Factors Affecting the Results of Ahmed Glaucoma Valve Implantation in Diabetic Neovascular Glaucoma With or Without Previous Pars Plana Vitrectomy.

Objectives: The aim of this study was to compare the outcomes of Ahmed glaucoma valve implantation (AGVI) in neovascular glaucoma (NVG) due to proliferative diabetic retinopathy (PDR) with or without a pars plana vitrectomy (PPV) history and to analyze the factors affecting surgical failure. Methods: Patients with NVG secondary to PDR undergoing AGVI at a single center were reviewed retrospectively. The surgical failure rates and post-operative complications were compared between eyes with (PPV-AGVI group) and without previous PPV (AGVI group). Failure was defined as loss of light perception or intraocular pressure (IOP) >17 mmHg despite maximum medication, or need of additional intervention for IOP control or for the management of complications. Survival analysis was investigated by Kaplan-Meier test. The possible factors for failure were analyzed with logistic regression analysis. Results: The failure rates were 21.9% during the mean follow-up of 27.56±15.38 months and 14.3% during 23.63±12.38 months, in PPV-AGVI group (n=32) and in AGVI group (n=49), respectively (p=0.37). The frequency of complications and surgical intervention need for management of post-operative complications was similar between groups (p>0.05). There was no significant difference in survival analysis (p=0.13). The history of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection before AGVI was significantly associated with failure (odds ratio = 26.941, p=0.02). Conclusion: The results of AGVI performed with long scleral tunnel technique were comparable in terms of failure rates, between NVG patients with and without previous diabetic vitrectomy. The only significant factor for failure was intravitreal anti-VEGF pre-treatment. This may be related to the necessity of anti-VEGF therapy in aggressive PDR, and also, anti-VEGF agents may increase fibrosis in the anterior chamber angle.

Evaluation of Anterior Scleral Thickness and Angle Parameters in Eyes with Pseudoexfoliation Syndrome and Glaucoma.

PRCIS: The relationship between anterior scleral thickness (AST) and scleral spur (SS) length was disrupted in eyes with pseudoexfoliation (PX), and SS length was shorter in eyes with pseudoexfoliative glaucoma (PXG). OBJECTIVES: To evaluate AST in eyes with PX and to examine the relationship between AST and Schlemm canal (SC), trabecular meshwork (TM), and SS. PATIENTS AND METHODS: Thirty-eight patients with PX syndrome (PXS), 38 patients with PXG, and 38 healthy patients were included in the study. Using sweep source anterior segment optical coherence tomography, AST (0, 1, 2, and 3 mm from the SS), SC, and TM were visualized in the nasal and temporal areas, and measurements were compared between groups. The relationships between corneal thickness, TM, SS, SC, and AST were then evaluated. RESULTS: In all groups, the AST, SC, and TM measurements were similar ( P > 0.05). In the PXG group, SS lengths in the temporal area were shorter than those in the control and PXS groups ( P = 0.012). There were significant correlations between TM length and AST in the PXG group ( P < 0.05). The SS length exhibited moderately positive correlations with SC length and mean TM thickness in the PXG ( P < 0.05). There was a significant relationship between AST0 and SS in healthy eyes ( P < 0.05), but not in other eyes. CONCLUSIONS: The shorter SS length observed in eyes with PXG may be a sign of structural changes. In addition, disruption of the relationship between AST and SS may be an early sign of pathologic processes, especially in eyes with PXS, and may require closer follow-up of these eyes.

The effect of uneventful cataract surgery on Schlemm's canal and the trabecular meshwork in cases with pseudoexfoliation.

PURPOSE: To evaluate the effect of uneventful cataract surgery on Schlemm's canal (SC) and the trabecular meshwork (TM) in cases with pseudoexfoliation (PX). METHODS: In this prospective study, 37 PX and 37 normal eyes, who underwent cataract surgery, were included. The PX group was further divided into two subgroups: PX syndrome (PXS) and PX glaucoma (PXG). Preoperative complete ophthalmologic examination, anterior segment (AS) imaging using a Scheimpflug camera, and measurements of SC length and area and TM thickness and length using AS optical coherence tomography (AS-OCT) were performed in all cases. All measurements were repeated at the first and third months after surgery. RESULTS: Preoperative intraocular pressure (IOP), AS parameters, SC, and TM values showed no significant differences between the groups (p > 0.05). After surgery, there was a significant increase in AS parameter values and a significant decrease in IOP values in both the PX and control groups (p < 0.05). The nasal and temporal SC area showed a significant increase in the PX group after surgery (p = 0.007, p = 0.003, respectively). In the subgroup analysis, the only significant change in the nasal and temporal SC area was in the PXS group (p = 0.006, p = 0.003, respectively). CONCLUSION: Cataract surgery resulted in an increase in the SC area in patients with PXS. This increase may be due to multiple mechanisms including the IOP-lowering effect of cataract removal, change in AS, and removal of intraocular PX material after surgery.

Anterior Segment Changes and Refractive Outcomes after Cataract Surgery Combined with Gonioscopy-Assisted Transluminal Trabeculotomy in Open-Angle Glaucoma

Objectives: To compare the accuracy of intraocular lens (IOL) calculation formulas in patients undergoing phacoemulsification combined with gonioscopy-assisted transluminal trabeculotomy (phaco-GATT) and to determine the predictive factors for refractive errors. Materials and Methods: Fifty-three eyes of 53 patients undergoing phaco-GATT were retrospectively reviewed. The preoperative and postoperative 3-month anterior segment (AS) parameters were measured by Scheimpflug camera. The mean prediction error (PE), mean absolute error (MAE) in the Sanders-Retzlaff-Kraft/theoretical (SRK/T), Barrett- Universal II, Hill-radial basis function (Hill-RBF) and Kane formulas were compared. The influence of biometric parameters on PE were analyzed by correlation analysis. Results: Postoperatively, there was a statistically significant decrease in axial length (AL) and significant enlargement in anterior chamber depth (ACD), anterior chamber angle (ACA), and anterior chamber volume (p<0.001). The mean PE using SRK/T (-0.08 diopters [D]) was more myopic than in the Barret (0.01 D) and Hill-RBF (0.01 D). The PE closest to zero was in the Kane formula (0.001 D). The Kane formula provided a lower MAE (0.30±0.28 D) than the SRK/T (0.38±0.32 D) and Barrett (0.36±0.30 D) (p<0.001). The MAE in Hill-RBF (0.32±0.28) was comparable with that in Kane (p=0.02). Preoperative AL was significantly associated with PE in all formulas except Kane. Barrett was the only formula that did not have a significant correlation between PE and postoperative ACD and ACA. Conclusion: The Kane formula may provide higher predictability of the IOL power calculation than the SRK/T and Barrett-Universal II formulas in phaco-GATT surgery, which can cause significant changes in the AS and AL.

Changes in pupil size, ocular wavefront aberrations, and accommodation in healthcare workers using FFP3 masks.

PURPOSE: To evaluate changes in pupil size, ocular wavefront aberrations (WA), and accommodation in healthcare workers after 4-h usage of Filtering Facepiece class 3 (FFP3) masks. MATERIAL AND METHODS: This prospective study included 22 healthy healthcare workers. Pupil size, ocular WA, and accommodation changes before and after FFP3 mask usage were evaluated using a Hartmann Schack aberrometer. Accommodative responses to stimulus ranging from 0 to 5 diopters (D) in increments of 0.5 D were assessed. Ocular high-order aberrations (HOAs) were recorded at baseline and at every accommodative stimulus. Oxygen saturation (SpO2) was measured by pulse oximetry before and after the mask usage. RESULTS: The mean age was 36.6 ± 8.5 years. The SpO2 significantly decreased from 98.95 to 97.95% after usage of the FFP3 mask (p < 0.001). The mean pupil size did not significantly differ before (6.22 ± 0.75 mm) and after (6.38 ± 0.83 mm) the 4-h mask usage (p = 0.093). The mean total RMS of the total HOAs was 0.36 ± 0.17 before and 0.39 ± 0.15 after the mask usage (p = 0.071). Post-mask accommodation showed a significant decrease at the 2 D (p = 0.041), 2.5D (p = 0.022), and 3 D (p = 0.025) stimuli. CONCLUSION: The present study shows that after 4 h-usage of FFP3 mask, both SpO2 and accommodative response to increasing stimuli might be significantly decreased.

Lens factor as an underlying mechanism in primary angle closure with gonioscopically-visualized ciliary body processes.

PURPOSE: To compare the differences in anterior segment parameters between eyes with primary angle closure (PAC) with and without gonioscopically-visualized ciliary body processes (CBP). STUDY DESIGN: Prospective, observational, comparative clinical study. METHODS: Detailed ocular examinations and gonioscopy were performed in 89 eyes of 89 patients with PAC to determine the visibility of the CBP. Anterior chamber depth (ACD), anterior chamber width, lens thickness (LT), lens vault (LV) and pupil diameter were determined using ultrasound biomicroscopy. The lens-axial length factor (LAF) and relative lens position (RLP) were calculated. All parameters were compared between eyes with and without gonioscopically visible CBP (PAC+CBP and PAC-CBP groups) after adjusting for age and gender. The association of the parameters with visible CBP was analyzed by univariate logistic regression analysis. RESULTS: PAC+CBP group included 41 eyes and the PAC-CBP group, 48 eyes. The axial length and ACD were statistically significantly smaller (p = 0.009 and p = 0.005, respectively) and LT, LV and LAF were statistically significantly greater (p = 0.03, p = 0.008 and p = 0.004, respectively) in the PAC+CBP group. In the PAC eyes with glaucoma, the LT, LV and LAF were statistically significantly greater in the PAC+CBP group (p = 0.02, p = 0.001 and p = 0.02, respectively). The LAF had the strongest association with visible CBP in the regression analysis (Odds ratio = 141.70, p = 0.002). CONCLUSION: Gonioscopical visualization of ciliary processes may suggest that anterior segment crowding, especially lens factor is the underlying mechanism in PAC. It may provide a practical gonioscopic examination method for predicting the predominant pathophysiology of PAC.

Factors defining the intraocular pressure-lowering effect of phacoemulsification and laser peripheral iridotomy in patients with primary angle closure : Factors defining IOP lowering effect of PE and LPI in PAC.

To identify whether gonioscopic ciliary body visibility and factors including anterior chamber depth (ACD), axial length (AL), acute attack history, and preoperative intraocular pressure (IOP) had any effect on IOP decrease in primary angle closure (PAC) and primary angle-closure glaucoma (PACG) after phacoemulsification (PE) and/or laser peripheral iridotomy (LPI). This retrospective-design study was conducted with 81 eyes with PAC and PACG; 33 eyes whose IOP was controlled with LPI and PE constituted group 1, and 48 eyes whose IOP was controlled using LPI alone comprised group 2. The effects on preoperative and last-visit IOP levels, ciliary body visibility, ACD, AL, and acute attacks were analyzed. Eyes within the groups were similar in AL, ACD, and preoperative IOP except for acute attack history, which was found to be higher in group 1. For group 1, none of the factors was found to have a differentiative effect on IOP decrease after PE, except eyes with preoperative IOP > 21 mm Hg, which had significantly more IOP reduction. For group 2, no difference was found in ciliary body visibility, and higher or lower ACD. However, eyes with AL ≥ 22 mm, positive acute attack history, and higher preoperative IOP were associated with significantly better IOP reduction. We found no relationship between ciliary body visibility and an IOP-reducing effect of PE and LPI. Although we found PE effective in IOP reduction in all eyes, we determined LPI to have a lesser IOP-reducing effect in eyes with IOP ≤ 21 mm Hg and AL < 22 mm.

Müller Muscle-Conjunctival Resection for Treatment of Contralateral Ptosis following Unilateral External Levator Advancement.

BACKGROUND: One of the main causes of unsatisfactory outcomes after unilateral blepharoptosis surgery is asymmetry of the upper eyelid height, which occurs as a result of a contralateral eyelid droop. Therefore, the authors evaluated the efficacy of Müller muscle-conjunctival resection (MMCR) for the treatment of contralateral ptosis following unilateral external levator advancement (ELA). METHODS: This study analyzed 26 eyelids of 26 patients with upper eyelid height asymmetry following unilateral ELA who underwent contralateral MMCR retrospectively. The phenylephrine test was performed before ELA and before MMCR. The main outcome measures were symmetry outcomes and clinical outcomes. RESULTS: The mean patient age was 55.81 ± 7.98 years (range, 44 to 70 years); 15 were female (57.7%). The Hering dependency was observed in 13 of the patients (50%) before ELA. An adequate response to phenylephrine was observed before MMCR but not before ELA. Symmetry outcomes after MMCR were perfect (<0.5 mm), good (≥0.5 mm and <1 mm), and fair (≥1 mm) in seven, 17, and two patients, respectively. An optimal upper eyelid height was noted in 47 of the 52 eyelids after the MMCR, whereas three of the 52 eyelids had minimal overcorrection, and two eyelids had undercorrection. The mean change in marginal reflex distance 1 of the contralateral eyelid droop was greater for patients with than without the Hering dependency ( P < 0.0001) after ELA but not after MMCR. Two patients (7.6%) underwent revision ELA surgery. CONCLUSION: MMCR and use of the phenylephrine test to predict the eyelid position may represent an alternative approach in patients who require management of contralateral ptosis following unilateral ELA. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Uneventful Phacoemulsification after Trabeculectomy in Pseudoexfoliation Glaucoma versus Primary Open-Angle Glaucoma.

INTRODUCTION: Conflicting results have been reported on phacoemulsification in the filtered eyes with open-angle glaucoma. In this study, we aim to compare the effect of phacoemulsification after trabeculectomy between pseudoexfoliation glaucoma (XFG) and primary open-angle glaucoma (POAG). METHODS: Consecutive patients with XFG and POAG who underwent uneventful phacoemulsification after trabeculectomy with 5-fluorouracil (TRAB-PHACO group) were reviewed retrospectively and matched to patients who underwent trabeculectomy only (TRAB group). Comparisons were performed for IOP, medication numbers, and success rates. Surgical failure was defined as IOP >21 mm Hg or IOP ≤21 mm Hg with additional medication or glaucoma surgery. Survival analysis was investigated by Kaplan-Meier test and the factors influencing final success by multivariate logistic regression analysis. RESULTS: The records of 204 patients were reviewed. In XFG, when compared with the baseline, increase in IOP became statistically significant at the at 24-month visit in the TRAB-PHACO group (p = 0.002), at the 6-month visit (p = 0.001) in the TRAB group and remained so throughout the follow-up. In the TRAB-PHACO group, increase of glaucoma medications was statistically significant only at the last visit (p = 0.001) in XFG, at the 6-month visit (p = 0.02) in POAG and remained so throughout the follow-up. Two glaucoma types did not differ statistically from one another in terms of survival analysis. In the TRAB group, the additional glaucoma surgery was more common in XFG compared to POAG (p = 0.02). The trabeculectomy failure after phacoemulsification was related with an IOP spike >25 mm Hg at postoperative first 24h (p = 0.04). CONCLUSIONS: In the filtered eyes with XFG, uneventful phacoemulsification may delay time-related worsening in IOP control and may decrease the additional glaucoma surgery need.

Pseudoexfoliation Glaucoma as a Predictor of Refractive Surprise After Uneventful Cataract Surgery.

PRCIS: The pseudoexfoliation glaucoma group produced higher mean absolute error (MAE) and higher percentages of large-magnitude prediction error, in all investigated intraocular lens formulas. Postoperative anterior chamber angle and change in intraocular pressure (IOP) were associated with absolute error. PURPOSE: The purpose of this study is to evaluate refractive outcomes of cataract surgery in patients with pseudoexfoliation glaucoma (PXG) and to determine the predictive factors for refractive errors. MATERIALS AND METHODS: Fifty-four eyes with PXG, 33 eyes with primary open angle glaucoma (POAG) and 58 normal eyes undergoing phacoemulsification, in Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey, were included in this prospective study. The follow-up was 3 months. Preoperative and postoperative anterior segment parameters measured by Scheimpflug camera were compared after adjusting for age, sex, and axial length. The mean prediction error, MAE, and percentages of large-magnitude prediction error (>±1.0 D) in SRK/T, Barrett Universal II, and Hill-RBF formulas were compared. RESULTS: There was a significantly greater anterior chamber angle (ACA) enlargement in PXG eyes compared with POAG ( P =0.006) and normals ( P =0.04). The PXG group showed significantly higher MAE in SRK/T, Barrett Universal II, and Hill-RBF (0.72, 0.79, and 0.79 D, respectively) than POAG (0.43, 0.25, and 0.31 D, respectively) and normals (0.34, 0.36, 0.31 D, respectively) ( P <0.0001). The large-magnitude error was significantly more frequent in the PXG group among the 3 groups with SRK/T (37%, 18%, and 12%, respectively) ( P =0.005), Barrett Universal II (32%, 9%, and 10%, respectively) ( P =0.005), and Hill-RBF (32%, 9%, and 9%, respectively) ( P =0.002). The MAE was correlated with postoperative ACA and IOP decrease in Barrett Universal II ( P =0.02 and 0.007, respectively) and Hill-RBF ( P =0.03 and 0.02, respectively). CONCLUSIONS: PXG may be a predictor for refractive surprise after cataract surgery. Prediction errors may be due to IOP-lowering effect of surgery and larger postoperative ACA than expected, in the presence of zonular weakness.

Evaluation of Sudden Visual Loss and Central 10-Degree Visual Field Change Following Glaucoma Surgery in Severe and End-Stage Eyes.

Objectives: The purpose of the study was to evaluate the sudden visual loss and central 10-degree visual field (VF) change following glaucoma surgery in eyes with severe and end-stage glaucoma. Methods: This was a single-center retrospective study. The charts of patients with severe and end-stage glaucoma who had undergone trabeculectomy and Ahmed glaucoma valve (AGV) implantation surgery were reviewed. Patients who had 10-2 Humphrey VF automated (HVFA) at follow-up were included and classified into two following groups: With split fixation on 10-2 HVFA before surgery split fixation group (SFG) and those without split fixation (WSFG). Results: The data of 37 patients in SFG and 28 patients in WSFG were reviewed. The mean follow-up duration was 2.06±0.24 years in SFG and 2±0.3 years in WSFG. 10-2 HVFA revealed that SFG had a mean MD -25.8±5.2 dB preoperatively and -25.2±1.1 dB (p=0.18) at last visit, WSFG had a mean MD -9.8±4.8 dB preoperatively and -10.8±1.5 dB at last visit (p=0.10). In SFG, the mean intraocular pressure (IOP) decreased from 30.1±9.5 mmHg to 12.3±0.62 mmHg (p<0.001), and in WSFG, the mean IOP decreased from 30±6.9 mmHg to 12.3±0.90 mmHg at last visit (p<0.001). There was no statistical difference for visual acuity of both the groups at the follow-up (p=0.30 and p=0.70). In SFG, one patient had wipe-out phenomenon who had undergone AGV surgery. Conclusion: Although wipe-out phenomenon was a rare complication, it can develop not only after trabeculectomy but also after AGV surgery, and patients with split fixation and severe and end-stage glaucoma were at risk for this phenomenon regardless of the type of surgery. Both trabeculectomy and AGV surgery appear to provide stability of the central 10° VF.

The effect of uneventful cataract surgery in pseudoexfoliation glaucoma with or without previous mitomycin C-augmented trabeculectomy.

PURPOSE: To analyze the effect of uneventful cataract surgery on intraocular pressure (IOP) in pseudoexfoliation glaucoma (PXG) eyes with and without a history of Mitomycin C-augmented trabeculectomy. METHODS: Eyes with PXG that had underwent uneventful cataract surgery were enrolled. The IOP and the medication numbers before cataract surgery, and 1, 3, 6, 12, 18, 24 months after cataract surgery, and at the last visit were recorded in PXG with and without previous trabeculectomy. Failure was defined as IOP > 21 or ≤ 21 mmHg with additional medication or surgery. In the postoperative first 24 h, IOP > 50% above baseline was defined as an IOP spike. RESULTS: In the trabeculectomized eyes (n = 37), the increase in the mean IOP (p = 0.024) and the increase in the mean number of medications (p = 0.007) was significant at the last visit when compared with baseline. In the non-trabeculectomized eyes (n = 42) there was a significant decrease in the mean IOP (p = 0.016) and in the mean number of medications (p = 0.038) at the last visit. Twelve eyes (32.4%) in trabeculectomized group and six (14.3%) in the non-trabeculectomized group experienced failure. An IOP spike was seen in one eye in the trabeculectomized group, in 15 eyes in the non-trabeculectomized group (p < 0.0001). The IOP spike was a significant risk factor for failure (p = 0.027). CONCLUSION: Uneventful cataract surgery may have significant negative effect on the IOP control in the trabeculectomized PXG eyes. After cataract surgery, the non-trabeculectomized PXG eyes had a higher risk of IOP spike and an IOP spike may be a risk factor for failure.

Analysis of risk factors and ocular hypotony characteristics in choroidal detachment after penetrating glaucoma surgery.

PURPOSE: To analyze the risk factors and ocular hypotony characteristics of choroidal detachment (CD) after penetrating glaucoma surgery and to compare between eyes with and without CD. METHODS: This retrospective study enrolled 173 eyes of 168 patients. Patients who underwent trabeculectomy or Ahmed glaucoma valve implantation due to medically uncontrolled glaucoma and who had intraocular pressure (IOP) < 9 mmHg at any time during the first postoperative week were included. RESULTS: The study population consisted of 61 (36.3%) females and 107 (63.7%) males with a mean age of 60.7 ± 14.2 years. The postoperative median follow-up time was 24 months (range, 12-40 months). Postoperatively, CD developed in 47 (27.1%) eyes. Multivariate analyses demonstrated that eyes with high preoperative IOP (> 40 mmHg) were 12.1 times more likely to develop CD (p = 0.000) and that presence of IOP < 9 mmHg on the first day of surgery increased the CD risk 3.8 times (p = 0.002); male gender raised the risk 2.7 times (p = 0.028). The mean preoperative IOP in CD eyes was significantly higher than in non-CD eyes (p = 0.000). The mean IOP change between preoperative and lowest IOP was significantly greater in those with CD than in those without CD (p = 0.000). The mean lowest IOP in the CD eyes was significantly lower than in the non-CD eyes (p = 0.037). For the surgical failure rate, no significant difference was found between the CD and the non-CD groups (p = 0.14). CONCLUSIONS: The present study demonstrated that high preoperative IOP, presence of IOP < 9 mmHg on the first postoperative day, and male gender were significantly associated with CD after penetrating glaucoma surgery. Choroidal detachment accompanied by hypotony did not affect the final outcome negatively.

Effects of menopause on the retinal nerve fiber layer and ganglion cell complex and on intraocular pressure.

OBJECTIVE: To compare the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness and intraocular pressure in reproductive age and postmenopausal women. METHODS: The study included 94 eyes of 47 reproductive age women (Group 1) and 94 eyes of 47 postmenopausal women (Group 2). In all women, RNFL and GCC thicknesses were measured by optical coherence tomography. Intraocular pressure levels were measured by Goldmann applanation tonometry. Generalized linear mixed models were conducted to test the differences between groups. Age- and body mass index (BMI)-adjusted partial correlation analysis was used to examine the associations between parameters. RESULTS: There was a statistically significant difference in age and BMI between the two groups (P<0.001, P<0.001, respectively). There was no difference in all RNFL and GCC values between the reproductive age and postmenopausal women. The duration of postmenopause versus average, superior hemisphere, and superior values of RNFL and superior and inferior values of GCC were positively correlated with statistical significance in age- and BMI-adjusted partial correlation coefficient tests (r = 0.254, P = 0.017; r = 0.303, P = 0.004; r = 0.317, P = 0.003; r = 0.301, P = 0.004; r = 0.313, P = 0.003; r = 0.271, P = 0.011, with 95% confidence, respectively). CONCLUSIONS: In this study, there was no significant difference in all RNFL and GCC values between the reproductive age and postmenopausal women after adjusting for age and BMI. However, we observed that a long postmenopausal period was associated with higher RNFL and GCC values.

Refractive Outcomes of Uneventful Cataract Surgery in Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma.

PURPOSE: To compare the refractive outcomes after cataract surgery between patients with and without pseudoexfoliation, and to evaluate the risk factors of refractive error. METHODS: Retrospective review of 210 eyes with pseudoexfoliation (study group) and 510 normal eyes (control group) that underwent uneventful phacoemulsification with intraocular lens implantation. The study group included pseudoexfoliation syndrome and pseudoexfoliation glaucoma (PXG) subgroups. The main outcome measure was refractive error, defined as the difference between the target refraction and postoperative refraction in diopter (D). A refractive error >±1.0 D was identified as a large-magnitude refractive error. The frequency of the large-magnitude refractive error was compared between study and control groups, and also between each subgroup and normal eyes. The factors influencing refractive error were analyzed by logistic regression. RESULTS: There was a significantly higher frequency of a refractive error >± 1.0 D and hyperopic error >1.0 D in the study group than in the control group (p = 0.001 and p = 0.003, respectively). In the multivariate logistic regression analysis, PXG and poor preoperative visual acuity were related with a large-magnitude refractive error (p = 0.001 and p = 0.02, respectively) Refractive error >± 1.0 D and hyperopic error >1.0 D were noted more often in PXG eyes that had an intraocular pressure spike >25 mmHg at postoperative first 24 hours (p = 0.01 and p=0.03, respectively). CONCLUSIONS: The eyes with pseudoexfoliation were at a high risk for refractive error, especially in the presence of glaucoma. In PXG, the only significant risk factor for refractive error was observed to be the presence of an intraocular pressure spike.

Efficacy of the Müller Muscle-Conjunctival Resection for the Correction of Unilateral Ptosis following External Levator Operations in Patients with Bilateral Involutional Ptosis.

SUMMARY: Patients with aponeurotic blepharoptosis who are treated with external levator advancement may experience complications such as upper eyelid height asymmetry and often require revision surgery. The authors assessed the efficacy of Müller muscle-conjunctival resection in cases with upper eyelid height asymmetry following bilateral external levator advancement. The authors used retrospective analysis of 11 cases between September of 2016 and October of 2018 with eyelid asymmetry following bilateral external levator advancement. Following a positive phenylephrine test, these patients underwent unilateral Müller muscle-conjunctival resection revision surgery to treat the undercorrected eyelid. Preoperative and postoperative marginal reflex distance 1, symmetry outcomes, and clinical outcomes of patients were evaluated after the Müller muscle-conjunctival resection. The average patient age was 54.81 ± 3.95 years (range, 37 to 69 years; median, 56 years); seven patients (63.6 percent) were women. Hering dependency was seen in all patients before the external levator advancement. A total of three patients underwent bilateral external levator advancement simultaneously, and eight patients underwent bilateral external levator advancement sequentially. The phenylephrine test was positive in all patients before the Müller muscle-conjunctival resection. Symmetry outcomes were assessed after the revision surgery as perfect (<0.5 mm), good (≥0.5 to <1 mm), or fair (≥1 mm) in four patients, six patients, and one patient, respectively. An optimal correction was noted in 13 of the 22 eyelids after the revision surgery, whereas eight of the 22 eyelids had minimal undercorrection, and one eyelid had minimal overcorrection. Müller muscle-conjunctival resection revision surgery for treatment of the ptotic eyelid following bilateral external levator advancement is viable and may represent a new alternative among the limited revision techniques. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Effects of Ab Interno XEN Gel Implantation on Postural Intraocular Pressure Elevations.

Purpose: The aim of this study was to analyze the postural intraocular pressure (IOP) changes in open-angle glaucoma after ab interno XEN gel implant surgery and to compare them with the changes observed with trabeculectomy and medical treatment.Patients and Methods: The study sample included 18 patients with XEN gel implants, 30 patients who had trabeculectomy, and 30 medically managed glaucoma patients. All patients in XEN gel implant and trabeculectomy groups had at least 11 months of follow-up and had successful surgeries that resulted in medication-free control of IOP. A rebound tonometer (Icare, Finland Oy, Helsinki, Finland) was used to measure the IOP levels at the sitting, supine, and dependent lateral decubitus (DLDP) positions after a 5-minute rest at each position.Results: In all the groups, the mean IOP values in the DLDP and supine positions were significantly higher than the sitting position. The IOP elevation after moving from sitting to supine position was significantly reduced in XEN gel implant and trabeculectomy groups compared to medical treatment group (p = .001 and p = .002, respectively). The IOP elevation after a moving from sitting to DLDP was also significantly reduced in XEN gel implant and trabeculectomy groups compared to the medical treatment group (p = .003 and p = .01, respectively). However, there was no significant difference in IOP change after moving from sitting to supine or DLDP positions between XEN gel implant and trabeculectomy groups (p = .74 and p = .98, respectively).Conclusion: This study demonstrated that XEN gel implant could reduce postural elevations in IOP to the same degree as trabeculectomy and provide significantly better postural IOP control than medical treatment. This surgery can be an effective minimally invasive alternative for patients with significant positional IOP elevations.

Efficacy of Bandage Contact Lenses versus Eye Patching in Early Postoperative Period of Müller's Muscle-Conjunctival Resection.

PURPOSE: Patients with blepharoptosis who are treated with Müller's muscle-conjunctival resection (MMCR) may experience postoperative pain and discomfort related to the suture material on the palpebral conjunctiva. This study aims to compare the postoperative subjective complaints, such as pain and discomfort, with a visual analog scale (VAS), and objectively evaluate the cornea with a tear break-up time (TBUT) test and fluorescein staining following MMCR that was managed by either a bandage contact lens (BCL) or eye patching. METHODS: Forty patients who had undergone a unilateral MMCR were randomized into 2 groups. Group 1 (n = 20) received a BCL, and group 2 (n = 20) received an eye patch following the MMCR. Patients were evaluated postoperatively at 1 and 7 days in this prospective study. The postoperative pain was measured using a VAS, and the requirement for anti-inflammatory medication was analyzed. A slit-lamp examination was performed to evaluate the cornea with a TBUT test and fluorescein staining by objectively using the National Eye Institute (NEI) classification. RESULTS: BCL treatment decreased the VAS score, the need for anti-inflammatory medications, and fluorescein staining using the NEI score and increased the TBUT score significantly compared with the eye patch treatment (p < 0.001). CONCLUSIONS: Our findings suggest that the use of a BCL may be beneficial in terms of reducing early postoperative pain and eye stinging, protecting the cornea, and retaining the ability to perform daily activities following a MMCR.

Analysis of the quality, reliability, and popularity of information on strabismus on YouTube.

To evaluate the quality, reliability, and popularity of YouTube videos addressing strabismus. This is a retrospective, cross-sectional, register-based study. A search was performed using the keywords "strabismus," "squint," "eye squint," and "crossed eye" on YouTube, and the first 50 videos for each keyword were analyzed. The video duration, time since upload, number of total views, view ratio were recorded. Video popularity was recorded using the video power index (VPI). Video educational quality and reliability were measured using the DISCERN questionnaire, Journal of the American Medical Association (JAMA) score, and Global Quality Score (GQS). All videos were also assigned publishers and categories. Among the 200 videos analyzed, 84 were included. The mean duration was 6.2 min, and the mean number of total views was 227,226. The mean VPI score was 189.6 ± 1093.5 (range, 0-11631). The mean DISCERN score, JAMA score, and GQS were 42.2 ± 15.3, 1.9 ± 1.2, and 2.7 ± 1.1, respectively. While the main video publishers were patients (32.1%) and ophthalmologists (28.5%), the main video categories were patient experience (35.7%) and patient information (26.1%). While the most popular videos were uploaded by a TV show/YouTube channel, the videos with the highest educational quality and reliability scores were uploaded by academic institutions. Although some videos contained sufficient information, most of the videos were rated as fair. YouTube users mostly preferred videos that were of low quality. Patients may be receiving biased information, and physicians should be aware of the type of information patients may be accessing on YouTube.