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The aim of this blog is to provide a resource for neuroradiology trainees (and any other interested readers), and collect useful information from other sources in one helpful package. To this end, I will post a monthly round-up of articles which I think are of interest to neuroradiology trainees, and hopefully in future expand to cover other useful resources, potentially including (but not restricted to!):

  • Course and conference reviews/updates
  • Blogs on research/publications undertaken by neuroradiology trainees by the researchers themselves
  • Advice on fellowship/consultant posts and applications

This will only be useful with your collaboration, so please do get in touch if you would like to contribute any of the above, or have any other ideas you would like to explore. I would also be interested to know which articles/resources you find useful in training, particularly any I miss in the monthly round-up, as I would like to build up a repository of useful articles to eventually complement the new curriculum.

Do get in touch via the comments below or on bsnrtrainee@gmail.com.

Tom (BSNR Trainee Rep)

 

June Journal Round-Up

Welcome to the June journal round-up! A reminder before we start that registration for the BSNR Annual Meeting is open, with the Trainee day preceding it on the 11th October which will have a diagnostic neurovascular focus. And also for UK trainees, if you haven’t already filled out the BSNR trainee survey please do! It’s available here.

Emergency – Spontaneous intracranial haemorrhage is a common presentation and the differential diagnosis is wide; Kranz et al. have written a helpful overview identifying key features to report and how to narrow the differential. Their mnemonic ‘BLEED’ for the key reporting features in ICH (how Big, Location, Edema, Extension, Displacement) is also useful, particularly in teaching junior registrars what to include.

Vascular – There were plenty of useful neurovascular articles published last month, and it seems appropriate to start with Lin et al.’s comprehensive discussion of neurovascular imaging techniques in Neurosurgery, which concisely covers the logic behind using different vascular imaging techniques for different pathologies and examines their particular uses in clinical scenarios.

Adam et al. in Insights into Imaging consider stroke mimics, covering the major differential diagnoses and how to use different MRI sequences in order to diagnose these appropriately. Their flowchart in figure 1 is a useful reference for specific imaging features for the numerous mimics.

Now that thrombectomy is being widely used for proximal large vessel occlusions, the obvious next step which many are taking is to chase the more distal occlusions and Grossberg et al. in Stroke provide some data to support this approach. In their cohort of 69 patients, there was only a slightly lower mRS 0-2 outcome compared with their larger proximal thrombectomy cohort (32% vs 44%) and a similar mortality, and a good reperfusion rate of 83% (TICI 2b-3), suggesting this may be a safe and effective treatment option although larger cohorts are required.

Cerebral venous sinus thrombosis is thought to be underdiagnosed and is often missed initially, so Dytriw et al.’s review in Neuroradiology is a good opportunity to review the clinical, pathophysiological and imaging features of this condition, outlining the utility and drawbacks of different imaging modalities and the role of radiologists in treatment and follow-up.

Neoplastic – Glioma imaging varies widely between different centres and there is little guidance on best practice in this area. Thust et al. performed a survey to evaluate the practice across Europe and provide focused guidance for setting up glioma imaging protocols, and is essential reading for trainees because of the justification for each sequence and the specific problem each of them addresses.

Inflammatory – The search for a biomarker to significantly enhance the specificity of diagnostic criteria for MS continues, and a further addition to the potential candidates is the use of the so-called ‘dark rim’ sign using a double inversion recovery technique. Tillema et al. found that the use of this sign, which was seen in 35% of lesions in patients with MS and 1% of lesions in those without, increase the specificity of the 2010 McDonald criteria (from 17% without to 78% with at least 1 rim lesion and 97% with two or more). Although the pathophysiology of the sign remains to be determined it may be a useful addition, although necessitates incorporating an additional sequence into diagnostic MS studies.

Degenerative – In Radiology this month Enkirch et al. presented their scoring system for assessment of the entorhinal cortex in Alzheimer’s disease, known as the ERICA score, which had increased diagnostic accuracy when compared to the medial temporal atrophy score and had a high interrater reliability. This is a easy to apply visual scoring system and may potentially become the dominant rating scale in future.

Cerebellar ataxias are rare but important entities and there are a wide variety of inherited syndromes. Heidelberg et al. present a useful pictorial review of the major differential diagnoses and key imaging features to differentiate them.

Miscellaneous – Finally, for those needing any justification in ditching their tie, Luddecke et al. demonstrated that wearing a necktie reduces your cerebral blood flow. Having said this, it was with a ‘tightened’ necktie and did not reduce it below the normal range, so you probably don’t need to worry about tie-related strokes just yet.

That’s all for this month, enjoy the summer and see you next time.

May Journal Round-Up

Welcome to the May journal round-up. Before we start, registration to the joint BSNR/ISNR annual meeting in Dublin has just opened and the deadline for abstract submission is 31/7/18, so get those abstracts in and I hope to see you there!

Trauma – We have previously looked at the difficult issue of blunt cerebrovascular injury (see the March journal round-up), and two articles this month explore this topic further. In JNS, Grandhi et al. retrospectively analysed their BCVI patients who had undergone screening according to the Denver criteria, and importantly followed up positive CTA with DSA, finding that there was a very high false-positive rate particularly for grade 1 injuries (47.9%). They suggest the use of DSA after a positive CTA to minimise unnecessary antithrombotic therapy.

The available criteria for BCVI are highly geared towards sensitivity, and therefore are likely to be inappropriate in paediatric populations. Herbert et al. in JNS Paediatrics devised a new set of criteria, the McGovern score, to select patients for angiographic imaging based on their cohort of blunt trauma patients, which adapts the Utah score by adding mechanism of injury. They compared available scoring systems including the Denver, Memphis, EAST and Utah scores and found significant misclassifications using these scores.

Vascular – Perimesencephalic haemorrhage is a form of subarachnoid haemorrhage with a more benign clinical course, and the workup for these patients can be rationalised based on this knowledge. Mensing et al. in Stroke conducted a systematic review of perimesencephalic haemorrhage, and among useful clinical factors the radiological finding was that a single CTA is the preferred diagnostic approach over multiple DSAs or subsequent MRI, as only 4% will be due to aneurysm. They also found evidence to support the hypothesis that perimesencephalic haemorrhage is likely venous in origin.

The absence of contrast opacification in the extracranial ICA in the setting of ischaemic stroke can present a diagnostic dilemma, as the possibilities include occlusion, dissection or pseudo-occlusion. Kappelhof et al. used the MR CLEAN trial data to determine whether these could be distinguished on CTA, finding that this was possible with good sensitivity and specificity, using the finding of gradual contrast decay in the ICA above the carotid bulb in the absence of atherosclerotic findings and the presence of carotid T or large M1 occlusion to suggest pseudo-occlusion.

Intervention – Despite the profusion of evidence for mechanical thrombectomy in ischaemic stroke, there is little data on the effectiveness of thrombectomy in elderly populations, and Hilditch et al. in AJNR aimed to summarise what data exists in a systematic review. They found that although outcomes were inferior to those in younger patients, a significant benefit could be obtained using thrombectomy and suggest that age should not exclude patients from this treatment.

The Society for Neurointerventional Surgery released a report this month in JNIS on endovascular strategies for cerebral venous thrombosis, reviewing the risk factors, clinical and imaging findings and outcomes for CVT. They present an algorithm for treatment which includes endovascular treatment if there is clinical deterioration despite anticoagulation, if anticoagulation can’t be administered, if there is coma, deep CVT or intracranial haemorrhage. However, evidence is lacking as to the appropriate timing of endovascular treatment following anticoagulation and the specific technique to be used.

NeoplasticBarisano et al. provide a useful review of effects related to radiation surgery and radiotherapy for the treatment of brain and spinal tumours, covering pseudoprogression and radiation necrosis in detail and including the imaging features of multiple other complications such as leukoencephalopathy, myelopathy, atherosclerosis, and radiation induced cavernous malformations and tumours.

Inflammatory/Autoimmune – The intracranial findings of neuromyelitis optica spectrum disorders (NMOSD) have been increasingly recognised and Wang et al. have published a review in BJR summarising the characteristic intracranial findings within their own cohort, using the characteristic localisations to help to distinguish from other demyelinating disorders (with a table dedicated to differentiating from MS). This article works well in conjunction with the review in our January round-up.

Anti-NMDA receptor encephalitis can be difficult to diagnose as a result of its nonspecific brain MRI findings. Zhang et al. in AJNR examined a cohort of patients to assess the imaging findings and any association with 2 year clinical outcome, finding that while imaging is often normal, hippocampal abnormalities were the most common abnormal finding and were a predictor for poor prognosis at 2 years.

Degenerative – Ollivier et al. in Neurographics present an interesting review of imaging findings in atypical Parkinsonian syndromes, focusing on the clinical utility of advanced imaging techniques in this group of patients as well as summarising the structural MRI findings. They highlight the high rate of misdiagnosis due to overlapping clinical findings in these diseases, and knowledge of the relevant advanced imaging techniques is therefore likely to be crucial in investigation of these patients in future.

Spine – In Practical Neurology this month Mariano et al. have written a pragmatic approach to spine lesions, starting from clinical findings and presenting a number of useful algorithms to determine a specific cause. This review would be particularly useful for on-call and exam preparation, with concise clinical information and useful imaging and laboratory tests in an easy to read format.

The spectrum of developmental vertebral anomalies is wide and can be daunting, and it is helpfully demystified in a clear pictorial review by Chaturvedi et al. in Insights into Imaging, which starts with the relevant embryology and highlights malformations which may either mimic or be at increased risk for traumatic injury.

Paediatric Reddy et al. describe the imaging findings in organic acidemias and aminoacidopathies in a comprehensive review in Radiographics, highlighting the role for imaging in narrowing down the differential and guiding appropriate diagnostic workup and the differentiation of these inborn errors of metabolism from acute intracranial pathologies.

Miscellaneous – Two reviews published this month may be more head and neck in flavour but cover topics very important to neuroradiologists. The first, in Radiographics, presents the craniofacial manifestations of systemic disease, acting as a useful reference for those tricky incidental findings on head CTs. The second is a helpful review by Capobres et al. in Neurographics of the anatomy and pathology of the facial nerve.

That’s all for this month. If you’re a UK trainee, please look out for the trainee survey which will be sent out this month, and in particular your feedback on the blog and what you’d like to see included in the future. We’re also hoping to move to the main BSNR website as part of its update and redesign – watch this space!

BSNR Trainee Days – Summary and Highlights

After the success of previous BSNR trainee days attached to the annual meetings, this was the first of hopefully regular mid-year educational meetings, designed specifically for neuroradiology trainees to develop their knowledge coming towards consultant posts. The plan is for these to have rotating topic areas so that the breadth of neuroradiology will be covered over an approximately two-year period, corresponding to most fellowships.

The topics this year were two that trainees find notoriously tricky – paediatrics and spine – and the course took place in Newcastle at the Royal Victoria Infirmary. Below is a summary of the days to provide a flavour of the course, some learning points that I took away (would be great to hear any others from those attending!) and some key references. I apologise in advance for any butchery by paraphrasing of the excellent talks – any mistakes are mine!

Paediatric Neuroradiology

The day was opened in auspicious fashion with a talk on perinatal injury by Dipayan Mitra, which covered the role of cranial ultrasound in looking for germinal matrix haemorrhage and periventricular leukomalacia, the appropriate imaging strategy for neonatal encephalopathy (the BAPM imaging guidance, available here, recommends performing MRI at 5-14 days for optimal sensitivity and accuracy), and then focused on specific imaging findings in hypoxic ischaemic injury and the imaging sequelae of early damage in cerebral palsy (see Bax et al. 2006 for a useful review). He was followed by Dr Neil Stoodley who talked about his fascinating experience as a medicolegal expert, describing his role in interesting cases and how to get into this area as a radiologist (where the demand for paediatric neuroradiologists is high!) and how to balance it with clinical work.

We have often discussed the implications of the 2016 WHO Tumour Classification in this blog, and Dan Warren provided an excellent summary relating to paediatric tumours, covering many of the new and modified tumour classifications (a useful review in Radiographics is available here, and a specific review on diffuse midline gliomas here). The emphasis is now on molecular diagnosis which is likely to override histological diagnosis (see Schindler et al. on the prevalence of a particular mutation, BRAF V600F, in multiple histological tumour types). An interesting discussion following the talk focused on our role in light of these new guidelines – how far should we go in trying to nail a molecular diagnosis, and should we avoid the old ‘histological’ diagnoses, in our imaging report? Given the difficulties, the most useful approach was felt to be a descriptive report and focused MDT discussion.

Adam Thomas broke the first rule of neurogenetics club to tell us all about this interesting innovation, which brings together all those interested and involved in the diagnosis of paediatric neurogenetic disorders for twice yearly meetings to discuss interesting and difficult cases and share experience in this complex area. He highlighted the pitfalls of pattern recognition in this context, the potential genetic underpinnings for congenital malformations, and the importance of recognising specific features in order to direct gene panels for particular imaging phenotypes, as well as MDT discussion. Most importantly was keeping an open mind (and Google browser tab)! Some of the many useful references included a review of intracranial calcifications, one of neurodegeneration with brain iron accumulation and another of cortical malformations.

The afternoon small group tutorials provided an excellent opportunity to go through these and other areas in more detail with case-based teaching on non-accidental injury, epilepsy, posterior fossa malformations, infections, white matter disorders and neurometabolic disorders. There was too much to summarise here, but the RCR/RCPCH guidance on suspected physical abuse in children (available here) is mandatory reading for those involved in paediatric neuroradiology reporting.

The day finished with current co-Du Boulay Professor Daniel Birchall giving an intriguing talk on his ‘seven effective habits of consultant radiologists’, his tips for succeeding as a consultant interspersed with personal experience. An insightful and funny approach, it was a great way to finish the day and segue into the evening social activities.

Spinal Neuroradiology

The second day began with a lively discussion around Justin Nissen’s talk on what a spinal surgeon wants from radiologists – this was a great opportunity to see from the other side, and see some of the frustrations with radiology departments as well as where we can be useful. This was followed by a great overview of vascular pathology of the spine from David Minks, going through arteriovenous fistulae and malformations as well as aneurysms and ischaemic pathologies. This led nicely into Tilak Das’s presentation on spinal cord signal change, which provided an excellent framework for assessing focal cord signal abnormality, dividing into compressive and non compressive pathologies then further into inflammatory and non-inflammatory conditions and examining useful features in each group. The diagnostic criteria for acute transverse myelitis are worth reading and suggested reviews on differential diagnosis are available here, here and here.

Spinal trauma was next on the agenda, with the other co-Du Boulay Professor Stuart Currie presenting another useful framework for approaching spinal injury, considering the role of MRI for soft tissue and spinal injury, protocolling (MRI should be performed within 72 hours of injury to pick up oedema from ligamentous injury), stability according to the Denis classification and focal cord injuries. He also highlighted the blind spot of vascular injury, crucial to consider in spinal trauma.

David Butteriss then gave a very interesting lecture on a less well-studied topic, that of imaging and treatment in intracranial hypotension, outlining the imaging features not to miss to make the diagnosis (and avoid other harmful treatment) and the role of the interventional neuroradiologist in treating, with non targeted and targeted epidural blood patching and how to hunt down the leak using the imaging available.

The afternoon consisted of five further small group tutorials, covering tumours, dysraphisms (a helpful pictorial review is available here), infection, inflammatory conditions and trauma.

Overall, it was a fantastic and very educational two days. I would like to thank all of the faculty, and particularly all of the small group tutors whose interesting cases and interactive sessions I couldn’t do justice to here, and special thanks go to the organiser Priya Bhatnagar and her team in Newcastle who put a great course together. The next one will be in Dublin in October – I hope to see you there!

 

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…

March Journal Round-Up

Welcome to the March journal round-up!

Trauma – Blunt cerebrovascular injury presents a significant clinical and radiological problem, as it can be very difficult to detect but screening all patients risks overutilization of limited resources and potential overdiagnosis. Two articles this month tackle this issue – a concise review by Nagpal et al. in AJNR compares the available diagnostic criteria and grading scales, whilst Rutman et al. in Radiographics provide a more comprehensive pictorial review with a focus on explaining the underlying pathophysiology.

Another common pathology associated with blunt trauma, thoracolumbar spine injury, is the subject of a review by Bonfante et al. in Neurographics, who discuss the pathology and biomechanics of injury to this region, compare the available classification systems for the injuries and discuss the clinical utility of these systems. This is a useful reference for anyone reporting trauma studies.

Vascular Last month we included the ASNR’s guidance on vessel wall imaging. This month Pinho et al. in Neurographics give us a practical guide to vessel wall imaging, covering technical guidance on optimising imaging protocols and normal and abnormal findings. Potential expanded roles for vessel wall imaging are covered in two further articles this month – Dlamini et al. examine the application in paediatric stroke, and Lehman et al. in JNS review its use in aneurysm imaging (table 1 is an excellent reference guide to the findings in different types of aneurysm).

With the increasing use of T2* and susceptibility weighted imaging as well as higher field strengths, microhaemorrhages are being detected with greater frequency and it can be difficult to determine their significance. Haller et al. in Radiology provide a clear and relevant review that covers their detection, radiological-pathological correlation and their significance to multiple disease processes, as well as normal ageing.

Intervention – Two studies this month provided further evidence for the potential to extend the role of mechanical thrombectomy beyond large vessel occlusion within 6 hours of symptom onset. Following encouraging evidence from prospective trials, a retrospective study by Bucke et al. looked at the outcomes of patients with wake up strokes and strokes of uncertain daytime onset time in comparison to their ‘control’ cohort of within-time mechanical thrombectomy, and showed equivalence of the outcomes of the wake-up stroke cohort with controls and also a benefit related to the use of advanced imaging (i.e. MRI and CT perfusion). Haussen et al. used two prospective registries to compare mechanical thrombectomy with medical treatment alone in patients with mild symptoms (NIHSS </=5), and demonstrated a benefit in discharge NIHSS for mechanical thrombectomy.

Inflammatory – A review in Nature Reviews Neurology by Geraldes et al. should be required reading for neuroradiology trainees – the MAGNIMS study group reconvened to update their ‘red flags’, radiological signs that should alert the radiologist against a diagnosis of multiple sclerosis in the presence of white matter lesions. Given the prevalence of nonspecific white matter lesions in neuroradiology practice, this remains a frequent problem and their mnemonic ‘MIMICS’ is valuable to remember pointers towards other causes.

One aspect the authors of the above review touch upon is the central vein sign (veins running within the centre of white matter lesions), a presumed biomarker to distinguish MS from other causes of white matter lesions, which has been around for a while but has gained traction more recently with a publication by NAIMS on its evolution and use in 2016. An editorial in Neurology this week by Miller suggests this sign is ready for clinical use, expanding on an article by Cortese et al. demonstrating the sign’s value in distinguishing between MS and NMO spectrum disorders.

Paediatric – An article in AJR by Orru et al. provides a simple and effective approach to the assessment of the child with macrocephaly, with suggested imaging protocols and a pictorial review of common and less common causes.

Miscellaneous – Finally, a fascinating article by Reicher et al. in BJR examines the working practice of UK neuroradiologists and asks what we can learn from the aviation industry, specifically air traffic controllers who perform a qualitatively similar job, and cognitive science about how to improve it. The discrepancy between working practices as described by surveys conducted of the two professions and its potential impact on performance makes for thought-provoking reading!

That’s all for this month. As ever, let us know if there’s anything important we’ve missed, and have a good month!

February Journal Round-Up

Welcome to the February journal round-up!

Vascular – It’s a bit stroke-heavy this month, so a good place to start is the new American Heart Association stroke guidelines, published in Stroke. Although you may not want to read all 345 pages, the short sections on imaging and thrombectomy are a useful summary of the level of evidence for various factors that will affect us as radiologists, and are worth a read.

As a useful adjunct to this for neurointerventionalists, the Society of Neurointerventional Surgeons have also published updated guidance on mechanical thrombectomy, focusing on the evidence base for specific technical aspects of the procedure, in JNIS.

And for a more detailed discussion of the specific imaging modalities and their strengths and weaknesses in imaging evaluation of stroke, Smith and Rowland Hill have also provided a comprehensive review in the BJR.

Evaluation of carotid disease is clearly a crucial part of stroke imaging, and the relatively new technique of vessel wall imaging is an exciting prospect for this application. The ASNR have published a white paper with their recommendations for the use of vessel wall imaging, which provides an excellent context for where it can be most clinically useful.

Dural arteriovenous fistulae are notoriously difficult to diagnose, and in AJNR this month Copelan et al. describe a case series for a particular characteristic appearance of medullary oedema and enhancement in Cognard type V fistulae, noting the importance of recognising these features to avoid a long work-up for alternative pathologies.

Neoplastic – After the discussion of machine learning techniques in neuroradiology last month, the discussion in AJNR now focuses down on to its use in brain tumours in the new field of ‘radiomics’, noting the particular utility in neuro-oncology because of the potential to align imaging and genetic findings.

Inflammatory – Antibody-mediated encephalitides are increasingly understood to be much more common than we thought – indeed the most common, anti-NMDAR encephalitis, is more common than herpes encephalitis in young people. Yet this can seem like a bewildering array of random letters to the uninitiated! An excellent review in NEJM gives clinical context and highlights useful imaging findings to provide an introduction to these important pathologies.

Erdheim-Chester disease is a rare non-Langerhans cell histiocytosis, and Parks et al. in Neurology Clinical Practice use their relatively large cohort of 53 patients to examine the neuroradiological features of this disease.

Spine – The journal Neurosurgery have a useful (and open access) neuroradiology review series, and I have highlighted two articles from the series in this month’s blog. The first, by Chokshi et al., examines spinal neoplasms (both vertebral and cord) and also provides a very useful post-treatment section, particularly the imaging appearances of radiation-related complications.

Miscellaneous – Epilepsy imaging is an extremely challenging area for neuroradiology trainees, and there is a helpful review in Current Opinion in Neurology by Ruber et al. which focuses on accurate protocolling and the roles of advanced imaging for presurgical planning, as well as looking to potential future applications.

The second Neurosurgery neuroradiology review article, by Hudgins & Baugnon, concerns the skull base and provides an excellent overview and pictorial review of the anatomy and pathology of this complex region.

That’s all for this month. Hope you found it helpful, and do let us know if we’ve missed anything!

January Journal Round-Up

Welcome to the January journal round-up! Before we begin, we are pleased to announce the BSNR Trainee Study Days will be held in Newcastle on May 10-11th, with a focus on paediatric and spinal imaging and a mixture of lectures and workshops, modeled on the successful pre-annual meeting trainee days. Please email bsnr.traineeday@gmail.com to register your interest or for more information.

Vascular/Intervention – There is more support for extended (>6 hours) thrombectomy for proximal anterior circulation occlusions with the publication by Albers et al. in NEJM of results from the DEFUSE 3 trial. Using CT or MR perfusion and an automated imaging postprocessing system to select patients, they showed in an RCT that intervention following medical therapy up to 16 hours still conferred benefit.

Jansen et al. in Radiology went looking for other imaging correlates of response to intra-arterial therapy. They retrospectively used MR CLEAN trial data to examine whether a score based on the degree of cortical vein opacification (‘COVES’) on CT angiography could predict outcome, showing a higher mortality and no shift towards better functional outcome following intra-arterial treatment in those with a COVES (calculated looking at the superficial middle cerebral vein, vein of Labbe and the sphenoparietal sinus) of more than 0.

Neoplastic – In Practical Neurology, Larsen et al. give a timely overview of the role of imaging in the diagnosis, treatment planning and monitoring of low-grade glioma, in view of the trend towards more aggressive treatment and the changes in the 2016 WHO classification.

Leaning more towards treatment, Patibandla et al. have summarised the applications of stereotactic radiosurgery to help the neuroradiologist in the neuro-oncology MDT, with a pragmatic approach to the imaging aspects of common usages.

Inflammatory – It was all about multiple sclerosis (MS) this month, with the updated McDonald criteria published in the Lancet Neurology – key changes including the demonstration of CSF oligoclonal bands, the admissibility of symptomatic lesions in determination of dissemination in space or time, and the inclusion of cortical lesions with juxtacortical lesions. And just in the nick of time, as in the same journal a retrospective study by Filippi et al demonstrated equivalence of the 2010 McDonald criteria with the 2016 MAGNIMS criteria in predicting progression from clinically isolated syndrome, but highlighted possible areas for future development (at least one of which, the symptomatic lesions, has been incorporated into the new McDonald guidelines).

An appropriately timed overview of the current state of knowledge in MS is provided by Reich et al. in NEJM, and although the imaging aspect is limited this is a valuable and clear summary of our understanding of the complex pathophysiology of this still poorly understood disease.

A major set of differential diagnoses of MS are NMO (neuromyelitis optica)-spectrum disorders, and fortunately Garbugio Dutra et al. have published an excellent review of the history, diagnostic criteria, imaging features and differentials for these diseases.

Away from demyelination, IgG4-related disease is an increasingly diagnosed systemic disorder and its central and peripheral nervous system manifestations are outlined in a useful review by AbdelRazek et al. As it can mimic a number of other conditions, the detailed knowledge of the clinical context and systemic manifestations provided is crucial and the imaging features are also helpfully outlined.

Degenerative – Two interesting articles this month examined the diagnostic criteria for cerebral amyloid angiopathy (CAA), increasingly recognised and important in older populations (see the August round-up for more clinical context). In Stroke, Greenberg and Charidimou examine the evolution and validation of the most commonly used diagnostic criteria, the Boston criteria, and look at future directions for its development.

Conversely, Rodrigues et al. in Lancet Neurology set out to develop criteria to determine CAA as the cause for intracranial lobar haemorrhage on CT (the Edinburgh CT criteria), and found that two imaging findings, concurrent subarachnoid haemorrhage and ‘finger-like projections’ from parenchymal haemorrhage, in combination with APOE4 allele possession, had high specificity for CAA. The accompanying comment by Werring points out the need to compare these two sets of criteria and the potential strengths of both.

Paediatric – Neuroimaging is critical in the evaluation of paediatric traumatic brain injury, and a review by Mendoza et al. in Neurographics provides a useful summary of the spectrum of findings in accidental TBI, particularly paediatric-specific patterns of injury, and the emerging uses of advanced imaging in this context. In Emergency Radiology, Tang et al. examine the emergency vascular conditions seen in paediatric populations, with a focus on the importance of recognising stroke mimics.

Miscellaneous – Treatment effects are often a difficult or forgotten area and so a comprehensive review of treatment-related CNS abnormalities by Lincoln et al. in BJR is very welcome, covering the spectrum of side effects including PRES, IRIS, radiation and newer biologic agents and their specific complications.

And finally, we are constantly threatened with obliteration as radiologists by artificial intelligence and specifically deep learning. A review by Zaharchuk et al. in AJNR gives an in-depth explanation of the process by which deep learning can have useful applications in neuroradiology – but also provides hope that this will help rather than replace us!

That’s all for now, see you next month!