Synthetic cases. These are fictional teaching vignettes, model-generated for testing clinical-reasoning systems. No real patients are described on these pages.
The vignette — bank Case 07, verbatim
Sorry to wake you. We have an 80-year-old female, last seen well 14 hours ago. Found on her kitchen floor. Prestroke mRS was 0. Her NIHSS is 21, dense left hemiplegia and neglect. Imaging performed was CT, CTA, and perfusion. CTA shows a right proximal internal carotid artery occlusion. CT perfusion shows a large area of severely depressed cerebral blood flow, under thirty percent of normal, measuring approximately 90 millilitres in the right MCA territory. The area of delayed perfusion is only slightly larger, around 105 millilitres. No thrombolysis was given due to the prolonged timeframe. Vitals are currently stable.
Why this one is hard
Five years ago this page would have been short: a 90 mL core was a closed door. Six randomised trials and their individual-patient meta-analysis reopened it — benefit across the large-core stratum, mortality lower with treatment, haemorrhage cost real but paid — and her core sits well under the 150 mL mark beyond which the estimates stop being interpretable. On tissue alone, she is inside the new evidence.
The clock and the mismatch are where it tightens. Fourteen hours approaches the far edge of what the trials enrolled, and the same evidence base, read along its time axis, shows the absolute benefit thinning as the hours accumulate. Her perfusion profile is the second squeeze: 90 mL of core inside 105 mL of hypoperfusion is a mismatch ratio close to 1.2 — the neighbourhood where a meta-analysis of the perfusion-requiring trials found benefit in intermediate mismatch and could not find it in low. She was fully independent yesterday, her severity is exactly what the trials asked for, and two of the three numbers that describe her sit at the thin end of their own evidence.
What makes the case hard is that nothing here is outside the trials — everything is at their edge, simultaneously. The evidence does not refuse her; it thins around her, on two axes at once, and the decision has to be made where the curves are flattest.
Literature anchors
- Sarraj A, et al. (ATLAS, individual-patient meta-analysis of the six large-core trials). Lancet 2026. doi:10.1016/S0140-6736(26)00876-7.
- Sarraj A, et al. (SELECT2). N Engl J Med 2023. doi:10.1056/NEJMoa2214403.
Break the demo — send a case
For stroke physicians and vascular neurologists only. This is not a route for personal medical questions; if you are a patient or a relative, do not use this address. The demo does not run anonymously, and it is not a clinical service. Every case is reviewed and approved by the administrator before it runs; responses may take several days. Never use this for a live clinical decision — for acute stroke, follow your local pathway.
Your case must contain no images and no patient-identifying data, and it must be retrospective — not an active patient awaiting a decision. A case may appear on this site anonymously, as a constructed teaching case; you are named only if you ask to be.