A localization-independent approach for invisible and impalpable ground-glass opacity nodules detection in an in vitro lung specimen: two case reports

A growing number of ground-glass opacity (GGO) nodules are screened out in lungs. Small GGOs are frequently neither visible nor palpable, thus undetectable during operation. Various nodule localization techniques have been developed to facilitate the intraoperative detection of GGO nodules; however, general localization techniques are infeasible or inappropriate in some cases. The detection of small GGO is a great challenge, even within a surgical specimen in the absence of preoperative localization. A localization-independent approach for GGO detection is urgently needed. Herein, we report two cases with invisible and impalpable small GGO which were not appropriate for preoperative localization. The lesions were anatomically resected under the guidance of three-dimensional (3D) reconstruction and got an adequate margin distance. A vessel (artery, vein, or bronchus) which had advanced into or immediately adjacent to the nodule was assigned as a reference vessel. By dissecting and tracing the reference vessel from proximal to distal, the GGO lesions were successfully detected in the surgical specimens, to the eventual obtainment of an accurate pathological diagnosis. Via the two case reports, we introduced an easily handled approach, namely dissecting and tracing a reference vessel, for GGO detection. The novel approach was first described. Combined with precise anatomical segmentectomy guided by 3D reconstruction, it provides an alternative scheme for GGO resection with no need for preoperative localization.