Purpose:To perform low cost fixation stability assessment and kinetic perimetry during live fundu... more Purpose:To perform low cost fixation stability assessment and kinetic perimetry during live fundus viewing using the Digital Light Ophthalmoscope (DLO). Methods:Kinetic perimetry was performed on 12 undilated normal subjects aged 25 - 63 with real-time confocal retinal imaging using the DLO. Having similar functionality to a Scanning Laser Ophthalmoscope, but at far lower cost, the DLO uses a single digital light projector to provide both the illumination for confocal imaging, and the stimuli for visual function measurements. Confocal retinal imaging is performed at 20 Hz with a 35.1 deg field of view. The imaging illumination is provided by a red 630 nm LED, with 40 µW time-averaged power at the cornea. Stimuli are shown in black over the red imaging illumination and are operator controlled in shape and position in real-time. The black stimuli are easily seen by the subject and are also clearly visible on the live view of the fundus. Subjects were instructed to stare at a fixation ...
Purpose-To develop a simplified device that performs fundus perimetry techniques, such as fixatio... more Purpose-To develop a simplified device that performs fundus perimetry techniques, such as fixation mapping and kinetic perimetry. Methods-We added visual stimulation to a near infrared retinal imager, the Laser Scanning Digital Camera (LSDC). This device uses slit scanning illumination combined with a 2 dimensional CMOS detector, with continuous viewing of the retina. The CMOS read-out was synchronized with the slit scanning, thereby serving as a confocal aperture to reduce stray light in retinal images. Series of retinal images of 36 deg were automatically aligned to provide data for fixation maps and quantification of fixation stability. The LSDC and alignment techniques also provided fundus viewing with retinal location correction for scotoma mapping. Results-First, fixation mapping was readily performed in patients with central scotoma or amblyopia. The automatic alignment algorithm allowed quantification of fixation stability in patients with macular pathologies that did not cause scotoma. Second, fixation stability was rapidly and quantitatively assessed by the automatic registration of a series of retina images. There was no significant difference in the fixation stability with automatic vs. manual alignment. Kinetic perimetry demonstrated that fundus imaging helped reduce the variability of perimetric data by identifying and preventing false positives due to eye motion. We found that the size of the blind spot was significantly larger for dark targets on brighter backgrounds than when the contrast was reversed (p < 0.045). This is consistent with incremental targets being detected partially or wholly due to scattered light falling on more sensitive retinal locations. Conclusions-Fundus perimetry with the LSDC allows for a wide range of fixation and perimetry tasks.
Optometry - Journal of the American Optometric Association, 2009
The goal of this survey study is to determine the low vision rehabilitation training practices of... more The goal of this survey study is to determine the low vision rehabilitation training practices of optometrists who prescribe near magnifying devices for low vision patients who have moderate visual impairment from age-related macular degeneration. METHODS: A total of 2,028 surveys were sent electronically or by mail. A total of 136 optometrists reporting a special interest in low vision rehabilitation responded to an 18-item survey about practice mode, educational background, affiliations, and other demographic information. They were queried on methodology, frequency, and specific strategic content of rehabilitation training. RESULTS: Sixty-eight percent of the 136 respondents were private practitioners. Fifty-four percent of all respondents agreed that they train patients for 1 hour or less. Nine percent provided 3 or more training visits and were more likely to utilize an occupational therapist. Forty-six percent of respondents reported using various other personnel to perform the training. The majority of respondents spend 25% of their time examining low vision patients. Eighteen percent of all respondents were low vision residency trained. CONCLUSIONS: Descriptions of current practice patterns are difficult to ascertain without consensus on terminology and management criteria among low vision practitioners. This survey and accompanying literature review support the need for clinical research and education that will establish an efficacious and cost-effective model for private outpatient low vision rehabilitation for individuals with various levels of vision impairment to determine the true availability of low vision rehabilitation care in the United States.
Purpose:To perform low cost fixation stability assessment and kinetic perimetry during live fundu... more Purpose:To perform low cost fixation stability assessment and kinetic perimetry during live fundus viewing using the Digital Light Ophthalmoscope (DLO). Methods:Kinetic perimetry was performed on 12 undilated normal subjects aged 25 - 63 with real-time confocal retinal imaging using the DLO. Having similar functionality to a Scanning Laser Ophthalmoscope, but at far lower cost, the DLO uses a single digital light projector to provide both the illumination for confocal imaging, and the stimuli for visual function measurements. Confocal retinal imaging is performed at 20 Hz with a 35.1 deg field of view. The imaging illumination is provided by a red 630 nm LED, with 40 µW time-averaged power at the cornea. Stimuli are shown in black over the red imaging illumination and are operator controlled in shape and position in real-time. The black stimuli are easily seen by the subject and are also clearly visible on the live view of the fundus. Subjects were instructed to stare at a fixation ...
Purpose-To develop a simplified device that performs fundus perimetry techniques, such as fixatio... more Purpose-To develop a simplified device that performs fundus perimetry techniques, such as fixation mapping and kinetic perimetry. Methods-We added visual stimulation to a near infrared retinal imager, the Laser Scanning Digital Camera (LSDC). This device uses slit scanning illumination combined with a 2 dimensional CMOS detector, with continuous viewing of the retina. The CMOS read-out was synchronized with the slit scanning, thereby serving as a confocal aperture to reduce stray light in retinal images. Series of retinal images of 36 deg were automatically aligned to provide data for fixation maps and quantification of fixation stability. The LSDC and alignment techniques also provided fundus viewing with retinal location correction for scotoma mapping. Results-First, fixation mapping was readily performed in patients with central scotoma or amblyopia. The automatic alignment algorithm allowed quantification of fixation stability in patients with macular pathologies that did not cause scotoma. Second, fixation stability was rapidly and quantitatively assessed by the automatic registration of a series of retina images. There was no significant difference in the fixation stability with automatic vs. manual alignment. Kinetic perimetry demonstrated that fundus imaging helped reduce the variability of perimetric data by identifying and preventing false positives due to eye motion. We found that the size of the blind spot was significantly larger for dark targets on brighter backgrounds than when the contrast was reversed (p < 0.045). This is consistent with incremental targets being detected partially or wholly due to scattered light falling on more sensitive retinal locations. Conclusions-Fundus perimetry with the LSDC allows for a wide range of fixation and perimetry tasks.
Optometry - Journal of the American Optometric Association, 2009
The goal of this survey study is to determine the low vision rehabilitation training practices of... more The goal of this survey study is to determine the low vision rehabilitation training practices of optometrists who prescribe near magnifying devices for low vision patients who have moderate visual impairment from age-related macular degeneration. METHODS: A total of 2,028 surveys were sent electronically or by mail. A total of 136 optometrists reporting a special interest in low vision rehabilitation responded to an 18-item survey about practice mode, educational background, affiliations, and other demographic information. They were queried on methodology, frequency, and specific strategic content of rehabilitation training. RESULTS: Sixty-eight percent of the 136 respondents were private practitioners. Fifty-four percent of all respondents agreed that they train patients for 1 hour or less. Nine percent provided 3 or more training visits and were more likely to utilize an occupational therapist. Forty-six percent of respondents reported using various other personnel to perform the training. The majority of respondents spend 25% of their time examining low vision patients. Eighteen percent of all respondents were low vision residency trained. CONCLUSIONS: Descriptions of current practice patterns are difficult to ascertain without consensus on terminology and management criteria among low vision practitioners. This survey and accompanying literature review support the need for clinical research and education that will establish an efficacious and cost-effective model for private outpatient low vision rehabilitation for individuals with various levels of vision impairment to determine the true availability of low vision rehabilitation care in the United States.
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Papers by Elli Kollbaum