Correlation between Intraocular Pressure and Angle Configuration Measured by OCT: The Chinese American Eye Study.
ABSTRACT: PURPOSE:To characterize the relationship between angle configuration measured by anterior segment optical coherence tomography (AS-OCT) and intraocular pressure (IOP). DESIGN:Cross-sectional study. PARTICIPANTS:Subjects aged 50 years or older were identified from the Chinese American Eye Study (CHES), a population-based epidemiological study in Los Angeles, CA. METHODS:Each subject underwent a complete ocular exam including Goldmann applanation tonometry, gonioscopy, and AS-OCT imaging. Four AS-OCT images were analyzed per eye and parameters describing angle configuration were measured, including angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), trabecular iris angle (TIA), and scleral spur angle (SSA). The relationship between AS-OCT measurements and IOP was assessed using locally-weighted scatterplot smoothing (LOWESS) regression and change-point analyses. MAIN OUTCOME MEASURES:Correlation between AS-OCT measurements and IOP. RESULTS:702 eyes (382 closed angle and 320 open angle) from 555 subjects were analyzed. Mean IOP for angle closure eyes was 16.3 ± 3.9 mmHg and open angle eyes was 15.3 ± 2.7 mmHg. Mean IOP increased as AS-OCT measurements decreased for all parameters except TIA750. Once measurement values dropped below parameter-specific threshold values, AS-OCT measurements and IOP were significantly correlated (p < 0.05) for AOD500 (r = -0.416), AOD750 (r = -0.213), ARA500 (r = -0.669), ARA750 (r = -0.680), TISA500 (r = -0.655), TISA750 (r = -0.641), SSA500 (r = -0.538), and SSA750 (r = -0.208). There was no correlation between AS-OCT measurements and IOP in open angle eyes (p > 0.40). CONCLUSIONS:There is an anatomic threshold for angle configuration below which IOP is strongly related to the degree of angle closure. This finding suggests reconsideration of current definitions of angle closure and may be relevant for developing new OCT-based methods to identify patients at higher risk for elevated IOP and glaucoma.
Project description:To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes.Longitudinal cohort study.Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial.Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI.Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images.No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ?0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8-1.6) in treated eyes and 1.6°/year (95% CI, 1.3-2.0) in untreated eyes (P<0.001).Angle width of treated eyes increased markedly after LPI, remained stable for 6 months, and then decreased significantly by 18 months after LPI. Untreated eyes experienced a more consistent and rapid decrease in angle width over the same time period.
Project description:PURPOSE: To report air pressure-induced corneal deformation and iridocornea contact in eyes with primary angle closure (PAC) during intraocular pressure (IOP) measurement performed using a novel noncontact tonometer. METHODS: A single case report. RESULTS: We report a patient with bilateral angle closure. One eye had acute PAC and the other had PAC. The latter was evaluated by the movements of the cornea and iris during IOP measurement using a noncontact tonometer. During the examination, the corneal endothelium and the iris came into contact at the mid-peripheral pupillary area in the left eye with PAC during the corneal reaction to an air puff. In contrast, the corneal endothelium in the pupillary area did not come into contact with the iris. CONCLUSIONS: Although we observed only 1 case and there could be limitations in its interpretation, IOP measurements using a noncontact tonometer may create mechanical stress on the corneal endothelium in eyes with PAC with a very shallow anterior chamber.
Project description:PURPOSE:To evaluate the angle closure scoring system (ACSS) for stratifying primary angle course disease. METHODS:This observational cross sectional institutional study included patients with primary open angle glaucoma suspects (n = 21) and primary angle closure disease (primary angle closure, PAC, n = 63 and primary angle course glaucoma, PACG, n = 58 (defined by International society of Geographical and Epidemiological Ophthalmology, ISGEO). Two independent examiners blinded to clinical details, graded good quality pre-laser goniophotographs of the patients incorporating quadrants of peripheral anterior synechieae (PAS), non-visibility of posterior trabecular meshwork (PTM) and blotchy pigments (ranging from 1-4 quadrants), iris configuration, angle recess (sum of above depicting ACSSg) and lens thickness/axial length ratio (LT/AL), cup disc ratio and baseline intraocular pressure (IOP) to give total score (ACSSt). RESULT:There were significant differences in ACSSg scores within the same ISGEO stage of PAC and PACG between eyes that required nil or >1medicines after laser iridotomy, p<0.001. The ACSSg was associated with need for >1 medicines in both PAC and PACG eyes, p<0.001. An ACSSg score>12 and 14 in PAC (odds ratio = 2.7(95% CI-1.7-5.9) and PACG (Odds ratio = 1.6(95%CI-1.19-2.2) predicted need for single medicines while ACSSg scores >14 and 19 predicted need for ?2 medicines in PAC and PACG eyes, respectively. The LT/Al ratio, IOP score or cup disc score did not influence the need for medical treatment independently. CONCLUSION:The ACSS can be a useful clinical adjunct to the ISGEO system to predict need for medicines and prognosticate each stage more accurately.
Project description:INTRODUCTION:This study evaluates long-term outcomes of two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin in eyes with refractory open angle glaucoma (OAG). METHODS:Prospective ongoing 5-year study of 80 eligible subjects (70 with 4-year follow-up) with OAG and IOP ? 18 mmHg after prior trabeculectomy and while taking 1-3 glaucoma medications. Subjects received two iStent® trabecular micro-bypass stents, one iStent Supra® suprachoroidal stent, and postoperative travoprost. Postoperative IOP was measured with medication and annually following medication washouts. Performance was measured by the proportion of eyes with ? 20% IOP reduction on one medication (the protocol-specified prostaglandin) versus preoperative medicated IOP (primary outcome); and the proportion of eyes with postoperative IOP ? 15 and ? 18 mmHg on one medication (secondary outcome). Additional clinical and safety data included medications, visual field, pachymetry, gonioscopy, adverse events, visual acuity, and slit-lamp and fundus examinations. RESULTS:Preoperatively, mean medicated IOP was 22.0 ± 3.1 mmHg on 1.2 ± 0.4 medications, and mean unmedicated IOP was 26.4 ± 2.4 mmHg. Postoperatively, among eyes without later cataract surgery, mean medicated IOP at all visits through 48 months was ? 13.7 mmHg (? 37% reduction), and annual unmedicated IOP was ? 18.4 mmHg (reductions of ? 30% vs. preoperative unmedicated IOP and ? 16% vs. preoperative medicated IOP). At all postoperative visits among eyes without additional surgery or medication, ? 91% of eyes had ? 20% IOP reduction on one medication versus preoperative medicated IOP. At month 48, 97 and 98% of eyes achieved IOP ? 15 and ? 18 mmHg, respectively, on one medication. Six eyes required additional medication, no eyes required additional glaucoma surgery, and safety measurements were favorable throughout follow-up. CONCLUSION:IOP control was achieved safely with two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin. This microinvasive, ab interno approach introduces a possible new treatment option for refractory disease. TRIAL REGISTRATION:NCT01456390. FUNDING:Glaukos Corporation.
Project description:Purpose:To confirm the relationship between anterior chamber angle (ACA) and intraocular pressure (IOP) early after V4c implantable collamer lens (ICL) implantation. Methods:Patients were assigned to two groups: (1) right eyes (control group) and (2) left eyes (experimental group), with miosis conducted immediately after ICL implantation in the left eyes. IOP, angle opening distance (AOD), trabecular-iris angle (TIA), and pupil diameter (PD) were compared between two groups at postoperative hours 1, 2, and 24. The relationship between ACA, PD, and IOP was analyzed by multiple linear regression. Result:Thirty-six eyes of 18 patients were enrolled. The prevalence of ocular hypertension (OHT, defined as IOP???21?mmHg) was 61.11% and 16.67% in the right and left eyes, respectively, (? 2?=?7.481, p=0.006). At postoperative hours 1 and 2, IOP and PD were significantly higher (p < 0.001) in the right eyes, and TIA and AOD were significantly lower (p < 0.05) in the right eyes than in the left eyes. There was no significant difference at 24?h postoperative in these parameters. After the right eye ICL implantation, the changes of AOD 500 and PD were both linearly correlated with postoperative IOP change (??=?-23.707 and 1.731, respectively; p?=?0.013 and 0.002, respectively). Conclusion:The ACA was significantly narrowed immediately after V4c ICL implantation. There was a negative linear correlation between ACA and early IOP and a positive linear correlation between PD and early IOP. We recommend the use of intracameral miotics immediately after V4c ICL implantation to reduce the incidence of IOP spikes.
Project description:Purpose. To evaluate efficacy and safety of a trabecular micro-bypass stent system when used as the sole procedure in Japanese patients with medically uncontrolled primary open-angle glaucoma (POAG). Design. Prospective nonrandomized interventional pilot study. Methods. Ten eyes of 10 Japanese patients with medically uncontrolled POAG taking three ocular hypotensive medications were treated using only the implantation of two iStent trabecular micro-bypass stents. Each patient continued to take the same ocular hypotensive medications used preoperatively throughout the study. Intraocular pressure (IOP) and endothelial cell density (ECD) were determined at baseline and at 1, 3, and 6 months postoperatively. Best-corrected visual acuity (BCVA) was measured at baseline and 6 months after surgery. Results. Mean IOP was 22.0 ± 3.0?mmHg at baseline and 16.9 ± 3.6?mmHg at 6 months, which represented a mean reduction of 5.1?mmHg or 23.2%. No significant changes were observed in the ECD and BCVA. Complications that occurred during the early postoperative period included hyphema, peripheral anterior synechiae, and occlusion of the stent by the iris. Conclusion. Implantation of two trabecular micro-bypass stents as the sole procedure in Japanese POAG patients effectively reduced IOP and exhibited a favorable safety profile. Clinical Trials Registration number is UMIN000004002.
Project description:The study objective was to evaluate the intraocular pressure (IOP) and medication-lowering effect of 2 second-generation trabecular micro-bypass stents in eyes with open-angle glaucoma (OAG) on one preoperative medication.Fifty-seven qualified phakic eyes with OAG on 1 medication, preoperative medicated IOP of 18-30 mmHg, and preoperative unmedicated (post-washout) IOP of 22-38 mmHg underwent implantation of 2 second-generation trabecular micro-bypass stents in a standalone procedure. Evaluations included IOP, best-corrected visual acuity, medication use, fundus and slit lamp examinations, visual field, cup to disc ratio, pachymetry, and complications and interventions. Subjects have been followed for 18 months, and follow-up is ongoing.At Month 12 postoperative, 100% of eyes had achieved an IOP reduction ?20% (100% had IOP ?18 mmHg and 67% had IOP ?15 mmHg) without medication versus preoperative unmedicated IOP, and 75% had IOP reduction ?20% without medication versus preoperative medicated IOP. The Month 12 mean unmedicated IOP had decreased by 42%, to 14.2 ± 1.9 mmHg vs 24.4 ± 1.3 mmHg preoperatively, and this reduction was maintained through 18 months (14.4 ± 2.1 mmHg). A high safety profile was observed.In this prospective, open-label, single-arm study, the standalone implantation of two second-generation trabecular micro-bypass stents in OAG patients on 1 preoperative medication resulted in IOP reduction to ?15 mmHg and elimination of medication through 18 months, with favorable safety.ClinicalTrials.gov identifier, NCT02868190.Glaukos Corporation, San Clemente, CA.
Project description:PURPOSE:To examine outcomes through 36 months in phakic eyes with newly diagnosed primary open-angle glaucoma (POAG) naïve to therapy randomized to treatment with two trabecular micro-bypass stents or topical prostaglandin. METHODS:Subjects with POAG naïve to therapy, with intraocular pressure (IOP) ?21 and ?40 mmHg, were randomized to implantation of two stents or travoprost. Additional medication was to be prescribed post-treatment for elevated IOP or glaucomatous optic nerve findings. Of 101 randomized subjects, 100 subjects were followed for 24 months and 73 subjects were followed for 36 months. Follow-up on all subjects is ongoing. RESULTS:In this randomized cohort of 101 POAG subjects, 54 subjects underwent 2-stent surgery and 47 received topical travoprost. Mean pre-treatment IOP was 25.5 ± 2.5 mmHg in stent-treated eyes and 25.1 ± 4.6 mmHg in medication-treated eyes. By 3 years, mean IOP was 14.6 mmHg in stent eyes (with medication added in 6 eyes) and 15.3 mmHg in travoprost eyes (with a second medication added in 11 eyes). In the subset of eyes that did not require additional medical therapy, mean IOP was 14.5 mmHg and 15.7 mmHg in the respective groups. Ninety-one percent of stent eyes had 3-year IOP ?18 mmHg without additional therapy (62% ? 15 mmHg) and 79% of travoprost eyes had 3-year IOP ?18 mmHg (21% ? 15 mmHg). Safety was favorable in both groups. CONCLUSIONS:In this prospective, randomized comparison of subjects with newly diagnosed POAG naïve to therapy, substantial IOP reduction with a favorable low complication rate was shown through 3 years after either 2 trabecular stents implanted as the sole procedure or topical travoprost therapy. These data suggest 2-stent implantation may be a viable initial treatment option comparable to topical prostaglandin in newly diagnosed POAG patients. TRIAL REGISTRATION:ClinicalTrials.gov identifier, NCT01443988. FUNDING:Glaukos Corporation, Laguna Hills, CA.
Project description:Purpose:Our purpose is to describe a 60-year-old male, who has plateau iris configuration and developed bilateral ciliochoroidal effusion syndrome after ingestion of acetazolamide. Observations:Our case was a research participant in a multi-center clinical study (ClinicalTrials.gov NCT01677507). During the course of this study, he was treated with a single dose of acetazolamide (500 mg), and seven days later treated with latanoprost one drop daily at bedtime both eyes for seven days, and then was administered another dose of acetazolamide (500 mg). Several hours later he complained of blurred vision in the distance and mild headache. On examination, he had a myopic shift, intraocular pressures of 36 mmHg in right eye and 35 mmHg in left eye, shallow anterior chambers both eyes, and occluded angles by gonioscopy both eyes. An echographic exam confirmed the bilateral ciliochoroidal effusion syndrome. He was treated by no further dosing of acetazolamide and started on timolol, atropine and prednisolone. Two weeks later, the bilateral choroidal effusion and acute angle closure were resolved. Repeat echography showed plateau iris configuration. Conclusions and Importance:To the best of our knowledge, drug-induced bilateral ciliochoroidal effusion syndrome has not been reported with acetazolamide in plateau iris configuration.
Project description:PURPOSE: The purpose of this study is to quantify anterior chamber (AC) parameters and to determine the proportion of eyes with exaggerated lens vault (LV) in different subtypes of angle closure disease using anterior segment optical coherence tomography (AS-OCT). PATIENTS AND METHODS: In this prospective study, 115 eyes of 115 Iranian patients with angle closure disease were included and categorized into three groups: (1) fellow eyes of acute angle closure (AAC; 40 eyes); (2) primary angle closure glaucoma (PACG; 39 eyes); and (3) primary angle closure suspect (PACS; 36 eyes). Complete ophthalmic examination including gonioscopy, A-scan biometry, and AS-OCT were performed. Angle parameters, LV, and iris thickness (IT) were measured using AS-OCT. An exaggerated LV was defined as LV more than one-third the distance between the corneal endothelium and a line drawn to connect the nasal and temporal scleral spurs. RESULTS: Fellow eyes of AAC had the shallower AC (P=0.01), greater iris curvature (I-curve; P=0.01), and higher LV (P=0.02) as compared with PACS and PACG eyes. There was no statistically significant difference in the mean IT at 750 μm from scleral spur among the three groups (P=0.45). Exaggerated LV was found in 67.5, 35.9, and 40% of fellow eyes of AAC, PACG, and PACS, respectively, (P=0.008) with an odds ratio of 1.92 (P=0.005) for fellow vs PACG and 1.68 (P=0.01) for fellow vs PACS. CONCLUSIONS: Exaggerated LV is highly prevalent in fellow eyes of AAC. These eyes have shallower AC depth, greater I-curve, and higher LV when compared with PACG and PACS.