raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:97252

Mega-cisterna magna

Type
Morphological anomaly
Group
Disorder
Status
active

A rare, non-syndromic, posterior fossa malformation characterized by a cisterna magna that measures above 15 mm in length, 5 mm in height and 20 mm in width (or greater than 10 mm in fetuses) associated with a normal cerebellar vermis and absence of hydrocephalus. The majority of patients are asymptomatic; however, variable neurodevelopmental outcomes, including delayed speech and language development, motor development delay, visiospatial perception difficulties, and attention problems, has been observed in some patients.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enMega-cisterna magna
frMéga-cisterna magnaPoche arachnoïdienne de la cisterna magna
deMegacisterna magna
esMegacisterna magna
itMega cisterna magna
nlMega-cisterna magna
ptMegacisterna magna
plMega-cisterna magna
csMega cisterna magna
ukMega-cisterna magna
zh巨大枕大池
trMega-sisterna magna

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
ICD-10Q07.8NTBTattributedvalidated
MONDO0019953Evalidated
UMLSC3164501Evalidated

E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.

3

Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (1):

No children.

4

Genes

0 direct

Orphanet records no gene directly on this code.

5

Prevalence and incidence

0 records

No prevalence record in this release.

6

HPO phenotypes

Orphanet has no HPO annotation for this code in this release.

7

Sources for this card