Clinico-radiological Profile of Children with Pontocerebellar Hypoplasia
Ananthanarayanan Kasinathan1, Naveen Sankhyan2, Tessa Van Dijk3
1Department of Pediatrics, Mahatma Gandhi Medical College and Research Institute (MGMCRI), Pondicherry, India.
Insights
Pontocerebellar hypoplasia (PCH) is a rare brain disorder affecting infants. Diagnosis relies on severe microcephaly and specific brain imaging findings, as genetic testing for a common mutation was negative in this case series.
Area of Science:
- Neuroscience
- Pediatric Neurology
- Genetics
Background:
- Pontocerebellar hypoplasia (PCH) is a group of prenatal-onset neurodevelopmental disorders affecting the pons and cerebellum.
- It presents with significant developmental delays and characteristic brain abnormalities.
Purpose of the Study:
- To describe the clinical, radiological, and genetic profiles of four infants diagnosed with PCH.
- To highlight diagnostic criteria and clinical outcomes for PCH.
Main Methods:
- Retrospective review of children with psychomotor retardation.
- Inclusion criteria: clinical signs of developmental delay, severe microcephaly, and radiological evidence of cerebellar hypoplasia and pontine hypoplasia.
- Investigations included neuroimaging, EEG, biochemical tests, and genetic analysis for the *TSEN54* p.A307S mutation.
Main Results:
- Four out of 101 evaluated children met PCH criteria.
- All four presented with psychomotor retardation, severe microcephaly, spasticity, bipyramidal signs, and epileptic spasms.
- Radiological findings confirmed severe cerebellar hypoplasia with pontine attenuation; two showed a 'dragonfly' cerebellar appearance.
- The common *TSEN54* p.A307S mutation was not detected.
Conclusions:
- Pontocerebellar hypoplasia should be suspected in infants with progressive psychomotor retardation and severe microcephaly.
- Cerebellar hypoplasia and pontine attenuation are key diagnostic radiological features of PCH.
Aims And Objectives:
Pontocerebellar hypoplasia (PCH) constitutes a heterogeneous group of neurodegenerative/neurodevelopmental disorder of pons and cerebellum with onset in prenatal period. This study aimed to discuss the clinical, radiological profile, and outcome of four infants with PCH attending our center.
Materials And Methods:
Data of children with psychomotor retardation seen between January 2015 and December 2015 at neurodevelopmental clinic was retrieved. PCH was defined by clinical and radiological criteria. Clinical features included were delay in attainment of milestones in more than two developmental domains accompanied by severe microcephaly. Radiological evidence of cerebellar volume loss with hypoplasia of pons was included. Patient charts were reviewed for clinical features, neuroimaging, electroencephalography, and biochemical investigations including serum and cerebrospinal lactate. Molecular genetic testing for the common p.A307S mutation in TSEN54 of the cases and their parents were also analyzed.
Results:
During this period, 101 children with psychomotor retardation were evaluated at our center. Of the 101, four children were with clinical and radiological evidence of PCH. In addition to psychomotor retardation and severe microcephaly, spasticity, bipyramidal signs, and epileptic spasms were universal in all four children. Three of the four children had optic atrophy and two had sensorineural hearing loss. Severe cerebellar hypoplasia with attenuated pons was seen in all four children. Two children had dragonfly appearance of cerebellum on coronal section. The commonest TSEN54 p.A307S mutation in children and their parents was not detected.
Conclusion:
A heightened index of suspicion for PCH is merited in infants with progressive psychomotor retardation and severe microcephaly. Cerebellar hypoplasia with pontine attenuation forms the mainstay of diagnosis of PCH.
