Refractive outcomes of combined cataract and glaucoma surgery

No Changes in Keratometry Readings and Anterior Chamber Depth after XEN Gel Implantation in Patients with Glaucoma

Background: This study aimed to compare keratometry and anterior chamber depth (ACD) changes after XEN implantation in primary open-angle glaucoma (POAG) cases over a 3-month follow-up period. Methods: Twenty patients with POAG who underwent XEN63 implantation, either standalone or combined with cataract surgery, were included. Preoperative data, including best-corrected visual acuity (BCVA), refraction, gonioscopy, ophthalmoscopy, intraocular pressure (IOP) evaluation, and axial length, were collected. Corneal topography and ACD measurements were assessed preoperatively and at postoperative days 1, 7, 15, 30, 60, and 90. Each patient's eye that underwent XEN surgery was included in the study group, with the fellow eye serving as a control. Results: In the study group, there was a significant decrease in IOP after XEN stent implantation at all investigated time intervals (p < 0.05). However, changes in mean ACD did not show statistically significant differences at any follow-up examination in both the study and control groups. Additionally, keratometry readings revealed no significant changes in total astigmatism or steep keratometry values in either group. Conclusions: XEN implantation in POAG cases resulted in a significant decrease in IOP over the 3-month follow-up period. However, there were no significant changes observed in mean ACD or keratometry readings, indicating stability in these parameters post-XEN implantation. These findings suggest that XEN implantation may be an effective option for IOP reduction without affecting corneal curvature or ACD in POAG patients.

Comparative study of surgical outcomes of twin-site phacotrabeculectomy with mitomycin C in primary open-angle glaucoma versus primary angle-closure glaucoma

Purpose

To compare the surgical outcomes of twin-site phacotrabeculectomy with Mitomycin C (MMC) in primary open-angle glaucoma (POAG) versus primary angle-closure glaucoma (PACG).

Methods

Prospective, comparative, observational study. Patients with visually significant cataract and primary glaucoma were divided into two groups: POAG and PACG. They underwent twin-site phacotrabeculectomy with MMC and followed up on days 1, 15, 1 month, 6 months, and 12 months. Baseline and follow-up visits were compared to find the differences in intraocular pressure (IOP), antiglaucoma medications (AGM), success rates, anterior chamber depth (ACD), and axial length (AXL).

Results

There were 50 eyes each in POAG and PACG groups. Mean IOP reduction from baseline to 12 months (21.22 ± 6.0 to 11.40 ± 2.8-POAG group vs 24.16 ± 7.6 to 12.42 ± 3.2-PACG group) was statistically significant in both groups (P < 0.001), but no significant difference between groups (P = 0.095). There was a statistically significant decline in the number of AGM in POAG [1.66 (0.7) to 0.38 (0.7), P < 0.001] and PACG [2.10 (0.7) to 0.70 (0.8), P < 0.001]; the decline was more in POAG (P = 0.012) at last visit. Probability of overall (complete and qualified) success at 12 months postop was 72.0% [95% confidence interval (CI): 57.4-82.4] in PACG and 84.0% (95% CI: 70.5-91.7) in POAG group. There was a significant increase in ACD and a decrease in AXL in both groups (P < 0.001). More interventions were required in the PACG group (38, P = 0.012).

Conclusion

Phacotrabeculectomy with MMC causes a significant reduction in IOP and improvement in biometric parameters in both POAG and PACG. Patients with PACG required more postoperative interventions, while a lesser number of antiglaucoma medications were needed in POAG patients.

Factors Associated with Refractive Prediction Error after Phacotrabeculectomy

PURPOSE

To compare refractive prediction errors between phacotrabeculectomy and phacoemulsification.

METHODS

Refractive prediction error was defined as the difference in spherical equivalent between the predicted value using the Barrett Universal II formula and the actual value obtained at postoperative one month. Forty-eight eyes that had undergone phacotrabeculectomy (19 eyes, open-angle glaucoma; 29 eyes, angle-closure glaucoma) were matched with 48 eyes that had undergone phacoemulsification by age, average keratometry value and axial length (AL), and their prediction errors were compared. The factors associated with prediction errors were analyzed by multivariable regression analyses.

RESULTS

The phacotrabeculectomy group showed a larger absolute prediction error than the phacoemulsification group (0.51 ± 0.37 Diopters vs. 0.38 ± 0.22 Diopters, p = 0.033). Larger absolute prediction error was associated with longer AL (p = 0.010) and higher intraocular pressure (IOP) difference (p = 0.012). Hyperopic shift (prediction error > 0) was associated with shallower preoperative anterior chamber depth (ACD) (p = 0.024) and larger IOP difference (p = 0.031). In the phacotrabeculectomy group, the prediction error was inversely correlated with AL: long eyes showed myopic shift and short eyes hyperopic shift (p = 0.002).

CONCLUSIONS

Surgeons should be aware of the possibility of worse refractive outcomes when planning phacotrabeculectomy, especially in eyes with high preoperative IOP, shallow ACD, and/or extreme AL.

Premium Intraocular Lenses in Glaucoma-A Systematic Review

The incidence of both cataract and glaucoma is increasing globally. With increasing patient expectation and improved technology, premium intraocular lenses (IOLs), including presbyopia-correcting and toric IOLs, are being increasingly implanted today. However, concerns remain regarding the use of premium IOLs, particularly presbyopia-correcting IOLs, in eyes with glaucoma. This systematic review evaluates the use of premium IOLs in glaucoma. A comprehensive search of the MEDLINE database was performed from inception until 1 June 2023. Initial search yielded 1404 records, of which 12 were included in the final review of post-operative outcomes. Studies demonstrated high spectacle independence for distance and good patient satisfaction in glaucomatous eyes, with positive outcomes also in post-operative visual acuity, residual astigmatism, and contrast sensitivity. Considerations in patient selection include anatomical and functional factors, such as the type and severity of glaucomatous visual field defects, glaucoma subtype, presence of ocular surface disease, ocular changes after glaucoma surgery, and the reliability of disease monitoring, all of which may be affected by, or influence, the outcomes of premium IOL implantation in glaucoma patients. Regular reviews on this topic are needed in order to keep up with the rapid advancements in IOL technology and glaucoma surgical treatments.

Early post-operative anterior segment parameters modifications induced by PreserFlo MicroShunt in primary open-angle glaucoma

PURPOSE

The aim this study is to determine anterior chamber parameters variations induced by PreserFlo MicroShunt implantation, in the early post-operative days.

METHODS

This is a prospective observational study on 48 eyes undergoing PreserFlo MicroShunt implantation alone (n = 30) or combined with phacoemulsification (n = 18). Anterior chamber depth (ACD) and volume (ACV), central corneal thickness (CCT) and total corneal astigmatism (TCA) were evaluated pre-operatively, post-operatively at day-1 and at 1 week with the Pentacam tomography.

RESULTS

Intraocular pressure decreased significantly from 20.9 ± 4.0 to 8.0 ± 2.8 mmHg (p < 0.0001) and to 10.8 ± 3.7 mmHg (p = 0.0001) at day-1 and week-1, respectively. TCA varied significantly from baseline (1.5 ± 1.2 D) to both day 1 follow up (2.7 ± 1.9 D, p = 0.0003) and week 1 follow up (2.2 ± 1.6 D, p = 0.02). Nevertheless, only K1 showed a transient flattening at day 1, while K2 value didn't show any statistical variation in the early post-operative period. CCT value rose significantly at day 1 (547 ± 49 vs. 529 ± 32 µm at baseline, p = 0.04), but then returned toward pre-operative values at week 1 (537 ± 39 µm, p = 0.57). In contrast, ACD values changed insignificantly from 3.3 ± 0.9 to 3.7 ± 1.0 mm at day 1 (p = 0.21), and then stabilized at 3.4 ± 0.9 mm (p = 0.82) at week 1 follow up. ACV changed from 150.0 ± 36.2 to 159.5 ± 42.1 mm³ at day 1 (p = 0.58), and successively to 153.9 ± 37.9 mm³ at week 1 follow up (p = 0.96). The subgroup analysis in eyes undergoing standalone PreserFlo implantation didn't show significant changes in both ACD and ACV.

CONCLUSION

PreserFlo implantation minimizes the anterior chamber modifications generated by traditional filtering surgery, inducing low and transient corneal and biometric changes only in the very early postoperative period and insignificant changes to ACD and ACV, label of its safety and minimal invasiveness.

Refractive Outcomes for Combined Phacoemulsification and Glaucoma Drainage Procedure

INTRODUCTION

To evaluate the refractive outcome of combined cataract extraction and glaucoma drainage device (GDD) surgery.

METHODS

Patients who had undergone combined phacoemulsification with GDD surgery [Baerveldt, Abbott Medical, Abbott Park (IL) or Ahmed valve, New World Medical, Rancho Cucamonga (CA)] between June 2009 and August 2017 were included in the study. The main outcome measure evaluated was whether or not spherical equivalent (SE) between ± 1D from target refraction was achieved at 3-6 months postoperatively.

RESULTS

The final analysis included 42 eyes of 38 patients who underwent combined phacoemulsification and GDD surgery. A refractive outcome of spherical equivalent (SE) between ± 1D of the target refraction was achieved in 30 of 42 eyes (71.43%) at 3-6 months after surgery. Mean preoperative axial length (AL) of eyes with postoperative SE outside ± 1D from target (SD = 0.98, p = 0.003) was noted to be 25.37 ± 0.98 mm (longer mean AL) and that of eyes with SE between ± 1D (SD = 0.89, p = 0.000) was found to be 23.34 ± 0.89 mm (average mean AL). Twelve (29%) eyes were noted to have a mean 0.52D (SD = 0.49; range 0.02-1.49) of corneal astigmatism induced by combined surgery. Age, central corneal thickness, preoperative anterior chamber depth, and pre- and postoperative intraocular pressure did not significantly affect refractive outcomes.

CONCLUSION

Refractive outcomes within 1.00D of the target refraction were achieved in most patients undergoing a combined surgical approach. Longer AL was a risk factor among patients with refractive change > 1.00D from target.

Comparison of refractive outcomes after combined cataract and glaucoma surgery: trabeculectomy and glaucoma drainage device implantation

PURPOSE

To investigate the refractive outcome of combined cataract surgery and glaucoma drainage device (GDD) implantation compared with trabeculectomy and cataract surgery.

SETTING

Department of Ophthalmology, National University Health System, Singapore.

DESIGN

Retrospective cohort study.

METHODS

206 eyes were enrolled for analysis: 50 had combined cataract surgery and trabeculectomy (trabeculectomy group), 50 had combined cataract surgery and GDD implantation (GDD group), and 106 had cataract surgery alone (control group). Refractive prediction error and absolute prediction error of each glaucoma surgery group were compared with the control group. Subgroup analysis was performed in the following axial length (AL) subgroups: short (<22.5 mm), medium (≥22.5 to <25.5 mm), and long (≥25.5 mm).

RESULTS

In total, 206 eyes were examined. There was no statistically significant difference in the overall refractive prediction error between the GDD (0.00 ± 0.54 diopters [D]) and the control group (0.10 ± 0.53 D, P = .58). There was significant myopic refractive prediction error in the trabeculectomy group (-0.18 ± 0.88 D, P = .020). In eyes with short AL, a greater absolute prediction error was observed in the GDD group (-0.75 ± 0.43 D, P = .039).

CONCLUSIONS

Apart from a significant deviation in short AL eyes, combined cataract surgery and GDD implantation demonstrated no significant postoperative refractive prediction error.

Changes to Corneal Topography and Biometrics after PRESERFLO Microshunt Surgery for Glaucoma

PRECISE

Glaucoma surgery with the PRESERFLO Microshunt shows mild and transient changes in the corneal astigmatism, the corneal elevation and biometrics in the early postoperative period. The posterior corneal elevation tends to be higher in POAG.

PURPOSE

To determine the changes in the corneal keratometry, astigmatism and elevation, refraction, axial length and anterior chamber depth and volume after the implantation of the PRESERFLO Microshunt in patients with primary open angle glaucoma (POAG) in the early postoperative period.

METHODS

Patients diagnosed with primary open angle glaucoma (POAG) who underwent an ab-externo SIBS (poly(styrene-block-isobutylene-block-styrene) microshunt implantation were recruited. The central corneal thickness (CCT), the intraocular pressure (IOP), best corrected visual acuity (BCVA), refraction, biometrics and corneal topography with a Scheimpflug topographer were analyzed preoperatively and 24 hours, 1 week, 1 month and 3 months after surgery.

RESULTS

A total of 30 eyes of 29 patients were included. In 24 eyes the device was implanted as a standalone procedure and in 6 eyes it was combined with cataract surgery. The results were analyzed separately. The IOP decreased from 21.8±5.2 and 16.5±1.5▒mmHg at baseline to 10.9±1.8 and 10.1±1.1mmHg at 3 months in the non-combined and combined groups (P<0.01). The anterior, posterior and total corneal astigmatism (ASA, PSA, TCA) increased in each group 0.4±0.3/ 0.2±1.0 D, 0.08±0.1/ 0.03±0.1 D and 0.4±0.3/ 0.2±0.9 D respectively at 3 months. The anterior and posterior corneal elevation (ACE max, ACE min, PCE max) increased on the first week (P=0.01) with no significant changes at 3 months in the non-combined group. The changes observed in the combined group were not significant. The axial length (AL) decreased 0.13±0.23 and 0.2±0.07▒mm in each group (P=0.01). There was a significant correlation between the IOP and the maximum elevation of the posterior surface of the cornea at the preoperative examination (r=0.93, P= 0.02).

CONCLUSIONS

The PRESERFLO Microshunt implant for glaucoma surgery induces mild and transient changes in corneal astigmatism, axial length and anterior chamber depth in the early post-operative period.

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

Purpose

To compare the predictability of biometric results in patients undergoing cataract surgery combined with Ahmed glaucoma valve (AGV) implantation according to tube position.

Methods

A retrospective cohort study was performed in patients who underwent phacoemulsification surgery combined with AGV implantation with the tube in posterior (group PC) and anterior (group AC) chamber, between November 2012 and April 2020. The main outcome was the mean biometric prediction error, according to tube position, using different formulas.

Results

The study included 49 eyes of 36 patients, 23 eyes in group PC and 26 eyes in group AC. Gender (p=0.774), age (p=0.822), type of glaucoma (p=0.168), preoperative correct distance visual acuity (p=0.139), axial length (p=0.765), anterior chamber depth (p=0.351), keratometry (p=0.577) and intraocular lens power (p=0.608) were similar between groups. Only preoperative intraocular pressure was higher in group PC (p=0.005). The mean prediction errors using Haigis, SRK/T, Hoffer Q, Holladay 1, Barrett Universal II, Kane and Hill RBF formulas were all positive in group PC (hyperopic) and all negative (myopic) in group AC. In group PC, there was no significant difference in prediction error between these formulas (p>0.05). In group AC, the formula with the worst prediction error was Haigis (p=0.001), and the best was Barrett Universal II (p=0.043).

Conclusion

The biometric predictability and expected final refraction in phacoemulsification surgery combined with AGV implantation are modified by the position of the tube.

Long-term outcomes of prediction error after combined phacoemulsification and trabeculectomy in glaucoma patients

Background

To investigate long-term outcomes of prediction error after phacotrabeculectomy and to determine risk factors that may cause unstable prediction error after phacotrabeculectomy in glaucoma patients.

Methods

A total 120 eyes of 120 patients who had underwent uncomplicated phacotrabeculectomy (combined group) or phacoemulsification (phaco-only group) were included. Best-corrected visual acuity (BCVA), intraocular pressure (IOP) were measured before and after surgery, and anterior segment parameters including anterior chamber depth (ACD), lens vault (LV), and anterior vault (AV) measured using anterior-segment optical coherence tomography were compared between the two groups. The mean absolute error (MAE) at 3, 6, 12, and 24 months postoperatively were compared. Risk factors associated with unstable prediction error (MAE ≥ 0.5) were investigated in the combined group.

Results

In both groups, BCVA was improved and IOP was decreased significantly. MAE at 3, 6, 12, 24 months postoperatively were not significantly different between two groups. The risk factors for unstable prediction error after 12 months of phacotrabeculectomy were old age and LV. Whereas, the only factor predicting unstable prediction error after 24 months of phacotrabeculectomy was LV. The cut-off value of LV for predicting unstable refractive error analyzed by the ROC curve was 0.855 mm.

Conclusions

Phacotrabeculectomy may be an effective treatment with stable long-term outcomes of prediction error similar to phacoemulsification in patients with glaucoma. However, elderly patients or patients with large LV may be predisposed to unstable prediction error after phacotrabeculectomy.

Phacotrabeculectomy versus Phaco with Implantation of the Ex-PRESS Device: Surgical and Refractive Outcomes-A Randomized Controlled Trial

The aim of this study was to compare surgical and refractive outcomes between phacotrabeculectomy (P-Trab) and phaco with Ex-PRESS (P-Ex-PRESS) for glaucoma at a 6-month follow-up. This prospective randomized controlled trial included 81 eyes; 43 eyes (53%) and 38 eyes (47%) were assigned to the P-Ex-PRESS and P-Trab groups, respectively. Refraction, intraocular pressure (IOP), and best-corrected visual acuity were measured. Refractive change was analyzed using the cylinder’s magnitude, and polar analysis assessed the change in the trend of astigmatism [with-the-rule, against-the-rule (ATR), oblique (OBL)], evaluating mean astigmatism in centroid form. All patients showed a statistically significant postoperative decrease in IOP (P < 0.05). There were no differences between the groups in terms of postoperative IOP and visual outcomes or in astigmatism preoperatively or postoperatively (P = 0.61, P = 0.74). In both groups, the mean preoperative and postoperative astigmatism were ATR and OBL, respectively. Preoperative and postoperative centroids in the P-Ex-PRESS group were 0.44 ± 1.32 D at 177° and 0.35 ± 1 D at 8°, respectively, (P = 0.5) and in the P-Trab group were 0.16 ± 1.5 D at 141° and 0.39 ± 1.38 D at 29°, respectively (P = 0.38). Both P-Ex-PRESS and P-Trab showed comparable antihypertensive efficacy in treating open-angle glaucoma over 6 months. Preoperative and postoperative astigmatism did not differ between groups. The groups showed comparable results for final visual acuity.

[Clinical significance of aberrations of the ocular optical system in glaucoma surgery and the capabilities of minimizing them]

INTRODUCTION

Despite the achievements of modern pharmacology and laser surgery, traditional glaucoma surgery remains the main method of reducing intraocular pressure (IOP). After successful glaucoma surgery, some of the patients are observed to have a decrease in visual functions not associated with progression of the glaucomatous process. This phenomenon is explained by the effect glaucoma surgery can have on eye refraction; detailed understanding of such changes would significantly speed up functional rehabilitation of these patients.

PURPOSE

To study the time course of clinical manifestations of aberrations of the ocular optical system in the surgical treatment of glaucoma and to assess the effectiveness of the method used to minimize them.

MATERIAL AND METHODS

The study included 32 patients (32 eyes), aged from 52 to 73 years. The patients were divided into 2 groups. Patients of the first group (20 eyes) were treated with standard non-penetrating deep sclerectomy (NPDS). In the second group (12 eyes), patients underwent a modified NPDS according to an original method proposed by us. All patients were examined before and monitored after the surgery including precision visometry and corneal topography.

RESULTS

A significant change in the studied parameters was observed in the first group in the early postoperative period (3rd day) - the average value of corneal astigmatism increased from 0.83±0.12 D to 2.86±0.07 D, while in the second group it increased from 0.86±0.20 D to 1.36±0.12 D.

CONCLUSION

Non-penetrating deep sclerectomy according to the modified method proposed by us helps achieve higher functional results in the early postoperative period due to the reduction of induced changes in eye refraction.

Refractive Outcomes After Trabecular Micro-Bypass Stents (iStent Inject) with Cataract Extraction in Open-Angle Glaucoma

Purpose

Simultaneous cataract and glaucoma surgery has traditionally been challenging for the anterior segment surgeon. The introduction of minimally invasive glaucoma surgery (MIGS) in conjunction with cataract surgery appears safe and effective in lowering intraocular pressure. Although a significant visual impact leading from the combined procedure is unexpected, we aim to describe the refractive outcomes in a cohort of patients undergoing simultaneous cataract removal and iStent inject and discuss the potential implications of combined surgery in patients with co-existent glaucoma.

Patients and Methods

This is a retrospective consecutive case series inclusive of patients undergoing combined femtosecond laser-assisted cataract surgery and the insertion of two trabecular micro-bypass stents (iStent inject). Visual acuity, refraction and astigmatic vector analysis were collated and analysed from the preoperative and 4 weeks postoperative visits.

Results

One hundred and six eyes of 89 patients from 2 surgeons were included in the original cohort. The mean absolute difference from target refraction was 0.36 ± 0.25D. 73.9% of eyes were within ± 0.5D of the refractive target and 98.9% of eyes were within ± 1.00D. 73.8% of eyes had 0.5D or less residual refractive astigmatism following the procedure.

Conclusion

We present a novel cohort of glaucoma patients undergoing combined trabecular micro-bypass stents (iStent inject) and cataract surgery achieving excellent refractive outcomes. The results of this study indicate that this second-generation device is refractively neutral.

Long-term comparison of postoperative refractive outcomes between phacotrabeculectomy and phacoemulsification

PURPOSE

To compare long-term postoperative refractive outcomes between phacotrabeculectomy and phacoemulsification, both with posterior chamber intraocular lens implantation.

SETTING

Department of Ophthalmology, Konyang University, Kim's Eye Hospital, Myung-Gok Eye Research Institute, Seoul, South Korea.

DESIGN

Retrospective comparative study.

METHODS

Postoperative refractive outcomes were compared between patients with cataract and coexisting primary or secondary open-angle glaucoma (OAG) who had phacotrabeculectomy (combined group) and patients with cataract with or without coexisting OAG who had phacoemulsification alone (phaco-only group). The refractive prediction error, mean absolute error, and median absolute error were compared between groups. Subgroup analysis based on preoperative axial length (AL) was performed (medium >22.0 to <24.5 mm; medium-long ≥24.5 to <26.0 mm; long ≥26.0 mm).

RESULTS

The combined group comprised 51 eyes and the phaco-only group, 74 eyes. The mean interval between surgery and refraction measurement was 14.70 months ± 10.80 (SD) (median 13.0 months) and 4.81 ± 4.97 months (median 2.0 months), respectively. Postoperatively, there was no statistically significant between-group difference in the following mean values: refractive prediction error, -0.05 ± 0.64 versus -0.04 ± 0.52 (P = .905); mean absolute error, 0.46 ± 0.44 versus 0.38 ± 0.36 (P = .258); median absolute error, 0.32 (interquartile range [IQR], 0.17, 0.67) versus 0.28 (IQR, 0.13, 0.54) (P = .297). Subgroup analysis also did not show significant differences between the 2 groups (all P > .05).

CONCLUSION

The long-term postoperative refractive outcomes of phacotrabeculectomy and phacoemulsification alone were not significantly different in eyes with OAG, regardless of preoperative AL.

Ocular biometric changes after Ahmed glaucoma valve implantation

PURPOSE

To investigate the ocular biometric changes after uneventful Ahmed glaucoma valve implantation.

METHODS

Patients with refractory glaucoma who were candidate for Ahmed valve surgery were prospectively included in this study. Patients with a history of any kinds of corneal surgery were excluded. Refractive status, intraocular pressure, axial length, anterior chamber parameters including anterior and posterior mean keratometry, central corneal thicknesses, and anterior chamber depth, anterior chamber volume, and anterior chamber angle were evaluated at baseline and 1 and 3 months after surgery.

RESULTS

A total of 20 eyes from 20 patients were included. Mean intraocular pressure at baseline was 33.4 ± 12.3 mm Hg that significantly decreased to 14.6 ± 6.2 mm Hg at 1 month and 13.5 ± 4.3 mm Hg at 3 months after Ahmed glaucoma valve implantation (p < 0.001). Mean number of medications was 3.6 ± 1.3 at baseline which significantly decreased to 1.0 ± 1.3 at 3 months after Ahmed glaucoma valve implantation (p < 0.001). Axial length decreased significantly from 23.69 ± 1.95 to 23.47 ± 1.91 mm (p < 0.001) at month 3. There were no significant changes in other parameters such as mean spherical equivalent, anterior chamber volume, anterior chamber angle, anterior chamber depth, and keratometry at the end of month 3 after surgery (p > 0.05 in all).

CONCLUSION

Ahmed glaucoma valve implantation had a significant effect on axial length at 3 months after surgery but its effect on keratometry and other anterior chamber parameters was not significant.

[Refractive shift after glaucoma surgery]

Filtering glaucoma surgery can affect certain biometric features of the eye: it can change the axial length and anterior chamber depth, while redistribution of mechanical tensions in the fibrous tunic can alter the shape of the cornea. Among these changes that affect refraction, reshaping of corneal curvature is the principle one. Contrary to the expectations, and in contrast to changes associated with cataract surgery, glaucoma surgery led to decrease in vertical corneal radius (steepening) and development of the with-the-rule astigmatism. A number of studies helped reveal the features of corneal astigmatism that appears after glaucoma surgery: its power, duration, possibility of horizontal meridian flattening, influence of topical cytostatic drugs and drainage devices, etc. Potential reasons of astigmatism development were suggested: conjunctival incisions and sutures in the limbal area, quantity and strength of flap sutures, intraocular pressure level, shift of fistula edges, tissue contraction after cauterization, etc. The key role in pathogenesis of the refractive shift due to change of corneal curvature may belong to particularities of wound healing in the cornea and sclera: healing in sclera is similar to one of connective tissue - its ultrastructure undergoes aging process followed by change of rigidity. At the same time, the main reason for the development of corneal astigmatism after glaucoma surgery remains unclear.

Rotational stability of a new multicomponent intraocular lens

Purpose

To evaluate the rotational stability of the Precisight multicomponent intraocular lens (MCIOL) following primary implantation and after enhancement procedures.

Patients and methods

Prospective, single-center study of eyes that underwent routine cataract surgery with implantation of a non-toric MCIOL, (Precisight, InfiniteVision, Optics, Strasbourg, France). The axis of the MCIOL was measured with a line bisecting the two dialing holes in the front lens. Intraoperative orientation was determined using a digital surgical guidance system while the postoperative orientation was determined using slit-lamp imaging. Two populations were analyzed: eyes that only underwent cataract surgery (PRIM) and eyes that also underwent enhancement (ENH), consisting of surgical front optic exchange. Both populations had 3 observation visits: first implantation (P-Op); 3 months (3mo) and 6 months (6mo) after primary surgery. The ENH group had an additional fourth visit that corresponded to the enhancement surgery (E-Op). The main outcome measure was mean absolute change in MCIOL orientation (degrees). The effects of axial length (AL) and anterior chamber depth (ACD) on IOL rotational stability were examined.

Results

Thirty-three eyes received MCIOL of which 29 had usable orientation images. Of these, 12 were in the PRIM group and 17 underwent ENH. Regarding the mean absolute rotation, among PRIM eyes, P-Op to 3mo was 3.03±2.45 degrees; P-Op to 6mo, 2.28±1.54 degrees; and 3–6mo, 2.37±1.56 degrees. Among the ENH eyes, P-Op to 3mo was 3.09±1.68; E-Op to 6mo, 2.71±3.30 and P-Op to 6mo, 3.62±3.42. There were no significant differences in the IOL rotation. There were no statistical differences in rotational stability between the ENH and PRIM groups. There was no correlation between IOL rotation and AL or ACD.

Conclusion

Precisight appears to be rotationally stable. The enhancement procedure does not affect rotational stability.

Refractive outcomes among glaucoma patients undergoing phacoemulsification cataract extraction with and without Kahook Dual Blade goniotomy

BACKGROUND

Glaucoma patients undergoing phacoemulsification alone have a higher rate of refractive surprise compared to patients without glaucoma. This risk is further increased with combined filtering procedures. Indeed, there are few and conflicting reports on the effect of combined phacoemulsification and micro-invasive glaucoma surgery (MIGS). Here, we look at refractive outcomes of glaucoma patients undergoing phacoemulsification with and without Kahook Dual Blade (KDB) goniotomy.

METHODS

Retrospective chart review of 385 glaucomatous eyes of 281 patients, which underwent either phacoemulsification alone (n = 309) or phacoemulsification with KDB goniotomy (n = 76, phaco-KDB) at the University of Colorado. The main outcome was refractive surprise defined as the difference in target and postoperative refraction spherical equivalent greater than ±0.5 Diopter (D).

RESULTS

Refractive surprise greater than ±0.5 D occurred in 26.3% of eyes in the phaco-KDB group and 36.2% in the phacoemulsification group (p = 0.11). Refractive surprise greater than ±1.0 D occurred in 6.6% for the phaco-KDB group and 9.7% for the phacoemulsification group (p = 0.08). There was no significant difference in risk of refractive surprise when pre-operative IOP, axial length, keratometry or performance of KDB goniotomy were assessed in univariate analyses.

CONCLUSION

There was no difference between refractive outcomes of glaucomatous patients undergoing phacoemulsification with or without KDB goniotomy.

Refractive outcomes after trabecular microbypass stent with cataract extraction in open-angle glaucoma

PURPOSE

To evaluate the impact of trabecular microbypass stents combined with cataract surgery on refractive outcomes in patients with open-angle glaucoma (OAG).

SETTING

Private practice, Sioux Falls, South Dakota, USA.

DESIGN

Retrospective, comparative case series.

METHODS

Eyes with OAG had implantation of trabecular microbypass stents with concomitant cataract surgery. The unmatched control group comprised eyes that underwent only cataract extraction. Data were collected preoperatively and postoperatively for 6 months. Data included spherical equivalent (SE), astigmatic error, intraocular pressure (IOP), and number of glaucoma medications.

RESULTS

The series included 76 consecutive OAG eyes with combined cataract plus trabecular microbypass stent and 50 consecutive non-OAG eyes with cataract surgery only. SE outcomes were equivalent between the groups (P<0.001). For the combined and cataract-only groups respectively, 46% vs 52% had SEs within 0.25 D of the target, 80% vs 80% within 0.50 D, and 95% vs 94% within 1.00 D. Astigmatism outcomes did not significantly differ between the groups (P>0.05). As for magnitude of astigmatism in the combined and cataract only groups respectively, 51% vs 32% were within 0.5 D, 75% vs 66% within 1.0 D, 87% vs 82% within 1.5 D, and 89% vs 94% within 2.0 D. In the OAG combined-surgery group, mean intraocular pressure reduction was 3.4 mmHg (P<0.0001) at 1 month postoperatively, 4.0 mmHg (P<0.0001) at 3 months, and 3.4 mmHg (P<0.01) at 6 months. Mean decrease in number of glaucoma medications was 0.4 (P<0.05) at 1 month, 0.7 (p<0.0001) at 3 months, and 0.9 (P<0.001) at 6 months.

CONCLUSION

The results of this study suggest the trabecular microbypass stent is a refractively neutral device.

Comparative analysis of optical aberrations, anatomical and optical parameters of the cornea in glaucoma surgery

Purpose. A combined comparative study of the impact of antiglaucomatous surgeries on the anatomical and optical parameters of the cornea.

Materials and methods. The study involved 38 patients (38 eyes) aged 43 to 75 with primary open-angle glaucoma (POAG), which were divided into 2 groups. Patients of group I (15 eyes) underwent classical deep sclerectomy (DSE), while those of group II (23 eyes), had non-penetrating deep sclerectomy (NDSE). All patients underwent a comprehensive examination before and after surgery, including precision visometry, corneal topography, OCT pachymetry.Results. Group I revealed a significant change in the parameters on the 3rd day after the surgery; in particular, the average value of corneal astigmatism increased from -0.93 D to -3.62 D, the curvature radius of the cornea in the vertical meridian increased from 7.56 ± 0.07 mm to 8.34 ± 0.04 mm, the thickness of the central cornea changed from 514.5 ± 0.04 μm to 520.6 ± 0.06 μm. In group II, the corneal astigmatism increased from -0.86 D to -2.75 D, and the curvature radius of the cornea in the vertical meridian changed from 7.72 ± 0.05 mm to 8.12 ± 0.03 mm, the central thickness of the cornea increased from 515.4 ± 0.04 to 516.8 ± 0.12 μm.

Conclusion. The degree of surgically induced changes of anatomic and optical parameters of the cornea in POAG patients depended on the amount of intervention: NDSE has a lesser effect on these parameters than classical DSE.

Factors Associated with Outcomes of Combined Phacoemulsification and Ahmed Glaucoma Valve Implantation

Purpose

To evaluate outcomes and factors associated with surgical failure in patients who underwent combined phacoemulsification and Ahmed glaucoma valve (AGV) implantation.

Methods

This retrospective and longitudinal study enrolled 40 eyes (38 patients) that underwent combined phacoemulsification and AGV implantation. Visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as a last follow-up IOP of 6 to 21 mmHg without medication, qualified success as an IOP of 6 to 21 mmHg with medication, and failure as an IOP of >21 or <6 mmHg.

Results

The mean follow-up period was 18 ± 10 months. Preoperative diagnoses were chronic angle closure glaucoma (35.0%), neovascular glaucoma (22.5%), uveitic glaucoma (17.5%), primary open-angle glaucoma (15.0%), and other (10.0%). IOP decreased from a mean of 30.5 ± 8.7 to 14.5 ± 3.7 mmHg at the last follow-up visit (p < 0.001). Treatment was classified as qualified success in 18 eyes (45%), complete success in 15 (37.5%), and failure in seven (17.5%). Twenty-two eyes (55%) showed improvement in visual acuity. The most common postoperative complication was a transient hypertensive phase (five eyes, 12.5%). Tube-iris touch was associated with surgical failure (hazard ratio, 8.615; p = 0.008).

Conclusions

Combined phacoemulsification and AGV implantation is an effective and safe surgical option for patients with refractory glaucoma and cataract. Postoperative tube-iris touch is an indicator of poor prognosis.

Comparison of the Ahmed and Baerveldt glaucoma shunts with combined cataract extraction

OBJECTIVE

To compare the surgical outcomes of combined phacoemulsification with either Ahmed glaucoma valve (AGV) or Baerveldt glaucoma implant (BGI).

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 104 eyes that underwent combined phacoemulsification with either AGV (PhacoAGV; n = 57) or BGI (PhacoBGI; n = 47) implantation.

METHODS

Failure was defined as uncontrolled intraocular pressure (IOP; <5 mm Hg, ≥18 mm Hg, or <20% reduction), additional glaucoma surgery, vision-threatening complications, or progression to no-light-perception vision.

RESULTS

The PhacoAGV group was older (p = 0.03), had poorer baseline visual acuity (VA; p = 0.001), and had fewer previous glaucoma surgeries (p = 0.04). Both groups had similar baseline IOP (PhacoAGV: 26.4 ± 8.3 mm Hg; PhacoBGI: 25.7 ± 7.3; p = 0.66) and glaucoma medications (PhacoAGV: 3.8 ± 1.0; PhacoBGI: 3.6 ± 1.5; p = 0.54). At 2 years, failure rates were 44% in the PhacoAGV group and 23% in the PhacoBGI group (p = 0.02). Both groups had similar mean IOP reduction (PhacoAGV: 45%; PhacoBGI: 47%, p = 0.67) and medication use reduction (PhacoAGV: 47%; PhacoBGI: 58%, p = 0.38). The PhacoBGI group had higher IOP and medication use up to 1 month (p < 0.05). Both groups improved in VA from baseline (p < 0.05) and had similar overall complication rates (p = 0.31). The PhacoBGI group required more overall interventions (p < 0.0005).

CONCLUSIONS

This comparative study found no difference in IOP, glaucoma medications, or complication rates between PhacoAGV and PhacoBGI at 2 years, despite BGIs being implanted in patients at higher risk for failure. The PhacoAGV group had higher failure rates at 2 years. Both groups had significant improvements in VA due to removal of their cataracts. The PhacoBGI group required more interventions, but most of these were minor slit-lamp procedures.

Glaucoma surgery and induced astigmatism: a systematic review

Background

The refractive outcomes of glaucoma surgeries, particularly their effect on astigmatism, are incompletely understood.

Main body

Trabeculectomy is associated with a considerable amount of with-the-rule astigmatic change in the immediate postoperative period. This is followed by a gradual against-the-rule shift. These changes are altered with the use of mitomycin C (MMC). Non-penetrating surgery such as deep sclerectomy is also associated with a similar or smaller degree of induced astigmatism. Minimally invasive glaucoma surgery appears to be astigmatically neutral. There is no clear evidence regarding refractive outcomes of glaucoma drainage device surgery.

Conclusions

Induced astigmatism may account for a reduction in unaided visual acuity in the early postoperative period following a successful trabeculectomy. These changes appear to stabilise at 3 months, and it would be prudent to defer the prescription of new glasses until this time. If sequential cataract surgery is to be performed, toric intraocular lenses can be a useful option for astigmatic correction.

Combined Approach to Phacoemulsification and Trabeculectomy Results in Less Ideal Refractive Outcomes Compared With the Sequential Approach

PURPOSE

To compare the refractive outcomes of combined versus sequential trabeculectomy and then phacoemulsification.

METHODS

We compared eyes that underwent uncomplicated combined phacotrabeculectomy (combined group, 87 eyes), phacoemulsification at least 3 months after trabeculectomy (sequential group, 56 eyes), and phacoemulsification only (control group, 78 eyes) between January 1, 2006 and January 1, 2014. The main outcome measure was refractive prediction error (RPE)-defined as postoperative subjective spherical equivalent refraction minus predicted spherical equivalent refraction.

RESULTS

The study population was predominantly Chinese and the mean age at their cataract surgery was 67.2±9.59 years. Compared with controls, RPE (-0.40±0.70 vs. -0.01±0.50, P<0.001) and mean absolute error (0.62±0.50 vs. 0.39±0.31, P=0.003) were greater for the combined group but not for the sequential group. Proportionately fewer patients in the combined group achieved final subjective refraction within ±0.5D (27.6% vs. 46.2%, P=0.01) compared with controls. Within the sequential group, there were no differences in RPE when the fellow eye axial length was used to predict refractive outcome (P=0.17) or between the group with precataract surgery IOPs of ≤11 mm Hg (-0.28±0.82) and the group with >11 mm Hg (-0.28±0.53, P=0.99). For the sequential group, the use of contact A scan yielded less RPE compared with IOLMaster (P=0.01).

CONCLUSIONS

Combined approach to trabeculectomy and phacoemulsification resulted in greater myopic RPEs that were expectedly greater than those found in the phacoemulsification group.

Predictive factors of visual outcome of Malaysian cataract patients: a retrospective study

AIM

To explore the associations between various characteristics of Malaysian cataract patients and their management, and their post-operative visual outcomes, to inform relevant bodies to reduce cataract-related blindness.

METHODS

We conducted a descriptive secondary data analysis of cataract surgery patients in Melaka Hospital, from 2007 to 2014 using the National Eye Database (NED). Patient-related factors (demographic features, systemic and ocular comorbidities) and management-related factors (surgical duration, type of surgery, type of lens) were analysed for their association with visual outcome (acuity).

RESULTS

Most patients were Malays (48.23%) and Chinese (38.55%) aged 60-79y (range 0-100y). Hypertension (58.61%) and diabetes (44.89%) were major systemic comorbidities. Glaucoma (6.71%) and diabetic retinopathy (10.12%) were the main ocular comorbidities. Other comorbidities were age-related macular degeneration, pterygium, corneal opacities, macula diseases, vitreous haemorrhage, retinal detachment and pseudoexfoliation (0.70%-1.60%). Preoperatively 7150 (55.03%) eyes presented with poor vision. Uncomplicated phacoemulsification performed quickly with foldable lenses gave good results.

CONCLUSION

Primary care physicians should initiate early detection to prevent late presentation of cataracts causing poor vision and should discuss the risks and benefits of cataract surgery while emphasizing the role of pre-existing comorbidities which may affect the visual outcomes. For good results, phacoemulsification should be done within 30min, without complications, using foldable posterior chamber intraocular lens.

Intraocular Pressure, Axial Length, and Refractive Changes after Phacoemulsification and Trabeculectomy for Open-Angle Glaucoma

PURPOSE

To compare changes in intraocular pressure (IOP), axial eye length (AEL), and refractive outcome in primary open-angle glaucoma patients undergoing cataract surgery and trabeculectomy in dependence of the sequence of surgeries.

MATERIALS AND METHODS

We retrospectively analysed 48 eyes. The changes in refraction, intraocular pressure, and axial eye length were analysed after surgery. In group A (21 subjects), phacoemulsification was performed before trabeculectomy, and in group B (27 subjects), trabeculectomy was performed before phacoemulsification with a minimum time span between interventions of 6 months.

RESULTS

The reduction in IOP and the decrease in AEL after trabeculectomy were significant after 6 and 12 months postsurgery (p < 0.001 each). The decrease in AEL was 0.42 ± 0.11% at 6 months after surgery and 0.40 ± 0.13% after 12 months from surgery; this decrease in AEL was comparable between the groups. The refractive outcome was significantly different between the groups (group A: 0.35 ± 0.75 dpt, group B: -0.05 ± 0.36 dpt, p = 0.018); in group A, trabeculectomy caused a hyperopic shift of 0.34 ± 0.44 dpt (p = 0.002) at 12 months postsurgery.

CONCLUSION

IOP reduction after trabeculectomy causes AEL shortening. The effect on refractive outcome depends on the sequence of surgeries. Better refractive outcome is achieved if phacoemulsification is performed after trabeculectomy.

Evolving Surgical Interventions in the Treatment of Glaucoma

Interventions in the treatment of mild to moderate glaucoma have evolved to include a group of procedures collectively named "Minimally Invasive Glaucoma Surgery (MIGS)." These procedures are less invasive than traditional filtering surgery and setons and offer the benefit of an improved side-effect profile. A review of current published literature has shown that these procedures offer lower intraocular pressure, decrease reliance on topical medications, have no negative effect on refractive outcomes, and can be safely done following failed tube surgery.

Effect of trabeculectomy on the accuracy of intraocular lens calculations in patients with open-angle glaucoma

BACKGROUND

The objective of the study is to examine the effect of trabeculectomy on intraocular lens power calculations in patients with open-angle glaucoma (OAG) undergoing cataract surgery.

DESIGN

The design is retrospective data analysis.

PARTICIPANTS

There are a total of 55 eyes of 55 patients with OAG who had a cataract surgery alone or in combination with trabeculectomy.

METHODS

We classified OAG subjects into the following groups based on surgical history: only cataract surgery (OC group), cataract surgery after prior trabeculectomy (CAT group), and cataract surgery performed in combination with trabeculectomy (CCT group).

MAIN OUTCOME MEASURES

Differences between actual and predicted postoperative refractive error.

RESULTS

Mean error (ME, difference between postoperative and predicted SE) in the CCT group was significantly lower (towards myopia) than that of the OC group (P = 0.008). Additionally, mean absolute error (MAE, absolute value of ME) in the CAT group was significantly greater than in the OC group (P = 0.006). Using linear mixed models, the ME calculated with the SRK II formula was more accurate than the ME predicted by the SRK T formula in the CAT (P = 0.032) and CCT (P = 0.035) groups.

CONCLUSIONS

The intraocular lens power prediction accuracy was lower in the CAT and CCT groups than in the OC group. The prediction error was greater in the CAT group than in the OC group, and the direction of the prediction error tended to be towards myopia in the CCT group. The SRK II formula may be more accurate in predicting residual refractive error in the CAT and CCT groups.

One Year of Glaucoma Research in Review-2013 to 2014

PURPOSE

The purpose of this study was to provide the practicing clinical ophthalmologist with an update on relevant glaucoma literature published from 2013 to 2014.

DESIGN

This study is a literature review.

METHODS

The authors conducted a 1-year (October 1, 2013, to September 30, 2014) English-language glaucoma literature search on PubMed of articles containing "glaucoma" or "glaucomatous" with title/abstract as a filter. Medical subject headings filtered searching was not performed because of the newness of the reviewed material.

RESULTS

Literature search yielded 2314 articles, after which we excluded reviews and letters to the editor. We highlighted articles featuring new or updated approaches to the pathophysiology, diagnosis, or treatment of glaucoma and gave preference to human research.

CONCLUSIONS

This review features literature that is of interest to ophthalmologists in practice and also highlights studies that may provide insight on future developments applicable to clinical ophthalmology.

Comparison of surgical outcomes after phacotrabeculectomy in primary angle-closure glaucoma versus primary open-angle glaucoma

PURPOSE

To compare postoperative outcomes and assess factors associated with intraocular pressure (IOP) reduction after phacotrabeculectomy in patients with primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG).

METHODS

This is a retrospective study of patients who underwent phacotrabeculectomy between 2010 and 2013. Factors including age, gender, visual field (VF), the number of glaucoma medications used, biometric changes, IOP, and surgical success rates were compared between groups.

RESULTS

There were 27 PACG and 34 POAG patients. The PACG group had a greater mean IOP reduction after phacotrabeculectomy compared to the POAG group (5.5 ± 7.9 mmHg versus 2.0 ± 4.2 mmHg; p = 0.03). However, the final mean IOP was similar between the two groups (PACG: 12.2 ± 4.8 mmHg, POAG: 12.3 ± 3.1 mmHg; p = 0.92). Phacotrabeculectomy resulted in a mean decrease in axial length (AL) of 0.16 ± 0.15 mm in PACG and 0.16 ± 0.11 mm in POAG (p = 0.96), and an increase in anterior chamber depth (ACD) of 1.41 ± 0.91 mm in PACG, and 0.87 ± 0.86 mm in POAG (p = 0.04). At 2 years follow-up, the cumulative success rate of phacotrabeculectomy was 74% in PACG and 62% in POAG. Multivariate analysis found that early glaucoma stage, greater postoperative increase in ACD, and high preoperative IOP were factors associated with greater IOP reduction.

CONCLUSION

Postoperative success rates and mean IOP on the final visit after phacotrabeculectomy were similar between the PACG and POAG groups. Factors associated with IOP reduction were greater postoperative increase in ACD, and high preoperative IOP.

Refractive and visual outcomes after combined cataract and trabectome surgery: a report on the possible influences of combining cataract and trabectome surgery on refractive and visual outcomes

PURPOSE

To compare combined trabectome-cataract surgery with cataract-alone surgery regarding their refractive and visual outcomes and complications.

METHODS

In 137 eyes that underwent combined trabectome-cataract surgery, the postoperative refraction error and best visual acuity after at least 2 months postoperatively were compared to those of an in-house control group of 1,704 eyes that underwent outpatient cataract surgery.

RESULTS

Combined trabectome-cataract surgery showed no significant differences regarding the biometry prediction error (BPE, mean 0.53 D vs. 0.48 D, p = 0.24) or visual outcome (BCVA, 0.81 vs. 0.78, p = 0.06). The rate of postoperative cystoid macular edema was slightly higher in the combined surgery group (2.2 % vs. 1.9 %).

CONCLUSIONS

Refractive and visual outcomes were similar in both groups. Despite the slightly higher rate of postoperative macula edema, we were able to observe that the combination of these two procedures is a feasible method in glaucoma and cataract surgeries.