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Multimodal Imaging in Hereditary Retinal Diseases  [PDF]
Francesco Pichi,Mariachiara Morara,Chiara Veronese,Paolo Nucci,Antonio P. Ciardella
Journal of Ophthalmology , 2013, DOI: 10.1155/2013/634351
Abstract: Introduction. In this retrospective study we evaluated the multimodal visualization of retinal genetic diseases to better understand their natural course. Material and Methods. We reviewed the charts of 70 consecutive patients with different genetic retinal pathologies who had previously undergone multimodal imaging analyses. Genomic DNA was extracted from peripheral blood and genotyped at the known locus for the different diseases. Results. The medical records of 3 families of a 4-generation pedigree affected by North Carolina macular dystrophy were reviewed. A total of 8 patients with Stargardt disease were evaluated for their two main defining clinical characteristics, yellow subretinal flecks and central atrophy. Nine male patients with a previous diagnosis of choroideremia and eleven female carriers were evaluated. Fourteen patients with Best vitelliform macular dystrophy and 6 family members with autosomal recessive bestrophinopathy were included. Seven patients with enhanced s-cone syndrome were ascertained. Lastly, we included 3 unrelated patients with fundus albipunctatus. Conclusions. In hereditary retinal diseases, clinical examination is often not sufficient for evaluating the patient’s condition. Retinal imaging then becomes important in making the diagnosis, in monitoring the progression of disease, and as a surrogate outcome measure of the efficacy of an intervention. 1. Introduction Evaluation of the retina is a critical step in understanding and diagnosing genetic disease. Because ophthalmologists can view the retina directly, they are often able to make diagnoses without additional testing. In a number of diseases, however, the clinical examination is not sufficient for evaluating the patient’s condition. Retinal imaging then becomes important in making the diagnosis and in monitoring the progression of disease. It may be used to document and quantify a patient’s symptoms; it may help in making a differential diagnosis of some retinal disorders, in distinguishing localized macular disorders from diffuse retinal disorders, and in distinguishing optic nerve disease from retinal disease. Early alteration of retinal imaging might serve as a surrogate outcome measure of the efficacy of an intervention, rather than waiting for years to determine if a disease has progressed clinically. Diagnostic imaging procedures used for evaluation and followup of retinal genetic disease include colour fundus photography, blue fundus autofluorescence (FAF) [1–3], fluorescein angiography (FA) [4, 5], indocyanine green angiography (ICGA) [6], and
Unilateral electronegative ERG in a presumed central retinal artery occlusion  [cached]
Luiz H Lima,Wener Cella,Claudia Brue,et al
Clinical Ophthalmology , 2010,
Abstract: Luiz H Lima1, Wener Cella2,4, Claudia Brue5, Stephen H Tsang2.31Federal University of Sao Paulo (UNIFESP), Sao Paulo, Brazil; 2Department of Ophthalmology, 3Bernard and Shirlee Brown Glaucoma Laboratory, Edward S Harkness Eye Institute and Departments of Opthamology, Pathology and Cell Biology, Columbia University, New York, NY, USA; 4Department of Ophthalmology, University of Brasilia, Brasilia, Brazil; 5Department of Opthamology, University Politecnica delle Marche, Ancona, ItalyAbstract: A unilateral electronegative electroretinogram (ERG) was seen in a 94-year-old man with presumed central retinal artery occlusion. Goldmann perimetry revealed central scotoma in the right eye and no abnormalities in the left eye. Full-field ERG in the right eye described a reduction of the b-wave with a relative preservation of the a-wave which is characteristic of electronegative ERG. Hence, our case illustrates that ERG testing is essential for the work-up of individuals with suspected retinal vascular disorders.Keywords: central retinal artery occlusion, electronegative ERG, inner retina, spectral domain optical coherence tomography
Unilateral electronegative ERG in a presumed central retinal artery occlusion
Luiz H Lima, Wener Cella, Claudia Brue, et al
Clinical Ophthalmology , 2010, DOI: http://dx.doi.org/10.2147/OPTH.S10374
Abstract: ilateral electronegative ERG in a presumed central retinal artery occlusion Case report (2977) Total Article Views Authors: Luiz H Lima, Wener Cella, Claudia Brue, et al Published Date November 2010 Volume 2010:4 Pages 1311 - 1314 DOI: http://dx.doi.org/10.2147/OPTH.S10374 Luiz H Lima1, Wener Cella2,4, Claudia Brue5, Stephen H Tsang2.3 1Federal University of Sao Paulo (UNIFESP), Sao Paulo, Brazil; 2Department of Ophthalmology, 3Bernard and Shirlee Brown Glaucoma Laboratory, Edward S Harkness Eye Institute and Departments of Opthamology, Pathology and Cell Biology, Columbia University, New York, NY, USA; 4Department of Ophthalmology, University of Brasilia, Brasilia, Brazil; 5Department of Opthamology, University Politecnica delle Marche, Ancona, Italy Abstract: A unilateral electronegative electroretinogram (ERG) was seen in a 94-year-old man with presumed central retinal artery occlusion. Goldmann perimetry revealed central scotoma in the right eye and no abnormalities in the left eye. Full-field ERG in the right eye described a reduction of the b-wave with a relative preservation of the a-wave which is characteristic of electronegative ERG. Hence, our case illustrates that ERG testing is essential for the work-up of individuals with suspected retinal vascular disorders.
Presumed bilateral branch retinal vein occlusions secondary to antiepileptic agents  [cached]
Hussain RN,Banerjee S
Clinical Ophthalmology , 2011,
Abstract: Rumana N Hussain, Somnath BanerjeeLeicester Royal Infirmary, Leicester, UKAbstract: A 61-year-old man presented to the ophthalmology department having developed bilateral branch retinal vein occlusions. Baseline blood tests revealed no abnormality; however, subsequent investigations showed a raised plasma homocysteine (HC) level. The patient has been treated for refractory epilepsy for a number of years. Although antiepileptic medications have been shown to reduce folate levels and result in a raised HC level, this has not previously been shown to be to a level causing a retinal vascular event.Keywords: homocysteine, branch vein occlusions
Presumed bilateral branch retinal vein occlusions secondary to antiepileptic agents
Hussain RN, Banerjee S
Clinical Ophthalmology , 2011, DOI: http://dx.doi.org/10.2147/OPTH.S17754
Abstract: esumed bilateral branch retinal vein occlusions secondary to antiepileptic agents Case report (3321) Total Article Views Authors: Hussain RN, Banerjee S Published Date May 2011 Volume 2011:5 Pages 609 - 611 DOI: http://dx.doi.org/10.2147/OPTH.S17754 Rumana N Hussain, Somnath Banerjee Leicester Royal Infirmary, Leicester, UK Abstract: A 61-year-old man presented to the ophthalmology department having developed bilateral branch retinal vein occlusions. Baseline blood tests revealed no abnormality; however, subsequent investigations showed a raised plasma homocysteine (HC) level. The patient has been treated for refractory epilepsy for a number of years. Although antiepileptic medications have been shown to reduce folate levels and result in a raised HC level, this has not previously been shown to be to a level causing a retinal vascular event.
A case of presumed acute retinal necrosis after intraocular foreign body injury
Park SW, Byon IS, Park HJ, Lee JE, Oum BS
Clinical Ophthalmology , 2013, DOI: http://dx.doi.org/10.2147/OPTH.S42175
Abstract: case of presumed acute retinal necrosis after intraocular foreign body injury Case report (270) Total Article Views Authors: Park SW, Byon IS, Park HJ, Lee JE, Oum BS Published Date March 2013 Volume 2013:7 Pages 545 - 548 DOI: http://dx.doi.org/10.2147/OPTH.S42175 Received: 30 December 2012 Accepted: 07 February 2013 Published: 20 March 2013 Sung Who Park,1 Ik Soo Byon,1 Hyun Jun Park,2 Ji Eun Lee,1,3 Boo Sup Oum1,3 1Department of Ophthalmology, School of Medicine, Pusan National University, Busan, Korea; 2Department of Ophthalmology, Yangsan Pusan National University Hospital, Busan, Korea; 3Medical Research Institute, School of Medicine, Pusan National University Hospital, Busan, Korea Abstract: The aim of this study was to report a case of acute retinal necrosis (ARN) after intraocular foreign body removal. A 32-year-old male presented with visual loss in the left eye. He was hit by an iron fragment while he was hammering. An intraocular foreign body was found with corneal laceration and traumatic cataract. On the day he was injured, primary closure of the laceration, lensectomy, and vitrectomy were performed, and the foreign body was removed. The day after the operation, there was no sign of retinal detachment or retinitis. Two days after the operation, retinal necrosis and accompanying vitreous inflammation were noted in the far periphery. On day 3, the necrosis spread circumferentially and inflammation became more distinct. ARN was presumed and intravenous acyclovir was administered. The necrotic areas were reduced 2 days later, and were resolved in 1 month. The final visual acuity in his left eye was 20/20 after implantation of an intraocular lens. This case is the first report of ARN after penetrating injury and an intraocular foreign body. ARN may develop after open-globe injury.
Conditional Gene Targeting: Dissecting the Cellular Mechanisms of Retinal Degenerations  [PDF]
Yun-Zheng Le
Journal of Ophthalmology , 2011, DOI: 10.1155/2011/806783
Abstract: Retinal neuron degeneration and survival are often regulated by the same trophic factors that are required for embryonic development and are usually expressed in multiple cell-types. Therefore, the conditional gene targeting approach is necessary to investigate the cell-specific function of widely expressed and developmentally regulated genes in retinal degeneration. The discussion in this review will be focused on the use of Cre/lox-based conditional gene targeting approach in mechanistic studies for retinal degeneration. In addition to the basic experimental designs, this article addresses various factors influencing the outcomes of conditional gene targeting studies, limitations of current technologies, availability of Cre-drive lines for various retinal cells, and issues related to the generation of Cre-expressing mice. Finally, this review will update the current status on the use of Cre/lox-based gene targeting approach in mechanistic studies for retinal degeneration, which includes rod photoreceptor survival under photo-oxidative stress and protein trafficking in photoreceptors.
A case of presumed acute retinal necrosis after intraocular foreign body injury  [cached]
Park SW,Byon IS,Park HJ,Lee JE
Clinical Ophthalmology , 2013,
Abstract: Sung Who Park,1 Ik Soo Byon,1 Hyun Jun Park,2 Ji Eun Lee,1,3 Boo Sup Oum1,31Department of Ophthalmology, School of Medicine, Pusan National University, Busan, Korea; 2Department of Ophthalmology, Yangsan Pusan National University Hospital, Busan, Korea; 3Medical Research Institute, School of Medicine, Pusan National University Hospital, Busan, KoreaAbstract: The aim of this study was to report a case of acute retinal necrosis (ARN) after intraocular foreign body removal. A 32-year-old male presented with visual loss in the left eye. He was hit by an iron fragment while he was hammering. An intraocular foreign body was found with corneal laceration and traumatic cataract. On the day he was injured, primary closure of the laceration, lensectomy, and vitrectomy were performed, and the foreign body was removed. The day after the operation, there was no sign of retinal detachment or retinitis. Two days after the operation, retinal necrosis and accompanying vitreous inflammation were noted in the far periphery. On day 3, the necrosis spread circumferentially and inflammation became more distinct. ARN was presumed and intravenous acyclovir was administered. The necrotic areas were reduced 2 days later, and were resolved in 1 month. The final visual acuity in his left eye was 20/20 after implantation of an intraocular lens. This case is the first report of ARN after penetrating injury and an intraocular foreign body. ARN may develop after open-globe injury.Keywords: necrotizing herpetic retinopathy, acute retinal necrosis, intraocular foreign body
Conditional Gene Targeting: Dissecting the Cellular Mechanisms of Retinal Degenerations  [PDF]
Yun-Zheng Le
Journal of Ophthalmology , 2011, DOI: 10.1155/2011/806783
Abstract: Retinal neuron degeneration and survival are often regulated by the same trophic factors that are required for embryonic development and are usually expressed in multiple cell-types. Therefore, the conditional gene targeting approach is necessary to investigate the cell-specific function of widely expressed and developmentally regulated genes in retinal degeneration. The discussion in this review will be focused on the use of Cre/lox-based conditional gene targeting approach in mechanistic studies for retinal degeneration. In addition to the basic experimental designs, this article addresses various factors influencing the outcomes of conditional gene targeting studies, limitations of current technologies, availability of Cre-drive lines for various retinal cells, and issues related to the generation of Cre-expressing mice. Finally, this review will update the current status on the use of Cre/lox-based gene targeting approach in mechanistic studies for retinal degeneration, which includes rod photoreceptor survival under photo-oxidative stress and protein trafficking in photoreceptors. 1. Introduction The use of gene targeting with homologous recombination in murine embryonic stem (ES) cells has led to many mechanistic insights about human diseases. However, global gene disruption has two major limitations that may prevent the identification of gene function in a target tissue or in adults. First, disruption of essential genes often causes embryonic or early postnatal lethality [1]. Second, disruption of a ubiquitously expressed gene may not yield mechanistic insights regarding the function of a protein of interest in a particular cell type [2, 3]. In these scenarios, temporal or/and spatial gene disruption is far more advantageous. The seminal work on the utilization of bacteriophage P1 site-specific recombination system in mammals by Dr. Brian Sauer and his coworkers [4, 5] established a firm foundation for the Cre/lox-based gene targeting, which is the most widely used conditional gene targeting approach to date. Cre recombinase is a 38?kDa protein and belongs to the integrase family of recombinases [6]. Biochemically Cre catalyzes site-specific DNA recombination, both intra- and intermolecularly, between the 34 base pair loxP sites [7]. Cre carries a eukaryotic nuclear targeting sequence [8] and is efficient in performing site-specific DNA recombination in mammals [9]. Therefore, Cre/lox system has become the primary choice for the site-specific DNA recombination-based manipulation of the mouse genome. Efficient Cre-mediated excision of DNA between
Retinal iron homeostasis in health and disease  [PDF]
Delu Song,Joshua L. Dunaief
Frontiers in Aging Neuroscience , 2013, DOI: 10.3389/fnagi.2013.00024
Abstract: Iron is essential for life, but excess iron can be toxic. As a potent free radical creator, iron generates hydroxyl radicals leading to significant oxidative stress. Since iron is not excreted from the body, it accumulates with age in tissues, including the retina, predisposing to age-related oxidative insult. Both hereditary and acquired retinal diseases are associated with increased iron levels. For example, retinal degenerations have been found in hereditary iron overload disorders, like aceruloplasminemia, Friedreich's ataxia, and pantothenate kinase-associated neurodegeneration. Similarly, mice with targeted mutation of the iron exporter ceruloplasmin and its homolog hephaestin showed age-related retinal iron accumulation and retinal degeneration with features resembling human age-related macular degeneration (AMD). Post mortem AMD eyes have increased levels of iron in retina compared to age-matched healthy donors. Iron accumulation in AMD is likely to result, in part, from inflammation, hypoxia, and oxidative stress, all of which can cause iron dysregulation. Fortunately, it has been demonstrated by in vitro and in vivo studies that iron in the retinal pigment epithelium (RPE) and retina is chelatable. Iron chelation protects photoreceptors and retinal pigment epithelial cells (RPE) in a variety of mouse models. This has therapeutic potential for diminishing iron-induced oxidative damage to prevent or treat AMD.
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