Cerebellar hypoplasia: Difference between revisions

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{{SI}}
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{{CMG}}; {{AE}}
{{CMG}}; {{AE}} {{Ahmadmuneeb}}


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{{SK}}  
== Overview ==
== Overview ==
Cerebellar hypoplasia is a condition in which cerebellar volume is significantly reduced but its shape remains intact. It occurs in multiple diseases and has various patterns on neuroimaging.  
[[Cerebellar hypoplasia]] is a condition in which cerebellar volume is significantly reduced but its shape remains intact. It occurs in multiple diseases and has various patterns on neuroimaging. Variety of [[prenatal]] insults have been associated with [[cerebellar hypoplasia]]. Diagnosis of [[cerebellar hypoplasia]] can be made [[prenatally]] as well as [[postnatally]]. [[Prognosis]] and treatment of [[cerebellar hypoplasia]] largely depend upon the underlying etiology.
 
== Historical Perspective ==
 
* [Disease name] was first discovered by [scientist name], a [nationality + occupation], in [year] during/following [event].
* In [year], [gene] mutations were first identified in the pathogenesis of [disease name].
* In [year], the first [discovery] was developed by [scientist] to treat/diagnose [disease name].


==Historical prespective==
There is no available data on historical perspective of [[cerebellar hypoplasia]].
== Classification ==
== Classification ==


* [Cerebellar hypoplasia] may be classified according to [extent of cerebellar involvement] into [four] subtypes<ref name="pmid24839100">{{cite journal |vauthors=Poretti A, Boltshauser E, Doherty D |title=Cerebellar hypoplasia: differential diagnosis and diagnostic approach |journal=Am J Med Genet C Semin Med Genet |volume=166C |issue=2 |pages=211–26 |date=June 2014 |pmid=24839100 |doi=10.1002/ajmg.c.31398 |url= |accessdate=2020-08-14}}</ref>:
* [[Cerebellar hypoplasia]] may be classified according to [extent of cerebellar involvement] into [four] subtypes<ref name="pmid24839100">{{cite journal |vauthors=Poretti A, Boltshauser E, Doherty D |title=Cerebellar hypoplasia: differential diagnosis and diagnostic approach |journal=Am J Med Genet C Semin Med Genet |volume=166C |issue=2 |pages=211–26 |date=June 2014 |pmid=24839100 |doi=10.1002/ajmg.c.31398 |url= |accessdate=2020-08-14}}</ref>:


:* [Unilateral cerebellar hypoplasia]
:* [[Unilateral cerebellar hypoplasia]]
:* [Cerebellar hypoplasia with predominant involvement of vermis]
:* [[Cerebellar hypoplasia with predominant involvement of vermis]]
:* [Global cerebellar hypoplasia involving both vermis and cerebellar hemispheres]
:* [[Global cerebellar hypoplasia involving both vermis and cerebellar hemispheres]]
:*[Hypoplasia involving pons along with cerebellum i.e pontocerebellar hypoplasia]
:*[[Hypoplasia involving pons along with cerebellum i.e pontocerebellar hypoplasia]]


== Pathophysiology ==
== Pathophysiology ==


* The pathogenesis of [cerebellar hypoplasia] is related to multiple disease processes. These include genetics mutations in certain genes involved in organization and maturation of fetal brain in pregnancy e.g Wnt family, En1 & 2, WDR 73 genes, and chromosomal abnormalities especially trisomy 9, 13, 18. Other disease processes associated with cerebellar hypoplasia include prenatal infections, prenatal exposure to teratogens, disruptive lesions, metabolic abnormalities..
* The pathogenesis of [[cerebellar hypoplasia]] involves faulty [[neuronal proliferation]] and migration during embryonic [[nervous system development]].<ref name="urlCerebellar hypoplasia | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program">{{cite web | url = https://rarediseases.info.nih.gov/diseases/1194/cerebellar-hypoplasia | title = Cerebellar hypoplasia &#124; Genetic and Rare Diseases Information Center (GARD) – an NCATS Program | author = | authorlink = | coauthors = | date = | format = | work = | publisher = | pages = | language = | archiveurl = | archivedate = | quote = | accessdate = 2020-08-15}}</ref> It is related to multiple disease processes,which may include genetics [[mutations]] in certain [[genes]] involved in organization and maturation of [[fetal brain]] e.g [[Wnt]] family as well as other [[genes]] like [[En1]] & 2, [[WDR 73]], and [[chromosomal abnormalities]] especially [[trisomy 9]],[[trisomy 13]],[[trisomy 18]].<ref name="pmid28205531">{{cite journal | vauthors = Subashini C, Dhanesh SB, Chen CM, Riya PA, Meera V, Divya TS, Kuruvilla R, Buttler K, James J | title = Wnt5a is a crucial regulator of neurogenesis during cerebellum development | journal = Scientific Reports | volume = 7 | issue = | pages = 42523 | date = February 2017 | pmid = 28205531 | pmc = 5311982 | doi = 10.1038/srep42523 | url = | issn = | accessdate = 2020-08-15}}</ref> <ref name="pmid2907320">{{cite journal | vauthors = Davis CA, Joyner AL | title = Expression patterns of the homeo box-containing genes En-1 and En-2 and the proto-oncogene int-1 diverge during mouse development | journal = Genes & Development | volume = 2 | issue = 12B | pages = 1736–44 | date = December 1988 | pmid = 2907320 | doi = 10.1101/gad.2.12b.1736 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid27983999">{{cite journal | vauthors = Jiang C, Gai N, Zou Y, Zheng Y, Ma R, Wei X, Liang D, Wu L | title = WDR73 missense mutation causes infantile onset intellectual disability and cerebellar hypoplasia in a consanguineous family | journal = Clinica Chimica Acta; International Journal of Clinical Chemistry | volume = 464 | issue = | pages = 24–29 | date = January 2017 | pmid = 27983999 | doi = 10.1016/j.cca.2016.10.029 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid18945628">{{cite journal | vauthors = Poretti A, Prayer D, Boltshauser E | title = Morphological spectrum of prenatal cerebellar disruptions | journal = European Journal of Paediatric Neurology : EJPN : Official Journal of the European Paediatric Neurology Society | volume = 13 | issue = 5 | pages = 397–407 | date = September 2009 | pmid = 18945628 | doi = 10.1016/j.ejpn.2008.09.001 | url = | issn = | accessdate = 2020-08-15}}</ref> Other disease processes associated with cerebellar hypoplasia include prenatal infections, prenatal exposure to teratogens, disruptive lesions, metabolic abnormalities..<ref name="pmid8147499">{{cite journal | vauthors = Barth PG | title = Pontocerebellar hypoplasias. An overview of a group of inherited neurodegenerative disorders with fetal onset | journal = Brain & Development | volume = 15 | issue = 6 | pages = 411–22 | date = 1993 | pmid = 8147499 | doi = 10.1016/0387-7604(93)90080-r | url = | issn = | accessdate = 2020-08-15}}</ref>
* On gross pathology, [feature1], [feature2], and [feature3] are characteristic findings of [disease name]..


== Causes ==
== Causes ==
[Cerebellar hypoplasia] may be caused by variety of etiologies listed below in the table.<ref name="pmid24839100">{{cite journal |vauthors=Poretti A, Boltshauser E, Doherty D |title=Cerebellar hypoplasia: differential diagnosis and diagnostic approach |journal=Am J Med Genet C Semin Med Genet |volume=166C |issue=2 |pages=211–26 |date=June 2014 |pmid=24839100 |doi=10.1002/ajmg.c.31398 |url= |accessdate=2020-08-14}}</ref>   
[[Cerebellar hypoplasia]] may be caused by variety of etiologies listed below in the table.<ref name="pmid24839100">{{cite journal |vauthors=Poretti A, Boltshauser E, Doherty D |title=Cerebellar hypoplasia: differential diagnosis and diagnostic approach |journal=Am J Med Genet C Semin Med Genet |volume=166C |issue=2 |pages=211–26 |date=June 2014 |pmid=24839100 |doi=10.1002/ajmg.c.31398 |url= |accessdate=2020-08-14}}</ref>   




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|'''Genetic disorders'''
|'''Genetic disorders'''
|gillepsie syndrome, beckwith-Wiedemann syndrome, ritscher shinzel syndrome, hoyeraal hreidarsson syndrome, charge syndrome,
|[[gillepsie syndrome]], [[beckwith-Wiedemann syndrome]], [[ritscher shinzel syndrome]], [[hoyeraal hreidarsson syndrome]], [[charge syndrome]],
endostel sclerosis, Delleman syndrome, epilepsy and permanent neonatal diabetes syndrome, neurofibromatosis type, pseudo torch syndrome,
[[endostel sclerosis]], [[Delleman syndrome]], [[epilepsy]] and [[permanent neonatal diabetes syndrome]], [[neurofibromatosis]], [[pseudo torch syndrome]],


velocardiofacial syndrome, cohen syndrome, pallister killian syndrome, cri du chat syndrome, senger syndrome, galloway mowat syndrome, CASK mutation, cerebellar agenesis.
[[velocardiofacial syndrome]], [[cohen syndrome]], [[pallister killian syndrome]], [[cri du chat syndrome]], [[senger syndrome]], [[galloway mowat syndrome]], [[CASK mutation]], [[cerebellar agenesis]].
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|'''Metabolic diseases'''
|'''Metabolic diseases'''
|adenylsuccinase deficiency, molybdenum cofactor deficiency, smith-lemli-opitz syndrome, Zellweger syndrome, copper metabolism disease, mucopolysacchridoses,mitochondrial disorders, congenital glycosylation disorders
|[[adenylsuccinase deficiency]], [[molybdenum cofactor]] deficiency, [[smith-lemli-opitz syndrome]], [[Zellweger syndrome]], [[copper metabolism disease]], [[mucopolysacchridoses]],[[mitochondrial disorders]], [[congenital glycosylation disorders]]
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|
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|-
|-
|'''Prenatal infections'''
|'''Prenatal infections'''
|Congenital cytomegalo virus
|[[Congenital cytomegalo virus]]
|
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|
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|-
|-
|'''Prenatal teratogens'''
|'''Prenatal teratogens'''
|Antiepileptic drugs (valproic acid, phenytoin), retinoic acid, cocaine, alcohol
|[[Antiepileptic drugs]] ([[valproic acid]], [[phenytoin]]), [[retinoic acid]], [[cocaine]], [[alcohol]]
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|-
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|'''Disruptive lesions'''
|'''Disruptive lesions'''
|Cerebellar agenesis, cerebellar injury secondary to prematurity
|[[Cerebellar agenesis]], [[cerebellar injury]] secondary to [[prematurity]]
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|-
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|'''Brain malformations'''
|'''Brain malformations'''
|Dandy walker syndrome, Rhombencephalosynapsis, Joubert syndrome''',''' pontine tegmental cap dysplasia''',''' lissencephaly, polymicrogyria, primary microcephaly.
|[[Dandy walker syndrome]], [[Rhombencephalosynapsis]], [[Joubert syndrome]]''',''' [[pontine tegmental cap dysplasia]]''',''' [[lissencephaly]], [[polymicrogyria]], [[primary microcephaly]].
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To review risk factors for the development of [disease name], click [[Pericarditis causes#Overview|here]].
To review risk factors for the development of [disease name], click [[Pericarditis causes#Overview|here]].


== Differentiating [disease name] from other Diseases ==
== Differentiating cerebellar hypoplasia from other Diseases ==


* [Cerebellar hyoplasia] must be differentiated from cerebellar atrophy. Neuroimaging can help differentiate between the 2 entities. In case of cerebellar atrophy, there is loss of cerebellar parenchyma with subsequent expansion of interfolial spaces.
* [[Cerebellar hypoplasia]] must be differentiated from [[cerebellar atrophy]]. Neuroimaging can help differentiate between the 2 entities. In case of [[cerebellar atrophy]], there is loss of [[cerebellar parenchyma]] with subsequent expansion of [[interfolial spaces]] or fissures. While in [[cerebellar hypoplasia]] fissures have normal size relative to [[folia]]. <ref name="pmid15098235">{{cite journal | vauthors = Boltshauser E | title = Cerebellum-small brain but large confusion: a review of selected cerebellar malformations and disruptions | journal = American Journal of Medical Genetics. Part a | volume = 126A | issue = 4 | pages = 376–85 | date = May 2004 | pmid = 15098235 | doi = 10.1002/ajmg.a.20662 | url = | issn = | accessdate = 2020-08-15}}</ref> <ref name="pmid17869142">{{cite journal | vauthors = Poretti A, Wolf NI, Boltshauser E | title = Differential diagnosis of cerebellar atrophy in childhood | journal = European Journal of Paediatric Neurology : EJPN : Official Journal of the European Paediatric Neurology Society | volume = 12 | issue = 3 | pages = 155–67 | date = May 2008 | pmid = 17869142 | doi = 10.1016/j.ejpn.2007.07.010 | url = | issn = | accessdate = 2020-08-15}}</ref>


== Epidemiology and Demographics ==
== Epidemiology and Demographics ==


* From [1997-2011], the prevalence of [cerebellar hypoplasia] was estimated to be [1.30] cases per 100,000 births, in a study recruiting individuals from 10 states of Unites States. Prevalence of cerebellar hypoplasia increased overtime. From year 1997-2004, prevalence of cerebellar hypoplaisa was estimated to be around 0.68 per 100,000 births while it raised to 2.00 per 100,000 births from year 2005-2011. In another study, a child neurologist reported that 0.4 %(11 out of 2500) of children visiting him had cerebellar hypoplasia. Another study recruiting 188 children with developmental delays reported that 4.5% of the study population had cerebellar hypoplasia.  
* From [1997-2011], the [[prevalence]] of [[cerebellar hypoplasia]] was estimated to be [1.30] cases per 100,000 births, in a study recruiting individuals from 10 states of Unites States. [[Prevalence]] of [[cerebellar hypoplasia]] increased overtime. From year 1997-2004, [[prevalence]] of [[cerebellar hypoplasia]] was estimated to be around 0.68 per 100,000 births while it raised to 2.00 per 100,000 births from year 2005-2011.<ref name="pmid30230717">{{cite journal | vauthors = Howley MM, Keppler-Noreuil KM, Cunniff CM, Browne ML | title = Descriptive epidemiology of cerebellar hypoplasia in the National Birth Defects Prevention Study | journal = Birth Defects Research | volume = 110 | issue = 19 | pages = 1419–1432 | date = November 2018 | pmid = 30230717 | pmc = 6265081 | doi = 10.1002/bdr2.1388 | url = | issn = | accessdate = 2020-08-15}}</ref> In another study, a child neurologist reported that 0.4 %(11 out of 2500) of children visiting him had [[cerebellar hypoplasia]].<ref name="pmid8916160">{{cite journal | vauthors = Shevell MI, Majnemer A | title = Clinical features of developmental disability associated with cerebellar hypoplasia | journal = Pediatric Neurology | volume = 15 | issue = 3 | pages = 224–9 | date = October 1996 | pmid = 8916160 | doi = 10.1016/s0887-8994(96)00220-2 | url = | issn = | accessdate = 2020-08-15}}</ref> Another study recruiting 188 children with developmental delays reported that 4.5% of the study population had [[cerebellar hypoplasia]]. <ref name="pmid12878295">{{cite journal | vauthors = Wassmer E, Davies P, Whitehouse WP, Green SH | title = Clinical spectrum associated with cerebellar hypoplasia | journal = Pediatric Neurology | volume = 28 | issue = 5 | pages = 347–51 | date = May 2003 | pmid = 12878295 | doi = 10.1016/s0887-8994(03)00016-x | url = | issn = | accessdate = 2020-08-15}}</ref>


=== Age ===
=== Age ===


* [Cerebellar hypoplasia] may be detected in utero but as trans cerebellar diameter is not measured routinely in 3rd trimester so diagnosis is sometimes delayed to post-natal period. However, in case of pontocerebellar hypoplasia inutero diagnosis is considered difficult and it is mostly diagnosed after birth.
* [[Cerebellar hypoplasia]] may be detected in utero but as [[trans cerebellar diameter]] is not measured routinely in [[3rd trimester]] so diagnosis is sometimes delayed to post-natal period. <ref name="pmid16619384">{{cite journal | vauthors = Guibaud L, des Portes V | title = Plea for an anatomical approach to abnormalities of the posterior fossa in prenatal diagnosis | journal = Ultrasound in Obstetrics & Gynecology : the Official Journal of the International Society of Ultrasound in Obstetrics and Gynecology | volume = 27 | issue = 5 | pages = 477–81 | date = May 2006 | pmid = 16619384 | doi = 10.1002/uog.2777 | url = | issn = | accessdate = 2020-08-15}}</ref>However, in case of pontocerebellar hypoplasia inutero diagnosis is considered difficult and it is mostly diagnosed after birth.<ref name="pmid20803644">{{cite journal | vauthors = Graham JM, Spencer AH, Grinberg I, Niesen CE, Platt LD, Maya M, Namavar Y, Baas F, Dobyns WB | title = Molecular and neuroimaging findings in pontocerebellar hypoplasia type 2 (PCH2): is prenatal diagnosis possible? | journal = American Journal of Medical Genetics. Part a | volume = 152A | issue = 9 | pages = 2268–76 | date = September 2010 | pmid = 20803644 | pmc = 2931360 | doi = 10.1002/ajmg.a.33579 | url = | issn = | accessdate = 2020-08-15}}</ref>
 
=== Gender ===
 
* [Disease name] affects men and women equally.
 
* [Gender 1] are more commonly affected with [disease name] than [gender 2].
* The [gender 1] to [Gender 2] ratio is approximately [number > 1] to 1.


=== Race ===
=== Race ===


* There is no proven racial predilection for [cerebellar hypoplasia]. In a study, non-hispanic black maternal race was at a slightly increased risk of cerebellar hypoplasia but the results were statistically non-significant.  
* There is no proven racial predilection for [[cerebellar hypoplasia]]. In a study, non-hispanic black maternal race was at a slightly increased risk of [[cerebellar hypoplasia]] but the results were statistically non-significant.<ref name="pmid30230717">{{cite journal | vauthors = Howley MM, Keppler-Noreuil KM, Cunniff CM, Browne ML | title = Descriptive epidemiology of cerebellar hypoplasia in the National Birth Defects Prevention Study | journal = Birth Defects Research | volume = 110 | issue = 19 | pages = 1419–1432 | date = November 2018 | pmid = 30230717 | pmc = 6265081 | doi = 10.1002/bdr2.1388 | url = | issn = | accessdate = 2020-08-15}}</ref>


== Risk Factors ==
== Risk Factors ==


* Common risk factors in the development of [cerebellar hypoplasia] are [low birth weight], [preterm birth], [multiple pregnancies], [prenatal infections], [prenatal use of anti epileptic drugs], [maternal use of alcohol or cocaine]. Maternal hypertension and maternal use of vasoactive medications have also been associated with increased risk of cerebellar hypoplasia but results were not statistically significant. Postnatal glucocorticoid use in preterm infants has also been associated with poor cerebellar development and maturation.
* Common risk factors in the development of [[cerebellar hypoplasia]] are [[low birth weight]], [[preterm birth]], [[multiple pregnancies]], [[prenatal infections]], prenatal use of [[anti epileptic drugs]], maternal use of [[alcohol]] or [[cocaine]]. [[Maternal hypertension]] and maternal use of [[vasoactive medications]] have also been associated with increased risk of [[cerebellar hypoplasia]] but results were not statistically significant. [[Postnatal]] [[glucocorticoid]] use in [[preterm infants]] has also been associated with poor [[cerebellar development]] and maturation.<ref name="pmid27843009">{{cite journal | vauthors = Brossard-Racine M, Poretti A, Murnick J, Bouyssi-Kobar M, McCarter R, du Plessis AJ, Limperopoulos C | title = Cerebellar Microstructural Organization is Altered by Complications of Premature Birth: A Case-Control Study | journal = The Journal of Pediatrics | volume = 182 | issue = | pages = 28–33.e1 | date = March 2017 | pmid = 27843009 | doi = 10.1016/j.jpeds.2016.10.034 | url = | issn = | accessdate = 2020-08-15}}</ref> <ref name="pmid30230717">{{cite journal | vauthors = Howley MM, Keppler-Noreuil KM, Cunniff CM, Browne ML | title = Descriptive epidemiology of cerebellar hypoplasia in the National Birth Defects Prevention Study | journal = Birth Defects Research | volume = 110 | issue = 19 | pages = 1419–1432 | date = November 2018 | pmid = 30230717 | pmc = 6265081 | doi = 10.1002/bdr2.1388 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid24839100">{{cite journal | vauthors = Poretti A, Boltshauser E, Doherty D | title = Cerebellar hypoplasia: differential diagnosis and diagnostic approach | journal = American Journal of Medical Genetics. Part C, Seminars in Medical Genetics | volume = 166C | issue = 2 | pages = 211–26 | date = June 2014 | pmid = 24839100 | doi = 10.1002/ajmg.c.31398 | url = | issn = | accessdate = 2020-08-15}}</ref>


== Natural History, Complications and Prognosis ==
== Natural History, Complications and Prognosis ==


* Common complications of [disease name] include [complication 1], [complication 2], and [complication 3].
 
* Prognosis of cerebellar hypoplasia generally depends upon the underlying etiology. Cerebellar hypoplasia associated with non-progressive disorders (e.g abnormal brain formation during fetal development), has a relatively better prognosis. On the other hand, cerebellar hypoplasia associated with progressive conditions has poor prognosis.<ref name="urlCerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS)">{{cite web |url=https://web.archive.org/web/20150104180252/http://www.ninds.nih.gov/disorders/cerebellar_hypoplasia/cerebellar_hypoplasia.htm |title=Cerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS) |format= |work= |accessdate=2020-08-14}}</ref>
* Prognosis of [[cerebellar hypoplasia]] generally depends upon the underlying etiology. [[Cerebellar hypoplasia]] associated with non-progressive disorders (e.g abnormal brain formation during fetal development), has a relatively better prognosis. On the other hand, cerebellar hypoplasia associated with progressive conditions has poor prognosis.<ref name="urlCerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS)">{{cite web |url=https://web.archive.org/web/20150104180252/http://www.ninds.nih.gov/disorders/cerebellar_hypoplasia/cerebellar_hypoplasia.htm |title=Cerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS) |format= |work= |accessdate=2020-08-14}}</ref>


== Diagnosis ==
== Diagnosis ==
 
===Diagnostic criteria===
There is no specific diagnostic criteria for [[cerebellar hypoplasia]].
=== History and Symptoms. ===
=== History and Symptoms. ===


* Symptoms of [disease name] may include the following:<ref name="pmid19191827">{{cite journal |vauthors=Bolduc ME, Limperopoulos C |title=Neurodevelopmental outcomes in children with cerebellar malformations: a systematic review |journal=Dev Med Child Neurol |volume=51 |issue=4 |pages=256–67 |date=April 2009 |pmid=19191827 |doi=10.1111/j.1469-8749.2008.03224.x |url= |accessdate=2020-08-14}}</ref><ref name="pmid12878295">{{cite journal |vauthors=Wassmer E, Davies P, Whitehouse WP, Green SH |title=Clinical spectrum associated with cerebellar hypoplasia |journal=Pediatr. Neurol. |volume=28 |issue=5 |pages=347–51 |date=May 2003 |pmid=12878295 |doi=10.1016/s0887-8994(03)00016-x |url= |accessdate=2020-08-14}}</ref>
* Symptoms of [[cerebellar hypoplasia]] may include the following:<ref name="pmid19191827">{{cite journal |vauthors=Bolduc ME, Limperopoulos C |title=Neurodevelopmental outcomes in children with cerebellar malformations: a systematic review |journal=Dev Med Child Neurol |volume=51 |issue=4 |pages=256–67 |date=April 2009 |pmid=19191827 |doi=10.1111/j.1469-8749.2008.03224.x |url= |accessdate=2020-08-14}}</ref><ref name="pmid12878295">{{cite journal |vauthors=Wassmer E, Davies P, Whitehouse WP, Green SH |title=Clinical spectrum associated with cerebellar hypoplasia |journal=Pediatr. Neurol. |volume=28 |issue=5 |pages=347–51 |date=May 2003 |pmid=12878295 |doi=10.1016/s0887-8994(03)00016-x |url= |accessdate=2020-08-14}}</ref><ref name="pmid16970885">{{cite journal | vauthors = Ventura P, Presicci A, Perniola T, Campa MG, Margari L | title = Mental retardation and epilepsy in patients with isolated cerebellar hypoplasia | journal = Journal of Child Neurology | volume = 21 | issue = 9 | pages = 776–81 | date = September 2006 | pmid = 16970885 | doi = 10.1177/08830738060210091301 | url = | issn = | accessdate = 2020-08-14}}</ref>


:* [Seizures]
:* [[Seizures]]
:* [Behavioral abnormalities]
:* [[Behavioral abnormalities]]
:* [Muscular hypotonia]
:* [[Muscular hypotonia]]
:* [Tremors]
:* [[Tremors]]
:* [Microcephaly]
:* [[Microcephaly]]
:* [Poor/absent language/speech development]
:* [[Poor/absent language/speech development]]
:*[Intellectual disability]
:*[[Intellectual disability]]
:*[Headache]
:*[[Headache]]
:*[Hearing impairment]
:*[[Hearing impairment]]
:*[Dizzy spells]
:*[[Dizzy spells]]


=== Physical Examination ===
=== Physical Examination ===


* Physical examination may be remarkable for:<ref name="pmid12878295">{{cite journal |vauthors=Wassmer E, Davies P, Whitehouse WP, Green SH |title=Clinical spectrum associated with cerebellar hypoplasia |journal=Pediatr. Neurol. |volume=28 |issue=5 |pages=347–51 |date=May 2003 |pmid=12878295 |doi=10.1016/s0887-8994(03)00016-x |url= |accessdate=2020-08-14}}</ref>
* Physical examination may be remarkable for:<ref name="pmid12878295">{{cite journal |vauthors=Wassmer E, Davies P, Whitehouse WP, Green SH |title=Clinical spectrum associated with cerebellar hypoplasia |journal=Pediatr. Neurol. |volume=28 |issue=5 |pages=347–51 |date=May 2003 |pmid=12878295 |doi=10.1016/s0887-8994(03)00016-x |url= |accessdate=2020-08-14}}</ref><ref name="pmid19191827">{{cite journal |vauthors=Bolduc ME, Limperopoulos C |title=Neurodevelopmental outcomes in children with cerebellar malformations: a systematic review |journal=Dev Med Child Neurol |volume=51 |issue=4 |pages=256–67 |date=April 2009 |pmid=19191827 |doi=10.1111/j.1469-8749.2008.03224.x |url= |accessdate=2020-08-14}}</ref>


:* [Truncal ataxia]
:* [[Truncal ataxia]]
:* [Hypotonia]
:* [[Hypotonia]]
:* [Abnormal ocular movements]
:* [[Abnormal ocular movements]]
:* [Intention tremors]
:* [[Intention tremors]]
:* [Speech/language abnormalities]
:* [[Speech/language abnormalities]]
:* [Developmental delay in children]
:* [[Developmental delay in children]]


<br />
<br />
===Laboratory findings===
*There are no specific laboratory findings associated with [[cerebellar hypoplasia]]. Lab findings may be abnormal depending upon the underlying etiology.
===Electrocardiogram===
There are no [[ECG]] findings associated with [[cerebellar hypoplasia]].
===X-ray===
There are no [[x-ray]] findings associated with [[cerebellar hypoplasia]].
===Echocardiography===
There are no echocardiographic findings associated with [[cerebellar hypoplasia]].


=== CT scan ===
=== CT scan ===
[Brain] CT scan may be helpful in the diagnosis of [cerebellar hypoplasia] but MRi remains the diagnostic study of choice.
[[Brain]] CT scan may be helpful in the diagnosis of [cerebellar hypoplasia] but MRI remains the diagnostic study of choice.


=== MRI ===
=== MRI ===
MRI is the diagnostic study of choice for diagnosis of cerebellar hypoplasia. Findings on MRI suggestive of cerebellar hypoplasia include small trans cerebellar diameter, reduced cerebellar volume with intact cerebellar morphology and prominent subarachnoid spaces. It can also identify one of the 4 patterns of cerebellar hypoplasia that include unilateral cerebellar hypoplasia, hypoplasia involving cerebellar vermis, hypoplasia involving both cerebellar hemispheres and vermis, pontocerebellar hypoplasia. Sometimes in pontocerebellar hypoplasia, cerebellar hemispheres are so profoundly involved that neuroimaging reveals a "dragon fly" appearance showing small flattened cerebellar hemispheres with relatively spared vermis.  
[[MRI]] is the diagnostic study of choice for diagnosis of [[cerebellar hypoplasia]]. Findings on [[MRI]] suggestive of [[cerebellar hypoplasia]] include small [[trans cerebellar diameter]], reduced [[cerebellar volume]] with intact [[cerebellar morphology]], and prominent [[subarachnoid spaces]]. It can also identify one of the 4 patterns of [[cerebellar hypoplasia]] that include [[unilateral cerebellar hypoplasia]], hypoplasia involving [[cerebellar vermis]], hypoplasia involving both [[cerebellar hemispheres]] and [[vermis]], [[pontocerebellar hypoplasia]].<ref name="pmid20432023">{{cite journal | vauthors = Garel C | title = Posterior fossa malformations: main features and limits in prenatal diagnosis | journal = Pediatric Radiology | volume = 40 | issue = 6 | pages = 1038–45 | date = June 2010 | pmid = 20432023 | doi = 10.1007/s00247-010-1617-7 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid24839100">{{cite journal | vauthors = Poretti A, Boltshauser E, Doherty D | title = Cerebellar hypoplasia: differential diagnosis and diagnostic approach | journal = American Journal of Medical Genetics. Part C, Seminars in Medical Genetics | volume = 166C | issue = 2 | pages = 211–26 | date = June 2014 | pmid = 24839100 | doi = 10.1002/ajmg.c.31398 | url = | issn = | accessdate = 2020-08-15}}</ref> Sometimes in [[pontocerebellar hypoplasia]], [[cerebellar hemispheres]] are so profoundly involved that neuroimaging reveals a [["dragonfly"]] appearance showing small flattened [[cerebellar hemispheres]] with relatively spared vermis. <ref name="pmid29891067">{{cite journal | vauthors = Lerman-Sagie T, Prayer D, Stöcklein S, Malinger G | title = Fetal cerebellar disorders | journal = Handbook of Clinical Neurology | volume = 155 | issue = | pages = 3–23 | date = 2018 | pmid = 29891067 | doi = 10.1016/B978-0-444-64189-2.00001-9 | url = | issn = | accessdate = 2020-08-15}}</ref>




Line 147: Line 147:
=== Other Imaging Studies ===
=== Other Imaging Studies ===


Inutero ultrasonography can reveal reduced trans cerebellar diameter alongwith other findings suggestive of cerebellar hypoplasia.
[[Inutero]] [[ultrasonography]] can reveal reduced [[trans cerebellar diameter]] along with other findings suggestive of [[cerebellar hypoplasia]].
[Diffusion tensor imaging] may be helpful in the diagnosis of [cerebellar hypoplasia]. Cerebellar microarchitecture and cerebellar white matter tracts along with their connections are ellaborated by diffuse tensor imaging. Disruptive lesions can be better identified using susceptibilty weighted imaging as it has high sensitivity for blood products and calcifications.
[[Diffusion tensor imaging]] may be helpful in the diagnosis of [[cerebellar hypoplasia]]. Cerebellar microarchitecture and cerebellar [[white matter tracts]] along with their connections are ellaborated by [[diffuse tensor imaging]]. [[Disruptive lesions]] can be better identified using susceptibilty weighted imaging as it has high [[sensitivity]] for blood products and [[calcifications]].<ref name="pmid23288476">{{cite journal | vauthors = Poretti A, Meoded A, Rossi A, Raybaud C, Huisman TA | title = Diffusion tensor imaging and fiber tractography in brain malformations | journal = Pediatric Radiology | volume = 43 | issue = 1 | pages = 28–54 | date = January 2013 | pmid = 23288476 | doi = 10.1007/s00247-012-2428-9 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid24925729">{{cite journal | vauthors = Bosemani T, Poretti A, Huisman TA | title = Susceptibility-weighted imaging in pediatric neuroimaging | journal = Journal of Magnetic Resonance Imaging : JMRI | volume = 40 | issue = 3 | pages = 530–44 | date = September 2014 | pmid = 24925729 | doi = 10.1002/jmri.24410 | url = | issn = | accessdate = 2020-08-15}}</ref><ref name="pmid20432023">{{cite journal | vauthors = Garel C | title = Posterior fossa malformations: main features and limits in prenatal diagnosis | journal = Pediatric Radiology | volume = 40 | issue = 6 | pages = 1038–45 | date = June 2010 | pmid = 20432023 | doi = 10.1007/s00247-010-1617-7 | url = | issn = | accessdate = 2020-08-15}}</ref>


===Other Diagnostic Studies===
There are no other diagnostic studies associated with [[cerebellar hypoplasia]].
<br />
<br />


== Treatment ==
== Treatment ==


* There is no standard treatment for [cerebellar hypoplasia]; the mainstay of therapy is symptomatic and supportive care and largely depends upon the underlying etiology.
* There is no standard treatment for [[cerebellar hypoplasia]]; the mainstay of therapy is symptomatic and supportive care and largely depends upon the underlying etiology.<ref name="urlCerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS)">{{cite web | url = +https://web.archive.org/web/20150104180252/http://www.ninds.nih.gov/disorders/cerebellar_hypoplasia/cerebellar_hypoplasia.htm | title = Cerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS) | author = | authorlink = | coauthors = | date = | format = | work = | publisher = | pages = | language = | archiveurl = | archivedate = | quote = | accessdate = 2020-08-15}}</ref>


=== Prevention ===
=== Prevention ===


* There are no primary preventive measures available for [disease name].
* There are no primary preventive measures available for [cerebellar hypoplasia].


* Effective measures for the primary prevention of [disease name] include [measure1], [measure2], and [measure3].


* Once diagnosed and successfully treated, patients with [disease name] are followed-up every [duration]. Follow-up testing includes [test 1], [test 2], and [test 3].


== References ==
== References ==

Latest revision as of 06:33, 19 October 2020

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmad Muneeb, MBBS[2]

Synonyms and keywords:

Overview

Cerebellar hypoplasia is a condition in which cerebellar volume is significantly reduced but its shape remains intact. It occurs in multiple diseases and has various patterns on neuroimaging. Variety of prenatal insults have been associated with cerebellar hypoplasia. Diagnosis of cerebellar hypoplasia can be made prenatally as well as postnatally. Prognosis and treatment of cerebellar hypoplasia largely depend upon the underlying etiology.

Historical prespective

There is no available data on historical perspective of cerebellar hypoplasia.

Classification

Pathophysiology

Causes

Cerebellar hypoplasia may be caused by variety of etiologies listed below in the table.[1]


Disease processes/groups Examples
Genetic disorders gillepsie syndrome, beckwith-Wiedemann syndrome, ritscher shinzel syndrome, hoyeraal hreidarsson syndrome, charge syndrome,

endostel sclerosis, Delleman syndrome, epilepsy and permanent neonatal diabetes syndrome, neurofibromatosis, pseudo torch syndrome,

velocardiofacial syndrome, cohen syndrome, pallister killian syndrome, cri du chat syndrome, senger syndrome, galloway mowat syndrome, CASK mutation, cerebellar agenesis.

Metabolic diseases adenylsuccinase deficiency, molybdenum cofactor deficiency, smith-lemli-opitz syndrome, Zellweger syndrome, copper metabolism disease, mucopolysacchridoses,mitochondrial disorders, congenital glycosylation disorders
Prenatal infections Congenital cytomegalo virus
Prenatal teratogens Antiepileptic drugs (valproic acid, phenytoin), retinoic acid, cocaine, alcohol
Disruptive lesions Cerebellar agenesis, cerebellar injury secondary to prematurity
Brain malformations Dandy walker syndrome, Rhombencephalosynapsis, Joubert syndrome, pontine tegmental cap dysplasia, lissencephaly, polymicrogyria, primary microcephaly.

To review risk factors for the development of [disease name], click here.

Differentiating cerebellar hypoplasia from other Diseases

Epidemiology and Demographics

Age

Race

Risk Factors

Natural History, Complications and Prognosis

  • Prognosis of cerebellar hypoplasia generally depends upon the underlying etiology. Cerebellar hypoplasia associated with non-progressive disorders (e.g abnormal brain formation during fetal development), has a relatively better prognosis. On the other hand, cerebellar hypoplasia associated with progressive conditions has poor prognosis.[16]

Diagnosis

Diagnostic criteria

There is no specific diagnostic criteria for cerebellar hypoplasia.

History and Symptoms.

Physical Examination

  • Physical examination may be remarkable for:[12][17]


Laboratory findings

  • There are no specific laboratory findings associated with cerebellar hypoplasia. Lab findings may be abnormal depending upon the underlying etiology.

Electrocardiogram

There are no ECG findings associated with cerebellar hypoplasia.

X-ray

There are no x-ray findings associated with cerebellar hypoplasia.

Echocardiography

There are no echocardiographic findings associated with cerebellar hypoplasia.

CT scan

Brain CT scan may be helpful in the diagnosis of [cerebellar hypoplasia] but MRI remains the diagnostic study of choice.

MRI

MRI is the diagnostic study of choice for diagnosis of cerebellar hypoplasia. Findings on MRI suggestive of cerebellar hypoplasia include small trans cerebellar diameter, reduced cerebellar volume with intact cerebellar morphology, and prominent subarachnoid spaces. It can also identify one of the 4 patterns of cerebellar hypoplasia that include unilateral cerebellar hypoplasia, hypoplasia involving cerebellar vermis, hypoplasia involving both cerebellar hemispheres and vermis, pontocerebellar hypoplasia.[19][1] Sometimes in pontocerebellar hypoplasia, cerebellar hemispheres are so profoundly involved that neuroimaging reveals a "dragonfly" appearance showing small flattened cerebellar hemispheres with relatively spared vermis. [20]



Other Imaging Studies

Inutero ultrasonography can reveal reduced trans cerebellar diameter along with other findings suggestive of cerebellar hypoplasia. Diffusion tensor imaging may be helpful in the diagnosis of cerebellar hypoplasia. Cerebellar microarchitecture and cerebellar white matter tracts along with their connections are ellaborated by diffuse tensor imaging. Disruptive lesions can be better identified using susceptibilty weighted imaging as it has high sensitivity for blood products and calcifications.[21][22][19]

Other Diagnostic Studies

There are no other diagnostic studies associated with cerebellar hypoplasia.

Treatment

  • There is no standard treatment for cerebellar hypoplasia; the mainstay of therapy is symptomatic and supportive care and largely depends upon the underlying etiology.[16]

Prevention

  • There are no primary preventive measures available for [cerebellar hypoplasia].


References


External links

Template:Disease-stub

  1. 1.0 1.1 1.2 1.3 Poretti A, Boltshauser E, Doherty D (June 2014). "Cerebellar hypoplasia: differential diagnosis and diagnostic approach". Am J Med Genet C Semin Med Genet. 166C (2): 211–26. doi:10.1002/ajmg.c.31398. PMID 24839100. |access-date= requires |url= (help)
  2. "Cerebellar hypoplasia | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program". Retrieved 2020-08-15.
  3. Subashini C, Dhanesh SB, Chen CM, Riya PA, Meera V, Divya TS, Kuruvilla R, Buttler K, James J (February 2017). "Wnt5a is a crucial regulator of neurogenesis during cerebellum development". Scientific Reports. 7: 42523. doi:10.1038/srep42523. PMC 5311982. PMID 28205531. |access-date= requires |url= (help)
  4. Davis CA, Joyner AL (December 1988). "Expression patterns of the homeo box-containing genes En-1 and En-2 and the proto-oncogene int-1 diverge during mouse development". Genes & Development. 2 (12B): 1736–44. doi:10.1101/gad.2.12b.1736. PMID 2907320. |access-date= requires |url= (help)
  5. Jiang C, Gai N, Zou Y, Zheng Y, Ma R, Wei X, Liang D, Wu L (January 2017). "WDR73 missense mutation causes infantile onset intellectual disability and cerebellar hypoplasia in a consanguineous family". Clinica Chimica Acta; International Journal of Clinical Chemistry. 464: 24–29. doi:10.1016/j.cca.2016.10.029. PMID 27983999. |access-date= requires |url= (help)
  6. Poretti A, Prayer D, Boltshauser E (September 2009). "Morphological spectrum of prenatal cerebellar disruptions". European Journal of Paediatric Neurology : EJPN : Official Journal of the European Paediatric Neurology Society. 13 (5): 397–407. doi:10.1016/j.ejpn.2008.09.001. PMID 18945628. |access-date= requires |url= (help)
  7. Barth PG (1993). "Pontocerebellar hypoplasias. An overview of a group of inherited neurodegenerative disorders with fetal onset". Brain & Development. 15 (6): 411–22. doi:10.1016/0387-7604(93)90080-r. PMID 8147499. |access-date= requires |url= (help)
  8. Boltshauser E (May 2004). "Cerebellum-small brain but large confusion: a review of selected cerebellar malformations and disruptions". American Journal of Medical Genetics. Part a. 126A (4): 376–85. doi:10.1002/ajmg.a.20662. PMID 15098235. |access-date= requires |url= (help)
  9. Poretti A, Wolf NI, Boltshauser E (May 2008). "Differential diagnosis of cerebellar atrophy in childhood". European Journal of Paediatric Neurology : EJPN : Official Journal of the European Paediatric Neurology Society. 12 (3): 155–67. doi:10.1016/j.ejpn.2007.07.010. PMID 17869142. |access-date= requires |url= (help)
  10. 10.0 10.1 10.2 Howley MM, Keppler-Noreuil KM, Cunniff CM, Browne ML (November 2018). "Descriptive epidemiology of cerebellar hypoplasia in the National Birth Defects Prevention Study". Birth Defects Research. 110 (19): 1419–1432. doi:10.1002/bdr2.1388. PMC 6265081. PMID 30230717. |access-date= requires |url= (help)
  11. Shevell MI, Majnemer A (October 1996). "Clinical features of developmental disability associated with cerebellar hypoplasia". Pediatric Neurology. 15 (3): 224–9. doi:10.1016/s0887-8994(96)00220-2. PMID 8916160. |access-date= requires |url= (help)
  12. 12.0 12.1 12.2 Wassmer E, Davies P, Whitehouse WP, Green SH (May 2003). "Clinical spectrum associated with cerebellar hypoplasia". Pediatric Neurology. 28 (5): 347–51. doi:10.1016/s0887-8994(03)00016-x. PMID 12878295. |access-date= requires |url= (help)
  13. Guibaud L, des Portes V (May 2006). "Plea for an anatomical approach to abnormalities of the posterior fossa in prenatal diagnosis". Ultrasound in Obstetrics & Gynecology : the Official Journal of the International Society of Ultrasound in Obstetrics and Gynecology. 27 (5): 477–81. doi:10.1002/uog.2777. PMID 16619384. |access-date= requires |url= (help)
  14. Graham JM, Spencer AH, Grinberg I, Niesen CE, Platt LD, Maya M, Namavar Y, Baas F, Dobyns WB (September 2010). "Molecular and neuroimaging findings in pontocerebellar hypoplasia type 2 (PCH2): is prenatal diagnosis possible?". American Journal of Medical Genetics. Part a. 152A (9): 2268–76. doi:10.1002/ajmg.a.33579. PMC 2931360. PMID 20803644. |access-date= requires |url= (help)
  15. Brossard-Racine M, Poretti A, Murnick J, Bouyssi-Kobar M, McCarter R, du Plessis AJ, Limperopoulos C (March 2017). "Cerebellar Microstructural Organization is Altered by Complications of Premature Birth: A Case-Control Study". The Journal of Pediatrics. 182: 28–33.e1. doi:10.1016/j.jpeds.2016.10.034. PMID 27843009. |access-date= requires |url= (help)
  16. 16.0 16.1 "Cerebellar Hypoplasia Information Page: National Institute of Neurological Disorders and Stroke (NINDS)". Retrieved 2020-08-14.
  17. 17.0 17.1 Bolduc ME, Limperopoulos C (April 2009). "Neurodevelopmental outcomes in children with cerebellar malformations: a systematic review". Dev Med Child Neurol. 51 (4): 256–67. doi:10.1111/j.1469-8749.2008.03224.x. PMID 19191827. |access-date= requires |url= (help)
  18. Ventura P, Presicci A, Perniola T, Campa MG, Margari L (September 2006). "Mental retardation and epilepsy in patients with isolated cerebellar hypoplasia". Journal of Child Neurology. 21 (9): 776–81. doi:10.1177/08830738060210091301. PMID 16970885. |access-date= requires |url= (help)
  19. 19.0 19.1 Garel C (June 2010). "Posterior fossa malformations: main features and limits in prenatal diagnosis". Pediatric Radiology. 40 (6): 1038–45. doi:10.1007/s00247-010-1617-7. PMID 20432023. |access-date= requires |url= (help)
  20. Lerman-Sagie T, Prayer D, Stöcklein S, Malinger G (2018). "Fetal cerebellar disorders". Handbook of Clinical Neurology. 155: 3–23. doi:10.1016/B978-0-444-64189-2.00001-9. PMID 29891067. |access-date= requires |url= (help)
  21. Poretti A, Meoded A, Rossi A, Raybaud C, Huisman TA (January 2013). "Diffusion tensor imaging and fiber tractography in brain malformations". Pediatric Radiology. 43 (1): 28–54. doi:10.1007/s00247-012-2428-9. PMID 23288476. |access-date= requires |url= (help)
  22. Bosemani T, Poretti A, Huisman TA (September 2014). "Susceptibility-weighted imaging in pediatric neuroimaging". Journal of Magnetic Resonance Imaging : JMRI. 40 (3): 530–44. doi:10.1002/jmri.24410. PMID 24925729. |access-date= requires |url= (help)