Both pupils too dilated; one dilates with bright light

[aliaat]

Hi,

24F Dx'd w/MS 2.5 yrs ago. Went to neuro-ophthalmologist today, said both pupils are too dilated/large (7.5mm). This has also been documented in July, and again in September and Nov. Before that, no pupil abnormality. She said probably Adie's pupil (bilateral), but could not explain the left pupil dilating in bright light. I did have internuclear ophthalmoplegia in left eye from July-Sept.

What would explain this abnormal pupil reaction? I'm not on any medication, and am arranging an MRI in the next few weeks. I'm just confused about this pupils thing. I understand Adie's pupil is normally benign, but seeing that these things have only come up during the course of my MS, can't help but wonder!

Any explanation/resources would be greatly appreciated!

[CCF-Neuro-M.D.-SH]

First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes.    
   Adie's pupils are possible, but there are also other possibilities exist that are related to your multiple scelerosis.  One such possibility, is relative afferent pupillary defects (RAPD) in both eyes due to past history of optic neuritis.  Optic neuritis is common in patients with multiple sclerosis and results in demyelination of the optic nerves (nerves that go to the eye).  Demyelination results in nerve dysfunction.  One of the functions of the optic nerves is to send the signals into the brain that light is being detected and then the brain constricts the pupils through parasympathetic fibers (autonomic) of the third cranial nerve.  If the brain does not recieve adequate signals from a dysfunctional optic nerve (from optic neuritis) it does not constrict the pupils.  Other possiblities include dysfunction in the brainstem nuclei that control the output to the pupils (also caused by multiple sclerosis related demyelination), and autonomic dysfuntion which also occurs in MS.  Visual evoked potentials can evaluate for past optic neuritis and an MRI of the brain would evaluate for demyelination in the brainstem.
I hope this has been helpful.

[aliaat]

Sorry, other update. L pupil dilates to light in both bright and dim environment. MRI with contrast showed on area of increased Gd uptake, but nowhere near optic nerve.

Anyways, I feel like something's wrong with peripheral vision on the left.

Thanks, and also for answering all the questions during Christmas & New Year holidays!

[aliaat]

Sorry, forgot to mention: nothing on deep tendon reflexes. If anything, there normally tends to be hyPERreflexia in the knees (presented 3 yrs ago w/transverse myelitis & numerous brain lesions).