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Boothman I, Clayton LM, McCormack M, Driscoll AM, Stevelink R, Moloney P, Krause R, Kunz WS, Diehl S, O’Brien TJ, Sills GJ, de Haan GJ, Zara F, Koeleman BP, Depondt C, Marson AG, Stefansson H, Stefansson K, Craig J, Johnson MR, Striano P, Lerche H, Furney SJ, Delanty N, Sisodiya SM, Cavalleri GL. Testing for pharmacogenomic predictors of ppRNFL thinning in individuals exposed to vigabatrin. Front Neurosci 2023; 17:1156362. [PMID: 37790589 PMCID: PMC10542409 DOI: 10.3389/fnins.2023.1156362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/25/2023] [Indexed: 10/05/2023] Open
Abstract
Background The anti-seizure medication vigabatrin (VGB) is effective for controlling seizures, especially infantile spasms. However, use is limited by VGB-associated visual field loss (VAVFL). The mechanisms by which VGB causes VAVFL remains unknown. Average peripapillary retinal nerve fibre layer (ppRNFL) thickness correlates with the degree of visual field loss (measured by mean radial degrees). Duration of VGB exposure, maximum daily VGB dose, and male sex are associated with ppRNFL thinning. Here we test the hypothesis that common genetic variation is a predictor of ppRNFL thinning in VGB exposed individuals. Identifying pharmacogenomic predictors of ppRNFL thinning in VGB exposed individuals could potentially enable safe prescribing of VGB and broader use of a highly effective drug. Methods Optical coherence topography (OCT) and GWAS data were processed from VGB-exposed individuals (n = 71) recruited through the EpiPGX Consortium. We conducted quantitative GWAS analyses for the following OCT measurements: (1) average ppRNFL, (2) inferior quadrant, (3) nasal quadrant, (4) superior quadrant, (5) temporal quadrant, (6) inferior nasal sector, (7) nasal inferior sector, (8) superior nasal sector, and (9) nasal superior sector. Using the summary statistics from the GWAS analyses we conducted gene-based testing using VEGAS2. We conducted nine different PRS analyses using the OCT measurements. To determine if VGB-exposed individuals were predisposed to having a thinner RNFL, we calculated their polygenic burden for retinal thickness. PRS alleles for retinal thickness were calculated using published summary statistics from a large-scale GWAS of inner retinal morphology using the OCT images of UK Biobank participants. Results The GWAS analyses did not identify a significant association after correction for multiple testing. Similarly, the gene-based and PRS analyses did not reveal a significant association that survived multiple testing. Conclusion We set out to identify common genetic predictors for VGB induced ppRNFL thinning. Results suggest that large-effect common genetic predictors are unlikely to exist for ppRNFL thinning (as a marker of VAVFL). Sample size was a limitation of this study. However, further recruitment is a challenge as VGB is rarely used today because of this adverse reaction. Rare variants may be predictors of this adverse drug reaction and were not studied here.
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Affiliation(s)
- Isabelle Boothman
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
- The SFI Futureneuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland
- The SFI Centre for Research Training in Genomics Data Science, Galway, Ireland
| | - Lisa M. Clayton
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
- Chalfont Centre for Epilepsy, Bucks, United Kingdom
| | - Mark McCormack
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | | | - Remi Stevelink
- Department of Genetics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Patrick Moloney
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Roland Krause
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Wolfram S. Kunz
- Division of Neurochemistry, Department of Epileptology, University Bonn Medical Center, Bonn, Germany
| | - Sarah Diehl
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Terence J. O’Brien
- Departments of Neuroscience and Neurology, Central Clinical School, The Alfred Hospital, Monash University, Melbourne, VIC, Australia
| | - Graeme J. Sills
- School of Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Gerrit-Jan de Haan
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
| | - Federico Zara
- "IRCCS”G. Gaslini" Institute, Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genova, Italy
| | - Bobby P. Koeleman
- Department of Genetics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Chantal Depondt
- Department of Neurology, Hôpital Erasme, Hôpital Universitaire de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
| | - Anthony G. Marson
- Department of Pharmacology and Therapeutics, University of Liverpool, Liverpool, United Kingdom
| | | | | | - John Craig
- Department of Neurology, Royal Victoria Hospital, Belfast Health and Social Care Trust, Belfast, United Kingdom
| | - Michael R. Johnson
- Division of Brain Sciences, Imperial College Faculty of Medicine, London, United Kingdom
| | - Pasquale Striano
- "IRCCS”G. Gaslini" Institute, Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genova, Italy
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Simon J. Furney
- Genomic Oncology Research Group, Deptartment of Physiology and Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Norman Delanty
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Sanjay M. Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
- Chalfont Centre for Epilepsy, Bucks, United Kingdom
| | - Gianpiero L. Cavalleri
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
- The SFI Futureneuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland
- The SFI Centre for Research Training in Genomics Data Science, Galway, Ireland
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Murray IC, Cameron LA, McTrusty AD, Perperidis A, Brash HM, Fleck BW, Minns RA. Feasibility, Accuracy, and Repeatability of Suprathreshold Saccadic Vector Optokinetic Perimetry. Transl Vis Sci Technol 2016; 5:15. [PMID: 27617181 PMCID: PMC5015923 DOI: 10.1167/tvst.5.4.15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 06/14/2016] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate feasibility, accuracy, and repeatability of suprathreshold Saccadic Vector Optokinetic Perimetry (SVOP) by comparison with Humphrey Field Analyzer (HFA) perimetry. Methods The subjects included children with suspected field defects (n = 10, age 5–15 years), adults with field defects (n = 33, age 39–78 years), healthy children (n = 12, age 6–14 years), and healthy adults (n = 30, age 16–61 years). The test protocol comprised repeat suprathreshold SVOP and HFA testing with the C-40 test pattern. Feasibility was assessed by protocol completeness. Sensitivity, specificity, and accuracy of SVOP was established by comparison with reliable HFA tests in two ways: (1) visual field pattern results (normal/abnormal), and (2) individual test point outcomes (seen/unseen). Repeatability of each test type was assessed using Cohen's kappa coefficient. Results Of subjects, 82% completed a full protocol. Poor reliability of HFA testing in child patients limited the robustness of comparisons in this group. Sensitivity, specificity, and accuracy across all groups when analyzing the visual field pattern results was 90.9%, 88.5%, and 89.0%, respectively, and was 69.1%, 96.9%, and 95.0%, respectively, when analyzing the individual test points. Cohen's kappa coefficient for repeatability of SVOP and HFA was excellent (0.87 and 0.88, respectively) when assessing visual field pattern results, and substantial (0.62 and 0.74, respectively) when assessing test point outcomes. Conclusions SVOP was accurate in this group of adults. Further studies are required to assess SVOP in child patient groups. Translational Relevance SVOP technology is still in its infancy but is used in a number of centers. It will undergo iterative improvements and this study provides a benchmark for future iterations.
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Affiliation(s)
- Ian C Murray
- University of Edinburgh, Edinburgh, Scotland, UK
| | - Lorraine A Cameron
- University of Edinburgh, Edinburgh, Scotland, UK ; Glasgow Caledonian University, Glasgow, Scotland, UK
| | - Alice D McTrusty
- University of Edinburgh, Edinburgh, Scotland, UK ; Glasgow Caledonian University, Glasgow, Scotland, UK
| | - Antonios Perperidis
- University of Edinburgh, Edinburgh, Scotland, UK ; Heriot Watt University, Edinburgh, Scotland, UK
| | | | - Brian W Fleck
- University of Edinburgh, Edinburgh, Scotland, UK ; Princess Alexandra Eye Pavilion, Edinburgh, Scotland, UK ; Royal Hospital for Sick Children, Edinburgh, Scotland, UK
| | - Robert A Minns
- University of Edinburgh, Edinburgh, Scotland, UK ; Royal Hospital for Sick Children, Edinburgh, Scotland, UK
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3
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Curatolo P, D’Argenzio L, Cerminara C, Bombardieri R. Management of epilepsy in tuberous sclerosis complex. Expert Rev Neurother 2014; 8:457-67. [DOI: 10.1586/14737175.8.3.457] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kjellström U, Andréasson S, Ponjavic V. Electrophysiological evaluation of retinal function in children receiving vigabatrin medication. J Pediatr Ophthalmol Strabismus 2011; 48:357-65. [PMID: 21261244 DOI: 10.3928/01913913-20110118-01] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 12/01/2010] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate retinal function in children taking vigabatrin and to explore the influence of age and dose parameters on the results of full-field electroretinography (ff-ERG). METHODS The ff-ERGs from 14 children receiving vigabatrin were compared with ff-ERGs from healthy controls. Treated children were further grouped according to age (pre-school = 12-71 months; older = 72-228 months). Parameters of drug dosage were compared. RESULTS Treated children showed rod and cone dysfunction reflected by reduced b-wave amplitudes for the isolated rod response, the combined rod-cone response, and the 30-Hz flicker response. The a-wave amplitude and implicit time for the combined rod-cone response, reflecting photoreceptor function, were also altered. Further evaluation of age groups revealed similar findings in the pre-school group but not in the older group. Alterations in ff-ERG were seen in 57% of the treated children. Pre-school children had received significantly higher daily drug doses with start of medication at younger age. No differences were found concerning cumulative doses or duration of medication. CONCLUSION Alterations in ff-ERG are as frequent in children as in adults and the results indicate that exposure to high daily doses of vigabatrin may be associated with increased risk of retinal dysfunction, including photoreceptor damage, not previously shown in children. Thus, recommendations of careful follow-up for children receiving vigabatrin are supported.
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Moseng L, Sæter M, Mørch-Johnsen GH, Hoff JM, Gajda A, Brodtkorb E, Midelfart A. Retinal nerve fibre layer attenuation: clinical indicator for vigabatrin toxicity. Acta Ophthalmol 2011; 89:452-8. [PMID: 21251242 DOI: 10.1111/j.1755-3768.2010.02077.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To investigate whether persistent visual field defects among patients exposed once to the antiepileptic drug vigabatrin (VGB) were associated with peripapillary retinal nerve fibre layer thickness (RNFLT) attenuation. METHODS Nine individuals with partial epilepsy and VGB-attributed visual field loss (group 1; 18 eyes) and seven age- and gender-matched individuals with epilepsy and no previous VGB exposure (group 2; 14 eyes) were included in the study. Full-field 120 point screening perimetry out to 60 degrees from central fixation using the Humphrey Field Analyzer was performed. RNFLT was quantified by optical coherence tomography (OCT) using Fast RNFLT protocol, Stratus OCT (3.0) after pupillary dilation. The results from the right eye are presented in this article. RESULTS Among the patients with VGB-attributed visual field loss, five patients had only peripheral field defect (group 1a) and the remaining four had advanced field defects both in the periphery and within 30° from central fixation (group 1b). None of the patients in the control group had manifest visual field loss. The mean RNFLT among the patients with VGB-attributed visual field loss was significantly attenuated compared to the controls [mean total RNFLT: group 1: 75.6 ± 12.7 μm, group 2: 103.5 ± 9.7 μm, mean difference 27.9 μm, (CI 15.9-39.9; p < 0.001)]. RNFLT values classified as borderline according to normative database (Stratus OCT) occurred more frequently among individuals with VGB-attributed visual field loss than in controls (frequency in group 1: 6/9; group 2: 0/7, p = 0.011). The nasal, superior and inferior quadrants of RNFLT in individuals with VGB-attributed visual field loss were significantly attenuated, while no difference was detected in temporal quadrants compared to controls. Both individuals with peripheral and those with advanced visual field losses in the VGB group had attenuated mean total RNFLT compared to controls (p = 0.006, p = 0.002, respectively). Occurrence of borderline classification of total RNFLT ≤5th percentile was more frequent among individuals with advanced visual field loss than among controls (p = 0.048). CONCLUSION Persistent visual field loss attributed to VGB is associated with reduced peripapillary RNFLT and was detected both among patients with advanced and among patients with only peripheral visual field defects. Measurements of RNFLT with OCT might be considered as a diagnostic supplement in the follow-up of patients exposed to vigabatrin.
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Affiliation(s)
- Linda Moseng
- Institute of Neuroscience, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway
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Maguire MJ, Hemming K, Wild JM, Hutton JL, Marson AG. Prevalence of visual field loss following exposure to vigabatrin therapy: A systematic review. Epilepsia 2010; 51:2423-31. [DOI: 10.1111/j.1528-1167.2010.02772.x] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
The newer antiepileptic drugs (AEDs) provide more therapeutic options and overall improved safety and tolerability for patients. To provide the best care, physicians must be familiar with the latest tolerability and safety data. This is particularly true in children, given there are relatively fewer studies examining the effects of AEDs in children compared with adults. Since we now have significant paediatric literature on each of these agents, we provide a comprehensive and current literature review of the newer AEDs, focusing on safety and tolerability data in children and adolescents. Because the safety profiles in children differ from those in adults, familiarity with this literature is important for child neurologists and other paediatric caregivers. We have organized the data by organ system for each AED for easier reference.
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Affiliation(s)
- Dean P Sarco
- Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Children's Hospital Boston, Boston, Massachusetts, USA.
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Riikonen RS. Favourable prognostic factors with infantile spasms. Eur J Paediatr Neurol 2010; 14:13-8. [PMID: 19362867 DOI: 10.1016/j.ejpn.2009.03.004] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 03/28/2009] [Accepted: 03/29/2009] [Indexed: 11/29/2022]
Abstract
The following aspects are reviewed: Does the aetiology influence the outcome of infantile spasms? Does the treatment influence the outcome? Can the outcome be predicted? Can we improve the prognosis? Favourable factors are the following: cryptogenic aetiology, age at onset > or =4 months, absence of atypical spasms and partial seizures, and absence of asymmetrical EEG abnormalities, short treatment lag, and an early and sustained response to treatment. Not only patients with a cryptogenic aetiology have a favourable outcome. We can already at the first clinical evaluation tell the parents if the prognosis looks favourable. The final goal of the treatment is improved mental outcome. Steroids and vigabatrin are the first-line drugs for infantile spasms in Europe. In a prospective study from the United Kingdom short-term outcome was better with hormonal than with vigabatrin therapy (tuberous sclerosis excluded). However, the numbers of patients who were seizure-free at 3-4 months in different studies have been very similar. Moreover, an early response to treatment seems to be of predictive value for the cognitive outcome in children with cryptogenic spasms. The long-term outcome is known only after hormonal therapy. The side effects of steroids are usually treatable and reversible. In Finland ACTH therapy is given at the minimum effective dose and for the minimum effective time with minimal side effects. The risks of VGB are irreversible visual field defects. As of yet there is no method to examine the visual fields in patients with infantile spasms. Early treatment of infantile spasms seems to be important. Prevention of infantile spasms with some aetiological groups might be possible.
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Affiliation(s)
- Raili S Riikonen
- Kuopio University Hospital, Kuopio, P.O. Box 1627, FI-70211 Kuopio, Finland.
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Durbin S, Mirabella G, Buncic JR, Westall CA. Reduced grating acuity associated with retinal toxicity in children with infantile spasms on vigabatrin therapy. Invest Ophthalmol Vis Sci 2009; 50:4011-6. [PMID: 19279311 DOI: 10.1167/iovs.08-3237] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To determine whether visual functions are decreased in children with infantile spasms and vigabatrin-attributed retinal toxicity. METHODS Contrast sensitivity and grating acuity were measured by using sweep visual evoked potential (VEP) testing in 42 children with infantile spasms (mean age, 29.23 +/- 18.31 months). All children had been exposed to vigabatrin (VGB) for a minimum of 1 month. These children were divided into retinal toxicity and no toxicity groupings based on 30-Hz flicker amplitude reductions on the full-field electroretinogram. A multivariate analysis of variance (MANOVA) compared visual functions between children with and without retinal toxicity. RESULTS The MANOVA showed that visual function was significantly affected by VGB retinal toxicity. Further univariate analysis revealed that grating acuity was significantly reduced in children with toxicity. No differences in contrast sensitivity were found between children with toxicity and those without. CONCLUSIONS Reduced visual functions from VGB-attributed retinal toxicity can be detected in children with infantile spasms with the sweep VEP.
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Affiliation(s)
- Sivan Durbin
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
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10
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Petzold A, Plant GT. Central and Paracentral Visual Field Defects and Driving Abilities. Ophthalmologica 2008; 219:191-201. [PMID: 16088237 DOI: 10.1159/000085727] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Accepted: 08/19/2004] [Indexed: 12/29/2022]
Abstract
The effect of central and paracentral visual field defects on driving abilities has until now received little attention. To date studies and surveys have concentrated on visual acuity and peripheral field loss. Here we summarise for the first time those diseases causing central visual field defects likely to be associated with binocular visual acuity adequate for driving.
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Affiliation(s)
- A Petzold
- Department of Neuroimmunology, Institute of Neurology, London, UK.
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11
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Conway M, Cubbidge RP, Hosking SL. Visual Field Severity Indices Demonstrate Dose-Dependent Visual Loss from Vigabatrin Therapy. Epilepsia 2008; 49:108-16. [DOI: 10.1111/j.1528-1167.2007.01249.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Parisi P, Bombardieri R, Curatolo P. Current role of vigabatrin in infantile spasms. Eur J Paediatr Neurol 2007; 11:331-6. [PMID: 17625936 DOI: 10.1016/j.ejpn.2007.03.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 03/25/2007] [Accepted: 03/26/2007] [Indexed: 11/22/2022]
Abstract
Vigabatrin (VGB), a selective irreversible inhibitor of gamma-aminobutyric acid transaminase, has proved to be effective against cryptogenic and symptomatic infantile spasms (IS). Unfortunately, reports of serious visual field defects have led to a drastic reduction in the use of the drug. This review is based on a systematic search in the literature for evidence regarding efficacy and safety of VGB in IS. Based on a specific mechanism of action, there is a solid evidence of clinical efficacy of VGB in children with Tuberous Sclerosis. Similarly, VGB could represent a potential effective therapy also for spasms due to focal cortical dysplasia. In infants with spasms due to other causes, the risk of ophthalmologic toxicity should be carefully weighted against the benefit of controlling spasms.
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Affiliation(s)
- Pasquale Parisi
- Child Neurology & Paediatric Sleep Centre, La Sapienza II University c/o Sant'Andrea Hospital, Rome, Italy
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McDonald DGM, Najam Y, Keegan MB, Whooley M, Madden D, McMenamin JB. The use of lamotrigine, vigabatrin and gabapentin as add-on therapy in intractable epilepsy of childhood. Seizure 2005; 14:112-6. [PMID: 15694564 DOI: 10.1016/j.seizure.2004.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
PURPOSE Lamotrigine (LTG), vigabatrin (VGB) and gabapentin (GBP) are three anti-epileptic drugs (AEDs) used in the treatment of children with epilepsy for which long-term retention rates are not currently well known. This study examines the efficacy, long-term survival and adverse event profile of these three agents used as add-on therapy in children with refractory epilepsy over a 10-year period. METHODS Three separate audits were conducted between February 1996 and September 2000. All children studied had epilepsy refractory to other AEDs. Efficacy was confirmed if a patient became seizure free or achieved >50% reduction in seizure frequency for 6 months or more after starting therapy. Adverse events and patient survival for each drug were recorded at the end of the study period. RESULTS Between September 1990 and February 1996, 132 children received LTG, 80 VGB and 39 GBP. At the 10-year follow-up audit, 33% of the children on LTG had a sustained beneficial effect on their seizure frequency in contrast to 19% for VGB and 15% for GBP. No significant difference in efficacy was found in children with partial seizures. Children with epileptic encephalopathy (EE) including myoclonic-astatic epilepsy and Lennox-Gastaut Syndrome (LGS) achieved a more favorable response to LTG. The main reasons for drug withdrawal were lack of efficacy for VGB, apparent worsening of seizures for GBP and the development of a rash for LTG. CONCLUSIONS Lamotrigine is a useful add-on therapy in treating children with epilepsy. It has a low adverse event profile and a sustained beneficial effect in children with intractable epilepsy.
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Affiliation(s)
- D G M McDonald
- Neurology Department, Our Lady's Hospital for Sick Children, Crumlin, Dublin 12, Ireland
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Buncic JR, Westall CA, Panton CM, Munn JR, MacKeen LD, Logan WJ. Characteristic retinal atrophy with secondary "inverse" optic atrophy identifies vigabatrin toxicity in children. Ophthalmology 2004; 111:1935-42. [PMID: 15465561 PMCID: PMC3880364 DOI: 10.1016/j.ophtha.2004.03.036] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2003] [Accepted: 03/15/2004] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To describe the clinical pattern of retinal atrophy in children caused by the anticonvulsant vigabatrin. DESIGN An interventional case series report. PARTICIPANTS One hundred thirty-eight patients, mainly infants, were evaluated regularly for evidence of possible vigabatrin toxicity in the Eye and Neurology clinics at the Hospital for Sick Children, Toronto. METHOD Sequential clinical and electroretinographic (International Society for Clinical Electrophysiology of Vision standards) evaluations every 6 months. MAIN OUTCOME MEASURES Presence of recognizable retinal and optic atrophy in the presence of abnormal electroretinogram (ERG) and other clinical findings. RESULTS Three children being treated for seizures with vigabatrin showed definite clinical findings of peripheral retinal nerve fiber layer atrophy, with relative sparing of the central or macular portion of the retina and relative nasal optic nerve atrophic changes. Some macular wrinkling was evident in 1 case. Progressive ERG changes showing decreased responses, especially the 30-Hz flicker response, supported the presence of decreased retinal function. CONCLUSIONS A recognizable and characteristic form of peripheral retinal atrophy and nasal or "inverse" optic disc atrophy can occur in a small number of children being treated with vigabatrin. The changes in superficial light reflexes of the retina in children facilitate the clinical recognition of nerve fiber layer atrophy. The macula is relatively spared, although superficial retinal light reflexes indicating wrinkling of the innermost retina suggest early macular toxicity as well. Because these changes are accompanied by electrophysiologic evidence of retinal dysfunction, discontinuation of vigabatrin should be strongly considered.
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Affiliation(s)
- J Raymond Buncic
- Department of Ophthalmology, The Hospital for Sick Children, Toronto, ON, Canada
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15
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Abstract
Up-to date information about corticotropin (ACTH) in the treatment of infantile spasms and evaluation of the long-term outcome was provided to answer questions about (1) the efficacy of doses of ACTH in comparison with other drugs, especially with vigabatrin, and the efficacy in patients with tuberous sclerosis; (2) tolerability; and (3) long-term outcome. In two studies, high doses were not more effective than low doses but were more effective in another study. In the follow-up of the studies, there was no difference. In an open, randomized, prospective study, the efficacy and relapse rates of ACTH and vigabatrin treatment did not differ significantly. The high response rates in tuberous sclerosis complex were similar. Both drugs had severe side effects. In the long-term follow-up of 20 to 35 years, one third of the patients died, the intellectual outcome of the remaining patients was normal or slightly subnormal, and one quarter and one third of the patients were seizure free. ACTH should be the first choice for treatment of infantile spasms. The side effects of ACTH, unlike those of vigabatrin, are well known, treatable, and reversible. However, an open, prospective study to compare the efficacy, relapse rate, and long-term outcome of treatment with ACTH and vigabatrin is urgently needed. The frequency of visual field defects after vigabatrin therapy should be evaluated.
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Affiliation(s)
- Raili Riikonen
- Department of Child Neurology, Children's Hospital, University of Kuopio, Kuopio, Finland.
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Westall CA, Nobile R, Morong S, Buncic JR, Logan WJ, Panton CM. Changes in the electroretinogram resulting from discontinuation of vigabatrin in children. Doc Ophthalmol 2004; 107:299-309. [PMID: 14711162 PMCID: PMC3880365 DOI: 10.1023/b:doop.0000005339.23258.8f] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Electroretinograms (ERGs) have been recorded longitudinally in children before and during treatment with the antiepileptic drug vigabatrin for the past 3.5 years. Vigabatrin induced changes in ERG responses occur in children; the most dramatic changes occur in the oscillatory potentials. The purpose of this study was to identify changes in ERG responses associated with discontinuation of vigabatrin treatment. If vigabatrin-induced changes reverse after discontinuation of the drug we infer that the original change is not an indicator of toxicity. ERG data were analyzed from 17 children who discontinued vigabatrin therapy. The duration of treatment ranged from 5 to 52 months, the age for the first ERG ranged from 6 to 38 months (median 10 months). ERGs were tested using the standard protocol established by the International Society for Clinical Electrophysiology of Vision, with Burian-Allen bipolar contact-lens electrodes. In addition to standard responses we recorded photopic oscillatory potentials (OPs). During vigabatrin treatment OPs show a greater change than other ERG responses, with the early occurring wavelets from the photopic OPs showing the greatest change. With discontinuation of vigabatrin the amplitude of the early wavelets of the photopic OPs increased dramatically compared with amplitudes while taking the drug (paired t-test, p = 0.000075). The scotopic oscillatory potentials also show some recovery. Although changes in oscillatory potentials may occur with vigabatrin toxicity, a large change likely occurs with a non-toxic pharmacological effect of vigabatrin on GABAergic amacrine cells in the inner plexiform layer. Reduction of OPs in children on vigabatrin may not be related to toxicity.
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Affiliation(s)
- Carol A Westall
- Department of Ophthalmology, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
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17
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Ascaso FJ, Lopez MJ, Mauri JA, Cristobal JA. Visual field defects in pediatric patients on vigabatrin monotherapy. Doc Ophthalmol 2004; 107:127-30. [PMID: 14661902 DOI: 10.1023/a:1026237730283] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
UNLABELLED Vigabatrin (GVG) is an effective antiepileptic drug used for treating partial seizures in adults and children. Over the last years, an increasing number of articles have been published reporting visual field defects (VFD) associated with GVG therapy in adults. To date, however, only an small number of pediatric patients have been reported. This paper is a retrospective review of clinical review to evaluate the prevalence and features of VFD in pediatric patients on GVG monotherapy. METHODS Fifteen children, on GVG therapy in the Department of Child Neurology, underwent visual field examination by static threshold automated perimetry using the Humphrey Field Analyzer Program 30-2. The age of these patients ranged from 6 to 18 years (12.4 +/- 3.6 years), 10 of them being male and five female. RESULTS Three patients (20%) on GVG monotherapy showed VFD. These consisted in localised, bilateral, and relatively symmetrical, nasal field loss, with relative preservation of the temporal field within the central 30 degree area.
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Affiliation(s)
- Francisco J Ascaso
- Department of Ophthalmology, University Clinic Hospital, Zaragoza, Spain.
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18
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Abstract
AIMS To report the discovery of a previously unknown form of optic atrophy associated with use of the anti-epileptic drug vigabatrin. METHODS We conducted a retrospective analysis of digitally enhanced ocular fundus photographs, kinetic visual field maps and treatment parameters for 25 patients, who were selected to represent a large spectrum of visual field defects. RESULTS In all, 21 patients (84%) evidenced subtle, diffuse atrophy of the retinal nerve fibre layer, in a pattern accessible to scoring. Atrophy scores correlated with visual field remains and cumulative vigabatrin doses. A pathophysiological model is proposed that involves the lengths of intraocular (unmyelinated) retinal ganglion cell axons. CONCLUSION Optic atrophy attests to the irreversible nature of vigabatrin's visual toxicity. Ocular fundus imaging should prove useful for objectively monitoring vigabatrin-treated subjects for visual toxicity.
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Affiliation(s)
- Lars Frisén
- Institute of Clinical Neuroscience, Sahlgren's Academy at Gothenburg University, SE-413 45 Gothenburg, Sweden.
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Hilton EJR, Cubbidge RP, Hosking SL, Betts T, Comaish IF. Patients treated with vigabatrin exhibit central visual function loss. Epilepsia 2002; 43:1351-9. [PMID: 12423385 DOI: 10.1046/j.1528-1157.2002.00502.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To investigate visual function in the central 10 degrees in patients who have undergone vigabatrin (VGB) antiepileptic drug (AED) therapy with the aim of identifying a clinical regimen for assessing central visual function. METHODS The sample comprised 12 epilepsy patients (mean age, 38.6 +/- 11.7 years) who had been treated with VGB (either as monotherapy or polytherapy). A number of central visual-function tests were carried out for each eye, including high-contrast LogMAR visual acuity, short-wavelength automated perimetry (SWAP 10-2), spatial contrast sensitivity (CSV-1000), and Farnsworth-Munsell (FM) 100-hue colour discrimination. RESULTS The group mean cumulative VGB dose was 5,086 +/- 3,245 g. The average SWAP 10-2 mean deviation (MD) for the group was -3.24 +/- 3.23 dB; 14 eyes of eight patients showed defects (range, -1.62 to -9.46 dB). The square root of the group mean total error score for FM 100-hue was 7.42 +/- 3.84; nine eyes of five patients were classified as abnormal with an unsolved colour axis suggestive of complex drug interactions. For contrast sensitivity, 15 eyes of eight patients yielded abnormal results in one or more spatial frequencies. Defects were more prominent at higher spatial frequencies. Overall, four patients had defects in all three visual-function tests, six patients had mixed defects, and two patients were normal. CONCLUSIONS Visual-function deficits in epilepsy patients treated with VGB are present in the central 10 degrees of the retina. We recommend a battery of investigations, including SWAP 10-2 and spatial contrast sensitivity testing, to assess central visual function.
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Affiliation(s)
- Emma J Roff Hilton
- Neurosciences Research Institute, Aston University, and Queen Elizabeth Psychiatric Hospital, Birmingham, United Kingdom
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20
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Newman WD, Tocher K, Acheson JF. Vigabatrin associated visual field loss: a clinical audit to study prevalence, drug history and effects of drug withdrawal. Eye (Lond) 2002; 16:567-71. [PMID: 12194070 DOI: 10.1038/sj.eye.6700168] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To survey clinical visual function including quantitative manual perimetry results in a group of patients taking vigabatrin; to assess the severity of any field defects; to tabulate cumulative and daily doses of medication and to assess possible changes in visual function over time. METHOD A prevalence study of 100 out of 183 patients currently attending a tertiary referral epilepsy centre who were taking or had recently discontinued vigabatrin (duration 83-3570 days; mean 1885 days) as part of combination anticonvulsant therapy. Complete neuro-ophthalmic examination including Goldmann kinetic perimetry was performed and monocular mean radial degrees (MRD) to the I/4e isopter calculated. Patients were followed up at 6-monthly intervals for not less than 18 months. RESULTS Acuity and colour vision remained stable in all patients regardless of changes in visual fields. Twenty per cent of patients had significant constriction of their visual field defined as a monocular MRD of 30 degrees or less. Males were significantly more likely to be severely affected than females (P < 0.01). Twenty one patients were followed after discontinuing vigabatrin treatment. Only three of these showed a change in MRD of 10 degrees or more with two deteriorating and one improving. No correlation between treatment duration or cumulative dosage/kg and the severity of defects could be demonstrated. CONCLUSIONS Earlier reports of a high prevalence of both moderate and more serious field defects were confirmed in patients taking vigabatrin but not in epileptic patients taking other anti-convulsants. We found no evidence of progression or resolution of visual field defects on discontinuing the drug, and no relationship between dose history and visual deficit field loss. An idiosyncratic drug reaction within the neurosensory retina may underlie the pathogenesis of the visual field loss in some patients.
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Affiliation(s)
- W D Newman
- Dept of Neuro-ophthalmology, National Hospital for Neurology & Neurosurgery, Queen Square, London WC1N 3BG, UK
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21
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Abstract
We reviewed 20 infants receiving vigabatrin for infantile spasms. Patients were not enrolled in a formal study. All families obtained the medication abroad. Age at initiation of vigabatrin ranged from 1 to 48 months; nine infants had received prior treatment with various antiepileptic medications. Patients were begun on the lowest practical dose of 125-250 mg/day, with gradual daily increments to a target of 100 mg/kg/day, but maintained at the lowest effective dosage. Video electroencephalogram was obtained to document resolution of spasms and hypsarrhythmia. Of 20 infants, 12 responded with cessation of spasms and resolution of hypsarrhythmia, at doses of 25-135 mg/kg/day (median = 58 mg/kg/day). Partial responses were observed in six patients, whereas two had no response at 111 and 125 mg/kg/day. Additional new seizure types developed in three infants after initial response to vigabatrin. Increasing the vigabatrin did not have any clinical benefit. Vigabatrin is an effective, well-tolerated treatment for infantile spasms. The response is dose-independent, suggesting that starting at a low dose and gradually increasing, rather than beginning with an arbitrary 100 mg/kg/day dose is advantageous.
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Affiliation(s)
- Wendy G Mitchell
- Neurology Division, Childrens Hospital Los Angeles, Los Angeles, California 90027, USA
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Vanhatalo S, Nousiainen I, Eriksson K, Rantala H, Vainionpää L, Mustonen K, Aärimaa T, Alen R, Aine MR, Byring R, Hirvasniemi A, Nuutila A, Walden T, Ritanen-Mohammed UM, Karttunen-Lewandowski P, Pohjola LM, Kaksonen S, Jurvelin P, Granström ML. Visual field constriction in 91 Finnish children treated with vigabatrin. Epilepsia 2002; 43:748-56. [PMID: 12102679 DOI: 10.1046/j.1528-1157.2002.17801.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To study the prevalence and features of visual field constrictions (VFCs) associated with vigabatrin (VGB) in children. METHODS A systematic collection of all children with any history of VGB treatment in fifteen Finnish neuropediatric units was performed, and children were included after being able to cooperate reliably in repeated visual field tests by Goldmann kinetic perimetry. This inclusion criterion yielded 91 children (45 boys; 46 girls) between ages 5.6 and 17.9 years. Visual field extent <70 degrees in the temporal meridian was considered abnormal VFC. RESULTS There was a notable variation in visual field extents between successive test sessions and between different individuals. VFCs <70 degrees were found in repeated test sessions in 17 (18.7%) of 91 children. There was no difference in the ages at the study, the ages at the beginning of treatment, the total duration of the treatment, general cognitive performance, or neuroradiologic findings between the patients with normal visual fields and those with VFC, but the patients with VFC had received a higher total dose of VGB. In linear regression analysis, there were statistically significant inverse correlations between the temporal extent of the visual fields and the total dose and the duration of VGB treatment. The shortest duration of VGB treatment associated with VFC was 15 months, and the lowest total dose 914 g. CONCLUSIONS Because of a wide variation in normal visual-field test results in children, the prevalence figures of VFCs are highly dependent on the definition of normality. Although our results confirm the previous findings that VFC may occur in children treated with VGB, our study points out the need to reevaluate critically any suspected VFC to avoid misdiagnosis. Nevertheless, our study suggests that the prevalence of VFC may be lower in children than in adults, and that the cumulative dose of VGB or length of VGB therapy may add to the personal predisposition for developing VFC.
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Affiliation(s)
- Sampsa Vanhatalo
- Unit of Child Neurology, Hospital for Children and Adolescents, University Hospital of Helsinki, Finland.
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Abstract
PURPOSE Vigabatrin is an effective antiepileptic drug but visual field constriction (VFC) is found to be a severe side-effect. The aims have been to investigate whether visual field constriction (VFC) is related to changes in the electroretinography (ERG). METHODS Twenty patients with localisations related epilepsy of whom one half had received vigabatrin were subjected to examination without informing about the treatment given. The eye examination included Goldmann perimetry and ERG. RESULTS All the patients had normal visual acuity. A total of three patients (30%) in the vigabatrin group and none in the control group were found to have VFC. In the vigabatrin group ERG examination were normal in one case, in five cases there were changes scotopic, photopic and in the oscillatory potentials (OP), while the remaining four had changes in two of these parameters. OPs were abnormal in eight of 10 patients. Of the three patients with VFC all had changes in ERG. The four patients with the most severe abnormalities in ERG had received high daily doses of vigabatrin (4 - 6 mg) in a period. In the control group no abnormality was observed in five cases, and in the remaining five changes were present in one or two of the potentials. CONCLUSION It is found that 30% of patients treated with vigabatrin, develop VFC, and none in the control group. Similarly more patients in the vigabatrin group had changes in the ERG as compared to the control group, and the number of abnormal potentials are significantly higher among patients with VFC compared to those without. But the finding of abnormal ERG results is not synonymous with VFC, and this is important to bear in mind when examining patients that cannot cooperate to a VF examination. An individual sensitivity to vigabatrin is supposed, but severe ERG changes occurred in all patients having had high daily doses > or = 4 g.
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Affiliation(s)
- Hanne Jensen
- Department of Pediatric Ophthalmology and Handicap, Center for Handicapped, Glostrup, Denmark
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Nabbout R, Melki I, Gerbaka B, Dulac O, Akatcherian C. Infantile spasms in Down syndrome: good response to a short course of vigabatrin. Epilepsia 2001; 42:1580-3. [PMID: 11879370 DOI: 10.1046/j.1528-1157.2001.13501.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the efficacy of vigabatrin (VGB) in the treatment of infantile spasms (ISs) associated with Down syndrome (DS) and to assess the feasibility of early discontinuation to reduce the possible retinal toxicity. METHODS Five children with ISs with DS were treated with vigabatrin as first-line monotherapy in an open prospective study. The short-term response was evaluated, and VGB was continued in responders. The treatment was stopped after 6 months in children who were still spasm free. RESULTS Four children of five became spasm free with VGB, three of them responding within 1 week. This response was maintained during the 6 months of VGB treatment. After VGB discontinuation, and with a follow-up ranging from 2 to 4 years, none of the responders experienced spasm recurrence or other types of seizures. CONCLUSIONS This study confirms the efficacy of VGB in ISs associated with DS. Moreover, it shows that the duration of VGB treatment can be reduced to 6 months without relapse of ISs. This short treatment might reduce the risk of developing visual field constriction.
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Affiliation(s)
- R Nabbout
- Department of Pediatrics, Hôpital Hôtel Dieu de France, Université St. Joseph, Beirut, Lebanon
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Koul R, Chacko A, Ganesh A, Bulusu S, Al Riyami K. Vigabatrin associated retinal dysfunction in children with epilepsy. Arch Dis Child 2001; 85:469-73. [PMID: 11719329 PMCID: PMC1719022 DOI: 10.1136/adc.85.6.469] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Recent reports have established that eye changes occur in patients treated with vigabatrin. AIM To identify the eye changes associated with vigabatrin, based on a prospective study of children treated for seizures. METHODS Twenty nine children on vigabatrin (mainly as add on therapy) were followed up for 6.5 years. Ophthalmic examination was performed before starting treatment and then six monthly in the outpatient clinic. RESULTS Twenty one children fulfilled the inclusion criteria. Most had epileptic syndromes with infantile spasms-namely West syndrome, Lennox-Gastaut syndrome, and partial seizures. Vigabatrin dose was 25-114 mg/kg/day (mean 55.8); duration of therapy was 6-85 months (mean 35.7). Four children (19%) developed eye changes (retinal pigmentation, hypopigmented retinal spots, vascular sheathing, and optic atrophy). Visual evoked potentials were abnormal in 16 children. Electroretinography and electro-oculography, which could have picked up eye changes in early stages, were not performed, as this facility was not available. CONCLUSIONS Vigabatrin causes eye damage. Most children with epileptic syndromes on vigabatrin cannot complain of their eye problems, hence 3-6 monthly ophthalmic follow up is strongly advised, along with regular electroretinography, electro-oculography, and visual evoked potentials if possible.
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Affiliation(s)
- R Koul
- Department of Child Health, Division of Paediatric Neurology, Sultan Qaboos University Hospital, Al Khod, 123, Sultanate of Oman.
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Pharmacoepidemiology and drug safety. Pharmacoepidemiol Drug Saf 2000; 9:615-30. [PMID: 11338922 DOI: 10.1002/pds.493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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