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BACKGROUND: Evaluation of the number of enucleations and eviscerations performed in Germany and the orbital implants used. METHOD: Analysis of the quality reports of German ophthalmological clinics for the years 2012-2021 provided by the Federal Joint Committee (Gemeinsamer Bundesausschuss, GBA). RESULTS: Almost 10 times as many enucleations (8368) as eviscerations (975) are performed in Germany. After enucleation, alloplastic implants are used most frequently (44.6% alloplastic, no further specification, 30.0% alloplastic coated, no further specification; 14.1% microporous implants) and autologous dermis-fat grafts in 6.1% of the cases. CONCLUSION: In Germany, significantly more enucleations than eviscerations are performed. Alloplastic orbital implants are preferred for primary reconstruction following enucleation.
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AIM: To investigate a novel phacoemulsification system "EVA NEXUS" (D.O.R.C., Dutch Opthalmic Research Center) in comparison to the existing system "EVA" in clinical use. And to compare both phacoemulsification systems in terms of efficiency, safety and postoperative inflammatory activity. METHODS: In this study standardized cataract surgery was performed on both eyes of the study participant, using the "EVA system" (control group, n=20) on one eye and the "EVA NEXUS system" (intervention group, n=20) on the other eye. Only patients with cataract LOCS Grading 1-3 and no accompanying eye diseases were included in this study. A total of 20 patients were included in this study, with each treatment arm including 20 eyes. During surgery a 0.1 mL aqueous humor sample was collected 1min after phacoemulsification to measure the total prostaglanin E2 concentrations using an enzyme-linked immunosorbent assay. The endothelial cell count, visual and refractive outcomes, and anterior chamber flare were evaluated preoperatively, and 1d, 1wk, and 3mo postoperatively. RESULTS: There were no statistically significant differences between both groups regarding intraoperative safety parameters including effective phacoemulsification time (P=0.904), balanced saline solution flow (P=0.701) and total surgery time (P=0.565). Postoperative prostaglandin E2 levels, anterior chamber flare as well as endothelial cell loss tended to be lower in the NEXUS-Group, however not being statistically significant (P=0.718; 0.164; 0.486). Both systems provided similar clinical outcomes, regarding best corrected visual acuity and refractive parameters, showing no statistically significant differences between both groups. CONCLUSION: Both systems show a high level of safety and efficency with similar results in terms of safety parameters including postoperative inflammatory activity and endothelial cell loss as well as visual and refractive outcomes. Although statistically not significant, the EVA NEXUS system tends to cause less postoperative inflammation with lower prostaglandin E2 levels and lower anterior chamber flare values.
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Purpose: To evaluate optical-coherence-tomography (OCT)-morphological and clinical parameters three years after primary rhegmatogenous retinal detachment (RRD) repair surgery and the role of postoperative foveal bulge sign. Methods: Of the 32 initially enrolled patients with primary RRD 20 (14 fovea-on, 6 fovea-off) completed this prospective study. Preoperatively and 3 years after surgery best corrected visual acuity (BCVA) and OCT including macula status, central retinal thickness (CRT), central choroidal thickness (CCT), thickness of each single retinal layer, integrity of cone-interdigitation-zone (CIZ) and ellipsoid zone (EZ), and presence of foveal bulge were evaluated. Results: Preoperatively fovea-off RRD patients show significantly thinner CCT, inner nuclear layer (INL) and inner plexiform layer (IPL) compared to fovea-on RRD patients, whereas only IPL and INL were significantly thicker compared to the fellow eye. Three years after surgery this thickening recovered. Final BCVA did not differ statistically significantly between fovea-off and fovea-on patients, no difference in CIZ-integrity or presence of foveal bulge was observed. Presence of foveal bulge at 3 years showed significantly better final BCVA and was associated with intact preoperative CIZ-integrity and postoperative EZ- and CIZ-integrity. The preoperative fovea status showed no correlation to the postoperative presence of foveal bulge. Conclusion: Three years after RRD repair retinal layers show similar thickness. The presence of foveal bulge is associated with better final BCVA. Sufficient pre- and postoperative CIZ-integrity as well as postoperative CIZ-integrity seem to be strongly associated with the restoration of foveal bulge. No correlation was found with the preoperative macular status or BCVA.
We analyzed long-term optical-coherence-tomography changes after rhegmatogenous retinal detachment repair. Three years after rhegmatogenous retinal detachment repair retinal layers show similar thickness and visual acuity did not differ between fovea off and fovea on patients. The restoration of foveal bulge sign was the most important factor for good postoperative visual acuity. Integrity of specific retinal layers, such as the ellipsoid zone and cone-interdigitation-zone, seems to be strongly associated with the restoration of the foveal bulge.
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OBJECTIVES: To determine real-life quantitative changes in OCT biomarkers in a large set of treatment naive patients in a real-life setting undergoing anti-VEGF therapy. For this purpose, we devised a novel deep learning based semantic segmentation algorithm providing the first benchmark results for automatic segmentation of 11 OCT features including biomarkers for neovascular age-related macular degeneration (nAMD). METHODS: Training of a Deep U-net based semantic segmentation ensemble algorithm for state-of-the-art semantic segmentation performance which was used to analyze OCT features prior to, after 3 and 12 months of anti-VEGF therapy. RESULTS: High F1 scores of almost 1.0 for neurosensory retina and subretinal fluid on a separate hold-out test set with unseen patients. The algorithm performed worse for subretinal hyperreflective material and fibrovascular PED, on par with drusenoid PED, and better in segmenting fibrosis. In the evaluation of treatment naive OCT scans, significant changes occurred for intraretinal fluid (mean: 0.03 µm3 to 0.01 µm3, p < 0.001), subretinal fluid (0.08 µm3 to 0.01 µm3, p < 0.001), subretinal hyperreflective material (0.02 µm3 to 0.01 µm3, p < 0.001), fibrovascular PED (0.12 µm3 to 0.09 µm3, p = 0.02) and central retinal thickness C0 (225.78 µm3 to 169.40 µm3). The amounts of intraretinal fluid, fibrovascular PED, and ERM were predictive of poor outcome. CONCLUSIONS: The segmentation algorithm allows efficient volumetric analysis of OCT scans. Anti-VEGF provokes most potent changes in the first 3 months while a gradual loss of RPE hints at a progressing decline of visual acuity. Additional research is required to understand how these accurate OCT predictions can be leveraged for a personalized therapy regimen.
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Background/Objectives: To compare the epithelial thickness changes and the changes in epithelial wavefront aberrometry following spherical versus astigmatic myopic small incision lenticule extraction (SMILE). Methods: Eighty-six eyes of 86 patients who underwent SMILE were included in this retrospective study. A total of 43 eyes underwent myopic spherical correction (spherical group) and 43 eyes underwent myopic cylindrical correction (cylindrical group). The groups were matched according to the spherical equivalent of surgically corrected refraction. Subjective manifest refraction as well as high-resolution anterior segment optical coherence tomography (MS-39; CSO; Florence, Italy) were obtained preoperatively as well as 3 months postoperatively. The latter was utilized for computing epithelial wavefront aberrometry in addition to epithelial thickness mapping. Results: Epithelial thickness increased significantly in both groups after SMILE (p < 0.01). In the cylindrical group, epithelial thickening was more pronounced on the flat meridian compared to the steep meridian (p = 0.04). In both groups, epithelial wavefront aberrometry showed a significant postoperative increase in the epithelium's spherical refractive power, causing a myopization of -0.24 ± 0.42 diopters (D) in the spherical group (p < 0.01) and -0.41 ± 0.52 D in the cylindrical group (p < 0.0001). While no significant changes in epithelial cylindrical refractive power were observed in the spherical group, a significant increase was noted in the cylindrical group from -0.21 ± 0.24 D to -0.37 ± 0.31 D (p = 0.01). In both groups, epithelial higher-order aberrations increased significantly (p < 0.001). Conclusions: Postoperative epithelial remodeling after SMILE alters lower-order (sphere and cylinder) and higher-order aberrations of the corneal epithelial wavefront and might contribute to refractive undercorrection, especially in astigmatic corrections. Epithelial wavefront aberrometry can be used to quantify the refractive effect of epithelial remodeling processes after keratorefractive surgery.
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Purpose: Ectasia screening in candidates for laser refractive surgery is mandatory during preoperative evaluation. Despite the availability of modern imaging techniques, refractive surgeons often face borderline decisions when patients present with suspicious tomographic findings. This case series presents refractive candidates with suspicious tomographic findings and demonstrates how to interpret them using Scheimpflug imaging and additional anterior segment optical coherence tomography (AS-OCT). Setting: Department of Ophthalmology, University Hospital, LMU Munich. Case series: This case series examines six potential candidates for refractive surgery with a mean age of 29.2 ± 3.9 years, whose corneal assessments using Scheimpflug imaging raised suspicion for ectasia. Each candidate was additionally examined with AS-OCT and reevaluated. The mean manifest subjective spherical equivalent was -3.67 ± 1.8 diopters. The total corneal thickness measured 537 µm ± 30 µm at its thinnest point. None of the candidates had any reported underlying corneal or ophthalmic diseases, and slit lamp examinations revealed no abnormal morphological findings. Conclusions: Both Scheimpflug imaging and AS-OCT are appropriate tools for screening refractive candidates for ectasia. While topographic and elevation analyses yielded comparable results regarding corneal structure, the epithelial mapping provided by AS-OCT played a critical role in decision-making for cases with borderline tomographic findings. Establishing a global consensus on the use of epithelial mapping in ectasia screening is necessary.
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BACKGROUND: A lamellar macular hole (LMH) is characterized by a distinct morphologic configuration and can be distinguished from related entities such as macular pseudohole (MPH) and epiretinal membrane with foveoschisis (ERM-FS) by clear morphologic features. PURPOSE: Based on current knowledge, the pathophysiologic function of LMH in the spectrum of vitreomacular interface diseases will be described and therapeutic concepts will be presented. METHODS: Current studies are supplemented by case reports to provide a schematic overview of the natural history and therapeutic concepts at the vitreomacular interface. RESULTS: The LMH is as a retrospective marker for pathologic posterior vitreous detachment in adult patients and may be interpreted as the pathophysiologic center of tractional maculopathies. Various vitreomacular pathologies can result in LMH: a detached vitreomacular traction, a spontaneously closed penetrating macular hole, or an epiretinal membrane with foveoschisis. Pathophysiologically, a degenerative, progressive loss of the architecture of the foveal muller cell cone may be the underlaying mechanism, resulting in the typical undermining of the hole edges and occasionally in a full thickness macular hole. The optimal timing and the appropriate surgical method are the focus of current clinical studies. CONCLUSION: The pathophysiology of LMH indicates a smooth transition of tractive maculopathies. These should be prospectively evaluated in order to develop evidence-based treatment strategies for LMH.
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Perforaciones de la Retina , Humanos , Perforaciones de la Retina/fisiopatología , Perforaciones de la Retina/terapia , Perforaciones de la Retina/patología , Cuerpo Vítreo/patología , Cuerpo Vítreo/fisiopatología , Desprendimiento del Vítreo/fisiopatología , Desprendimiento del Vítreo/terapia , Desprendimiento del Vítreo/diagnósticoRESUMEN
An epiretinal membrane (ERM) is a frequently occurring disease affecting the macula, which can be associated with visual impairment and metamorphopsia, depending on the severity and location. A distinction is made between an idiopathic form caused by age-related changes of the vitreous body and a secondary form associated with diseases of the posterior segment. The development of fibrocellular epiretinal membranes formed by dedifferentiation of intraretinal and extraretinal cells at the level of the vitreomacular interface plays a major role in the pathogenesis. The diagnostics and indications for surgical treatment of ERM are based on the visual acuity, evidence of metamorphopsia, ophthalmoscopic findings and optical coherence tomography (OCT) of the macula. In addition to the possibility of observation of the course where benign spontaneous courses are not uncommon, pars plana vitrectomy (PPV) with peeling of the ERM and internal limiting membrane (ILM) to prevent recurrences is the treatment of choice in symptomatic patients. The prognosis after surgical treatment is very good. In approximately two thirds of the cases, an improvement in visual acuity and/or a reduction of metamorphopsia can be achieved, with a number of predictive, primarily OCT-based factors enabling a prediction of the functional prognosis. Comprehensive patient education regarding the generally long duration of postoperative rehabilitation and the possibility of persistent symptoms or visual deterioration despite successful membrane removal is essential.
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Membrana Epirretinal , Tomografía de Coherencia Óptica , Vitrectomía , Humanos , Membrana Epirretinal/cirugía , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/patología , Vitrectomía/métodos , Trastornos de la Visión/etiología , Trastornos de la Visión/cirugía , Trastornos de la Visión/diagnóstico , Agudeza Visual/fisiologíaRESUMEN
PURPOSE: Uveal melanoma (UM), although a rare malignancy, stands as the most prevalent intraocular malignancy in adults. Controversies persist regarding the dose dependency of local control (LC) through radiation therapy. This study sought to elucidate the significance of the prescription dose by employing time-dose-response models for patients with UM receiving photon-based stereotactic radiosurgery (SRS). METHODS AND MATERIALS: The analysis included patients with UM treated between 2005 and 2019. All patients underwent single-fraction SRS. Datapoints were separated into 3 dose groups, with Kaplan-Meier analysis performed on each group, from which time-dose-response models for LC were created at 2, 4, and 7 years after SRS using maximum-likelihood fitted logistic models. RESULTS: Outcomes from 594 patients with 594 UMs were used to create time-dose-response models. The prescribed doses and the number of patients were as follows: 17 to 19 Gy (24 patients), 20 Gy (122 patients), 21 Gy (442 patients), and 22 Gy (6 patients). Averaged over all patients and doses, LC rates at 2, 4, and 7 years were 94.4%, 88.2%, and 69.0%, respectively. Time-dose-response models for LC demonstrated a dose-dependent effect, showing 2-year LC rates of more than 90% with 20 Gy and 95% with 22 Gy. For 4 years and a LC of 90%, a dose of approximately 21 Gy was required. After 7 years, the 21 Gy prescription dose was predicted to maintain a LC above 70%, sharply declining to less than 60% LC with 19 Gy and less than 40% with 18 Gy. CONCLUSIONS: In contrast to prior findings, the time-dose-response models for UM undergoing photon-based SRS emphasize the critical role of the prescription dose in achieving lasting LC. The dose selection must be carefully balanced against toxicity risks, considering tumor geometry and individual patient characteristics to tailor treatments accordingly.
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Full-thickness macular holes (FTMH) usually result in a pronounced reduction of visual acuity and represent one of the most frequent indications for retinal surgery. If diagnosed and treatment is initiated at an early stage, surgery has a high success rate with respect to both hole closure and improvement of visual acuity. Optical coherence tomography (OCT)-based staging and sizing enables an estimation of the surgical outcome. The differential diagnostic distinction from clinically similar disorders, such as lamellar macular holes, macular pseudoholes, and foveoschisis is clinically relevant as the pathogenesis, prognosis and treatment are significantly different. While vitrectomy with peeling of the inner limiting membrane (ILM) and gas tamponade is established as the standard treatment for FTMH, some aspects of treatment are handled differently between surgeons, such as the timing of surgery, the choice of endotamponade and the type and duration of postoperative positioning. For FTMH associated with vitreomacular traction, alternative treatment options in addition to vitrectomy include intravitreal ocriplasmin injection and pneumatic vitreolysis. The current clinical guidelines of the German ophthalmological societies summarize the evidence-based recommendations for diagnosis and treatment of FTMH.
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Guías de Práctica Clínica como Asunto , Perforaciones de la Retina , Vitrectomía , Humanos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/terapia , Perforaciones de la Retina/cirugía , Vitrectomía/métodos , Diagnóstico Diferencial , Tomografía de Coherencia Óptica , Alemania , Endotaponamiento/métodosRESUMEN
Vitreomacular traction is a tractive foveolar adhesion of the posterior vitreous limiting membrane, resulting in pathological structural alterations of the vitreomacular interface. This must be differentiated from physiological vitreomacular adhesion, which exhibits a completely preserved foveolar depression. Symptoms depend on the severity of the macular changes and typically include reduced visual acuity, reading problems and metamorphopsia. High-resolution spectral domain optical coherence tomography (SDOCT) imaging enables classification of the sometimes only subtle morphological changes. If pronounced vitreomacular traction is accompanied by epiretinal gliosis and alterations to the outer retina, it is referred to as a vitreomacular traction syndrome. Vitreomacular traction has a high probability of spontaneous resolution within 12 months. Therefore, treatment should only be carried out in cases of undue suffering of the patient and with symptoms during bilateral vision and a lack of spontaneous resolution. In addition to pars plana vitrectomy, alternative treatment options, such as intravitreal injection of ocriplasmin and pneumatic vitreolysis are discussed for vitreomacular traction with an associated macular hole; however, ocriplasmin is no longer available in Germany. The best anatomical results in comparative investigations were achieved by vitrectomy. Pneumatic vitreolysis is controversially discussed due to the increased risk of retinal tears. In one of the current S1 guidelines of the German ophthalmological societies evidence-based recommendations for the diagnostics and treatment of vitreomacular traction are summarized.
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Guías de Práctica Clínica como Asunto , Tomografía de Coherencia Óptica , Humanos , Enfermedades de la Retina/terapia , Enfermedades de la Retina/diagnóstico , Vitrectomía/métodos , Desprendimiento del Vítreo/terapia , Desprendimiento del Vítreo/diagnóstico , Oftalmología/métodos , Cuerpo Vítreo/patología , Cuerpo Vítreo/diagnóstico por imagen , Alemania , Medicina Basada en la Evidencia , Adherencias Tisulares/diagnóstico , Adherencias Tisulares/terapiaRESUMEN
Aim of this study was to evaluate the efficacy of switching treatment to faricimab in neovascular age-related macular degeneration (nAMD) from other anti-VEGF agents. Fifty-eight eyes of fifty-one patients with nAMD and a full upload series of four faricimab injections were included. Demographic data, multimodal imaging and treatment parameters were recorded. The primary outcome measures were changes in central subfield thickness (CST) and subfoveal choroidal thickness (SFCT). A subgroup analysis was performed for eyes with prior ranibizumab (R) or aflibercept (A) treatment. Mean injection intervals before and after switching were comparable (33.8 ± 11.2 vs. 29.3 ± 2.6 days; p = 0.08). Mean CST of 361.4 ± 108.1 µm prior to switching decreased significantly to 318.3 ± 97.7 µm (p < 0.01) after the third faricimab injection, regardless of prior anti-VEGF treatment (p < 0.01). Although SFCT slightly improved for the whole cohort from 165.8 ± 76.8 µm to 161.0 ± 82,8 µm (p = 0.029), subgroup analysis did not confirm this positive effect (subgroup R: p = 0.604; subgroup A: p = 0.306). In patients with a suboptimal response to aflibercept or ranibizumab in nAMD, farcimab can improve CST and slightly improve or maintain SFCT. Further prospective randomized trials are warranted.
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Inhibidores de la Angiogénesis , Coroides , Ranibizumab , Receptores de Factores de Crecimiento Endotelial Vascular , Proteínas Recombinantes de Fusión , Humanos , Masculino , Femenino , Anciano , Ranibizumab/administración & dosificación , Ranibizumab/uso terapéutico , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/uso terapéutico , Coroides/efectos de los fármacos , Coroides/diagnóstico por imagen , Coroides/patología , Anciano de 80 o más Años , Resultado del Tratamiento , Inhibidores de la Angiogénesis/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Receptores de Factores de Crecimiento Endotelial Vascular/administración & dosificación , Retina/patología , Retina/efectos de los fármacos , Retina/diagnóstico por imagen , Inyecciones Intravítreas , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/patología , Tomografía de Coherencia Óptica , Agudeza Visual/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Sustitución de MedicamentosRESUMEN
Purpose: To compare different corneal keratometry readings (swept-source-OCT-assisted biometry and Scheimpflug imaging) with a novel software platform for calculation of toric intraocular lenses. Setting: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. Design: Retrospective, non-randomized, clinical trial. Methods: Twenty-three eyes undergoing toric intraocular lens implantation were included. Inclusion criteria were preoperative regular corneal astigmatism of at least 1.00 D, no previous refractive surgery, no ocular surface diseases and no maculopathies. Lens exchange was performed with CALLISTO eye (Zeiss). For each patient, the expected postoperative residual refraction was calculated depending on three different corneal parameters of two different devices: standard K-front (K) and total keratometry (TK) obtained by a swept-source-OCT-assisted biometry system (IOL Master 700, Zeiss) as well as total corneal refractive power (TCRP) obtained by a Scheimpflug device (Pentacam AXL, Oculus). Barrett's formula for toric intraocular lenses was used for all calculations within a novel software platform (EQ workplace, Zeiss FORUM®). Results were statistically compared with postoperative refraction calculated according to the Harris dioptric power matrix. Results: The standard K values (mean PE 0.02 D ± 0.45 D) and TK values (mean PE 0.09 D ± 0.43 D) of the IOL Master 700 reached similar results (p = 0.96). 78% of eyes in both K and TK groups achieved SE within ±0.5 D of attempted correction and all eyes (100%) were within ±1.0 D of attempted correction in both groups. By contrast, the prediction error in the IOL calculation using the TCRP of the Scheimpflug device was significantly greater (mean PE -0.56 D ± 0.49 D; p = 0.00 vs. standard K and p = 0.00 vs. TK) with adjusted refractive indices. Thirty-nine and Ninety-one percentage of eyes in the TCRP group achieved SE within ±0.5 D (p = 0.008 K vs. TCRP and p = 0.005 TK vs. TCRP) and ± 1.0 D (p = 0.14 vs. TCRP) of attempted correction, respectively. Conclusion: All three corneal parameters (standard K, TK, TCRP) performed well in calculating toric IOLs. The most accurate refractive outcomes in toric IOL implantation were achieved by IOL calculations based on swept-source-OCT-assisted biometry. The SS-OCT-based K-front and TK values achieve comparable results in the calculation of toric IOLs.
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BACKGROUND: Optical coherence tomography and electroretinography studies have revealed structural and functional retinal alterations in individuals with schizophrenia spectrum disorders (SSDs). However, it remains unclear which specific retinal layers are affected; how the retina, brain, and clinical symptomatology are connected; and how alterations of the visual system are related to genetic disease risk. METHODS: Optical coherence tomography, electroretinography, and brain magnetic resonance imaging were applied to comprehensively investigate the visual system in a cohort of 103 patients with SSDs and 130 healthy control individuals. The sparse partial least squares algorithm was used to identify multivariate associations between clinical disease phenotype and biological alterations of the visual system. The association of the revealed patterns with individual polygenic disease risk for schizophrenia was explored in a post hoc analysis. In addition, covariate-adjusted case-control comparisons were performed for each individual optical coherence tomography and electroretinography parameter. RESULTS: The sparse partial least squares analysis yielded a phenotype-eye-brain signature of SSDs in which greater disease severity, longer duration of illness, and impaired cognition were associated with electrophysiological alterations and microstructural thinning of most retinal layers. Higher individual loading onto this disease-relevant signature of the visual system was significantly associated with elevated polygenic risk for schizophrenia. In case-control comparisons, patients with SSDs had lower macular thickness, thinner retinal nerve fiber and inner plexiform layers, less negative a-wave amplitude, and lower b-wave amplitude. CONCLUSIONS: This study demonstrates multimodal microstructural and electrophysiological retinal alterations in individuals with SSDs that are associated with disease severity and individual polygenic burden.
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We report two patients who displayed evidence of localized ocular inflammation after CAR T-cell infusion. To manage the resulting severe visual impairment, systemic corticosteroids were administered to both patients. This treatment led to a reduction in local inflammation and restored vision in one of the patients.
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Purpose: To assess the IOL power calculation accuracy in post-SMILE eyes using ray tracing and a range of total keratometry based IOL calculation formulae. Observations: Ray tracing showed excellent predictability in IOL power calculation after SMILE and its accuracy was clinically comparable with the Barrett TK Universal II and Haigis TK formula. Conclusions and importance: Incorporating posterior corneal curvature measurements into IOL power calculation after SMILE seems prudent. The ray tracing method as well as selected TK-based formulae yielded excellent accuracy and should be favored in post-SMILE eyes.
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BACKGROUND: Good vision highly depends on the transparency of the cornea, which is the "windscreen" of the eye. In fact, corneal blindness due to transparency loss is the second most common cause of blindness worldwide, and corneal transplantation is the main cure. Importantly, the cornea is normally avascular but can secondarily be invaded by pathological (blood and lymphatic) vessels due to severe inflammation, and the survival prognosis of a corneal graft mainly depends on the preoperative vascular condition of the recipient's cornea. Whereas transplants placed into avascular recipient beds enjoy long-term survival rates of > 90%, survival rates significantly decrease in pathologically pre-vascularized, so-called high-risk recipients, which account for around 10% of all performed transplants in Germany and > 75% in lower and middle-income countries worldwide. METHODS: This parallel-grouped, open-randomized, multicenter, prospective controlled exploratory investigator-initiated trial (IIT) intends to improve graft survival by preconditioning pathologically vascularized recipient corneas by (lymph)angioregressive treatment before high-risk corneal transplantation. For this purpose, corneal crosslinking (CXL) will be used, which has been shown to potently regress corneal blood and lymphatic vessels. Prior to transplantation, patients will be randomized into 2 groups: (1) CXL (intervention) or (2) no pretreatment (control). CXL will be repeated once if insufficient reduction of corneal neovascularization should be observed. All patients (both groups) will then undergo corneal transplantation. In the intervention group, remaining blood vessels will be additionally regressed using fine needle diathermy (on the day of transplantation). Afterwards, the incidence of graft rejection episodes will be evaluated for 24 months (primary endpoint). Overall graft survival, as well as regression of corneal vessels and/or recurrence, among other factors, will be analyzed (secondary endpoints). DISCUSSION: Based on preclinical and early pilot clinical evidence, we want to test the novel concept of temporary (lymph)angioregressive pretreatment of high-risk eyes by CXL to promote subsequent corneal graft survival. So far, there is no evidence-based approach to reliably improve graft survival in the high-risk corneal transplantation setting available in clinical routine. If successful, this approach will be the first to promote graft survival in high-risk transplants. It will significantly improve vision and quality of life in patients suffering from corneal blindness. TRIAL REGISTRATION: ClinicalTrials.gov NCT05870566. Registered on 22 May 2023.