Mass distorting the myometrium; most common location.

Mass distorting the myometrium; most common location.

• A. Intramural leiomyoma
• B. Subserosal leiomyoma
• C. Submucosal leiomyoma
• D. Leiomyosarcoma

Answer: (A)

The mass that distorts the myometrium most often is an intramural leiomyoma, a fibroid that originates within the muscular wall of the uterus. Because it grows inside the myometrium, it expands and alters the architecture of the uterine wall itself, leading to irregular thickening or distortion of the myometrial contours on imaging. This is the most common location for fibroids to cause wall distortion. Subserosal fibroids push toward the outer surface of the uterus and may deform the serosal contour, but their growth is outward from the wall rather than within it. Submucosal fibroids grow into the uterine cavity and tend to distort or protrude into the endometrial cavity rather than primarily distorting the myometrium. Leiomyosarcoma is a malignant tumor and, while it can involve the myometrium, is not the typical, most common cause of myometrial distortion.

The mass that distorts the myometrium most often is an intramural leiomyoma, a fibroid that originates within the muscular wall of the uterus. Because it grows inside the myometrium, it expands and alters the architecture of the uterine wall itself, leading to irregular thickening or distortion of the myometrial contours on imaging. This is the most common location for fibroids to cause wall distortion.

Subserosal fibroids push toward the outer surface of the uterus and may deform the serosal contour, but their growth is outward from the wall rather than within it. Submucosal fibroids grow into the uterine cavity and tend to distort or protrude into the endometrial cavity rather than primarily distorting the myometrium. Leiomyosarcoma is a malignant tumor and, while it can involve the myometrium, is not the typical, most common cause of myometrial distortion.