Department of Animal Medicine, Production and Health, Clinical Section, Radiology Unit, University of Padua, Viale dell'Università 16, AGRIPOLIS, Legnaro 35020, Padua, Italy.
Department of Animal Medicine, Production and Health, Clinical Section, Radiology Unit, University of Padua, Viale dell'Università 16, AGRIPOLIS, Legnaro 35020, Padua, Italy.
Theriogenology. 2017 Jul 1;96:158-163. doi: 10.1016/j.theriogenology.2017.03.011. Epub 2017 Mar 18.
We investigated the quantitative analysis of sonographic images to predict fetal lung maturity of the canine foetus in normal pregnancy. Twelve bitches were recruited in the present study. Serial ultrasonographic exams were performed at three pre-determined time periods corresponding to the pseudoglandular (40-48 days of pregnancy), canalicular (49-56 days of pregnancy) and saccular phase (57-63 days of pregnancy) of lung development. Mean grey level (MGL) and the standard deviation of the histogram (SDH) of fetal lung and liver sonographic images were measured with dedicated software. The lung-to-liver ratio (LLR) for both parameters was also calculated. Measurements were taken on the two caudal-most foetuses and then averaged. SDH did not show any statistically significant difference between the three time periods in the lungs or in the liver. MGL measured in the lungs significantly increased in the first period and reached a plateau during the last two periods. Liver echogenicity was constant during the first two periods and significantly increased during the last week of gestation. The LLR of MGL significantly decreased during the last week of pregnancy. The LLR was a very good test to detect fetal lung maturity (area under the receiver operator curve (AUROC) = 0.875); using a cut-off value of LLR < 1.541, sensitivity was 83.33% and specificity was 83.33%, positive likelihood ratio = 5. LLR of MGL is an accurate test to estimate lung development in normal canine pregnancies.
我们研究了超声图像的定量分析，以预测正常妊娠犬胎儿的肺成熟度。本研究纳入了 12 只母犬。在三个预定的时间点进行了系列超声检查，分别对应于肺发育的假腺泡期（妊娠 40-48 天）、小管期（妊娠 49-56 天）和囊泡期（妊娠 57-63 天）。使用专用软件测量胎儿肺和肝超声图像的平均灰度（MGL）和直方图标准差（SDH）。还计算了这两个参数的肺肝比（LLR）。在两个最尾端的胎儿上进行测量，然后取平均值。SDH 在肺部或肝脏的三个时期之间均无统计学差异。MGL 在第一个时期显著增加，在最后两个时期达到平台期。肝脏回声强度在前两个时期保持不变，在妊娠的最后一周显著增加。MGL 的 LLR 在妊娠的最后一周显著下降。LLR 是检测胎儿肺成熟度的一项非常好的测试（受试者工作特征曲线下面积（AUROC）= 0.875）；使用 LLR <1.541 的截断值，灵敏度为 83.33%，特异性为 83.33%，阳性似然比为 5。MGL 的 LLR 是评估正常犬妊娠中肺发育的准确测试。
