Cerebral blood flow abnormalities in cerebral palsied children with a normal CT scan

Cerebral palsy (CP) is often a consequence of a hypoxic-ischemic encephalopathy and/or intracerebral hemorrhage secondary to pre- and peri-natal asphyxia. Hypodense lesions on the CT-scan are found in about 70 to 80% of CP-patients. In the present study, regional cerebral blood flow (CBF) was measured in CP-patients having a normal CT-scan. The aim was to correlate the CBF changes with the clinical and the etiologic findings. CBF was measured by xenon-133 inhalation and single photon emission computer tomography. The mean CBF value in 20 CP-patients, age 6-19 years, was 67 +/- 11 (1 SD) ml/100g/min, the same value as found in the 9 normal children. However, 16 of the 20 CP-patients had focal hypoperfused areas on the tomographic flow map. In the preterm infants (n = 7) the hypoperfused areas were mainly located in the posterior watershed areas, often in one hemisphere only. In the term infants (n = 13) both asymmetrical and symmetrical hypoperfused areas were observed in the anterior and posterior watershed areas. In addition, several children had larger low flow areas in the frontal and fronto-parietal lobes. In both groups, a relatively poor concordance was observed between the clinical findings and the expected location of the low flow area.