Temporary doubled vision or ghosting images during
the normal six-month healing period after conventional or wavefront custom Lasik tend to be caused by an irregularity in the cornea.
Monocular or Binocular Diplopia
If the ghosting occurs with only one eye open it is called monocular
diplopia and is usually related to edema, astigmatism, epithelial defect, or incision wound healing. If the ghosting
occurs only when both eyes are open, the problem may be binocular
diplopia, an aberration in the alignment of the two eyes.
Surgery Induced
On more rare occasions, ghosting can be due to an irregularity
in the application of the excimer laser energy used for conventional or custom wavefront Lasik, Bladeless Lasik, PRK, LASEK, and Epi-Lasik. Examples of complications due to irregularity in
the application of excimer energy would be decentered ablation or central islands.
If the patient had RLE or P-IOL, the ghosting can be caused by a misaligned lens or incision
wound healing.
Edema, Epithelial Defect, Astigmatism, Dry Eyes
Dry eyes will almost always exacerbate ghosting, and can be
the sole cause of the ghosting.
Probably the most common cause of temporary surgery-induced ghosting
is edema. All types of refractive surgery are an insult to the eye
and swelling of the cornea is a common response. As the eye heals,
edema is reduced and the corneal irregularity is resolved. With
the resolution of the edema, the ghosting disappears. Edema seems
to be most pronounced with PRK and Bladeless Lasik, although all
eye surgery can cause edema.
Epithelial defect causes ghosting primarily with PRK, LASEK,
and Epi-Lasik, but the process of creating a corneal flap for Lasik
and Bladeless Lasik can damage the epithelium too. Fortunately the
epithelial cells are the fastest reproducing cells in the human
body and within a few days to weeks can cover the cornea, thicken,
and smooth to preoperative levels.
Longer-term ghosting may be caused by astigmatism, which can
cause multiple focal points. Astigmatism after surgery may be preoperative
astigmatism that was not fully eliminated. With Lasik, Bladeless
Lasik, PRK, LASEK, and Epi-Lasik, it is possible that astigmatism
was induced during surgery by an inaccurate laser ablation. P-IOL
and RLE require an incision at the edge of the cornea to insert
the lens. This incision and subsequent stitching may induce astigmatism.
An easy test for astigmatism is to put a small hole through an
index card then look through that hole with one eye while covering
the other eye. Be sure to do this in a dimly lit room. As you move
the hole around you will probably notice that the ghosting is gone.
Worse in Low Light
Ghosting is often worse in low light environments and can disappear
completely in well lit environments. When you are in a well-lit
environment, the pupil is smaller and is not letting the light that
is passing through the irregular component of your cornea reach
the retina. The multiple focal points are still there; they are
just not reaching the retina and being "seen".
Central Islands
Central
islands are formed when an area of the Lasik, Bladeless Lasik,
PRK, LASEK, or Epi-Lasik treatment zone does not receive the full
amount of laser energy. Wrinkles in the flap (striae)
may provide multiple ghost images. Central islands are much more
rare than astigmatism, edema, or epithelial defect.
Check with your doctor to determine the exact nature of your
problem. If the ghosting is caused by your remaining astigmatism,
ask your doctor about the possibility of an enhancement to eliminate
your residual astigmatism. Or just see if a good pair of glasses
or contacts do the trick. If ghosting is caused by swelling, you
need to wait for healing. Since dry eyes can cause and exacerbate
ghosting, you may want to visit an article on dry eye treatment. Depending upon the nature of the striae,
a flap lift may be necessary. We have an article on striae
resolution too.
Looking For Best Lasik Surgeon?
If you are ready to choose a doctor to be evaluated for conventional
or custom wavefront Lasik, Bladeless Lasik, PRK, or any refractive surgery procedure, we recommend you consider a doctor who has been evaluated and certified by the USAEyes nonprofit organization.
Locate a USAEyes Evaluated & Certified Lasik Doctor.
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