Evaluation of inguinal vascular surgical scars treated with closed incisional negative pressure wound therapy using three-dimensional digital imaging-A randomized controlled trial on bilateral incisions

Abstract

Purpose of the investigation: Scar formation is an important, permanent surrogate marker for wound healing. The main aim of this randomized trial was to evaluate the effects of incisional negative pressure wound therapy (iNPWT) on scar formation in uncomplicated wound healing with 3-dimensional (3D) digital imaging.

Basic procedures: Patients undergoing bilateral inguinal incisions after vascular surgery were randomized to receive iNPWT and standard dressing on separate sides. The incisional scars were documented at a median time of 808 days (range 394-1194) after surgery with 3D photography, which were objectively evaluated by two plastic surgeons using the Stony Brook scar evaluation scale (SBSES) and a 10-point graded numeric ranking scale (NRS10). Subjective evaluation was performed with the patient observer scar assessment scale (POSAS). Patients with surgical site infection or other wound complications were excluded to minimize bias. The p-values were calculated using McNemar's and Wilcoxon signed-rank test for paired nominal and paired continuous data, respectively.

Main findings: Among 33 patients, 32 patients had undergone endovascular aortic repair (EVAR) and 31 patients had transverse inguinal incisions. Objective and subjective scar evaluation showed no difference between iNPWT and standard dressing. In objective scorings, 18.8 and 21.9% received the highest possible SBSES total score in the iNPWT and standard dressing groups, while 43.8 and 37.5% received the highest possible NRS10 score, respectively. The inter-rater reliability between the two assessors for SBSES total score and NRS10 showed an intra-class correlation (ICC) of 0.78 and 0.68 for NPWT and 0.70 and 0.77 for traditional dressing, respectively.

Principal conclusion: The present randomized trial showed that iNPWT and standard dressings on closed transverse inguinal incisions after EVAR resulted in equal subtle scar formation. Objective scar evaluation with 3D images showed good inter-rater agreement.