Reduce light reflection on image

[DidAus]

Hi everyone,

I'm currently programming an application that intends to detects wrinkles on a face picture. So far I've gpt quite good results, except for some parts of the images : these where flash light is reflected on the skin.

So, my question is as follow :
Is there any way to reduce this light reflection on the skin, without losing information about the wrinkles (i do not want to "delete" wrinkles, just reduce reflection) ?

A typical problematic image i'm facing is attached.

Thanks!