Corneal Surface Elevation and Thickness in Relation to the Fit of Rigid Contact Lenses in Keratoconus and After Corneal Cross-Linking.

Purpose: To determine if factors pertaining to corneal thickness and elevation were linked to the prescribed back optic zone radius and overall diameter in keratoconus (group I), and cross-linked keratoconus (group II), cases successfully fitted with rigid contact lenses. Patients and Methods: A review of cases adapted to contact lens wear (Rose K™) and assessed using Pentacam™ (for corneal anterior surface topography, astigmatism, elevation, and topographic thickness variation) was undertaken to determine the significance of any correlation with comfort, lens usage, grading of keratoconus, corrected distance visual acuity (with glasses and contacts), refractive error, prescribed lens powers, back optic zone radius and overall diameter values were assessed. Results: Chief findings were, comfort was rated highly, lenses were worn for more than 10 hours/day in 75% of cases. RCL corrected distance logMAR acuities (median, mode, inter-quartile ranges) were 0.11, 0.12 (0.08-0.13) and 0.08, 0.08 (0.06-0.11) in groups I and II, respectively. Multiple linear regression revealed significant correlations (p<0.01) between the [A] back optic zone radius, the thinnest value of corneal thickness (x1) and anterior corneal surface elevation (x2). The respective r2 values were 0.471 in group I and 0.512 in group II. [B] overall diameter, x1 and x2. The respective r2 values were 0.282 in group I and 0.505 in group II. Conclusion: RCLs were well-tolerated in both groups. The r2 values imply there is a 50% chance of correctly predicting the suitable back optic zone radius in both groups, a 50% chance of correctly predicting the overall diameter in group II and 28% in group I cases using just x1 and x2. The thinnest value of corneal thickness and anterior corneal surface elevation could be used to quickly select the BOZR and OD during RCL fitting. This has the potential to reduce chair-time, waste and improve efficiency.

Pachymetry and Elevation Back Map Changes in Keratoconus Patients After Crosslinking Procedure.

INTRODUCTION: The crosslinking (CXL) procedure using the standard Dresden protocol is established as the gold standard for the treatment of progressive keratoconus. AIM: The aim of this paper is to correlate the pachymetry and elevation back map (EBM) changes in the period from 3 to12 months of keratoconus patients after the CXL procedure. M. METHODS: Forty-four eyes of 34 patients with keratoconus were analyzed after performed standard Dresden protocol CXL procedure. All of them underwent complete preoperative examination with a follow up of 12 months with a focus on pachymetry and EBM changes performed by Oculus Pentacam (Scheimpflug technology) analysis. RESULTS: Pachymetry changed significantly in 12 months post cross-linking, especially in the first 6 months after which it slightly increased. Differences in EBM preoperatively and 12 months postoperatively were not statistically significant. CONCLUSION: Corneal pachymetry in keratoconus patients decreases after the CXL procedure. Differences in pachymetry preoperatively and 3, 6 and 12 months postoperatively were statistically significant, but the value of corneal thickness increased from the third month to 12 months post-op. Differences in EBM preoperatively and 12 months postoperatively were not still statistically significant, which is good, because the increase in elevation, as one of the signs of progression of the keratoconus - did not occur.

Keratoconus Progression Classification One Year After Performed Crosslinking Method Based on ABCD Keratoconus Grading System.

INTRODUCTION: Keratoconus is described as a degenerative bilateral, progressive, noninflammatory corneal disorder characterized by ectasia, thinning, and increased curvature. Keratoconus progression classification 1 year after performed crosslinking method in this study is based on the ABCD keratoconus grading system. AIM: To evaluate the possible keratoconus progression one year after performed a crosslinking (CXL) method based on the ABCD keratoconus grading system. Methods: Seventeen keratoconus patients (22 eyes) were included in this prospective study. CXL procedure was performed using the standard Dresden protocol at Eye Clinic Svjetlost Sarajevo with the inclusion period from January 2017 to January 2018. Twelve patients had monocular, and 5 patients had binocular treatments with follow up of 12 months. Preoperative and postoperative stages were compared using the ABCD keratoconus grading system measured on rotating Scheimpflug corneal tomography-based machine - Pentacam (Pentacam HR, Oculus Optikgeräte GmbH, Wetzlar, Germany). RESULTS: Out of 22 eyes, one eye had keratoconus stage I-II, 6 eyes had stage II, 4 eyes had stage III, and 9 eyes had stage III-IV. There was no statistically significant gradient change of keratoconus in comparison to one month after the surgery, p>0.05. There was no progression of the gradient when comparing to the preoperative stage. CONCLUSIONS: Corneal cross-linking could effectively stabilize the progression of keratoconus, as assessed by key corneal topographic parameters. Analyzing the trend of stage change in 12 months follow up after the crosslinking procedure of keratoconus patients there was no progression of a gradient in comparison to the preoperative stage. According to our results, we can conclude that CXL is a safe and effective procedure in treating keratoconus.

Cross-linking treatment for better visual acuity.

Aim To correlate the maximum anterior sagittal curvature (Kmax) changes and uncorrected (UDVA) and corrected distance visual acuity (CDVA) in keratoconus patients after the cross-linking (CXL) procedure. Methods Forty-four eyes of 34 patients with keratoconus were analysed after the standard Dresden protocol CXL procedure had been performed. All patients underwent complete preoperative examination with a follow-up of 12 months with focus on UDVA, CDVA and Oculus Pentacam (Scheimpflug technology) analysis. We analysed and correlated Kmax changes in the postoperative period of 12 months together with visual acuity changes. Results Visual acuity improved significantly in the first 3 months after the procedure and even more significantly until the end of the first year. Even Kmax is the most relevant and most followed parameter for progression and regression of keratoconus, its lowering was not directly correlated with the visual acuity improvement (both uncorrected and corrected) in the first 6 months after corneal CXL procedure. Kmax was changed significantly in the period of 12 months post cross linking, but not in the first 6 months. Conclusion Corneal CXL should be considered as a procedure not just for corneal stiffening and stabilization, but also for visual acuity improvement in keratoconus patients.

Treatment of High Astigmatism with WaveLight Allegretto Eye-Q Excimer Laser Platform.

INTRODUCTION: The WaveLight Allegretto Eye-Q is a flying-spot excimer laser, with a pulse repetition rate of 400Hz, with two galvanometric scanners for positioning laser pulses. The system has an infrared high speed camera operating at 400Hz to track the patient's eye movements that either compensates for changes in eye position or interrupts the treatment if the eye moves outside a preset predetermined range. AIM: The purpose of this study was to investigate WaveLight Allegretto Eye-Q 400Hz laser delivery platform aimed to correct astigmatism by subjecting the pre and postoperative astigmatic values to vector analysis. METHODS: Patients were divided into two groups, depending on the type of astigmatism. Astigmatism was between 2 and 7 diopters (D). A total of 188 eyes (110 patients), 127 eyes (71 patients) with myopic astigmatism and 61 eyes (39 patients) with mixed astigmatism underwent unremarkable LASIK correction on WaveLight Allegretto Eye-Q 400Hz. The preoperative and postoperative sphere, negative cylinder [C] and axis (ø) of manifest refractions were subjected to vector analysis by calculations of the standard J0 (cos [4π(ø-90)/360]xC/2) and J45 (sin[4π(ø-90)/ 360]xC/2). RESULTS: Reporting the key results, we found that J0 significantly reduced after LASIK (p<0.001) but not J45. There was no significant association between individual pairs of pre and postoperative J0 &J45 values. CONCLUSION: WaveLight Allegretto 400Hz showed excellent results for treating patients with high astigmatism, regardless whether it is mixed or myopic astigmatism. The J45 did not reduce significantly possibly because of the low number of eyes with oblique astigmatism. There was no genuine difference postoperatively between groups treated on WaveLight Allegretto platform according to the vector analyses.

Lasik as a Solution for High Hypermetropia.

AIM: To evaluate safety and efficacy of Laser in situ Keratomileusis (LASIK) procedure for the correction of high hypermetropia. METHODS: Retrospective study of 160 patients (266 eyes) who underwent LASIK procedure for the correction of hypermetropia between +3.00 and +7.00 diopters(D) and cylinder up to 2.00D from January 2013 and August 2015. All ablations were performed with Wavelight Allegretto Eye-Q400Hzexcimer laser (Alcon, Forth Worth, TX, USA) with aberration free module and were centered on a corneal vertex. All flaps were made with Moria M2 (Moria, Antony, France) mechanical microkeratome (90µm head). Preoperative and postoperative uncorrected and corrected distant visual acuity (UDVA, CDVA), spherical equivalent (SE) and a berrometry for 5mm pupil were measured. Measurements were taken at 1 week, 1,3,6 and 12 months after the surgery. Wilcoxon Signed Ranks Test was used for statistical analysis. RESULTS: Postoperative UDVA was lower than preoperative CDVA at 1 week(p=0.001), at 1 month there was no difference (p=0.099), and at 3,6 and 12 months UDVA was better (p<0.0001). Preoperative SE was 4.69±1.20D (+3.75 to +7.50D). At 1 week SE was 0.03±0.67D (-0.50 to +0.63D), while at 1 year regressed to 0.58±0.56D (+0.25 to +0.88D). Sphere shifted from negative values targeted in treatment planning to compensate for regression to positive values. There was significant difference in SE at every time point (p<0.0005). There was a significant increase in coma (p<0.0001), trefoil (p<0.0001, p=0.0006) and spherical aberration (p=0.022, p=0.0052) at 1 week and 1 month postoperatively, without change throughout the rest of follow up. CONCLUSION: LASIK for high hypermetropia showed satisfactory results in postoperative refraction with reasonable regression without significant loss of lines of visual acuity. However, more test are necessary to asses optical quality.

Epidemiology of Diabetic Retinopathy at Eye Clinic Svjetlost Sarajevo: Two Years Retrospective Single Center Study.

INTRODUCTION: Diabetic retinopathy (DR) is an important cause of blindness, and occurs as a result of long-term accumulated damage to the small blood vessels in the retina. 2.6% of global blindness can be attributed to diabetes. Disease severity was most often classified by the Early Treatment Diabetic Retinopathy Study (ETDRS) classification for DR severity. Patients are usually categorized based on the severity of DR as having mild nonproliferative diabetic retinopathy (NPDR), moderate NPDR, severe NPDR, or proliferative diabetic retinopathy (PDR). AIM: To evaluate DR status among patients at Eye Clinic Svjetlost Sarajevo , both, type 1 and type 2 DM patients who presented in our clinic at 2 years period - from June 2016 to June 2018. This is single center study. METHODS: Retrospective analysis of 753 diabetic patients that came for the first check up in our institution during those two years, 363 patients were male and 390 were female. Patients were divided in 3 groups (based on DR changes): a) No changes, b) Nonproliferative DR (with and without Diabetic macular edema-DME), c) Prolipherative DR (with and without DME + Advanced PDR). RESULTS: There were 35% of patients with no ocular changes, 41.2% had NPDR and 24% had PDR. Prevalence of DR in our study was 65.32%. Distribution of NPDR was 66.27%, and PDR was 33.73%. DME was present in 33.70% cases. In NPDR, DME was presented in 51% of the cases, while in PDR was presented in 49% of the cases. In state of advanced PDR, PDR was presented in 30.52% cases, tractional detachment and haemophtalmus in 50.20% of cases and neovascular glaucoma in 19.28%. Sixty-three patients ended up with vitroretinal surgery (8.4%) while in other studies that number is up to 3%. Out of that number 9 patients were patient with virgin eyes (14.28%). Neovascular glaucoma occurred in 19.28% of diabetics with proliferative retinopathy and 4.60% in all of diabetics. CONCLUSION: Diabetic retinopathy status of patients presenting at Eye clinic Svjetlost Sarajevo, Bosnia and Herzegovina is quite poor. There is a big need for early DR screening measures, good prevention and management of DR risk factors. Adequate and ON TIME management of DM and its vision threatening complications is of major importance.

Refractive Outcomes of Posterior Chamber Phakic Intraocular Lens Implantation for Correction of Myopia and Myopic Astigmatism.

OBJECTIVES: The aim was to examine efficacy and safety after Implantable Collamer Lens (ICL) implantation for correction of myopia et myopic astigmatism. METHODS: This prospective clinical study included 28 eyes of 16 patients which underwent implantation of ICL for correction of myopia up to -18,00 diopters (D) and myopic astigmatism up to -6,00 D in the Eye Clinic Svjetlost Sarajevo, from January 2013 to January 2016. Uncorrected distance visual acuity (UDVA), spherical equivalent (SE), corrected distance visual acuity (CDVA), intraocular pressure (IOP), endothelial cell (EC) density were evaluated at one, six and twelve months. For statistical analysis SPSS for Windows and Microsoft Excel were used. RESULTS: Out of 16 patients, with mean age of 28,21 ± 4,06 years, 12 of them had binocular and 4 of them had monocular procedure. After 12 months mean UDVA was 0,76 ± 0,16 compared to UDVA 0,04 ± 0,03 preoperatively. Mean SE preoperatively was -0,21 ± 0,27 D compared to -9,52 ± 3,69 D preoperatively. At 12 months one eye (3,57%) lost 2 Snellen lines. In this study 8 eyes (28,57%) gained 1 line, 5 eyes gained (17,56%) 2 lines, and 3 eyes (10,72%) gained 3 lines. EC loss was 5,50±4.71% after 12 months. There was no significant change of IOP by the end of 12 months follow up period. One haptic crack was reported as the only intraoperative complication. Three postoperative complications were: two lens rotations and one retinal detachment. CONCLUSION: Implantation of ICL is an effective and safe method for reducing or correcting myopia and myopic astigmatism.

One Year Follow-Up After Veriflex Phakic Intraocular Lenses Implantation for Correction of Myopia.

OBJECTIVES: The aim of this study was to evaluate visual and refractive outcomes after Veriflex phakic intraocular lenses (pIOL) implantation in moderately myopic eyes as well as postoperative complications. METHODS: This prospective clinical study included 40 eyes of 26 patients which underwent implantation of Veriflex for correction of myopia from -6.00 to -14.50 diopters (D) in the Eye Clinic Svjetlost Sarajevo, from January 2011 to January 2014. Uncorrected distance visual acuity (UDVA), manifest residual spherical equivalent (MRSE), intraocular pressure (IOP), endothelial cell (EC) density were evaluated at one, three, six and 12 months. Other complications in postoperative period were evaluated. For statistical analysis SPSS for Windows and Microsoft Excel were used. RESULTS: Out of 26 patients 14 had binocular and 12 monocular procedure, with mean age of 29.8±6.5 years. After 12 months mean UDVA was 0.73±0.20. Mean MRSE was -0.39±0.31D and 90% of eyes had MRSE within ±1D. EC loss was 7.18±4.33%. There was no significant change of IOP by the end of 12 months follow up period. The only intraoperative complication was hyphema and occurred in one eye. Few postoperative complications were: subclinical inflammation in three eyes (7,5%), pigment dispersion in four eyes (10%), ovalisation of papilla in 2 eyes (5%) and decentration of pIOL in 2 eyes (5%). CONCLUSION: Implantation of iris-claw phakic lenses Veriflex for treating moderately high myopia is a procedure with good visual and refractive results and few postoperative complications.

Efficacy and safety of iris-supported phakic lenses (Verisyse) for treating moderately high myopia.

AIM: To evaluate efficacy and safety of iris-supported phakic lenses (Verisyse) for treating moderately high myopia. METHODS: This prospective clinical study included 40 eyes from 29 patients, who underwent implantation of Verisyse for correction of myopia from -6.00 to -14.50 diopters (D) in the Eye Clinic ''Svjetlost'', Sarajevo, from January 2011 to January 2014. Uncorrected distance visual acuity (UDVA), manifest residual spherical equivalent(MRSE), postoperative astigmatism, intraocular pressure(IOP), endothelial cell (EC) density were evaluated at one, three, six and twelve months. Corrected visual acuity (CDVA), index of safety and efficacy were evaluated after 12 months. RESULTS: Out of 29 patients 15 were males and 14 females, with mean age of 27.9 ± 5.0. After 12 months 77.5% eyes had UDVA ≥ 0.5 and 32.5% had UDVA ≥ 0.8. Mean MRSE was 0.55D ±0.57D and mean postoperative astigmatism -0.86D ± 0.47D. Efficacy index was 1.09 ± 0.19 and safety index 1.18 ± 0.21. One eye(2.5%) lost two Snellen lines and three eyes (7.5%) one line, 11 eyes (27.5%) gained one line, and five eyes (15.5%) gained two lines. EC loss after 12 months was 7.59 ± 3.05%. There was no significant change of IOP after one year follow up. CONCLUSION: Implantation of iris-supported phakic lenses (Verisyse) for treating moderately high myopia is an efficient and safe procedure.