Review of standard paediatric neuroradiology MRI protocols from 12 UK tertiary paediatric hospitals: is there much variation between centres?

AIM: To investigate how magnetic resonance imaging (MRI) examinations are protocolled in tertiary paediatric neuroradiology centres around the UK for some of the more common presentations encountered in paediatric neuroradiology, and to identify any variations of note. MATERIALS AND METHODS: All 19 UK tertiary paediatric neuroradiology centres registered with the British Society of Neuroradiologists-Paediatric Group were contacted and asked if they could provide a copy of their standard MRI protocols. Twelve responded (63%) and 10 of the more common presentations were selected and the standard acquired sequences obtained at each participating centre were compared. Where available the collated protocols were also compared against current published guidance. RESULTS: The basic sequences carried out by centres around the UK are similar; however, there are lots of variations overall. The only standardised protocol currently being implemented nationally in paediatric imaging is that for brain tumours. Otherwise, chosen protocols are generally dependent on the preferences and technical capabilities of individual centres. Suggested published protocols also exist for non-accidental injury (NAI), multiple sclerosis, epilepsy, and head and neck imaging. CONCLUSIONS: The differences in MRI protocolling depend in part on technical capabilities and in part on the experience and preferences of the paediatric neuroradiologists at each centre. For most presentations, there is no consensus as to what constitutes the perfect protocol. The present results will be useful for specialist centres who may wish to review their current protocols, and for more generalist centres to use as a reference to guide their MRI protocolling.

Epilepsia Partialis Continua that Improved in a Pediatric Patient with Sub-dural Empyema.

In epilepsia partialis continua (EPC), the EEG tracings may fail to show epileptiform activity because the electrical activity is too subtle or too deep to be picked up by surface electrodes. EPC can occur at any age and may have many etiologies, including genetic, metabolic, structural, infectious, and idiopathic. Typical EEG in EPC is characterized by discharges of cortical origin that commonly consist of sharp waves, spikes or periodic lateralized epileptiform discharge; however, EEG findings at large are variable and often not even identified. Here we present a pediatric case of EPC in the setting of subdural empyema with atypical EEG seizure associated with focal clonic activity who made rapid improvements.

Acquired torticollis due to primary pyomyositis of the paraspinal muscles in an 11-year-old boy.

Torticollis is characterised by tilting and rotation of the cervical spine in opposite directions. Causes can be congenital or acquired. Primary pyomyositis is a rare subacute deep bacterial infection of skeletal muscles that typically affects individuals under 20 years of age from tropical countries. Infrequently, pyomyositis occurs in individuals from temperate regions, usually in immunocompromised adults, and this is defined as secondary pyomyositis. We report a case of acquired torticollis due to primary pyomyositis of the paraspinal muscles in a previously healthy boy from the UK. A prolonged course of antibiotics and physiotherapy led to a complete resolution of his illness. We review how to differentiate pyomyositis from focal myositis, a more common inflammatory muscular cause of acquired torticollis.

Inferior epigastric artery pseudoaneurysms.

INTRODUCTION: Inferior epigastric artery (IEA) pseudoaneurysms are recognised complications of abdominal wall procedures, and a variety of approaches including surgical excision and ligation, percutaneous procedures and conservative management have been employed in treating this rare complication. METHODS: We describe a case of an IEA pseudoaneurysm diagnosed on computed tomography (CT) angiography, 14 days following a laparoscopic assisted low anterior resection, which was managed successfully with surgical excision and ligation. A review of the literature identified 32 reports of this complication since 1973 with 69% of cases occurring since 2000. FINDINGS: The main aetiology of IEA pseudoaneurysm was abdominal surgery (n=20); 65% of cases were attributable to abdominal wound closure or laparoscopic surgery. Two-thirds (66%) of patients presented between 11 and 63 days, and all except 1 case presented with discomfort, abdominal mass or haemodynamic instability. Colour Doppler ultrasonography was the imaging modality of choice (n=18), either alone or in combination with computed tomography and/or angiography. Surgical ligation and excision and percutaneous coil embolisation formed the mainstay of attempted treatments (69%), particularly following treatment failure using an alternative technique. CONCLUSIONS: The incidence of iatrogenic IEA pseudoaneurysms appears to be increasing. Awareness of this rare complication is of clinical importance to avoid excessive morbidity for affected individuals.

Craniopharyngeal duct: a cause of recurrent meningitis.

Identification of the cause of recurrent meningitis may pose a diagnostic challenge. Evaluation of a patient with recurrent meningitis calls for meticulous review of skull base structures by cross sectional imaging to exclude any underlying anatomical abnormality. Our case highlights the importance of excluding persistent craniopharyngeal duct, a rare but treatable cause of recurrent meningitis. The isolation of Streptococcus pneumoniae in recurrent meningitis may be a clue to the presence of a skull base abnormality. Craniopharyngeal canals have been classified depending on their qualitative and quantitative imaging features. Such imaging based classification is important for identification of patients with associated potential pituitary involvement and also for appropriate surgical planning. Controversy exists as to the approach to surgical treatment of craniopahryngeal duct. The persistent craniopahryngeal duct in our patient was successfully treated by an endoscopic transsphenoidal approach.

Appendicitis in a Spigelian hernia: an unusual cause for a tender right iliac fossa mass.

Spigelian hernias are a rare type of hernia through the Spigelian aponeurosis, whose contents commonly include omentum or small bowel. In the absence of incarceration or strangulation, they can be difficult to diagnose clinically. In the emergency setting, they can present rarely as a painful abdominal mass and computed tomography provides a reliable diagnostic imaging modality. We report an emergency presentation of a Spigelian hernia containing the appendix.

Intra-operative 3-T MRI for paediatric brain tumours: challenges and perspectives.

MRI is the ideal modality for imaging intracranial tumours. Intraoperative MRI (ioMRI) makes it possible to obtain scans during a neurosurgical operation that can aid complete macroscopic tumour resection­a major prognostic factor in the majority of brain tumours in children. Intraoperative MRI can also help limit damage to normal brain tissue. It therefore has the potential to improve the survival of children with brain tumours and to minimise morbidity, including neurological deficits. The use of ioMRI is also likely to reduce the need for second look surgery, and may reduce the need for chemotherapy and radiotherapy. Highfield MRI systems provide better anatomical information and also enable effective utilisation of advanced MRI techniques such as perfusion imaging, diffusion tensor imaging, and magnetic resonance spectroscopy. However, high-field ioMRI facilities require substantial capital investment, and careful planning is required for optimal benefit. Safe ioMRI requires meticulous attention to detail and rigorous application of magnetic field safety precautions. Interpretation of ioMRI can be challenging and requires experience and understanding of artefacts that are common in the intra-operative setting.

Role of vascular access as a risk factor for infections in hemodialysis.

Infections are a major cause of morbidity and mortality in chronic hemodialysis patients. This single center prospective study was carried out to determine the incidence and risk factors for infection in hemodialysis patients and plan appropriate strategies to reduce the risk of infection. A total of 84 consecutive patients who were initiated on hemodialysis over a 2-year period were followed until they either received a kidney transplant or died. In our hospital, as a policy, patients are offered hemodialysis as a bridge therapy to a kidney transplant. The mean duration of follow up was 3 months (range 1-11.8 months). The factors associated with at least one episode of infection were evaluated. Statistical analysis was done by multivariate stepwise logistic regression method. Fifty-one patients had a total of 57 episodes (67.8%) of infection. Of the 44 episodes of acute bacterial infections, vascular access exit site infection was the commonest followed by septicemia (13 patients, 29.5%). Staphylococcus aureus was the commonest bacterial isolate observed in 14 patients. On multivariate analysis, three risk factors for infection were identified: (1) nonarteriovenous fistula (AVF) vascular access for hemodialysis (p = 0.02), (2) increased number of hemodialysis sessions (p = 0.03), and (3) lower serum calcium level (p = 0.02). NonAVF vascular access was found to be the most important risk factor for infection in hemodialysis patients. Creation of an AV fistula, preferably at an early stage, appears beneficial for minimizing the risk of infection even in patients who are on short-term hemodialysis as a bridge therapy towards a kidney transplant.

Calcitropic hormonal status in north Indian patients with end-stage renal disease.

BACKGROUND: Bone disease in chronic renal failure has a wide spectrum that includes both high and low turnover conditions. Specific preventive and therapeutic measures require knowledge of the nature of bone involvement. Bone biopsy with static and dynamic histomorphometry is the gold standard for characterization of renal bone disease. However, non-invasive biochemical tests, especially serum intact parathyroid hormone (PTH), have a good correlation with histomorphometry. We studied the clinical and biochemical profile of bone disease in a sample of north Indian patients with chronic renal failure. METHODS: Twenty-nine patients of chronic renal failure were evaluated clinically, radiologically (subperiosteal erosions on hand X-rays) and biochemically (serum calcium, phosphorus, total alkaline phosphatase, intact PTH, osteocalcin, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D). Bone histomorphometry could be done in 4 patients. RESULTS: Serum intact PTH within or below the non-uraemic normal range, an index of low bone turnover, was seen in 17 (58.6%) patients. Serum osteocalcin, a bone formation marker, was within or below the non-uraemic normal range in 65.5% patients. Serum intact PTH and osteocalcin had a significant positive correlation (r = 0.6). Patient groups with clinical or radiological evidence of bone disease had serum intact PTH and osteocalcin levels comparable to those lacking such features. Serum intact PTH and total alkaline phosphatase were lower in haemodialysed (n = 25) patients than in those who had not received haemodialysis (n = 4). Low (< 10 ng/ml) serum 25-hydroxyvitamin D levels were seen in 7 (24%) patients while 1,25-dihydroxyvitamin D was low (< 15.9 pg/ml) in 20 (69%) patients. The biochemical parameters accurately reflected the bone histology (n = 4). CONCLUSIONS: Our data show that the majority of north Indian patients with chronic renal failure have biochemical evidence of low bone turnover. Empirical use of calcium salts and active vitamin D analogues without documentation of parathyroid status carry the risk of further suppression of bone turnover.

Endovascular covered stent repair of an intercostal artery patch dehiscence from a descending thoracic aortic aneurysm graft.

PURPOSE: To describe the use of endovascular techniques to repair a descending thoracic aortic pseudoaneurysm at a site of patch dehiscence. METHODS AND RESULTS: A 63-year-old hypertensive, diabetic female with a 4-cm aneurysm in the descending thoracic aorta underwent surgical repair with a 35-mm Dacron graft. Dehiscence of the intercostal arterial patch produced a large, 6-cm-diameter pseudoaneurysm that extended into the left thoracic cavity. An endovascular repair was planned using a Dacron stent-graft. Despite induced hypotension and an exteriorized, stiff exchange wire to enhance control of the delivery balloon catheter, the initial attempt failed to close the suture line defect. A customized polytetrafluoroethylene-covered, balloon-expandable stent was successfully deployed using the original stent-graft as a landmark. At 6 months, the contrast-enhanced spiral computed tomographic scan showed patency of the stent-graft and resorption of the pseudoaneurysm. CONCLUSIONS: This communication describes the management of a surgical complication using balloon-expandable covered stents in contrast to either conventional surgery or self-expanding stent-grafts. Transesophageal ultrasound monitoring delineated the suture line leak, identified the position of the stent-grafts, and accurately demonstrated closure of the defect.

Juxtaposed "kissing" stents as a technique to preserve both limbs of a bifurcating renal artery.

Percutaneous revascularization with balloon expandable stent placement and/or balloon angioplasty has been proven to be an effective alternative for renal artery bypass surgery for management of renal artery stenosis. Endovascular stent deployment has been proven to be superior to balloon angioplasty alone, especially for ostial lesions in terms of maintaining long-term patency. Here we describe a case report for deployment of two Palmaz stents with simultaneous utilization of brachial and femoral routes. Technical aspects for this procedure, especially adaptation of coronary guide wire systems in management of renal artery stenosis were discussed.

Utility of various clinical, noninvasive, and invasive procedures for determining the causes of recurrence of myocardial ischemia or infarction > or = 1 year after percutaneous transluminal coronary angioplasty.

In patients with recurrent symptoms > or = 1 year after successful percutaneous transluminal coronary angioplasty (PTCA), the decision of whether to proceed directly with coronary angiography or to evaluate the patient noninvasively can be difficult. To determine which demographic, historical, clinical, and laboratory factors are useful in helping to make this decision, 76 consecutive patients who presented > 1 year (768 +/- 309 days) after successful PTCA with resolution of symptoms were studied. The initial PTCA successfully treated all stenoses (except chronically occluded vessels) in all major vessels and segments. The patient group was predominantly men (68%), with a mean age of 64 +/- 10 years. A prior myocardial infarction was present in 39 patients (51%), and there was a mean of 2.8 risk factors per patient. In patients who presented with recurrent symptoms, the Canadian Cardiovascular Society functional class was 2.0 +/- 0.9; 2 patients presented with acute infarctions, 57 were admitted to the hospital with unstable angina, and 17 had stable angina. New electrocardiographic changes at rest were found in 19 of 74 patients (26%) with recurrent angina. A thallium stress test was performed in 40 patients (53%), with a sensitivity of 77% and a specificity of 36% for the presence of a significant stenosis. No nonangiographic variable was predictive of angiographic findings. At angiography, the number of coronary arteries with > or = 50% diameter narrowing was 1.4 +/- 1.0. Forty-two patients had stenosis at a new site, 7 had restenosis, and 27 had no new stenoses.(ABSTRACT TRUNCATED AT 250 WORDS)