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13         SA JOURNAL OF RADIOLOGY • March 2010

A female neonate was delivered at 30 weeks’ gestation to a mother with 
suspected bilateral periventricular nodular heterotopia (PNH) on com-
puted tomography brain scan. Antenatal ultrasound (US) performed at 
28 weeks’ gestation showed mild lateral cerebral ventricle dilatation, but 
no other fetal anomalies. Clinical examination revealed mild dysmor-
phic features: facial and skull asymmetry, square-shaped ears, and long 
tapering fingers. Chromosomal analysis showed a 46XX karyotype.

Cerebral US revealed asymmetry and irregular dilatation of the 
lateral ventricles (Figs 1 and 2). These findings are nonspecific and can 
be associated with post-infectious, post-ischaemic and/or post-haemor-
rhagic periventricular infarction.1 However, a scan through the extreme 
lateral margin of the lateral ventricle revealed multiple large nodules 
covering the lateral aspects of the frontal horn and body of the lateral 

ventricles (Fig. 3). The nodules were better demonstrated by rotating the 
US probe to focus predominantly on the lateral and inferior aspects of 
the frontal horn (Fig. 4).

PNH is a neuronal migration disorder characterised by nodules 
of ectopic neurons adjacent to the lateral ventricles, owing to failed 
migration of neurons from the germinal zone towards the cortical 
plate.2 Classical bilateral PNH is the most common type and, in more 

Bilateral periventricular nodular heterotopia – 
neonatal cranial ultrasound

A R Horn, MB ChB, DCH (SA), MRCP (UK), 
FCPaed (SA), Cert Neon (SA)

Neonatal Medicine, School of Child and Adolescent Health, University of 
Cape Town

A Nel, MB ChB, DCH (SA), MMED Paed
Department of Paediatrics and Child Health, School of Medicine, University 

of the Free State, Bloemfontein

M F Urban, MB BCh, MRCP (UK), FCPaed 
(SA), Cert Med Genet (SA)

Division of Human Genetics, University of Cape Town

Fig. 1. Parasagittal US scan through the body of the left lateral 
ventricle.

Fig. 2. Coronal US scan through the body of the lateral ventricles.

Fig. 3. Parasagittal US scan through the lateral aspect of the left lateral 
ventricle.

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14         SA JOURNAL OF RADIOLOGY • March 2010

than 50% of cases, is due to mutations of the X-linked Filamin A gene.2 
Most affected females develop seizures, with variable age of onset and 
type. Dyslexia is common but intellect is usually normal to borderline. 
Hypoplasia of the cerebellar vermis and valvular heart disease are com-
monly associated, but neither were present in this neonate.3

PNH is usually diagnosed on magnetic resonance imaging but the 
US scans obtained in this patient demonstrate nodules that are typical of 
bilateral PNH.1 Previously published ultrasound images of neonates with 
this condition4 have not clearly demonstrated the distribution and size of 
the nodules as shown in this neonate.

We thank Professor Linda de Vries for comments on the manuscript 
and images.

1.  De Vries LS, Groenendaal F. Neuroimaging in the preterm infant. Ment Retard Dev Disabl Res Rev 2002; 8: 
273-280.

2.  Spalice A, Parisi P, Nicita F, Pizzardi G, Del Balzo F, Iannetti P. Neuronal migration disorders: clinical, 
neuroradiologic and genetics aspects. Acta Paediatr 2009; 98: 421-433.

3.  Parrini E, Ramazzotti A, Dobyns WB, et al. Periventricular heterotopia: phenotypic heterogeneity and 
correlation with Filamin A mutations. Brain 2006; 129: 1892-1906.

4.  Pellicer A, Cabañas F, Pérez-Higueras A, García-Alix A, Quero J. Neural migration disorders studied by 
cerebral ultraosund and colour Doppler flow imaging. Arch Dis Child Fetal Neonatal Ed 1995; 73: F55-61.

Fig. 4. Parasagittal US scan through the outer aspect of the left lateral 
ventricle with probe rotated to show more detail in the frontal horn.

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