Pop Eye

The Pop-Eyed Look and Your Thyroid

The Pop-Eyed Look and Your Thyroid

Dr Milind Naik, Oculoplastic Surgeon, L V Prasad Eye Institute, Hyderabad

Large, almond shaped eyes are certainly a sign of beauty, but it could also be a manifestation of Thyroid Eye Disease (TED). TED is an autoimmune disease affecting the tissues around the eye. It can occur in all races and ages.

In a normal person, the amount of fat behind the eyeball is constant and the movement of the eye is normal too. In TED, the autoimmune disorder causes inflammatory cells leading to excess fat and fibrous tissue (scar) deposited 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. This active phase can be simply compared to a house on fire. While it is on flames, the fireman (doctor) concentrates on extinguishing the fire (immune swelling) with water or fire-extinguisher (steroids). One cannot think of re-building the house while the fire is still on! In effect, the active phase may last from 6 – 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, however, 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. This can be compared to the repair carried out after the house fire is successfully controlled. 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).

Imagine your bony socket as the ice-cream cone and your eyeball as the ice-cream scoop over it. Key-hole Orbital decompression widens the bony socket (enlarges the cone) so that the eyeball (your scoop) sinks into a natural position. This surgery is performed through hidden incisions. 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. In a third of the patients, this ‘eye component’ of thyroid disease can occur even if their thyroid blood levels are normal.

To summarize, thyroid eye disease has an active and inactive phase. The active phase needs medical treatment, followed by the inactive phase when surgical treatment restores normal appearance.