Spectacle-corrected Visual Acuity Research Articles

Recurrence Characteristics on Optical Coherence Tomography and Treatments of Reis-Bücklers Corneal Dystrophy after Phototherapeutic Keratectomy or Penetrating Keratoplasty: Recurrence characteristics and treatments of RBCD

PurposeTo evaluate the recurrence characteristics on optical coherence tomography and clinical outcomes after phototherapeutic keratectomy (PTK) or penetrating keratoplasty (PKP) in patients with Reis-Bücklers corneal dystrophy (RBCD). DesignRetrospective interventional case series. MethodsSeventeen patients with RBCD (31 eyes, including six surgery-naïve eyes and 25 surgical eyes) received 44 surgical interventions from 1996 through 2022. PTK or PKP was performed as the initial surgical procedure. Significant recurrence was determined when best spectacle-corrected visual acuity decreased at least two lines with increased opacity in the superficial cornea. Repeated PTK or PTK on the corneal graft (CG-PTK) was considered if patients could not endure poor vision due to significant recurrence. Recurrence depth and annual increase in thickness of the central cornea and subepithelial deposits were assessed by anterior segment optical coherence tomography. ResultsThe mean follow-up time was 12.8±8.5 years (range, 2.0–25.5 years). The mean logMAR best spectacle-corrected visual acuity improved from 1.24±0.48 preoperatively to 0.27±0.09 postoperatively in the initial PTK group (13 eyes, P<0.001), from 1.84±0.69 to 0.40±0.13 in the PKP group (12 eyes, P<0.001), from 1.04±0.46 to 0.30±0.07 in the repeated PTK group (12 times in 7 eyes, P<0.001), and from 1.29±0.43 to 0.39±0.11 in the CG-PTK group (7 times in 5 eyes, P=0.001). The median significant recurrence time was 27 months (95% confidence interval 23.9-30.1), 96 months (84.1-107.9), 31 months (28.8-33.1), and 24 months (19.8-28.2), respectively (P<0.001). The depth of superficial deposits located between the epithelium and the anterior stroma was approximately 115μm (85-159μm). The annual thickening of subepithelial deposits was 14±2μm after initial PTK, 7±3μm after PKP, 14±3μm after repeated PTK, and 30±11μm after CG-PTK, compared to 4±2μm in surgery-naïve eyes (P=0.002, 0.515, 0.002, <0.001). The thickness of the central cornea increased by 15±2μm, 7±2μm, 15±3μm, and 31±10μm per year in the four surgery groups, respectively, compared to 5±2μm in surgery-naïve eyes (P=0.001, 0.469, 0.001, <0.001). ConclusionsBetter visual acuity can be achieved after PTK than PKP for treatment of RBCD. The annual thickening of subepithelial deposits may approximate an increase in central corneal thickness. The superficial distribution of subepithelial deposits makes it feasible to perform repeated PTK, even on the corneal allograft, for recurrent RBCD.

Conventional Epithelial-Off Corneal Crosslinking in Patients With Progressive Keratoconus: 10-Year Outcomes.

Corneal crosslinking (CXL) is the standard treatment of progressive keratoconus (KC). We evaluated the safety and 10-year outcomes of conventional "epithelial-off" CXL for progressive KC for the first time in a cohort in France. We conducted a retrospective review of patients undergoing conventional CXL (Dresden protocol) in our tertiary ophthalmology department from 2006 to 2011 with 10-year follow-up. The primary outcome was change in preoperative versus postoperative keratometry measured by maximum keratometry (Kmax), steep keratometry (K2), flat keratometry (K1), mean keratometry (Km), and topographic cylinder. Secondary outcomes were changes in visual and refractive outcomes. We report postoperative complications and adverse events. Eighty-nine eyes from 76 patients (67% male patients, mean age 22.7 ± 7.6 years) were included. Mean Kmax (-2.31 ± 2.98 diopters (D); P < 0.00001), K2 (-2.07 ± 3.15 D; P < 0.00001), K1 (-1.00 ± 2.29 D; P = 0.00008), Km (-1.53 ± 2.47 D; P < 0.00001), and topographic cylinder (-1.15 ± 2.53 D; P = 0.00004) significantly decreased 10 years after CXL compared with preoperative baseline. Significant decreases were still observed between 5 and 10 years after for mean Kmax, mean K2, mean K1, and mean Km. Mean distance best spectacle-corrected visual acuity and mean manifest refraction spherical equivalent were significantly improved after 10 years versus before CXL. The 10-year rate of repeat CXL was n = 3/76 patients (4%) (all younger than 18 years at first CXL) and of loss of >3 lines in best spectacle-corrected visual acuity was n = 1/76 patients (1%). Progressive KC was effectively stabilized with a prolonged flattening and maintenance of functional vision improvements after 10 years. Repeat CXL was rare and only required among younger patients.

Modified Method for Nanothin Descemet Stripping Automated Endothelial Keratoplasty.

The purpose of this study was to describe a method to achieve a high success rate for nanothin (NT, ≤50 μm) Descemet stripping automated endothelial keratoplasty (DSAEK) graft preparation using anterior chamber pressurizer (ACP) with a modified setting and evaluate its postoperative efficacy. A prospective cohort (study group) of 24 patients with corneal endothelial dysfunction was consecutively enrolled and received DSAEK grafts using the modified ACP method from December 2021 to May 2022. The control group included 24 historical patients who received DSAEK grafts using conventional ACP procedure. Central graft thickness (CGT), graft regularity (3-mm and 5-mm diameter zones), best spectacle-corrected visual acuity, and endothelial cell density (ECD) were compared between 2 groups. A 100% ultrathin (UT, ≤100 μm) DSAEK rate and 62.5% NT-DSAEK rate was achieved at 3 months postsurgery in the study group, with a 51.3 ± 14.8 μm CGT, while a 70.8% UT-DSAEK rate and 4.2% NT-DSAEK rate was achieved in the control group, with an 89.0 ± 15.4 μm CGT (P <0.001). At 3-month postoperative follow-up, the regularity of graft thickness was significantly better in the study group (central-to-peripheral thickness difference: P = 0.044 and 0.014 for 3-mm and 5-mm diameter zones, respectively, graft thickness uniformity: P <0.001 and 0.012, respectively). There was no statistical difference in the best spectacle-corrected visual acuity (P = 0.170) or ECD (P = 0.833) between 2 groups at 3-month postoperative follow-up. DSAEK grafts harvested using modified ACP method were thinner and more regular compared with the conventional ACP method.

Keratoconus characteristics and associations: A cross-sectional keratoconus study in western India (CKSWI).

To study the clinical and tomographic characteristics and associations of keratoconus (KC) patients visiting a tertiary eye care hospital. This was a cross-sectional, observational study that included 242 newly diagnosed clinical KC patients. Detailed ocular and systemic history, visual complaints, habit of eye rubbing, best spectacle-corrected visual acuity (BSCVA), retinoscopy reflex, detailed slit-lamp examination and tomographic findings, and presence of any ocular and systemic associations were documented for the included patients. Severity of KC was further graded into stages 0, 1, 2, 3, and 4 according to the ABCD grading system. The most common visual complaint was blurred vision (82.64%), followed by itching (48.76%), tearing (43.80%), and photophobia (41.32%). A total of 44.62% of patients had the habit of eye rubbing and 4.54% had a family history of KC. Most common clinical signs were scissor reflex (94.21%), Rizutti's sign (77.27%), corneal protrusion (69.83%), and Fleischer ring (67.35%). A total of 14.05% of patients had stage 0, 42.15% had stage 1, 19.83% had stage 2, 18.60% had stage 3, and 5.37% had stage 4 KC. Of these patients, 70.25% had a BSCVA visual acuity of ≥6/12 or better; 26.45% had a BSCVA of ≥6/60 to <6/12; and 3.30% had a BSCVA of <6/60. Ocular allergies, atopy, and asthma were found in 32.32%, 4.96%, and 2.48% cases, respectively. This study gives an overview of the clinical findings of KC cases in western India. Our results suggest that use of retinoscopy should be promoted in early KC detection in primary eyecare screening programs.

Clinical, Anatomical, and Densitometric Changes following Dresden vs. Accelerated Corneal Cross-Linking in Progressive Keratoconus.

To compare clinical, anatomical, and densitometric changes following Dresden (DCXL) vs. accelerated (ACXL) corneal UVA cross-linking (CXL; Avedro KXL, Geuder, Heidelberg, Germany) in progressive keratoconus (KC). In this retrospective study, we analyzed 20 patients following DCXL (3 mW/cm², 30 min, 5.4 J/cm²) and 44 patients following ACXL (9 mW/cm², 10 min, 5.4 J/cm²) between January 2016 and February 2020. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), steepest keratometry (Kmax), keratoconus index (KI), thinnest pachymetry (Pthin), and corneal densitometry (CD) were measured before and 3, 6, 12, and 24 months after CXL. During the follow-up period, no changes in UCVA, BSCVA, Kmax, KI, or Pthin occurred. CCT significantly decreased 3 months after DCXL (p = 0.032) and ACXL (p = 0.006). At the 12- and 24-month follow-up, CCT remained decreased in the DCXL (p = 0.035, 0.036, respectively) but not in the ACXL group. At the 12-month follow-up, the reduction in CCT was significantly greater in DCXL compared to ACXL (p = 0.012). At the 3-, 6-, 12-, and 24-month follow-ups, we found a significant increase in the anterior stroma CD following DCXL (p = 0.019, 0.026, 0.049, 0.047, respectively) but not ACXL. The CD changes were localized in the central concentric zones (0.0 to 6.0 mm). No intra- or postoperative complications occurred. ACXL and DCXL effectively halted KC progression. ACXL proved to be a safe time-saving alternative to conventional DCXL. DCXL led to a reduction in CCT and an increment in the CD of the central anterior stroma during 24 months of follow-up.

Donut-shaped Corneal Allogeneic Intrastromal Segment as an Alternative to Deep Anterior Lamellar Keratoplasty in Advanced Keratoconus.

The aim of this study was to describe a new technique of selective corneal stromal transplantation for keratoconus treatment, donut-shaped CAIRS (corneal allogeneic intrastromal ring segment). A donut-shaped corneal graft is obtained using a double-bladed trephine. Descemet membrane, endothelium, and epithelium are all removed from the graft. Only stromal tissue is transplanted. A wide 360-degree intrastromal tunnel is created using the femtosecond laser, with a 30-degree angulation. The diameter is from 5.4 mm to 8 mm optical zone. After dehydration, the corneal graft is inserted into the tunnel. We report the clinical and tomographic outcomes after the procedure in 3 patients. The mean follow-up time after donut-shaped CAIRS was 6.01 ± 1.02 months. In case 1, best spectacle-corrected visual acuity improved from 20/150 to 20/40. In case 2, it improved from 20/400 to 20/40, and in case 3 from 20/200 to 20/40. The mean preoperative K was 57.3 ± 4.5 D and reduced to 44.2 ± 2.5 D after donut-shaped CAIRS. The mean spherical equivalent decreased from -9.8 ± 3.2 preoperatively to -3.2 ± 2.2 postoperatively. No intraoperative or postoperative complications were observed. Anterior segment OCT showed a mid-stroma implant, fusiform in shape, equidistant from the epithelium and endothelium. Donut-shaped CAIRS is a variation of the traditional CAIRS technique and showed to be an alternative option for keratoconus treatment, especially in moderate to advanced cases with a central clear cornea without scars. The technique is minimally invasive, and the visual axis remains untouched.

The effect of pterygium on front and back corneal astigmatism and aberrations in natural-light and low-light conditions

BackgroundTo investigate the effect of different sizes of pterygium on the front and back corneal topography, refractive changes and aberrations in natural-light and low-light conditions.MethodsSixty subjects with unilateral primary nasal pterygium were enrolled in this study. All the patients’ uncorrected, best spectacle-corrected visual acuity, corneal topographic aberration data in 3 mm and 7 mm areas were collected. The pterygium size was evaluated by the slit-lamp photography and Sirius Scheimpflug Analyzer.ResultsThe front topographic astigmatism values, corneal total aberrations, and higher-order aberrations in 3 mm and 7 mm areas were higher in the pterygium group than those in the control group. The pterygium horizontal length and thickness were moderately to strongly correlated with astigmatism and RMS of aberrations, while pterygium vertical length showed no or just mild correlation with the corneal astigmatism and aberrations. Compared to the readings in 3 mm area, the front and back corneal astigmatism and aberrations were larger in 7 mm area.ConclusionsPterygium led to visual impairment by inducing astigmatism and aberrations. In low-light condition, the visual function worsened due to increased corneal astigmatism values and aberrations.

Descemet Endothelial Thickness Comparison Trial 1 (DETECT 1): outcome masked, placebo-controlled trial comparing two types of corneal transplant surgeries and effect of rho kinase inhibitors on endothelial cell loss protocol

BackgroundIt remains uncertain which endothelial keratoplasty (EK) technique yields the best outcomes while maintaining safety, particularly in eyes with coexisting ocular conditions. Moreover, the impact of endothelial cell loss (ECL)...

Surgical and visual outcomes of flap repositioning for various flap-related pathologies post laser in-situ keratomileusis (LASIK).

To evaluate the surgical and visual outcomes of flap repositioning for various post-laser-assisted in-situ keratomileusis (LASIK) flap pathologies. Retrospective review of consecutive cases between April 1, 2017 and February 28, 2022, where surgical flap repositioning was performed following LASIK for various flap-related complications. Of the 6018 eyes, 31 needed flap repositioning (0.51%). Indications were flap displacement and folds in 20 eyes (64%), flap subluxation in five eyes (16%), epithelial ingrowth and interface debris in two each, and one eye each of diffuse lamellar keratitis and incomplete flap. Final best spectacle-corrected visual acuity of ≥ 20/25 was obtained in 25/31 (80%) eyes. The efficacy index pre to post repositioning showed significant improvement (0.86 ± 0.39 vs. 0.63 ± 0.29 preop, P = 0.011). Flap repositioning incidence was significantly higher (7/602 (1.16%)) during the COVID lockdown phases compared to the non-COVID lockdown phase (24/5416 (0.44%, P = 0.019)). The COVID group had lower efficacy (0.72 ± 0.36 vs. 0.90 ± 0.39, P = 0.300) and safety indices (0.85 ± 0.24 vs. 1.06 ± 0.35, P = 0.144) compared to the non-COVID group; however, the results were not statistically significant. The flap displacement rate was statistically higher in nasal hinged (microkeratome) flaps (18/2013, 0.89%) compared to superior hinged (Femto) flaps (13/4005, 0.32%) (0.32%, P = 0.003). Our study shows that flap repositioning has a low incidence in LASIK, with the most common indication being flap displacement/folds. The outcome post flap repositioning was poorer during the lockdown period, perhaps due to the inability to follow up early. Early identification and surgical repositioning are successful in both anatomical and visual restoration.

The role of optical coherence tomography angiography in dome-shaped maculopathy

Purpose: To demonstrate the role of optical coherence tomography angiography (OCT-A) in the management of dome-shaped maculopathy (DSM). Methods: Retrospective case review. Results: A 52-year-old woman was referred to our retina service for potential bilateral choroidal neovascular membrane (CNVM) and blurry vision bilaterally. Initial spectacle-corrected visual acuity (VA) was 20/30-2 in the right eye (RE) and 20/30+2 in the left eye (LE). DSM was diagnosed on OCT. In both eyes, OCT B-scan passing through the fovea showed shallow, irregular RPE elevation (SIRE) suspicious of occult (type 1) CNVM. The outer retina and choriocapillaris angiograms showed a zone of nonexudative CNVM in the RE and exudative CNVM in the LE. Given the persistent SRF with CNVM in the LE, we elected to perform intravitreal injections of ranibizumab 0.5 mg on a treat and extend regimen. Upon the most recent follow-up, the best corrected VA improved to 20/20 in the LE with no persisting SRF. Conclusion: We present a case where assessing disease progression, the development of CNVM and evaluating the efficiency of therapies were realized through the application of novel OCT-A technology. This diagnostic tool may be used to guide clinicians in their management of DSM, as demonstrated through our experience. OCT-A can also make it possible to visualize nonexudative CNVM lesions that may be missed on traditional imaging assessments.

Deep Anterior Lamellar Keratoplasty Using Dehydrated versus Standard Organ Culture-Stored Donor Corneas: Prospective Randomized Trial

PurposeTo compare the outcomes of deep anterior lamellar keratoplasty (DALK) using dehydrated versus standard organ culture stored donor corneas for eyes with keratoconus. DesignProspective, randomized, single-center trial conducted in Italy ParticipantsAdult patients with keratoconus (≥ 18 years old) with keratoconus scheduled for an elective DALK MethodsCases with successful type 1 bubble pneumatic dissection using standard DALK technique were intraoperatively randomized to receive either dehydrated (n=30) or standard organ culture stored donor corneas (n=30). Main Outcome MeasuresThe primary study outcome was best spectacle-corrected visual acuity (BSCVA) 12 months after surgery. Secondary outcomes were refractive astigmatism (RA), endothelial cell density (ECD) and complication rates. ResultsPostoperative logMAR BSCVA did not significantly differ between groups at both time points (mean difference at 6 months = 0.030 [95%CI: -0.53-0.10] p = 0.471) and at 12 months = -0.013 [95%CI: -0.10-0.08] p = 0.764). No significant differences between groups were observed in terms of postoperative RA and ECD at all time points. In the first 3 days after DALK, an epithelial defect was present in 10 cases (33%) of the organ culture cornea group and in 29 cases (97%) of the dehydrated cornea group. Complete re-epithelialization was achieved by day 7 in all cases (100%) of both groups. ConclusionsThe study provides evidence that the use of dehydrated corneas is non-inferior to the use of standard organ culture donor corneas for DALK. Corneal tissue dehydration represents a viable solution that can allow long-term cornea preservation and avoid wastage of unused corneas.

Customized corneal allogenic intrastromal ring segments (CAIRS) for keratoconus with decentered asymmetric cone.

Corneal allogenic intrastromal ring segments (CAIRS) refer to the intracorneal placement of fresh, unprocessed, processed, preserved, or packaged allogenic rings/segments of any type/length. We described uniform-thickness CAIRS previously. We now describe a new technique of customized CAIRS to personalize the flattening effect as per individual topography. A prospective interventional case series of patients with pericentral/ paracentral decentered cones and gradation of keratometry with one side steeper than the other was conducted. Individually customized tapered CAIRS with variable volume, arc length, taper length, and gradient of taper were implanted. In total, 32 eyes of 29 patients with at least 1-year follow-up were included. Special double-bladed trephines and a CAIRS customizer template allowed the creation of individually customized CAIRS. Mean uncorrected distance visual acuity (UDVA) and spectacle-corrected distance visual acuity improved from 0.22 to 0.47 (P = 0.000) and from 0.76 to 0.89 (P = 0.001), respectively. Significant improvement was seen in K1, K2, Km, Kmax, topographic astigmatism, Q-value, sphere, cylinder, spherical equivalent, Root Mean Square (RMS), Higher Order Aberrations (HOA), and vertical coma (P < 0.01, 0.05). There was no significant change in the width or height of CAIRS between 1 month and last visit on anterior-segment optical coherence tomography. Five eyes continued to remain at the same UDVA, 27 eyes had at least 2 lines, and 13 eyes had at least 3 or more lines improvement in UDVA. The maximum improvement in UDVA was 7 lines. A significant difference in flattening was obtained at different zones across the tapered CAIRS. Thus, differential flattening was achieved across the cone based on the customization plan. Personalized customization was possible for each cornea, unlike limited models of progressive-thickness synthetic segments. Allogenic nature, greater customizability, efficacy, and absent need for large inventories are advantages compared to synthetic segments.

Effectiveness of toric soft contact lenses for vision correction in patients with different degrees of astigmatism: a real-world study.

To assess the visual correction of patients with different degrees of astigmatism with toric soft contact lenses (TSC). It was a real-world study with prospective and single-arm design. A total of 384 patients with astigmatism who came for TSC fitting and alignment from November 2022 to January 2023 were included. According to the difference in astigmatism, patients were divided into groups A (cylinder degree: -0.75 to -0.50 D), B (cylinder degree: -1.75 to -1.00 D) and C (cylinder degree ≤ -2.00 D), and followed up on the day of wear, 1wk, 1 and 3mo, mainly to observe visual acuity, refraction, lens fit, visual quality and comfort at 1wk after wear. The visual acuity success rate and the overall success rate of the fitting were evaluation indicators (taking into account the four dimensions of visual acuity, fitting, quality of vision and comfort). The visual acuity success rate was calculated by taking "corrected visual acuity with contact lenses is no less than 1 line or better than best spectacle-corrected visual acuity" (i.e. corrected visual acuity with contact lenses is 1 line below, equal to, one line above or more than best spectacle-corrected visual acuity) as the criterion for visual success, and the the overall success rate of the fitting was calculated by using the comprehensive indicators (visual acuity, fit, visual quality, comfort) to meet certain conditions as the judgment criteria for successful fitting. After 1wk of wearing TSC, the visual acuity success rates of patients were 100% (207/207), 98.58% (139/141) and 97.22% (35/36) in the three groups, respectively, with residual cylinder closed to 0. The acceptability of the lens fitting was over 95%; the incidence of adverse visual symptoms was within 10% and the comfort acceptability was over 97%. The overall success rate of fitting for patients with high, medium and low astigmatism was 93.72% (194/207), 90.78% (128/141) and 88.89% (32/36), respectively. TSC (model: G&G POP·CT) are effective in correcting astigmatism in patients with different degrees of astigmatism.

Development of a Web-Based Algorithm for Understanding the Intraocular Lens-Based Surgery in Stable and Progressing Keratoconus for Non-Specialist Ophthalmologists

Purpose To propose an algorithm to facilitate lens-based surgery in keratoconus. Methods A literature review was performed to prepare a software algorithm based on cone location, stability, best spectacle-corrected distance visual acuity (BSCVA) level and whether there is a clear or cataractous lens. The software usability was assessed through a 10-question questionnaire and two hypothetical keratoconus case histories (moderately simple and moderately complex) given to 15 trainees. The usability questionnaires were graded on a Likert scale (1 = strongly disagree to 5 = strongly agree) and two case histories (1 = very difficult to 7 = very easy). Results The algorithm can be found at https://www.sussexeyelaserclinic.co.uk/keratoconus/. Thirteen trainees completed the questionnaire. 91.9% would frequently use it; for 100%, it was easy to use independently without technical support; for 63.7%, it was strongly integrated; for 100%, it was consistent; 100% thought that most people would learn to use it quickly, 91.9% found the system not cumbersome to use, felt very confident to use it and need not learn a lot to use it. The first case was found easy by 63.7% and the second by 45%. Conclusion We present an algorithm as a guide for lens-based surgery in stable and progressing keratoconus, which is classified based on cone location. This algorithm will help trainee and “non-specialist” ophthalmic surgeons understand the pre-operative planning for the surgery and referral to the “specialist” corneal surgeon, considering factors such as progression, BSCVA, keratometry, topography and apex location of the cone in keratoconus patients.

Outcomes of large-diameter deep anterior lamellar keratoplasty and converted two-piece mushroom penetrating keratoplasty for herpetic corneal scars.

To report the clinical outcomes of large diameter deep anterior lamellar keratoplasty (DALK) and converted two-piece microkeratome-assisted mushroom keratoplasty (MK) for herpetic corneal scars. In this single-centre study, large diameter (9 mm) DALK was attempted in consecutive patients with herpetic corneal scars. In case of macroperforation or unsatisfactory clearance of the optical zone, the procedure was intraoperatively converted to two-piece microkeratome-assisted MK. Outcome measures were best spectacle-corrected visual acuity (BSCVA), refractive astigmatism, endothelial cell density (ECD), immunologic rejection, herpetic recurrence and graft failure rates in the two groups. DALK was successfully performed in 98 of 120 eyes, while the remaining 22 eyes required intraoperative conversion to MK. At 5 years, mean logMAR BSCVA was 0.10 ± 0.12 in the DALK group and 0.09 ± 0.15 in the MK group (P = 0.75). Refractive astigmatism at 5 years was 2.8 ± 1.4 D in the DALK group and 3.0 ± 1.7 D in the MK group (P = 0.67). ECD was higher in the DALK group than in the MK group at all time points (P < 0.001), with a mean annual cell loss of 10.9% after MK and 4.2% after DALK. The 5-year risk for immunologic rejection (DALK: 3%, MK: 5%, P = 0.38), herpetic recurrence (DALK: 6%, MK: 9%, P = 0.38), and graft failure (DALK: 4%, MK: 5%, P = 0.75) were comparable in both groups. Large diameter (9 mm) DALK yields excellent visual and clinical outcomes in eyes with herpetic corneal scars. In case of intraoperative complications, DALK can be converted to two-piece microkeratome-assisted MK to maximize the refractive benefit of a large diameter graft while minimizing the risk of endothelial failure.

Ray-Tracing Transepithelial Excimer Laser Central Corneal Remodeling Plus Pachymetry-Guided Accelerated Corneal Crosslinking for Keratoconus.

The aim of this study was to report the 12 to 96 months results of a tissue-preservation algorithm based on ray-tracing-guided transepithelial excimer laser central corneal ablation (RT t-PRK) combined with individualized pachymetry-guided accelerated crosslinking (M nomogram ACXL) in young adult patients with stable keratoconus (KC). This was a prospective interventional study including 38 eyes of 38 young adult patients (stage II KC) with a mean age of 35 years (range 26-46 years) who underwent simultaneous RT with t-PRK plus pachymetry-based ACXL in the worst eye. The treatments were performed using the iViS Suite iRES Excimer Laser (Ligi, Taranto, Italy). Ray-tracing-guided treatments were planned using the customized interactive programmed transepithelial ablation (CIPTA) 2 web software and diagnostic data were assessed by the Precisio 2 tomographer (Ligi, Taranto, Italy) and Sirius tomographer (C.S.O., Florence, Italy). The main outcome measures included uncorrected distance visual acuity, best spectacle-corrected visual acuity, Kmax, high-order aberrations, minimum corneal thickness, and posterior elevation, with a mean follow-up of 52 months (range 12-96 m). The mean UDVA improved + 3.5 ±1.28 Snellen lines (SL); 38% gained ≥ 4 ±1.34 SLs, 35% ≥ 3 ±1.21 SLs, 22% ≥ 2 ±1.12 SLs, and 5% ≥ 1 ±0.75 SLs. The mean best spectacle-corrected visual acuity increased by + 4.3 ±1.3 SL. Sixty-eight percent gained ≥ 4 ±0.88 SLs and 30% ≥ 3 ±0.78 SL. No SLs were lost. RT t-PRK plus ACXL significantly improved the quality of vision in patients with KC, preventing overcorrection and minimizing tissue consumption.

Less Complex Contact Lens Required for a Patient With Keratoconus After Topography-Guided Photorefractive Keratectomy.

In this report, we discuss contact lens (CL) fitting in a patient with a history of keratoconus (KC), before and after undergoing topography-guided photorefractive keratectomy (TG PRK). Before TG PRK, the patient failed multiple CL modalities and reported difficulty with his habitual CLs and inadequate spectacle-corrected visual acuity to perform his activities of daily living. In this case, a collaborative, comprehensive approach to visual management in a patient with KC was used, and after TG PRK was performed to improve his corneal contour and symmetry, our patient was fit with a standard soft CL and additionally had improved spectacle-corrected visual acuity.

Quantitative evaluation of corneal irregularity and scarring after infectious keratitis using anterior segment optical coherence tomography

PurposeCorneal scars after infectious keratitis lead to insufficient transparency and irregular astigmatism, affecting visual acuity; therefore, they should be accurately evaluated to estimate visual function. This study aimed to quantitatively evaluate corneal irregularity and scarring after infectious keratitis using anterior segment optical coherence tomography (AS-OCT).MethodsThis was an observational clinical study. We included patients who had corneal scarring after treatment of infectious keratitis between 2014 and 2021 at University of Tokyo Hospital. We retrospectively examined best spectacle-corrected visual acuity (BSCVA), average keratometric power, central corneal thickness (CCT), and four components of the Fourier harmonic analysis including spherical and asymmetry components, as well as regular astigmatism and higher-order irregularity. We included anterior and posterior corneal data and compared results with those of contralateral healthy eyes. Additionally, we quantitatively evaluated the densitometry of the cornea obtained using AS-OCT.ResultsA total of 122 eyes of 61 patients were examined; male predominance was observed (n = 37), and the mean patient age was 55.3 ± 19.4 years. Comparisons with contralateral healthy eyes showed that BSCVA worsened (0.30 ± 0.83 and 0.93 ± 1.36 logMAR, respectively, P = 0.003), and CCT (531.1 ± 46.2 and 591.8 ± 132.4 μm, respectively, P < 0.001) and corneal densitometry (84.4 ± 11.8 and 111.9 ± 19.2 grayscale units, respectively, P < 0.001) increased significantly in affected eyes. The asymmetry component and higher-order irregularities that were not corrected with spectacles significantly increased (both P < 0.001), and there were no significant differences in the changes among the bacterial, fungal, herpetic, and acanthamoeba types of keratitis.ConclusionCorneal scarring persisted after treatment for infectious keratitis, and the asymmetry and irregularities of corneal astigmatism increased as visual acuity deteriorated. AS-OCT with the Fourier harmonic analysis was useful for evaluating corneal topographic changes in patients with corneal scarring after keratitis.

Effects of Custom-Designed Soft Contact Lenses on Irregular Astigmatism Correction in Patients with Keratoconus.

To evaluate the efficacy of YOUSOFT soft contact lenses in correcting irregular astigmatism and prescription results of patients with keratoconus. The retrospective observational study included 55 eyes (mean age, 32.2 ± 10.6 years; 36 men and 6 women) of 42 patients with keratoconus who tried YOUSOFT for rigid gas permeable (RGP) lens intolerance. Average keratometry, corneal astigmatism, and maximum keratometry were 49.4 ± 5.2 diopters (D), 3.7 ± 2.1 D, and 57.3 ± 8.2 D, respectively. Patients were divided into YOUSOFT prescription and non-prescription cases, wherein the prescription rates were calculated. YOUSOFT visual acuity was compared with spectacle-corrected distance visual acuity (CDVA) and RGP lens-CDVA. YOUSOFT was prescribed to 28 out of 42 patients (prescription rate 67%). In the YOUSOFT prescription cases, YOUSOFT-CDVA (logMAR -0.04; 95% confidence interval [CI]: -0.08 to 0.00) was significantly better than spectacle-CDVA (logMAR 0.23; 95% CI: 0.08 to 0.38; P < 0.0001), whereas YOUSOFT-CDVA (logMAR -0.03; 95% CI: -0.08 to 0.03) did not significantly differ from the RGP lens-CDVA (logMAR -0.02; 95% CI: -0.08 to 0.04; P = 0.856). YOUSOFT was effective in correcting irregular corneal astigmatism, suggesting that it is highly effective in patients with RGP lens intolerance.

Donor lamella thickness after ultrathin Descemet stripping automated endothelial keratoplasty and its relation to postoperative visual acuity and pre-operative lamella measures

BackgroundTo accurately measure ultrathin Descemet stripping automated endothelial keratoplasty (DSAEK) donor lamella thickness during the first postoperative year and to correlate this with pre-operative and other postoperative measurements.MethodsDonor lamella thickness in 41 eyes undergoing DSAEK for Fuchs endothelial dystrophy (FED) was measured using the Tomey Casia OCT directly after graft preparation and at 1 week and 1, 3, 6 and 12 months postoperatively. Visual acuity and endothelial cell density were measured as the secondary parameters.ResultsIndividual graft thickness profiles were shown to be fairly regular within the optically relevant area. There was a strong and highly significant correlation between the pre- and postoperative lamellar thicknesses at all time points (p < 0.0001). Compared with the measurements directly after preparation at the cornea bank, the lamella thickness decreased by 12% after 12 months. Between 1 and 12 months postoperatively, the lamella thickness (mean ± SD) changed from 112 ± 27 μm to 101 ± 21 μm. Best spectacle-corrected visual acuity (BSCVA) changed from 0.46 ± 0.30 logMAR pre-operatively through 0.36 ± 0.33 at 1 month to 0.13 ± 0.16 at 1 year postoperatively. The endothelial cell counts were comparable to those reported in previous studies.ConclusionsThickness profiles of individual grafts were fairly regular within the optically relevant area. A strong relationship between pre- and postoperative graft thicknesses was detected, and ultrathin DSAEK grafts prepared using methods similar to that applied in this study are expected to show a deswelling of around 12% during the first postoperative year. No correlation was detected between graft thickness and BSCVA.