Scheimpflug-Based Corneal Biomechanical Analysis As A Predictor of Glaucoma in Eyes With High Myopia.

Purpose: To address if corneal biomechanical behavior has a predictive value for the presence of glaucomatous optical neuropathy in eyes with high myopia. Patients and Methods: This observational cross-sectional study included 209 eyes from 108 consecutive patients, divided into four groups: high myopia and primary open-angle glaucoma (POAG) - HMG, n = 53; high myopia without POAG - HMNG, n = 53; non-myopic with POAG - POAG, n = 50; non-myopic and non-POAG- NMNG, n = 53. Biomechanical assessment was made through a Scheimpflug-camera-based technology. Receiver operating characteristic curves were made for the discrimination between groups. Multivariable logistic regression models were performed to address the predictive value of corneal biomechanics for the presence of glaucoma. Results: Areas Under the Receiver Operating Characteristic (AUROCs) above 0.6 were found in 6 parameters applied to discriminate between HMG and HMNG and six parameters to discriminate between POAG and NMNG. The biomechanical models with the highest power of prediction for the presence of glaucoma included 5 parameters with an AUROC of 0.947 for eyes with high myopia and 6 parameters with an AUROC of 0.857 for non-myopic eyes. In the final model, including all eyes, and adjusted for the presence of high myopia, the highest power of prediction for the presence of glaucoma was achieved including eight biomechanical parameters, with an AUROC of 0.917. Conclusion: Corneal biomechanics demonstrated differences in eyes with glaucoma and mainly in myopic eyes. A biomechanical model based on multivariable logistic regression analysis and adjusted for high myopia was built, with an overall probability of 91.7% for the correct prediction of glaucomatous damage.

Real-World Experience With Brolucizumab 6 mg for Diabetic Macular Edema.

Background This study aimed to assess functional and anatomical outcomes after one month of treatment with a single intravitreal injection (IVI) of brolucizumab in patients with diabetic macular edema (DME). Methodology A retrospective study was conducted on eyes with DME who received a single IVI of brolucizumab. The study was designed to assess visual function and optical coherence tomography (OCT) biomarkers at baseline and one month following a single brolucizumab IVI. A sub-analysis was conducted between the following two groups: group 1 - treatment with brolucizumab due to burden, needle phobia, or non-compliance (responders to standard anti-vascular endothelial growth factor (VEGF) or naïve); and group 2 - non-responsive to previous therapies (standard anti-VEGF ± corticosteroids). The main outcome measures included best-corrected visual acuity (BCVA; Early Treatment of Diabetic Retinopathy Study (ETDRS) letters), central foveal thickness, and OCT biomarkers such as the presence of subretinal fluid, the number of hyperreflective dots, the disorganization of retinal inner layers, the disruption of outer plexiform layer, external limiting membrane and ellipsoid zone, the presence of cysts in the nuclear layers (outer (ONL) and inner (INL)), and the number of cysts in ONL versus those in the INL. Safety outcomes were assessed. Results A total of 59 eyes from 42 patients were included, of which 47 eyes were in group 1 and 12 eyes were in group 2. At one month, patients had an improvement of two ETDRS letters on BCVA (p = 0.020), lower central foveal thickness (p < 0.001), fewer hyperreflective dots (p = 0.016), less outer plexiform layer disruption (p = 0.004), less inner and outer nuclear layer cysts (p < 0.001 and p = 0.001, respectively) and better relationship between ONL and INL cysts (p = 0.022). Results were significant in the subgroup of patients with previous responsive DME. No adverse events were reported. Conclusions This study demonstrates the effectiveness and safety after one injection of brolucizumab 6 mg in the management of DME, especially in previously responsive DME patients.

Intraocular lens power calculation: angle κ and ocular biomechanics.

PURPOSE: To study the effect of ocular biomechanics on the prediction error of intraocular lens (IOL) power calculation. SETTING: Centro Hospitalar Universitário do Porto, Porto, Portugal. DESIGN: Prospective longitudinal study. METHODS: This study included 67 subjects. Before cataract surgery subjects underwent biometry with IOLMaster 700 and biomechanical analysis with Corvis Scheimpflug technology. The targeted spherical equivalent was calculated with SRK-T and Barrett Universal II. Associations between prediction error (PE), absolute prediction error (AE), and biometric and biomechanical parameters were performed with stepwise multivariate linear correlation analysis. RESULTS: Using the SRKT formula, there was association between PE and Corvis Biomechanical Index (CBI, B = -0.531, P = .011) and between AE and the horizontal offset between the center of the pupil and the visual axis (angle κ, B = -0.274, P = .007). Considering the Barret Universal II formula, PE was independently associated with anterior chamber depth ( B = -0.279, P = .021) and CBI ( B = -0.520, P = .013) and AE was associated with angle κ ( B = -0.370, P = .007). CONCLUSIONS: A large angle κ may reduce the predictability of IOL power calculation. Ocular biomechanics likely influence the refractive outcomes after IOL implantation. This study showed that eyes with softer corneal biomechanics had more myopic PE. This may relate to anteriorization of the effective lens position. Dynamic measurements may be the way to progress into future formulas.

Comparison of Light-Based Devices in the Treatment of Meibomian Gland Dysfunction.

PURPOSE: To compare different light-based devices, namely, intense pulsed light (IPL) and IPL with low-level light therapy (LLLT), in the treatment of meibomian gland dysfunction (MGD). METHODS: This was a prospective, observational study that included patients with MGD. Group 1 included 58 eyes treated with IPL (eye-light®, Espansione Marketing S.p.A., Bologna, Italy), followed by LLLT (my-mask®, Espansione Marketing S.p.A., Bologna, Italy); Group 2 included 60 eyes treated with IPL (E>Eye®, E-Swin, Houdan, France); and Group 3 included 58 eyes treated with IPL (Thermaeye Plus®, OptiMed, Sydney, Australia). The presence of symptoms (Ocular Surface Disease Index (OSDI)) and ocular surface changes were evaluated at baseline, three weeks, and six months after treatment. RESULTS: At week three, there was an improvement in the OSDI in all groups (p<0.001), without differences among them (p=0.339). The lipid layer thickness (LLT) increased in Groups 1 and 2 (p<0.001), with a similar variation (p=0.144). Patients with superior OSDI and lower LLT at baseline had the greatest improvement in the respective parameters (p<0.001). The basal tear flow increased in Group 1 (p=0.012). Corneal staining (CS) significantly decreased in Groups 2 (p<0.001) and 3 (p<0.001). At six months, compared to three weeks, there was further improvement in the OSDI (p<0.001) and the LLT (p=0.007), in Group 1, and an increase in the presence of CS in Group 3 (p=0.011). CONCLUSION: IPL treatment led to a sustained decrease in patients' symptoms, even after six months. Different IPL devices seem to have different beneficial effects. Adding LLLT to IPL appears to have an additional long-term beneficial effect as well as positive effects on the lacrimal gland.

Detection of subclinical microvascular changes in systemic lupus erythematous using optical coherence tomography angiography: A systematic review and meta-analysis.

Systemic lupus erythematosus (SLE) is a chronic, systemic, autoimmune connective tissue disease that affects several vascular territories. We sought to assess the role of optical coherence tomography angiography in detecting subclinical microvascular alterations in SLE patients. PubMed, Scopus, and Web of Science databases were systematically searched until January 21, 2023. Studies using optical coherence tomography angiography as a primary diagnostic method to evaluate the macular microvasculature of SLE patients versus healthy controls were included. Primary outcomes were macular vessel density and foveal zone parameters. A meta-analysis was performed using a random-effects model. Of 301 screened abstracts, 15 were found eligible, enrolling 1,246 eyes from 1,013 patients. SLE patients presented a reduction of macular vessel density at both plexuses in all zones (whole scan, fovea, parafovea, and perifovea), and of foveal density compared with healthy controls. No differences were found at foveal avascular zone parameters. SLE patients presented a reduction of macular vessel density without signs or symptoms of SLE ocular involvement. Optical coherence tomography angiography application for the assessment of subclinical microvascular changes needs to be elucidated with longitudinal studies.

Posterior Capsular Rupture during Cataract Surgery in Eyes Previously Treated with Intravitreal Injections.

INTRODUCTION: Intravitreal injections (IVIs) are currently the most common intraocular surgical procedure worldwide. Some studies have reported a higher risk of intraoperative complications, namely, posterior capsular rupture (PCR), during cataract surgery. The aim of this retrospective and observational study, conducted at Department of Ophthalmology, Centro Hospitalar Universitário do Porto, was to assess the risk of PCR during cataract surgery in eyes previously treated with IVIs with anti-vascular endothelial growth factor (anti-VEGF) and/or corticosteroids. METHODS: Eyes undergoing cataract surgery between June 2019 and May 2021 were included. Combined surgeries, such as glaucoma surgery and pars plana vitrectomy, were excluded. The occurrence of PCR during cataract surgery in treated and previously untreated eyes with IVI was analyzed. RESULTS: A total of 5,813 cataract surgeries were analyzed; 4.1% of the cases had previously undergone IVI. The PCR rate in cataract surgery was 1.8%: 6.7% in eyes previously treated with IVI and 1.6% without previous IVI (OR = 4.5, 95% CI: 2.6-7.7, p < 0.001). The combined therapy (anti-VEGF with corticosteroids) presents a higher risk compared to the two therapies alone as monotherapy (OR = 11.6, 95% CI: 4.7-28.5, p < 0.001), as well as treated eyes treated with ≥10 IVI (OR = 2.1, 95% CI: 0.8-6.1, p = 0.144) and a time interval between the last IVI and cataract surgery was ≤6 months (OR = 1.9, 95% CI: 0.6-6.1, p = 0.296). CONCLUSION: These results demonstrate that eyes that require IV treatment prior to cataract surgery are at increased risk of CPA during cataract surgery, and careful assessment of the characteristics of the cataract and posterior capsule is critical.

Photoscreening for amblyopia risk factors assessment in young children: A systematic review with meta-analysis.

PURPOSE: Amblyopia is a leading cause of preventable and treatable vision loss in the pediatric population. Instrument-based screening of amblyopia-risk factors is being widely adopted but the audit of its results is still lacking. We sought to review the existing evidence regarding the outcomes of photoscreening applied to children under the age of three years. METHODS: A three-database search (Pubmed, ISI Web of Science, and Scopus) was performed from inception to March 2021. A meta-analysis of proportions was conducted to summarize the referral rate, untestable rate and positive predictive value (PPV). RESULTS: Thirteen studies were selected among 705 original abstracts. The quantitative analysis included twelve studies enrolling 64,041 children. Of these, 13% (95%CI: 7-19%) were referred for further confirmation of the screening result. Astigmatism was the most common diagnosis both after screening and after ophthalmologic assessment of referred children. The pooled untestable rate and PPV were 8% (95%CI: 3-15%) and 56% (95%CI: 40-71%), respectively. CONCLUSION: There is no global consensus on the optimal age, frequency or what magnitude of refractive error must be considered an amblyopia-risk factor. Optimization of referral criteria is therefore warranted.

The Impact of Early Photoscreening on Medium-term Visual Acuity: A Population-Based Study.

PURPOSE: To analyze the outcomes of an early ophthalmological intervention in children included in the pilot project of the "Rastreio de Saúde Visual Infantil" (RSVI) visual screening program in Portugal. METHODS: This was a retrospective analysis of the medical records of all children included in the RSVI from April 1, 2016 to December 31, 2016, and who were referred to an ophthalmology appointment. Data of refractive errors, anisometropia, amblyopia, instituted treatments, and visual acuity at the end of the ophthalmological intervention were collected. RESULTS: Two hundred sixty-seven (18.2%) 2-year-old children from the Centro Hospitalar Universitário do Porto reference area had a positive screening result and were subsequently referred to an ophthalmology appointment. Glasses were prescribed to 31.1% of the patients who attended. Presumed amblyopia was diagnosed in 2.5% and occlusion was prescribed. At the end of a median follow-up of 3 years, of those who wore glasses without occlusion, 94.3% had a visual acuity of 20/25 or better in both eyes with an asymmetry of two lines or less between eyes. Of the 4 children who wore glasses with occlusion, 3 of them had a visual acuity of 20/25 or better in both eyes with an asymmetry of two lines or less between eyes. CONCLUSIONS: This study demonstrates the effectiveness of an early intervention in the prevention and treatment of amblyopia, because after a median follow-up of 3 years after treatment none of the referred children met criteria for amblyopia and 94.3% of the referred children who had an intervention had a normal visual acuity. [J Pediatr Ophthalmol Strabismus. 2023;60(3):178-183.].

Systemic and vitreous biomarkers - new insights in diabetic retinopathy.

PURPOSE: Diabetic retinopathy (DR) is a microvascular inflammatory and neurodegenerative disease. The purpose of this study was to analyze the relationship between DR severity and the levels of potential biomarkers in the serum and/or vitreous. METHODS: A prospective, consecutive, controlled, observational study was performed between June 2018 and January 2020. Blood and vitreous samples were collected on the day of vitrectomy in patients without diabetes and in patients with diabetes with epiretinal membrane, macular edema, and indication for vitrectomy. RESULTS: Transthyretin (TTR) was the only blood biomarker with levels statistically higher in patients with diabetes (p = 0.037). However, no correlation with DR severity was observed. Erythropoietin (EPO) was the only blood biomarker whose levels were associated with DR severity (p = 0.036). In vitreous samples, levels of EPO (p = 0.011), interleukin (IL)-6 (p < 0.001), IL-8 (p < 0.001), IL-17 (p = 0.022), monokine induced by interferon-γ (MIG) (p < 0.001), and interferon gamma-induced protein 10 (IP-10) (p = 0.005) were significantly higher in patients with diabetes. Additionally, in vitreous, IL-6, IL-8, MIG, and IPL-10 levels were also higher in more severe DR cases (p < 0.05). CONCLUSIONS: Among the studied biomarkers, vitreous IL-6, IL-8, MIG, and IP-10 were the ones whose levels had the strongest coherent relationship with DR severity prediction and, thus, have the best potential post-vitrectomy prognostic value.

Evaluation of Functional Vision and Eye-Related Quality of Life in Children with Strabismus.

Background: Understanding how strabismus impacts a child's quality of life, as well as their families, should be an important key to guide treatment, not only from the ophthalmological point of view but also regarding psychological and social aspects, which are fundamental for a healthy and harmonious development. Methods: A cross-sectional study was performed to evaluate the functional vision and eye-related quality of life (ER-QOL) in a population of children with strabismus submitted or not to corrective surgery, using the recently developed Pediatric Eye Questionnaire (PedEyeQ) and to compare with age and gender-matched visually normal children. The PedEyeQ was applied to non-operated children with strabismus (n = 18), operated children with strabismus (n = 24), and visually normal children (n = 21). This instrument is composed of 3 components (Child, Proxy, and Parent) and has different versions according to the child's age (0-4, 5-11, or 12-17 years-old versions). Clinical data such as age, type of strabismus, angle of deviation, amblyopia, occlusion treatment, and surgical outcome were also recorded. Results: All PedEyeQ domain scores were significantly lower in children with strabismus compared with visually normal children, except the Child "functional vision" domain. Children with strabismus with successful corrective surgery had significantly lower scores in many domains of the Child, Proxy, and Parent components, compared with visually normal children. Conclusion: This study showed that strabismus has an important impact on affected children and their families, as assessed by PedEyeQ. Interestingly, children with prior successful corrective strabismus surgery had worse PedEyeQ scores compared to visually normal children. Educational programs and psychosocial rehabilitation interventions should be implemented in children with strabismus and their families.

Refractive Surgery for Older Children and Adults with Accommodative Esotropia: A Systematic Review.

INTRODUCTION: Accommodative esotropia (AET) is characterized by an esodeviation of the eyes due to uncorrected hyperopia, deficient fusional divergence, or high accommodative convergence. Decreasing hyperopia would reduce accommodative convergence and strabismus. We sought to review the existing evidence regarding the outcomes of refractive surgery in patients with AET. METHODS: A four-database search (Pubmed, ISI Web of Science, Cochrane, and Scopus) was performed from inception to March 2021 using the following MeSH terms: ("Refractive Surgical Procedures" OR "Keratomileusis, Laser In Situ" OR "Photorefractive Keratectomy" OR "Lens Implantation, Intraocular") AND ("Esotropia" OR "Accommodative Esotropia" OR "Refractive Esotropia" OR "Accommodative Strabismus"). No meta-analysis was performed due to studies' heterogeneity. RESULTS: Twenty-eight studies including 22 case series enrolling 378 patients and 6 case reports enrolling 8 patients were selected among 185 original abstracts. In the case series, a total of 378 patients (726 eyes) were recruited with an age range of 8-52 years. All studies reported mean follow-up periods of at least 12 months. Photorefractive keratectomy was performed in 7 studies, laser-assisted in situ keratomileusis in 9 studies, laser-assisted sub-epithelial keratectomy was reported in 1 study, and 3 studies implanted intraocular lenses, including iris-fixated and collamer. Considering the adult patients with a preoperative corrected esodeviation ≤10 prism diopters (PD) (n = 129), all but 5 (3.9%) presented orthophoria or ≤10PD after refractive surgery. All children but 4 (4.5%) ended up with an esodeviation ≤10PD after surgery with those exceptions being in the range of 11-15PD. Six case reports were included in this review, comprising a total of 8 patients (16 eyes) with an age range of 7-34 years and a follow-up range of 4-48 months. Six case reports were included in this review, comprising a total of 8 patients (16 eyes) with an age range of 7-34 years and a follow-up range of 4-48 months. CONCLUSION: Evidence produced so far points out that refractive surgery may be an alternative for spectacle correction for adults with AET ≤10PD. There is not enough evidence to recommend its use for patients under 18 years of age. The safety and predictability of these procedures for this purpose remains unclear as the selection criteria used for these patients are much different than the usual indications and there are no studies with long-term follow-up.

Changes in Ganglion Cell Layer Thickness after Treatment with the 0.2 µg/day Fluocinolone Acetonide Implant in Vitrectomized and Nonvitrectomized Eyes with Diabetic Macular Edema.

INTRODUCTION: The objective of this study is to compare changes in ganglion cell layer (GCL) between vitrectomized and nonvitrectomized eyes with diabetic macular edema (DME) over a 2-year period following treatment with 0.2 µg/day fluocinolone acetonide (FAc) implant. METHODS: Eighteen vitrectomized (group 1) and 8 nonvitrectomized (group 2) eyes were included in this cohort study. Changes in central macula GCL thickness were measured using the Spectralis spectral domain-optical coherence tomography at baseline and 6, 12, and 24 months of follow-up. Other parameters analyzed included best-corrected visual acuity (BCVA), central foveal thickness (CFT), and intraocular pressure (IOP). RESULTS: Treatment with the FAc implant led to small reductions in mean global GCL thickness versus baseline and contrasts with the control group that was stable or slightly increased versus baseline. FAc therapy also led to improvements in mean BCVA and CFT that were observed at Month 6 and maintained to Month 24. For vitrectomized and nonvitrectomized eyes, no differences were observed between mean global GCL, BCVA, and CFT values during follow-up. Linear correlations revealed that in all groups mean BCVA at Month 24 positively correlated with mean GCL thickness at baseline and at Month 24. IOP remained stable throughout the 24 months. CONCLUSION: There was no evident retinal neurodegeneration in the 2-year period following treatment with FAc in both groups. GCL thickness may be a useful biomarker for assessing safety and effectiveness in patients with DME.

Corneal Biomechanics for Ocular Hypertension, Primary Open-Angle Glaucoma, and Amyloidotic Glaucoma: A Comparative Study by Corvis ST.

BACKGROUND: To evaluate biomechanical parameters of the cornea provided by Corvis ST in patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma and to compare with healthy controls. METHODS: This was a cross-sectional study of patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma that underwent Corvis ST imaging. Primary outcome was the comparison of corneal biomechanical parameters between study groups after adjusting for age, gender, Goldmann intraocular pressure (GAT-IOP), and prostaglandin analogues medication. Secondary outcome was the comparison of different IOP measurements in each group. RESULTS: One hundred and eighty-three eyes from 115 patients were included: 61 with primary open-angle glaucoma, 32 with amyloidotic glaucoma, 37 with ocular hypertension and 53 were healthy controls. Amyloidotic glaucoma group had smaller radius (p=0.025), lower deflection amplitude at highest concavity (p=0.019), and higher integrated radius (p=0.014) than controls. Ocular hypertension group had higher stiffness parameter at first applanation (p=0.043) than those with primary open-angle glaucoma, and higher stress-strain index (p=0.049) than those with amyloidotic glaucoma. Biomechanically corrected intraocular pressure was significantly lower than Goldmann intraocular pressure in group with primary open-angle glaucoma (p=0.005) and control group (p=0.013), and Goldmann intraocular pressure adjusted for pachymetry in group with primary open-angle glaucoma (p=0.01). CONCLUSION: Eyes with amyloidotic glaucoma have more deformable corneas, while eyes with ocular hypertension have less deformable corneas. These findings may be linked to the susceptibility to glaucomatous damage and progression. There were significant differences between Goldmann applanation tonometry and biomechanically corrected intraocular ocular pressure provided by Corvis ST.

Clinical/Demographic Functional Testing and Multimodal Imaging Differences between Genetically Solved and Unsolved Retinitis Pigmentosa.

INTRODUCTION: The purpose of this study was to compare clinical/demographic functional testing and multimodal imaging features between genetically solved and genetically unsolved nonsyndromic retinitis pigmentosa (nsRP) patients. METHODS: A cross-sectional study was conducted at an inherited retinal dystrophies reference center. Consecutive patients with nsRP and available genetic testing results performed between 2018 and 2020 were included. Genetic testing was clinically oriented, and variants were classified according to the American College of Medical Genetics and Genomics. Only class IV or V variants were considered disease-causing. Clinical/demographic, functional, and imaging features were compared between genetically unsolved (G1) and genetically solved (G2) patients. RESULTS: A total of 175 patients (146 families) were included: 68 patients (59 families) in G1 and 107 patients (87 families) in G2. First symptoms <25 years, consanguinity, evidence for a particular inheritance pattern, and the absence of indicators for phenocopies were significantly more prevalent in G2. No significant differences were observed on best-corrected visual acuity. The visual field index and mean central retinal layer thickness were significantly higher in G1. The frequency of atypical features on multimodal imaging did not differ between groups. CONCLUSION: Individual clinical/demographic functional testing and multimodal imaging features should be considered when counseling patients about the probability of identifying disease-causing variants.

Efficacy and safety of intravitreal and periocular injection of corticosteroids in noninfectious uveitis: a systematic review.

Uveitis is among the leading causes of visual loss in the working age population. In noninfectious uveitis, corticosteroids are the first line therapy. We sought to review systematically the evidence regarding the regional corticosteroid delivery modalities in the treatment of noninfectious uveitis. A 5-database search (Pubmed, ISI Web of Science, Cochrane, ClinicalTrials.gov, and Scopus) was performed from inception to February, 2021. Nineteen studies with a total of 1,935 eyes of 1,753 patients were selected from 8,922 abstracts retrieved by the initial search. The most frequently compared regimens were intravitreal triamcinolone acetonide injection and orbital floor triamcinolone acetonide injection (2 studies), intravitreal triamcinolone acetonide injection and posterior sub-Tenon triamcinolone acetonide injection (2 studies), and posterior sub-Tenon triamcinolone acetonide injection with the intravitreal dexamethasone implant (2 studies). Our results show that the intravitreal injection of corticosteroids is more effective, but is associated with more adverse events, than periocular injection. Some evidence supports the use of subconjunctival triamcinolone acetonide over intravitreal/periocular triamcinolone acetonide. Moreover, the overall results of 0.59 mg dosage of the intravitreal fluocinolone acetonide implant were superior to those from the 2.1 mg dose. The evidence, however, is not robust, and further studies with standardized outcomes are warranted.

Biometric Predictability in Combined Cataract Surgery and Ahmed Glaucoma Valve Implantation Depending on Tube Position.

PURPOSE: To compare the predictability of biometric results in patients undergoing cataract surgery combined with Ahmed glaucoma valve (AGV) implantation according to tube position. METHODS: A retrospective cohort study was performed in patients who underwent phacoemulsification surgery combined with AGV implantation with the tube in posterior (group PC) and anterior (group AC) chamber, between November 2012 and April 2020. The main outcome was the mean biometric prediction error, according to tube position, using different formulas. RESULTS: The study included 49 eyes of 36 patients, 23 eyes in group PC and 26 eyes in group AC. Gender (p=0.774), age (p=0.822), type of glaucoma (p=0.168), preoperative correct distance visual acuity (p=0.139), axial length (p=0.765), anterior chamber depth (p=0.351), keratometry (p=0.577) and intraocular lens power (p=0.608) were similar between groups. Only preoperative intraocular pressure was higher in group PC (p=0.005). The mean prediction errors using Haigis, SRK/T, Hoffer Q, Holladay 1, Barrett Universal II, Kane and Hill RBF formulas were all positive in group PC (hyperopic) and all negative (myopic) in group AC. In group PC, there was no significant difference in prediction error between these formulas (p>0.05). In group AC, the formula with the worst prediction error was Haigis (p=0.001), and the best was Barrett Universal II (p=0.043). CONCLUSION: The biometric predictability and expected final refraction in phacoemulsification surgery combined with AGV implantation are modified by the position of the tube.

Corneal Biomechanical Assessment with Ultra-High-Speed Scheimpflug Imaging During Non-Contact Tonometry: A Prospective Review.

BACKGROUND: In recent years, increasing interest has arisen in the application of data from corneal biomechanics in many areas of ophthalmology, particularly to assist in the detection of early corneal ectasia or ectasia susceptibility, to predict corneal response to surgical or therapeutic interventions and in glaucoma management. Technology has evolved and, recently, the Scheimpflug principle was associated with a non-contact air-puff tonometer, allowing a thorough analysis of corneal biomechanics and a biomechanically corrected intraocular pressure assessment, opening up new perspectives both in ophthalmology and in other medical areas. Data from corneal biomechanics assessment are being integrated in artificial intelligence models in order to increase its value in clinical practice. OBJECTIVE: To review the state of the art in the field of corneal biomechanics assessment with special emphasis to the technology based on ultra-high-speed Scheimpflug imaging during non-contact tonometry. SUMMARY: A meticulous literature review was performed until the present day. We used 136 published manuscripts as our references. Both information from healthy individuals and descriptions of possible associations with systemic diseases are described. Additionally, it exposed information regarding several fields of ocular pathology, from cornea and ocular surface through areas of refractive surgery and glaucoma until vascular and structural diseases of the chorioretinal unit.

The Role of Corneal Biomechanics in the Assessment of Ectasia Susceptibility Before Laser Vision Correction.

PURPOSE: To describe the tomographic and corneal biomechanical status of a sample of eyes excluded from LVC and to present the differences in biomechanical behavior in relation to cutoffs of clinical- and tomography-based screening methods used in clinical practice. PATIENTS AND METHODS: Observational cross-sectional study including 61 eyes from 32 consecutive patients who were excluded from LVC in our department. Clinical and demographic data were collected from the patients' clinical records. Tomographic data was assessed with a Scheimpflug camera (Pentacam, OCULUS®). Ablation depth (µm) and residual stromal bed (µm) were calculated by the WaveLight® EX500 laser system software (Alcon, EUA). The corneal biomechanical assessment was made through ultra-high speed Scheimpflug imaging during noncontact tonometry (Corvis ST, OCULUS®). Several ectasia risk scores were analyzed. RESULTS: Mean age was 31.0±6 years old and mean manifest spherical equivalent was -2.01 ± 2.3D. Belin-Ambrósio deviation index was the tomographic parameter with higher proportion of eyes within the ectasia high risk interval. In the biomechanical assessment, more than 95% of eyes met the criteria for ectasia susceptibility in four of the first generation and in two of the second generation parameters. In a cutoff based comparative analysis, eyes with Kmax ≥45.5 D, eyes with VCOMA <0 and eyes with ARTmax ≤350 presented significantly softer corneal biomechanical behavior. CONCLUSION: The majority of eyes excluded from LVC in the present study met the criteria for ectasia susceptibility in several biomechanical parameters, validating the clinical and tomographic based screening prior to LVC in our center. Differences found in the biomechanical assessment regarding cutoffs used in clinical practice highlight its differential role in characterizing risk profile of these patients. Tomography should not be overlooked and the integration of all data, including treatment-related parameters, can be the future of risk ectasia screening prior LVC.

OPTICAL COHERENCE TOMOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY PARAMETERS IN PATIENTS WITH PHACOMATOSIS.

PURPOSE: To compare the retinal vasculature characteristics between eyes of patients with and without phacomatosis. METHODS: Case-control observational study with retinal vasculature evaluation by optical coherence tomography and optical coherence tomography angiography of the macula and disk. RESULTS: The study included 80 eyes. Neurofibromatosis Type 1 patients presented with a higher central macular thickness (P = 0.007), a lower optical disk nervous fiber layer (P = 0.006), a lower perimeter, area, and circularity of the foveal avascular zone (P < 0.05), a higher vascular density of macular avascular layer (AMVD) (P = 0.004), and a lower papillary vascular density of superficial capillary plexus (SPVD) (P = 0.048). Patients with tuberous sclerosis presented with an increase in central macular thickness (P = 0.024) and in vascular densities (P < 0.05) [except for macular vascular density of deep capillary plexus (PMVD), AMVD, and SPVD]. Patients with Sturge-Weber syndrome showed a decrease in optical disk nervous fiber layer (P < 0.001), subfoveal choroid thickness (P = 0.011), macular vascular density of superficial capillary plexus (SMVD) (P = 0.036), and SPVD (P < 0.001). CONCLUSION: Phacomatosis patients showed statistically significant differences of retinal vasculature characteristics, compared to eyes without pathology. Further studies are needed to determine when and if these parameters change with the course of the disease and if they can be used as biomarkers for disease severity or progression.

Return of phacoemulsification after emergency status related to COVID-19: experience of a tertiary referral center.

PURPOSE: To present a protocol of priority criteria for phacoemulsification after the backlog due to severe acute respiratory syndrome coronavirus (SARS-CoV)-2 pandemic status. SETTING: Ophthalmology department of Centro Hospitalar e Universitário do Porto (CHUP), Oporto, Portugal. DESIGN: Cross-sectional, nonrandomized, retrospective study. METHODOLOGY: Data of all patients waiting for cataract surgery were analyzed at the beginning of May 2020, after 2 months without performing elective surgery. The waiting time since surgical inscription was considered an independent and overriding factor. In addition, higher priority was given to patients with white or brunescent cataracts and patients with low visual acuity: corrected distance visual acuity (CDVA) of 20/200 or less in binocular patients or CDVA of 20/63 or less in monocular patients. Criteria of medium priority included patients who remained with anisometropia and patients with glaucoma or low to moderate risk for chronic angle closure. Data of scheduled surgeries in the following months were then analyzed. RESULTS: A total of 717 patients were waiting for phacoemulsification. One hundred ninety-one patients (26.64%) were on the waiting list more than 4.5 months; the medium waiting time was 3.51 ± 1.57 months. According to both priority criteria and waiting time, 348 (48.6%) were categorized as priority cases. A total of 158 patients (22.0%) met the highest priority; 61 patients (8.5%) met the medium priority criteria. In 129 patients (18.0%), priority was considered based solely on higher waiting time. This algorithm allowed surgeons to operate on all priority cases within the first 3 months. CONCLUSIONS: The presented protocol showed to be effective, providing a timely surgical opportunity for priority cases.