MR of vascular encasement in parasellar masses: comparison with angiography and CT

The relationship between tumor mass and vascular involvement as seen on MR imaging was examined in 11 patients with masses in the parasellar region, and the findings were correlated with CT and angiography. In six cases, MR was superior to CT and angiography in depicting the relationship of the tumor to adjacent blood vessels. In these cases, MR demonstrated tumor surrounding the blood vessel without changing the diameter of its lumen. Angiography did not reveal encasement in these cases. In four cases, both MR and angiography showed signs of vascular encasement with narrowing of the vessel's lumen. In two cases, MR was equivocal while angiography revealed vascular encasement in one case and was negative for encasement in the other. CT was less sensitive than MR in defining vascular encasement since there is usually little contrast between an enhancing tumor and the major blood vessels. Coronal scanning appeared to be the best plane of imaging and correlated well with the anteroposterior angiogram. We propose that MR is the method of choice for evaluating arterial encasement by tumors and may obviate the need for angiography in those cases in which MR is positive for a basal lesion.     

Myxoma of the mandible

 Myxoma of the jaw bone is a peculiar and rare tumor. A case of myxoma of the mandible is described in a 38-year-old man. The plain X-ray showed multiple osteolytic destructive lesions in the molar root area. CT scans demonstrated osteolytic expansile lesions with mild enhancement of the solid portion of the mass. Histologically, the tumor is composed of plump stellate cells with abundant amorphous myxoid stroma.     

外周性原始神经外胚层瘤的影像表现

目的:探讨外周性原始神经外胚层肿瘤的影像学表现.方法:回顾性分析经病理证实的12例外周性神经外胚层瘤的影像学资料.9例行CT扫描,4例行MR扫描,其中1例行DSA检查.结果:胸壁软组织5例,右肺下叶1例,肱骨2例,股骨1例,胫骨1例,脊椎2例.胸壁软组织的pPNETs CT平扫表现为大而边界欠清的软组织肿块,内见坏死,无钙化,增强后明显不均匀强化.右肺下叶的pPNETs CT平扫表现为分叶状肿块,内见少量出血,边界清晰,增强后明显强化.长骨pPNETs表现为溶骨性骨质破坏伴巨大软组织肿块,无钙化,无骨膜反应.T1WI上表现为等或低信号,T2 WI上表现为不均匀高信号,增强后明显强化.脊椎pPNETs表现为椎体或附件骨质破坏伴软组织肿块,不累及椎间盘,其中1例骶骨pPNETs DSA检查示肿瘤由髂内动脉供血和大量新生血管.结论:CT和MRI均能很好地显示pPNETs的内部结构、病变范围、有无侵犯毗邻组织器官或远处转移.DSA可明确肿瘤供血动脉和反映新生肿瘤血管丰富的特点,可作为一种补充检查方法.确诊仍需依靠病理和免疫组化检查.     

Solitary fibrous tumor of the pancreas

A solitary fibrous tumor (SFT) originating in the pancreas is rare. We report a 55-year-old woman with an asymptomatic pancreatic mass incidentally discovered on abdominal ultrasonography. Contrast-enhanced computed tomography (CT) showed a well-demarcated exophytic mass in the pancreatic head with prolonged and delayed enhancement. The mass showed hypointensity on T1-weighted images and heterogeneous hypointensity with spotty hyperintensity foci on T2-weighted images. Fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT showed no significant FDG uptake. The resected mass was composed of spindle cells that were positive for CD34; and hemangiopericytomatous vessels were focally detected. The mass was finally diagnosed as an SFT of the pancreas.     

Well differentiated fetal adenocarcinoma of the lung in a 38-year-old woman: dynamic computed tomography findings

We report a case of well-differentiated fetal adenocarcinoma (WDFA) of the lung, with emphasis on dynamic CT (computed tomography) findings. The patient was a 38-year-old woman who was found to have a mass in the left upper lung field in chest radiograph screening. Chest radiograph showed a 5.5 cm well-defined mass in the left upper lung field. CT revealed a well-circumscribed mass measuring 5.5 × 5.5 × 5.0 cm with a lobulated margin in the left upper lobe. Intratumoral enhancing vasculature was noted in the early phase of dynamic CT. In the delayed phase, persistent and plateau enhancement was seen. The tumor also had consistently unenhanced areas, suggesting the presence of necrosis. Left upper lobectomy with mediastinal lymph node dissection was performed. The pathology specimen contained tubular glands consisting of non-ciliated columnar cells with areas of solid nests of epithelial cells with weakly eosinophilic cytoplasm (morule) mimicking fetal lung tissue. The tumor was moderately vascularized with areas of comedo necrosis; the stroma was relatively scanty. Final pathological diagnosis was WDFA with left hilar lymph node metastasis (stage T2bN1M0). This is the first report of dynamic CT findings of WDFA, a rare lung tumor. Although these findings are non-specific, they well reflected the pathological characteristics of this tumor.     

Solitary fibrous tumor of the male pelvis: findings at CT with histopathologic correlation

We present CT imaging findings with pathologic correlation in a rare case of a solitary fibrous tumor arising in the pelvis in a 34-year-old man. This tumor presented as a hypervascular heterogeneously enhancing deep pelvic mass at CT. Although CT initially suggested the prostate as the site of origin for this tumor, no prostate involvement was found at surgery; CT accurately excluded bladder and rectal involvement.     

Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. Received: 3 February 2000 Revised: 23 June 2000 Accepted: 22 August 2000     

Solitary fibrous tumor of the trachea: CT findings with a pathological correlation.

We present the multidetector CT findings with a pathologic correlation for the case of a solitary fibrous tumor located in the trachea. The MDCT revealed a well-circumscribed intraluminal mass arising from the trachea, with strong nodular enhancement in the periphery of the mass. The enhancement pattern of the mass corresponded histopathologically to a focal hypocellular area in the center and prominent blood vessels along the periphery of the mass. We also present volume-rendered and virtual bronchoscopic images of this rare submucosal tracheal tumor.     

胸内孤立性纤维瘤3例报告并文献复习

目的探讨胸内孤立性纤维瘤(solitary fibrous tumor,SFT)的影像学表现,提高对该病的诊断和鉴别诊断水平。资料与方法回顾性分析3例经手术病理证实的胸内SFT的临床、影像学及病理资料。3例均行螺旋CT平扫与增强扫描,其中2例行多平面重组(multi-planar reformatting,MPR),1例行MRI平扫;结合文献探讨胸内SFT的影像学表现。结果 3例胸内SFT分别位于肺内、斜裂胸膜、后胸壁脏层胸膜,肿块均为孤立肿块。1例左下叶背段外周肿块CT平扫为界限清楚软组织肿块,增强扫描动脉期肿块内见"簇"状、"线"状强化小血管影,延时扫描肿块呈非均匀强化,部分实性成分呈渐进性强化;MR T1WI上肿块呈稍短T1信号,T2WI上呈"地图"样高低混杂信号,以短T2信号为主;1例斜裂肿块平扫表现为"卵圆"形边缘光滑均质软组织密度肿块,增强扫描呈中度均匀强化;1例后胸壁脏层胸膜肿块CT平扫为非均质肿块,增强后肿块呈轻度类环状强化,内部见大片非强化坏死区,邻近见"贴边血管征"。3例均未见肺门和纵隔淋巴结肿大,手术病理结果示肿块界限清楚,有包膜或假包膜。镜下肿瘤细胞为长梭形,细胞排列成"束"状、"漩涡"状或"不规则"状,细胞密集区与疏松区交替出现,可见粗大的"瘢痕"样玻璃变性的胶原纤维相间,部分视野可见血管外皮瘤样结构,1例左下叶背段病变示陷入的细支气管及肺泡上皮。免疫组织化学检查:CD34或CD99、癌基因(Bcl-2)、波形蛋白(Vimentin)均呈强阳性。结论胸内SFT少见,其影像表现具有相对特征性,确诊需依靠病理组织学及免疫组织化学检查。     

巨块型肝细胞癌内血供的螺旋CT和超声征象的对照研究

目的对巨块型肝细胞癌内血供的螺旋CT征象和超声征象进行对照研究。资料与方法分析对照经本院手术病理证实或临床确诊的6l例原发性巨块型肝细胞癌内血供的螺旋CT和超声征象,并选取29个病理点进行影像征象与病理的点对点对照。结果（1）61例病灶中,CT显示肿瘤血管粗多者26例,其中超声显示为血供丰富者20例,较丰富者5例,稀少者1例;CT显示肿瘤血管细多者26例,其中超声显示血供丰富者13例,较丰富者9例,稀少者4例。（2）CT显示肿瘤血管粗多者26例中,超声显示19例为低回声;CT显示肿瘤血管细多者26例中,超声显示11例为高回声。结论巨块型肝细胞癌瘤内血供的螺旋CT和超声征象之间存在一定的对应关系。     

Imaging of retroperitoneal ganglioneuroma

The aim of this study was to describe the radiological appearance of retroperitoneal ganglioneuroma. We retrospectively reviewed seven cases of histologically proven retroperitoneal ganglioneuroma. Ultrasound and enhanced CT were obtained in all cases, and MRI in three cases. The masses were well-circumscribed, ranged in size from 5 x 3 x 3 to 10 x 6 x 4 cm. In three cases close relationships between the tumor mass and major blood vessels were noted, resulting in vessel displacement or surrounding, but without compression or occlusion. On ultrasound examination the tumor showed a heterogeneous solid echostructure. Non-enhanced CT showed homogeneous or mildly heterogeneous low attenuation, and a punctate calcification was seen in one case. Contrast uptake was absent (n = 1) or delayed (n = 6). Progressive but incomplete enhancement was observed in three cases. On MRI, T2-weighted images showed a high signal intensity. Dynamic studies depicted the same enhancement pattern as described on CT. Ganglioneuroma is a rare tumor which should nevertheless be included in differential diagnosis of retroperitoneal masses when presenting as a well-delimited tumor with possible tendency to surround or displace major blood vessels, low density on non-enhanced CT, and delayed progressive enhancement on CT and MRI.     

Evaluation of abdominal aortic aneurysm after endoluminal treatment: comparison of color Doppler sonography with biphasic helical CT

OBJECTIVE: The purpose of this study is to compare color Doppler sonography with biphasic helical CT in the evaluation of abdominal aortic aneurysms after endovascular repair. MATERIALS AND METHODS: Fifty-five patients prospectively underwent both color Doppler sonography and helical CT within 7 days after treatment by endovascular stent-graft. Aneurysmal thrombosis, the patency of the grafts, and the presence of a leak were evaluated in all patients. When a perigraft leak was observed, an attempt was made to identify its origin and outflow vessels. Helical CT was considered the gold standard technique. RESULTS: Helical CT revealed aneurysmal thrombosis in 33 patients and a perigraft leak in 22 patients. In five patients, helical CT detected a small perigraft leak not shown by color Doppler sonography. In three patients with suboptimal examinations, color Doppler sonography revealed a suspected perigraft leak that was not confirmed by helical CT. In these eight patients, the perigraft leak was sealed or no longer observed during follow-up. Compared with enhanced helical CT, the sensitivity and specificity of color Doppler sonography for the diagnosis of a perigraft leak were 77% and 90%, respectively. In seven other patients, helical CT was superior to color Doppler sonography in detecting the origin of the perigraft leak and the outflow vessels. Two iliac artery dissections and one distal migration of the prosthesis were revealed only by helical CT. CONCLUSION: Although color Doppler sonography may detect substantial perigraft leaks, helical CT is superior for detecting the origin of the perigraft leak, the outflow vessels, and the detection of complications related to the procedure.     

胸膜外孤立性纤维瘤CT和磁共振表现

目的探讨胸膜外孤立性纤维瘤（extrapleural solitary fibrous tumor,ESFT）的cT和MR表现。方法回顾性分析8例经病理证实的ESFT的CT和MRI表现。结果8例ESFT中,发生在眼眶和腹膜后各2例,小脑、肾脏、胰腺和食管各l例。cT或MRI表现为圆形或卵圆形肿块,4例密度或信号均匀,4例不均匀。增强后肿瘤实质区均明显强化。病理学检查肿瘤均由梭形细胞构成,免疫组织化学CD34阳性具有特征性。结论ESFT的CT和MRI表现呈多样化。增强扫描可提高诊断准确性。     

颈动脉体瘤的CT、MRI诊断

目的 分析颈动脉体瘤的CT和MRI表现.资料与方法 经手术证实的颈动脉体瘤7例,7例均行CT平扫,其中5例行CT增强扫描;3例行MRI平扫,其中2例行MRI增强扫描.结果 7例病变均为单发.7例均位于颈动脉分叉水平,颈动脉分叉扩大.CT平扫病变均呈等密度.MRI示T1WI呈等信号1例,略高信号2例,T2WI为不均匀高信号,内可见血管流空,肿瘤边缘清晰;增强后显示所有病变明显强化.结论 CT和MRI可对颈动脉体瘤作出明确诊断.     

Radiofrequency thermal ablation of hepatocellular carcinoma: using contrast-enhanced harmonic power doppler sonography to assess treatment outcome

OBJECTIVE: We evaluated the accuracy of contrast-enhanced harmonic power Doppler sonography in assessing the outcome of radiofrequency thermal ablation of hepatocellular carcinoma. SUBJECTS AND METHODS: Fifty patients with 65 hepatocellular carcinoma nodules (1-5 cm in diameter; mean diameter, 2.5 cm) were studied using unenhanced and contrast-enhanced harmonic power Doppler sonography before and after IV administration of a microbubble contrast agent. The examinations were repeated after treatment of the tumors with radiofrequency ablation. Findings of the Doppler studies were compared with those of dual-phase helical CT, which were used as points of reference for assessing treatment outcome. RESULTS: Before radiofrequency treatment, intratumoral blood flow was revealed by unenhanced power Doppler sonography in 48 (74%) of 65 hepatocellular carcinoma nodules. After injection of the contrast agent, intratumoral enhancement was observed in 61 (94%) of 65 hepatocellular carcinomas (p < 0.01). After radiofrequency treatment, all 51 (84%) of the 61 hepatocellular carcinomas found to be necrotic on helical CT scans failed to show enhancement on power Doppler sonograms. In nine of the 10 lesions that showed a residual viable tumor on helical CT scans, persistent intratumoral enhancement-matching the enhancing areas on helical CT images-was revealed by power Doppler sonography. These nine hepatocellular carcinomas were subjected to repeated radiofrequency thermal ablation with the guidance of contrast-enhanced power Doppler sonography. Complete necrosis was seen after the second treatment session in six of the nine lesions. CONCLUSION: Contrast-enhanced harmonic power Doppler sonography is an accurate technique for assessing the outcome of radiofrequency thermal ablation of hepatocellular carcinoma and may be useful in guiding additional treatment in patients with incomplete response to initial efforts.     

螺旋CT在小肾癌诊断中的价值

目的评价螺旋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,分析其螺旋CT平扫、皮质期、实质期及肾盂期的表现。结果CT平扫病灶呈等密度7例,稍低密度5例,稍高密度1例,1例为囊实性肿块,其中2例伴斑点状钙化。增强扫描皮质期12例呈明显强化,2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特征性,对小肾癌的诊断有重要价值。     

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。     

Adenocarcinoma of the head of the pancreas: determination of surgical unresectability with thin-section pancreatic-phase helical CT

OBJECTIVE: This study was conducted to evaluate newly introduced criteria for unresectability of pancreatic cancer with thin-section pancreatic-phase helical CT. MATERIALS AND METHODS: Twenty-five patients with adenocarcinoma in the head of the pancreas underwent thin-section pancreatic-phase helical CT. The major peripancreatic vessels were categorized on a scale of 1-4, according to the degree of circumferential involvement by tumor. The maximum diameters of the small peripancreatic veins--gastrocolic trunk, anterosuperior pancreaticoduodenal vein, and posterosuperior pancreaticoduodenal vein--were recorded. Findings on CT were compared with the results of surgery in each patient. RESULTS: Sixteen patients had surgically resectable tumors, and nine patients had surgically unresectable tumors. CT and surgical correlation was available for 98 major peripancreatic vessels; 85 were resectable and 13 were unresectable. Of category 1 vessels, 72 (97%) of 74 were resectable at surgery. Of category 2 vessels, 12 (71%) of 17 were resectable. One (50%) of two category 3 vessels and none (0%) of five category 4 vessels were resectable at surgery. CT showed a dilated gastrocolic trunk in two patients; one of these patients had a surgically resectable tumor, but the other patient had a surgically unresectable tumor. CONCLUSION: In patients with adenocarcinoma in the head of the pancreas, the degree of circumferential vessel involvement by tumor as shown by CT is useful in predicting which patients will have surgically unresectable tumors. A dilated gastrocolic trunk should not be used as an independent sign of surgical unresectability.     

The local spread of lower bile duct cancer: evaluation by thin-section helical CT

This study illustrates the local spread of lower bile duct cancer with thin-section helical CT in correlation with the surgical and pathological findings. Pathologically, 16 patients had pancreatic invasion, 4 had small bowel mesentery invasion, 7 had extrapancreatic nerve plexus invasion, and 3 patients had vascular invasion. On thin-section helical CT, pancreatic invasion was correlated to the clarity or non-clarity of the bile duct mass-pancreas border and the presence of an intrapancreatic mass. Cases with small bowel mesentery and extrapancreatic nerve plexus invasion showed mass or stranding around the superior mesenteric artery and/or inferior pancreatoduodenal artery. Vascular invasion was seen as tumor contiguity to these vessels. Received: 28 September 1998; Revised: 30 December 1998; Accepted: 2 April 1999     

多层螺旋CT在肾上腺巨大肿瘤手术中的价值

目的 探讨多层螺旋CT(MSCT)在肾上腺巨大肿瘤手术中的价值. 资料与方法 采用GE 64层螺旋CT机,对超声或CT平扫提示腹膜后肾上腺区域8～15 cm的巨大占位性病变的8例患者,其中男5例,女3例,平均年龄38.2岁,进行双期增强扫描,利用获得的横断影像进行影像后处理. 结果 7例增强后肿块呈不均匀强化,占位明显,与周围的结构分界清楚,并发现常伴有一支或多支起源不同的供血动脉与肿块相连.7例患者成功地实施了肿瘤切除手术,术后随访3～12月未见肿瘤复发;另1例双侧肾上腺区域巨大肿块伴腹腔淋巴结肿大的患者,选择了放疗和化疗. 结论 应用MSCT对肾上腺巨大肿瘤进行双期增强扫描及影像后处理,不仅为肾上腺巨大肿瘤的定性诊断提供了重要的信息,对肾上腺巨大肿瘤术前的评估、术中的指导及术后的评价都具有积极的作用.