Two-dimensional and three-dimensional CT diagnosis of alimentary tract]

The recent development of multidetector-row CT(MDCT) has made it possible to obtain three-dimensional images of the alimentary tract that offer new diagnostic potential. In its two-dimensional diagnosis of the alimentary tract, MDCT has also changed the concept of the oral contrast agent. Before MDCT, we routinely used a positive contrast agent to distinguish the stomach and intestine from other organs and masses. The excellent slice profile acquired by MDCT can distinguish the alimentary tract and depict abnormal findings without the use of a positive contrast agent. With the use of an intravenous contrast medium, the alimentary tract itself, alimentary tumors, and inflammatory disease are well demarcated with water and air. Moreover, the combination of two-dimensional and three-dimensional diagnostic images makes it possible to detect and assess early gastric and colonic cancers as conventional gastroscopy and colonoscopy. Although the lack of texture information is one of the disadvantages of three-dimensional CT, three-dimensional CT diagnosis of the alimentary tract is less invasive and more objective than conventional studies. Advances in three-dimensional imaging with isotropic data sets will lead to the use of two-dimensional and three-dimensional CT diagnosis as one of the standard examinations of the alimentary tract.     

Cystic Lesions of the Gastrointestinal Tract: Multimodality Imaging with Pathologic Correlations

The cystic lesions of the gastrointestinal (GI) tract demonstrate the various pathologic findings. Some lesions may present a diagnostic challenge because of non-specific imaging features; however, other lesions are easily diagnosed using characteristic radiologic features and anatomic locations. Cystic masses from the GI tract can be divided into several categories: congenital lesions, neoplastic lesions (cystic neoplasms, cystic degeneration of solid neoplasms), and other miscellaneous lesions. In this pictorial review, we describe the pathologic findings of various cystic lesions of the GI tract as well as the radiologic features of GI cystic lesions from several imaging modalities including a barium study, transabdominal ultrasound (US), computed tomography (CT), and magnetic resonance (MR) imaging.     

Computerized tomography for the study of lesions of the digestive system wall

The authors investigated the role of CT in the study of intrinsic mural pathologic conditions originating from submucosal/muscular layers and of extrinsic conditions due to extraintestinal disease with secondary spread to the alimentary tract. According to the various diagnostic problems, either hypodense contrast agents (air, corn-oil emulsion, and water) or hyperdense contrast agents (iodine solutions, and barium suspensions) can be used to fill intestinal guts. Normal intestinal wall thickness does not exceed 5 mm. In case of intrinsic mural conditions, CT allows tumor extent to be evaluated, and, on the basis of densitometric values, makes the diagnosis of lipoma possible. As for intrinsic conditions (varices), CT yields specific findings. This is not the case with intestinal infarction, intramural hematoma, and phlogistic conditions, where CT generally shows aspecific parietal thickness. As for extrinsic mural conditions, CT demonstrates alimentary tract involvement due to phlogistic/neoplastic extraintestinal conditions, for it allows intestinal guts to be depicted, and the adjacent organs and structures. CT is a complementary method to conventional radiology and endoscopy which has given an excellent contribution to the study of mural pathologic conditions.     

Computed tomography of the gastrointestinal tract: lesion recognition and pitfalls.

Abnormalities in the gastrointestinal tract will be found on computed tomography (CT) scans performed for other indications if they are carefully searched for. This potential will increase as CT is used earlier in the investigation of suspected abnormalities of the pancreas. retroperitoneum, and liver. Additionally, CT may be valuable in assessing the extent of a known primary lesion of the alimentary tract.     

肝棘球蚴病破入胆系的CT诊断

目的 分析肝棘球蚴病破入胆系的CT表现，评价CT诊断的价值。方法 回顾性分析15例经手术证实的肝棘球蚴病破人胆系的CT表现：结果 15例肝棘球蚴病共有囊肿20个，其中单房单囊9个，单房多囊6个，多房多囊5个。囊壁有钙化2例；15例肝棘球蚴病均破入肝内胆管，同时破入胆总管12例，破入胆囊者2例。主要CT表现为：肝棘球蚴病合并胆系扩张。结论 CT检查能明确揭示肝棘球蚴病破入胆系的影像特点，可为术前诊断提供可靠的依据。     

小儿消化道重复畸形的临床及影像学特征分析

目的探讨小儿消化道重复畸形的临床及影像学特征。方法回顾性分析28例经手术病理证实的小儿消化道重复畸形的临床及影像学资料,术前20例行CT检查,27例行超声检查,7例行X线检查,3例行MRI检查。结果28例消化道重复畸形患儿中,位于食管3例,十二指肠2例,空肠2例,回肠14例,回盲部5例,空回肠交界处2例。术后分型为肠外型21例,肠内型4例,胸内型3例,影像学表现为多囊型3例,单囊型25例。与病理对照,CT及超声检查的诊断符合率分别为65%(13/20)和70%(19/27)。结论小儿消化道重复畸形临床及影像学特征有一定特异性,综合应用各种影像检查对提高本病的术前诊断率具有重要价值。     

CT of soft-tissue neoplasms

The computed tomographic scans (CT) of 84 patients with untreated soft-tissue neoplasms were studied, 75 with primary and nine with secondary lesions. Each scan was evaluated using several criteria: homogeneity and density, presence and type of calcification, presence of bony destruction, involvement of multiple muscle groups, definition of adjacent fat, border definition, and vessel or nerve involvement. CT demonstrated the lesion in all 84 patients and showed excellent anatomic detail in 64 of the 75 patients with primary neoplasms. CT did not differentiate vessel or nerve entrapment from neurovascular structures that were simply applied to the pseudocapsule of the tumor. Blurring of adjacent fat was an infrequent finding, but when it was present, the tumor was malignant. The CT findings were characteristic enough to suggest the histology of the neoplasm in only 13 lesions (nine lipomas, three hemangiomas, one neurofibroma). No malignant neoplasm had CT characteristics specific enough to differentiate it from any other malignant tumor. However, malignant neoplasms could be differentiated from benign neoplasms in 88% of the cases.     

肝癌的CT血管造影

目的：介绍三种螺旋ＣＴ肝脏血管造影的方法，评价其对肝癌诊断的作用。材料和方法：用三种螺旋ＣＴ肝脏血管造影的方法对４９例肝癌患者作５１次检查：肝脏动脉造影ＣＴ（ＣＴＡ）、经动脉门静脉造影ＣＴ（ＣＴＡＰ）和经术中植入门静脉的药物输入系统（ＤＤＳ）直接门静脉造影ＣＴ（ＣＴＰ）。结果：这些方法可发现直径３ｍｍ的病灶，明确显示肿瘤的血供情况。结论：ＣＴＡ，ＣＴＡＰ和ＣＴＰ有利于肝脏多发和小肿瘤病灶的检出以及其鉴别诊断，ＣＴＡ和ＣＴＡＰ虽为创伤性检查，因其敏感性很高，可在肝脏肿瘤外科手术前和需明确肿瘤的血供时选用；对植入ＤＤＳ的患者，术后复查宜常规ＣＴＰ检查。     

Computed tomography of sacral and presacral lesions

Summary Forty-two patients with various sacral and presacral lesions were examined by computed tomography (CT). CT was sensitive in detecting intraosseous neoplasms and presacral soft tissue masses and in seven cases identified lesions not visible on plain films. The total extent of each lesion was readily determined using CT. However, CT is diagnostically nonspecific and differentiation between primary and secondary tumors of the sacrum is generally not possible from the CT appearance alone. CT is also of considerable use in the evaluation of several non-neoplastic conditions of the sacrum, including spinal dysraphism, anterior and internal meningocele and trauma.     

源自消化系统黏液癌钙化性转移瘤的CT诊断

目的探讨源自消化系统黏液癌钙化性转移瘤的CT表现及诊断价值。方法回顾性分析9例经手术、病理证实为来源于消化系统黏液癌的钙化性转移瘤的CT表现。结果9例患者转移瘤内均见钙化表现,多发6例,单发3例;位于颅脑4例,位于肝脏5例。CT对钙化灶的检出率为100%。结论消化系统黏液癌易发生钙化性转移瘤,CT扫描对诊断钙化性转移瘤有重要的价值。     

Spiral-CT with multiplanar reconstructions (MPRS) in the evaluation of ureteral neoplasms: preliminary results

PURPOSE: Urothelial tumors of the upper urinary tract (renal pelvis and ureters) are rare: the most common of these are Transitional Cell Carcinomas (TCC), usually localized in the bladder (75% of cases), whereas only 7-10% arise in the renal pelvis and 2,5-5% in the ureter. Multicentricity is not infrequent and synchronous or metachronous tumors have been reported to develop in 11-13% of patients with upper urinary tract cancer and 2-4% of those with bladder cancer. The presence of additional lesions can change patient management. Clinically these tumors may present with hematuria or flank pain, but sometimes there are no specific clinical findings. Radiological studies play an important role in tumor detection and staging and in follow up. The diagnosis is usually performed by IVU and US, while CT is generally employed in the staging. Our purpose was to verify the role of Spiral CT with Multiplanar Reconstructions (MPRs) in the evaluation of ureteral tumors. MATERIAL AND METHODS: Nine patients with ureteral neoplasms were examined with a single detector spiral-CT, using the following parameters: 120 kV, 200 mA; 5 mm collimation, pitch 1.4, slice reconstruction every 5 mm; image acquisition 2-5 minutes after injection of 120 cc of contrast medium (300 mgI/ml). All the exams were transferred to a separate workstation to obtain curvilinear MPRs. RESULTS: Spiral CT on the axial plane visualized 4 urothelial tumors as concentric ureteral wall thickening; 3 as intraluminal soft tissue masses, with involvement of almost the entire urinary tract, as far as the bladder in 1 case. In other 2 patients there were synchronous lesions which presented both patterns (wall thickening and intraluminal mass). In all cases the lesions exhibited moderate enhancement after c.m. injection. Medium- to high-grade hydronephrosis above the tumors was always present. On MPRs both ureteral involvement and dilated, urine-filled upper urinary tract were clearly represented on coronal and sagittal oblique planes; these images allowed to visualize the craniocaudal extension of short or long lesions, and to detect multicentricity. DISCUSSION: The radiological diagnosis of ureteral tumors is usually performed by IVU, US and CT. IVU allows to visualize the tumors as filling defects or irregular narrowing of the ureteral lumen. IVU however is unable to show the real extent of the tumor in obstructive disease or in nonfunctioning kidney. US visualizes the lesion as an echoic mass in the lumen, although it is sometimes difficult to differentiate neoplastic lesions from other filling defects and to visualize the entire ureteral tract. CT is generally employed in the staging of ureteral tumors. CT findings are usually very useful for distinguishing ureteral neoplasms from other filling defects based on their attenuation and enhancement characteristics. Spiral CT with MPRs allows to obtain panoramic views of the urinary tract; these images are more effective than those of IVU, because of their capability to show the longitudinal extension of the lesion and the presence of multicentric tumors. Furthermore with MPRs it is possible to visualize the ureteral tract distal to the lesion, overcoming the limitations of IVU in nonfunctioning kidney or obstructive disease. CONCLUSIONS: Spiral CT with MPRs is useful in the evaluation of ureteral tumors as it is capable of visualizing the whole extension of the lesion and the presence or absence of multicentric lesions, which can change patient management.     

CT evaluation of wall thickening in the alimentary tract

Computed tomography (CT) of the alimentary tract, when performed with adequate distention of the organ being examined and in the true axial plane, provides valuable information about the intramural or extramural extent of pathologic conditions. Neoplastic, vascular, and inflammatory diseases can all result in wall thickening of the alimentary tract. Wall thicknesses greater than 5 mm in the esophagus, stomach, and colon and 4 mm or greater in the small bowel are considered abnormal. If the thickened wall has a target or double-ringed appearance, it is most likely caused by benign disease. In general, the CT findings of asymmetric or focal wall thickening, nodularity, and thickening greater than 1.5 cm suggest a malignant process. Although it is commonly associated with benign disease, diffuse thickening can also result from some infiltrating malignant diseases. Careful review of CT scans for evidence of metastatic disease and adenopathy and correlation with clinical information aid in the differential diagnosis.     

Detection of focal hepatic masses: prospective evaluation with CT, delayed CT, CT during arterial portography, and MR imaging

The sensitivities of contrast medium-enhanced computed tomography (CT), delayed CT (DCT), CT during arterial portography (CTAP), and magnetic resonance (MR) imaging for detecting focal liver lesions were prospectively evaluated in eight patients who subsequently underwent hepatic lobectomy or transplantation. Pathologic evaluation of the resected liver specimens demonstrated 37 lesions. The sensitivities were 81% (30 of 37 lesions) for CTAP, 57% (21 of 37 lesions) for MR imaging, 52% (12 of 23 lesions) for DCT, and 38% (14 of 37 lesions) for contrast-enhanced CT. The difference between the sensitivity of CTAP and the sensitivities of the other imaging tests was statistically significant (P less than .004). Of the lesions smaller than 1 cm in diameter, CTAP depicted 61% (11 of 18 lesions), MR imaging 17% (three of 18 lesions), CT 0% (zero of 18 lesions), and DCT 0% (zero of nine lesions). It is concluded that for preoperative detection of focal hepatic masses, CTAP is the most accurate technique available to most radiologists. Patients with primary or secondary hepatic neoplasms who are being considered for hepatic resection should undergo CTAP as part of their preoperative examination.     

MDCT urography of upper tract urothelial neoplasms

OBJECTIVE: The purpose of our study was to review the MDCT urography appearance of pathologically proven transitional cell carcinomas of the renal collecting system and ureter and to correlate the MDCT urography findings with pathology findings. MATERIALS AND METHODS: Of 370 MDCT urography examinations performed over an 18-month period, 18 patients were diagnosed with 27 renal collecting system or ureteral urothelial neoplasms at endoscopic biopsy (n = 8) or surgery (n = 19). Initial MDCT reports were reviewed to determine the sensitivity of original reviewers in detecting these neoplasms. Two radiologists also retrospectively reviewed these scans and characterized the CT appearance of the neoplasms on both axial CT and 3D reformatted images. Findings at retrospective review were correlated with pathology results to determine whether any CT features could be used to predict tumor grade. RESULTS: Eighteen of 27 neoplasms were prospectively identified on MDCT urography, and an additional six neoplasms were detected on retrospective review. Three ureteral neoplasms could not be visualized. The 24 retrospectively detected neoplasms had three distinct MDCT appearances: circumferential urothelial wall thickening (n = 14), small masses (> 5 mm in maximal diameter) (n = 5), and large masses (> 5 mm in maximal diameter) (n = 5). All detected lesions could be seen on axial excretory phase images provided wide window settings were reviewed; however, only six were detected on 3D reconstructions. MDCT urography appearance did not correlate with tumor grade. CONCLUSION: MDCT urography is a promising technique for detecting upper urinary tract neoplasms. The static 3D reconstructions used in this study are insufficient for visualization. Axial image review remains essential for tumor identification.     

Malignant chest wall neoplasms of bone and cartilage: a pictorial review of CT and MR findings

Malignant tumours of the chest wall are uncommon. The purpose of this pictorial essay is to describe the CT and MRI findings of malignant neoplasms affecting the bony skeleton of the chest wall and the costal cartilages. The most common primary malignant neoplasms involving the bony skeleton of the chest wall are chondrosarcoma, osteosarcoma and Ewing's sarcoma/primitive neuroectodermal tumour. Metastases, multiple myeloma and invasive primary lung cancer are the most frequent secondary lesions. We performed a retrospective review of the radiology and pathology archive at our institution from 1 July 2000 to 31 December 2004 and identified 31 of these lesions. Several of these tumours have distinctive radiological features, allowing a confident radiological diagnosis to be suggested.     

儿童三种上消化道溃疡的临床与胃镜特征

目的 探讨三种病因所致儿童上消化道溃疡临床和内镜形态特点,为儿童上消化道溃疡诊断与鉴别诊断及合理治疗提供依据.方法 对35例上消化道溃疡患儿临床资料进行总结分析,并通过胃镜检查,观察三种病因所致上消化道溃疡内镜形态特点.其中25例患儿取病变部位黏膜组织行病理检查,所有病例均进行幽门螺杆菌检测.结果 幽门螺杆菌相关性溃疡发病年龄最大,以中上腹痛为主,多伴有柏油样便,胃镜检查显示病变均在十二指肠球部,溃疡深浅不等,底部被覆白苔、黄白苔或血痂,多伴有球腔变形;腹型过敏性紫癜相关性溃疡年龄次之,多表现为全腹痛或脐周痛,可为黑便、血水样便或果酱样便,胃镜检查显示胃、十二指肠黏膜病变较弥漫,多发大小不等、深浅不一的出血、糜烂、溃疡,以十二指肠降部病变为著.非甾体抗炎药相关性溃疡发病年龄最小,均为婴幼儿,主要表现为呕吐,呕吐咖啡样物,胃镜检查显示病变均见于胃窦部,溃疡较表浅,周围黏膜充血水肿.结论 三种不同病因所致儿童上消化道溃疡临床及胃镜表现不同,据此可为儿童上消化道溃疡临床诊断、鉴别诊断及治疗提供依据.     

不同病因所致化脓性腹膜炎的CT表现特征

目的 探讨不同病因所致继发性化脓性腹膜炎(SPP)的CT表现特征。资料与方法 搜集32例有CT检查资料的SPP病例,其中经手术病理证实24例,经腹腔穿刺和／或其他临床综合指标诊断8例。着重观察引起SPP的原发病灶及腹膜炎的CT表现。结果 32例除均具有SPP的CT表现外,它们的原发病灶的CT征象显示如下：无腹部手术史的25例腹膜炎中,胃肠道穿孔10例,急性阑尾炎7例,急性胆囊炎3例,腹、盆腔脓肿3例,升结肠炎症伴周围炎症2例;有腹部手术史的7例腹膜炎中,脓肿形成5例,引起腹腔感染2例。结论 应用CT扫描诊断SPP,有利于显示SPP原发病灶及腹膜炎CT征象以及二者的解剖关联性,对临床表现不典型病例的诊断和鉴别诊断有较大价值。     

Echographic study of 116 lesions of the digestive tract

The value of US in the diagnosis of the alimentary tract diseases is discussed on the basis of a personal series of 116 cases, including 58 lesions detected by US as first investigation. The findings observed are: signet ring; pseudokidney or cockade; tram lines; solid mass; pseudokidney + solid mass. The value of the method is stressed in the staging of malignancies, in the evaluation of palpable masses, in the correct interpretation of some phlogistic diseases and in the follow up. Finally, emphasis is given to its high possibility of topographic definition. US are more and more employed in the diagnosis of abdominal diseases. Concerning the alimentary tract they still remain an investigation complementary to radiology and endoscopy. But the author's opinion is that, when employed a first investigation, one should not exclude the systematic detection of any possible unknown lesion of the alimentary tract: a good example are the 32 positive cases (24 neoplastic) in the present report.     

Computer-assisted detection of infectious lung diseases: A review

Respiratory tract infections are a leading cause of death and disability worldwide. Although radiology serves as a primary diagnostic method for assessing respiratory tract infections, visual analysis of chest radiographs and computed tomography (CT) scans is restricted by low specificity for causal infectious organisms and a limited capacity to assess severity and predict patient outcomes. These limitations suggest that computer-assisted detection (CAD) could make a valuable contribution to the management of respiratory tract infections by assisting in the early recognition of pulmonary parenchymal lesions, providing quantitative measures of disease severity and assessing the response to therapy. In this paper, we review the most common radiographic and CT features of respiratory tract infections, discuss the challenges of defining and measuring these disorders with CAD, and propose some strategies to address these challenges.     

Computed tomography and ultrasonography of carcinoma in duplication cysts

The CT and ultrasound findings of malignancy arising in walls of alimentary tract duplication cysts are previously unreported. We describe two cases where identification of both cyst and tumor nodule and separation of the mass from other visceral organs was achieved. We review the English literature reporting this unusual condition and suggest that CT and ultrasound are of great value in accurate preoperative diagnosis.