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Mack HG, Milea D, Thyagarajan D, Fagan X. Reply: Stroke-like episode of the optic nerve. Can J Ophthalmol 2024; 59:e78. [PMID: 38280822 DOI: 10.1016/j.jcjo.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2024]
Affiliation(s)
- Heather G Mack
- Melbourne Medical School, University of Melbourne, Melbourne, Australia; Melbourne Health, Melbourne, Australia; Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Dan Milea
- Singapore National Eye Centre, Singapore Eye Research Institute and Duke-NUS, Singapore
| | | | - Xavier Fagan
- Centre for Eye Research Australia, Melbourne, Australia; Royal Victorian Eye and Ear Hospital, Melbourne, Australia
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2
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Siejka TP, Bertram KL, Tang HM, Thyagarajan D, O’Brien TJ, Butzkueven H, Vivash L, Harding IH. Monash-Alfred protocol for assessment of atypical parkinsonian syndromes (MAP-APS). BMJ Neurol Open 2024; 6:e000553. [PMID: 38268757 PMCID: PMC10806876 DOI: 10.1136/bmjno-2023-000553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 11/12/2023] [Indexed: 01/26/2024] Open
Abstract
Introduction Atypical parkinsonian syndromes (APS) are rare neurodegenerative syndromes for which parkinsonism is one significant feature. APS includes progressive supranuclear palsy (PSP), multiple system atrophy (MSA) and corticobasal syndrome (CBS). The diagnosis of APS remains reliant on clinical features with no available diagnostic or prognostic biomarker. Clinical scales remain the gold standard assessment measures in clinical trials and research. The lack of standardised approach for research cohorts has contributed to shortcomings in disease understanding and limits collaboration between researchers. The primary objectives of this study are to (1) establish an assessment protocol for parkinsonian syndromes and (2) to implement it at a single site to establish the viability and utility of populating a clinical and biological databank of patients with APS. Methods The Monash Alfred Protocol for Assessment of APS was devised by expert consensus within a broad multidisciplinary team. Eligible patients are diagnosed as possible or probable PSP, MSA or CBS by a consultant neurologist with expertise in movement disorders. Participants will be assessed at recruitment and then annually for up to 3 years; individuals within 5 years of index symptom onset will also undergo a once-off 6-month assessment. Ethics and dissemination Each participant or their legally authorised representative will provide informed written consent prior to commencement of the study. Data will be stored on a locally hosted Research Electronic Data Capture database. Trial registration number Australian New Zealand Clinical Trials Registry (ANZCTN 12622000923763).
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Affiliation(s)
- Timothy P Siejka
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Kelly L Bertram
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Huiliang M Tang
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Dominic Thyagarajan
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Terence J O’Brien
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Helmut Butzkueven
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Lucy Vivash
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
| | - Ian H Harding
- Monash University Central Clinical School, Melbourne, Victoria, Australia
- Alfred Health Neurology, Melbourne, Victoria, Australia
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3
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Permezel F, Alty J, Harding IH, Thyagarajan D. Brain Networks Involved in Sensory Perception in Parkinson's Disease: A Scoping Review. Brain Sci 2023; 13:1552. [PMID: 38002513 PMCID: PMC10669548 DOI: 10.3390/brainsci13111552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 10/26/2023] [Accepted: 10/31/2023] [Indexed: 11/26/2023] Open
Abstract
Parkinson's Disease (PD) has historically been considered a disorder of motor dysfunction. However, a growing number of studies have demonstrated sensory abnormalities in PD across the modalities of proprioceptive, tactile, visual, auditory and temporal perception. A better understanding of these may inform future drug and neuromodulation therapy. We analysed these studies using a scoping review. In total, 101 studies comprising 2853 human participants (88 studies) and 125 animals (13 studies), published between 1982 and 2022, were included. These highlighted the importance of the basal ganglia in sensory perception across all modalities, with an additional role for the integration of multiple simultaneous sensation types. Numerous studies concluded that sensory abnormalities in PD result from increased noise in the basal ganglia and increased neuronal receptive field size. There is evidence that sensory changes in PD and impaired sensorimotor integration may contribute to motor abnormalities.
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Affiliation(s)
- Fiona Permezel
- Department of Neuroscience, Monash University, Melbourne 3004, Australia; (F.P.); (I.H.H.)
- Department of Neurology, Mayo Clinic, Rochester, MN 55901, USA
| | - Jane Alty
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart 7001, Australia;
| | - Ian H. Harding
- Department of Neuroscience, Monash University, Melbourne 3004, Australia; (F.P.); (I.H.H.)
| | - Dominic Thyagarajan
- Department of Neuroscience, Monash University, Melbourne 3004, Australia; (F.P.); (I.H.H.)
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4
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Ma A, Desai N, Lau KK, Palaniswami M, O'Brien TJ, Palaniswami P, Thyagarajan D. Automated measurement of inter-arytenoid distance on 4D laryngeal CT: A validation study. PLoS One 2023; 18:e0279927. [PMID: 36652423 PMCID: PMC9847963 DOI: 10.1371/journal.pone.0279927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 12/16/2022] [Indexed: 01/19/2023] Open
Abstract
Changes to the voice are prevalent and occur early in Parkinson's disease. Correlates of these voice changes on four-dimensional laryngeal computed-tomography imaging, such as the inter-arytenoid distance, are promising biomarkers of the disease's presence and severity. However, manual measurement of the inter-arytenoid distance is a laborious process, limiting its feasibility in large-scale research and clinical settings. Automated methods of measurement provide a solution. Here, we present a machine-learning module which determines the inter-arytenoid distance in an automated manner. We obtained automated inter-arytenoid distance readings on imaging from participants with Parkinson's disease as well as healthy controls, and then validated these against manually derived estimates. On a modified Bland-Altman analysis, we found a mean bias of 1.52 mm (95% limits of agreement -1.7 to 4.7 mm) between the automated and manual techniques, which improves to a mean bias of 0.52 mm (95% limits of agreement -1.9 to 2.9 mm) when variability due to differences in slice selection between the automated and manual methods are removed. Our results demonstrate that estimates of the inter-arytenoid distance with our automated machine-learning module are accurate, and represents a promising tool to be utilized in future work studying the laryngeal changes in Parkinson's disease.
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Affiliation(s)
- Andrew Ma
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
- Department of Neurology, Monash Health, Melbourne, Victoria, Australia
| | - Nandakishor Desai
- Department of Electrical and Electronic Engineering, The University of Melbourne, Melbourne, Victoria, Australia
| | - Kenneth K Lau
- School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Monash Health Imaging, Monash Health, Melbourne, Victoria, Australia
| | - Marimuthu Palaniswami
- Department of Electrical and Electronic Engineering, The University of Melbourne, Melbourne, Victoria, Australia
| | - Terence J O'Brien
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
| | - Paari Palaniswami
- School of Computing and Information Systems, Faculty of Engineering and Information Technology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Dominic Thyagarajan
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
- Department of Neurology, Monash Health, Melbourne, Victoria, Australia
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5
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Zhang L, Thyagarajan D. Two Rare Cases of Long Surviving Riboflavin Transporter Deficiency with Co-Existing Adenosine Monophosphate Deaminase (AMP) Deficiency. Brain Sci 2022; 12:brainsci12121605. [PMID: 36552065 PMCID: PMC9775375 DOI: 10.3390/brainsci12121605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 11/19/2022] [Accepted: 11/22/2022] [Indexed: 11/24/2022] Open
Abstract
(1) Background: Riboflavin transporter deficiency (RTD), formerly known as Brown−Vialetto−Van Laere syndrome, is a rare condition that causes a progressive neurological syndrome in early life with features of auditory and optic neuropathy, weakness of bulbar muscles and the diaphragm and sensorimotor neuropathy. Pathologic mutations in the genes that code for riboflavin transporters have been identified as the genetic basis of RTD, and the majority of the genetically confirmed cases are caused by mutations of SLC52A3, a riboflavin transporter 2 coding gene or compound mutations in SLC52A2, encoding riboflavin transporter 3. Fatality in childhood is common if the condition is left untreated, but survival into adulthood has been reported in cases treated with high-dose oral riboflavin. (2) Case summary: We report two long-term survivors of RTD type 2 due to compound heterozygous 185T> G and 1258G>A mutations in gene SLC2A2. They are two brothers in a family in which two female siblings died in childhood from a similar neurological disorder. Brother one, the older RTD survivor, is aged 71, and brother two is aged 58. Both have significant visual impairment from optic nerve atrophy and sensory ataxia. Their muscle biopsies showed decreased muscle adenosine monophosphate (AMP) deaminase activity. No AMPD1 mutation was detected through whole-genome sequencing. (3) Conclusion: Co-existing riboflavin transporter deficiency (RTD) type 2 and muscle AMP deaminase deficiency has not been previously reported. Apart from the possibility that there is a milder phenotype associated with these mutations in SLC2A2, AMP deaminase deficiency might have contributed to a survival benefit by preserving muscle function through accumulating intracellular AMP.
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Affiliation(s)
- Lin Zhang
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Neuroscience, Eastern Health, VIC 3128, Australia
- Correspondence:
| | - Dominic Thyagarajan
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Neuroscience, The Alfred Health, Melbourne, VIC 3004, Australia
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6
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Ma A, Lau KK, Thyagarajan D. Radiological correlates of vocal fold bowing as markers of Parkinson's disease progression: A cross-sectional study utilizing dynamic laryngeal CT. PLoS One 2021; 16:e0258786. [PMID: 34653231 PMCID: PMC8519464 DOI: 10.1371/journal.pone.0258786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 10/05/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To determine whether arytenoid cartilage position and dynamics change with advancing duration and severity (as graded by MDS-UPDRS part III scores) in Parkinson's disease, in a cross-sectional study design, we performed laryngeal four-dimensional computed tomography (4D-CT) in people with Parkinson's disease and controls. METHODS 31 people with Parkinson's disease covering a range of disease duration and severity and 19 controls underwent laryngeal 4D-CT whilst repeatedly vocalizing. We measured on each CT volume the glottic area (GA), inter-arytenoid distance (IAD), IAD-Area index (IAI) and arytenoid cartilage velocity ([Formula: see text]). RESULTS People with Parkinson's disease had reductions in the mean/effective minimum IAD when compared to controls, while mean/effective minimum GA and mean/effective maximum IAI were increased. Arytenoid cartilage velocities showed no difference. On Spearman correlation analyses, advancing disease duration and severity of PD showed moderately strong and significant correlations with increasing mean/effective minimum GA, increasing mean/effective maximum IAI and decreasing effective minimum IAD. Linear mixed models which considered the effects of intra and inter-individual variation showed that both disease duration (b = -0.011, SEb = 0.053, 95% CI [-0.022, 0], t(27) = -2.10, p = 0.045) and severity (b = -0.069, SEb = 0.032, 95% CI [-0.14,-0.0039], t(27) = -2.17, p = 0.039) were significant predictors for IAD, and also for transformed values of the GA and IAI. CONCLUSIONS There are progressive alterations in phonatory posturing as Parkinson's disease advances. The increases in GA despite reductions in IAD are concordant with prior observations of vocal fold bowing. Our study provides a basis for using laryngeal 4D-CT to assess disease progression in Parkinson's disease.
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Affiliation(s)
- Andrew Ma
- Department of Neurosciences, Central Clinical School, Monash University, Melbourne, Australia
- Department of Neurology, Monash Health, Melbourne, Australia
- Department of Neurology, Alfred Health, Melbourne, Australia
| | - Kenneth K. Lau
- School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia
- Monash Health Imaging, Monash Health, Melbourne, Australia
| | - Dominic Thyagarajan
- Department of Neurosciences, Central Clinical School, Monash University, Melbourne, Australia
- Department of Neurology, Monash Health, Melbourne, Australia
- Department of Neurology, Alfred Health, Melbourne, Australia
- * E-mail:
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Sue CM, Balasubramaniam S, Bratkovic D, Bonifant C, Christodoulou J, Coman D, Crawley K, Edema-Hildebrand F, Ellaway C, Ghaoui R, Kearns LS, Lee J, Liang C, Mackey DA, Murray S, Needham M, Ruis R, Russell J, Thyagarajan D, Wools C. Patient Care Standards for Primary Mitochondrial Disease in Australia. An Australian adaptation of the Mitochondrial Medicine Society recommendations. Intern Med J 2021; 52:110-120. [PMID: 34505344 PMCID: PMC9299181 DOI: 10.1111/imj.15505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 08/16/2021] [Accepted: 08/21/2021] [Indexed: 11/28/2022]
Abstract
This document provides consensus‐based recommendations for general physicians and primary care physicians who diagnose and manage patients with mitochondrial diseases (MD). It builds on previous international guidelines, with particular emphasis on clinical management in the Australian setting. This statement was prepared by a working group of medical practitioners, nurses and allied health professionals with clinical expertise and experience in managing Australian patients with MD. As new treatments and management plans emerge, these consensus‐based recommendations will continue to evolve, but current standards of care are summarised in this document.
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Affiliation(s)
- Carolyn M Sue
- Department of Neurology, Royal North Shore Hospital, Sydney, New South Wales, Australia.,Department of Neurogenetics, Kolling Institute, University of Sydney, Sydney, New South Wales, Australia
| | - Shanti Balasubramaniam
- Genetic Metabolic Disorders Service, The Children's Hospital at Westmead, Sydney Children's Hospital Network, Sydney, New South Wales, Australia.,Disciplines of Child and Adolescent Health and Genetic Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Drago Bratkovic
- Metabolic Clinic, Women's and Children's Hospital, Adelaide, South Australia, Australia
| | - Catherine Bonifant
- Department of Dietetics and Food Services, Queensland Children's Hospital, Brisbane, Queensland, Australia
| | - John Christodoulou
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria.,Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, New South UK.,Discipline of Child and Adolescent Health, University of Sydney, Sydney, New South UK
| | - David Coman
- Department of Metabolic Medicine, Queensland Children's Hospital, Brisbane, Queensland, Australia.,School of Medicine, University of Queensland, Brisbane, Queensland, Australia.,School of Medicine, Griffith University, Mt Gravatt, Queensland, Australia
| | - Karen Crawley
- Department of Neurogenetics, Kolling Institute, University of Sydney, Sydney, New South Wales, Australia
| | | | - Carolyn Ellaway
- Disciplines of Child and Adolescent Health and Genetic Medicine, University of Sydney, Sydney, New South Wales, Australia.,Genetic Metabolic Disorders Service Sydney Children's Hospital Network, Sydney, New South Wales, Australia
| | - Roula Ghaoui
- Department of Neurology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Lisa S Kearns
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria
| | - Joy Lee
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria.,Department of Metabolic Medicine, Royal Children's Hospital, Melbourne, Victoria
| | - Christina Liang
- Department of Neurology, Royal North Shore Hospital, Sydney, New South Wales, Australia.,Department of Neurogenetics, Kolling Institute, University of Sydney, Sydney, New South Wales, Australia
| | - David A Mackey
- Centre for Ophthalmology and Visual Science, University of Western Australia, Lions Eye Institute, Perth, Western Australia
| | | | - Merrilee Needham
- Notre Dame University, Fremantle, Western Australia.,IIID Murdoch University, Perth, Western Australia.,Department of Neurology, Fiona Stanley Hospital, Perth, Western Australia
| | - Rocio Ruis
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria.,Brain and Mitochondrial Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria
| | - Jacqui Russell
- Genetic Metabolic Disorders Service, The Children's Hospital at Westmead, Sydney Children's Hospital Network, Sydney, New South Wales, Australia
| | | | - Christine Wools
- Department of Neurology, Calvary Health Care Bethlehem, Melbourne, Victoria, Australia
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8
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Tan THL, Stark RJ, Waterston JA, White O, Thyagarajan D, Monif M. Genetic prion disease: D178N with 129MV disease modifying polymorphism-a clinical phenotype. BMJ Neurol Open 2021; 2:e000074. [PMID: 33681799 PMCID: PMC7871715 DOI: 10.1136/bmjno-2020-000074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2020] [Indexed: 11/04/2022] Open
Abstract
Background Human prion diseases are a group of rare neurological diseases with a minority due to genetic mutations in the prion protein (PRNP) gene. The D178N mutation is associated with both Creutzfeldt-Jakob disease and fatal familial insomnia with the phenotype modified by a polymorphism at codon 129 with the methionine/valine (MV) polymorphism associated with atypical presentations leading to diagnostic difficulty. Case We present a case of fatal familial insomnia secondary to a PRNP D178N mutation with 129MV disease modifying polymorphism who had no family history, normal MRI, electroencephalography (EEG), cerebrospinal fluid (CSF) and positron emission tomography findings and a negative real-time quaking-induced conversion result. Conclusion Patients with genetic prion disease may have no known family history and normal EEG, MRI brain and CSF findings. PRNP gene testing should be considered for patients with subacute progressive neurological and autonomic dysfunction.
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Affiliation(s)
| | - Richard J Stark
- Neurology, Alfred Health, Melbourne, Victoria, Australia.,Neuroscience, Monash University Faculty of Medicine Nursing and Health Sciences, Clayton, Victoria, Australia
| | | | - Owen White
- Neuroscience, Monash University Faculty of Medicine Nursing and Health Sciences, Clayton, Victoria, Australia
| | - Dominic Thyagarajan
- Neuroscience, Monash University Faculty of Medicine Nursing and Health Sciences, Clayton, Victoria, Australia
| | - Mastura Monif
- Neurology, Alfred Health, Melbourne, Victoria, Australia.,Neuroscience, Monash University Faculty of Medicine Nursing and Health Sciences, Clayton, Victoria, Australia
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9
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Thomson CJ, Segrave RA, Racine E, Warren N, Thyagarajan D, Carter A. "He's Back so I'm Not Alone": The Impact of Deep Brain Stimulation on Personality, Self, and Relationships in Parkinson's Disease. Qual Health Res 2020; 30:2217-2233. [PMID: 32856559 DOI: 10.1177/1049732320951144] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Deep brain stimulation (DBS) for Parkinson's disease successfully alleviates motor symptoms, but unanticipated changes in personality, self, and relationships can occur. Little is known about how these nonmotor outcomes affect patients and families. We prospectively examined the experience and meaning of DBS-related changes in personality and self for patients and caregivers. In-depth, semi-structured interviews were conducted with 22 participants (11 patient-caregiver dyads) before and 9 months after DBS and analyzed using thematic analysis. We identified three themes present prior to DBS that reflected a time of anticipation, while three themes present after DBS reflected a process of adjustment. Participants noted both positive and negative personality changes, with some, but not all, attributing them to the stimulation. The risk of stimulation-related personality change should be weighed against the procedure's motor benefits and considered in the context of disease- and medication-related personality changes. Clinical implications including perioperative education and follow-up management are discussed.
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Affiliation(s)
| | | | - Eric Racine
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec, Canada
- Université de Montréal, Montreal, Quebec, Canada
- McGill University, Montreal, Quebec, Canada
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10
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Abstract
Emerging evidence suggests voice dysfunction is the earliest sign of motor impairment in Parkinson's disease (PD). The complexity and fine motor control involved in vocalization may result in dysfunction here before the limbs. The voice in PD demonstrates characteristic changes on perceptual and acoustic analyses. The physiological and anatomical correlates of these have been investigated through laryngoscopy, stroboscopy, photoglottography, laryngeal electromyography, computed-tomography, pulmonary function testing and aerodynamic assessments. These have revealed numerous abnormalities including incomplete glottic closure and vocal fold hypoadduction/bowing to account for these voice changes. Many of these phenomena are likely related to rigidity or bradykinesia of the laryngeal muscles. The early onset of voice changes is resonant with the pathophysiological insights offered by Braak's hypothesis and murine models of the disease. These physiological abnormalities and pathological models largely stand to support dopaminergic and non-dopaminergic mechanisms being implicated in the pathogenesis of voice dysfunction. This review focuses on characterizing the voice changes in PD. These stand as a promising area of enquiry to further our understanding of the pathophysiology of the disease and offer potential to be utilized as an early diagnostic biomarker or marker of disease progression.
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Affiliation(s)
- Andrew Ma
- Department of Neurology, The Alfred Hospital, Melbourne, Victoria 3004, Australia; Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria 3004, Australia
| | - Kenneth K Lau
- Monash Imaging, Monash Health, Melbourne, Victoria 3168, Australia; Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
| | - Dominic Thyagarajan
- Department of Neurology, The Alfred Hospital, Melbourne, Victoria 3004, Australia; Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria 3004, Australia.
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11
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McGuigan S, Zhou SH, Brosnan MB, Thyagarajan D, Bellgrove MA, Chong TTJ. Dopamine restores cognitive motivation in Parkinson's disease. Brain 2020; 142:719-732. [PMID: 30689734 DOI: 10.1093/brain/awy341] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 11/06/2018] [Accepted: 11/07/2018] [Indexed: 11/14/2022] Open
Abstract
Disorders of motivation, such as apathy, are common in Parkinson's disease, and a key feature of such disorders is a greater aversion to effort. In humans, the experience of cognitive effort is ubiquitous, and cognitive apathy has traditionally been considered distinct and separable from other subtypes. Surprisingly, however, the neurobiology of cognitive motivation is poorly understood. In particular, although dopamine has a well-characterized role in incentivizing physically effortful behaviour, a critical, unresolved issue is whether its facilitatory role generalizes to other domains. Here, we asked how dopamine modulates the willingness of patients with Parkinson's disease to invest cognitive effort in return for reward. We tested 20 patients with idiopathic Parkinson's disease across two counterbalanced sessions-ON and OFF their usual dopaminergic medication-and compared their performance to 20 healthy age-matched controls. We applied a novel task in which we manipulated cognitive effort as the number of rapid serial visual presentation streams to which participants had to attend. After training participants to ceiling performance, we then asked them to choose between a low-effort/low-reward baseline option, and a higher-effort/higher-reward offer. Computational models of choice behaviour revealed four key results. First, patients OFF medication were significantly less cognitively motivated than controls, as manifest by steeper cognitive effort discounting functions in the former group. Second, dopaminergic therapy improved this deficit, such that choices in patients ON medication were indistinguishable from controls. Third, differences in motivation were also accompanied by independent changes in the stochasticity of individuals' decisions, such that dopamine reduced the variability in choice behaviour. Finally, choices on our task correlated uniquely with the subscale of the Dimensional Apathy Scale that specifically indexes cognitive motivation, which suggests a close relationship between our laboratory measure of cognitive effort discounting and subjective reports of day-to-day cognitive apathy. Importantly, participants' choices were not confounded by temporal discounting, probability discounting, physical demand, or varying task performance. These results are the first to reveal the central role of dopamine in overcoming cognitive effort costs. They provide an insight into the computational mechanisms underlying cognitive apathy in Parkinson's disease, and demonstrate its amenability to dopaminergic therapy. More broadly, they offer important empirical support for prominent frameworks proposing a domain-general role for dopamine in value-based decision-making, and provide a critical link between dopamine and multidimensional theories of apathy.
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Affiliation(s)
- Sara McGuigan
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia
| | - Shou-Han Zhou
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia
| | - Méadhbh B Brosnan
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia
| | | | - Mark A Bellgrove
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia
| | - Trevor T-J Chong
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.,Department of Neurology, Alfred Health, Melbourne, Victoria, Australia.,Department of Clinical Neurosciences, St Vincent's Hospital, Melbourne, Victoria, Australia
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12
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Ellis S, Rang C, Kotsimbos T, Keating D, Finlayson F, Stark R, Thyagarajan D, Wilson J. CNS imaging studies in cystic fibrosis patients presenting with sudden neurological events. BMJ Open Respir Res 2019; 6:e000456. [PMID: 31423315 PMCID: PMC6688669 DOI: 10.1136/bmjresp-2019-000456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 12/15/2022] Open
Abstract
Background Acute neurological events may present as an extrapulmonary complication in patients with cystic fibrosis (CF). These events can be secondary to a range of different aetiologies. Methods A retrospective analysis of 476 medical records of CF patients attending a large teaching hospital between 2000 and 2018 was performed. Patients presenting with acute neurological events who had MRI brain imaging were evaluated. Patients who had headaches without associated neurological symptoms were excluded from this analysis. Results Acute neurological presentations, excluding headaches without associated neurological symptoms, were reported in 27 index patients out of the 476 patients. Of these, 16 patients had MRI brain imaging for review. Three patients suffered pathology secondary to vascular events, both ischaemic and haemorrhagic; four patients had evidence of ischaemia or infarction not consistent with a vascular territory stroke and the remaining patients experienced a range of different neurological events. The most common presentation among these patients was seizure activity, followed by a transient motor or sensory deficit. Conclusions Neurological complications are recognised among individuals with CF. Although rare, they can be secondary to a range of different aetiologies, including dysfunctional cell energetics. Additional studies are required to further evaluate this association.
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Affiliation(s)
- Samantha Ellis
- Department of Radiology, Alfred Health, Melbourne, Victoria, Australia
| | - Catherine Rang
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia
| | - Tom Kotsimbos
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
| | - Dominic Keating
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
| | - Felicity Finlayson
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia
| | - Richard Stark
- Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
| | | | - John Wilson
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
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13
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Mack HG, Milea D, Thyagarajan D, Fagan X. Transient bilateral optic disc oedema in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). Can J Ophthalmol 2018; 53:e208-e211. [DOI: 10.1016/j.jcjo.2017.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/10/2017] [Accepted: 11/20/2017] [Indexed: 11/16/2022]
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14
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Ducharlet K, Thyagarajan D, Ierino F, McMahon LP, Lee D. Perioperative risk assessment for successful kidney transplant in leigh syndrome: a case report. BMC Nephrol 2018; 19:23. [PMID: 29390978 PMCID: PMC5796450 DOI: 10.1186/s12882-018-0816-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 01/17/2018] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Leigh syndrome (LS) is a rare neurodegenerative mitochondrial disorder which typically presents in childhood but has a varied clinical course. Renal involvement such as proximal tubulopathy in patients with mitochondrial disorders has been described. However, end stage renal disease (ESRD) is uncommon and literature regarding patients undergoing kidney transplantation is limited. Successful deceased donor renal transplant has not been previously described in a patient with Leigh Syndrome. CASE PRESENTATION We report a 21-year-old Han Chinese man who presented with limb weakness and unsteady gait, which progressed rapidly over a period of months until he was wheelchair-bound. He subsequently developed ESRD and was commenced on hemodialysis. Investigations revealed a m.13513G > A mutation with clinical and radiological features consistent with LS. His mitochondrial disease stabilised and he underwent a multidisciplinary assessment for deceased donor kidney transplantation to identify and minimise the LS-associated perioperative risks and potential negative effects of immunosuppressants on his LS. Successful kidney transplantation followed with excellent graft function three and a half years post-transplant and improvement in the patient's physical function. CONCLUSION This case highlights the importance of careful pre-transplant perioperative risk assessment and post-transplant care in a rare and heterogeneous neurological disease to achieve an ultimately excellent clinical outcome. To our knowledge, this is the first report of successful deceased donor kidney transplant in a patient with known LS.
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Affiliation(s)
- Kathryn Ducharlet
- Department of Renal Medicine, Eastern Health Clinical School, Monash University, Level 2, 5 Arnold Street, Box Hill, Clayton, VIC, Australia.
| | - Dominic Thyagarajan
- Department of Neurosciences, Monash Health, 246 Clayton Road, Clayton, VIC, Australia
| | - Francesco Ierino
- Department of Nephrology, St Vincent's Hospital Melbourne, 55 Victoria Parade, Fitzroy, VIC, Australia
| | - Lawrence P McMahon
- Department of Renal Medicine, Eastern Health Clinical School, Monash University, Level 2, 5 Arnold Street, Box Hill, Clayton, VIC, Australia
| | - Darren Lee
- Department of Renal Medicine, Eastern Health Clinical School, Monash University, Level 2, 5 Arnold Street, Box Hill, Clayton, VIC, Australia
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15
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Perju-Dumbrava L, Lau K, Phyland D, Papanikolaou V, Finlay P, Beare R, Bardin P, Stuckey S, Kempster P, Thyagarajan D. Arytenoid cartilage movements are hypokinetic in Parkinson's disease: A quantitative dynamic computerised tomographic study. PLoS One 2017; 12:e0186611. [PMID: 29099841 PMCID: PMC5669420 DOI: 10.1371/journal.pone.0186611] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 10/04/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Voice change is one of the earliest features of Parkinson's disease. However, quantitative studies of vocal fold dynamics which are needed to provide insight into disease biology, aid diagnosis, or track progression, are few. METHODS We therefore quantified arytenoid cartilage movements and glottic area during repeated phonation in 15 patients with Parkinson's disease (symptom duration < 6 years) and 19 controls, with 320-slice computerised tomography (CT). We related these measures to perceptual voice evaluations and spirometry. We hypothesised that Parkinson's disease patients have a smaller inter-arytenoid distance, a preserved or larger glottic area because vocal cord bowing has previously been reported, less variability in loudness, more voice dysdiadochokinesis and breathiness and a shortened phonation time because of arytenoid hypokinesis relative to glottic area. RESULTS Inter-arytenoid distance in Parkinson's disease patients was moderately smaller (Mdn = 0.106, IQR = 0.091-0.116) than in controls (Mdn = 0.132, IQR = 0.116-0.166) (W = 212, P = 0.015, r = -0.42), normalised for anatomical and other inter-subject variance, analysed with two-tailed Wilcoxon's rank sum test. This finding was confirmed in a linear mixed model analysis-Parkinson's disease significantly predicted a reduction in the dependent variable, inter-arytenoid distance (b = -0.87, SEb = 0.39, 95% CI [-1.66, -0.08], t(31) = -2.24, P = 0.032). There was no difference in glottic area. On perceptual voice evaluation, patients had more breathiness and dysdiadochokinesis, a shorter maximum phonation time, and less variability in loudness than controls. There was no difference in spirometry after adjustment for smoking history. CONCLUSIONS As predicted, vocal fold adduction movements are reduced in Parkinson's disease on repeated phonation but glottic area is maintained. Some perceptual characteristics of Parkinsonian speech reflect these changes. We are the first to use 320-slice CT to study laryngeal motion. Our findings indicate how Parkinson's disease affects intrinsic laryngeal muscle position and excursion.
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Affiliation(s)
| | - Ken Lau
- Department of Medical Imaging, Monash Medical Center, Clayton, Victoria, Australia
| | - Debbie Phyland
- Department of Surgery, Monash Medical Center, Clayton, Victoria, Australia
| | - Vicki Papanikolaou
- Department of Respiratory Medicine, Monash Medical Center, Clayton, Victoria, Australia
| | - Paul Finlay
- Department of Respiratory Medicine, Monash Medical Center, Clayton, Victoria, Australia
| | - Richard Beare
- Department of Neuroscience, Monash Medical Center, Clayton, Victoria, Australia
| | - Philip Bardin
- Department of Respiratory Medicine, Monash Medical Center, Clayton, Victoria, Australia
| | - Stephen Stuckey
- Department of Medical Imaging, Monash Medical Center, Clayton, Victoria, Australia
| | - Peter Kempster
- Department of Neuroscience, Monash Medical Center, Clayton, Victoria, Australia
| | - Dominic Thyagarajan
- Department of Neuroscience, Monash Medical Center, Clayton, Victoria, Australia
- * E-mail:
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16
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Wasser CI, Evans F, Kempnich C, Glikmann-Johnston Y, Andrews SC, Thyagarajan D, Stout JC. Emotion recognition in Parkinson's disease: Static and dynamic factors. Neuropsychology 2017; 32:230-234. [PMID: 29035069 DOI: 10.1037/neu0000400] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE The authors tested the hypothesis that Parkinson's disease (PD) participants would perform better in an emotion recognition task with dynamic (video) stimuli compared to a task using only static (photograph) stimuli and compared performances on both tasks to healthy control participants. METHOD In a within-subjects study, 21 PD participants and 20 age-matched healthy controls performed both static and dynamic emotion recognition tasks. The authors used a 2-way analysis of variance (controlling for individual participant variance) to determine the effect of group (PD, control) on emotion recognition performance in static and dynamic facial recognition tasks. RESULTS Groups did not significantly differ in their performances on the static and dynamic tasks; however, the trend was suggestive that PD participants performed worse than controls. CONCLUSIONS PD participants may have subtle emotion recognition deficits that are not ameliorated by the addition of contextual cues, similar to those found in everyday scenarios. Consistent with previous literature, the results suggest that PD participants may have underlying emotion recognition deficits, which may impact their social functioning. (PsycINFO Database Record
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Affiliation(s)
- Cory I Wasser
- Monash Institute of Cognitive and Clinical Neuroscience, School of Psychological Sciences, Monash University
| | - Felicity Evans
- Monash Institute of Cognitive and Clinical Neuroscience, School of Psychological Sciences, Monash University
| | - Clare Kempnich
- Monash Institute of Cognitive and Clinical Neuroscience, School of Psychological Sciences, Monash University
| | - Yifat Glikmann-Johnston
- Monash Institute of Cognitive and Clinical Neuroscience, School of Psychological Sciences, Monash University
| | - Sophie C Andrews
- Monash Institute of Cognitive and Clinical Neuroscience, School of Psychological Sciences, Monash University
| | | | - Julie C Stout
- Monash Institute of Cognitive and Clinical Neuroscience
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17
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Desai N, Rao AS, Palaniswami P, Thyagarajan D, Palaniswami M. Arytenoid cartilage feature point detection using laryngeal 3D CT images in Parkinson's disease. Annu Int Conf IEEE Eng Med Biol Soc 2017; 2017:1820-1823. [PMID: 29060243 DOI: 10.1109/embc.2017.8037199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Parkinson's disease is a neurodegenerative disorder that results in progressive degeneration of nerve cells. It is generally associated with the deficiency of dopamine, a neurotransmitter involved in motor control of humans and thus affects the motor system. This results in abnormal vocal fold movements in majority of the Parkinson's patients. Analysis of vocal fold abnormalities may provide useful information to assess the progress of Parkinson's disease. This is accomplished by measuring the distance between the arytenoid cartilages during phonation. In order to automate this process of identifying arytenoid cartilages from CT images, in this work, a rule-based approach is proposed to detect the arytenoid cartilage feature points on either side of the airway. The proposed technique detects feature points by localizing the anterior commissure and analyzing airway boundary pixels to select the optimal feature point based on detected pixels. The proposed approach achieved 83.33% accuracy in estimating clinically-relevant feature points, making the approach suitable for automated feature point detection. To the best of our knowledge, this is the first such approach to detect arytenoid cartilage feature points using laryngeal 3D CT images.
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18
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Fujiwara M, Ding C, Kaunitz L, Stout JC, Thyagarajan D, Tsuchiya N. Optokinetic nystagmus reflects perceptual directions in the onset binocular rivalry in Parkinson's disease. PLoS One 2017; 12:e0173707. [PMID: 28288201 PMCID: PMC5348009 DOI: 10.1371/journal.pone.0173707] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 02/24/2017] [Indexed: 11/20/2022] Open
Abstract
Optokinetic nystagmus (OKN), the reflexive eye movements evoked by a moving field, has recently gained interest among researchers as a useful tool to assess conscious perception. When conscious perception and stimulus are dissociated, such as in binocular rivalry-when dissimilar images are simultaneously presented to each eye and perception alternates between the two images over time-OKN correlates with perception rather than with the physical direction of the moving field. While this relationship is well established in healthy subjects, it is yet unclear whether it also generalizes to clinical populations, for example, patients with Parkinson's disease. Parkinson's disease is a motor disorder, causing tremor, slow movements and rigidity. It may also be associated with oculomotor deficits, such as impaired saccades and smooth pursuit eye movements. Here, we employed short-duration, onset binocular rivalry (2 s trial of stimulus presentation followed by 1 s inter-trial interval) with moving grating stimuli to assess OKN in Parkinson's disease patients (N = 39) and controls (N = 29) of a similar age. Each trial was either non-rivalrous (same stimuli presented to both eyes) or rivalrous, as in binocular rivalry. We analyzed OKN to discriminate direction of stimulus and perception on a trial-by-trial basis. Although the speed of slow-phase OKN was slower in the patients, discriminability of conscious perception based on OKN was comparable between the groups. Treatment with anti-Parkinson drugs and deep brain stimulation improved motor ability of patients, but did not impact on OKN. Furthermore, OKN-based measures were robust and their latencies were shorter than manual button-based measures in both groups and stimulus conditions. To our knowledge, our study is the first to demonstrate that OKN can be used as a reliable indicator of conscious perception in binocular rivalry even in Parkinson's disease patients in whom impaired manual dexterity may render button-press reports less reliable.
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Affiliation(s)
- Mana Fujiwara
- School of Psychological Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Araya Brain Imaging, Tokyo, Japan
| | - Catherine Ding
- Department of Neurosciences, Southern Clinical School, Monash Health, Melbourne, Victoria, Australia
| | - Lisandro Kaunitz
- School of Psychological Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, Tokyo, Japan
| | - Julie C. Stout
- School of Psychological Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Victoria, Australia
| | - Dominic Thyagarajan
- Department of Neurosciences, Southern Clinical School, Monash Health, Melbourne, Victoria, Australia
| | - Naotsugu Tsuchiya
- School of Psychological Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Victoria, Australia
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19
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Ding C, Palmer CJ, Hohwy J, Youssef GJ, Paton B, Tsuchiya N, Stout JC, Thyagarajan D. Parkinson's disease alters multisensory perception: Insights from the Rubber Hand Illusion. Neuropsychologia 2017; 97:38-45. [DOI: 10.1016/j.neuropsychologia.2017.01.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/17/2017] [Accepted: 01/29/2017] [Indexed: 12/14/2022]
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Hewavitharanage S, Gubbi J, Thyagarajan D, Lau K, Palaniswami M. Estimation of vocal fold plane in 3D CT images for diagnosis of vocal fold abnormalities. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2015:3105-8. [PMID: 26736949 DOI: 10.1109/embc.2015.7319049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Vocal folds are the key body structures that are responsible for phonation and regulating air movement into and out of lungs. Various vocal fold disorders may seriously impact the quality of life. When diagnosing vocal fold disorders, CT of the neck is the commonly used imaging method. However, vocal folds do not align with the normal axial plane of a neck and the plane containing vocal cords and arytenoids does vary during phonation. It is therefore important to generate an algorithm for detecting the actual plane containing vocal folds. In this paper, we propose a method to automatically estimate the vocal fold plane using vertebral column and anterior commissure localization. Gray-level thresholding, connected component analysis, rule based segmentation and unsupervised k-means clustering were used in the proposed algorithm. The anterior commissure segmentation method achieved an accuracy of 85%, a good estimate of the expert assessment.
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21
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Hewavitharanage S, Gubbi J, Thyagarajan D, Lau K, Palaniswami M. Automatic segmentation of the rima glottidis in 4D laryngeal CT scans in Parkinson's disease. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2015:739-42. [PMID: 26736368 DOI: 10.1109/embc.2015.7318468] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Parkinson's disease (PD) is a progressive, incurable neuro-degenerative disease. Symptoms appear when approximately 70% of mid-brain dopaminergic neurons have died. Temporal analysis of the calculated area of the rima glottidis may give an indication of vocal impairment. In this paper, we present an automatic segmentation algorithm to segment the rima glottidis from 4D CT images using texture features and support vector machines (SVM). Automatic two dimensional region growing is then applied as a post processing step to segment the area accurately. The proposed segmentation algorithm resulted in accurate segmentation and we demonstrate a high correlation between the manually segmented area and automatic segmentation.
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22
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Kocsis G, McCulloch TA, Thyagarajan D, Wallace WA. The biological response to a failed extra-articular polyester ligament used for AC Joint reconstruction at the shoulder girdle: a retrieval analysis of five cases. Bone Joint J 2015; 97-B:83-8. [PMID: 25568418 DOI: 10.1302/0301-620x.97b1.34357] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The LockDown device (previously called Surgilig) is a braided polyester mesh which is mostly used to reconstruct the dislocated acromioclavicular joint. More than 11,000 have been implanted worldwide. Little is known about the tissue reaction to the device nor to its wear products when implanted in an extra-articular site in humans. This is of importance as an adverse immunological reaction could result in osteolysis or damage to the local tissues, thereby affecting the longevity of the implant. We analysed the histology of five LockDown implants retrieved from five patients over the last seven years by one of the senior authors. Routine analysis was carried out in all five cases and immunohistochemistry in one. The LockDown device acts as a scaffold for connective tissue which forms an investing fibrous pseudoligament. The immunological response at the histological level seems favourable with a limited histiocytic and giant cell response to micron-sized wear particles. The connective tissue envelope around the implant is less organised than a native ligament.
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Affiliation(s)
- G Kocsis
- Shoulder and Elbow Unit, Nottingham University Hospitals, 69 Bargate, Grimsby, DN34 5BD, Nottingham, UK
| | - T A McCulloch
- Department of Histopathology, City Campus, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham NG5 1PB, UK
| | - D Thyagarajan
- Northern General Hospital, Herries Road, Sheffield, South Yorkshire S5 7AU, UK
| | - W A Wallace
- Academic Orthopaedics Trauma and Sports Medicine, Queens Medical Centre, Nottingham NG7 2UH, UK
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23
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Slater L, Stuckey SL, Thyagarajan D, Chandra R. Reversible Corona Radiata Diffusion Restriction in Hypoglycemic Coma. Neurohospitalist 2015; 5:45-6. [DOI: 10.1177/1941874414532473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- L. Slater
- Department of Diagnostic Imaging, Neuroradiology service, Monash Health, Melbourne, Australia
| | - S. L. Stuckey
- Department of Diagnostic Imaging, Neuroradiology service, Monash Health, Melbourne, Australia
| | - D. Thyagarajan
- Department of Neurology, Monash Health, Melbourne, Australia
| | - R.V. Chandra
- Department of Diagnostic Imaging, Neuroradiology service, Monash Health, Melbourne, Australia
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24
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Bhaisare DB, Thyagarajan D, Churchil RR, Punniamurthy N. Effect of dietary supplementation of herbal seeds on carcass traits of turkey poults. Vet World 2014. [DOI: 10.14202/vetworld.2014.938-942] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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25
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Perju-Dumbrava LD, McDonald M, Kneebone AC, Long R, Thyagarajan D. Sustained response to deep brain stimulation in LRRK2 parkinsonism with the Y1699C mutation. J Parkinsons Dis 2014; 2:269-71. [PMID: 23938256 DOI: 10.3233/jpd-012121] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Although effective deep brain stimulation of the subthalamic nucleus (STN-DBS) is reported in G2019S leucine-rich repeat kinase 2 (LRRK2) parkinsonism, response to surgery in other LRRK2 mutations has not been previously reported. We present an affected individual from the Lincolnshire pedigree (Y1699C), on whom bilateral STN-DBS was performed to control severe motor fluctuations and dyskinesias. He showed a marked improvement in Unified Parkinson's Disease Rating Scale (UPDRS) Part III scores in the "on" and "off" states, sustained for more than three years. Bilateral STN-DBS in LRRK2-parkinsonism with the Y1699C mutation can be as effective as in sporadic PD.
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Affiliation(s)
- L D Perju-Dumbrava
- Department of Neurosciences, Monash Medical Centre, Clayton, VIC, Australia
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26
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Baxter M, Uddin N, Raghav S, Leong P, Low K, Hamza K, Holmes PW, Hamilton G, Thyagarajan D, Lau K, Bardin PG. Abnormal vocal cord movement treated with botulinum toxin in patients with asthma resistant to optimised management. Respirology 2014; 19:531-7. [PMID: 24655302 DOI: 10.1111/resp.12271] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 01/01/2014] [Accepted: 01/07/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVE Abnormal vocal cord movement may coexist with asthma and cause additional upper/middle airway obstruction. The condition may be a form of muscular dystonia that could contribute to asthma resistant to optimised treatments. Botulinum toxin causes temporary paralysis of muscle and may be an effective local treatment that improves asthma control. METHODS In an observational study, we evaluated the benefits of unilateral vocal cord injection with botulinum toxin in 11 patients (total 24 injections). Subjects had asthma resistant to optimised treatment and abnormal vocal cord movement. Responses after botulinum toxin treatment were assessed using asthma control test (ACT) scores, vocal cord narrowing quantified by computerised tomography (CT) of the larynx and spirometry. Side-effects were recorded. RESULTS ACT scores improved overall (9.1 ± 2.4 before and 13.5 ± 4.5 after treatment; difference 4.4 ± 4.2; P < 0.001). There was also an improvement in airway size on CT larynx (time below lower limit of normal at baseline 39.4 ± 37.63% and improved to 17.6 ± 25.6% after injection; P = 0.032). Spirometry was not altered. One patient experienced an asthma exacerbation but overall side-effects were moderate, chiefly dysphonia and dysphagia. CONCLUSIONS Although a placebo effect cannot be ruled out, local injection of botulinum toxin may be an effective treatment for intractable asthma associated with abnormal vocal cord movement. Further mechanistic studies and a double-blind randomised controlled trial of botulinum toxin treatment are merited.
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Affiliation(s)
- Malcolm Baxter
- Ear, Nose and Throat Surgery, Monash Medical Centre and Monash Institute of Medical Research (MIMR), Monash University, Melbourne, Victoria, Australia
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Abstract
Radiotherapy may cause central or peripheral nervous system complications, reported examples being myelopathy, brachial/lumbosacral plexopathies or predominantly motor lumbosacral radiculopathy. In the literature some studies regard camptocormia as a paravertebral myopathy and others as of neurogenic origin. We present a patient who developed camptocormia, 42 years after radiation therapy to the para-aortic and inguinal area.
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Affiliation(s)
- Linda Kelly
- Monash University, Melbourne, Victoria, Australia
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28
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Phan TG, Gureyev T, Nesterets Y, Ma H, Thyagarajan D. Novel Application of EEG Source Localization in the Assessment of the Penumbra. Cerebrovasc Dis 2012; 33:405-7. [DOI: 10.1159/000336332] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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29
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Slee M, Finkemeyer J, Krupa M, Raghupathi R, Gardner J, Blumbergs P, Agzarian M, Thyagarajan D. A novel mitochondrial DNA deletion producing progressive external ophthalmoplegia associated with multiple sclerosis. J Clin Neurosci 2011; 18:1318-24. [DOI: 10.1016/j.jocn.2011.02.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Revised: 01/27/2011] [Accepted: 02/06/2011] [Indexed: 11/16/2022]
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Parasivam S, Cowey M, Day B, Thyagarajan D. A unique case of cortical myoclonus sensitive to visual stimuli in the peripersonal space. Mov Disord 2009; 24:422-5. [PMID: 19084909 DOI: 10.1002/mds.21931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Multimodal representation of peripersonal or near space has been demonstrated in the brain of the nonhuman primate through invasive electrophysiological experiments. Representation of peripersonal space in the human brain has been inferred from extinction experiments and functional imaging studies. We present a unique case of lower limb myoclonus in a patient with common variable immunodeficiency which is sensitive to visual stimuli in the peripersonal space and light touch. This case provides further evidence for near space representation in the human brain. We hypothesize that somatopically organized multimodal areas exist in the human brain which code for peripersonal space.
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Affiliation(s)
- Sharavanan Parasivam
- Department of Neurology, Flinders Medical Centre, Bedford Park, Adelaide, South Australia.
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31
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Johnson D, Thyagarajan D. Restless legs syndrome. Aust Prescr 2008. [DOI: 10.18773/austprescr.2008.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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33
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van den Bos M, Marotta R, Goldup S, Chataway T, Firgaira F, Thyagarajan D. Writer's cramp in an Australian pedigree with DYT1 dystonia. J Clin Neurosci 2008; 11:537-9. [PMID: 15177405 DOI: 10.1016/s0967-5868(03)00226-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2003] [Accepted: 07/16/2003] [Indexed: 11/29/2022]
Abstract
Oppenheim's or DYT1 dystonia is a primary dystonia typically presenting in a limb at an early age and usually becoming generalised within 5 years. Over the last decade research into this debilitating disorder has progressed considerably, enabling the identification of a genetic lesion (a 3bp deletion in the DYT1 gene) now widely accepted as the cause of a majority of cases. This case report presents the first molecularly diagnosed pedigree of an Australian family with DYT1 dystonia, which presented as writer's cramp in the 15-year-old proband and two of his cousins.
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Affiliation(s)
- Mehdi van den Bos
- Department of Neurology, Flinders Medical Center, South Australia, Australia
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Abstract
The patient initially presented with bilateral optic neuritis and periventricular cranial MRI abnormalities in the context of syphilis. Blood was positive but cerebrospinal fluid testing was negative for specific syphilis markers and he was oligoclonal cerebrospinal fluid (CSF) band negative. He initially responded well to penicillin and corticosteriod treatment, but went on to develop the clinical syndrome of neuromyelitis optica (NMO). Testing for the presence of the serum autoantibody for aquaporin-4 was negative. This patient appears to represent another case of post-infectious NMO. Possible pathogenesis of this post-syphilis NMO syndrome in the patient is discussed. Multiple Sclerosis 2008; 14: 268—271. http://msj.sagepub.com
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Affiliation(s)
- Robert A Wilcox
- Department of Neurology, Flinders Medical Centre, Bedford Park, SA, 5041, Australia,
| | - James Burrow
- Department of Medicine, Royal Darwin Hospital, Casuarina, NT, 0811, Australia
| | - Mark Slee
- Department of Neurology, Flinders Medical Centre, Adelaide, 5042, Australia
| | - Jamie Craig
- Department of Neurology, Flinders Medical Centre, Bedford Park, SA, 5041, Australia
| | - Dominic Thyagarajan
- Department of Neurology, Flinders Medical Centre, Bedford Park, SA, 5041, Australia
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Wilcox RA, Churchyard A, Dahl HH, Hutchison WM, Kirby DM, Thyagarajan D. Levodopa response in Parkinsonism with multiple mitochondrial DNA deletions. Mov Disord 2007; 22:1020-3. [PMID: 17357142 DOI: 10.1002/mds.21416] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report a patient with an autosomal dominant chronic progressive external ophthalmoplegia phenotype associated with multiple mtDNA deletions in muscle from a family in which linkage analysis excluded mutations in DNA polymerase gamma (POLG), adenine nucleotide translocase (ANT-1) or C10orf2 (Twinkle). She presented with prominent Parkinsonism characterized by prolonged benefit from levodopa (L-dopa) and the later development of L-dopa induced dyskinesias and motor fluctuations. Thus L-dopa responsiveness, L-dopa induced dyskinesias and motor fluctuations may also occur in atypical Parkinsonism of mitochondrial disease, just as they may in multiple system atrophy.
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Affiliation(s)
- Robert A Wilcox
- Department of Neurology, Flinders Medical Centre, SA, Australia.
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Rudkin AK, Wilcox RA, Slee M, Kupa A, Thyagarajan D. Relapsing encephalopathy with headache: an unusual presentation of isolated intracranial neurosarcoidosis. J Neurol Neurosurg Psychiatry 2007; 78:770-1. [PMID: 17575024 PMCID: PMC2117705 DOI: 10.1136/jnnp.2006.104703] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Abstract
We report two patients with cryptococcal meningitis and combined immunodeficiency with unusual magnetic resonance imaging findings of gadolinium-enhancing white matter lesions, quite different from cryptococcomas and seen prior to anti-fungal treatment. The lesions resembled demyelinating plaques and resolved. In one patient, biopsy of the lesion revealed cryptococci, non-specific inflammatory changes and occasional small perivascular lymphocyte collections, but not demyelination. Leukoencephalopathy, previously rarely observed in Cryptococcal meningitis, was thought to be the sequelae of amphotericin toxicity. Our cases demonstrate cryptococcal meningitis may present with leukoencephalopathy, possibly as an immune response to the organism.
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Affiliation(s)
- R A Wilcox
- Department of Neurology, Flinders Medical Center, Adelaide, SA, Australia.
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Hutchison WM, Thyagarajan D, Poulton J, Marchington DR, Kirby DM, Manji SSM, Dahl HHM. Clinical and molecular features of encephalomyopathy due to the A3302G mutation in the mitochondrial tRNA(Leu(UUR)) gene. ACTA ACUST UNITED AC 2006; 62:1920-3. [PMID: 16344351 DOI: 10.1001/archneur.62.12.1920] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The mitochondrial DNA mutation A3302G in the tRNA(Leu(UUR)) gene causes respiratory chain complex I deficiency. The main clinical feature appears to be a progressive mitochondrial myopathy with proximal muscle weakness. OBJECTIVE To report on clinical and molecular features in 4 novel patients with the A3302G mutation. DESIGN Case reports. PATIENTS Four patients (3 of whom are from the same family) with a myopathy caused by the A3302G mitochondrial DNA mutation. MAIN OUTCOME MEASURE Identification of the A3302G mutation by DNA sequencing. RESULTS All 4 patients had an adult-onset progressive mitochondrial myopathy with proximal muscle weakness, resulting in exercise intolerance. In 2 unrelated patients, upper limb reflexes were absent with preservation of at least some lower limb reflexes. Other features including hearing loss, recurrent headaches, ptosis, progressive external ophthalmoplegia, and depression were present. CONCLUSION While the dominant clinical features of the A3302G mutation were exercise intolerance and proximal muscle weakness, other features of mitochondrial encephalomyopathies, previously not described for this mutation, were present.
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Affiliation(s)
- Wendy M Hutchison
- Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia
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Abstract
We describe an unusual form of facial myoclonus activated by speech in 3 patients with different underlying neurological diseases and present the electrophysiological investigations and results of structural and functional imaging. In 1 of 2 patients in whom jerk-locked electroencephalogram (EEG) back-averaging was done, a cortical potential clearly preceded the facial jerks. In the second patient, a cortical potential preceding the jerk was not certain. In the third patient, the resting EEG contained outbursts of symmetric, slower frequencies of indeterminate significance. An epileptiform disorder was suspected in this patient.
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Affiliation(s)
- Mark Slee
- Flinders Medical Centre, Adelaide, South Australia, Australia
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Thyagarajan D, Chataway T, Li R, Gai WP, Brenner M. Dominantly-inherited adult-onset leukodystrophy with palatal tremor caused by a mutation in the glial fibrillary acidic protein gene. Mov Disord 2005; 19:1244-8. [PMID: 15390001 DOI: 10.1002/mds.20161] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We report on a pedigree of dominantly-inherited, adult-onset Alexander disease caused by the glial fibrillary acidic protein (GFAP) gene mutation, R416W. This pedigree highlights the importance of genetic analysis of the GFAP gene in leukodystrophy with palatal tremor.
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Affiliation(s)
- Dominic Thyagarajan
- Department of Neurology, Flinders Medical Centre and Flinders University, South Australia, Australia.
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Kirby DM, Boneh A, Chow CW, Ohtake A, Ryan MT, Thyagarajan D, Thorburn DR. Low mutant load of mitochondrial DNA G13513A mutation can cause Leigh's disease. Ann Neurol 2003; 54:473-8. [PMID: 14520659 DOI: 10.1002/ana.10687] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Respiratory chain complex I deficiency is a common cause of Leigh's disease (LD) and can be caused by mutations in genes encoded by either nuclear or mitochondrial DNA (mtDNA). Most pathogenic mtDNA mutations act recessively and only cause disease when present at high mutant loads (typically >90%) in tissues such as muscle and brain. Two mitochondrial DNA mutations in complex I subunit genes, G14459A in ND6, and T12706C in ND5, have been associated with complex I deficiency and LD. We report another ND5 mutation, G13513A, in three unrelated patients with complex I deficiency and LD. The G13513A mutation was present at mutant loads of approximately 50% or less in all tissues tested, including multiple brain regions. The threshold mutant load for causing a complex I defect in cultured cells was approximately 30%. Blue Native polyacrylamide gel electrophoresis showed that fibroblasts with 45% G13513A mutant load had approximately 50% of the normal amount of fully assembled complex I. Fibroblasts with greater than 97% of the ND6 G14459A mutation had only 20% fully assembled complex I, suggesting that both mutations disrupt complex I assembly or turnover. We conclude that the G13513A mutation causes a complex I defect when present at unusually low mutant load and may act dominantly.
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Affiliation(s)
- Denise M Kirby
- Murdoch Children's Research Institute, University of Melbourne, Victoria, Australia
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Affiliation(s)
- Dominic Thyagarajan
- Department of Neurology, Flinders Medical Centre, Bedford Park, South Australia 5042, Australia
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Thyagarajan D. Genetics of movement disorders: an abbreviated overview. Stereotact Funct Neurosurg 2002; 77:48-60. [PMID: 12378057 DOI: 10.1159/000064597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Linkage of the Huntington's disease gene to chromosome 4 in 1983 marked the birth of modern genetics in movement disorders. The discovery that an expanded trinucleotide DNA repeat was central to the mechanism of this disease has been repeated over and over in a growing list of inherited ataxias. In 1997, a different mutation and genetic mechanism was discovered in a severe type of generalized primary torsion dystonia - Oppenheim's dystonia. Before this, only the genetic cause for rare metabolic dystonias was known, notably dopa-responsive (Segawa's) dystonia. In the same year, from the identification of mutation in the alpha-synuclein gene in rare pedigrees with autosomal dominant parkinsonism, arose the concept that Parkinson's disease may be part of a broader group of 'synucleinopathies', in which there is a fundamental defect in protein processing. In the following year, mutations in autosomal recessive juvenile onset parkinsonism were found in a gene called 'parkin'. Parkin mutations are a more common cause of parkinsonism than the rare alpha-synuclein mutations, particularly in young-onset disease. However, a most important understanding, occurring in the last year, has been the relationship between the parkin gene product, alpha-synuclein and abnormal protein degradation in the cell. A unified theory of neuronal death in Parkinson's disease is emerging, pointing to potential new therapies in the future.
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Affiliation(s)
- D Thyagarajan
- Department of Neurology, Flinders Medical Centre, Bedford Park, SA, Australia.
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Abstract
We have analyzed Twinkle, the causative gene for autosomal dominant progressive external ophthalmoplegia (adPEO) on chromosome 10, in 11 Australian autosomal dominant progressive external ophthalmoplegia families of Caucasian origin, and investigated whether there are distinct molecular and clinical features associated with mutations in this gene. We found two new mutations in Twinkle, in 3 of the 11 pedigrees examined. One resides in the linker region of this gene while the other is in the primase domain. Both regions are highly conserved between species. Multiple deletions in the mtDNA from muscle are not always prominent and there are significant variations in the clinical presentation within and between families with mutations in the Twinkle gene. Therefore, genotype/phenotype predictions are difficult. No mutations were found in adenine nucleotide translocator 1 (ANT1), another known adPEO causative gene, in four of the seven remaining families investigated. Thus, Twinkle appears to be the most common gene associated with adPEO in Australian families.
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Affiliation(s)
- Sharon Lewis
- Murdoch Childrens Research Institute, The Royal Childrens Hospital, Parkville, Victoria 3052, Australia
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McKelvie PA, Collins S, Thyagarajan D, Trost N, Sheorey H, Byrne E. Meningoencephalomyelitis with vasculitis due to varicella zoster virus: a case report and review of the literature. Pathology 2002; 34:88-93. [PMID: 11902456 DOI: 10.1080/00313020120105705] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Varicella zoster virus (VZV) encephalitis is associated with large or small vessel vasculopathy. We report the case of a 67-year-old woman with a history of non-Hodgkin's lymphoma and cancers of the breast and colon, who presented with a zosteriform rash and Brown-Sequard syndrome. Despite 10 days therapy with intravenous acyclovir, meningoencephalitis developed and the patient died 15 days after onset of neurological symptoms. Autopsy showed meningoencephalomyelitis with necrotising vasculitis of leptomeningeal vessels, which is a rare complication of VZV, and we review the literature of the nine similar published cases. Polymerase chain reaction of cerebrospinal fluid for VZV was negative 6 days after onset of neurological symptoms, but became positive by day 10. Only one multinucleated giant cell with intranuclear Cowdry type A inclusions was seen within an endothelial cell in a leptomeningeal vessel involved by vasculitis.
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Affiliation(s)
- Penelope A McKelvie
- Department of Anatomical Pathology, St Vincent's Hospital, Fitzroy, Victoria, Australia.
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46
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Quigley A, Reardon K, Kapsa R, Dennett X, Byrne E, Thyagarajan D. A novel clinical phenotype of myopathy, sensorimotor neuropathy, infertility, and hypogonadism with multiple mitochondrial DNA deletions. J Clin Neuromuscul Dis 2001; 3:77-82. [PMID: 19078659 DOI: 10.1097/00131402-200112000-00006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe a patient with myopathy, sensorimotor neuropathy, hypogonadism, and infertility with abnormal sperm mobility and morphology. Analysis of the deltoid muscle DNA revealed a G to A change at nt 1102 in the twinkle gene and multiple mitochondrial DNA deletions. Histochemistry revealed "ragged-red" fibers and many cytochrome-c oxidase negative fibers (32%) that lacked the mitochondrial encoded respiratory chain subunits I and II and the nuclear encoded subunit VIc. Respiratory chain enzyme analysis showed severe deficiency of complex I, III, and IV. This patient has no documented family history of progressive external ophthalmoplegia, which suggests either a sporadic or autosomal-recessive syndrome. This case is a novel phenotype for twinkle gene mutations and multiple mitochondrial DNA deletion syndromes, as these syndromes generally follow an autosomal-dominant inheritance pattern.
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Affiliation(s)
- A Quigley
- From the *Melbourne Neuromuscular Research Institute, St. Vincent's Hospital, Fitzroy, Victoria, Australia; and daggerState Neuropathology Service, Department of Pathology, Melbourne University, Parkville, Victoria, Australia
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47
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Lewis S, Hutchison W, Di Nezza L, Thyagarajan D, Marotta R, Dahl H. Refinement of the adPEO linked locus on Chr10 and analysis of MRS4 and three other candidate genes. FEBS Lett 2001; 500:183-5. [PMID: 11445082 DOI: 10.1016/s0014-5793(01)02612-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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48
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Thyagarajan D, Bressman S, Bruno C, Przedborski S, Shanske S, Lynch T, Fahn S, DiMauro S. A novel mitochondrial 12SrRNA point mutation in parkinsonism, deafness, and neuropathy. Ann Neurol 2001. [DOI: 10.1002/1531-8249(200011)48:5<730::aid-ana6>3.0.co;2-0] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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49
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Thyagarajan D, Bressman S, Bruno C, Przedborski S, Shanske S, Lynch T, Fahn S, DiMauro S. A novel mitochondrial 12SrRNA point mutation in parkinsonism, deafness, and neuropathy. Ann Neurol 2000; 48:730-6. [PMID: 11079536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The objective of this study was to determine whether a mitochondrial DNA mutation and defective oxidative phosphorylation are present in a pedigree with maternally inherited sensorineural deafness, levodopa-responsive parkinsonism, and neuropathy. We sequenced the mitochondrial-encoded ribosomal RNA, cytochrome c oxidase, and transfer RNA genes by cycle sequencing. A polymerase chain reaction-based restriction enzyme assay with mismatched primers was employed to show heteroplasmy of a novel 12SrRNA mutation in the proband and to screen control subjects. Spectrophotometric mitochondrial respiratory chain assays were performed in transformed lymphoblasts from the proband and 12 normal controls. A novel, heteroplasmic, maternally inherited 12SrRNA point mutation (T1095C) was found in the pedigree. Respiratory chain enzyme analysis in cultured lymphocytes from the proband revealed a significant reduction in cytochrome c oxidase activity. Secondary structure predicts that this mutation disrupts a highly conserved loop in the small subunit ribosomal RNA, which is important in the initiation of mitochondrial protein synthesis. The mutation was not found in 270 controls of diverse ethnic origins. We conclude that this mutation is pathogenic and causes an oxidative phosphorylation defect by interfering with mitochondrial protein synthesis.
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Affiliation(s)
- D Thyagarajan
- Center for Parkinson's Disease and Other Movement Disorders, New York, NY, USA
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50
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Abstract
The authors describe two patients with fixed shoulder elevation and prominent regional muscle hypertrophy that developed within days after local minor injury. The condition lacked several typical features of dystonia, such as the presence of torsional movements, task specificity, or relief by antagonistic gestures. These patient reports add to the growing literature indicating that persistent post-traumatic abnormal postures and muscle hypertrophy in different body parts may be a distinct response of the nervous system to injury.
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