Transvaginal in-bag directional morcellation with endometrial preservation for large uteri: an initial clinical feasibility study.

BACKGROUND: To explore the initial clinical feasibility and preliminary surgical safety of transvaginal four-wall directional in-bag morcellation for extracting exceedingly large uteri during laparoscopic total hysterectomy (TLH), aiming to preserve endometrial integrity as an anatomical barrier. METHODS: This retrospective study included 25 patients with large uteri (12-18 gestational weeks) who underwent TLH. Following uterine detachment, a transvaginal isolation bag was inserted to establish a pneumo-bag. Under direct visualization, an electromechanical morcellator performed directional volume reduction on the four myometrial walls. The endometrial layer was strictly preserved. The intact central "core cavity" and morcellated fragments were then extracted en bloc within the bag. RESULTS: All 25 surgeries succeeded without conversion to laparotomy. Mean uterine volume was 725.6 ± 215.4 cm3; mean in-bag morcellation time was 12.5 ± 4.2 min. Postoperative specimen examinations confirmed macroscopic physical integrity of the endometrial cavity in this preliminary cohort. Methylene blue pressure tests showed 100% bag water-tightness. Macroscopically, zero cases of tissue spillage, vaginal wall injury, or postoperative infection occurred. CONCLUSIONS: Transvaginal directional in-bag morcellation appears to be a technically feasible and initially safe surgical option. By establishing a "dual barrier"-an intact endometrial cavity (anatomical) and a sealed bag (physical)-this novel technique shows potential in providing macroscopic physical containment. However, lacking cytological evaluation, long-term follow-up, and a comparative control group, its potential oncological safety benefits remain strictly theoretical at this preliminary stage.