Uterine fibroid pseudocapsule studied by transmission electron microscopy.

Objective: The fibroid pseudocapsule is a structure which surrounds the uterine fibroid, separates it from the uterine tissue and contains a vascular network rich in neurotransmitters like a neurovascular bundle. The authors examined the composition of the fibroid pseudocapsule using electron microscopy.

Study Design: Twenty non-pregnant patients were submitted to laparoscopic myomectomy by the intracapsular method and samples of the removed pseudocapsules were analyzed using transmission electron microscopy.

Results: At the ultrastructural level the pseudocapsule cells have the features of smooth muscle cells similar to the myometrium. So, the pseudocapsules are part of the myometrium which compresses the leiomyoma.

Conclusion: This ultrastructural feature suggests that when removing fibroids their pseudocapsules should be preserved. This study confirms preliminary evidence that pseudocapsules contain neuropeptides together with their related fibers, as a neurovascular bundle. The surgeon's behavior should be directed to carefully control and spare this muscular surrounding tissue during fibroid excision, in order to preserve the myometrium as much as possible.