You may read all Lasik Eye Surgery Problems like dry eyes, halos and slipped flap in this post. You can leave a comment for this post and you can share your LASIK story if you experienced it.
Vision loss due to infection
On October 10, 2006, WebMD reported on a peer-reviewed study in the Archives of Ophthalmology in which statistical analysis revealed that vision loss risk as a result of an infection for contact lens wearers is higher than vision loss risk as a result of an infection from LASIK.
Daily contact lens wearers have a 1-in-2,000 chance of significant vision loss. The researchers calculated the risk of significant vision loss consequence of LASIK surgery to be closer to 1-in-10,000 cases.
The term “higher-order aberrations” are visual problems that require special testing for diagnosis and are not corrected with normal spectacles (eyeglasses). These aberrations include ‘starbursts’, ‘ghosting’, ‘halos’ and others. Some patients describe these symptoms post-operatively and associate them with the LASIK technique including the formation of the flap and the tissue ablation. The advancement of the LASIK technology has reduced the risk of clinically significant visual impairment after surgery. There is a correlation between pupil size and aberrations. This correlation may be the result of irregularity in the corneal tissue between the untouched part of the cornea and the reshaped part. Daytime post-LASIK vision is optimal, since the pupil size is smaller than the LASIK flap. However, at night, the pupil may dilate such that light passes through the edge of the LASIK flap which gives rise to aberrations. LASIK and PRK may induce spherical aberration if the laser under corrects as it moves outward from the centre of the treatment zone, especially when major corrections are made. Others propose that higher order aberrations are present preoperatively. They can be measured in micrometers (µm) whereas the smallest laser beam size approved by the FDA is about 1000 times larger, at 0.65 mm. In situ keratomileusis effected at a later age increases the incidence of corneal higher-order wavefront aberrations. These factors demonstrate the importance of careful patient selection for LASIK treatment.
Some people experience dry eyes following surgery. Although it is usually temporary it can develop into dry eye syndrome. Underlying conditions with dry eye such as Sjögren’s syndrome are considered contraindications to Lasik. Treatments include artificial tears, prescription tears and punctal occlusion. Punctal occlusion is accomplished by placing a collagen or silicone plug in the tear duct, which normally drains fluid from the eye. Some patients complain of ongoing dry eye symptoms despite such treatments and dry eye symptoms may be permanent.
Some post-LASIK patients see halos and starbursts around bright lights at night. At night, the pupil may dilate to be larger than the flap leading to the edge of the flap or stromal changes causing visual distortion of light that does not occur during the day when the pupil is smaller. The eyes can be examined for large pupils pre-operatively and the risk of this symptom assessed.
Complications due to LASIK have been classified as those that occur due to preoperative, intraoperative, early postoperative, or late postoperative sources: According to the UK National Health Service complications occur in fewer than 5% of cases.
- Flap Complications – The incidence of flap complications is about 0.244%. Flap complications (such as displaced flaps or folds in the flaps that necessitate repositioning, diffuse lamellar keratitis, and epithelial ingrowth) are common in lamellar corneal surgeries but rarely lead to permanent loss of visual acuity. The incidence of these microkeratome-related complications decreases with increased physician experience.
- Slipped Flap – is a corneal flap that detaches from the rest of the cornea. The chances of this are greatest immediately after surgery, so patients typically are advised to go home and sleep to let the flap adhere and heal. Patients are usually given sleep goggles or eye shields to wear for several nights to prevent them from dislodging the flap in their sleep. A short operation time may decrease the chance of this complication, as there is less time for the flap to dry.
- Flap interface particles – are a finding whose clinical significance is undetermined. Particles of various sizes and reflectivity are clinically visible in about 38.7% of eyes examined via slit lamp biomicroscopy and in 100% of eyes examined by confocal microscopy.
- Diffuse lamellar keratitis – an inflammatory process that involves an accumulation of white blood cells at the interface between the LASIK corneal flap and the underlying stroma. It is known colloquially as “sands of Sahara syndrome” because on slit lamp exam, the inflammatory infiltrate appears similar to waves of sand. The USAeyes organisation reports an incidence of 2.3% after LASIK. It is most commonly treated with steroid eye drops. Sometimes it is necessary for the eye surgeon to lift the flap and manually remove the accumulated cells. DLK has not been reported with photorefractive keratectomy due to the absence of flap creation.
- Infection – the incidence of infection responsive to treatment has been estimated at 0.4%.
- Post-LASIK corneal ectasia – a condition where the cornea starts to bulge forwards at a variable time after LASIK, causing irregular astigmatism. the condition is similar to keratoconus.
- Subconjunctival Hemorrhage – A report shows the incidence of subconjunctival hemorrhage has been estimated at 10.5%.
- Corneal Scarring – or permanent problems with cornea’s shape making it impossible to wear contact lenses.
- Epithelial Ingrowth – estimated at 0.1%.
- Traumatic Flap Dislocations – Cases of late traumatic flap dislocations have been reported up to seven years after LASIK.
- Retinal Detachment: estimated at 0.36 percent.
- Choroidal Neovascularization: estimated at 0.33 percent.
- Uveitis: estimated at 0.18 percent.
- For Climbers – Although the cornea usually is thinner after LASIK, because of the removal of part of the stroma, refractive surgeons strive to maintain the maximum thickness to avoid structurally weakening the cornea. Decreased atmospheric pressure at higher altitudes has not been demonstrated as extremely dangerous to the eyes of LASIK patients. However, some mountain climbers have experienced a myopic shift at extreme altitudes.
- Late Postoperative Complications – A large body of evidence on the chances of long-term complications is not yet established and may be changing due to advances in operator experience, instruments and techniques.Potential best vision loss a year after the surgery regardless of use of glasses.