Meckel's Diverticulum - Clinical Presentation and Pitfalls in Diagnosis in the Pediatric Age Group in Singapore.

Purpose: The purpose of this study was to study the presentation of patients who underwent Meckel's diverticulectomy (MD) and utility of pertechnetate Meckel's scan in the diagnosis of MD. Methods: The clinical presentation of a retrospective cohort of patients who underwent MD from January 2007 to December 2019 was studied. The modes of presentation, treatment, and the diagnostic utility of pertechnetate Meckel's scans were evaluated. False-positive and false-negative scans were reviewed. The presence of gastric mucosa on histology of Meckel's was correlated with presentation as gastrointestinal bleeding and positive scan results. Results: Ninety-nine patients underwent MD. Thirty-five out of 263 (13.3%) Meckel's scans done were positive. There was a male preponderance (86.9%). The peak age of presentation was 0-4 years (rectal bleeding or intestinal obstruction). Only a third of the patients with Meckel's diverticulum Meckel's had a preoperative diagnosis of Meckel's. The sensitivity/specificity of Meckel's scan was higher in patients presenting with painless rectal bleeding. Seven patients were false positive (weak tracer uptake or ectopic uptake) and five were false negative. Two patients with false-negative Meckel's scan, having gastrointestinal bleeding had gastric mucosa on histology of Meckel's. Conclusion: Meckel's diverticulum has a male predominance. Meckel's scan has a high sensitivity in the children presenting with fresh painless rectal bleeding but is of limited use in the diagnosis of Meckel's diverticulum in other forms of presentations. False-positive scans can be anticipated in the presence of weak or ectopic uptake. False-negative scans can occur even in the presence of bleeding and in spite of the presence of gastric mucosa in the Meckel's diverticulum. Laparoscopy is a useful tool in diagnosis and treatment.

Pleomorphic xanthoastrocytoma with NTRK fusion presenting as spontaneous intracranial hemorrhage-case report and literature review.

Background: Pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor that accounts for <1% of all gliomas. An in-depth understanding of PXA's molecular makeup remains a work in progress due to its limited numbers globally. Separately, spontaneous intracranial hemorrhage (pICH) is an uncommon but potentially devastating emergency in young children, often caused by vascular malformations or underlying hematological conditions. We describe an interesting case of a toddler who presented with pICH, later found to have a PXA as the underlying cause of hemorrhage. Further molecular interrogation of the tumor revealed a neurotrophic tyrosine receptor kinase (NTRK) gene fusion and CDKN2A deletion more commonly seen in infantile high-grade gliomas. The unusual clinicopathological features of this case are discussed in corroboration with published literature. Case presentation: A previously well 2-year-old male presented with acute drowsiness and symptoms of increased intracranial pressure secondary to a large right frontoparietal intracerebral hematoma. He underwent an emergency craniotomy and partial evacuation of the hematoma for lifesaving measures. Follow-up neuroimaging reported a likely right intra-axial tumor with hemorrhagic components. Histology confirmed the tumor to be a PXA (WHO 2). Additional molecular investigations showed it was negative for BRAFV600E mutation but was positive for CDKN2A homozygous deletion and a unique neurotrophic tyrosine receptor kinase (NTRK) gene fusion. The patient subsequently underwent second-stage surgery to proceed with maximal safe resection of the remnant tumor, followed by the commencement of adjuvant chemotherapy. Conclusion: To date, there are very few pediatric cases of PXA that present with spontaneous pICH and whose tumors have undergone thorough molecular testing. Our patient's journey highlights the role of a dedicated multidisciplinary neuro-oncology team to guide optimal treatment.

Incidence of intussusception in Singaporean children aged less than 2 years: a hospital-based prospective study.

BACKGROUND: Continuous surveillance for intussusception (IS) is important for monitoring the safety of second-generation rotavirus vaccines. The present study aimed to assess the incidence of IS in Singaporean children aged < 2 years. METHODS: This was a prospective, hospital-based, multi-center surveillance conducted in seven hospitals - two public hospitals and five private medical centers between May 2002 and June 2010 in Singapore. Diagnosis of IS (definite, probable, possible, suspected) was based on the case definition developed by the Brighton Collaboration. Children < 2 years of age who were diagnosed with IS were enrolled in this study. Incidence of IS was calculated per 100,000 child-year with its 95% confidence interval. RESULTS: Of the 178 children enrolled, 167 children with definite IS cases were considered for final analyses; 11 were excluded (six diagnosed as probable IS and four diagnosed as suspected IS; one child's parents withdrew consent). Mean age of children with definite IS was 11.6 ± 6 months; 67.7% were males. The overall incidence of IS was 28.9 (95% CI: 23.0-34.8) and 26.1 (95% CI: 22.2-30.0) per 100,000 child-year in children < 1 year and < 2 years of age, respectively. The majority of IS cases (20 [12.0%]) were reported in children aged 6 months. Most children (98.2% [164/167]) recovered, two (1.2%) children recovered with sequelae and one (0.6%) child died of septic shock. CONCLUSIONS: The incidence of IS remained low and stable in Singaporean children aged < 2 years during the study period (May 2002 to June 2010). TRIAL REGISTRATION: NCT01177839.

Management of acute testicular pain in children: changing trends with improvements in scrotal ultrasonography over 18 years.

Introduction: Doppler scrotal ultrasonography (US) is the modality of choice in diagnosing testicular torsion. We aimed to evaluate the performance of scrotal US in diagnosing testicular torsion over the past 18 years in our institution and determine the factors contributing to the length of wait times for it. Methods: A retrospective review was conducted of boys who presented with acute scrotal pain from 2014 to 2015. US reports, operative findings, final diagnosis and key time points of the patients' journey (time to emergency department consultation, time to admission, time to US and time to operating theatre [OT]) were collected. US performance results were compared with those observed in a historical cohort from 1998 to 2004. Wait times were compared between operated and non-operated patients. Results: Data from 519 boys with a mean age of 9.15 years was collected. Of these, 438 (84.4%) boys had undergone initial scrotal US; of these scrotal US cases, 28 were surgically explored, with 23 confirmed to have torsion. Another five cases were explored without prior US, and all were confirmed to have torsion. Performance analysis of US showed a sensitivity of 100% and a specificity of 98.8%. There was no significant difference between wait times of operated and non-operated patients. Time to US (P < 0.0001, r = 0.96) and time to OT (P < 0.0001, r = 0.64) correlated significantly with the total time from presentation to surgery. Conclusion: There has been an improvement in the diagnostic performance of scrotal US for testicular torsion over the past 18 years. Quality improvement programmes targeted at reducing wait times for patients presenting with acute scrotum should target time to US and time to OT.

Complications of Caesarean delivery part 1: Early complications.

Introduction: With the rise in Caesarean deliveries, complications related to the procedure are increasingly encountered. Sonography has an indispensable role in the assessment of these complications and is often the first-line investigation of choice.Topic Description: Part 1 of this pictorial review summarises the early complications unique to and associated with Caesarean deliveries. Discussion: Acute haemorrhagic complications include retained products of conception, subfascial and bladder flap haematomas and, rarely, postpartum uterine dehiscence or rupture and iatrogenic vascular complications. Infective complications include puerperal and wound infections. Key sonographic features of these conditions are illustrated. Pitfalls, mimics, limitations and indications for cross-sectional imaging are discussed. Conclusion: Sound knowledge of the sonographic features of common early complications of Caesarean delivery will facilitate accurate diagnosis, timely management and improved patient outcomes.

Complications of Caesarean delivery part 2: Non-pregnant and pregnancy-related complications.

Introduction: With the rise in Caesarean deliveries, complications related to the procedure are increasingly encountered. Sonography has an indispensable role in the assessment of these complications and is often the first-line investigation of choice.Topic description: Part 2 of this pictorial review summarises the non-pregnant and pregnancy-related complications of Caesarean deliveries. Discussion: Non-pregnant complications include Caesarean scar defects, scar endometriosis and malpositioned intrauterine devices. Complications related to future gestations include scar ectopic pregnancy, abnormal placentation and intrapartum uterine dehiscence or rupture. Key sonographic features of these conditions are illustrated. Pitfalls, mimics, limitations and indications for cross-sectional imaging are discussed. Conclusion: Sound knowledge of the sonographic features of common non-pregnant and pregnancy-related complications of Caesarean delivery will facilitate accurate diagnosis, timely management and improved patient outcomes.

Tropical pyomyositis and necrotizing fasciitis.

Pyomyositis is a purulent infection of skeletal muscle that arises from hematogenous spread, usually with abscess formation. Necrotizing fasciitis is a more severe, rapidly progressive infection involving the superficial and deep fascia with necrosis and fluid collections that can be life threatening if left untreated. Both conditions may coexist, and concomitant cellulitis is often seen. A high incidence of these diseases occurs in the tropics, but they are increasingly being seen in temperate countries, due in part to their association with immunodeficiency conditions such as human immunodeficiency virus (HIV) infection, diabetes mellitus, and organ transplantation. This article aims to familiarize physicians with these entities, review their clinical manifestations and imaging features, and highlight the role of imaging in the management of patients with these conditions.

Ultrasound and alternative multimodality imaging of intra-abdominal and pelvic cystic masses in the newborn.

Introduction: Ultrasound is used commonly to detect and diagnose intra-abdominal and pelvic cystic masses in the newborn as it is easily available, relatively low cost, and non-invasive. Discussion: The diagnosis can be made or narrowed down by determining the location, size, sonographic features, organ involvement, and internal vascularity. The differential diagnoses include hydronephrosis, multicystic dysplastic kidney, adrenal haemorrhage, cystic teratomas, ovarian cysts, enteric cysts, meconium cysts, and liver haemangiomas. With the appropriate radiological knowledge, the ultrasound practitioner can help obtain an accurate diagnosis. Conclusion: This pictorial essay will familiarise the reader with the different common causes of intra-abdominal and pelvic masses detected on ultrasound through a wide range of conditions. The role of ultrasound in the evaluation of these conditions will be discussed and alternative imaging correlates will be offered.

Ultrasound in the evaluation of necrotic bowel in children: A pictorial essay.

Necrotic bowel is a serious condition involving death of gastrointestinal tissue. The diagnosis is difficult to make clinically, and plain radiography is often inconclusive. Ultrasonography is an inexpensive, portable and readily available complementary diagnostic tool. In some cases, ultrasonography can detect features of necrotic bowel earlier than plain radiography or when plain radiography is equivocal and does not correlate with the clinical findings. This pictorial essay aims to compare the ultrasonography features of normal bowel and necrotic bowel in children. The role of ultrasonography and the ultrasonographic features of necrotic bowel will be illustrated by discussing some of the causes of necrotic bowel in children. Correlation with plain radiographs and pathological specimens is made. Frequent causes of necrotic bowel in neonates include necrotising enterocolitis, malrotation with small bowel volvulus and incarcerated inguinal hernias. Causes in older children include intussusception, complications of Meckel's diverticulum, post-surgical adhesions, internal hernias and vasculitic abnormalities. Ultrasonography features suggestive of necrotic bowel include persistently dilated loops of aperistaltic bowel, increase or decrease of bowel wall thickness, intramural or portal venous gas, loss of bowel wall perfusion, and free intraperitoneal gas and fluid. The diagnosis of necrotic bowel may be made earlier on ultrasonography than on abdominal radiographs alone. This pictorial essay will familiarise the reader with the role of ultrasonography and the ultrasonographic features of necrotic bowel through a wide range of conditions that may cause necrotic bowel in children. Familiarity with these findings will facilitate timely imaging diagnosis of necrotic bowel before complications develop.

Atypical presentation of acute fulminant neonatal necrotising enterocolitis: diagnostic superiority of sonographic evaluation over plain radiography of abdomen.

A female preterm infant was born to a non-consanguineous couple at 35 weeks of gestation. On day 8 of life, while on full feeds, she developed prolonged apnoea and bradycardia, requiring respiratory support. Her abdomen was soft with unremarkable serial abdominal X-rays. Her septic screen was negative. Metabolic acidosis was worsening despite treatment. Echocardiography showed evidence of high pulmonary pressures. With further deterioration, an ultrasound scan of the abdomen was requested in view of the rising suspicion of abdominal pathology in the absence of sepsis and metabolic disorders. Mural oedema, pneumatosis and portal venous gas, consistent with diagnosis of necrotising enterocolitis, were noted in the ultrasound images. An emergency laparotomy showed extensive small bowel necrosis. Despite maximal medical support, the infant died. This case highlights the importance of imaging using an ultrasound scanner in the diagnosis of necrotising enterocolitis in preterm infants having intractable metabolic acidosis, subtle abdominal signs and unremarkable abdominal X-rays.

A 7-week-old female infant with a left thigh swelling.

This case is presented to illustrate the imaging and clinical findings of a condition of interest to orthopedic surgeons. The initial findings are noted on this page. The clinical and imaging diagnoses are presented on the following pages.

An update of paediatric intussusception incidence in Singapore: 1997-2007, 11 years of intussusception surveillance.

INTRODUCTION: Understanding baseline epidemiology of intussusception (IS) in different geographical settings is important for the safety assessment of rotavirus vaccines. This paper presents IS surveillance data from Singapore between 1997 and 2007, including the period between November 2005 and December 2007 when rotavirus vaccines (primarily Rotarix) were available to newborns in Singapore. MATERIALS AND METHODS: Case ascertainment, collection, analyses and presentation of IS data was done as per recommendations of the Brighton Collaboration Working Group. For estimating the IS incidence rate in infants, live births for the years of the study were used as denominators, while for incidence in children age <2 years, the expected numbers of infant deaths occurring between 1 and 2 years of age was deducted from the combined live births for the 2 years, to obtain the denominator. RESULTS: The incidence of IS among children aged <1 year throughout this 10-year period was higher than the incidence of IS in children between 1 and 2 years of age. In 2005, 2006 and 2007, the incidence of IS per 100,000 was 39.9, 26.4 and 35.6 in children aged <1 year and 26.2, 23.8 and 28.7 in children <2 years. CONCLUSION: This IS surveillance study provides reassuring preliminary evidence that there is no increase in the incidence of IS in Singapore after the introduction of rotavirus vaccines (including Rotarix) in Singapore.

Congenital osteofibrous dysplasia associated with pseudoarthrosis of the tibia and fibula.

The association between congenital pseudoarthrosis and osteofibrous dysplasia of the tibia and fibula is a rare entity that has been recently recognized. We report a male newborn who was found to have swelling and deformity of the left lower leg. Radiographs and magnetic resonance imaging showed an extensive destructive lesion of the tibial shaft, with dysplastic congenital pseudoarthrosis of the lower fibula. Histopathological examination confirmed the diagnosis of congenital pseudoarthrosis of the tibia and fibula with underlying osteofibrous dysplasia involving both bones. Immunohistochemical stains showed cytokeratin positivity.

Infantile lipofibromatosis of the upper limb.

The imaging features of extensive lipofibromatosis presenting in a 1-day-old female infant are reported. This lesion involved her entire right upper limb, extending from the axilla to the palm of the hand. Radiographs showed marked deformity and thinning of all the right upper-limb bones due to pressure effect of soft-tissue enlargement, especially affecting the distal humerus and proximal forearm bones. Magnetic resonance imaging showed a huge soft-tissue mass infiltrating most of the muscles of the entire upper limb, with bony erosion. The mass was largely T1-isointense, moderately T2-hyperintense and showed marked enhancement. There were intra-lesional signal changes consistent with fatty elements. A lesion debulking procedure was performed and the histology was that of lipofibromatosis. The limb was found to be non-viable after the procedure and a subsequent above-elbow amputation was performed. Although the resection margins were not clear, she had no further recurrence over a subsequent 3-year follow-up period.

Colour Doppler ultrasonography replacing surgical exploration for acute scrotum: myth or reality?

BACKGROUND: Traditionally, every patient with an acute scrotum needed surgical exploration for definitive exclusion of testicular torsion. OBJECTIVE: In this study, we aimed to evaluate the improved accuracy in clinical diagnosis with colour Doppler Ultrasonography (US) added to normal clinical assessment. MATERIALS AND METHODS: We retrospectively reviewed 626 patients, who presented with acute scrotal pain between January 1998 and June 2004. Following history and physical examination, the patients either proceeded directly to surgery or underwent US examination. If clinical suspicion of testicular torsion persisted after US, the patients would still undergo scrotal exploration. RESULTS: Of the 294 patients who had routine scrotal exploration without preliminary US, only 23 (7.8%) were found to have testicular torsion. Amongst the 332 cases that had initial US, 9 (2.7%) patients revealed testicular torsion that was confirmed at subsequent surgery. The remaining 323 patients had initial negative US, but 29 were explored eventually on clinical indications. Of these, 4 (1.2% of 323) cases were diagnosed intra-operatively as testicular torsion. None of the remaining 294 patients who were managed conservatively proved to have testicular torsion after a minimum follow-up of 2 weeks. For testicular torsion, US yielded a sensitivity of 69.2% (95% confidence interval =38.9-89.5), specificity of 100% (95% CI=98.5-100), positive predictive value of 100% and negative predictive value of 97.5%. CONCLUSIONS: US has proven to decrease the number of emergency scrotal explorations, length of hospital stay and hence reduce the cost of management of acute scrotum.

The role of imaging in the staging and treatment planning of primary malignant bone tumors in children.

The accurate staging of primary bone tumors in children is critical for treatment planning. Limb salvage operations can now be performed with excellent outcomes in suitable patients. The purpose of this article is to review the current state of imaging techniques and their roles in enabling accurate staging and treatment planning to be performed in pediatric patients with primary bone tumors.

Skeletal tuberculosis in children.

The objective of this review is to present the imaging findings of skeletal tuberculosis in children. The incidence of tuberculosis is increasing and skeletal tuberculosis accounts for 10-20% of all extra-pulmonary cases. The most common manifestations of skeletal tuberculosis in children are spondylitis, arthritis and osteomyelitis. Tuberculous spondylitis involves the intervertebral disc only late in the disease. Subligamentous spread of the infection may lead to multiple levels of vertebral body involvement that may either be continuous or skipped. Extension of the disease into the paravertebral or extra-dural space may occur. Tuberculous arthritis usually occurs as a result of metaphyseal spread to the joint. Tuberculous osteomyelitis may appear as cystic, well-defined lesions, infiltrative lesions or spina ventosa. The latter is a term used to describe a form of tuberculous osteomyelitis where underlying bone destruction, overlying periosteal reaction and fusiform expansion of the bone results in cyst-like cavities with diaphyseal expansion. Radiographs are still the mainstay of evaluation of patients with bony lesions. Ultrasonography can detect soft-tissue extension of the bony lesions and guide drainage or biopsy procedures. CT accurately demonstrates bony sclerosis and destruction, especially in areas difficult to assess on radiographs such as the posterior elements of the vertebral body. MRI is the modality of choice in evaluating early marrow involvement and soft-tissue extension of the lesion.

Primary bone tumors of adulthood.

Imaging plays a crucial role in the evaluation of primary bone tumors in adults. Initial radiographic evaluation is indicated in all cases with suspected primary bone tumors. Radiographs are useful for providing the diagnosis, a short list of differential diagnosis or at least indicating the degree of aggressiveness of the lesion. More detailed information about the lesion, such as cortical destruction or local spread, can be obtained using cross-sectional imaging techniques such as computed tomography and magnetic resonance imaging. This article discusses the characteristic features of the more common primary bone tumors of adulthood, and also the pre-treatment evaluation and staging of these lesions using imaging techniques.

Percutaneous drainage of a postoperative intraspinal hematoma using a Tuohy needle.

A 78-year-old man developed a large subdural hematoma extending from T12 to L3 levels following L3 laminectomy and L3-5 posterior spinal fusion. He had associated neurological signs and symptoms. MR imaging showed typical signal characteristics of a subacute intraspinal subdural hematoma. Percutaneous drainage was successfully performed under CT guidance by inserting a Tuohy needle through the L3 laminectomy defect. The catheter packaged with the Tuohy needle was inserted cranially into the hematoma and 30 ml of blood was aspirated. Follow-up MR imaging confirmed resolution of the hematoma and the patient made a rapid recovery.