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Clinical picture
This patient has an acute right third nerve palsy. A, In the primary position, ptosis of the right upper lid is complete. B, With the right upper lid held up by the right patient’s finger, the right eye is exodeviated approximately 40 prism diopters and is slightly hypodeviated. C, Abduction of the right eye is full. D, The right eye cannot adduct even to the midline. E, On downgaze the right eye intorts slightly, suggesting unopposed superior oblique function.
History
This 28-year-old man sustained closed head trauma in a motor vehicle accident 13 months earlier. He is concerned because his right eye is closed. When he raises his right upper lid, he notes that his eye is deviated outward, and he sees double. He would like to have the right eye straightened and his right lid raised.
Examination
Complete ptosis of the right upper lid is present. With maximum attempt at elevation using the frontalis muscle, the right upper lid moves upward about 3 mm. Forty prism diopters of exotropia and 15 prism diopters of right hypotropia are present in the primary position. The right pupil is dilated to 6 mm and does not react to light or accommodative effort. Visual acuity is OD 20/30 and OS 20/20. This patient understands that if his eye is made straighter and his lid raised, he will continue to have double vision and that this double vision may be more bothersome because the images are closer. In spite of this, he would like to have surgery to improve alignment of his eyes.
Diagnosis
Traumatic right third nerve palsy.
Treatment/Surgery
Maximum recession of the right lateral rectus 10+ mm, right superior oblique tendon transfer without trochlea fracture or maximum recession of the right lateral rectus and 10+ mm resection of the right medial rectus with 1/2 to 3/4 muscle width upshift of both muscles.
Comment
The appropriate extraocular procedure, when successful, can align or nearly align the eye with third nerve palsy, but motility is always limited. When the lid is raised, postoperatively the involved eye during fixation in the primary position is usually slightly exotropic. Frontalis suspension of the upper lid can be performed at the same time as the extraocular muscle surgery or it can be done at a second procedure. Whenever it is done, the ptosis should be undercorrected to lessen the adverse effect of corneal exposure which is the rule after frontalis lid suspension and limited upward protective movement (Bell phenomenon) of the eye. In a patient such as this, who lacks effective suppression, diplopia can be extremely bothersome. Actually, some of the most agitated and distraught patients I have treated have been of this category. This problem is especially severe when the patient with third nerve palsy is emotionally liable from brain injury. Patients with acquired third nerve palsy should be counseled thoroughly before surgery, telling them about the problems associated with postoperative diplopia. In several successfully aligned cases, it has been necessary to fit the patient with an occluding contact lens or to give glasses with an occluder lens to eliminate the diplopia. On the other hand, if suppression is present for any reason or if vision is poor in one eye alignment can be achieved and the patient is pleased. In some cases of complete acquired third nerve palsy it may be best to refrain from surgery and simply allow the ptosis to “treat” diplopia. |
