Park Byung Kwan, Kim Chan Kyo, Kwon Ghee Young, Kim Jung Han
The Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-ku, Seoul, 135-710, South Korea.
Eur Radiol. 2007 Nov;17(11):2804-9. doi: 10.1007/s00330-007-0695-x. Epub 2007 Jun 5.
The purpose of this study was to retrospectively evaluate the enhancement washout and other imaging features of pheochromocytomas on delayed contrast-enhanced CT. Twenty-four patients with 31 pathologically confirmed pheochromocytomas were examined using unenhanced, early and delayed contrast-enhanced CT. The range of their APEW (absolute percentage of enhancement washout) or RPEW (relative PEW) values was analyzed. The other CT features including cystic or necrotic change, calcification, and hemorrhage were also determined by a pathologic correlation. Of the 31 pheochromocytomas, 10 (32%) had APEW values of 60% or less and RPEW values of 40% or less. Fourteen (45%) had APEW values >60% and RPEW values >40%. CT showed cystic or necrotic changes in 11 pheochromocytomas (35%) and calcification (10%) in 3. Nineteen pheochromocytomas showed cystic or necrotic changes on early contrast-enhanced CT, but eight of these lesions showed late enhancement on delayed contrast-enhanced CT, which pathologically corresponded to myxoid degeneration. The unenhanced CT showed hemorrhage in 23 pheochromocytomas, but the pathology examinations showed hemorrhage in 15 lesions. Many pheochromocytomas can be misdiagnosed as adenomas on CT due to the high enhancement washout values. Delayed contrast-enhanced CT can detect myxoid degeneration with late enhancement, which is seen as a cystic or necrotic change on early contrast-enhanced CT.
本研究的目的是回顾性评估嗜铬细胞瘤在延迟对比增强CT上的强化洗脱及其他影像特征。对24例患有31个经病理证实的嗜铬细胞瘤的患者进行了平扫、早期及延迟对比增强CT检查。分析了其APEW（绝对强化洗脱百分比）或RPEW（相对PEW）值的范围。还通过病理对照确定了其他CT特征，包括囊性或坏死性改变、钙化和出血。在31个嗜铬细胞瘤中，10个（32%）的APEW值≤60%且RPEW值≤40%。14个（45%）的APEW值>60%且RPEW值>40%。CT显示11个嗜铬细胞瘤（35%）有囊性或坏死性改变，3个有钙化（10%）。19个嗜铬细胞瘤在早期对比增强CT上显示囊性或坏死性改变，但其中8个病变在延迟对比增强CT上显示延迟强化，病理上对应黏液样变性。平扫CT显示23个嗜铬细胞瘤有出血，但病理检查显示15个病变有出血。由于强化洗脱值高，许多嗜铬细胞瘤在CT上可能被误诊为腺瘤。延迟对比增强CT可检测到延迟强化的黏液样变性，其在早期对比增强CT上表现为囊性或坏死性改变。
