Two Glaucoma Implants Equally Good at 3 Years

The Ahmed glaucoma valve and the Baerveldt glaucoma implant, the 2 most commonly used glaucoma drainage implants in the United States, are equally successful in the treatment of refractory glaucoma, according to the 3-year results of the Ahmed Baerveldt Comparison (ABC) study.

The number of glaucoma drainage implants, according to Medicare database studies, has tripled in the past 20 years, with half of glaucoma specialists using one type of implant and half the other. They are being used based more on surgeon preference than on evidence-based medicine.

The study enlisted the help of 16 centers with glaucoma specialists doing implant surgery and 25 surgeons. The surgeons were asked to randomize patients to receive either the Baerveldt glaucoma implant (model 101-350) or the Ahmed glaucoma valve (model FP7). A total of 276 patients age 18-85 with refractory glaucoma and intraocular pressure (IOP) of 18mmHg or more who were planning to hav ean aqueous shunt were enrolled in the study. At 3-year follow-up, 218 patients (75%) remained in the study.

The study found that the risk for failure by any criterion was similar, however, the risk for reoperation for glaucoma was 2 times higher with the Ahmed implant. The IOP was lower in the patients receiving the Baerveldt implant at 3 years (about 1mmHg lower).

The implants are very different in terms of design. The Ahmed implant has a valve that allows early pressure control, whereas the Baerveldt implant doesn’t. If the patient needs immediate pressure control, the Ahmed implant provides that, whereas the Baerveldt doesn’t. But if you want lower pressures, the Baerveldt implant is more likely to achieve those.


Eye Exam 101

Getting a comprehensive eye exam is an important part of staying healthy. But do you know what the exam should cover?

A comprehensive eye exam is a painless procedure that should check on the following:
• Your medical history — assessed through questions about your vision and family history.
• Your visual acuity — tested by reading a standardized eye chart.
• Your pupils, evaluated to determine how well they respond to light.
• Your eye movement, which is tested to ensure proper eye alignment and ocular muscle function.
• Your prescription for corrective lenses — evaluated to ensure proper vision correction.
• Your side vision, tested for possible vision loss and glaucoma risk.
• Your eye pressure, tested as a possible glaucoma symptom.
• The front part of your eye, examined to reveal any cataracts, scars or scratches on your cornea.
• Your retina and optic nerve — assessed through a dilated eye exam using special eyedrops, which allows your Eye M.D. to thoroughly examine the back of the eye for signs of damage from disease.

Each part of the comprehensive eye exam provides important information about the health of your eyes. Make sure that you are getting a complete examination as part of your commitment to your overall health.

Big Regional Differences in Glaucoma Diagnosis Found

A new analysis of Medicare records finds dramatic differences across the United States in rates of new glaucoma diagnoses, suggesting the eye disease is likely being overdiagnosed in some regions and underdiagnosed in others.

Looking at all Medicare claims for a seven-year period, the team found glaucoma rates had risen slightly overall, but that people in New England or the Mid-Atlantic states had about 30% higher odds than people in the Southeast of being diagnosed with glaucoma-and some 70% higher chances of being diagnosed with suspected glaucoma. The study published in Ophthalmology reports that potentially both physicians and patients in (predominantly rural) areas are not getting the healthcare that would be obtained in a large urban setting such as the New York-Baltimore-Philadelphia area. Lower diagnosis rates in less-urbanized settings may stem from different physician styles in examining patients and detecting glaucoma or fewer eye-care visits by patients, or both.

More than 2.2 million Americans are estimated to have glaucoma, which can lead to blindness. For the new study, researchers examined a random sample of Medicare claims submitted by ophthalmologists, optometrists, and outpatient surgery centers. They looked at claims data from 2002 through 2008, across nine large geographic regions and 179 subregions. The researchers report that the overall prevalence of diagnosed glaucoma increased from 10.4% in 2002 to 11.9% by 2008, largely owing to an increase in suspected open-angle glaucoma diagnoses (from 3.2% to 4.5%). The relative prevalence of diagnosed open-angle glaucoma compared with diagnosed angle-closure glaucoma was 32 to 1. Thuse, acute glaucoma was seriously underdiagnosed.

The New York City area had the highest rates of the condition of all the 179 subregions, which indicated that physicians there were either overdiagnosing it or doing a better job of detecting it. The low rates of diagnosis in all the other areas suggest its’ the latter.

Healthcare providers need to be performing gonioscopy on a regular basis. Women are more likely than men to have the condition and rates of most forms of the condition rose until age 80, and then fell thereafter. This may indicate lack of continuity in care among the very old. Only about 50% of the beneficiaries made an office visit to an optometrist or ophthalmologist in 2008. Blacks, Hispanics and Asians were less likely than non-Hispanic whites to have an eye exam, but they also showed the highest rates of glaucoma and greater risk of developing it.

Fear of Falling Tied to Glaucoma Severity

Visual field (VF) loss resulting from glaucoma is associated with an increased fear of falling, even in people not classified as blind, according to a study published in Ophthalmology. More science needs to be applied to how we train people to walk and to navigate the world. Patients might then be less likely to fall and less likely to bump into things and then eventually be less likely to be fearful, but presently there are no good methods fot that type of training.

The study noted that 50% of people with glaucoma fall over the course of a year, and injuries are more common in this group than in other elderly people. They studied 83 glaucoma subjects with bilateral VF loss, mean age was about 70 years old. All subjects completed the University of Illinois at Chicago Fear of Falling Questionnaire, which includes questions about walking on icy ground, negotiating dark stairs, stepping off a curb, and other circumstances.

Glaucoma was associated with significantly greater fear of falling. This increased with greater VF loss severity. Other variables predicting increased fear included being female, decreased strength and greater comorbid illness.

Long-Term Success of Trabeculectomy May Be High

The performance of trabeculectomy over a 20-year period indicates that this procedure is adequate for controlling intraocular pressure, according to a retrospective cohort study published in Ophthalmology. No previous study has evaluated the long-term efficacy of trabeculectomy and express outcome in terms of complete and qualified success, and blindness factors simultaneously.

Among 330 trabeculectomies performed, 60% of surgeries were classified as complete success, as indicated by a reduction in the intraocular pressure to less than 21 mmHg for high-tension glaucoma or a greater than 20% reduction in intraocular pressure for normal-tension glaucoma without the need for additional medication after 20 years of follow-up. 90% of surgeries were classified as qualified success, as indicated by a reduction in the intraocular pressure to less than 21 mmHg for high-tension glaucoma or a greater than 20% reduction in intraocular pressure for normal-tension glaucoma with the requirement for additional medication after 20 years of follow-up.

Racial Disparities Persist in Glaucoma Testing

Despite a long-standing healthcare initiative to address the issue, people belonging to racial minority groups are less likely to undergo ophthalmologic testing than white people, according to a report presented at the American Glaucoma Society’s 22nd Annual Meeting. Previous studies have shown a higher prevalence of open-angle glaucoma in patients belonging to racial minority groups than whites.

People older than 40 years with atleast 1 year of continuous insurance coverage were included in the analysis. The researchers used these findings to assess black, white, Hispanic, and Asian American male and female cohorts. The records of 149,018 people with open-angle glaucoma were analyzed. Mean age was 61.3 years, 118,062 were white, 15,905 were black, 9376 were Hispanic, 4350 were Asian, and 53.8% were women.

The odds of undergoing visual field testing actually decreased for all racial groups, including whites, from 2001 to 2009, with the largest decreases among Hispanic men (63%) and women (57%). The smallest decrease was among Asian men. In comparison. the odds of undergoing other ocular imaging increased for all groups, increasing the most for black men and women (173%) and the least for Hispanic women (77%). For fundus photography, Hispanic women faired worse than their white counterparts.