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Magnetic resonance imaging for paediatric retroperitoneal masses: Diagnostic accuracy of the claw sign
Background: The claw sign is advocated as a discriminant of renal versus non-renal origin of tumours. The accuracy of the claw sign on magnetic resonance imaging (MRI) is unknown and is potentially hindered by the inferior spatial resolution and the larger tumour sizes at presentation in developing countries.Objectives: To define and evaluate the claw sign in differentiating renal from non-renal retroperitoneal masses in children undergoing MRI.Methods: A definition of the claw sign was proposed. Magnetic resonance imaging studies, clinical and laboratory records of 53 children were reviewed to test the diagnostic accuracy, inter- and intra-observer reliability. Three tumour–mass interface characteristics, inherent to the claw sign, were tested: (1) a smooth tapering kidney edge blending continuously with the tumour, (2) absence of infolding of the kidney and (3) an obtuse superficial angle.Results: The sensitivity, specificity, negative predictive value and positive predictive values of the claw sign were 97%, 74%, 83% and 94%. The Cohen’s kappa values for intra-rater reliability were 0.72 (95% confidence interval 0.54–0.86) for the first reader and 0.83 (0.66–1.00) for the second reader. The Cohen’s kappa values for inter-rater reliability were 0.67 (0.50–0.85) and 0.65 (0.44–0.86) for the second reading respectively (p < 0.0001).Conclusion: The three tumour–mass interface characteristics investigated are all important characteristics of the claw sign. Intra- and inter-rater reliability is moderate to strong for all characteristics and overall impression of the claw sign. The claw sign is therefore sensitive in the accurate placement of an intra-renal mass but lacks specificity
Preliminary experience with 3T magnetic resonance elastography imaging of the liver
Background: Magnetic resonance elastography (MRE) is a promising non-invasive technique for the identification and quantification of hepatic fibrosis. This manuscript describes our early experience with MRE for the assessment of the presence and staging of liver fibrosis on a 3T magnetic resonance imaging (MRI) system.Objectives: The purpose of this study was to describe the MRE physics, procedure, interpretation and drawbacks, along with a few recommendations as per our experience.Method: Magnetic resonance elastography was performed on 85 patients with a 3T MRI and the images were analysed both qualitatively and quantitatively. Liver stiffness was assessed by drawing freehand geographic regions of interest on the elastograms to cover the maximum portion of the hepatic parenchyma within the 95% confidence maps on each slice. Correlation with histopathology was performed whenever available.Results: Of the 80 patients who met the inclusion criteria, 41 patients displayed a normal liver stiffness measurement (LSM) and 39 patients had a raised LSM. In the patients who had a raised LSM, 14 patients had Stage I–II fibrosis, 8 patients had Stage II–III fibrosis, 6 patients had Stage III–IV fibrosis, 4 patients had Stage IV fibrosis or cirrhosis and 7 patients had nonalcoholic steatohepatitis. The mean thickness of the waves increased with increasing stages of fibrosis. The waves became gradually darker medially in patients with normal LSM as compared to the patients with raised LSM. Histopathology with METAVIR scoring was available in 46 patients, which agreed with the MRE findings in all except two patients.Conclusion: Magnetic resonance elastography is a suitable non-invasive modality for the identification and quantification of hepatic fibrosis
The silent pandemic in South Africa: Extra-pulmonary tuberculosis from head to heel
Extra-pulmonary tuberculosis (EPTB), caused by Mycobacterium tuberculosis, is the leading cause of communicable disease-related deaths in people with human immunodeficiency virus (HIV) worldwide and in South Africa. Mycobacterium tuberculosis disseminates haematogenously from an active primary lung focus and may affect extra-pulmonary sites in up to 15% of patients. Extra-pulmonary TB may present with a normal chest radiograph, which often causes a significant diagnostic dilemma. This review describes the main sites of involvement in EPTB, which is illustrated by local imaging examples
Case Report : Bilateral Hutch diverticula in an elderly male: Revelation of an unknown past
Hutch diverticulum is a congenital diverticulum of the urinary bladder, reported infrequently in children and rare amongst adults. We present a 60-year-old male patient with bilateral Hutch diverticula, detected incidentally during an abdominal ultrasound examination performed for blunt abdominal trauma. This rare case highlights an unusual incidental presentation and opportunity to learn how to differentiate it from acquired bladder diverticula. The available treatment options are also discussed varying from simple follow-up to aggressive surgery
An audit of radiation doses received by paediatric patients undergoing computed tomography investigations at academic hospitals in South Africa
Background: Diagnostic reference levels (DRLs) are a crucial element of auditing radiation doses in paediatric computed tomography (CT). Currently, there are no national paediatric CT DRLs in South Africa.Objectives: The aim of this article was to establish local paediatric DRLs for CT examinations at two academic hospitals and to compare paediatric CT radiation output levels with established DRLs in the developed and developing world.Method: Computed Tomography Dose Indexvolume (CTDIvol) and dose length product (DLP) values were collected from CT examinations performed at two university hospitals for patients aged 0–15 years, during 01 November 2016–30 April 2017. The 75th percentile of the data distribution was calculated for each CT examination type and age group, further categorised into routine working hours and after-hours for both hospitals and statistically compared.Results: Of the 1031 CT examinations performed, CT brain examination was the most common (755/1031; 72.23%). DLP values were increased in the after-hours categories compared to regular working hours at both hospitals. The largest increase was in the 0–1 year age group (150.56%). With the exception of CT Chest and CT abdomen in the 0–1 year age group, the CTDIvol and DLP values compared favourably to international standards.Conclusion: Most of the calculated DRLs are acceptable and internationally comparable. This likely indicates effective reduction techniques and protocols. Computed tomography body examination protocols for 0–1 year patients should be reviewed. Strategies should be implemented to limit higher doses in after-hours examinations
A pictorial review of the pathophysiology and classification of the magnetic resonance imaging patterns of perinatal term hypoxic ischemic brain injury – What the radiologist needs to know…
This article provides a correlation of the pathophysiology and magnetic resonance imaging (MRI) patterns identified on imaging of children with hypoxic ischemic brain injury (HIBI). The purpose of this pictorial review is to empower the reading radiologist with a simplifiedclassification of the patterns of cerebral injury matched to images of patients demonstrating each subtype. A background narrative literature review was undertaken of the regional, continental and international databases looking at specific patterns of cerebral injury related to perinatal HIBI. In addition, a database of MRI studies accumulated over a decade (including a total of 314 studies) was analysed and subclassified into the various patterns of cerebral injury.Selected cases were annotated to highlight the areas involved and for ease of identification of the affected substrate in daily practice
The effectiveness of the pregnancy adapted YEARS algorithm to safely identify patients for CT pulmonary angiogram in pregnant and puerperal patients suspected of having pulmonary embolism
Background: Pulmonary thromboembolism is one of the leading causes of maternal death worldwide. Globally there has been increasing physician reliance on CT pulmonary angiogram for definitive diagnoses and exclusion of pulmonary thromboembolism. The problem, however, arises when considering the high radiation penalty from performing these investigations, highlighted by the low diagnostic yield. Of recent, the pregnancy-adapted YEARS algorithm has shown promise in international studies as a possible alternative for stratifying risk of pulmonary thromboembolism during the pregnancy and puerperal period.Objectives: To determine the effectiveness of the pregnancy adapted YEARS algorithm to safely minimise the number of true negative CT pulmonary angiograms for patients suspected of having pulmonary embolism in our clinical setting.Method: A cross-sectional study was performed in a tertiary hospital in Gauteng on puerperal and pregnant patients suspected of having pulmonary embolism. We retrospectively applied the pregnancy adapted YEARS algorithm and reviewed the various outcomes.Results: The pregnancy adapted YEARS algorithm proved effective in safely identifying patients for CT pulmonary angiography. By retrospectively applying the algorithm, there could have been a 25.7% scan reduction, whilst maintaining a negative predictive value of 100.0%.Conclusion: As physician reliance on radiological investigations increases, we must remain cognisant of the added radiation exposure and the long-term adverse effects of ionising radiation. The pregnancy-adapted YEARS algorithm provides a safe, reproducible alternative to aid our bid going forward
Cervical extension of pancreatic pseudocyst: An unusual cause of neck stiffness and dysphagia
Pancreatic pseudocyst is a common complication that can occur following acute or chronic pancreatitis. Commonly, they are peripancreatic in location. Rarely, they can extend to the mediastinum, and further extension to the neck is even rarer. A 55-year-old man who presented with neck stiffness and dysphagia and on imaging, was found to have a cystic lesion in the neck. Aspiration of the lesion revealed raised amylase levels suggestive of a pancreatic pseudocyst. 
Factor XIII deficiency in a neonate presenting as subpial haemorrhage
Subpial haemorrhage is a rare cause of seizures in term neonates. A 3-day-old male infant, born at term with no history of perinatal hypoxia, presented with seizures and unremarkable physical examination in the interictal state. Imaging demonstrated left temporal subpial haemorrhage with the classic ‘yin-yang sign’ on MRI. The patient was subsequently diagnosed with factor XIII deficiency. Follow-up at 6 months and 12 months revealed encephalomalacia in the previous haemorrhagic areas with normal developmental milestones