Assessment of Corneal Densitometry in Big-Bubble Dissection Versus Manual Dissection Deep Anterior Lamellar Keratoplasty.

PURPOSE: The aim of this study was to assess corneal densitometry and visual outcomes after big-bubble deep anterior lamellar keratoplasty (BB-DALK) and manual dissection deep anterior lamellar keratoplasty in patients with keratoconus. METHODS: This retrospective comparative observational study included 40 keratoconic patients who underwent DALK surgery: 22 eyes had BB-DALK (group I) and 18 eyes had failed BB technique and DALK was completed by manual dissection (group II). Best -corrected visual acuity (BCVA), corneal topographic parameters, residual stromal tissue thickness, and endothelial cell count were recorded at 1, 3, 6, and 12 months postoperatively. Densitometric analysis of different corneal layers and zones was performed using Scheimpflug tomography at each visit; values were recorded and compared between the 2 groups. RESULTS: At 1 and 6 months postoperatively, BCVA was better in group I than in group II, but with no statistically significant difference. At 12 months, the visual acuities became nearly similar in both groups (0.30 ± 0.13 vs. 0.30 ± 0.14 logarithm of the minimum angle of resolution, P = 0.888). Regarding corneal densitometric analysis, the recorded values for the posterior corneal layer were significantly higher in group II compared with group I at 3, 6, 9, and 12 months postoperatively in the 0- to 2-mm zone (P < 0.001) and the 2- to 6-mm zone (P = 0.029, 0.028, 0.001, and <0.001). CONCLUSIONS: Manual dissection DALK after failed BB technique may affect the interface stromal reflectivity up to 12 months postoperatively. However, this does not significantly affect the visual acuity in comparison with successful BB-DALK.

Secondary piggyback implantation versus IOL exchange for symptomatic pseudophakic residual ametropia.

BACKGROUND: To evaluate the safety and efficacy of implanting a secondary IOL in comparison with IOL exchange to correct residual spherical refractive error after cataract surgery. METHOD: This prospective case series included 23 pseudophakic eyes of 23 patients. They were divided into two groups: group I included 12 eyes for whom secondary piggyback IOL implantation in the ciliary sulcus was done, and group II included 11 eyes for whom IOL exchange was done. The mean follow up was 18 ± 4.2 months and 20 ± 3.6 months in groups I and II respectively. The visual and refractive outcomes were evaluated, and any intraoperative or postoperative complications was recorded. RESULTS: The mean spherical equivalent in group I (secondary piggyback implantation), was reduced from -6.2 ± 2.2 diopters preoperatively to -0.28 ± 0.59D postoperatively in myopic eyes and from 4.79 ± 1.02D to 0.03 ± 0.74D in hyperopic eyes. Ninety-two percent of eyes were within ±0.5D of intended correction. In group II (IOL exchange), the mean SE was reduced from -5.88 ± 3.1D preoperatively to 0.16 ± 1.09 D postoperatively in myopic eyes and from 5.05 ± 0.93D preoperatively to 0.11 ± 0.69D postoperatively in hyperopic eyes. Eighty-two percent of eyes had postoperative SE within ± 0.5D of the intended correction. UCVA improved significantly in both groups. Rupture of the posterior capsule occurred in one eye in group II. Only one eye in group II lost one line of BCVA. CONCLUSION: Secondary piggyback implantation in the ciliary sulcus is an effective, safe, and easy treatment for a pseudophakic ametropia.

Homocysteine and hydroxyproline levels in patients with primary open-angle glaucoma.

AIM: To assess the levels of homocysteine (Hcy) and hydroxyproline (Hyp) in aqueous humor and plasma of human eyes with primary open-angle glaucoma (POAG) and to correlate their concentrations with the severity of glaucoma. METHODS: Fifty patients with POAG and 35 patients with senile cataract (control group) were enrolled in the study prospectively. Aqueous humor samples were obtained by paracentesis from glaucoma and cataract patients who were undergoing elective surgery. Aqueous humor and corresponding plasma samples were analyzed for Hcy and Hyp concentrations by high-performance liquid chromatography and spectrometry, respectively. RESULTS: Hcy and Hyp levels were significantly higher in aqueous humor of POAG patients with respect to the comparative group of cataract patients (p < 0.001). No significant difference in the levels of Hcy and Hyp in plasma of POAG and cataract patients. A positive correlation was found between Hcy and Hyp in aqueous humor of POAG patients (p < 0.001). No significant correlation was found between either Hcy or Hyp levels and the severity of visual field loss. CONCLUSION: Increased levels of aqueous humor Hcy and Hyp may be associated with POAG. In addition, Hcy and Hyp may be useful protein levels in aqueous humor of POAG patients as a consequence of glaucomatous damage.

Wavefront-optimized ablation versus topography-guided customized ablation in myopic LASIK: comparative study of higher order aberrations.

BACKGROUND AND OBJECTIVE: To compare the outcomes of wavefront-optimized ablation and topography-guided ablation in fellow eyes of patients undergoing laser in situ keratomileusis (LASIK) for myopia. PATIENTS AND METHODS: This prospective study included 84 patients who underwent LASIK in both eyes: wavefront-optimized ablation in one eye (group I) and topography-guided ablation in the fellow eye (group II). The Moria2 microkeratome with a 110 single-use head (Moria, Antony, France) was used to create a superior hinged flap and the Allegretto Wave Excimer Laser (Alcon/Wavelight Light Laser Technologie GmbH, Erlangen, Germany) for photoablation. The Allegretto wave analyzer was used to measure the ocular aberrations before and 6 months after LASIK. Refractive visual outcomes and ocular aberration changes were compared between the two treatment modalities. RESULTS: Six months postoperatively, the mean uncorrected visual acuity of group II was statistically better than that of group I (P = .02). Seventy percent of group I and 83% of group II achieved a postoperative spherical equivalent refraction of ±0.5 diopters. The postoperative total root-mean-square of higher order aberrations (HOAs) of group II was smaller than that of group I, but the difference was not statistically significant (P = .51). There was a decrease in most of the individual terms of HOAs in group II, but it was only statistically significant in Z(3) (-1) (P = .04). The reverse occurred in group I, where most of the individual terms of HOAs increased, but it was not statistically significant. Significant improvement was only noted in Z(5) (3) (P = .05) and Z(5) (5) (P = .04). CONCLUSION: Both wavefront-optimized ablation and topography-guided ablation provided good refractive results, but the latter induced fewer HOAs.

Evaluation of the role of timolol 0.1% gel in myopic regression after laser in situ keratomileusis.

PURPOSE: To evaluate the efficacy of the concomitant administration of antiglaucoma medications namely timolol 0.1% gel in cases with myopic regression after myopic laser in situ keratomileusis (LASIK). DESIGN: Prospective observational clinical trial. SUBJECTS AND METHODS: Ninty five eyes of 75 patients were included in this study prospectively. The mean myopic regression was -1.29 ± 0.83 diopters (range -0.5 to -4.62) after myopic LASIK. The eyes were divided into two groups: 50 eyes administrated timolol 0.1% gel once daily for 12 months (treated group), and 45 eyes were age matched (control group). We assessed the amounts of myopic regression in terms of changes in the refraction (spherical equivalent and astigmatism), intraocular pressure (IOP), pachymetry and the refractive power of the cornea measurements for all participants. RESULTS: The refractive error and visual acuity were similar between the two groups at baseline. The treated group had an improvement in spherical equivalent significantly from -1.29 ± 0.83 to -0.94 ± 1.07 diopters (P = 0.012). Astigmatism was changed from -0.94 ± 0.53 to -0.86 ± 0.60 diopters but this change was not statistically significant (P = 0.20). The IOP was decreased significantly from 12.6 ± 1.9 to 9.0 ± 1.1 mm Hg (P < 0.001). Central corneal thickness was changed from 425.6 ± 19.86 to 429 ± 18.1 µm but not statistically significant (P = 0.56). The central corneal power decreased significantly from 37.2 ± 1.8 to 36.4 ± 1.3 diopters (P < 0.05). CONCLUSION: Timolol 0.1% gel was effective for reduction and improvement of myopic regression especially the spherical errors after myopic LASIK.