M.P. Williams

Imaging the pericardium: appearances on ECG-gated 64-detector row cardiac computed tomography

Multidetector row computed tomography (MDCT) with its high spatial and temporal resolution has now become an established and complementary method for cardiac imaging. It can now be used reliably to exclude significant coronary artery disease and delineate complex coronary artery anomalies, and has become a valuable problem-solving tool. Our experience with MDCT imaging suggests that it is clinically useful for imaging the pericardium. It is important to be aware of the normal anatomy of the pericardium and not mistake normal variations for pathology. The pericardial recesses are visible in up to 44% of non-electrocardiogram (ECG)-gated MDCT images. Abnormalities of the pericardium can now be identified with increasing certainty on 64-detector row CT; they may be the key to diagnosis and therefore must not be overlooked. This educational review of the pericardium will cover different imaging techniques, with a significant emphasis on MDCT. We have a large research and clinical experience of ECG-gated cardiac CT and will demonstrate examples of pericardial recesses, their variations and a wide variety of pericardial abnormalities and systemic conditions affecting the pericardium. We give a brief relevant background of the conditions and reinforce the key imaging features. We aim to provide a pictorial demonstration of the wide variety of abnormalities of the pericardium and the pitfalls in the diagnosis of pericardial disease.

Atypical patterns in the CT diagnosis of aortic dissection

Eight cases of aortic dissection with atypical CT appearances are described. Seven were clinical diagnoses, one was confirmed at operation. The findings were those of intramural haematoma, often crescentic and not necessarily compressing the aortic lumen. Evidence is presented to show that some intramural haematomas may subsequently develop ulceration, resulting in the appearances described in penetrating atheromatous ulcer of the aorta.

Congenital anomalies of the portal venous system-CT appearances with embryological considerations

The portal vein is formed by the union of the splenic and superior mesenteric veins behind the neck of the pancreas. This system is derived from the vitelline veins, a component of the extraembryonic venous system. In this paper we report three cases, each of which illustrates a congenital variant of the portal venous system, describe their computed tomography appearances and discuss the embryological processes accounting for these anomalies.

UK Management Practices in Stage I Seminoma and the Medical Research Council Trial of Imaging and Schedule in Seminoma Testis Managed with Surveillance

Stage I seminoma accounts for 40e45% of testicular cancers [1,2], 800e900 UK cases annually [3]. After orchidectomy, care includes one of three main options: adjuvant chemotherapy (one to two cycles of carboplatin), para-aortic radiotherapy or, as more than 80% of patients are cured by surgery [4,5], surveillance incorporating regular imaging. Relapse rates after adjuvant therapy are about 4e5% [6]. However, salvage therapy is highly effective and causespecific survival approaches 100%, irrespective of initial management [7]. Given such excellent prospects, and the young age of patients, long-term implications and risks must be considered. Avoidance of treatment side-effects through the use of surveillance may be a sensible and safe approach. Here we consider current evidence regarding the efficacy and potential risks of these management options. Based on surveys of UK oncologists treating testis cancer patients in 2005 and 2009,we assess currentmanagement practices and trends over time. We highlight the limitations of evidence relating to optimal surveillance strategies and the resultant variation in practice. Finally, we introduce an ongoing Medical Research Council (MRC) randomised controlled trial (RCT), the Trial of Imaging and Schedule in Seminoma Testis (TRISST), designed to address knowledge gaps and pave the way for a standardised approach.

Lipomata of the inferior vena cava: A normal variant?

Recently, focal fat collections adjacent to the intrahepatic portion of the inferior vena cava (IVC) have been described as a normal variant. We present seven similar cases, and demonstrate the computed tomographic and sonographic findings. The differential diagnosis is discussed. We believe that the origin of these masses has not yet been satisfactorily proven, and that they may arise within the IVC. They appear to be benign, but there is a risk that they may be mistaken for more sinister pathology.

Practical applications of digital tomosynthesis of the chest

Digital tomosynthesis is a radiographic technique that generates a number of coronal raw images of a patient from a single pass of the x-ray tube. Tomosynthesis provides some of the tomographic benefits of computed tomography (CT), but at a much lower dose of radiation and cost when compared to CT. This review illustrates the range of practical applications of digital tomosynthesis of the chest.

Computed tomography in testicular tumours.

Although rare, testicular tumours have doubled in incidence over the last 15 years [1] and are the commonest cancer affecting men between the ages of 20 and 40 years. Over the last few years treatment has advanced rapidly and the overall cure rate now exceeds 90% [2,3]. Intensive treatment is required. Response is largely monitored by the serum tumour markers 0~-foetoprotein and the [3-subunit of human chorionic gonadotrophin [4], but computed tomography plays an important role. The majority of testicular tumours are of germ cell origin and are classified as either seminomas or non-seminomatous tumours (known in the UK as testicular teratomas). Testicular turnouts arising from non-germ cells (e.g. Leydig and Sertoli cell tumours) are much rarer and will not be considered further.

MDCT of retractor-related hepatic injury following laparoscopic surgery: Appearances, incidence, and follow-up

AIMS To investigate the postoperative computed tomography (CT) features resulting from the use of Nathanson retractors during laparoscopic upper gastro-intestinal surgery. MATERIALS AND METHODS A 3-year retrospective study of 176 patients who had undergone laparoscopic upper gastro-intestinal surgery for bariatric or malignant disease was performed. Postoperative CT images [divided into early (≤ 30 days) and late (>30 days)] were assessed by a consultant radiologist and liver abnormalities recorded. RESULTS The features of a retractor injury were a hypodense lesion, abutting the liver edge, usually triangular or linear in shape. Late postoperative features included focal subcapsular retraction and associated liver atrophy. Sixty-eight percent (52/77) of patients undergoing surgery for malignancy underwent postoperative CT, compared with 11% (11/99) of those undergoing bariatric surgery. Patients with malignancy were more likely to have retraction-related liver abnormalities (14/52, 27%) at postoperative CT than those in the bariatric group (2/11, 18%). CONCLUSION Retractor-related liver injuries at MDCT are common following laparoscopic upper gastro-intestinal surgery. Recognition of the characteristic triad of features, a hypodense lesion abutting the liver edge with a triangular or linear shape, should allow confident diagnosis. CT follow-up reveals that over time these lesions may disappear, remain unchanged, or result in a focal subcapsular scar with associated atrophy.

The radiological appearances of small cell (oat cell) carcinoma of the oesophagus

We present three patients with primary small cell (oat cell) carcinoma of the oesophagus from a clinical and radiological point of view and review the radiological appearances of previously reported cases. The features of this rate neoplasm are variable, but extensive circumferential oesophageal wall thickening associated with luminal widening should raise the possibility of this diagnosis.

Hydronephrosis: A rare late complication of barium enema

An 82.year-old woman presented with a 6-week history of dysuria, frequency, nausea and left flank pain. She was treated with antibiotics for a urinary tract infection with no improvement in symptoms and was referred for an ultrasound scan which showed a left sided hydronephrosis. The level of obstruction could not be demonstrated on ultrasound and so computed tomography (CT) was performed to determine the cause and level of obstntction. An unexpected finding on the scanogram was an amorphous mass of contrast medium within the left-hand side of the pelvis and ‘tramline’ calcification along the line of the left ureter (Fig. 1). Sequential axial sections confirmed left hydronephrosis and a dilated ureter with high density material within its walls (Fig. 2). The ureter continued distally into a large extra peritoneal collection of contrast medium (Fig. 3). Access to the old case notes revealed the contrast medium to be barium from a rectal perforation which had occurred during a DCBE examination 15 years earlier. This had been treated with a defunctioning colostomy, which was reversed 6 months later.