Quantitative and qualitative evaluations of fetal lung with MR imaging.
OBJECTIVE
To measure both volume and signal intensity of the fetal lung at magnetic resonance (MR) imaging and to evaluate the clinical use of this method to predict fetal pulmonary hypoplasia.


METHODS
A total of 87 fetuses evaluated with MR imaging at 24-39 weeks of gestation were classified into a control group with good respiratory outcome (group A, n = 58) or a poor outcome group with severe respiratory disturbance after birth (group B, n = 29). Planimetric measurement of total lung volume and calculation of the ratio of lung signal intensity to spinal fluid signal intensity (L/SF) were performed on MR images by using region-of-interest analysis. Regression analysis, analysis of covariance, analysis of variance, and receiver operating characteristic (ROC) analysis were performed.


RESULTS
The best fit for group A lung volume was represented by the regression line V = (2.41 x G) - 37.6 (r = 0.537, P <.001), in which V is lung volume and G is gestational weeks; that for group B, by V = (0.97 x G) - 14.0 (r = 0.378, P <.05). Results of analysis of covariance with gestational weeks used as a covariate showed a significant difference in lung volume between the two groups (P <.001). Mean +/- SEM for L/SF ratio was 0.817 +/- 0.013 and 0.598 +/- 0.019 in groups A and B, respectively (P <.001). For prediction of postnatal respiratory outcome, the area under the ROC curve for lung volume and L/SF ratio combined was 0.990, significantly higher than that for lung volume alone (P <.05).


CONCLUSIONS
Simultaneous measurement of fetal lung volume and signal intensity on MR images is a promising method for predicting fetal pulmonary hypoplasia.
Osada
Hisao
H
Department of Obstetrics and Gynecology, Chiba University Hospital, Chiba University School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677 Japan. hosada@mue.biglobe.ne.jp
Kaku
Kenshi
K
Masuda
Kentaro
K
Iitsuka
Yoshinori
Y
Seki
Katsuyoshi
K
Sekiya
Souei
S
D005325:Fetal Organ Maturity; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000196:embryology* / Q000473:pathology; D008176:Lung Volume Measurements; D008279:Magnetic Resonance Imaging; D011296:Prenatal Diagnosis; D012372:ROC Curve; D012120:Respiration Disorders / Q000175:diagnosis / Q000628:therapy; D012121:Respiration, Artificial; D012680:Sensitivity and Specificity