Rare diseases · Sign or symptom
Dandy-Walker malformation
HP:0001305
What it means
A congenital brain malformation typically characterized by incomplete formation of the cerebellar vermis, dilation of the fourth ventricle, and enlargement of the posterior fossa. In layman's terms, Dandy Walker malformation is a cyst in the cerebellum (typically symmetrical) that is involved with the fourth ventricle. This may interfere with the ability to drain cerebrospinal fluid from the brain, resulting in hydrocephalus. Dandy Walker cysts are formed during early embryonic development, while the brain forms. The cyst in the cerebellum typically has several blood vessels running through it connecting to the brain, thereby prohibiting surgical removal.
Rare diseases that can present with this62
Very common80–99%
10- 3C syndrome
- Aase-Smith syndrome type 1
- Cervical hypertrichosis-peripheral neuropathy syndrome
- Craniosynostosis-Dandy-Walker malformation-hydrocephalus syndrome
- Dandy-Walker malformation-postaxial polydactyly syndrome
- Facial dysmorphism-macrocephaly-myopia-Dandy-Walker malformation syndrome
- Isolated Dandy-Walker malformation
- Mosaic variegated aneuploidy syndrome
- NPHP3-related Meckel-like syndrome
- Spinal muscular atrophy-Dandy-Walker malformation-cataracts syndrome
Common30–79%
11- Acrocallosal syndrome
- Autosomal recessive cutis laxa type 2, classic type
- Cerebello-oculo-facio-genital syndrome
- Craniofacial dysplasia-short stature-ectodermal anomalies-intellectual disability syndrome
- MEND syndrome
- Neu-Laxova syndrome
- Orofaciodigital syndrome type 14
- PHACE syndrome
- Walker-Warburg syndrome
- Wrinkly skin syndrome
- X-linked female restricted facial dysmorphism-short stature-choanal atresia-intellectual disability
The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Also called: Dandy-walker anomaly · Dandy-Walker cyst
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Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.