Frontiers in neuroimaging最新文献

{"title":"Pseudo-Label Assisted nnU-Net enables automatic segmentation of 7T MRI from a single acquisition","authors":"Corinne Donnay, H. Dieckhaus, C. Tsagkas, María Inés Gaitán, E. Beck, Andrew Mullins, Daniel S. Reich, G. Nair","doi":"10.3389/fnimg.2023.1252261","DOIUrl":"https://doi.org/10.3389/fnimg.2023.1252261","url":null,"abstract":"Automatic whole brain and lesion segmentation at 7T presents challenges, primarily from bias fields, susceptibility artifacts including distortions, and registration errors. Here, we sought to use deep learning algorithms (D/L) to do both skull stripping and whole brain segmentation on multiple imaging contrasts generated in a single Magnetization Prepared 2 Rapid Acquisition Gradient Echoes (MP2RAGE) acquisition on participants clinically diagnosed with multiple sclerosis (MS), bypassing registration errors.Brain scans Segmentation from 3T and 7T scanners were analyzed with software packages such as FreeSurfer, Classification using Derivative-based Features (C-DEF), nnU-net, and a novel 3T-to-7T transfer learning method, Pseudo-Label Assisted nnU-Net (PLAn). 3T and 7T MRIs acquired within 9 months from 25 study participants with MS (Cohort 1) were used for training and optimizing. Eight MS patients (Cohort 2) scanned only at 7T, but with expert annotated lesion segmentation, was used to further validate the algorithm on a completely unseen dataset. Segmentation results were rated visually by experts in a blinded fashion and quantitatively using Dice Similarity Coefficient (DSC).Of the methods explored here, nnU-Net and PLAn produced the best tissue segmentation at 7T for all tissue classes. In both quantitative and qualitative analysis, PLAn significantly outperformed nnU-Net (and other methods) in lesion detection in both cohorts. PLAn's lesion DSC improved by 16% compared to nnU-Net.Limited availability of labeled data makes transfer learning an attractive option, and pre-training a nnUNet model using readily obtained 3T pseudo-labels was shown to boost lesion detection capabilities at 7T.","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":" 41","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138613506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regression models for partially localized fMRI connectivity analyses","authors":"Bonnie B. Smith, Yi Zhao, Martin A. Lindquist, Brian Caffo","doi":"10.3389/fnimg.2023.1178359","DOIUrl":"https://doi.org/10.3389/fnimg.2023.1178359","url":null,"abstract":"Background Brain functional connectivity analysis of resting-state functional magnetic resonance imaging (fMRI) data is typically performed in a standardized template space assuming consistency of connections across subjects. Analysis methods can come in the form of one-edge-at-a-time analyses or dimension reduction/decomposition methods. Common to these approaches is an assumption that brain regions are functionally aligned across subjects; however, it is known that this functional alignment assumption is often violated. Methods In this paper, we use subject-level regression models to explain intra-subject variability in connectivity. Covariates can include factors such as geographic distance between two pairs of brain regions, whether the two regions are symmetrically opposite (homotopic), and whether the two regions are members of the same functional network. Additionally, a covariate for each brain region can be included, to account for the possibility that some regions have consistently higher or lower connectivity. This style of analysis allows us to characterize the fraction of variation explained by each type of covariate. Additionally, comparisons across subjects can then be made using the fitted connectivity regression models, offering a more parsimonious alternative to edge-at-a-time approaches. Results We apply our approach to Human Connectome Project data on 268 regions of interest (ROIs), grouped into eight functional networks. We find that a high proportion of variation is explained by region covariates and network membership covariates, while geographic distance and homotopy have high relative importance after adjusting for the number of predictors. We also find that the degree of data repeatability using our connectivity regression model—which uses only partial location information about pairs of ROI's—is comparably as high as the repeatability obtained using full location information. Discussion While our analysis uses data that have been transformed into a common template-space, we also envision the method being useful in multi-atlas registration settings, where subject data remains in its own geometry and templates are warped instead. These results suggest the tantalizing possibility that fMRI connectivity analysis can be performed in subject-space, using less aggressive registration, such as simple affine transformations, multi-atlas subject-space registration, or perhaps even no registration whatsoever.","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"28 14","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136282590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Profiles of resting state functional connectivity in temporal lobe epilepsy associated with post-laser interstitial thermal therapy seizure outcomes and semiologies","authors":"Mashaal Syed, Jingya Miao, Anish Sathe, Kichang Kang, Arichena Manmatharayan, Michael Kogan, Caio M. Matias, Ashwini Sharan, Mahdi Alizadeh","doi":"10.3389/fnimg.2023.1201682","DOIUrl":"https://doi.org/10.3389/fnimg.2023.1201682","url":null,"abstract":"Introduction It is now understood that in focal epilepsy, impacted neural regions are not limited to the epileptogenic zone. As such, further investigation into the underlying functional connectivity (FC) patterns in those enduring Temporal Lobe Epilepsy (TLE) with Mesial Temporal Sclerosis (MTS) is imperative to understanding the intricacies of the disease. Methods The rsfMRIs of 17 healthy participants, 10 left-sided TLE-MTS patients with a pre-operative history of focal impaired awareness seizures (FIA), and 13 left-sided TLE-MTS patients with a pre-operative history of focal aware seizures (FA) were compared to determine the existence of distinct FC patterns with respect to seizure types. Similarly, the rsfMRIs of the above-mentioned healthy participants, 16 left-sided TLE-MTS individuals who were seizure-free (SF) 12 months postoperatively, and 16 left-sided TLE-MTS persons without seizure freedom (nSF) were interrogated. The ROI-to-ROI connectivity analysis included a total of 175 regions of interest (ROIs) and accounted for both age and duration of epileptic activity. Significant correlations were determined via two-sample t- tests and Bonferroni correction (α = 0.05). Results Comparisons of FA and FIA groups depicted significant correlations between the contralateral anterior cingulate gyrus, subgenual region, and the contralateral cerebellum, lobule III ( p -value = 2.26e-4, mean z-score = −0.05 ± 0.28, T = −4.23). Comparisons of SF with nSF depicted two significantly paired-ROIs; the contralateral amygdala and the contralateral precuneus ( p- value = 2.9e-5, mean z-score = −0.12 ± 0.19, T = 4.98), as well as the contralateral locus coeruleus and the ipsilateral intralaminar nucleus ( p -value= 1.37e-4, mean z-score = 0.06 ± 0.17, T = −4.41). Significance FC analysis proves to be a lucrative modality for exploring unique signatures with respect to seizure types and postoperative outcomes. By furthering our understanding of the differences between epileptic phenotypes, we can achieve improvement in future treatment modalities not limited to targeting advancements.","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":" 43","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135292484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diffusion in the corpus callosum predicts persistence of clinical symptoms after mild traumatic brain injury, a multi-scanner study","authors":"Alexander Asturias, Thomas Knoblauch, Alan Rodriguez, Cheryl Vanier, Caroline Le Tohic, Brandon Barrett, Michael Eisenberg, Rachelle Gibbert, Lennon Zimmerman, Shaunaq Parikh, Anh Nguyen, Sherwin Azad, Leo Germin, Enrico Fazzini, Travis Snyder","doi":"10.3389/fnimg.2023.1153115","DOIUrl":"https://doi.org/10.3389/fnimg.2023.1153115","url":null,"abstract":"Background Mild traumatic brain injuries (mTBIs) comprise 80% of all TBI, but conventional MRI techniques are often insensitive to the subtle changes and injuries produced in a concussion. Diffusion tensor imaging (DTI) is one of the most sensitive MRI techniques for mTBI studies with outcome and symptom associations described. The corpus callosum (CC) is one of the most studied fiber tracts in TBI and mTBI, but the comprehensive post-mTBI symptom relationship has not fully been explored. Methods This is a retrospective observational study of how quantitative DTI data of the CC and its sub-regions may relate to clinical presentation of symptoms and timing of resolution of symptoms in patients diagnosed with uncomplicated mTBI. DTI and clinical data were obtained retrospectively from 446 (mean age 42 years, range 13–82) civilian patients. From patient medical charts, presentation of the following common post-concussive symptoms was noted: headache, balance issues, cognitive deficits, fatigue, anxiety, depression, and emotional lability. Also recorded was the time between injury and a visit to the physician when improvement or resolution of a particular symptom was reported. FA values from the total CC and 3 subregions of the CC (genu or anterior, mid body, and splenium or posterior) were obtained from hand tracing on the Olea Sphere v3.0 SP12 free-standing workstation. DTI data was obtained from 8 different 3T MRI scanners and harmonized via ComBat harmonization. The statistical models used to explore the association between regional Fractional Anisotropy (FA) values and symptom presentation and time to symptom resolution were logistic regression and interval-censored semi-parametric Cox proportional hazard models, respectively. Subgroups related to age and timing of first scan were also analyzed. Results Patients with the highest FA in the total CC ( p = 0.01), anterior CC ( p < 0.01), and mid-body CC ( p = 0.03), but not the posterior CC ( p = 0.91) recovered faster from post-concussive cognitive deficits. Patients with the highest FA in the posterior CC recovered faster from depression ( p = 0.04) and emotional lability ( p = 0.01). There was no evidence that FA in the CC or any of its sub-regions was associated with symptom presentation or with time to resolution of headache, balance issues, fatigue, or anxiety. Patients with mTBI under 40 had higher FA in the CC and the anterior and mid-body subregions (but not the posterior subregion: p = 1.00) compared to patients 40 or over ( p ≤ 0.01). There was no evidence for differences in symptom presentation based on loss of consciousness (LOC) or sex ( p ≥ 0.18). Conclusion This study suggests that FA of the CC has diagnostic and prognostic value for clinical assessment of mTBI in a large diverse civilian population, particularly in patients with cognitive symptoms.","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automatic planning of MR-guided transcranial focused ultrasound treatment for essential tremor.","authors":"Jan Klein, Annika Gerken, Niklas Agethen, Sven Rothlübbers, Neeraj Upadhyay, Veronika Purrer, Carsten Schmeel, Valeri Borger, Maya Kovalevsky, Itay Rachmilevitch, Yeruham Shapira, Ullrich Wüllner, Jürgen Jenne","doi":"10.3389/fnimg.2023.1272061","DOIUrl":"10.3389/fnimg.2023.1272061","url":null,"abstract":"<p><strong>Introduction: </strong>Transcranial focused ultrasound therapy (tcFUS) offers precise thermal ablation for treating Parkinson's disease and essential tremor. However, the manual fine-tuning of fiber tracking and segmentation required for accurate treatment planning is time-consuming and demands expert knowledge of complex neuroimaging tools. This raises the question of whether a fully automated pipeline is feasible or if manual intervention remains necessary.</p><p><strong>Methods: </strong>We investigate the dependence on fiber tractography algorithms, segmentation approaches, and degrees of automation, specifically for essential tremor therapy planning. For that purpose, we compare an automatic pipeline with a manual approach that requires the manual definition of the target point and is based on FMRIB software library (FSL) and other open-source tools.</p><p><strong>Results: </strong>Our findings demonstrate the high feasibility of automatic fiber tracking and the automated determination of standard treatment coordinates. Employing an automatic fiber tracking approach and deep learning (DL)-supported standard coordinate calculation, we achieve anatomically meaningful results comparable to a manually performed FSL-based pipeline. Individual cases may still exhibit variations, often stemming from differences in region of interest (ROI) segmentation. Notably, the DL-based approach outperforms registration-based methods in producing accurate segmentations. Precise ROI segmentation proves crucial, surpassing the importance of fine-tuning parameters or selecting algorithms. Correct thalamus and red nucleus segmentation play vital roles in ensuring accurate pathway computation.</p><p><strong>Conclusion: </strong>This study highlights the potential for automation in fiber tracking algorithms for tcFUS therapy, but acknowledges the ongoing need for expert verification and integration of anatomical expertise in treatment planning.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"2 ","pages":"1272061"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10637361/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89720937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Autonomous magnetic resonance imaging.","authors":"Sairam Geethanath, Rita G Nunes, Jon-Fredrik Nielsen","doi":"10.3389/fnimg.2023.1277580","DOIUrl":"10.3389/fnimg.2023.1277580","url":null,"abstract":"","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"2 ","pages":"1277580"},"PeriodicalIF":0.0,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10497867/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10272913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Psychopathic traits and altered resting-state functional connectivity in incarcerated adolescent girls.","authors":"Corey H Allen, J Michael Maurer, Aparna R Gullapalli, Bethany G Edwards, Eyal Aharoni, Carla L Harenski, Nathaniel E Anderson, Keith A Harenski, Vince D Calhoun, Kent A Kiehl","doi":"10.3389/fnimg.2023.1216494","DOIUrl":"10.3389/fnimg.2023.1216494","url":null,"abstract":"<p><p>Previous work in incarcerated boys and adult men and women suggest that individuals scoring high on psychopathic traits show altered resting-state limbic/paralimbic, and default mode functional network properties. However, it is unclear whether similar results extend to high-risk adolescent girls with elevated psychopathic traits. This study examined whether psychopathic traits [assessed via the Hare Psychopathy Checklist: Youth Version (PCL:YV)] were associated with altered inter-network connectivity, intra-network connectivity (i.e., functional coherence within a network), and amplitude of low-frequency fluctuations (ALFFs) across resting-state networks among high-risk incarcerated adolescent girls (<i>n</i> = 40). Resting-state networks were identified by applying group independent component analysis (ICA) to resting-state fMRI scans, and <i>a priori</i> regions of interest included limbic, paralimbic, and default mode network components. We tested the association of psychopathic traits (PCL:YV Factor 1 measuring affective/interpersonal traits and PCL:YV Factor 2 assessing antisocial/lifestyle traits) to these three resting-state measures. PCL:YV Factor 1 scores were associated with increased low-frequency and decreased high-frequency fluctuations in components corresponding to the default mode network, as well as increased intra-network FNC in components corresponding to cognitive control networks. PCL:YV Factor 2 scores were associated with increased low-frequency fluctuations in sensorimotor networks and decreased high-frequency fluctuations in default mode, sensorimotor, and visual networks. Consistent with previous analyses in incarcerated adult women, our results suggest that psychopathic traits among incarcerated adolescent girls are associated with altered intra-network ALFFs-primarily that of increased low-frequency and decreased high-frequency fluctuations-and connectivity across multiple networks including paralimbic regions. These results suggest stable neurobiological correlates of psychopathic traits among women across development.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"2 ","pages":"1216494"},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10406221/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9965709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Family history of substance use disorder and parental impulsivity are differentially associated with neural responses during risky decision-making.","authors":"Joseph Aloi,&nbsp;Elizabeth Kwon,&nbsp;Tom A Hummer,&nbsp;Kathleen I Crum,&nbsp;Nikhil Shah,&nbsp;Lauren Pratt,&nbsp;Matthew C Aalsma,&nbsp;Peter Finn,&nbsp;John Nurnberger,&nbsp;Leslie A Hulvershorn","doi":"10.3389/fnimg.2023.1110494","DOIUrl":"10.3389/fnimg.2023.1110494","url":null,"abstract":"<p><strong>Background: </strong>Risky decision-making is associated with the development of substance use behaviors during adolescence. Although prior work has investigated risky decision-making in adolescents at familial high risk for developing substance use disorders (SUDs), little research has controlled for the presence of co-morbid externalizing disorders (EDs). Additionally, few studies have investigated the role of parental impulsivity in offspring neurobiology associated with risky decision-making.</p><p><strong>Methods: </strong>One-hundred twenty-five children (28 healthy controls, 47 psychiatric controls with EDs <i>without</i> a familial history of SUD, and 50 high-risk children <i>with</i> co-morbid EDs with a familial history of SUD) participated in the Balloon Analog Risk Task while undergoing functional magnetic resonance imaging. Impulsivity for parents and children was measured using the UPPS-P Impulsive Behavior Scale.</p><p><strong>Results: </strong>We found that individuals in the psychiatric control group showed greater activation, as chances of balloon explosion increased, while making choices, relative to the healthy control and high-risk groups in the rostral anterior cingulate cortex (rACC) and lateral orbitofrontal cortex (lOFC). We also found a positive association between greater activation and parental impulsivity in these regions. However, within rACC, this relationship was moderated by group, such that there was a positive relationship between activation and parental impulsivity in the HC group, but an inverse relationship in the HR group.</p><p><strong>Conclusions: </strong>These findings suggest that there are key differences in the neurobiology underlying risky decision-making in individuals with EDs with and without a familial history of SUD. The current findings build on existing models of neurobiological factors influencing addiction risk by integrating parental factors. This work paves the way for more precise risk models in which to test preventive interventions.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"2 ","pages":"1110494"},"PeriodicalIF":0.0,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10406275/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9965711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Survey of neuroimaging in neurological surgery, current state, and emerging research","authors":"Saramati Narasimhan, Hernán F. J. González","doi":"10.3389/fnimg.2023.1022680","DOIUrl":"https://doi.org/10.3389/fnimg.2023.1022680","url":null,"abstract":"Neuroimaging plays a crucial role in enabling a surgeon's proficiency and achieving optimal outcomes across various subspecialties of neurosurgery. Since Wilhelm Roentgen's groundbreaking discovery of the radiograph in 1895, imaging capabilities have advanced astronomically, significantly benefiting the field of neurosurgery. In this review, we aim to provide a concise overview of neuroimaging in four specific subspecialties: neuro-oncology, cerebrovascular, spine, and functional neurosurgery. Although the diseases and procedures mentioned are not exhaustive, they are illustrative examples of how neuroimaging has contributed to advancements in neurosurgery. Our intention is to emphasize the critical role of neuroimaging in pre-operative, intra-operative, and post-operative settings, while also highlighting its potential to drive research to further enhance existing neurosurgical technologies and ultimately better patient outcomes.","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41445535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Translocator protein PET imaging in temporal lobe epilepsy: A reliable test-retest study using asymmetry index.","authors":"Mohammad Mahmud, Charles Wade, Sarah Jawad, Zaeem Hadi, Christian Otoul, Rafal M Kaminski, Pierandrea Muglia, Irena Kadiu, Eugenii Rabiner, Paul Maguire, David R Owen, Michael R Johnson","doi":"10.3389/fnimg.2023.1142463","DOIUrl":"10.3389/fnimg.2023.1142463","url":null,"abstract":"<p><strong>Objective: </strong>Translocator protein (TSPO) targeting positron emission tomography (PET) imaging radioligands have potential utility in epilepsy to assess the efficacy of novel therapeutics for targeting neuroinflammation. However, previous studies in healthy volunteers have indicated limited test-retest reliability of TSPO ligands. Here, we examine test-retest measures using TSPO PET imaging in subjects with epilepsy and healthy controls, to explore whether this biomarker can be used as an endpoint in clinical trials for epilepsy.</p><p><strong>Methods: </strong>Five subjects with epilepsy and confirmed mesial temporal lobe sclerosis (mean age 36 years, 3 men) were scanned twice-on average 8 weeks apart-using a second generation TSPO targeting radioligand, [¹¹C]PBR28. We evaluated the test-retest reliability of the volume of distribution and derived hemispheric asymmetry index of [¹¹C]PBR28 binding in these subjects and compared the results with 8 (mean age 45, 6 men) previously studied healthy volunteers.</p><p><strong>Results: </strong>The mean (± SD) of the volume of distribution (<i>V</i>_T), of all subjects, in patients living with epilepsy for both test and retest scans on all regions of interest (ROI) is 4.49 ± 1.54 vs. 5.89 ± 1.23 in healthy volunteers. The bias between test and retest in an asymmetry index as a percentage was small (-1.5%), and reliability is demonstrated here with Bland-Altman Plots (test mean 1.062, retest mean 2.56). In subjects with epilepsy, <i>V</i>_T of [¹¹C]PBR28 is higher in the (ipsilateral) hippocampal region where sclerosis is present than in the contralateral region.</p><p><strong>Conclusion: </strong>When using TSPO PET in patients with epilepsy with hippocampal sclerosis (HS), an inter-hemispheric asymmetry index in the hippocampus is a measure with good test-retest reliability. We provide estimates of test-retest variability that may be useful for estimating power where group change in <i>V</i>_T represents the clinical outcome.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"2 ","pages":"1142463"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10406252/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9965710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}