Abstract
1247
Objectives To study the brain perfusion abnormalities in patients with acute anticholinesterase poisoning (ACh Po)and correlate it with neurocognitive dysfunction at initial admission and at three months
Methods Twenty eight (14M: 14F; mean age 26.4 ± 10.1 yrs) subjects with history of acute ACh Po, clinical symptoms consistent with the ACh Po and low serum butyrylcholinesterase levels were included in the study. All the study subjects underwent 99mTc-ECD brain SPECT and the reconstructed images were interpreted visually for any perfusion abnormality. Neurocognitive tests were performed by a clinical psychologist on admission and at 3-months
Results Perfusion abnormalities were present in 96% of the patients. 39% has abnormalities in a single region, while 21% had abnormalities in more than 4 regions. Right occipital cortex was involved in 64% and left occipital was involved in 43%. Left frontal and parietal were the least involved (11% and 18% respectively). Neuro-cognitive psychological analysis indicated significant impairment in the faculties related to attention, sequencing, memory, mental flexibility, visual search and motor functioning at initial admission with improvement at three months follow up. However, there was no significant correlation between the number of perfusion defects and neurocognitive testing. This could be as a result of the perfusion defects being secondary to factors besides poisoning such as atropine administration. Associated events like convulsions, anoxia, respiratory failure and cardiac arrhythmias that these patients suffered during the acute cholinergic syndrome may also contribute to the observed perfusion defects.
Conclusions Most patients have brain perfusion abnormalities after acute ACh Po. Occipital cortex is frequently involved. No correlation was observed between the number of perfusion abnormalities and neuro-cognitive deficits