Ultrasonographic Diaphragmatic Motion Analysis and Its Correlation With Pulmonary Function in Hemiplegic Stroke Patients

OBJECTIVE To evaluate diaphragmatic motion via M-mode ultrasonography and to correlate it with pulmonary function in stroke patients. METHODS This was a preliminary study comprised of ten stroke patients and sixteen healthy volunteers. The M-mode ultrasonographic probe was positioned in the subcostal anterior region of the abdomen for transverse scanning of the diaphragm during quiet breathing, voluntary sniffing, and deep breathing. We analyzed diaphragmatic motion and the relationship between diaphragmatic motion and pulmonary function. RESULTS All stroke patients had restrictive pulmonary dysfunction. Compared to that exhibited by control subjects, stroke patients exhibited a significant unilateral reduction in motion on the hemiplegic side, primarily during volitional breathing. Diaphragmatic excursion in right-hemiplegic patients was reduced on both sides compared to that in control subjects. However, diaphragmatic excursion was reduced only on the left side and increased on the right side in left-hemiplegic patients compared to that in control subjects. Left diaphragmatic motion during deep breathing correlated positively with forced vital capacity (rho=0.86, p=0.007) and forced expiratory volume in 1 second (rho=0.79, p=0.021). CONCLUSION Reductions in diaphragmatic motion and pulmonary function can occur in stroke patients. Thus, this should be assessed prior to the initiation of rehabilitation therapy, and M-mode ultrasonography can be used for this purpose. It is a non-invasive method providing quantitative information that is correlated with pulmonary function.