Humans ; Muscular Dystrophy, Duchenne ; physiopathology ; therapy ; Respiratory Physiological Phenomena

The aim of this study was to investigate the factors affecting cough ability, and to compare the assisted cough methods in patients with Duchenne muscular dystrophy (DMD). A total seventy-one male patients with DMD were included in the study. The vital capacity (VC) and maximum insufflation capacity (MIC) were measured. The unassisted peak cough flow (UPCF) and three different techniques of assisted peak cough flow were evaluated. UPCF measurements were possible for all 71 subjects. But when performing the three different assisted cough techniques, peak cough flows (PCFs) could be obtained from only 51 subjects. The mean value of MICs (1801+/-780cc) was higher than that of VCs (1502+/-765cc) (p< 0.01). All three assisted cough methods showed a significantly higher value than the unassisted method (F=80.92, p< 0.01). The manual assisted PCF under MIC (MPCFmic) significantly exceeded those produced by manual assisted PCF (MPCF) or PCF under MIC (PCFmic). The positive correlation between the MIC, VC difference (MIC-VC), and the difference between PCFmic and UPCF (PCFmic-UPCF) was seen (r= 0.572, p< 0.01). The preservation of pulmonary compliance is important for the development of an effective cough as well as assisting the compression and expulsive phases. Thus, the clinical importance of the inspiratory phase and pulmonary compliance in assisting a cough should be emphasized.
Adolescent ; Child ; Cough/*physiopathology ; Humans ; Inspiratory Capacity ; *Lung Compliance ; Male ; Muscular Dystrophy, Duchenne/*physiopathology/*therapy ; Pulmonary Ventilation ; *Respiratory Therapy ; Vital Capacity

OBJECTIVE: To determine the feasibility of using T2 mapping as a quantitative method to longitudinally follow the disease activity in children with Duchenne muscular dystrophy (DMD) who are treated with steroids. MATERIALS AND METHODS: Eleven boys with DMD (age range: 5-14 years) underwent evaluation with the clinical functional score (CFS), and conventional pelvic MRI and T2 mapping before and during steroid therapy. The gluteus muscle inflammation and fatty infiltration were evaluated on conventional MRI. The histograms and mean T2 relaxation times were obtained from the T2 maps. The CFS, the conventional MRI findings and the T2 values were compared before and during steroid therapy. RESULTS: None of the patients showed interval change of their CFSs. On conventional MRI, none of the images showed muscle inflammation. During steroid treatment, two boys showed increased fatty infiltration on conventional MRI, and both had an increase of the mean T2 relaxation time (p < 0.05). The remaining nine boys had no increase in fatty infiltration. Of these, three showed an increased mean T2 relaxation time (p < 0.05), two showed no change and four showed a decreased mean T2 relaxation time (p < 0.05). CONCLUSION: T2 mapping is a feasible technique to evaluate the longitudinal muscle changes in those children who receive steroid therapy for DMD. The differences of the mean T2 relaxation time may reflect alterations in disease activity, and even when the conventional MRI and CFS remain stable.
Adolescent ; Anti-Inflammatory Agents/therapeutic use ; Buttocks ; Child ; Child, Preschool ; Feasibility Studies ; Follow-Up Studies ; Humans ; Longitudinal Studies ; Magnetic Resonance Imaging/*methods ; Male ; Muscle Strength/drug effects ; Muscle, Skeletal/*drug effects/*physiopathology ; Muscular Dystrophy, Duchenne/*drug therapy/*physiopathology ; Observer Variation ; Pregnenediones/therapeutic use ; Prospective Studies