Neuroanatomical features and its usefulness in classification of patients with PANDAS

ObjectiveAn obsessive-compulsive disorder (OCD) subtype has been associated with streptococcal infections and is called pediatric autoimmune neuropsychiatric disorders associated with streptococci (PANDAS). The neuroanatomical characterization of subjects with this disorder is crucial for the better understanding of its pathophysiology; also, evaluation of these features as classifiers between patients and controls is relevant to determine potential biomarkers and useful in clinical diagnosis. This was the first multivariate pattern analysis (MVPA) study on an early-onset OCD subtype.MethodsFourteen pediatric patients with PANDAS were paired with 14 healthy subjects and were scanned to obtain structural magnetic resonance images (MRI). We identified neuroanatomical differences between subjects with PANDAS and healthy controls using voxel-based morphometry, diffusion tensor imaging (DTI), and surface analysis. We investigated the usefulness of these neuroanatomical differences to classify patients with PANDAS using MVPA.ResultsThe pattern for the gray and white matter was significantly different between subjects with PANDAS and controls. Alterations emerged in the cortex, subcortex, and cerebellum. There were no significant group differences in DTI measures (fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity) or cortical features (thickness, sulci, volume, curvature, and gyrification). The overall accuracy of 75% was achieved using the gray matter features to classify patients with PANDAS and healthy controls.ConclusionThe results of this integrative study allow a better understanding of the neural substrates in this OCD subtype, suggesting that the anatomical gray matter characteristics could have an immune origin that might be helpful in patient classification.

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Increased fractional anisotropy in cerebellum in obsessive–compulsive disorder

Acta Neuropsychiatrica ◽

10.1017/neu.2015.57 ◽

2015 ◽

Vol 28 (3) ◽

pp. 141-148 ◽

Cited By ~ 7

Author(s):

Tue Hartmann ◽

Sanne Vandborg ◽

Raben Rosenberg ◽

Leif Sørensen ◽

Poul Videbech

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Fractional Anisotropy ◽

White Matter Hyperintensities ◽

Diffusion Tensor ◽

Healthy Controls ◽

Obsessive Compulsive ◽

Compulsive Disorder ◽

And Diffusion ◽

Fractional Anisotrophy

BackgroundPrevious morphology and diffusion-imaging studies have suggested that structural changes in white matter is an important part of the pathophysiology of obsessive–compulsive disorder (OCD). However, different methodological approaches and the heterogeneity of patient samples question the validity of the findings.Materials and methodsIn total, 30 patients were matched for age and sex with 30 healthy controls. All participants underwent T1-weighted magnetic resonance imaging, diffusion tensor imaging and T2 fluid-attenuated inversion recovery. Voxel-based morphometry and tract-based spatial statistics were used to compare white matter volumes and diffusion tensor imaging between groups. These data were analysed correcting for the effects of multiple comparisons, age, sex, severity and duration of illness as nuisance covariates. White matter hyperintensities were manually identified.ResultsIncrease in fractional anisotropy in cerebellum was the most prominent result. A decrease in fractional anisotrophy in patients comparable with previous studies was located in forceps minor. There were no differences in the white matter morphology or in the white matter hyperintensities between patients and healthy controls.ConclusionDecrease in fractional anisotrophy in forceps minor and increase in cerebellum were found, and they were not due to neither white matter hyperintensities nor morphology of the white matter. Cerebellar hyperconnectivity could be an important part of OCD pathophysiology.

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Diffusion Tensor Imaging Before and 3 Months After Concentrated Exposure Response Prevention in Obsessive-Compulsive Disorder

Frontiers in Psychiatry ◽

10.3389/fpsyt.2021.674020 ◽

2021 ◽

Vol 12 ◽

Author(s):

Vilde Brecke ◽

Anders Lillevik Thorsen ◽

Olga Therese Ousdal ◽

Chris Vriend ◽

Dag Alnæs ◽

...

Keyword(s):

Treatment Outcome ◽

Diffusion Tensor Imaging ◽

White Matter ◽

Obsessive Compulsive Disorder ◽

Diffusion Tensor ◽

Healthy Controls ◽

Obsessive Compulsive ◽

Illness Onset ◽

Compulsive Disorder ◽

White Matter Microstructure

Background: Subtle differences in white matter microstructure have been found in obsessive-compulsive disorder (OCD) compared to controls using diffusion tensor imaging (DTI), but it is unclear if and how this change after treatment. The primary aim of this pre-registered study was to investigate white matter integrity between OCD patients and controls and changes after concentrated exposure and response prevention (ERP).Methods: Fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) and mean diffusivity (MD) were estimated using FMRIB Software Library (FSL). The images were registered to a study-specific template using a longitudinal pipeline based on full tensor information in DTI-TK. Voxel-based analysis was performed using tract-based spatial statistics (TBSS). Using SPSS, we compared the integrity in three bilateral regions of interest (ROI), the sagittal stratum, posterior thalamic radiation and cingulum, in 32 OCD patients and 30 matched healthy controls at baseline. Patients received a four-day concentrated ERP format. We investigated longitudinal changes in 26 OCD patients and 22 healthy controls at 3months follow-up using repeated-measures ANOVA. Exploratory t-tests were conducted for AD and MD. Secondary hypothesis used linear regression to investigate if baseline FA predict treatment outcome 3 months later, and if patients with illness onset before 18 years of age would show lower FA in sagittal stratum. Finally, we performed sensitivity analysis on medication and comorbidity influences on FA.Results: Three months after treatment, 77% of the patients were in remission. Contrary to our hypotheses, we did not find any significant differences in FA, RD, AD or MD between the groups before treatment, nor significant group by time effects in any of the ROI. None of the baseline FA measures significantly predicted treatment outcome. Illness onset before 18 years of age did not significantly predict FA in the sagittal stratum. Adjusting for medication or comorbid anxiety or mood disorder did not influence the results.Conclusions: Although concentrated ERP in OCD lead to high remission, we did not find significant long-term changes by DTI. Future studies will benefit from using larger sample sizes and multi-shell diffusion-weighted imaging when investigating white matter microstructure in OCD and underlying neurobiological mechanisms of treatment.

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White Matter Changes in OCD Revealed by Diffusion Tensor Imaging

CNS Spectrums ◽

10.1017/s1092852912000260 ◽

2011 ◽

Vol 16 (5) ◽

pp. 101-109 ◽

Cited By ~ 24

Author(s):

Leonardo F. Fontenelle ◽

Ivanei E. Bramati ◽

Jorge Moll ◽

Mauro V. Mendlowicz ◽

Ricardo de Oliveira-Souza ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Healthy Volunteers ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Internal Capsule ◽

Brain Regions ◽

Obsessive Compulsive ◽

Posterior Limb ◽

Compulsive Disorder

AbstractIntroductionThe aim of this study was to investigate white matter (WM) abnormalities in obsessive-compulsive disorder (OCD) and its relationship to severity of obsessive-compulsive symptoms.MethodsConventional and diffusion tensor imaging were acquired in nine patients with OCD and nine gender- and age-matched healthy volunteers. Changes in fractional anisotropy (FA) and mean diffusivity (MD) were investigated using selected regions of interest (ROIs) analyses and whole brain tract-based spatial statistic analyses. A priori ROIs were placed bilaterally in internal capsule (IC), superior longitudinal fascicule (SLF), cingulate bundle (CB), and corpus calosum (CC).ResultsROIs analyses showed that, as compared to healthy volunteers, patients with OCD exhibited reduced FA values bilaterally in regions of the posterior limb of the IC and in the SLF and increased MD values bilaterally in the posterior limb of the IC, in the left CB, and in the splenium of CC. Voxelwise analysis showed that, as compared to controls, patients with OCD exhibited reduced FA and increased MD in regions of the cortical spinal tract (genu and posterior limb of internal capsule and corona radiata) and the SLF. Severity of OCD correlated with WM alterations in different brain regions, ie, the left (rho=0.70 [MD]) and right (rho=0.70 [MD]) anterior limb of the IC, the left (rho=0.97 [MD]) and right SLF (rho=0.81 [MD]), and the genu of CC (rho=0.66 [MD]; rho=-0.69 [FA]).ConclusionOur findings support the involvement of different WM tracts in OCD and suggest that greater impairment in WM integrity is associated with increased severity of OCD symptoms.

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Relationship between symptom dimensions and white matter alterations in obsessive-compulsive disorder

Acta Neuropsychiatrica ◽

10.1017/neu.2016.45 ◽

2016 ◽

Vol 29 (3) ◽

pp. 153-163 ◽

Cited By ~ 11

Author(s):

Michiyo Yagi ◽

Yoshiyuki Hirano ◽

Michiko Nakazato ◽

Kiyotaka Nemoto ◽

Kazuhiro Ishikawa ◽

...

Keyword(s):

White Matter ◽

Obsessive Compulsive Disorder ◽

Diffusion Tensor ◽

Inferior Frontal Gyrus ◽

Mean Diffusivity ◽

Brain Regions ◽

Middle Temporal Gyrus ◽

Obsessive Compulsive ◽

Symptom Dimensions ◽

Compulsive Disorder

ObjectiveTo investigate the relationship between the severities of symptom dimensions in obsessive-compulsive disorder (OCD) and white matter alterations.MethodsWe applied tract-based spatial statistics for diffusion tensor imaging (DTI) acquired by 3T magnetic resonance imaging. First, we compared fractional anisotropy (FA) between 20 OCD patients and 30 healthy controls (HC). Then, applying whole brain analysis, we searched the brain regions showing correlations between the severities of symptom dimensions assessed by Obsessive-Compulsive Inventory-Revised and FA in all participants. Finally, we calculated the correlations between the six symptom dimensions and multiple DTI measures [FA, axial diffusivity (AD), radial diffusivity (RD), mean diffusivity (MD)] in a region-of-interest (ROI) analysis and explored the differences between OCD patients and HC.ResultsThere were no between-group differences in FA or brain region correlations between the severities of symptom dimensions and FA in any of the participants. ROI analysis revealed negative correlations between checking severity and left inferior frontal gyrus white matter and left middle temporal gyrus white matter and a positive correlation between ordering severity and right precuneus in FA in OCD compared with HC. We also found negative correlations between ordering severity and right precuneus in RD, between obsessing severities and right supramarginal gyrus in AD and MD, and between hoarding severity and right insular gyrus in AD.ConclusionOur study supported the hypothesis that the severities of respective symptom dimensions are associated with different patterns of white matter alterations.

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Analysis of alterations in white matter integrity of adult patients with comitant exotropia

Journal of International Medical Research ◽

10.1177/0300060518763704 ◽

2018 ◽

Vol 46 (5) ◽

pp. 1963-1972

Author(s):

Dan Li ◽

Shenghong Li ◽

Xianjun Zeng

Keyword(s):

White Matter ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Magnetic Resonance Images ◽

Healthy Controls ◽

Imaging Data ◽

Inferior Longitudinal Fasciculus ◽

Structural Abnormalities ◽

The Right ◽

Diffusion Tensor Imaging Data

Objective This study was performed to investigate structural abnormalities of the white matter in patients with comitant exotropia using the tract-based spatial statistics (TBSS) method. Methods Diffusion tensor imaging data from magnetic resonance images of the brain were collected from 20 patients with comitant exotropia and 20 age- and sex-matched healthy controls. The FMRIB Software Library was used to compute the diffusion measures, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). These measures were obtained using voxel-wise statistics with threshold-free cluster enhancement. Results The FA values in the right inferior fronto-occipital fasciculus (IFO) and right inferior longitudinal fasciculus were significantly higher and the RD values in the bilateral IFO, forceps minor, left anterior corona radiata, and left anterior thalamic radiation were significantly lower in the comitant exotropia group than in the healthy controls. No significant differences in the MD or AD values were found between the two groups. Conclusions Alterations in FA and RD values may indicate the underlying neuropathologic mechanism of comitant exotropia. The TBSS method can be a useful tool to investigate neuronal tract participation in patients with this disease.

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