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.
Some leading surgeons have already abandoned LASIK for surface treatments, such as PRK, which do not involve cutting a corneal flap. It is important to remember that LASIK is elective surgery. There is no sound medical reason to risk vision loss from unnecessary surgery.