Correlation between TGF-beta1 in tears and corneal haze following LASEK and epi-LASIK.
OBJECTIVE
To compare the incidence and degree of corneal haze formation following laser subepithelial keratomileusis (LASEK) and epithelial laser in situ keratomileusis (epi-LASIK), and examine its correlation with tear film transforming growth factor-beta1 (TGF-beta1) levels.


METHODS
This prospective, interventional, clinical trial included 20 eyes (20 patients) randomly assigned to undergo LASEK or epi-LASIK. The level of TGF-beta1 in tear fluid was measured preoperatively and 1, 3, and 5 days postoperatively. Corneal haze was graded at 1 and 3 months after surgery, and the relationship with TGF-beta1 levels was determined.


RESULTS
Mean preoperative spherical equivalent refraction was -4.50 +/- 1.44 diopters (D) (range: -1.50 to -6.00 D) for LASEK eyes and -4.90 +/- 1.26 D (range: -1.75 to -6.00 D) for epi-LASIK eyes. Although mean corneal haze scores at 1 month were significantly higher in LASEK-treated eyes than in epi-LASIK treated eyes (P=.031), these scores were similar at 3 months (P=.608). Tear fluid TGF-beta1 levels were similar in LASEK and epi-LASIK eyes before surgery (P=.458) and significantly higher in the LASEK group at 1, 3, and 5 days postoperatively (P=.015, P=.023, and P=.039, respectively). A positive correlation was noted between tear TGF-beta1 levels on the first postoperative day and the degree of corneal haze at 1 month (r=0.501, P=.016).


CONCLUSIONS
Less corneal haze was noted after epi-LASIK than LASEK. A positive correlation between corneal haze and tear fluid TGF-beta1 levels on the first postoperative day suggest a possible mechanism for the observed difference.
Long
Qin
Q
Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academic of Medical Science, Medical College, Peking, China.
Chu
Renyuan
R
Zhou
Xingtao
X
Dai
Jinhui
J
Chen
Chongda
C
Rao
Srinivas K
SK
Lam
Dennis S C
DS
D000328:Adult; D003318:Corneal Opacity / Q000209:etiology* / Q000378:metabolism; D005260:Female; D006801:Humans; D015994:Incidence; D049008:Keratectomy, Subepithelial, Laser-Assisted; D020731:Keratomileusis, Laser In Situ; D008297:Male; D009216:Myopia / Q000601:surgery*; D011183:Postoperative Complications; D011446:Prospective Studies; D013666:Tears / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D053773:Transforming Growth Factor beta1
C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1