P1130004

1-2.2 Corpora lutea

1-22.1 Sonographic images of corpora lutea

Useful uhraaomc features tn idemifying a corpus futrom aie its diaracteristic echogen icity, fts size and shape, as wefl as a thin hypoechoic border zonę which separatek 11 from ihe surrotindmg ovarian parenchyma (Fig, 1.21). On ułtrasound, fnteal tćssue shows up in yarymg gray tones which are typical of tbe refiections received brom k>ose. moderateły dense tissue, The sur-rounding ovarian parenchyma ts morę echogenkr_T due to fts higher density and łt eon tai ns many anechoic fol" Bdes. The shape of a corpus hiteum »trregular in many cases, sometimes evci) cubicat. It » often narrower near jts center_r resuhmg m a pear shape. Freęicntiy, venides which Ite adjacent to thc corpus luteum are the cause of these mdentahons to the outline of the corpus hiteum.

When 5 MHz scanners are used corpora haea are refatwefy reliabły detectable from their formation until mkłdiestrus around Day 12 of the cycie (Pterson and Ginther 1985 a). Thereafter they become less distmct At the time of luteofysis, approdmateh 14 to 16 days after ovulation, they are stfll detectable in many instances. Only rarely can the regressing corpus lute urn be klentified with certainty at the tbne of the foBowing ovulation or even a few days later (Ginther and Pier-son 1984 b). By this time fc will have become signif-icantly smaBer (Fig 1.22 and 1.23).