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OBJECTIVE: Abnormalities on peri-ictal diffusion-weighted magnetic resonance imaging (DWI-PMAs) are well-established for patients with status epilepticus (SE), but knowledge on patterns of DWI-PMAs and their prognostic impact is sparse. METHODS: This systematic review and individual participant data meta-analysis included observational studies reporting adult patients with first-time non-anoxic SE with DWI-PMAs. Authors reporting ≥ 10 patients were invited to share standardized individual participant data. RESULTS: We identified 161 studies reporting on 531 individual patients (average age 52 years) who could be classified into one of six different DWI-PMA patterns. Of all reported DWI-PMAs, 94.3% involved either cortex or hippocampus. Comparing DWI-PMA patterns, pure hippocampal DWI-PMAs (n = 54, 10.2%) were associated with younger age, known epilepsy, and low mortality. Additional thalamic involvement (n = 132, 26.1%) was linked to temporal DWI-PMAs and was an independent predictor of poor functional outcome. Independent of the patterns, bilateral DWI-PMAs and involvement of more than four cortical lobes were associated with worse outcome. Cerebellar involvement (n = 36, 6.8%) was associated with non-temporal lobe DWI-PMAs, coma, and independently associated with poor functional outcome. Lateralization of DWI-PMAs and epileptic discharges showed substantial agreement (Cohen's kappa 0.69, p < 0.001). Lateralized or generalized period discharges were associated with thalamic involvement (54.2%) and were less frequent in patients with pure cortical (33.0%) or hippocampal DWI-PMAs (21.4%, p < 0.001). INTERPRETATION: DWI-PMA due to SE originates from the cortex and/or hippocampus depending on age and etiology. Additional involvement of the thalamus and cerebellum is associated with worse outcomes, as are more widespread DWI-PMA. Lateralized or generalized periodic discharges are associated with thalamic involvement.