Diaphragmatic motion studied by m-mode ultrasonography: methods, reproducibility, and normal values.
BACKGROUND
Although diaphragmatic motion is readily studied by ultrasonography, the procedure remains poorly codified. The aim of this prospective study was to determine the reference values for diaphragmatic motion as recorded by M-mode ultrasonography.


METHODS
Two hundred ten healthy adult subjects (150 men, 60 women) were investigated. Both sides of the posterior diaphragm were identified, and M-mode was used to display the movement of the anatomical structures. Examinations were performed during quiet breathing, voluntary sniffing, and deep breathing. Diaphragmatic excursions were measured from the M-mode sonographic images. In addition, the reproducibility (inter- and intra-observer) was assessed.


RESULTS
Right and left diaphragmatic motions were successfully assessed during quiet breathing in all subjects. During voluntary sniffing, the measurement was always possible on the right side, and in 208 of 210 volunteers, on the left side. During deep breathing, an obscuration of the diaphragm by the descending lung was noted in subjects with marked diaphragmatic excursion. Consequently, right diaphragmatic excursion could be measured in 195 of 210 subjects, and left diaphragmatic excursion in only 45 subjects. Finally, normal values of both diaphragmatic excursions were determined. Since the excursions were larger in men than in women, the gender should be taken into account. The lower limit values were close to 0.9 cm for women and 1 cm for men during quiet breathing, 1.6 cm for women and 1.8 cm for men during voluntary sniffing, and 3.7 cm for women and 4.7 cm for men during deep breathing.


CONCLUSIONS
We demonstrated that M-mode ultrasonography is a reproducible method for assessing hemidiaphragmatic movement.
Boussuges
Alain
A
UMR MD 2, P2COE, Physiologie et Physiopathologie en conditions d'oxygénation extrêemes, Université de la Méditerranée et Institut de Médecine Navale du Service de Santé des Armées, Marseille, France. Electronic address: alain.boussuges@univmed.fr.
Gole
Yoann
Y
UMR MD 2, P2COE, Physiologie et Physiopathologie en conditions d'oxygénation extrêemes, Université de la Méditerranée et Institut de Médecine Navale du Service de Santé des Armées, Marseille, France.
Blanc
Philippe
P
UMR MD 2, P2COE, Physiologie et Physiopathologie en conditions d'oxygénation extrêemes, Université de la Méditerranée et Institut de Médecine Navale du Service de Santé des Armées, Marseille, France.
D000328:Adult; D000368:Aged; D000886:Anthropometry; D015331:Cohort Studies; D003964:Diaphragm / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D001239:Inhalation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011336:Probability; D012016:Reference Values; D015203:Reproducibility of Results; D015656:Respiratory Mechanics / Q000502:physiology; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler / Q000379:methods; D055815:Young Adult