Accuracy of radiologists, nonradiologists, and laypeople for identifying children with cerebral cortical atrophy from "Mercator map" curved reconstructions of MRIs of the brain.

BACKGROUND: Using text reports to communicate bilateral, symmetric, and zonal cortical brain atrophy in children with term hypoxic ischemic injury (HII) to parents and legal professionals contesting compensation rights can be difficult. Using standard cross-sectional images for explaining bilateral, regional brain imaging to laypeople is also challenging. A single flattened image of the brain surface, much like a map of the earth is derived from a globe, can be generated from curved reconstruction of magnetic resonance imaging (MRI) scans, i.e., a Mercator map. Laypeople's ability to identify abnormal "Mercator brain maps," without prior training, requires evaluation before use in nonmedical settings. AIM: To determine the sensitivity and specificity of laypeople in detecting abnormal pediatric Mercator flat-earth maps of the brain, without prior training. METHODS AND MATERIALS: 10 Mercator brain maps were provided to 111 participants individually. The maps comprised 5 HII, 1 cortical dysplasia, and 4 normal cases. Participants were required to identify the abnormal scans. Sensitivity and specificity overall and for participants' subgroups were calculated. RESULTS: Overall sensitivity and specificity were 67% and 80%, respectively. General radiologists (n = 12) had sensitivity and specificity of 91.2% and 94.6%, respectively. Laypeople (n = 54) had a sensitivity of 67% and specificity of 80%. CONCLUSION: The high specificity and sensitivity of radiologists validated the technique for distinguishing abnormal scans, regarding cortical pathology. High specificity of laypeople for identifying abnormal brains using Mercator maps indicates that this is a viable communication tool for demonstrating cortical MRI abnormalities of HII in children to laypersons.

Cortical ischaemic patterns in term partial-prolonged hypoxic-ischaemic injury-the inter-arterial watershed demonstrated through atrophy, ulegyria and signal change on delayed MRI scans in children with cerebral palsy.

The inter-arterial watershed zone in neonates is a geographic area without discernible anatomic boundaries and difficult to demarcate and usually not featured in atlases. Schematics currently used to depict the areas are not based on any prior anatomic mapping, compared to adults.Magnetic resonance imaging (MRI) of neonates in the acute to subacute phase with suspected hypoxic-ischaemic injury (HII) can demonstrate signal abnormality and restricted diffusion in the cortical and subcortical parenchyma of the watershed regions.In the chronic stage of partial-prolonged hypoxic-ischaemic injury, atrophy and ulegyria can make the watershed zone more conspicuous as a region. Our aim is to use images extracted from a sizable medicolegal database (approximately 2000 cases), of delayed MRI scans in children with cerebral palsy, to demonstrate the watershed region.To achieve this, we have selected cases diagnosed on imaging as having sustained a term pattern of partial-prolonged HII affecting the hemispheric cortex, based on the presence of bilateral, symmetric atrophy with ulegyria. From these, we have identified those patients demonstrating injury along the whole watershed continuum as well as those demonstrating selective anterior or posterior watershed predominant injury for demonstration.Recognition of this zone is essential for diagnosing partial-prolonged hypoxic-ischaemic injury sustained in term neonates. The images presented in this pictorial review provide a template for identifying the cortical watershed distribution when there is milder regional (anterior, parasagittal, peri-Sylvian and posterior) watershed injury and for more severe injury where multiple regions are injured in combination or as a continuum.

Technical report: 3D printing of the brain for use as a visual-aid tool to communicate MR imaging features of hypoxic ischaemic injury at term with non-physicians.

3D printing has been used in several medical applications. There are no reports however of 3D printing of the brain in children for demonstrating pathology to non-medical professionals such as lawyers. We printed 3D models of the paediatric brain from volumetric MRI in cases of severe and moderate hypoxic ischaemic injury as well as a normal age matched control, as follows: MRI DICOM data was converted to NifTI (Neuroimaging Informatics Technology Initiative) format; segmentation of the brain into CSF, grey, and white matter was performed; the segmented data was converted to STL format and printed on a commercially available scanner. The characteristic volume loss and surface features of hypoxic ischaemic injury are visible in these models, which could be of value in the communication of the nature and severity of such an insult in a court setting as they can be handled and viewed from up close.

Curved reformat of the paediatric brain MRI into a 'flat-earth map' - standardised method for demonstrating cortical surface atrophy resulting from hypoxic-ischaemic encephalopathy.

Hypoxic-ischaemic encephalopathy is optimally imaged with brain MRI in the neonatal period. However neuroimaging is often also performed later in childhood (e.g., when parents seek compensation in cases of alleged birth asphyxia). We describe a standardised technique for creating two curved reconstructions of the cortical surface to show the characteristic surface changes of hypoxic-ischaemic encephalopathy in children imaged after the neonatal period. The technique was applied for 10 cases of hypoxic-ischaemic encephalopathy and also for age-matched healthy children to assess the visibility of characteristic features of hypoxic-ischaemic encephalopathy. In the abnormal brains, fissural or sulcal widening was seen in all cases and ulegyria was identifiable in 7/10. These images could be used as a visual aid for communicating MRI findings to clinicians and other interested parties.