CT of intrahepatic lithiasis

Twenty out of 65 patients, submitted to percutaneous treatment for intrahepatic stones at our department since 1983, had ultrasound (US) and computed tomography (CT) performed before any treatment. CT visualised stones in 65% of patients while distribution of stones was assessed correctly in 40%. In 5 patients CT provided information useful for treatment: in one case extremely dilated bile ducts hindered cholangiographic evaluation of lithiasis while in the other four cases CT examinations showed stones in dilated bile ducts unrecognised on percutaneous or endoscopic retrograde cholangiography. It is concluded that CT is a useful tool in the diagnosis of bile duct lithiasis. It aids in treatment selection and, when the percutaneous approach is chosen, allows the interventional radiologist to select the ducts to be catheterised. Correspondence to: D. ReggePresented at the ECR 91     

非增强螺旋CT低剂量扫描在泌尿系结石诊断中的可行性

目的探讨非增强螺旋CT低剂量扫描在诊断急性腰腹痛或怀疑泌尿系结石中的可行性。方法选择30例临床急性腰腹痛或怀疑患有泌尿系结石而未进行过螺旋CT扫描的患者进行常规剂量和低剂量扫描,扫描层厚10 mm,重叠重建1 mm,并进行MPR等后处理。对获得的图像进行诊断敏感性及准确性分析。结果图像经两名经验丰富的放射科医师进行了评估,所有低剂量扫描图像均获得成功。低剂量螺旋CT扫描中30例患者检出35枚结石,敏感性100%,准确性96.5%。结论研究表明,低剂量螺旋CT扫描对于泌尿系结石的诊断是安全并且敏感的,同时较常规剂量扫描明显减少了患者所接受的辐射剂量。     

Helical CT of the urinary tract

The advent of helical CT has changed the practice of uroradiology and has significantly benefited patients. Painful, obstructing ureteral stones can be diagnosed with certainty in less than 1 min without contrast medium. Radiologists can now thoroughly evaluate and characterize small renal masses without fear of skip areas caused by respiratory misregistration. Radiologic evaluation of living potential renal donors, formerly a two- or three-stage procedure, can now be performed in a single visit. Finally, three-dimensional reconstructions allow use of the same data both to diagnose tumors and to plan their resection. Axial or three-dimensional images generated using helical CT will likely be increasingly important in detecting and staging cancer, determining stone composition and appropriate therapy, and evaluating renal artery stenosis.     

ESWL治疗泌尿系结石192例报告

作者对体外冲击波碎石术（ESWL）治疗泌尿系结石192例进行了总结。认为CS-2000MP型体外冲击波碎石机由于采用B超定位，避免了X线室位对人体的损害，提高了输尿管中下段结石的碎石成功率，其操作简便，使用电压低，冲击波次数少，安全无痛苦。同时作者对影响碎石的因素和术后并发症的处理进行了探讨，对开展此项治疗技术的医院具有一定的指导意义。     

Helical CT of the urinary organs

Despite of the diagnostic potential of conventional CT (CCT), limitations being inherent in this technology reduce its diagnostic confidence and limit clinical CT applications as 3D imaging. Helical CT (HCT) has far overcome the limitations of CCT and has become the standard CT technology. After a short overview on the technique of HCT and its advantages over CCT, the impact of HCT on the detection of disorders of the urinary organs is discussed. Due to the high quality of 3D reconstructions, vessels are visualized free of artefacts resulting in a dramatic improvement and acceptance of CT angiography, which has become a clinically important examination in the evaluation of obstructive renal artery disease. Fast HCT provides a precise assessment of the three phases of the nephrogram and it is a prerequisite for an improved depiction of abnormal vascular perfusion and impaired tubule transit of contrast material. Helical CT enables an improved characterization of cystic mass lesions reducing the diagnosis of indeterminate masses and thus facilitating a better therapeutic management. The diagnosis of renal cell carcinomas (RCC) has improved due to an increased sensitivity in detecting small RCCs, and an increased specificity in the diagnosis of neoplastic lesions. Improved staging of RCCs is the result of accurate assessment of venous tumour extension. When planning nephron-sparing surgery 3D display of the renal tumour helps to determine the resectability of the mass depicting its relation to major renal vessels and the renal collecting system. In the evaluation of renal trauma HCT provides shorter scanning time and thus fewer artefacts in the examination of traumatized patients who cannot cooperate adequately. Three-dimensional postprocessing modalities allow the assessment of the renal vascular pedicel by CT angiography and improve the demonstration of complex lacerations of the renal parenchyma. In the evaluation of the upper urinary tract unenhanced HCT has become the imaging method of choice in the diagnosis and differential diagnosis of acute flank pain since it is highly sensitive and specific in detecting calculus disease. Unenhanced HCT may furthermore demonstrate causes of flank pain unrelated to urolithiasis. Gapless volume scanning and improved resolution in the z-axis during the excretory phase enables improved visualization of the renal collecting systems and ureters, resulting in a better demonstration of intraluminal and extraluminal pathology.     

急性梗阻性自发性尿外渗的CT诊断(附3例报道)

目的：探讨梗阻性自发性尿外渗的CT表现以及在临床诊断中的重要意义。方法：搜集3例急腹症患者,经临床初步诊断泌尿系梗阻或伴有肠梗阻,并行CT检查。结果：3例患者均显示患侧肾脏体积明显增大,皮质较对侧肿胀,除了肾盂、肾盏或输尿管扩张外,伴有肾周间隙、输尿管周围不规则液体密度影,增强扫描可见对比剂渗入腹腔内。结论：CT检查对急性梗阻性自发性尿外渗诊断和鉴别具有重要意义。     

CT evaluation of glucagonomas

Seven patients with clinical features of the glucagonoma syndrome, including the characteristic rash, diabetes mellitus, and weight loss, were examined by CT. Computed tomography demonstrated a primary pancreatic tumor in all patients, and, in four, hepatic metastases were identified. The primary tumors, relatively large and solid in nature, varied in size from 2.5 to 6 cm in maximum diameter. The tumor was found in the tail of the pancreas in three patients and in the head of the pancreas in four. No obliteration of adjacent perivascular or peripancreatic fat planes was observed in any patient. Calcification was present in the primary tumor in three patients and in the hepatic metastases in one. All tumors that were studied angiographically were found to be hypervascular. In contrast to insulinomas, which are frequently quite small when clinically diagnosed, glucagonomas appear to attain considerable size prior to being clinically apparent. Thus, we conclude that CT ought to become the mainstay in the identification, localization, and staging of these tumors.     

CT evaluation of chondroblastoma

Chondroblastoma is a rare benign primary bone tumor with generally characteristic plain radiographic features. In some cases, however, the benign nature and the extent of the lesion may not be appreciated using conventional radiography. We report the CT findings of chondroblastoma in three patients. In one patient CT clearly defined cortical destruction, which was not well visualized on plain radiography or conventional tomography. In a second patient CT showed a sclerotic rim absent on plain radiography; this suggested the benign nature of the lesion. Other advantages and potential pitfalls of CT in evaluating chondroblastoma are discussed.     

CT evaluation of achalasia

A retrospective review of CT scans on patients referred with either a definitive or a tentative diagnosis of achalasia was undertaken. Twelve patients were identified, of whom nine had proven achalasia. The remaining three patients were later definitively diagnosed with pseudoachalasia, benign stricture, and leiomyomatosis, respectively. Findings in all nine achalasia patients were similar: moderate to marked esophageal dilatation (mean diameter 4.35 cm at carinal level) with normal wall thickness. Findings are in distinct contrast to the three patients with other diseases, in which the degree of esophageal dilatation and/or wall thickness was atypical. Complications in the patients with proven achalasia included secondary carcinoma (one), iatrogenic esophageal perforation (one), and pulmonary aspiration (three). Computed tomography may not be indicated as a routine study, but in complicated cases CT may be invaluable in confirming the diagnosis or in detecting atypical features that may indicate the presence of other diseases or superimposed benign or malignant processes.     

三聚氰胺致泌尿系统结石的CT表现

目的 总结三聚氰胺致泌尿系统结石的CT表现.方法 同顾性分析19例有服用三聚氰胺污染奶粉史患儿的CT及B超表现.结果CT共发现双肾盂、双输尿管结石1例;一侧肾盂结石、对侧输尿管结石1例;双肾结石2例;单侧肾结石6例;双侧输尿管结石1例;单侧输尿管结石2例;肾盂扩张1例;5例未见异常.膀胱内未见结石.9例为结石合并梗阻,1例只发现尿路梗阻而无结石.CT扫描中发现最小结石为0.3 cm×0.3 cm,最大为肾盂肾盏铸型的鹿角状结石.结石中密度较低的CT值为40～70 HU,最高密度值为410 HU,平均CT值为160 HU.结论CT平扫对三聚氰胺致泌尿系统结石显示效果好,可作为B超诊断困难时的进一步枪查方法 .     

Pictorial review: CT urography and virtual endoscopy: promising imaging modalities for urinary tract evaluation

CT urography and virtual endoscopy images are generated from dedicated multislice helical CT data sets and various three-dimensional reconstruction techniques. These imaging techniques can provide external and endoscopic images of the urinary tract and also provide high spatial resolution images helping overcome some of the limitations of intravenous urography and ultrasound. This pictorial review presents clinical applications of CT urography and virtual endoscopy in various urinary tract abnormalities.     

螺旋CT诊断输尿管结石的应用价值（附32例报告）

目的评价螺旋CT对输尿管结石的诊断价值。方法对32例临床表现急性腰腹痛、镜下血尿，可疑输尿管结石的患者，行螺旋CT检查，将获得的容积图像行三维立体重建成像处理。结果31例螺旋CT图像显示出输尿管结石，确诊率97％。8例CT三维立体成像显示结石引起肾盂、输尿管扩张及结石周围组织水肿等继发性变化。结论螺旋CT诊断输尿管结石安全、快捷、准确，有较高的临床应用价值。     

Radiologic evaluation of continent urinary reservoirs

A variety of methods are currently used for urinary diversion after cystectomy in adults. Radiologists are generally familiar with ileal and colonic conduits but are less familiar with the recently popularized continent urinary reservoirs. We describe and illustrate the surgical technique, normal anatomy, and normal radiographic appearance of a variety of urinary reservoirs, including the Kock pouch, Camey procedure, and various ileocecal reservoirs. Complications of various reservoirs are also discussed and illustrated.