螺旋CT多期扫描在诊断小肾癌中的应用

目的：评价螺旋CT多期扫描在小肾癌诊断中的价值。方法：分析16例均经病理证实的小肾癌在平扫、皮质期、实质期及肾盂期的螺旋CT表现。结果：CT平扫中8例病灶呈稍低密度,5例为等密度,1例为稍高密度,2例为囊实性肿块。增强扫描皮质期明显强化为14例,中度强化为2例。强化为均匀或不均匀。肾实质期扫描肿瘤密度迅速减退,肾盂期扫描肿瘤密度进一步减退。结论：螺旋CT多期扫描在小肾癌的诊断中较常规CT有明显优越性;小肾癌皮质期强化明显,实质期强化迅速减退,呈“快进快退”表现,有重要的定性意义。皮质期扫描应作为小肾癌CT常规扫描。     

肾脏肿瘤的CT诊断

目的：分析肾脏良恶性肿瘤的ＣＴ表现，探讨ＣＴ对该类疾病的诊断价值。材料和方法：对手术和病理证实的１０４例肾脏肿瘤进行回顾性分析，所有病例均行平扫和增强。结果：１０４例中，良性肿瘤６例（占５．８％），均为肾血管平滑肌脂肪瘤（ＡＬＬ），ＣＴ表现为肾实质内含多种不同成分的混杂密度肿块，可有分房、分隔，内含脂肪是其特征性表现，增强后软组织部分强化，而脂肪区无强化。恶性肿瘤９８例（占９４．２％），其中肾细胞癌（ＲＣＣ）８２例，ＣＴ表现为肾实质内形态不规则、边界欠清的低密度软组织块影，动态增强后可见一过性强化。应用动态薄层增强ＣＴ扫描法准确检出小肾癌（最大径＜３ｃｍ）８例，该法为目前检查小肾癌的最佳影像方法。肾盂癌１１例（均为移行细胞癌），ＣＴ表现为肾盂内分叶状低密度软组织块影，增强后病灶强化不明显。肾母细胞瘤（Ｗｉｌｍｓ瘤）５例，均为４岁（平均２．５岁）以下小儿，ＣＴ表现为肾实质部位较大的不规则较低密度软组织块影，增强后无明显强化。结论：增强前后ＣＴ扫描对肾脏肿瘤的定位、定性诊断及术前分期均具有十分重要的价值。     

Small leiomyosarcoma of the renal capsule: CT findings

Three unusual cases of small-size leiomyosarcoma of the perirenal space were studied with CT. The renal capsule has been proved to be the origin of this type of tumor. A CT examination is accurate in suggesting the site of origin and excluding a renal cell carcinoma. However, unless evidence of invasion is noted, it is impossible on CT features to discriminate leiomyosarcoma from a benign leiomyoma. Received 11 April 1997; Revision received 2 July 1997; Accepted 4 July 1997     

MR Imaging of papillary renal neoplasms: potential application for characterization of small renal masses

The purpose of our study was to evaluate the role of MRI in demonstrating the precise nature of papillary renal tumors (P RCC) and its potential application to select patients for partial surgery. Ninety-seven tumors less than or equal to 3 cm in size [55 papillary renal cell carcinoma - 42 clear cell renal carcinoma (CC RCC)] were preoperatively evaluated by MRI. Imaging findings were assessed with a special focus on the aspect of the tumoral process. Correlations were performed with pathologic staging after surgery. At pathology, 92 tumors were established to be staged p T1 and 5 were p T3 ( 3 cases of CC RCC and 2 cases of P RCC). Ninety-four percent of papillary tumors exhibited low signal intensity with homogeneous pattern on T2-weighted images. All clear cell carcinoma were hyperintense and heterogeneous on T2-weighted sequence. Enhancement was lower and delayed in the papillary type in comparison with the clear cell type. MRI is accurate enough to predict the ‘histologic‘ nature of papillary renal carcinoma. It is an additional argument to propose that the tumor can be removed by partial surgery.     

Radiologic Findings of Renal Hemangioma: Report of Three Cases

Renal hemangioma is an uncommon benign tumor which usually causes painless or painful gross hematuria. Its preoperative diagnosis is extremely difficult or even impossible.We experienced three cases of renal hemangioma, located mainly at the pelvocalyceal junction or in the inner medulla. US demonstrated variable echogenecity, and CT revealed a lack of significant enhancement. Where there is gross hematuria in a young adult, especially when the renal mass located in the pelvocalyceal junction or inner medulla shows little enhancement on CT, renal hemangioma should form part of the differential diagnosis.     

Angiomyolipoma arising in the renal sinus: A difficult radiologic diagnosis

We report a case of angiomyolipoma (AML) occurring in the renal sinus evaluated by intravenous urography (IVU), renal ultrasound (US), angiography, and computed tomography (CT). Imaging features of this lesion are identical to AMLs elsewhere, but preoperative diagnosis was complicated by the unusual occurrence of the tumor in this location in a patient with abdominal pain. Accurate preoperative diagnosis will allow tumorectomy or conservative management.     

Primary renal carcinoid tumor: A rare cystic renal neoplasm

We present the case of a 21-year-old man with an incidentally detected cystic renal mass.A well-defined,solid mass measuring approximately 8 cm x 6 cm with a cystic component was identified in the left kidney by abdominal multidetector computed tomography(CT) and ultrasonography.The mass was well-enhanced on the corticomedullary CT phase and washout of enhancement occurred on the nephrographic phase.The mass contained peripheral wall and septal calcifications in the cystic component.The lesion was resected and diagnosed as a primary renal carcinoid tumor.Primary carcinoid tumors of the kidney are extremely rare.This case is notable because of the rarity of this neoplasm and its unique radiologic and pathologic findings.A review of previously reported cases in the literature is also presented.     

肾嗜酸细胞瘤的MRI表现

目的提高肾嗜酸性细胞腺瘤的影像诊断水平。方法回顾性分析6例经手术病理证实的肾嗜酸细胞瘤患者的MR表现。结果5例为单发肿瘤，1例并发肾透明细胞癌。肿瘤呈圆形或类圆形。直径1．5～3．8cm，境界清晰，均位于肾皮质区，向肾外突出。MR平扫，3例T1WI呈等信号，3例呈等低信号，其中1例中央可见裂隙状瘢痕更低信号；T2WI上3例呈等低信号，肿瘤内有混杂稍高信号，1例呈等稍低信号，中央瘢痕呈裂隙状高信号，2例呈低信号。动态增强扫描3例呈明显均匀强化；1例呈不均匀强化，但肿瘤实质部分强化均匀，中央瘢痕大部分延迟强化，少部分无强化；2例动脉期及静脉期扫描均呈“轮辐”状强化。结论MR检查能很好地显示肾嗜酸性细胞瘤，对临床诊断有帮助。     

MR反相位化学位移成像对肾血管肌脂瘤的诊断价值

目的:探讨MR反相位化学位移成像对肾血管肌脂瘤(AML)的诊断价值。方法:回顾性分析16例经CT证实肾AML和22例经手术证实肾癌MR反相位化学位移成像表现。结果:16例肾AML的19个肿瘤与肾实质交界面出现黑墨汁线,而22例肾癌与肾实质交界面未出现黑墨汁线。结论:肿块与肾实质交界面出现黑墨汁线提示AML,需用进一步检查来明确诊断。     

CT and US Findings of Multilocular Cystic Renal Cell Carcinoma

Objective

Multilocular cystic renal cell carcinoma (MCRCC) is a recently described variety of renal cell carcinoma with characteristic pathologic and clinical features. The purpose of this study was to analyze the imaging findings of MCRCCs.

Materials and Methods

Ten adult patients with pathologically proven unilateral MCRCC who underwent renal US and CT were included in this study. The radiologic findings were retrospectively evaluated for cystic content, wall, septum, nodularity, calcification and solid portion by three radiologists who established a consensus. Imaging and postnephrectomy pathologic findings were compared.

Results

All patients were adults (six males and four females) and their ages ranged from 33 to 68 years (mean, 46). On US and CT images, all tumors appeared as well-defined multilocular cystic masses composed of serous or complicated fluid. In all patients, unenhanced CT scans revealed hypodense cystic portions, and in four tumors, due to the presence of hemorrhage or gelatinous fluid, some hyperdense areas were also noted. In no tumor was an expansile solid nodule seen in the thin septa, and in only one was there dystrophic calcification in a septum. Small areas of solid portion constituting less than 10% of the entire lesion were found in six of the ten tumors, and these areas were slightly enhanced on enhanced CT scans. In all patients, imaging and pathologic findings correlated closely.

Conclusion

On US and CT images, MCRCC appeared as a well-defined multilocular cystic mass with serous, proteinaceous or hemorrhagic fluid, with no expansile solid nodules in the thin septa, and sometimes with small slightly enhanced solid areas. Where radiologic examinations demonstrate a cystic renal mass of this kind in adult males, MCRCC should be included in the differential diagnosis.     

Congenital ureteropelvic junction obstruction with calcified renal pelvis and superimposed spindle cell urothelial carcinoma

A case of congenital ureteropelvic junction obstruction with calcification of the walls of the renal pelvis and with a superimposed urothelial tumor is described and illustrated.     

Metastatic RCC arising in a transplant kidney

We report a case of metastatic renal cell carcinoma arising in a cadaver transplant kidney 6 years after transplantation. Due to molecular analysis of the tumor tissue we could prove that the carcinoma originated from the male donor. After tumor resection and interruption of immunotherapy, the concomitant bone and lymph node metastases resolved with alpha-interferon and interleukin-2-based immunotherapy. Received 28 August 1997; Revision received 23 December 1997; Accepted 29 December 1997     

Management of Renal Tumors by Image-Guided Radiofrequency Ablation: Experience in 105 Tumors

Aims In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors. Materials and Methods RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11–68 mm). The mean patient age was 71.7 years (range, 36–89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome. Results Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson χ²) Five patients had complications. There have been no local recurrences. Conclusion Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors.     

乏脂肪肾脏血管平滑肌脂肪瘤的MR表现

目的 探讨乏脂肪肾血管平滑肌脂肪瘤(RAML)的MR表现及不同大小RAML间影像特征是否存在差异.方法 回顾性分析2008年1月至2010年3月经手术病理证实的15例乏脂肪RAML的MR影像资料,重点分析T2WI信号强度、均匀度,是否存在假包膜,是否含有脂质,是否存在出血、坏死或囊变,是否存在血管流空影,与肾实质交界是否成角,强化是否均匀.将15例RAML根据病变最大径分为≤4 cm和＞4 cm共2组,用Fisher精确概率统计方法分析2组间影像特征的差异.结果 15个乏脂肪RAML病灶中,T2WI均表现为低信号,信号均匀者6例(6/15),出现假包膜者3例(3/15),具有脂质者4例(4/15),出现囊变者5例(5/15),有出血表现者5例(5/15),具有血管流空影者2例(2/15),病变与肾实质交界面平直,尖端成角者10例(10/15),均匀强化者8例(8/15).最大径≤4 cm者9例,最大径＞4 cm者6例.2组病变之间囊变坏死(分别为0和5例)、出血(分别为0和5例)以及假包膜征象(分别为0和3例)差异有统计学意义(P值＜0.05),而其他征象2组间差异均无统计学意义(P＞0.05).结论 乏脂肪RAML的MR影像特征主要为T2WI低信号,与肾实质交界面平直,均匀强化.病变因大小不同MR征象可以存在差异.     

肾集合管癌:螺旋CT动态增强表现

目的:探讨肾集合管癌的影像学表现及其血液动力学特征与病理的关系,以提高诊断准确性。方法:经手术病理证实的肾脏集合管癌5例,术前行CT平扫及双期(皮髄交界期和实质期)增强扫描。回顾性分析其CT表现并与手术病理结果进行对比。结果:5例肿瘤形态不规则,境界欠清,肾脏轮廓基本正常。肿瘤直径4.0~13.5cm,平均7.3cm。2例肿瘤累及皮质-髓质,3例累及肾皮质-髓质-肾盂。3例肿瘤呈实质性,内可见小区域坏死;2例肿瘤呈囊实性,内可见很不规则液性低密度区。肿瘤实质部分平扫CT值17.1~36.8HU,平均27.4HU;动态增强扫描皮髓交界期其CT值为27.4~53.5HU,平均38.7HU;实质期CT值36.0~74.2HU,平均47.6HU。1例可见斑点状和针尖状钙化。腹膜后淋巴结转移2例,肺转移1例。结论:肾集合管癌的CT表现有一定特征性,表现为肿瘤较小时位于肾髓质,较大时位于肾脏中央区,形态极不规则,境界不清,患肾轮廓基本正常;动态增强扫描示肿瘤呈中等程度渐进性延迟强化,淋巴结和远处转移常见。     

肾细胞癌的磁共振表现及病理对照研究

目的:探讨肾细胞癌(RCC)的MRI征象及其病理基础,评价其临床诊断价值。方法:41例RCC患者均行MRI平扫及增强扫描,其中10例行动态增强MRI扫描,并将MRI征象与手术病理表现对照分析。结果:肾透明细胞癌以等信号或长T1、长T2信号改变为主,颗粒细胞癌以长T1、长T2信号改变为主。MRI平扫,SE-T1WI和FSE-T2WI序列分别有21例和25例显示假包膜;对比增强扫描,38例RCC肿块明显强化,病理切片示其中34例细胞排列为实性,内含丰富的窦样血管;28例强化不均匀,病理切片示其中25例可见出血坏死;平均信号强度-时间曲线示肿瘤组织的最大强化斜率大于正常肾实质。结论:RCC的MRI表现与病理类型及肿瘤结构有关;假包膜征对诊断RCC有价值,不同MRI扫描序列和不同RCC细胞类型的假包膜征显示率无差异;动态增强MRI扫描对RCC的诊断有一定帮助。     

Renal cancer staging: Comparison of contrast-enhanced CT and gadolinium-enhanced fat-suppressed spin-echo and gradient-echo MR imaging

Fifty-three consecutive patients with 61 solid or complex non-fat-containing renal masses compatible with renal cancer were examined with contrast-enhanced computed tomography (CT) and magnetic resonance (MR) imaging with pre- and postcontrast FLASH (fast low-angle shot) and fat-suppressed spin-echo sequences. CT and MR imaging were performed within a 1-month interval. CT and MR images were prospectively interpreted. Tumor detection and staging were determined in all patients. CT and MR imaging enabled detection of 54 and 58 of 61 renal tumors, respectively. CT and MR imaging showed 34 and 35 of 38 histologically proved renal tumors, respectively, in 31 patients. Tumor size on CT and MR images demonstrated good correlation and correlated well with the size of pathologic specimens of 34 of 38 resected tumors detected with CT and MR imaging (r =.99). Of the 31 tumors in 31 patients who underwent surgical resection, 24 were correctly staged with CT and 29 with MR imaging. CT and MR imaging both enabled correct staging of four of five additional tumors with biopsy proof of tumor stage. A moderate difference in staging was observed between CT and MR imaging (P =.05). CT showed 13 and MR imaging 15 of 15 tumor thrombi. CT and MR imaging both showed 11 of 11 cases of adenopathy. The results suggest that MR imaging is moderately better than CT for the detection and staging of renal cancer.     

肾透明细胞癌CT灌注成像特点的研究

目的:探讨肾透明细胞癌灌注成像的特点及临床应用价值。方法:37例经过手术病理证实的肾透明细胞癌患者(肿瘤生长部位均靠近肾门附近),术前均选择近肾门层面进行动态增强扫描,经过灌注软件处理分析分别获得肾癌组织及双侧肾皮质的血流量(BF)、血容量(BV)、平均通过时间(MTT)、组织通透性(PS)及时间密度曲线(TDC图)。结果:肾透明细胞癌肿瘤最高密度点血供丰富,但血流量较对侧正常皮质仍较低;肿瘤平均灌注较两侧皮质均低;肿瘤同侧肾脏皮质灌注较对侧低;肿瘤内不同密度点灌注特性不同;不同分级的肿瘤对静脉血流有不同的影响。结论:肾透明细胞癌CT灌注成像具有一定的特点,对其诊断及肾血流的评估具有一定的价值。     

Intracaval extension of renal cell carcinoma

Intravenous extension occurs in many patients with renal cell carcinoma. Preoperative recognition is essential as venous involvement alters the surgical approach and clinical staging of the tumors. The venous extension of tumor has a characteristic arteriographic appearance, the recognition of which should prompt venacavography. Computerized body tomography (CBT) may also detect renal vein and caval extension and provide evidence of early ascites from the Budd Chiari syndrome associated with hepatic vein obstruction from intracaval tumor extension. However, it may be difficult to distinguish intracaval blood clot and tumor on the basis of CBT criteria alone. Of the four patients with intracaval growth of renal cell carcinoma, three received preoperative therapeutic tumor embolization, a procedure that carried no additional risk of tumor detachment and embolization.     

非对比剂增强MRA在肾静脉血管成像中的应用价值

目的:评估多反转脉冲空间标记(SLEEK)非对比剂增强磁共振血管成像(NCE-MRA)技术对显示肾脏肿瘤患者肾静脉的可行性及静脉内瘤栓的诊断效能.方法:纳入行手术治疗的肾脏肿瘤患者共32例,所有患者均知情同意,32例患者均行SLEEK序列扫描,获取双肾静脉及下腔静脉原始图像.对70支肾静脉及32支下腔静脉的原始图像、最大密度投影(MIP)图像、多平面重建图像进行评估,包括图像质量、瘤栓显示,以病理结果为金标准,评估SLEEK对瘤栓显示的准确度、敏感度及特异度.结果:非肿瘤侧肾静脉(34支)图像质量评分均在2分及以上,肿瘤侧97.2％(35/36)的肾静脉图像质量评分在2分及以上.1支肿瘤侧肾静脉显示差,不足以用于诊断,对余下肿瘤侧肾静脉及下腔静脉以病理为金标准进行评估,SLEEK显示16支肾静脉有瘤栓,14支下腔静脉有瘤栓,病理均证实;SLEEK显示无瘤栓的静脉病理中亦未发现瘤栓.SLLEK诊断准确度、敏感度及特异度均为100％.两位医师评分及诊断的一致性较好,Kappa值均＞0.75.结论:SLEEK可准确诊断肾脏肿瘤患者静脉内瘤栓存在情况,并可多角度观察瘤栓范围,从而指导临床手术方案的选择.