acalvaria
Findings
No curated finding names acalvaria yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Acalvaria is a rare malformation defined as missing scalp and flat bones over an area of the cranial vault. The size of the affected area is variable. In rare cases, acalvaria involves the whole of the dome-like superior portion of the cranium comprising the frontal, parietal, and occipital bones. Dura mater and associated muscles are absent in the affected area but the central nervous system is usually unaffected, although some neuropathological abnormality is often present (e.g. holoprosencephaly or gyration anomalies). Skull base and facial bones are normal.
Definition from the Mondo Disease Ontology (MONDO:0019795), read 2026-09-29. CC BY 4.0.
Features
14 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Abnormal skull morphologyHPOHP:0000929
- Very frequent (80% to 99% of cases)
- Aplasia/Hypoplasia of the cerebellumHPOHP:0007360
- Very frequent (80% to 99% of cases)
- Abnormality of neuronal migrationHPOHP:0002269
- Frequent (30% to 79% of cases)
- Calvarial skull defectHPOHP:0001362
- Frequent (30% to 79% of cases)
- Postaxial hand polydactylyHPOHP:0001162
- Frequent (30% to 79% of cases)
- Abnormal cardiovascular system morphologyHPOHP:0030680
- Occasional (5% to 29% of cases)
Show the remaining 2
- Spina bifidaHPOHP:0002414
- Occasional (5% to 29% of cases)
- TalipesHPOHP:0001883
- Occasional (5% to 29% of cases)
Where it sits
Other names
1 name
Resolves to: acalvaria
- Also called
- Acrania