Subserosal

Subserosal refers to a location beneath or on the outer serous covering (serosa) of an organ. In anatomy, the serosa is the outermost layer of many intraperitoneal organs; the subserosa is a connective tissue layer beneath it that may contain small vessels and adipose tissue. The term is most commonly used in gynecology to describe a type of uterine fibroid that grows on the outer surface of the uterus, projecting into the peritoneal cavity.

Subserosal fibroids (leiomyomas) may be pedunculated, connected to the myometrium by a stalk, and can enlarge while distorting the uterus or causing bulk-related symptoms or pressure on adjacent structures. They are distinguished from intramural fibroids (within the uterine wall) and submucosal fibroids (protruding into the endometrial cavity). In imaging and clinical evaluation, subserosal fibroids can be mistaken for ovarian masses, particularly when highly pedunculated, underscoring the need to assess the organ of origin carefully.

Outside gynecology, the term can describe the subserosal layer of non-gynecologic organs, such as sections of the gastrointestinal tract, where the subserosa lies between the muscularis propria and the serosa. This layer contains connective tissue, blood vessels, lymphatics, and nerves, and may be involved in procedures or disease processes affecting the serosa or surrounding tissues.

Management of subserosal fibroids is guided by symptoms, size, patient goals, and overall health, with options ranging from watchful waiting to medical therapy or surgical removal, including myomectomy or hysterectomy for fibroids. In other contexts, treatment decisions depend on the specific organ involved and the condition affecting the subserosal layer.