肾平滑肌肉瘤的CT表现

目的:探讨肾平滑肌肉瘤的CT表现。方法:对5例经病理证实的肾平滑肌肉瘤的CT征象进行回顾性分析。结果:5例肿块最大径均>5cm。CT平扫示1例呈均匀高密度,2例呈等密度,2例呈高低混杂密度。增强扫描时1例呈均匀强化,4例肿块呈不均匀强化,其内见明显的坏死、囊变征象。结论:肿块巨大、坏死囊变明显及肿块内出血为肾平滑肌肉瘤的主要CT表现,但其CT及临床表现均与肾癌相似,术前鉴别困难,最终确诊依靠病理学检查。     

US, CT, and MR evaluation of accessory renal arteries and proximal renal arterial branches

RATIONALE AND OBJECTIVES: The purpose of this study was to compare color Doppler ultrasound (US), computed tomographic (CT) angiography, and magnetic resonance (MR) angiography for the evaluation of accessory renal arteries and proximal branches of the main renal artery. MATERIALS AND METHODS: Fifty-six subjects who had undergone conventional arteriography of the renal arteries participated in a prospective comparison of Doppler US (45 patients), CT angiography (52 patients), and nonenhanced MR angiography (28 patients). Conventional arteriography depicted 28 accessory renal arteries and 21 proximal branches of the main renal artery within 2 cm of the aorta. RESULTS: US depicted five of 24 accessory renal arteries seen at arteriography but no proximal arterial branches. CT angiography depicted 24 of 26 accessory renal arteries and 13 of 17 proximal arterial branches, as well as 15 additional accessory renal arteries not seen at conventional arteriography. MR demonstrated 11 of 15 accessory arteries, as well as four additional accessory arteries not seen at conventional arteriography. MR did not depict any of nine proximal arterial branches seen at conventional arteriography. CONCLUSION: When compared with US or nonenhanced MR angiography, CT is the preferred method for evaluation of accessory renal arteries and proximal branches of the renal artery.     

Puerperal ovarian vein thrombosis: evaluation with CT, US, and MR imaging

Five women suspected of having puerperal ovarian vein thrombosis (POVT) were examined with either computed tomography (CT) (five patients), ultrasonography (US) (three patients), magnetic resonance (MR) imaging (one patient), or a combination of these modalities. CT findings included tubular retroperitoneal mass (five patients), periuterine mass (four patients), enlarged uterus (four patients), fluid in the uterus (five patients), central ovarian vein thrombus (four patients), inferior vena cava thrombus (one patient), right hydroureter (one patient), and right ureteral compression (one patient). US findings were similar to CT findings except for an inability to demonstrate the right hydroureter and ureteral compression. MR imaging demonstrated the retroperitoneal mass and central ovarian vein thrombus. CT proved to be superior for the initial evaluation and subsequent diagnosis of POVT. US was useful for follow-up examinations, and MR imaging results confirmed a case of POVT that was suspected following CT.     

Cross-sectional imaging of idiopathic solitary renal vein varix: report of two cases

Two cases of solitary renal vein varices are reported which presented as incidental findings on abdominal computed tomography (CT) and were initially thought to represent retroperitoneal lymph nodes. Contrast-enhanced CT, magnetic resonance imaging (MRI), and Doppler ultrasound (US), all demonstrated the vascular nature of these masses suggesting the correct diagnosis. When a rounded soft tissue density mass is seen on noncontrast-enhanced CT either in or contiguous to the renal hilum, a renal vein varix must be excluded. Doppler US, MRI, or dynamic contrast-enhanced CT should be done to exclude a renal varix as the cause.     

Cross-sectional imaging of idiopathic solitary renal vein varix: Report of two cases

Two cases of solitary renal vein varices are reported which presented as incidental findings on abdominal computed tomography (CT) and were initially thought to represent retroperitoneal lymph nodes. Contrast-enhanced CT, magnetic resonance imaging (MRI), and Doppler ultrasound (US), all demonstrated the vascular nature of these masses suggesting the correct diagnosis. When a rounded soft tissue density mass is seen on noncontrast-enhanced CT either in or contiguous to the renal hilum, a renal vein varix must be excluded. Doppler US, MRI, or dynamic contrast-enhanced CT should be done to exclude a renal varix as the cause.     

双排螺旋CT在前胡桃夹综合征诊断中的应用价值

目的:探讨双排螺旋CT在前胡桃夹综合征诊断中的应用价值。方法:回顾性分析6例经临床诊断为前胡桃夹综合征患者的双排螺旋CT影像学资料及临床资料。结果:6例前胡桃夹综合征均显示肠系膜上动脉压迫左肾静脉征象:腹主动脉与肠系膜上动脉之间夹角平均为18°;左肾静脉穿肠系膜上动脉夹角时明显受压,其前后径受压前后之比约4:1;其中2例显示左侧精索静脉扩张,1例显示左侧卵巢静脉扩张。结论:综合应用双排螺旋CT平扫、增强扫描及多种图像后处理技术能够清楚显示腹主动脉和肠系膜上动脉与受压的左肾静脉三者之间的解剖关系,并能发现增强扫描平衡期双肾实质密度差异及精索静脉或卵巢静脉曲张等表现,可作为前胡桃夹综合征确诊的一种重要手段。     

Comparison of Ultrasound,CT, and MR Imaging in the Evaluation of Candidates for TIPS

To compare ultrasound (US), CT, and MRI in the evaluation of hepatic vascular anatomy, portal and splenic venous flow, and collateral pathways (varices and spontaneous shunts) in candidates for transjugular intrahepatic portosystemic shunting (TIPS), 17 patients with history of refractory variceal bleeding or intractable ascites underwent duplex US, contrast-enhanced CT, and MRI before TIPS. The appearance of portal and hepatic anatomy was graded from 1 (not visible) to 4 (excellent visualization) independently by four radiologists. Presence and direction of portal and splenic venous flow, and presence and location of varices and spontaneous portosystemic shunts were also assessed. Results and effects of interobserver variation were assessed for significance using Friedman's ANOVA and Wilcoxon's signed-rank test. MRI yielded higher scores than CT or US for hepatic veins (P <.0001) and inferior vena cava (P <.0001). MRI and CT scored better than US for portal vein branches (P =.012) and splenic vein (P =.0038). All tests demonstrated the main portal vein well, with no statistically significant difference. US and MRI were more sensitive than CT for detecting portal vein flow and direction (US 76%, CT 0%, MRI 82%). MRI was most sensitive for splenic vein flow and direction (US 41%, CT 0%. MRI 76%). CT and MRI were more sensitive than US in detecting varices (US 5%, CT 50%, MRI 58%) and spontaneous shunts (US 13%, CT 75%, MRI 75%). Interobserver variation did not influence results significantly P =.3691). MRI provides the most useful information and may be the preferred single imaging test prior to TIPS.     

钝性肾外伤的多层螺旋CT诊断

目的探讨钝性肾外伤的多层CT检查方法和影像诊断。方法对病例资料完整的28例钝性肾外伤的肾脏,多层CT双肾平扫及增强后28 s、60 s、3~5 min三期(皮质期、实质期和肾盂期)扫描后详细观察分析。结果28例患肾中肾实质挫伤水肿8例,肾实质挫伤并肾实质内出血6例,肾实质撕裂11例,合并肾周尿液外漏5例;肾实质碎裂伴肾盂肾盏撕裂伤致肾盂肾盏积血2例,肾蒂血管撕裂伤1例。增强CT可直接显示肾实质裂口,并明确和鉴别包膜内、外肾周出血。增强CT肾脏分泌期观察到对比剂漏出是诊断尿漏的直接征象,且CTU可显示整个漏出路径;通过CTA技术非常直观地再现肾脏供血动脉及肾静脉形态、走形及裂口,对肾蒂撕裂的诊断有独特价值。结论多层螺旋CT具有快速扫描和优良图像分辨率,辅之以多种图像后处理技术,对钝性肾脏外伤的诊断有着重要的优势。     

Malignant stromal tumors of the small intestine: report of 9 cases

PURPOSE: Analysis of imaging features of malignant stromal tumors of the small bowel and review of literature. MATERIAL AND METHODS: 9 cases of malignant stromal tumor of the small bowel with histological proof were imaged at US (8 cases), small bowel series (9 cases) and CT scan (3 cases). RESULTS: There were 6 cases of leiomyosarcoma and 3 cases of malignant schwannoma. Tumors involved the jejunum in 3 patients, the ileum in 4 patients, and the duodenum in 2 patients. The main clinical presentation was an abdominal mass (8 cases), which appeared heterogeneous and hypoechoic with eccentric lumen at US confirming its GI origin (7 cases). Small bowel series showed a bulky cavitary mass opacified via a thin fistula (7 cases), an ileo-ileal intussusception (1 case) and enlarged duodenal lumen (1 case). CT performed in 3 cases showed an intraperitoneal mass with soft-tissue density. A communication with the GI tract was noted in 1 case, and in another case, it showed an intestinal intussusception. US guided biopsy performed in 3 cases provided diagnosis in 2 cases (malignant schwannoma, leiomyosarcoma). Tumor growth was exophytic in 8 cases and dumbbell-shaped in 1 case. CONCLUSION: The imaging features of malignant stromal tumors of the small bowel are similar. It varies with the type of tumor growth and its size. The diagnosis may be suggested based on imaging features.     

Rectal malignant stromal tumor (leiomyosarcoma): echoendoscopic, computed tomographic aspects and anatomopathologic correlations]

We report the CT and endorectal us features of a malignant stromal tumor of the rectum (leiomyosarcoma). On CT scan, rectal leiomyosarcoma appeared as a large soft tissue mass, arising from the anterior rectal wall with exorectal extension. On endorectal US, the rectal leiomyosarcoma presented as a well-defined hypoechogenic and heterogeneous mass arising from the rectal muscularis propria. The uncommon location of leiomyosarcoma to the rectum may simulate other rectal tumors such as adenocarcinoma on CT. As suggested by this report, endorectal us demonstrated the muscular origin of the tumor.     

Renal sarcoma and sarcomatoid renal cell carcinoma: CT and angiographic features

Computed tomographic (CT) and angiographic findings in 14 patients (eight men, six women, aged 30-72 years) with sarcomatoid renal cell carcinoma (SRCC) and various types of renal sarcoma are described. There were four patients with SRCC; three, leiomyosarcoma; two, liposarcoma; two, fibrosarcoma; and one each of unclassified renal sarcoma, clear cell sarcoma, and malignant fibrous histiocytoma. The most frequent presenting symptom was an abdominal mass or pain. All 14 patients underwent CT, and 11 underwent selective renal angiography. The diagnosis of renal sarcoma should be suspected when CT findings suggest that the tumor arises from the renal capsule or renal sinus and when the tumor is hypovascular or avascular on angiograms. The characteristic negative attenuation values for liposarcomas permit a specific diagnosis. Sarcomas that originate in the renal parenchyma and SRCC cannot be easily differentiated from renal cell carcinoma; however, renal sarcomas do not appear to have a propensity for extension into the renal vein or the inferior vena cava.     

Primary Renal Leiomyosarcoma Presenting with Subcutaneous and Osseous Metastases: Staging and Follow-Up with 18F-FDG PET/CT

A 60 year old woman who presented with multiple small subcutaneous nodules in the upper back and arms, was referred for an [18F] fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) after histological evaluation revealed metastatic leiomyosarcoma of unknown origin. The PET/CT showed multiple ¹⁸F-FDG-avid subcutaneous nodules, bone lesions, as well as a large left renal mass, which was biopsied to confirm a primary renal leiomyosarcoma arising from the renal parenchyma. A post therapy PET/CT showed overall progression of disease. The use of ¹⁸F-FDG PET/CT in the staging and evaluation of response to therapy of a renal leiomyosarcoma has not been previously described in the literature.     

CT Angiography for Living Kidney Donors: Accuracy, Cause of Misinterpretation and Prevalence of Variation

OBJECTIVE: To determine the accuracy of the use of multi-detector row CT (MDCT) to predict vascular anatomy in living kidney donors and to reveal the prevalence of vascular variations in a Korean population. MATERIALS AND METHODS: A total of 153 living kidney donors that had undergone preoperative CT and nephrectomy, either with open or laparoscopic surgery, were selected retrospectively. The initial CT results were compared with the surgical findings and repeated review sessions of CT scans were performed to determine the causes of mismatches in discordant cases. RESULTS: The accuracy of CT angiography was 95% to predict the number of renal vessels. Four arteries and two veins were missed during the initial CT interpretation due to perception errors (for two arteries and two veins) and technical limitations (two arteries). The prevalence of multiple renal arteries and veins, early branching of a renal artery and late confluence of a renal vein were 31%, 5%, 12%, 17%, respectively. The circumaortic renal vein and the bilateral inferior vena cava were found in two cases each (1.3%). One case (0.7%) each of a retroaortic renal vein and a supradiaphragmatic originated renal artery were found. CONCLUSION: MDCT provides a reliable method to evaluate the vascular anatomy and variations of living kidney donors.     

Leiomyosarcoma of the popliteal vein

Primary vascular leiomyosarcomas are rare tumors arising from the media of vessel walls, involving the extremities in about one third of reported cases, and the popliteal vein even less frequently. We report a case of popliteal vein leiomyosarcoma in a 62-year old man who presented with leg pain and edema 4 weeks following spine surgery. Findings on ultrasound, MRI and CT angiography are reviewed, with particular emphasis on the value of CT angiography in fully evaluating the extent of the mass and in assisting percutaneous biopsy.     

CT evaluation of renovascular disease.

Computed tomography (CT) plays an important role in evaluation and management of primary renovascular disease. Nonenhanced CT is useful for demonstrating renal hemorrhage, renal parenchymal or vascular calcifications, and masses. Contrast material-enhanced CT is essential to identify global or regional nephrographic abnormalities resulting from the vascular process (eg, renal infarcts, ischemia secondary to renal artery stenosis, arteriovenous communications). In addition, renal manifestations of a systemic disease (eg, vasculitis, thromboembolic disease) can be seen at CT. In trauma, occlusion of the main renal artery can be accurately diagnosed with contrast-enhanced CT. In cases of spontaneous renal hemorrhage without an apparent cause (eg, vasculitis, coagulopathy), a careful CT study should be performed to exclude renal cell carcinoma. The presence of fat in a hemorrhagic renal mass larger than 4 cm in diameter is characteristic of angiomyolipoma complicated by hemorrhage. Acute renal vein thrombosis appears as a clot in a distended renal vein, whereas renal vein retraction with collateral vessels is highly indicative of chronic thrombosis. Helical CT, especially with multiplanar two-dimensional and three-dimensional reconstruction following an intravenous injection of iodinated contrast material, has greatly improved our ability to directly image the proximal renal arteries and detect vascular lesions.     

下腔静脉畸形的64层螺旋CT表现

目的 探讨64层螺旋CT下腔静脉畸形的影像表现.方法 回顾性分析6986例受检者的腹部64层螺旋CT增强扫描资料,共发现25例下腔静脉先天畸形.分析下腔静脉畸形的影像表现.结果 25例下腔静脉畸形中包括左下腔静脉6例,CT表现为肾下段腹主动脉左侧上行的下腔静脉.双下腔静脉10例,CT表现为肾下段腹主动脉两侧上行的下腔静脉.左肾静脉畸形5例,CT增强扫描横断面显示腹主动脉后和环主动脉走行的左肾静脉.肝下段下腔静脉中断伴奇静脉延续2例,胸腹部CT增强扫描显示肝段至肾上段下腔静脉缺如,肾段下腔静脉由奇静脉延续回流人上腔静脉,而肝静脉直接回流右心房.腔静脉血管造影见对比剂经增粗的奇静脉和半奇静脉通过上腔静脉回流右心房.肝下段下腔静脉中断伴门静脉延续1例,增强CT显示下腔静脉直接与门静脉在肝门部连接,肝门部门静脉呈瘤样扩张.左下腔静脉伴半奇静脉延续1例,增强CT可见左下腔静脉与半奇静脉连接,上行汇入奇静脉.结论 64层螺旋CT可清晰显示下腔静脉及其属支的畸形,可成为下腔静脉畸形的重要诊断方法.     

黏液样小管状及梭形细胞肾癌的CT诊断

目的：探讨黏液样小管状及梭形细胞肾癌（MTSRCC）的 CT 表现,提高对该病的认识。方法：回顾性分析8例经手术病理证实的 MTSRCC 的 CT 表现,8例均行 MSCT 平扫及三期增强扫描。分析病灶大小、位置、形态、平扫密度、强化方式和程度、有无周边侵犯、淋巴结和远处转移等征象。结果：8例 MTSRCC 均为单发病灶,CT 上表现为边界清晰的类圆形或椭圆形肿块,最大直径平均为4．53 cm（1．8～7．6 cm）,平扫7例呈等或稍高密度,1例呈低密度,1例伴同侧肾结石,均未见出血和钙化。增强扫描肿瘤呈渐进性轻度强化,6例呈均匀强化,2例呈不均匀强化,其强化程度明显低于正常肾脏皮质,8例皮髓质期和延迟期平均 CT 值分别增加26．2 HU 和33．6 HU,肿瘤与肾皮质的强化比值皮髓质期和延迟期分别为21．54％和33．28％。结论：MTSRCC 为好发于成年女性的较罕见低度恶性肿瘤,在 CT 上表现为边界清晰、出血坏死及钙化少见的规则肿块,可伴有同侧肾结石,具有平扫以等密度为主,渐进性轻度强化的特点。     

Radiologic Findings of Renal Inflammatory Pseudotumor: A Case Report

Renal inflammatory pseudotumor is a very rare benign condition of unknown etiology characterized by proliferative myofibroblasts, fibroblasts, histiocytes, and plasma cells. In the case we report, the lesion appeared on contrast-enhanced power Doppler US images as a well-defined hypoechoic mass with intratumoral vascularity, and on CT as a low-attenuated mass. Differentiation from malignant renal neoplasms was not possible.     

螺旋CT扫描在小肾癌诊断中的应用价值(附14例报告)

目的探讨螺旋CT多期扫描在小肾癌诊断中的价值。方法收集经手术病理证实的小肾癌14例,行螺旋CT平扫和皮质期、实质期及肾盂期增强扫描,分析其表现。结果CT平扫病灶呈等密度9例,稍低密度4例,稍高密度1例,2例为囊实性肿块,其中1例伴斑点状钙化。增强扫描皮质期11例呈明显强化,3例呈轻中度强化。肾实质期肿瘤密度迅速减退,肾盂期肿瘤密度进一步减退。结论小肾癌螺旋CT增强多期扫描征象有一定的特征性,对小肾癌的诊断有重要价值。     

Retroaortic left renal vein with renal vein hypertension causing hematuria

We describe a case of retroaortic left renal vein with hematuria. In this case, pullback pressure from the retroaortic left renal vein to the inferior vena cava revealed left renal vein hypertension according to criteria of the “nutcracker phenomenon.” We stress that left renal vein anomaly including retroaortic left renal vein can cause clinical symptoms such as hematuria.