THYROID EYE DISEASE
Graves’ ophthalmopathy or thyroid eye disease is an autoimmune disease. This means that, due to unknown causes, the immune system produces antibodies that simultaneously attack the thyroid gland, the structures surrounding the eyes and, occasionally, the skin on the front of the legs. Each of these sites is independently affected. The eyes and surrounding tissues are located within the orbit. The orbit is an inextensible cavity surrounded by bone, so when these tissues are attacked by the antibodies, they become inflamed and enlarged. The orbit cannot accommodate this muscle enlargement and the eyes are pushed outward. The muscles that lift the eyelids are closely connected to those that move the eyes, and are also affected by this disease. This causes retraction of the eyelids, especially the upper eyelid, which is the most prevalent effect in this condition. This, together with the advancement of the eyes, produces the characteristic “bulging eyes” appearance.
THIS DISEASE HAS TWO STAGES.
- Active stage: It occurs when the immune system produces antibodies, which leads to inflammation of the orbital contents. It lasts 6 to 12 months and resolves on its own. The use of corticosteroids during this stage may help decrease the inflammation of the muscles. Oral Corticosteroids have general adverse effects. Sometimes corticosteroids can be injected into the lower eyelid to gain access to the orbit and thus decrease the inflammation which is typical of this disease, with minimal overall effects. Occasionally they can also be used intravenously, especially for the treatment of cases with more severe inflammation. There is a new treatment that can markedly reverse the effects of this disease, when indicated in the acute stage. It is a drug called Tepezza (teprotumumab), which prevents the antibodies that cause this disease from binding to the affected cells. It was approved by the US FDA in January 2020 and we hope to have this treatment available in Argentina in the future.
- The second stage begins after the end of inflammation and is called the “scarring” or “residual” stage. In this stage, the changes produced in the eyes usually improve partially or completely. Surgical treatments are intended to correct the alterations that persist after the inflammation has subsided. Before planning the surgery, it is necessary to wait at least 6 months to verify that the situation is stable. The only exception are the rare cases in which there is compression of the optic nerve and decreased vision, where treatment should be performed quickly.
SURGICAL REHABILITATION
Traditionally, the correction of the alterations caused by this disease required a series of surgical stages or steps that will be detailed below. In the past few years, in order to reduce the time and cost of rehabilitation in multiple stages, we have started to perform orbital and eyelid surgery bilaterally and simultaneously. This experience is published in a scientific paper: Bernardini, F. P., Skippen, B., Zambelli, A., Riesco, B., & Devoto, M. H. (2018). Simultaneous Aesthetic Eyelid Surgery and Orbital Decompression for Rehabilitation of Thyroid Eye Disease: The One-Stage Approach. Aesthet Surg J, 38(10), 1052-1061. doi:10.1093/asj/sjy014
ORBITAL DECOMPRESSION:
The first surgery to be performed, if necessary, is orbital decompression. Orbital decompression basically consists of modifying the bony walls of the orbit, adjusting the bones in such a way that the fat and muscle content that has increased in volume due to the disease can be accommodated. Surrounding the orbits are the paranasal sinuses, which are cavities that have no role in the body, and can be used as a space to expand the orbit. In this way we can access the medial orbital wall, the orbital floor and the external orbital wall through the conjunctiva, without making incisions, on the skin but rather by making a small incision in the external angle of the eyes. This allows us to modify the three walls, excluding the orbital roof, which is used only in exceptional cases, without visible incisions. This surgery is performed with magnification and light through a small space that allows us to reach the most posterior part of the orbit and create the necessary space so that, once the surgery is finished, the eyes can retreat as predicted. Occasionally, at the end of an orbital decompression procedure, a drain is placed in order to evacuate the blood that may be produced after surgery and to minimize bruising and the risks of the operation. This drain is removed after 24 hours. Afterwards, the patient must rest for 2 to 3 days and apply cold compresses. After this period, the patient can resume their normal routine.
COMPLICATIONS OF THIS SURGERY ARE RARE:
All surgeries of or surrounding the eyes carry some degree of risk to them. In orbital decompression, the risk of decreased or lost vision is estimated to be less than 1 in 1000 operations The most frequent and uncomfortable complication for the patient is double vision caused by the surgery. The incidence of this complication varies depending on the movement of the eyes before surgery and the size of the muscles when seen in a CT scan. If the patient has very thick or asymmetric muscles between both orbits and has difficulty with eye movements, their chances of having double vision after the operation are greater than 20 %. If the patient has thin muscles with good movement in all directions preoperatively, the incidence of postoperative double vision is around 2 to 5 % depending on the techniques used. To minimize the possibility of postoperative double vision, the orbital floor can be protected, since the removal of the entire orbital floor results in an increase in vertical double vision. If the patient presents double vision after decompression surgery, it can be corrected through strabismus surgery or with prisms after a one-month wait period. Another very rare complication is sinusitis, which can be resolved with antibiotics or ENT surgery.
STRABISMUS CORRECTION:
The second step in the surgical rehabilitation of Graves’ disease is precisely the correction of strabismus, if it is present. This surgery is usually performed by ophthalmologists specialized in strabismus and neuro-ophthalmology, since they are experts in knowing the degree of modification in the muscle insertions needed to correct double vision. Since this disease affects the thickness and elasticity of the muscles, it is not always possible to correct double vision in all gaze positions. Therefore, the main goal of the surgery is to remove double vision when the patient looks straight ahead and down, which are the most frequent gaze positions in daily life.
RECONSTRUCTIVE AND ESTHETIC EYELID SURGERY:
The last phase in the surgical rehabilitation of Graves’ ophthalmopathy, and often the only one necessary as most cases are usually mild, consists of eyelid surgery. The most frequent manifestation of Graves’ disease is upper eyelid retraction, where the eye appears very exaggeratedly open and gives the appearance of greater protrusion. When a patient presents eyelid retraction and the sclera (the white) is visible above the eye, it creates a very conspicuous and disfiguring appearance. Eyelid retraction surgery is performed with local anesthesia and a sedative, in a comfortable setting, making it possible to adjust the height and shape of the eyelid so that it is symmetrical in its position and shape with the opposite side. Because the eyelids are delicate structures that are very close to each other, it is not always possible to correct them to complete symmetry, and it is often necessary to perform more than one procedure to achieve the desired result. However, the results are usually very good and significantly correct the preoperative appearance. Recovery from eyelid surgery usually lasts approximately one week. During the first three days, patients should apply cold compresses, and from the fourth to the seventh day they will notice swelling but will be able to continue with their usual activities. Fat prolapse (bags) may also be corrected during an eyelid retraction correction procedure. In the upper eyelids, this usually affects the bags next to the nose, and the fat under the eyebrows may also be thickened. This fat that has increased in size during the disease can be thinned in the same surgical procedure in order to achieve a more natural shape. Lower eyelid retraction, when mild, can be corrected with a transconjunctival approach (without skin incisions), which allows access to the eyelid retractors, thin structures that connect the muscles that move the eyes to the eyelid. By modifying the position of these retractors, it is possible to correct the lower eyelid retraction and eliminate the scleral exposure (white under the eye) which also contributes to the appearance of a protruding eye. Lower eyelid retraction is not only a cosmetic problem, but it is usually associated with the inability to fully close the eye and can cause keratitis. Therefore, surgery is usually indicated to improve lubrication of the eye and prevent it from becoming dry. During retraction correction surgery, any esthetic alteration produced during the disease is usually also corrected. Most frequently, this means removing the fat bags that usually prolapse or protrude through the eyelid, associated with Graves’ ophthalmopathy. This whole process of surgical rehabilitation, which requires several stages, usually lasts approximately 6 months to 1 year, because it is convenient to wait between one stage and the other until there is no more inflammation. The final result, after these stages are concluded, is usually extremely favorable for the patient and very gratifying as they can recover or rehabilitate their alterations to a great extent.
BEFORE AND AFTER
case 1
BEFORE:
C presented with exophthalmos, eyelid retraction and lower eyelid bags. Surgical repair was recommended in a single operation, with bilateral orbital decompression, retraction surgery of both upper eyelids and bilateral upper and lower blepharoplasty.
after:
3 months after surgery, she recovered the position and esthetics of her gaze.
case 2
BEFORE:
Nelly had thyroid eye disease with left exophthalmos, retraction and bags in lower eyelids.
after:
Left orbital decompression, left upper eyelid retraction repair and blepharoplasty of both lower eyelids were performed in a single procedure.
case 3
BEFORE:
Natalia presented with bilateral exophthalmos caused by this disease.
after:
After her bilateral orbital decompression and upper and lower blepharoplasty in a single procedure.
