Publications by authors named "Emily J Patterson"

14 Publications

  • Page 1 of 1

Retinal alterations in patients with Lafora disease.

Am J Ophthalmol Case Rep 2021 Sep 15;23:101146. Epub 2021 Jun 15.

Division of Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, USA.

Purpose: Lafora disease is a genetic neurodegenerative metabolic disorder caused by insoluble polyglucosan aggregate accumulation throughout the central nervous system and body. The retina is an accessible neural tissue, which may offer alternative methods to assess neurological diseases quickly and noninvasively. In this way, noninvasive imaging may provide a means to characterize neurodegenerative disease, which enables earlier identification and diagnosis of disease and the ability to monitor disease progression. In this study, we sought to characterize the retina of individuals with Lafora disease using non-invasive retinal imaging.

Methods: One eye of three individuals with genetically confirmed Lafora disease were imaged with optical coherence tomography (OCT) and adaptive optics scanning light ophthalmoscopy (AOSLO). When possible, OCT volume and line scans were acquired to assess total retinal thickness, ganglion cell-inner plexiform layer thickness, and outer nuclear layer + Henle fiber layer thickness. OCT angiography (OCTA) scans were acquired in one subject at the macula and optic nerve head (ONH). AOSLO was used to characterize the photoreceptor mosaic and examine the retinal nerve fiber layer (RNFL).

Results: Two subjects with previous seizure activity demonstrated reduced retinal thickness, while one subject with no apparent symptoms had normal retinal thickness. All other clinical measures, as well as parafoveal cone density, were within normal range. Nummular reflectivity at the level of the RNFL was observed using AOSLO in the macula and near the ONH in all three subjects.

Conclusions: This multimodal retinal imaging approach allowed us to observe a number of retinal structural features in all three individuals. Most notably, AOSLO revealed nummular reflectivity within the inner retina of each subject. This phenotype has not been reported previously and may represent a characteristic change produced by the neurodegenerative process.
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http://dx.doi.org/10.1016/j.ajoc.2021.101146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8239732PMC
September 2021

Optical Coherence Tomography Artifacts Are Associated With Adaptive Optics Scanning Light Ophthalmoscopy Success in Achromatopsia.

Transl Vis Sci Technol 2021 01 7;10(1):11. Epub 2021 Jan 7.

Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA.

Purpose: To determine whether artifacts in optical coherence tomography (OCT) images are associated with the success or failure of adaptive optics scanning light ophthalmoscopy (AOSLO) imaging in subjects with achromatopsia (ACHM).

Methods: Previously acquired OCT and non-confocal, split-detector AOSLO images from one eye of 66 subjects with genetically confirmed achromatopsia (15 and 51 ) were reviewed along with best-corrected visual acuity (BCVA) and axial length. OCT artifacts in interpolated vertical volumes from CIRRUS macular cubes were divided into four categories: (1) none or minimal, (2) clear and low frequency, (3) low amplitude and high frequency, and (4) high amplitude and high frequency. Each vertical volume was assessed once by two observers. AOSLO success was defined as sufficient image quality in split-detector images at the fovea to assess cone quantity.

Results: There was excellent agreement between the two observers for assessing OCT artifact severity category (weighted kappa = 0.88). Overall, AOSLO success was 47%. For subjects with OCT artifact severity category 1, AOSLO success was 65%; for category 2, 47%; for category 3, 11%; and for category 4, 0%. There was a significant association between OCT artifact severity category and AOSLO success ( = 0.0002). Neither BCVA nor axial length was associated with AOSLO success ( = 0.07 and = 0.75, respectively).

Conclusions: Artifacts in OCT volumes are associated with AOSLO success in ACHM. Subjects with less severe OCT artifacts are more likely to be good candidates for AOSLO imaging, whereas AOSLO was successful in only 7% of subjects with category 3 or 4 OCT artifacts. These results may be useful in guiding patient selection for AOSLO imaging.

Translational Relevance: Using OCT to prescreen patients could be a valuable tool for clinical trials that utilize AOSLO to reduce costs and decrease patient testing burden.
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http://dx.doi.org/10.1167/tvst.10.1.11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7804582PMC
January 2021

Intraobserver Repeatability and Interobserver Reproducibility of Foveal Cone Density Measurements in and -Associated Achromatopsia.

Transl Vis Sci Technol 2020 06 26;9(7):37. Epub 2020 Jun 26.

Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA.

Purpose: To examine repeatability and reproducibility of foveal cone density measurements in patients with and -associated achromatopsia (ACHM) using split-detection adaptive optics scanning light ophthalmoscopy (AOSLO).

Methods: Thirty foveae from molecularly confirmed subjects with ACHM, half of whom harbored disease-causing variants in and half in underwent nonconfocal split-detection AOSLO imaging. Cone photoreceptors within the manually delineated rod-free zone were manually identified twice by two independent observers. The coordinates of the marked cones were used for quantifying foveal cone density. Cone density and difference maps were generated to compare cone topography between trials.

Results: We observed excellent intraobserver repeatability in foveal cone density estimates, with intraclass correlation coefficients (ICCs) ranging from 0.963 to 0.991 for and subjects. Interobserver reproducibility was also excellent for both (ICC = 0.952; 95% confidence interval [CI], 0.903-1.0) and (ICC = 0.968; 95% CI, 0.935-1.0). However, Bland-Altman analysis revealed bias between observers.

Conclusions: Foveal cone density can be measured using the described method with good repeatability and reproducibility both for - and -associated ACHM. Any degree of bias observed among the observers is of uncertain clinical significance but should be evaluated on a study-specific basis.

Translational Relevance: This approach could be used to explore disease natural history, as well as to facilitate stratification of patients and monitor efficacy of interventions for ongoing and upcoming ACHM gene therapy trials.
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http://dx.doi.org/10.1167/tvst.9.7.37DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7414701PMC
June 2020

Interocular Symmetry of Foveal Cone Topography in Congenital Achromatopsia.

Curr Eye Res 2020 10 13;45(10):1257-1264. Epub 2020 Mar 13.

Ophthalmology & Visual Sciences, Medical College of Wisconsin , Milwaukee, Wisconsin, USA.

: To determine the interocular symmetry of foveal cone topography in achromatopsia (ACHM) using non-confocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO). : Split-detector AOSLO images of the foveal cone mosaic were acquired from both eyes of 26 subjects (mean age 24.3 years; range 8-44 years, 14 females) with genetically confirmed - or -associated ACHM. Cones were identified within a manually delineated rod-free zone. Peak cone density (PCD) was determined using an 80 × 80 μm sampling window within the rod-free zone. The mean and standard deviation (SD) of inter-cell distance (ICD) were calculated to derive the coefficient of variation (CV). Cone density difference maps were generated to compare cone topography between eyes. : PCD (mean ± SD) was 17,530 ± 9,614 cones/mm and 17,638 ± 9,753 cones/mm for right and left eyes, respectively ( = .677, Wilcoxon test). The mean (± SD) for ICD was 9.05 ± 2.55 µm and 9.24 ± 2.55 µm for right and left eyes, respectively ( = .410, paired -test). The mean (± SD) for CV of ICD was 0.16 ± 0.03 µm and 0.16 ± 0.04 µm for right and left eyes, respectively ( = .562, paired -test). Cone density maps demonstrated that cone topography of the ACHM fovea is non-uniform with local variations in cone density between eyes. : These results demonstrate the interocular symmetry of the foveal cone mosaic (both density and packing) in ACHM. As cone topography can differ between eyes of a subject, PCD does not completely describe the foveal cone mosaic in ACHM. Nonetheless, these findings are of value in longitudinal monitoring of patients during treatment trials and further suggest that both eyes of a given subject may have similar therapeutic potential and non-study eye can be used as a control.
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http://dx.doi.org/10.1080/02713683.2020.1737138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7487033PMC
October 2020

Assessing the Interocular Symmetry of Foveal Outer Nuclear Layer Thickness in Achromatopsia.

Transl Vis Sci Technol 2019 Sep 2;8(5):21. Epub 2019 Oct 2.

Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA.

Purpose: We examine the interocular symmetry of foveal outer nuclear layer (ONL) thickness measurements in subjects with achromatopsia (ACHM).

Methods: Images from 76 subjects with - or -associated ACHM and 42 control subjects were included in the study. Line or volume scans through the fovea of each eye were acquired using optical coherence tomography (OCT). Image quality was assessed for each image included in the analysis using a previously-described maximum tissue contrast index (mTCI) metric. Three foveal ONL thickness measurements were made by a single observer and interocular symmetry was assessed using the average of the three measurements for each eye.

Results: Mean (± standard deviation) foveal ONL thickness for subjects with ACHM was 79.7 ± 18.3 μm (right eye) and 79.2 ± 18.7 μm (left eye) compared to 112.9 ± 15.2 (right eye) and 112.1 ± 13.9 μm (left eye) for controls. Foveal ONL thickness did not differ between eyes for ACHM ( = 0.636) or control subjects ( = 0.434). No significant relationship between mTCI and observer repeatability was observed for either control ( = 0.140) or ACHM ( = 0.351) images.

Conclusions: While foveal ONL thickness is reduced in ACHM compared to controls, the high interocular symmetry indicates that contralateral ONL measurements could be used as a negative control in early-phase monocular treatment trials.

Translational Relevance: Foveal ONL thickness can be measured using OCT images over a wide range of image quality. The interocular symmetry of foveal ONL thickness in ACHM and control populations supports the use of the non-study eye as a control for clinical trial purposes.
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http://dx.doi.org/10.1167/tvst.8.5.21DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6779097PMC
September 2019

RAC-CNN: multimodal deep learning based automatic detection and classification of rod and cone photoreceptors in adaptive optics scanning light ophthalmoscope images.

Biomed Opt Express 2019 Aug 8;10(8):3815-3832. Epub 2019 Jul 8.

Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.

Quantification of the human rod and cone photoreceptor mosaic in adaptive optics scanning light ophthalmoscope (AOSLO) images is useful for the study of various retinal pathologies. Subjective and time-consuming manual grading has remained the gold standard for evaluating these images, with no well validated automatic methods for detecting individual rods having been developed. We present a novel deep learning based automatic method, called the rod and cone CNN (RAC-CNN), for detecting and classifying rods and cones in multimodal AOSLO images. We test our method on images from healthy subjects as well as subjects with achromatopsia over a range of retinal eccentricities. We show that our method is on par with human grading for detecting rods and cones.
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http://dx.doi.org/10.1364/BOE.10.003815DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6701534PMC
August 2019

Characterization of Retinal Structure in ATF6-Associated Achromatopsia.

Invest Ophthalmol Vis Sci 2019 06;60(7):2631-2640

Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States.

Purpose: Mutations in six genes have been associated with achromatopsia (ACHM): CNGA3, CNGB3, PDE6H, PDE6C, GNAT2, and ATF6. ATF6 is the most recent gene to be identified, though thorough phenotyping of this genetic subtype is lacking. Here, we sought to test the hypothesis that ATF6-associated ACHM is a structurally distinct form of congenital ACHM.

Methods: Seven genetically confirmed subjects from five nonconsanguineous families were recruited. Foveal hypoplasia and the integrity of the ellipsoid zone (EZ) band (a.k.a., IS/OS) were graded from optical coherence tomography (OCT) images. Images of the photoreceptor mosaic were acquired using confocal and nonconfocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO). Parafoveal cone and rod density values were calculated and compared to published normative data as well as data from two subjects harboring CNGA3 or CNGB3 mutations who were recruited for comparative purposes. Additionally, nonconfocal dark-field AOSLO images of the retinal pigment epithelium were obtained, with quantitative analysis performed in one subject with ATF6-ACHM.

Results: Foveal hypoplasia was observed in all subjects with ATF6 mutations. Absence of the EZ band within the foveal region (grade 3) or appearance of a hyporeflective zone (grade 4) was seen in all subjects with ATF6 using OCT. There was no evidence of remnant foveal cone structure using confocal AOSLO, although sporadic cone-like structures were seen in nonconfocal split-detection AOSLO. There was a lack of cone structure in the parafovea, in direct contrast to previous reports.

Conclusions: Our data demonstrate a near absence of cone structure in subjects harboring ATF6 mutations. This implicates ATF6 as having a major role in cone development and suggests that at least a subset of subjects with ATF6-ACHM have markedly fewer cellular targets for cone-directed gene therapies than do subjects with CNGA3- or CNGB3-ACHM.
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http://dx.doi.org/10.1167/iovs.19-27047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6594318PMC
June 2019

Deep learning based detection of cone photoreceptors with multimodal adaptive optics scanning light ophthalmoscope images of achromatopsia.

Biomed Opt Express 2018 Aug 18;9(8):3740-3756. Epub 2018 Jul 18.

Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.

Fast and reliable quantification of cone photoreceptors is a bottleneck in the clinical utilization of adaptive optics scanning light ophthalmoscope (AOSLO) systems for the study, diagnosis, and prognosis of retinal diseases. To-date, manual grading has been the sole reliable source of AOSLO quantification, as no automatic method has been reliably utilized for cone detection in real-world low-quality images of diseased retina. We present a novel deep learning based approach that combines information from both the confocal and non-confocal split detector AOSLO modalities to detect cones in subjects with achromatopsia. Our dual-mode deep learning based approach outperforms the state-of-the-art automated techniques and is on a par with human grading.
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http://dx.doi.org/10.1364/BOE.9.003740DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191607PMC
August 2018

Residual Cone Structure in Patients With X-Linked Cone Opsin Mutations.

Invest Ophthalmol Vis Sci 2018 08;59(10):4238-4248

University College London Institute of Ophthalmology, London, United Kingdom.

Purpose: To assess residual cone structure in subjects with mutations in exon 2, 3, and 4 of the OPN1LW or OPN1MW opsin.

Methods: Thirteen males had their OPN1LW/OPN1MW opsin genes characterized. The cone mosaic was imaged using both confocal and nonconfocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO), and retinal thickness was evaluated using optical coherence tomography (OCT). Six subjects completed serial imaging over a maximum period of 18 months and cone density was measured across imaging sessions.

Results: Ten subjects had an OPN1LW/OPN1MW "interchange" opsin mutation designated as LIAVA or LVAVA, which both introduce exon 3 splicing defects leading to a lack of functional photopigment in cones expressing LIAVA and greatly reduced functional photopigment in cones expressing LVAVA. Despite disrupted cone reflectivity and reduced numerosity, residual inner segments could be visualized. Similar patterns were observed in individuals with an exon 2 insertion, or an exon 4 splice defect, both of which are also expected to produce cones that are devoid of functional opsin protein. OCT revealed variably reduced retinal thickness. A significant inverse relationship was found between the proportion of waveguiding cones and axial length.

Conclusions: Split-detection imaging revealed that the altered appearance of the cone mosaic in confocal images for subjects with exon 2, 3, and 4 mutations was generally due to disrupted waveguiding, rather than structural loss, making them possible candidates for gene therapy to restore cone function. The relative fraction of waveguiding cones was highly variable across subjects, which appears to influence emmetropization in these subjects.
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http://dx.doi.org/10.1167/iovs.18-24699DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6103386PMC
August 2018

Adaptive optics imaging of inherited retinal diseases.

Br J Ophthalmol 2018 08 15;102(8):1028-1035. Epub 2017 Nov 15.

UCL Institute of Ophthalmology, University College London, London, UK.

Adaptive optics (AO) ophthalmoscopy allows for non-invasive retinal phenotyping on a microscopic scale, thereby helping to improve our understanding of retinal diseases. An increasing number of natural history studies and ongoing/planned interventional clinical trials exploit AO ophthalmoscopy both for participant selection, stratification and monitoring treatment safety and efficacy. In this review, we briefly discuss the evolution of AO ophthalmoscopy, recent developments and its application to a broad range of inherited retinal diseases, including Stargardt disease, retinitis pigmentosa and achromatopsia. Finally, we describe the impact of this microscopic imaging on our understanding of disease pathogenesis, clinical trial design and outcome metrics, while recognising the limitation of the small cohorts reported to date.
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http://dx.doi.org/10.1136/bjophthalmol-2017-311328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6059037PMC
August 2018

REPEATABILITY AND LONGITUDINAL ASSESSMENT OF FOVEAL CONE STRUCTURE IN CNGB3-ASSOCIATED ACHROMATOPSIA.

Retina 2017 Oct;37(10):1956-1966

*Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin; †Casey Eye Institute, Oregon Health & Science University, Portland, Oregon; ‡Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin; §Alexandria Faculty of Medicine, University of Alexandria, Alexandria, Egypt; ¶Pangere Center for Inherited Retinal Diseases, The Chicago Lighthouse, Chicago, Illinois; **Vitreo Retinal Associates, Gainesville, Florida; ††Bascom Palmer Eye Institute, University of Miami, Miami, Florida; ‡‡Applied Genetics Technologies Corporation (AGTC), Alachua, Florida; §§Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin; and ¶¶Department of Ophthalmology, University of Florida, Gainesville, Florida.

Purpose: Congenital achromatopsia is an autosomal recessive disease causing substantial reduction or complete absence of cone function. Although believed to be a relatively stationary disorder, questions remain regarding the stability of cone structure over time. In this study, the authors sought to assess the repeatability of and examine longitudinal changes in measurements of central cone structure in patients with achromatopsia.

Methods: Forty-one subjects with CNGB3-associated achromatopsia were imaged over a period of between 6 and 26 months using optical coherence tomography and adaptive optics scanning light ophthalmoscopy. Outer nuclear layer (ONL) thickness, ellipsoid zone (EZ) disruption, and peak foveal cone density were assessed.

Results: ONL thickness increased slightly compared with baseline (0.184 μm/month, P = 0.02). The EZ grade remained unchanged for 34/41 subjects. Peak foveal cone density did not significantly change over time (mean change 1% per 6 months, P = 0.126).

Conclusion: Foveal cone structure showed little or no change in this group of subjects with CNGB3-associated achromatopsia. Over the time scales investigated (6-26 months), achromatopsia seems to be a structurally stable condition, although longer-term follow-up is needed. These data will be useful in assessing foveal cone structure after therapeutic intervention.
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http://dx.doi.org/10.1097/IAE.0000000000001434DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537050PMC
October 2017

Residual Foveal Cone Structure in CNGB3-Associated Achromatopsia.

Invest Ophthalmol Vis Sci 2016 08;57(10):3984-95

Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States 2Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States 9Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, Un.

Purpose: Congenital achromatopsia (ACHM) is an autosomal recessive disorder in which cone function is absent or severely reduced. Gene therapy in animal models of ACHM have shown restoration of cone function, though translation of these results to humans relies, in part, on the presence of viable cone photoreceptors at the time of treatment. Here, we characterized residual cone structure in subjects with CNGB3-associated ACHM.

Methods: High-resolution imaging (optical coherence tomography [OCT] and adaptive optics scanning light ophthalmoscopy [AOSLO]) was performed in 51 subjects with CNGB3-associated ACHM. Peak cone density and inter-cone spacing at the fovea was measured using split-detection AOSLO. Foveal outer nuclear layer thickness was measured in OCT images, and the integrity of the photoreceptor layer was assessed using a previously published OCT grading scheme.

Results: Analyzable images of the foveal cones were obtained in 26 of 51 subjects, with nystagmus representing the major obstacle to obtaining high-quality images. Peak foveal cone density ranged from 7,273 to 53,554 cones/mm2, significantly lower than normal (range, 84,733-234,391 cones/mm2), with the remnant cones being either contiguously or sparsely arranged. Peak cone density was correlated with OCT integrity grade; however, there was overlap of the density ranges between OCT grades.

Conclusions: The degree of residual foveal cone structure varies greatly among subjects with CNGB3-associated ACHM. Such measurements may be useful in estimating the therapeutic potential of a given retina, providing affected individuals and physicians with valuable information to more accurately assess the risk-benefit ratio as they consider enrolling in experimental gene therapy trials. (www.clinicaltrials.gov, NCT01846052.).
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http://dx.doi.org/10.1167/iovs.16-19313DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4978151PMC
August 2016

Cone Photoreceptor Structure in Patients With X-Linked Cone Dysfunction and Red-Green Color Vision Deficiency.

Invest Ophthalmol Vis Sci 2016 07;57(8):3853-63

Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States 9Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States 10Department of Cell Biology, Neurobiology, & Anatomy, Medical Coll.

Purpose: Mutations in the coding sequence of the L and M opsin genes are often associated with X-linked cone dysfunction (such as Bornholm Eye Disease, BED), though the exact color vision phenotype associated with these disorders is variable. We examined individuals with L/M opsin gene mutations to clarify the link between color vision deficiency and cone dysfunction.

Methods: We recruited 17 males for imaging. The thickness and integrity of the photoreceptor layers were evaluated using spectral-domain optical coherence tomography. Cone density was measured using high-resolution images of the cone mosaic obtained with adaptive optics scanning light ophthalmoscopy. The L/M opsin gene array was characterized in 16 subjects, including at least one subject from each family.

Results: There were six subjects with the LVAVA haplotype encoded by exon 3, seven with LIAVA, two with the Cys203Arg mutation encoded by exon 4, and two with a novel insertion in exon 2. Foveal cone structure and retinal thickness was disrupted to a variable degree, even among related individuals with the same L/M array.

Conclusions: Our findings provide a direct link between disruption of the cone mosaic and L/M opsin variants. We hypothesize that, in addition to large phenotypic differences between different L/M opsin variants, the ratio of expression of first versus downstream genes in the L/M array contributes to phenotypic diversity. While the L/M opsin mutations underlie the cone dysfunction in all of the subjects tested, the color vision defect can be caused either by the same mutation or a gene rearrangement at the same locus.
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http://dx.doi.org/10.1167/iovs.16-19608DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4968428PMC
July 2016

Understanding disability glare: light scatter and retinal illuminance as predictors of sensitivity to contrast.

J Opt Soc Am A Opt Image Sci Vis 2015 Apr;32(4):576-85

The presence of a bright light in the visual field has two main effects on the retinal image: reduced contrast and increased retinal illuminance because of scattered light; the latter can, under some conditions, lead to an improvement in retinal sensitivity. The combined effect remains poorly understood, particularly at low light levels. A psychophysical flicker-cancellation test was used to measure the amount and angular distribution of scattered light in the eye for 40 observers. Contrast thresholds were measured using a functional contrast sensitivity test. Pupil-plane glare-source illuminances (i.e., 0, 1.35, and 19.21  lm/m2), eccentricities (5°, 10°, and 15°), and background luminances (1, 2.6, and 26  cd/m2) were investigated. Visual performance was better than predicted, based on a loss of retinal image contrast caused by scattered light, particularly in the mesopic range. Prediction accuracy improved significantly when the expected increase in retinal sensitivity in the presence of scattered light was also incorporated in the model.
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http://dx.doi.org/10.1364/JOSAA.32.000576DOI Listing
April 2015
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