Phacoemulsification versus combined phacotrabeculectomy in medically controlled chronic angle closure glaucoma with cataract

Effect of Phacoemulsification on Intraocular Pressure in Healthy Subjects and Glaucoma Patients

BACKGROUND

We investigated how cataract surgery might influence long-term intraocular pressure (IOP) change in both healthy subjects and glaucoma patients.

METHODS

A retrospective analysis of patients who had had clear corneal phacoemulsification with a minimum of 12 months of follow up was performed. Glaucoma patients with medically controlled open-angle glaucoma and healthy subjects with no glaucoma were included in the analysis. The change of IOP after phacoemulsification and factors associated with postoperative IOP change were investigated.

RESULTS

In total, 754 eyes of 754 patients, specifically 106 patients with glaucoma and 648 patients with no glaucoma (i.e., healthy subjects) were enrolled. The phacoemulsification effected a reduction of IOP: 1.03 ± 3.72 mmHg in healthy subjects and 1.08 ± 3.79 mmHg in glaucoma patients at postoperative 1 year (P = 0.656). There were negative coefficients of IOP until 1 year of follow up (all P < 0.001), but the IOP change gradually showed a less steeply decreasing slope (correlation coefficient: -0.993), compared with those for 1 week and 1 month of follow up (correlation coefficients: -1.893 and -1.540, respectively). In the multivariate analysis, age and preoperative IOP showed significant associations with postoperative IOP change (regression coefficients: -0.034 and 0.419 respectively, all P < 0.001).

CONCLUSION

Phacoemulsification resulted in IOP reduction, which effect regressed in healthy subjects and glaucoma patients over the course of long-term follow up. Therefore, long-term monitoring of IOP change is needed. In cases of higher preoperative IOP and young patients, phacoemulsification alone is a reliable option for IOP control.

Comparative Clinical Study of Medically Controlled Nonsevere Chronic Primary Angle-closure Glaucoma with Coexisting Cataract Surgically Managed by Phacoemulsification as against Combined Phacotrabeculectomy

PURPOSE:

Comparative clinical study of medically controlled non-severe chronic Primary Angle Closure Glaucoma (PACG) with co-existing cataract surgically managed by phacoemulsification as against combined phacotrabeculectomy.

METHODS:

This randomized clinical trial was conducted between December 2011 and December 2013. Patients were randomly assigned to Phacoemulsification (PE) and Phacotrabeculectomy (PT) groups for surgery. Intraocular pressure, anti-glaucoma medications, Best Corrected Visual Acuity, anterior chamber angle widening and post-operative complications in both groups were compared after 12 months.

RESULTS:

There were 46 eyes with PACG in PE group and 45 in PT group. The IOP at 12 months in PE group was 11.5±1.3mmHg and 11.8±1.2mmHg in PT gr. (p = 0.28). The eyes requiring single anti-glaucoma medications at 12months in PE group was 0, PT group was 1 (p = 0. 495). The post op BCVA at 12months in PE group 0.3+-0.12 and 0.33±0.15 in PT group (p = 0.22). 3 cases in PT group required additional intervention whereas no additional intervention was required in PE group and this difference was statistically significant (p = 0.116).

CONCLUSION:

Phacoemulsification is equally effective in terms of intraocular pressure control and visual outcome as phacotrabeculectomy with better safety and less post-operative complication.

Efficacy of Cataract Surgery With Trabecular Microbypass Stent Implantation in Combined-Mechanism Angle Closure Glaucoma Patients

PURPOSE

To evaluate the effectiveness of trabecular microbypass stent (iStent) implantation in combined mechanism glaucoma (CMG).

DESIGN

Retrospective cohort study.

METHODS

We reviewed the medical charts of patients with the following scenarios: (1) primary open-angle glaucoma (POAG) undergoing phacoemulsification (PE), (2) POAG undergoing PE with iStent (POAG-PE/iStent), (3) CMG undergoing PE (CMG-PE), and (4) CMG undergoing PE with iStent (CMG-PE/iStent). CMG was defined as narrow-angle glaucoma patients whose angle had opened after iridotomy. Linear mixed-effects models were performed to determine the effect of iStent on postoperative 1-year success rate (intraocular pressure [IOP] ≤ 18 without medication), IOP, and number of medications.

RESULTS

Data from 301 eyes were available. The number of eyes (subjects) was 61 (45) in the POAG-PE, 60 (50) in POAG-PE/iStent, 93 (76) in CMG-PE, and 87 (70) in CMG-PE/iStent group. Success criteria were achieved in 13.1% for POAG-PE, 33.3% for POAG-PE/iStent (POAG-PE vs POAG-PE/iStent B 3.01; P < .001), 37.6% for CMG-PE, and 43.7% for CMG-PE/iStent (CMG-PE vs CMG-PE/iStent B 2.25; P < .001). There was no difference in the IOP between POAG-PE and POAG-PE/iStent, and between CMG-PE and CMG-PE/iStent. The iStent significantly reduced number of medications in the POAG (B -0.70; P < .001) and CMG group (B -0.52; P < .001). Comparing the effect of iStent on POAG and CMG, the analysis showed similar iStent efficacy in terms of the success rate, IOP, and number of medications (P > .05).

CONCLUSIONS

Combined PE/iStent significantly increased success rate and reduced number of medications in CMG patients compared to PE alone. The effects of iStent were comparable between POAG and CMG groups.

Contemporary approach to the diagnosis and management of primary angle-closure disease

The primary angle-closure disease spectrum varies from a narrow angle to advanced glaucoma. A variety of imaging technologies may assist the clinician in determining the pathophysiology and diagnosis of primary angle closure, but gonioscopy remains a mainstay of clinical evaluation. Laser iridotomy effectively eliminates the pupillary block component of angle closure; however, studies show that, in many patients, the iridocorneal angle remains narrow from underlying anatomic issues, and increasing lens size often leads to further narrowing over time. Recent studies have further characterized the role of the lens in angle-closure disease, and cataract or clear lens extraction is increasingly used earlier in its management. As a first surgical step in angle-closure glaucoma, lens extraction alone often effectively controls the pressure with less risk of complications than concurrent or stand-alone glaucoma surgery, but may not be sufficient in more advanced or severe disease. We provide a comprehensive review on the primary angle-closure disease nomenclature, imaging, and current laser and surgical management.

Comparison of surgical outcome of trabeculectomy and phacotrabeculectomy in Chinese glaucoma patients

Our study retrospectively reviewed the surgical outcomes up to 3mo of 38 consecutive Chinese glaucoma patients who underwent trabeculectomy (n=18) or phacotrabeculectomy (n=20). Baseline age, visual acuity, and intraocular pressure were comparable. Intraocular pressure from post-operative 1d to 3mo were similar between 2 groups. Complete success was achieved in 65% of phacotrabeculectomy, and 66.7% of trabeculectomy cases; while failure occurred in 16.7% of phacotrabeculectomy, and 10% of trabeculectomy cases at 3mo. Phacotrabeculectomy group consistently showed better improvement in visual acuity. Diffuse blebs occurred in 65% of phacotrabeculectomy and 83% of trabeculectomy eyes; and flat blebs in 35% of phacotrabeculectomy, but none after trabeculectomy. There was more hypotony (5% vs 0) after phacotrabeculectomy. To conclude, phacotrabeculectomy and trabeculectomy demonstrated comparable intraocular pressure control up to 3mo post-operatively. However, phacotrabeculectomy patients had better visual acuity improvement. Nonetheless, more diffuse bleb and less hypotony were present following trabeculectomy.

Proportion of undetected narrow angles or angle closure in cataract surgery referrals

OBJECTIVE

To determine the proportion of patients referred for cataract surgery consultation who had undetected narrow angles (primary angle closure suspect [PACS], primary angle closure [PAC], or primary angle closure glaucoma [PACG]).

DESIGN

Retrospective chart review.

PARTICIPANTS

Phakic patients referred by eye care providers (optometrists and ophthalmologists) to a tertiary centre for cataract management between July 1, 2010 and June 30, 2012 were identified and reviewed.

METHODS

Demographic, referral, and specialist assessment information, as well as biometric data, including anterior segment optical coherence tomography, were collected. Patients with undetected narrow angles were identified. Univariate tests and multivariable analyses were performed to determine risk factors for narrow angles or angle closure.

RESULTS

A total of 1229 patients were included. The mean patient age was 67.8 ± 13.0 years, 53.9% of patients were female, and 26.8% were Asian or South Asian. Of the sample population, 139 (11.3%) patients had PACS, 7 (0.6%) had PAC, and 12 (1.0%) had PACG. Overall, 158 (12.9%) patients had narrow angles or angle closure. Multivariable logistic regression using generalized estimating equations confirmed 3 independent predictors of PACS/angle closure: Asian race (odds ratio 2.82, p < 0.001), shorter axial length (AL) (odds ratio 1.25, p = 0.03), and smaller anterior chamber depth (ACD; odds ratio 33.3, p < 0.001). A patient of Asian race referred for cataract surgery with ACD <2.8 mm and AL <23 mm had a 52% probability of having PACS/angle closure (range 42%-62%) versus 3% if these 3 factors were not present.

CONCLUSIONS

Of patients referred for cataract surgery, 1.5% were found to have undetected narrow angles or angle closure, implying that gonioscopy may not be adequately performed in this patient population.

Aqueous outflow facility after phacoemulsification with or without goniosynechialysis in primary angle closure: a randomised controlled study

BACKGROUND

Goniosynechialysis (GSL) to remove peripheral anterior synechiae (PAS) alongside standard cataract surgery has potential theoretical advantages, Published randomised trials, however, have not shown conclusive functional benefits and aqueous outflow changes following GSL are unknown. This study aimed to compare electronic Shiøtz tonographic aqueous outflow facility (TOF) following phacoemulsification with or without GSL in patients with primary angle closure (PAC) and PAC glaucoma. Secondary outcomes were changes in intraocular pressure (IOP) and use of glaucoma medications.

METHODS

Prospective randomised pilot study of 26 patients on glaucoma medication, with ≥90° PAS and significant lens opacity. Patients were randomised 1:1 to receive phacoemulsification with intraocular lens (IOL) implantation only (phaco) or phacoemulsification with IOL plus GSL (phaco-GSL).

RESULTS

Fourteen patients were randomised to phaco-GSL and 12 to phaco alone. TOF increased with phaco-GSL from 0.099±0.07 μL/min/mm Hg to 0.194±0.07, μL/min/mm Hg, p=0.0006, while the phaco group showed no significant change. IOP reduced in both groups, but reduced significantly more following phaco-GSL (46.0%) compared with phaco alone (27.6%, p=0.04). Medication use and extent of PAS only reduced with phaco-GSL, from 0.923±0.86 to 0.384±0.18 medications, p=0.0279, and from 249.2±83.4 to 110.8±53.9° PAS, 6 months postoperatively. No serious adverse events occurred in either group.

CONCLUSIONS

Eyes randomised to both surgical groups had similar and good outcomes at 6 months in this pilot study. However, only eyes undergoing GSL combined with standard phacoemulsification had significantly increased TOF, reduced glaucoma medication dependence and PAS postoperatively. GSL should therefore be considered in such patients.

TRIAL REGISTRATION NUMBER

NCT00719290, Results.

Phacoemulsification versus combined phacotrabeculectomy in the treatment of primary angle-closure glaucoma with cataract: a Meta-analysis

AIM

To compare the efficacy and safety of phacoemulsification (Phaco) against combined phacotrabeculectomy (Phacotrabe) in primary angle-closure glaucoma (PACG) with coexisting cataract.

METHODS

By searching electronically the PubMed, EMBASE, Scientific Citation Index and Cochrane Library published up from inception to January 2014, all randomized controlled trials that matched the predefined criteria were included. The quality of included trials was evaluated according to the guidelines developed by the cochrane collaboration. And the outcomes estimating efficacy and safety of two different surgical treatments were measured and synthesised by RevMan 5.0.

RESULTS

Five randomized controlled trials were selected and included in Meta-analysis with a total of 468 patients (468 eyes) with both PACG and cataract. We found that Phacotrabe had a greater intraocular pressure (IOP) lowing effect [preoperative IOP: weighted mean difference (WMD)=0.58, 95% confidence intervals (95% CI, -0.53 to 1.69), P=0.31; postoperative IOP: WMD=1.37, 95% CI (0.45 to 2.28), P=0.003], a lower number of anti-glaucoma medications [ risk ratio (RR) =0.05, 95% CI (0.02 to 0.18), P<0.00001] needed postoperatively and less serious damage of optic nerve [risk ratio (RR)=0.48, 95% CI (0.21 to 1.07), P=0.07], but a higher risk of complications [odds ratio (OR) =0.04, 95% CI (0.01 to 0.16), P<0.00001] compared with Phaco. The rest studies indicated that there had no significantly difference between the two surgical methods for postoperative best-corrected visual acuity (BCVA) [WMD=-0.05, 95% CI (-0.14 to 0.05), P=0.32] and loss of visual field [OR=1.06, 95% CI (0.61 to 1.83), P=0.83].

CONCLUSION

Phaco alone compared with Phacotrabe had a better effect in IOP reduction, whereas the security decline. Considering the number of sample size, our results remains to be further studied.

Managing Primary Angle Closure Glaucoma - The Role of Lens Extraction in this Era

Trabeculectomy has been the gold standard in reducing intraocular pressure (IOP) in glaucoma patients, no matter it is angle closure or open angle glaucoma. However in primary angle closure glaucoma, no matter the lens is cataractous or not, it is likely to be pathological, this thicker than usual lens, with or without a more anterior position, is often regarded as a strong contributing factor to angle closure. Lens extraction, no matter it is cataractous or clear, can theoretically eliminate this anatomical predisposing factor of angle closure, and thus IOP can be reduced. Based on recent results of a number of clinical trials, lens extraction alone or in combination with other IOP-lowering surgeries, may therefore play a more important role in the treating primary angle closure glaucoma. In cases when greater IOP-lowering effect is needed or if drug dependency has to be minimized, combined procedures, such as phacotrabeculectomy, can be considered, but the surgical risk can be higher than lens extraction alone.

Early phacoemulsification in patients with acute primary angle closure

PURPOSE

To compare long term efficacy of phacoemulsification in the early management of acute primary angle closure (APAC) after aborting an acute attack and performing laser peripheral iridotomy (LPI).

METHODS

In this nonrandomized comparative prospective study, we included 35 subjects presenting with APAC who had responded to medical treatment and LPI with intraocular pressure (IOP) less than 25 mmHg. Twenty patients with visually significant cataract with visual acuity of <20/30 were assigned to the "Phaco/LPI" group and underwent phacoemulsification within 6 weeks of the attack. Fifteen subjects with clear lens were assigned to the "LPI Only" group and were followed clinically. The primary measured outcome was the prevalence of IOP rise after 1 month (treatment failure), defined as 1) if a patient developed IOP rise resulting in IOP >21 mmHg with or without medication, or 2) if a patient required any medication to have IOP ≤21 mmHg after 1 month. Patients were followed for at least one year.

RESULT

IOP, number of medications, gonioscopy grading, and amount of synechiae were not significantly different at baseline between the two groups. Acute attack did not recur in any patient. There was more significant failure in the LPI Only group compared with the Phaco/LPI group (40% vs. 5%; p = 0.02). There was a significant difference in final IOP between the two study groups (13.90 ± 2.17 vs. 17.8 ± 4.16 in the Phaco/LPI and LPI Only groups, respectively; p = 0.001). Patients in the Phaco-LPI group needed less medication than the other group at final follow-up. No serious complications have arisen from the immediate LPI or phacoemulsification.

CONCLUSION

Phacoemulsification is a safe procedure for preventing IOP rise after aborting acute primary angle closure if performed within a few weeks of the attack.

Lowering of Intraocular Pressure After Phacoemulsification in Primary Open-Angle and Angle-Closure Glaucoma: A Bayesian Analysis

Phacoemulsification as treatment for primary open-angle glaucoma (POAG) remains more controversial than for primary angle-closure glaucoma (PACG). If the objective of glaucoma surgery is an additional greater than or equal to 5 to 6 mm Hg reduction of intraocular pressure (IOP), the role of phacoemulsification should be based on the probability of achieving this. A Bayesian analysis of available data was performed to calculate the change in IOP after phacoemulsification in POAG and PACG. Standard meta-analysis formulation with prephacoemulsification and postphacoemulsification IOP-assumed to have normal distributions, with study-specific means and SDs-was used. Absolute and relative change in IOP was calculated using different priors, and sensitivity analyses were performed. The prior that just included a decrease of greater than or equal to 6 mm Hg in the 95% credible interval was identified. The probability of achieving greater than or equal to 5 to 6 mm Hg decrease in IOP (and other levels) was calculated. Depending on the prior, the probability of achieving a greater than or equal to 5 mm Hg reduction in IOP in POAG varied from 0.1% to 3%. Confidence in a greater than or equal to 6 mm Hg decrease required a prior belief that phacoemulsification produces a mean decrease of 7 mm Hg. The probability of a decrease in IOP was greater in PACG: approximately 50% probability of a greater than or equal to 5 mm Hg decrease in PACG uncontrolled on medications. Phacoemulsification in POAG has a high probability of producing a small decrease in IOP that may be useful in early, well-controlled disease. The probability of a clinically significant decrease of greater than or equal to 5 to 6 mm Hg-required for advanced/uncontrolled disease-is low. Results support the role of phacoemulsification in PACG.

Management of Primary Angle-Closure Glaucoma

Primary angle-closure glaucoma (PACG) is a progressive optic nerve degeneration and is defined as a glaucomatous optic neuropathy with associated characteristic enlargement of optic disc cupping and visual field loss that is secondary to ocular hypertension caused by closure of the drainage angle. Angle closure is caused by appositional approximation or adhesion between the iris and the trabecular meshwork. The main treatment strategy for PACG lies in the reduction of intraocular pressure, reopening of the closed angle, and possible prevention of further angle closure. There is no universally agreed best surgical treatment for PACG. Trabeculectomy, goniosynechialysis (GSL), glaucoma implant, and cyclodestructive procedures are effective surgical options. Each of them plays an important role in the management of PACG with its own pros and cons. Accumulating evidence is available to show the effectiveness of visually significant and visually nonsignificant cataract extraction in the treatment of PACG. Trabeculectomy and GSL are often combined with cataract extraction, which may offer additional pressure control benefits to patients with PACG. This review article will discuss laser peripheral iridotomy, argon laser peripheral iridoplasty, and surgeries such as GSL, phacoemulsification, and phaco plus glaucoma surgeries that lower intraocular pressure and also alter the anterior segment and/or drainage angle anatomy. Currently, glaucoma implants and cyclodestruction are mainly reserved for PACG patients who have failed previous filtering operations. Their role as initial surgical treatment for PACG will not be discussed.

Optical Coherence Tomography Imaging for Glaucoma - Today and Tomorrow

Digital imaging technologies for glaucoma diagnostics have evolved rapidly over the recent years. From time-domain optical coherence tomography (OCT) to spectral-domain and swept-source OCTs, the application of OCT for analysis of the anterior chamber angle and the optic nerve head (ONH) is expanding. The second-generation anterior segment swept-source OCT is able to image the configuration of the anterior chamber angle in 3 dimensions in less than 1 second and perform 360-degree analysis of the anterior chamber angle width for detection of angle closure. The morphology, density, and dimensions of the crystalline lens in relation to the anterior chamber can now be examined from the anterior corneal surface to the posterior lens surface, facilitating the investigation of the involvement of the crystalline lens in primary angle closure. Spectral-domain and swept-source OCTs have improved the measurement reliability of the lamina cribrosa and the neuroretinal rim configurations. Studying the deformation of the lamina cribrosa and ONH surfaces is relevant to decipher the mechanisms of ONH damage in the development and progression of glaucoma. Software and algorithms for automatic analysis of the anterior chamber angle dimensions and deformation of the ONH and lamina cribrosa surfaces are required to process large volumetric data sets, and they are under active development. It is expected that new imaging technologies will improve the detection and risk assessment of angle-closure and open-angle glaucomas.

Effect of Goniosynechialysis During Phacoemulsification on IOP in Patients With Medically Well-controlled Chronic Angle-Closure Glaucoma

PURPOSE

To evaluate and compare the efficacy and safety of combined phacoemulsification and goniosynechialysis (PEGS) to phacoemulsification alone (PE) in patients with medically well-controlled chronic angle-closure glaucoma (CACG) with cataracts.

MATERIALS

Thirty eyes diagnosed with CACG and requiring cataract surgery from January 2008 to October 2010 were prospectively randomized, 15 each to PE and PEGS. Changes in peripheral anterior synechiae (PAS), intraocular pressure (IOP), anterior chamber depth, and number of antiglaucoma drugs from baseline to 2 months after the operation were analyzed, as were the type and number of complications.

RESULTS

The PE group showed decreases in PAS (118.67±95.38 degrees) and IOP (2.33±2.38 mm Hg) and a significant reduction in the number of antiglaucoma drugs (0.53±0.83, P<0.05) from before to 2 months after surgery. The PEGS group showed similar decreases in PAS (114.00±90.95 degrees), and IOP (4.53±4.16 mm Hg) and number of antiglaucoma drugs (1.20±1.32) (P<0.05). However, the amount of decline in both the groups did not show any significantly difference in PAS, reduction of IOP, or number of antiglaucoma drugs (P>0.05), The increase in anterior chamber depth from baseline to 2 months after surgery was significantly greater in the PEGS group (P=0.003).

CONCLUSIONS

The IOP-lowering effects of PEGS do not differ significantly from those of PE in medically well-controlled CACG patients with cataract. These results suggest that additional goniosynechialysis during phacoemulsification is not necessary in such patients.

Combined surgery versus cataract surgery alone for eyes with cataract and glaucoma

BACKGROUND

Cataract and glaucoma are leading causes of blindness worldwide, and their co-existence is common in elderly people. Glaucoma surgery can accelerate cataract progression, and performing both surgeries may increase the rate of postoperative complications and compromise the success of either surgery. However, cataract surgery may independently lower intraocular pressure (IOP), which may allow for greater IOP control among patients with co-existing cataract and glaucoma. The decision between undergoing combined glaucoma and cataract surgery versus cataract surgery alone is complex. Therefore, it is important to compare the effectiveness of these two interventions to aid clinicians and patients in choosing the better treatment approach.

OBJECTIVES

To assess the relative effectiveness and safety of combined surgery versus cataract surgery (phacoemulsification) alone for co-existing cataract and glaucoma. The secondary objectives include cost analyses for different surgical techniques for co-existing cataract and glaucoma.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 10), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to October 2014), EMBASE (January 1980 to October 2014), PubMed (January 1948 to October 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to October 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 3 October 2014.We checked the reference lists of the included trials to identify further relevant trials. We used the Science Citation Index to search for references to publications that cited the studies included in the review. We also contacted investigators and experts in the field to identify additional trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of participants who had open-angle, pseudoexfoliative, or pigmentary glaucoma and age-related cataract. The comparison of interest was combined cataract surgery (phacoemulsification) and any type of glaucoma surgery versus cataract surgery (phacoemulsification) alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, collected data, and judged risk of bias for included studies. We used standard methodological procedures expected by the Cochrane Collaboration.

MAIN RESULTS

We included nine RCTs, with a total of 655 participants (657 eyes), and follow-up periods ranging from 12 to 30 months. Seven trials were conducted in Europe, one in Canada and South Africa, and one in the United States. We graded the overall quality of the evidence as low due to observed inconsistency in study results, imprecision in effect estimates, and risks of bias in the included studies.Glaucoma surgery type varied among the studies: three studies used trabeculectomy, three studies used iStent® implants, one study used trabeculotomy, and two studies used trabecular aspiration. All of these studies found a statistically significant greater decrease in mean IOP postoperatively in the combined surgery group compared with cataract surgery alone; the mean difference (MD) was -1.62 mmHg (95% confidence interval (CI) -2.61 to -0.64; 489 eyes) among six studies with data at one year follow-up. No study reported the proportion of participants with a reduction in the number of medications used after surgery, but two studies found the mean number of medications used postoperatively at one year was about one less in the combined surgery group than the cataract surgery alone group (MD -0.69, 95% CI -1.28 to -0.10; 301 eyes). Five studies showed that participants in the combined surgery group were about 50% less likely compared with the cataract surgery alone group to use one or more IOP-lowering medications one year postoperatively (risk ratio (RR) 0.47, 95% CI 0.28 to 0.80; 453 eyes). None of the studies reported the mean change in visual acuity or visual fields. However, six studies reported no significant differences in visual acuity and two studies reported no significant differences in visual fields between the two intervention groups postoperatively (data not analyzable). The effect of combined surgery versus cataract surgery alone on the need for reoperation to control IOP at one year was uncertain (RR 1.13, 95% CI 0.15 to 8.25; 382 eyes). Also uncertain was whether eyes in the combined surgery group required more interventions for surgical complications than those in the cataract surgery alone group (RR 1.06, 95% CI 0.34 to 3.35; 382 eyes). No study reported any vision-related quality of life data or cost outcome. Complications were reported at 12 months (two studies), 12 to 18 months (one study), and two years (four studies) after surgery. Due to the small number of events reported across studies and treatment groups, the difference between groups was uncertain for all reported adverse events.

AUTHORS' CONCLUSIONS

There is low quality evidence that combined cataract and glaucoma surgery may result in better IOP control at one year compared with cataract surgery alone. The evidence was uncertain in terms of complications from the surgeries. Furthermore, this Cochrane review has highlighted the lack of data regarding important measures of the patient experience, such as visual field tests, quality of life measurements, and economic outcomes after surgery, and long-term outcomes (five years or more). Additional high-quality RCTs measuring clinically meaningful and patient-important outcomes are required to provide evidence to support treatment recommendations.

The Impact of Lens Vault on Visual Acuity and Refractive Error: Implications for Management of Primary Angle-closure Glaucoma

PURPOSE

To investigate the relationship between lens vault (LV), visual acuity (VA), and refraction.

METHODS

This was a cross-sectional study of 2047 subjects aged 50 years and older recruited from a community polyclinic. Anterior segment optical coherence tomography was performed, and customized software was used to measure LV. VA was measured using a logarithm of minimum angle of resolution chart (logMAR chart; Lighthouse Inc.), and was classified as normal (logMAR<0.3), mild impairment (0.3<logMAR<0.6), and moderate/severe impairment (logMAR>0.6). Refraction was measured with an autorefractor machine and spherical equivalent was defined as sphere plus half cylinder. Angle closure was defined as posterior trabecular meshwork not visible for ≥2 quadrants on nonindentation gonioscopy.

RESULTS

Complete data were available for 1372 subjects including 295 (21.5%) with angle closure. Angle-closure subjects were significantly older (P<0.001), with shorter axial length (P<0.001), shallower anterior chamber depth (P<0.001), and greater LV (P<0.001). There was no significant difference in VA (P=0.12) compared with those without angle closure. After adjusting for age, sex, axial length, anterior chamber depth, and spherical equivalent, there was no significant association between LV and VA (P=0.35) or between LV and spherical equivalent (P=0.06).

CONCLUSIONS

The magnitude of LV was not associated with VA or spherical equivalent. Lens extraction may be a consideration in eyes with angle closure with large LV in the absence of visually significant cataract.

Complications and outcomes of primary phacotrabeculectomy with mitomycin C in a multi-ethnic asian population

PURPOSE

To determine the occurrence of intraoperative and postoperative complications up to three years after primary phacotrabeculectomy with intraoperative use of Mitomycin C (MMC) in primary open angle (POAG) and primary angle closure glaucoma (PACG) patients, and the effect of postoperative complications on surgical outcome.

METHODS

Retrospective review of 160 consecutive patients with POAG (n = 105) and PACG (n = 55), who underwent primary phacotrabeculectomy with MMC at the National University Hospital, Singapore, from January 1, 2008 to December 31, 2010. Data was collected using a standardized form that included patient demographic information, ocular characteristics and postoperative complications, including hypotony (defined as intraocular pressure < 6 mmHg), shallow anterior chamber (AC) and hyphema.

RESULTS

The mean age ± standard deviation (SD) of patients was 68.2 ± 8.2 years. No patient lost light perception during duration of follow-up. 77% of the postoperative complications occurred within the first month only. The commonest complications were hypotony (n = 41, 25.6%), hyphema (n = 16, 10.0%) and shallow AC (n = 16, 10.0%). Five patients (3.1%) required reoperation for their complications. Early hypotony (defined as hypotony < 30 days postoperatively) was an independent risk factor for surgical failure (hazard ratio [HR], 5.1; 95% CI, 1.6-16.2; p = 0.01). Hypotony with another complication was also a risk factor for surgical failure (p < 0.02).

CONCLUSIONS

Hypotony, hyphema and shallow AC were the commonest postoperative complications in POAG and PACG patients after phacotrabeculectomy with MMC. Most complications were transient and self-limiting. Early hypotony within the first month was a significant risk factor for surgical failure.

Cataract surgery and intraocular pressure

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

Guidelines for treatment of chronic primary angle-closure glaucoma

OBJECTIVE

To present a clinical practice guideline update on the medical, laser, and surgical treatment of primary angle closure glaucoma (PACG) in adults.

METHODS

Following the formulation of key questions using the PICO scheme (Patient/Problem, Intervention, Comparison, Outcome), a systematic review was performed on the literature published to date, including international clinical practice guidelines. The AMSTAR and Risk of Bias tools were used for evaluating the quality of the information. The level of evidence and grade of recommendation was established following the Scottish Intercollegiate Guidelines Network (SIGN) system.

RESULTS

Following the above methodology, recommendations of medical, laser and surgical treatment in adult PACG and levels of evidence are presented.

CONCLUSIONS

Although the level of scientific evidence for many of the questions raised is not very high, a review is presented on updated treatment recommendations for adult PACG. Among the limitations for the implementation of these recommendations is that most studies have been conducted in Asian populations, and that the effectiveness is measured almost exclusively in terms of reducing intraocular pressure, and does not include visual function, quality of life or cost-effectiveness parameters.

Factors correlating with failure to control intraocular pressure in primary angle-closure glaucoma eyes with coexisting cataract treated by phacoemulsification or combined phacotrabeculectomy

PURPOSE

To identify clinical factors correlating with failure to control intraocular pressure (IOP) in primary angle-closure glaucoma (PACG) eyes with cataract after phacoemulsification or phacotrabeculectomy.

DESIGN

Retrospective analysis of two prospective randomized controlled clinical trials.

METHODS

Primary angle-closure glaucoma eyes with cataract received phacoemulsification or phacotrabeculectomy. Failure was defined as having IOP of 21mm Hg or greater, or requiring glaucoma drugs to maintain an IOP of less than 21 mm Hg, or having had additional IOP-lowering surgery. Factors correlating with failure at 24 months after surgery were identified using logistic regression model.

RESULTS

One hundred twenty-three PACG eyes with cataract and receiving phacoemulsification (n = 62) and phacotrabeculectomy (n = 61) were analyzed. With univariate analysis, factors associated with failure included a higher preoperative IOP, a higher preoperative requirement for glaucoma drugs, absence of plateau iris configuration, and phacoemulsification alone. With multivariate analysis, factors associated with failure included a higher preoperative IOP [odds ratio (OR), 1.732 per increase in IOP of 5 mm Hg], a higher preoperative requirement for glaucoma drugs (OR, 1.913), and performance of phacoemulsification alone (OR, 10.24).

CONCLUSIONS

In PACG eyes with cataract, higher preoperative IOP and increased requirement for glaucoma drugs correlate with failure to control IOP after phacoemulsification or phacotrabeculectomy. Phacotrabeculectomy is more likely than phacoemulsification to achieve IOP control.

The effect of cataract extraction on intraocular pressure

PURPOSE OF REVIEW

To examine the current literature covering the long-term effect of cataract extraction on intraocular pressure (IOP).

RECENT FINDINGS

As a result of the high rate of cataract surgery, the impact on IOP continues to be the subject of multiple studies in different populations. Recent publications include those that distinguish patients with open angles from those with more narrow angles, as well as prospective analyses that address the impact of regression to the mean and other types of bias on the effect of postoperative IOP lowering.

SUMMARY

There are sufficient data to suggest that cataract surgery provides a lowering effect on IOP in the long term. This effect appears to be proportional to preoperative IOP. Eyes with higher preoperative IOP have the greatest average lowering, whereas eyes with IOP in the lower range of statistically normal tend to have an IOP that is unchanged from baseline or even higher following cataract surgery. In patients with narrow angles, the IOP-lowering effect appears to also be proportional to the degree of anterior chamber deepening induced by cataract surgery.

The effect of phacoemulsification on intraocular pressure in medically controlled open-angle glaucoma patients

PURPOSE

To evaluate intraocular pressure (IOP) after phacoemulsification in patients with medically controlled open-angle glaucoma (OAG), and examine the association of biometric variables to IOP changes.

DESIGN

Retrospective case series.

METHODS

Open-angle glaucoma patients without prior incisional glaucoma surgery undergoing phacoemulsification by a single surgeon between January 1997 and October 2011 were evaluated. Patient charts were reviewed to obtain demographic information, preoperative glaucoma medications, severity and treatment measures, and preoperative and postoperative IOP.

RESULTS

A total of 157 eyes (157 patients) were included in the study. The average preoperative IOP of 16.3 ± 3.6 mm Hg decreased to 14.5 ± 3.4 mm Hg at 1 year (P < .001). Sixty eyes (38%) required additional medications or laser for IOP control within the first year postoperatively, or had a higher IOP at postoperative year 1 without medication change. Among eyes without postoperative medication changes (n = 102), higher preoperative IOP (P < .001), older age (P = .006), and deeper anterior chamber depth (P = .015) were associated with lower postoperative IOP.

CONCLUSIONS

Phacoemulsification resulted in a small average decrease in IOP in patients with OAG. A sizeable proportion of medically controlled glaucoma patients with open angles undergoing phacoemulsification experienced an increase in IOP or required more aggressive treatment to control IOP postoperatively.

Effects of phacoemulsification on intraocular pressure and anterior chamber depth

The aim of this study was to investigate the effects of phacoemulsification with intraocular lens (IOL) implantation on intraocular pressure (IOP) and anterior chamber depth (ACD) in patients with cataract or cataract associated with primary angle closure (PAC). A total of 361 patients (481 affected eyes) with senile cataract (cataract group) and 44 patients (52 affected eyes) with cataract associated with PAC (cataract with PAC group) underwent phacoemulsification with IOL implantation from July 2005 to May 2007 and were followed up for 3 to 25 months. There was a significant difference between pre-operative and post-operative IOPs (t=9.270, P<0.01) in the cataract group and in the cataract with PAC group (t=3.29, P<0.01). No significant differences were identified in pre-operative IOP (t=-2.437, P>0.05) and the IOP three months after surgery (t=2.154, P>0.05) between the two groups. There was a significant difference between the pre-operative and post-operative ACDs (t=7.781, P<0.01) in the cataract group and in the cataract with PAC group (t=4.528, P<0.01). A significant difference in ACD between the two groups (t=8.325, P<0.01) existed prior to surgery but following surgery, the ACDs of the two groups were not significantly different (t=2.86, P>0.05). Phacoemulsification with IOL implantation has IOP-lowering effects on cataract and cataract with PAC patients. The International Society of Geography and Epidemiology of Ophthalmology classification method for angle closure glaucoma was adopted in our study. Furhter studies are required to prove the safety and mechanism of lowering IOP impact of phacoemulsifation towards PAC glaucoma (PACG).

Management algorithms for primary angle closure disease

In contrast to primary open angle glaucoma, preventive interventions in primary angle closure disease (PACD) can sometimes be definitive. Data from randomized, controlled trials - and where this is not available - principles grounded in known biology, biological plausibility, logic, preferred practice and personal experience have been synthesized to develop explicit clinical algorithms for management of the spectrum of PACD. The mainstay of first-line intervention is usually a laser iridotomy: a commonly necessary but sometimes insufficient manoeuvre in PACD. The crucial stepwise considerations after iridotomy are: whether the angle is open or closed; whether the IOP can be medically controlled; the extent of PAS, and the presence of visually significant cataract. Indication for subsequent interventions--which may include iridoplasty, cataract surgery, trabeculectomy or phacotrabeulectomy--are herein based on an arbitrary threshold (180 degrees) for angle opening and extent of PAS following initial treatment.

Phacoemulsification versus trabeculectomy in medically uncontrolled chronic angle-closure glaucoma without cataract

OBJECTIVE

To compare phacoemulsification versus trabeculectomy with adjunctive mitomycin C in medically uncontrolled chronic angle-closure glaucoma (CACG) without cataract.

DESIGN

Prospective, randomized clinical trial.

PARTICIPANTS

Fifty medically uncontrolled CACG eyes without cataract of 50 patients.

INTERVENTION

Patients were randomized into undergoing either phacoemulsification or trabeculectomy with adjunctive mitomycin C. After surgery, patients were followed up every 3 months for 2 years.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP) and requirement for glaucoma drugs.

RESULTS

Twenty-six CACG eyes were randomized to receive phacoemulsification, and 24 eyes underwent trabeculectomy with mitomycin C. Phacoemulsification and trabeculectomy resulted in significant and comparable IOP reduction at 24 months after surgery (reduction of 8.4 mmHg or 34% for phacoemulsification vs. 8.9 mmHg or 36% for trabeculectomy; P=0.76). Over first 24 months, trabeculectomy-treated eyes required on average 1.1 fewer drugs than phacoemulsification-treated eyes (P<0.001). However, trabeculectomy was associated with significantly more surgical complications than phacoemulsification (46% vs. 4%; P=0.001). Eight (33%) of 24 trabeculectomy eyes demonstrated cataract during follow-up.

CONCLUSIONS

Both phacoemulsification and trabeculectomy are effective in reducing IOP in medically uncontrolled CACG eyes without cataract. Trabeculectomy is more effective than phacoemulsification in reducing dependence on glaucoma drugs, but is associated with more complications.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Effects of combined phacoemulsification and viscogoniosynechialysis versus trabeculectomy in patients with primary angle-closure glaucoma and coexisting cataract

AIMS

To compare the effectiveness of combined phacoemulsification and viscogoniosynechialysis versus trabeculectomy alone in primary angle-closure glaucoma (PACG) with a coexisting cataract.

METHODS

Thirty-nine Chinese patients (39 eyes) were retrospectively analyzed: 19 patients underwent combined phacoemulsification and viscogoniosynechialysis (group 1), and 20 underwent trabeculectomy (group 2). In both groups, the intraocular pressure (IOP), the number of antiglaucoma medications, the best corrected visual acuity (BCVA), the central anterior chamber depth (ACD), the synechial/apposition angle closure (SAC), and the success rates were assessed.

RESULTS

The median follow-up periods were similar for both groups (10 months). At the last follow-up, the mean IOP was 14.09 ± 6.89 mm Hg and the mean number of antiglaucoma medications was 0.36 ± 0.59 in group 1; in group 2, the mean IOP was 16.48 ± 4.74 mm Hg (p = 0.066) and the mean number of antiglaucoma medications was 1.05 ± 0.99 (p = 0.025). In terms of the mean central ACD and the mean SAC, there were significant differences between the groups (p = 0.0000, respectively). Kaplan-Meier analysis revealed that the cumulative probability of success in group 1 was higher than that in group 2 (p = 0.0051).

CONCLUSION

Compared to trabeculectomy, combined phacoemulsification and viscogoniosynechialysis resulted in a lower requirement for glaucomatous medications, a greater improvement in BCVA, and a higher cumulative probability that treatment would be successful among patients with PACG and coexisting cataracts.

Malignant glaucoma: a review of the modern literature

Malignant glaucoma is a rare form of glaucoma that typically follows surgery in patients with primary angle closure and primary angle-closure glaucoma. In this paper, the clinical features, classification, pathogenesis, and principles of management are discussed. Despite a high prevalence of primary angle closure glaucoma in South-East Asia, the vast majority of cases of malignant glaucoma are reported in White populations. This may reflect differing mechanisms of angle closure in White and Asian patients, which somehow reduces the likelihood of an aberrant relationship developing between the lens, ciliary body, anterior hyaloid, and vitreous structures within the eye. Although the exact underlying pathogenic mechanism remains unclear, the prognosis is good with modern medical, laser, and surgical treatment modalities.