Melanie P. Hiorns

Current practice in paediatric videofluoroscopy

Use of the videofluoroscopy swallow study (VFSS), also known as the modified barium swallow (MBS), continues to increase in children. This article reviews the scope and limitations of the examination, explores the current techniques and illustrates some of the main findings. As moving images are key to the understanding of the use of this technique short videos are available in the on-line version of this paper.

Malfunctioning central venous catheters in children: a diagnostic approach.

Central venous access is increasingly becoming the domain of the radiologist, both in terms of the insertion of central venous catheters (CVCs) and in the subsequent management of these lines. This article seeks to provide an overview of the CVC types available for paediatric patients and a more detailed explanation of the spectrum of complications that may lead to catheter malfunction. A standard catheter contrast study or ‘linogram’ technique is described. The normal appearances of such a study and a detailed pictorial review of abnormal catheter studies are provided, together with a brief overview of how information from catheter investigations can guide the management of catheter complications.

The Role of Imaging During Extracorporeal Membrane Oxygenation in Pediatric Respiratory Failure

OBJECTIVE Extracorporeal membrane oxygenation (ECMO) is increasingly widely used in pediatric respiratory failure. Despite playing a key part in patient management during ECMO, the role of radiology is not widely reported. We discuss the principles of ECMO support and the normal imaging appearances. Radiologic findings arising from the complications of ECMO are highlighted. CONCLUSION Radiology has a central role in establishing well-designed imaging protocols and vigilant reporting of ECMO apparatus positions and complications.

Imaging of urinary tract lithiasis: who, when and how?

Urolithiasis remains rare in children who are estimated to only account for 2–3% of all patients with stone disease. However, there is an upward trend in incidence. The incidence of stones in adults has increased in the last 30 years and this rise is almost certainly paralleled in children, with some institutions reporting up to a five-fold increase over the last decade [1]. Although infection remains a major aetiological factor in stone formation, especially in boys, there is increasing recognition of the numbers of children affected by a metabolic predisposition to stone formation and this proportion appears to be increasing [1, 2], and hence every child who presents with urolithiasis should undergo a metabolic work-up [3]. In a study performed in the UK, 44% of children had a metabolic abnormality, 30% were classified as infective, and 26% idiopathic [2]. A study from Texas found a similar pattern [4]. Coexisting urinary tract infection can of course mask underlying metabolic causes. The rate of stone recurrence is lower in children compared to adults and the majority of stone disease is now managed, as in adults, by lithotripsy or endourological techniques; open surgery has decreased dramatically. Epidemiology

The predictive value of a repeat micturating cystourethrogram for remnant leaflets after primary endoscopic ablation of posterior urethral valves

OBJECTIVE We routinely perform a cystourethroscopy 3 months after initial ablation of posterior urethral valves. The aim of this study was to determine the predictive value of the urethral appearance on preoperative micturating cystourethrogram (MCUG) for further valve resection at check cystoscopy. PATIENTS AND METHODS We retrospectively reviewed 31 consecutive boys (aged 4-18 months) who underwent check cystoscopy and repeat MCUG between 2006 and 2008. RESULTS Repeat MCUG suggested remnant valves in 10, but no residual leaflets were identified cystoscopically in 4. In 20 boys, the valves appeared completely ablated on MCUG but valve leaflets received further resection in 10. One study was undiagnostic. Residual valves were resected in 83% (5/6) where valves and urethral dilatation were noted on MCUG. Where MCUG suggested either valves or persistent dilatation alone, further resection occurred in 40% (4/10). Remnant leaflets were also present in half of those (7/14) in whom the repeat MCUG had shown complete ablation and resolved/reduced posterior urethral dilatation. CONCLUSIONS The positive predictive value of valve leaflets and/or posterior urethral dilatation on repeat MCUG for subsequent resection of valve remnants was 56%; the negative predictive value was 50%. We found repeat MCUG alone imprecise in excluding residual valve tissue and recommend check cystoscopy in all.

Imaging of the urinary tract: the role of CT and MRI

Computed tomography (CT) and magnetic resonance imaging (MRI) are increasingly valuable tools for assessing the urinary tract in adults and children. However, their imaging capabilities, while overlapping in some respects, should be considered as complementary, as each technique offers specific advantages and disadvantages both in actual inherent qualities of the technique and in specific patients and with a specific diagnostic question. The use of CT and MRI should therefore be tailored to the patient and the clinical question. For the scope of this article, the advantages and disadvantages of these techniques in children will be considered; different considerations will apply in adult practice.

Gastrointestinal tract imaging in children: current techniques

Imaging of the gastrointestinal (GI) tract in children continues to evolve, with new techniques, both radiological and non-radiological, being added to the repertoire. This article provides a summary of current imaging techniques of the GI tract (primarily the upper GI tract) and the relationship between those techniques. It covers the upper GI series and other contrast studies, US, CT and MRI. Note is also made of the contribution now made by capsule endoscopy (CE). Abdominal emergency imaging is not covered in this article.

Imaging of inflammatory bowel disease. How

Imaging of the small bowel has changed radically over the last few years. It is still the case that the mesenteric small intestine has not been conquered by fibre-optic endoscopy and the small bowel remains the most difficult segment of the alimentary tract to examine because of its unique anatomy and remote location. However, the changes that have been led by advances in adult practice are rapidly being included in paediatric practice and the landscape has changed beyond recognition. Traditionally the small bowel (barium) follow through (SBFT) has been the investigation of choice for that otherwise inaccessible length of gut between the duodenum and the ileocaecal valve. Whilst it is still a widely practised examination by radiologists [1] it is being largely overtaken by other imaging modalities with CT, MRI and capsule endoscopy (CE) all competing for the territory. At the end of the last century, proponents of enteroclysis were predicting the eventual decline of the SBFT (in adults) [2] although at that stage, in a ‘state of the art’ article, they were still brave enough to say that ‘only in the small bowel does barium radiography remain unchallenged’. The same authors now write of how radiological investigations complement other techniques [3] but are no longer the mainstay. In 1981, an engineer called Iddan, with expertise in electro-optics, had the original science-fiction-like concept of a tiny capsule that could pass through the gut recording information and transmitting it to the ‘outside world’. In collaboration with a gastroenterologist, the idea was developed, and in 1994 they applied for patents and started feasibility studies. Separately, another gastroenterologist, Swain, together with his colleagues in the UK, showed the first live transmission of the pig intestinal mucosa using commonly available electronic components. Iddan and Swain then collaborated [4] and in 2000 human studies began. The FDA approved the capsule endoscope for clinical use in adults in 2001 and for use in children aged 10– 18 years in 2003. It is used off licence in younger children; with the youngest child being reported so far being 18 months of age. It is more commonly used in children from about the age of 4 or 5 years upwards.

Peliosis hepatis causing inferior vena cava compression in a 3-year-old child

Peliosis hepatis is a rare benign condition characterized by oval or irregular, multiple blood-filled spaces within the liver parenchyma. It is most commonly seen in adults and may be idiopathic, but has various associations including malignancy, infection and drugs. The imaging findings are often non-specific and the condition may be mistaken for multiple abscesses, metastases or vascular malformations. Peliosis hepatis is an especially rare condition in children and to our knowledge only six cases have been described in the literature. Our case describes and illustrates peliosis in a 3-year-old girl and is the first described in any age group to cause complete IVC obstruction. The patient subsequently made a full recovery.

Herniation through the foramen of Winslow presenting as obstructive jaundice

Herniation through the foramen of Winslow is a rare variety of paraduodenal hernia. We report a 19-month-old child with obstructive jaundice due to midgut herniation through the foramen of Winslow with associated volvulus. The herniation and volvulus were precipitated by intestinal malrotation. The patient underwent extraamniotic silo repair of exomphalos major in the neonatal period. Investigation for malrotation is recommended after extraamniotic closure of exomphalos.