The pop-eyed look

The pop-eyed look

They may look beautiful, but big, bright eyes could be a sign of some thyroid-related disease, warns Dr Milind Naik.

Large, almond-shaped eyes are certainly a sign of beauty, but they could also be a manifestation of Thyroid Eye Disease (TED). TED is an autoimmune disease affecting the tissues around the eye, which can occur in all races and ages. In a healthy person, the amount of fat behind the eyeball is constant and the movement of the eye is normal.

But in TED, inflammatory cells lead to excess fat and fibrous tissue (scar) deposition behind the eyeball. Swelling and deposition of certain chemicals (glycosaminoglycans) causes the eye to protrude. Simply put, the tissues behind the eye enlarge, making the eye prominent. If eye muscles are involved, movement may get affected, leading to double vision.

Though in most cases, a deranged thyroid blood level is detected, TED can occur even with normal thyroid levels. TED typically has an active phase followed by a stable (inactive) phase. The active phase may last from six to 18 months, during which the patient may experience discomfort, swelling and redness around the eyes and progressive prominence of the eyeballs. 

But there’s no reason to be alarmed as reduction in vision is rare and occurs only if the optic nerve is compressed due to swelling. Double vision may occur if the eye muscles are severely affected. Treatment during this phase is aimed at reducing the immunological inflammation (active swelling), usually with the use of medications (steroids).

Once the TED has become inactive, it is time to perform corrective surgeries that will rectify the damage caused during the active stage. Surgical correction of the eye protrusion (proptosis), aligning the eye muscles to correct double vision, narrowing the eyelid apertures or simply reducing the fat pockets in the eyelids is done in this stage. The best way to decide whether you need treatment or not is by discussing it with your eye plastic surgeon (oculoplastic surgeon).

It is a common myth that control of thyroid levels or treatment with steroids will reverse the eye findings. It rarely does. Medical treatment in the ‘active’ phase merely pushes the ‘fast-forward’ button, so that you arrive at the inactive phase early, to get early surgical correction. 
(The author is oculoplastic surgeon, LV Prasad Eye Institute, Hyderabad)