Lens surgery to treat open-angle glaucoma: triumph of hope over (evidence-based) experience

Changes in glaucoma medication numbers after cataract and glaucoma surgery: A nationwide population-based study

To determine whether cataract or glaucoma and combined cataract and glaucoma surgery (CGS) affect glaucoma medication usage.We recruited patients who received new diagnoses of glaucoma, either primary open-angle glaucoma (POAG) (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 365.1) or primary angle-closure glaucoma (PACG) (ICD-9-CM code 365.2), between 1998 and 2011 and had undergone cataract surgery alone (CS), glaucoma surgery alone (GS), or CGS under the National Health Insurance program in Taiwan. CS, GS, and CGS in all the patients were performed after the glaucoma diagnosis date. The patients were subdivided into CS, CGS, and GS groups. The number of glaucoma medications, including prostaglandin analogs, β-blockers, carbonic anhydrase inhibitors, α-agonists, pilocarpine, and a combination of drugs, in each prescription, were compared before and after surgery.The mean number of glaucoma medications in each prescription before the surgery increased from approximately 0.5/1 (CS/CGS + GS) to a peak of 1.75/3 within 3 months before the index date. The mean number of glaucoma medications in each prescription reduced to 0 (CS group) and to approximately 0.5 (CGS and GS) at the end of the 3-year follow-up period. The mean number of glaucoma medications in each prescription significantly reduced at the time points within 6 months, between 6 months and 2 years, and during 2 to 3 years after surgery in each group. At the end of the 3-year period, the reduction effect was most evident in the CS group. Similar trends were also observed in the POAG and PACG group.CS, GS, and CGS significantly reduced the number of glaucoma medications used by the glaucoma patients.

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.