Ruth Batty

Imaging the corpus callosum, septum pellucidum and fornix in children: normal anatomy and variations of normality

The midline structures of the supra-tentorial brain are important landmarks for judging if the brain has formed correctly. In this article, we consider the normal appearances of the corpus callosum, septum pellucidum and fornix as shown on MR imaging in normal and near-normal states.

3.0 T MRI of 2000 consecutive patients with localisation-related epilepsy

OBJECTIVES Clinical guidelines suggest that all patients diagnosed with localised seizures should be investigated with MRI to identify any epileptogenic structural lesions, as these patients may benefit from surgical resection. There is growing impetus to use higher field strength scanners to image such patients, as some evidence suggests that they improve detection rates. We set out to review the detection rate of radiological abnormalities found by imaging patients with localised seizures using a high-resolution 3.0 T epilepsy protocol. METHODS Data were reviewed from 2000 consecutive adult patients with localisation-related epilepsy referred between January 2005 and February 2011, and imaged at 3.0 T using a standard epilepsy protocol. RESULTS An abnormality likely to be related to seizure activity was identified in 403/2000 (20.2%) patients, with mesial temporal sclerosis diagnosed in 211 patients. 313/2000 (15.6%) had lesions potentially amenable to surgery. Abnormalities thought unrelated to seizure activity were found in 324/2000 (16.1%), with 8.9% having evidence of ischaemic disease. CONCLUSIONS Since the introduction of the then National Institute for Clinical Excellence guidelines in 2004, the detection rate of significant pathology using a dedicated 3.0 T epilepsy protocol has not fallen, despite the increased numbers of patients being imaged. This is the largest study of epilepsy imaging at 3.0 T to date and highlights the detection rates of significant pathology in a clinical setting using a high-strength magnet. The prevalence of ischaemic disease in this population is significantly higher than first thought, and may not be incidental, as is often reported.

Neuroimaging in non-accidental head injury in children: an important element of assessment

Head injury from physical abuse is unfortunately a common occurrence in our society. It is a major cause of mortality and long-term physical and psychological disability in children. Diagnosis of non-accidental head injury may be difficult, as most infants present with non-specific clinical findings and without external signs of trauma. Neuroimaging plays a fundamental role both for medical management and medicolegal aspects of child abuse. It is therefore imperative for the radiologist to promptly recognise the radiological findings of various forms of non-accidental head injury to render a more accurate opinion. A standardised imaging protocol and good communication between professionals are essential for optimum management.

Paediatric post-septal and pre-septal cellulitis: 10 years' experience at a tertiary-level children's hospital

OBJECTIVE To assess the incidence and complications of pre-septal (pre-SC) and post-septal (post-SC) cellulitis over 10 years. Pre-SC and post-SC are also known as periorbital and orbital cellulitis, respectively. METHODS Retrospective analysis of CT scans. Data included the presence of pre-SC and post-SC, paranasal sinus disease (PNS) and complications. RESULTS Among 125 patients scanned for these suspected diagnoses, 67 had both pre-SC and post-SC, 37 had pre-SC and 4 had post-SC; there were 17 normal scans. 110 patients had PNS. 68/71 (96%) patients with post-SC had PNS. Post-SC complications included orbital and/or subperiosteal abscess (50/71: 30 medial orbital, 10 superomedial, 3 lateral, 2 anteromedial, 2 inferomedial, 1 superior, 1 anterosuperior and 1 not specified), cavernous sinus thrombosis (CST) (1), superior ophthalmic vein (SOV) thrombosis (4) and subdural frontal empyema (2); 1 patient had SOV and CST and subdural empyema. CONCLUSION 71/125 (57%) patients had post-SC. 50/125 (40%) patients imaged for pre-SC/post-SC had orbital abscess; 44/50 (88%) of these involved the medial orbit. Patients can develop solely superior or inferior abscesses that are difficult to identify by axial imaging alone, hence coronal reformatted imaging is essential. 5/125 (4%) patients developed major complications (SOV/CST/empyema), hence imaging review of the head and cavernous sinus region is essential. A diagnosis of post-SC on CT should alert the radiologist because this diagnosis can be associated with an increased incidence (5/71, 7%) of complications. ADVANCES IN KNOWLEDGE We recommend that all patients with a suspected diagnosis of post-SC should undergo CT scan (post-contrast orbits and post-contrast head, with multiplanar reformats and a careful review of the SOV and the cavernous sinus). Particular attention should be paid to exclude intracranial complications including subdural empyema and cerebral abscess. As soon as a diagnosis of post-SC is made, in addition to informing the referring clinical team, urgent opinion should be sought from ear, nose and throat (ENT), neurology and ophthalmology with a view to urgently drain of the paranasal sinuses`.

The use of MR imaging and spectroscopy of the brain in children investigated for developmental delay: What is the most appropriate imaging strategy?

ObjectivesDevelopmental delay is a common problem in paediatric practice and many children with developmental delay are referred for MR imaging. Our study was performed as part of a continuing audit process to optimise our MR protocol and case selection.Materials and methodsWe performed MR imaging and spectroscopy protocol on 157 children with developmental delay. We analysed the effect of these interventions by looking at the overall detection rate of relevant pathology and in particular subgroups of the children.Results71% of the children had normal MR imaging, 10% had non-specific findings and 19% had specific abnormalities on MR imaging. The overall risk of having a specific structural abnormality with isolated developmental was 7.5% but if other neurological symptoms/signs were present the risk was 28%. Two children had abnormal spectroscopic findings, one with tuberous sclerosis and the other with absent brain creatine.ConclusionCase selection for MR imaging is important in children with developmental delay. The best strategies for selecting children for MR are either; not performing MR with developmental delay in one domain only or performing MR with developmental delay in three or four domains or if there are other neurological features.

Effects of failed commissuration on the septum pellucidum and fornix: implications for fetal imaging

In the previous article, we considered the normal appearances of the midline stuctures of the brain as they appear on high-resolution magnetic resonance imaging. In this article, we discuss the effects of failed commissuration on the midline structures. We highlight some of the misconceptions of this process that may lead to misdiagnosis of agenesis of the corpus callosum in utero.

Management of isolated syringomyelia in the paediatric population – a review of imaging and follow-up in a single centre

Abstract Objective. To assess the natural history of isolated syringomyelia in children. Methods. MRI reports from February 2007 to August 2011 mentioning syrinx were identified on Sheffield Childrens PACS database. Scans with syringes having an AP diameter of > 1 mm and extending over at least two vertebral bodies were reviewed. Patients with an identifiable cause such as a Chiari malformation were then excluded. Results. Thirty-nine patients were included with a mean age at diagnosis of 10.6 years. The average syrinx AP diameter was 3.30 mm. The rostrocaudal length of the syringes varied between 2 and 19 vertebral bodies. Twenty-seven out of 39 syringes were thoracic in origin. There were 3 and 6 syringes involving the cervicothoracic and thoracolumbar regions, respectively, with 3 involving the cervical area only. Eleven out of 39 (Group I) patients were found “incidentally” during work-up for adolescent idiopathic scoliosis and these were considered as a separate group. These patients did not have any significant symptoms and were discharged following their scoliosis correction surgery. Syrinx was incidental in 14 further patients (Group II). Of the 14 patients, 11 remained asymptomatic with no change in syrinx morphology throughout follow up. Of the 14 patients, 3 were lost to follow-up. Of the 39 patients, 14 (Group III) presented with progressive back pain without any obvious clinical cause. Of the 14, 10 either improved or remained the same. Of the14 patients, 3 underwent lumbar puncture, 1/14 having myelography. All 4/14 patients reported significant pain reduction on follow up following intervention. Conclusion. Idiopathic syrinx is a benign pathology, which can be managed expectantly. Most cases remain stable or improve over time. In a small minority who have progressive back pain, we have found that lumbar puncture may be helpful in reducing symptoms.

Is There a Causal Relationship Between Open Spinal Dysraphism and Chiari II Deformity?A Study Using in Utero Magnetic Resonance Imaging of the Fetus

BACKGROUND: Chiari II deformity is associated with open spinal dysraphism. A causal relationship has been proposed by McLone and Knepper. This article evaluates that hypothesis. OBJECTIVE: To establish the frequency of Chiari II deformity in fetuses with open spinal dysraphism, assess whether meningocele sac neck area and volume influence the severity of posterior fossa changes, and assess whether the severity of associated findings (ventriculomegaly, amount of extracerebral CSF) are associated with Chiari II deformity. METHODS: Sixty-five fetuses with open spinal dysraphism were compared with gestationally aged matched “normal” fetuses on ultrafast MR images. Cerebellar vermis and bony posterior fossa surface area were measured on midline sagittal images. Hindbrain herniation was noted if present. In the open spinal dysraphic group, sac neck area and volume were measured. Ventriculomegaly was assessed by linear measurement of the trigone of the lateral ventricle and extracerebral CSF depth was measured maximally over the lateral surface of the cerebral hemispheres. RESULTS: Fifteen of 65 fetuses with open spinal dysraphism did not have Chiari II deformity. Neck area and volume of the sac did not correlate with the presence of Chiari II deformity or reduction in bony posterior fossa size. CONCLUSION: A relatively high proportion of fetuses with open spinal dysraphism do not have Chiari II deformity in utero. There is a lack of correlation between indicators of spinal dysraphism severity and the extent of the posterior fossa abnormality. This raises some interesting questions about the causality of the Chiari II deformity.

Diffusion‐weighted imaging and magnetic resonance spectroscopy findings in a case of neonatal hypoglycaemia

Rachel E Musson MBCHB MRCP, Ruth Batty MBBS MRCP FRCR, Santosh R Mordekar MD MRCP MRCPCH, Iain D Wilkinson PHD ARCP FIPEM, Paul D Griffiths PHD FRCR, Daniel JA Connolly BSC MRCP FRCR 1 Radiology Department, Royal Hallamshire Hospital, Sheffield, UK. 2 Department of Neurology, Sheffield Childrens Hospital, Sheffield, UK. 3 Academic Unit of Radiology, University of Sheffield, Sheffield, UK. 4 Radiology Department, Sheffield Childrens Hospital, Sheffield, UK. Correspondence to: rachel.musson@sth.nhs.uk

MRI in children with global developmental delay - a retrospective case note review

Magnetic resonance imaging (MRI) is recommended as a part of investigation of children with global developmental delay (GDD) and additional symptoms, but not for those with isolated GDD. Our aims were to review our local experience on the frequency of abnormalities of the brain in children with developmental delay and assess if abnormalities are as common in our children with isolated GDD as those with GDD and additional symptoms. One hundred and thirty-two children referred for MRI of the brain as part of their investigation for GDD between January 1998 and December 2006 were identified from a local database of MRI in our radiology department. Clinical features up to the point of referral for MRI were noted and participants divided into two groups: isolated GDD, and GDD with additional features. MRI reports were classified as normal or abnorma l. Fishers exact test was used to identify statistical differ ences in the prevalence of MRI abnormalities between the groups. Nine (6.8%) had isolated GDD and 123 (93.2%) had GDD and additional symptoms. Four (44.4%) of the children with isolated GDD had abnormal MRI. 68 (55.3%) children with GDD and additional symptoms had abnormal MRI. Children with GDD and additional symptoms were 1.51 times more likely to have an abnormal MRI than children with isolated GDD (95% confidence interval = 0.39, 5.88; P = 0.73). No statistical difference existed between the preva lence of abnormalities on MRI in those with isolated GDD and GDD with additional symptoms, although the small numbers of participants with isolated GDD risks a type II statistical error. Further studies are warranted to determ ine the usefulness of MRI in children with isolated GDD.