Safety of intravitreal chemotherapy in the management of retinoblastoma: A systematic review of the literature.

Intravitreal chemotherapy is used as a salvage therapy for retinoblastoma with persistent or recurrent vitreous seeding after primary treatment. To assess the safety of this technique, we conducted a systematic review of all studies reporting ocular toxicity data. Forty-eight trials involving 2751 eyes were included. The most common complications were cataract, retinal toxicity, and vitreous hemorrhage. However, severe and permanent adverse events were limited, while the risk of extraocular dissemination, a significant concern, was practically eliminated through preventive techniques. Globe salvage rates ranged from 29 % to 100 %. In conclusion, intravitreal chemotherapy seems to improve prognosis of eyes with advanced disease, with an acceptable safety profile. Nevertheless, most relevant studies are retrospective, and no randomized trials have been performed. Recognizing the challenges regarding the conduct of randomized studies for such a rare pediatric cancer, we believe that multicenter trials through international collaborations can significantly enhance the available information.

Exploring vismodegib: A non-surgical breakthrough in the management of advanced periocular basal cell carcinoma.

The management of periocular basal cell carcinoma (BCC) is challenging due to its proximity to the eyeball. Vismodegib, a Hedgehog pathway inhibitor, has emerged as a therapeutic option for locally advanced and metastatic BCC. To critically appraise the relevant evidence, we conducted a systematic review of observational and experimental studies assessing the efficacy and safety of vismodegib for periocular BCC. Thirty-seven trials, including 435 patients, were eligible. No randomized trials were retrieved. Complete and overall clinical response rates were 20-88 % and 68-100 %, respectively. Disease progression was observed at a maximum rate of 14 %. Recurrence rates varied between 0 % and 31 %. The most common side effects were muscle cramps, dysgeusia, weight loss and alopecia. Treatment with vismodegib improved health-related quality of life. In conclusion, vismodegib represents an important novel treatment for advanced periocular BCC, with good response rates and acceptable tolerability profile. Nevertheless, its full potential needs clarification through randomized controlled trials.

DMEK surgical training: An instructional guide on various wet-lab methods.

Descemet membrane endothelial keratoplasty (DMEK) is a partial-thickness corneal transplantation procedure that involves selective transplantation of the Descemet membrane and endothelium. DMEK offers significant advantages over other keratoplasty techniques, such as faster visual rehabilitation, better final visual acuity due to minimal optical interface effects, lower risk of allograft rejection, and less long-term dependence on topical steroids. Despite all its advantages, DMEK has been found to be more challenging than other corneal transplantation techniques, and its steep learning curve appears to be an obstacle to its widespread use and adoption by corneal surgeons worldwide. DMEK surgical training laboratories (wet labs) provide a window of opportunity for surgeons to learn, prepare, manipulate, and deliver these grafts in a risk-free environment. Wet labs are a significant learning tool, especially for those institutions that have limited tissue availability in their local centers. We provide a step-by-step guide for preparing DMEK grafts using different techniques on human and nonhuman models with instructional videos. This article should eventually help the trainees and the educators understand the requirements for performing DMEK and conducting a DMEK wet lab and develop their skills and interests from a wide variety of available techniques.

Safety and Efficacy of Prostaglandin Analogues in the Immediate Postoperative Period after Uneventful Phacoemulsification.

Prostaglandin analogues (PGAs) have been associated with the development of pseudophakic macular edema (PME) in complicated cataract cases, but evidence on their effects in uncomplicated phacoemulsification remains controversial. This two-arm, prospective, randomised study included patients with glaucoma or ocular hypertension under PGA monotherapy who were scheduled for cataract surgery. The first group continued PGA use (PGA-on), while the second discontinued PGAs for the first postoperative month and reinitiated use afterwards (PGA-off). Topical non-steroidal anti-inflammatory drugs (NSAIDs) were routinely administered to all patients during the first postoperative month. The patients were followed up for three months and the primary outcome was PME development. Secondary outcomes were corrected distance visual acuity (CDVA), central and average macular thickness (CMT and AMT), and intraocular pressure (IOP). The analysis included 22 eyes in the PGA-on group and 33 eyes in the PGA-off group. No patient developed PME. CDVA was not significantly different between the two groups (p = 0.83). CMT and AMT showed a small but statistically significant increase until the end of follow-up (p < 0.001). Mean IOP values had no significant differences between the groups at each visit (p > 0.05). At the end of follow-up, the IOP values were significantly lower than baseline in both groups (p < 0.001). In conclusion, PGA administration with concomitant topical NSAIDs appears to be a safe practice in the early postoperative period of uncomplicated phacoemulsification.

Conjunctival Pigmentation Following Pars Plana Vitrectomy (PPV) for Rhegmatogenous Retinal Detachment: Risk Factors and Outcomes.

PURPOSE:  To investigate the incidence and the risk factors for conjunctival pigmentation at the sclerotomy sites following valved and non-valved cannula pars plana vitrectomy (PPV) performed by different surgical techniques. METHODS:  This is a prospective observational study which included 70 eyes of 70 patients who underwent PPV for rhegmatogenous retinal detachment with follow-up visits at 1, 3, 6, 12, and 24 months. Twenty-eight eyes were operated using 25G non-valved cannulas (Group A), 22 eyes using 25G non-valved cannulas (Group B), and 20 eyes using 25G valved cannulas (Group C). The evaluated clinical parameters include the surgical technique, the patients' age, the number of retinal tears, the tamponade agent, the presence of residual sub-retinal fluid (SRF), and the duration of postoperative posturing. RESULTS:  Group A was associated with significant conjunctival pigmentation at up to 6 months after PPV. Sulfur hexafluoride (SF6) gas tamponade was associated with less conjunctival pigmentation at 3 months follow-up visit [odds ratio, OR 0.09 (95% confidence interval, CI 0.01; 0.67)], whereas the presence of residual SRF was a significant risk factor for postoperative pigmentation at 1-year follow-up visit [OR 5.89 (95% CI 1.84; 23.12)]. The area of measured pigmentation was also positively correlated to the number of retinal tears at all follow-up visits over 2 years. Six patients presented with conjunctival pigmentation at 2 years follow-up visit. CONCLUSION:  New vitrectomy techniques with valved cannulas prevent the postoperative appearance of conjunctival pigmentation. The number of retinal tears, the presence of SRF, and the use of long-standing tamponade agents were the most significant predisposing factors. The post-vitrectomy conjunctival pigmentation gradually reduces over time.

Repeatability of corneal pachymetry and epithelial thickness measurements with spectral-domain optical coherence tomography (SD-OCT) and correlation to ocular surface parameters.

PURPOSE: To assess the repeatability of corneal pachymetry and epithelial thickness measurements with spectral-domain optical coherence tomography (SD-OCT) and identify correlations between epithelial thickness and ocular surface parameters. METHODS: Adults who happened to have prolonged computer use were recruited, excluding those with conditions interfering with corneal measurements or tear production. All subjects filled in the ocular surface disease index (OSDI) questionnaire. Three consecutive measurements of central and peripheral corneal and epithelial thickness were performed with SD-OCT (RTVue XR). Schirmer test I and tear film break-up time (TBUT) were performed. Repeatability was evaluated with intraclass correlation coefficient (ICC), coefficient of variation and repeatability limit. Spearman correlation was used for non-parametric variables. RESULTS: 113 eyes of 63 subjects were included in the study. ICC was ≥ 0.989 for all corneal and ≥ 0.944 for all epithelial pachymetry segments. The best repeatability was found centrally and the worst superiorly both for corneal and epithelial measurements. Central epithelial thickness was weakly correlated with Schirmer test I (rho = 0.21), TBUT (rho = 0.02), OSDI symptoms and OSDI score (rho <|0.32|). OSDI symptoms and OSDI score were weakly correlated with Schirmer test I (rho <|0.3|) and TBUT (rho <|0.34|). CONCLUSION: RTVue XR measurements of corneal and epithelial thickness are highly repeatable in all segments. The lack of correlation between epithelial thickness and ocular surface parameters could suggest the assessment of epithelial integrity with reliable methods such as SD-OCT.

When should cataract surgeons seek assistance from experienced colleagues?

PURPOSE: To assess which cases should be assorted exclusively to high-volume surgeons and identify when should a cataract surgeon seek assistance from a senior colleague. METHODS: The medical records of 2853 patients with age-related cataract were reviewed. Preoperative risk factors were documented for each case, and they were divided into surgeons who had more (> 400 surgeries/year) or less experience (< 400 surgeries/year). Ophthalmology residents were excluded from this review. The cases that involved posterior capsule rupture, dropped nucleus, zonular dehiscence and anterior capsular tear with or without vitreous loss were defined as "complicated". RESULTS: From the 3247 cataract extraction surgeries that were reviewed, we were unable to identify any statistically significant difference in the complication rates between the two surgeon groups. In the stepwise regression analysis, both groups supported advanced age (> 85) and mature cataracts with up to fourfold odds ratios (OR). Low-volume surgeons had a fivefold OR in the presence of phacodonesis and a fourfold OR in the case of posterior polar cataract. Finally, the low- and high-volume groups had their highest complication rates in the cumulative four and five risk factors, respectively. CONCLUSION: In the presence of advanced age, mature cataracts, phacodonesis and posterior polar cataract, the complication rates appear to be higher for the less experienced surgeons. Meticulous preoperative assessment with detailed documentation of each patient's risk factors can result in fewer complications. The medical complexity of each case can be used as indicator of whether a more experienced surgeon should perform the surgery or not.

Comparison of two protocols of diode laser transscleral cyclophotocoagulation in refractory glaucoma.

INTRODUCTION: Diode laser transscleral cyclophotocoagulation (DLTSCPC) remains the most commonly used cyclodestructive procedure. Nonetheless, there is no common consensus on a standardized technique. METHODS: In this prospective randomized pilot study we compare the "pop"-titrated and "slow-burn" DLTSCPC techniques for a follow-up period of 3 months. The major outcomes of this study were intraocular pressure (IOP) before and after the procedure and the incidence of adverse events. Furthermore, postoperative pain, postoperative intraocular inflammation and corrected distance visual acuity (CDVA) were evaluated. RESULTS: Mean baseline IOP decreased from 37.9 ± 12.7 mmHg in the pop group and 41.2 ± 9.6 mmHg in the slow-burn group to 20.3 ± 13.9 mmHg and 21.3 ± 13.4 mmHg at the final follow-up visit, corresponding to a 45.8 ± 31.7% and 46.3 ± 32.6% reduction respectively. 64.3% and 57.1% of patients had IOP ≥6 and≤ 21 mmHg in the pop and slow-burn groups respectively. The occurrence of adverse events was similar in both groups, with 1 case of hyphema in the pop group and 2 cases in the slow-burn group, and 1 case of hypotony in each group. Mean CDVA remained unchanged until the end of follow-up from 2.05 ± 0.84 to 2.04 ± 0.8 logMAR in the pop group and from 1.93 ± 0.78 to 1.89 ± 0.7 logMAR in the slow-burn group. Nonetheless, 4 eyes in each group encountered CDVA loss. Postoperative pain and inflammation were also similar between groups. DISCUSSION: At the 3rd postoperative month, safety and efficacy was similar in the two techniques. The relative ease of the slow-burn technique may make its application more appealing to ophthalmic surgeons beyond glaucoma specialists.

Descemet's Stripping Automated Endothelial Keratoplasty Using Donor Tissue from an 83-Day-Old Infant.

Purpose: To report a case of Descemet stripping automated endothelial keratoplasty (DSAEK) combined with phacoemulsification in an adult recipient using endothelial graft from an 83-day-old infant donor. Methods: A corneoscleral button was obtained from an infant donor and a DSAEK graft was prepared using a microkeratome. In comparison to the standard technique of DSAEK graft preparation some modifications were made in order to avoid inadvertent perforation, as the donor cornea had a very spherical shape, probably due to the very young age of the donor. The DSAEK graft was transplanted to the left eye of a 68-year-old woman suffering from Fuchs' endothelial dystrophy. Her preoperative best-corrected visual acuity (BCVA) in that eye was 20/100 and central corneal thickness 831 µm. Results: An uneventful DSAEK combined with phacoemulsification was performed. The main complication noted was detachment of the peripheral part and contraction of the corneal graft, observed two months after the procedure. The implanted tissue remained centrally attached with a BCVA of 20/40, 3 years postoperatively. Conclusion: This case report highlights the difficulties emerging from preparation and implantation using an endothelial graft tissue from the youngest ever reported donor.

Late-onset interface fluid syndrome: A case report and literature review.

PURPOSE: To present a case of late-onset interface fluid syndrome (IFS) and a literature review on this rare clinical entity. INTRODUCTION: IFS is an uncommon complication of laser in situ keratomileusis (LASIK). Although generally appearing in the early postoperative period, IFS has been reported even years after LASIK. METHODS: A case report of IFS manifesting 19 years after uneventful LASIK, which prompted a literature search for similar, late-onset cases in MEDLINE PubMed. This article reports on a case of IFS appearing 19 years after LASIK surgery, including extensive patient history and analytical presentation of clinical findings, ancillary testing, and short-term follow-up. Furthermore, a literature search for similar cases was performed on MEDLINE, focusing on the etiology and management of late-onset IFS. RESULTS: Through thorough ancillary testing, the interface fluid was attributed to elevated intraocular pressure (IOP) arising from primary open-angle glaucoma. Antiglaucoma drops resulted in complete fluid regression. A narrative review was conducted based on the 29 case reports that were recovered from the literature search. CONCLUSION: IFS represents an uncommon complication that could appear years after LASIK. Careful clinical examination and anterior segment optical coherence tomography promote early diagnosis. Similar cases may manifest due to elevated IOP of variable etiology or as a result of endothelial dysfunction. Depending on the etiology, IOP control or keratoplasty may resolve the condition.

Factors predisposing to intraoperative floppy-iris syndrome: An up-to-date meta-analysis.

Intraoperative floppy-iris syndrome (IFIS) is an increasingly recognized condition that is proven to lead to higher rates of intraoperative complications. This study provides an updated systematic review and meta-analysis regarding all the identified factors predisposing to IFIS. The study was performed in accordance with the PRISMA guidelines. 38 studies were finally included in the meta-analysis. The factors that were found to predispose to IFIS significantly were male sex (odds ratio [OR], 4.25; CI, 2.58-7.01), hypertension (OR, 1.55; CI, 1.01-2.37), tamsulosin (OR, 31.06; CI, 13.74-70.22), finasteride (OR, 4.60; CI, 1.97-10.73), benzodiazepines (OR, 2.88; CI, 1.17-7.12), and antipsychotics intake (OR, 6.91; CI, 2.22-21.50). A decreased dilated pupil preoperatively was found predisposing to IFIS (weighted mean difference -0.93; CI, -1.19 to -0.67). Intracameral epinephrine, which was investigated as a potential prophylactic measure for preventing IFIS, did not reach statistical significance (OR, 0.29; CI, 0.08-1.06). A comprehensive preoperative assessment of all risk factors is vital to stratify the surgical risk, which is crucial in addressing IFIS because unanticipated IFIS could turn a routine surgery into one of significant visual morbidity.

Part-time Versus Full-time Spectacles for Myopia Control (ParMA Study): A Randomized Clinical Trial.

Introduction To compare myopia progression in school-aged children of Caucasian origin wearing part-time vs. full-time full correction with single-vision spectacles. Methods This prospective, randomized controlled trial included 30 children with bilateral myopia, who received either full-time or part-time treatment with single-vision spectacle lenses. Myopia progression was assessed as the mean change in cycloplegic spherical equivalent refraction (SE), mean change in axial length (AL), and mean change in sub-foveal choroidal thickness (SChT), over a 12-month follow-up period. Results A total of 32 eyes were treated with part-time single-vision spectacles (intervention group) and 28 eyes with full-time single-vision spectacles (control group), respectively. The part-time treated group reported no spectacle use during near-work activities for a mean of 6.2 hours/day. At the 12-month assessment, there was no significant difference between part-time and full-time correction groups in mean SE change (MD: -0.05 D, 95% CI: -0.50 - 0.39 D; P 0.81), in mean AL change (MD: -0.07 mm; 95% CI: -0.20 - 0.06 mm; P 0.30), and in mean SChT change (MD: -11.45 µm; 95% CI -22.60 - 14.16 µm; P 0.67). Conclusion Myopia progression in Caucasian children treated with part-time, single-vision spectacle use was not different compared to full-time, single-vision spectacle use, over a 12-month follow-up period.

The process of estimating the cost of surgery: Providing a practical framework for surgeons.

Over the last decades, health care costs have been increasing at an alarming, exponential rate which is considered unsustainable. Surgical care utilizes one-third of health care costs. Estimating, evaluating, and understanding the cost of surgery is a vital step towards cost management and reduction. Current cost estimation studies and cost-effectiveness studies have vast disparities in their methodology, with published costs of Operating Room varying from as low as $7 and as high as $113 per minute. Costs in surgery are distinguished as direct and indirect. Allocation of direct costs involves identification, measurement, and valuation processes. Allocation of indirect costs involves the allocation of capital and overhead costs and of indirect department costs. Annualised capital costs and overhead hospital costs are then allocated to surgery by either the cost-centre allocation or the activity-based allocation frameworks. Indirect department costs are allocated to a specific surgery by weighted service allocation or hourly rate allocation or inpatient day allocation, or marginal markup allocation. The growing societal, financial and political pressure for cost reduction has brought cost analysis to the forefront of healthcare discussions. Thus, we believe that almost every single surgeon will eventually enter the field of healthcare economics by necessity. This review aims to provide surgeons with a practical framework for engaging in cost estimation studies.

Ocular parameter changes after phacoemulsification in pseudoexfoliative eyes: case-control study.

PURPOSE: To assess changes of angle morphometric parameters, anterior chamber depth (ACD), intraocular pressure (IOP), and endothelial cell density (ECD) after uneventful phacoemulsification in eyes with pseudoexfoliation syndrome (PEX) compared with those in eyes without PEX and to evaluate the effect of these changes on effective lens position and postoperative refraction. SETTING: Papageorgiou Hospital, Thessaloniki, Greece. DESIGN: Prospective case-control study. METHODS: Angle opening distance, trabecular-iris space area, and scleral spur angle width were measured using anterior segment optical coherence tomography. ACD was assessed using IOLMaster and ECD using specular microscopy. All parameters were evaluated at baseline and 2 months postoperatively. RESULTS: 42 patients (42 eyes) with PEX and 39 patients (39 eyes) without PEX who underwent uneventful phacoemulsification were enrolled. All angle parameters and ACD increased significantly after phacoemulsification in both groups ( P < .001), with no statistically significant difference between them ( P > .05). Percentile change in ACD was greater in PEX eyes ( P = .017). Regarding the mean refractive prediction error, no statistically significant differences were found between the study groups ( P = .68). A statistically significant trend toward hyperopic shift was noted in the PEX group ( P = .039). IOP and ECD diminished postoperatively in both groups, with no statistically significant difference between the study groups ( P = .09 and P = .22, respectively). CONCLUSIONS: PEX, compared with non-PEX eyes, demonstrated a greater anterior chamber deepening and a hyperopic shift after phacoemulsification. These could be related to the zonular laxity in eyes with PEX and imply that PEX eyes may require a modified target refraction to achieve the desired refractive outcome.

Silodosin as a predisposing factor of intraoperative floppy iris syndrome (IFIS): an observational propensity score-matching cohort study.

PURPOSE: To evaluate the correlation between silodosin and intraoperative floppy iris syndrome (IFIS) and compare it with other a1-adrenergic receptor antagonists (a1-ARAs) and other factors predisposing to IFIS. METHODS: From the patients who underwent phacoemulsification between 2014 and 2020, we identified all patients who, during their preoperative assessment, reported an a1-ARAs intake (exposed group). These patients were matched utilizing a propensity score matching analysis with an otherwise homogenous group of patients (control group) based on demographics and systemic/ocular comorbidities. RESULTS: A total of 350 patients were included in each group. In the exposed group, 177 (50.6%) patients were exposed to tamsulosin, 105 (30%) to alfuzosin, 43 (12.2%) to silodosin. Regarding IFIS, it was observed in 21.5% of patients on tamsulosin (38/177), 11.4% on alfuzosin (12/105), 37.2% on silodosin (16/43), and 3.4% in the controlled group (12/350). In a multiple regression model analysis, the only two factors significantly associated with IFIS development were silodosin and tamsulosin yielding an adjusted odds ratio of 8.471 (95%CI 4.005-17.920) and 3.803 (95%CI 2.231-6.485), respectively. CONCLUSION: Silodosin has been demonstrated as a predisposing factor, strongly correlated with IFIS development. These results should increase cataract surgeons' awareness to assess their patients preoperatively for exposure to silodosin carefully and employ the appropriate prophylactic measures to ameliorate the impact of silodosin intake on the surgical outcome.

Corectopia grading: A novel classification system.

OBJECTIVES: To present and validate the novel grading system for objective classification of corectopia. SUBJECTS AND METHODS: We evaluated 28 eyes of 28 patients with or without corectopia and validated the grading and classification system for corectopia according to three major criteria: (i) direction, (ii) extent, and (iii) alteration of mydriasis. Intraclass correlation coefficient (ICC) and inter-rater agreement between 7 inexperienced and 1 experienced ophthalmologist against a golden standard (GS) were calculated. RESULTS: The ICC for the 7 inexperienced ophthalmologists regarding the grading of direction and centration of the pupil was 0.83 (95% confidence interval (CI), 0.74 to 0.90; p < .001) and 0.57 (95% CI, 0.43 to 0.72; p < .001), respectively. The inter-rater agreement was the same or almost the same in cases of pupil decentration between the inexperienced, experienced ophthalmologists and the GS (k = 0.82; 95% CI, 0.64-1.00; p < .001). In assessing the direction of pupil displacement, the inter-rater agreement was almost perfect between the inexperienced (k = 0.93; 95% CI, 0.84-1.00; p < .001) and experienced (k = 0.92; 95% CI: 0.82-1.02; p < .001) ophthalmologists and the GS. CONCLUSION: The first detailed clinical classification is proposed for objective corectopia grading particularly relevant in documenting and assessing progressive disease. It was confirmed to be acceptable for clinical use by inexperienced and experienced ophthalmologists alike.

'The role of accommodative function in myopic development: A review.'

Involvement of the accommodative mechanism in myopia progression has been hypothesised and investigated over the past years. The initial stimulus for accommodation is derived from near work, in an attempt of the eye to obtain a clear image. When there is a lag in accommodative response, the resulting blurred retinal image is believed to precipitate axial elongation and lead to myopia development. Given the myopia crisis across the globe, the phenomenal connection between the accommodative mechanism and myopia development warrants further investigation. The dynamic accommodative functions implicated in binocular vision evaluation include the accommodative accuracy, amplitude and facility. Association of these accommodative parameters to current treatment options for myopia control is of great clinical interest. Effective treatments, including orthokeratology, multifocal lenses and atropine eyedrops, appear to induce changes in the dynamic accommodative response. This review aims at investigating the clinical role of accommodative function in myopia development and at exploring its use as a promising myopia-monitoring tool.

Reliability of Refraction, Keratometry, and Intraocular Pressure Measurements with an Automated All-in-one Device.

SIGNIFICANCE: This study explores the reliability of TonoRef II (Nidek, Tokyo, Japan), which represents a simple tool to obtain rapid refractometry and tonometry measurements. The present device demonstrates very high repeatability of refraction and intraocular pressure (IOP) readings as compared with subjective measurements and a higher concordance of IOP readings to Goldmann application tonometry (GAT). PURPOSE: This study aimed to evaluate the repeatability of measurements acquired with the Autorefractometer/Keratometer/Tonometer TonoRef II and assess their agreement to subjective measurements and readings of other established devices. METHODS: In a cross-sectional study, 54 eyes of 54 healthy subjects were enrolled. Each subject underwent five measurements with the TonoRef II, three measurements with the Canon RK-F1 Autorefractor Keratometer (Canon Europe NV, Amstelveen, the Netherlands), three IOP measurements with the Canon TX-F Noncontact Tonometer (Canon Inc., Tokyo, Japan), three measurements with GAT, and a thorough subjective refraction. Repeatability coefficient (r), intraclass correlation coefficient (ICC), and Bland-Altman plots were used to evaluate repeatability of readings and agreement to the subjective values. RESULTS: TonoRef II showed high repeatability (ICC >0.9) in all parameters tested (sphere, r = 0.157; cylinder, r = 0.196; IOP, r = 2.653). A strong correlation was found between TonoRef and Canon instruments (P < .001 in all parameters). Mean differences and limits of agreement (mean ± 1.96 standard deviation) were -0.01 ± 0.69 D, -0.11 ± 0.7 D, and 2.1 ± 3.4 mmHg for sphere, cylinder, and IOP, respectively. Both autorefractors achieved a very good to excellent agreement to the values obtained with the subjective refraction for most of the parameters tested, without any significant difference to each other (P > .05). Intraocular pressure measurements of TonoRef II showed higher agreement to the GAT values compared with those obtained with the Canon tonometer (ICC, 0.9114 and 0.7002, respectively; P < .001). CONCLUSIONS: Intraocular pressure and refraction readings acquired with TonoRef II demonstrate very high repeatability and agreement to the subjective measurements. Regarding IOP evaluation, TonoRef II shows higher concordance to GAT compared with another established noncontact tonometer.