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Wang LL, Thompson TA, Shih RY, Ajam AA, Bulsara K, Burns J, Davis MA, Ivanidze J, Kalnins A, Kuo PH, Ledbetter LN, Pannell JS, Pollock JM, Shakkottai VG, Shih RD, Soares BP, Soderlund KA, Utukuri PS, Woolsey S, Policeni B. ACR Appropriateness Criteria® Dizziness and Ataxia: 2023 Update. J Am Coll Radiol 2024; 21:S100-S125. [PMID: 38823940 DOI: 10.1016/j.jacr.2024.02.018] [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: 02/20/2024] [Accepted: 02/28/2024] [Indexed: 06/03/2024]
Abstract
Diagnostic evaluation of a patient with dizziness or vertigo is complicated by a lack of standardized nomenclature, significant overlap in symptom descriptions, and the subjective nature of the patient's symptoms. Although dizziness is an imprecise term often used by patients to describe a feeling of being off-balance, in many cases dizziness can be subcategorized based on symptomatology as vertigo (false sense of motion or spinning), disequilibrium (imbalance with gait instability), presyncope (nearly fainting or blacking out), or lightheadedness (nonspecific). As such, current diagnostic paradigms focus on timing, triggers, and associated symptoms rather than subjective descriptions of dizziness type. Regardless, these factors complicate the selection of appropriate diagnostic imaging in patients presenting with dizziness or vertigo. This document serves to aid providers in this selection by using a framework of definable clinical variants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.
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Affiliation(s)
- Lily L Wang
- University of Cincinnati Medical Center, Cincinnati, Ohio.
| | - Trevor A Thompson
- Research Author, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Robert Y Shih
- Panel Chair, Uniformed Services University, Bethesda, Maryland
| | | | - Ketan Bulsara
- UCONN Health, University of Connecticut, Farmington, Connecticut, Neurosurgery expert
| | | | - Melissa A Davis
- Yale University School of Medicine, New Haven, Connecticut; Committee on Emergency Radiology-GSER
| | | | | | - Phillip H Kuo
- University of Arizona, Tucson, Arizona; Commission on Nuclear Medicine and Molecular Imaging
| | | | | | | | - Vikram G Shakkottai
- University of Texas Southwestern Medical Center, Dallas, Texas; American Academy of Neurology
| | - Richard D Shih
- Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida; American College of Emergency Physicians
| | - Bruno P Soares
- The University of Vermont Medical Center, Burlington, Vermont
| | | | | | - Sarah Woolsey
- Association for Utah Community Health, Salt Lake City, Utah; American Academy of Family Physicians
| | - Bruno Policeni
- Specialty Chair, University of Iowa Hospitals and Clinics, Iowa City, Iowa
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Tu Y, Li Z, Xiong F, Gao F. Progressive white matter degeneration in patients with spinocerebellar ataxia type 2. Neuroradiology 2024; 66:101-108. [PMID: 38040824 DOI: 10.1007/s00234-023-03260-4] [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: 08/07/2023] [Accepted: 11/23/2023] [Indexed: 12/03/2023]
Abstract
PURPOSE Spinocerebellar ataxia type 2 (SCA2) is a progressive neurodegenerative disorder characterized by cerebellar atrophy. However, studies to elucidate the longitudinal progression of the neuropathology are limited. We sought to identify brain macrostructural and microstructural alterations in patients with SCA2 using fixel-based analysis (FBA) to better understand its distribution patterns and progression. METHODS We enrolled 9 patients with SCA2 and 16 age- and gender-matched controls. Longitudinal clinical and imaging data were collected at baseline, and 3.5 years later. Fiber density (FD), fiber-bundle cross-section (FC), and a combination of FD and FC (FDC) were calculated. The paired t-test was used to examine longitudinal differences. The associations between fixel-based metrics and clinical variables were explored in SCA2 patients. RESULTS At baseline, patients with SCA2 displayed multiple white matter tracts with significantly decreased FD, FC, and FDC in the corticospinal tract, cerebellar peduncles, brainstem, corpus callosum, thalamus, striatum, and prefrontal cortex, compared to controls. Over time, many of these macrostructural and microstructural alterations progressed, manifesting lower FD, FC, and FDC in corticospinal tract, middle cerebellar peduncle, brainstem, striatum, fornix, and cingulum. No significant brain white matter alterations were found in the healthy controls over time. There was no association between the FBA-derived metrics and clinical variables in SCA2. CONCLUSION This study provides evidence of brain macrostructural and microstructural alterations and of progression over time in SCA2. The FBA-derived metrics may serve as potential biomarkers of SCA2 progression.
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Affiliation(s)
- Ye Tu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zheng Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fei Xiong
- Department of Radiology, General Hospital of Central Theater Command, Wuhan, China.
| | - Feng Gao
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
- Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
- Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Zhao J, Zeng W, Huang X, Hu M, Yuan K, Wu C, Qiu H, Chu J. Analysis and hierarchical clustering of infratentorial morphological MRI identifies SCAs phenogroups. J Neurol 2023; 270:4466-4477. [PMID: 37291395 DOI: 10.1007/s00415-023-11792-1] [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: 02/21/2023] [Revised: 05/20/2023] [Accepted: 05/22/2023] [Indexed: 06/10/2023]
Abstract
BACKGROUND Clinical decision-making in spinocerebellar ataxia spectrum diseases (SCAs) has mainly been based on genetic tests, not considering the SCAs' imaging and clinical heterogenicity. OBJECTIVE To identify SCAs phenogroups by analysis and hierarchical clustering of infratentorial morphological MRI for unveiling pathophysiological differences among common SCA subtypes. METHODS We prospectively enrolled 119 (62 women; mean age 37 years) genetically diagnosed SCAs (SCA1 n = 21, SCA2 n = 10, symptomatic SCA3 n = 59, presymptomatic SCA3 n = 22, SCA6 n = 7) and 35 healthy controls (HCs). All patients underwent MRI and detailed neurological and neuropsychology examinations. The width of each cerebellar peduncle (CP) and anteroposterior diameter of the spinal cord and pontine were measured. Twenty-five SCAs patients (15 women; mean age 35 years) were followed for at least a year (17 (15, 24) months), whose MRI and the Scale for the Assessment and Rating of Ataxia (SARA) were collected. RESULTS Infratentorial morphological MRI measurements could significantly discriminate SCAs from HCs, even among SCA subtypes. Two mutually exclusive and clinically distinct phenogroups were identified. Despite similar (CAG)n, phenogroup 1 (n = 66, 55.5%) presented more atrophied infratentorial brain structures and more severe clinical symptoms with older age and earlier age of onset when compared with phenogroup 2. More importantly, all SCA2, most of SCA1 (76%), and symptomatic SCA3 (68%) were classified into phenogroup 1, whereas all SCA6 and all presymptomatic SCA3 were in phenogroup 2. The right middle CP had the highest diagnostic value in predicting phenogroup 2 (AUC = 0.99; P < 0.01) with high specificity (95%). Consistent with the significantly increased SARA (7.5 vs 10, P = 0.021), the bilateral inferior CP, spinal cord, and pontine tegmentum were more atrophy during the follow-up (P < 0.05). CONCLUSION SCAs were with significant infratentorial brain atrophy than HCs. We identified two different SCAs phenogroups associated with substantial differences in infratentorial brain atrophy, clinical presentation, and may reflect the underlying molecular profiles to some extent, paving the way for a more personalized diagnostic and treatment approach.
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Affiliation(s)
- Jing Zhao
- Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, 518000, Guangdong, China
| | - Wenting Zeng
- Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, 518000, Guangdong, China
| | - Xiaolong Huang
- Intensive Care Unit, The First Affiliated Hospital of Xiamen University, Xiamen, 361001, Fujian, China
| | - Manshi Hu
- Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, 518000, Guangdong, China
| | - Kang Yuan
- Sun Yat-Sen University, Guangzhou, 518000, Guangdong, China
| | - Chao Wu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, Guangdong, 518000, China.
- Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, Guangzhou, China.
- National Key Clinical Department and Key Discipline of Neurology, Guangzhou, China.
| | - Haishan Qiu
- Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, 518000, Guangdong, China.
| | - Jianping Chu
- Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58th, The Second Zhongshan Road, Guangzhou, 518000, Guangdong, China.
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Stezin A, Bhardwaj S, Khokhar S, Hegde S, Jain S, Bharath RD, Saini J, Pal PK. In vivo microstructural white matter changes in early spinocerebellar ataxia 2. Acta Neurol Scand 2021; 143:326-332. [PMID: 33029780 DOI: 10.1111/ane.13359] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/24/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVE White matter (WM) integrity of Spinocerebellar ataxia 2 (SCA2) is poorly understood, more so in the early stages of SCA2. In this study, we evaluated the microstructural integrity of the WM tracts with an emphasis on the nature of in vivo pathological involvement in early SCA2. MATERIALS AND METHODS We evaluated the MRI images of 26 genetically proven SCA2 patients with disease duration <5 years and 24 age- and gender-matched healthy controls using tract-based spatial statistics (TBSS) to identify the WM tract changes and their clinico-genetic correlates (age at onset, duration of disease, ataxia severity and CAG repeat length) using standard methodology. RESULTS The mean age at onset and duration of disease were 28.7 ± 8.51 years and 3.5 ± 0.69 months, respectively. The mean CAG repeat length was 42.5 ± 4.6, and the ataxia severity score was 16.1 ± 4.9. Altered DTI scalars signifying degeneration was present in the bilateral anterior thalamic radiation (ATR), corticospinal tract (CST), inferior fronto-occipital fasciculus (IFOF), superior and inferior longitudinal fasciculus (SLF and ILF), uncinate fasciculus (UF), cingulum, corpus callosum (CC), forceps major and forceps minor (corrected p < .05). DTI scalars representing demyelination was seen in the superior cerebellar peduncle (SCP) and cerebellar WM. There was a significant correlation of SARA score with axial diffusivity of the bilateral cingulum, ATR, CST, forceps minor, IFOF, ILF, SLF and SCP on the right side (corrected p < .05). CONCLUSION Extensive WM involvement is present in early SCA2. The DTI scalars indicate degeneration and demyelination and may have clinical implications.
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Affiliation(s)
- Albert Stezin
- Department of Clinical Neurosciences, Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sujas Bhardwaj
- Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sunil Khokhar
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Shantala Hegde
- Department of Clinical Neuropsychology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sanjeev Jain
- Department of Psychiatry National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Jitender Saini
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Pramod Kumar Pal
- Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
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Nigri A, Sarro L, Mongelli A, Pinardi C, Porcu L, Castaldo A, Ferraro S, Grisoli M, Bruzzone MG, Gellera C, Taroni F, Mariotti C, Nanetti L. Progression of Cerebellar Atrophy in Spinocerebellar Ataxia Type 2 Gene Carriers: A Longitudinal MRI Study in Preclinical and Early Disease Stages. Front Neurol 2020; 11:616419. [PMID: 33384659 PMCID: PMC7770103 DOI: 10.3389/fneur.2020.616419] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
Spinocerebellar ataxias type 2 (SCA2) is an autosomal dominant inherited disease caused by expanded trinucleotide repeats (≥32 CAG) within the coding region of ATXN2 gene. Age of disease onset primarily depends on the length of the expanded region. The majority of subjects carrying the mutation remain free of clinical signs for few decades (“pre-symptomatic” stage), but in proximity of disease onset subtle neurophysiological, cognitive, and structural brain imaging changes may occur. Aims of the present study are to determine the time-window in which early clinical and neurodegenerative MRI changes may be identified, and to evaluate the rate of the disease progression in both preclinical and early disease phases. We performed a 1-year longitudinal study in 42 subjects: 14 SCA2 patients (mean age 39 years, disease duration 7 years, SARA score 9 points), 13 presymptomatic SCA2 subjects (preSCA2, mean age 39 years, expected time to disease onset 16 years), and 15 gene-negative healthy controls (mean age 33 years). All participants underwent genetic test, neurological examination, cognitive tests, and brain MRI. Evaluations were repeated at 1-year interval. Baseline MRI evaluations in SCA2 patients showed significant atrophy in cerebellum, brainstem, basal ganglia and cortex compared to controls, while preSCA2 subjects had isolated volume loss in the pons, and cortical thinning in specific frontal and parietal areas, namely rostral-middle-frontal and precuneus. One-year longitudinal follow-up demonstrated, in SCA2 patients, volume reduction in cerebellum, pons, superior cerebellar peduncles, and midbrain, and only in the cerebellum in preSCA2 subjects. No progression in clinical or cognitive measures was observed in preSCA2 subjects. The rate of volume loss in the cerebellum and subcortical regions greatly differed between patients and preSCA2. In conclusion, our pilot study demonstrated that MRI measures are highly sensitive to identify longitudinal structural changes in SCA2 patients, and in preSCA2 up to a decade before expected disease onset. These findings may contribute in the understanding of early neurodegenerative processes and may be useful in future therapeutical trials.
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Affiliation(s)
- Anna Nigri
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Lidia Sarro
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy.,Ospedale Martini, Turin, Italy
| | - Alessia Mongelli
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Chiara Pinardi
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Luca Porcu
- Laboratory of Methodology for Clinical Research, Oncology Department, Istituto di Ricerche Farmacologiche Mario Negri Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | - Anna Castaldo
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Stefania Ferraro
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marina Grisoli
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Maria Grazia Bruzzone
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Cinzia Gellera
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Franco Taroni
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Caterina Mariotti
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Lorenzo Nanetti
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
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Mascalchi M, Vella A. Neuroimaging Biomarkers in SCA2 Gene Carriers. Int J Mol Sci 2020; 21:ijms21031020. [PMID: 32033120 PMCID: PMC7037189 DOI: 10.3390/ijms21031020] [Citation(s) in RCA: 8] [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: 12/21/2019] [Revised: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 12/12/2022] Open
Abstract
A variety of Magnetic Resonance (MR) and nuclear medicine (NM) techniques have been used in symptomatic and presymptomatic SCA2 gene carriers to explore, in vivo, the physiopathological biomarkers of the neurological dysfunctions characterizing the associated progressive disease that presents with a cerebellar syndrome, or less frequently, with a levodopa-responsive parkinsonian syndrome. Morphometry performed on T1-weighted images and diffusion MR imaging enable structural and microstructural evaluation of the brain in presymptomatic and symptomatic SCA2 gene carriers, in whom they show the typical pattern of olivopontocerebellar atrophy observed at neuropathological examination. Proton MR spectroscopy reveals, in the pons and cerebellum of SCA2 gene carriers, a more pronounced degree of abnormal neurochemical profile compared to other spinocerebellar ataxias with decreased NAA/Cr and Cho/Cr, increased mi/Cr ratios, and decreased NAA and increased mI concentrations. These neurochemical abnormalities are detectable also in presymtomatic gene carriers. Resting state functional MRI (rsfMRI) demonstrates decreased functional connectivity within the cerebellum and of the cerebellum with fronto-parietal cortices and basal ganglia in symptomatic SCA2 subjects. 18F-fluorodeoxyglucose Positron Emission Tomography (PET) shows a symmetric decrease of the glucose uptake in the cerebellar cortex, the dentate nucleus, the brainstem and the parahippocampal cortex. Single photon emission tomography and PET using several radiotracers have revealed almost symmetric nigrostriatal dopaminergic dysfunction irrespective of clinical signs of parkinsonism which are already present in presymtomatic gene carriers. Longitudinal small size studies have proven that morphometry and diffusion MR imaging can track neurodegeneration in SCA2, and hence serve as progression biomarkers. So far, such a capability has not been reported for proton MR spectroscopy, rsfMRI and NM techniques. A search for the best surrogate marker for future clinical trials represents the current challenge for the neuroimaging community.
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Affiliation(s)
- Mario Mascalchi
- Department of Clinical and Experimental Biomedical Sciences, University of Florence, 50121 Florence, Italy
- Correspondence: ; Tel.: +39-329-808-1701
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Tax CMW, Szczepankiewicz F, Nilsson M, Jones DK. The dot-compartment revealed? Diffusion MRI with ultra-strong gradients and spherical tensor encoding in the living human brain. Neuroimage 2020; 210:116534. [PMID: 31931157 PMCID: PMC7429990 DOI: 10.1016/j.neuroimage.2020.116534] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/12/2019] [Accepted: 01/09/2020] [Indexed: 11/29/2022] Open
Abstract
The so-called “dot-compartment” is conjectured in diffusion MRI to represent small spherical spaces, such as cell bodies, in which the diffusion is restricted in all directions. Previous investigations inferred its existence from data acquired with directional diffusion encoding which does not permit a straightforward separation of signals from ‘sticks’ (axons) and signals from ‘dots’. Here we combine isotropic diffusion encoding with ultra-strong diffusion gradients (240 mT/m) to achieve high diffusion-weightings with high signal to noise ratio, while suppressing signal arising from anisotropic water compartments with significant mobility along at least one axis (e.g., axons). A dot-compartment, defined to have apparent diffusion coefficient equal to zero and no exchange, would result in a non-decaying signal at very high b-values (b≳7000s/mm2). With this unique experimental setup, a residual yet slowly decaying signal above the noise floor for b-values as high as 15000s/mm2 was seen clearly in the cerebellar grey matter (GM), and in several white matter (WM) regions to some extent. Upper limits of the dot-signal-fraction were estimated to be 1.8% in cerebellar GM and 0.5% in WM. By relaxing the assumption of zero diffusivity, the signal at high b-values in cerebellar GM could be represented more accurately by an isotropic water pool with a low apparent diffusivity of 0.12 μm2/ms and a substantial signal fraction of 9.7%. The T2 of this component was estimated to be around 61ms. This remaining signal at high b-values has potential to serve as a novel and simple marker for isotropically-restricted water compartments in cerebellar GM. The “dot-compartment” is conjectured in diffusion MRI to represent e.g. cell bodies. We combine isotropic encoding with ultra-strong gradients to study the dot-compartment. A slowly decaying signal for high b-values was seen in cerebellar GM. An apparent diffusivity of 0.12 and signal fraction of 9.7% were estimated. The signal could serve as a novel and simple marker for spherical compartments.
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Affiliation(s)
- Chantal M W Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK.
| | - Filip Szczepankiewicz
- Radiology, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Medical Radiation Physics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Markus Nilsson
- Radiology, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK; Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
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8
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Mascalchi M, Vella A. Neuroimaging Applications in Chronic Ataxias. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 143:109-162. [PMID: 30473193 DOI: 10.1016/bs.irn.2018.09.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission tomography (PET) are the main instruments for neuroimaging investigation of patients with chronic ataxia. MRI has a predominant diagnostic role in the single patient, based on the visual detection of three patterns of atrophy, namely, spinal atrophy, cortical cerebellar atrophy and olivopontocerebellar atrophy, which correlate with the aetiologies of inherited or sporadic ataxia. In fact spinal atrophy is observed in Friedreich ataxia, cortical cerebellar atrophy in Ataxia Telangectasia, gluten ataxia and Sporadic Adult Onset Ataxia and olivopontocerebellar atrophy in Multiple System Atrophy cerebellar type. The 39 types of dominantly inherited spinocerebellar ataxias show either cortical cerebellar atrophy or olivopontocerebellar atrophy. T2 or T2* weighted MR images can contribute to the diagnosis by revealing abnormally increased or decreased signal with a characteristic distribution. These include symmetric T2 hyperintensity of the posterior and lateral columns of the cervical spinal cord in Friedreich ataxia, diffuse and symmetric hyperintensity of the cerebellar cortex in Infantile Neuro-Axonal Dystrophy, symmetric hyperintensity of the peridentate white matter in Cerebrotendineous Xanthomatosis, and symmetric hyperintensity of the middle cerebellar peduncles and peridentate white matter, cerebral white matter and corpus callosum in Fragile X Tremor Ataxia Syndrome. Abnormally decreased T2 or T2* signal can be observed with a multifocal distribution in Ataxia Telangectasia and with a symmetric distribution in the basal ganglia in Multiple System Atrophy. T2 signal hypointensity lining diffusely the outer surfaces of the brainstem, cerebellum and cerebrum enables diagnosis of superficial siderosis of the central nervous system. The diagnostic role of nuclear medicine techniques is smaller. SPECT and PET show decreased uptake of radiotracers investigating the nigrostriatal system in Multiple System Atrophy and in patients with Fragile X Tremor Ataxia Syndrome. Semiquantitative or quantitative MRI, SPECT and PET data describing structural, microstructural and functional changes of the cerebellum, brainstem, and spinal cord have been widely applied to investigate physiopathological changes in patients with chronic ataxias. Moreover they can track diseases progression with a greater sensitivity than clinical scales. So far, a few small-size and single center studies employed neuroimaging techniques as surrogate markers of treatment effects in chronic ataxias.
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Affiliation(s)
- Mario Mascalchi
- Meyer Children Hospital, Florence, Italy; Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy.
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9
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Reetz K, Rodríguez-Labrada R, Dogan I, Mirzazade S, Romanzetti S, Schulz JB, Cruz-Rivas EM, Alvarez-Cuesta JA, Aguilera Rodríguez R, Gonzalez Zaldivar Y, Auburger G, Velázquez-Pérez L. Brain atrophy measures in preclinical and manifest spinocerebellar ataxia type 2. Ann Clin Transl Neurol 2018; 5:128-137. [PMID: 29468174 PMCID: PMC5817824 DOI: 10.1002/acn3.504] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/06/2017] [Accepted: 10/21/2017] [Indexed: 01/11/2023] Open
Abstract
Objective Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominantly inherited neurodegenerative disease mainly affecting the cerebellum and brainstem. In this Cuban-German research collaboration, we aimed to characterize atrophy patterns and associations with clinical measures in preclinical and manifest SCA2. Methods In this study, 16 nonmanifest SCA2 mutation carriers, 26 manifest patients with SCA2, and 18 healthy control subjects underwent magnetic resonance imaging, as well as genetic and clinical characterization including assessment of ataxia (Scale for the Assessment and Rating of Ataxia) and saccade velocity in Cuba were enrolled. Semiautomated quantitative volumetry of the cerebellum and brainstem, subdivided into the medulla oblongata, the pontine brainstem, and mesencephalon was performed. Additionally, the anteroposterior diameter of the pontine brainstem was measured. Results Analysis of volumetric data revealed degeneration of the cerebellum and brainstem, in particular of pontine volumes and the anteroposterior diameter of the pons, in both manifest SCA2 patients and individuals at risk for SCA2 compared to controls. Comparing patients with nonataxic preclinical SCA2 mutation carriers, we found more pronounced reductions of the pontine brainstem and cerebellum in manifest SCA2. Volumetric data further showed associations with CAG repeat length and predicted age of onset in preclinical SCA2 individuals, and by trend with ataxia signs in patients. Although saccade velocity was associated with reduction in the pontine brainstem in preclinical and manifest SCA2, reduced ability to suppress interfering stimuli measured by the Stroop task was related to cerebellar volume loss in patients. Interpretation Preclinical SCA2 mutation carriers exhibit brain abnormalities, which could be targeted as surrogate parameters for disease progression and in future preventive trials.
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Affiliation(s)
- Kathrin Reetz
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Roberto Rodríguez-Labrada
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Imis Dogan
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Shahram Mirzazade
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Sandro Romanzetti
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Jörg B Schulz
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Edilia M Cruz-Rivas
- Department of Imaging Clinical-Surgical Hospital "Lucía Iñiguez". Avenue "Celia Sanchez 1 Holguín Cuba
| | - Jose A Alvarez-Cuesta
- Department of Imaging Clinical-Surgical Hospital "Lucía Iñiguez". Avenue "Celia Sanchez 1 Holguín Cuba
| | - Raul Aguilera Rodríguez
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Yanetza Gonzalez Zaldivar
- Department Molecular Genetics Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Georg Auburger
- Experimental Neurology Goethe University Medical School 60590 Frankfurt/Main Germany
| | - Luis Velázquez-Pérez
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
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10
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Gan SR, Wang J, Figueroa KP, Pulst SM, Tomishon D, Lee D, Perlman S, Wilmot G, Gomez CM, Schmahmann J, Paulson H, Shakkottai VG, Ying SH, Zesiewicz T, Bushara K, Geschwind MD, Xia G, Subramony SH, Ashizawa T, Kuo SH. Postural Tremor and Ataxia Progression in Spinocerebellar Ataxias. Tremor Other Hyperkinet Mov (N Y) 2017; 7:492. [PMID: 29057148 PMCID: PMC5647398 DOI: 10.7916/d8gm8krh] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/07/2017] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Postural tremor can sometimes occur in spinocerebellar ataxias (SCAs). However, the prevalence and clinical characteristics of postural tremor in SCAs are poorly understood, and whether SCA patients with postural tremor have different ataxia progression is not known. METHODS We studied postural tremor in 315 patients with SCA1, 2, 3, and 6 recruited from the Clinical Research Consortium for Spinocerebellar Ataxias (CRC-SCA), which consists of 12 participating centers in the United States, and we evaluated ataxia progression in these patients from January 2010 to August 2012. RESULTS Among 315 SCA patients, postural tremor was most common in SCA2 patients (SCA1, 5.8%; SCA2, 27.5%; SCA3, 12.4%; SCA6, 16.9%; p = 0.007). SCA3 patients with postural tremor had longer CAG repeat expansions than SCA3 patients without postural tremor (73.67 ± 3.12 vs. 70.42 ± 3.96, p = 0.003). Interestingly, SCA1 and SCA6 patients with postural tremor had a slower rate of ataxia progression (SCA1, β = -0.91, p < 0.001; SCA6, β = -1.28, p = 0.025), while SCA2 patients with postural tremor had a faster rate of ataxia progression (β = 1.54, p = 0.034). We also found that the presence of postural tremor in SCA2 patients could be influenced by repeat expansions of ATXN1 (β = -1.53, p = 0.037) and ATXN3 (β = 0.57, p = 0.018), whereas postural tremor in SCA3 was associated with repeat lengths in TBP (β = 0.63, p = 0.041) and PPP2R2B (β = -0.40, p = 0.032). DISCUSSION Postural tremor could be a clinical feature of SCAs, and the presence of postural tremor could be associated with different rates of ataxia progression. Genetic interactions between ataxia genes might influence the brain circuitry and thus affect the clinical presentation of postural tremor.
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Affiliation(s)
- Shi-Rui Gan
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
- Department of Neurology and Institute of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Jie Wang
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
- Department of Basic and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Darya Tomishon
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Danielle Lee
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Susan Perlman
- Department of Neurology, University of California, Los Angeles, CA, USA
| | - George Wilmot
- Department of Neurology, Emory University, Atlanta, GA, USA
| | | | - Jeremy Schmahmann
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Henry Paulson
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | | | - Sarah H. Ying
- Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
| | - Theresa Zesiewicz
- Department of Neurology, University of South Florida, Tampa, FL, USA
| | - Khalaf Bushara
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | | | - Guangbin Xia
- Department of Neurology, School of Medicine, University of New Mexico, Albuquerque, NM, USA
| | - S. H. Subramony
- Department of Neurology, School of Medicine, University of New Mexico, Albuquerque, NM, USA
| | | | - Sheng-Han Kuo
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
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11
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Sarro L, Nanetti L, Castaldo A, Mariotti C. Monitoring disease progression in spinocerebellar ataxias: implications for treatment and clinical research. Expert Rev Neurother 2017; 17:919-931. [PMID: 28805093 DOI: 10.1080/14737175.2017.1364628] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Spinocerebellar ataxias (SCAs) are autosomal dominant diseases characterized by progressive gait and limb incoordination, disequilibrium, dysarthria, and eye movement disturbances. Approximately 40 genetic subtypes of SCAs are known and classified according to the causative disease gene/locus. With the possibility of the specific genetic diagnosis in patients and at-risk family members, several clinical scales and functional tests have been validated and used in ataxic patients with the purposes of measuring the entity of disease progression in natural history studies and the possible slowing of neurological impairment in therapeutic trials. Areas covered: This paper reviews the most widely used clinical scales and quantitative tests that contributed in monitoring disease progression of the most common forms of SCAs. Expert commentary: The currently available and validated clinical scales and quantitative performance scores are adequate to measure disease severity, but may require a considerable number of subjects and a long period of treatment to allow the recognition of beneficial effect of interventional therapies. Advanced MRI techniques are a consistent biomarker and maybe useful to track disease progression from the preclinical to the manifest ataxic phase in association with appropriate clinical or paraclinical investigations.
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Affiliation(s)
- Lidia Sarro
- a Unit of Genetics of Neurodegenerative and Metabolic Diseases , Fondazione IRCCS Istituto Neurologico Carlo Besta , Milan , Italy
| | - Lorenzo Nanetti
- a Unit of Genetics of Neurodegenerative and Metabolic Diseases , Fondazione IRCCS Istituto Neurologico Carlo Besta , Milan , Italy
| | - Anna Castaldo
- a Unit of Genetics of Neurodegenerative and Metabolic Diseases , Fondazione IRCCS Istituto Neurologico Carlo Besta , Milan , Italy
| | - Caterina Mariotti
- a Unit of Genetics of Neurodegenerative and Metabolic Diseases , Fondazione IRCCS Istituto Neurologico Carlo Besta , Milan , Italy
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12
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Antenora A, Rinaldi C, Roca A, Pane C, Lieto M, Saccà F, Peluso S, De Michele G, Filla A. The Multiple Faces of Spinocerebellar Ataxia type 2. Ann Clin Transl Neurol 2017; 4:687-695. [PMID: 28904990 PMCID: PMC5590519 DOI: 10.1002/acn3.437] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/09/2017] [Accepted: 06/07/2017] [Indexed: 12/13/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is among the most common forms of autosomal dominant ataxias, accounting for 15% of the total families. Occurrence is higher in specific populations such as the Cuban and Southern Italian. The disease is caused by a CAG expansion in ATXN2 gene, leading to abnormal accumulation of the mutant protein, ataxin‐2, in intracellular inclusions. The clinical picture is mainly dominated by cerebellar ataxia, although a number of other neurological signs have been described, ranging from parkinsonism to motor neuron involvement, making the diagnosis frequently challenging for neurologists, particularly when information about the family history is not available. Although the functions of ataxin‐2 have not been completely elucidated, the protein is involved in mRNA processing and control of translation. Recently, it has also been shown that the size of the CAG repeat in normal alleles represents a risk factor for ALS, suggesting that ataxin‐2 plays a fundamental role in maintenance of neuronal homeostasis.
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Affiliation(s)
- Antonella Antenora
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Carlo Rinaldi
- Department of Physiology Anatomy and Genetics, University of Oxford Oxford United Kingdom
| | - Alessandro Roca
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Chiara Pane
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Maria Lieto
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy.,Department of Physiology Anatomy and Genetics, University of Oxford Oxford United Kingdom
| | - Francesco Saccà
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Silvio Peluso
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Giuseppe De Michele
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
| | - Alessandro Filla
- Department of Neurological Reproductive and Odontostomatological Sciences Federico II University Naples Italy
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13
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Cocozza S, Saccà F, Cervo A, Marsili A, Russo CV, Giorgio SMDA, De Michele G, Filla A, Brunetti A, Quarantelli M. Modifications of resting state networks in spinocerebellar ataxia type 2. Mov Disord 2015; 30:1382-90. [PMID: 26094751 DOI: 10.1002/mds.26284] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/13/2015] [Accepted: 05/11/2015] [Indexed: 12/29/2022] Open
Abstract
PURPOSE We aimed to investigate the integrity of the Resting State Networks in spinocerebellar ataxia type 2 (SCA2) and the correlations between the modification of these networks and clinical variables. METHODS Resting-state functional magnetic resonance imaging (RS-fMRI) data from 19 SCA2 patients and 29 healthy controls were analyzed using an independent component analysis and dual regression, controlling at voxel level for the effect of atrophy by co-varying for gray matter volume. Correlations between the resting state networks alterations and disease duration, age at onset, number of triplets, and clinical score were assessed by Spearman's coefficient, for each cluster which was significantly different in SCA2 patients compared with healthy controls. RESULTS In SCA2 patients, disruption of the cerebellar components of all major resting state networks was present, with supratentorial involvement only for the default mode network. When controlling at voxel level for gray matter volume, the reduction in functional connectivity in supratentorial regions of the default mode network, and in cerebellar regions within the default mode, executive and right fronto-parietal networks, was still significant. No correlations with clinical variables were found for any of the investigated resting state networks. CONCLUSIONS The SCA2 patients show significant alterations of the resting state networks, only partly explained by the atrophy. The default mode network is the only resting state network that shows also supratentorial changes, which appear unrelated to the cortical gray matter volume. Further studies are needed to assess the clinical significance of these changes.
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Affiliation(s)
- Sirio Cocozza
- Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy
| | - Francesco Saccà
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University "Federico II", Naples, Italy
| | - Amedeo Cervo
- Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy
| | - Angela Marsili
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University "Federico II", Naples, Italy
| | - Cinzia Valeria Russo
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University "Federico II", Naples, Italy
| | | | - Giuseppe De Michele
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University "Federico II", Naples, Italy
| | - Alessandro Filla
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University "Federico II", Naples, Italy
| | - Arturo Brunetti
- Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy
| | - Mario Quarantelli
- Biostructure and Bioimaging Institute, National Research Council, Naples, Italy
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14
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Mascalchi M, Toschi N, Giannelli M, Ginestroni A, Della Nave R, Nicolai E, Bianchi A, Tessa C, Salvatore E, Aiello M, Soricelli A, Diciotti S. Progression of microstructural damage in spinocerebellar ataxia type 2: a longitudinal DTI study. AJNR Am J Neuroradiol 2015; 36:1096-101. [PMID: 25882284 DOI: 10.3174/ajnr.a4343] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 11/21/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE The ability of DTI to track the progression of microstructural damage in patients with inherited ataxias has not been explored so far. We performed a longitudinal DTI study in patients with spinocerebellar ataxia type 2. MATERIALS AND METHODS Ten patients with spinocerebellar ataxia type 2 and 16 healthy age-matched controls were examined twice with DTI (mean time between scans, 3.6 years [patients] and 3.3 years [controls]) on the same 1.5T MR scanner. Using tract-based spatial statistics, we analyzed changes in DTI-derived indices: mean diffusivity, axial diffusivity, radial diffusivity, fractional anisotropy, and mode of anisotropy. RESULTS At baseline, the patients with spinocerebellar ataxia type 2, as compared with controls, showed numerous WM tracts with significantly increased mean diffusivity, axial diffusivity, and radial diffusivity and decreased fractional anisotropy and mode of anisotropy in the brain stem, cerebellar peduncles, cerebellum, cerebral hemisphere WM, corpus callosum, and thalami. Longitudinal analysis revealed changes in axial diffusivity and mode of anisotropy in patients with spinocerebellar ataxia type 2 that were significantly different than those in the controls. In patients with spinocerebellar ataxia type 2, axial diffusivity was increased in WM tracts of the right cerebral hemisphere and the corpus callosum, and the mode of anisotropy was extensively decreased in hemispheric cerebral WM, corpus callosum, internal capsules, cerebral peduncles, pons and left cerebellar peduncles, and WM of the left paramedian vermis. There was no correlation between the progression of changes in DTI-derived indices and clinical deterioration. CONCLUSIONS DTI can reveal the progression of microstructural damage of WM fibers in the brains of patients with spinocerebellar ataxia type 2, and mode of anisotropy seems particularly sensitive to such changes. These results support the potential of DTI-derived indices as biomarkers of disease progression.
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Affiliation(s)
- M Mascalchi
- From the Quantitative and Functional Neuroradiology Research Unit (M.M.), Meyer Children and Careggi Hospitals of Florence, Florence, Italy "Mario Serio" Department of Experimental and Clinical Biomedical Sciences (M.M., A.B.), University of Florence, Florence, Italy
| | - N Toschi
- Medical Physics Section (N.T.), Department of Biomedicine and Prevention, University of Rome "Tor Vergata," Rome, Italy Department of Radiology (N.T.), Athinoula A. Martinos Center for Biomedical Imaging, Boston, Massachusetts Harvard Medical School (N.T.), Boston, Massachusetts
| | - M Giannelli
- Unit of Medical Physics (M.G.), Pisa University Hospital "Azienda Ospedaliero-Universitaria Pisana," Pisa, Italy
| | - A Ginestroni
- Neuroradiology Unit (A.G.), Careggi General Hospital, Florence, Italy
| | | | - E Nicolai
- IRCSS SDN Foundation (E.N., M.A., A.S.), Naples, Italy
| | - A Bianchi
- From the Quantitative and Functional Neuroradiology Research Unit (M.M.), Meyer Children and Careggi Hospitals of Florence, Florence, Italy
| | - C Tessa
- Unit of Radiology (C.T.), Versilia Hospital, Lido di Camaiore, Italy
| | - E Salvatore
- Department of Neurological Sciences (E.S.), University of Naples Federico II, Naples, Italy
| | - M Aiello
- IRCSS SDN Foundation (E.N., M.A., A.S.), Naples, Italy
| | - A Soricelli
- IRCSS SDN Foundation (E.N., M.A., A.S.), Naples, Italy University of Naples Parthenope (A.S.), Naples, Italy
| | - S Diciotti
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi" (S.D.), University of Bologna, Cesena, Italy
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