Abstract：
Malignant splenic lesions in dogs are common, with hemangiosarcoma diagnosed most frequently, and there have been no consistent clinicopathologic, gross, or imaging characteristics identified that differentiate malignant from benign splenic lesions. Histopathology is required for definitive diagnosis, and given the poor long-term prognosis of malignant splenic lesions, a noninvasive tool to aid in diagnosis would be valuable. This prospective cohort study utilized gadoxetate disodium, a liver-specific contrast agent (Gd-EOB-DPTA; Eovist), to identify the general lesion and pre- and postcontrast signal characteristics of benign and malignant splenic and hepatic lesions in dogs with naturally occurring disease. Twenty-five dogs were enrolled, Eovist-enhanced MRI was performed, and dogs were taken to surgery for splenectomy and other organ biopsy. All histopathology and MRI studies were evaluated by a single pathologist and a single radiologist, respectively. The associations between the tumor type and numerous variables defined on MRI were evaluated using Fisher\'s exact tests, and the significance was identified at a P-value of .05. Malignant splenic masses were identified in 11/25 (44%) dogs, and 5/11 malignancies represented hemangiosarcoma. The presence of abdominal effusion (P = .017) and the presence of hepatic nodules on MRI (P = .009) were associated with splenic malignancy. There were no benign T2 hyperintense and no malignant T2 hypointense lesions (P = .021). Utilization of the T2 W MRI sequence may aid in the identification of malignant splenic lesions, particularly when accompanied by abdominal effusion and hepatic lesions.
摘要：
狗的恶性脾病变很常见，最常诊断为血管肉瘤，没有一致的临床病理，gross,或影像学特征确定区分恶性和良性脾病变。明确诊断需要组织病理学,鉴于恶性脾病变的长期预后差，辅助诊断的非侵入性工具将是有价值的。这项前瞻性队列研究利用gadoxetate二钠，肝脏特异性造影剂（Gd-EOB-DPTA；Eovist），明确自然发生疾病犬脾、肝良性和恶性病变的一般病变和造影前后信号特征。25只狗被录取了，进行了Eovist增强MRI，和狗被带到手术进行脾切除和其他器官活检。所有组织病理学和MRI研究均由一名病理学家和一名放射科医生进行评估。分别。使用Fisher精确检验评估肿瘤类型与MRI上定义的众多变量之间的关联。并且在P值为0.05时确定了显著性。在11/25（44％）的狗中发现了恶性脾肿块，5/11恶性肿瘤代表血管肉瘤。腹腔积液的存在（P=0.017）和MRI上肝结节的存在（P=.009）与脾恶性肿瘤有关。无良性T2高信号和恶性T2低信号病变（P=.021）。利用T2WMRI序列可以帮助识别恶性脾病变，特别是伴有腹腔积液和肝脏病变时。
