By Brooke Strickland

In this study, researchers wanted to measure the safety and effectiveness of low-voltage, external-beam, stereotactic radiotherapy (SRT) for patients diagnosed with neovascular age-related macular degeneration (AMD). The study included 230 randomized patients from various centers. They had all been diagnosed with neovascular AMD and had received ≥3 ranibizumab or bevacizumab injections within the previous year. They all required treatment at enrollment. Participants received 16 Gray, 24 Gray, or sham SRT. All arms received pro re nata (PRN) ranibizumab for 12 months, with PRN bevacizumab or ranibizumab thereafter. Researchers noted the average number of PRN injections, best-corrected visual acuity (BCVA), loss of <15 Early Treatment of Diabetic Retinopathy Study letters, change in optical coherence tomography central subfield thickness, and variation in angiographic total lesion area and choroidal neovascularization (CNV) area.

Results showed that at the two year mark, the 16 and 24 Gray arms received fewer PRN treatments compared with sham. Change in average BCVA was −10.0, −7.5, and −6.7 letters for the 16 Gray, 24 Gray, and sham arms, with 46 (68%), 51 (75%), and 58 participants (79%) losing <15 letters. Mean central subfield thickness decreased by 67.0 μm, 55.4 μm, and 33.3 μm. Average total active lesion area increased by 1.0, 4.2, and 2.7 mm2, respectively. Average CNV area reduced by 0.1 mm2 in all groups. An independent reading center noticed microvascular abnormalities in 6 control eyes and 29 SRT eyes, of which 18 were credited to radiation; however, only 2 of these possibly affected vision. An exploratory subgroup analysis found that lesions with a greatest linear dimension ≤4 mm (the size of the treatment zone) and a macular volume greater than the median (7.4 mm³) were more responsive to SRT, with 3.9 PRN injections versus 7.1 in comparable sham-treated participants. (1)

What to take away from the study: A single dose of SRT can considerably reduce intravitreal injections over a two year time span. Radiation can help with microvascular change, but approximately only 1% of patients will see a change in vision. The best response is when AMD lesions are leaking and fit within the treatment zone.

1. 1. Jackson, Timothy, L., PhD, FRCOphth, Chakravarthy, Usha, MD, PhD, Slakter, Jason, S., MD, Muldrew, Alyson, PhD, Shusterman, E. Mark, MD, O’Shaughnessy, Denis, PhD, Arnoldussen, Mark, PhD, Gertner, Michael, E., MD, Danielson, Linda, MSc, Moshfeghi, Darius, M., MD on the behalf of INTREPID Study Group. “Sterotactic Radiotherapy for Neovascular Age-Related Macular Degeneration.” Ophthalmology. Published online September 7, 2014. Accessed online September 12, 2014. http://www.aaojournal.org/article/S0161-6420%2814%2900687-3/abstract

 

 

By Brooke Strickland

In this study, researchers looked to determine what types of pediatric retinal degeneration are linked with inflammatory cells in the anterior vitreous. They looked at 105 charts of pediatric patients that had suspected retinal degeneration in a 5 year time frame (2008-2013). They noted age, visual acuity (VA), slit-lamp examination of anterior vitreous (SLAV), and clinical and molecular genetic diagnoses. Anterior vitreous cells were graded clinically with SLAV from rare cells (1–4) to 1+ (5–9), 2+ (10–30), or 3+ (>30).

Results showed that 68 patients (64.8%) included SLAV data. Numerous (1+ or greater) cells were seen in 22 of 68 patients (32.4%). There were four patients (5.9%) that had rare cells and 42 (61.8%) showed no cells. The average age between these 3 groups of patients did not differ significantly. The visual acuity was noted as an average of 20/124 for patients with cells, 20/143 for patients with no cells, and 20/68 for patients with rare cells. The most common diagnoses for patients with cells were Bardet Biedl syndrome (BBS), Leber congenital amaurosis (LCA), and retinitis pigmentosa. For the patients with no cells, they were most commonly diagnosed with blue cone monochromacy, congenital stationary night blindness (CSNB), LCA, and Stargardt disease.

What to take away from the study: This study showed that pediatric retinal degenerations can show whether or not inflammation is also associated with progressive vision loss in various subtypes.

1. Stunkel, Maria, BS, Bhattarai, Sajag, MS, Kemerley, Andrew, BS, Stone, Edwin, M., MD, PhD, Wang, Kai, PhD, Mullins, Robert, F., PhD, Drack, Arlene, V., MD. “Vitritis in Pediatric Genetic Retinal Disorders.” Ophthalmology. Manuscript no. 2014-736. Published online September 10, 2014. Accessed September 12, 2014. http://www.aaojournal.org/article/S0161-6420%2814%2900678-2/abstract

 

 

By Brooke Strickland

Researchers wanted to assess the usefulness of tuberculosis (TB) screening when diagnosing ocular TB in people that have uveitis. The study took place in a government-funded hospital (Los Angeles County Hospital). To gather the information, researchers examined the records of 142 patients that were seen between August 2011 and July 2012. They looked for manifestation/laterality of uveitis, purified protein derivative (PPD) test results, interferon γ release assay, chest x-ray, birthplace, treatment history and diagnosis. They indicated that ‘presumed TB-uveitis’ was diagnosed when individuals has positive TB screening and a positive response to anti-TB therapy, as well as clearly indicated ocular TB when Mycobacterium tuberculosis’ presence was demonstrated.

TB was found in 21.1% of the patients. There were six patients that were diagnosed with TB-related uveitis: one definite, four presumed, and one systemic TB with uveitis. With regard to PPD positivity, being foreign-born was the only statistically significant factor with OR of 2.26 (95% CI 1.01 to 5.13) if born in Mexico and 4.90 (95% CI 1.74 to 13.83) if born in other foreign countries. The post-test probabilities of a positive PPD in a uveitis patient showed a 17.2% (overall) or 30.3% (foreign-born patients) chance of ocular TB. (1)

What to take away from the study: Purified protein derivative skin tests are important when it comes to identifying TB-associated uveitis. This is especially the case for higher-risk groups such as immigrants or those from regions of the world where tuberculosis is prevalent.

1. Hong, Bryan Kun, Khanamiri, Hossein Nazari, Bababeygy, Simon, R., Rao, Narsing, A. “The utility of routine tuberculosis screening in county hospital patients with uveitis.” British Journal of Ophthalmology. 2014;98:1091-1095 doi:10.1136/bjophthalmol-2013-303937. Published online January 31, 2014. Accessed September 5, 2014. http://bjo.bmj.com/content/98/8/1091.abstract

 

 

By Brooke Strickland

In this retrospective case series, researchers wanted to define the patterns of hydroxychloroquine retinopathy distinct from the classic parafoveal maculopathy. The participants were gathered from two places: a small university referral practice and a large, multi-provider group practice. The patients had all been diagnosed with hydroxychloroquine retinopathy and those that had widespread or end-stage retinopathy were not included in the study. In total, there were 201 patients included, with 18% of these named as individuals of Asian descent.

Researchers initially reviewed ophthalmic studies and classified the retinopathy into three patterns: parafoveal (retinal changes 2°–6° from the fovea), pericentral (retinal changes ≥8° from the fovea), or mixed (retinal changes in both parafoveal and pericentral areas).

The results showed that 76% of the patients examined had typical parafoveal changes and 24% also showed a zone of pericentral damage. In addition, 12% showed no parafoveal damage, even though they had been diagnosed with pericentral retinopathy. Pericentral retinopathy was noticed in 50% of Asian patients but only 2% of white patients had it. The patients that had the pericentral pattern took hydroxychloroquine for a longer duration (19.5 years vs. 15 years) when compared to individuals with parafoveal pattern. They also required larger dose amounts (2186 vs. 1813g). However, it was noted that those patients had been diagnosed at a severe stage of toxicity. (1)

What to take away from the study: For those that have parafoveal patterns, hydroxychloroquine retinopathy doesn’t always occur. However, a pericentral pattern of damage is more common for Asian patients. For eye specialists to better recognize and diagnose pericentral and parafoveal hydroxychloroquine retinopathy, screening practices may need to be adjusted.

1. Melles, Ronald, MD, Marmor, Michael, F., MD. “Pericentral Retinopathy and Racial Differences in Hydroxychloroquine Toxicity.” Ophthalmology. Manuscript no. 2014-886. Published online August 30, 2014. Accessed September 5, 2014. http://www.aaojournal.org/article/S0161-6420%2814%2900622-8/abstract

 

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