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

Ocular Characteristics of Pseudophakic Eyes with Malignant Glaucoma

INTRODUCTION

The aim of the study was to investigate the clinical characteristics and treatment outcomes of the pseudophakic eyes with malignant glaucoma (MG).

METHODS

This retrospective case-control study enrolled 53 eyes of 47 patients with primary angle-closure glaucoma having cataract surgery history, including 19 patients (25 eyes) diagnosed with MG and 28 patients (28 eyes) without MG as the match. Among patients diagnosed with MG, 14 patients (18 eyes) underwent zonulo-hyaloido-vitrectomy (ZHV) and the other 5 patients (7 eyes) received conservative treatments. The visual acuity, refraction status, intraocular pressure (IOP), extent of peripheral anterior synechia, classes of anti-glaucoma medications, and ultrasound biomicroscopy (UBM) examination were recorded before cataract surgery, at the diagnosis of MG, and 3 months after ZHV or atropine application, respectively.

RESULTS

In the pseudophakic eyes with MG, the IOP cannot be well controlled compared to the matched eyes (27.24 ± 8.72 mm Hg vs. 14.30 ± 2.63 mm Hg, p < 0.001). In addition, there was a difference in the average spherical equivalent refractive error between 2 groups of patients (-2.23 ± 0.84 D in MG vs. -0.12 ± 0.64 D in the matched eyes, p < 0.001). By UBM analysis, the anterior chamber depth (ACD) was shallower in MG than that in the matched eyes (2.34 ± 0.20 mm vs. 3.47 ± 0.29 mm, p < 0.001). The difference between the anterior vault distance of the pseudophakic eyes with MG and that of the matched eyes was also significant (p < 0.001). After treated with ZHV, the IOP was greatly decreased from 27.84 ± 10.14 mm Hg to 15.85 ± 4.41 mm Hg (p < 0.001). The refractive error also changed from -2.11 ± 0.91 D to +0.42 ± 0.99 D (p < 0.001). At the same time, the central ACD was significantly deepened from 2.30 ± 0.39 mm to 3.30 ± 0.31 mm (p < 0.001).

CONCLUSION

Uncontrolled IOP and shallow anterior chamber both centrally and peripherally are the primary clinical characteristics for the pseudophakic eyes with MG. An unexpected refractive error or myopic shift for the eyes with PACG after cataract surgery can be an important hint for diagnosis of MG. The typical UBM image is an anterior displacement of the lens-iris diaphragm and a bow-shaped change of the intraocular lens. It is an effective way to treat pseudophakic MG with the ZHV through a peripheral iridectomy.

Safety and Efficacy of the Preserflo® Microshunt in Refractory Glaucoma: A One-Year Study

Purpose: To evaluate the safety and efficacy of Preserflo^® microshunt implantation in eyes with refractory glaucoma. Methods: In this retrospective study, a cohort of patients who underwent Preserflo^® microshunt implantation between April 2019 and August 2020 for refractory glaucoma were evaluated. At the time of surgery, all eyes had uncontrolled intraocular pressure (IOP) despite maximally tolerated medical therapy and at least one previous failed glaucoma filtering surgery. The primary outcome was a complete success, defined as postoperative IOP ≤ 21 mm Hg with an IOP reduction ≥ 20% and no repeat filtering surgery. The secondary outcome was qualified success, defined as a complete success with the use of antiglaucoma medications. The rates of needling, bleb repair, and postoperative complications were also recorded. Results: Forty-seven eyes with a mean preoperative IOP of 30.1 ± 7.1 mm Hg and a mean of 3.4 ± 1 glaucoma medications were included. The mean number of previous surgeries prior to microshunt implantation was 2.3 ± 1.3. After 1 year, the mean IOP was significantly reduced to 18.8 ± 4.6 mm Hg, with the mean number of medications significantly reduced to 1.4 ± 1.2. Complete success was achieved in 35% of eyes, and a qualified success in 60% of eyes. A decrease in IOP of at least 30% was found in 55% of eyes. Needling or bleb repair was performed in 49% of eyes. Complications were minimal and transient, except for one eye which presented with tube extrusion, and another eye with a transected tube. A repeat glaucoma surgery had to be performed in 17% of eyes. Conclusions: The Preserflo^® Microshunt provided moderate success but a significant reduction in IOP, with a good safety profile after one year of follow-up in eyes at high risk for failure of filtering surgery.

Safety and efficacy of incisional goniotomy as an adjunct with phacoemulsification in primary angle-closure glaucoma

PURPOSE

To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of incisional goniotomy as an adjunct to phacoemulsification in primary angle-closure glaucoma (PACG) patients.

METHODS

Consecutive patients with PACG (high or borderline IOP) deemed fit for phacoemulsification were enrolled. After phacoemulsification, incisional goniotomy was performed with or without goniosynechialysis. Patient demographic profile, clinical data, and adverse events, if any, were analyzed during at least a 6-month follow-up period. Success was defined as IOP of 18 mm Hg or lesser with or without medications.

SETTING

Tertiary care Ophthalmic hospital.

DESIGN

Prospective interventional case series.

RESULTS

Of 46 eyes (38 patients) included, 69.6% eyes were classified as having advanced glaucoma. The mean treated IOP decreased by 7.3 ± 1.0 (SE) mm Hg (95% CI, 5.2-9.3) from 21.4 ± 6.6 to 14.2 ± 3.7 mm Hg at a mean duration of 11.7 ± 5.5 months (6-22 months) postoperatively (P < .001, paired t test). There was 66.6% reduction in median number of hypotensive medications (P < .001, Wilcoxon signed-rank test). Observed complications included hyphema (13 eyes [28%]), IOP spike (3 eyes [6.5%]), and cyclodialysis (1 eye [2.17%]). High treated IOP and number of medications were significantly associated with failure in univariate analysis (P < .05, Fisher exact test). The cumulative survival probability for qualified success at 22 months was 87.8% ± 0.07 (95% CI, 0.65-0.96).

CONCLUSIONS

Incisional goniotomy as an adjunct with phacoemulsification resulted in a significant and sustained reduction in IOP along with decrease in number of glaucoma medications in chronic PACG eyes, irrespective of the disease stage.

The role of lens extraction in glaucoma management

Cataract extraction has become a much safer procedure with the development of phacoemulsification, extending its application in ocular conditions such as glaucoma for better disease control. This review aims at summarizing the effect of lens extraction with or without combined glaucoma surgeries in different types of glaucoma and describing the intraoperative techniques and changes of glaucoma care postoperatively. A comprehensive literature search was performed through Medline and PubMed, and 67 studies were selected for this review. In primary angle closure (PAC) diseases, studies have revealed significant intraocular pressure (IOP) and medication requirement reduction after lens extraction. Fewer studies described its application in primary open angle glaucoma (POAG) and ocular hypertension (OHT), but literature available suggests that it can also lead to better disease control. Likewise, lower postoperative IOP and pressure fluctuations have been shown in normal tension glaucoma (NTG). Advanced glaucoma, shallow anterior chamber and pseudoexfoliation glaucoma (PXG) are three difficult scenarios that are commonly encountered in cataract operations. Special techniques in preventing complications such as wipe out phenomenon are depicted. Goniosynechialysis, endoscopic cyclophotocoagulation and trabecular microbypass stents are a few of the popular choices of glaucoma procedures that can be performed concomitantly with phacoemulsification but evidence of their efficacy needs to be further verified. Cataract operation can improve visual field and retinal nerve fiber layer examination parameters and it is advised to set new baselines after the surgery for subsequent progression monitoring. Clearance of an optically significant cataract results in better quality of life, and with detailed and thorough explanation of the indications, expectations and risks of the surgery, cataract extraction could be considered even in cases of advanced glaucoma.

Has the EAGLE landed for the use of clear lens extraction in angle-closure glaucoma? And how should primary angle-closure suspects be treated?

Angle-closure glaucoma is an aggressive condition that causes millions to become blind worldwide. This review explores the use of prophylactic laser peripheral iridotomy (PI) in patients classified as primary angle-closure suspects (PACS), and additionally, the use of clear lens exchange as a primary treatment option in established angle-closure disease with or without glaucoma. As PI has a strong prophylactic effect in fellow eyes of patients who have had an acute attack, its use has been widely adopted in those patients classified as PACS, but with limited evidence to support this. A large randomised trial conducted in China has demonstrated that although PI reduces the risk of incident angle-closure disease, the incidence of disease that would threaten vision was much lower than anticipated. This suggests that the benefit of prophylactic PI is very limited. Health services data shows an association between rising cataract surgical rates and of decreasing rates of acute angle-closure. Age-related growth of the lens is a major component of angle-closure disease. Several studies have shown that clear lens extraction (CLE) effectively lowers IOP in angle-closure. The use of CLE as a primary treatment option has been tested against LPI in the EAGLE study, a large RCT that enroled people with angle-closure and an IOP > 30 mmHg, and those with angle-closure glaucoma. The trial showed CLE to be superior to PI both for IOP control and patient reported quality of life. On these grounds, CLE should be considered for first-line treatment of more advanced angle-closure disease.

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.