The human diencephalon is composed of several regions. The thalamus which relays sensory information to the cerebrum, processes visual and auditory stimuli, and generates some emotions, among other functions.he human diencephalon is composed of several regions. The thalamus which relays sensory information to the cerebrum, processes visual and auditory stimuli, and generates some emotions, among other functions.
The LASIK surgery is performed by an ophthalmologist who uses a laser or microkeratome to reshape the eye's cornea in order to improve visual acuity. For most patients, LASIK provides a permanent alternative to eyeglasses or contact lenses.
Ultimately, laser eye surgery can correct astigmatism in most patients. Those with severe astigmatism may require multiple surgeries to achieve 20/20 vision or to eliminate the need for eyeglasses or contact lenses. Those who have mild or moderate astigmatism are usually the best candidates for LASIK eye surgery.