42e Figure -28-4b (B)View of the right renal fossa demonstrates an absent right kidney. 签 endometrium The endometrium is visualized as a hyperechoic band in the centerof the uterus. The total thickness of the endometrium re presents the anterior a nd posterior opposed layers. Endovaginal scanning is required to optimally visualize the endometrium. [28.5 ] When endometrial fluid is present, this should not be included in the endometrial thickness measurement. The hypoechoic la yer around the endometrium represents an inner compact layer of myometrium and should not be included in endometrial thickness measurements (4) Normal endometrial thickness and appea rance varies with the phase of the menstrual cycle (5)( Fig. 28-5A, Fig. 28-5B and Table 28-3). During the menstrual hase, hypoechoic mate rial can be seen centrally, which represents blood and tissue. In the proliferative phase the endometrium has the appea rance ofthree lines ith an echogenic central line surrounded by a more hypoechoic layer, with a peripheral hyperechoic layer. In the late secretory phase, the endometrium is at its greatestthickness, with homogeneously increased echogenicity and increased through transmission (6) ure-28-5a Normal endometrium. "Triple line"e ndometriumin midcycle Secretory phase endometrium that is thick and echogenicwith postenor acoustic enhancement Fallopian Tub The normal fallopiantube is difficult to distinguish from surrounding vessels and ligaments. It usually is not visualized unless abnormal or surrounded by fluid Ovarian Size Ovaries in girls younger than 2 years of age are typically less than 1 mL in volume, although in neonates they can be slightly larger. Recent literature alsoFigure - 28-4b. (B) View of the right renal fossa demonstrates an absent right kidney. Endometrium The endometrium is visualized as a hyperechoic band in the center of the uterus. The total thickness of the endometrium represents the anterior a nd posterior opposed layers. Endovaginal scanning is required to optimally visualize the endometrium. [28.5 ] When endometrial fluid is present, this should not be included in the endometrial thickness measurement. The hypoechoic layer around the endometrium represents an inner compact layer of myometrium and should not be included in endometrial thickness measurements. (4) Normal endometrial thickness and appearance varies with the phase of the menstrual cycle (5) ( Fig. 28-5A , Fig. 28-5B , and Table 28-3 ). During the menstrual phase, hypoechoic material can be seen centrally, which represents blood and tissue. In the proliferative phase, the endometrium has the appearance of three lines with an echogenic central line surrounded by a more hypoechoic layer, with a peripheral hyperechoic layer. In the late secretory phase, the endometrium is at its greatest thickness, with homogeneously increased echogenicity and increased through transmission. (6) Figure - 28-5a. Normal endometrium. "Triple line" endometrium in midcycle. Figure - 28-5b Secretory phase endometrium that is thick and echogenic with posterior acoustic enhancement. Fallopian Tube The normal fallopian tube is difficult to distinguish from surrounding vessels and ligaments. It usually is not visualized unless abnormal or surrounded by fluid. Ovaries Ovarian Size Ovaries in girls younger than 2 years of age are typically less than 1 mL in volume, although in neonates they can be slightly larger. Recent literature also