Planning and coordination of the radiological response to the coronavirus disease 2019 (COVID-19) pandemic: the Singapore experience.

Coronavirus disease 2019 (COVID-19) has spread fast and extensively around the world, with significant mortality and morbidity. As this is a respiratory infection, chest radiography and computed tomography (CT) are important imaging techniques in the work-up of this disease. Given its highly infectious nature, cross-infection within the healthcare setting and radiology departments needs to be addressed actively and prevented. We describe the response of radiology departments in Singapore to this pandemic, in terms of diagnosis, re-configuration of the department, re-organisation and segregation of staff, infection control, managerial, and leadership issues.

Emergency gastroduodenal artery embolization by sandwich technique for angiographically obvious and oblivious, endotherapy failed bleeding duodenal ulcers.

AIM: To determine the feasibility, safety, and efficacy of adopting a standardized protocol for emergency transarterial embolization (TAE) of the gastroduodenal artery (GDA) with a uniform sandwich technique in endotherapy-failed bleeding duodenal ulcers (DU). MATERIALS AND METHODS: Between December 2009 and December 2010, 15 patients with endotherapy-failed bleeding DU were underwent embolization. Irrespective of active extravasation, the segment of the GDA supplying the bleeding DU as indicated by endoscopically placed clips was embolized by a uniform sandwich technique with gelfoam between metallic coils. The clinical profile of the patients, re-bleeding, mortality rates, and response time of the intervention radiology team were recorded. The angioembolizations were reviewed for their technical success, clinical success, and complications. Mean duration of follow-up was 266.5 days. RESULTS: Active contrast-medium extravasation was seen in three patients (20%). Early re-bleeding was noted in two patients (13.33%). No patient required surgery. There was 100% technical success, while primary and secondary clinical success rates for TAE were 86.6 and 93.3%, respectively. Focal pancreatitis was the single major procedure-related complication. There was no direct bleeding-DU-related death. The response time of the IR service averaged 150 min (range 60-360 min) with mean value of 170 min. CONCLUSION: Emergency embolization of the GDA using the sandwich technique is a safe and highly effective therapeutic option for bleeding DUs refractory to endotherapy. A prompt response from the IR service can be ensured with an institutional protocol in place for such common medical emergencies.

The role of computed tomography in clinically-suspected but equivocal acute appendicitis.

INTRODUCTION: To study the role of contrast-enhanced computed tomography (CT) of the abdomen and pelvis in the evaluation of patients with clinically-suspected but equivocal acute appendicitis. METHODS: The medical records of 206 consecutive patients who had CT of the abdomen and pelvis for equivocal signs and symptoms of acute appendicitis were reviewed. 7 mm collimated axial sections from the diaphragm to the iliac crest and 5mm collimated sections of the pelvis with intravenous and oral contrast were obtained. The criteria used to diagnose acute appendicitis were: (a) a thickened appendix of more than 7 mm or (b) inflammatory changes in the periappendiceal fat. The CT findings were correlated with the histological diagnosis at appendectomy. If the CT findings were negative for acute appendicitis and surgery not performed, the results were correlated with other corroborating diagnostic investigations or clinical follow-up. RESULTS: A total of 206 patients were scanned, of which 39 were excluded due to lack of any follow-up. Of the final 167 that were studied, there were 36 true positives, 127 true negatives, 4 false negatives and no false positives, resulting in a sensitivity of 93.9 percent, specificity of 100 percent and accuracy of 98.5 percent. CONCLUSION: We have found CT to be a safe, reliable and accurate modality in the diagnosis of acute appendicitis in patients with equivocal presentation.

Current status in imaging of colorectal liver metastases.

Colorectal cancer is a common malignancy that often metastasizes to the liver. Evaluation of the liver for metastases is important for staging and prognosis. Resection of limited hepatic metastases can result in prolonged survival. Imaging is vital to select appropriate patients to avoid unnecessary surgery. A variety of modern imaging tools can be used to detect and characterise hepatic lesions. These include contrast enhanced helical computed tomography (CT), CT arterial portography, magnetic resonance imaging (MRI) and intraoperative ultrasound (IOUS). Each has their advantages as well as disadvantages. Besides accuracy, availability, cost and presence of expertise determine the optimal modality or combination of modalities to use. The appearance of metastases on imaging can be correlated with histopathological abnormalities. Though metastases can often be distinguished from benign lesions, their appearances are by no means pathognomonic. Follow-up imaging for interval change and for assessment of response is often required.

Limited magnetic resonance imaging (MRI) and the occult hip fracture.

INTRODUCTION: Diagnosis of hip fracture is normally readily made from clinical evaluation and plain radiographs. Occasionally, clinical suspicion of fracture is not confirmed on plain X-rays. MATERIALS AND METHOD: Between January 2001 and March 2002, 422 patients were admitted to our department for post-traumatic hip pain. The diagnosis of hip fracture was unequivocally made in 365 patients (86%). Fifty-seven (14%) patients had a negative or equivocal radiograph. RESULTS: Limited magnetic resonance imaging (MRI) of the hip in this group of 57 patients confirmed that 8 (14%) sustained a femoral neck fracture, while 5 (9%) had an intertrochanteric fracture. In 19 patients (33%), some other pathology was found, mainly stable fractures of the femoral trochanters and pubic rami. Overall, 32 scans (56%) were positive and 25 (44%) were negative. Limited MRI detected patients with undisplaced hip fractures and identified them as candidates for surgery. CONCLUSION: The use of MRI in this specific and 'limited' way provides orthopaedic surgeons with a rapid, accurate and cost-effective diagnostic tool in this clinical scenario. Definitive diagnosis allows the correct management plan to be implemented early. We recommend that patients, who have significant hip pain following injury but indeterminate plain radiographs, undergo a limited MRI scan as a matter of routine.

A case of right loin pain: septic ovarian vein thrombosis due to Campylobacter fetus bacteraemia.

INTRODUCTION: Septic ovarian venous thrombosis is an uncommon condition. Diagnosis is often not immediately apparent clinically and there are many that mimic this condition. We described an unusual case of septic ovarian vein thrombosis associated with Campylobacter fetus (C. fetus) bacteraemia. CLINICAL PICTURE: A 46-year-old female presented with fever and acute right loin pain. Right ovarian venous thrombosis was demonstrated on sonography and confirmed with computed tomography and magnetic resonance imaging. C. fetus was isolated from the blood. TREATMENT AND OUTCOME: The patient was given antibiotics and anticoagulation therapy with good response. CONCLUSION: Septic ovarian vein thrombosis should be considered as a differential diagnosis in female patients presenting with fever associated with lower abdominal pain. C. fetus bacteraemia also predisposes to thrombophlebitis, including septic ovarian vein thrombosis. When they are diagnosed in a timely manner and treated appropriately, the response is good and potential serious complications, including thromboembolism, and death could be averted. Radiological imaging is useful in the diagnostic work-up of this condition.

Computed tomographic appearance of colorectal hepatic metastases.

INTRODUCTION: This article reviews the various computed tomography (CT) appearances of hepatic metastases from colorectal primaries and assesses the frequency of occurrence of the various patterns. MATERIALS AND METHODS: This is a retrospective study of the CT appearances of histologically proven colorectal hepatic metastases in a group of 52 patients who had undergone surgical hepatic resection between January 1994 and December 2001. A total of 74 hepatic metastatic lesions were reviewed. All lesions were examined in the portal venous phase. RESULTS: A discernible rim was seen in 54 lesions (73%). Thick rim was present in 36 lesions (48.6%) and thin rim in 18 lesions (24.3%). Enhancement of the rim was present in 62 cases (83.8%). Increased central attenuation was seen in 38 lesions (51.4%). Of these, the centre was heterogeneous in 76.3% and scar-like in 23.7%. A non-enhancing rim was seen in 12 lesions (16.2%) which appeared as lesions with "bevelled edge". Thick enhancing rim with non-enhancing centre was the most common combination in 15 lesions (20.3%). CONCLUSION: An enhancing rim could be seen in 83.8% of lesions. Increased central attenuation was present in 51.4% of the lesions. Familiarity with the various CT appearances may facilitate identification and diagnosis of colorectal liver metastases.

Endovascular treatment of isolated systemic arterial supply to normal lung with coil and glue embolisation.

Surgery is the standard treatment for the extremely rare pathology of isolated anomalous systemic arterial supply to normal lung (ISSNL). We describe our experience with this anomaly in a 29-year-old male presenting with recurrent haemoptysis that was successfully treated with a combination of metallic coils and cyanoacrylate glue. In addition to contributing to the extremely limited data on endovascular therapeutic options in ISSNL, we also intend to raise the awareness among endovascular therapists of the need to be cautious ofand preserve the radiculomedullary/pial branches arising from an anomalous artery before embolising it.

Spectrum of imaging findings in melioidosis.

This pictorial review aims to highlight the clinical and imaging features of melioidosis in various organ systems. The patients were from two centres: one in Thailand and one in Singapore. The annual average incidence of melioidosis is estimated to be 4.4 in 100 000 in north-eastern Thailand and 1.7 in 100 000 in Singapore. Melioidosis affects many different organs and produces a spectrum of imaging features. The lung is the most frequently involved organ and, on radiographs and computed tomography, melioidosis may manifest as acute pulmonary consolidation, multiple nodules and abscesses. The finding of multiple small discrete abscesses in both the liver and the spleen is highly suggestive of visceral melioidosis and is best diagnosed on ultrasonography and computed tomography. Bone and soft tissue musculoskeletal involvement is usually part of disseminated melioidosis, with changes being seen on radiographs and MRI. Although imaging findings of melioidosis are not specific, this infection requires a high index of clinical suspicion, particularly in patients with pre-disposing comorbidities, such as diabetes mellitus, chronic renal failure, alcoholism or malignancy, those who are immunosuppressed as the result of either diseases or drug treatment, and those living in or with a history of travel to endemic areas.