PURPOSE: Vigabatrin (gamma-vinyl-GABA) is an antiepileptic drug successful in the management of infantile spasms. Photopic ERGs were tested in children followed longitudinally before and during vigabatrin treatment. METHODS: Subjects were 26 infants (age range 1.5-24 months, median 7.6 months) on vigabatrin treatment who had been tested on multiple visits (two to four visits; mean, three visits). Eighteen of these were assessed initially before starting vigabatrin therapy and eight were assessed within 1 week of initiation of the drug. ERGs were recorded at 6-month intervals. Standard ISCEV protocol with Burian-Allen bipolar contact-lens electrodes (standard flash 2.0 cd.s/m2) was used. Although ISCEV standards were followed, a higher flash intensity (set at 3.6 cd.s/m2) was chosen for single-flash cone assessment to provide a better definition of OPs. Photopic OPs were divided into categories of early OPs and late OP (OP4). Responses were compared with age corrected limits extrapolated from our lab control database. RESULTS: Results showed differential effects of vigabatrin on the summed early OP amplitudes versus the late OP (OP4) and cone b-wave amplitude. The early OPs showed significant decrease (p = 0.0005, repeated measures analysis of variance) after 6 months and remained decreased for the duration of treatment. There was no significant change seen in the late OP. The cone b-wave amplitude showed initial increase (p = 0.04) after 6 months, followed by a decrease after 18 months; a trend similar to that of the late OP. CONCLUSION: Early photopic OPs were disrupted more than the late OP, suggesting relative deficit in the ON (depolarizing) retinal pathways.
PURPOSE:Vigabatrin (gamma-vinyl-GABA) is an antiepileptic drug successful in the management of infantile spasms. Photopic ERGs were tested in children followed longitudinally before and during vigabatrin treatment. METHODS: Subjects were 26 infants (age range 1.5-24 months, median 7.6 months) on vigabatrin treatment who had been tested on multiple visits (two to four visits; mean, three visits). Eighteen of these were assessed initially before starting vigabatrin therapy and eight were assessed within 1 week of initiation of the drug. ERGs were recorded at 6-month intervals. Standard ISCEV protocol with Burian-Allen bipolar contact-lens electrodes (standard flash 2.0 cd.s/m2) was used. Although ISCEV standards were followed, a higher flash intensity (set at 3.6 cd.s/m2) was chosen for single-flash cone assessment to provide a better definition of OPs. Photopic OPs were divided into categories of early OPs and late OP (OP4). Responses were compared with age corrected limits extrapolated from our lab control database. RESULTS: Results showed differential effects of vigabatrin on the summed early OP amplitudes versus the late OP (OP4) and cone b-wave amplitude. The early OPs showed significant decrease (p = 0.0005, repeated measures analysis of variance) after 6 months and remained decreased for the duration of treatment. There was no significant change seen in the late OP. The cone b-wave amplitude showed initial increase (p = 0.04) after 6 months, followed by a decrease after 18 months; a trend similar to that of the late OP. CONCLUSION: Early photopic OPs were disrupted more than the late OP, suggesting relative deficit in the ON (depolarizing) retinal pathways.
Authors: James D Akula; Emily R Noonan; Alessia Di Nardo; Tara L Favazza; Nan Zhang; Mustafa Sahin; Ronald M Hansen; Anne B Fulton Journal: Doc Ophthalmol Date: 2015-03-12 Impact factor: 2.379
Authors: J Raymond Buncic; Carol A Westall; Carole M Panton; J Robert Munn; Leslie D MacKeen; William J Logan Journal: Ophthalmology Date: 2004-10 Impact factor: 12.079
Authors: Carol A Westall; Rita Nobile; Sharon Morong; J Raymond Buncic; William J Logan; Carole M Panton Journal: Doc Ophthalmol Date: 2003-11 Impact factor: 2.379
Authors: Carol A Westall; Tom Wright; Filomeno Cortese; Ananthavalli Kumarappah; O Carter Snead; Joseph R Buncic Journal: Neurology Date: 2014-11-07 Impact factor: 9.910
Authors: Kore Chan; Mrinalini Hoon; Bikash R Pattnaik; James N Ver Hoeve; Brad Wahlgren; Shawna Gloe; Jeremy Williams; Brenna Wetherbee; Julie A Kiland; Kara R Vogel; Erwin Jansen; Gajja Salomons; Dana Walters; Jean-Baptiste Roullet; K Michael Gibson; Gillian J McLellan Journal: Invest Ophthalmol Vis Sci Date: 2020-02-07 Impact factor: 4.799