I have been wearing niqab for a long time. In the last few years, I started experiencing sharp pain in my eyes, so I went to an ophthalmologist and he recommended that I take my niqab off. Latter on, my sight became poor and I fell to the ground several times. It is worth pointing out that I can`t wear niqab while having eyeglasses on. Is it permissible for me to take my niqab off?