Extracapsular cataract extraction with posterior chamber lens implantation in primary angle-closure glaucoma

Chronic angle-closure with glaucomatous damage: long-term clinical course in a North American population and comparison with an Asian population

PURPOSE

To study the long-term clinical course of North American chronic angle-closure glaucoma (CACG) patients with optic disc damage and visual field loss in the presence of an angle closed at least partially by peripheral anterior synechiae and to compare it with a similar group of Singaporean patients.

DESIGN

A retrospective, interventional case-control study series.

PARTICIPANTS

Fifty-one patients (80 eyes) diagnosed with CACG with glaucomatous optic nerve head and visual field damage at a New York hospital from January 1990 through December 1994. All study eyes underwent laser peripheral iridotomy (LPI).

METHODS

The presenting features, management, and subsequent long-term intraocular pressure (IOP) outcome were analyzed and compared with 65 Asian patients (83 eyes) from a Singapore hospital who were similarly diagnosed during the same period.

MAIN OUTCOME MEASURES

The long-term outcome after LPI was assessed in terms of IOP and the requirement for additional therapy.

RESULTS

The mean presenting IOP was higher in the Singapore eyes (40 +/- 15 mmHg) compared with the New York eyes (31 +/- 12.5 mmHg). All 80 New York eyes (100%) and 78 of 83 Singapore eyes (94%) required further treatment to control IOP during follow-up. Of the eyes with a subsequent rise in IOP, 33 of 80 eyes (41.3%) compared with 34 of 83 eyes (41.0%) of the Singapore patients were controlled with additional topical medication. Of the New York eyes, 25 of 80 (31.3%) eventually underwent filtering surgery, compared with 44 of 83 (53.0%) in the Singapore study. The other 22 eyes (27.5%) in the New York group went on to additional laser procedures, peripheral iridoplasty, laser trabeculoplasty, or a combination thereof, after which IOPs were controlled and no surgery was required. There was no similar comparison for the Singapore group, because these eyes went directly on to surgery.

CONCLUSIONS

Despite the presence of a patent LPI, most eyes with CACG presenting with elevated IOP and having both optic disc and visual field damage in both populations required further treatment to control IOP. Results in the American population are similar to that reported in Asian patients.

Review of recent advancements in the understanding of primary angle-closure glaucoma

Primary angle-closure glaucoma is a leading cause of blindness worldwide. However, the terminology used for angle-closure in the literature is inconsistent, with inappropriate emphasis on symptomatology. A new nomenclature for primary angle-closure glaucoma focuses on the presence of end-organ damage and limits the use of the term "glaucoma" only for people who have suffered injury to the optic nerve. This review describes the various modalities of treatment for primary angle-closure glaucoma. The role and limitations of laser peripheral iridotomy in the management of the different forms of the disease are summarized. Recent developments have led to improvements in the understanding of the epidemiology, clinical course, and treatment of the condition.

Glaucoma in China: how big is the problem?

AIMS

To derive preliminary estimates for the number of adults in China suffering from glaucoma, and project the burden of visual morbidity attributable to primary and secondary glaucoma.

METHODS

Age and sex specific data from two population surveys were applied to US Census Bureau population estimates for urban and rural China. It was assumed that data from Singapore were representative of urban China, and those from Mongolia were representative of rural China.

RESULTS

It was estimated that 9.4 million people aged 40 years and older in China have glaucomatous optic neuropathy. Of this number, 5.2 million (55%) are blind in at least one eye and 1.7 million (18.1%) are blind in both eyes. Primary angle closure glaucoma (PACG) is responsible for the vast majority (91%) of bilateral glaucoma blindness in China. The number of people with the anatomical trait predisposing to PACG (an "occludable" drainage angle) is in the region of 28.2 million, and of these 9.1 million have significant angle closure, indicated by peripheral anterior synechiae or raised intraocular pressure.

CONCLUSIONS

This extrapolation of data from two east Asian countries gives an approximate number of people in China suffering from glaucoma. It is unlikely that this crude statistical model is entirely accurate. However, the authors believe the visual morbidity from glaucoma in China is considerable. PACG is probably the leading cause of glaucoma blindness in both eyes, and warrants detailed investigation of strategies for prevention.

Effect of cataract surgery on intraocular pressure control in glaucoma patients

PURPOSE

To examine the effect of cataract surgery on intraocular pressure (IOP) control in eyes with angle-closure glaucoma (ACG) and open-angle glaucoma (OAG).

SETTING

Hayashi Eye Hospital, Fukuoka, Japan.

METHODS

This study included 74 eyes with ACG and 68 eyes with OAG having cataract surgery. The IOP was measured and the number of glaucoma medications recorded preoperatively, 1 month postoperatively, and then every 3 months. The IOP control in the 2 groups was compared using survival analysis, with failure criteria being an IOP greater than 21 mm Hg, addition of medications, or the need for additional glaucoma surgery.

RESULTS

The mean IOP and number of medications decreased significantly after surgery in both groups (P <.0001). However, the mean decrease in IOP and percentage of IOP reduction in the ACG group were greater than in the OAG group, and fewer medications were required in the ACG group. The cumulative survival probability of IOP control at 24 months was 91.9% in the ACG group and 72.1% in the OAG group. The survival curve in the ACG group was significantly better than in the OAG group (P =.0012). The IOP was controlled without medication in 30 eyes (40.5%) in the ACG group and 13 (19.1%) in the OAG group; the difference between groups was significant (P =.0055).

CONCLUSIONS

Cataract surgery substantially reduced IOP and the number of medications required for IOP control in glaucomatous eyes. Specifically, cataract extraction normalized the IOP in most eyes with ACG.

The efficacy and safety of combined phacoemulsification, intraocular lens implantation, and limited goniosynechialysis, followed by diode laser peripheral iridoplasty, in the treatment of cataract and chronic angle-closure glaucoma

PURPOSE

To report the efficacy and safety of combined phacoemulsification, intraocular lens implantation, and limited goniosynechialysis, followed by diode laser peripheral iridoplasty, in the treatment of cataract and chronic angle-closure glaucoma.

METHODS

Patients with chronic angle-closure glaucoma with total synechial angle closure and intraocular pressures higher than 21 mm Hg on maximally tolerated medications, and concurrent cataract, underwent phacoemulsification with posterior chamber intraocular lens implantation and goniosynechialysis followed by diode laser peripheral iridoplasty to the inferior half of the angle. Intraoperative complications, postoperative visual acuity, intraocular pressures, and complications were evaluated.

RESULTS

Seven eyes of seven patients received the operation, and the mean follow-up was 8.9 months (range, 2-16 months). The mean preoperative intraocular pressure was 33.0 +/- 4.8 mm Hg. The mean postoperative intraocular pressure at most recent follow-up was 13.3 +/- 2.9 mm Hg. The absolute success rate (intraocular pressure less than 21 mm Hg without medication) was 100%. The visual acuity of all eyes improved by more than two Snellen lines. Postoperative complications included intraocular pressure spike, hyphema, and transient corneal decompensation.

CONCLUSION

It appears that phacoemulsification with intraocular lens implantation combined with inferior 180 degree goniosynechialysis followed by diode laser peripheral iridoplasty is an effective and safe surgical procedure for treating chronic angle-closure glaucoma with total synechial angle closure and cataract.

Long-term clinical course of primary angle-closure glaucoma in an Asian population

PURPOSE

To study the long-term clinical course of patients with primary angle-closure glaucoma (PACG).

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Sixty-five consecutive patients who were diagnosed with PACG at one Singapore hospital from January 1990 through December 1994.

METHODS

Primary angle-closure glaucoma was defined as the presence of glaucomatous optic neuropathy and compatible visual field loss associated with a closed angle in the same eye. All study eyes underwent laser peripheral iridotomy (LPI). There were two groups of patients studied. Group A consisted of those with a past documented history of an episode of acute angle closure (that had resolved after LPI). Group B consisted of those with no previous acute episode. The presenting features, management, and subsequent long-term intraocular pressure (IOP) outcome were analyzed.

MAIN OUTCOME MEASURES

Intraocular pressure and the need for further glaucoma treatment.

RESULTS

The follow-up period was 63 +/- 29 months (mean +/- standard deviation). The mean presenting IOP was 40 +/- 16 mmHg, and the presenting vertical cup-to-disc ratio was 0.6 +/- 0.2. Of the 83 eyes, only five eyes (6%) did not require any treatment after LPI in the long term. In group A (35 eyes), all eyes required further treatment with antiglaucoma medications. Twenty-two eyes (62. 9%) eventually underwent filtering surgery at a mean of 7.3 months after the commencement of treatment. In group B (48 eyes), 43 eyes (89.6%) underwent further medical therapy, of which 22 eyes (45.8%) eventually underwent filtering surgery at a mean of 18.4 months after the commencement of treatment.

CONCLUSIONS

Despite the presence of a patent LPI, most eyes with established PACG require further treatment to control IOP. Medical therapy fails in most cases, necessitating filtering surgery. Patients risk experiencing further glaucomatous visual damage if this trend is not detected.

Changes in anterior chamber angle width and depth after intraocular lens implantation in eyes with glaucoma

OBJECTIVE

To examine the changes in anterior chamber angle width and depth induced by intraocular lens (IOL) implantation in eyes with angle-closure glaucoma (ACG), in eyes with open-angle glaucoma (OAG), and in eyes with no evidence of glaucoma or ocular hypertension.

DESIGN

A comparative, nonrandomized, interventional study.

PARTICIPANTS

Seventy-seven eyes with ACG, 73 eyes with OAG, and 74 control eyes undergoing cataract extraction and IOL implantation.

INTERVENTION

All eyes underwent phacoemulsification and soft acrylic IOL implantation.

MAIN OUTCOME MEASURES

The angle width and depth of the anterior chamber were measured using a Scheimpflug videophotography system before surgery, and at 1 week and at 1, 3, 6, 9, and 12 months after surgery.

RESULTS

Before surgery, the mean anterior chamber angle width and depth in the ACG group was less than that in either the OAG or control groups by approximately 10 degrees in angle width and 1.0 mm in depth (P < 0.0001). After cataract extraction and IOL implantation, the angle width and depth increased significantly in all three groups (P < 0.0001). Although the width and depth in the ACG group were still smaller than that in the other groups, the differences decreased to 2 degrees for angle width and 0.3 mm for depth. In addition, no significant differences were found in these values between the OAG and control groups before or after surgery. Furthermore, no significant changes were observed in the angle width or depth in any of the three groups throughout the postoperative observation period. As expected, the mean preoperative intraocular pressure (IOP) in the ACG and OAG groups was higher than that in the control group. After cataract surgery, however, the mean IOP decreased significantly and was almost the same in all three groups at 1, 6, and 12 months after surgery.

CONCLUSIONS

The width and depth of the anterior chamber angle in eyes with ACG increased significantly after cataract extraction and IOL implantation and became similar to that in eyes with OAG and that in normal eyes, which may lead to the decrease in IOP seen in the postoperative period. No significant changes were observed in angle width and depth in any of the three groups after surgery.

Combined cataract surgery, intraocular lens implantation, and viscocanalostomy

PURPOSE

To describe 2 techniques of combined viscocanalostomy and phacoemulsification and report the results.

SETTING

Gimbel Eye Centre, Calgary, Alberta, Canada.

METHODS

Combined viscocanalostomy, phacoemulsification, and intraocular lens implantation was performed in 83 eyes. A shared scleral incision was made in 46 eyes and a clear corneal incision separate from the viscocanalostomy site, in 37 eyes. A retrospective review of these cases was performed.

RESULTS

Intraocular pressure (IOP) was significantly lower in both groups 2 and 8 weeks and 6 months postoperatively. The decline in IOP postoperatively over time was also comparable. There were no cases of hypotony, choroidal detachment, filtrating bleb, or postoperative cystoid macular edema in either group. Complications included IOP spikes in 2 eyes in the shared-incision group at 1 day (to 43 and 30 mm Hg, respectively). In early shared-incision cases, there was 1 obvious Descement's puncture in 1 eye and a torn scleral flap requiring extra suturing in another eye.

CONCLUSION

Combined viscocanalostomy, cataract extraction, and IOL implantation was safe and efficacious in lowering IOP whether a shared scleral incision or a separate clear corneal incision was used for phacoemulsification.

Management of coincident glaucoma and cataract

Phacoemulsification for visually significant cataract and trabeculectomy for uncontrolled glaucoma are two of the most commonly performed ophthalmic surgeries. Many articles pertaining to cataract extraction in the glaucoma patient have been published during the 1-year scanning period of this periodical. This discussion reviews the recent literature as it pertains to the management of coincident cataract and glaucoma. Important topics addressed by the recent literature include long-standing controversies such as limbus-based versus fornix-based approaches to trabeculectomy and one-site versus two-site approaches to combined surgery, as well as innovative techniques in cataract and glaucoma surgery. This article also addresses perhaps the most controversial issue with regard to coincident cataract and glaucoma surgery, that is, the indications for the procedure. It should be noted that this article is not a comprehensive review but rather discusses the literature published within the 1-year scanning period.