Photoacoustic Imaging of Midline-Crossing Vessels and Implications for Surgical Strategy in Patients With Midline Abdominal Scars.

[INTRODUCTION] Blood vessels are severed in patients with midline vertical abdominal scars, but detailed reports on the status of vessels penetrating the scar or vertical location from the umbilicus of the midline-crossing vessels in vivo are lacking. We revealed the effects of the scar and anatomical features of midline-crossing vessels using photoacoustic imaging.

[METHODS] Women in the outpatient follow-up period of the gynecology and gastrointestinal surgery department of our institution were included. Ultrasonography and photoacoustic imaging were performed. The region of interest (ROI) was set 3-12 cm below the umbilicus. Patients were categorized into three groups: Group 1, no surgical scars within the ROI; Group 2, surgical scars along the entire length of the ROI; Group 3, a mixture of areas with and without scars. The numbers of midline-crossing arteries (MCA) and veins (MCV) were compared between Groups 1 and 2. The vertical position of the MCA and MCV from the umbilicus was investigated in Group 1.

[RESULTS] MCA and MCV were observed in all patients in Group 1 (n = 14), and the median number of MCA was 2, while the median number of MCV was 5. Three patients in Group 2 (n = 17) had MCV, although none of the patients had MCA. In Group 3 (n = 6), residual MCA was found apart from the scar. In half of Group 1, the MCA was not visualized within 4 cm caudal to the umbilicus, but MCV was visualized in all cases.

[CONCLUSIONS] Although MCA was not depicted within the scar, MCV was visualized penetrating the scar in some patients. The results of Group 1 showed that there are individual differences in the location of the MCA. Detecting residual MCA and MCV in Group 3 implies the ability of photoacoustic tomography to assess a surgical application for a single-pedicle transverse abdominal flap in breast reconstruction.