白锥征white pyramid sign
原文：https://radiopaedia.org/articles/white-pyramid-sign-1
Medullary pyramids of kidney can be seen normally on unenhanced CT scans as high-attenuation structures and this is known as the white pyramid sign:
bilateral high-attenuation renal pyramids are an occasional incidental normal finding
unilateral appearance of white pyramids is subtle secondary sign suggestive of contralateral urinary tract obstruction
white pyramid sign:是指肾髓质的肾锥体在平扫CT上可见斑片状稍高密度影
双侧肾锥体的高密度影是偶然发现的正常征象
单侧肾锥体的高密度影可能提示继发于对侧尿路梗阻的征象
日常工作中经常碰见的一个肾脏CT表现，white pyramid sign没中文名称，意译为白锥征，主要是和髓质海绵肾鉴别，后者CT平扫表现为沿肾锥体呈放射状、簇状排列的多发小斑点状结石或钙化影、周围有小囊状或梭形低密度影，增强后扩张的集合管内结石周围有造影剂充盈，无结石的锥体集合管呈条纹状或小囊状造影剂积聚。
图片：
良性前列腺增生症手术治疗（一）｜不可忽视的经尿道前列腺切除术并发症
