Johannes Gossner (Institut für Radiologie/ Klinkum Braunschweig), J. Larsen (Institut für Radiologie/ Klinikum Braunschweig)  

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0 Newborn  

Female  

Postpartum hypotrophic and respiratory distressed newborn (intubation required) with rapidly evolving seizures.
Sonographically decreased sulcal pattern.
Sibling with known lissencephaly type 1.  

Most severe form of neuronal migration disorders (probably in 12th-16th gestational week). Current classification dpendent on when the cortical development was affected. The type 1 lissencephaly belongs to group A. In the setting of a Miller-Diecke syndrome, a monosomy 17p13 can be found, which is mostly a "de Novo" deletion or translocation.
Without visualized chromosomal abnormality it can be found as an isolated lissencephaly or in the setting of a Norman-Roberts syndrome.
However, even without visualized chromosomal abnormalities, in up to 40% of cases.a defect of the LIS 1 gene can be found, which regulates the neural migration by forming PAF (platelet activating factor).  

<- view MRI 1

MRI 1: T2 weighted axial image with markedly decreased sulcal pattern (= pachygyria) and thin cortex. Furthermore seen is a hemorrhage into the right lateral ventricle (hypointense).

<- view MRI 2

MRI 2: T1 weighted axial image demonstrates also significant pachygyria and prominent external CSF spaces. The fluid-fluid level containing hemorrhage in the posterior horns of the right lateral ventricle is better deliniated on the T1 weighted sequence.

<- view MRI 3

MRI 3: T2 weighted axial image at the level of the basal ganglia, which appear normal.

<- view MRI 4

MRI 4: Coronal CSF suppressed T2 weighted sequence (FLAIR) also demonstrates a markedly decreased sulcal pattern.

Total constellation (Consens)  

N/A  

Overall poor prognosis with marked mental retardation and early, partially therpy refractary seizures. Usually the children die before they reach the second year of life. Associated malformations are frequent.
Lissencephaly is a rare malformation. A study from the Netherlands reports 11.7 cases in 1 million newborns. Girls are slightly more frequently affected.
The cortical surface is smooth up to the 2nd trimester. First sulci and fissures can be detected by ultrasound in the 20th gestational week. Widening of the ventricles is described to be an indirect sign of a neuronal migration disorder. If this is evident, a follow up exam and/or MRI is recommended. Image findings by MRI is indicatory.  

N/A  

Miller 1963  

Barkovich AJ, Kuzniecky RI, Jackson GD, Guerrinen R, Dobyns WB
Classification system for malformations of cortical development: update 2001
Neurology 2001; 57:2168- 2178

Ghai S, Fong KW, Toi A, Chitayat A, Pantazi S, Blaser S
Prenatal US and MR imaging findings of Lissencephaly: review of fetal cerebral sulcal development
Radiographics 2006; 26: 389- 405

Gressens P
Mechanisms and Disturbances of Neuronal Migration
Pediatric Research 2000; 48: 725-730

de Rijk-van Andel JF, Arts WFM, Hofman A, Staal A, Niermeijer MF
Epidemiology of Lissencephaly Type I.
Neuroepidemiology 1991;10:200-204
 

Head-Brain and brain nerves  

congenital