Moyamoya disease (MMD) is the condition at the heart of ANNI's founding story. It is a rare cerebrovascular disorder characterised by progressive occlusion of the internal carotid arteries and the development of abnormal collateral vessels at the base of the brain. While it is most studied in East Asia, its presence in African populations is almost certainly under-documented.
Section 9.5 · The Evidence
Statistics on Moyamoya disease.
| Indicator | Statistic | Source |
|---|---|---|
| Cognitive impairment in MMD patients (meta-analysis, 17 studies) | 54.59% | Toh et al., JAD 2024 |
| Most common cognitive deficit in MMD | Executive dysfunction | Toh et al., 2024; Frontiers Hum Neurosci 2024 |
| High misdiagnosis rate reported in | Europe (likely higher in Africa) | European MMD White Paper, 2023 |
| MMD-associated epilepsy risk factors | High mRS, early seizures, atrophy | Predictive Factors for Epilepsy in MMD, PubMed |
| MMD research concentration | East Asia (Africa underrepresented) | MedComm Review, 2025 |
| Genetic markers identified for MMD | RNF213, ACTA2, DIAPH1, HLA | He et al., MedComm 2025 |
Expert Analysis
What the evidence tells us.
A comprehensive 2025 review of advances in Moyamoya disease notes that most epidemiological research has been conducted in East Asia, with very little data from African populations. This gap is critical: the clinical presentation, genetic profile, and available treatment options may differ substantially for African patients, and the extreme scarcity of neuroimaging and specialist care means MMD in Africa is almost certainly underdiagnosed and misdiagnosed.
— He et al., MedComm, 2025
The first European guidelines for Moyamoya disease, published in 2023, acknowledge that a high misdiagnosis rate has been observed in Europe. If misdiagnosis is common in well-resourced European health systems, the rate in African settings — where MRI access is limited, neurologists are scarce, and awareness is near-zero — is likely far higher.
— European MMD Guidelines, 2023; European MMD White Paper, 2023
ANNI's Unique Position
Why ANNI is uniquely positioned on Moyamoya disease.
One of Few African-Led Voices on MMD
ANNI is one of the very few African-led organisations explicitly addressing Moyamoya disease in research and awareness.
Lived Expertise from the Founder
As a Moyamoya survivor, the Founder brings lived experience and credibility to a condition largely invisible in African neurology discourse.
African MMD Patient Registry
ANNI is developing a Moyamoya patient registry to document African cases and support future research collaboration.
“The condition that nearly ended a PhD journey is now the condition driving a continental mission for visibility and care.”