Riisfeldt Neurology Education

Diagnostic reasoning 101: Generating a differential diagnosis in medicine & neurology

CORRECTIONS: I probably should have emphasised that the anterior horn cell/lower motor neuron cell body sits in the ventral horn of the spinal cord, with its axon then projecting through the nerve root, plexus, peripheral nerve and ultimately down to the neuromuscular junction. The anterior horn cell diseases/motor neuronopathies are therefore encompassed by the anatomical approach laid forth specifically for neurological conditions towards the end of the episode, but for practical clinical purposes it would be sensible to consider the 'anterior horn cell/lower motor neuron cell body' as its own separate part of the nervous system and giving it its own 'row' in the table, as a reminder to consider these conditions! Also, I refer to the 'mnemonic' incorrectly as an 'acronym' a number of times (it's a sentence, not a single word!). Welcome 2026! The first episode of the new year goes back to absolute fundamentals, discussing the foundations of diagnostic reasoning and how to generate a differential diagnosis in both medicine as a whole and in neurology, falling within our clinical methods series. We begin by discussing systems 1 vs. systems 2 thinking, along with examples provided for each and when each system is appropriate, before moving onto the details of systems 2 thinking, focusing on the aetiological/pathophysiological categories of disease, functional anatomy, and how to marry these together to generate comprehensive differential diagnoses. The episode includes very my coveted, patented (not really!), never-shared-publicly-before mnemonic for a very special surgical sieve. We then discuss how these are applied to medicine and specifically to neurology, focussing on each part of the neuraxis/central nervous system (CNS) and peripheral nervous system (PNS), along with focussing on anatomical patterns (e.g. unilateral vs. bilateral, symmetry, upper vs. lower limbs, motor vs. sensory vs. sensorimotor, whether any ocular, bulbar or pulmonary involvement) and consideration of single vs. multiple lesion patterns to answer the age-old “where is the lesion?” question, as well as considering the tempo of symptom onset (hyperacute, acute, subacute or chronic) to strongly hint answers at the “what is the lesion?” question, to arrive at a provisional diagnosis and sensible investigation and initial management plan. This episode is perfect for medical students and junior doctors, and more senior audience members should also derive value. #medicaleducation #meded #medicine #neurology #doctor #rneurologyeducation

SGLT2 inhibitors and reduced risk of Parkinson’s disease and dementia: Journal club

This episode continues our run of journal club episodes, this time looking at whether SGLT2 inhibitors used for type 2 diabetes mellitus have any associated reduction in dementia (such as Alzheimer’s disease and vascular dementia) and Parkinson’s disease, therefore falling into these respective series as well. The content of this episode is best suited for more senior audience members (neurologists and neurology trainees), although all audience members (including medical students) will derive benefit from the way it teaches how to dissect a journal article, demonstrating the process involved in this critical evaluation and ultimately teaching how to decide in what ways a journal article applies to your daily clinical practice.#medicaleducation #diabetes #parkinsonsdisease #dementia #neurology #rneurologyeducation

Dopamine uptake scan (DAT SPECT; DaTscan) for Parkinson's disease/primary extrapyramidal syndromes

This instalment brings another journal club episode, this time in the Parkinson’s disease and movement disorders series, focussing on the diagnostic accuracy of dopamine uptake scans (DAT SPECT; DaTscan) for Parkinson’s disease and the other primary extrapyramidal disorders/Parkinson’s plus syndromes (progressive supranuclear palsy, PSP; multiple system atrophy, MSA; corticobasal degeneration, CBD), and distinguishing these from other neurodegenerative conditions which may manifest with Parkinsonian features, and from other non-neurodegenerative conditions such as essential tremor, dystonic tremor, drug-induced Parkinsonism and vascular Parkinsonism. The episode also provides an example of critically evaluating a journal article and determining how it should be applied in daily practice, an essential and transferable skill across all of clinical medicine. This is a more advanced episode, best suited for neurology trainees and neurologists, although other audience members should also find it valuable.#medicaleducation #doctor #parkinsonsdisease #journalclub #rneurologyeducation

Tenecteplase for stroke to 24 hrs: TRACE-III study journal club

We’re thrilled to present our first journal club episode, focusing on tenecteplase for ischaemic stroke in the 4.5-24 hour time window in patients with large vessel occlusions (LVOs) in whom mechanical thrombectomy is not an available option (the TRACE-III study, published in the New England Journal of Medicine; NEJM in 2024). This is a landmark study extending the thrombolysis timing window beyond 9 hours for the first time, although with a number of caveats as discussed in the episode. This episode, in addition to teaching you about the evolving landscape of hyperacute therapy options in stroke, teaches you how to critically evaluate a medical journal article, and how to then apply the journal article to your clinical practice, and determine in what ways (if any) that the article is practice changing. This is a more advanced episode, better suited to neurology trainees and neurologists, although more junior audience members will also find it valuable through its global significance in extending the thrombolysis window in places where mechanical thrombectomy is not available, and through its providing a step-by-step worked example in regard to how to critically evaluate a neurology article, an essential and highly transferable skill across clinical medicine as a whole.Correction: At various times when discussing the results section, I refer to the ‘placebo group’ (as a force of habit, apologies!) as opposed to correctly saying the ‘control group’ in this case, given that this was an open-label study at the time of randomisation (not placebo-controlled) and then later blinded at the time of outcome measurement and statistical analysis, as was discussed in the episode.

How to run a stroke call/code stroke & decision-making re. thrombolysis/thrombectomy eligibility

Hope you’re ready for an important one! In this next instalment in the stroke & cerebrovascular diseases series we discuss how to effectively run a stroke call/code stroke, focussing on establishing the time last seen well (or midpoint of sleep), the baseline function (modified Rankin scale; mRS), stroke deficits (National Institutes of Health Stroke Scale; NIHSS), relevant comorbidities, & anticoagulants & antiplatelets. This then allows us to quickly and effectively make a diagnosis and a management decision in regard to whether the patient is eligible for thrombolysis &/or mechanical thrombectomy (endovascular clot retrieval; ECR). As always, the episode is presented in an accessible, story-based way with anecdotal experiences being used to supplement a discussion of the literature/evidence-base, in order to make the content memorable and practical, so that you ace your next stroke call/code stroke & save your patient a few hundred million neurons in the process! This episode is appropriate for all audience members from medical students through to neurologists.#medicaleducation #meded #doctor #stroke #rneurologyeducation