Focal adenomyomas also occur. These are difficult to distinguish from fibroids. Fibroids tend to be well arcumscni bed. In contrast, focal adenomyomas are ill defined and may have lacunae The preop rative distinction between fibroids and adenomyosis is important in women who are being treated for inferti lityor abnormal bleed ing since myomas can be removed; however, a denomyos is typically requires a hysterectomy. Magneticresonance is helpful in this dist inction (20) obstruction tients with hydrocolpos(fluid in the vagina) and hydrometrocolpos(fluid in the vagina and uterus)usually are studied soon after birth or at puberty when secretions ca obstruction because of an intact hymen or vaginalatresia Hematometra is seen in patients with cervical cancer or cervical stenosis(Fig. 28-17) Figure-28-17 Hematometra. Sagittal view of the uterus in a 63-year-old asymptomatic woman placed on cydic hormonal replacement therapy demonstrates a large endometrial fluid col lection with a thin suround ing ndometrium. she subsequently underwentsurgical dilation for cervical stenosis (Levine D. The postmenopausal pelvis. In: Nyberg DA, ed Transvaginal ultrasound. St Louis, MO, Mosby Year Book, 1992:228) Endometrial Cancer llargement of the uterus is a late finding in endometrial cancer. This disease is discussed in more detailin Chapter 29 Bright Reflectors In The Uterus Causes of brightechoes in the uterusand endometrium are listed in(Table 28-12 Uterine calcifications The most common cause of dense echoes in the ute rs ations resulting from fibroids. These appears dumps of cal dification( Fig. 28-18A)or as rim caldficationa Figure-28-18a. Uterine calcifications. Transvaginal transverse view of the uterus in a postmenopausal woman with abnormal bleeding demonstrates a well-defined echogenic focus with shadowing secondary to a calcified fibroid. Adjacent to this area is a fluid collection in a region of thickened endometrium(arrows). This was Aless common cause of calcificaton within the uterus is that of the arcuate artery. Arcuate artery calcifications are seen around the periphery of the uterus, usually in older w with severe medical problems suchas diabetes, chronicrenal failure, or hypertension. (21) actate calcifications occasiona lly are seenat the endometrial myometrial interface(see Fig. 28-18B) These are probably secondary to a prior infection or procedureFocal adenomyomas also occur. These are difficult to distinguish from fibroids. Fibroids tend to be well circumscribed. In contrast, focal adenomyomas are ill defined and may have lacunae. The preoperative distinction between fibroids and adenomyosis is important in women who are being treated for infertility or abnormal bleed ing since myomas can be removed; however, adenomyosis typically requires a hysterectomy. Magnetic resonance is helpful in this distinction. (20) Obstruction Patients with hydrocolpos (fluid in the vagina) and hydrometrocolpos (fluid in the vagina and uterus) usually are studied soon after birth or at puberty when secretions cause obstruction because of an intact hymen or vaginal atresia. Hematometra is seen in patients with cervical cancer or cervical s tenosis (Fig. 28-17) . Figure - 28-17. Hematometra. Sagittal view of the uterus in a 63-year-old asymptomatic woman placed on cyclic hormonal replacement therapy demonstrates a large endometrial fluid collection with a thin surrounding endometrium. She subsequently underwent surgical dilation for cervical stenosi s. (Levine D. The postmenopausal pelvis. In: Nyberg DA, ed. Transvaginal ultrasound. St. Louis, MO, Mosby Year Book, 1992:228) Endometrial Cancer Enlargement of the uterus is a late finding in endometrial cancer. This disease is discussed in more detail in Chapter 29. Bright Reflectors In The Uterus Causes of bright echoes in the uterus and endometrium are listed in (Table 28-12 ) . Uterine calcifications The most common cause of dense echoes in the uterus are calcifications resulting from fibroids. These appear as clumps of cal cification (Fig. 28-18A ) or as rim calcification around a mass. Figure - 28-18a. Uterine calcifications. Transvaginal transverse view of the uterus in a postmenopausal woman with abnormal bleeding demonstrates a well-defined echogenic focus with shadowing secondary to a calcified fibroid. Adjacent to this area is a fluid collection in a region of thickened endometrium (arrows). This was endometrial hyperplasia. A less common cause of calcification within the uterus is that of the arcuate artery. Arcuate artery calcifications are seen around the periphery ofthe uterus, usually in older women with severe medical problems such as diabetes, chronic renal failure, or hypertension. (21) Punctate calcifications occasionally are seen at the endometrial myometrial interface (see Fig. 28-18B ). These are probably secondary to a prior infection or procedure. (22)