One Size Does Not Fit All: Prediction of Nerve Length in Implant-based Nipple-Areola Complex Neurotization.

Background:  Breast reconstruction with sensory restoration is gaining recognition as an important goal. Successful reinnervation has been shown in autologous reconstruction but not widely studied in implant-based reconstruction (IBR). This article describes our technique for nipple-areola complex (NAC) neurotization to predict maximal nerve length. We also propose a novel equation that can be utilized preoperatively to estimate the total nerve length required for NAC neurotization.

Methods:  This is a retrospective study of patients who underwent nerve reconstruction with IBR between April 2021 and May 2022. An equation based on the arc length of a circle was utilized to predict the total nerve length required. Postoperative assessment of sensation was performed at 3, 6, and 12 months using Semmes-Weinstein monofilament testing in all four breast quadrants and the NAC. Patients completed the Breast-Q Sensation Module preoperatively and at 3, 6, and 12 months.

Results:  NAC neurotization was performed in 58 patients undergoing IBR. The average length of intercostal nerve (ICN) harvested was 5.3 cm for staged reconstructions and 5.6 cm for direct-to-implant reconstruction. The average total nerve length (allograft + mobilized ICN) was 12.3 cm. On average, 6.9 cm of nerve allograft was used. The mean difference between total nerve length and predicted nerve length was 0.47 cm (range -3.5 to 4.6 cm). There was a significant improvement in sensory monofilament values measured in all four breast quadrants and the NAC between 3 to 6 and 6 to 12 months postoperatively.

Conclusion:  A thorough understanding of sensory anatomy and precise surgical techniques are essential to perform NAC neurotization successfully. Our early results suggest the positive impact of breast sensation on patient quality of life.