Preoperative Intraocular Pressure Levels Research Articles

Factors leading to reduced intraocular pressure after combined trabeculotomy and cataract surgery.

To determine the factors that control intraocular pressure (IOP) after trabeculotomy combined with phacoemulsification and intraocular lens implantation as an initial procedure in adults with primary open-angle glaucoma (POAG). A consecutive series of 141 eyes with POAG or ocular hypertension was prospectively recruited. One hundred five eyes were treated by combined trabeculotomy and cataract surgery (TPI group) and 36 eyes were treated by cataract surgery alone (PI group). The prognostic factors that correlate with successful IOP control after surgery were screened using the Cox multivariate analyses based on three definitions of success: IOP <21 mm Hg, <17 mm Hg, and <15 mm Hg, with or without eye drops. The factors examined were types of procedure (TPI or PI), age, sex, preoperative IOP level, number of preoperative antiglaucoma medications, eyes with high myopia (>-10 diopters), postoperative hyphema lasting longer than 4 days, and postoperative transient IOP spike (>30 mm Hg). TPI was a significant factor for IOP reduction in the three definition-based multivariate analyses. Other factors included patient age, preoperative IOP level, and postoperative IOP spike. The statistical significance of age was further confirmed using linear regression analysis and the Spearman correlation coefficient (Rs) between age and IOP level 3 months after surgery (R(2)=0.13, P = 0.0002 and Rs=-0.44, P < 0.0001, respectively in the TPI group). The success rates for IOP control <17 mm Hg and <15 mm Hg were significantly higher in patients 70 years and older than in younger patients, as determined using the Kaplan-Meier life table analysis with the Mantel-Cox logrank test in both TPI and PI groups. IOP reduction was significantly greater in older patients than in younger patients at every follow-up visit for up to 1.5 years for the TPI group and up to 1 year for the PI group. Advanced age is a favorable prognostic factor for successful control of IOP after combined trabeculotomy and cataract surgery. Older patients with POAG and visually significant cataract are good candidates for combined trabeculotomy and cataract surgery.

Transscleral suture fixation of posterior chamber lenses combined with trabeculectomy.

To evaluate the outcome of transscleral suture-fixated posterior chamber intraocular lens (PCIOL) implantation in glaucoma patients when combined with a trabeculectomy. A retrospective study of 56 consecutive glaucoma patients with a minimum follow-up of 6 months after transscleral suture-fixated PCIOL implantation combined with trabeculectomy. Patients were drawn from the clinical glaucoma practice of the Kresge Eye Institute, Detroit, MICHIGAN: Fifty-six eyes of 56 consecutive chronic glaucoma patients who had undergone transscleral suture-fixated PCIOL implantation in combination with a trabeculectomy were included in the analysis. The mean follow-up time was 38.5 +/- 19.1 months. Mean intraocular pressure (IOP) was significantly reduced, from 22.9 +/- 10.9 mmHg before surgery to 16.7 +/- 6.7 mmHg at the last follow-up visit (P = 0.0005), with the mean number of medications used also significantly decreased, from 2.3 +/- 0.9 to 1.9 +/- 0.9 (P = 0.0002). Postoperative IOP control to 21 mmHg or less was achieved or maintained in 84% of patients. Visual acuity improved or remained stable within two Snellen lines of the preoperative level in 39 eyes (70%) and within three Snellen lines in 45 eyes (80%) at the last follow-up visit. Overall, 46% to 68% of the patients had both stable visual acuity and satisfactory pressure control at the last postoperative visit, depending on criteria of varying stringency. However, 19 eyes (34%) required one or more additional surgical interventions for pressure control. Patients with anterior chamber intraocular lens (ACIOL) complications, diabetes mellitus, or a preoperative IOP level of more than 21 mmHg on maximum tolerated medications were especially prone to requiring additional surgical interventions. We conclude that transscleral suture-fixated PCIOL implantation can be combined successfully with a trabeculectomy and can be useful in glaucoma patients in need of both visual rehabilitation and IOP control. However, patients with ACIOL complications, diabetes, or preoperative IOP of more than 21 mmHg on maximum tolerated medications were prone to requiring additional surgical interventions.

Long-term follow-up of Nd:YAG laser posterior capsulotomy

A Nd:YAG laser developed for ophthalmic surgery was studied for safety and efficacy in secondary discission of the posterior capsule in aphakic and pseudophakic subjects. The study involves 6,800 subjects, 526 of whom had completed the six-month postoperative course by the time the data base was closed for analysis. Of the 526 subjects who were treated with the laser, 87.8% had improved vision, with 82.9% achieving a visual acuity of 20/40 or better. This result compares favorably with results for the surgically treated population in which only 68.4% experienced improved vision, with 80.2% achieving a visual acuity of 20/40 or better. Approximately four times more surgically treated subjects than laser-treated subjects experienced diminished vision (14.8%).Cumulative complication rates in the laser-treated population were very low (CME 2.3%, secondary glaucoma 3.6%, retinal detachment 0.4%, overall rate 4.8%). Persistent complications (present at the six-month postoperative period) were present at an overall incidence of 2.3%, comprised primarily of CME, 0.2%, retinal detachment, 0.2%, and secondary glaucoma, 0.8%. Only 5.7% of subjects experienced an intraocular pressure (IOP) rise to 30 mm Hg or greater. Return to the preoperative IOP level occurred in 89% of subjects in the first 24 hours to one week. Predictors of IOP rise to 30 mm Hg or greater were determined to be preoperative glaucoma and/or preoperative IOP of greater than 20 mm Hg.