Dear Yuanchao,
I believe that in the case of polymicrogyric cortex, the lGI will decrease because the total cortical surface (i.e. the above term of the lGI equation) is drastically decreased by the numerous and shallower sulci. However, I did not have any occasion to formally challenge this hypothesis using the MRI of a patient with polymicrogyria. I'll be very interested to see the results if someone has any experience with lGI in patients with polymicrogyria.
Marie
On 26 nov. 08, at 13:02, Zhangyuanchao wrote:
Dear Mr or Ms, If a subject was identified with severe polymicrogyria, which is a brain malformation marked by development of numerous microgyri, what will the lgi of the subject behave? I want to know whether the lgi of the subject would increase or decrease compared with that of the brain of a normal subject. And why? Could you tell me the reason basing on the calculation method of lgi? Thanks.
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