Macular Degeneration: Friberg TR

Friberg TR. · No affiliation provided · Ophthalmic Surg Lasers. · Pubmed #10574490 No free full text.

This publication has no abstract.

Dafer RM, Schneck M, Friberg TR, Jay WM. · Department of Neurology, Loyola University Chicago, Stritch School of Medicine, Maywood, IL 60153, USA. · Semin Ophthalmol. · Pubmed #17763246 No free full text.

Abstract: Ranibizumab (Lucentis), a recombinant monoclonal antibody, blocks all active forms of vascular endothelial growth factor A and was the first treatment for age-related macular degeneration shown to improve visual acuity in a substantial percentage of patients rather than slowing visual loss. Bevacizumab (Avastin) has a similar action, is related to the ranibizumab compound with respect to its structure, but has not been approved by the FDA for intravitreal use and therefore must be utilized only in an off-label setting. While ranibizumab was approved by the FDA at a dose of 0.5 mg per intravitreal injection, the manufacturer recently issued a letter to physicians warning of the increased risk of stroke at the FDA-approved dose as compared to a lower studied dose of 0.3 mg. An interim analysis of the ongoing SAILOR study revealed a 1.2% risk of stroke in the 0.5 mg arm versus 0.3% in the 0.3 mg arm (p = 0.02). It is unclear whether the trend toward a higher risk of stroke in patients receiving 0.5 mg dose of ranibizumab would persist in the final analysis, but details such as causality, topography, and severity of stroke in the SAILOR study should also be delineated. The risks of intraocular use of bevacizumab remain largely unknown at this time.

Friberg TR. · Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA. · Semin Ophthalmol. · Pubmed #10790574 No free full text.

Abstract: Drusen are deposits located deep in the sensory retina that are seen characteristically in eyes with macular degeneration (AMD). As multiple large drusen are a risk factor for the development of visual loss from AMD, laser strategies to cause drusen to resorb have been devised. Two large, randomized controlled trials using laser photocoagulation prophylactically for the treatment of AMD are underway to determine the efficacy of such treatment.

Rodanant N, Friberg TR, Cheng L, Aurora A, Bartsch D, Toyoguchi M, Corbin PS, El-Bradey MH, Freeman WR. · Shiley Eye Center, University of California San Diego, La Jolla 92093, USA. · Am J Ophthalmol. · Pubmed #12383815 No free full text.

Abstract: PURPOSE: To determine the predictors of drusen reduction in eyes with nonexudative age-related macular degeneration (ARMD) treated with subthreshold infrared (810 nm) diode laser macular grid photocoagulation. Additionally, to determine the relationship of laser-induced drusen reduction and best-corrected visual acuity (BCVA) 18 months after laser treatment.DESIGN: Randomized controlled clinical trial.METHODS: Fifty patients (100 eyes) with bilateral nonexudative ARMD were enrolled at two centers. One eye of each patient was randomized to the observation; the other eye was treated with 48 subthreshold (invisible end point) applications of infrared (810 nm) diode laser in a macular grid pattern. The eyes that received subthreshold laser treatment were compared with the eyes that received no treatment. The baseline fundus characteristics (number, size, and distribution of drusen, as well as focal hyperpigmentation) from two macula areas (central 1500 micro diameter, pericentral 1500 micro ring area) on stereo color photographs, the number of laser-induced lesions, and the area of laser induced retinal pigment epithelial (RPE) lesions on fluorescein angiography 3 months after treatment were studied as predictors of major drusen reduction (> or = 50% drusen reduction from baseline) 18 months after laser treatment. BCVA at baseline and 18 months later was compared in observation eyes and in laser-treated eyes.RESULTS: Eighteen months after randomization, 24 (48%) of 50 eyes treated with subthreshold laser had major drusen reduction compared with three (6%) of 50 observation eyes (P =.00001). At 3 months post-treatment in laser-treated eyes with major drusen reduction, the mean number of laser-induced lesions on fluorescein angiography was 30.7 and the mean area of RPE change was 0.81 mm(2) compared with 14.8 laser-induced lesions and 0.35 mm(2) area of RPE change in eyes without major drusen reduction (P =.0001 and P =.0003, respectively). At baseline, fundus characteristics were not significantly different between observation eyes and laser-treated eyes or between the major drusen reduction group and the nonmajor drusen reduction group. At 18 months after treatment, BCVA was not significantly different in laser-treated eyes and in observation eyes.CONCLUSIONS: Subthreshold infrared (810 nm) diode laser macular grid photocoagulation in eyes with nonexudative ARMD significantly reduced drusen 18 months after laser treatment. Both the number of subthreshold laser lesions and the area of RPE changes visible on fluorescein angiography 3 months after treatment appeared to be predictors for major drusen reduction 18 months after treatment. However, it remains to be determined whether laser-induced drusen reduction is beneficial for visual acuity or reduces the incidence of choroidal neovascularization (CNV) in eyes with nonexudative ARMD.

Olk RJ, Friberg TR, Stickney KL, Akduman L, Wong KL, Chen MC, Levy MH, Garcia CA, Morse LS. · The Retina Center of St. Louis Co., Missouri 63141, USA. · Ophthalmology. · Pubmed #10571341 No free full text.

Abstract: OBJECTIVE: This pilot study collected preliminary information on the effectiveness and safety of infrared (810-nm) diode laser macular grid photocoagulation in patients with nonexudative age-related macular degeneration (AMD). Results from this pilot study were used in designing a larger, multicenter, randomized clinical trial. DESIGN: A multicenter, randomized, controlled, clinical trial. PARTICIPANTS: A total of 229 eyes of 152 patients with AMD were enrolled in the pilot study. Seventy-five patients with 1 eye eligible (75 eyes) were enrolled in the unilateral arm of the study; 77 patients with both eyes eligible (154 eyes) were enrolled in the bilateral arm of the study. In the unilateral study arm, 32 eyes were randomized to the observation group, 27 eyes were treated with visible endpoint burns, and 16 eyes were treated with invisible endpoint (subthreshold) lesions. In the bilateral study arm, 77 eyes were in the observation group, 36 eyes were treated with visible burns, and 41 eyes were treated with subthreshold (invisible) lesions. INTERVENTION: Eyes were treated with infrared (810-nm) diode laser macular grid photocoagulation using either visible burns or subthreshold (invisible) lesions and compared to eyes receiving no treatment. MAIN OUTCOME MEASURES: Reduction of drusen, change in visual acuity, and rate of choroidal neovascularization (CNV) membrane formation. RESULTS: At 12 months after treatment, 62% of eyes treated with visible burns had a clinically significant reduction in drusen, whereas this proportion (65%) was reached in 18 months for eyes treated with subthreshold lesions. At 24 months' follow-up, treated eyes had a significant reduction in drusen compared to observation eyes (P < 0.0001). Visual acuity was significantly improved in treated eyes at 12, 18, and 24 months compared to observation eyes (P < 0.001). Choroidal neovascularization formation was similar in treated and observation eyes through 24 months' follow-up. Complications included CNV associated with six eyes treated with visible burns and a juxtafoveal laser scar in one eye treated with visible burns. CONCLUSIONS: Infrared (810-nm) diode laser macular grid photocoagulation in patients with nonexudative AMD significantly reduces drusen levels (P < 0.0001) and significantly improves visual acuity (P < 0.001) when either visible endpoint burns or subthreshold endpoint lesions are used. Complications were fewer using subthreshold endpoint lesions. A larger, multicenter, prospective clinical trial with longer follow-up is needed to determine the efficacy of treatment in reducing the rate of CNV formation. Data from this clinical pilot study have been used to design the Prophylactic Treatment of AMD Trial (PTAMD), a multicenter, randomized, prospective clinical trial currently in progress comparing subthreshold (invisible) treatment to observation in eyes with nonexudative AMD.

Friberg TR, Rosenberg PR, Bonfioli A. · The Eye and Ear Institute, 203 Lothrop Street, Pittsburgh, PA 15213, USA. friberg+@pitt.edu · Semin Ophthalmol. · Pubmed #19241294 No free full text.

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Ishikawa H, Kim J, Friberg TR, Wollstein G, Kagemann L, Gabriele ML, Townsend KA, Sung KR, Duker JS, Fujimoto JG, Schuman JS. · Department of Ophthalmology, UPMC Eye Center, Eye and Ear Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA. · Invest Ophthalmol Vis Sci. · Pubmed #18952923 No free full text.

Abstract: PURPOSE: To develop a semiautomated method to visualize structures of interest (SoIs) along their contour within three-dimensional, spectral domain optical coherence tomography (3D SD-OCT) data, without the need for segmentation. METHODS: With the use of two SD-OCT devices, the authors obtained 3D SD-OCT data within 6 x 6 x 1.4-mm and 6 x 6 x 2-mm volumes, respectively, centered on the fovea in healthy eyes and in eyes with retinal pathology. C-mode images were generated by sampling a variable thickness plane semiautomatically modeled to fit the contour of the SoI. Unlike published and commercialized methods, this method did not require retinal layer segmentation, which is known to fail frequently in the presence of retinal pathology. Four SoIs were visualized for healthy eyes: striation of retinal nerve fiber (RNF), retinal capillary network (RCN), choroidal capillary network (CCN), and major choroidal vasculature (CV). Various SoIs were visualized for eyes with retinal pathology. RESULTS: Seven healthy eyes and seven eyes with retinal pathology (cystoid macular edema, central serous retinopathy, vitreoretinal traction, and age-related macular degeneration) were imaged. CCN and CV were successfully visualized in all eyes, whereas RNF and RCN were visualized in all healthy eyes and in 42.8% of eyes with pathologies. Various SoIs were successfully visualized in all eyes with retinal pathology. CONCLUSIONS: The proposed C-mode contour modeling may provide clinically useful images of SoIs even in eyes with severe pathologic changes in which segmentation algorithms fail.

Friberg TR, Huang L, Palaiou M, Bremer R. · UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA. · Ophthalmic Surg Lasers Imaging. · Pubmed #17396693 No free full text.

Abstract: BACKGROUND AND OBJECTIVE: The authors used a drusen detection algorithm to quantitate drusen on digitized images and determined its precision and accuracy. PATIENTS AND METHODS: Fundus images from 349 participants in the Age-Related Eye Disease Study trial were digitized and analyzed with the Drusen Analyzer (IRIDEX Corporation, Mountain View, CA). The size, number, and area of the drusen in two macular regions were computed by two readers using an interactive approach. Measurements were compared to data generated by reading center methods. RESULTS: For the Analyzer, inter-observer agreement was 0.79 (SE = 0.02) and 0.86 (SE = 0.01) (kappa statistic). Intra-observer precision was 0.835 and 0.880 (Spearman coefficients). Categorical agreement (weighted kappa) between the Analyzer and reading center results for the two regions was (0.76, 0.58) and (0.68, 0.68) for readers A and B. The time required to quantitate an image using the Analyzer was 105 +/- 52 and 218 +/- 102 seconds for the two regions, respectively. CONCLUSIONS: Quantitative detection of drusen can be performed reproducibly and efficiently. Comparisons to more labor intensive reading center techniques suggest that the results are similar but that the algorithm is more sensitive and precise.

Friberg TR, Musch DC, Lim JI, Morse L, Freeman W, Sinclair S, Anonymous00275. · Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA. · Ophthalmology. · Pubmed #16581422 No free full text.

Abstract: OBJECTIVE: To determine the effects of subthreshold 810-nm-diode laser treatment on the rate of development of choroidal neovascularization (primary end point) and the effect on visual acuity (VA) in participants with multiple large drusen in one eye and a preexisting neovascular age-related macular degeneration (AMD) lesion in the other. DESIGN: Multicenter, prospective, randomized controlled trial. PARTICIPANTS: Two hundred forty-four patients > or =50 years of age and with a neovascular or advanced AMD lesion in one eye and, in the fellow "study" eye, (1) at least 5 drusen > or = 63 mum in diameter, (2) Early Treatment Diabetic Retinopathy Study best-corrected VA (BCVA) of 20/63 or better, and (3) no evidence of neovascularization at baseline. METHODS: Patients were randomized to treatment or observation of their study eye at each of 22 centers. At each visit, the protocol specified that BCVA, a complete retinal examination, and fluorescein angiography be documented. Treated eyes had a grid of 48 extrafoveal, subthreshold diode (810 nm) laser spots, 125 mum in diameter, placed in an annulus outside of the foveola. Patients were seen at baseline and at 3, 6, 12, 18, 24, 30, and 36 months after randomization. No retreatments were allowed. MAIN OUTCOME MEASURES: Development of choroidal neovascularization (as confirmed by fluorescein angiography) and change in BCVA. RESULTS: Throughout follow-up, the rate of choroidal neovascularization events in treated eyes consistently exceeded that in observed eyes. At 1 year, the difference was 15.8% versus 1.4% (P = 0.05). Most of the intergroup differences in choroidal neovascularization events occurred during the first 2 years of follow-up. Treated eyes showed a higher rate of VA loss (> or =3 lines) at 3- and 6-month follow-ups relative to observed eyes (8.3% vs. 1% and 11.4% vs. 4%, respectively; Ps = 0.02, 0.07). After 6 months, no significant differences were observed in VA loss between groups. CONCLUSION: Prophylactic subthreshold 810-nm-diode laser treatment to an eye with multiple large drusen in a patient whose fellow eye has already suffered a neovascular event places the treated eye at higher risk of developing choroidal neovascularization. We advise against using prophylactic subthreshold diode laser treatment in these eyes.

Friberg TR, Pandya A, Nazari K. · Department of Ophthalmology, The Eye & Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 824, Pittsburgh, PA 15213, USA. · Semin Ophthalmol. · Pubmed #15491007 No free full text.

Abstract: PURPOSE: To review the results of transpupillary thermotherapy (TTT) on choroidal neovascular membranes associated with age-related macular degeneration (AMD). MATERIALS AND METHODS: 35 eyes of 35 patients with AMD and choroidal neovascularization and exudation were treated with TTT and had fundus photographs and fluorescein angiography (FA) before and at least six months after TTT. 28 eyes had predominantly occult lesions as seen on FA, while 7 demonstrated primarily classic lesions. All were treated with 650mw power or less using the 810 nm diode laser (3000 micron spot, duration of 60 seconds). Visual acuity, lesion size, and amount of subretinal fluid were determined by results of examination and review of photographs and fluorescein angiograms. RESULTS: A 50% reduction in subretinal fluid was achieved in 67% of treated eyes overall, with stabilization of vision (less than three lines of visual acuity lost) in 86%. Complications from treatment were infrequent (9%) and involved hemorrhage noted in the region of treatment upon follow-up. CONCLUSION: TTT promotes resolution of subretinal fluid and appears to stabilize visual acuity in patients with exudative AMD.

Mainster MA, Friberg TR. · Department of Ophthalmology, University of Kansas Medical Center, 3907 Rainbow Boulevard, Kansas City, KS 66160-7379, USA. · Semin Ophthalmol. · Pubmed #15491003 No free full text.

This publication has no abstract.

Friberg TR. · University of Pittsburgh, Eye & Ear Institute, 203 Lothrop Street, Room 824, Pittsburgh, PA 15213, USA. · Semin Ophthalmol. · Pubmed #15487694 No free full text.

Abstract: PURPOSE: To assess the effectiveness of subthreshold (invisible after placement) and threshold (barely visible after placement) 810nm laser photocoagulation in the treatment of clinically significant diabetic macular edema. METHODS: A grid of subthreshold laser spots was used to treat patients with diabetic edema. Retrospectively, the results of treatment of 20 eyes of 20 patients were compared to the results of treatment of 120 eyes of 120 patients using a grid of threshold laser lesions. RESULTS: At six months, 60% of subthreshold treated eyes and 75% of threshold treated eyes showed anatomic resolution of macular edema. Improvement or stabilization of visual acuity was achieved in 85% of threshold or subthreshold treated eyes. CONCLUSION: Gentle grid treatment of regions of diabetic macular edema was effective in ameliorating the edema and limiting visual loss. Subthreshold laser was less effective in promoting resolution of edema compared to threshold lesions, though the difference was not significant in this instance.

Friberg TR. · University of Pittsburgh School of Medicine, and the Eye and Ear Institute of Pittsburgh, PA, USA. · Ophthalmic Surg Lasers. · Pubmed #10929973 No free full text.

Abstract: BACKGROUND AND OBJECTIVE: Some patients with macular disease, because of physical infirmity or disability, cannot be treated with laser photocoagulation using a typical slit lamp delivery system. The purpose of this study was to determine whether the binocular indirect ophthalmoscope could be used to deliver treatment to the macula when photocoagulation would otherwise be very difficult, if not impossible, to perform. MATERIALS AND METHODS: Ten eyes of 10 patients who could not sit for slit lamp laser delivery were treated with binocular indirect ophthalmoscope laser photocoagulation over a 36 month period. Eight had subfoveal choroidal neovascularization (CNV) from age-related macular degeneration (AMD), and 2 patients had clinically significant macular edema (CSME) from diabetes mellitus. Argon laser photocoagulation was delivered to the choroidal neovascular membrane in patients with exudative AMD, and a grid treatment was given to eyes with diabetic macular edema. RESULTS: Six of 8 patients with exudative AMD were successfully treated with eradication of the CNV. Two required retreatment within 6 months of original treatment. Both patients with CSME had resolution of their edema at 3 and 6 months after treatment. Best corrected visual acuity did not change by more than 2 Snellen lines in any patient with CNV and 1 Snellen line in patients with CSME. No complications of treatment were encountered. CONCLUSION: In certain circumstances, laser photocoagulation of the macula using the indirect ophthalmoscope laser delivery system should be considered when more conventional treatment strategies cannot be implemented.

D'Amico DJ, Friberg TR. · No affiliation provided · Am J Ophthalmol. · Pubmed #11491094 No free full text.

This publication has no abstract.