Lesson 1Perfusion imaging interpretation: core vs penumbra, Tmax, CBF, CBV thresholds and pitfallsThis section explains CT and MR perfusion interpretation, differentiating core from penumbra using CBF, CBV, and Tmax maps, reviewing standard numeric thresholds, vendor variations, artefacts, and clinical pitfalls that may affect treatment choices.
Physiologic basis of core and penumbraTmax, CBF, and CBV map interpretationCommon numeric thresholds and caveatsArtifacts, motion, and truncation errorsChronic infarct and leukoaraiosis pitfallsLesson 2Guidelines and decision thresholds: major society recommendations for imaging selection and treatment windowsThis section summarises key guideline recommendations for acute stroke imaging, covering time windows for IV thrombolysis and thrombectomy, imaging selection beyond standard windows, and applying decision thresholds in everyday practice.
Key AHA/ASA and ESO imaging guidanceImaging criteria for IV thrombolysisImaging criteria for thrombectomyLate-window and wake-up stroke imagingReconciling guidelines with local practiceLesson 3Communication with stroke team: phrasing for thrombolysis and thrombectomy eligibility, recommended next imaging and monitoringThis section emphasises concise, effective communication with the stroke team, with standard phrasing for thrombolysis and thrombectomy eligibility, statements on uncertainty, suggested next imaging, and advice on monitoring and repeat scans.
Key elements of the stroke phone reportPhrasing eligibility for IV thrombolysisPhrasing eligibility for thrombectomyRecommending next imaging stepsDocumenting uncertainty and follow-upLesson 4MRI protocols for hyperacute stroke: DWI, ADC, FLAIR, SWI, TOF/MRA, perfusion MRI parametersThis section covers MRI protocol setup for hyperacute stroke, detailing DWI and ADC for core infarct, FLAIR for onset timing, SWI for haemorrhage and thrombus, TOF/MRA for vessels, and perfusion MRI parameters for urgent decisions.
Optimizing DWI and ADC for ischemic coreFLAIR mismatch and stroke onset estimationSWI for microbleeds and susceptibility vessel signTOF and contrast MRA for vessel imagingPerfusion MRI: sequence choice and timingLesson 5Reporting structure for stroke code: critical findings, side and vascular territory, estimated core/penumbra, time-sensitive recommendationsThis section outlines a structured report for stroke code activation, highlighting clear details on haemorrhage, ischaemic core and penumbra, occlusion site, side and vascular territory, plus urgent recommendations for thrombolysis, thrombectomy, and follow-up imaging.
Standardized report headings and sequenceDocumenting hemorrhage and ischemic coreSide, vascular territory, and ASPECTS scoringStating thrombectomy and lysis eligibilityTime-stamped, actionable recommendationsLesson 6CT protocols: slice thickness, reconstruction, contrast timing for CTA, coverage for perfusionThis section reviews non-contrast CT, CTA, and CT perfusion protocols for acute stroke, focusing on slice thickness, reconstruction settings, contrast timing, and perfusion coverage to optimise speed, radiation safety, and diagnostic quality.
Noncontrast CT slice thickness and kernelsCTA acquisition timing and contrast bolusCT perfusion coverage and slab selectionRadiation dose, ASIR, and artifact reductionMotion management and patient positioningLesson 7Selecting emergency imaging: noncontrast CT, CT angiography, CT perfusion and MRI alternativesThis section guides selection of emergency imaging options, comparing non-contrast CT, CTA, CT perfusion, and MRI based on symptom onset time, patient condition, contraindications, and available resources for efficient, evidence-based workflows.
Baseline noncontrast CT indicationsWhen to add CTA in the first scanRole of CT perfusion in triageWhen MRI is preferred or essentialBuilding site-specific imaging algorithmsLesson 8Vascular occlusion assessment: site of occlusion, collateral status, thrombus length and clot burden scoreThis section details systematic evaluation of vascular occlusion, identifying site, clot length, collateral flow, and clot burden scores on CTA and MRA, and their impact on thrombectomy suitability and patient outcomes.
Identifying proximal versus distal occlusionsMeasuring thrombus length on CTACollateral grading systems and scoringClot burden score and prognosisImaging predictors of recanalizationLesson 9False negatives and mimics: seizure, migraine, hypoglycemia, posterior fossa limitations and strategies to reduce errorsThis section covers false negatives and stroke mimics like seizures, migraines, hypoglycaemia, functional issues, and posterior fossa strokes, with imaging strategies and protocol tweaks to minimise errors in urgent settings.
Common clinical and imaging stroke mimicsSeizure and postictal imaging appearancesMigraine aura and perfusion abnormalitiesPosterior fossa stroke CT limitationsStrategies to reduce false negativesLesson 10Key acute imaging signs: early ischemic changes, hyperdense vessel sign, territorial infarction patternsThis section discusses essential CT and MRI signs of acute ischaemia, such as early parenchymal changes, hyperdense vessel sign, loss of grey-white differentiation, sulcal effacement, and territorial infarct patterns linked to vascular areas.
Early ischemic CT signs and ASPECTS useHyperdense artery sign and variantsLoss of gray–white differentiation patternsTerritorial infarct patterns by vascular territoryPosterior circulation and lacunar stroke signs
