Farnaz Memarzadeh

Blood Pressure, Perfusion Pressure, and Open-Angle Glaucoma: The Los Angeles Latino Eye Study

PURPOSE To examine the cross-sectional relationship between blood pressure, perfusion pressure, and prevalence of open angle glaucoma (OAG) in an adult Latino population. METHODS Participants aged 40 years and older (N = 6130) from the Los Angeles Latino Eye Study (LALES), a large, population-based study of self-identified adult Latinos, underwent an interviewer-administered questionnaire and a complete ocular and clinical examination. Logistic regression was used to evaluate the covariate-adjusted association of OAG with systolic, diastolic, and mean blood pressures and perfusion pressures. Covariates included age, intraocular pressure, history of glaucoma treatment including medications and surgery, and history of blood pressure and treatment of blood pressure including use of medications. RESULTS Low systolic (odds ratio [OR] = 2.5), diastolic (OR = 1.9), and mean (OR = 3.6) perfusion pressures and low diastolic blood pressure (OR = 1.9) were associated with a higher prevalence of OAG in LALES participants. Higher systolic blood pressure and mean arterial blood pressure were associated with a higher prevalence of OAG. There was no relationship between the prevalence of OAG and the presence of a history of cardiovascular disease. CONCLUSIONS Low diastolic, systolic and mean perfusion pressures, low diastolic blood pressure, and high systolic and mean arterial blood pressures are associated with a higher prevalence of OAG in adult Latinos.

Postoperative use of bevacizumab as an antifibrotic agent in glaucoma filtration surgery in the rabbit.

PURPOSE To evaluate the efficacy of bevacizumab as an antifibrotic agent after trabeculectomy in rabbits. METHODS Forty-two rabbits underwent trabeculectomy and were randomly assigned to receive a postoperative course of seven subconjunctival injections of bevacizumab (1.25 mg, 25 mg/mL), 5-fluorouracil (5-FU; 5 mg, 50 mg/mL), or balanced salt solution (BSS; 0.1 mL, control). Bleb survival and characteristics were evaluated over a 30-day period. The animals were killed on postoperative day (PD)10, PD20, and PD30. Histology and immunohistochemistry of the surgical eyes was performed to evaluate and grade the amount of scarring and fibrosis in each group. RESULTS Bevacizumab significantly improved the outcome of filtration surgery in this model. Bevacizumab prolonged bleb survival compared with the 5-FU and control groups (16.0 +/- 1.3 days vs. 6.9 +/- 0.6 and 7.4 +/- 0.85 days, respectively; P < 0.001). Bevacizumab-treated eyes had significantly larger and higher blebs than the control and 5-FU-treated groups (P < 0.05). Histologic analysis revealed that eyes treated with bevacizumab had significantly less postoperative scarring at the microscopic level at PD10 and PD20 (P = 0.009). CONCLUSIONS Postoperative subconjunctival injection of bevacizumab is associated with improved trabeculectomy bleb survival in the rabbit model. Bevacizumab may be a useful agent for improving success and limiting scar tissue formation after trabeculectomy.

Associations with Intraocular Pressure in Latinos: The Los Angeles Latino Eye Study

PURPOSE To evaluate the association of biologic factors with intraocular pressure (IOP) in a Latino population. DESIGN Population-based cross-sectional study. METHODS Latinos 40 years and older (n = 5,958) from the Los Angeles Latino Eye Study without a history of ocular hypotensive treatment underwent an interviewer-administered questionnaire and a complete ocular and clinical examination. IOP was obtained by applanation tonometry and was based on the mean of three measurements. Multivariable regression models were used to evaluate the independent association of biological factors with IOP. RESULTS Higher systolic blood pressure, higher central corneal thickness, and diabetes mellitus were the major factors associated with elevated IOP. Other positively correlated variables included age, female gender, higher diastolic blood pressure, larger body mass index, darker colored irides, and nuclear sclerosis. Axial length and family history of glaucoma had no association with IOP. CONCLUSIONS Several systemic and ocular characteristics are associated with elevated IOP in Latinos. By identifying and recognizing these risk factors, we can define subgroups of the population that may be most at risk of having elevated IOP.

Optical coherence tomography of the anterior segment in secondary glaucoma with corneal opacity after penetrating keratoplasty

Aim: To evaluate secondary glaucoma after penetrating keratoplasty with anterior-segment optical coherence tomography (OCT). Design: Case series. Methods: Four eyes of four patients with corneal opacity and increased intraocular pressure (IOP) were evaluated using high-speed (2000 axial scans/s) OCT at 1.3 μm wavelength. Cross-sectional images of the anterior segment were analysed to assess the cause of increase in pressure. Results: Slit-lamp evaluation of the anterior chamber in all cases was limited by corneal opacity. The OCT imaging allowed visualisation of anterior-segment structures behind the opaque corneas. Using OCT, iris–intraocular lens adhesion and pupillary block were identified as the probable reasons for the increased IOP in one case. Peripheral anterior synechiae and angle closure were identified in the three remaining cases. In two cases, we found that the tip of the aqueous drainage tube was blocked by peripheral anterior synechiae. Conclusions: OCT is similar to ultrasound in that it allows visualisation through opaque corneas. However, OCT has an advantage in that it requires neither contact nor immersion. It is a valuable tool for evaluating the depth of the anterior chamber angle and the causes of secondary angle closure.

Four-year incidence of Open-angle Glaucoma and Ocular Hypertension: The Los Angeles Latino Eye Study

PURPOSE To estimate the 4-year incidence of open-angle glaucoma (OAG) and ocular hypertension (OHT) among adult Latinos 40 years of age and older. DESIGN Population-based longitudinal study. METHODS Comprehensive ophthalmologic examinations including intraocular pressure, visual field testing, and stereoscopic fundus photography were performed at both baseline and the 4-year follow-up examination. Incident OAG at the 4-year follow-up examination was defined as the presence of an open angle and a glaucomatous visual field abnormality or evidence of glaucomatous optic disc damage, or both when not present at baseline. Incident OHT was defined as intraocular pressure of more than 21 mm Hg and the absence of optic disc damage or abnormal visual field results at the 4 year follow-up examination when not present at baseline. RESULTS Among the 3939 participants (mean age, 54.7 ± 10.5 years) with complete data for a diagnosis of glaucoma at both baseline and follow-up examination, incident OAG at the 4-year follow-up was identified in 87 persons (4-year incidence rate, 2.3%; 95% confidence interval, 1.8% to 2.8%). Incident OHT at the 4-year follow-up was identified in 124 persons (4-year incidence rate, 3.5%; 95% confidence interval, 2.9% to 4.1%). In participants with OAG in 1 eye, the 4-year risk of OAG developing in the fellow eye was 5 times as high as the risk for those without OAG in either eye at baseline. In participants with OHT in 1 eye, the 4-year risk of OHT developing in the fellow eye was 10 times as high as the risk for those without OHT in either eye at baseline. The incidence rates of OAG and OHT were higher in older Latinos than in younger Latinos. CONCLUSIONS Incidence of OAG in Latinos is higher than in non-Hispanic whites, but lower than in Afro-Caribbeans. The relatively high rate of incident OAG and OHT underscores the need for community screening programs in this fastest growing segment of the United States population.

Comparison of pterygium recurrence rates in hispanic and white patients after primary excision and conjunctival autograft

Purpose: To evaluate the impact of Hispanic and white ethnicity on the recurrence rates of pterygia after primary excision and conjunctival autograft (CAG) in a southern California population. Methods: A retrospective case-control review comparing 15 Hispanic and 11 white patients with primary nasal pterygia was performed. All participants received pterygium excision with superior limbal CAG by 1 of 3 surgeons and postoperative topical steroids for 2 months. The main outcome measure was recurrence after surgery, defined as fibrovascular tissue over the corneoscleral limbus onto clear cornea in the area of previous pterygium excision. Results: Average duration of follow-up in the Hispanic and white groups were 9.3 ± 9.8 months and 13.0 ± 10.7 months, respectively (P = 0.39). During this follow-up period, there was a statistically significant difference in the pterygium recurrence rate between the Hispanic patients, 6 of 15 (40%), and the white patients, 0 of 11 (0%) (P = 0.02). The average time to recurrence was 3.4 ± 1.1 months (range, 1.9-5.0). The difference in average age, male/female composition, and follow-up time between the Hispanic and white patient groups studied was not found to be statistically significant (P > 0.05). Conclusion: Hispanic ethnicity is a potentially important risk factor for recurrence of primary pterygia treated with CAG.

Assessment of the Anterior Chamber Angle afterTrabectome Glaucoma Surgery by Optical Coherence Tomography, Histopathology,Ultrasound Biomicroscopy, and Scanning Electron Microscopy

To provide high resolution in vitro and in vivo characterization of the post-trabectome anterior chamber angle. We used scanning electron microscopy (SEM) to obtain high resolution images of the post-trabectome angle in cadaver eyes. We then characterized trabecular meshwork strips removed during the procedure using histopathology. Finally,we imaged the post-Trabectome angle in two patients using optical coherence tomography (OCT) and ultrasound biomicroscopy(UBM).