Structural brain MRI abnormalities in pediatric patients with migraine

Morphometric MRI studies in adult patients with migraine have consistently demonstrated atrophy of several gray matter (GM) regions involved in pain processing. We explored the regional distribution of GM and white matter (WM) abnormalities in pediatric patients with episodic migraine and their correlations with disease clinical manifestations. Using a 3.0 T scanner, brain T2-weighted and 3D T1-weighted scans were acquired from 12 pediatric migraine patients and 15 age-matched healthy controls. GM and WM volumetric abnormalities were estimated using voxel-based morphometry (p < 0.05, family-wise error corrected). Compared to controls, pediatric migraine patients experienced a significant GM atrophy of several regions of the frontal and temporal lobes which are part of the pain-processing network. They also had an increased volume of the right putamen. The left fusiform gyrus had an increased volume in patients with aura compared to patients without aura and controls, whereas it was significantly atrophied in patients without aura when compared to the other two groups. No abnormalities of WM volume were detected. In migraine patients, regional GM atrophy was not correlated with disease duration and attack frequency, whereas a negative correlation was found between increased volume of the putamen and disease duration (r = ?0.95, p < 0.05). These results show that GM morphometric abnormalities do occur in pediatric patients with migraine. The presence of such abnormalities early in the disease course, and the absence of correlation with patient clinical characteristics suggest that they may represent a phenotypic biomarker of this condition.     

Multimodal fusion analysis of structural connectivity and gray matter morphology in migraine

No specific migraine biomarkers have been found in single‐modality MRI studies. We aimed at establishing biomarkers for episodic and chronic migraine using diverse MRI modalities. We employed canonical correlation analysis and joint independent component analysis to find structural connectivity abnormalities that are related to gray matter morphometric alterations. The number of streamlines (trajectories of estimated fiber‐tracts from tractography) was employed as structural connectivity measure, while cortical curvature, thickness, surface area, and volume were used as gray matter parameters. These parameters were compared between 56 chronic and 54 episodic migraine patients, and 50 healthy controls. Cortical curvature alterations were associated with abnormalities in the streamline count in episodic migraine patients compared to controls, with higher curvature values in the frontal and temporal poles being related to a higher streamline count. Lower streamline count was found in migraine compared to controls in connections between cortical regions within each of the four lobes. Higher streamline count was found in migraine in connections between subcortical regions, the insula, and the cingulate and orbitofrontal cortex, and between the insula and the temporal region. The connections between the caudate nucleus and the orbitofrontal cortex presented worse connectivity in chronic compared to episodic migraine. The hippocampus was involved in connections with higher and lower number of streamlines in chronic migraine. Strengthening of structural networks involving pain processing and subcortical regions coexists in migraine with weakening of cortical networks within each lobe. The multimodal analysis offers a new insight about the association between brain structure and connectivity.     

Altered structure and functional connection in patients with classical trigeminal neuralgia

Classical trigeminal neuralgia (TN) is a specific type of neuropathic orofacial pain of which the plasticity of brain structure and connectivity have remained largely unknown. A total of 62 TN patients were included and referred to MRI scans. Voxel‐based morphometry was used to analyze the change of gray matter volume. Resting‐state functional imaging was used to analyze the connectivity between brain regions. The results showed gray matter volume reduction in components of the prefrontal cortex, precentral gyrus, cerebellar tonsil, thalamus, hypothalamus, and nucleus accumbens among right TN patient and in the inferior frontal gyrus, precentral gyrus, cerebellum, thalamus, ventral striatum, and putamen among left TN patients. The connections between the right superior frontal gyrus and right middle frontal gyrus were lower in right TN patients. The connection between the left precentral gyrus and the left superior frontal gyrus was lower while the connection between bilateral thalamus was higher in left TN patients. The changes of volume in bilateral thalamus of right TN patients and left ventral striatum of left TN patients, and the connectivity between bilateral thalamus of left TN patients were moderately correlated with pain duration. These findings suggest that brain regions such as the thalamus may not only be involved in processing of pain stimuli but also be important for the development of TN. The left hemisphere may be dominant in processing and modulation of TN pain signal. Chronification of TN induces volume changes in brain regions which are associated with emotional or cognitive modulation of pain. Hum Brain Mapp 39:609–621, 2018. © 2017 Wiley Periodicals, Inc.     

Putaminal gray matter volume decrease in panic disorder: an optimized voxel-based morphometry study

Our study aimed to identify gray matter volume differences between panic disorder patients and healthy volunteers using optimized voxel-based morphometry. Gray matter volume was compared between 18 panic subjects and 18 healthy volunteers. Panic disorder severity scale (PDSS) and Zung self-rating anxiety scale (Z-SAS) were administered. Gray matter volumes of bilateral putamen were decreased in panic subjects relative to healthy comparison subjects (corrected P < 0.05). Decreased gray matter volume was also observed in the right precuneus, right inferior temporal gyrus, right inferior frontal gyrus, left superior temporal gyrus, and left superior frontal gyrus at a less conservative level of significance. PDSS score negatively correlated with gray matter volume in the left putamen, right putamen, right inferior frontal gyrus, and left superior frontal gyrus in panic subjects. The duration of illness negatively correlated with left putaminal gray matter volume. There was also a negative correlation between gray matter volume in right putamen and Z-SAS score in panic subjects. The current study reports a putaminal gray matter volume decrease in panic subjects, which may be related to the clinical severity of panic disorder.     

Correlations between clinical symptoms, working memory functions and structural brain abnormalities in men with schizophrenia

Thirteen male patients with schizophrenia and thirteen male normal control subjects were compared by magnetic resonance imaging (MRI) on volumes of the straight gyrus (SG), anterior cingulate gyrus, middle frontal gyrus, hippocampus, third ventricle, cavum septi pellucidi, total brain volume and intracranial volume. In addition, neuropsychological tasks were used to measure working memory and executive functions. Healthy volunteers and schizophrenic patients showed no significant differences in mean values for volumes of regions of interests. In the case of the SG, we found a significant difference in laterality: the tendency toward left dominance in healthy volunteers changed to significant right dominance in patients. The schizophrenic patients showed lower performance in working memory tasks, and strongly significant group differences were observed in measures of neurological signs assessed by the Neurological Evaluation Scale (NES). Negative symptoms correlated with the level of spatial working memory and executive functions. Negative symptoms also correlated with the volume of the right hippocampus, while the rate of anhedonia negatively correlated with the relative volume of the left SG.     

Clinical study of cerebral blood flow in unilateral chronic subdural hematoma measured by 99mTc-HMPAO SPECT]

Cerebral blood flow (CBF) measured by 99mTc-HMPAO SPECT before operation was studied in 60 patients with unilateral chronic subdural hematoma. The regional CBF was measured in 26 regions of the fronto-occipital 10 cortices, putamen, thalamus and cerebellar hemisphere on both sides. Sixty cases with unilateral chronic subdural hematoma were classified into four groups on the basis of clinical symptoms: 17 cases with headache (headache group), 34 cases with hemiparesis (hemiparesis group) and 9 cases with consciousness disturbance or dementia (consciousness disturbance group), and into three groups on the basis of the degree of midline brain shift on MRI: 7 cases of mild shift group, 24 cases of moderate shift group and 29 cases of severe shift group. The average CBF in 60 patients in each region indicated that the regional CBF was reduced in frontal, occipital cortices and cerebellum on the non-hematoma side, and in putamen and thalamus on the hematoma side. In the headache group, the regional CBF reduction on the non-hematoma side was found in only frontal and occipital cortices compared with the corresponding regions on the hematoma side. In the hemiparesis group, the regional CBF was reduced in frontal and occipital cortices on the non-hematoma side and in putamen and thalamus on the hematoma side. The part of CBF reduction in both hemispheres was also noted in the hemiparesis group. In the consciousness disturbance group, the CBF reduction was markedly noted in whole brain. The CBF reductions in frontal and occipital cortices on the non-hematoma side and in putamen, thalamus and cerebellum on the hematoma side was not mutually related with the degree of midline brain shift. We concluded that the disturbance of CBF in chronic subdural hematoma was started from frontal and occipital cortices on the non-hematoma side observed in the headache group, and which was extended to putamen and thalamus on the hematoma side and a part of both hemispheres observed in the hemiparesis group. And such disturbance was finally observed as the CBF reductions in whole brain in the consciousness disturbance group.     

Elevated thalamic and prefrontal regional cerebral blood flow in obsessive-compulsive disorder: a SPECT study

Functional neuroimaging studies have pointed to a possible role of cerebral circuits involving the prefrontal and anterior cingulate cortices, the striatum, and thalamus in the pathophysiology of obsessive-compulsive disorder (OCD). Regional cerebral blood flow (rCBF) of 16 drug-free Brazilian patients with OCD and 17 healthy subjects matched for age, gender, handedness and level of education was measured with [99m-Tc] HMPAO single photon emission computed tomography. Analysis of covariance identified four regions of interest with significantly higher rCBF: the right superior and inferior frontal cortex and the right and left thalamus. Positive correlations between symptom severity measured by Clinical Global Impression scores and rCBF were found in the right and left inferior frontal lobes and in the right basal ganglia. Compulsive behavior was inversely correlated with rCBF in the right thalamus, and duration of illness correlated positively with rCBF in the right and left superior frontal lobes and with the right thalamus. The findings of this SPECT study conducted in Brazil are in agreement with prior studies and provide additional support for the involvement of prefrontal-subcortical circuits in the pathophysiology of OCD. Furthermore, the study suggests that similar brain mechanisms appear to be involved cross-culturally.     

脑卒中后抑郁合并认知损害的磁共振扩散张量成像研究

目的 探讨脑卒中后抑郁(PSD)合并卒中后认知功能损害(PSCI)患者的磁共振扩散张量成像(DTI)表现及脑卒中后抑郁合并认知功能损害的发病机制。方法 选取武汉大学中南医院2014年10月～2015年12月首发急性脑卒中患者52例,进行汉密尔顿抑郁量表(HAMD)、简明精神状态检查量表(MMSE)、蒙特利尔认知评估(MoCa)量表评分,分为PSD合并PSCI组13例(A组),PSD组(B组)11例,PSCI组(C组)12例,单纯脑卒中组16例(D组)。进行磁共振平扫及DTI扫描,比较各组不同部位FA值的差异。结果 A组与D组比较,双侧额叶、双侧半卵圆中心、左侧颞叶、左侧丘脑、右侧壳核FA值减低,差异有统计学意义(P<0.05)。结论 PSD合并PSCI患者可能具有相对独立的发病机制,与双侧额叶、双侧半卵圆中心、左侧颞叶、左侧丘脑及右侧壳核损害有关。     

Neural correlates of verbal semantic memory in patients with temporal lobe epilepsy

Functional imaging data suggest that the core network engaged in verbal semantic memory (SM) processing encompasses frontal and temporal lobe structures, with a strong left lateralization in normal right handers. The impact of long term temporal lobe epilepsy (TLE) on this network has only partly been elucidated. We studied verbal SM in 50 patients with chronic, intractable TLE (left TLE=26, right TLE=24) and 35 right handed normal controls using a verbal fMRI semantic decision paradigm. All patients had language lateralized to the left hemisphere, as verified by the intracarotid amobarbital procedure. Within and between group analyses showed remarkable, group-specific activation profiles. The control group activated frontal and temporal areas bilaterally, with a strong left predominance. Left TLE patients showed a shift of activations of left frontal and medial temporal areas to homologous regions in the right hemisphere. Furthermore, left TLE subjects utilized subcortical structures such as the thalamus and putamen to accomplish the verbal SM task. Contrastively, the activation pattern of right TLE patients resembled that of normal controls, but exhibited "hypofrontality" with a shift from frontal to posterior regions in the temporal, parietal and occipital lobe. Our results show that chronic epileptic activity originating from temporal seizure foci is associated with an alteration of neural circuits which support semantic language processing and that side of seizure focus has a specific impact on the resulting activation network. These findings presumably result from morphological changes and from functional reorganization which are both inherent to chronic TLE.     

Frontal lobe volumes in schizophrenia: effects of stage and duration of illness

While the changes in the volume of the temporal lobe and its sub-regions over the course of illness have been studied in patients with schizophrenia, few studies have examined changes in the frontal lobe between the first episode and the chronic stage. In this study, we focussed on the effect of illness stage and duration of illness on the volume of frontal lobe regions, though we also examined several other regions to establish the specificity of any effects, if observed, in this region. We compared the volumes of brain regions among 34 first-episode schizophrenia patients, 49 chronic schizophrenia patients, 18 healthy controls matched, on average, to the first-episode patients and 21 healthy controls matched, on average, to the chronic patients. Logarithmic regression analyses examined the relationships between the duration of illness and the brain regional volumes in the patient group. The results showed that chronic patients had smaller prefrontal cortical grey matter volumes, but larger premotor cortical and putamen volumes compared to first-episode patients and matched healthy controls. Although there were significant patient-by-control group interactions in the cerebellum and sensori-motor cortical grey matter volumes, these did not survive correction for multiple comparisons. There was a significant exponential relation between the duration of illness and the volumes of prefrontal cortex, parieto-occipital cortex grey matter, thalamus and putamen, suggesting that these regions are susceptible to change as the disorder persists. The enlargement of the premotor cortex and putamen are likely to be a result of antipsychotic medication.     

Supporting evidence for the model of cognitive dysmetria in schizophrenia--a structural magnetic resonance imaging study using deformation-based morphometry

The aim of the study was to investigate whether there is any structural evidence for the model of 'cognitive dysmetria' in schizophrenia if an automatic whole-brain analysis method is used. High-resolution magnetic resonance scans were obtained for 75 schizophrenic patients and 75 controls. These data were analysed using the recently developed deformation-based morphometry allowing the assessment of volumetric differences without a priori definition of regions of interest. When compared with controls, we found reduced volumes in patients with schizophrenia in the frontal lobe (gyrus frontalis superior, medius and medialis), the temporal lobe (gyrus temporalis superior and inferior), the thalamus, the left cerebellar hemisphere and the right cerebellar vermis. There was an increase in volume in the right putamen. To date, this is the first structural magnetic resonance imaging study to demonstrate that the three key-elements of the model of cognitive dysmetria--frontal lobe, thalamus, and cerebellum--are reduced in volume in schizophrenic patients. This highlights the importance of this concept for future investigations.     

Neural correlates of verbal semantic memory in patients with temporal lobe epilepsy

Functional imaging data suggest that the core network engaged in verbal semantic memory (SM) processing encompasses frontal and temporal lobe structures, with a strong left lateralization in normal right handers. The impact of long term temporal lobe epilepsy (TLE) on this network has only partly been elucidated. We studied verbal SM in 50 patients with chronic, intractable TLE (left TLE = 26, right TLE = 24) and 35 right handed normal controls using a verbal fMRI semantic decision paradigm. All patients had language lateralized to the left hemisphere, as verified by the intracarotid amobarbital procedure. Within and between group analyses showed remarkable, group-specific activation profiles. The control group activated frontal and temporal areas bilaterally, with a strong left predominance. Left TLE patients showed a shift of activations of left frontal and medial temporal areas to homologous regions in the right hemisphere. Furthermore, left TLE subjects utilized subcortical structures such as the thalamus and putamen to accomplish the verbal SM task. Contrastively, the activation pattern of right TLE patients resembled that of normal controls, but exhibited ‘hypofrontality’ with a shift from frontal to posterior regions in the temporal, parietal and occipital lobe. Our results show that chronic epileptic activity originating from temporal seizure foci is associated with an alteration of neural circuits which support semantic language processing and that side of seizure focus has a specific impact on the resulting activation network. These findings presumably result from morphological changes and from functional reorganization which are both inherent to chronic TLE.     

Voxel-based analyses of gray/white matter volume and diffusion tensor data in major depression

The purpose of this study is to use voxel-based analysis to simultaneously elucidate regional changes in gray/white matter volume, mean diffusivity (MD), and fractional anisotropy (FA) in patients with unipolar major depressive disorder. We studied 21 right-handed patients and 42 age- and gender-matched right-handed normal subjects. Local areas showing significant gray matter volume reduction in depressive patients compared with controls were observed in the right parahippocampal gyrus, hippocampus, bilateral middle frontal gyri, bilateral anterior cingulate cortices, left parietal and occipital lobes, and right superior temporal gyrus. Local areas showing an increase of MD in depressive patients were observed in the bilateral parahippocampal gyri, hippocampus, pons, cerebellum, left frontal and temporal lobes, and right frontal lobe. There was no significant difference between the two groups for FA and white matter volume in the entire brain. Although there was no local area where brain volume and MD were significantly correlated with disease severity, FA tended to correlate negatively with total days depressed in the right anterior cingulate and the left frontal white matter. These results suggest that the frontolimbic neural circuit might play an important role in the neuropathology of patients with major depressive disorder.     

阿尔茨海默病的脑血流灌注研究

目的探讨AD患者脑血流灌注的特征性变化。方法选择20例确诊AD患者和10例认知正常者,对所有入组对象行SPECT脑血流灌注显像检查,对所得图像进行视觉分析和半定量分析,比较两组对象各脑区血流灌注情况的差异,并比较AD患者左、右脑叶脑血流灌注的差异。结果 (1)视觉分析结果显示,AD组以颞叶或顶叶脑血流灌注减低为主,各占55%,其中双侧颞顶叶血流灌注减低者占15%,单侧颞顶叶血流灌注减低占20%。正常认知组SPECT影像学表现各异,额叶、颞叶、顶叶、枕叶、丘脑、基底节血流灌注减少情况均存在,各占10%。但无双侧颞顶叶血流灌注减少者,40%表现完全正常。(2)半定量分析结果显示,AD组在右额叶、双侧颞顶叶、右枕叶血流灌注显著低于正常认知组(P<0.05),以右侧颞叶血流灌注降低最明显,左右颞顶叶血流低灌注程度对比无显著性差异。结论 AD患者的SPECT特征性表现为双侧对称性颞顶叶血流低灌注,其中右侧颞叶血流灌注下降最严重。     

Structural neuroimaging in adolescents with a first psychotic episode

OBJECTIVE: The objective of the present study is to replicate findings in first-episode psychosis reporting a smaller volume in brain structures in a population with adolescent onset. METHOD: Magnetic resonance imaging studies were performed on 23 psychotic adolescents (12-18 years old, 17 males, 6 females) consecutively admitted to an adolescent inpatient unit and on 37 normal controls (13-18 years, 23 males, 14 females) matched for age, sex, and years of education. Diagnosis was made at baseline on the basis of the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version and confirmed after 12 months of follow-up. Total brain volume and gray matter, white matter, and cerebrospinal fluid (CSF) volumes of the frontal, parietal, temporal, and occipital lobes were measured bilaterally using a segmentation method based on the Talairach grid system. RESULTS: Male patients showed significantly larger volumes than did male controls in overall CSF and left frontal and right parietal sulci CSF. Male patients also showed significantly lower volumes of gray matter in the right and left frontal lobes. No significant volumetric differences were found in females. There were no differences between individuals with a diagnosis of schizophrenia at follow-up and the rest of the patients. CONCLUSIONS: This study suggests that larger CSF and lower gray matter volumes in the frontal lobes may be a nonspecific vulnerability marker for psychosis in male adolescents.     

Structural and functional brain alterations in patients with idiopathic rapid eye movement sleep behavior disorder

ObjectiveTo investigate structural and functional alterations in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) compared with healthy controls.MethodsTwenty-seven patients with polysomnography-confirmed iRBD and 33 healthy subjects were recruited. All subjects underwent a 3-tesla structural and resting-state functional magnetic resonance imaging (fMRI) examination. Voxel-based morphometry (VBM) analysis was performed to assess grey matter alterations between groups. The amplitude of low-frequency fluctuations (ALFF) was calculated and then compared to measure differences in spontaneous brain activity. Correlations were performed to explore associations between imaging metrics and clinical characteristics in iRBD patients.ResultsCompared with healthy controls, patients with iRBD had decreased grey matter volume in the frontal, temporal, parietal, occipital cortices as well as increased grey matter volume in cerebellum posterior lobe, putamen, and thalamus. Patients with iRBD also exhibited increased ALFF values in the right parahippocampal gyrus. Olfaction correlated with ALFF value changes in occipital cortices.ConclusionsPatients with iRBD had widespread decreases of grey matter volume. Increases of grey matter volume in cerebellum, putamen, and thalamus may suggest a compensatory effect, while the altered ALFF values in parahippocampal gyrus and occipital cortices may play a role in the underlying process of neurodegeneration in this disorder.     

Volumes of hippocampus, amygdala and frontal lobes in the MRI-based diagnosis of early Alzheimer's disease: Correlation with memory functions

Summary We studied the usefulness of measuring volumes of the hippocampus, amygdala and frontal lobes with coronal magnetic resonance imaging (MRI) scans in the diagnosis of early Alzheimer's disease (AD). We examined 32 patients diagnosed according to the NINCDS-ADRDA criteria of probable AD and 16 age-matched healthy cognitively normal controls. The AD patients had mild dementia with a mean score of 22.8 in the Mini-Mental Status Examination (MMSE). We used a 1.5T magnetic resonance imager and normalized the volumes for brain area. The AD patients had significantly smaller volumes of the right and the left hippocampus (–38%) (ANOVA, p<0.001) and the left frontal lobe (–16%, p<0.05) compared to controls. The reductions in volumes of the right frontal lobe (–13%), the right amygdala (–14%) or the left amygdala (–18%) were not statistically significant. In the discriminant function analysis which included the volumes of the hippocampus, amygdala, and the frontal lobes and age, the volumes of the left and right hippocampus, the left and right frontal lobe, and the right amygdala entered the model and we could correctly classify 92% of the subjects into AD and control groups (Chi-square 42.6, df 5, p<0.0001). By using the volumes of the hippocampus, the frontal lobes or the amygdala on their alone, the correct classification was achieved in 88%, 65% and 58% of the subjects, respectively. In addition, in AD patients the volumes of the left hippocampus correlated significantly with the MMSE score and with immediate and delayed verbal memory; the smaller the volume the more impaired was their performance. Our data indicate that measurements of volumes of the hippocampus might be useful in diagnosis of early AD.     

Association of depression duration with reduction of global cerebral gray matter volume in female patients with recurrent major depressive disorder

OBJECTIVE: The authors investigated the relationship between depression duration and cerebral gray matter volume in female patients with recurrent major depressive disorder. METHOD: Magnetic resonance imaging was used to measure intracranial and total brain volumes as well as gray matter and white matter volumes of the cerebrum; frontal, temporal, parietal, and occipital lobes; cerebellum; and the lateral and third ventricles in 23 female patients with DSM-IV major depression. RESULTS: Correlation and regression analyses showed a significant relationship between total illness duration and cerebral gray matter (including cortical lobe) volume after correction for intracranial volume and age. CONCLUSIONS: Depressive states may lead to changes in global cerebral gray matter volume.     

Structural brain abnormalities in patients with vestibular migraine

New advances in understanding the pathophysiology of vestibular migraine (VM) have suggested a large overlap between migraine and vestibular pathways. We explored the regional distribution of gray (GM) and white matter (WM) abnormalities in VM patients in comparison to migraine patients with (MWA) and without aura (MWoA) and their correlations with patients’ clinical manifestations. Using a 3.0 Tesla scanner, brain T2-weighted and 3D T1-weighted MRI scans were acquired from 19 VM, 19 MWA, 19 MWoA and 20 age-matched controls. GM and WM volumetric abnormalities were estimated using voxel-based morphometry (SPM12). Compared to controls, migraine patients had decreased GM volume of the left cerebellum and an increased GM volume of the left temporal lobe. VM patients had a selective GM volume increase of frontal and occipital regions compared to controls and the other two groups of migraineurs and no regions with decreased GM volume. Compared to MWoA and MWA, VM had increased GM volume of the left thalamus. Regional GM abnormalities did not correlate with disease duration and attack frequency. No WM volumetric differences were detected between migraine patients and controls. These results show that GM volume abnormalities of nociceptive and multisensory vestibular brain areas occur in VM patients. Overall, our findings suggest that an abnormal brain sensitization might lead to a dismodulation of multimodal sensory integration and processing cortical areas in VM patients.     

Asymmetric Gray Matter Volume Changes Associated with Epilepsy Duration and Seizure Frequency in Temporal-Lobe-Epilepsy Patients with Favorable Surgical Outcome

MethodsVBM analysis of brain MRI using statistical parametric mapping 8 (SPM8) was performed for 30 left MTLE (LMTLE) and 30 right MTLE (RMTLE) patients and 30 age- and sex-matched healthy controls. We also analyzed the correlations between GMV changes and clinical features of MTLE patients.ResultsIn SPM8-based analyses, MTLE patients showed significant GMV reductions in the hippocampus ipsilateral to the epileptic focus, bilateral thalamus, and contralateral putamen in LMTLE patients. The GMV reductions were more extensive in the ipsilateral hippocampus, thalamus, caudate, putamen, uncus, insula, inferior temporal gyrus, middle occipital gyrus, cerebellum, and paracentral lobule in RMTLE patients. These patients also exhibited notable reductions of GMV in the contralateral hippocampus, thalamus, caudate, putamen, and inferior frontal gyrus. We observed that GMV reduction was positively correlated with several clinical features (epilepsy duration and seizure frequency in RMTLE, and history of febrile seizure in LMTLE) and negatively correlated with seizure onset age in both the RMTLE and LMTLE groups.ConclusionsOur study revealed GMV decreases in the hippocampus and extrahippocampal regions. Furthermore, the GMV reduction was more extensive in the RMTLE group than in the LMTLE group, since it included the contralateral hemisphere in the former. This difference in the GMV reduction patterns between LMTLE and RMTLE may be related to a longer epilepsy duration and higher seizure frequency in the latter.