Laser doppler imaging as additional monitoring after digital replanting: A prospective study

Microsurgery. 2018 Sep;38(6):627-633. doi: 10.1002/micr.30318. Epub 2018 Mar 14.

Abstract

Background: Despite various exisiting monitoring methods, there is still a need for new technologies to improve the quality of post-operative evaluation of digital replantation. The purpose of the study is using a laser Doppler imaging device (Easy-LDI) as an additional tool to assess perfusion. In this method, the changes in the frequency of the laser ligth provide information regarding perfusion of the monitored tissue.

Patients and methods: This study included seven patients (10 fingers; age of patients: 21-57 years) who suffered from a total (n = 6) or subtotal amputation (n = 4) due to accidents. In addition to hourly standard monitoring with clinical evaluation and skin thermometry, revascularized fingers were hourly monitored with Easy LDI for 48 h.

Results: LDI measurement values ranged between 0.8 and 223 (mean 90.62 ± 21.42) arbitrary perfusion units (APU). The mean LDI values before and after revascularization were 7.1 ± 2.85 and 65.30 ± 30.83 APU, respectively. For the successful revascularized fingers (8 of 10 fingers) values from 19 to 223 APU (mean 98.52 ± 15.48) were demonstrated. All of the replants survived, but due to venous occlusion two digits required revision 12 and 35 h after revascularization, respectively. In the two cases, Easy-LDI also showed a constant and slow decline of the perfusion values. Furthermore, Pearson normalized correlation coefficient showed a positive significant correlation between temperatures of the replants and LDI-values (P < .001, r = +0.392) and a negative significant correlation between Δtemperature and LDI-values (P < .001, r = -0.474).

Conclusion: The LDI-device might be a promising additional monitoring technique in detection of perfusion disturbance in monitoring digital replantations.

MeSH terms

  • Adult
  • Amputation, Traumatic / diagnostic imaging
  • Amputation, Traumatic / physiopathology
  • Amputation, Traumatic / surgery*
  • Female
  • Finger Injuries / diagnostic imaging*
  • Finger Injuries / physiopathology
  • Finger Injuries / surgery*
  • Humans
  • Laser-Doppler Flowmetry*
  • Male
  • Microcirculation / physiology
  • Microsurgery*
  • Middle Aged
  • Prospective Studies
  • Replantation*
  • Young Adult

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