Detection of free flap pedicle thrombosis by infrared surface temperature imaging

Cherng Kang Perng*, Hsu Ma, Yu Jen Chiu, Pei Hsin Lin, Chi Han Tsai

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

12 Scopus citations


Background: Reliable detection of any circulatory issue threatening flap viability after free flap surgery is essential for prompt flap salvage. Currently, the gold standard of flap monitoring is clinical monitoring. However, this method presents logistical challenges to insufficient trained personnel. Auxiliary methods are becoming increasingly vital. Materials and methods: Twelve swine pedicle myocutaneous flaps were harvested and monitored using infrared cameras to investigate the developed monitoring parameters and vascular thrombosis in the free flap model. Results: The mean flap surface temperature after vein or artery occlusion decreased significantly, but the differences were relatively small. As a result, the difference between recorded (flap surface temperature [T s ]) and predicted (estimated surface temperature [T es ]) flap surface temperature (ΔT = T s − T es ) was used as the parameter for pedicle thrombosis. A ΔT of <0.86°C was used as a vascular occlusion criterion; the sensitivity and specificity of this parameter were 90% and 81%, respectively. The standard deviation of the surface temperature (SD T ) was another indicator of vascular occlusion; the estimated sensitivity and specificity for vessel occlusion of SD T < 0.48°C were 84% and 73%, respectively. Conclusions: Infrared thermal imaging has the advantages of being noninvasive, contact-free, continuous, and able to detect the whole flap surface area. Two indicators, ΔT and SD T , can be used with high sensitivity and specificity for early prediction of flap pedicle thrombosis. Further human studies are necessary to validate clinical application of infrared thermal imaging.

Original languageEnglish
Pages (from-to)169-176
Number of pages8
JournalJournal of Surgical Research
StatePublished - Sep 2018


  • Free flap
  • Infrared thermal imaging
  • Pedicle thrombosis


Dive into the research topics of 'Detection of free flap pedicle thrombosis by infrared surface temperature imaging'. Together they form a unique fingerprint.

Cite this