Department of Radiology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA.
Division of Anatomic Pathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
Abdom Radiol (NY). 2017 Oct;42(10):2447-2453. doi: 10.1007/s00261-017-1164-x.
To evaluate the imaging features of hepatic segmental atrophy and nodular elastosis.
In this Institutional review board (IRB)-approved, HIPAA-compliant study, we reviewed imaging features in six cases of histologically confirmed hepatic segmental atrophy (HSA) and nodular elastosis (NE). Retrospective review of ultrasound (US) in 2 patients, computed tomography (CT) in 5 patients, magnetic resonance imaging (MRI) in 4 patients, and positron emission tomography (PET) in 2 patients was performed. Location, size, and attenuation/density/signal intensity of these lesions were evaluated. Clinical presentation and coexistent conditions were also recorded.
All six patients were females. Mean age of presentation was 58.3 years (range 37-80). A single HSA and NE lesion in each patient was found. The mean size of the lesion was 18 mm (range: 3 mm to 36 mm). Most lesions were detected incidentally (5/6). On contrast-enhanced single-phase (portal venous) CT, most lesions were hypodense (4/5) and one lesion was hyperdense to fatty liver parenchyma. On MRI, the lesions were iso- to hyperintense on T2-weighted images, T1 hypointense, and hyperintense on diffusion-weighted images (DWI). Three lesions were hypointense on arterial, portal venous, and delayed phases. One lesion occurring in fatty liver appeared hyperintense on all three phases. Gd-EOB-DTPA-enhanced images were available in 2 patients and lesions were hypointense on the 20-min hepatobiliary phase. On PET, two lesions were isometabolic to the background hepatic parenchyma. On ultrasound, one lesion appeared hypoechoic and another lesion isoechoic to hepatic parenchyma.
Hepatic segmental atrophy and nodular elastosis is an uncommon benign lesion and can simulate metastases due to variable imaging features. Lack of FDG uptake on PET/CT may be a clue to the benign nature of the lesion and may suggest the possibility of HSA and NE.
评估肝段萎缩和结节性弹性组织增生的影像学特征。
本研究经机构审查委员会（IRB）批准，符合 HIPAA 规定，回顾性分析了 6 例经组织学证实的肝段萎缩（HSA）和结节性弹性组织增生（NE）患者的影像学特征。对 2 例患者的超声（US）、5 例患者的计算机断层扫描（CT）、4 例患者的磁共振成像（MRI）和 2 例患者的正电子发射断层扫描（PET）进行了回顾性分析。评估了这些病变的位置、大小、衰减/密度/信号强度。还记录了临床表现和并存情况。
所有 6 例患者均为女性，平均发病年龄为 58.3 岁（范围 37-80 岁）。每位患者均发现单个 HSA 和 NE 病变，病变平均大小为 18mm（范围 3-36mm）。大多数病变为偶然发现（5/6）。在单期（门静脉期）增强 CT 上，大多数病变为低密度（4/5），1 个病变的密度高于脂肪性肝实质。在 MRI 上，病变在 T2 加权图像上呈等至高信号，T1 呈低信号，在弥散加权图像（DWI）上呈高信号。3 个病变在动脉期、门静脉期和延迟期呈低信号。1 个发生在脂肪肝中的病变在所有 3 个时相均呈高信号。2 例患者行钆塞酸二钠增强 MRI 检查，病变在 20 分钟肝胆期呈低信号。在 PET 上，2 个病变与背景肝实质的代谢率相同。在超声上，1 个病变呈低回声，另 1 个病变与肝实质回声相等。
肝段萎缩和结节性弹性组织增生是一种不常见的良性病变，由于其影像学特征的多样性，可能模拟转移瘤。PET/CT 上无 FDG 摄取可能是病变良性的线索，并可能提示 HSA 和 NE 的可能性。
