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Journal Highlights
New Findings from Ophthalmology, AJO and Archives
 
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Ophthalmology:

American Journal of Ophthalmology:

Archives of Ophthalmology:

Roundup of Other Journals:

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Ophthalmology

Photodynamic Therapy for Patients With Choroidal Metastasis
Ophthalmology
Published online March 5, 2012

In a retrospective, interventional case series of eight patients, Kaliki et al. found that photodynamic therapy (PDT) delivered satisfactory control of seven of nine small- to medium-sized choroidal metastases. In addition, visual acuity was preserved in seven of eight eyes. The only side effect identified by the authors was a minor PDT-related intraretinal hemorrhage in one eye.

The treatment consisted of one PDT session for eight of the tumors and two sessions for one tumor. The PDT was conducted using verteporfin at a dose of 6 mg/m2 of body surface area and 689-nm diode laser at an intensity of 600 mW/ cm2 for 83 seconds. The two tumors that failed to respond to PDT required plaque radiotherapy.

The authors note that one major benefit of using PDT is that the procedure is performed in an outpatient setting, thus sparing the patient hospitalization and interventional surgery. The authors recommend further studies in a large cohort with a focus on long-term results.


Physical Activity of Glaucoma Patients With Visual Field Loss
Ophthalmology
Published online March 2, 2012

Ramulu et al. quantified the degree to which glaucomatous visual field (VF) impacts physical activities performed during a patient’s typical day. The researchers did not find a statistically significant difference in median physical activity levels between glaucoma suspects without VF loss and glaucoma patients with bilateral VF loss. However, subgroup analysis showed differences when patients were divided into tertiles according to severity of damage in the better eye.

The 58 glaucoma suspects and 83 glaucoma patients (60 to 80 years old) wore an accelerometer during seven days of normal activity. The researchers measured daily minutes of moderate or vigorous physical activity; the secondary measure was steps taken per day.

Glaucoma patients whose better-eye VF fell into the most severe tertile participated in 66 percent less activity than the glaucoma suspects, and they took 31 percent fewer steps per day. Secondary analyses revealed that even a 5-dB better-eye decrement was significantly associated with a decrease in physical activity.

Given the decrease in physical activity in patients with advanced bilateral VF loss as well as the health risks associated with this lack of movement, the authors call for further studies focusing on the relationship between glaucoma and physical activity.


Second-Eye Refractive Error Improvements in Bilateral Sequential Cataract Surgery Patients
Ophthalmology
Published online March 2, 2012

Jivrajka et al. looked at the challenge of improving the second-eye refractive error in patients undergoing bilateral sequential cataract surgery when their first-eye refractive error (FERE) exceeded 0.5 D. The researchers found that the refractive error of the second eye could be improved by modifying the IOL power to correct up to 50 percent of the error from the first eye.

Specifically, their findings showed that in eyes with high interocular correlation and in eyes where the FERE exceeds 0.5 D, a partial adjustment during the IOL power calculation of the fellow eye might help enhance the final outcome of the bilateral sequential cataract surgery.

The prospective, observational case series included 250 patients who underwent first-eye cataract operations and were scheduled one to three months later for their second-eye surgery. When choosing the IOL power for the second eye, the investigators adjusted the calculations to correct 50 percent of the FERE. They then evaluated the adjusted second-eye refractive error six to eight weeks following surgery.

One limitation of the study noted by the authors was that only one IOL power formula was used—the Haigis formula—and thus postoperative refractive outcomes with other formulas were not considered.


American Journal of Ophthalmology

Immunologic Graft Rejection Following DSAEK
May’s AJO

Wu et al. performed a retrospective study to investigate the clinical features of, risk factors for, and treatment outcomes after immunologic graft rejection in eyes that have undergone Descemet stripping automated endothelial keratoplasty (DSAEK).

The authors found that, in contrast to penetrating keratoplasty, rejection following DSAEK is almost exclusively endothelial. Among risk factors traditionally associated with graft rejection, cessation of topical steroids was the most significant.

The researchers reviewed the charts of 353 DSAEK patients. Cases with at least three months of follow-up were included in the study. Thirty of the 353 DSAEKs developed graft rejection. Kaplan-Meier rate of rejection was 6 percent at one year, 14 percent at two years, and 22 percent at three years. Rejection episodes occurred between 0.8 and 34 months.

Clinical findings included anterior chamber cells, keratic precipitates, endothelial rejection line, and vascularization at the host-donor interface. Risk factors for graft rejection were cessation of postoperative steroid and black race; factors that were not associated with rejection included recipient age, sex, surgical indication, glaucoma, postoperative steroid response, corneal neovascularization or peripheral anterior synechiae, graft size, prior keratoplasty in fellow eye, and concurrent or subsequent procedures. Twenty-two of 30 rejection episodes resolved with steroid treatment.


Diagnostic Capability of SD-OCT for Glaucoma
May’s AJO

In a prospective, cross-sectional study, Wu et al. analyzed the diagnostic capability of the Spectralis spectral-domain optical coherence tomography system (Heidelberg) in glauco ma patients with visual field defects. They found that statistical parameters for evaluating the diagnostic performance of Spectralis SD-OCT were good for early perimetric glaucoma and excellent for moderately advanced perimetric glaucoma.

The authors randomly selected one eye each of 85 normal subjects and 61 glaucoma patients with average visual field mean deviation of –9.61 ± 8.76 dB. They calculated a subgroup of the glaucoma patients with early visual field defects separately and performed OCT circular scans to obtain peripapillary retinal nerve fiber layer (RNFL) thicknesses.

The authors also used the RNFL diagnostic parameters based on the normative database alone or in combination with one another for identifying glaucomatous RNFL thinning. In order to evaluate diagnostic performance, calculations included areas under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio.

Overall RNFL thickness had the highest areas under the receiver operating characteristic curve value: 0.952 for all patients and 0.895 for the early glaucoma subgroup. For all patients, the highest sensitivity (98.4 percent) was achieved by using two criteria: more than one RNFL sector being abnormal at the less than 5 percent level, and overall classification of borderline or outside normal limits.


Five-Year Results of the Tube Versus Trabeculectomy Study
May’s AJO

Gedde et al. found that tube shunt surgery had a higher success rate than did trabeculectomy with mitomycin C (MMC) during five years of follow-up. Both procedures were associated with similar IOP reduction and use of supplemental medical therapy at five years. Additional glaucoma surgery was needed more frequently after trabeculectomy with MMC than after tube shunt placement.

This study included patients 18 to 85 years of age who had previous trabeculectomy and/or cataract extraction with IOL implantation and uncontrolled glaucoma with IOP of greater than 18 mmHg and less than 40 mmHg on maximum tolerated therapy. Tube shunt (350-mm2 Baerveldt glaucoma implant [AMO]) or trabeculectomy with MMC (0.4 mg/mL for four minutes) were the variables.

The researchers enrolled 212 eyes of 212 patients, with 107 in the tube group and 105 in the trabeculectomy group. At five years, mean IOP was 14.4 mmHg in the tube group and 12.6 mmHg in the trabeculectomy group. The mean number of glaucoma medications was 1.4 in the tube group and 1.2 in the trabeculectomy group. The cumulative probability of failure during five years of follow-up was 29.8 percent in the tube group and 46.9 percent in the trabeculectomy group. The rate of reoperation for glaucoma was 9 percent in the tube group and 29 percent in the trabeculectomy group.


Archives of Ophthalmology

Cost-Effectiveness of Prostaglandin Analogues and Laser Trabeculoplasty
April’s Archives

Stein et al. assessed the relative cost-effectiveness of generic prostaglandin analogues (PGAs) or laser trabeculoplasty (LTP) as the initial treatment strategy for patients with newly diagnosed mild open-angle glaucoma. They found that both treatments can be highly cost-effective and that patient adherence plays an important role in influencing which treatment is ultimately the more cost-effective alternative.

The authors projected out the costs and health consequences over a 25-year time horizon for a theoretical cohort of patients, starting at age 60, with newly diagnosed open-angle glaucoma treated with observation only, generic PGAs, or LTP. Incremental cost-effectiveness and cost per quality-adjusted life-year (QALY) were derived for each of the three treatment groups.

The authors found both LTP and PGAs to be highly cost-effective at $16,824/QALY and $14,179/QALY, respectively, when assuming excellent medication adherence. However, additional analysis revealed that if PGAs are 25 percent less effective at lowering IOP because of suboptimal patient adherence, LTP may be the more cost-effective treatment option.


Three-Year Outcomes of the Surgery for Trichiasis, Antibiotics to Prevent Recurrence Trial
April’s Archives

Woreta et al. reported the three-year results of the Surgery for Trichiasis, Antibiotics to Prevent Recurrence (STAR) trial. They found that trichiasis recurrence rates in the trial remained low for up to three years following surgery. The protective effect of a single dose of azithromycin was superior to topical tetracycline for up to one year and was still evident up to three years following trichiasis surgery.

The researchers randomized 1,452 patients in southern Ethiopia who underwent surgery for trichiasis to receive either a single 1-g dose of oral azithromycin or twice-daily topical tetracycline for six weeks. Previously, West et al. reported one-year results showing that oral azithromycin reduces the risk of trichiasis recurrence by 33 percent compared with topical tetracycline. In this three-year follow-up study, the oral azithromycin group had a 22 percent lower rate of trichiasis recurrence than the tetracycline group, but this difference did not reach statistical significance.


Relationship of Fuchs Endothelial Corneal Dystrophy to Central Corneal Thickness
April’s Archives

Kopplin et al. examined the relationship between the severity of Fuchs endothelial corneal dystrophy (FECD) and central corneal thickness (CCT) in subjects from the NEI-funded FECD Genetics Multi-Center Study cohort. The researchers found that an increase in CCT accompanies increasing severity of FECD, even when edema is not clinically apparent. They noted that monitoring CCT changes serially could be a sensitive measure of disease progression.

The researchers examined 1,610 eyes from a subset of severely affected FECD cases, family members, and unrelated control subjects with normal corneas. The association between FECD severity grade and CCT was determined by a multivariable model adjusted for age, race, sex, history of glaucoma or ocular hypertension, diabetes mellitus, contact lens wear, IOP, and familial relationship to the index case. The researchers used the interaction between FECD severity grade and edema on slit-lamp exam to investigate whether the effect of FECD severity grades on CCT differed between those with and without edema.

Average CCT was thicker in index cases for all FECD grades than in unaffected controls, and thicker in affected family members with an FECD grade of four or greater than in unaffected family members. Similar results were observed for subjects without edema. Average CCT of index cases was also greater than that of affected family members with comparable grades of four, five, and six FECD.
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Ophthalmology summaries are written by Lori Baker Schena, EdD, and edited by John Kerrison, MD. American Journal of Ophthalmology summaries are edited by Thomas J. Liesegang, MD. Archives of Ophthalmology summaries are written by the lead authors.


Roundup of Other Journals

Effect of IOL Tilt and Decentration on IOLs After LASIK
Journal of Refractive Surgery
Published online March 12, 2012

Ruiz-Alcocer et al. used adaptive optics technology to simulate the effect of IOL tilt and decentration with three different lenses in 10 patients in the setting of hyperopic ablation with LASIK. They found that the visual impact of IOL misalignment was greatest in eyes with higher amounts of hyperopic ablation and that it varied according to lens design.

The researchers used a visual simulator to simulate the wavefront aberration pattern of the AcrySof IQ aspheric IOL (Alcon) and the Akreos Adapt (Bausch + Lomb) and Triplato (AJL Ophthalmics) spherical IOLs, which have different amounts of positive spherical aberration. They performed these simulations in five situations: centered, 0.2 and 0.4 mm of decentration, and 2 and 4 degrees of tilt. They compared data between two groups: simulated low hyperopic laser corneal ablation (low hyperopia group) and high hyperopic laser corneal ablation (high hyperopia group).

When the IOLs were centered, visual results were similar for all three lenses in the low hyperopia group; but in the high hyperopia group, VA was better with the Akreos Adapt and the AcrySof IQ than with the Triplato. When the lenses were misaligned, visual quality declined in both high and low groups, except for the low hyperopia patients using the Akreos Adapt. Among the various misalignment scenarios, 0.4 mm of decentration caused the greatest decrease in VA for all of the lenses, and the high hyperopia group was more sensitive to misalignment than the low group.

The Akreos Adapt was the one IOL least affected by misalignment in both patient groups, perhaps because this IOL’s higher positive spherical aberration compensates for the negative aberration introduced through hyperopic ablations.


Systemic Immunosuppression Protocol in Ocular Surface Stem Cell Transplantation
Cornea
Published online Feb. 13, 2012

Holland et al. described their 10-year experience using a systemic immunosuppression protocol in patients undergoing ocular surface stem cell transplantation; they stress that prevention of graft rejection should be approached with the same diligence as in solid organ transplantation. The authors also note that the risk of irreversible toxicity from systemic immunosuppression can be minimized with vigilant long-term monitoring by both a cornea specialist and a transplant physician.

The authors performed a retrospective analysis on all patients who underwent ocular surface stem cell transplantation from 1997 to 2007 and/or received their systemic immunosuppression at the Cincinnati Eye Institute. The steroid-minimizing immunosuppression protocol included the use of combined mycophenolate mofetil, tacrolimus, and a short course of prednisone in 102 of the 136 patients (225 eyes) involved in the study. The investigators also used prophylactic valganciclovir and trimethoprim/sulfamethoxazole (or dapsone if the patient had a sulfa allergy). The mean duration of the immunosuppression was 42.1 months, and the mean follow-up time after ocular surface stem cell transplantation was 53.9 months. At the final follow-up visit, 77.2 percent of patients had a stable ocular surface. Two patients experienced three severe adverse events, and 19 patients had 21 minor adverse events.


Retinal Optical Imaging to Detect Amyloid-b Protein in Alzheimer Disease
Neurodegenerative Diseases
Published online Feb. 10, 2012

Using retinal imaging in animal models of Alzheimer disease, Koronyo et al. demonstrated the ability to monitor in vivo amyloid-ß (Aß) protein formation and clearance following immunotherapy. The authors note that this finding has the potential to eventually translate into a clinical tool to detect and assess the disease progression in humans—especially given that the existence of Aß plaque pathologies in the retinas of Alzheimer’s patients has been found to be comparable to that observed in their brains. And, unlike the brain, the retina can be easily imaged in a noninvasive manner.

This research provides the first proof-of-concept evidence for monitoring dynamic changes occurring in individual retinal Aß plaques in response to glatiramer acetate immunotherapy in live amyloid precursor protein transgenic mice. They call for future studies to validate that retinal plaques are indeed an early biomarker of Alzheimer disease, to show that these retinal plaques actually mirror the disease’s progression in the brain, and to standardize them in correlation to other biomarkers of the disease.
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Roundup of Other Journals is written by Lori Baker Schena, EdD, and edited by Deepak P. Edward, MD.


More Online


Read the latest published research at
the following websites:

Ophthalmology
www.aaojournal.org

American Journal of Ophthalmology
www.ajo.com

Archives of Ophthalmology
archopht.ama-assn.org

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