Ba-Ssalamah Ahmed, Schima Wolfgang, Schmook Maria T, Linnau Ken F, Schibany Nadja, Helbich Thomas, Reimer Peter, Laengle Friedrich, Wrba Friedrich, Kurtaran Amir, Ryan Mark, Mann Frederick A
Department of Radiology, University of Vienna, Waehringer Gürtel 18-20, A-1090 Vienna, Austria.
AJR Am J Roentgenol. 2002 Dec;179(6):1447-56. doi: 10.2214/ajr.179.6.1791447.
The objective of our study was to describe the functional and differential uptake features of atypical focal nodular hyperplasia using different MR contrast agents and to evaluate their potential role in the diagnosis and characterization of focal nodular hyperplasia.
Contrast-enhanced MR images of 45 patients with 85 focal nodular hyperplasia lesions were retrospectively reviewed. In these patients, sonographic findings were nonspecific (n = 37), or CT features were inconclusive (n = 8). Non-liver specific gadolinium chelates were used in 18 patients (48 lesions) suspected of having either focal nodular hyperplasia or hemangioma. The following liver-specific agents were used in patients with suspected focal nodular hyperplasia or metastases: mangafodipir trisodium, 30 patients (55 lesions); ferumoxides, six patients (16 lesions); and SHU 555 A, six patients (six lesions). Individual lesions were quantified by signal intensity and assessed qualitatively by homogeneity, contrast enhancement, and presence of a central scar.
At unenhanced MR imaging, the triad of homogeneity, isointensity, and central scar was found in 22% of the focal nodular hyperplasia lesions. On mangafodipir trisodium-enhanced T1-weighted images, all focal nodular hyperplasia lesions showed contrast uptake: in 64% of the lesions, uptake was equal to parenchyma; 25%, greater than the parenchyma; and 11%, less than the parenchyma. On iron oxide-enhanced T2-weighted images, all focal nodular hyperplasia lesions showed uptake of the contrast agent, but contrast uptake in the lesions was less than in the surrounding parenchyma. Dynamic gadolinium chelate-enhanced MR imaging showed early and vigorous enhancement of focal nodular hyperplasia lesions with rapid washout in 88%. Atypical imaging features of the lesions included hyperintensity on T1-weighted images, necrosis and hemorrhage, and inhomogeneous or only minimal contrast uptake.
For patients in whom the diagnosis of focal nodular hyperplasia cannot be established on unenhanced or gadolinium-enhanced MR imaging, homogeneous uptake of liver-specific contrast agent with better delineation of central scar may help to make a confident diagnosis of focal nodular hyperplasia.
本研究的目的是利用不同的磁共振对比剂描述非典型性局灶性结节性增生的功能及不同的摄取特征，并评估它们在局灶性结节性增生的诊断和特征描述中的潜在作用。
回顾性分析45例患者85个局灶性结节性增生病灶的对比增强磁共振图像。在这些患者中，超声检查结果不具有特异性（n = 37），或CT特征不明确（n = 8）。18例怀疑患有局灶性结节性增生或血管瘤的患者使用了非肝脏特异性钆螯合物（48个病灶）。怀疑患有局灶性结节性增生或转移瘤的患者使用了以下肝脏特异性对比剂：钆喷酸葡胺，30例患者（55个病灶）；超顺磁性氧化铁，6例患者（16个病灶）；以及SHU 555 A，6例患者（6个病灶）。通过信号强度对单个病灶进行量化，并通过均匀性、对比增强和中央瘢痕的存在进行定性评估。
在未增强的磁共振成像中，22%的局灶性结节性增生病灶表现出均匀性、等信号和中央瘢痕三联征。在钆喷酸葡胺增强的T1加权图像上，所有局灶性结节性增生病灶均显示对比剂摄取：64%的病灶摄取与实质相等；25%的病灶摄取大于实质；11%的病灶摄取小于实质。在超顺磁性氧化铁增强的T2加权图像上，所有局灶性结节性增生病灶均显示对比剂摄取，但病灶内的对比剂摄取低于周围实质。动态钆螯合物增强磁共振成像显示88%的局灶性结节性增生病灶早期强化明显且迅速廓清。病灶的非典型成像特征包括T1加权图像上的高信号、坏死和出血，以及不均匀或仅轻微的对比剂摄取。
对于在未增强或钆增强磁共振成像上无法确诊局灶性结节性增生的患者，肝脏特异性对比剂的均匀摄取以及中央瘢痕的更好显示可能有助于确诊局灶性结节性增生。
