CT evaluation following Whipple procedure: potential pitfalls in interpretation.

A series of 41 CT examinations in 14 patients who had undergone a Whipple procedure for pancreatic cancer followed by adjuvant chemotherapy and radiation therapy were reviewed to determine the spectrum of CT findings, as well as to identify potential sources of error in interpretation. Thickening of the wall of the gastric antrum and proximal duodenum from 5 to 10 mm (9 of 14 patients) occurred as early as 1 month after completion of radiotherapy and simulated recurrent tumor. Unopacified anastomotic bowel loops in the porta hepatis in 23 of 41 examinations (56%) also mimicked recurrent tumor or adenopathy. Five of 14 patients showed liver metastases and 4 of 14 had recurrent disease in the pancreatic bed. Pneumobilia (33 of 41 examinations) was a frequent normal finding.     

CT of the abdomen after the Whipple procedure: value in depicting postoperative anatomy, surgical complications, and tumor recurrence

We performed a retrospective study of CT scans in 29 patients who had undergone the Whipple procedure (radical pancreaticoduodenectomy) to study the CT appearance of the postsurgical anatomy and assess the use of CT in the evaluation of early postoperative complications and recurrent tumor. In the postoperative period, the scans from 15 patients revealed seven transient fluid collections; four deep abscesses, three of which were successfully drained under CT guidance; three superficial abscesses; and five cases of ascites. In 19 patients, CT scans were obtained up to 4 years after surgery to search for recurrent tumor. The most frequent site of recurrence was the liver. CT correctly identified liver metastases in six of seven patients and was falsely positive in one. Recurrence also was found twice in retroperitoneal lymph nodes; one time each in the mesenteric root, spleen, and lung base; and twice causing afferent loop blockage. Surgical proof of recurrence was obtained in eight cases. Our experience suggests that an understanding of the normal postoperative anatomy following the Whipple procedure is essential in evaluating postoperative CT scans. Scans obtained for detection of tumor recurrence should be optimized for imaging the liver because this was the most frequent site of recurrence.     

Spiral CT following the Whipple procedure: distinguishing normal postoperative findings from complications

Following a Whipple procedure for a patient with pancreatic cancer, postoperative imaging with CT is essential to exclude complications and to identify recurrence. Accurate interpretation of these examinations requires knowledge of the type of surgery performed and the normal appearance of the abdomen on CT following this complex surgery. The purpose of this pictorial essay is to illustrate the normal appearance of the bowel following a Whipple procedure as well as some of the complications.     

终末期肺病肺移植术后并发症的CT表现

目的 探讨肺移植术后并发症的多层螺旋CT(MSCT)表现.方法 18例终末期肺病患者接受单肺或双肺移植,肺移植术后常规胸部MSCT平扫后,再对扫描图像进行薄层重建及多平面重建(MPR),观察移植肺实质变化的细微结构和支气管并发症等.结果 18例患者中,移植肺再灌注水肿7例,CT表现为毛玻璃片样影及胸腔积液、局限性肺实变.急性排斥反应5例,CT表现为毛玻璃片样影、小叶间隔增厚、支气管扩张伴管壁增厚、胸腔积液.慢性排斥反应1例,CT表现为毛玻璃片样影,支气管或细支气管扩张伴管壁增厚、小叶间隔增厚、胸腔积液.吻合口狭窄5例.所有患者移植后肺部均出现不同程度的感染.结论 MSCT肺部薄层重建图像可清楚显示终末期肺病肺移植术后并发症的肺内改变并准确对其评估;MSCT可作为肺移植术后定期随访复查的重要检查工具.     

Fat-filled postoperative renal cortical defects: sonographic and CT appearance

Surgical filling of renal cortical wedge resection defects with vascularized retroperitoneal fat resulted in postoperative sonographic and CT appearances that simulated focal renal masses in four patients. Correct identification of this abnormality is important in order to avoid unnecessary further evaluation to exclude renal neoplasm.     

CT appearance of appendicitis and its local complications

During evaluation for occult fever or nonspecific abdominal pain CT will occasionally identify inflammatory disease of the appendix as the underlying cause. In these cases CT may also provide useful information about the presence of associated mesenteric inflammation, abscess, or perforation. Five cases are presented in which CT provided clinically useful information supplementing that gained from barium studies and clinical presentation. When a periappendiceal lesion is found, the extent and nature of inflammatory changes are shown directly rather than inferentially.     

CT and MR of lateral disc herniation: typical appearance and pitfalls of interpretation

Lateral disc herniation is a relatively uncommon manifestation of intervertebral disc disease, defined as herniation of disc material lateral to or into the vertebral foramen. Failure to recognize this lesion preoperatively may lead to unsuccessful surgical exploration. We describe here the radiologic findings in seven patients with lateral disc herniation. Three were evaluated with magnetic resonance imaging alone, three with computed tomography alone, and one with both modalities. Example of three entities which may mimic lateral disc herniation (pseudodisc protrusion of scoliosis, paravertebral masses, and volume averaging artifacts) are illustrated.     

Sacrococcygeal chordoma: CT appearance after radiotherapy

This report presents the CT findings after radiotherapy in a case of sacrococcygeal chordoma. Observation over a long period following radiotherapy was necessary for this sacrococcygeal chordoma patient because of the slow regression of the tumor. CT was a highly effective tool in observing changes in the tumor.     

CT colonography: methods,pathology and pitfalls

Computed tomography colonography (CTC) is a relatively new technique that is currently challenging more established methods of large bowel imaging. Several workers have suggested CTC surpasses the barium enema and approaches conventional endoscopy for detection of colorectal neoplasia. Accurate diagnosis relies on technically good studies, the main aim of which is adequate bowel cleansing and distension. Furthermore, the learning curve is steep and normal colonic anatomy has to be re-learned in a CT context. This review aims to describe the technique, revise the imaging features of both normal and pathological colon, and to highlight potential diagnostic pitfalls and their avoidance.     

Pancreatic transplantation using portal venous and enteric drainage: the postoperative appearance of a new surgical procedure

PURPOSE: To review the normal radiologic appearance of pancreatic transplants that use portal venous and enteric drainage, and to review the appearance of a variety of postoperative complications. METHOD: We retrospectively reviewed the computed tomographic (CT) scans, magnetic resonance (MR) images, and ultrasounds of patients who had undergone pancreatic transplantation using portal venous and enteric drainage. RESULTS: At CT, the normal pancreatic transplant appears as a heterogeneous mass composed of pancreatic parenchyma, vessels, and omental wrap. On MR imaging, a normal transplant demonstrates intermediate signal intensity on T1- and T2-weighted sequences. Sonographic evaluation of a normal transplant reveals a hypoechoic gland that contains readily detectable low-resistance arterial and venous Doppler waveforms. Acute postoperative complications include acute rejection, which has a nonspecific radiologic appearance, and transplant pancreatitis, which is often manifested on CT by stranding of the peritransplant fat. Chronic postoperative complications include small bowel obstructions, graft pancreatitis secondary to obstruction of the Roux loop, and chronic rejection. CONCLUSION: Knowledge of the radiologic appearance of the normal pancreatic transplant is required before transplant-related complications can be detected.     

CT perfusion in acute stroke: Know the mimics,potential pitfalls,artifacts, and technical errors

The CT perfusion (CTP) imaging of brain has been established as a clinically useful tool in multimodality imaging of acute stroke. All abnormalities seen on perfusion CT are not specifically related to acute infarct. There are many neurologic diseases causing symptoms simulating cerebrovascular disease produce an alteration of brain perfusion and thus can result in perfusion CT abnormalities. There are many pitfalls and artifacts in acquiring the data, calculation of maps and choosing arterial input function. We analyze and classify all these aspects, to allow the technician and the radiologist to know exactly what to avoid and what to choose, and we indicate the way to improve the quality of examination. The knowledge of mimics and pitfalls in acute stroke imaging can be helpful in accurate interpretation of these examinations.     

CT colonography: visualization methods, interpretation, and pitfalls

Virtual colonoscopy interpretation is improving rapidly with the development of efficient software using two-dimensional, three-dimensional (3D) endoluminal, and 3D novel views such as those that seem to cut the colon open and lay it flat for interpretation. Comparison of these various views, comparisons of supine and prone positioning, and comparisons of lung and soft tissue windows aid in the recognition of various pitfalls of interpretation.