Megan Mills MD, Presenter: Nothing to Disclose

Thomas Charles Winter MD, Abstract Co-Author: Speakers Bureau, General Electric Company

Anne M. Kennedy MD, Abstract Co-Author: Nothing to Disclose

To determine if fetal lung to fetal organ magnetic resonance signal intensity ratios can be used to predict fetal lung maturity.

This study was a retrospective review of 395 fetal MRI cases from a single institution for the years 2001-2011. All cases were obtained using a 1.5 T MRI. For each case, the T2 SSFE and T1 GRE sequences were selected for data collection. A single reviewer obtained ten regions of interest from each fetus on the PACS system. The 10 variables selected for analysis were fetal lung, fetal liver, fetal muscle, fetal spleen, and maternal urine. Using the electronic medical record, additional information was obtained in order to create a normative data set. For each case, gestational age, Apgar scores, steroid administration, karyotype, and MR diagnosis was obtained.

327 cases met inclusion criteria with gestational ages ranging from 17-39 weeks. A statistically significant relationship of MR signal intensity ratios and gestational age was demonstrated on the T2 lung to liver, T2 lung to spleen, T2 lung to muscle and T1 lung to liver ratios. T2 lung to liver demonstrated the strongest relationship with gestational age (r=0.452, p <0.001). T1 lung to liver demonstrated an inverse relationship with gestational age (r=-0.168, p<0.018).

Currently the only method of determining fetal lung maturity is by invasive means. While using MR fetal lung signal intensity ratios would be a simple, non-invasive tool, it is not clinically relevant; a statistically significant correlation between signal intensity ratios and gestational age is demonstrated, but the large standard deviations at any gestational age limits clinical utility.

An association exists between fetal lung MR signal intensity ratios and gestational age, but the large standard deviation of the predicted gestational age prohibits determination of lung maturity.

Mills, M, Winter, T, Kennedy, A, Determining Fetal Lung Maturity Using Magnetic Resonance Imaging Signal Intensity Ratios.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12031259.html