Reliability of the lung to thorax transverse area ratio as a predictive parameter in fetuses with congenital diaphragmatic hernia

Prognostic factors of gastroesophageal reflux disease in congenital diaphragmatic hernia: a multicenter study

“…Information about the severity of CDH including findings of liver herniation (prenatally detected herniation, occupying more than 1/3 of the thoracic space), position of the stomach, observed-to-expected lung area-to-head circumference ratio (o/e LHR), lung-to-thorax transverse area ratio (L/T ratio) [16], defect size of the diaphragm categorized into 4 groups (defect of \25 %, C25 and \75 %, C75 and \100 %, and agenesis), and the use of inhaled nitric oxide (iNO), extracorporeal membrane oxygenation (ECMO) or patch for closure were also reviewed. Home treatment including ventilatory support, oxygen administration, tracheotomy, tube feeding, or vasodilator administration at the time of hospital discharge, and evaluation of developmental delay at 1.5, 3 and 6 years of age were also reviewed.…”

Prenatal risk stratification for isolated congenital diaphragmatic hernia: results of a Japanese multicenter study

“…Briefly, the L/T ratio was defined as the area of the contralateral lung, which was determined by tracing around the contralateral lung, divided by the area of the thorax surrounded by the inner border of the bilateral ribs, the sternum, and the vertebra [15]. The cutoff value of the L/T ratio was set at 0.08 based on our previous studies [15,16,26]. Polyhydramnios, liver-up, and contralateral stomach herniation were categorized as positive if 1 of the 3 determinations was positive.…”

“…In contrast, the contralateral lung-to-thorax transverse area ratio (L/T ratio) appears to be a reliable predictive parameter in fetal CDH, as it was originally reported to be constant throughout the gestational period in normal fetuses [12], and is reportedly not strongly influenced by gestational age even in fetuses with CDH [15,16]. Although combining several reliable prognostic parameters including the L/T ratio may contribute to the establishment of a prenatal risk stratification system for fetal CDH, such approaches have not been successful to date.…”

“…Stomach position was also studied as a prognostic indicator along with liver herniation [8][9][10]. Moreover, estimation of fetal lung size or evaluation of fetal lung characteristics has reportedly been used for severity prediction [11][12][13][14][15][16][17][18]. Among these fetal lung assessments, the lung area-to-head circumference ratio (LHR) is the most commonly used as a prenatal prognostic factor [8,11,18].…”

“…Among these fetal lung assessments, the lung area-to-head circumference ratio (LHR) is the most commonly used as a prenatal prognostic factor [8,11,18]. However, LHR is no longer considered to be independently predictive of survival by several investigators [2,[19][20][21] because it has been shown to increase according to gestational age [15,16,22,23]. The observed to expected LHR has been proposed to provide a constant value throughout the gestational period [22], but in that study, this value was standardized by the normal lung size value of each population corresponding to gestational age without taking individual fetal growth into consideration.…”