Author: bsnrtrainees

The 2019 BSNR Trainee Days took place in St Anne’s College, Oxford on the 24^th & 25^th June 2019, and this year the topics were neuro-oncology on the first day and ENT and skull base on the second. Below is a summary to give a flavour of the topics covered on the days and a few learning points and references that I took away. As ever, any glaring errors are mine rather than the lecturers!

Day 1 – Neuro-Oncology

Pieter Pretorius kicked off the day with a discussion of the implications of the 2016 WHO classification of brain tumours for neuroradiologists, highlighting the key areas where we need to develop our reporting and looking at where there is evidence to align radiological and molecular findings (for example here). He discussed the problem of referring to ‘low-grade’ gliomas as a group, suggesting this is an unhelpful term as it is usually used in the setting of grade 2 diffuse astrocytomas, which are difficult to distinguish from grade 3 tumours. The areas of imaging where we can potentially add prognostic information were also highlighted (see here).

Adam Waldman gave two complementary talks, first taking a guided tour through brain regions and which tumours to expect in different anatomical locations, and in the second talk looking into molecular stratification and drilling down into how radiologists can add value in the era of molecular diagnosis. The relative contribution of perfusion imaging and spectroscopic imaging (including the future application of 2-HG spectroscopy) were discussed, along with potential pitfalls, and also the issues of treatment response and pseudoprogression and the danger of relying on contrast enhancement to assess response with new treatment agents such as the anti-angiogenics.

fMRI and DTI physics are a challenging topic even in a room full of radiology trainees, but Stephen Wastling addressed them in a clear and practical way , highlighting how they are used in preoperative planning and how an awareness of the underlying mechanisms allows the user to account for other pathologies that might affect the imaging results. Samantha Mills took this into the operating theatre, showing how the Walton Centre makes use of its intraoperative MRI and the challenges of running an intraoperative MRI service, as well as sharing her clinical experience of using fMRI and DTI.

Glioma imaging across Europe is very heterogeneous in its application (as seen here), and Gerry Thompson looked at how to make sure your centre is using its advanced imaging appropriately, starting with a thorough understanding of the techniques and software used in MR perfusion and spectroscopy. He stressed the importance of not accepting outputs from scanner software without interrogating the data yourself and understanding where the potential problems could arise. In his tutorial he recommended the ASFNR guidance on performing DSC-perfusion MRI as a starting point for standardised physiological imaging and a way to evaluate your own institutional processes.

The afternoon workshops took us through a fascinating selection of difficult and interesting cases, from tumour follow-up and post-treatment changes with Robin Joseph, tumour mimics with Priya Bhatnagar, perfusion applications with Gerry Thompson, pediatric tumours with Rob Dineen, and some representative cases from the neuro-oncology MDT with Samantha Mills.

Overall it was an excellent and informative day; the common themes emerging were the importance of having a fundamental understanding of the advanced imaging techniques and where they can be useful before applying them, as they are a useful adjunct rather than a cure-all, and that radiomics/radiogenomics are in their early stages but will have more and more of an impact on the traditional imaging approach to brain tumours so we need to stay up to date and on our toes!

Day 2 – ENT & Skull Base

The second day began with a clinically orientated, practical lecture from Fintan Sheerin on infective pathologies of the neck. His rules and myths were particularly useful: for example, that the origin and current site of an infection are more important than where it is going (and hence the ‘danger space’ is not a particularly useful concept), and that infection rarely enters the tonsil from outside so if involved is usually the point of origin.

Reena Dwivedi pointed out that the majority of our scans as neuroradiologists included the nasopharynx and as such it was crucial for us to have an appreciation of common and significant pathology even for (perhaps especially for) those who do not report head and neck imaging, and her talk gave an excellent overview of the pathologies to suspect and how to investigate them.

Ata Siddiqui gave the first of his two talks on the orbit, highlighting important and unusual pathologies and focusing on optic neuropathy, with useful clinical suggestions for differentiating demyelinating aetiologies (see here for differences between multiple sclerosis and neuromyelitis optica, here for those between NMO and MOG, and here for a protocol for the investigation of optic neuritis) and touching on imaging for papilloedema (see here for a suggested review).

Sinuses were next up and Jagrit Shah gave an overview of how to approach sinus reporting systematically, using the CLOSE checklist system as a structure (outlined here) to ensure that surgically important anatomical variants are flagged up preoperatively.

The importance of understanding the surgical perspective also ran through Gitta Madani’s excellent talk on the temporal bone, including surgical blind spots (for example the sinus tympani in the middle ear), and relevant variants (for example limited access to the oval window by a variant facial nerve canal) as well as important pathology to identify.

Rounding up the lectures was Ata Siddiqui talking on paediatric head and neck, covering a wide range of paediatric pathology. Particular highlights were the clear discussion of vascular anomalies which can be difficult to classify appropriately (good resources are the ISSVA classification document here and a concise commentary here) and the spectrum of branchial cleft anomalies (see a useful review here).

The tutorials included general head and neck and neuroradiology interesting cases from Reena Dwivedi and Fintan Sheerin, an introduction to the skull base MDT from Jagrit Shah and skull base surgeon Sanjeeva Jeyaratna, temporal bone lesions with Gitta Madani and orbital and sinonasal cases with Ata Siddiqui.

Common themes emerging from the second day were the importance of having a good understanding of important head and neck imaging pathologies even if this is not an area you would normally report as a neuroradiologist, and how crucial a thorough understanding of the surgical perspective and a good working relationship with the surgeons is to head and neck imaging.

Overall, the two days were a fantastic educational experience, and thanks go to Gerardine Quaghebeur and the BSNR trainee day working group who organised the event as well as all of the excellent speakers and tutors on the days. I look forward to seeing you at the next trainee day in Cardiff in October!

 

 

Welcome to the November journal round-up! This month we are lucky to have Jonathon Buwanabala, an interventional neuroradiology trainee in Cambridge, writing for us on his most important articles in intervention.

New frontier: A distal thrombectomy option

The current evidence for thrombectomy devices is limited to LVO in proximal anterior circulation stroke. Pushing standard thrombectomy devices deeper into the cerebral tree has a potential for complications. Crockett et al. in JNIS have published an interesting interventional option around this challenge with the use of microcatheters and a ‘micro-ADAPT’ technique to treat distal vessel occlusions. In this early review the recanalisation rate was 79% and most of these cases were upgraded to a higher TICI grade. This pathology is often seen in tandem with a large vessel occlusion or as a secondary embolism after treatment of a proximal occlusion.

Novel treatment – Embolisation in chronic subdural haemorrhage

Link et al. in Neurosurgery discuss a novel technique of managing chronic subdural hematoma with middle meningeal artery embolisation. Benefit was seen in a mixture of patient groups and with these promising initial results a larger trial has been suggested. A further benefit of this treatment method is that the interventionalist can look for an anomalous ophthalmic artery from the MMA prior to treatment. Would your centre engage in recruitment for a larger trial?

Why do low TICIs happen?

TICI (Thrombolysis in Cerebral Infarction score) 3 is always the goal in endovascular treatment of stroke, however, we often find ourselves with faced with less satisfactory angiographic results. Leischner et al. in JNIS have published an article analysing cases with lower TICI grades. They establish the main causes as broadly fitting into 1) failing to reach the thrombus, 2) reached but impassable thrombus and 3) incomplete recanalisation despite device deployment. Additionally, there is discussion around what strategies might facilitate a higher recanalisation rate such as, direct carotid artery puncture in cases of tortuous carotid anatomy and stenting and/or Intra-arterial infusions enface with the clot in irretrievable cases.

Case of the month

The global #Neurorad Twittersphere has a thriving online presence, which serves as a portal for collaboration with a strong focus on education and training. Stemming from this are a subset of neurointerventionalists who are sharing their cases on Twitter with some very interesting discussions being had about differences in local practices/patient selection, equipment choice and procedural planning amongst other things. Naturally being evidence-based practitioners a paper was published by Dmytriw et al. in JNIS. clarifying that cases published on Twitter don’t reflect the day to day complication rates seen in interventional neuroradiology; however, they can be very useful educational resources. A good example is the case below.

Case courtesy of Dr Stanimir Sirakov, St Ivan Rilski University Hospital, Bulgaria:

https://twitter.com/SirakovStanimir/status/1062424757029736448?s=03

Why not tweet your cases using the hashtag #INRCOTM so that they are all searchable to other INR trainees? We will select the most interesting one as our interventional case of the month in the next blog.

 

 

 

Welcome to the October journal round-up!

Emergency – Postoperative appearances can often be confusing and Chughtai et al. have written a useful article covering the normal and pathological findings following craniotomy and craniectomy, from infection and haemorrhage to extracranial tamponade and trephine syndrome.

Susceptibility weighted imaging has become a routine sequence in brain imaging, and is crucial in determining patterns of haemorrhage allowing diagnosis as well as non-haemorrhagic causes. A review by Skalski et al. in Emergency Radiology takes us through the main diagnoses that can be made on SWI.

Neoplastic – Tumour follow-up is a minefield as we are still learning the radiological correlates of treatment and pseudoprogression remains a difficult diagnosis to make confidently. Kessler & Bhatt in Insights into Imaging provide an overview of post-treatment imaging in neuro-oncology, looking at the utility of advanced imaging and the plethora of direct treatment effects, particularly radiation-induced, as well as covering commonly used assessment criteria for treatment response.

As we have touched on many times before in the blog, genetics in neuro-oncology is increasingly becoming an area in which radiologists must have a better understanding, and paediatric brain tumours are no exception. A review in Radiographics by AlRayahi et al. is therefore timely, discussing the key molecular mechanisms to understand for context in paediatric brain tumours and their relationship to imaging and treatment.

Metabolic – Imaging for central diabetes insipidus is relatively common, but knowledge of the underlying physiology and anatomy and the variety of potential causes is essential for interpreting imaging in this context. Adams et al. in Neuroradiology discuss these topics and also address optimal imaging protocols in a helpful pictorial review covering the relevant pathology.

Infection – In Practical Neurology, Delgado-Garcia et al. have published an interesting review of neurocysticercosis and its mimics, summarising their institutional cohort in Mexico and previous case reports. The tables provide a concise breakdown of the different stages of the disease (and the parasite life cycle) and consider imaging mimics for each stage and important discriminating features.

Intervention – A multisociety meeting was held at the World Federation of Interventional and Therapeutic Neuroradiology to discuss the topic of organisation and training for mechanical thrombectomy, and the resulting recommendations published in JNIS provide a framework for thrombectomy practice informed by available evidence and the experience of experts across the globe. These are by necessity rather general at the moment but can form a baseline for informing practice in future.

Spine – Spinal haematoma is uncommon but imperative not to miss, and Pierce et al. provide an excellent review of the relevant anatomy, imaging features of haematoma in different spinal compartments and important differential diagnoses.

Paediatric – The utility of DWI stretches beyond infarct and infection, and this is particularly true in pediatric imaging, as a welcome review by Carney et al. in Clinical Radiology points out. They widen the potential uses of DWI to include metabolic, inflammatory, congenital and neoplastic pathologies as well as to spot abnormalities outside the brain itself, illustrated with characteristic imaging examples.

That’s all for this month – as ever let me know if there is anything you’ve found useful that we’ve missed and see you next month!

The Trainee Day preceding the joint BSNR/ISNR annual meeting in Dublin was held at the Beaumont Hospital, and, drawing on the excellent interventional service based there, was focused on neurovascular pathology. Below is a summary of the day with some of the learning points I took away and useful references – any errors are mine rather than the speakers!

The day began with a comprehensive overview of current evidence in stroke imaging by Dr Grant Mair, specifically looking at the recent trials and the appropriate imaging modalities for patient selection in thrombectomy. Advanced imaging techniques were discussed, particularly 4D CTA (useful, for example, in differentiating occlusion and high grade stenosis) and CT perfusion; although there does not seem to be a clear consensus on quantification or which of the many perfusion parameters to consider, practically cerebral blood volume (CBV) is the most useful. He also highlighted the recent article from the HERMES collaborators looking at baseline imaging characteristics and response to thrombectomy, particularly the fact that infarcts with all ASPECTS values may have response to intervention. Another key point for me was the potential value of dual energy CT to better visualise early ischaemic change and to remove contrast to differentiate between contrast staining and haemorrhage, which can be difficult in practice.

Next was Dr Tilak Das on parenchymal haemorrhage, again taking a usefully practical approach to the investigation and causes of haemorrhage. He highlighted the prognostic utility of measuring haematoma volume (with >30cc a cutoff over which patients are unlikely to be functionally independent, albeit based on data from the 1990s), and imaging features to predict haematoma expansion (margin irregularity, fluid-fluid levels, heterogeneity and the spot sign – for more on this see the April journal round-up). Regarding causes, in young children the vast majority will have a vascular malformation, and in adults a secondary cause is more likely to be found with lobar haemorrhage (particularly with intraventricular involvement). Specific causes discussed included AVMs (for which the Spetzler-Martin classification provides a useful checklist of things to report), cerebral amyloid angiopathy, infarcts, and tumours (which should be considered if the haematoma has an irregular margin, too much oedema or too much enhancement).

Dr Stavros Stivaros covered paediatric vascular disease, highlighting the difference in mechanism and outcome in vascular injury between preterm and term infants, and within term infants whether the injury is prolonged, with preservation of metabolically more active areas, or acute and profound in which they are affected early. The CASCADE criteria are a useful framework for thinking about the potential causes of paediatric stroke. Infection is an important cause of stroke in older children, particularly HSV or VZV, and initial vascular imaging may be normal but CSF PCR should be performed in children with embolic infarcts, and perfusion imaging is often essential to identify occult hypoperfusion in the setting of vasculopathy. The importance of identifying features suggesting underlying genetic disorders was also stressed.

The workshops built on the themes of the lectures, covering thrombectomy case selection, patterns of subarachnoid haemorrhage and investigation pathways, vasculopathies and traumatic injuries with a great selection of interesting cases.

Dr Seamus Looby talked about subarachnoid haemorrhage, discussing the need to screen certain groups with MRA (for example those with two or more first degree relatives with SAH and adults with polycystic kidney disease) and the sensitivity of imaging compared to CSF analysis (xanthochromia is present from 6 hours to 2-3 weeks). Appropriate imaging strategies depend on the distribution of blood (a useful reference with flowcharts is available here). Vasospasm occurs typically between 3 and 14 days of SAH, peaking at 7-10 days, and only 40-70% of patients will have imaging evidence, while conversely those with imaging evidence may not be symptomatic. When considering monitoring of unruptured aneurysms, surveillance should be balanced with the available evidence on risk of rupture.

In the final lecture, Dr Sarah Power reviewed vasculopathies, dividing them into inflammatory and non-inflammatory causes. Useful classifications include the 2012 Chapel Hill consensus classification (available here as part of an excellent wider review of CNS vasculitis) which uses the size of the vessel but also considers associated pathologies (i.e. systemic disease or iatrogenic causes). As neuroradiologists we need to be confident with the entity of primary angiitis of the central nervous system (a helpful imaging study of PACNS is available here). In imaging terms it is useful to consider the brain, the vessel lumen and the vessel wall in turn to come to a diagnosis. Information regarding cause can be inferred from the size, timing and distribution of infarcts, the presence of haemorrhage, white matter lesions and presence of enhancement (particularly around infarcts, perivascular or leptomeningeal). Luminal abnormalities on angiographic imaging demonstrate the extent and distribution of the vasculopathy and vessel wall imaging can differentiate vasculitis and atherosclerotic disease (see the March journal round-up for more on VWI).

Overall it was a very educational day and our thanks go to Dr Power, the organiser, and all of the speakers and workshop leaders for their work. The next trainee days are currently being planned for spring 2019 – hope to see you there!

 

Welcome to the August journal round-up. A quick reminder that there are still a few places left at time of writing for the BSNR trainee day before the annual meeting, on 11^th October – info and book your place here: https://www.neuroradiology2018.com/spr-teaching-day.

Tumour – Pseudoprogression remains a difficult clinical and radiological issue, and in an article in JMRI this month, Thust et al. provide a pragmatic overview, reviewing the available evidence and diagnostic criteria and examining the role of conventional, advanced and novel imaging techniques in tackling the issue.

In European Radiology this month, Li et al. examined a cohort of central neurocytomas and other intraventricular tumours in order to determine the most useful diagnostic imaging features; they found six: the most sensitive was the ‘broad base attachment’ sign and then the ‘soap bubble’ and ‘peripheral cyst’ signs, and the most specific were the ‘scalloping sign’, ‘fluid-fluid level’ sign and the ‘gemstone’ sign.

Vascular & Intervention – The utility of vessel wall imaging is still being determined in clinical practice but with a new study in AJNR by Larsen et al. this takes a step forward, with useful radiopathological correlation. They looked at patients who had vessel wall imaging before clipping of unruptured MCA aneurysms which were then examined post exclusion, and the wall enhancement tended to correlate with pathological evidence of inflammation, which may be a step towards predicting rupture.

A systematic review in JNNP by Kaesmacher et al. set out to determine if the received wisdom about the adequacy of a TICI2b outcome in mechanical thrombectomy is supported by evidence. After examining 14 studies including 2379 patients found that TICI3 perfusions are associated with superior outcome and safety profile than TICI2b, so this should perhaps be targeted in mechanical thrombectomy.

White matter disease – Subcortical U fibres are often invoked but seem less frequently understood, so a focused review in Neurographics by Riley et al. is welcome. Covering the anatomy and normal myelination pattern before delving into pathology, this provides a useful approach to white matter disease based on the involvement of U-fibres.

Unfortunately, ethanol and methanol poisoning are a relatively common occurrence and a second useful Neurographics review by Yedavalli et al. looks at the diverse acute and chronic manifestations of both.

Distinguishing tumefactive demyelination from genuine tumour is a frequent problem in neuro-oncology MDTs and a systematic review and meta-analysis by Suh et al. in AJNR demonstrates the value of conventional MRI and the need for ongoing work on advanced imaging. Useful conventional MRI signs included open rim enhancement, a T2 hypointense rim, mild or absent mass effect, or mild perilesional oedema.

Spine ­– Mauch et al. in AJNR examine another common clinical conundrum, distinguishing between benign osteoporotic and malignant vertebral compression fractures. They tailor their review to the pitfalls of different imaging techniques and examine the most useful imaging features and the role of advanced imaging.

Paediatric – The mucopolysaccharidoses are a complex group of disorders with mostly skeletal manifestations, and a review in Pediatric Radiology by Nicolas-Jilwan and AlSayed collects the relevant neuroimaging manifestations (the summary table of clinical and imaging findings in the different conditions is particularly helpful).

Also in Pediatric Radiology, D’Arco et al. provide an excellent pictorial review of paediatric posterior fossa tumours with reference to the 2016 WHO classification, with a flow chart that is invaluable for identifying tumours based on their imaging features.

That’s all for this month. Hope to see many of you at BSNR in a few weeks!

 

Welcome to the July journal round-up! A reminder that registration for the BSNR annual meeting and SpR trainee day remains open, visit www.neuroradiology2018.com to register. 

Intervention – The management of tandem occlusions, where an intracranial arterial occlusion coincides with an extracranial internal carotid artery occlusion, is controversial and can be challenging. In JNIS this month, Wilson et al. designed a systematic review and meta-analysis to address this, comparing extracranial and intracranial first approaches as well as stenting versus angioplasty. They found, having included 33 studies, that there was no difference in outcome between these groups and just under half of patients with tandem occlusions had good neurological outcomes.

Paraspinal arteriovenous fistula are a complex entity and multiple classification systems have been proposed. Wendl et al. in BJR review the literature and their own case series in order to develop a clinically useful system, and the article functions as a review of the different subtypes and available treatment options.

Neoplastic – An interesting case series in Neurology Clinical Practice by Dhamija et al. reviews their centre’s experience of neuroradiological findings in Cowden syndrome, stressing that it is not only Lhermitte-Duclos that is found in these patients, and suggesting broadening of the diagnostic criteria to include more neuroimaging abnormalities.

Inflammatory/Infective – With the ongoing concern about gadolinium administration, particularly in those undergoing multiple repeat scans, Karimian-Jazi et al.’s investigation of the utility of gadolinium in multiple sclerosis follow-up is timely. They found that if T2 lesion load is stable, the chance of their being an enhancing lesion is extremely low and not administering gadolinium could therefore be considered.

Tyler in NEJM has written a concise review of acute viral encephalitis, which is clinically focussed and provides valuable context when reporting MRI in these cases.

Degenerative – Nuclear imaging has an expanding role in the evaluation of dementia, and the review of PET/CT in dementia by Zukotynski et al. in AJR is a helpful overview, discussing the findings in specific pathologies but also the role for newer tracers and future directions for clinical evaluation.

Spine – Brucellar spondylodiscitis is a rare entity but clinically important because it mimics tuberculous infection. Liu et al. in Academic Radiology looked at their own case series to determine if their were useful distinguishing features on imaging, finding that the use of fat-saturated T2 imaging showed uniform increased signal intensity across the whole vertebra in brucellar infection compared to heterogeneous partial involvement in tuberculosis.

Kunam et al. in Radiographics have produced an excellent review of incomplete spinal cord syndromes, including an accessible overview of relevant anatomy and the imaging findings of the specific syndromes.

And in Insights into Imaging, Moghaddam and Bhatt provide a framework for a systematic approach to evaluating intramedullary cord lesions, focusing on the location, length and enhancement pattern of the lesion in order to correctly classify it.

Paediatric – A consensus statement in Pediatric Radiology by Choudhary et al. aims to provide guidance for both doctors and the courts on the correct interpretation of findings in the setting of abusive head trauma. This is compulsory reading for anyone involved in these cases, giving a practical overview of the process of diagnosis and the many pitfalls involved, and the sources of misunderstanding or misinformation that cause problems in court.

Interpretation of neuroimaging in the context of haematopoietic stem cell transplantation can be difficult due to the myriad potential neurological complications. Bonardi et al.’s review in Radiographics provides clinical context, outlines the categories of complication and highlights the importance of understanding the treatment timeline and the patient’s current immune status as this changes the imaging appearances.

That’s all for this month, let us know if there’s anything you think we’ve missed and see you next month!

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 11^th 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.

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.

Neoplastic – Barisano 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!

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!

 

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…