Background: Inclusion Body Myositis (IBM) is characterized by progressive muscle weakness, with dysphagia affecting 40-80% of patients. Weakness in the pharynx and tongue significantly contributes to dysphagia, which can occur at any disease stage. Patients often adapt to minor swallowing difficulties over time, while asymptomatic respiratory function impairment is also common. Its impact on patients‘ quality of life is profound, while aspiration pneumonia and respiratory complications are the most common causes of death. Therefore, monitoring for swallowing and respiratory complications is crucial in managing IBM. Imaging techniques, like ultrasound (US), offer potential as non-invasive tools for monitoring muscle changes. The US morphologic study of the tongue and respiratory muscles may provide valuable insights into disease processes. Objective: To evaluate dysphagia and respiratory impairment using US in conjunction with clinical analyses. Methods: We conducted a cross-sectional study involving ten IBM patients. We analyzed clinical and epidemiological data descriptively to characterize the patient population. Dysphagia assessment used the IBM Functional Rating Scale (IBM-FRS), and we categorized ventilatory restriction based on FVC measurements by spirometry. We examined the patients with B-mode ultrasound, evaluating the diaphragm, intercostals, and tongue muscles (digastrics, geniohyoid, and genioglossus) in the transverse plane. All examinations took place on the right side using a fixed preset. Muscle classification followed the Modified Heckmatt Scale (1=normal, 2=probably abnormal, 3=abnormal). Results: The study included ten IBM patients, with 4 males and 6 females, with a median age of 61.5 years and median duration of disease of 9 years. Dysphagia was present in 60% of the patients, who reported occasional choking. US findings of the tongue muscles showed that the genioglossus muscle was altered in all patients and the least altered muscle in the tongue was the geniohyoid. In terms of respiratory function, the FVC of the patients ranged from 25% to 93% of the predicted values, with a median FVC of 67.0%. Ventilatory restriction was observed in the following proportions: 33.3% normal, 11.1% mild, 33.3% moderate, 11.1% severe, and 11.1% very severe. US evaluation of the respiratory muscles revealed that the intercostal muscles and the diaphragm were normal in only 20% of the patients. Conclusion: Abnormalities in the genioglossus muscle were frequently observed in patients with dysphagia. Ventilatory restriction was commonly seen in patients with abnormalities in the respiratory muscles. US evaluation of the tongue and respiratory muscles can provide insight into disease processes and guide therapeutic decisions even in patients without complaints of dysphagia or difficulty breathing. This evaluation may serve as an objective assessment of treatment response in the future.
Moreira et al. (Mon,) studied this question.