Specialized Infrared Camera-Computer System (SPY) Imaging for Monitoring the Restoration of Nipple Sensation in Patients Undergoing Breast Reduction

Introduction Symptomatic mammary hypertrophy (SMH) refers to excessive breast weight exceeding 3% of total body weight, impacting not only the breast but also the nipples and areola. Breast reduction surgery (BRS) has a complication that adversely affects the nipple-areolar complex (NAC) sensation. The purpose of this study was to estimate the degree to which the specialized infrared camera-computer system (SPY) may predict postoperative sensation of the NAC following BRS. Methods A retrospective, observational study that included 408 SMH patients who underwent BRS was conducted at the Division of Plastics Surgery at the University of Florida College of Medicine - Jacksonville. Breast surgery patients were grouped according to whether SPY was used intraoperatively (SPY group) or not used intraoperatively (NOSPY group) during surgery. A chi-square test was used to evaluate whether a percentage difference existed between the SPY group and the NOSPY group. The main outcomes were unchanged, decreased, or increased NAC sensation. An Eta square was used to measure the effect sizes of profusion variance associated with reported nipple sensation. An area under the curve (AUC) was performed to determine the most favorable cutoff for SPY profusion sensitivity and specificity. A nominal regression model was used to determine the correlation between NAC sensation and SPY usage. A probability value less than 0.05 was considered statistically significant. Results Of the 408 SMH patients included in the study, SPY technology was incorporated for 63 patients (15.4%). The percentage of those who reported decreased nipple sensation with the use of SPY was 29 (47.6%). The percentage of those who reported increased nipple sensation with the use of SPY was 4 (6.4%). The percentage of patients who reported no change in nipple sensitivity with the use of SPY was 29 (46.0%). The chi-square test was statistically significant (χ2 = 302.29, df = 2, p < 0.001). The Eta squared for the right breast SPY profusion percent was 0.74 and for the left breast SPY profusion percent was 0.81. Both percentages represent large effect sizes as the proportion of variance associated with the reported nipple sensation. The AUC for the SPY profusion was 0.471, which was not statistically significant. The most favorable receiver operator characteristic curve SPY profusion sensitivity was 0.651, with a specificity of 0.690 and an associated cutoff of 65.5. The outcome variable, NAC sensation, was determined to be significantly correlated with SPY use predicting decreased and increased NAC sensitivities (OR 3.6; p < 0.001 and OR 6.4; p = 0.007), respectively. Conclusions Although SPY technology has traditionally been utilized to assess tissue perfusion, our study demonstrates its potential as a predictive tool for postoperative NAC sensation.