign thyroid disease; their ages ranged between 19 and 65 years. Age and gender-matched control group included 30 healthy normal subjects. Both groups were subjected to clinical examination, modified GRBAS scale, Voice handicapped index, acoustic analysis, and flexible nasolaryngoscopy.
Results: Patients with thyroid disorders have significant dysphonia of mild to a moderate degree, as detected by APA in 38 % of patients. Acoustic analysis revealed altered jitter in 41% of patients and altered shimmer in 33%. Patients with abnormal thyroid hormone have more significant voice changes than patients with the euthyroid state.
Conclusion: The Auditory perceptual voice analysis and VHI revealed significant changes in overall voice quality and grade of dysphonia in patients with thyroid disease in a way that can be judged as a sensitive and reliable assessment tool being as acoustic analysis. Patients with abnormal thyroid hormone have a more chance to have voice disorders than patients with the euthyroid state. APA of voice must be a routine assessment for patients with benign thyroid disease, and patients with dysphonia have to be referred for voice specialists for further assessment.