Instrumental requirements for minimal invasive fetal surgery P Klaritsch, a,b K Albert, b T Van Mieghem, b L Gucciardo, b E Done’, b B Bynens, b J Deprest a,b a Centre for Surgical Technologies, Faculty of Medicine, Katholieke Universiteit (KU) Leuven, Leuven, Belgium b Department of Obstetrics and Gynaecology, Unit for Fetal Diagnosis and Therapy, University Hospital Gasthuisberg, KU Leuven, Leuven, Belgium Correspondence: Dr J Deprest, Department of Obstetrics and Gynaecology, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. Email jan.deprest@uzleuven.be Accepted 25 September 2008. Minimal invasive intrauterine interventions have gained their place in fetal medicine. Interventions on the placenta, umbilical cord, fetal membranes or on the fetus require special endoscopes with their respective sheaths, cannulas and additional instruments. Instruments for fetal therapy are purpose designed for the procedure of interest and most gynaecologists are therefore not familiar with them. We review the currently available instrumentation used during operations for complicated monochorionic multiple pregnancies, congenital diaphragmatic hernia, amniotic band syndrome, urinary tract obstruction and hydrothorax. Keywords Congenital diaphragmatic hernia (CDH), fetal therapy, fetocide, fetoscopy, twin-to-twin transfusion syndrome (TTTS). Please cite this paper as: Klaritsch P, Albert K, Van Mieghem T, Gucciardo L, Done’ E, Bynens B, Deprest J. Instrumental requirements for minimal invasive fetal surgery. BJOG 2009;116:188–197. Introduction At the time of its introduction in the 1970s, fetoscopy was performed for diagnostic as well as therapeutic purposes, for example to obtain fetal blood in the diagnosis of haemoglo- binopathies or to administer blood under direct visual con- trol, to demonstrate pathognomic malformations or to biopsy the fetal skin. The technique did not become widely imple- mented because of its required skills, invasiveness and the lack of appropriate instruments. Later, it became nearly com- pletely abandoned as ultrasound guidance could be used for the same purposes. Video endoscopy boosted operative endoscopy in the 1980s mainly by miniaturisation of telescopes as well as the use of lightweight cameras. 1,2 The creation of ‘Eurofoetus’, a research and development project supported by the European Com- mission, formalised a collaboration between European fetal medicine specialists and a manufacturer of endoscopic instru- ments (Karl Storz, Tuttlingen, Germany). European public funds made it possible to manufacture purpose-designed fetoscopes and instruments that would commercially never have been viable because indications are rare and as the per- ceived medicolegal risks of fetal intervention are high. The first clinical applications were complicated monochorionic twin pregnancies, and a second European research and devel- opment project ‘Eurotwin2twin’ centred on this topic, with as main deliverable a successful clinical randomised trial com- paring fetoscopic laser coagulation and amniodrainage to treat twin-to-twin transfusion syndrome (TTTS). 3 Since then, fetoscopy has gained an established place in fetal medicine and is now used to operate on the placenta, the umbilical cord, the fetal membranes as well as the fetus. 4,5 Although operative fetoscopy shares some hardware generic to endoscopic surgery, it also requires special endo- scopes with a variety of sheaths, cannulas and instruments adapted to the procedure of interest. The purpose of this review was to introduce the obstetricians who are not fami- liar with these and other devices used in fetal therapy, with the exception of those used for fetal cardiovascular inter- ventions, which is practised only in very few centres at this moment. Generic instruments Fetoscopes and embryoscopes The endoscopes that are used today in gynaecology are between 2.0 and 10.0 mm in diameter, 20–40 cm in length, have typi- cally a rod lens system and an eye cap at the end to which the camera connects. The current spectrum of fetoscopes in contrast has a working length of 20–30 cm to enable working anywhere in a (polyhydramniotic) uterine cavity, and diameters of 1.0–3.8 mm. Their length may occasionally 188 ª 2008 The Authors Journal compilation ª RCOG 2008 BJOG An International Journal of Obstetrics and Gynaecology DOI: 10.1111/j.1471-0528.2008.02021.x www.blackwellpublishing.com/bjog Review article