Kaixi Tan,1 Jianfei Zhang2 

1Department of Burns and Plastic Surgery, The Affiliated Nanhua Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, People’s Republic of China; 2Department of Burns and Plastic Surgery, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, People’s Republic of China

Correspondence: Jianfei Zhang, Department of Burns and Plastic Surgery, The Second Affiliated Hospital, Hengyang Medical School, University of South China, No. 35 Jiefang Avenue, Zhengxiang District, Hengyang, 421001, People’s Republic of China, Tel +86-15173145710, Email 961653946@qq.com

Background: Staged excision is often needed for large CMN. Accurately determining the first-stage excision volume is critical.
Objective: To introduce and evaluate a geometric-marking quantification method for precise preoperative planning of the first-stage excision volume in staged CMN removal.
Methods: A prospective study was conducted on 21 patients undergoing staged excision of large CMN between January and June 2023. Preoperatively, a novel geometric-marking quantification technique was employed to calculate the maximum feasible first-stage excision volume. Surgical execution, intraoperative conditions, and postoperative recovery were observed. Relevant surgical techniques and postoperative care were examined.
Results: All first-stage excisions resulted in successful tension-free primary closure. No instances of insufficient excision, suture dehiscence, or other immediate complications occurred. Postoperative recovery was favorable across all patients. All patients proceeded to successful second-stage excision for complete nevus removal.
Conclusion: The geometric-marking quantification method provides a reliable, reproducible, and objective approach for planning the first-stage excision in large CMN. It achieved 100% technical success in this cohort, eliminating complications related to inaccurate volume estimation. This standardized protocol warrants clinical adoption to replace subjective estimation methods, significantly enhancing surgical outcomes and reducing complication risks.

Keywords: congenital melanocytic nevi, staged excision, geometric marking, precise measurement, surgical planning