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

Changes in Intraocular Pressure and Anterior Chamber Parameters Following Cataract Surgery, Vitrectomy, and Combined Surgery

PURPOSE

The aim of this study is to investigate changes in intraocular pressure (IOP) and anterior-segment parameters before and after cataract surgery, vitrectomy, and combined surgery.

METHODS

The records of patients who had undergone cataract surgery (cataract group), vitrectomy (vitrectomy group), or combined cataract surgery and vitrectomy (combined group) at our hospital were retrospectively examined. The vitrectomy group consisted of pseudophakic eyes. IOP and anterior-segment measurements, including anterior chamber depth (ACD), angle opening distance (AOD), trabecular-iris angle (TIA), and trabecular-iris space area (TISA), were measured using swept-source anterior-segment optical coherence tomography before and 6 months after surgery in 41, 15, and 40 eyes, respectively.

RESULTS

In the cataract and combined groups, there was a decrease in IOP (cataract group: from 15.8 to 13.4 mmHg, p <0.001; combined group: from 15.8 to 14.2 mmHg, p = 0.002) and an increase in the central corneal thickness after surgery (p <0.001). The ACD increased in all groups, with a smaller increase in the vitrectomy group (p <0.03). Postoperative AOD, TIA, and TISA were significantly increased in the cataract and combined groups (p <0.02). Higher preoperative IOP and larger IOP reduction after surgery were correlated with smaller preoperative AOD, TISA, and TIA in cataract and combined groups (p <0.034). A small preoperative ACD was related to smaller preoperative AOD, TISA, TIA (r > 0.649, p <0.001), and postoperative IOP reduction in the cataract and combined groups (r = 0.377, p = 0.018 and r = 0.559, p = 0.001, respectively).

CONCLUSIONS

Compared to the vitrectomy group, the cataract and combined groups showed reduced postoperative IOP and increased AOD, TISA, and TIA. In these two groups, patients with shallower preoperative ACDs showed greater changes in IOP after surgery. Changes in IOP after surgery are thought to be related to changes in the anterior segment caused by the removal of the crystalline lens.

Imaging analysis of the biological parameters of the lens in patients with cortical age-related cataracts using ultrasound biomicroscopy

BACKGROUND

The spatial position of the lens in patients with cortical age-related cataract (CARC) is unclear. We investigated a basis for the assessment of visual quality after cataract surgery by analysing the ultrasound biomicroscopic characteristics of the biological parameters of the lens in patients with CARC.

METHODS

In this retrospective study, 119 patients (50 males and 69 females, totalling 238 eyes) with CARC who underwent simple cataract surgery were selected. The lens thickness (LT), axial length (AL), anterior chamber depth (ACD), lens vault (LV), trabecular-iris angle (TIA), iris-lens angle (ILA), iris-lens contact distance (ILCD) were measured by A-scan ultrasound and ultrasound biomicroscopy. The corresponding lens position (LP) and relative lens position (RLP) were calculated.

RESULTS

LP was greater in men than in women (P < 0.05), LV was smaller in men than in women (P = 0.002), ILA and ILCD were not statistically significant (P = 0.072 and P = 0.854, respectively). There were significant differences in TIA, ILA, and ILCD in the four quadrants (all P < 0.05), with a trend in the distribution of TIA: superior < inferior < nasal < temporal, ILA: nasal < inferior < temporal < superior, and ILCD: superior < temporal < inferior < nasal.

CONCLUSIONS

The lens protrudes more obviously in females than in males and the lens tilts to a certain extent with the increase of age and tends to be more upward and temporal in the supine position. Therefore, trends in lens-related parameters in patients with CARC should be taken seriously.

Anterior Segment Characteristics of Eyes with Anterior Chamber Depth Less than 2.8 mm and Axial Length Greater than 25 mm

INTRODUCTION

This study aimed to investigate anterior segment parameters of eyes, with anterior chamber depth (ACD) less than 2.8 mm and axial length greater than 25.0 mm.

METHODS

This cross-sectional study included 180 myopic eyes of 180 consecutive patients with axial length greater than 25.0 mm. Patients were divided into low ACD (ACD < 2.8 mm, n = 56) and normal ACD (ACD ≥ 2.8 mm, n = 124) groups. Anterior segment parameters were measured using Scheimpflug imaging and ultrasound biomicroscopy. A general linear model was used to compare parameters between the two groups, after adjusting for age and spherical equivalent.

RESULTS

Compared with the normal ACD group, the low ACD group had lower values for the following parameters: corneal diameter, trabecular-anterior iris surface angle, angle-opening distance at 500 μm, anterior chamber volume, anterior chamber width, anterior vault, iris thickness at 500 μm, ciliary sulcus-to-sulcus diameter, distance between cornea and sulcus, trabecular-ciliary process distance, maximum ciliary body thickness, ciliary process length, relative anterior vault, relative distance between cornea and sulcus, and relative lens position (general linear model, p < 0.05). In contrast, central corneal thickness, iris curvature, lens thickness, lens vault, and iris-ciliary angle were greater in the low ACD group (general linear model, p < 0.05).

CONCLUSION

A smaller anterior segment, as well as a thicker and more anteriorly positioned lens, may correlate with shallow ACD in eyes with long axial length.

Effect of Conventional Cataract Surgery and Femtosecond Laser-Assisted Cataract Surgery on Bruch's Membrane Opening-Minimum Rim Width, Retinal Nerve Fiber Layer, and Macular Thickness

Purpose

To evaluate the effect of conventional cataract surgery (CCS) and femtosecond laser-assisted cataract surgery (FLACS) on Bruch's membrane opening-minimum rim width (BMO-MRW), peripapillary retinal nerve fiber layer thickness (RNFL), and macular thickness (MT) using spectral-domain optical coherence tomography (SD-OCT).

Methods

BMO-MRW, RNFL, and MT were measured using SD-OCT preoperatively, 1 month and 6 months after surgery in both CCS and FLACS groups. Differences between preoperative and postoperative values were evaluated in both groups. The postoperative changes were evaluated in each group and compared between groups.

Results

A total of 146 eyes of 146 patients were included in this study, 65 underwent CCS, and 81 underwent FLACS. One month after surgery, there was an increase (in microns) of 20.93 in BMO-MRW, 4.26 in RNFL, and 7.85 in MT in CCS group (P < 0.001), and 17.7, 3.73, and 5.65, respectively, in FLACS group (P < 0.001). Six months after surgery, there was an increase of 12.53 in BMO-MRW, 1.42 in RNFL, and 4.72 in MT in CCS group (P < 0.001), and 13.7, 1.88, and 4.14, respectively, in FLACS group (P < 0.001). The postoperative changes in CCS group were similar to those in FLACS group.

Conclusion

CCS as well as FLACS result in a slight increase in BMO-MRW, RNFL, and MT values one month and six months after surgery. Neither CCS nor FLACS lead to a deterioration in the parameters that define the structure of the optic nerve head and the macula. These results suggest that FLACS is as safe as CCS regarding the optic nerve head and the macula in normal eyes.

Changes in Macular Thickness after Cataract Surgery in Patients with Open Angle Glaucoma

BACKGROUND

The purpose of this study was to examine the changes in IOP, total macular and RNFL, ganglion cell layer (GCL) thickness, and aqueous humour flare in open angle glaucoma (OAG) patients before and 6 months after cataract surgery.

METHODS

This was a prospective observational case-control age- and gender-matched study. Groups: 40 subjects in a controlled OAG (OAG_c) group, 20 subjects in an uncontrolled OAG (OAG_u) group, and 60 control group subjects.

EXAMINATION

complete ophthalmic evaluation, IOP measurement, anterior and posterior segment Optical Coherence Tomography (OCT), and laser flare photometry before and 6 months postoperatively.

RESULTS

Six months postoperatively IOP decreased in all groups. An increase in macular thickness was found postoperatively in all groups. Preoperative aqueous humour flare was higher in the OAG_c group than in the control group. After cataract surgery, aqueous humour flare was higher in the control group compared to the preoperative result.

CONCLUSIONS

Changes in IOP following cataract surgery were strongly negatively correlated with preoperative IOP. An increase in macular thickness was observed 6 months postoperatively in all groups. Aqueous humour flare did not differ in OAG_c and OAG_u groups pre- and postoperatively but significantly increased in the control group postoperatively.

Impact of Cataract Surgery on IOP and Ocular Structures in Normotensive Patients and Primary and Exfoliation Open-Angle Glaucoma Patients

Purpose

The aim of this study was to evaluate and compare the changes in Intraocular Pressure (IOP) and other ocular parameters: the Anterior Chamber Angle (ACA), Anterior Chamber Volume (ACV), and Anterior Chamber Depth (ACD) during phacoemulsification surgery in Greek patients with normotensive eyes and those with well-controlled Open-Angle Glaucoma (OAG). Additionally, parameters such as the Corneal Thickness (CCT), Axial Length (AL), Central Macular Thickness (CMT), and Retinal Nerve Fibre Layer (RNFL) were also examined.

Patients and Methods

This was a prospective observational case-control study that included 50 phakic eyes, 25 normotensive (Group 1), and 25 with OAG: 15 Primary Open-Angle Glaucoma (POAG) and 10 Exfoliation Glaucoma (EXG) (Group 2). Ophthalmic assessment included IOP measurements, ocular biometry, and anterior and posterior segment optical coherence tomography evaluation of the aforementioned ocular parameters, prior and 6 months after phacoemulsification surgery.

Results

At the 6 months post-operative review, a greater IOP reduction was recorded in eyes with OAG, in comparison to normotensive ones (5.3mmHg and 1.6 mmHg respectively). In addition, a significant but similar increase was recorded in the values of the ACA, ACV, and ACD of both groups between the pre- and the post-op period. Furthermore, the CCT and AL values remained unaltered. Finally, there was a non-statistically significant change in the mean CMT and the mean average RNFL of both groups.

Conclusion

Eyes with OAG tend to undergo a greater reduction in IOP post-phacoemulsification surgery, in comparison to normotensive eyes. This reduction may not be solely attributed to ocular anatomical changes after phacoemulsification surgery but may also be due to the remodeling of the trabecular meshwork and the ciliary body. This may be especially true in the case of OAG eyes, which already start off with a compromised trabecular endothelium prior to surgery.

A comparison of lens parameters in patients with various subtypes of primary angle-closure disease and the normal population: A prospective study

Purpose:

To assess the role of lens parameters in the detection and progression of primary angle-closure disease (PACD) by combining A-scan and A-scan optical coherence tomography (AS-OCT) parameters.

Methods:

A cross-sectional study was conducted in a tertiary health-care center in eastern India. A total of 91 study subjects including cases and controls were included in the study. The parameters studied were lens thickness (LT), lens axial factor (LAF), relative lens position (RLP), and lens vault (LV). Anterior chamber depth (ACD) and axial length (AL) were also analyzed using A-scan.

Results:

The LT was significantly more in all subtypes of PACD (from 4.24 ± 0.84 to 5.02 ± 0.18 mm) than in controls (4.04 ± 0.46 mm; P < 0.01). Similarly, LAF was significantly less among all subtypes of PACD compared to controls (P < 0.001). The RLP, calculated using the formula (ACD + 0.5 LT)/AL × 10, showed no significant difference (P > 0.05) between various study groups. The LV in acute angle-closure glaucoma (AcCG) patients was significantly higher compared to the control population (P < 0.01). Ocular parameters like ACD decreased, whereas LT and LAF increased from normal through primary angle closure (PAC) to primary angle-closure glaucoma (PACG). Logistic regression analysis found a significant association between a decrease in ACD and an increased risk of PACG (P-value was 0.0001) and an increase in LT and LAF with increased risk of PACG (P = 0.040 and P = 0.006, respectively).

Conclusion:

Inclusion of lens parameter assessment in the workup of a patient with PACD helps in detection and close monitoring of the progression from suspected to disease state.

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.

The change of anterior chamber angle parameters after cataract surgery in diabetic patients

Purpose:

The purpose of this study is to investigate the change of anterior chamber angle morphology after cataract surgery in patients with type 2 diabetes mellitus (DM2) using anterior segment optical coherence tomography (AS-OCT).

Methods:

In this prospective and comparative study, 57 eyes of the patients with cataract were investigated. The patients were divided into two groups. The DM2 group included cataractous type 2 diabetic patients without diabetic retinopathy (n = 30) and the non-DM2 group included nondiabetic participants with cataract (n = 27). The AS-OCT examinations were performed at baseline and 1 month after the cataract surgery. The corrected distance visual acuity (CDVA), intraocular pressure (IOP), angle-opening distance at 500 µm (AOD-500) and trabecular iris space area at 500 µm (TISA-500), and scleral spur angle (SSA) in temporal quadrant were analyzed.

Results:

The mean age, sex, and axial length values were similar in both groups (p > 0.05 for all). The CDVA was significantly improved in both groups (p < 0.001). The mean AOD-500, TISA-500, and SSA were increased and the mean IOP was decreased after cataract surgery in both groups (p < 0.001 for all). There were not any statistically significant intergroup differences in CDVA, IOP, and AS-OCT measurements between the DM2 and non-DM2 groups (p > 0.05 for all).

Conclusion:

Cataract surgery showed significant increases in mean anterior chamber angle parameters and reductions in IOP values in both diabetic and nondiabetic patients without intergroup significant differences. These results suggested the safety and effectiveness of cataract surgery, especially regarding anterior chamber angle parameters and so IOP changes.

Changes in ocular morphology after cataract surgery in open angle glaucoma patients

The purpose of this study was to evaluate intraocular pressure (IOP) pre- and postoperatively, together with anterior chamber angle (ACA) parameters and biometrical results in cataract patients with or without open angle glaucoma (OAG). The prospective observational case-control study included 15 eyes with cataract and OAG in the glaucoma group and 25 eyes with only cataract in control group. Examination included full ophthalmic evaluation, IOP, ocular biometry and anterior segment optical coherence tomography measuring ACA pre- and 6 months postoperatively. OAG patients had a larger absolute IOP reduction compared to control group. Anterior chamber depth (ACD) and ACA width significantly increased in both groups. The OAG group had a tendency of narrower ACA preoperatively, but overall ACA parameters did not differ in either group pre- and postoperatively. The ACD change after surgery correlated with ACA parameters in the control group, but not in OAG group. Axial length was shorter postoperatively in the control group, but remained similar in the OAG group. Absolute IOP reduction was more pronounced in cataract patients with OAG than in cataract patients without glaucoma. ACD and ACA postoperatively increased in both groups and AL shortening was observed in non-OAG in cataract group.

Anterior segment optical coherence tomography imaging and ocular biometry in cataract patients with open angle glaucoma comorbidity

BACKGROUND

Anterior chamber angle anatomy in perspective of ocular biometry may be the key element to intraocular pressure (IOP) reduction, especially in glaucoma patients. We aim to investigate anterior chamber angle and biometrical data prior to cataract surgery in patients with and without glaucoma comorbidity.

MATERIALS AND METHODS

This prospective comparative case-control study included 62 subjects (38 with cataract only and 24 with cataract and glaucoma). A full ophthalmic examination including, Goldmann applanation tonometry, anterior chamber swept source optical coherence tomography (DRI OCT Triton plus (Ver.10.13)) and swept source optical biometry (IOL Master 700 v1.7) was performed on all participants.

RESULTS

We found that ocular biometry parameters and anterior chamber parameters were not significantly different among groups. However, when we added cut-off values for narrow angles, we found that glaucoma group tended to have more narrow angles than control group. IOP was higher in glaucoma group despite all glaucoma patients having medically controlled IOP. In all subjects, anterior chamber parameters correlated well with lens position (LP), but less with relative lens position, while LP cut-off value of 5.1 mm could be used for predicting narrow anterior chamber angle parameters.

CONCLUSIONS

Cataract patients tend to develop narrow anterior chamber angles. Anterior chamber angle parameters have a positive moderate to strong relationship with lens position. LP may be used predicting narrow angles.

Using machine learning to predict post-operative depth of focus after cataract surgery with implantation of Tecnis Symfony

OBJECTIVE

To predict post-operative depth of focus (DoF) using machine learning techniques after cataract surgery with Tecnis Symfony implantation and determine associated impact factors.

METHODS

This was a retrospective cohort study among patients receiving Tecnis Symfony implantation, an extended-range-of-vision intraocular lens, during October 2016-January 2020 at Daqing Oilfield General Hospital, China. Four different predictive models were used to predict good post-operative DoF (⩾2.5 D): Extreme Gradient Boost (XGBoost), random forest (RF), LASSO penalized regression, and multivariable logistic regression (MLR). Apriori algorithm was employed to further explore the association between patient attributes and DoF.

RESULTS

A total of 182 unique cases (143 patients) were included. The XGBoost model produced the best predictive accuracy compared to RF, LASSO, and MLR models. Overall performance of the best fitting XGBoost model was as follows: accuracy = 70.3%, AUC = 80.2%, sensitivity = 65.5%, and specificity = 87.5%. The Apriori algorithm identified six preoparative attributes with substantial effects on good post-operative DoF: low anterior chamber depth (ACD) (1.9 to <2.5 mm), smaller pupil size (1.7 to <2.5 mm), low-to-mid axial length (21 to <23 mm), minimum astigmatism degree (-0.2 to 0 diopter), low IOP (9 to <12 mmHg), and medium lens target refractive error (-0.5 to <-0.25 diopter).

CONCLUSIONS

Machine Learning models were able to predict good post-operative DoF among cataract patients receiving a Tecnis Symfony ocular lens implantation. The accuracy of the model was above 70%. The Apriori algorithm identified six preoperative attributes with a strong association with post-operative DoF.

Intraocular Pressure Reduction After Real-world Cataract Surgery

PRéCIS:: A large cohort undergoing cataract extraction was retrospectively analyzed to ascertain the degree of real-world intraocular pressure (IOP) reduction in normal eyes and those with glaucoma, and a predictive formula was developed.

PURPOSE

The purpose of this study was to define the real-world degree of IOP reduction after cataract extraction to guide its role as an isolated intervention for glaucoma.

MATERIALS AND METHODS

A retrospective analysis was carried out of clinical data collected in 8 clinical sites in the United Kingdom from an electronic medical record system between January 2006 and May 2015. A total of 20,508 eyes without known pathology and 2251 eyes from patients with glaucoma undergoing phacoemulsification and intraocular lens insertion were included. Eyes with intraoperative complications, undergoing additional procedures, axial lengths outside 22 to 26.5 mm, preoperative IOP under 6 mm Hg or over 30 mm Hg, and copathology, except for amblyopia or glaucoma, were excluded. The main outcome measure was the change in preoperative IOP compared with the next recorded visit for up to 12 weeks.

RESULTS

In eyes without pathology, the mean reduction in IOP was 1.40 mm Hg (±3.74) compared with 1.03 (±5.02), P-value <0.001, in eyes with a diagnosis of glaucoma. A multiple linear regression model identified preoperative IOP, a glaucoma diagnosis, preoperative corrected visual acuity, age, and axial length as determinants of IOP reduction. The model was validated against an independent cohort.

CONCLUSIONS

We quantify mean IOP reduction achieved in a real-world setting from cataract surgery alone. In glaucomatous eyes where angle closure is not differentiated, phacoemulsification alone yields only a modest reduction of IOP.

Analysis of the Effect of Intraocular Lens Implantation on Retinal Nerve and Postoperative Nursing Outcome Based on Ultrasound Imaging

Traumatic cataract is a common complication of ocular contusion. Caused by various forms of trauma, the course and prognosis of traumatic cataract are also different. Intraocular lens (IOL) implantation is the most effective treatment at the present time and can provide good visual quality and near, medium, and far vision. In this study, an adaptive medical ultrasound image denoising algorithm was constructed based on the biological vision mechanism and was applied to observe IOL implantation and postoperative care of 30 patients with traumatic cataract. Results showed that eyesight could be restored to the original healthy state after IOL implantation, and eyesight was close to normal 3 months after surgery. The corresponding noise pixel block of the noise reduction algorithm was obviously the lowest. A total of 30 patients (9 patients with contusion, 13 patients with intraocular foreign body, and 8 patients with perforation) were treated with aspheric and multifocal IOL to achieve the expected outcome. The noise reduction algorithm constructed in this study effectively reduced the speckle noise of ultrasound images, improved the clarity of ultrasound images, and achieved the effective observation of medical nursing outcome after traumatic cataract IOL implantation. After IOL implantation, the retinal nerves of patients with traumatic cataract were affected to different degrees.

Predictors of Intraocular Pressure Lowering after Phacoemulsification and iStent Implantation

PURPOSE

To explore the demographic and clinical variables associated with intraocular pressure (IOP) lowering after cataract extraction (CE) alone or CE in combination with the iStent (Glaukos Corporation) placement (CE+IS).

DESIGN

Retrospective data extraction and survival analysis of consecutive patients identified over a 2-year period.

PARTICIPANTS

Patients with mild to moderate glaucoma who underwent CE (48 eyes of 32 patients) or CE+IS (61 eyes of 37 patients) were analyzed.

METHODS

Inability to reduce the number of medications or the IOP by at least 20% compared with baseline on 2 consecutive visits was considered surgical failure. Using Cox proportional hazards models, survival analysis was performed, and demographic and clinical variables were evaluated as risk factors.

MAIN OUTCOME MEASURES

Time to failure after surgical procedure.

RESULTS

CE+IS had lower odds of failure than CE alone (hazard ratio [HR], 2.01; P = 0.047). In White patients, CE+IS showed greater odds of success compared with CE alone (HR, 2.86; P = 0.007). For non-White patients, no difference was found in the outcomes for the 2 procedures (HR, 0.59; P = 0.48). In the multivariate analysis, non-White race (HR, 8.75; P = 0.0002) and longer axial length (HR, 1.61; P = 0.03) were associated with greater hazard of failure after CE+IS. In the CE group, greater odds of failure were associated with steeper corneal curvature (HR, 1.74; P = 0.008), shallower anterior chamber (HR, 0.22; P = 0.008), and longer axial length (HR, 1.58; P = 0.01).

CONCLUSIONS

Addition of the iStent to CE improved the duration of IOP lowering in White patients, but not in non-White patients. Associations between IOP lowering after CE and biometric parameters may allow for leveraging these clinical parameters for better case selection for these procedures.

Long term outcomes of cataract surgery in severe and end stage primary angle closure glaucoma with controlled IOP: a retrospective study

Background

To investigate the long term surgical outcomes of cataract surgery in severe and end stage glaucoma patients with preoperative intraocular pressure less than 21 mmHg, and to detect the associated factors.

Methods

A retrospective study of primary angle closure glaucoma patients was conducted on who underwent cataract surgery or combined with goniosynechialysis from March 2015 to April 2018. Main outcome measures were visual acuity, intraocular pressure, number of glaucoma medications and complications.

Results

Sixteen patients (19 eyes) were included. The mean age was 64.89 ± 11.68 years and the mean followed up duration was 21.89 ± 7.85 months. The final visual acuity was significantly improved from 0.69 ± 0.55 to 0.46 ± 0.52 logMAR, within 12 (63.2%) eyes improved, 4 (21.1%) eyes kept unchanged, and 3 (15.8%) eyes reduced. Linear regression analysis indicated that higher mean deviation, higher visual field index and lower glaucoma stage associated with better final visual acuity (r = − 0.511, r = − 0.493, r = 0.537 respectively). Moreover, the final number of medications were reduced from 1.26 ± 0.99 to 0.26 ± 0.56 (p < 0.01). The mean intraocular pressure was not significantly reduced with the final IOP of 14.48 ± 3.74 mmHg (p = 0.97). While the eyes with intraocular pressure above 15 mmHg was decreased to 6 (31.6%) eyes compared to 10 (52.6%) eyes at baseline. Moreover, the number of eyes free of medications was increased from 4 (21.1%) preoperatively to 15 (78.9%) eyes postoperatively.

Conclusions

Final visual acuity was significantly improved in the severe and end stage primary angle closure glaucoma patients and the number of eyes came off medications increased by 57.8% after cataract surgery. Preoperatively, the glaucoma stage, mean deviation and visual field index are important parameters to predict the final visual acuity after cataract surgery.

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.

Changes in intraocular pressure after intraocular eye surgery-the influence of measuring technique

AIM

To investigate the changes in intraocular pressure (IOP) before and after intraocular surgery measured with Goldmann applanation tonometry (GAT) and pascal dynamic contour tonometry (PDCT), and assessed their agreement.

METHODS

Patients who underwent trans pars plana vitrectomy (TPPV) with or without cataract extraction (CE) were included. The IOP was measured in both eyes with GAT and PDCT pre- and postoperatively, where the non-operated eyes functioned as control.

RESULTS

Preoperatively, mean IOP measurements were 16.3±6.0 mm Hg for GAT and 12.0±2.8 mm Hg for PDCT for the operated eyes. Postoperatively, the mean IOP dropped to 14.3±5.6 mm Hg for GAT (P=0.011) and rose up to 12.7±2.6 mm Hg for PDCT (P=0.257). Bland-Altman analysis showed a poor agreement between GAT and PDCT with a mean difference of 2.9 mm Hg preoperatively and 95% limits of agreement ranging from -3.2 to 9.0 mm Hg. Postoperatively, the mean difference was 1.2 mm Hg with 95% limits of agreement ranging from -8.3 to 10.7 mm Hg. There were no significant differences between the TPPV and TPPV+CE group, except when measured with PDCT postoperatively (P=0.012).

CONCLUSION

The IOP is reduced after surgery when measured with GAT and remained stable when measured with PDCT. However, the agreement between GAT and PDCT is poor. Although PDCT may be a more accurate predictor of the true IOP, it seems less suitable for daily use in the clinical practice.

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.

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.

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.

Effect of pupil dilation on biometric measurements and intraocular lens power calculations in schoolchildren

Purpose

To investigate the effect of pupil dilation on ocular biometric parameters and intraocular lens (IOL) power calculation in schoolchildren using the Lenstar LS 900.

Methods

One hundred forty eyes of 140 healthy schoolchildren were included in the analysis. Axial length (AL), central corneal thickness (CCT), aqueous depth (AD), anterior chamber depth (ACD), lens thickness (LT), flat keratometry (K), steep K, astigmatism, white-to-white (WTW), and iris/pupil barycenter distance were measured, before and after pupil dilation. Anterior segment length (ASL) was defined as the sum of ACD and LT, and lens position (LP) was defined as ACD plus half of the LT. The relative lens position (RLP) was defined as LP divided by AL. IOL power was calculated using the eight formulas (Hill-RBF, Barrett, Haigis, Hoffer Q, Holladay, Olsen, SRK II, and SRK/T) integrated in the Lenstar LS 900. Parameters before and after pupil dilation were compared.

Results

AL, AD, ACD, LT, ASL, LP, RLP, flat K, iris barycenter distance, pupil barycenter distance, and PD differed significantly after pupil dilation (P < 0.001 in all cases), as compared to before dilation. The Olsen formula demonstrated significant differences in the magnitude of astigmatism (P = 0.010) and IOL power (P = 0.003) after pupil dilation. Using the different formulas, 23.6–40.7% of participants had IOL power changes of more than 0.50 diopters, while 0.7–1.4% had IOL changes of more than 1.0 diopter after pupil dilation.

Conclusions

Dilated and undilated pupil size affected the Lenstar LS 900 measurement of some ocular biometric parameters, and pupil dilation led to IOL power changes exceeding 0.50 diopters with a high percentage (from 23.6% to 40.7%) in schoolchildren, which should be noticed in clinical practice.

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.

Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma

PURPOSE

To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes.

DESIGN

Prospective, cross-sectional clinical study.

METHODS

Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects.

RESULTS

The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008).

CONCLUSION

In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders.

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.

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.

Ethnic differences in lens parameters measured by ocular biometry in a cataract surgery population

Purpose

To investigate whether differences exist in lens position and other lens parameters among major ethnic groups with cataractous eyes, which may help explain racial differences in angle closure risk.

Methods

This retrospective, cross-sectional study included 807 adult patients who had cataract surgery between years 2014 and 2016 at the University of California, San Francisco (UCSF). Adult patients of white, Asian, Hispanic and African-American ethnicity were included. Lens position (LP), defined as anterior chamber depth (ACD) + 1/2 lens thickness (LT), was assessed using measurements from optical biometry. Other assessed biometric parameters included axial length (AL), relative lens position (RLP) (defined as LP/AL), and anterior chamber depth (ACD).

Results

A total of 807 patients and 1361 eyes were included in this study from a database of patients having cataract surgery. Mean age was 69.2 years (age range from 18 to 101 years old), and 60.3% of patients were women. The mean LP measurements were 5.54±0.32 mm for white, 5.38±0.32 mm for Asian, 5.32±0.30 mm for Hispanic, and 5.40±0.28 mm for African-American participants. After adjusting for age, sex, and AL, significant differences were found when comparing LP in paired comparisons among White cohort with Asians (P<0.001), Hispanics (P<0.001) and African-Americans (P = 0.003). Additionally, when comparing RLP, similar significant results were found when comparing Whites with Asians (P<0.001), Hispanics (P<0.001) and African-Americans (P = 0.002). Lastly, pair-wise comparison of LT between ethnic groups showed significant differences while comparing Asians with Whites (P = 0.001) and Asians with African-Americans (P<0.001).

Conclusion

The results of this study suggest that the LP of Hispanic, Asian, and African-American patients are significantly smaller than that of White patients, and among all ethnic groups, Hispanics and after Asians have the smallest LP (P<0.001) and RLP (P<0.001). These findings may have implications for the relative risk of angle closure and the potential IOP response after cataract surgery among different ethnic groups.