High-Tech Parameters for the Evaluation of Signs and Symptoms of Dry Eye Disease: Identification of Clinical Cut-Offs and Agreement with Low-Tech Tests.

INTRODUCTION: High-tech devices for the assessment of dry eye disease (DED) are increasingly available. However, the agreement between high- and low-tech parameters has been poorly explored to date. Trying to fill these gaps, we conducted a post hoc analysis on a recently published retrospective study on patients with DED receiving both low- and high-tech (Keratograph®) assessments, and treatment with different lubricating eyedrops. METHODS: Six clinical questions were defined by the authors, considering literature gaps and their clinical experience, namely: (1) are NIKBUT-i and T-BUT interchangeable parameters? (2) What was the correlation between low- and high-tech parameters in untreated and treated patients with DED? (3) What was the correlation between signs and symptoms at baseline and during/after treatment? (4) Which parameters were better associated with symptoms? And with symptoms change over time? (5) What was the performance of NIKBUT-i and T-BUT in detecting clinically relevant changes? (6) What was the clinical advantage of adding other high- and low-tech parameters, respectively, to NIKBUT-i and T-BUT? RESULTS: Low-tech measures were the best descriptors of the Ocular Surface Disease Index (OSDI) at baseline. In contrast, high-tech assessments demonstrate better performance in detecting changes over time. The distribution of NIKBUT-i data was more dispersed than TBUT both at baseline and follow-up. At a fixed specificity of 80%, the sensitivity in detecting clinically relevant ameliorations of symptoms was 42% for NIKBUT-i and 25% for T-BUT. A battery of high-tech tests could detect 90% of clinical amelioration, compared with 45% with low-tech tests (p < 0.001). Correlation between low- and high-tech parameters in both treated and untreated patients is lacking. CONCLUSIONS: Low-tech measures are adequate for diagnostic purposes in DED, whereas high-tech showed better performances at follow-up, particularly when different tests are combined. Overall, poor interchangeability among parameters and agreement with symptoms was reported both with high- and low-tech assessments.

Utilising Narrative Medicine to Identify Key Factors Affecting Quality of Life in Dry Eye Disease: An Italian Multicentre Study.

INTRODUCTION: Despite an improved understanding of its pathogenesis, dry eye disease (DED) remains relatively underestimated and its treatment challenging. A better alignment between the clinical evaluation and the patient self-assessment also requires capturing the whole patient experience of DED. This project aimed to unveil this experience through narrative medicine (NM). METHODS: The project involved 38 expert centres in Italy and one in San Marino, targeting adult patients with DED, their informal caregivers and their treating ophthalmologists. Written narratives and sociodemographic and quality of life (QoL)-related data were anonymously collected through the project's webpage. Narratives were analysed through MAXQDA (VERBI Software, Berlin, Germany), NM classifications and content analysis. RESULTS: A total of 171 patients with DED, 37 informal caregivers and 81 ophthalmologists participated in the research. DED was defined as a disabling condition by 19% of patients and 35% of caregivers; 70% of patients reported that a therapeutic alliance is an integral part of DED treatment and 32% hope for more effective therapies. Forty-four per cent of patients assessed their own QoL as good; however, DED emerged as importantly impacting work performance and social events. DED physical, emotional and economic burden and the cruciality of a trusting care relationship represent the main themes that emerged across all narratives, while empathy and effective treatment are among the factors favouring coping with DED. CONCLUSION: This project marked a pioneering initiative investigating the lived experience of patients with DED through NM, simultaneously involving all viewpoints involved in the care pathway. NM enabled the unveiling of factors favouring the ability to cope with DED and its associated QoL implications and provided valuable insights to improve the therapeutic alliance.

Seeing eye to eye: a modified Delphi method-based multidisciplinary expert consensus on the diagnosis and treatment of vernal keratoconjunctivitis.

Vernal keratoconjunctivitis (VKC) is a chronic, recurrent, inflammatory disease that affects both eyes, often with asymmetric severity, potentially causing major visual complications. The seasonal management of VKC can be challenging, especially when specialists with different diagnostic and therapeutic approaches need to be consulted. The aim of this expert panel was to reach a national consensus among pediatric allergologists and ophthalmologists on the diagnosis and treatment of VKC. This consensus was developed by an expert panel of 17 Italian pediatric allergologists and ophthalmologists with over a decade of experience. Ten statements on VKC diagnosis and treatment formulated after a thorough review of current literature were evaluated by the panelists. The level of agreement was quantitatively assessed using a 5-point Likert scale. Consensus was reached if ≥ 75.0% of panelists agreed to any given statement. The consensus emphasizes the importance of evaluation by multispecialty reference centers or experienced specialists for accurate diagnosis. Prompt diagnosis, especially during active phases, is crucial and should occur before corticosteroid therapy. The Bonini score from 2007 is the preferred tool for VKC assessment, although future revisions may be considered. Short cycles of topical corticosteroids should be preferred over prolonged use, even during immunomodulatory therapy. When cyclosporine fails, tacrolimus should be considered. CONCLUSION: This is the first consensus on the management of VKC that has gathered the expert opinions of both pediatricians and ophthalmologists. The outcome of this multidisciplinary effort provides a uniform approach to VKC diagnosis and treatment, thereby facilitating patient management across the country. WHAT IS KNOWN: • Vernal keratoconjunctivitis (VKC) is a chronic recurrent ocular disease particularly prevalent in the pediatric population. • Despite its relevance, there is a lack of standardized approaches shared between pediatricians and ophthalmologists, leading to notable variations in clinical practice. WHAT IS NEW: • This expert panel, comprising 17 pediatric allergologists and ophthalmologists, has reached a national consensus to provide standardized guidance for VKC management. • The consensus emphasizes the importance of a multidisciplinary approach to managing VKC, ensuring consistent and effective patient care.

Anterior chamber retained lens fragments: A novel approach with Nd:Yag laser.

METHODS: Multicenter retrospective case series of nd:Yag laser fragmentation of LF in twenty eyes at different clinics discovered after cataract surgery performed through phacoemulsification and implant of intraocular lens (IOL). CONCLUSION: Early nd:Yag laser procedure is a good option to use for retained lenticular fragments in the anterior chamber after cataract extraction, to reduce damages to the endothelium caused by the LF, to lower patient discomfort to re-enter surgery, to minimize costs of surgical re-intervention and to avoid possible inflammatory complications given by the retained fragments that may not be reabsorbed properly and may even present several years after primary surgery leading to damages to endothelium caused by the lenticular fragments and visual disturbances.

Estimation of pupil size at iris plane and its magnification after cataract surgery.

PURPOSE: To estimate the pupil size (at the iris plane) under photopic (PPH) and scotopic (PS) conditions after phacoemulsification with intraocular lens (IOL) implantation. METHODS: This retrospective observational cohort study included 190 virgin eyes from 190 patients who underwent cataract surgery with IOL implantation. Data collected with Aladdin (Topcon), AS-OCT MS-39 (CSO), and iTrace (Tracey) were SimK, mean pupillary power at 6 mm (MPP), anterior chamber depth (ACD), lens thickness (LT), axial length (AL), lens rise (LR), PPH and PS before and after surgery at 30 days, dysfunctional lens index, and opacity grade. The position of the postoperative iris plane (PIP) was measured manually with MS-39, and a multivariate regression formula was developed to predict it. Statistical analysis was performed using Statistical Package for Social Science (SPSS) (IBM). RESULTS: The mean and standard deviations were 42.61 ± 3.20 D for MMP at 6 mm, 3.35 ± 0.37 mm for ACD, 3.89 ± 0.18 mm for PIP (P < 0.01), 4.55 ± 0.42 mm for LT, 0.43 ± 0.24 mm for LR, and 25.91 ± 3.03 mm for AL. The mean preoperative and postoperative topographic pupil magnification was 12% and 14.22%, respectively (P < 0.01). Despite an increase in magnification, the postoperative pupil was smaller than the preoperative one both for scotopic and photopic conditions: The larger the preoperative pupil, the more it tends to reduce in the postoperative period. CONCLUSIONS: Analysis of the preoperative topographic pupil alone is not sufficient for a correct indication of the optical zone and total diameter of IOL to be implanted but must be correlated with biometric data. The topographic pupil, therefore, undergoes a change in magnification from the preoperative period to the postoperative period. Furthermore, the real pupil presents a modification and, in most cases, tends to be smaller postoperatively in both photopic and scotopic conditions.

Observational Clinical Investigation Evaluating an Ophthalmic Solution Containing Xanthan Gum and Low Concentration Desonide Phosphate in Dry Eye Disease Treatment.

INTRODUCTION: Patients with dry eye disease (DED) complain of a multitude of symptoms that affect their visual function and quality of life (QoL). This clinical investigation assessed the performance, tolerance, and safety of a novel preservative-free ophthalmic solution containing xanthan gum 0.2% and desonide sodium phosphate 0.025%. METHODS: This was an observational, prospective, multicentric, and post-market clinical investigation to assess the effect of three times a day instillation of the study formulation in patients suffering from DED. The primary objective was to achieve a 50% reduction in conjunctival hyperemia index as assessed with the OCULUS Keratograph after 1 month of treatment compared to baseline values. The secondary objectives included patient-reported outcomes, clinical performance, and safety. RESULTS: Thirty patients were enrolled (21 women, 9 men) with a mean age of 61.10 ± 14.53 years. The instillation of the study formulation was associated with a significant reduction in redness scores after 1 month of treatment compared to baseline (mean - 0.51 ± 0.51; p ≤ 0.0001). Although the primary endpoint was not completely met, a 50% reduction in the conjunctival hyperemia index was achieved in 23% of the participants, and 77% showed a reduction of 26% of the same index. In addition, the ophthalmic solution significantly increased tear film break-up time, and a significant reduction of corneal and conjunctival staining with fluorescein was achieved. It also reduced DED symptoms and had a very good safety profile. CONCLUSIONS: the study formulation produced a significant improvement in the signs, symptoms, and QoL of patients with mild to moderate DED with a good safety profile after 1 month of treatment.

Extensive Contact Lens Wear Modulates Expression of miRNA-320 and miRNA-423-5p in the Human Corneal Epithelium: Possible Biomarkers of Corneal Health and Environmental Impact.

The identification of new biomarkers of ocular diseases is nowadays of outmost importance both for early diagnosis and treatment. Epigenetics is a rapidly growing emerging area of research and its involvement in the pathophysiology of ocular disease and regulatory mechanisms is of undisputable importance for diagnostic purposes. Environmental changes may impact the ocular surface, and the knowledge of induced epigenetic changes might help to elucidate the mechanisms of ocular surface disorders. In this pilot study, we investigated the impact of extensive contact lens (CL) wearing on human corneal epithelium epigenetics. We performed ex vivo analysis of the expression of the miR-320 and miR-423-5p involved in the processes of cellular apoptosis and chronic inflammation. The human corneal epithelium was harvested from healthy patients before the photorefractive keratectomy (PRK). The patients were divided into two age- and sex-matched groups accordingly to CL wearing history with no CL wearers used as a control. The epithelium was stored frozen in dry ice at -80 °C and forwarded for miRNA extraction; afterwards, miRNA levels were detected using real-time PCR. Both miRNAs were highly expressed in CL wearers (p < 0.001), suggesting epigenetic modifications occurring in chronic ocular surface stress. These preliminary results show the relationships between selected miRNA expression and the chronic ocular surface stress associated with extensive CL use. MicroRNAs might be considered as biomarkers for the diagnosis of ocular surface conditions and the impact of environmental factors on ocular surface epigenetic. Furthermore, they might be considered as new therapeutic targets in ocular surface diseases.

One Soul and Several Faces of Evaporative Dry Eye Disease.

The ocular surface system interacts with, reacts with, and adapts to the daily continuous insults, trauma, and stimuli caused by direct exposure to the atmosphere and environment. Several tissue and para-inflammatory mechanisms interact to guarantee such an ultimate function, hence maintaining its healthy homeostatic equilibrium. Evaporation seriously affects the homeostasis of the system, thereby becoming a critical trigger in the pathogenesis of the vicious cycle of dry eye disease (DED). Tear film lipid composition, distribution, spreading, and efficiency are crucial factors in controlling water evaporation, and are involved in the onset of the hyperosmolar and inflammatory cascades of DED. The structure of tear film lipids, and subsequently the tear film, have a considerable impact on tears' properties and main functions, leading to a peculiar clinical picture and specific management.

The Use of Venous Catheter and Irrigation with Povidone-Iodine 0.6% in Patients with Punctal and Proximal Canalicular Stenosis: Preliminary Report.

Background: This study aimed to evaluate the safety and efficacy of povidone-iodine 0.6% (PVI) irrigation for preventing recurrence of stenosis after punctoplasty in patients with punctal and proximal canalicular stenosis treated using a venous catheter as a stent. Methods: Twenty patients were enrolled and divided into two groups. Group 1 received irrigation of 1 mL 0.6% PVI, while Group 2 received 1 mL of balanced salt solution (BSS). The patients underwent baseline, 15-, 30-, and 90-day assessments using the Ocular Surface Disease Index (OSDI) questionnaire, Symptoms Assessment in Dry Eye (SANDE), Schirmer I test, tear meniscus height (TMH), bulbar redness, meibography, and non-invasive breakup time (NIKBUT) through Keratograph 5M (Oculus, Germany). Results: At three months, both groups demonstrated statistically significant improvements in symptoms and ocular surface parameters. However, Group 1 showed statistically significant improvements in OSDI, SANDE scores, bulbar redness, and NIKBUT compared to Group 2. Additionally, no patients in Group 1 presented a recurrence of stenosis, while three patients in Group 2 demonstrated stenosis relapse at the end of the follow-up period. Conclusions: The application of a venous catheter and PVI 0.6% irrigations proved to be effective in treating proximal lacrimal duct stenosis, reducing the risk of recurrence and improving tear film stability, ocular discomfort symptoms, and ocular surface parameters.

How gut microbiota may impact ocular surface homeostasis and related disorders.

Changes in the bacterial flora in the gut, also described as gut microbiota, are readily acknowledged to be associated with several systemic diseases, especially those with an inflammatory, neuronal, psychological or hormonal factor involved in the pathogenesis and/or the perception of the disease. Maintaining ocular surface homeostasis is also based on all these four factors, and there is accumulating evidence in the literature on the relationship between gut microbiota and ocular surface diseases. The mechanisms involved are mostly interconnected due to the interaction of central and peripheral neuronal networks, inflammatory effectors and the hormonal system. A better understanding of the influence of the gut microbiota on the maintenance of ocular surface homeostasis, and on the onset or persistence of ocular surface disorders could bring new insights and help elucidate the epidemiology and pathology of ocular surface dynamics in health and disease. Revealing the exact nature of these associations could be of paramount importance for developing a holistic approach using highly promising new therapeutic strategies targeting ocular surface diseases.

Real-world experience with fluocinolone acetonide intravitreal implant in patients with diabetic macular edema.

OBJECTIVES: to evaluate long-term effectiveness and safety of fluocinolone acetonide (FAc) implant used as second-line treatment in patients with persistent diabetic macular edema (DME). METHODS: retrospective data chart review of 241 pseudophakic eyes of 178 patients treated with FAc from July 2017 to December 2021 in 10 medical retinal units in Italy. The primary endpoint was the change of best-corrected visual acuity (BCVA) and central macular thickness (CMT) at 2 years. A Student's paired t-test was used. Additional therapies for DME and intraocular pressure (IOP)-related events were also evaluated. RESULTS: efficacy of FAc was assessed in a subset of 111 eyes with at least 24 months of follow-up. Mean BCVA increased at 2 years by 5.1 ETDRS letters (95%CI = 2.6-7.5; p < 0.001) while mean CMT decreased by 189 µm (95% CI 151-227; p < 0.001). Thirty-eight of these eyes (34.2%) needed additional intravitreal treatments, mainly anti-VEGF. Safety was evaluated on the entire cohort of 241 eyes treated with FAc. Overall, 66 eyes (27.4%) required emergent IOP-lowering medications (typically within the first-year post FAc) while 14 eyes (5.8%) underwent trabeculectomy, mostly during the second year of follow-up. CONCLUSION: FAc implant provides a substantial long-term functional and anatomical benefit when used as second-line treatment in eyes with DME. IOP rise can be adequately managed with topical agents although some eyes may require IOP-lowering surgery.

Clinical and optical coherence tomography biomarkers as prognostic factors in dexamethasone intravitreal implant for diabetic macular edema.

PURPOSE: Aim of the study was to evaluate the efficacy of dexamethasone (DEX) 0.7 mg intravitreal implant in patients with diabetic macular edema (DME) and serous retinal detachment (SRD), and to study the prognostic factors on a follow up of 12 months. METHODS: Forty eyes of twenty- six patients with centre involving DME and SRD, who underwent DEX implant, were enrolled. Best-corrected visual acuity (BCVA), Swept source OCT imaging and intraocular pressure were evaluated. Central macular thickness (CMT), vitreomacular adhesion (VMA), disorganization of retinal inner layers (DRILs), hyperreflective dots (HRD), SRD and ellipsoid zone (EZ) disruption were included in the analysis at baseline and 12 months after implant. RESULTS: According to our parametric analysis, at 12 months, BVCA improvement from 48.6 ± 23.4 letters to 53.3 ± 24.5 letters was statistically significant (p = 0.04), CMT decreased from 460 ± 99.52 µm to 322.9 ± 117 µm. The presence at baseline of VMA (p = 0.01), EZ disruption (p = 0.03) and DRILs (p = 0.04), were associated with poor BCVA improvement at the end of follow-up. CONCLUSION: In conclusion, OCT biomarkers can be considered significant prognostic factors for treatment outcome in patients with DME undergoing DEX intravitreal implant.

Review of clinical outcomes of a cationic emulsion tear substitute in patients with dry eye disease.

First-line options for the treatment of dry eye disease (DED) rely on artificial tears (ATs), among which cationic emulsion (CE)-based ATs have been developed in order to mimic the healthy tear film for an improved restoration of the ocular surface homeostasis. In this review, we describe the outcomes reported in several studies, assessing the mode of action, ocular tolerance and clinical performance of a CE-based AT. Pilot studies have revealed that CE-based ATs can increase the volume and stability of the tear film while limiting its evaporation rate. Larger studies have demonstrated that CE-based ATs play a significant role in the improvement of both objective and subjective DED parameters, including superior efficacy on DED symptoms compared to several other available AT formulation types. Concomitantly, CE-based ATs have been shown to help patients to prevent or recover from corneal defects associated with refractive surgery. These positive outcomes on ocular surface epithelia are likely due to the combination of unique rheological behaviour and intrinsic anti-inflammatory properties. Based on all clinical findings, CE-based ATs represent a valuable treatment option for patients with various etiologies of DED including evaporative forms and would deserve evaluation of benefits in other surgical intervention types triggering DED.

Effectiveness of a New Active Tear Substitute Containing 0.2% Hyaluronic Acid and 0.001% Hydrocortisone on Signs and Symptoms of Dry Eye Disease by Means of Low- and High-Tech Assessments.

INTRODUCTION: An innovative eye drops formulation containing 0.2% hyaluronic acid and a low concentration of hydrocortisone (0.001%; hereafter HALH) has been recently placed on the market (Idroflog®, Alfa Intes, Italy) to manage the dysregulated parainflammation in patients with dry eye disease (DED). In the present paper, the effectiveness of HALH on the signs and symptoms of DED was retrospectively evaluated and compared with that one obtained using standard tear substitutes (STS) by means of low- and high-tech (Keratograph®) assessments. METHODS: This was a multicenter retrospective study carried out between February and April 2023, involving adult patients with DED diagnosis owing to post-cataract surgery, meibomian gland dysfunction, allergy, or glaucoma medications. The primary aim was to compare the changes induced by different therapies on Keratograph® parameters (noninvasive Keratograph tear breakup time [NIKBUT], tear meniscus height [TMH], eyelid meibography, conjunctival hyperemia, and conjunctivochalasis) or collected by traditional low-tech measures (tear breakup time [TBUT], Schirmer test, Efron score, and epithelial alterations) and the Ocular Surface Disease Index score. RESULTS: Data from 155 patients were analyzed. The effectiveness of HALH and STS was reported by both high- and low-tech measures. NIKBUT-first showed a significant improvement in the HALH group versus the STS one at 15 days (6.4 ± 3.6 vs 5.4 ± 3.7 s, p = 0.02), whereas this difference was latent with low-tech TBUT until 45 days (6.8 ± 2.6 vs 5.6 ± 2.3 s, p = 0.03). Patients with DED occurring after cataract surgery reported an enhanced activity of HALH versus STS, particularly for NIKBUT-first, TMH, Schirmer test, and hyperemia stage. CONCLUSION: These findings highlighted the effectiveness of HALH in all DED subtypes, especially in patients with post-cataract surgery, as well as its superiority versus STS in terms of tear film stability improvement. We recommend longer observation (i.e., 3-6 months) to fully ascertain whether the early improvement detected by high-tech measures will be confirmed in subsequent time points even using low-tech tests.

Clinical Results of Accelerated Iontophoresis-Assisted Epithelium-on Corneal Cross-linking for Progressive Keratoconus in Children.

PURPOSE: To evaluate the clinical characteristics of pediatric patients with progression of keratoconus after accelerated iontophoresis-assisted epithelium-on corneal cross-linking (I-ON CXL) and to assess the efficacy and safety of re-treatment using accelerated epithelium-off CXL (epi-OFF CXL). METHODS: Sixteen eyes of 16 patients (mean age: 14.6 ± 2.5 years) with keratoconus underwent I-ON CXL. The main outcome measures were uncorrected distance visual acuity, corrected distance visual acuity, maximum keratometry index (Kmax), minimum corneal thickness, elevation front and elevation back measured at the thinnest point, total higher order aberrations root main square (HOA RMS), coma RMS, and spherical aberration. An increment of Kmax greater than 1.00 diopter (D) and a decrease of greater than 20 µm in pachymetry were considered to determine the progression of keratoconus. Patients with progression of keratoconus after I-ON CXL were re-treated using an epi-OFF CXL protocol. RESULTS: Two years after I-ON CXL, 12 patients showed progression of keratoconus, whereas 4 patients were stable. There was significant worsening of Kmax (P = .04) and steepest keratometric reading (P = .01). Furthermore, a significant correlation was documented between progression of keratoconus and age (P = .02). These patients were re-treated using an epi-OFF protocol and after 2 years all patients were stable, and a statistically significant reduction of the mean Kmax (P = .007), HOA RMS (P = .05), and coma RMS (P = 05) was observed. CONCLUSIONS: I-ON CXL was ineffective in the treatment of pediatric keratoconus in younger children, whereas it had an efficacy of 2 years in older children. Re-treatment using epi-OFF CXL proved effective to halt progression of keratoconus after I-ON CXL failure. [J Pediatr Ophthalmol Strabismus. 2024;61(1):44-50.].

Antimicrobials and antiseptics: Lowering effect on ocular surface bacterial flora - A systematic review.

Topical antimicrobials and antiseptics are used perioperatively to reduce the ocular surface bacteria flora (OSBF) that are involved in the development of post-operative infectious complications. However, their effectiveness is still a controversial topic. This systematic review, performed according to the PRISMA guidelines and registered in PROSPERO, aims to provide an overview of the efficacy of the agents currently used in peri-cataract surgery and -intravitreal injections (IVI) in lowering the OSBF. Although effective in lowering OSBF, perioperative topical antimicrobials are associated with the risk of resistance development, with no obvious additional benefit compared with topical antisepsis. Conversely, the effectiveness of topical antiseptics before cataract surgery and IVI is strongly supported. Based on the available evidence, perioperative antimicrobials are not recommended, whereas the perioperative use of antiseptics is strongly recommended as prophylactic treatment for lowering the infection due to OSBF. Post-operative antimicrobials may be considered in eyes at higher risk for infection.

Prediction of total corneal power in keratoconus using anterior surface data.

CLINICAL RELEVANCE: Keratoconus results in an increase in anterior and posterior curvatures and a reduction in corneal thickness. Anterior corneal ectasia is partially compensated by remodelling the corneal epithelium. Therefore, there is an alteration in the relationship between corneal surfaces and variation in corneal power. The variation in corneal power is one of the sources that induces errors in IOL power calculation. BACKGROUND: This study aimed to assess a method for predicting total corneal power in keratoconus using several anterior surface parameters at 3 mm and 4 mm. METHODS: Tomographic data obtained using Pentacam (Oculus, Germany) were analysed from 280 eyes of 140 patients with keratoconus using anterior and posterior keratometry, anterior Q-value at 8 mm, central corneal thickness, Kmax location and value, and true net power at 4 mm (TNP). Calculated total corneal power (TCPc) at 3 mm was obtained using the Gauss formula. Predicted total corneal power at 3 mm (TCPp3) and 4 mm (TCPp4) was obtained from univariate (TCPp3u and TCPp4u) and multivariate linear regression formulae (TCPp3m and TCPp4m). SimK, anterior Q-value, vertical location, and Kmax value were used in the multivariate formulae. Mean absolute error (MAE) and median absolute error (MedAE) were also calculated. Absolute frequencies within dioptric ranges of all formulas divided for keratoconus grading were evaluated. RESULTS: TCPc and TNP exhibited a good correlation (R2 = 0.58, p < 0.05) with a higher dispersion above 50 D of corneal power. Highly significant correlations were observed between TCPp3u and TCPc (R2 = 0.978, p < 0.05) and TCPp3m and TCPc (R2 = 0.989, p < 0.05). Lower but significant correlations were observed between TCPp4u and TNP (R2 = 0.692, p < 0.05) and between TCPp4m and TNP (R2 = 0.887, p < 0.05). The best results for TCP prediction at 3 and 4 mm were obtained with TCPp3m and TCPp4m as follows: MAE of TCPp3m was 0.24 ± 0.20 (SD) D with MedAE of 0.20 D, while MAE of TCPp4m was 0.96 ± 0.77 D with MedAE of 0.80 D. The 3 mm multivariate regression formula results in higher absolute frequencies of prediction errors in the total eyes within 0.5 D (93%) than the univariate formula (81%). At 4mm, the multivariate regression formula has a lower percentage within 0.5 D (32%) than the univariate formula (41%), but the percentage of the multivariate formula is higher within 1 D (63%) than the univariate formula (56%). CONCLUSION: All formulas show a decrease in accuracy with increasing grades of keratoconus. Multivariate linear regression formulae using only anterior surface data can predict TCP with good approximation in eyes with keratoconus in cases where posterior surface parameters are unavailable. The vertical location of Kmax and the anterior asphericity could play a relevant role in the prediction of total corneal power in keratoconus.

Dry eye in mind: Exploring the relationship between sleep and ocular surface diseases.

PURPOSE: Dry Eye Disease (DED) is regarded as the most common ocular surface disease worldwide, entailing symptoms that have a major impact on the physical and psychological well-being of DED patients. In this context, the impact of sleep quality on DED has recently attracted attention. Indeed, although little is known about the mechanisms underlying the relationship between sleep and ocular surface diseases, recent evidence suggests that a reciprocal relationship exists between sleep quality and DED. Aim of the study was to investigate such relationship by means of both survey-based and instrumental analysis in a large population. PATIENTS AND METHODS: The present cross-sectional study included 1182 DED patients who completed the Insomnia Severity Index (ISI) and the Ocular Surface Disease Index (OSDI) questionnaires. Moreover, tear break-up time (TBUT) and ocular surface staining (OSS) data of included patients were collected by physicians. RESULTS: According to the findings of this study, in DED patients, the severity of dry eye symptoms and signs, assessed by OSDI score, TBUT, and ocular surface staining, is associated with more severe insomnia symptoms. Furthermore, higher severity of DED symptoms seems to be associated with the occurrence of nocturnal awakenings rather than with problems in falling asleep. CONCLUSIONS: Present work contributes to the understanding of the complex relationship between DED and insomnia by showing that in a large population of DED patients, the more severe the insomnia, the more severe the DED symptoms and signs.

Comparison between IOL MASTER 500 and MYAH with vector analysis in low and mild anterior corneal astigmatism.

PURPOSE: Evaluate the agreement between IOL Master 500 (Carl Zeiss Meditec AG, Germany) and MYAH (Topcon EU, Visia Imaging, Japan) in measuring axial length, keratometry, and anterior corneal astigmatism. SETTING: Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Ophthalmology Clinic, University of Messina, Messina, Italy. METHODS: In this prospective study, 40 eyes (right eye 25, left eye 15) of 40 patients were included. Axial length (AL), keratometry (K1, K2), and anterior corneal astigmatism (ACA) were measured. AL, mean K (Kavg) and magnitude of ACA were compared using Bland - Altman plot analysis, parametric and nonparametric statistical analysis. The difference vector and angle of error of the ACA measured by the two devices were evaluated by vector analysis using polar diagrams. RESULTS: Mean and standard deviation with IOL Master and with MYAH device was for AL 24.25 ± 1.22 mm and 24.25 ± 1.22 mm (p = .99), for Kavg 42.75 ± 1.53 D and 42.85 ± 1.52 D (p = .78), for Magnitude of ACA 1.00 ± 0.58 D and 0.89 ± 0.56 D (p = .38) respectively. High correlations were found for AL (R² = 0.999), Kavg (R² = 0.996), and ACA Magnitude (R² = 0.889). Bland-Altman analysis of the two devices found high agreement and absence of proportional bias (MYAH-IOL MASTER) were found between the two assessments for AL (bias = -0.0005 mm, p = .93), Kavg (bias = 0.0955 D, p = .76) and ACA (bias = 0.11 D, p = .41). Limit of agreement (upper/lower LoA, 95%CI) were respectively +0.057/-0.058 mm for AL, + 0.29/-0.09 D for Kavg and +0.49/-0.27 D for ACA. No statistical difference was found between the x-component and y-component of the ACA vector (p > .01), the difference vector (IOL MASTER-MYAH) was +0.14 D axis 159 with an absolute mean angle of error of 7.2 ± 7.5 degree. CONCLUSIONS: The instruments appear to be interchangeable for measurements of AL, keratometry, and magnitude of ACA with high agreement between the two devices. Also, in the presence of low astigmatism, the two instruments give the same results in terms of ACA.