Potential of the SPY intraoperative perfusion assessment system to reduce ischemic complications in immediate postmastectomy breast reconstruction

Abstract

Background: The quality and viability of mastectomy flaps remain a central challenge in reconstructive surgery, particularly for immediate breast reconstruction. Insufficient perfusion in tissue flaps is a leading cause of early complications following reconstructive procedures, and clinical judgment alone is not completely reliable for the assessment of flap viability. Accurate and reliable intraoperative methods for assessment of tissue perfusion are needed to help surgeons identify tissue at risk for ischemia and necrosis, thereby allowing for maneuvers to improve tissue flap viability.

Methods: This study evaluates the use of intraoperative laser angiography using the SPY System (LifeCell Corp., Branchburg, NJ) for the assessment of perfusion in mastectomy flaps for immediate breast reconstruction. The SPY System uses the contrast agent indocyanine green, which has an excellent safety profile and pharmacokinetics that allow for repeat evaluations during the same surgical procedure. In recent work, the SPY System has demonstrated high sensitivity and specificity for detection of tissues at risk for ischemia and necrosis during reconstructive surgery. Using a retrospective, chart-review design, the authors compared consecutive cases of immediate breast reconstruction using a prosthesis, before and after implementation of the SPY System.

Results: Ninety-one subjects were included in the analysis: 52 prior to SPY (Pre-SPY) and 39 after implementation of SPY (Post-SPY). Baseline characteristics were similar between the groups. Both groups had high rates of comorbidities, chemotherapy, and radiation therapy. The rate of postoperative complications was two-fold higher in the Pre-SPY group compared to the Post-SPY group (36.5% vs. 17.9%); this difference was of borderline significance (P = 0.0631). However, mean number of repeat visits to the OR per patient was significantly higher in the Pre-SPY group (1.21 ± 1.47 vs. 0.41 ± 0.71; P = 0.0023). Of the seven patients with complications in the Post-SPY group, five were identified by SPY as having poor flap perfusion; none were identified by clinical judgment alone.

Conclusions: This study suggests that the SPY System can contribute to reduced ischemia-related complications in a population of women undergoing immediate breast reconstruction following mastectomy for breast cancer.

Figure 1

Illustration of the use of the SPY System for evaluation of tissue perfusion in a mastectomy flap. The black-and-white fluorescence image (Panel A) shows large dark area of minimal fluorescence, reflecting poor perfusion, surrounding the incision; the surgeon’s pen can be seen tracing the outline of this region. Panel B is a colorized version of the same image, showing quantification of absolute fluorescence (numbers in boxes); darker colors represent areas of lower fluorescence signal. The incision prior to reconstruction is shown in Panel C; areas of poor perfusion identified by SPY are noted in blue-pen outlines superior and inferior to the incision. In this case, clinical judgment of tissue viability (including appearance of skin and presence of bleeding at tissue edge) was favored over SPY findings, and the regions of poor perfusion noted on SPY were left intact. The post-operative result (Panel D) shows necrosis superior to the incision, corresponding to the region of poor perfusion identified by SPY.

Figure 2

Use of SPY to identify areas of poor perfusion prior to reconstruction. The colorized SPY image of the left breast (Panel A) shows a region of low fluorescence (dark blue), corresponding to the nipple-areola complex (NAC). Numbers reflect quantification of absolute fluorescence values. Based on clinical judgment of tissue viability (including appearance of skin and presence of bleeding at tissue edge), the area identified by SPY was not removed. Following reconstruction (Panel B), the NAC appears dusky inferior to the incision. Ultimately, the NAC region identified by SPY as having poor perfusion developed necrosis (Panel C) and required return to the OR for debridement and removal of the NAC (Panel D).