PURPOSE: To report two cases of femtosecond laser-assisted small incision deep lamellar endothelial keratoplasty (DLEK) for patients with corneal endothelial decompensation by Fuchs dystrophy and glaucoma METHODS: Femtosecond laser (IntraLase(R); IntraLase Corp., Irvine, CA) with 15 kHz of repetition rate, was used for a 9.5 mm diameter by 400 micrometer thickness donor corneal lamellar dissection. RESULTS: In Case 1, the graft was clear and compact without interface haze, Orbscan showed smooth and regular corneal surface, specular microscopy was unremarkable without sign of corneal endothelial damage, and Optical coherence tomography showed uniform graft well attached to recipient stroma with minimal interface reflection at 2 months postoperation. In Case 2, the graft was clear and compact with minimal interface haze at 1 month postoperation. Femtosecond laser-assisted small incision DLEK was safe and technically feasible in our cases; however, further evaluation is required to determine long-term effects.
Aged ; Aged, 80 and over ; Corneal Edema/*surgery ; Corneal Surgery, Laser/*methods ; Corneal Topography ; Corneal Transplantation/*methods ; Endothelium, Corneal/*transplantation ; Female ; Fuchs' Endothelial Dystrophy/*surgery ; Humans ; Male ; Tomography, Optical Coherence ; Visual Acuity

PURPOSE: To report two cases of femtosecond laser-assisted small incision deep lamellar endothelial keratoplasty (DLEK) for patients with corneal endothelial decompensation by Fuchs dystrophy and glaucoma METHODS: Femtosecond laser (IntraLase(R); IntraLase Corp., Irvine, CA) with 15 kHz of repetition rate, was used for a 9.5 mm diameter by 400 micrometer thickness donor corneal lamellar dissection. RESULTS: In Case 1, the graft was clear and compact without interface haze, Orbscan showed smooth and regular corneal surface, specular microscopy was unremarkable without sign of corneal endothelial damage, and Optical coherence tomography showed uniform graft well attached to recipient stroma with minimal interface reflection at 2 months postoperation. In Case 2, the graft was clear and compact with minimal interface haze at 1 month postoperation. Femtosecond laser-assisted small incision DLEK was safe and technically feasible in our cases; however, further evaluation is required to determine long-term effects.
Aged ; Aged, 80 and over ; Corneal Edema/*surgery ; Corneal Surgery, Laser/*methods ; Corneal Topography ; Corneal Transplantation/*methods ; Endothelium, Corneal/*transplantation ; Female ; Fuchs' Endothelial Dystrophy/*surgery ; Humans ; Male ; Tomography, Optical Coherence ; Visual Acuity

The purpose of this study is to assess the efficacy of the multi-zone cross-cylinder method as compared with the single method for astigmatism correction using LASIK. This prospective study enrolled 40 patients (52 eyes) who underwent the cross-cylinder method using LASIK, and 52 patients (60 eyes) who underwent the single method using LASIK: all patients were given a diagnosis of complex myopic astigmatism from the department of ophthalmology of this hospital between January 2002 and July 2003. Preoperatively, the mean spherical equivalent refraction was .3.85 +/- 1.13 D in the cross-cylinder group and .4.05 +/-1.20 D in the single method group (p = 0.23). The mean cylinder was .2.05 +/-1.58 D in the cross-cylinder group and .1.95 +/-1.12 D in the single method group (p = 0.31). 6 months after treatment the results were a mean spherical equivalent refraction of .0.26 +/-0.30 D in the crosscylinder group and -0.34 +/-0.35 D in the single method group (p = 0.13). The mean cylinder was .0.38 +/-0.29 D in the cross-cylinder group and .0.45 +/-0.30 D in the single method group (p = 0.096). There were no statistically significant differences between the two groups. The mean BCVA was not different from mean preoperative BCVA in both groups (i.e., 0.98 +/-0.10, 0.96 +/-0.25, p = 0.86). Postoperatively, patient complications that included night halo, glare and corneal haze were not noted in either group. In conclusion, the results of cross-cylinder method are no different from the single method for the correction of a complex astigmatism. In the future, studies will have to be conducted to assess the efficacy of the cross-cylinder method in consideration of those factors that can affect the postoperative outcome.
Adult ; Astigmatism/*surgery ; Corneal Stroma/surgery ; Humans ; Keratomileusis, Laser In Situ/*methods ; Myopia/*surgery ; Postoperative Complications ; Prospective Studies

PURPOSE: To compare the changes in posterior corneal curvature using scanning slit topography (Orbscan II) and Scheimpflug imaging (Pentacam) before and after Epi-laser in situ keratomileusis (LASIK) for myopia. METHODS: In a prospective observational case-series study, 20 myopic patients having undergone Epi-LASIK were examined serially with two different devices, Orbscan II and Pentacam, preoperatively and one month postoperatively. Posterior central elevation (PCE) and posterior maximal elevation (PME) were compared between the two devices, and the changes in parameters after Epi-LASIK were analyzed using a difference map. RESULTS: All parameters (preoperative and postoperative PCE and preoperative and postoperative PME) that were measured using the Orbscan II were significantly greater compared to those of the Pentacam (for all p < 0.001). PCE and PME were significantly increased one month postoperatively in the Orbscan II measurements (p < 0.05) but were not significantly increased in the Pentacam measurements. Also, DeltaPCE and DeltaPME, in the difference map obtained by each serial scanning, were significantly greater in the Orbscan II measurements than with the Pentacam (p = 0.012, p = 0.016). CONCLUSIONS: The Pentacam measurements displayed significantly reduced values in all parameters related to posterior corneal elevation compared to those of the Orbscan II. The Pentacam showed no significant change in posterior corneal curvature after Epi-LASIK, based on the difference map.
Adult ; Corneal Topography/*methods ; Female ; Humans ; Keratomileusis, Laser In Situ/*methods ; Male ; Myopia/*surgery ; Prospective Studies ; Treatment Outcome

To evaluate the relationship between ablation zone demm in PRK and 88.7% were decentered less than 0.75 mm in LASIK. The most meridional displacement was toward the superonasal quadrant; 46% in PRK and 51% in LASIK. There was less decentration in males, in the 2nd-operated eye, in older age, PRK, in larger ablation diameter, and in shallower ablation depth, but these differences were not statistically significant.
Adult ; Corneal Transplantation/methods* ; Factor Analysis, Statistical ; Female ; Human ; Keratectomy, Photorefractive, Excimer Laser* ; Laser Surgery* ; Male ; Middle Age ; Myopia/surgery* ; Pupil*

PURPOSE: The corneal change induced by refractive procedures influence both the postoperative refractive status and the ocular spherical aberration (SA). We evaluated changes in corneal SA after three types of surface ablation: phototherapeutic keratectomy (PTK), myopic photorefractive keratectomy (PRK), and myopic wavefront-guided laser epithelial keratomileusis (LASEK). METHODS: Twenty-six eyes (25 patients) were subjected to PTK 26 eyes (14 patients) to PRK, and 34 eyes (17 patients) to wavefront-guided LASEK. Corneal SA was measured with the iTrace in all patients both preoperatively and 6 months postoperatively. RESULTS: Six months after surgery, mean corneal SA was -0.173 +/- 0.171 micrometer in the PTK group, 0.672 +/- 0.200 micrometer in the PRK group, and 0.143 +/- 0.136 micrometer in the wavefront-guided LASEK group. The mean difference between the preoperative and postoperative corneal SA (DeltaSA) was -0.475 micrometer in the PTK group, 0.402 micrometer in the PRK group, and -0.143 micrometer in the wavefront-guided LASEK group. CONCLUSIONS: Surgically induced changes in corneal SA vary with procedure. The prediction of the pattern of SA change induced by various surface ablation procedures may be helpful for developing future surgical procedures.
Adult ; Aged ; Corneal Dystrophies, Hereditary/*surgery ; Corneal Wavefront Aberration/*surgery ; Female ; Follow-Up Studies ; Humans ; Keratomileusis, Laser In Situ/*methods ; Male ; Middle Aged ; Myopia/*surgery ; Photorefractive Keratectomy/*methods ; Prospective Studies ; Treatment Outcome

PURPOSE: The corneal change induced by refractive procedures influence both the postoperative refractive status and the ocular spherical aberration (SA). We evaluated changes in corneal SA after three types of surface ablation: phototherapeutic keratectomy (PTK), myopic photorefractive keratectomy (PRK), and myopic wavefront-guided laser epithelial keratomileusis (LASEK). METHODS: Twenty-six eyes (25 patients) were subjected to PTK 26 eyes (14 patients) to PRK, and 34 eyes (17 patients) to wavefront-guided LASEK. Corneal SA was measured with the iTrace in all patients both preoperatively and 6 months postoperatively. RESULTS: Six months after surgery, mean corneal SA was -0.173 +/- 0.171 micrometer in the PTK group, 0.672 +/- 0.200 micrometer in the PRK group, and 0.143 +/- 0.136 micrometer in the wavefront-guided LASEK group. The mean difference between the preoperative and postoperative corneal SA (DeltaSA) was -0.475 micrometer in the PTK group, 0.402 micrometer in the PRK group, and -0.143 micrometer in the wavefront-guided LASEK group. CONCLUSIONS: Surgically induced changes in corneal SA vary with procedure. The prediction of the pattern of SA change induced by various surface ablation procedures may be helpful for developing future surgical procedures.
Adult ; Aged ; Corneal Dystrophies, Hereditary/*surgery ; Corneal Wavefront Aberration/*surgery ; Female ; Follow-Up Studies ; Humans ; Keratomileusis, Laser In Situ/*methods ; Male ; Middle Aged ; Myopia/*surgery ; Photorefractive Keratectomy/*methods ; Prospective Studies ; Treatment Outcome

PURPOSE: To compare corneal flaps created in rabbits with a 60 kHz femtosecond (FS) laser using different levels of raster energy and to measure early inflammation, corneal stromal cell death, and late postoperative adhesion strength. METHODS: Sixty rabbits were divided into three groups of 20 each. A flap 110 micrometer thick and 9.0 mm in diameter was made in one eye of each rabbit at raster energies of 0.7 microJ, 1.1 microJ, and 2.4 microJ. Histopathological evaluation for inflammation and apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed at 4 and 24 hours after flap creation. The adhesion strength of the flaps was measured with a tension meter at 1 and 3 months. RESULTS: Twenty four hours after flap creation, the 2.4 microJ group had more inflammatory and CD11b-positive cells than the 0.7 and 1.1 microJ groups. The number of TUNEL-positive cells increased with raster energy at 4 and 24 hours. The grams of force (gf) needed to detach the flaps at 3 months was significantly higher in 2.4 microJ group (170 gf) than in 0.7 microJ group (97.5 gf) and 1.1 microJ group (100 gf, p = 0.03). CONCLUSIONS: Using raster energy lower than 1.1 microJ to make a flap with a 60 kHz FS laser decreases inflammatory cell infiltration and corneal stromal cell death in the central cornea but may result in a weaker flap than using higher raster energy (2.4 microJ).
Animals ; Cell Death ; Corneal Stroma/*pathology/*surgery ; Keratitis/*pathology/*prevention & control ; Laser Therapy/*methods ; Male ; Models, Animal ; Rabbits ; *Surgical Flaps ; Tissue Adhesions/pathology/surgery

PURPOSE: To compare corneal flaps created in rabbits with a 60 kHz femtosecond (FS) laser using different levels of raster energy and to measure early inflammation, corneal stromal cell death, and late postoperative adhesion strength. METHODS: Sixty rabbits were divided into three groups of 20 each. A flap 110 micrometer thick and 9.0 mm in diameter was made in one eye of each rabbit at raster energies of 0.7 microJ, 1.1 microJ, and 2.4 microJ. Histopathological evaluation for inflammation and apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed at 4 and 24 hours after flap creation. The adhesion strength of the flaps was measured with a tension meter at 1 and 3 months. RESULTS: Twenty four hours after flap creation, the 2.4 microJ group had more inflammatory and CD11b-positive cells than the 0.7 and 1.1 microJ groups. The number of TUNEL-positive cells increased with raster energy at 4 and 24 hours. The grams of force (gf) needed to detach the flaps at 3 months was significantly higher in 2.4 microJ group (170 gf) than in 0.7 microJ group (97.5 gf) and 1.1 microJ group (100 gf, p = 0.03). CONCLUSIONS: Using raster energy lower than 1.1 microJ to make a flap with a 60 kHz FS laser decreases inflammatory cell infiltration and corneal stromal cell death in the central cornea but may result in a weaker flap than using higher raster energy (2.4 microJ).
Animals ; Cell Death ; Corneal Stroma/*pathology/*surgery ; Keratitis/*pathology/*prevention & control ; Laser Therapy/*methods ; Male ; Models, Animal ; Rabbits ; *Surgical Flaps ; Tissue Adhesions/pathology/surgery

OBJECTIVETo observe the influence of flap-on or flap-off Epipolis laser in situ keratomileusis (epi-LASIK) on the release of transforming growth factor-β1 (TGF-β1) in tear fluid and corneal haze formation.

METHODSThirty patients (60 eyes) with myopia underwent epi-LASIK surgery with epithelial flap repositioning (flap-on) in the right eyes and epithelial flap removal (flap-off) in the left eyes. The level of TGF-β1 in tears was measured preoperatively and on days 1, 3, and 7 postoperatively. Corneal haze was graded at 1, 3 and 6 months after surgery.

RESULTSThe mean preoperative spherical equivalent refraction was -4.98∓2.28 D (-2.50 to -7.25 D) in flap-on group and -5.20∓4.02 D (-1.75 to -7.00 D) in flap-off group, showing no significant difference between the two groups (P=0.80). TGF-β1 levels in the tear fluid were similar in the two groups preoperatively (P=0.11) and at 1, 3, and 7 days postoperatively (P=0.55, 0.45, 0.19, respectively). TGF-β1 levels in tears gradually decreased after the first postoperative day in both groups, but were still higher than the preoperative value till the 7th postoperative day. Corneal haze scores in the two groups were similar at 1 month (P=0.98), 3 months (P=0.52), and 6 months (P=0.72) after the operation.

CONCLUSIONFlap-on and flap-off epi-LASIK surgeries do not differ significantly in postoperative TGF-β1 levels in the tear fluid or in the postoperative haze scores. TGF-β1 may play a role in corneal wound healing.

Adult ; Cornea ; surgery ; Epithelium, Corneal ; pathology ; surgery ; Female ; Humans ; Keratomileusis, Laser In Situ ; methods ; Male ; Postoperative Period ; Surgical Flaps ; Tears ; metabolism ; Transforming Growth Factor beta1 ; metabolism ; Young Adult