Mean BSCVA Research Articles

Corneal aberrations, densitometry on scheimpflug imaging, and visual acuity after deep anterior lamellar keratoplasty.

To evaluate visual acuity, corneal aberrations, and densitometry post deep anterior lamellar keratoplasty (DALK). Twenty-five eyes of 25 patients who underwent DALK for corneal stromal diseases with normal endothelium were enrolled in a prospective interventional study. Evaluation for corneal aberrations and densitometry postoperatively was performed using Scheimpflug imaging at 6 months. Anterior Segment Optical Coherence Tomography (ASOCT) was done for host-graft morphology. Correlation analysis of postoperative best-corrected visual acuity with corneal aberrations and corneal densitometry (CD) was performed. Big bubble deep anterior lamellar keratoplasty (BB-DALK) was successful in 18 patients, while 7 eyes underwent manual dissection due to failed BB (Big Bubble) technique. The mean BSCVA was 1.35 ± 0.46 logMAR units pre-operatively which improved to 0.36 ± 0.19 logMAR units post DALK at 6 months (P < 0.001). The mean Root Mean Square (RMS) (μm) of the magnitude of total corneal aberrations, HOA and LOA from central 6mm zone of cornea were 14.6 ± 9.2, 4.7 ± 2.9, and 13.8 ± 8.8, respectively. The mean anterior (120μm), central and posterior corneal (60μm) densitometry in 0-2mm zone were 25.8 ± 7.7 GSU, 18.7 ± 4.16 GSU and 10.09 ± 3.9 GSU respectively. A statistically significant correlation of postoperative residual stromal bed thickness, total corneal HOA, LOA, total corneal aberrations, HOA front and posterior corneal densitometry (0-2mm zone) with postoperative BSCVA was found. Though there is a significant improvement in BSCVA after DALK, the quality of vision in terms of aberrometry and densitometry is suboptimal, especially in cases undergoing manual DALK compared to those undergoing big bubble formation.

The First 100 Eyes of Standardized Descemet Stripping Automated Endothelial Keratoplasty versus Standardized Descemet Membrane Endothelial Keratoplasty

To compare results of the first 100 eyes of Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) that were performed with a standardized technique at a single institution. Single-center, retrospective case series. The first 100 eyes of standardized DSAEK and DMEK that underwent surgery for Fuchs corneal dystrophy at our center. We excluded patients with prior ocular surgery other than cataract surgery to limit confounding variables. Best spectacle-corrected visual acuity (BSCVA; in logarithm of the minimal angle of resolution [logMAR] units) was obtained and specular microscopy of donor corneal tissue was performed before surgery. Postoperative complications, BSCVA, and the percent of endothelial cell loss (ECL) recorded at 6 months were compared with the Student t test. Patients with pre-existing ocular comorbidity that impacted visual potential such as macular degeneration, amblyopia, advanced glaucoma, and other optic neuropathies were excluded from the analysis of visual acuity, but were included for the outcomes of complications and ECL. Visual acuity improvement, ECL 6 months after surgery, postoperative complications, iatrogenic primary graft failure (IPGF), and rebubbling. Of the 200 eyes, 62 DSAEK eyes and 70 DMEK eyes had 6-month BSCVA available and no vision-limiting comorbidities. Mean BSCVA increased from 0.41±0.19 logMAR and 0.27±0.11 logMAR before surgery to 0.20±0.13 logMAR and 0.11±0.13 logMAR 6 months after DSAEK and DMEK, respectively (P<0.001). Seventy-one DSAEK eyes and 70 DMEK eyes had 6-month ECL data available: ECL was 25.9±14.0% after DSAEK and 27.9±16.0% after DMEK (P=0.38). There were no IPGFs in the DSAEK cohort and there were 4 of 100 IPGFs after DMEK (P=0.12). Rebubbling was performed in 2 of 100 eyes after DSAEK and in 6 of 100 eyes after DMEK (P=0.28). Compared with DSAEK, DMEK provided better visual recovery and comparable 6-month ECL. The DMEK group had a higher, although not statistically significant, percentage of rebubbling procedures and IPGFs.

Mini-scleral lenses in the visual rehabilitation of patients after penetrating keratoplasty and deep lamellar anterior keratoplasty.

To evaluate fitting feasibility, efficacy, and safety of mini scleral contact lenses in correcting post corneal graft vision. Prospective interventional case series, 56 visually unsatisfied post corneal graft eyes of 45 patients were fitted with miniscleral lenses (15.8 mm). Keratometric values, UCVA and BSCVA, fit, best corrected vision with the lens, decision to order lens, comfortable daily wearing time (CDWT), contact lens handling issues, and contact lens related complications were documented. The mean age was 34.6 years (SD: 10.9), ranging from 8 to 63 years. Forty-three eyes had history of full thickness corneal graft, 12 eyes had deep anterior lamellar graft (DALK) and 1 eye had the rotational graft. The mean UCVA was 1.05 logMar (SD: 0.54), ranging from 0.30 to 2.52 logMar. The mean BSCVA was 0.73 logMar (SD: 0.50) ranging from 0.09 to 2.00 which improved to 0.17 logMar (SD: 0.19) with the miniscleral lens. All eyes had ideal (40 eyes) or acceptable (16 eyes) fits. Nineteen patients (23 eyes) ordered their lenses of whom 11 (14 eyes) continued using the lens with a mean follow up time of 21.92 months (SD: 6.8). These patients reported a mean CDWT of 9.62 h/day (SD: 4.5). Five eyes of 4 patients discontinued the lens. Four eyes were lost to follow-up. The main reported barriers for ordering the lenses were economic and handling concerns. Miniscleral contact lenses can be considered helpful in the visual management of post corneal graft patients. Other factors may influence the acceptance of the lenses.

Femtosecond laser and microkeratome preparation of ultrathin (UT) DSAEK Grafts, the six months clinical results

AbstractPurpose To evaluate the use of a femtosecond laser and a mechanical microkeratome to prepare ultrathin posterior corneal disks for Descemet stripping automated endothelial keratoplasty (DSAEK) and to assess associated visual results, disk thickness and endothelial cell loss.Methods This clinical study involved ultrathin DSAEK tissue preparation used in 28 patients with endothelial dysfunction. The first cut was performed with an Intralase FS60 laser and the second cut with a Moria CBm 300‐ microkeratome. The thickness of the first cut was modified for each cornea to obtain a final graft thickness of 120 µm. Post‐op central graft thickness was performed with corneal laser tomography (Spectralis). Central endothelial cell density (ECD) was calculated before, 3 and 6 months after surgery.Results Final graft thickness was 92.9+28.5 µm, 83.1+23.6 µm, 77.2+16.9 µm and 74.3+27.5 µm at one week, one three and six months post‐op, respectively. No loss of corneas due to irregular cuts or perforation during preparation. The mean BSCVA was 0.4, 0.5, 0.7 and 0.7(0.39, 0.35, 0.16 and 0.17 LogMAR) after one week, one, three and six months post‐op, respectively. A 26.3% and 31.2% endothelial cell loss was observed after 3 and 6 months of the surgery, respectively. Significant positive correlation between BCVA (logMAR) and central graft thickness at 1 and 3 months was observed (r=0.76,p=0.01; r=0.73,p=0.01) as well as between BCVA (logMAR) at 3 months and preoperative central graft thickness (r=0.82,p=0.007; Spearman correlation). Patients without bullous keratopathy achieved better visual outcome at 3 months (p=0.04, Mann‐Whitney test).Conclusion Femtosecond laser and microkeratome can be used sequentially to prepare custom ultrathin DSAEK grafts with no loss of corneas. This procedure minimizes the variability inherent to microkeratomes and allows very quick recovery of visual acuity after posterior lamellar keratoplasty.

Femtosecond laser and microkeratome preparation of ultrathin (UT) DSAEK grafts

AbstractAn important limitation of DSAEK is that some eyes do not achieve good visual acuity despite a clear cornea and minimal residual astigmatism. The thickness of the stromal lamella may influence the final visual acuity and better results may be achieved with thinner grafts. We describe a new technique that combines a femtosecond laser with a microkeratome to obtain consistently thin grafts, with no loss of corneas. This clinical study involves ultrathin DSAEK tissue preparation used in 28 patients with endothelial dysfunction. The first cut was performed with an Intralase FS60 laser and the second cut with a Moria CBm 300‐µm microkeratome. The thickness of the first cut was modified for each cornea to obtain a final graft thickness of 120 µm. Post‐op central graft thickness was performed with corneal laser tomography (Spectralis). Associated visual results, disk thickness and endothelial cell loss before and after surgery were evaluated. Final graft thickness was 88.3+27.6 µm, 77.2+26.6 µm and 74.3+27.5 µm at one week, one and three months post‐op, respectively. No loss of corneas due to irregular cuts or perforation during preparation. The mean BSCVA was 0.41, 0.52, and 0.72(0.39, 0.28 and 0.14 LogMAR) after one week, one and three months post‐op, respectively. Precut and post‐op (3 months) ECDs averaged 2553 cells/mm2 and 1882 cells/mm2, respectively, representing 26.3% endothelial cell loss after 3 months of the surgery. Femtosecond laser and microkeratome can be used sequentially to prepare custom ultrathin DSAEK grafts with no loss of corneas. This procedure minimizes the variability inherent to microkeratomes and allows very quick recovery of visual acuity after posterior lamellar keratoplasty.

Topical Steroids in Bacterial Keratitis, A Retrospective Cohort Study.

Purpose: To review the outcomes, risk factors and morbidity of bacterial keratitis treated with and without topical steroids. Design and Methods: Retrospective cohort study. Demographics, risk factors, culture results, ulcer characteristics, time to epithelialization, visual-acuity and recurrences were recorded. Patients were classified into 2 groups: 1.Topical antibiotics/steroids (ASG), 2.Antibiotics only group (AOG). Results: Seventy two eyes were identified; 37 were classified in the ASG and 35 in the AOG. Predisposing factors were identified in 87.5% of cases, Penetrating keratoplasty, previous surgery, contact-lens wear and Herpes-simplex keratitides were the most common overall; Microorganisms were indentified in 85.5% and 60% of ASG and AOG respectively. Epithelialization was completed at a mean 17.62 and 16.06 days in ASG and AOG respectively (p= 0.533); Final mean BSCVA was 1.59±1.07 and 1.64±1.21 logMAR in ASG and AOG respectively (p= 0.864). The number of gained Snellen lines was 0.13±0.22 in ASG and 0.14±.0.24 in AOG (p= 0.860). There were no recurrences. Conclusion: Although a non statistical significant delay in re-epithelialization was noted in the ASG, this did not translate into a statistical difference in final BSCVA, gained Snellen lines or recurrence of infection. In our series, adjuvant topical steroids were not associated with an increase in unfavorable outcomes.

Biosynthetic corneas ‐ 2 year post human implantation

Abstract Purpose To evaluate biosynthetic corneas as substitutes for donor corneas in humans followed for 2 years. Methods Recombinant human collagen type III was cross‐linked to fabricate corneal substitutes. Following proper study approval, a Phase I study was initiated. 10 patients , scheduled for corneal grafting, were enrolled. Nine had keratoconus and one a deep scar following Pseudomonas keratitis. Lamellar surgery was performed. Six overlying sutures were used to anchor the graft. Topical dexametasone and chloramphenicol was given postoperatively. The sutures were removed after 6 weeks. The patients were followed clinically and evaluated for UCVA, BSCVA and BCLVA. Sensitivity (Cochet‐Bonnet) and Shirmer were tested. Photography, OCT (Visante), topography and IVCM was documented. Results After 3 months all patients had epithelialized and implants were anchored by keratocyte ingrowth. The nerve regeneration after 24 months was lower than normal controls but better than after PKP. The mean BSCVA at 24 months was less than after PKP but BCLCVA came up to par with PKP BSCVA.The corneal thickness was stable between 3 and 24 months at about 400 µm. The Shirmer values were 20 ± 10 mm in operated eyes and 17 ± 8 mm in fellow eyes. At 18 months the sensitivity was 37 mm in operated eyes and 60 mm in fellow eyes. Conclusion Bioengineered corneal substitutes are compatible and promote regeneration of corneal cells. They show stability after 2‐3 months. The results after 2 years will be presented.

Comparison of Sequential vs Same-Day Simultaneous Collagen Cross-Linking and Topography-Guided PRK for Treatment of Keratoconus

The safety and efficacy of corneal collagen cross-linking (CXL) and topography-guided photorefractive keratectomy (PRK) using a different sequence and timing were evaluated in consecutive keratoconus cases. This study included a total of 325 eyes with keratoconus. Eyes were divided into two groups. The first group (n=127 eyes) underwent CXL with subsequent topography-guided PRK performed 6 months later (sequential group) and the second group (n=198 eyes) underwent CXL and PRK in a combined procedure on the same day (simultaneous group). Statistical differences were examined for pre- to postoperative changes in uncorrected (UCVA, logMAR) and best-spectacle-corrected visual acuity (BSCVA, logMAR), manifest refraction spherical equivalent (MRSE), keratometry (K), topography, central corneal thickness, endothelial cell count, corneal haze, and ectatic progression. Mean follow-up was 36+/-18 months (range: 24 to 68 months). At last follow-up in the sequential group, the mean UCVA improved from 0.9+/-0.3 logMAR to 0.49+/-0.25 logMAR, and mean BSCVA from 0.41+/-0.25 logMAR to 0.16+/-0.22 logMAR. Mean reduction in spherical equivalent refraction was 2.50+/-1.20 diopters (D), mean haze score was 1.2+/-0.5, and mean reduction in K was 2.75+/-1.30 D. In the simultaneous group, mean UCVA improved from 0.96+/-0.2 logMAR to 0.3+/-0.2 logMAR, and mean BSCVA from 0.39+/-0.3 logMAR to 0.11+/-0.16 logMAR. Mean reduction in spherical equivalent refraction was 3.20+/-1.40 D, mean haze score was 0.5+/-0.3, and mean reduction in K was 3.50+/-1.3 D. Endothelial cell count preoperatively and at last follow-up was unchanged (P<.05) in both groups. Statistically, the simultaneous group did better (P<.05) in all fields evaluated, with improvement in UCVA and BSCVA, a greater mean reduction in spherical equivalent refraction and keratometry, and less corneal haze. Same-day simultaneous topography-guided PRK and CXL appears to be superior to sequential CXL with later PRK in the visual rehabilitation of progressing keratoconus.

Biosynthetic corneas – evaluation in humans

AbstractCollagen‐based biosynthetic corneas, designed to mimic the extracellular matrix of the corneal stroma have been developed and extensively evaluated in animal models over the last 7 years. Human recombinant collagen type III (RHC III) was crosslinked with water‐soluble carbodiimides and fabricated into optically transparent corneal substitutes for transplantation. Following study approval of the Medical Product Agency, Sweden and the Human Ethics Committee, University of Linköping, Sweden, a Phase I study was initiated. 10 patients who were scheduled for corneal grafting were enrolled into the study. Nine had keratoconus and one had a deep scar following Pseudomonas keratitis. A central 6 mm diameter deep lamellar button was excised and was replaced by a 6.25 mm diameter 500 µm thick construct. Six overlying sutures were used to anchor the graft. Topical 0.1% dexametasone and chloramphenicol was used for the first 1 month postoperatively. The sutures were removed after 5‐7 weeks. The patients were followed clinically and evaluated for UCVA, BSCVA and VA with contact lenses. Corneal touch sensitivity (Cochet‐Bonnet) and tear production (Schirmer ) were tested. Photography, OCT (Visante), topography (Orbscan II) and in vivo confocal microscopy (Heidelberg) was documented. After 3 months all patients had stably epithelialized and implants were anchored by recipient keratocyte ingrowth. The mean BSCVA at 6 months (20/133) improved slightly at 12 months (20/90). The mean BCLCVA was 20/50 at 12 months and was notably better in younger patients (mean of 20/40 in the 5 youngest). One patient had BCLVA of 20/20 at 12 months. The mean central corneal thickness was stable between 3 and 12 months at about 400µm.The mean 5min Schirmer values were 20 ± 10mm in operated eyes and 17 ± 8 mm in fellow eyes. At 12 months the mean touch sensitivity was 25mm in operated eyes and 60mm in fellow eyes, which was the same as in penetrating grafts. In‐vivo confocal microscopy revealed the ingrowth of corneal nerves at the subbasal epithelium. We have shown for the first time that bioengineered collagen‐based corneal substitutes are fully compatible and promote regeneration of corneal cells. The 18 months follow‐up results will be presented aswell.

Outcomes of ZB5M Angle-supported Anterior Chamber Phakic Intraocular Lenses at 12 Years

To evaluate the visual and refractive stability and the potential long-term risks associated with ZB5M phakic intraocular lens (PIOL) implantation. A retrospective, non-randomized, cumulative clinical study was performed over 12 years in a consecutive group of 225 eyes implanted with the ZB5M PIOL. The main analyzed variables were visual and refractive outcomes (best spectacle-corrected visual acuity [BSCVA], uncorrected visual acuity [UCVA], and spherical equivalent), endothelial cell density, and postoperative complications. Mean preoperative spherical equivalent refraction was -17.23 +/- 7.69 diopters (D) and 12 years postoperatively it was -1.80 +/- 0.80 D. Mean BSCVA at 1- and 12-year follow-up was 0.38 +/- 0.19 and 0.57 +/- 0.18, respectively (Wilcoxon test, P < .001). At 12 years postoperatively, 3.5% of eyes lost > or = 2 lines of BSCVA. An initial 10.6% reduction in endothelial cell density was noted in the first year, followed by a mean annual rate of decrease of 1.78%. The cumulative incidence of pupil ovalization was 34.7% (78 eyes), and there was no statistical correlation with endothelial cell impairment. Bilateral hypertensive uveitis was diagnosed in 3 (1.33%) eyes. The ZB5M PIOL offers good refractive outcomes and stability in the long-term; however, endothelial cell loss increases over 12 years, requiring annual endothelial cell counts.

Refractive outcomes after arcuate keratotomy using the Terry astigmatome

Purpose: To investigate the refractive outcomes after arcuate keratotomy for astigmatism. Setting: Uludag University, Faculty of Medicine, Department of Ophthalmology, Bursa, Turkey. Method: Sixteen eyes of 11 patients with astigmatism had arcuate keratotomy using the Terry astigmatome. The mean age of the patients was 36 years ± 10 (SD). All patients received preoperative and postoperative ophthalmic examinations consisting of best spectacle-corrected (BSCVA) and uncorrected (UCVA) visual acuities, corneal topography, and ultrasonic pachymetry. Surgery was performed using topical anesthesia of oxybuprocaine 0.1% eyedrops. The Terry astigmatome was selected by the mean paracentral (estimated incision area) corneal thickness. All patients received topical ofloxacin 0.3% and topical diclofenac 0.1% eyedrops postoperatively. Results: The mean corneal astigmatism was −4.0 ± 1.1 diopters (D) (range −2.2 to −6.0 D) preoperatively and –1.8 ± 0.8 D (range −0.6 to −3.0 D) postoperatively. The mean surgically induced corneal astigmatism was 2.5 ± 0.6 D. The mean UCVA (logMAR) was 0.74 ± 0.25 preoperatively and 0.18 ± 0.23 1 week postoperatively, and the mean BSCVA (logMAR) was 0.19 ± 0.24 and 0.19 ± 0.23, respectively. There were no intraoperative or postoperative complications. Conclusion: Arcuate keratotomy using the Terry astigmatome was a safe and reliable treatment for corneal astigmatism.

Estudo das modificações oculares induzidas pelo implante estromal do anel de Ferrara em portadores de ceratocone

OBJETIVO: Comparar a acuidade visual com e sem correção, ceratometria média e equivalente esférico antes e após o implante do anel intraestromal de Ferrara em pacientes portadores de ceratocone intolerantes a lentes de contato. MÉTODOS: Foram analisados os primeiros 400 olhos com ceratocone tratados com o implante do anel de Ferrara, levando-se em consideração as alterações obtidas na curvatura corneana, acuidade visual e refração, bem como a estabilidade dos resultados no primeiro ano. RESULTADOS: Nos 400 olhos estudados, observamos redução média na curvatura corneana de 4,18 D, o equivalente esférico diminuiu 4,65 D quando comparamos os valores obtidos no pré-operatório e os do último exame realizado. A AV média não corrigida foi a que sofreu maior alteração, passando de <20/400 para 20/100 e a acuidade visual média corrigida foi de 20/100 para 20/50. Os ceratocones classificados como grau III obtiveram maior benefício com a cirurgia no que se refere à redução da curvatura corneana. O anel de Ferrara mostrou ter a propriedade de manter a curvatura corneana estável durante o período estudado, para todos os grupos. CONCLUSÃO: O anel de Ferrara mostrou produzir redução do equivalente esférico, regularização da córnea e conseqüente correção do astigmatismo irregular com desaparecimento do padrão de ceratocone, além de uma melhora significativa na acuidade visual corrigida e sem correção.

Six-year experience with excimer laser surgery for primary keratoconus in Russia.

To report our results using PRK combined with PTK to treat keratoconus. Forty-one patients (70 eyes) underwent PRK+PTK with a Nidek EC-5000 excimer laser. PRK included spherical or cylindrical ablations, or both. PRK ablation zone diameter was 6.00 mm. PTK was performed with an ablation zone diameter of 8.00 mm and a transition zone of 9 mm. PTK ablation zone was decentered toward the cone apex, according to corneal topography. Refractive results: UCVA increased from 0.07 +/- 0.003 to 0.76 +/- 0.03 (69.2% of eyes had uncorrected visual acuity of 1.0); mean BSCVA increased from 0.70 +/- 0.03 to 0.83 +/- 0.04; myopia decreased from a mean 5.32 +/- 0.62 D to 1.55 +/- 0.30 D and astigmatism decreased from a mean 3.25 +/- 0.53 D to 1.75 +/- 0.25 D. Therapeutic results: Keratoconus progression was stopped in 91.43% of eyes with a mean follow-up of 3.5 years and maximum follow-up of 6 years. PRK+PTK with the Nidek EC-5000 excimer laser was an excellent option for patients with primary keratoconus.

Artisan phakic iris claw intraocular lens for high primary and secondary hyperopia.

To evaluate the efficacy, predictability, and safety of the Artisan iris claw phakic intraocular lens for the correction of high primary and secondary hyperopia. Fifty-seven eyes were divided into two groups: 29 eyes had primary hyperopia (mean refraction 6.06 +/- 1.26 D, and 28 eyes had secondary hyperopia, (mean refraction 5.88 +/- 1.88 D) induced or residual following a previous corneal refractive procedure. Consecutive implantation of the Artisan iris claw phakic intraocular lens was performed. Main outcome measures recorded were BSCVA, UCVA, refraction, and astigmatic change, intraocular inflammation, and endothelial cell loss. Primary hyperopic group: Preoperatively, mean UCVA was 0.4 +/- 0.7 and mean BSCVA was 0.2 +/- 0.6. After implantation, mean UCVA was 0.3 +/- 0.6 and BSCVA was 0.1 +/- 0.6. Mean cycloplegic residual spherical refractive error after surgery was 0.10 +/- 0.57 D (range -1 to +2 D). Mean surgically induced astigmatism was 1.48 +/- 0.89 D. Safety index was 1.11. Efficacy index was 0.83. Secondary hyperopic group: Preoperatively, mean UCVA was 0.5 +/- 0.7 and mean BSCVA was 0.2 +/- 0.6. Postoperatively, mean UCVA was 0.4 +/- 0.7 and mean BSCVA was 0.2 +/- 0.6. Mean cycloplegic residual spherical refractive error was 0.55 +/- 1.49 D. Mean surgically induced astigmatism was 1.85 +/- 1.19 D. Safety index was 1.05. Efficacy index was 0.7. Postoperative iridocyclitis was observed in one eye (3.4%) in the primary group and in three eyes (10.7%) in the secondary group. Overall corneal endothelial cell loss at 1 year of follow-up was 9.4%. The Artisan iris claw phakic intraocular lens was reasonably safe and predictable for correcting high hyperopia.