title: Ultrasound-guided radiofrequency-driven umbilical cord occlusion: an in-vitro study.
abstract: OBJECTIVE
  To assess the ability and safety of radiofrequency (RF) to induce cord thermal lesions using in-vitro perfused umbilical cords.
  
  
  METHODS
  Nineteen human term umbilical cords were cannulated at both ends and perfused continuously with saline serum in a saline serum bath (37 degrees C). The RF electrode was then inserted into the cord close to the umbilical vein. Different RF power and temperature controls were applied to determine the optimal RF procedure in terms of cord tissue injury and safety in nine experiments. The safety of RF procedures was investigated in ten cords by measuring temperature changes at different sites close to the RF electrode insertion and the impact of RF on cord narrowing was evaluated by continuous monitoring of intraluminal pressure. Subsequent histopathological analysis was carried out in all cases.
  
  
  RESULTS
  The optimal RF procedure reached a temperature of 100 degrees C in 10 min. RF produced a significant increase in intraluminal pressure (from 54.2 +/- 16.4 mmHg at baseline to 118.3 +/- 42.7 mmHg after 10 min, P < 0.05). There was no significant increase in temperature next to the site of insertion during the RF procedure. Histopathological analysis confirmed a > 30% decrease in cord and vein diameter. Cord tissue lesions were characterized by damage in the vessel walls and in the surrounding Wharton's jelly.
  
  
  CONCLUSIONS
  Our results suggest that RF might be a feasible and safe technique to induce occlusion of umbilical vessels. Further in-vivo experiments are needed to assess its ability to induce a complete occlusion of the umbilical cord.
authors.affiliation: Laboratory of Surgery School, Faculty of Medicine, Comprehensive Cancer Center, Nancy, France. olivier.morel17@wanadoo.fr
authors.forename: O
authors.initials: O
authors.lastname: Morel
authors.forename: N
authors.initials: N
authors.lastname: Tran
authors.forename: F
authors.initials: F
authors.lastname: Marchal
authors.forename: V
authors.initials: V
authors.lastname: Hennequin
authors.forename: B
authors.initials: B
authors.lastname: Foliguet
authors.forename: J P
authors.initials: JP
authors.lastname: Villemot
authors.forename: O
authors.initials: O
authors.lastname: Thiebaugeorges
mesh_terms: D017115:Catheter Ablation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D004621:Embolization, Therapeutic / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006358:Hot Temperature; D006801:Humans; D066298:In Vitro Techniques; D011247:Pregnancy; D018607:Pregnancy Reduction, Multifetal / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D018084:Ultrasonography, Interventional / Q000379:methods; D014470:Umbilical Cord / Q000502:physiology / Q000601:surgery*