Defining Internal Tissue Closure: High-Resolution Ultrasound Evaluation of Interi-A Novel Internal Tissue Closure System.

Background: Seroma remains a leading postsurgical complication in plastic surgery. Conventional drains are ineffective in clearing blood and fluid and closing down surgical spaces. The Interi (Internal Closure System, IC Surgical, Grand Rapids, MI) is comprised of a novel branching internal manifold attached to a self-contained portable pump with a higher, consistent, continuous negative pressure, may reduce this long-standing issue. In addition, high-resolution ultrasound (HRUS) has emerged as an ideal tool to visualize structures, fluid collections, and seromas internally. Objectives: This study evaluates Interi in full abdominoplasty patients utilizing HRUS to evaluate Interi's ability to evacuate blood and fluid, hold internal tissues together and document, for the first time, what internal tissue healing actually looks like radiographically. Methods: An IRB approved, Contract Research Organization reviewed retrospective study evaluated consecutive patients undergoing full abdominoplasty utilizing Interi from July 2020 through March 2021 by three plastic surgeons. HRUS visualized and confirmed the presence or absence of fluid collections and healing tissue planes during the postoperative process. Study data and all adverse events were recorded, with HRUS images reviewed by investigators and confirmed by an independent radiologist. Results: Seventy-one Interi patients were enrolled. Mean age was 43 (range: 21-74) and BMI was 28. Seroma was confirmed clinically and through HRUS in 3/71 patients, and was associated with either clot (2) or failure to activate system (1). Interi's ability to eliminate fluid and approximate/hold surgical tissue planes together was confirmed with HRUS. No other major complications, including abscess, hematomas, or flap necrosis were observed. Conclusions: This novel Internal Tissue Closure System effectively evacuated blood and fluid, approximated and maintained closure of internal tissue planes in abdominoplasty patients, allowing for primary tissue healing and internal wound closure to occur. Healing tissue planes and any fluid present are easily identified on HRUS visualizing actual internal tissue healing with a simple, widely available radiographic scan. Level of Evidence 3: