Martin Gliem1, Philipp L Müller2, Johannes Birtel3, Philipp Herrmann3, Myra B McGuinness4, Frank G Holz3, Peter Charbel Issa5. 1. Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, and Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Ophthalmology, University Hospital of Bonn, Bonn, Germany; Centre for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany. 2. Department of Ophthalmology, University Hospital of Bonn, Bonn, Germany; Centre for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany; Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom. 3. Department of Ophthalmology, University Hospital of Bonn, Bonn, Germany; Centre for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany. 4. Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia. 5. Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, and Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom. Electronic address: study-enquiry@outlook.com.
Abstract
PURPOSE: To investigate quantitatively lipofuscin-associated fundus autofluorescence in patients with macular and cone/cone-rod dystrophies (MD/CCRDs). DESIGN: Prospective, single-center, case-control study. PARTICIPANTS: Two hundred thirty patients with MD/CCRDs who had undergone genetic testing and 110 control participants without any eye disease. METHODS: Participants were examined using quantitative fundus autofluorescence (qAF) imaging with a modified confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference (modified Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). Mean qAF values were obtained by averaging measurements from an 8-segment ring centered on the fovea (qAF8) and compared with controls. MAIN OUTCOME MEASURES: The qAF8 levels. RESULTS: Elevated qAF8 values were a frequent finding (n = 105 [45%]) and associated with ABCA4 (n = 73 [70%]), PRPH2 (n = 9 [9%]), CERKL (n = 3 [3%]), PROM1 (n = 2 [2%]), CRX (n = 1 [1%]), and CDHR1 (n = 1 [1%]) mutations. Reduced qAF8 values were rare (n = 15 [7%]) and found predominantly among patients with MERTK (n = 3 [20%]) and RDH5 (n = 2 [13%]) mutations. Patients with normal qAF8 values (n = 110 [48%]) showed high genotypic heterogeneity. For various genes including ABCA4, PRPH2, CDHR1, and PROM1, higher qAF8 measures were associated with specific phenotypes and genotypes. For instance, qAF8 values were normal in PRPH2-related central areolar chorioretinal dystrophy but increased in PRPH2-related Stargardt-like retinopathy. Accordingly, high qAF8 levels were associated with specific genetic causes and mutation detection rates in characteristic but genetically heterogenous clinical phenotypes, such as a Stargardt-like flecked fundus, bull's eye maculopathy, or pattern dystrophy. In genetically unsolved cases (16 with elevated, 35 with normal, 7 with reduced qAF values), qAF8 was used to support or reject ambiguous results of genetic testing, to suggest underlying pathogenic pathways, and to predict disease in otherwise healthy participants. CONCLUSIONS: Quantitative fundus autofluorescence imaging revealed characteristic qAF levels in association with certain gene mutations and in participants without detected mutations. These findings indicate that qAF may facilitate differential diagnostics of MD/CCRDs and may offer novel pathogenetic insights that may be of particular value for the assessment of future treatment approaches.
PURPOSE: To investigate quantitatively lipofuscin-associated fundus autofluorescence in patients with macular and cone/cone-rod dystrophies (MD/CCRDs). DESIGN: Prospective, single-center, case-control study. PARTICIPANTS: Two hundred thirty patients with MD/CCRDs who had undergone genetic testing and 110 control participants without any eye disease. METHODS:Participants were examined using quantitative fundus autofluorescence (qAF) imaging with a modified confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference (modified Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). Mean qAF values were obtained by averaging measurements from an 8-segment ring centered on the fovea (qAF8) and compared with controls. MAIN OUTCOME MEASURES: The qAF8 levels. RESULTS: Elevated qAF8 values were a frequent finding (n = 105 [45%]) and associated with ABCA4 (n = 73 [70%]), PRPH2 (n = 9 [9%]), CERKL (n = 3 [3%]), PROM1 (n = 2 [2%]), CRX (n = 1 [1%]), and CDHR1 (n = 1 [1%]) mutations. Reduced qAF8 values were rare (n = 15 [7%]) and found predominantly among patients with MERTK (n = 3 [20%]) and RDH5 (n = 2 [13%]) mutations. Patients with normal qAF8 values (n = 110 [48%]) showed high genotypic heterogeneity. For various genes including ABCA4, PRPH2, CDHR1, and PROM1, higher qAF8 measures were associated with specific phenotypes and genotypes. For instance, qAF8 values were normal in PRPH2-related central areolar chorioretinal dystrophy but increased in PRPH2-related Stargardt-like retinopathy. Accordingly, high qAF8 levels were associated with specific genetic causes and mutation detection rates in characteristic but genetically heterogenous clinical phenotypes, such as a Stargardt-like flecked fundus, bull's eye maculopathy, or pattern dystrophy. In genetically unsolved cases (16 with elevated, 35 with normal, 7 with reduced qAF values), qAF8 was used to support or reject ambiguous results of genetic testing, to suggest underlying pathogenic pathways, and to predict disease in otherwise healthy participants. CONCLUSIONS: Quantitative fundus autofluorescence imaging revealed characteristic qAF levels in association with certain gene mutations and in participants without detected mutations. These findings indicate that qAF may facilitate differential diagnostics of MD/CCRDs and may offer novel pathogenetic insights that may be of particular value for the assessment of future treatment approaches.
Authors: Andreas Berlin; Mark E Clark; Thomas A Swain; Nathan A Fischer; Gerald McGwin; Kenneth R Sloan; Cynthia Owsley; Christine A Curcio Journal: Transl Vis Sci Technol Date: 2022-10-03 Impact factor: 3.048
Authors: Virginie M M Buhler; Lieselotte Berger; André Schaller; Martin S Zinkernagel; Sebastian Wolf; Pascal Escher Journal: Genes (Basel) Date: 2021-05-26 Impact factor: 4.096