Laser Speckle Flowgraphy Can Support Intraoperative Assessment of Deep Inferior Epigastric Perforator Flap Blood Flow With Indocyanine Green.

Background: Accurately evaluating cutaneous blood flow during the elevation of a deep inferior epigastric perforator (DIEP) flap may reduce postoperative complications in breast reconstruction surgery. This study examined whether laser speckle flowgraphy (LSFG) could be used to help objectively identify the safe areas of DIEP flaps.

Methods: Forty-eight patients who underwent unilateral breast reconstruction with a DIEP flap at Shinshu University Hospital between 2020 and 2024 were prospectively studied. During flap elevation, skin blood flow throughout the flap was measured using LSFG and compared with results obtained by indocyanine green (ICG) angiography. The cohort was also divided according to the number and location of perforators, and an intergroup comparison was performed according to LSFG readings.

Results: In all subjects, relative LSFG blood flow in zones 2 (89.1%) and 3 (87.9%) was comparable, whereas blood flow in zone 4 (72.8%) was significantly lower than in those areas (both P < 0.001). In the lateral row group, blood flow in zone 2 tended to be lower and in zone 3 tended to be higher than in the medial row group (zone 2: 82.6% versus 89.5%, zone 3: 93.6% versus 86.8%). LSFG values did not differ significantly in relation to perforator number. LSFG-determined blood flow in the stained side of the ICG-determined staining border was significantly higher than in the nonstained side (80.6% versus 71.4%, P < 0.001).

Conclusions: LSFG enables objective, noninvasive evaluation of safety margins in DIEP flaps that may support ICG angiography. Safe zones may vary depending on the location of the selected perforator.