title: Laser-assisted indocyanine green angiography: a critical appraisal.
abstract: BACKGROUND
  Laser-assisted indocyanine green angiography (ICG-A) has been promoted to assess perfusion of random skin, pedicled, and free flaps. Few studies address its potential limitations.
  
  
  METHODS
  Thirty-seven patients who underwent reconstructive procedures with ICG-A were studied retrospectively to determine the correlation between clinical findings and ICG-A. Indocyanine green angiography underestimated perfusion when areas of less than or equal to 25% uptake were not debrided and remained perfused. Indocyanine green angiography overestimated perfusion when areas with greater than 25% uptake developed necrosis.
  
  
  RESULTS
  Of 14 random skin flaps, ICG-A underestimated perfusion in 14% and overestimated in 14%. In 16 patients undergoing perforator flap breast reconstruction, ICG-A correlated with computed tomographic angiogram (CTA) in 85%. Indocyanine green angiography underestimated perfusion in 7% and overestimated in 7%. In 8/11 patients undergoing fasciocutaneous flaps, ICG-A aided in donor site selection. In 3/6 ALT flaps, a better unilateral blush was found that correlated with Doppler. In all 3, a dominant perforator was found. In 11 patients, there was a 9% underestimation of flap perfusion. In 3 pedicled flaps, there was a 66% underestimation and 33% overestimation of perfusion.
  
  
  CONCLUSIONS
  Indocyanine green angiography often confirmed our clinical/radiologic findings in abdominal perforator and fasciocutaneous flaps. It tended to underestimate perfusion in pedicle and skin flaps. When clinical examination was obvious, ICG-A rendered clear-cut findings. When clinical examination was equivocal, ICG-A tended to provide ambiguous findings, demonstrating that a distinct cutoff point does not exists for every patient or flap. Indocyanine green angiography is a promising but expensive technology that would benefit from standardization. Further research is needed before ICG-A can become a reliable tool for surgeons.
authors.affiliation: Division of Plastic and Reconstructive Surgery, University of North Carolina, Chapel Hill, NC 27599-7195, USA.
authors.forename: Cindy
authors.initials: C
authors.lastname: Wu
authors.forename: Sendia
authors.initials: S
authors.lastname: Kim
authors.forename: Eric G
authors.initials: EG
authors.lastname: Halvorson
mesh_terms: D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D007208:Indocyanine Green; D007834:Lasers; D008297:Male; D061848:Optical Imaging / Q000379:methods*; D019651:Plastic Surgery Procedures; D012189:Retrospective Studies; D013524:Surgical Flaps / Q000098:blood supply*
chemical_list: D005456:Fluorescent Dyes; D007208:Indocyanine Green