cerebellar hypoplasia
description
this is the absence or underdevelopment of all or part of the cerebellum. it therefore includes total agenesis or hypoplasia, in addition to isolated aplasia of the vermis or cerebellar hemispheres. as the cerebellum and vermis are fully formed by fifteen weeks gestation, prenatal diagnosis of cerebellar anomalies can usually be made from then.
diagnosis
direct measurement of the cerebellum relates to gestational age so that cerebellar hypoplasia can be excluded by reference to standard measurement charts. vermian hypoplasia or aplasia is commonly associated with enlargement of the cisterna magna by a herniated cyst of the fourth ventricle (dandy-walker malformation), where splaying of the cerebellar hemispheres will be observed.
differential diagnosis
the findings of cerebellar dysgenesis should prompt search for other intracranial anomalies of which dandy-walker or its variants are the most common.
sonographic features
absence or diminished size of all or part of cerebellum.
associated with dandy-walker malformation.
associated syndromes
- acrocallosal syndrome
- agonadism-cns anomalies
- alcohol
- arima: cerebro-oculo-hepatorenal
- barth: cerebro-cerebellar
- bertini: myoclonic epilepsy-macular degeneration
- cerebro-ocular-muscular
- chromosomal abnormalities
- craniosynostosis-alopecia
- crome: cataracts-nephropathy
- cytomegalovirus
- dyskeratosis congenita
- egger-joubert-boltshauser
- endosteal sclerosis-cerebellar hypoplasia
- facial hemangioma-cerebrovascular anomalies
- fernhoff: abnormal facies
- frontonasal dysplasia
- frontonasal dysplasia-like
- g
- gillespie: aniridia-ataxia
- herrick: multisystem atrophy
- histidinemia
- hurst: leptomeningeal angiomatosis-cleft lip
- hutterite dysequilibrium
- isotretinoin
- joubert
- kbg
- kid (keratitis-ichthyosis-deafness)
- leber amaurosis, congenital
- lethal mesomelic dwarfism
- lethal multiple pterygium
- lethal osteopetrosis
- l’hermitte: oxycephaly-retardation
- majewski: short ribbed polydactyly
- meckel-gruber
- microcephaly-aminoaciduria
- mýbius
- mžller: cerebral malformation-hypertrichosis-fingers
- nephronophthisis-retinopathy
- neu-laxova
- neuroepithelial cysts-corpus callosum
- nonketotic hyperglycinemia
- norman-urich: pontoneocerebellar hypoplasia
- oculo-renal-cerebellar
- organoid nevus
- orofaciodigital type iii
- osteosclerosis-meningeal abnormalities
- oto-palato-digital ii
- pancytopenia-microcephaly
- pena-shokeir phenotype
- pfeiffer: oligodactyly-abnormal facies
- port wine nevus
- refsum, infantile
- retinal coloboma-congenital ataxia
- retinopathy-aplastic anemia
- spastic paraplegia-cerebellar hypoplasia
- stoll: cerebellar hypoplasia-endosteal sclerosis
- tapetoretinal degeneration-cerebellar hypoplasia
- thrombocytopenia-absent radius
- thyrocerebrorenal
- troost: cerebral calcifications
- v¼radi: ofd-like
- velo-cardio-facial
- vici: immunodeficiency-cataracts
- winter-wigglesworth: cerebro-renal
- x-linked dandy walker-basal ganglia
- x-linked laterality
- young: agenesis of the corpus callosum
- young: x-linked congenital ataxia
references
- rees aej, bates a, clarke h cerebellar hypoplasia in the second trimester associated with microcephaly at birth ultrasound obstet gynecol 5: 206-208
- keogan mt, deatkine ab, hertzberg bs cerebellar vermian defects: antenatal sonographic appearance and clinical significance j ultrasound med 13: 607-611
- wilson me, lindsay dj, levi cs, ackerman te, gordon wl us case of the day radiographics 14: 678-681
- estroff ja, scott mr, benacerraf br dandy-walker variant: prenatal sonographic features and clinical outcome radiology 185: 755-758
- hill lm, martin jg, fries j, hixson j the role of the transcerebellar view in the detection of fetal central nervous system anomaly am j obstet gynecol 164: 1220-1224