Presented at the Neonatal Society 2004 Spring Meeting.
Srinivasan L1, Allsop J2, Counsell S2, Boardman J1, Rutherford M2, Edwards AD1,2
1 Department of Paediatrics, Imperial College Faculty of Medicine, Hammersmith Hospital, London, UK
2 Imaging Sciences Department, MRC Clinical Sciences Centre, Imperial College Faculty of Medicine, Hammersmith Hospital, London, UK
Introduction: Preterm infants are at increased risk of neurodevelopmental delay, cognitive dysfunction, behavioural and emotional disturbances (1-3). The role of the cerebellum in these adverse outcomes is unclear. Previous studies have shown that the size of the cerebellum in preterm infants at ages 8-15 years are reduced compared to control children (4).
Aim: The objective of this study was to determine whether absolute cerebellar volumes differ between preterm infants at term equivalent age and term born infants and to assess whether cerebellar volume is influenced by the presence of supratentorial white matter pathology.
Methods: MR images were obtained from 90 preterm infants of mean (SD) 29.6 (2.7) weeks gestational age and 13 control term infants using a 1.5 Tesla MR Eclipse system. Images were assessed for the presence of focal lesions including periventricular leucomalacia and porencephalic cysts resulting from haemorrhagic infarction. Infants with primary cerebellar abnormalities were excluded. The volume of the cerebellum was quantified by manual outlining of MRI T1 weighted volume acquisition images.
Results: In preterm infants at term equivalent age median cerebellar volume was 25.6 mL, and in term control infants it was 26.9 mL: this was not significantly different. In preterm infants with supratentorial focal lesions cerebellar volumes were significantly reduced compared to infants without lesions (means 22.3 vs 25.9 mL p = 0.009). The cerebellar volumes of preterm infants whose gestational age at birth was less than 28 weeks was significantly reduced compared to infants whose gestational age was more than 28 weeks and from the term infants (means 23.2, 26.1, 26.9 mL respectively; p = 0.01). However the effect of gestational age on cerebellar volume failed to reach significance once infants with focal lesions were excluded (p=0.07).
Conclusions: In preterm infants at term equivalent age supratentorial focal lesions are associated with smaller cerebellar volume.
References
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2. Vohr BR et al Pediatrics. 2000; 105(6):1216-1226.
3. Wood NS et al N Engl J Med. 2000; 343(6):378-384.
4. Allin M. Brain 2001; 124(Pt 1):60-66.