Kanematsu M, Kondo H, Enya M, Yokoyama R, Hoshi H
Department of Radiology, Gifu University School of Medicine, Tsukasamachi, Japan.
AJR Am J Roentgenol. 1998 Aug;171(2):445-8. doi: 10.2214/ajr.171.2.9694472.
The purpose of our study was to assess the frequency and imaging characteristics of nonpathologic portal perfusion defects in subcapsular liver parenchyma adjacent to the right ribs as seen on CT hepatic arteriography combined with helical CT during arterial portography (CTAP).
From January 1994 to June 1997, helical CTAP and CT hepatic arteriography were performed in 94 patients with suspected malignant hepatic tumors. The patient group comprised 66 men and 28 women ranging from 37 to 83 years old (mean, 64 years old). Three radiologists retrospectively reviewed the images obtained by CTAP to evaluate portal perfusion defects adjacent to the right ribs for location, shape, size, and correlation with findings seen on CT hepatic arteriography.
We identified 16 nonpathologic portal perfusion defects adjacent to the right eighth (n = 1), ninth (n = 12), and tenth (n = 3) ribs in 12 (13%) of 94 patients. The shapes of the 16 defects were circular (n = 1), oval (n = 7), wedge (n = 3), and irregular (n = 5). The defects were 10-30 mm in diameter (mean, 16.9 mm). In four (25%) of 16 locations, CT hepatic arteriography showed poorly identified, homogeneous, irregularly shaped areas of contrast enhancement corresponding to the defects seen on CTAP. The portal perfusion defects were proven to be nonpathologic on definitive surgery in four patients and on follow-up radiography in eight patients.
Helical CTAP may show nonpathologic portal perfusion defects adjacent to the right ribs. Most defects did not appear circular but rather were oval, irregular, or wedge-shaped. CT hepatic arteriography infrequently showed corresponding findings. Radiologists should recognize this potential pitfall when interpreting images obtained by helical CTAP.
本研究的目的是评估在动脉门静脉造影（CTAP）期间，结合螺旋CT的CT肝动脉造影中，右肋附近肝包膜下肝实质内非病理性门静脉灌注缺损的频率和影像特征。
1994年1月至1997年6月，对94例疑似恶性肝肿瘤患者进行了螺旋CTAP和CT肝动脉造影检查。患者组包括66名男性和28名女性，年龄在37至83岁之间（平均64岁）。三名放射科医生回顾性地审查了CTAP获得的图像，以评估右肋附近门静脉灌注缺损的位置、形状、大小以及与CT肝动脉造影所见结果的相关性。
我们在94例患者中的12例（13%）中，发现了与右第八（n = 1）、第九（n = 12）和第十（n = 3）肋相邻的16个非病理性门静脉灌注缺损。16个缺损的形状为圆形（n = 1）、椭圆形（n = 7）、楔形（n = 3）和不规则形（n = 5）。缺损直径为10 - 30 mm（平均16.9 mm）。在16个位置中的4个（25%），CT肝动脉造影显示与CTAP上所见缺损相对应的、难以辨认的、均匀的、形状不规则的对比增强区域。在4例患者的确定性手术和8例患者的随访影像学检查中，门静脉灌注缺损被证实为非病理性。
螺旋CTAP可能显示右肋附近的非病理性门静脉灌注缺损。大多数缺损并非圆形，而是椭圆形、不规则形或楔形。CT肝动脉造影很少显示相应的发现。放射科医生在解读螺旋CTAP获得的图像时应认识到这一潜在陷阱。
