Iatrogenic Keratectasia after Refractive Surgery - Causes, Prophylaxis, Therapy. / Iatrogene Keratektasie nach refraktiver Chirurgie ­ Ursachen, Prophylaxe, Therapie.

Iatrogenic keratectasia is induced thinning and protrusion of the cornea after laser refractive surgery. Known risk factors include an excessively thin postoperative residual stromal bed, a thicker flap, or preoperatively undetected evidence of preexisting subclinical keratoconus. The rate of post-refractive ectasia in eyes without identifiable preoperative risk factors is 20 per 100 000 eyes for photorefractive keratectomy, 90 per 100 000 eyes for laser in situ keratomileusis, and 11 per 100 000 eyes for small incision lenticule extraction. Traditional screening tools for preoperative risk include the ectasia risk score system and percentage of tissue alteration. More recent methods include corneal elastography and epithelial mapping, in addition to Artificial Intelligence methods for data analysis. Therapy includes contact lenses, cross-linking, implantation of intracorneal ring segments, penetrating or lamellar keratoplasty, and, in early studies, implantation of corneal lenticules.

The impact of perinatal brain injury on retinal nerve fiber layer thickness and optic nerve head parameters of premature children.

PURPOSE: This study aims to evaluate the impact of birth weight (BW), gestational age (GA), retinopathy of prematurity (ROP), and perinatal brain injury (PBI) on optic nerve head (ONH) parameters and nerve fiber layer thickness (RNFLT) in preterm children. METHODS: ONH parameters and RNFLT were examined prospectively in 5-15-year-old preterm and full-term children with RTVue-100 OCT (Optovue, USA). The parameters of the two groups were compared and possible influences of BW, GA, ROP, and PBI analyzed in preterm children. RESULTS: In total, 51 full-term and 55 preterm children were included. The mean age was 9.98 ± 3.4 years in full-term and 10.0 ± 2.5 years in preterm children. The mean GA in preterm children was 29.6 ± 3.8 weeks with a BW of 1523 ± 732 g. RNFLT was significantly lower in preterm than in full-term children in all but temporal quadrants. Cup area, volume, cup/disc area ratio, and horizontal cup/disc ratio (CDR) were significantly larger and rim area significantly thinner in preterm children. GA was positively correlated with superior, nasal, and overall RNFLT and negatively correlated with cup area, volume, and horizontal CDR. ROP stage correlated negatively with superior and nasal RNFLT. PBI was the only significant predicting factor for RNFL thinning in all but temporal quadrant in multiple regression analysis. Preterm children with PBI had a significantly larger optic cup (CDR 0.70 ± 0.33 vs. 0.37 ± 0.27) and thinner optic rim. CONCLUSION: PBI correlated strongest with RNFL thinning, a thinner optic rim, and a larger optic cup in preterm children and should be evaluated in each patient to prevent incorrect diagnosis like glaucoma.

Comparison of intraocular lens power calculation formulas with and without total keratometry and ray tracing in patients with previous myopic SMILE.

PURPOSE: To evaluate the prediction error (PE) variance and absolute median PE of different intraocular lens (IOL) calculation formulas including last-generation formulas such as Barrett True-K with K, Okulix and total keratometry (TK)-based calculations with Haigis, and Barrett True-K in a simulation model in post-small-incision lenticule extraction (SMILE) eyes. SETTINGS: Department of Ophthalmology, University Hospital Marburg, Marburg, Germany. DESIGN: Prospective study. METHODS: Preoperative measurements included IOL power calculation before and after SMILE surgery. The target refraction was set to be the lowest myopic refractive error in pre-SMILE eyes. The IOL power targeting at the lowest myopic refractive error in pre-SMILE eyes was selected for the post-SMILE IOL calculation of the same eye. The difference between the predicted refraction of pre- and post-SMILE eyes with the same IOL power was defined as IOL difference. The refractive change induced by SMILE was defined as the difference between preoperative and postoperative manifest refraction. RESULTS: 98 eyes from 49 patients underwent bilateral myopic SMILE. The PE variance of Okulix was not significantly different compared with Barrett True-K with TK ( P = .471). The SDs of the mean PEs were ±0.413 D (Haigis-TK), ±0.453 D (Okulix), ±0.471 D (Barrett True-K with TK), ±0.556 D (Haigis-L), and ±0.576 D (Barrett True-K with K). The mean absolute PE was 0.340 D, 0.353 D, 0.404 D, 0.511 D, and 0.715 D for Haigis-TK, Okulix, Barrett True-K with TK, Barrett True-K with K, and Haigis-L, respectively. The highest percentage of eyes within ±0.50 D was achieved by Okulix, followed by Haigis-TK, Barrett True-K with TK, Barrett True-K with K, and Haigis-L. CONCLUSIONS: Results suggest that Haigis in combination with TK, Okulix, and Barrett True-K with and without TK offer good options for accurate IOL power calculation after SMILE. Haigis-L showed a tendency for myopic shift in eyes after previous SMILE.

Long-term surgical outcomes of two different Ahmed Valve implantation techniques in refractory glaucoma: Scleral flap vs scleral tunnel.

PURPOSE: To compare the outcomes and complications of the partial-thickness scleral flap technique to the long scleral tunnel technique in patients who underwent mitomycin C (MMC)-augmented Ahmed glaucoma valve (AGV) implantation. PATIENTS AND METHODS: In this retrospective study, we reviewed 139 eyes of 137 patients with refractory glaucoma who underwent AGV-Model FP7 implantation. The eyes were divided into the scleral flap group (n = 74) and the scleral tunnel group (n = 65). RESULTS: The mean follow-up was 57.91 ± 18.18 months for the flap and 61.18 ± 15.13 months for the tunnel group (p = 0.2499). The postoperative intraocular pressure (IOP) at 1 to 6 years was significantly lower than the baseline IOP in each group (p < 0.001). The average number of postoperative glaucoma medications decreased in the tunnel group (p = 0.0001) and in the flap group (p = 0.6194) compared to baseline. No statistically significant differences in postoperative visual acuity (p = 0.6396) and cumulative success (p = 0.054) were noted between the two groups. Conjunctival erosion or tube migration only occurred in the flap group. Significantly more reoperations were performed in the flap than in the tunnel group (p = 0.048). CONCLUSIONS: Both MMC-augmented AGV tube implantation methods lowered IOP. The flap technique was associated with higher rates of postoperative serious complications and more reoperations than the tunnel technique. Previous glaucoma surgery and the technique used to implant the surgical tube proved to be significant risk factors for conjunctival erosion.

SMILE for Hyperopia With and Without Astigmatism: Results of a Prospective Multicenter 12-Month Study.

PURPOSE: To investigate the safety and effectiveness of small incision lenticule extraction (SMILE) in patients who have hyperopia with or without astigmatism. METHODS: This was a prospective multicenter trial including 374 eyes of 199 patients treated by SMILE for hyperopia using the VisuMax femtosecond laser (Carl Zeiss Meditec AG). Inclusion criteria were sphere up to +6.00 diopters (D), cylinder up to 5.00 D, and maximum hyperopic meridian up to +7.00 D, with preoperative corrected distance visual acuity (CDVA) of 20/25 or better. The optical zone was 6.3 mm with a transition zone of 2 mm. The minimum lenticule thickness was set at 25 µm in the center and at 10 µm at the edge. Patients were examined at 1 day, 1 week, and 1, 3, 6, 9, and 12 months after surgery. Standard refractive surgery outcomes analysis was performed. RESULTS: The preoperative spherical equivalent was +3.20 ± 1.48 D (range: +0.25 to +6.50 D). At the 12-month follow-up visit, 81% of eyes treated were within ±0.50 D and 93% of eyes were within ±1.00 D of intended correction. A total of 1.2% of eyes lost two or more lines of CDVA at the 12-month follow-up visit, and 83% were at least 20/20, corresponding to a safety index of 1.005 at 12 months. Of the 219 eyes with plano target, 68.8% had an uncorrected distance visual acuity of 20/20 or better and 88% were at least 20/25 uncorrected at 12 months. There were no statistically significant changes in contrast sensitivity. CONCLUSIONS: SMILE was found to be an effective treatment method for the correction of compound hyperopic astigmatism, demonstrating a high level of efficacy, predictability, safety, and stability. [J Refract Surg. 2022;38(12):760-769.].

Twelve-year global publications on small incision lenticule extraction: A bibliometric analysis.

Purpose: To analyze the development process of small incision lenticule extraction (SMILE) surgery in a 12-year period. Methods: We conducted a literature search for SMILE research from 2011 to 2022 using the Science Citation Index Expanded (SCIE) of the Web of Science Core Collection (WoSCC). The VOS viewer, and CiteSpace software were used to perform the bibliometric analysis. Publication language, annual growth trend, countries/regions and institutions, journals, keywords, references, and citation bursts were analyzed. Results: A total of 731 publications from 2011 to 2022 were retrieved. Annual publication records grew from two to more than 100 during this period. China had the highest number of publications (n = 326). Sixty-five keywords that appeared more than four times were classified into six clusters: femtosecond laser technology, dry eye, biomechanics, visual quality, complications, and hyperopia. Conclusion: The number of literatures has been growing rapidly in the past 12 years. Our study provides a deep insight into publications on SMILE for researchers and clinicians with bibliometric analysis for the first time.

IOL Power Calculations and Cataract Surgery in Eyes with Previous Small Incision Lenticule Extraction.

Small incision lenticule extraction (SMILE), with over 5 million procedures globally performed, will challenge ophthalmologists in the foreseeable future with accurate intraocular lens power calculations in an ageing population. After more than one decade since the introduction of SMILE, only one case report of cataract surgery with IOL implantation after SMILE is present in the peer-reviewed literature. Hence, the scope of the present multicenter study was to compare the IOL power calculation accuracy in post-SMILE eyes between ray tracing and a range of empirically optimized formulae available in the ASCRS post-keratorefractive surgery IOL power online calculator. In our study of 11 post-SMILE eyes undergoing cataract surgery, ray tracing showed the smallest mean absolute error (0.40 D) and yielded the largest percentage of eyes within ±0.50/±1.00 D (82/91%). The next best conventional formula was the Potvin-Hill formula with a mean absolute error of 0.66 D and an ±0.50/±1.00 D accuracy of 45 and 73%, respectively. Analyzing this first cohort of post-SMILE eyes undergoing cataract surgery and IOL implantation, ray tracing showed superior predictability in IOL power calculation over empirically optimized IOL power calculation formulae that were originally intended for use after Excimer-based keratorefractive procedures.

Corneal opacities after small-incision lenticule extraction.

A 36-year-old woman was referred to our clinic in October 2021 with suboptimal vision at intermediate and near distances and halos and photophobia after a small-incision lenticule extraction (SMILE) in December 2019. The patient needs to increase font size of her computer to 150% to read text, but images still appear blurred. She indicates that sunglasses seem to improve her contrast. Preoperatively, her refractive error was -2.5 diopters (D) and -2.25 D for right and left eyes. The optical zone size of the SMILE procedure was 6.8 mm. There is no further information available on the peroperative course of the SMILE procedure. Her uncorrected distance visual acuity (UDVA) is 20/20 in both eyes and does not improve with correction. The Schirmer tear test is 14 to 13 mm. Slitlamp biomicroscopy of the right eye and the left eye reveals hyperreflective small opacities in the anterior one-third of the corneal stroma ( Figures 1 and 2JOURNAL/jcrs/04.03/02158034-202209000-00021/figure1/v/2022-08-29T115553Z/r/image-tiffJOURNAL/jcrs/04.03/02158034-202209000-00021/figure2/v/2022-08-29T115553Z/r/image-tiff ). No other abnormalities are seen. The scotopic pupil sizes are 6.41 and 6.73 mm. Straylight measurements are within normal limits. Higher-order aberrations (HOAs) measure for the right eye (6.03 mm pupil) 0.818 µm and for the left eye (6.17 mm pupil) 0.560 µm. The corneal Scheimpflug tomography quad maps for both eyes are shown in Supplemental Figures 1 and 2 ( http://links.lww.com/JRS/A663 , http://links.lww.com/JRS/A664 ). What is your diagnosis or are additional diagnostic methodologies needed to establish a diagnosis? What is your treatment advice for this patient?

Five-year follow-up of corneal morphology and corneal refractive power changes after uneventful DMEK.

PURPOSE: To investigate changes of corneal thickness spatial profile (CTSP), corneal volume (CV) distribution, and total corneal refractive power (TCRP) over a course of 60 months after uneventful Descemet membrane endothelial keratoplasty (DMEK). METHODS: In our prospective, comparative study, sixty DMEK cases without intraoperative and postoperative complications and with complete 60-month follow-up were included (group 1). CTSP at corneal apex (CCT) and at 2 mm, 4 mm, 6 mm, and 8 mm rings, CV in 3 mm, 5 mm, 7 mm, and 10 mm zones, and TCRF in 2 mm, 4 mm 6 mm, and 8 mm zones were evaluated preoperatively and at 3, 6, 12, 24, and 60 months postoperatively. The 60-month results were compared to an age-matched group of uncomplicated pseudophakic eyes (group 2; n = 20). RESULTS: The CCT and CTSP at 2, 4, and 6 mm increased significantly at 60 months compared to 3-month outcomes (P < 0.001). Similarly, CV increased significantly in 3 mm, 5 mm, and 7 mm zones at 60 months compared to 3 months outcomes (P < 0.001). The TCRP showed in all zones a significant decrease at 3 months (P < 0.001) followed by a continuous and significant increase at 60 months (P < 0.001). The 60-month CCT and CTSP at 2 mm were similar to group 2 (P ≥ 0.094). CONCLUSION: Sixty months after uneventful DMEK, CT within the central 2 mm zone and CV at 3 mm zone were similar to uncomplicated pseudophakic eyes. A continuous and statistically significant increase of TCRP was observed in all measured zones after the 3-month examination.

[Reasons and risk factors for recurrent retinal detachment after removal of silicon oil in various vitreoretinal diseases]. / Ursachen und Risikofaktoren für eine erneute Netzhautablösung nach Silikonölentfernung bei verschiedenen vitreoretinalen Grunderkrankungen.

BACKGROUND: Pars plana vitrectomy (ppV) combined with silicone oil tamponade is a standard technique in the treatment of complicated retinal detachment. There are still recurrent cases of retinal detachment after silicone oil removal or redetachment with in situ oil tamponade. OBJECTIVE: The aim was to identify possible risk factors for retinal redetachment and to use the knowledge for optimizing treatment. METHODS: Analysis of data from patients who were treated with ppV and silicone oil tamponade in the University Department of Ophthalmology in Marburg during 2010-2015 and who had a retinal redetachment during this period. The results were divided into two groups, redetachment with oil in situ and redetachment after oil removal. RESULTS: A total of 43 cases (15.6%) had a redetachment, which included 22/43 cases (50%) with a redetachment after oil removal and 21/43 cases (50%) with redetachment with oil in situ. The cause for the renewed detachment was given as proliferative vitreoretinopathy (PVR) in 90.6% (39/43) of the cases, new foramina in 20.9% (9/43) and persisting foramina in 25.5% (11/43). CONCLUSION: Vitreoretinal scar formation (PVR reaction) was the main risk factor for renewed retinal detachment. Persisting foramina were also named as a frequent cause. Recurrent retinal detachment represents a significant challenge for vitreoretinal surgeons and for the patients considering the economic and emotional burden due to multiple interventions.

Corneal Densitometry After Uneventful Descemet Membrane Endothelial Keratoplasty-5-Year Outcomes.

PURPOSE: The purpose of this study is to analyze the course of corneal densitometry (CD), endothelial cell density (ECD), best-corrected visual acuity (BCVA), and central corneal thickness (CCT) 5 years after uneventful Descemet membrane endothelial keratoplasty (DMEK). METHODS: Sixty uneventful cases (51 patients) with a minimum follow-up of 5 years were included. CD of various corneal layers (anterior, central, posterior, and total layer) and zones (0-2 mm, 2-6 mm, and 6-10 mm) were measured with Scheimpflug tomography. ECD, BCVA, and CCT were also evaluated. RESULTS: Total CD at 0 to 2 mm and 2 to 6 mm zones significantly decreased from 33 ± 10 and 27.8 ± 8 grayscale units (GSU) preoperatively to 21.8 ± 3.1 and 22.2 ± 4.2 GSU at 5 years, respectively ( P < 0.001). On the contrary, total CD at the 6 to 10 mm zone significantly increased from 30 ± 8.3 GSU preoperatively to 34.6 ± 7.8 GSU at 5 years ( P < 0.001). ECD significantly decreased from 2496 ± 267 cells/mm 2 preoperatively to 1063 ± 470 cells/mm 2 at 5 years ( P < 0.001). Similarly, CCT significantly decreased from 686 ± 109 µm preoperatively to 557 ± 37 µm at 5 years ( P < 0.001). Postoperative BCVA was significantly better after DMEK for every examination time point. CONCLUSIONS: Despite a slight CD increase at all layers of all corneal zones from the second to the fifth postoperative year, the excellent visual outcome was maintained throughout 5-year follow-up. Thus, DMEK seems to effectively treat corneal endothelial disease in the long term.

Corneal Remodeling After Myopic SMILE Versus FS-LASIK: A Spatial Analysis of Short- and Mid-Term Corneal Thickness, Volume, and Shape Changes.

PURPOSE: To evaluate the short- and mid-term changes of corneal thickness spatial profile (CTSP), corneal volume distribution (CVD), and corneal asphericity after small-incision lenticule extraction (SMILE) for correction of myopia and astigmatism and compare the results with femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). METHOD: Thirty eyes of 18 patients who underwent SMILE were compared with a group of 30 eyes of 16 patients who underwent FS-LASIK. The groups were matched for preoperative central corneal thickness and lenticule thickness/ablation depth. Scheimpflug corneal tomography was performed preoperatively and postoperatively at 2 months and 3 years. The CTSP was evaluated on 4 concentric rings (2, 4, 6, and 8 mm). The CVD was evaluated at 3 concentric zones (3, 5, and 7 mm). Changes in the anterior and posterior asphericity at a 6-mm zone were also evaluated. RESULTS: Between the 2-month and 3-year examination, the CTSP showed a similar increase for both groups at all measured points and rings ( P ≥ 0.168). The CVD also showed a similar increase for both groups at all measured zones ( P ≥ 0.278). The anterior corneal asphericity remained stable after SMILE (2-mo Q = 0.46 ± 0.27; 3-yr Q = 0.45 ± 0.27; P = 0.711) but decreased significantly after FS-LASIK (2-mo Q = 0.52 ± 0.47; 3-yr Q = 0.47 ± 0.44; P = 0.028). Similarly, the posterior corneal asphericity remained stable after SMILE (2-mo Q = -0.11 ± 0.15; 3-yr Q = -0.11 ± 0.13; P = 0.902) but decreased significantly after FS-LASIK (2-mo Q = -0.13 ± 0.14; 3-yr Q = -0.16 ± 0.15; P = 0.034). CONCLUSIONS: CTSP and CVD between the 2-month and 3-year examination showed a similar increase after SMILE and FS-LASIK. During the postoperative course, the anterior and posterior corneal asphericity remained more stable after SMILE compared with FS-LASIK.

Hyperopic SMILE Versus FS-LASIK: A Biomechanical Comparison in Human Fellow Corneas.

PURPOSE: To investigate the biomechanical properties of ex vivo human paired corneas after hyperopic correction via cap-based versus flap-based laser-assisted refractive surgery. METHODS: In this prospective experimental study, 13 pairs of human corneas unsuitable for transplantation were equally divided into two groups. The pachymetry was performed in each eye just before the laser procedure. Corneas from the right eye were treated with small incision lenticule extraction (SMILE), whereas corneas from the left eye of the same donor were treated with femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). All corneas were subjected to a refractive correction of +6.00 diopters (D) sphere with a 6.5-mm zone under a 120-µm cap (SMILE) or a 7-mm zone under a 110-µm flap (FS-LASIK). For two-dimensional biomechanical measurements, the corneoscleral buttons underwent two testing cycles (preconditioning stress-strain curve from 0.03 to 9.0 N and stress-relaxation at 9.0 N during 120 seconds) to analyze the elastic and viscoelastic material properties. The effective elastic modulus was calculated. Statistical analysis was performed with a confidence interval of 95%. RESULTS: In stress-strain measurements, the effective elastic modulus was not significantly different (P > .311) between SMILE (13.5 ± 12.8 MPa) and FS-LASIK (7.56 ± 17.9 MPa). In stress-relaxation measurements, the remaining stress was not significantly different (P = .841) between SMILE (124 ± 20 kPa) and FS-LASIK (126 ± 21 kPa). CONCLUSIONS: Unlike myopic correction, after hyperopic correction the cap-based procedure (SMILE) and the flap-based technique (FS-LASIK) may be considered equivalent in terms of biomechanical stability when measured experimentally in ex vivo human fellow eye corneas. [J Refract Surg. 2021;37(12):810-815.].

Patient-Reported Quality of Life and Satisfaction After Refractive Lens Extraction Using a Diffractive Trifocal IOL: A Multicenter Retrospective Cohort Study.

PURPOSE: To assess patient satisfaction and quality of life after refractive lens exchange with a trifocal intraocular lens (IOL). METHODS: Consecutive patients who underwent refractive lens exchange with the AT LISA tri or AT LISA tri toric IOL (Carl Zeiss Meditec AG) at one of five surgical centers were surveyed for their quality of life and satisfaction after surgery using a standardized questionnaire. Patient responses were compared to patient characteristics such as age, sex, axial lengths, and preoperative refraction. RESULTS: A total of 102 patients with 204 treated eyes were included in the analysis. The mean age was 54.6 ± 5.2 years. A total of 172 eyes were hypermetropic, 3 were emmetropic, and 25 were myopic, with a mean preoperative refractive error of 0.93 ± 2.17 diopters. Reported postoperative satisfaction was as follows: 81.4% stated that their expectations were completely met and 17.6% stated that they were partially met. Self-reported refractive error quality of life improved significantly in all queried areas of life. Most frequently reported postoperative limitations were driving at night and driving in bad weather conditions. Halos were reported by 91 (90.1%) patients. CONCLUSIONS: Patient satisfaction and self-reported quality of life after refractive lens exchange with the AT LISA tri or AT LISA tri toric IOL was high. Glare and halos remain the only significant drawback of the procedure, leading to 40% of patients experiencing difficulties in night driving. Preoperative communication of these drawbacks is obligatory to avoid postoperative disappointment. [J Refract Surg. 2021;37(11):768-774.].

Nighttime Symptoms After Monocular SMILE: A Contralateral Eye Study.

INTRODUCTION: To investigate nighttime symptoms in patients with myopic anisometropia after monocular small incision lenticule extraction (SMILE) surgery. METHODS: Thirty-six patients who had undergone monocular SMILE more than 6 months previously were recruited at the Eye & ENT Hospital of Fudan University. The average age at surgery was 25.4 ± 6.1 years. Preoperative spherical equivalent (SE) was -3.77 ± 1.56 D in SMILE-treated eyes and -0.08 ± 0.66 D in unoperated eyes. Main measurements included uncorrected and corrected distance visual acuity, manifest refraction, halo radius, contrast sensitivity, nighttime symptoms, and patient satisfaction. RESULTS: The mean follow-up time was 13.9 ± 3.4 months. The efficacy and safety indexes were 1.18 and 1.28, respectively. The halo radius was not significantly different between SMILE-treated and unoperated eyes under luminance conditions of 1, 5, and 100 cd/m2 (P = 0.055). No significant differences were observed in contrast sensitivity at all spatial frequencies between eyes under both uncorrected and corrected conditions (all P > 0.05). None of the patients reported moderate or severe symptoms at night. Mild symptoms (glare, halo, starburst) were reported and binocularly equal in 13 patients, whereas four patients reported better night vision in SMILE-treated eyes than unoperated eyes, and one of them experienced mild night vision disturbance. The overall satisfaction score was 9.39 ± 0.80. CONCLUSIONS: The disk halo size and contrast sensitivity in SMILE-treated eyes were similar to those in unoperated eyes, and nighttime symptoms almost completely resolved after SMILE.

Secondary DMEK following failed primary DMEK.

PURPOSE: To report the outcomes of secondary Descemet Membrane Endothelial Keratoplasty (DMEK) performed for failed primary DMEK. METHODS: The medical records of all patients undergoing secondary DMEK due to failure of primary DMEK were reviewed. Reasons for failure were sought and best-corrected visual acuity (BCVA), endothelial cell density (ECD) and complications of secondary DMEK were evaluated. RESULTS: A total of 10 cases undergoing secondary DMEK following failed primary DMEK were identified. Presumed reasons for failure included donor ECD ≤ 2300 cells/mm2 (n = 4), difficulty during graft preparation (n = 2), graft detachment (n = 2), acute angle closure due to retroiridal air dislocation (n = 1), inverse graft positioning (n = 1) and phacoemulsification (n = 1). Eyes with low visual potential were not excluded from the study group. We should note that one patient (case no7) had both low ECD and graft detachment as reasons for failure and as a result he is counted twice. Median BCVA (decimal fraction) increased from 0.1 (range, 0.01; 0.3) to 0.5 (0.05; 1.0) at one month and remained stable thereafter. A BCVA of 0.5 or higher was achieved in 7 cases at the final follow-up. Mean ECD fell from 2628 ± 284 cells/mm2 to 1391 ± 252cells/mm2 at 6 months (47% reduction) and 959 ± 225cells/mm2 at 24 months (64% reduction) (P ≤ 0.028). Complications included the incomplete removal of the primary graft and mild iris bleeding, decompensation of a preexisting primary open-angle glaucoma and retroiridal air dislocation. CONCLUSIONS: Apart from low donor ECD, surgical challenges, i.e., difficulty with graft preparation, inverse graft positioning, and retroiridal air dislocation, were main reasons for failure of primary DMEK. Secondary DMEK showed a good safety profile and reasonable visual outcomes.

The impact of vitrectomy on outcomes achieved with 0.19 mg fluocinolone acetonide implant in patients with diabetic macular edema.

BACKGROUND: There is a lack of consensus on the use of intravitreal corticosteroid therapies in patients with diabetic macular edema (DME) and prior vitrectomized eyes in clinical practice. METHODS: Retro-IDEAL was a 3-year retrospective, multicenter study in patients with chronic DME (i.e. DME that persists or recurs despite treatment) treated with ILUVIEN® (0.2 µg daily fluocinolone acetonide intravitreal implant), who had suboptimal outcomes with first-line vascular endothelial growth-factor inhibitors and other DME therapies. RESULTS: A total of 81 eyes (63 patients) were included of which 39 eyes had undergone prior vitrectomy (PV group) while 42 eyes had not undergone prior vitrectomy (NPV). Baseline characteristics were balanced; however, more patients had proliferative diabetic retinopathy in the PV group vs. the NPV group (21.62% vs 9.38%, respectively). Over 36 months, mean visual acuity (VA) increased in both groups with a tendency for more ETDRS letters being gained in the NPV group (+5.33) vs. the PV group (+2.42). By month 36, central retinal thickness was reduced to ⩽300 µm in two-thirds of the eyes in both groups and the mean change from baseline in intraocular pressure was similar in both groups (+0.50 mmHg -0.75 mmHg; NPV and PV group). CONCLUSIONS: These long-term data suggest that the 0.2 µg/day FAc implant is effective in both vitrectomized and non-vitrectomized patients, with a manageable safety profile, and improved VA and reduced supplemental therapies for patients with a suboptimal response to first-line DME therapies. Clinicians may consider utilizing the FAc implant earlier in the DME disease process.

Predictability of intraocular lens power calculation after small-incision lenticule extraction for myopia.

PURPOSE: To evaluate and compare the predictability of intraocular lens (IOL) power calculation after small-incision lenticule extraction (SMILE) for myopia and myopic astigmatism. SETTING: Department of Ophthalmology, Philipps University of Marburg, Marburg, Germany. DESIGN: Retrospective comparative case series. METHODS: Preoperative evaluation included optical biometry using IOLMaster 500 and corneal tomography using Pentacam HR. The corneal tomography measurements were repeated at 3 months postoperatively. The change of spherical equivalent due to SMILE was calculated by the manifest refraction at corneal plane (SMILE-Dif). A theoretical model, involving the virtual implantation of the same IOL before and after SMILE, was used, and the IOL power calculations were performed using ray tracing (OKULIX, version 9.06) and third- (Hoffer Q, Holladay 1, and SRK/T) and fourth-generation (Haigis-L and Haigis) formulas. The difference between the IOL-induced refractive error at corneal plane before and after SMILE (IOL-Dif) was compared with SMILE-Dif. The prediction error (PE) was calculated as the difference between SMILE-Dif-IOL-Dif. RESULTS: The study included 204 eyes that underwent SMILE. The PE with ray tracing was -0.06 ± 0.40 diopter (D); Haigis-L, -0.39 ± 0.62 D; Haigis, 0.70 ± 0.48 D; Hoffer Q, 0.84 ± 0.47 D; Holladay 1, 1.21 ± 0.51 D; and SRK/T, 1.46 ± 0.54 D. The PE with ray tracing was significantly smaller compared with that of all formulas (P ≤ .001). The PE variance with ray tracing was σ2 = 0.159, being significantly more homogenous compared with that of all formulas (P ≤ .011, F ≥ 6.549). Ray tracing resulted in an absolute PE of 0.5 D or lesser in 81.9% of the cases, followed by Haigis-L (53.4%), Haigis (35.3%), Hoffer Q (25.5%), Holladay 1 (6.4%), and SRK/T (2.9%) formulas. CONCLUSIONS: Ray tracing was the most accurate approach for IOL power calculation after myopic SMILE.