Upper airway obstruction in patients with endothoracic goiter enlargement: no relationship between flow-volume loops and radiological tests

Background: In about 16-85% of subjects with goiter, upper airway obstruction (UAO) is observed. This percentage is higher in patients affected by goiter with endothoracic enlargement. UAO is an indication for surgery. Visual analysis of flow-volume loops (FVL) are the best indicators for UAO, although various studies using clinical and radiological parameters have observed no correlation. Objective: To evaluate the presence of UAO in patients with endothoracic goiter enlargement and the relationship between the FVL with the observed symptoms and the measurements obtained by computed tomography (CT). Subjects: Subjects with endothoracic goiter enlargement participated in the study. Design: i) Symptom questionnaire (dysphagia, dyspnea, cough, oppression, dysphonia, and worsened symptoms when prone); ii) analysis: TSH and free thyroxine; iii) cervical ultrasound; iv) cervical-thoracic CT (measurements of area and diameter in the area of maximum stenosis and at 2 cm from the carina); v) chest radiography and vi) forced spirometry: visual analysis of FVL morphology and the maximum forced expiratory volume in 1 s (FEV1), forced expiratory flow at 50% vital capacity/forced inspiratory flow at 50% vital capacity and FEV1/peak expiratory flow parameters. Results: Fifty subjects participated in the study: 11 men/39 women, median age 73.8 years (43.76 88.43). UAO was diagnosed in 13 cases (26%, confidence interval: 14.6 40.3%) and 27 subjects (54%) presented symptoms suggesting goiter compression. No clinical or radiological variables showed the presence of UAO. Conclusions: The frequency of UAO in subjects affected by goiter with endothoracic enlargement was lower than that described for goiter patients, and there were no clinical or radiological indicators to establish its presence.