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Petrovic Pajic S, Fakin A, Sustar Habjan M, Jarc-Vidmar M, Hawlina M. Leber Hereditary Optic Neuropathy (LHON) in Patients with Presumed Childhood Monocular Amblyopia. J Clin Med 2023; 12:6669. [PMID: 37892808 PMCID: PMC10607696 DOI: 10.3390/jcm12206669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND Most Leber hereditary optic neuropathy (LHON) cases are bilateral and sequential; however, there are rare unilateral examples, or those in which the delay of onset of vision loss between one and the other eye is longer. In the case of presumed childhood amblyopia in one eye, vision loss in the good eye may be the only symptom of bilateral disease, which was unnoticed in the previously amblyopic eye, or a preexisting episode of LHON in the "amblyopic" eye. The clinical decision in such cases may be difficult and suggestive of other forms of atypical optic neuropathy until confirmed by genetic testing. CASE SERIES We present three genetically confirmed (MT-ND1:m.3700G>A, MT-ND6:m14484 T>C, and MT-ND4:m.11778G>A) patients with subacute vision loss in the previously good eye, with the other eye believed to be amblyopic from childhood and their features different from what would be expected in true amblyopia. In all, electrophysiology testing showed a bilaterally reduced amplitude of PERG with low VEP P100 wave amplitudes and prolonged peak time in both eyes, also unusual for amblyopia. During follow-up, the pallor of the optic discs progressed in all eyes. Significant thinning of the peripapillary retinal nerve fiber layer (pRNFL; retinal nerve fiber layer around the optic disc) and ganglion cell complex (GCC) in the macular region was present. All three patients had a peculiar history. The first patient was treated for presumed hyperopic amblyopia that did not improve since childhood, experienced visual loss in the good eye at the age of 17, and was negative for the three typical LHON mutations. Extended testing confirmed an atypical pathogenic variant MT-ND1:m.3700G>A in homoplasmy. The second patient with presumed strabismic amblyopia had an unusual presentation of vision loss only at the age of 61, and after the exclusion of other causes, a typical MT-ND4:m.11778G>A pathogenic variant was found in homoplasmy. The third case was peculiar as he had presumed strabismic amblyopia since childhood and had some degree of disc pallor in the amblyopic eye upon presenting with loss of vision in the good eye at the age of 21, and a typical pathogenic variant m14484 T>C, p.Met64Val was subsequently confirmed. However, one year after disease onset, he started to experience significant spontaneous functional improvement in the non-amblyopic up to 1.0 Snellen whilst improvement in the presumed amblyopic eye was modest, suggesting preexisting amblyopia. This interestingly extensive improvement was carefully followed by electrophysiology as well as visual acuity and fields. CONCLUSIONS This report shows three different scenarios of presentation of LHON in patients with presumed uniocular amblyopia from childhood. In such cases, the diagnosis may be difficult, and detailed structural and functional evaluation of the optic nerve head is necessary to assess whether an earlier LHON episode was misdiagnosed as amblyopia or whether LHON presented bilaterally on both eyes whilst only being noticed in the previously good eye.
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Affiliation(s)
- Sanja Petrovic Pajic
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (S.P.P.); (A.F.); (M.S.H.); (M.J.-V.)
- Clinic for Eye Diseases, University Clinical Centre of Serbia, 11000 Belgrade, Serbia
| | - Ana Fakin
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (S.P.P.); (A.F.); (M.S.H.); (M.J.-V.)
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Maja Sustar Habjan
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (S.P.P.); (A.F.); (M.S.H.); (M.J.-V.)
| | - Martina Jarc-Vidmar
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (S.P.P.); (A.F.); (M.S.H.); (M.J.-V.)
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Marko Hawlina
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (S.P.P.); (A.F.); (M.S.H.); (M.J.-V.)
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
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Abstract
Mitochondrial optic neuropathies have a leading role in the field of mitochondrial medicine ever since 1988, when the first mutation in mitochondrial DNA was associated with Leber's hereditary optic neuropathy (LHON). Autosomal dominant optic atrophy (DOA) was subsequently associated in 2000 with mutations in the nuclear DNA affecting the OPA1 gene. LHON and DOA are both characterized by selective neurodegeneration of retinal ganglion cells (RGCs) triggered by mitochondrial dysfunction. This is centered on respiratory complex I impairment in LHON and defective mitochondrial dynamics in OPA1-related DOA, leading to distinct clinical phenotypes. LHON is a subacute, rapid, severe loss of central vision involving both eyes within weeks or months, with age of onset between 15 and 35 years old. DOA is a more slowly progressive optic neuropathy, usually apparent in early childhood. LHON is characterized by marked incomplete penetrance and a clear male predilection. The introduction of next-generation sequencing has greatly expanded the genetic causes for other rare forms of mitochondrial optic neuropathies, including recessive and X-linked, further emphasizing the exquisite sensitivity of RGCs to compromised mitochondrial function. All forms of mitochondrial optic neuropathies, including LHON and DOA, can manifest either as pure optic atrophy or as a more severe multisystemic syndrome. Mitochondrial optic neuropathies are currently at the forefront of a number of therapeutic programs, including gene therapy, with idebenone being the only approved drug for a mitochondrial disorder.
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Affiliation(s)
- Valerio Carelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy; IRCCS Istituto di Scienze Neurologiche di Bologna, Programma di Neurogenetica, Bologna, Italy.
| | - Chiara La Morgia
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy; IRCCS Istituto di Scienze Neurologiche di Bologna, Programma di Neurogenetica, Bologna, Italy
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom; Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom; Institute of Ophthalmology, University College London, London, United Kingdom
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Barboni P, La Morgia C, Cascavilla ML, Hong EH, Battista M, Majander A, Caporali L, Starace V, Amore G, Renzo AD, Carbonelli M, Nucci P, Jurkute N, Chen BS, Panebianco R, De Negri AM, Sadun F, Parisi V, Bandello F, Sadun AA, Carelli V, Yu-Wai-Man P. Childhood-Onset Leber Hereditary Optic Neuropathy-Clinical and Prognostic Insights. Am J Ophthalmol 2022; 249:99-107. [PMID: 36543315 DOI: 10.1016/j.ajo.2022.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022]
Abstract
PURPOSE To investigate the clinical and molecular genetic features of childhood-onset Leber hereditary optic neuropathy (LHON) to gain a better understanding of the factors influencing the visual outcome in this atypical form of the disease. DESIGN Retrospective cohort study. METHODS We retrospectively included 2 cohorts of patients with LHON with onset of visual loss before the age of 12 years from Italy and the United Kingdom. Ophthalmologic evaluation, including best-corrected visual acuity, orthoptic evaluation, slit-lamp biomicroscopy, visual field testing, and optical coherence tomography, was considered. Patients were classified based on both the age of onset and the pattern of visual loss. RESULTS A total of 68 patients were stratified based on the age of onset of visual loss: group 1 (<3 years): 14 patients (20.6%); group 2 (≥3 to <9 years): 27 patients (39.7%); and group 3 (≥9 to ≤12 years): 27 patients (39.7%). Patients in group 2 achieved a better visual outcome than those in group 3. Patients in groups 1 and 2 had better mean deviation on visual field testing than those in group 3. The mean ganglion cell layer thickness on optical coherence tomography in group 2 was higher than those in groups 1 and 3. Patients were also categorized based on the pattern of visual loss as follows: Subacute Bilateral: 54 patients (66.7%); Insidious Bilateral: 14 patients (17.3%); Unilateral: 9 patients (11.1%); and Subclinical Bilateral: 4 patients (4.9%). CONCLUSIONS Children who lose vision from LHON before the age of 9 years have a better visual prognosis than those who become affected in later years, likely representing a "form frustre" of the disease.
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Affiliation(s)
- Piero Barboni
- From the Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan (P.B., M.L.C., M.B., V.S., F.B.); Department of ophthalmology, Studio Oculistico d'Azeglio (P.B., M.C.).
| | - Chiara La Morgia
- Department of ophthalmology, IRCCS Istituto delle Scienze Neurologiche di Bologna, (C.L.M., L.C., V.C.) Bologna, Italy
| | - Maria Lucia Cascavilla
- From the Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan (P.B., M.L.C., M.B., V.S., F.B.)
| | - Eun Hee Hong
- Moorfields Eye Hospital, London, United Kingdom (E.H.H., A.M., N.J., P.Y-W-M.); Department of Ophthalmology, Hanyang University College of Medicine, Seoul, Korea (E.H.H.)
| | - Marco Battista
- From the Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan (P.B., M.L.C., M.B., V.S., F.B.)
| | - Anna Majander
- Moorfields Eye Hospital, London, United Kingdom (E.H.H., A.M., N.J., P.Y-W-M.); UCL Institute of Ophthalmology, University College London, London, United Kingdom (A.M., N.J., P.Y-W-M.); Department of Ophthalmology, Helsinki University Hospital, and University of Helsinki, Helsinki, Finland (A.M.)
| | - Leonardo Caporali
- Department of ophthalmology, IRCCS Istituto delle Scienze Neurologiche di Bologna, (C.L.M., L.C., V.C.) Bologna, Italy
| | - Vincenzo Starace
- From the Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan (P.B., M.L.C., M.B., V.S., F.B.)
| | - Giulia Amore
- Unit of Neurology, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna (G.A., M.C., V.C.)
| | | | - Michele Carbonelli
- Department of ophthalmology, Studio Oculistico d'Azeglio (P.B., M.C.); Unit of Neurology, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna (G.A., M.C., V.C.)
| | - Paolo Nucci
- Department of Clinical Science and Community Health, University of Milan, Milan, (P.N.), Italy
| | - Neringa Jurkute
- Moorfields Eye Hospital, London, United Kingdom (E.H.H., A.M., N.J., P.Y-W-M.); UCL Institute of Ophthalmology, University College London, London, United Kingdom (A.M., N.J., P.Y-W-M.)
| | - Benson S Chen
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge (B.S.C., P.Y-W-M.); Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, (B.S.C., P.Y-W-M.), Cambridge, United Kingdom
| | | | | | | | - Vincenzo Parisi
- IRCCS G.B. Bietti Foundation I.R.C.C.S., Rome (A.D.R., V.P.)
| | - Francesco Bandello
- From the Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan (P.B., M.L.C., M.B., V.S., F.B.)
| | - Alfredo A Sadun
- and Doheny Eye Institute/UCLA School of Medicine, Los Angeles, California, USA (A.A.S)
| | - Valerio Carelli
- Department of ophthalmology, IRCCS Istituto delle Scienze Neurologiche di Bologna, (C.L.M., L.C., V.C.) Bologna, Italy; Unit of Neurology, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna (G.A., M.C., V.C.)
| | - Patrick Yu-Wai-Man
- Moorfields Eye Hospital, London, United Kingdom (E.H.H., A.M., N.J., P.Y-W-M.); UCL Institute of Ophthalmology, University College London, London, United Kingdom (A.M., N.J., P.Y-W-M.); Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge (B.S.C., P.Y-W-M.); Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, (B.S.C., P.Y-W-M.), Cambridge, United Kingdom
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Ahn YJ, Park Y, Shin SY, Chae H, Kim M, Park SH. Genotypic and phenotypic characteristics of Korean children with childhood-onset Leber's hereditary optic neuropathy. Graefes Arch Clin Exp Ophthalmol 2020; 258:2283-2290. [PMID: 32506279 DOI: 10.1007/s00417-020-04757-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 05/11/2020] [Accepted: 05/19/2020] [Indexed: 10/24/2022] Open
Abstract
PURPOSE We sought to identify the phenotypic and genotypic characteristics of Korean children with genetically confirmed Leber's hereditary optic neuropathy (LHON). METHODS The medical records of 64 genetically confirmed LHON patients were reviewed. Seventeen patients aged 13 years or younger with optic atrophy with positive mitochondrial DNA (mtDNA) mutations were considered to demonstrate childhood-onset LHON. The non-childhood-onset group included 47 patients with genetically confirmed LHON who experienced disease onset later than 13 years of age. The type of mtDNA mutation, visual acuity (VA), color vision, fundus photography, retinal nerve fiber layer (RNFL) thickness, and visual field were investigated. RESULTS Sequence analysis of the mitochondrial genome revealed five different kinds of LHON-associated mtDNA mutations among our childhood-onset patients, including m.11778G>A (58.8%), m.3496G>T (11.8%), m.3497C>T (5.9%), m.11696G>A (5.9%), and m.14502T>C (5.9%). The mean final best-corrected VA in the childhood-onset group was better than that in the non-childhood-onset group with the value of logMAR 0.29 (0.09-0.75) vs. 0.55 (0.27-1.29) (expressed as median (interquartile range); p = 0.05). Spontaneous visual recovery was observed in 35.3% of the childhood-onset group but in only 12.8% of the non-childhood-onset group (p = 0.04). Eight patients (47.1%) showed interocular asymmetry of the disease, with two presenting true unilateral involvement of the optic nerve and the other six patients demonstrating unilateral subclinical manifestations with bilateral optic atrophy. CONCLUSION Involvement of secondary mitochondrial mutations was confirmed in patients with childhood-onset LHON. Characteristic clinical features of childhood-onset LHON included a higher proportion of subacute or insidious onset of symptoms, better VA, higher spontaneous recovery, and asymmetrical ocular involvement.
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Affiliation(s)
- Ye Jin Ahn
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea
| | - Yooyeon Park
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea
| | - Sun Young Shin
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea
| | - Hyojin Chae
- Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Myungshin Kim
- Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Shin Hae Park
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea.
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Littlewood R, Mollan SP, Pepper IM, Hickman SJ. The Utility of Fundus Fluorescein Angiography in Neuro-Ophthalmology. Neuroophthalmology 2019; 43:217-234. [PMID: 31528186 DOI: 10.1080/01658107.2019.1604764] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 04/04/2019] [Accepted: 04/04/2019] [Indexed: 10/26/2022] Open
Abstract
While its use is still widespread within the medical retina field, fundus fluorescein angiography (FFA) is increasingly falling out of favour in the investigation of neuro-ophthalmological disease, with the introduction of new technologies, particularly optical coherence tomography. FFA does, however, provide useful diagnostic and prognostic information in many neuro-ophthalmological diseases including papilloedema, pseudo-papilloedema, optic neuropathies and central retinal artery occlusion to name a few. We aim to summarise the main FFA findings in each of these conditions and highlight where FFA is of most use in providing complementary information to other modes of investigation.
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Affiliation(s)
| | - Susan P Mollan
- Department of Ophthalmology, Queen Elizabeth Hospital, Birmingham, UK
| | - Irene M Pepper
- Department of Ophthalmology, Royal Hallamshire Hospital, Sheffield, UK
| | - Simon J Hickman
- Department of Neurology, Royal Hallamshire Hospital, Sheffield, UK
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Kousal B, Kolarova H, Meliska M, Bydzovsky J, Diblik P, Kulhanek J, Votruba M, Honzik T, Liskova P. Peripapillary microcirculation in Leber hereditary optic neuropathy. Acta Ophthalmol 2019; 97:e71-e76. [PMID: 30259673 DOI: 10.1111/aos.13817] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 04/13/2018] [Indexed: 12/28/2022]
Abstract
PURPOSE In this prospective observational comparative case series, we aimed to study the peripapillary capillary network with spectral-domain optical coherence tomography angiography (OCT-A) in Leber hereditary optic neuropathy (LHON). METHODS Twelve eyes of six individuals, of these three males (five eyes) after clinical onset of visual impairment were imaged by OCT-A with scans centred on optic discs. Control group consisted of 6 eyes with no visual impairment. RESULTS The three affected individuals lost vision 6 years (at age 22 years), 2 years and 3 months (at age 26 years) and 1 year and 2 months (at age 30 years) prior to OCT-A examination. All five affected eyes had alterations in density of the radial peripapillary microvascular network at the level of retinal nerve fibre layer, including an eye of a patient treated with idebenone that underwent almost full recovery (best corrected visual acuity 0.87). Interestingly, the other eye showed normal ocular findings 14 months after onset. Results of OCT-A examination in this eye were unfortunately inconclusive due to a delineation error. At the level of the ganglion cell layer differences could be also noted, but only in two severely affected individuals. There were no differences between unaffected mutation carriers and control eyes. CONCLUSION Optical coherence tomography angiography scans confirmed that the peripapillary microvascular network is highly abnormal in eyes manifesting visual impairment due to LHON. These findings support the hypothesis that microangiopathy contributes to the development of vision loss in this mitochondrial disorder.
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Affiliation(s)
- Bohdan Kousal
- Department of Ophthalmology; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
- Department of Paediatrics and Adolescent Medicine; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Hana Kolarova
- Department of Paediatrics and Adolescent Medicine; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Martin Meliska
- Department of Ophthalmology; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Jan Bydzovsky
- Department of Ophthalmology; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Pavel Diblik
- Department of Ophthalmology; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Jan Kulhanek
- Department of Paediatrics and Adolescent Medicine; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Marcela Votruba
- School of Optometry & Vision Sciences; Cardiff University; Cardiff UK
- Cardiff Eye Unit; University Hospital of Wales; Cardiff UK
| | - Tomas Honzik
- Department of Paediatrics and Adolescent Medicine; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
| | - Petra Liskova
- Department of Ophthalmology; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
- Department of Paediatrics and Adolescent Medicine; First Faculty of Medicine; Charles University and General University Hospital in Prague; Prague Czech Republic
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Abstract
A 5-year-old boy developed profound loss of vision in his right eye and was found to have a 11778 mitochondrial point mutation consistent with Leber hereditary optic neuropathy (LHON). He maintained 20/20 vision in the left eye for 18 years until age 23, when he experienced loss of vision in that eye. This 18 year interval between eye involvement in LHON is the longest reported to date and reinforces the variability in presentation and progression seen in this disease.
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Lateral thinking - Interocular symmetry and asymmetry in neurovascular patterning, in health and disease. Prog Retin Eye Res 2017; 59:131-157. [PMID: 28457789 DOI: 10.1016/j.preteyeres.2017.04.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/24/2017] [Accepted: 04/24/2017] [Indexed: 02/07/2023]
Abstract
No biological system or structure is likely to be perfectly symmetrical, or have identical right and left forms. This review explores the evidence for eye and visual pathway asymmetry, in health and in disease, and attempts to provide guidance for those studying the structure and function of the visual system, where recognition of symmetry or asymmetry may be essential. The principal question with regards to asymmetry is not 'are the eyes the same?', for some degree of asymmetry is pervasive, but 'when are they importantly different?'. Knowing if right and left eyes are 'importantly different' could have significant consequences for deciding whether right or left eyes are included in an analysis or for examining the association between a phenotype and ocular parameter. The presence of significant asymmetry would also have important implications for the design of normative databases of retinal and optic nerve metrics. In this review, we highlight not only the universal presence of asymmetry, but provide evidence that some elements of the visual system are inherently more asymmetric than others, pointing to the need for improved normative data to explain sources of asymmetry and their impact on determining associations with genetic, environmental or health-related factors and ultimately in clinical practice.
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Finsterer J, Zarrouk-Mahjoub S. Mitochondrial vasculopathy. World J Cardiol 2016; 8:333-339. [PMID: 27231520 PMCID: PMC4877362 DOI: 10.4330/wjc.v8.i5.333] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 01/16/2016] [Accepted: 03/14/2016] [Indexed: 02/06/2023] Open
Abstract
Mitochondrial disorders (MIDs) are usually multisystem disorders (mitochondrial multiorgan disorder syndrome) either on from onset or starting at a point during the disease course. Most frequently affected tissues are those with a high oxygen demand such as the central nervous system, the muscle, endocrine glands, or the myocardium. Recently, it has been shown that rarely also the arteries may be affected (mitochondrial arteriopathy). This review focuses on the type, diagnosis, and treatment of mitochondrial vasculopathy in MID patients. A literature search using appropriate search terms was carried out. Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy. Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy, migraine-like headache, stroke-like episodes, or peripheral retinopathy. Mitochondrial macroangiopathy manifests as atherosclerosis, ectasia of arteries, aneurysm formation, dissection, or spontaneous rupture of arteries. The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes. Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes. Mitochondrial vasculopathy exists and manifests as micro- or macroangiopathy. Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications.
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Thouin A, Griffiths PG, Hudson G, Chinnery PF, Yu-Wai-Man P. Raised intraocular pressure as a potential risk factor for visual loss in Leber Hereditary Optic Neuropathy. PLoS One 2013; 8:e63446. [PMID: 23667621 PMCID: PMC3646743 DOI: 10.1371/journal.pone.0063446] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 04/03/2013] [Indexed: 01/22/2023] Open
Abstract
Leber Hereditary Optic Neuropathy (LHON) is an important cause of inherited mitochondrial blindness among young adults. The majority of patients carry one of three mitochondrial DNA (mtDNA) point mutations: m.3460G>A, m.11778G>A and m.14484T>C, all of which affect critical complex I subunits of the mitochondrial respiratory chain. LHON is characterised by marked incomplete penetrance, clearly implying that the mtDNA mutation is insufficient on its own to trigger retinal ganglion cell dysfunction and visual loss. In this case series of three affected patients harbouring the m.11778G>A mutation, we provide evidence suggesting that raised intraocular pressure could be a risk factor triggering visual loss in at-risk LHON carriers.
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Affiliation(s)
- Anais Thouin
- Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Philip G. Griffiths
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
| | - Gavin Hudson
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Patrick F. Chinnery
- Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Patrick Yu-Wai-Man
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
- * E-mail:
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Finsterer J, Mahjoub SZ. Primary mitochondrial arteriopathy. Nutr Metab Cardiovasc Dis 2012; 22:393-399. [PMID: 22520486 DOI: 10.1016/j.numecd.2012.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 12/27/2011] [Accepted: 01/05/2012] [Indexed: 12/28/2022]
Abstract
AIM Whether arteries are affected in mitochondrial disorders (MIDs) was under debate for years but meanwhile there are strong indications that large and small arteries are primarily or secondarily affected in MIDs. DATA SYNTHESIS When reviewing the literature for appropriate studies it turned out that vascular involvement in MIDs includes primary or secondary micro- or macroangiopathy of the cerebral, cervical, and retinal arteries, the aorta, the iliac arteries, the brachial arteries, or the muscular arteries. Arteriopathy in MIDs manifests as atherosclerosis, stenosis, occlusion, dissection, ectasia, aneurysm formation, or arteriovenous malformation. Direct evidence for primary cerebral microangiopathy comes from histological studies and indirect evidence from imaging and perfusion studies of the brain. Microangiopathy of the retina is highly prevalent in Leber's hereditary optic neuropathy. Macroangiopathy of the carotid arteries may be complicated by stroke. Arteriopathy of the aorta may result in ectasia, aneurysm formation, or even rupture. Further evidence for arteriopathy in MIDs comes from the frequent association of migraine with MIDs and the occurrence of premature atherosclerosis in MID patients without classical risk factors. CONCLUSIONS Mitochondrial arteriopathy most frequently concerns the cerebral arteries and may result from the underlying metabolic defect or secondary from associated vascular risk factors. Vascular involvement in MIDs has a strong impact on the prognosis and outcome of these patients.
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Affiliation(s)
- J Finsterer
- Danube University Krems, Krems, Postfach 20, 1180 Vienna, Austria.
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Yu-Wai-Man P, Griffiths PG, Chinnery PF. Mitochondrial optic neuropathies - disease mechanisms and therapeutic strategies. Prog Retin Eye Res 2011; 30:81-114. [PMID: 21112411 PMCID: PMC3081075 DOI: 10.1016/j.preteyeres.2010.11.002] [Citation(s) in RCA: 440] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Leber hereditary optic neuropathy (LHON) and autosomal-dominant optic atrophy (DOA) are the two most common inherited optic neuropathies in the general population. Both disorders share striking pathological similarities, marked by the selective loss of retinal ganglion cells (RGCs) and the early involvement of the papillomacular bundle. Three mitochondrial DNA (mtDNA) point mutations; m.3460G>A, m.11778G>A, and m.14484T>C account for over 90% of LHON cases, and in DOA, the majority of affected families harbour mutations in the OPA1 gene, which codes for a mitochondrial inner membrane protein. Optic nerve degeneration in LHON and DOA is therefore due to disturbed mitochondrial function and a predominantly complex I respiratory chain defect has been identified using both in vitro and in vivo biochemical assays. However, the trigger for RGC loss is much more complex than a simple bioenergetic crisis and other important disease mechanisms have emerged relating to mitochondrial network dynamics, mtDNA maintenance, axonal transport, and the involvement of the cytoskeleton in maintaining a differential mitochondrial gradient at sites such as the lamina cribosa. The downstream consequences of these mitochondrial disturbances are likely to be influenced by the local cellular milieu. The vulnerability of RGCs in LHON and DOA could derive not only from tissue-specific, genetically-determined biological factors, but also from an increased susceptibility to exogenous influences such as light exposure, smoking, and pharmacological agents with putative mitochondrial toxic effects. Our concept of inherited mitochondrial optic neuropathies has evolved over the past decade, with the observation that patients with LHON and DOA can manifest a much broader phenotypic spectrum than pure optic nerve involvement. Interestingly, these phenotypes are sometimes clinically indistinguishable from other neurodegenerative disorders such as Charcot-Marie-Tooth disease, hereditary spastic paraplegia, and multiple sclerosis, where mitochondrial dysfunction is also thought to be an important pathophysiological player. A number of vertebrate and invertebrate disease models has recently been established to circumvent the lack of human tissues, and these have already provided considerable insight by allowing direct RGC experimentation. The ultimate goal is to translate these research advances into clinical practice and new treatment strategies are currently being investigated to improve the visual prognosis for patients with mitochondrial optic neuropathies.
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MESH Headings
- Animals
- DNA, Mitochondrial/genetics
- Disease Models, Animal
- Humans
- Optic Atrophy, Autosomal Dominant/pathology
- Optic Atrophy, Autosomal Dominant/physiopathology
- Optic Atrophy, Autosomal Dominant/therapy
- Optic Atrophy, Hereditary, Leber/pathology
- Optic Atrophy, Hereditary, Leber/physiopathology
- Optic Atrophy, Hereditary, Leber/therapy
- Optic Nerve/pathology
- Phenotype
- Point Mutation
- Retinal Ganglion Cells/pathology
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Affiliation(s)
- Patrick Yu-Wai-Man
- Mitochondrial Research Group, Institute for Ageing and Health, The Medical School, Newcastle University, UK.
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Abstract
Hereditary optic neuropathies are caused by mutations either in the nuclear or mitochondrial genome and lead to retinal ganglion cell death mediated by reduced oxidative phosphorylation, fragmentation of the mitochondrial network, and increased sensitivity to apoptosis. Nuclear mutations result in autosomal dominant optic atrophy, autosomal recessive optic atrophy, or X-linked recessive optic atrophy, whereas mitochondrial mutations result in Leber's hereditary optic neuropathy, which is maternally inherited. A tentative diagnosis of a hereditary optic neuropathy can usually be made on the grounds of a thorough patient and family history, visual field and color vision tests, and a detailed assessment of the optic nerve head. The rarity of hereditary optic neuropathies makes it difficult to include these disorders in the differential diagnosis. Molecular genetic testing of a blood DNA sample should be performed on every patient, with implications for future genetic counseling and prediction of the disease course.
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Aggarwal D, Carelli V, Sadun AA. Genotype–phenotype correlations in mitochondrial optic neuropathies. EXPERT REVIEW OF OPHTHALMOLOGY 2009. [DOI: 10.1586/eop.09.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Yu-Wai-Man P, Griffiths PG, Hudson G, Chinnery PF. Inherited mitochondrial optic neuropathies. J Med Genet 2009; 46:145-58. [PMID: 19001017 PMCID: PMC2643051 DOI: 10.1136/jmg.2007.054270] [Citation(s) in RCA: 287] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 09/08/2008] [Accepted: 10/07/2008] [Indexed: 02/02/2023]
Abstract
Leber hereditary optic neuropathy (LHON) and autosomal dominant optic atrophy (DOA) are the two most common inherited optic neuropathies and they result in significant visual morbidity among young adults. Both disorders are the result of mitochondrial dysfunction: LHON from primary mitochondrial DNA (mtDNA) mutations affecting the respiratory chain complexes; and the majority of DOA families have mutations in the OPA1 gene, which codes for an inner mitochondrial membrane protein critical for mtDNA maintenance and oxidative phosphorylation. Additional genetic and environmental factors modulate the penetrance of LHON, and the same is likely to be the case for DOA which has a markedly variable clinical phenotype. The selective vulnerability of retinal ganglion cells (RGCs) is a key pathological feature and understanding the fundamental mechanisms that underlie RGC loss in these disorders is a prerequisite for the development of effective therapeutic strategies which are currently limited.
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MESH Headings
- DNA, Mitochondrial
- Female
- GTP Phosphohydrolases/genetics
- Humans
- Male
- Optic Atrophy, Autosomal Dominant/diagnosis
- Optic Atrophy, Autosomal Dominant/epidemiology
- Optic Atrophy, Autosomal Dominant/genetics
- Optic Atrophy, Autosomal Dominant/pathology
- Optic Atrophy, Hereditary, Leber/diagnosis
- Optic Atrophy, Hereditary, Leber/epidemiology
- Optic Atrophy, Hereditary, Leber/genetics
- Optic Atrophy, Hereditary, Leber/pathology
- Point Mutation
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Affiliation(s)
- P Yu-Wai-Man
- Mitochondrial Research Group, The Medical School, Newcastle University, Newcastle upon Tyne, UK
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - P G Griffiths
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - G Hudson
- Mitochondrial Research Group, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - P F Chinnery
- Mitochondrial Research Group, The Medical School, Newcastle University, Newcastle upon Tyne, UK
- Institute of Human Genetics, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
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