Postoperative omental infarction following colonic resection.

AIM: To illustrate the computed tomography (CT) appearances and natural history of postoperative omental infarction following colonic resection and to highlight the important clinical implications of this radiological diagnosis. MATERIALS AND METHODS: Over a 3 year period, 15 patients with a history of colonic resection were identified as having a CT diagnosis of postoperative omental infarction. Relevant clinical and pathological data were retrospectively collected from the institution's electronic patient records system and all relevant imaging was reviewed, including serial CT images in 10 patients. RESULTS: A diagnosis of postoperative omental infarction was made in symptomatic and asymptomatic patients who had undergone open or laparoscopic colonic resection for benign or malignant disease. CT appearances ranged from diffuse omental stranding to discrete masses, which typically appeared within weeks of surgery and could persist for years. In four (36%) of the patients with colorectal cancer, the CT appearances raised concern for recurrent malignancy, but percutaneous biopsy and/or serial CT allowed a confident diagnosis of omental infarction to be made. Although most cases were self-limiting, three (20%) cases were complicated by secondary infection and required radiological or surgical intervention. CONCLUSION: Postoperative omental infarction is an under-recognized complication of colonic resection. It has the potential to mimic recurrent malignancy and may require radiological or surgical intervention for secondary infection.

Provisional reporting of polytrauma CT by on-call radiology registrars. Is it safe?

AIM: To assess the accuracy of provisional reporting and the impact on patient management. MATERIALS AND METHODS: Over a 6 month period, 137 polytrauma computed tomography (CT) examinations were performed by on-call registrar radiologists at our institution. After exclusions, 130 cases were analysed. Discrepancies between registrar and consultant reports were reviewed and classified as either major or minor dependent on potential impact on patient safety. The relationship between seniority of reporting registrar and likelihood of a missed finding was analysed using the Chi-square test. RESULTS: Of the 130 patients, 46 (35%) had a serious injury, 36 (28%) a minor injury, and 48 (38%) no identifiable injury on CT. There were 32 (25%) patients with discrepancies of which 24 (18%) had missed or significantly under-reported findings and eight (6%) overcalled findings. There were six misses classified as major; the remaining 18 were classified as minor. No association was found between the seniority of reporting registrar and the likelihood of a miss (p=0.96). CONCLUSION: The incidence of major discrepancies between the provisional and final report was low and did not lead to any significant clinical deterioration. Our study provides a reference of the commonly missed injuries. We conclude that registrar provisional reporting of polytrauma is safe; however, note that a large proportion of examinations are normal and that further work is required to produce robust criteria given the radiation risk to a young population group scanned in trauma.

Composite abdominosacral resection for recurrent rectal cancer.

BACKGROUND: En bloc resection of the tumour and adjacent involved organs offers the only realistic curative option for patients with locally recurrent rectal cancer. This study assessed outcomes of composite resection for recurrent tumours involving the sacrum. METHODS: A consecutive series of patients underwent composite abdominosacral resection (abdominal mobilization and stoma construction followed by sacral division and tumour retrieval) for recurrent rectal cancer between 2001 and 2007. Patients were staged with preoperative computed tomography, magnetic resonance imaging and positron emission tomography. Data were collected prospectively. RESULTS: Forty patients (28 men; median age 59 (range 31-77) years) underwent surgery with sacral division at the S2/3 interface in 13, S3/4 level in 20 and S4/5 level in seven patients. One patient died and 24 had complications. An R0 resection was achieved in 20 patients and conferred benefit in disease-free interval over an R1 resection. The mean disease-free interval was 55.6 (95 per cent confidence interval (c.i.) 40.0 to 71.3) months for R0 and 32.2 (95 per cent c.i. 19.7 to 44.7) months for R1 resection (P = 0.048). CONCLUSION: Composite abdominosacral resection of locally recurrent rectal cancer is an effective treatment for a difficult clinical scenario.

Pre-operative MR assessment of recurrent rectal cancer.

The potential for curative resection of recurrent rectal cancer and the recognized benefits of palliative resection have led to increased numbers of patients being referred for MRI assessment. This study assesses the use of MRI to provide a roadmap of tumour recurrence to allow for appropriate surgical planning. Differentiation of recurrent rectal cancer from post-surgical and post-radiotherapy changes on MR proved particularly problematic when assessing the pelvic sidewalls. Areas of uncertainty on imaging, therefore, need to be discussed on a case by case basis regarding the decision to proceed to curative or explorative surgery.

Algorithms for the surgical management of retrorectal tumours.

BACKGROUND: Retrorectal tumours are uncommon and may present a surgical challenge. The aim of this study was to identify a surgical strategy based on information gained from the multidisciplinary management of retrorectal tumours. METHODS: This was a retrospective review of 27 patients who had resection of retrorectal tumours between 1998 and 2006. RESULTS: The tumours included ten cystic lesions, two mature teratomas, four chordomas, seven neurogenic tumours, two sarcomas, one angiomyxoma and one gastrointestinal stromal tumour. The diagnosis was suggested initially by non-specific clinical presentation and palpation of a retrorectal mass on examination (16 patients), pelvic imaging (six), obstructed labour (one), recurrent pilonidal sinus (one), recurrent perianal sepsis (one) and return of symptoms after resection (two). Magnetic resonance imaging (MRI) confirmed the diagnosis and enabled surgical planning. The operative approach was perineal (12 patients), abdominal (11) or combined (four). Factors that influenced the operative approach were tumour position, its neoplastic nature, involvement of the pelvic sidewall or pelvic viscera, and size. The retrorectal tumour recurred in three patients. CONCLUSION: A successful multidisciplinary surgical strategy, based on preoperative localization by MRI, has been developed for the treatment of retrorectal tumours.

An unusual case of ureteric obstruction.

We report a case of a 33-year-old female presenting with right sided abdominal pain, a right iliac fossa mass and right hydronephrosis. The mass was subsequently shown to represent an isolated desmoid tumour compromising the adjacent ureter. The patient had no predisposing factors for this pathology. This is an uncommon occurrence and we discuss the imaging features and differential diagnosis.

MRI assessment of the bony pelvis may help predict resectability of rectal cancer.

OBJECTIVE: The outcome after surgical treatment of rectal cancer may be influenced by the technical difficulty of the operation, which is thought to be affected by pelvic size. The aim of this study was to examine the association between bony pelvic dimensions and CRM involvement. PATIENTS AND METHODS: All patients with primary rectal cancer between December 1999 and January 2002 were studied. Staging was performed by pelvic MRI. Nine pelvic dimensions were measured from the MR images on a workstation. Pathology reports were obtained for all patients and the mesorectal specimen was examined. Technical difficulty was assessed by circumferential resection margin (CRM) involvement. RESULTS: Of 126 patients with primary rectal cancer, 88 had staging MRI and rectal excision; there were significant differences between the sexes in all 9 pelvic dimensions (P < 0.05). In females, the interspinous diameter was significantly shorter in patients with CRM involvement compared with patients with a negative CRM. In female patients predicted to have a negative CRM, the anteroposterior diameter of the inlet, the anteroposterior diameter of the midplane and the transverse diameter of the midplane (interspinous distance) were significantly shorter in patients who actually had a positive CRM compared with those in whom the CRM was negative. In male patients, there was no correlation between pelvic dimensions and CRM status. CONCLUSIONS: In certain patients with rectal cancer, CRM positivity may be predicted from pre-operative MRI pelvic measurements. This may influence the choice of adjuvant therapy.

Evaluation of the role of pre-operative magnetic resonance imaging in the management of rectal cancer.

OBJECTIVES: This study assesses the ability of body coil magnetic resonance imaging (MRI) to pre-operatively stage mural penetration, nodal status and circumferential resection margin (CRM) involvement of rectal cancer. PATIENTS AND METHODS: Between 1995 and 1997, MRI using a body coil was performed in consecutive patients with primary rectal carcinomas. Group A: 67 patients underwent surgery without long course neo-adjuvant therapy. Predicted tumour stage was compared to the histology of the specimen. Group B: 21 patients with MRI evidence of advanced disease, underwent long course neo-adjuvant therapy followed by repeat MRI prior to surgery. The second scan assessed response to treatment and likelihood of CRM involvement at subsequent surgery. RESULTS: Group A: Accuracy of pre-operative staging was: 'T' stage - 54%, 'N' stage - 77%, involvement of CRM by tumour - 97%. Group B: After long course neo-adjuvant therapy the second MRI scan was 95% accurate in predicting CRM involvement by tumour. CONCLUSION: In this study pre-operative rectal cancer staging with MRI and a body coil lacks accuracy in predicting mural penetration and nodal involvement. Body coil MRI can accurately predict the potential for CRM involvement. This technique may help determine which patients require long course neo-adjuvant therapy.

Renal metastases from a squamous cell carcinoma of the larynx.

Laryngeal squamous cell carcinoma (SCC) tends to exhibit local spread with a low incidence of distal metastases. The majority of distal metastases are to the lungs and renal involvement is extremely rare. We present a case of laryngeal SCC with metastatic spread to the left kidney presenting as a large, mainly cystic mass. The radiological differentiation of renal metastases from primary renal tumours is discussed.

Breast metastasis from non-small cell lung cancer.

Breast is an unusual site for metastatic disease, particularly for non-small cell lung cancer. We report an unusual case of metastatic breast lesions from a primary anaplastic lung tumor and discuss the common and uncommon sites of metastasis from lung carcinomas.

Imaging appearances of ileouterine fistula complicating recurrent adenocarcinoma of the rectum.

Enterouterine fistulae are rare and nowadays are most commonly due to pelvic tumours. We review the literature and present the case of a woman who presented with an ileouterine fistula following surgery and radiotherapy for recurrent rectal adenocarcinoma. The presence of tumour within the fistula track may also have been a significant aetiological factor. Magnetic resonance imaging (MRI) is an excellent method to demonstrate the site and size of the track and has not, to date, been used to identify such a fistula.

T2-weighted and dynamic enhanced MRI in acute pancreatitis: comparison with contrast enhanced CT.

The purpose of this study was to compare T2-weighted and dynamic contrast enhanced MRI with contrast enhanced CT in patients with severe acute pancreatitis. Thirty-two patients were examined using axial T2-weighted spin-echo imaging (TR 1801, TE 15/90) and a multi-slice rapid gradient-echo sequence (TR 135, TE 4, FA 80 degrees) (FLASH) in axial and coronal planes. Fifteen 5 mm axial slices at 10 mm intervals were acquired during a single breath-hold of 19 s before, and at 10 and 40 s after a bolus injection of Gd-DTPA. Additional FLASH images in the coronal plane were obtained 2 min after injection of contrast medium. MR was compared with contemporary enhanced CT by two blinded observers who scored pancreatic viability and the content of intra and extra-pancreatic fluid collections. The presence of gas, calcification and haemorrhage was noted. Abnormalities in adjacent organs, evidence of vascular occlusion and indicators of aetiology were also recorded. MR and CT were concordant in distinguishing viable pancreatic tissue from areas of necrosis. MR appeared to be more effective than CT in characterizing the content of fluid collections and in demonstrating gall stones, although CT remains superior in detecting flecks of gas and calcification. MR carries some advantages over CT and can be regarded as an alternative primary technique in patients with severe pancreatitis.

The role of imaging in acute pancreatitis.

The roles of ultrasound, computed tomography and magnetic resonance in the evaluation and management of acute pancreatitis are discussed with emphasis on the advantages and disadvantages of each. The importance of imaging in the diagnosis of pancreatic necrosis, acute fluid collections, pancreatic abscess, pseudocysts and vascular complications is reviewed. The use of interventional techniques as opposed to surgical intervention is discussed.

Spiral computed tomography and operative staging of gastric carcinoma: a comparison with histopathological staging.

BACKGROUND: Much controversy exists as to the value of computed tomography (CT) in the preoperative staging of gastric cancer, because of its limited ability to identify correctly lymph node (LN) metastases, invasion of adjacent organs, or hepatic and peritoneal metastases. Spiral CT scanners have a number of potential advantages over conventional scanners, including the absence of respiratory misregistration, image reconstruction smaller than scan collimation permitting overlapping slices and optimisation of intravenous contrast enhancement. AIM: To compare the performance of spiral CT and operative assessment against formal (TNM) pathological staging. PATIENTS AND METHODS: A study of 105 consecutive patients who underwent both spiral CT and operative staging was performed. All CT scans were reviewed by a radiologist who commented on tumour location and size, evidence of adjacent organ invasion, lymph node metastases to both N1 and N2 nodes, and evidence of hepatic and peritoneal metastases. All patients underwent careful operative assessment at the time of surgery, along the lines suggested by Rohde and colleagues. RESULTS: Spiral CT remained poor at identifying LN metastases to both N1 and N2 lymph nodes, with sensitivity ranging from 24 to 43%; specificity, however, was 100%. Operative staging was superior, with sensitivities between 84 and 94%, but specificity was much lower (63-74%). Spiral CT correctly detected 13 of 17 cases of invasion of either the colon or the mesocolon (sensitivity 76%) compared with 16 of 17 cases at operative staging (sensitivity 94%). Spiral CT correctly identified three of six cases with invasion of the pancreas (sensitivity 50%) compared with six of six cases on operative staging (sensitivity 100%). Spiral CT correctly identified 12 of 17 cases of peritoneal metastases (sensitivity 71%) and four of seven cases of hepatic metastases (sensitivity 57%). CONCLUSION: Whilst spiral CT remains poor at identifying lymph node metastases, it correctly identified most cases with invasion of either the colon or the mesocolon and half the cases of pancreatic invasion. It was of value in detecting peritoneal metastases and some cases with hepatic metastases. At present, at Leeds General Infirmary spiral CT is performed routinely on all patients with gastric cancer and a selective staging laparoscopy policy is adopted in those patients in whom the status of the peritoneal cavity and liver is in doubt.

Pseudothrombosis of the infra-renal inferior vena cava during helical CT.

Pseudothrombosis of the infra-renal vena cava is a frequent finding during post-contrast helical computed tomography (CT) studies of the abdomen. Three hundred consecutive patients undergoing contrast-enhanced helical studies were evaluated prospectively to document the incidence of pseudothrombosis. Typical CT findings are illustrated and a significant difference in incidence between the male and female population noted.