Oculomotor Nerve Palsy

Oculomotor nerve palsy is an eye condition that is due to the damage of the third cranial nerve. As the name suggests, the Oculomotor nerve supplies most of the muscles controlling eye movements. The nerve also supplies the upper eyelid muscle and the muscles responsible for pupil constriction. The result of the constriction becomes so severe that the individual fails to have normal alignment of the eye when looking straight ahead. This results in double vision.

Double vision, drooping of one eyelid, enlarged pupil, poor reaction to light, and headache and eye pain are possible symptoms of Oculomotor nerve palsy. Although it may be difficult to pinpoint the exact cause of this palsy, some key causes are brain aneurysms, infections, weak blood vessels, tumor, tissue damage, meningitis, diabetes, trauma from head injuries, migraine headaches, and congenital condition of third nerve palsy at birth. In partial Oculomotor palsy since different eye muscle groups are affected, they produce different appearances of the eye and different symptoms.

Due to limited eye movements arising from this condition, the affected individual is unable to maintain normal alignment of eyes when looking straight ahead. Such Oculomotor palsy could be congenital or acquired. There is no direct medical or surgical treatment but fortunately nearly all patients undergo spontaneous remission of the palsy within six to eight weeks. And any treatment during the symptomatic phase is aimed at alleviating symptoms such as pain and double vision. While non steroidal anti-inflammatory drugs are the first line treatment of choice for the pain, patching one-eye is a practical short term solution. In some persons, if the degree of deviation is smaller, double vision is achieved using horizontal or vertical prisms. If the palsy is not resolved even after a year, then eye muscle surgery and eyelid surgery is done to align the eyes and correct the drooping eyelid.