DRY EYES & MGD

www.ncbi.nlm.nih.gov/pubmed/16209440

CONCLUSIONS:
The human comeal stroma typically heals after LASIK in a limited and incomplete fashion; this results in a weak, central and paracentral hypocellular primitive stromal scar that averages 2.4% as strong as normal comeal stroma. Conversely, the LASIK flap wound margin heals by producing a 10-fold stronger, peripheral hypercellular fibrotic stromal scar that averages 28.1% as strong as normal comeal stromal, but displays marked variability.

www.srmc.amedd.army.mil/assets/home/lasik.html

"In the Army, LASIK is can be a disqualifying factor for military specialties like. Special Forces, Ranger, HALO, etc."

www.ncbi.nlm.nih.gov/pubmed/22480669

"Objective: To investigate the relationship between eye injury and laser in-situ keratomileusis (LASIK) surgery in military personnel.Methods: This retrospective study collected the data from 27 evacuation hospitals of Chinese army. All medical records of eye injuries in military personnel admitted to the 27 hospitals between January 2006 and December 2010 were reviewed. Patients'detailed information was analyzed, including the injury time, place, type, cause, as well as examination, treatment and outcome.Results: There were 72 eye-injured patients who had been treated by LASIK before. The incidence was rising year by year. ...Conclusion: There is a high risk of potential traumatic flap problems after LASIK and it is not recommended in army service."

usmilitary.about.com/od/theorderlyroom/l/bllasersurgery.htm

"Currently, the Air Force allows free laser eye surgery (PRK) only to those in a limited number of jobs (AFSC)."

"Navy SEALs and divers are allowed to receive PRK, but not LASIK. "LASIK continues to be disqualifying with no waiver recommended for SEALs and divers," he said."

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William Trattler, MD and Scott Barnes, MD published an article in the July, 2008 issue of Current Opinion in Ophthalmology,1 which states:

"At Fort Bragg, North Carolina, the Army surgeons have moved to 100% surface ablation in the past 2 years; the five known traumatic flap dislocations (out of 2500 procedures) due to 'typical' soldier activities contributed to this change but not as much as an analysis of the visual outcomes. A review of the 28,000 procedures has shown that soldiers with PRK or LASEK have a 20% greater chance of achieving an uncorrected visual acuity of 20/15 or better than soldiers with a similar level of refractive error undergoing LASIK."

Mr. Wiggles has described several cases of flap dislodgement, I had one too when a patient 4 years after Lasik decided to kiss a sleeping Doberman goodnight. The dog bite took off her lid and moved her flap. The lid was the hard thing to fix. The flap was cleaned and replaced and stitched and 1 month later her vision was 20/20 again.

All flap late dislocation reports I have seen reported have been made with blade microkeratomes. Larger Intralase flaps definitely bind down better and can be very difficult to lift for retreatments later.

In spite of the potential for flap dislocation (with keratomes) Lasik was studied on US Rangers and found to be safe in simulated combat and not only was Lasik permitted but also performed for free in the US military.

www.srmc.amedd.army.mil/assets/home/lasik.html
usmilitary.about.com/od/theorderlyroom/l/bllasersurgery.htm

Finally dealing with the issue of permanent "weakness" or harm following Laser eye surgery - I still would like to see some actual references (please cite them so that I can reference directly) to indicate that this procedure leaves the cornea permanently weakened.

In this case, the flap displaced as a result of a punch to the eye in a 28-year-old-woman who had undergone LASIK four years earlier. Five days after the traumatic incident, she came in complaining of diminished vision. The patient’s uncorrected visual acuity, which had been 20/20 in the eye after LASIK, had dropped to 20/60.

Seven years after uneventful laser in situ keratomileusis (LASIK), a 48-year-old woman presented one week after being hit with an iron cord with blurry vision, pain, and irritation. The injury resulted in traumatic flap dislocation, epithelial ingrowth, and macrostriae. Following epithelial removal, the flap was refloated and repositioned.

"A 29-year-old man was treated after air bag injury that occurred 48 months after LASIK. Examination revealed corneal flap dislocation, with severe folds and flap edema. Preoperative visual acuity was finger counting at 1 m. Visual acuity was 20/400 24 hours after repositioning the corneal flap"

A 23-year-old lady presented in August 2002, with complaints of irritation, watering and defective vision in the right eye following an accidental fingernail trauma from her 6-month-old child.
Her records showed that she had undergone bilateral simultaneous myopic LASIK elsewhere 4 years earlier for a preoperative myopia of 6 DSph

OK Anonymous let's have the references of the "plenty of references". What exactly do the references state that is in disagreement with what I have stated ? Does the cornea rupture on trauma (never seen this and I am in the business of fixing corneas and never seen a reference or case report - and I do read and contribute to the literature as a writer, editor and reviewer.

Would be useful to understand what it is you are trying to get at. Is the logic that because tissue is removed it is wrong ? Or is it because the cornea is thinned it is wrong ? If that is the contention what is the impact of thinning the cornea that makes it wrong ?

There are patients out there with thinning diseases of the cornea - keratoconus. Even their corneas do not split open in spite of being extremely thin. what is the impact of having a cornea thinned ? THe only one I am aware of is ectasia.

Corneas have been thinned out for over a century for numerous reasons and this has been done mechanically with no long term sequelae. Lasik is more than 20 years old and essentially involves the same thing but with sophisticated lasers.

50 million people worldwide have had laser eye surgery. Sadly UK seems to have a disproportionate of poor outcomes reflective of the type of providers in practice which sadly many of you have entrusted with your care.

There're plenty of publications disagreeing with you - as I do!

If the cornea is burned away then of course it's weakened as it's thinner and won't grow back!

Thank you the supportive posts.

Limits of corneal thickness ranges between 250 and 300(preferable) microns under a corneal flap. This is to avoid ectasia (bulging), although the risk of this condition depends on the elasticity of the cornea.

Surgery does not really leave the cornea permanently weakened. Much depends on how much is removed. Trauma studies on cadaver eyes that have had Lasik, still rupture under the muscle insertions just like a normal eye. The cornea was not involved. The area of insertion on the eye is the weakest spot.

how can any surgery that leaves the cornea permanently weakened be justifiable? what happened to doctors doing no harm?

In the bus, we appreciate your presence and advice.

Something less relevant to MGD, more about thin corneas.

What actual size should be the cornea where by its too thin, and consider to be a risk?