title: Flexible CO2 laser and submucosal gel injection for safe endoluminal resection in the intestines.
abstract: BACKGROUND
  The CO(2) laser's unique wavelength of 10.6 μm has the advantage of being readily absorbed by water but historically limited it to line-of-sight procedures. Through recent technological advances, a flexible CO(2) laser fiber has been developed and holds promise for endoluminal surgery. We examined whether this laser, along with injection of a water-based gel in the submucosal space, will allow safe dissection of the intestines and enhance the potential of this tool for minimally invasive surgery.
  
  
  METHODS
  Using an ex vivo model with porcine intestines, spot ablation was performed with the flexible CO(2) laser at different power settings until transmural perforation. Additionally, excisions of mucosal patches were performed by submucosal dissection with and without submucosal injection of a water-based gel.
  
  
  RESULTS
  With spot ablation at 5 W, none of the specimens was perforated by 5 min, which was the maximum recorded time. The time to perforation was significantly shorter with increased laser power, and gel pretreatment protected the intestines against spot ablation, increasing the time to perforation from 6 to 37 s at 10 W and from 1 to 7 s at 15 W. During excision of mucosal patches, 56 and 83% of untreated intestines perforated at 5 and 10 W, respectively. Gel pretreatment prior to excision protected all intestines against perforation. These specimens were verified to be intact by inflation with air to over 100 mmHg. Furthermore, excision of the mucosal patch was complete in gel-pretreated specimens, whereas 22% of untreated specimens had residual islands of mucosa after excision.
  
  
  CONCLUSIONS
  The flexible CO(2) laser holds promise as a precise dissection and cutting tool for endoluminal surgery of the intestines. Pretreatment with a submucosal injection of a water-based gel protects the intestines from perforation during ablation and mucosal dissection.
authors: Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
authors: Joyce T
authors: JT
authors: Au
authors: Arjun
authors: A
authors: Mittra
authors: Joyce
authors: J
authors: Wong
authors: Susanne
authors: S
authors: Carpenter
authors: Joshua
authors: J
authors: Carson
authors: Dana
authors: D
authors: Haddad
authors: Sebastien
authors: S
authors: Monette
authors: Paula
authors: P
authors: Ezell
authors: Snehal
authors: S
authors: Patel
authors: Yuman
authors: Y
authors: Fong
mesh_terms: D000818:Animals; D004210:Dissection / Q000379:methods; D004867:Equipment Design; D005782:Gels / Q000008:administration & dosage*; D007267:Injections; D007413:Intestinal Mucosa / Q000601:surgery*; D007416:Intestinal Perforation / Q000209:etiology / Q000517:prevention & control; D053685:Laser Therapy / Q000295:instrumentation*; D054020:Lasers, Gas / Q000627:therapeutic use*; D013552:Swine; D014867:Water / Q000008:administration & dosage
chemical_list: D005782:Gels; D014867:Water