School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan250062, China
Department of Ophthalmology, the Second People's Hospital of Jinan, Jinan 250001, China
Objective: To study the effects of small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK) on corneal densitometry (CD) after refractive correction for myopia. Methods:This was a retrospective non-randomized cohort study. Ninety patients (172 eyes) underwent refractive surgery from July 2016 to November 2017, in which 45 patients (86 eyes) underwent SMILE and the other 45 patients (86 eyes) underwent FS-LASIK. The CD data was calculated automatically by the Pentacam system before surgery and 3 months after surgery. For CD analysis, the average CD in the three concentric radial zone centered on the apex of the cornea (0-2 mm, 2-6 mm, 6-10 mm diameters) were divided into three layers that were defined according to different corneal depths (the anterior 120 μm as the 1st layer,the posterior 60 μm as the 3rd layer, and the center part between them as the 2nd layer). The overall CD of the cornea was also measured. A covariance analysis was used to compare the CD between the two groups,and a Wilcoxon test was used to compare the CD within groups. A Spearman test was used to analyze the relationship between the change in CD and CCT, IOP, corneal curvature and SE. Results: In the SMILE group, CD after surgery was lower than before surgery and differences were significant (all P<0.05), except for the 2nd layer in the 0-2 mm range (Z=-1.956, P=0.051). In the FS-LASIK group, CD after surgery was lower than before surgery and differences were significant (all P<0.05). Except for the 0-2 mm 1st and 3rd layer (Z=-2.927, P=0.003; Z=-2.261, P=0.024), the diffrences were not significant for other radial zone and layers. When the changes in CD were compared between the two groups, there were no statistically significant differences for the 3rd layer in the 6-10 mm range (F=1.808, P=0.181), the 3rd layer (F=3.281, P=0.072), and the total layer (F=3.666, P=0.057). The rest had statistically significant differences (all P<0.05), and the CD of the SMILE group was lower than that in the FS-LASIK group. Conclusions: Both SMILE and FS-LASIK decrease corneal densitometry, and they have similar effects on total corneal densitometry.
Otri AM, Fares U, Al-Aqaba MA, et al. Corneal densitometry as an indicator of corneal health. Ophthalmology, 2012, 119(3):501-508. DOI: 10.1016/j. ophtha.2011.08.024.
[3]
Orucoglu F, Talaz S, Aksu A, et al. Corneal densitometry evaluation in archipelago keratitis. Int Ophthalmol, 2014, 34(1):99-102. DOI: 10.1007/s10792-013-9736-4.
05
-0458.
[19]
Cankaya AB, Tekin K, Kiziltoprak H, et al. Assessment of corneal backward light scattering in the healthy cornea and factors affecting corneal transparency. Jpn J Ophthalmol, 2018,62(3): 335-341. DOI: 10.1007/s10384-018-0584-7.
[13]
Daxer A, Misof K, Grabner B, et al. Collagen fibrils in the human corneal stroma: structure and aging. Invest Ophthalmol Vis Sci, 1998, 39(3): 644-648.
Poyales F, Garzón N, Mendicute J, et al. Corneal densitometry after photorefractive keratectomy, laser-assisted in situ keratomileusis, and small-incision lenticule extraction. Eye(Lond), 2017, 31(12): 1647-1654. DOI: 10.1038/eye.2017.107.
[16]
Erie JC, Nau CB, McLaren JW, et al. Long-term keratocyte deficits in the corneal stroma after LASIK. Ophthalmology,2004, 111(7): 1356-1361. DOI: 10.1016/j.ophtha.2003.10.027.
[17]
Stramer BM, Zieske JD, Jung JC, et al. Molecular mechanisms controlling the fibrotic repair phenotype in cornea: implications for surgical outcomes. Invest Ophthalmol Vis Sci, 2003, 44(10):4237-4246. DOI: 10.1167/iovs.02-1188.
[18]
Kim JY, Kim MJ, Kim TI, et al. A femtosecond laser creates a stronger flap than a mechanical microkeratome. Invest Ophthalmol Vis Sci, 2006, 47(2): 599-604. DOI: 10.1167/iovs.
[4]
Alnawaiseh M, Rosentreter A, Prokosch V, et al. Changes in corneal densitometry in patients with fuchs endothelial dystrophy after endothelial keratoplasty. Curr Eye Res, 2017,
42
(2): 163-167. DOI: 10.3109/02713683.2016.1146774.
[5]
Luceri S, Parker J, Dapena I, et al. Corneal densitometry and higher order aberrations after bowman layer transplantation:1-year results. Cornea, 2016, 35(7): 959-966. DOI: 10.1097/ICO.0000000000000860.
[20]
Boote C, Dennis S, Newton RH, et al. Collagen fibrils appear more closely packed in the prepupillary cornea: optical and biomechanical implications．Invest Ophthalmol Vis Sci, 2003,44(7): 2941-2948.
05
-0458.
[19]
Cankaya AB, Tekin K, Kiziltoprak H, et al. Assessment of corneal backward light scattering in the healthy cornea and factors affecting corneal transparency. Jpn J Ophthalmol, 2018,62(3): 335-341. DOI: 10.1007/s10384-018-0584-7.
[6]
Elflein HM, Hofherr T, Berisha-Ramadani F, et al.Measuring corneal clouding in patients suffering from mucopolysaccharidosis with the Pentacam densitometry
Boote C, Dennis S, Newton RH, et al. Collagen fibrils appear more closely packed in the prepupillary cornea: optical and biomechanical implications．Invest Ophthalmol Vis Sci, 2003,44(7): 2941-2948.
[7]
Alnawaiseh M, Zumhagen L, Wirths G, et al. Corneal densitometry, central corneal thickness, and corneal central-to-peripheral thickness ratio in patients with fuchs endothelial
Lopes B, Ramos I, Ambrósio R. Corneal densitometry in keratoconus. Cornea, 2014, 33(12): 1282-1286. DOI: 10.1097/ICO.0000000000000266.
[9]
Kim BZ, Jordan CA, McGhee CN, et al. Natural history of corneal haze after corneal collagen crosslinking in keratoconus using Scheimpflug analysis. J Cataract Refract Surg, 2016,
42
(7): 1053-1059. DOI: 10.1016/j.jcrs.2016.04.019.
[10]
Pircher N, Pachala M, Prager F, et al. Changes in straylight and densitometry values after corneal collagen crosslinking. J Cataract Refract Surg, 2015, 41(5): 1038-1043. DOI: 10.1016/j.jcrs.2014.07.043.
[11]
Takacs AI, Mihaltz K, Nagy ZZ. Corneal density with the Pentacam after photorefractive keratectomy. J Refract Surg,2011, 27(4): 269-277. DOI: 10.3928/1081597X-20100618-02.
[12]
Boulze-Pankert M, Dariel R, Hoffart L. Corneal Scheimpflug densitometry following photorefractive keratectomy in myopic eyes. J Refract Surg, 2016, 32(11): 788-791. DOI: 10.3928/1081597X-20160720-02.
[13]
Daxer A, Misof K, Grabner B, et al. Collagen fibrils in the human corneal stroma: structure and aging. Invest Ophthalmol Vis Sci, 1998, 39(3): 644-648.
Poyales F, Garzón N, Mendicute J, et al. Corneal densitometry after photorefractive keratectomy, laser-assisted in situ keratomileusis, and small-incision lenticule extraction. Eye(Lond), 2017, 31(12): 1647-1654. DOI: 10.1038/eye.2017.107.
[16]
Erie JC, Nau CB, McLaren JW, et al. Long-term keratocyte deficits in the corneal stroma after LASIK. Ophthalmology,2004, 111(7): 1356-1361. DOI: 10.1016/j.ophtha.2003.10.027.
[17]
Stramer BM, Zieske JD, Jung JC, et al. Molecular mechanisms controlling the fibrotic repair phenotype in cornea: implications for surgical outcomes. Invest Ophthalmol Vis Sci, 2003, 44(10):4237-4246. DOI: 10.1167/iovs.02-1188.
[18]
Kim JY, Kim MJ, Kim TI, et al. A femtosecond laser creates a stronger flap than a mechanical microkeratome. Invest Ophthalmol Vis Sci, 2006, 47(2): 599-604. DOI: 10.1167/iovs.
05
-0458.
[19]
Cankaya AB, Tekin K, Kiziltoprak H, et al. Assessment of corneal backward light scattering in the healthy cornea and factors affecting corneal transparency. Jpn J Ophthalmol, 2018,62(3): 335-341. DOI: 10.1007/s10384-018-0584-7.
[20]
Boote C, Dennis S, Newton RH, et al. Collagen fibrils appear more closely packed in the prepupillary cornea: optical and biomechanical implications．Invest Ophthalmol Vis Sci, 2003,44(7): 2941-2948.
浙公网安备 33030202001892号