Tuesday, October 12, 2010
Depth Perception and Ptosis
While I was observing an Occupational Therapist, I was introduced to a very interesting patient. She was a little girl adopted from Ethiopia who seemed to have an endless list of medical conditions. When I learned that she had something called "bilateral ptosis" I instantly thought of our class. Ptosis occurs when the muscles of the eyelids are not strong enough to raise the eyelid properly. Thus, bilateral ptosis is when the muscles are weak in both eyelids. There are many causes for ptosis, but in this little girl's case...the exact reason is unknown due to a lack of medical records. According to wikipedia, Ptosis may be caused by damage/trauma to the muscle which raises the eyelid, or damage to the nerve (3rd cranial nerve (oculomotor nerve)) which controls this muscle. The Occupational Therapist claimed that the patient was believed to have damage to the frontal lobe, which could explain where the ptosis, and other medical issues, stemmed from. Ptosis also tends to change the optics of the eye, causing astigmatism. Since one symptom of the ptosis is the drooping eyelid, I noticed that the patient had to severely tilt her chin upwards in order to be able to see properly. The patient's depth perception was seriously off balance. I found that she was tripping over objects that, she claimed, were much farther than they actually were. She went to grasp onto objects that were still inches away from her hands. Congenital ptosis (ptosis diagnosed at birth) unfortunately does not usually improve with time.