The authors studied 60 children (aged 4 months to 9 years) with cerebral palsy by means of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) of the brain. MRI showed normal in 15 cases (25.0%) and deep white matter pathology in 37 cases (61.7%), corpus callosum abnormality in 29 cases (48.3%). In addition, abnormal intensity of thalamus or basal ganglia and delayed myelination were found in minor cases. In all of the patients except for 1 case, SPECT showed the abnormal findings SPECT demonstrated hypoperfusion of thalamus in 58 cases (96.7%), cerebellum in 27 cases (45.0%), frontal and parietal lobe in 26 cases (43.3%), basal ganglia in 23 cases (38.3%) and temporal lobe in 22 cases (36.7%). There was no significant correlation between the severity of motor developmental impairment and the radiologic findings. The results of this study suggest that MRI of the brain provides the anatomical information such as deep white matter and corpus callosum pathologies resulted from the hypoxic-ischemic insult and SPECT of the brain is a very sensitive tool for the assessment of the functional abnormalities in cerebral palsy.

It is often difficult, on the basis of clinical examination and conventional investigations, to evaluate the functional impairment of brain in children with cerebral palsy in which early detection remains a challenge. This study was designed to know the usefulness of single photon emission tomography(SPECT) of the brain with technetium-99 m hexamethylpropyleneamineoxime (^99mTc-HMPAO) as a semiquantitative method of determination of right-left asymmetries in tracer uptake and a change in antero-posterior regional cerebral blood flow(rCBF) distribution. We investigated 33 children with cerebral palsy aged from 4 months to 48 months(mean 19.3 months). The results were as follows: right to left ratio and regional index of a transverse view were useful to quantify the decrease of tracer uptake in left hemiplegia, but not in right hemiplegia who were all mild in severity, and in tetra- and diplegia in which cerebral lesions were found bilaterally; cortico-cerebellar ratios of a sagittal view were found useful to detect a decrease of rCBF distribution in tetra- and diplegia ,which was not distinct by means of right to left ratio and regional index on transverse view.

The results suggest that semiquantitative analysis of ^99mTc-HMPAO Brain SPECT would be a valuable complementary tool for determination of topographical involvement in cerebral palsy.

Ammonia is a colorless alkaline gas with a sharp pungent odor. It is widely used in industry and there are several case reports on deleterious pulmonary damage. Ammonia is also highly neurotoxic that interferes energy metabolism in the brain even with a small amount and causes encephalopat hy in patients with severe liver disease.

We experienced two patients with toxic encephalopathy and followed- up for 18 months. We assumed that ammonia was supposed to play a major role in the dysfunction of their brains. In our cases, the possible mechanisms of brain damage are as followings: ⸁ ammonia has direct toxic effect on brain by altering the energy metabolism, ⸂ inhalation of ammonia results in severe pulmonary damage and it may aggravate brain injury, and ⸃ besides ammonia itself, relatively hypoxic environment that they were exposed can take part in the brain injury.