1·Duodenal diverticulum manifested as hemicycle lesion with gaseous density which had air-fluid level behind pancreatic head with clear border.
憩室表现为胰头右后方半圆形含气体腔影，可有液平，与胰头交界部边缘锐利。
2·Oviduct is located besides of unfix side of ovary that forms a hemicycle around ovary.
输卵管位于卵巢游离缘外侧，呈半圆形围绕着卵巢，输卵管壶腹部弯曲、峡部直；
3·Once the aquifer disconnect from the stream, the inverted saturated zone of the rectangular streambed show a hemicycle, and that of rectangular streambed show a vertical rhombus.
当河流与地下水脱节后，矩形河床的悬挂饱水带呈半圆形，三角形河床的悬挂饱水带呈直立菱形。