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Tanner CM, Ostrem JL. Parkinson's Disease. N Engl J Med 2024; 391:442-452. [PMID: 39083773 DOI: 10.1056/nejmra2401857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Affiliation(s)
- Caroline M Tanner
- From the Movement Disorders and Neuromodulation Center, Department of Neurology, Weill Institute for Neuroscience, University of California, San Francisco, San Francisco
| | - Jill L Ostrem
- From the Movement Disorders and Neuromodulation Center, Department of Neurology, Weill Institute for Neuroscience, University of California, San Francisco, San Francisco
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Kang IH, Bega D. The Impact of Drug Interactions on the Results of DAT-SPECT Imaging in a Specialty Movement Disorders Practice: A Retrospective Analysis of Outcomes. NEURODEGENER DIS 2024; 24:91-96. [PMID: 38952120 DOI: 10.1159/000540105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 06/27/2024] [Indexed: 07/03/2024] Open
Abstract
INTRODUCTION DAT-SPECT imaging is approved as a diagnostic tool for the evaluation of suspected Parkinsonian syndromes, but the FDA-approved package insert lists 16 potential drugs that may interfere with the image obtained. The clinical impact of these drugs on imaging results has not been established. This study aimed to determine the accuracy of DAT-SPECT imaging in assessing presynaptic dopaminergic denervation in the setting of these drugs. METHODS This is a retrospective chart review of patients at a single center who underwent DAT-SPECT imaging while taking "contraindicated" drugs between December 2012 and December 2022. RESULTS A total of 1,224 charts were screened, and 153 (12.5%) charts met the inclusion criteria. Bupropion (32%, n = 49) and sertraline (26%, n = 40) were the most common contraindicated drugs. The false-positive rate was 9.2%. CONCLUSION This retrospective analysis supports the concern that certain drugs may interfere with DAT-SPECT imaging results, leading to potential false positives. This has implications for how clinicians interpret DAT-SPECT imaging in patients taking these medications and whether they should advise patients to stop these medications before a scan is performed.
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Affiliation(s)
| | - Danny Bega
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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3
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Bougea A. Digital biomarkers in Parkinson's disease. Adv Clin Chem 2024; 123:221-253. [PMID: 39181623 DOI: 10.1016/bs.acc.2024.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Digital biomarker (DB) assessments provide objective measures of daily life tasks and thus hold promise to improve diagnosis and monitoring of Parkinson's disease (PD) patients especially those with advanced stages. Data from DB studies can be used in advanced analytics such as Artificial Intelligence and Machine Learning to improve monitoring, treatment and outcomes. Although early development of inertial sensors as accelerometers and gyroscopes in smartphones provided encouraging results, the use of DB remains limited due to lack of standards, harmonization and consensus for analytical as well as clinical validation. Accordingly, a number of clinical trials have been developed to evaluate the performance of DB vs traditional assessment tools with the goal of monitoring disease progression, improving quality of life and outcomes. Herein, we update current evidence on the use of DB in PD and highlight potential benefits and limitations and provide suggestions for future research study.
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Affiliation(s)
- Anastasia Bougea
- Department of Neurology, Medical School, Aeginition Hospital, National and Kapodistrian University of Athens, Athens, Greece.
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Quintas S, Sanles‐Falagan R, Berbís MÁ. I 123-FP-CIT (DaTSCAN) SPECT beyond the Most Common Causes of Parkinsonism: A Systematic Review. Mov Disord Clin Pract 2024; 11:613-625. [PMID: 38693679 PMCID: PMC11145110 DOI: 10.1002/mdc3.14055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/23/2024] [Accepted: 03/30/2024] [Indexed: 05/03/2024] Open
Abstract
BACKGROUND As the diagnosis of Parkinson's disease (PD) is fundamentally clinical, the usefulness of ioflupane (123I) single-photon emission computed tomography (SPECT) or DaTSCAN as a diagnostic tool has been a matter of debate for years. The performance of DaTSCAN is generally recommended in the follow-up of patients with a clinically uncertain diagnosis, especially in those with a suspected essential tremor, drug-induced parkinsonism, or vascular parkinsonism. However, there is a dearth of DaTSCAN findings regarding neurodegenerative parkinsonisms besides PD and atypical parkinsonisms. To date, a specific nigrostriatal dopamine uptake pattern that would help differentiate PD from the most frequent atypical parkinsonisms is yet to be described. This fact is further complicated by the possible visualization of abnormalities in the uptake pattern in patients with rarer neurodegenerative parkinsonisms. OBJECTIVES We aimed to summarize the current literature regarding DaTSCAN findings in patients with rare neurodegenerative parkinsonisms. METHODS The PubMed database was systematically screened for studies in English or Spanish up to October 15, 2023, using search terms "DaTSCAN", "ioflupane", "DaT-SPECT", "123I-FP-CIT SPECT", "dopamine transporter imaging", and "[123I] FP-CIT SPECT". Duplicated publications and studies regarding PD, atypical parkinsonisms, dystonia-parkinsonism, essential tremor, and parkinsonism due to non-degenerative causes were excluded. RESULTS The obtained results were reviewed and summarized, including DaTSCAN findings in fragile X-associated tremor/ataxia syndrome, prion diseases, Huntington's disease, spinocerebellar ataxia, hereditary spastic paraparesis, metabolic disorders, and other diseases (anti-IgLON5 disease, ring chromosome 20 syndrome, chorea-acanthocytosis, and neuronal ceroid lipofuscinosis). CONCLUSIONS This review highlights the need to determine in the future the utility and cost-effectiveness of DaTSCAN, both as a diagnostic and a prognostic tool, in patients with parkinsonian symptoms in rare neurodegenerative diseases.
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Affiliation(s)
- Sonia Quintas
- Department of NeurologyLa Princesa University HospitalMadridSpain
| | | | - M. Álvaro Berbís
- Department of RadiologyHT Médica, San Juan de Dios HospitalCórdobaSpain
- Faculty of MedicineAutonomous University of MadridMadridSpain
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Khosousi S, Sturchio A, Appleton E, Paslawski W, Ta M, Nalls M, Singleton AB, Iwaki H, Svenningsson P. Increased CSF DOPA Decarboxylase Correlates with Lower DaT-SPECT Binding: Analyses in Biopark and PPMI Cohorts. Mov Disord 2024. [PMID: 38798037 DOI: 10.1002/mds.29835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/15/2024] [Accepted: 05/01/2024] [Indexed: 05/29/2024] Open
Abstract
BACKGROUND Recent studies identified increased cerebrospinal fluid (CSF) DOPA decarboxylase (DDC) as a promising biomarker for parkinsonian disorders, suggesting a compensation to dying dopaminergic neurons. A correlation with 123I-FP-CIT-SPECT (DaT-SPECT) imaging could shed light on this link. OBJECTIVE The objective is to assess the relationship between CSF DDC levels and DaT-SPECT binding values. METHODS A total of 51 and 72 Parkinson's disease (PD) subjects with available DaT-SPECT and CSF DDC levels were selected from the PPMI and Biopark cohorts, respectively. DDC levels were analyzed using proximity extension assay and correlated with DaT-SPECT striatal binding ratios (SBR). All analyses were corrected for age and sex. RESULTS CSF DDC levels in PD patients correlated negatively with DaT-SPECT SBR in both putamen and caudate nucleus. Additionally, SBR decreased with increased DDC levels over time in PD patients. CONCLUSION CSF DDC levels negatively correlate with DaT-SPECT SBR in levodopa-treated PD. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Shervin Khosousi
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Sturchio
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- James J. and Joan A. Gardner Family Center for Parkinson's Disease and Movement Disorders, Department of Neurology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Ellen Appleton
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Wojciech Paslawski
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Michael Ta
- Center for Alzheimer's and Related Dementias, National Institute on Aging and National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- DataTecnica LLC, Washington, District of Columbia, USA
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Michael Nalls
- Center for Alzheimer's and Related Dementias, National Institute on Aging and National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- DataTecnica LLC, Washington, District of Columbia, USA
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Andrew B Singleton
- Center for Alzheimer's and Related Dementias, National Institute on Aging and National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Hirotaka Iwaki
- Center for Alzheimer's and Related Dementias, National Institute on Aging and National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- DataTecnica LLC, Washington, District of Columbia, USA
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Per Svenningsson
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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O’Shea DM, Arkhipenko A, Galasko D, Goldman JG, Sheikh ZH, Petrides G, Toledo JB, Galvin JE. Practical use of DAT SPECT imaging in diagnosing dementia with Lewy bodies: a US perspective of current guidelines and future directions. Front Neurol 2024; 15:1395413. [PMID: 38711561 PMCID: PMC11073567 DOI: 10.3389/fneur.2024.1395413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Accepted: 03/25/2024] [Indexed: 05/08/2024] Open
Abstract
Background Diagnosing Dementia with Lewy Bodies (DLB) remains a challenge in clinical practice. The use of 123I-ioflupane (DaTscan™) SPECT imaging, which detects reduced dopamine transporter (DAT) uptake-a key biomarker in DLB diagnosis-could improve diagnostic accuracy. However, DAT imaging is underutilized despite its potential, contributing to delays and suboptimal patient management. Methods This review evaluates DLB diagnostic practices and challenges faced within the U.S. by synthesizing information from current literature, consensus guidelines, expert opinions, and recent updates on DaTscan FDA filings. It contrasts DAT SPECT with alternative biomarkers, provides recommendations for when DAT SPECT imaging may be indicated and discusses the potential of emerging biomarkers in enhancing diagnostic approaches. Results The radiopharmaceutical 123I-ioflupane for SPECT imaging was initially approved in Europe (2000) and later in the US (2011) for Parkinsonism/Essential Tremor. Its application was extended in 2022 to include the diagnosis of DLB. DaTscan's diagnostic efficacy for DLB, with its sensitivity, specificity, and predictive values, confirms its clinical utility. However, US implementation faces challenges such as insurance barriers, costs, access issues, and regional availability disparities. Conclusion 123I-ioflupane SPECT Imaging is indicated for DLB diagnosis and differential diagnosis of Alzheimer's Disease, particularly in uncertain cases. Addressing diagnostic obstacles and enhancing physician-patient education could improve and expedite DLB diagnosis. Collaborative efforts among neurologists, geriatric psychiatrists, psychologists, and memory clinic staff are key to increasing diagnostic accuracy and care in DLB management.
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Affiliation(s)
- Deirdre M. O’Shea
- Department of Neurology, Comprehensive Center for Brain Health, University of Miami, Miller School of Medicine, Coral Gables, FL, United States
| | | | - Douglas Galasko
- Department of Neurosciences, UC San Diego, San Diego, CA, United States
| | - Jennifer G. Goldman
- JPG Enterprises LLC, Chicago, IL, United States
- Barrow Neurological Institute, Phoenix, AZ, United States
| | | | - George Petrides
- Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Jon B. Toledo
- Nantz National Alzheimer Center, Stanley Appel Department of Neurology, Houston Methodist Hospital, Houston, TX, United States
| | - James E. Galvin
- Department of Neurology, Comprehensive Center for Brain Health, University of Miami, Miller School of Medicine, Coral Gables, FL, United States
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Buchert R, Szabo B, Kovacs A, Buddenkotte T, Mathies F, Karimzadeh A, Lehnert W, Klutmann S, Forgacs A, Apostolova I. Dopamine Transporter SPECT with 12-Minute Scan Duration Using Multiple-Pinhole Collimators. J Nucl Med 2024; 65:446-452. [PMID: 38238040 DOI: 10.2967/jnumed.123.266276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 11/28/2023] [Indexed: 03/03/2024] Open
Abstract
This study evaluated the potential to reduce the scan duration in dopamine transporter (DAT) SPECT when using a second-generation multiple-pinhole (MPH) collimator designed for brain SPECT with improved count sensitivity and improved spatial resolution compared with parallel-hole and fanbeam collimators. Methods: The retrospective study included 640 consecutive clinical DAT SPECT studies that had been acquired in list mode with a triple-head SPECT system with MPH collimators and a 30-min net scan duration after injection of 181 ± 10 MBq of [123I]FP-CIT. Raw data corresponding to scan durations of 20, 15, 12, 8, 6, and 4 min were obtained by restricting the events to a proportionally reduced time interval of the list-mode data for each projection angle. SPECT images were reconstructed iteratively with the same parameter settings irrespective of scan duration. The resulting 5,120 SPECT images were assessed for a neurodegeneration-typical reduction in striatal signal by visual assessment, conventional specific binding ratio analysis, and a deep convolutional neural network trained on 30-min scans. Results: Regarding visual interpretation, image quality was considered diagnostic for all 640 patients down to a 12-min scan duration. The proportion of discrepant visual interpretations between 30 and 12 min (1.2%) was not larger than the proportion of discrepant visual interpretations between 2 reading sessions of the same reader at a 30-min scan duration (1.5%). Agreement with the putamen specific binding ratio from the 30-min images was better than expected for 5% test-retest variability down to a 10-min scan duration. A relevant change in convolutional neural network-based automatic classification was observed at a 6-min scan duration or less. Conclusion: The triple-head SPECT system with MPH collimators allows reliable DAT SPECT after administration of about 180 MBq of [123I]FP-CIT with a 12-min scan duration.
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Affiliation(s)
- Ralph Buchert
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Balazs Szabo
- Mediso Medical Imaging Systems, Budapest, Hungary
| | - Akos Kovacs
- Mediso Medical Imaging Systems, Budapest, Hungary
| | - Thomas Buddenkotte
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Franziska Mathies
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Amir Karimzadeh
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Wencke Lehnert
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Susanne Klutmann
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | | | - Ivayla Apostolova
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
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Mercer MK, Revels JW, Blacklock LC, Banks KP, Johnson LS, Lewis DH, Kuo PH, Wilson S, Elojeimy S. Practical Overview of 123I-Ioflupane Imaging in Parkinsonian Syndromes. Radiographics 2024; 44:e230133. [PMID: 38236751 DOI: 10.1148/rg.230133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
Parkinsonian syndromes are a heterogeneous group of progressive neurodegenerative disorders involving the nigrostriatal dopaminergic pathway and are characterized by a wide spectrum of motor and nonmotor symptoms. These syndromes are quite common and can profoundly impact the lives of patients and their families. In addition to classic Parkinson disease, parkinsonian syndromes include multiple additional disorders known collectively as Parkinson-plus syndromes or atypical parkinsonism. These are characterized by the classic parkinsonian motor symptoms with additional distinguishing clinical features. Dopamine transporter SPECT has been developed as a diagnostic tool to assess the levels of dopamine transporters in the striatum. This imaging assessment, which uses iodine 123 (123I) ioflupane, can be useful to differentiate parkinsonian syndromes caused by nigrostriatal degeneration from other clinical mimics such as essential tremor or psychogenic tremor. Dopamine transporter imaging plays a crucial role in diagnosing parkinsonian syndromes, particularly in patients who do not clearly fulfill the clinical criteria for diagnosis. Diagnostic clarification can allow early treatment in appropriate patients and avoid misdiagnosis. At present, only the qualitative interpretation of dopamine transporter SPECT is approved by the U.S. Food and Drug Administration, but quantitative interpretation is often used to supplement qualitative interpretation. The authors provide an overview of patient preparation, common imaging findings, and potential pitfalls that radiologists and nuclear medicine physicians should know when performing and interpreting dopamine transporter examinations. Alternatives to 123I-ioflupane imaging for the evaluation of nigrostriatal degeneration are also briefly discussed. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Intenzo and Colarossi in this issue.
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Affiliation(s)
- Megan K Mercer
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Jonathan W Revels
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Lisa C Blacklock
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Kevin P Banks
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Lester S Johnson
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - David H Lewis
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Phillip H Kuo
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Shannon Wilson
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
| | - Saeed Elojeimy
- From the Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, CSB 211N, MSC 323, Charleston, SC 29425 (M.K.M., S.E.); Department of Radiology, New York University Langone Health Long Island, New York, NY (J.W.R.); Department of Radiology, University of New Mexico, Albuquerque, NM (L.C.B.); Department of Radiology, Brooke Army Medical Center, San Antonio, Tex (K.P.B.); Department of Radiology, Eastern Virginia Medical School, Norfolk, Va (L.S.J., S.W.); Department of Radiology, University of Washington, Seattle, Wash (D.H.L.); and Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Ariz (P.H.K.)
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Pike SC, Havrda M, Gilli F, Zhang Z, Salas LA. Immunological shifts during early-stage Parkinson's disease identified with DNA methylation data on longitudinally collected blood samples. NPJ Parkinsons Dis 2024; 10:21. [PMID: 38212355 PMCID: PMC10784484 DOI: 10.1038/s41531-023-00626-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 12/18/2023] [Indexed: 01/13/2024] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease in the United States. Decades before motor symptoms manifest, non-motor symptoms such as hyposmia and rapid eye movement (REM) sleep behavior disorder are highly predictive of PD. Previous immune profiling studies have identified alterations to the proportions of immune cells in the blood of clinically defined PD patients. However, it remains unclear if these phenotypes manifest before the clinical diagnosis of PD. We utilized longitudinal DNA methylation (DNAm) microarray data from the Parkinson's Progression Marker's Initiative (PPMI) to perform immune profiling in clinically defined PD and prodromal PD patients (Prod). We identified previously reported changes in neutrophil, monocyte, and T cell numbers in PD patients. Additionally, we noted previously unrecognized decreases in the naive B cell compartment in the defined PD and Prod patient group. Over time, we observed the proportion of innate immune cells in PD blood increased, but the proportion of adaptive immune cells decreased. We identified decreases in T and B cell subsets associated with REM sleep disturbances and early cognitive decline. Lastly, we identified increases in B memory cells associated with both genetic (LRRK2 genotype) and infectious (cytomegalovirus seropositivity) risk factors of PD. Our analysis shows that the peripheral immune system is dynamic as the disease progresses. The study provides a platform to understand how and when peripheral immune alterations occur in PD and whether intervention at particular stages may be therapeutically advantageous.
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Affiliation(s)
- Steven C Pike
- Integrative Neuroscience at Dartmouth, Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, NH, USA.
- Department of Epidemiology, Geisel School of Medicine at Dartmouth College, Lebanon, NH, USA.
- Department of Neurology, Dartmouth Hitchcock Medical Center, Lebanon, NH, USA.
| | - Matthew Havrda
- Integrative Neuroscience at Dartmouth, Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, NH, USA
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA
| | - Francesca Gilli
- Integrative Neuroscience at Dartmouth, Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, NH, USA
- Department of Neurology, Dartmouth Hitchcock Medical Center, Lebanon, NH, USA
| | - Ze Zhang
- Department of Epidemiology, Geisel School of Medicine at Dartmouth College, Lebanon, NH, USA
| | - Lucas A Salas
- Integrative Neuroscience at Dartmouth, Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, NH, USA.
- Department of Epidemiology, Geisel School of Medicine at Dartmouth College, Lebanon, NH, USA.
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Middleton JS, Hovren HL, Kha N, Medina MJ, MacLeod KR, Concha-Marambio L, Jensen KJ. Seed amplification assay results illustrate discrepancy in Parkinson's disease clinical diagnostic accuracy and error rates. J Neurol 2023; 270:5813-5818. [PMID: 37592136 PMCID: PMC10632284 DOI: 10.1007/s00415-023-11810-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 05/26/2023] [Accepted: 06/07/2023] [Indexed: 08/19/2023]
Abstract
Parkinson's disease (PD) may be misdiagnosed due to the clinical overlap between PD and atypical parkinsonism. The utility of α-Synuclein (αSyn) Seed Amplification Assay (SAA) as a diagnostic indicator for PD has been reported in numerous studies, but never when administered as a validated clinical laboratory test. This study compares results from αSyn-SAA validation testing performed using well-characterized cohorts from two biorepositories to better understand the accuracy of PD clinical diagnosis. Blinded cerebrospinal fluid (CSF) specimens from a repository that included cohorts of subjects clinically diagnosed as PD or healthy controls, both with confirmatory dopamine transporter single-photon emission computed tomography (DAT SPECT) imaging, and blinded CSF specimens from a repository that included cohorts of subjects clinically diagnosed as PD or healthy controls based on clinical diagnosis alone, were tested as part of the validation studies for the diagnostic αSyn-SAA test (SYNTap® Biomarker Test). Measured αSyn-SAA test accuracy was 83.9% using clinical diagnosis as comparator, and 93.6% using clinical diagnosis with confirmatory DAT- SPECT imaging as comparator. The statistically significant discordance between accuracy determinations using specimens classified using different diagnostic inclusion criteria indicates that there is some symbiosis between dopamine-weighted imaging and αSyn-SAA results, both of which are associated with higher accuracy compared with the clinical diagnosis alone.
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Affiliation(s)
| | | | - Nelson Kha
- Clinical Laboratory, Amprion Inc, San Diego, CA, USA
| | | | | | - Luis Concha-Marambio
- Research Laboratory, Amprion Inc, 10355 Science Center Drive, San Diego, CA, 92121, USA
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11
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Peng H, Chen S, Wu S, Shi X, Ma J, Yang H, Li X. Alpha-synuclein in skin as a high-quality biomarker for Parkinson's disease. J Neurol Sci 2023; 451:120730. [PMID: 37454572 DOI: 10.1016/j.jns.2023.120730] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/04/2023] [Accepted: 07/06/2023] [Indexed: 07/18/2023]
Abstract
Parkinson's disease (PD), the most common neurological motor system disorder, which characterised by the irreversible loss of dopaminergic neurones in the substantia nigra pars compacta, and leads to the deficiency of dopamine in the striatum. Deposited Lewy bodies (LBs) in diseased neurones and nerve terminals are the pathological hallmark of PD, and alpha-synuclein (α-Syn) is the most prominent protein in LBs. The tight association between α-Syn and the molecular pathology of PD has generatly increaed the interest in using the α-Syn species as biomarkers to diagnose early PD. α-Syn is not confined to the central nervous system, it is also present in the peripheral tissues, such as human skin. The assessment of skin α-Syn has the potential to be a diagnostic method that not only has excellent sensitivity, specificity, and reproducibility, but also convenient and acceptable to patients. In this review, we (i) integrate the biochemical, aggregation and structural features of α-Syn; (ii) map the distribution of the α-Syn species present in the brain, biological fluids, and peripheral tissues; and (iii) present a critical and comparative analysis of previous studies that have measured α-Syn in the skin. Finally, we provide an outlook on the future of skin biopsy as a diagnostic approach for PD, and highlight its potential implications for clinical trials, clinical decision-making, treatment strategies as well as the development of new therapies.
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Affiliation(s)
- Haoran Peng
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China
| | - Siyuan Chen
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China
| | - Shaopu Wu
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China
| | - Xiaoxue Shi
- Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China
| | - Jianjun Ma
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China
| | - Hongqi Yang
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China
| | - Xue Li
- Department of Neurology, People's Hospital of Henan University, Zhengzhou, Henan 450003, China; Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China; Department of Neurology, People's Hospital of Zheng Zhou University, Zhengzhou, Henan 450003, China.
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12
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Chahid Y, Sheikh ZH, Mitropoulos M, Booij J. A systematic review of the potential effects of medications and drugs of abuse on dopamine transporter imaging using [ 123I]I-FP-CIT SPECT in routine practice. Eur J Nucl Med Mol Imaging 2023; 50:1974-1987. [PMID: 36847827 PMCID: PMC10199883 DOI: 10.1007/s00259-023-06171-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 02/18/2023] [Indexed: 03/01/2023]
Abstract
PURPOSE In routine practice, dopamine transporter (DAT) imaging is frequently used as a diagnostic tool to support the diagnosis of Parkinson's disease or dementia with Lewy bodies. In 2008, we published a review on which medications and drugs of abuse may influence striatal [123I]I-FP-CIT binding and consequently may influence the visual read of an [123I]I-FP-CIT SPECT scan. We made recommendations on which drugs should be withdrawn before performing DAT imaging in routine practice. Here, we provide an update of the original work based on published research since 2008. METHODS We performed a systematic review of literature without language restriction from January 2008 until November 2022 to evaluate the possible effects of medications and drugs of abuse, including the use of tobacco and alcohol, on striatal DAT binding in humans. RESULTS The systematic literature search identified 838 unique publications, of which 44 clinical studies were selected. Using this approach, we found additional evidence to support our original recommendations as well as some new findings on potential effect of other medications on striatal DAT binding. Consequently, we updated the list of medications and drugs of abuse that may influence the visual read of [123I]I-FP-CIT SPECT scans in routine clinical practice. CONCLUSION We expect that a timely withdrawal of these medications and drugs of abuse before DAT imaging may reduce the incidence of false-positive reporting. Nevertheless, the decision to withdraw any medication must be made by the specialist in charge of the patient's care and considering the pros and cons of doing so.
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Affiliation(s)
- Youssef Chahid
- Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, The Netherlands.
- Amsterdam UMC location University of Amsterdam, Clinical Pharmacy, Meibergdreef 9, Amsterdam, The Netherlands.
| | - Zulfiqar H Sheikh
- GE Healthcare, Pharmaceutical Diagnostics, Nightingales Ln, Chalfont Saint Giles, United Kingdom
| | - Max Mitropoulos
- GE Healthcare, Pharmaceutical Diagnostics, Nightingales Ln, Chalfont Saint Giles, United Kingdom
| | - Jan Booij
- Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, The Netherlands
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13
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Apostolova I, Schiebler T, Lange C, Mathies FL, Lehnert W, Klutmann S, Buchert R. Stereotactical normalization with multiple templates representative of normal and Parkinson-typical reduction of striatal uptake improves the discriminative power of automatic semi-quantitative analysis in dopamine transporter SPECT. EJNMMI Phys 2023; 10:25. [PMID: 36991245 DOI: 10.1186/s40658-023-00544-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 03/14/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND The specific binding ratio (SBR) of 123I-FP-CIT in the putamen is widely used to support the interpretation of dopamine transporter (DAT) SPECT. Automatic methods for computation of the putamen SBR often include stereotactical normalization of the individual DAT-SPECT image to an anatomical standard space. This study compared using a single 123I-FP-CIT template image as target for stereotactical normalization versus multiple templates representative of normal and different levels of Parkinson-typical reduction of striatal 123I-FP-CIT uptake. METHODS 1702 clinical 123I-FP-CIT SPECT images were stereotactically normalized (affine) to the anatomical space of the Montreal Neurological Institute (MNI) with SPM12 either using a single custom-made 123I-FP-CIT template representative of normal striatal uptake or using eight different templates representative of normal and different levels of Parkinson-typical reduction of striatal FP-CIT uptake with and without attenuation and scatter correction. In the latter case, SPM finds the linear combination of the multiple templates that best matches the patient's image. The putamen SBR was obtained using hottest voxels analysis in large unilateral regions-of-interest predefined in MNI space. The histogram of the putamen SBR in the whole sample was fitted by the sum of two Gaussians. The power to differentiate between reduced and normal SBR was estimated by the effect size of the distance between the two Gaussians computed as the differences between their mean values scaled to their pooled standard deviation. RESULTS The effect size of the distance between the two Gaussians was 3.83 with the single template versus 3.96 with multiple templates for stereotactical normalization. CONCLUSIONS Multiple templates representative of normal and different levels of Parkinson-typical reduction for stereotactical normalization of DAT-SPECT might provide improved separation between normal and reduced putamen SBR that could result in slightly improved power for the detection of nigrostriatal degeneration.
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Affiliation(s)
- Ivayla Apostolova
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Tassilo Schiebler
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Catharina Lange
- Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Franziska Lara Mathies
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Wencke Lehnert
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Susanne Klutmann
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Ralph Buchert
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
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14
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Goh YY, Saunders E, Pavey S, Rushton E, Quinn N, Houlden H, Chelban V. Multiple system atrophy. Pract Neurol 2023; 23:208-221. [PMID: 36927875 DOI: 10.1136/pn-2020-002797] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2023] [Indexed: 03/18/2023]
Abstract
This is a practical guide to diagnosing and managing multiple system atrophy (MSA). We explain the newly published Movement Disorders Society Consensus Diagnostic Criteria, which include new 'Clinically Established MSA' and 'Possible Prodromal MSA' categories, hopefully reducing time to diagnosis. We then highlight the key clinical features of MSA to aid diagnosis. We include a list of MSA mimics with suggested methods of differentiation from MSA. Lastly, we discuss practical symptom management in people living with MSA, including balancing side effects, with the ultimate aim of improving quality of life.
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Affiliation(s)
- Yee Yen Goh
- Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | | | | | | | - Niall Quinn
- Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Henry Houlden
- Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Viorica Chelban
- Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK .,Neurobiology and Medical Genetics Laboratory, "Nicolae Testemitanu" State University of Medicine and Pharmacy, Chisinau, Moldova
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15
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Tsang K, Walker R. Dopamine transporter single photon emission computed tomography (DaT-SPECT) use in the diagnosis and clinical management of parkinsonism: an 8-year retrospective study. J Neurol 2023; 270:2550-2558. [PMID: 36795149 PMCID: PMC10129961 DOI: 10.1007/s00415-023-11563-y] [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: 11/21/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 02/17/2023]
Abstract
INTRODUCTION Parkinson's disease (PD) is a neurodegenerative movement disorder that is typically diagnosed clinically. DaT-SPECT scanning (DaT Scan) can be used when there is diagnostic difficulty differentiating from non-neurodegenerative Parkinsonism. This study assessed the effect of DaT Scan imaging on diagnosis and subsequent clinical management of these disorders. METHODS This single-trust retrospective study involved 455 patients who had undergone DaT scans for investigation for Parkinsonism, between 01/01/2014 and 31/12/2021. Data collected included patient demographics, date of clinical assessment, scan report, pre-scan and post-scan diagnosis, and clinical management. RESULTS The mean age at scan was 70.5 years and 57% were male. The percentage of patients who had an abnormal scan result was 40% (n = 184), whilst 53% (n = 239) had a normal scan result, and 7% (n = 32) had an equivocal scan. Pre-scan diagnosis was consistent with scan results in 71% of cases of neurodegenerative Parkinsonism, whereas this figure was 64% for cases of non-neurodegenerative Parkinsonism. For all DaT scans, the diagnosis was changed in 37% of patients (n = 168), whilst the clinical management was changed in 42% of patients (n = 190). Change in management involved 63% starting dopaminergic medication, 5% stopping dopaminergic medications, and 31% undergoing other changes in management. CONCLUSION DaT imaging is useful for confirming the correct diagnosis and clinical management for patients with clinically indeterminate Parkinsonism. Pre-scan diagnoses were generally consistent with scan results.
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Affiliation(s)
- Kaki Tsang
- North Tees and Hartlepool Trust, Stockton-upon-Tees, UK. .,Department of Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK.
| | - Richard Walker
- Department of Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK.,Northumbria Healthcare NHS Foundation Trust, Medicine, North Shields, Tyne and Wear, UK
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16
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Norris SA, Perlmutter JS. The Future of Functional Neuroimaging in Parkinsonism: Prove It! JAMA Neurol 2023; 80:121-122. [PMID: 36374495 PMCID: PMC10645147 DOI: 10.1001/jamaneurol.2022.3978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This Viewpoint discusses the current lack of evidence of functional neuroimaging affecting patient outcomes in parkinsonian conditions.
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Affiliation(s)
- Scott A Norris
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri
| | - Joel S Perlmutter
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri
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Reddy TT, Iguban MH, Melkonyan LL, Shergill J, Liang C, Mukherjee J. Development of [ 124/125I]IAZA as a New Proteinopathy Imaging Agent for Alzheimer's Disease. Molecules 2023; 28:molecules28020865. [PMID: 36677925 PMCID: PMC9863004 DOI: 10.3390/molecules28020865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/08/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Radioiodinated imaging agents for Aβ amyloid plaque imaging in Alzheimer’s disease (AD) patients have not been actively pursued. Our previous studies employed the “diaza” derivatives [11C]TAZA and [18F]flotaza in order to develop successful positron emission tomography (PET) imaging agents for Aβ plaques. There is a need for radioiodinated imaging agents for Aβ plaques for single photon emission computed tomography (SPECT) and PET imaging. We report our findings on the preparation of [124/125I]IAZA, a “diaza” analog of [11C]TAZA and [18F]flotaza, and the evaluation of binding to Aβ plaques in the postmortem human AD brain. The binding affinity of IAZA for Aβ plaques was Ki = 10.9 nM with weak binding affinity for neurofibrillary tangles (Ki = 3.71 μM). Both [125I]IAZA and [124I]IAZA were produced in >25% radiochemical yield and >90% radiochemical purity. In vitro binding of [125I]IAZA and [124I]IAZA in postmortem human AD brains was higher in gray matter containing Aβ plaques compared to white matter (ratio of gray to white matter was >7). Anti-Aβ immunostaining strongly correlated with [124/125I]IAZA in postmortem AD human brains. The binding of [124/125I]IAZA in postmortem human AD brains was displaced by the known Aβ plaque imaging agents. Thus, radiolabeled [124/123I]IAZA may potentially be a useful PET or SPECT radioligand for Aβ plaques in brain imaging studies.
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18
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Lamotte G, Singer W. Synucleinopathies. HANDBOOK OF CLINICAL NEUROLOGY 2023; 196:175-202. [PMID: 37620069 DOI: 10.1016/b978-0-323-98817-9.00032-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
The α-synucleinopathies include pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease. The past two decades have witnessed significant advances in the diagnostic strategies and symptomatic treatment of motor and nonmotor symptoms of the synucleinopathies. This chapter provides an in-depth review of the pathophysiology, pathology, genetic, epidemiology, and clinical and laboratory autonomic features that distinguish the different synucleinopathies with an emphasis on autonomic failure as a common feature. The treatment of the different synucleinopathies is discussed along with the proposal for multidisciplinary, individualized care models that optimally address the various symptoms. There is an urgent need for clinical scientific studies addressing patients at risk of developing synucleinopathies and the investigation of disease mechanisms, biomarkers, potential disease-modifying therapies, and further advancement of symptomatic treatments for motor and nonmotor symptoms.
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Affiliation(s)
- Guillaume Lamotte
- Department of Neurology, University of Utah, Salt Lake City, UT, United States
| | - Wolfgang Singer
- Department of Neurology, Mayo Clinic, Rochester, MN, United States.
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19
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Mathies F, Apostolova I, Dierck L, Jacobi J, Kuen K, Sauer M, Schenk M, Klutmann S, Forgács A, Buchert R. Multiple-pinhole collimators improve intra- and between-rater agreement and the certainty of the visual interpretation in dopamine transporter SPECT. EJNMMI Res 2022; 12:51. [PMID: 35976493 PMCID: PMC9385910 DOI: 10.1186/s13550-022-00923-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/08/2022] [Indexed: 11/10/2022] Open
Abstract
Background Multiple-pinhole (MPH) collimators improve the resolution–sensitivity trade-off compared to parallel-hole collimators. This study evaluated the impact of MPH collimators on intra- and between-rater agreement, and on the certainty of visual interpretation in dopamine transporter (DAT)-SPECT. Methods The study included 71 patients (62.1 ± 12.7 y). Two SPECT acquisitions were performed in randomized order after a single injection of 182 ± 9 MBq 123I-FP-CIT, one with MPH and one with low-energy–high-resolution–high-sensitivity (LEHRHS) collimators. MPH projections were reconstructed with an iterative 3d Monte Carlo algorithm. LEHRHS projections were reconstructed with filtered backprojection (FBP) or with ordered-subsets expectation–maximization and resolution recovery (OSEM). Images were visually evaluated twice by three independent raters with respect to presence/absence of Parkinson-typical reduction of striatal 123I-FP-CIT uptake using a Likert 6-score (− 3 = clearly normal, …, 3 = clearly reduced). In case of intra-rater discrepancy, an intra-rater consensus was obtained. Intra- and between-rater agreement with respect to the Likert score (6-score and dichotomized score) was characterized by Cohen’s kappa. Results Intra-rater kappa of visual scoring of MPH/LEHRHS-OSEM/LEHRHS-FBP images was 0.84 ± 0.12/0.73 ± 0.06/0.73 ± 0.08 (6-score, mean of three raters) and 1.00 ± 0.00/0.96 ± 0.04/0.97 ± 0.03 (dichotomized score). Between-rater kappa of visual scoring (intra-rater consensus) of MPH/LEHRHS-OSEM/LEHRHS-FBP images was 0.70 ± 0.06/0.63 ± 0.08/0.48 ± 0.05 (6-score, mean of three pairs of raters) and 1.00 ± 0.00/0.92 ± 0.04/0.90 ± 0.06 (dichotomized score). There was a decrease of (negative) Likert scores in normal DAT-SPECT by 0.87 ± 0.18 points from the LEHRHS-OSEM to the MPH setting. The (positive) Likert scores of reduced DAT-SPECT did not change on average. Conclusions MPH collimators improve intra- and between-rater agreement as well as the certainty of the visual interpretation of DAT-SPECT. Supplementary Information The online version contains supplementary material available at 10.1186/s13550-022-00923-w.
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Affiliation(s)
- Franziska Mathies
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Ivayla Apostolova
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Lena Dierck
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Janin Jacobi
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Katja Kuen
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Markus Sauer
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Michael Schenk
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Susanne Klutmann
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | | | - Ralph Buchert
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
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20
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Abstract
PURPOSE OF REVIEW This article discusses neuroimaging in dementia diagnosis, with a focus on new applications of MRI and positron emission tomography (PET). RECENT FINDINGS Although the historical use of MRI in dementia diagnosis has been supportive to exclude structural etiologies, recent innovations allow for quantification of atrophy patterns that improve sensitivity for supporting the diagnosis of dementia causes. Neuronuclear approaches allow for localization of specific amyloid and tau neuropathology on PET and are available for clinical use, in addition to dopamine transporter scans in dementia with Lewy bodies and metabolic studies with fludeoxyglucose PET (FDG-PET). SUMMARY Using computerized software programs for MRI analysis and cross-sectional and longitudinal evaluations of hippocampal, ventricular, and lobar volumes improves sensitivity in support of the diagnosis of Alzheimer disease and frontotemporal dementia. MRI protocol requirements for such quantification are three-dimensional T1-weighted volumetric imaging protocols, which may need to be specifically requested. Fluid-attenuated inversion recovery (FLAIR) and 3.0T susceptibility-weighted imaging (SWI) sequences are useful for the detection of white matter hyperintensities as well as microhemorrhages in vascular dementia and cerebral amyloid angiopathy. PET studies for amyloid and/or tau pathology can add additional specificity to the diagnosis but currently remain largely inaccessible outside of research settings because of prohibitive cost constraints in most of the world. Dopamine transporter PET scans can help identify Lewy body dementia and are thus of potential clinical value.
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Affiliation(s)
- Cyrus A. Raji
- Washington University in St. Louis Mallinckrodt Institute of Radiology, Division of Neuroradiology
- Washington University in St. Louis Department of Neurology
- Washington University in St. Louis Neuroimaging Laboratories
- Knight Alzheimer Disease Research Center, Washington University in St. Louis
| | - Tammie L. S. Benzinger
- Washington University in St. Louis Mallinckrodt Institute of Radiology, Division of Neuroradiology
- Washington University in St. Louis Neuroimaging Laboratories
- Knight Alzheimer Disease Research Center, Washington University in St. Louis
- Washington University in St. Louis Department of Neurosurgery
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21
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Wallert ED, van de Giessen E, Knol RJJ, Beudel M, de Bie RMA, Booij J. Imaging Dopaminergic Neurotransmission in Neurodegenerative Disorders. J Nucl Med 2022; 63:27S-32S. [PMID: 35649651 PMCID: PMC9165729 DOI: 10.2967/jnumed.121.263197] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/25/2022] [Indexed: 12/14/2022] Open
Abstract
Imaging of dopaminergic transmission in neurodegenerative disorders such as Parkinson disease (PD) or dementia with Lewy bodies plays a major role in clinical practice and in clinical research. We here review the role of imaging of the nigrostriatal pathway, as well as of striatal receptors and dopamine release, in common neurodegenerative disorders in clinical practice and research. Imaging of the nigrostriatal pathway has a high diagnostic accuracy to detect nigrostriatal degeneration in disorders characterized by nigrostriatal degeneration, such as PD and dementia with Lewy bodies, and disorders of more clinical importance, namely in patients with clinically uncertain parkinsonism. Imaging of striatal dopamine D2/3 receptors is not recommended for the differential diagnosis of parkinsonian disorders in clinical practice anymore. Regarding research, recently the European Medicines Agency has qualified dopamine transporter imaging as an enrichment biomarker for clinical trials in early PD, which underlines the high diagnostic accuracy of this imaging tool and will be implemented in future trials. Also, imaging of the presynaptic dopaminergic system plays a major role in, for example, examining the extent of nigrostriatal degeneration in preclinical and premotor phases of neurodegenerative disorders and to examine subtypes of PD. Also, imaging of postsynaptic dopamine D2/3 receptors plays a role in studying, for example, the neuronal substrate of impulse control disorders in PD, as well as in measuring endogenous dopamine release to examine, for example, motor complications in the treatment of PD. Finally, novel MRI sequences as neuromelanin-sensitive MRI are promising new tools to study nigrostriatal degeneration in vivo.
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Affiliation(s)
- Elon D Wallert
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Elsmarieke van de Giessen
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands
| | - Remco J J Knol
- Department of Nuclear Medicine, Noordwest Ziekenhuisgroep, Alkmaar, The Netherlands; and
| | - Martijn Beudel
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Rob M A de Bie
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Booij
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands;
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The potential convergence of NLRP3 inflammasome, potassium, and dopamine mechanisms in Parkinson's disease. NPJ Parkinsons Dis 2022; 8:32. [PMID: 35332154 PMCID: PMC8948240 DOI: 10.1038/s41531-022-00293-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 02/17/2022] [Indexed: 12/21/2022] Open
Abstract
The pathology of Parkinson's disease (PD) is characterized by α-synuclein aggregation, microglia-mediated neuroinflammation, and dopaminergic neurodegeneration in the substantia nigra with collateral striatal dopamine signaling deficiency. Microglial NLRP3 inflammasome activation has been linked independently to each of these facets of PD pathology. The voltage-gated potassium channel Kv1.3, upregulated in microglia by α-synuclein and facilitating potassium efflux, has also been identified as a modulator of neuroinflammation and neurodegeneration in models of PD. Evidence increasingly suggests that microglial Kv1.3 is mechanistically coupled with NLRP3 inflammasome activation, which is contingent on potassium efflux. Potassium conductance also influences dopamine release from midbrain dopaminergic neurons. Dopamine, in turn, has been shown to inhibit NLRP3 inflammasome activation in microglia. In this review, we provide a literature framework for a hypothesis in which Kv1.3 activity-induced NLRP3 inflammasome activation, evoked by stimuli such as α-synuclein, could lead to microglia utilizing dopamine from adjacent dopaminergic neurons to counteract this process and fend off an activated state. If this is the case, a sufficient dopamine supply would ensure that microglia remain under control, but as dopamine is gradually siphoned from the neurons by microglial demand, NLRP3 inflammasome activation and Kv1.3 activity would progressively intensify to promote each of the three major facets of PD pathology: α-synuclein aggregation, microglia-mediated neuroinflammation, and dopaminergic neurodegeneration. Risk factors overlapping to varying degrees to render brain regions susceptible to such a mechanism would include a high density of microglia, an initially sufficient supply of dopamine, and poor insulation of the dopaminergic neurons by myelin.
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Mining imaging and clinical data with machine learning approaches for the diagnosis and early detection of Parkinson's disease. NPJ Parkinsons Dis 2022; 8:13. [PMID: 35064123 PMCID: PMC8783003 DOI: 10.1038/s41531-021-00266-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 12/10/2021] [Indexed: 12/14/2022] Open
Abstract
Parkinson’s disease (PD) is a common, progressive, and currently incurable neurodegenerative movement disorder. The diagnosis of PD is challenging, especially in the differential diagnosis of parkinsonism and in early PD detection. Due to the advantages of machine learning such as learning complex data patterns and making inferences for individuals, machine-learning techniques have been increasingly applied to the diagnosis of PD, and have shown some promising results. Machine-learning-based imaging applications have made it possible to help differentiate parkinsonism and detect PD at early stages automatically in a number of neuroimaging studies. Comparative studies have shown that machine-learning-based SPECT image analysis applications in PD have outperformed conventional semi-quantitative analysis in detecting PD-associated dopaminergic degeneration, performed comparably well as experts’ visual inspection, and helped improve PD diagnostic accuracy of radiologists. Using combined multi-modal (imaging and clinical) data in these applications may further enhance PD diagnosis and early detection. To integrate machine-learning-based diagnostic applications into clinical systems, further validation and optimization of these applications are needed to make them accurate and reliable. It is anticipated that machine-learning techniques will further help improve differential diagnosis of parkinsonism and early detection of PD, which may reduce the error rate of PD diagnosis and help detect PD at pre-motor stage to make it possible for early treatments (e.g., neuroprotective treatment) to slow down PD progression, prevent severe motor symptoms from emerging, and relieve patients from suffering.
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Takahashi S, Mashima K. Neuroprotection and Disease Modification by Astrocytes and Microglia in Parkinson Disease. Antioxidants (Basel) 2022; 11:antiox11010170. [PMID: 35052674 PMCID: PMC8773262 DOI: 10.3390/antiox11010170] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/03/2022] [Accepted: 01/13/2022] [Indexed: 02/07/2023] Open
Abstract
Oxidative stress and neuroinflammation are common bases for disease onset and progression in many neurodegenerative diseases. In Parkinson disease, which is characterized by the degeneration of dopaminergic neurons resulting in dopamine depletion, the pathogenesis differs between hereditary and solitary disease forms and is often unclear. In addition to the pathogenicity of alpha-synuclein as a pathological disease marker, the involvement of dopamine itself and its interactions with glial cells (astrocyte or microglia) have attracted attention. Pacemaking activity, which is a hallmark of dopaminergic neurons, is essential for the homeostatic maintenance of adequate dopamine concentrations in the synaptic cleft, but it imposes a burden on mitochondrial oxidative glucose metabolism, leading to reactive oxygen species production. Astrocytes provide endogenous neuroprotection to the brain by producing and releasing antioxidants in response to oxidative stress. Additionally, the protective function of astrocytes can be modified by microglia. Some types of microglia themselves are thought to exacerbate Parkinson disease by releasing pro-inflammatory factors (M1 microglia). Although these inflammatory microglia may further trigger the inflammatory conversion of astrocytes, microglia may induce astrocytic neuroprotective effects (A2 astrocytes) simultaneously. Interestingly, both astrocytes and microglia express dopamine receptors, which are upregulated in the presence of neuroinflammation. The anti-inflammatory effects of dopamine receptor stimulation are also attracting attention because the functions of astrocytes and microglia are greatly affected by both dopamine depletion and therapeutic dopamine replacement in Parkinson disease. In this review article, we will focus on the antioxidative and anti-inflammatory effects of astrocytes and their synergism with microglia and dopamine.
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Affiliation(s)
- Shinichi Takahashi
- Department of Neurology and Stroke, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka-shi 350-1298, Japan
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
- Correspondence: ; Tel.: +81-42-984-4111 (ext. 7412); Fax: +81-42-984-0664
| | - Kyoko Mashima
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
- Department of Neurology, Tokyo Saiseikai Central Hospital, 1-4-17 Mita, Minato-ku, Tokyo 108-0073, Japan
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25
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Neill M, Fisher JM, Brand C, Lei H, Sherman SJ, Chou YH, Kuo PH. Practical Application of DaTQUANT with Optimal Threshold for Diagnostic Accuracy of Dopamine Transporter SPECT. Tomography 2021; 7:980-989. [PMID: 34941653 PMCID: PMC8706562 DOI: 10.3390/tomography7040081] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/28/2021] [Accepted: 12/10/2021] [Indexed: 12/11/2022] Open
Abstract
Evaluation of Parkinsonian Syndromes (PS) with Ioflupane iodine-123 dopamine transporter single photon emission computed tomography (DaT-SPECT), in conjunction with history and clinical examination, aids in diagnosis. FDA-approved, semi-quantitative software, DaTQUANTTM (GE Healthcare, Chicago, IL, USA) is available to assist in interpretation. This study aims to evaluate the optimal variables and thresholds of DaTQUANT to yield the optimal diagnostic accuracy. It is a retrospective review with three different patient populations. DaT-SPECT images from all three study groups were evaluated using DaTQUANTTM software, and both single and multi-variable logistic regression were used to model PS status. The optimal models were chosen via accuracy, sensitivity, and specificity, then evaluated on the other study groups. Among single variable models, the posterior putamen yielded the highest accuracy (84% to 95%), while balancing sensitivity and specificity. Multi-variable models did not substantially improve the accuracy. When the optimal single variable models for each group were used to evaluate the remaining two groups, comparable results were achieved. In typical utilization of DaT-SPECT for differentiation between nigrostriatal degenerative disease (NSDD) and non-NSDD, the posterior putamen was the single variable that yielded the highest accuracy across three different patient populations. The posterior putamen’s recommended thresholds for DaTQUANT are SBR ≤ 1.0, z-score of ≤−1.8 and percent deviation ≤ −0.34.
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Affiliation(s)
- Matthew Neill
- Department of Medical Imaging, University of Arizona, Tucson, AZ 85724, USA;
| | - Julia M. Fisher
- Statistics Consulting Laboratory, BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA;
| | | | - Hong Lei
- Department of Neurology, University of Arizona, Tucson, AZ 85724, USA; (H.L.); (S.J.S.)
| | - Scott J. Sherman
- Department of Neurology, University of Arizona, Tucson, AZ 85724, USA; (H.L.); (S.J.S.)
| | - Ying-Hui Chou
- Department of Psychology, University of Arizona, Tucson, AZ 85721, USA;
| | - Phillip H. Kuo
- Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, AZ 85724, USA
- Correspondence:
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26
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Palermo G, Giannoni S, Bellini G, Siciliano G, Ceravolo R. Dopamine Transporter Imaging, Current Status of a Potential Biomarker: A Comprehensive Review. Int J Mol Sci 2021; 22:11234. [PMID: 34681899 PMCID: PMC8538800 DOI: 10.3390/ijms222011234] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 10/12/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022] Open
Abstract
A major goal of current clinical research in Parkinson's disease (PD) is the validation and standardization of biomarkers enabling early diagnosis, predicting outcomes, understanding PD pathophysiology, and demonstrating target engagement in clinical trials. Molecular imaging with specific dopamine-related tracers offers a practical indirect imaging biomarker of PD, serving as a powerful tool to assess the status of presynaptic nigrostriatal terminals. In this review we provide an update on the dopamine transporter (DAT) imaging in PD and translate recent findings to potentially valuable clinical practice applications. The role of DAT imaging as diagnostic, preclinical and predictive biomarker is discussed, especially in view of recent evidence questioning the incontrovertible correlation between striatal DAT binding and nigral cell or axon counts.
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Affiliation(s)
- Giovanni Palermo
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; (G.P.); (S.G.); (G.B.); (G.S.)
| | - Sara Giannoni
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; (G.P.); (S.G.); (G.B.); (G.S.)
- Unit of Neurology, San Giuseppe Hospital, 50053 Empoli, Italy
| | - Gabriele Bellini
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; (G.P.); (S.G.); (G.B.); (G.S.)
| | - Gabriele Siciliano
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; (G.P.); (S.G.); (G.B.); (G.S.)
| | - Roberto Ceravolo
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; (G.P.); (S.G.); (G.B.); (G.S.)
- Center for Neurodegenerative Diseases, Unit of Neurology, Parkinson’s Disease and Movement Disorders, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
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