PURPOSE: To compare postnatal survival to hospital discharge of fetuses with severe isolated left-sided congenital diaphragmatic hernia, who underwent tracheal occlusion, with that of nonrandomized contemporaneous controls. METHODS: Experimental nonrandomized controlled study, performed from April 2007 to September 2011. Fetuses with severe isolated left-sided congenital diaphragmatic hernia with liver herniation into the chest and lung area-to-head circumference ratio <1.0, who underwent tracheal occlusion (study group) or expectant management (non-randomized contemporaneous controls), were compared in terms of lung area-to-head circumference ratio and observed/expected lung area-to-head circumference ratio (observed/expected lung area-to-head circumference ratio) at the time of diagnosis, gestational age at birth, and survival to hospital discharge. Modifications in lung area-to-head circumference ratio and o/e lung area-to-head circumference ratio after tracheal occlusion were also analyzed. Fisher's exact test, Mann-Whitney's or Wilcoxon's tests were used for the comparisons. RESULTS: There were no significant differences between the Study Group (TO=28) and Controls (n=13) in terms of the lung area-to-head circumference ratio (p=0.709) and the observed/expected lung area-to-head circumference ratio (p=0.5) at the time of diagnosis and gestational age at birth (p=0.146). The survival to hospital discharge was higher (p=0.012) in the tracheal occlusion group (10/28=35.7%) than in controls (0/13=0.0%). There was a significant increase in lung area-to-head circumference ratio (p<0.001) and observed/expected lung area-to-head circumference ratio (p<0.001) between the diagnosis of the congenital diaphragmatic hernia [lung area-to-head circumference ratio: 0.80 (0.40-0.94); observed/expected lung area-to-head circumference ratio: 27.0 (15.3-45.0)], and the day before retrieval of the balloon [lung area-to-head circumference ratio: 1.2 (0.50-1.80); observed/expected lung area-to-head circumference ratio: 40.0 (17.5-60.0)]. CONCLUSIONS: There was a significant improvement in the survival rate to hospital discharge of fetuses with severe isolated left-sided congenital diaphragmatic hernia, who underwent tracheal occlusion in comparison to nonrandomized contemporaneous controls.3312381387Langham, M.R., Kays, D.W., Ledbetter, D.J., Frentzen, B., Sanford, L.L., Richards, D.S., Congenital diaphragmatic hernia. Epidemiology and outcome (1996) Clin Perinatol, 23 (4), pp. 671-688Lally, K.P., Congenital diaphragmatic hernia (2002) Curr Opin Pediatr, 14 (4), pp. 486-490Moore, A., Umstad, M.P., Stewart, M., Stokes, K.B., Prognosis of congenital diaphragmatic hernia (1998) Aust N Z J Obstet Gynaecol, 38 (1), pp. 16-21Bétrémieux, P., Lionnais, S., Beuchée, A., Pladys, P., le Bouar, G., Pasquier, L., Perinatal management and outcome of prenatally diagnosed congenital diaphragmatic hernia: A 1995-2000 series in Rennes University Hospital (2002) Prenat Diagn, 22 (11), pp. 988-994Jani, J., Gratacós, E., Greenough, A., Pieró, J.L., Benachi, A., Harrison, M., Percutaneous Fetal Endoscopic Tracheal Occlusion (FETO) for severe left-sided congenital diaphragmatic hernia (2005) Clin Obstet Gynecol, 48 (4), pp. 910-922Harrison, M.R., Mychaliska, G.B., Albanese, C.T., Jennings, R.W., Farrell, J.A., Hawgood, S., Correction of congenital diaphragmatic hernia in utero IX: Fetuses with poor prognosis (liver herniation and low lung-to-head ratio) can be saved by fetoscopic temporary tracheal occlusion (1998) J Pediatr Surg, 33 (7), pp. 1017-1022Flake, A.W., Crombleholme, T.M., Johnson, M.P., Howell, L.J., Adzick, N.S., Treatment of severe congenital diaphragmatic hernia by fetal tracheal occlusion: Clinical experience with ffteen cases (2000) Am J Obstet Gynecol, 183 (5), pp. 1059-1066Metkus, A.P., Filly, R.A., Stringer, M.D., Harrison, M.R., Adzick, N.S., Sonographic predictors of survival in fetal diaphragmatic hernia (1996) J Pediatr Surg, 31 (1), pp. 148-151Lipshutz, G.S., Albanese, C.T., Feldstein, V.A., Jennings, R.W., Housley, H.T., Beech, R., Prospective analysis of lung-to-head ratio predicts survival for patients with prenatally diagnosed congenital diaphragmatic hernia (1997) J Pediatr Surg, 32 (11), pp. 1634-1636Sbragia, L., Paek, B.W., Filly, R.A., Harrison, M.R., Farrell, J.A., Farmer, D.L., Congenital diaphragmatic hernia without herniation of the liver: Does the lung-to-head ratio predict survival? (2000) J Ultrasound Med, 19 (12), pp. 845-848Laudy, J.A., van Gucht, M., van Dooren, M.F., Wladimiroff, J.W., Tibboel, D., Congenital diaphragmatic hernia: An evaluation of the prognostic value of the lung-to-head ratio and other prenatal parameters (2003) Prenat Diagn, 23 (8), pp. 634-639Heling, K.S., Wauer, R.R., Hammer, H., Bollmann, R., Chaoui, R., Reliability of the lung-to-head ratio in predicting outcome and neonatal ventilation parameters in fetuses with congenital diaphragmatic hernia (2005) Ultrasound Obstet Gynecol, 25 (2), pp. 112-118Jani, J., Keller, R.L., Benachi, A., Nicolaides, K.H., Favre, R., Gratacos, E., Prenatal prediction of survival in isolated left-sided diaphragmatic hernia (2006) Ultrasound Obstet Gynecol, 27 (1), pp. 18-22Jani, J., Nicolaides, K.H., Keller, R.L., Benachi, A., Peralta, C.F., Favre, R., Observed to expected lung area to head circumference ratio in the prediction of survival in fetuses with isolated diaphragmatic hernia (2007) Ultrasound Obstet Gynecol, 30 (1), pp. 67-71Jani, J.C., Cordier, A.G., Martinovic, J., Peralta, C.F., Senat, M.V., Segers, V., Antenatal ultrasound prediction of pulmonary hypoplasia in congenital diaphragmatic hernia: Correlation with pathology (2011) Ultrasound Obstet Gynecol, 38 (3), pp. 344-349Deprest, J., Gratacos, E., Nikolaides, K.H., FETO Task Group. Fetoscopic tracheal occlusion (FETO) for severe congenital diaphragmatic hernia: Evolution of a technique and preliminary results (2004) Ultrasound Obstet Gynecol, 24 (2), pp. 121-126Jani, J.C., Nicolaides, K.H., Gratacós, E., Valencia, C.M., Doné, E., Martinez, J.M., Severe diaphragmatic hernia treated by fetal endoscopic tracheal occlusion (2009) Ultrasound Obstet Gynecol, 34 (3), pp. 304-310Peralta, C.F.A., Sbragia, L., Corrêa-Silva, E.P.B., Young Oh, G.H., Braga, A.F.A., Gomes, D.A.C., Complicações maternas decorrentes das cirurgias endoscópicas em Medicina fetal (2010) Rev Bras Ginecol Obstet, 32 (6), pp. 260-266Peralta, C.F., Sbragia, L., Bennini, J.R., Braga, A.F.A., Rousselet, M.S., Rosa, I.R.M., Fetoscopic endotracheal occlusion for severe isolated diaphragmatic hernia: Initial experience from a single clinic in Brazil (2011) Fetal Diagn Ther, 29 (1), pp. 71-77Peralta, C.F., Cavoretto, P., Csapo, B., Vandecruys, H., Nicolaides, K.H., Assessment of lung area in normal fetuses at 12-32 weeks (2005) Ultrasound Obstet Gynecol, 26 (7), pp. 718-724Flageole, H., Evrard, V., Vandenberghe, K., Lerut, T.E., Deprest, J.A., Tracheoscopic endotracheal occlusion in the ovine model: Technique and pulmonary effects (1997) J Pediatr Surg, 32 (9), pp. 1328-1331Deprest, J.A., Evrard, V.A., van Ballaer, P.P., Verbeken, E., Vandenberghe, K., Lerut, T.E., Tracheoscopic endoluminal plugging using an infatable device in the fetal lamb model (1998) Eur J Obstet Gynecol Reprod Biol, 81 (2), pp. 165-169