AIM: To report novel spectral domain optical coherence tomography (SD-OCT) findings and new mutational data in patients with 'cone dystrophy with supernormal rod electroretinogram', a recessive childhood onset retinal dystrophy consequent upon mutation in the KCNV2 gene. DESIGN/ METHODS: This was a comparative case series study of 12 patients with clinical and/or electrophysiological findings in keeping with KCNV2 mutation. Clinical examination and electrophysiological testing results were reviewed. Fundus photography and autofluorescence imaging were performed. Retinal layer appearance and thickness were evaluated using SD-OCT. The coding region and intron-exon boundaries of KCNV2 were screened by direct sequencing. RESULTS: Mutations in KCNV2 were detected in all families; five of these changes were novel. Pattern electroretinograms were undetectable and full-field electroretinograms showed findings specific for the disorder. SD-OCT demonstrated bilateral morphological changes, usually confined to the fovea. Four foveal SD-OCT phenotypes were observed: (i) discontinuous inner and outer segment (IS/OS) junction reflectivity (6 patients), (ii) loss of IS/OS line and an optical gap in the foveola (2 patients); (iii) IS/OS junction disruption and profound foveal depth reduction, without optical gap and with preserved retinal pigment epithelium (RPE) complex (2 patients); and (iv) outer retina and RPE complex abnormalities (2 patients). Thinning of the neurosensory retina was observed in all eyes. CONCLUSION: In KCNV2 retinopathy foveal morphological changes are evident on SD-OCT even in the early stages of disease. However, there appears to be a window of opportunity, before marked structural damage has occurred, during which novel therapeutic intervention, such as gene replacement therapy, may rescue retinal function.
AIM: To report novel spectral domain optical coherence tomography (SD-OCT) findings and new mutational data in patients with 'cone dystrophy with supernormal rod electroretinogram', a recessive childhood onset retinal dystrophy consequent upon mutation in the KCNV2 gene. DESIGN/ METHODS: This was a comparative case series study of 12 patients with clinical and/or electrophysiological findings in keeping with KCNV2 mutation. Clinical examination and electrophysiological testing results were reviewed. Fundus photography and autofluorescence imaging were performed. Retinal layer appearance and thickness were evaluated using SD-OCT. The coding region and intron-exon boundaries of KCNV2 were screened by direct sequencing. RESULTS: Mutations in KCNV2 were detected in all families; five of these changes were novel. Pattern electroretinograms were undetectable and full-field electroretinograms showed findings specific for the disorder. SD-OCT demonstrated bilateral morphological changes, usually confined to the fovea. Four foveal SD-OCT phenotypes were observed: (i) discontinuous inner and outer segment (IS/OS) junction reflectivity (6 patients), (ii) loss of IS/OS line and an optical gap in the foveola (2 patients); (iii) IS/OS junction disruption and profound foveal depth reduction, without optical gap and with preserved retinal pigment epithelium (RPE) complex (2 patients); and (iv) outer retina and RPE complex abnormalities (2 patients). Thinning of the neurosensory retina was observed in all eyes. CONCLUSION: In KCNV2 retinopathy foveal morphological changes are evident on SD-OCT even in the early stages of disease. However, there appears to be a window of opportunity, before marked structural damage has occurred, during which novel therapeutic intervention, such as gene replacement therapy, may rescue retinal function.
Authors: Frederick T Collison; Jason C Park; Gerald A Fishman; Edwin M Stone; J Jason McAnany Journal: Doc Ophthalmol Date: 2019-03-29 Impact factor: 2.379
Authors: Katie E Smith; Susan E Wilkie; Joseph T Tebbs-Warner; Bradley J Jarvis; Linn Gallasch; Martin Stocker; David M Hunt Journal: J Biol Chem Date: 2012-10-31 Impact factor: 5.157
Authors: Kalev Nõupuu; Winston Lee; Jana Zernant; Stephen H Tsang; Rando Allikmets Journal: Invest Ophthalmol Vis Sci Date: 2014-10-09 Impact factor: 4.799
Authors: Michalis Georgiou; Anthony G Robson; Kaoru Fujinami; Shaun M Leo; Ajoy Vincent; Fadi Nasser; Thales Antônio Cabral De Guimarães; Samer Khateb; Nikolas Pontikos; Yu Fujinami-Yokokawa; Xiao Liu; Kazushige Tsunoda; Takaaki Hayashi; Mauricio E Vargas; Alberta A H J Thiadens; Emanuel R de Carvalho; Xuan-Thanh-An Nguyen; Gavin Arno; Omar A Mahroo; Maria Inmaculada Martin-Merida; Belen Jimenez-Rolando; Gema Gordo; Ester Carreño; Ayuso Carmen; Dror Sharon; Susanne Kohl; Rachel M Huckfeldt; Bernd Wissinger; Camiel J F Boon; Eyal Banin; Mark E Pennesi; Arif O Khan; Andrew R Webster; Eberhart Zrenner; Elise Héon; Michel Michaelides Journal: Am J Ophthalmol Date: 2020-12-11 Impact factor: 5.258