What causes eye or eyelid asymmetry? Why is one eye larger or smaller than the other eye?
Asymmetrical or uneven eyes are practically normal and perhaps expected in the general population. They can be very subtle or very obvious to the patient and the observer. The eye asymmetry could become more apparent when smiling, when tired, etc, depending on the cause. When the difference between the two eyes is more obvious, it can become bothersome to the patient.
Eye size asymmetry can be caused by many factors. True eye size asymmetry (one eyeball being bigger or smaller than the other) is rare but can happen. Most commonly, the eye asymmetry is an illusion due to eyelid asymmetry (upper and/or lower eyelids), eyeball position asymmetry, and/or orbit (eye socket) asymmetry. A detailed oculoplastics exam is necessary to determine the cause and the possible treatments for asymmetrical eyes. Contact TabanMD to schedule an exam today.
Upper Eyelid Ptosis
One common cause of eye asymmetry is asymmetric upper eyelid ptosis (droopy upper eyelid), causing the eye with the droopier eyelid to appear smaller. There are various causes of upper eyelid ptosis. One of the best treatment options is droopy eyelid (ptosis) surgery.
*See disclaimer below
Before eye asymmetry due to right upper eyelid ptosis. After right upper eyelid ptosis repair with improved eye symmetry.
Before eye asymmetry due to right upper eyelid ptosis. After right upper eyelid ptosis surgery with improved eye symmetry.
Upper Eyelid Retraction
Another cause of eye size asymmetry is upper eyelid retraction (the upper eyelid is higher than normal) where the eye appears bigger than the other eye. Upper eyelid retraction could be congenital/inherited, due to thyroid eye disease, postsurgical, etc. In many cases, the best treatment is upper eyelid retraction surgery.
Before eye asymmetry due to mild right upper eyelid retraction. After right upper eyelid retraction surgery with improved eye symmetry.
Before obvious eye asymmetry due to left upper eyelid retraction and right upper eyelid ptosis. After left upper eyelid retraction surgery and right upper eyelid ptosis surgery with improved symmetry.
Lower Eyelid Retraction
If one eye lower eyelid is lower than the other eye, then that eye would appear larger. There are various causes of lower eyelid retraction including congenital/inherited, post-blepharoplasty eyelid retraction, and post skin cancer surgery. Treatment usually involves elevating the lower eyelid, through hidden transconjunctival approach with possible midface/soof lift and/or internal spacer graft.
Eye asymmetry due to right lower eyelid retraction with sclera show.
After – bilateral lower eyelid retraction surgery, right side greater, with improved eye symmetry.
Before obvious eye asymmetry due to severe left lower eyelid retraction. After left lower eyelid retraction with improved eye symmetry.
If one eyebrow is higher or lower than the other, that can make the eyes look asymmetrical. Eyebrow position is determined by genetics, facial bony structure, muscle/nerve function, and underlying eyelid. For instance, a droopy upper eyelid (ptosis) can cause the same side eyebrow to elevate in order to assist lift the droopy eyelid.
Before eye asymmetry due to uneven eyebrows with right side higher. After asymmetric botox injection to make brows evener.
Middle age woman, with both eyelid and eyebrow asymmetry, underwent asymmetric botox injection to create more symmetric eyes.
If there is more hollowness around one eye, that can cause the eyes to look asymmetric. Treatment could be via non-surgical eyelid filler injection or fat injection. Learn more about eyelid filler injection.
Before eye asymmetry due to left upper eyelid hollowness. After left upper eyelid filler injection with improved eye symmetry.
41 year old male, complained of eye asymmetry and looking tired which is due to left upper eyelid ptosis (droopy upper eyelid) and upper eyelid hollowness along with under eye bags. He underwent internal left upper eyelid ptosis surgery and bilateral upper eyelid-brow filler injection, along with transconjunctival lower blepharoplasty with fat repositioning. No skin was removed from any of the eyelids. Before and 6 weeks after cosmetic eyelid surgery and upper eyelid filler injection photos are shown. (After photo is a selfie.)
Asymmetric eyelid contours can also lead to eye asymmetry as this photo depicts.
Asymmetric eyes due to uneven lower eyelid contours and positions.
Video showing young woman with upper eyelid asymmetry who undergoes right upper blepharoplasty and left upper eyelid filler injection with improved upper eyelid symmetry.
Eyeball Position or Orbit Asymmetry
If one eyeball is more bulging (protruding) than the other eyeball, it will make the eye appear larger. There are various causes of bulgy eyes including genetic/inherited, Graves thyroid eye disease, shallow eye socket, and flat upper cheekbone. Bulging eye can be treated via orbital decompression surgery to make the eyeball go back.
Eye asymmetry due to bulging eyes, right side worse. After bilateral orbital decompression, right side more, and lower eyelid retraction.
Enophthalmos (sunken eye)
Another related cause of eye asymmetry is if one eyeball is more sunken than the other eyeball (enophthalmos), making the eye appear smaller. There are various causes of enophthalmos including genetic/inherited, prior orbital blowout fracture, and silent sinus syndrome. The cause of enophthalmos needs to be determined and then treatment could be considered which could include orbital implant placement to push the eyeball forward.
Eye asymmetry due to left enophthalmos or sunken eye from orbital fracture making left eye appear smaller. After left orbital implant placement with an improved eye.
Obvious eye asymmetry due to the right sunken eye. After right orbital implant placement with improved eye.
If the orbits (bony eye socket) are positioned differently in the facial bone (skull), then that can cause subtle to very obvious eye asymmetry with one eye being higher or lower than the other eye. Treatment could consist of altering the eyelid position (through eyelid surgery) and/or eyeball position (through customized orbital decompression and/or orbital implant). Expert evaluation is needed along with a CT scan of orbits for proper assessment and treatment.
Eye asymmetry due to right orbit and eyeball higher than the left eye.
Eye asymmetry due to right eyeball higher than the left. After right customized orbital decompression to lower right eyeball, with improved eye symmetry.
55-year-old female, complained of eye asymmetry with right eye lower than left eye. She underwent right orbital floor implant and left upper eyelid filler injection to improve her eye symmetry. Before and 3 months after eye plastic surgery photos are shown.
*Disclaimer: Results vary from patient to patient. Results are not guaranteed.
Eye asymmetry with right eyeball more bulging and lower than left eyeball and orbit.
EYEBALL size asymmetry causes (rare): microphthalmos, buphthalmos, high myopia.
28 year old beautiful female model, complained of eye asymmetry, especially when smiling, with left eye getting smaller. She received botox injection to left eyelid with improved eye symmetry when smiling. Photos depict resting position and smiling, with and without botox.