April Journal Round-Up

Welcome to the April journal round-up! After the vascular-heavy blog last month, we’ve got a much more even mix this week with a lot of interesting articles to cover. As ever, let me know if you think anything is missing!

Emergency – Although the CTA spot sign is validated for predicting expansion of intracranial haemorrhage, given that many presenting with a haemorrhage do not get a CTA, prediction on the basis of non contrast CT alone would be useful. Morotti et al. aim to do just this in Stroke, developing a scoring system which they validate in two trial cohorts. Their 5-point scoring system has three components: the ‘blend sign’, intrahaematoma hypodensity, and time from onset, and showed good correlation with haematoma expansion.

In Emergency Radiology this month, Bhattacharya and Pendarkhar present a pictorial review of neurovascular emergencies in pregnancy and the puerperium, which acts as a helpful aide-memoire when assessing patients presenting in these periods.

Tumour – As previously discussed on this blog (see the July and November Tumour sections), it will become increasingly important to become familiar with imaging phenotypes of specific gene mutations in the assessment of brain tumours after the 2016 WHO classification. Lasocki et al. have conducted a useful study examining the specific imaging manifestations of 1p/19q codeletion grade II/III gliomas on structural MRI. They found that the presentation of >50% T2/FLAIR mismatch had the highest sensitivity and specificity for non-codeleted tumours, and calcification for codeleted tumours. Whilst these features were not universal, they suggest that in situations where genotyping is not possible they could be used as a surrogate marker.

Infection/Inflammatory – Two articles this month tackle the often tricky clinicoradiological issue of progressive multifocal leukoencephalopathy (PML). A review in Lancet Neurology by Morgan et al. goes into detail about what we have learned about the pathophysiology of the disease, the role of MRI in diagnosis in monitoring and future directions and challenges, providing a broad clinical context for the specific role of imaging. Wattjes et al. in JNNP focus on the imaging findings in the more inflammatory form of PML seen in natalizumab treatment and the phenotypic overlaps with PML-IRIS.

CJD can be a difficult diagnosis to make due to its rarity in the general neurology clinic, and Rudge et al. examine a cohort of patients from a specialist prion clinic in order to determine the most useful diagnostic features, confirming the importance of acquiring DWI and cautioning the interpretation of CSF 14-3-3 protein which is helpful but nonspecific.

Spine – The differential for transverse myelitis is wide, and Chee et al. help to narrow it with a study looking at the specific imaging features pointing towards an aquaporin-4 positive neuromyelitis optica related transverse myelitis, suggesting a scoring system including cervicomedullary involvement, high expansion ratio and bright spotty lesions.

Uei et al. in Spine tackled the bane of the on-call neuroradiologist, the cord compression MRI, and find that the degree of radiological cord compression (as measured by the epidural spinal cord compression scale) does not correlate well with the degree of clinical paralysis. They suggest that the degree of anterolateral or circumferential compression is more important than the ESCC grade, particularly in the cervical spine, in predicting rapidly progressive paralysis. This is an interesting paper, providing a surgical perspective for a very frequent radiological presentation.

Paediatric – With the ongoing concern regarding the retention of gadolinium, Dunger et al. present a timely and important study in Pediatric Radiology examining the utility of contrast administration in children with normal pre-contrast MRI brain examination (in over 3000 patients), finding that there are rarely any additional relevant findings from post contrast studies. This provides a powerful argument for restricting the use of gadolinium in this context.

Sanz et al. in BJR examined a cohort of paediatric patients with septic shock to determine the imaging findings in this clinical context, showing that ischaemia and cerebritis were the most common imaging presentations and suggesting that injury via vascular mechanisms is likely to be more clinically important than direct infective spread to the brain.

Miscellaneous – The incidental pituitary lesion is a common imaging finding but guidance as to appropriate imaging follow-up is often lacking. The ACR Incidental Findings committee have taken on this issue and in an article in JACR by Hoang et al. provide useful flowcharts for incidental lesions seen on CT or MRI and PET – which might be useful to have stuck on the reporting room wall!

Finally, a welcome intervention to all those disappointed by the suboptimal neuroanatomy knowledge displayed by the antagonist in the most recent James Bond film, SPECTRE, as Dr Currie recommends himself to would-be Bond villains as a consulting neuroradiologist in a fantastic letter to Neuroradiology.

That’s all for this week – but I’d be particularly keen to hear about any other fictional neuroanatomy blunders that Dr Currie could sort out for us…