A novel index for predicting intraocular pressure reduction following cataract surgery

Predictive biomarkers of intra-ocular pressure decrease after cataract surgery associated with trabecular washout in patients with pseudo exfoliative glaucoma

To investigate biomarkers of intra-ocular pressure (IOP) decrease after cataract surgery with trabecular washout in pseudo-exfoliative (PEX) glaucoma. A single-center observational prospective study in PEX glaucoma patients undergoing cataract surgery with trabecular washout (Goniowash) was performed from 2018 to 2021. Age, gender, visual acuity, IOP, endothelial cell count, central corneal thickness, medications, were collected over 16-month follow-up. Multivariable binomial regression models were implemented. 54 eyes (35 subjects) were included. Mean preoperative IOP (IOPBL) was 15.9 ± 3.5 mmHg. Postoperative IOP reduction was significant at 1-month and throughout follow-up (p < 0.01, respectively). IOPBL was a predictive biomarker inversely correlated to IOP decrease throughout follow-up (p < 0.001). At 1 and 12 months of follow-up, IOP decrease concerned 31 (57.4%) and 34 (63.0%) eyes with an average IOP decrease of 17.5% (from 17.6 ± 3.1 to 14.3 ± 2.2 mmHg) and 23.0% (from 17.7 ± 2.8 to 13.5 ± 2.6 mmHg), respectively. Performance (AUC) of IOPBL was 0.85 and 0.94 (p < 0.0001, respectively), with IOPBL threshold ≥ 15 mmHg for 82.1% and 96.8% sensitivity, 84.2% and 75.0% specificity, 1.84 and 3.91 IOP decrease odds-ratio, respectively. All PEX glaucoma patients with IOPBL greater than or equal to the average general population IOP were likely to achieve a significant sustainable postoperative IOP decrease.

How much does cataract surgery contribute to intraocular pressure lowering?

PURPOSE OF REVIEW

To review the literature evaluating the effect of cataract surgery on intraocular pressure (IOP) in patients with glaucoma.

RECENT FINDINGS

Recent high-quality secondary analyses of large and primary trials continue to show IOP lowering following cataract surgery. Likewise, cataract surgery remains a key treatment for angle closure glaucoma. Some micro-invasive glaucoma surgeries (MIGS) have strong evidence to be performed at the time of cataract surgery. Data clarifying when these surgeries should be combined with cataract surgery is emerging. The mechanism underlying IOP lowering after cataract surgery remains unclear.

SUMMARY

Patients who are glaucoma suspects with visually significant cataracts would benefit from cataract surgery alone. Those with mild-moderate damage on 1-2 classes of medications would most likely benefit from additional MIGS. Patients with advanced disease would benefit from cataract surgery and a choice of additional surgery, which depends on disease status and patient factors. Clear lens extraction is becoming a more accepted practice as a primary procedure for patients with angle closure and high IOP or glaucoma. The role of additional MIGS in angle closure needs further study.

Anterior Chamber Biometric Parameters Associated With Intraocular Pressure Reduction After Phacoemulsification in Non-Glaucomatous Eyes With Open Angles

BACKGROUND

Decreased intra-ocular pressure after cataract surgery has been reported in eyes with and without glaucoma with variable magnitude. It is influenced by the anatomical structure of the anterior chamber. Preoperative evaluation of anterior chamber parameters can help to predict the change in intra-ocular pressure postoperatively.

OBJECTIVE

The objective of the study is to evaluate intraocular pressure (IOP) change after uneventful phacoemulsification in non-glaucomatous eyes with open angles and its correlation with preoperative anterior chamber parameters measured by anterior segment optical coherence tomography (AS-OCT).

METHODS

In this hospital-based prospective observational study, we included consecutive patients without glaucoma and open angles on gonioscopy who had undergone uncomplicated phacoemulsification with intraocular lens implantation (IOL). IOP and anterior chamber biometric parameters were measured preoperatively and compared with parameters obtained three months post-operatively by AS-OCT. The change in IOP and its relation to the parameters, including anterior chamber angle (ACA), anterior chamber depth (ACD), angle opening distance 500 μm anterior to the scleral spur (AOD500), anterior chamber width (ACW), lens vault (LV), and trabecular iris space area (TISA500) were evaluated. The main outcome measure was a change in IOP after phacoemulsification in normal eyes.

RESULTS

Sixty-four eyes of 64 patients were enrolled. The mean patient age was 58.5 ± 9.4 years. The average IOP reduction was 2.43±1.64 mm of Hg from a preoperative mean of 16.77±2.54 mmHg three months after phacoemulsification surgery. The mean AOD500 increased significantly (0.440 ± 0.07 to 0.522 ±0.092) from preoperatively to three months postoperatively (p < 0.001). Preoperative lens vault and preoperative IOP had a strong positive correlation with the change in IOP at three months (r-value = 0.606; p-value <0.001) and (r-value = 0.73; p-value <0.001). There was a significant negative correlation between pre-operative TISA and AOD with change in IOP at three months (r-value = -0.545; p-value <0.001) and (r-value = -0.69; p-value <0.01).

CONCLUSION

 Phacoemulsification surgery results in IOP reduction in non-glaucomatous eyes. Pre-operative IOP, lens vault, AOD, and TISA were significant predictors for IOP reduction.

The effect of baseline intraocular pressure and anterior segment parameters on intraocular pressure after intravitreal bevacizumab injection

PURPOSE

We aimed to compare the predictive effect of pre-injection intraocular pressure (IOP) and anterior segment parameters on post-injection IOP values after intravitreal bevacizumab injection for neovascular age-related macular degeneration (NVAMD) in phakic and pseudophakic patient groups.

MATERIAL AND METHODS

This retrospective cross-sectional study included 65 eyes of 65 treatment-naive NVAMD patients. Patients were divided into two groups according to their lens status (35 phakic and 30 pseudophakic patients). Pre-injection IOP, anterior segment parameters measured with PENTACAM, and post-injection IOP values measured at the 5th minute were recorded. Univariate and multivariate regression analyses were used to recognise the predictive effect of pre-injection IOP and anterior segment parameters on post-injection IOP for each group.

RESULTS

Multivariate regression analyses showed that the decrease in anterior chamber depth (ACD), and the increase in pre-injection IOP were significantly correlated with higher post-injection IOP in the phakic patient group (p = 0.019 and 0.031; respectively). No correlation was found in the pseudophakic patient group.

CONCLUSION

Pre-injection ACD and IOP values may be predictive of higher post-injection IOP in phakic patients. Preoperative assessment of these parameters could be beneficial in patients at risk of glaucoma.

Hemi-GATT combined with phacoemulsification in patients with moderate-severe primary open-angle glaucoma: 2-year outcomes

PURPOSE

To describe the outcomes of inferior hemisphere 180° gonioscopy-assisted transluminal trabeculotomy (hemi-GATT) in patients with moderate-severe stage primary open-angle glaucoma (POAG).

METHODS

This single center, retrospective study identified patients with POAG who had undergone combined inferior hemi-GATT with phacoemulsification. Patients with moderate-severe staged POAG were included in the study. Outcome measures included surgical success, intraocular pressure (IOP), number of topical IOP-lowering drops, best-corrected visual acuity (BCVA), visual field mean deviation (MD) and complications. Success was defined using two criteria: Criterion A (IOP <17 mmHg and >20% reduction) and Criterion B (IOP <12 mmHg and >20% reduction).

RESULTS

One hundred-twelve eyes of 112 patients were included in this study. Of these, 91 patients were followed for 24 months or greater to assess endpoint surgical success. Kaplan-Meier survival analysis for Criterion A demonstrated a 64.8% probability of success without topical IOP-lowering therapy (complete success) and a 93.4% probability of success with or without topical IOP-lowering therapy (qualified success). Probabilities of complete and qualified success using Criterion B were 26.4% and 30.8%, respectively. IOP reduction from baseline (21.9 ± 5.8 mmHg) to 24-month follow-up (13.6 ± 3.9 mmHg) was 37.9% for the overall cohort. The most common complication was transient hyphema, which occurred in 25.9% (29 of 112) of patients. All cases of hyphema resolved spontaneously.

CONCLUSIONS

Combined hemi-GATT with phacoemulsification was associated with favorable outcomes and a low complication rate in this study of patients with moderate-severe POAG. Further studies are required comparing hemi-GATT to the 360° approach.

Predictors of long-term intraocular pressure control after lens extraction in primary angle closure glaucoma: results from the EAGLE trial

BACKGROUND/AIMS

To assess baseline ocular parameters in the prediction of long-term intraocular pressure (IOP) control after clear lens extraction (CLE) or laser peripheral iridotomy (LPI) in patients with primary angle closure (PAC) disease using data from the Effectiveness of Early Lens Extraction for the treatment of primary angle-closure glaucoma (EAGLE) tria.

METHODS

This study is a secondary analysis of EAGLE data where we define the primary outcome of 'good responders' as those with IOP<21 mm Hg without requiring additional surgery and 'optimal responders' as those who in addition were medication free, at 36-month follow-up. Primary analysis was conducted using a multivariate logistic regression model to assess how randomised interventions and ocular parameters predict treatment response.

RESULTS

A total of 369 patients (182 in CLE arm and 187 in LPI arm) completed the 36-month follow-up examination. After CLE, 90% met our predefined 'good response' criterion compared with 67% in the LPI arm, and 66% met 'optimal response' criterion compared with 18% in the LPI arm, with significantly longer drops/surgery-free survival time (p<0.05 for all). Patients randomised to CLE (OR=10.1 (6.1 to 16.8)), Chinese (OR=2.3 (1.3 to 3.9)), and those who had not previously used glaucoma drops (OR=2.8 (1.6 to 4.8)) were more likely to maintain long-term optimal IOP response over 36 months.

CONCLUSION

Patients with primary angle closure glaucoma/PAC are 10 times more likely to maintain drop-free good IOP control with initial CLE surgery than LPI. Non-Chinese ethnicity, higher baseline IOP and using glaucoma drops prior to randomisation are predictors of worse long-term IOP response.

Changes in anterior chamber biometry and intraocular pressure after uneventful phacoemulsification in non-glaucomatous eyes

Background

In non-glaucomatous eyes, many factors impact intraocular pressure (IOP) reduction following phacoemulsification. This study aimed to determine the relationship between changes in IOP and alterations in anterior chamber biometric measurements using the Pentacam Scheimpflug anterior segment imaging system before and after uneventful phacoemulsification in non-glaucomatous eyes.

Methods

This prospective interventional study included patients with ages of 20 - 80 years, no known systemic diseases, and visually significant cataracts necessitating phacoemulsification with posterior chamber intraocular lens implantation. The preoperative and two-month postoperative IOPs were measured using a Goldmann applanation tonometer, and the iridocorneal angle (ICA) in four quadrants (superior, inferior, nasal, and temporal), anterior chamber depth (ACD), and anterior chamber volume (ACV) were measured using the Pentacam.

Results

Forty-two eyes of 42 patients with a mean (standard deviation [SD]) age of 56.8 (10.7) years were included; 22 (52%) were men and 20 (48%) were women. The eyes demonstrated statistically significant changes in postoperative IOP, ACD, ACV, and in widening of the ICA (all P < 0.05), with a mean (SD) IOP reduction of 4.5 (2.7) mmHg, ACD deepening of 0.7 (0.6) mm, ACV increase of 33.2 (21.1) mm3, and ICA widening of 7.5o (6.4o), 12.4o (7.7o), 9.1o (7.1o), and 11.5o (6.1o) in the superior, inferior, temporal, and nasal quadrants, respectively. A significant positive correlation was detected between pre- and postoperative IOP (r = + 0.58; P < 0.001) and between pre- and postoperative ACD (r = + 0.50; P < 0.001). Significant negative correlations were detected between preoperative ACV and changes in ACV (r = - 0.42; P < 0.001) and between preoperative ICA and changes in ICA (r = - 0.02; P = 0.001). However, no significant correlations were observed between the changes in IOP and patient age (r = + 0.001; P = 0.957) and axial length of the eye (r = + 0.13; P = 0.221), or changes in ICA (r = - 0.01; P = 0.945), ACD (r = + 0.01; P = 0.945), and ACV (r = - 0.12; P = 0.599).

Conclusions

We observed a significant reduction in IOP, widening of the ICA, and increases in ACD and ACV after phacoemulsification; however, there was no significant correlation between changes in IOP and other biometric variables. Further studies are required to determine the exact mechanisms underlying these effects.

Changes in Anterior Segment Morphology and Intraocular Pressure after Cataract Surgery in Non-glaucomatous Eyes

BACKGROUND

It is known that cataract extraction is associated with a significant reduction in intraocular pressure, especially in narrow angled eyes; however, the modifications of anterior segment parameters associated with this phenomenon have still not been completely defined. The purpose of this study was to evaluate changes in anterior segment anatomy and intraocular pressure after cataract surgery in non-glaucomatous eyes.

METHODS AND MATERIAL

This retrospective case series study included 64 eyes of 64 consecutive patients who underwent phacoemulsification with intraocular lens implantation. Anterior segment parameters and intraocular pressure were assessed and compared before and 6 months after surgery. Anterior segment imaging was performed using Casia SS-1000 anterior segment optical coherence tomography (Tomey, Nagoya, Japan). Anterior segment measurements included anterior chamber depth, anterior chamber width, anterior chamber volume, angle opening distance at 500 µm anterior to the scleral spur, angle recess area 750 µm from the scleral spur, lens vault, trabecular iris space area at 500 µm from the scleral spur, and trabecular iris angle at 500 µm from the scleral spur. Intraocular pressure was measured using the Goldmann applanation tonometer (Model AT 900 C/M, Haag-Streit, Bern, Switzerland). Anterior segment parameters and the relationship of changes in intraocular pressure were also evaluated.

RESULTS

All anterior segment parameters increased significantly after surgery (p < 0.05). Both angle opening distance at 500 µm anterior to the scleral spur and anterior chamber depth changes were positively correlated with the preoperative lens vault. The mean intraocular pressure significantly decreased from 14.91 mmHg (± 2.8 SD) to 12.91 mmHg (± 3.13 SD) (p < 0.001). Changes in intraocular pressure correlated negatively with values for the width of the preoperative anterior chamber (r = - 0.533; p = 0.001).

CONCLUSION

Cataract surgery led to significant widening of the anterior chamber angle and lowering of intraocular pressure. Further investigations are needed to better understand whether anterior chamber width may be a new independent predictive factor for reduction in postoperative intraocular pressure.

Femtosecond Laser-assisted Cataract Surgery in Patients With Prior Glaucoma Surgery

PRCIS

Femtosecond laser-assisted cataract surgery (FLACS) is a safe procedure in glaucomatous eyes with prior glaucoma surgery, evidenced by stable intraocular pressure (IOP) and medication use, acceptable success rate, disease stability, and low complication rates at 1-year postoperative.

PURPOSE

The purpose of this study was to assess the 1-year efficacy and safety of FLACS in glaucomatous eyes with prior glaucoma surgery.

MATERIALS AND METHODS

Retrospective case series of all consecutive glaucomatous eyes with previous glaucoma surgery that underwent FLACS using the Catalys Precision Laser System with or without concomitant glaucoma surgery at a single ophthalmology center, between 2014 and 2020. Efficacy included change in IOP, glaucoma medication use, best-corrected visual acuity, and surgical success at 12 months postoperatively (POM12). Safety included structural and functional measures of disease stability and postoperative adverse events.

RESULTS

A total of 57 eyes with an average age of 62.6±8.1 years were included. At POM12, IOP decreased from 14.5±6.6 mmHg to 13.5±3.7 mm Hg (P=0.22) and glaucoma medication use decreased from 2.1±1.5 to 1.8±1.4 with a marginal significance (P=0.089). Best-corrected visual acuity improved significantly in both groups (P<0.001) and surgical success ranged between 74% and 90% according to the study's success criteria. Safety was favorable with disease stability evidenced by lack of deterioration in cup-to-disc ratio, visual field mean deviation, retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness. One eye with prior history of trabeculectomy experienced transient bleb leak. Other adverse events were minor without sight-threatening sequelae.

CONCLUSIONS

The results of this study suggest that FLACS with or without concomitant glaucoma surgery could be a safe procedure in glaucomatous eyes-a population for which FLACS has been relatively contraindicated. Nonetheless, in those with preexisting filtering bleb, extra attention should be paid to the bleb area.

Gonioscopy-assisted Transluminal Trabeculotomy (GATT) combined phacoemulsification surgery: Outcomes at a 2-year follow-up

BACKGROUND/OBJECTIVES

This study aimed to provide a 24-month follow-up on the surgical success and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) combined with phacoemulsification and intraocular lens (IOL) implantation in the treatment of patients with primary open-angle glaucoma (POAG) combined cataract.

SUBJECTS/METHODS

We included 124 consecutive cases of POAG with microcatheter-assisted GATT or GATT combined with phacoemulsification and IOL implantation at Beijing Tongren Eye Centre between October 2019 and November 2020. Main outcome measures included surgical success rate, changes in IOP, number of antiglaucoma medications, best corrected visual acuity (BCVA), postoperative complications at baseline, and follow-up period of up to 24 months.

RESULTS

In total, 58 eyes received GATT combined with phacoemulsification surgery and 66 eyes received GATT alone. The overall qualified success rate was 86.21% for eyes with GATT combined with phacoemulsification surgery, and 83.48% for eyes with GATT only at 24 months. IOP was reduced from 26.40 ± 6.37 mmHg on 3.12 ± 0.80 medications preoperatively to 14.61 ± 2.28 mmHg on 0.27 ± 0.71 medications at 12 months and 16.08 ± 2.38 mmHg on 0.45 ± 0.96 medications at 24 months after combined surgery. Additionally, mean BCVA improved from 0.75 ± 0.43 logMAR units preoperatively to 0.22 ± 0.18 logMAR units 24 months after combined surgery. No vision-threatening complications occurred during the 24-month follow-up.

CONCLUSIONS

The 24-month follow-up results of our study suggest that GATT combined with cataract surgery is a safe and effective treatment for decreasing IOP and number of medications in patients with POAG combined cataract.

Predictors of intraocular pressure change after cataract surgery in patients with pseudoexfoliation glaucoma and in nonglaucomatous patients

Background/Aim. The cataract surgery in eyes with and without glaucoma results in the sustained intraocular pressure (IOP) reduction but it is still unknown which glaucomatous patients will achieve clinically significant reduction. The preoperative IOP and some ocular biometric parameters have been shown as potential predictors of the postoperative IOP reduction. The aim of our prospective intervention study was to evaluate that relationship in medically controlled patients with the pseudoexfoliation glaucoma (PXG) and in the nonglaucomatous patients. Methods. Thirty-one PXG patients (31 eyes) and 31 nonglaucomatous patients (31 eyes), all with clinically significant cataract, were enrolled. The preoperative IOP, anterior chamber depth (ACD), axial length (AL), lens thickness (LT), lens position (LP) [LP = ACD + 0.5 LT], relative lens position (RLP) [RLP = LP / AL] and the pressure-to-depth ratio (PD ratio) [PD ratio = preoperative IOP/preoperative ACD] were evaluated as potential predictors of the IOP change in the 6th postoperative month. Results. In the 6th postoperative month, in the PXG group, the IOP reduction was -3.23 ? 3.41 mmHg (-17.67 ? 16.86%) from the preoperative value of 16.27 ? 3.08 mmHg and in the control group, the reduction was -2.26 ? 1.71 mmHg (-15.06 ? 10.93%) from the preoperative value of 14.53 ? 2.04 mmHg. In the PXG group, the significant predictors of the absolute and the percentage IOP reduction were the preoperative IOP, AL, and PD ratio. In the same group, RLP was shown as a significant predictor of absolute change in the IOP in multi-variate analysis, and the percentage IOP change in both the univariate and the multivariate analyses. In the control group, the preoperative IOP and the PD ratio were the only significant parameters that could predict absolute change in the postoperative IOP. Conclusion. The cataract surgery leads to the IOP reduction both in the PXG and nonglaucomatous eye. Predictors monitored in this study are widely available and simply calculable parameters that can be potentially used in managing glaucoma.

Nasal trabeculo-ciliary angle and relative lens vault as predictors for intraocular pressure reduction following phacoemulsification

PURPOSE

To evaluate quantitative relationships between biometric measurements and expected intraocular pressure reduction following phacoemulsification.

DESIGN

A prospective, comparative clinical study.

METHODS

Forty nine candidates for phacoemulsification were included. Intraocular pressure was measured preoperatively and after 7 and 30 days. Ocular biometrics were measured using optical biometry and ultrasound biomicroscopy preoperatively and 1 month postoperatively.

RESULTS

Patients were sub-grouped into open-angle glaucoma (12 eyes), angle-closure glaucoma (18 eyes), and cataract-only groups (19 eyes). The mean intraocular pressure reduction was -1.67 ± 2.73, -13.11 ± 7.98, and -7.50 ± 3.58 mmHg in the cataract-only, angle-closure glaucoma, and open-angle glaucoma groups (p = 0.001). The delta-intraocular pressure at day 7 showed positive correlations with lens vault and relative-lens vault (p = 0.005 and 0.001). It showed negative correlations with lens position, relative-lens position, anterior chamber depth, aqueous depth, and nasal and temporal angles in addition to lens thickness, anterior vault, nasal trabeculo-ciliary angle, and temporal-trabeculo-ciliary angle at the end of the follow-up period. Regression analysis revealed significant associations between preoperative intraocular pressure and both nasal-trabeculo-ciliary angle and anterior vault (p = 0.038 and 0.019) and delta-intraocular pressure and both nasal-trabeculo-ciliary angle and relative-lens vault (p = 0.001 and ≤0.001) with an area under the curve of 0.71 for relative-lens vault. For every degree decrease in nasal-trabeculo-ciliary angle, there was an expected 0.33 mmHg intraocular pressure reduction with no expected change if nasal-trabeculo-ciliary angle decreased to <22°.

CONCLUSIONS

The relationship between anterior-segment-biometrics could determine intraocular pressure behavior after phacoemulsification. The preoperative nasal-trabeculo-ciliary angle and relative-lens vault could be significant predictors for postoperative intraocular pressure reduction.

Intraocular pressure changes after phacoemulsification in pseudoexfoliation versus healthy eyes

Background

Pseudoexfoliation (PXF) syndrome is the most common cause of secondary glaucoma worldwide. This systemic disorder causes further damage to the optic nerve and ultimately increases the need for surgical interventions. Therefore, intraocular pressure (IOP) control is very important in these patients. The aim of this study was to compare IOP changes after phacoemulsification in subjects with PXF syndrome compared to those without this syndrome.

Methods

61 patients were enrolled in this prospective clinical study. Subjects were assigned into two groups based on presence or absence of PXF syndrome. IOP and anterior chamber angle parameters including: angle opening distance (AOD) and trabecular-iris surface area (TISA) measured one day preoperatively and 3 months postoperatively. Intraoperative metrics factors including: infusion fluid usage (IFU), cumulative dissipated energy (CDE) and aspiration time (AT) were obtained from the phacoemulsification machine at the end of each surgery. IOP changes, anterior chamber angle parameters and intraoperative metrics factors were compared between groups.

Results

Mean IOP before surgery was significantly higher in the PXF group (14.70 mm Hg) compared to controls (12.87 mm Hg) (P-value < 0.01). Phacoemulsification decreased IOP in both, but to greater extent in the PXF group (p-value < 0.01). AOD and TISA also increased significantly following surgery in both groups. The results showed that postoperative IOP was negatively correlated with preoperative IOP in both groups (p-value < 0.01). Also, IOP after phacoemulsification was negatively correlated with IFU in the PXF group (p-value = 0.03).

Conclusions

Patients with PXF syndrome exhibited a reduction in IOP and increase in anterior chamber angle parameters after phacoemulsification. We observed a greater IOP reduction in PXF subjects when it was compared to controls. Higher preoperative IOP and intraoperative IFU were associated with more IOP reduction in the PXF group.

Intraocular Pressure Reduction after Femtolaser Assisted Cataract Surgery and Its Association with the Use of Ultrasound

Background and Objectives: To quantify the change in intraocular pressure (IOP) after phacoemulsification in patients having undergone femtolaser assisted cataract surgery (FLACS), and study the influence of the use of ultrasound on this change. Setting: Jules-Gonin Eye Hospital, University Department of Ophthalmology, Lausanne, Switzerland. Materials and Methods: Interventional study. Methods: All consecutive cases operated with FLACS and with complete data for the studied parameters were selected for inclusion in the study. Data had been prospectively collected and was analysed retrospectively. Linear regression was performed to explore the association of change in IOP with time of measure, ultrasound use, sex, age, and duration of surgery. Results: There was a mean decrease in intraocular pressure of 2.5 mmHg (CI 95% −3.6; −1.4, p < 0.001) postoperatively. No association between the change in intraocular pressure and ultrasound time or effective phaco time was observed when the data were analyzed one at a time or in a multiple linear regression model. There was no association with sex, age, nuclear density, presence of pseudoexfoliation, duration of surgery, and time of ocular pressure measurement. Eyes with preoperative IOP ≥ 21 mmHg had a more significant IOP reduction after surgery (p < 0.0001) as did eyes with an anterior chamber depth <2.5 mm (p = 0.01). Conclusion: There was a decrease in intraocular pressure six months after FLACS in our study similar to that in the published literature for standard phacoemulsification. The use of ultrasound may not influence the size of the decrease, whereas the preoperative IOP and anterior chamber depth do. FLACS may be as valuable as standard phacoemulsification for cases where IOP reduction is needed postoperatively.

Surgical and Perioperative Considerations for the Treatment of Cataract in Eyes with Glaucoma: A Literature Review

Cataract surgery in the presence of glaucoma poses certain challenges that need to be addressed to offer the maximum benefit without complications. In this paper, we are reviewing the preoperative assessment, surgical options, the planning, and postoperative care. Cataract surgery can help reduce the intraocular pressure alone or combined with MIGS. When performed in patients with glaucoma, it can transiently increase the intraocular pressure and later on decrease the IOP to levels lower than the postoperative. The preoperative IOP and biometric characteristics are the main predictors of the postoperative course of IOP. The combination of cataract surgery with trabeculectomy remains controversial, in terms of best timing of each operation.

Laser flare and cell photometry to measure inflammation after cataract surgery: a tool to predict the risk of cystoid macular edema

PURPOSE

To review the current adoption of laser flare and cell photometry (LFCP) in the setting of modern cataract surgery to analyze inflammation aiming to identify evidence of a correlation between LFCP values and the risk of cystoid macular edema (CME) development.

METHODS

An extensive PubMed literature search was performed to review all the published studies investigating inflammation by LFCP after uncomplicated phacoemulsification. The following keywords were used: cataract surgery, cystoid macular edema, anterior chamber inflammation, laser flare, and cell photometry.

RESULTS

Seventy-eight original articles investigating inflammation by LFCP were selected. Macula alterations were searched in 12 (15%) trials, by optical coherence tomography or fluorescein angiography in 11 (14%) and 1 (1%) studies, respectively. Among them, 9 (12%) papers investigated the correlation between LFCP values and cystic changes to the macula: 7 (9%) and 2 (3%) studies identified a positive and negative correlation, respectively. Three (4%) papers did not perform any correlation analysis.

CONCLUSION

CME, as a consequence of uncontrolled postoperative inflammation, is a common cause for unfavorable visual outcomes following uncomplicated phacoemulsification with IOL implantation. After surgery, intraocular inflammation is generally assessed by qualitative methods. Although well-established and practical in uveitis, they are inadequate to detect the modest inflammatory response that usually occurs after uneventful phacoemulsification. LFCP correlate with the chance of macula alteration after surgery and higher the values higher the risk of CME. The quantitative analysis of intraocular inflammation by LFCP after cataract surgery might be a tool to predict the risk of pseudophakic CME.

Persistence of Inflammation After Uncomplicated Cataract Surgery: A 6-Month Laser Flare Photometry Analysis

PURPOSE

To evaluate, by laser photometry, the persistency of anterior chamber flare after uneventful phacoemulsification in asymptomatic patients with no signs of inflammation on slit lamp examination.

METHOD

Seventy-five patients previously enrolled in a randomized clinical trial that evaluated inflammation after uneventful phacoemulsification in eyes treated with dexamethasone 0.1% ophthalmic suspension (group 1) or bromfenac 0.09% ophthalmic solution (group 2) for 2 weeks. Anterior chamber inflammation was investigated by laser flare photometry. At 30 days after surgery, laser flare showed persistently elevated values. For this reason, patients were further analyzed at 3 and 6 months. Additionally, optical coherence tomography was used to measure the central macular thickness (CMT) and to assess for postoperative pseudophakic macular edema.

RESULTS

When compared to preoperative values, laser flare photometry demonstrated persistent ocular inflammation at postoperative days 90 and 180 in group 1, but not in group 2. Laser flare values showed a significant reduction in group 2 compared to group 1 throughout all the follow-up (p < 0.001). The increase in mean CMT at days 90 and 180 with respect to baseline was statistically significant in group 1 but not in group 2, in which it decreased to levels similar to preoperative value. Group 1 showed a higher increase in mean CMT compared to group 2 throughout all the follow-up (p < 0.001). The proportion of patients that developed pseudophakic cystoid macular edema (CME) was 14% (n = 5) and 0% (n = 0) in group 1 and group 2, respectively (p = 0.02). The bivariate analysis demonstrated a positive correlation between laser flare and CMT values in group 1 but not in group 2.

CONCLUSION

Anterior chamber inflammation persists for more than 30 days in a significant proportion of patients after uncomplicated cataract surgery and may be responsible for late onset of cystoid macular edema cases.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03317847.

Predictive factors for the IOP reduction in phacocanaloplasty with suprachoroidal drainage

PURPOSE

Although the pressure-reducing effect of cataract surgery alone is not very high, it is often cited in the literature. Some authors describe predictive factors correlated with the IOP (intraocular pressure) reduction: in particular noteworthy are age, axial length, preoperative pressure level and the ratio of preoperative pressure/anterior chamber depth. The aim of this study was to determine the applicability of these predictive factors to phacocanaloplasty with suprachoroidal drainage. Setting Eye Clinic Sulzbach Germany.

DESIGN

Retrospective study with a 12-month follow-up, including patients that underwent phacocanaloplasty with suprachoroidal drainage between 2012 and 2014.

METHODS

Preoperatively, baseline information was collected (including age, diagnosis, medication), and the patients underwent a basic examination and optical biometry. To investigate the relationship between preoperative parameters and the IOP reduction, Pearson's correlation analysis and linear regression were used. Patients with missing data pre- or postoperatively were excluded from the analysis.

RESULTS

The study comprised 89 patients. Mean preoperative IOP was 23.0 ± 5.3 mmHg with 4.0 different antiglaucomatous eye drops. After 12 months, IOP was reduced to 12.1 ± 1.4 mmHg with a median medication of 0.0. The preoperative IOP and the ratio of preoperative IOP/anterior chamber depth were identified as predictive factors. There was no influence of axial length and anterior chamber depth.

CONCLUSION

Unlike in cataract surgery, anterior chamber depth and axial length have no influence on the pressure reduction caused by phacocanaloplasty. However, a strong predictive factor is the preoperative pressure level. The higher the preoperative IOP, the greater the postoperative pressure reduction.

Effect of Preoperative Factor on Intraocular Pressure after Phacoemulsification in Primary Open-angle Glaucoma and Primary Angle-closure Glaucoma

Purpose

To compare the effects of cataract surgery on intraocular pressure (IOP) according to preoperative factor in primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG).

Methods

The medical records of 75 POAG and 95 PACG patients who underwent cataract surgery were reviewed. We classified POAG patients with a preoperative peak IOP of less than 31 mmHg and less than three medications used before surgery and PACG patients with a peak IOP of less than 42 mmHg, less than three medications used, and peripheral anterior synechiae of less than four clock hours into group 1. Patients with levels exceeding these thresholds were classified into group 2. The IOP, numbers of medications, and success rates were compared between two groups.

Results

At 36 months after surgery, IOP reduction in group 1 was significantly greater than that in group 2 among POAG patients (−1.7 ± 2.1 vs. −0.6 ± 2.0 mmHg, p = 0.021); however, there was no significant difference between the two groups for PACG patients (−2.5 ± 2.0 vs. −2.2 ± 3.3 mmHg, p = 0.755). The medication changes were similar between the two groups for both POAG and PACG patients. The success rate at 36 months was significantly higher in group 1 than in group 2 for POAG patients (66.7% vs. 35.7%, p = 0.009), but there was no significant difference between the two groups for PACG patients (79.1% vs. 69.2%, p = 0.264).

Conclusions

For patients with relatively low peak IOP who used fewer medications before surgery, cataract surgery alone was effective for IOP control in both POAG and PACG patients. Conversely, For POAG patients with a history of higher peak IOP and who used more medications, cataract surgery was not effective in lowering IOP, whereas it resulted in relatively good IOP values in PACG patients.

Pneumotonometer Accuracy Using Manometric Measurements after Radial Keratotomy, Clear Corneal Incisions and Lamellar Dissection in Porcine Eyes

Purpose/Aim of the study: Measured intraocular pressure (IOP) after corneal incisions may not be reflective of the true IOP because of changes in corneal biomechanical properties. The purpose of this study is to investigate the effect of various corneal incisions on pneumotonometer accuracy in enucleated porcine eyes.Materials and Methods: A pneumotonometer was used to measure IOP (IOPp) at manometrically controlled pressure levels of 10, 20, 30 and 40 mmHg in enucleated porcine eyes. IOP measurements at each level were repeated after one of the following corneal incisions: radial keratotomy (8 eyes), lamellar dissection (10 eyes), clear cornea standard phacoemulsification incisions (10 eyes). The pneumotonometer error, defined as the difference between IOPp and manometric pressure (IOPm), was calculated for each pressure level. The error before the corneal incisions was compared to the error after the corneal incisions to assess the accuracy of the pneumotonometer.Results: The pneumotonometer underestimates true IOP at all pressure levels, both before and after the corneal procedures. There was a statistically significant greater underestimation of IOP after radial keratotomy incisions at pressure levels of 20, 30 and 40 mmHg (p = .013, 0.004, and 0.002, respectively). There was no statistically significant difference in the amount of pneumotonometer underestimation error after lamellar dissection or standard cataract incisions.Conclusion: The pneumotonometer underestimates true IOP in enucleated porcine eyes at all pressure levels between 10-40 mmHg. Radial keratotomy incisions caused a statistically significant greater underestimation error in pneumotonometry measurements at pressures of 20-40 mmHg. Lamellar dissection and clear corneal cataract incisions did not cause an additional error in pneumotonometry measurements in enucleated porcine eyes.

Intraocular Pressure and Anterior Segment Morphometry Changes after Uneventful Phacoemulsification in Type 2 Diabetic and Nondiabetic Patients

Purpose

To compare intraocular pressure (IOP) and anterior segment (AS) morphometry changes after uneventful phacoemulsification between nonglaucomatous eyes with open-angles from patients with and without type 2 diabetes mellitus (DM) and determine which factors may predict greater IOP-lowering effect.

Methods

Forty-five diabetic (45 eyes) and 44 (44 eyes) age- and sex-matched non-DM patients with age-related cataract were enrolled in this prospective observational study. Goldmann applanation tonometry and AS Scheimpflug tomography (Pentacam® HR) were performed preoperatively and at 1- and 6-month follow-up. Linear regression analysis was performed to evaluate the clinical variables related to postoperative IOP changes at 6 months.

Results

There was a significant postoperative IOP reduction 6 months after surgery (p < 0.001) by an average of 2.9 ± 2.9 mmHg (15.5%) and 2.4 ± 2.8 mmHg (13.0%) in the DM group and non-DM groups (p = 0.410), respectively. All AS parameters (anterior chamber depth, volume, and angle) increased significantly postoperatively (p < 0.001). Multivariate linear regression analysis showed that higher preoperative IOP was significantly associated with IOP reduction at 6-month follow-up (p < 0.05).

Conclusion

Nonglaucomatous eyes with open-angles from both type 2 diabetic and nondiabetic patients experienced similar AS changes and IOP reductions following uneventful phacoemulsification, and this IOP-lowering effect was strongly correlated with preoperative IOP.

How to Predict Intraocular Pressure Reduction after Cataract Surgery? A Prospective Study

Purpose/Aim: To evaluate the best formula to predict intraocular pressure (IOP) reduction after cataract surgery. Materials and methods: In this prospective longitudinal study, we included consecutive patients with or without glaucoma, either with open or with narrow angles but without peripheral anterior synechiae, who underwent phacoemulsification. Clinical factors and anterior segment parameters measured with optical biometry and optical coherence tomography were evaluated as preoperative predictors for IOP reduction at 6 months postoperatively. To find the best combinations of predictors, model selection was conducted using least absolute selection and shrinkage operator regression with cross-validation. Results: A total of 156 eyes from 109 patients were enrolled. The mean age of the patients was 74.89 (±8.54) years and the average preoperative IOP was 15.6 (±3.68) mmHg with 0.7 (range 0-4) glaucoma medications. The mean IOP reduction after phaco was 3.1 (±2.49) mmHg at postoperative month 6. After multivariate analysis, preoperative IOP (β = 0.49 [0.4-0.59] P < .0001), gonioscopy score (β = -0.14 [-0.23 to -0.06] P = .0001), anterior chamber depth (β = -0.85 [-1.64 to -0.07] P = 0.033), lens thickness (LT) (β = 0.87 [0.12-1.62] P = .024), and angle open distance 750 (β = -2.2 [-3.96 to -0.44] P = 0.014) were associated with IOP reduction. The best formula to correlate with IOP reduction was -4.76 + (0.46 × preoperative IOP) - (0.42 × LT) - (0.1 × gonioscopy score) - (0.66 × glaucoma status). Conclusion: Different formulas were developed and were able to improve the predictive value of the preoperative IOP. When used in combination, these formulas may help the clinician to know how much IOP reduction to expect after cataract surgery at 6 months postoperatively.

Intraocular Pressure (IOP) Change and Frequency of IOP Spike After Cataract Surgery in Normal-tension Glaucoma: A Case-Control Study

PURPOSE

To evaluate the early-postoperative intraocular pressure (IOP) changes and frequency of IOP spike after cataract surgery in normal-tension glaucoma (NTG) eyes and to compare them with those of nonglaucomatous eyes.

MATERIALS AND METHODS

This was a case-control study. We reviewed the medical records of patients who had undergone cataract surgery. One-to-one (1:1) case matching was performed, each matched set consisting of 1 NTG and 1 nonglaucomatous eye as the control eye. Comparisons between those 2 groups were performed. Specifically, IOP was measured preoperatively and 1 day, 1, 2, and 4 weeks postoperatively. The incidence of IOP spike was evaluated according to the criteria of IOP higher than 21, 25, 30 mm Hg, higher than 5, 10 mm Hg over baseline IOP, and 50% above preoperative IOP.

RESULTS

A total of 298 eyes (149 NTG eyes and 149 control eyes) were enrolled. Preoperative IOP did not show any significant difference between the 2 groups (P=0.687). IOP significantly decreased in both the NTG and control groups [P<0.001, repeated-measures analysis of variance (ANOVA)]. No significant differences in this regard were detected between the 2 groups (P=0.618, repeated-measures ANOVA). When IOP spike was evaluated according to the 6 criteria, the frequencies were <3% at any timepoint. There was no significant difference between the 2 groups.

CONCLUSIONS

In both the NTG and control groups, IOP gradually decreased in the early-postoperative period after cataract surgery, and there was no significant difference between the 2 groups. The frequency of IOP spike was <5% in both the NTG group and the control group.

Post-phacoemulsification iris changes in eyes with glaucoma or glaucoma suspect status

Purpose

This prospective study used anterior segment optical coherence tomography (AS-OCT) to determine how phacoemulsification (phaco) changes iris parameters in eyes with glaucoma or glaucoma suspect status.

Methods

Using Visante AS-OCT (Carl Zeiss Meditec AG), the following pre- and post-phaco parameters were measured: IT750 = iris thickness at 750 μm from the scleral spur; IT2000 = iris thickness 2000 μm from the scleral spur; ITCM = the maximum iris thickness at the middle one third of the iris; ICURV = iris curvature; IAREA = iris area; and pupil size = pupil diameter (mm). Only high-quality images with an identifiable scleral spur were included, and only the nasal quadrant was analyzed. A single glaucoma specialist analyzed the parameters according to the Zhongshan Angle Assessment Program (ZAAP, Guangzhou, China). Multivariate analysis was performed using mixed effects regression correcting for age, gender, and ethnicity.

Results

89 subjects and 110 eyes were included in this study. The mean age of subjects was 74.83 {+/-} 8.69 years old. Most common diagnoses were POAG and glaucoma suspect (23% and 52%, respectively), and 16% of subjects had an LPI. In multivariate analysis of AS-OCT parameters, decreases in IT750, IT2000, ITCM, ICURV, and pupil size were statistically significant (p<0.05).

Conclusions

After phacoemulsification, eyes with glaucoma as well as glaucoma suspect eyes have thinner irises and smaller pupils. This may lead to less iris-mediated aqueous outflow obstruction, providing support for early phacoemulsification glaucoma treatment.

Translational relevance

Our AS-OCT imaging findings may guide clinical practice as iris parameters become increasingly relevant in preoperative phaco planning.

Glaucoma severity and intraocular pressure reduction after cataract surgery in eyes with medically controlled glaucoma

To investigate the relationship between glaucoma severity and intraocular pressure (IOP) reduction after cataract surgery in patients with medically controlled primary open-angle glaucoma (POAG).Retrospective case series.This study included glaucoma suspects (GS) and POAG patients who underwent cataract surgery and continued to use the same glaucoma medications during the postoperative period of 4 months. The main outcomes were percent and absolute IOP changes calculated using the preoperative IOP and the postoperative IOP at 3 months. Preoperative glaucoma medications, preoperative IOP, demographic information, biometric parameters and variables for glaucoma severity were evaluated as potential predictors of IOP change.The average IOP reduction was 3.3 ± 2.4 mmHg (20.0%) and 2.2 ± 2.5 mmHg (13.1%) from the preoperative mean of 16.0 ± 2.9 mmHg and 15.2 ± 3.3 mmHg in the GS and POAG groups, respectively. Preoperative IOP, preoperative IOP/anterior chamber depth (preoperative IOP/ACD [PD ratio]) and preoperative IOP/retinal nerve fiber layer (RNFL) thickness (preoperative IOP/RNFL [PNFL ratio]) and preoperative IOP score x MD score x number of glaucoma medications (glaucoma index) predicted absolute IOP change in the POAG group, whereas preoperative IOP, PD ratio, PNFL ratio, and axial length (AL) did in the GS group. Preoperative IOP, PD ratio, and PNFL ratio predicted %IOP change in the POAG group, whereas only AL did in the GS group.In medically controlled POAG eyes, structural or functional parameters for glaucoma severity did not independently predict IOP change following phacoemulsification. However, novel severity indices obtained by addition of preoperative IOP and/or glaucoma medications to the structural or functional parameter predicted IOP changes.

Cataract, phacoemulsification and intraocular pressure: Is the anterior segment anatomy the missing piece of the puzzle?

Cataract extraction is a safe and effective surgery that has a lowering effect on the intraocular pressure. The specific mechanisms for this effect are still unclear. A direct inflammatory effect on the trabecular meshwork, alteration of the blood aqueous barrier, changes in the ciliary body and mechanical changes of the anterior segment anatomy are the key to understand cataract surgery and it's effects on aqueous humor dynamics. Additionally, with the advent of AS OCT, changes in the anterior segment of the eye have been studied and several parameters (such as lens vault, angle opening distance and anterior chamber depth) have been identified as predictors of intraocular pressure change. In eyes with narrow angles there is a greater drop in intraocular pressure after cataract surgery and it is correlated with parameters related to anterior chamber space. It is safe to affirm that cataract surgery is an important part of the modern glaucoma treatment and evidence should be analyzed as part of a bigger picture in order to more accurately understand its clinical relevance.

The Effects of Phacoemulsification on Intraocular Pressure and Topical Medication Use in Patients With Glaucoma: A Systematic Review and Meta-analysis of 3-Year Data

PURPOSE

For patients with comorbid cataract and primary open-angle glaucoma (POAG), guidance is lacking as to whether cataract extraction and traditional filtering surgery should be performed as a staged or combined procedure. Achieving this guidance requires an evidence-based understanding of the effects of phacoemulsification alone on intraocular pressure (IOP) in patients with POAG. For this reason, a systematic review and meta-analysis was undertaken to synthesize evidence quantifying the effect of phacoemulsification on IOP and the required number of topical glaucoma medications in patients with cataract and POAG.

MATERIALS AND METHODS

Database searches were last run on August 15, 2016 to identify potentially relevant studies. Identified articles were screened for relevance and meta-analysis was used to compute postoperative mean and percentage reduction in IOP (IOPR%) as well as mean difference in topical glaucoma medications.

RESULTS

The search strategy identified 1613 records. Thirty-two studies (1826 subjects) were included in quantitative synthesis. A 12%, 14%, 15%, and 9% reduction in IOP from baseline occurred 6, 12, 24, and 36 months after phacoemulsification. A mean reduction of 0.57, 0.47, 0.38, and 0.16 medications per patient of glaucoma medication occurred 6, 12, 24, and 36 months after phacoemulsification.

CONCLUSIONS

Phacoemulsification as a solo procedure does lower IOP in patients with POAG, and reduces dependency on topical glaucoma medications. These effects appear to last at least 36 months with gradual loss of the initial effect noted after 2 years. Certain populations appear to experience much greater reductions in IOP than others and future work to identify these high responding patients is needed.

Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis)

PURPOSE

To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery.

METHODS

This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders.

RESULTS

We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P<.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P<.001) in the wide-angle group (P=.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P<.001) reduction vs 2.5±3 mm Hg (16%, P<.001) in the wide-angle group (P=.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year (P<.05 for all).

CONCLUSIONS

In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option.

Lens Position Parameters as Predictors of Intraocular Pressure Reduction After Cataract Surgery in Glaucomatous Versus Nonglaucomatous Eyes

Purpose

To evaluate the relationship between lens position parameters and intraocular pressure (IOP) reduction after cataract surgery in patients with primary open-angle glaucoma (POAG) and in nonglaucomatous patients.

Methods

The main outcomes of this prospective study were percent and absolute IOP change, which were calculated using the preoperative IOP and the IOP 4 months after cataract surgery in POAG and nonglaucomatous eyes. Lens position (LP), defined as anterior chamber depth (ACD) + one-half lens thickness (LT), was assessed preoperatively using parameters from optical biometry. Preoperative IOP, axial length (AL), ACD, LT, relative lens position (RLP), and the ratio of preoperative IOP to ACD (PD ratio) were also evaluated as potential predictors of IOP change.

Results

Four months postoperatively, the average IOP reduction was 2.80 ± 3.83 mm Hg (15.79%) from the preoperative mean of 14.73 ± 2.89 mm Hg for nonglaucomatous eyes. The average IOP reduction was 2.66 ± 2.07 mm Hg (16.98%) from the preoperative mean of 14.86 ± 2.97 mm Hg for POAG eyes. Preoperative IOP, sex, AL, ACD, PD ratio, and LP predicted IOP change in nonglaucomatous eyes. Preoperative IOP and PD ratio predicted IOP change in POAG eyes.

Conclusions

Intraocular pressure reduction after phacoemulsification cataract surgery in nonglaucomatous eyes is significantly greater in more anteriorly positioned lenses. Though it did not reach statistical significance in patients with glaucoma, the association of LP with IOP reduction is in the same direction as in nonglaucomatous patients where smaller LP appears to predict greater IOP reduction. Lens position is a simple, easily calculable, accurate, and widely available parameter, which clinicians can potentially utilize in managing glaucoma.

Selective laser trabeculoplasty in pseudophakic and phakic eyes: a prospective study

AIM

To compare the efficacy of selective laser trabeculoplasty (SLT) in replacing medical therapy in pseudophakic and phakic eyes.

METHODS

Subgroup of a prospective randomized clinical trial including patients with primary open angle glaucoma or ocular hypertension controlled with medication. Of 38 pseudophakic eyes were matched with 38 phakic eyes. SLT was offered as a way to decrease medication while maintaining the same low eye pressure. SLT was performed over 360°, at 3ns, spotsize 400 µm, 100 spots. Data [intraocular pressure (IOP), number of medications needed] were measured at 1h, 1wk, 1, 3, 6 and 12mo. An independent-samples t-test was performed to compare baseline characteristics of the phakic and the pseudophakic group and differences in evolution of mean IOP and number of used medications. Chi-squared analysis was performed to investigate proportions of fast, slow and non-responders.

RESULTS

The mean IOP measurement was 13.00± 2.88 mm Hg in the phakic group (38 eyes) and 13.51±3.06 mm Hg in the pseudophakic group (38 eyes) (P>0.05). This changed little after SLT and IOP lowering effect was comparable between the two groups. Main aim however was to lower the amount of medication needed. In the phakic group medication lowered from 1.29±0.62 at baseline, to 0.15±0.46 after 12mo; a reduction of 88.37%. In the pseudophakic group, used medication changed from 1.71±1.04, to 0.41±0.61; a 76.02% reduction. The differences were not statistically significant at any time point (P>0.05). IOP lowering occurred slightly faster in the pseudophakic group (50% of patients after one week) than in the phakic group (68% of patients after more than 4wk). The difference was not significant (P>0.05).

CONCLUSION

IOP lowering effect of SLT is comparable between phakic and pseudophakic eyes.

Anterior Chamber Angle and Intraocular Pressure Changes After Phacoemulsification: A Comparison Between Eyes With Closed-angle and Open-angle Glaucoma

PURPOSE

To compare the angle and intraocular pressure (IOP) changes after phacoemulsification between eyes with closed-angle or open-angle glaucoma.

METHODS

Angle measurements using Visante AS-OCT imaging was performed for a prospective cohort of 24 subjects with closed-angle and 30 subjects with open-angle glaucoma before and 3 months after phacoemulsification. IOP measurement was measured at 6 and 12 months after surgery using Goldmann applanation tonometry as secondary outcome measures.

RESULTS

Eyes with closed angles were smaller than those with open angles (mean axial length 22.88 vs. 24.11 mm, P<0.001). Mean anterior chamber depth, area, volume, AOD500, AOD750, ARA, TISA500, and TISA750 increased after phacoemulsification in all eyes regardless of preexisting angle status (all P<0.001). Increase in AOD500, AOD750, TISA500, and TISA750 were greater in eyes with open angles compared with closed angles (P=0.03, 0.04. 0.04, 0.04, respectively). Mean IOP decreased by 1.8 and 2.1 mm Hg at 6 and 12 months, respectively, after phacoemulsification for all eyes (P<0.001 for both timepoints compared with preoperative baseline). However, postoperative reduction in the mean IOP was not significantly different between eyes with closed and open angles (Mann-Whitney test P=0.32 at 6 mo and P=0.75 at 12 mo postsurgery compared with preoperative).

CONCLUSIONS

Angle opening postphacoemulsification was considerable in all eyes. A similar IOP reduction after phacoemulsification was observed in all eyes regardless of angle status.

Evaluation of Anterior Segment Parameter Changes Using the Sirius after Uneventful Phacoemulsification

Purpose

To investigate changes in anterior chamber depth (ACD), corneal volume (CV), anterior chamber angle (ACA), anterior chamber volume (ACV), central corneal thickness (CCT), horizontal visible iris diameter (HVID), pupil diameter (PD), and intraocular pressure (IOP) after uneventful phacoemulsification cataract surgery with intraocular lens implantation.

Methods

A total of 132 eyes of 132 patients (87 men and 45 women) that underwent uneventful phacoemulsification cataract surgery and intraocular lens implantation were prospectively studied. The mean age of the patients was 63.68 ± 12.51 years. All patients were evaluated preoperatively and at 1 month postoperatively with the Sirius 3D Rotating Scheimpflug camera topography system. The ACD, CV, ACA, ACV, CCT, HVID, and PD measurements were recorded. IOP was measured using the Goldmann applanation tonometer, which was corrected for CCT of the Sirius device using Ehlers' formula.

Results

The preoperative mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 2.79 ± 0.45 mm, 124.73 ± 25.72 mm³, 42.09 ± 7.49⁰, 523.87 ± 41.97 microns, 55.37 ± 4.89 mm³, 3.98 ± 1.23 mm, 11.72 ± 0.67 mm, and 14.74 ± 2.59 mmHg, respectively. Three months postoperatively, the mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 3.45 ± 0.6 mm, 162.52 ± 23.79 mm³, 51.46 ± 5.63⁰, 526.21 ± 44.45 microns, 56.23 ± 5.12 mm³, 2.87 ± 0.45 mm, 11.91 ± 0.75 mm, and 12.02 ± 1.83 mmHg, respectively. There was a statistically significant increase in mean postoperative ACD, ACV, ACA, CV, and HVID compared with the corresponding preoperative values (p < 0.05). CCT remained stable after surgery. Postoperative PD and IOP were significantly decreased compared to corresponding preoperative values (p < 0.05).

Conclusions

Preoperative measurements by the Sirius 3D Rotating Scheimpflug camera topography system might help surgeons to predict postoperative changes resulting from phacoemulsification and intraocular lens implantation. This is a noncontact, noninvasive, and comfortable system for patients that is highly reliable and repeatable for anterior segment measurements.

Morphologic changes in the anterior segment using ultrasound biomicroscopy after cataract surgery and intraocular lens implantation

PURPOSE

To evaluate morphologic changes in the anterior segment using ultrasound biomicroscopic imaging (UBM) after phacoemulsification and foldable intraocular lens implantation (IOL).

METHODS

Thirty-six patients with a mean age of 68.68 ± 8.44 years (range 51-89) who had phacoemulsification and foldable IOL implantation were included in this prospective study. Several anterior segment parameters including aqueous depth (AQD), trabecular meshwork-iris angle (TIA), ciliary body thickness (CBT), sclera thickness (ST), trabecular meshwork-ciliary process distance (T-CPD), iris-ciliary processes distance (I-CPD), and iris thickness (IT) were measured using UBM preoperatively and at postoperative month 2.

RESULTS

There was a significant increase in AQD (p&lt;0.001) and TIA (p&lt;0.001) at postoperative month 2. However, CBT, ST, T-CPD, I-CPD, and IT did not significantly change (p&gt;0.05) during the study period.

CONCLUSIONS

Removal of the crystalline lens results in change in the anterior segment parameters. Our results confirmed that UBM is a helpful option for the analysis of anterior segment structures both qualitatively and quantitatively.

Lens Position Parameters as Predictors of Intraocular Pressure Reduction After Cataract Surgery in Nonglaucomatous Patients With Open Angles

Purpose

To evaluate the relationship between lens position parameters and intraocular pressure (IOP) reduction after cataract surgery in nonglaucomatous eyes with open angles.

Methods

The main outcome of the prospective study was percentage of IOP change, which was calculated using the preoperative IOP and the IOP 4 months after cataract surgery in nonglaucomatous eyes with open angles. Lens position (LP), defined as anterior chamber depth (ACD) + 1/2 lens thickness (LT), was assessed preoperatively using parameters from optical biometry. Preoperative IOP, central corneal thickness, ACD, LT, axial length (AXL), and the ratio of preoperative IOP to ACD (PD ratio) were also evaluated as potential predictors of percentage of IOP change. The predictive values of the parameters we found to be associated with the primary outcome were compared.

Results

Four months after cataract surgery, the average IOP reduction was 2.03 ± 2.42 mm Hg, a 12.74% reduction from the preoperative mean of 14.5 ± 3.05 mm Hg. Lens position was correlated with IOP reduction percentage after adjusting for confounders (P = 0.002). Higher preoperative IOP, shallower ACD, shorter AXL, and thicker LT were significantly associated with percentage of IOP decrease. Although not statistically significant, LP was a better predictor of percentage of IOP change compared to PD ratio, preoperative IOP, and ACD.

Conclusions

The percentage of IOP reduction after cataract surgery in nonglaucomatous eyes with open angles is greater in more anteriorly positioned lenses. Lens position, which is convenient to compute by basic ocular biometric data, is an accessible predictor with considerable predictive value for postoperative IOP change.

Lens parameters as predictors of intraocular pressure changes after phacoemulsification

PURPOSE

To evaluate intraocular pressure (IOP) change after cataract surgery in non-glaucomatous eyes with narrow and open angles (OAs) and its relation to novel lens parameters measured by anterior segment optical coherence tomography (AS-OCT).

SETTING

University affiliated hospital, Farabi Eye Hospital, Tehran, Iran.

DESIGN

Prospective interventional case series.

METHODS

In this prospective study, 85 non-glaucomatous eyes underwent phacoemulsification and lens implantation. Thirty-nine eyes had OAs and 46 eyes had narrow angles (NAs). IOP and biometric parameters were measured by AS-OCT preoperatively and 3 months after surgery. Change in IOP and its relation to biometric parameters, including lens vault (LV), anterior vault (AV), defined as the sum of the LV and the ACD, and relative LV (rLV), defined as the ratio of the LV to the AV, were evaluated. The main outcome measure was degree of IOP change after phacoemulsification.

RESULTS

Of the 85 patients included in the analysis, 35 were male and 50 were female with an overall mean age of 62.2 ± 8.9 years. The average IOP reduction was -4.95 ± 2.26 mm Hg, from a preoperative mean of 17.12 ± 2.47 mm Hg, at 3 months after cataract surgery. The amount of IOP reduction was significantly greater in the NA compared with the OA group. In multivariate linear regression analysis, preoperative IOP and AV were significantly associated with IOP decrease (all ≤ 0.03).

CONCLUSION

Cataract surgery results in IOP reduction in both OA and NA eyes. The amount of IOP reduction is related to AV.

Biometric and intraocular pressure change after cataract surgery

PURPOSE

To evaluate changes in ocular biometric parameters with optical biometry and intraocular pressure (IOP) by Goldmann tonometry after uneventful phacoemulsification in normotensive eyes.

METHODS

This prospective study was composed of 117 eyes of 117 patients who had undergone uncomplicated phacoemulsification and foldable intraocular lens implantation. The measurements were obtained preoperatively and 1 month postoperatively. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), pupil diameter (PD), and lens thickness were measured by the LenStar optical biometer, and IOP was measured by Goldmann applanation tonometry. The relationships between IOP change and ocular biometric parameters were evaluated.

RESULTS

Mean age was 64.73 ± 10.83 years; 45 patients were women (38.46%) and 72 patients were men (61.54%). Comparing preoperative and postoperative 1-month measurements, the mean AL, PD, and IOP decreased (p < 0.01), whereas ACD (p < 0.01) and CCT (p > 0.05) increased. Intraocular pressure change correlated positively with AL change (p < 0.05) and PD change (p < 0.05) and preoperative IOP (p < 0.01) and preoperative CCT (p < 0.05). Anterior chamber depth change correlated positively with preoperative ACD (p < 0.01) and negatively with preoperative PD (p < 0.05). Pupil diameter change positively correlated with preoperative PD (p < 0.01). Regression analyses showed that preoperative IOP significantly associated with postoperative IOP reduction according to the standardized coefficient beta (-0.649).

CONCLUSIONS

Anterior segment morphometry changed and IOP decreased after phacoemulsification. The preoperative IOP may be the best parameter for estimating postoperative IOP reduction.

[Influence of corneal pachymetric changes on functional results after cataract surgery]

BACKGROUND

In the early postoperative period following uncomplicated cataract surgery, the correlation of corrected distance visual acuity (CDVA) and the increase in corneal thickness and anterior chamber depth (ACD) are investigated.

PATIENTS AND METHODS

A total of 54 cataract patients with a mean age of 70 ± 8.4 years were included in this prospective study. Surgery was carried out on one eye of each patient according to the study protocol. Refraction, CDVA and ACD were evaluated 1 day and 1 week postoperatively and compared with the pachymetry results measured with the Pentacam.

RESULTS

The mean postoperative CDVA significantly improved from 0.31 ± 0.24 logMAR to 0.18 ± 0.22 logMAR after one day and up to 0.06 ± 0.13 logMAR one week after surgery (p < 0.05). The mean spherical equivalent was - 0.52 ± 0.69 D after one day and - 0.50 ± 0.82 D one week after surgery and showed only minimal differences compared to the mean target refraction of - 0.39 ± 0.70 D. Postoperative corneal thickness showed a significant increase compared to the preoperative results (p < 0.05) on both visits: the mean difference was 33.26 ± 50.20 µm (- 17 to 315 µm) on the first day and 20.22 ± 23.15 µm (- 10 to 99 µm) one week after surgery. Up to 7 days postoperatively the increase in corneal thickness and CDVA showed only moderate or no correlations (r = 0.465 vs. r = 0.072, respectively). Regarding pachymetry and ACD values, no or only low correlations were found.

CONCLUSION

The significant increase in corneal thickness on the first and seventh day shows no to moderate correlation to the CDVA. Nevertheless, a good and early rehabilitation of visual acuity following uncomplicated cataract surgery is possible. Intraocular pressure measurement can lead to false high results due to an increase in corneal thickness.

Efficacy of selective laser trabeculoplasty in phakic and pseudophakic eyes

PURPOSE

To compare the efficacy of selective laser trabeculoplasty (SLT) in phakic and pseudophakic eyes in open-angle glaucoma and ocular hypertension.

MATERIALS AND METHODS

Charts of 28 pseudophakic eyes and 60 phakic eyes that underwent 360-degree SLT were retrospectively reviewed. Patients were examined at 1, 3, 6, and 12 months. Treatment success was defined as ≥20% intraocular pressure (IOP) reduction, with no additional medications, laser, or glaucoma surgery. Mean IOP change, mean percentage of IOP reduction, and success rates for phakic and pseudophakic eyes were compared.

RESULTS

Mean percentage of IOP reduction post-SLT at 1-, 3-, 6-, and 12-month visits were 21.4%, 25.8%, 24.8%, and 23.7%, respectively, in the pseudophakic group and 22.8%, 25.0%, 25.7%, and 21.2%, respectively, in the phakic group. Success rates ranged between 60% and 64% in the pseudophakic group and between 58% and 73% in the phakic group. No statistically significant differences in IOP change, percentage of IOP reduction, and success rate were seen between the groups at any of the post-SLT visits (P>0.05).

CONCLUSIONS

Application of 360-degree SLT seems to be an efficient and safe treatment option for the management of phakic and pseudophakic open-angle glaucoma and ocular hypertension.

Cataract surgery and intraocular pressure

Cataract surgery is one of the most performed surgeries in the developed world. In addition to its significant impact on visual acuity, phacoemulsification has been hailed as a potential intraocular pressure (IOP)-lowering procedure. While current evidence suggests an overall significant and sustained decrease in IOP to exist after cataract surgery, the specific ocular characteristics that could help predict which patients are likely to benefit from this IOP-lowering effect remain unclear. This definition is important in glaucoma patients if this surgery is to be used in the treatment for this disease. Our review aims to summarize the literature on the subject, depicting possible mechanisms behind this IOP decrease, which type of patients are more likely to benefit from this surgery for IOP-lowering purposes and ultimately help optimizing disease management for the increasing number of patients with concomitant glaucoma and cataract.