Journal of Perinatology (2014) 34, 941–944 © 2014 Nature America, Inc. All rights reserved 0743-8346/14 www.nature.com/jp PERINATAL/NEONATAL CASE PRESENTATION Complete chorioamniotic membrane separation with constrictive amniotic band sequence and partial extra-amniotic pregnancy: serial ultrasound documentation and successful fetoscopic intervention B Schlehe1, M Elsässer1, S Bosselmann1, R Axt-Fliedner2, C Sohn1 and T Kohl3 Chorioamniotic membrane separation (CMS) comprises cases of spontaneous and iatrogenic detachment between the amniotic and chorionic membranes, with various fetal outcomes due to possible complications, particularly the formation of constrictive amniotic bands and preterm rupture of membranes. In the absence of mandatory management standards conservative monitoring is the most reported approach. In the case we present here, close sonographic surveillance afforded us the opportunity to observe the process from CMS to amnion rupture with the formation of constrictive amniotic bands and threatened cord impairment via constrictive margins of the amniotic sac. Despite the complicated background of reduced membranous layers in ruptured CMS, we performed a successful fetoscopic intervention with band release at 24 weeks’ gestation and the pregnancy was prolonged to 34 weeks under close monitoring. Journal of Perinatology (2014) 34, 941–944; doi:10.1038/jp.2014.159 INTRODUCTION cord insertion (Figure 1). The patient refused karyotyping for Chorioamniotic membrane separation (CMS) may occur as a rare personal reasons. At 22 weeks, the amnion membrane appeared spontaneous event (1:3400)1,2 with possible association to fetal to be ruptured with the lower fetal limbs protruding into malformations or aneuploidy,3 but more often it appears as an the extra-amniotic cavity (Figure 2). At 23 weeks, gross edema iatrogenic complication from invasive intrauterine procedures of the left arm distal to two circumferential constrictions (Figures such as amniocentesis, fetoscopy and open fetal surgery.2,4,5 In 3a and b) was detected, followed by the right arm a few days later. both spontaneous and postinterventional cases CMS may Fetal movements were not restricted and Doppler ultrasound jeopardize pregnancy as it is a risk factor for premature rupture showed present blood flow in both arms distal to the constriction. of membranes and preterm delivery, presumably due to the Because of threatened amputation and cord complication we chorion’s reduced mechanical resistance.6 Mesodermic fibrous referred the patient to the German Center for Fetal Surgery & strings developed from a denuded chorion may lead to amniotic Minimally Invasive Therapy (DZFT), Giessen University Hospital, band syndrome (ABS) with significant morbidity and mortality.7 Germany, to consider fetoscopic intervention. After counseling the Clinical management guidelines for ABS have been suggested,8,9 risk of premature rupture of membranes and preterm birth we while in isolated CMS close monitoring is the most reported obtained informed consent for fetoscopy. After a course of strategy.10 betamethasone (2 × 12 mg), at 24 weeks, we performed percuta- We present a case of extensive CMS where membrane neous fetoscopy via two trocars (external diameter 5 mm). All separation evolves into ABS with ruptured and collapsed amniotic parts of the amniotic sac encircling the insertion of umbilical cord sac and subsequent constriction of the fetal parts and cord. and constricting the fetal occiput, neck and right upper arm were We successfully performed fetoscopic band release, which, to our released (Figure 3c) using endoscopic micro-scissors. We noted knowledge, may be the first described in the setting of several indentations on the left upper arm but no amniotic bands preoperative collapsed amniotic membranes. or residuals. Operative time was 70 min. The patient stayed hospitalized for routine prophylactic tocolysis (Atosiban for 48 h) and intravenous antibiotics (Gentamicin and Clindamycin), sono- CASE graphic monitoring, fetal non-stress test and close surveillance of A 35-year-old woman, gravida 2, para 0, was referred to our chorioamnionitis or amniotic leakage. At 34 weeks, cesarian clinic at 17 weeks’ gestation for suspected CMS. Sonographically section was performed due to spontaneous labor. On the we found an appropriately growing fetus with a right-sided neonate’s right arm, there was no indentation after fetoscopic clubfoot, posterior placentation, normal amniotic fluid volume and band release. The left arm showed five circumferential imprints complete CMS with the amniotic sac anchored at the placental without band residuals (Figure 3d) but subsequent slight elbow 1Department of Obstetrics and Gynecology, University of Heidelberg, Heidelberg, Germany; 2Department of Obstetrics and Gynecology, University of Giessen, Giessen, Germany and 3German Center for Fetal Surgery & Minimally-Invasive Therapy (DZFT), Giessen University Hospital, Giessen, Germany. Correspondence: Dr B Schlehe, Universitätsfrauenklinik Heidelberg, Im Neuenheimer Feld 440, 69120 Heidelberg, Germany. E-mail: [email protected] Received 10 February 2014; revised 23 June 2014; accepted 7 July 2014 Fetoscopic surgery in chorioamniotic membrane separation B Schlehe et al 942 Figure 1. (a, b) Complete chorioamniotic membrane separation at 17 weeks of gestation with the fetus surrounded by detached amnion (arrow). Figure 2. (a–c) After rupture of amnion the fetus head remained in a sac of amniotic membrane, 22 weeks of gestation. (a) Oblique view of the lower face. (b) Longitudinal view of the neck. (c) Fetoscopic view. flexion and finger extension deficit with intermittent clawhand. offered sufficient support and adherence to maintain pregnancy The right foot was clubbed with no other abnormalities. The into the 34th week without amniotic leakage. premature neonate was hospitalized for 3 weeks with an In CMS, clinical experience is limited to case reports and uneventful course. Following physiotherapeutic exercises at pathogenesis is not completely understood, but early leakage of 9 months the baby showed normal neurologic development, amniotic fluid into the chorionic cavity is the most accepted view.7 apart from a minor and decreasing neurologic deficit of the The detached membranes may float,11 entrap the fetus, or rupture left hand. with fetal parts protruding into the extra-amniotic cavity. Fetal outcome varies from intrauterine fetal demise due to cord complications5,10 to otherwise uneventful pregnancies with DISCUSSION mostly preterm delivery.2,4,5,9,11 Although there is a potentially The severity of CMS we report here contrasts with previously lethal risk of cord strangulation that might be hard to predict by described cases as membranous detachment affected the whole ultrasound,5 previous reports of complete CMS suggest expectant cavity and was complicated by amnion rupture with extraamniotic management.10 Amniocentesis is a feasible option for karyotyping fetal parts and ABS. Despite detached and ruptured amniotic and amnioninfusion;11 a detailed search for malformations is membranes and the additional iatrogenic injury, the chorion obligatory. Journal of Perinatology (2014), 941 – 944 © 2014 Nature America, Inc. Fetoscopic surgery in chorioamniotic membrane separation B Schlehe et al 943 Figure 3. (a–d) Gross edema of the left upper arm at 24 weeks of gestation, distal to the site of amniotic band constriction. (a)Two constrictive imprints (arrows). (b) Gross edema of the lower arm and hand. (c) Fetoscopic view. (d) Neonatal aspect of the affected arm. If amniotic band formation is detected, in well-defined cases9 experience and to appreciate the clinical significance of CMS fetoscopic release is the current preferred option.12 Despite a low and ABS. rate of intraoperative bleeding complications, no maternal post- operative complications have been reported in the literature.9,13 13 Limb function preservation was reported in 50% of cases (7/14), CONFLICT OF INTEREST with the majority of interventions performed by laser dissection The authors declare no conflict of interest. (71%), and less frequently by endoscopic scissors (14%).13 Successful blunt dissection is reported in only one case of non-adhesive amniotic bands.14 Preterm premature rupture of membranes was reported in 57% of cases.13 In one case of REFERENCES fetoscopic band release, intraoperative partial amnion separation 1 Levine D, Callen PW, Pender SG, McArdle CR, Messina L, Shekhar A et al. was described with post-interventional fetal loss, presumably due Chorioamniotic separation after second-trimester genetic amniocentesis: impor- 209 – to postoperative collapsed and dissected amnion around the fetus tance and frequency. Radiology 1998; (1): 175 181. 2 Sydorak RM, Hirose S, Sandberg PL, Filly RA, Harrison MR, Farmer DL et al. and cord.9 In the case we report here neither intra- or Chorioamniotic membrane separation following fetal surgery. J Perinatol 2002; 22: postoperative complications nor premature rupture of mem- 407–410. branes occurred in the 10 weeks following. Fetoscopic findings 3 Ulm B, Ulm MR, Bernaschek G. Unfused amnion and chorion after 14 weeks of were concordant with our ultrasound findings, while others report gestation:associated fetal structural and chromosomal abnormalities. Ultrasound intraoperative detection of further constrictions, particularly at the Obstet Gynecol 1999; 13:392–395. umbilical cord.15 At our fetal surgery center it became policy to 4 Wilson RD, Johnson MP, Crombleholme TM, Flake