Volumetric changes in hypothalamic subunits in patients with relapsing remitting multiple sclerosis.

PURPOSE: Studies on hypothalamic changes in patients with relapsing remitting multiple sclerosis (RRMS) are very scarce, despite the fact that the relationship with the hypothalamus is frequently reported. The aim of the study was to determine the volume of the hypothalamic subunits and the total hypothalamus and its relationship with the total demyelinating lesion volume (TLV) and expanded disability status scale (EDSS) in RRMS patients. METHODS: In this cross-sectional study, anterior-superior, superior tubular, posterior hypothalamus, anterior-inferior, inferior tubular subunits of hypothalamus, and total hypothalamus volume were calculated, with fully automatic analysis methods using volumetric T1 images of 65 relapsed RRMS patients and 68 healthy controls (HC). Volume changes in the hypothalamus and its subunits in RRMS patients were examined using multivariate analysis of covariance (MANCOVA). The relationship of these volumes with EDSS and TLV was investigated by partial correlation analysis. RESULTS: There is volume reduction in total hypothalamus (F = 13.87, p < 0.001), anterior-superior (F = 19.2, p < 0.001), superior tubular (F = 10.1, p = 0.002) subunits, and posterior hypothalamus (F = 19.2, p < 0.001) volume in RRMS patients. EDSS correlates negatively with anterior-superior (p = 0.017, r = - 0.333), superior tubular subunits (p = 0.023, r = - 0.439), posterior hypothalamus (p < 0.001, r = - 0.511), and whole hypothalamus volume (p = 0.001, r = - 0.439). TLV correlates negatively with anterior superior (p < 0.001, r = - 0.565), anterior inferior (p = 0.002, r = - 0.431), superior tubular subunits (p = 0.002, r = - 0.432), posterior hypothalamus (p < 0.001, r = - 0.703), and whole hypothalamus (p < 0.001, r = - 0.627) volumes. CONCLUSION: This study demonstrates a reduction in total hypothalamus volume, anterior-superior, superior tubular, and posterior hypothalamus in patients with RRMS. Anterior-superior and superior tubular subunit, posterior hypothalamus, and total hypothalamus volume were negatively correlated with TLV and EDSS scores.

Cortical morphological changes in multiple sclerosis patients: a study of cortical thickness, sulcal depth, and local gyrification index.

PURPOSE: Multiple sclerosis (MS) is a disease that progresses not only with demyelination but also with neurodegeneration. One of the goals of drug treatment in MS is to prevent neurodegeneration. Cortical thickness (CT), sulcal depth (SD), and local gyrification index (LGI) are indicators related to neurodegeneration. The aim of this study is to investigate changes in CT, SD, and LGI in patients with relapsing-remitting MS (RRMS). METHODS: T1 images of 74 RRMS patients and 65 healthy controls were used. T1 hypointense areas in RRMS patients were corrected using fully automated methods. CT, SD, and LGI were calculated for each patient. RESULTS: RRMS patients showed widespread cortical thinning, especially in bilateral temporoparietal areas, decreased SD in bilateral supramarginal gyrus, superior temporal gyrus, postcentral gyrus, and transverse temporal gyrus, and decreased LGI, especially in the left posterior cingulate gyrus and insula. The decrease in cortical thickness was associated with the number of attacks and lesion volume. EDSS was related to CT in the right lingual, inferior temporal, and fusiform gyrus. The LGI was correlated with T2 lesion volume in bilateral insula, with EDSS in the right insula and transverse and superior temporal gyri, and with the number of attacks in the right paracentral gyrus and pre-cuneus. However, SD did not show any correlation with EDSS, T2 lesion volume, or the number of attacks. CONCLUSION: Our results demonstrate widespread cortical thinning, decreased sulcal depth in local areas, and decreased gyrification in folds in RRMS patients, which are related to clinical parameters.

Microstructural white matter abnormalities in hypothyroidism evaluation with diffusion tensor imaging tract-based spatial statistical analysis.

PURPOSE: Hypothyroidism is presented in a wide range from neuropsychiatric problems including depression, memory and cognitive disorders to poor motor coordination. Against the background of morphologic, functional and molecular changes on the white and grey matter of the brain, we aimed to investigate the effects of hypothyroidism on white matter (WM) integrity using tract-based spatial statistics (TBSS). METHODS: Eighteen patients with hyperthyroidism and 14 age-sex-matched healthy control subjects were included in this study. TBSS was used in the diffusion tensor imaging study for whole-brain voxel wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) of WM. RESULTS: When compared to the control group, the whole brain TBSS revealed extensive reductions of FA in the supratentorial WM including corticospinal tract, posterior limb of the internal capsule (PLIC), uncinate fasciculus, inferior longitudinal fasciculus (p < 0.005). The ROI analyses showed RD increment of superior longitudinal fasciculus, AD decrement of cingulum (CIN), external capsule, PLIC and corpus callosum (CC) in patients with hypothyroidism (p < 0.005). Autoimmune and non-autoimmune hypothyroidism patient subgroups showed a significant difference in terms of hippocampus FA, CIN MD, CC MD, CC AD, CIN RD, SLF RD, CC RD (p < 0.005). CIN FA values showed a negative correlation with the Beck Depression Inventory (p = 0.007, r = - 852). CONCLUSIONS: These preliminary results of TBSS analyses represented FA and AD decrement, and RD increment in several WM tracts and indicates the demyelination process underlying pathophysiology of clinical aspects of hypothyroidism.

Diffusion tensor imaging in hyperthyroidism: assessment of microstructural white matter abnormality with a tract-based spatial statistical analysis.

BACKGROUND: Metabolic, morphological, and functional brain changes associated with a neurological deficit in hyperthyroidism have been observed. However, changes in microstructural white matter (WM), which can explain the underlying pathophysiology of brain dysfunctions, have not been researched. PURPOSE: To assess microstructural WM abnormality in patients with untreated or newly diagnosed hyperthyroidism using tract-based spatial statistics (TBSS). MATERIAL AND METHODS: Eighteen patients with hyperthyroidism and 14 age- and sex-matched healthy controls were included in this study. TBSS were used in this diffusion tensor imaging study for a whole-brain voxel-wise analysis of fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD) of WM. RESULTS: When compared to the control group, TBSS showed a significant increase in the RD of the corpus callosum, anterior and posterior corona radiata, posterior thalamic radiation, cingulum, superior longitudinal fasciculus, and the retrolenticular region of the internal capsule in patients with hyperthyroidism (P < 0.05), as well as a significant decrease in AD in the anterior corona radiata and the genu of corpus callosum (P < 0.05). CONCLUSION: This study showed that more regions are affected by the RD increase than the AD decrease in the WM tracts of patients with hyperthyroidism. These preliminary results suggest that demyelination is the main mechanism of microstructural alterations in the WM of hyperthyroid patients.

Olfactory Bulb Microstructural Changes in Patients With Nasal Septum Deviation.

OBJECTIVE: The aim of this study is to assess the microstructural changes to the olfactory bulb (OB) in patients with nasal septum deviation (NSD) using diffusion tensor imaging and to research the association between these changes and the degree of NSD. METHODS: Ninety-six patients with NSD (46 males, 50 females) who received diffusion tensor imaging were assessed by 2 independent readers. The patients were separated into 3 groups according to the NSD angle. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the ipsilateral and contralateral OB were measured in all NSD patients by region of interest. RESULTS: According to deviation side, there was significant difference between the right (R) and left (L) OB FA and ADC values across the 3 groups. In patients with left- and right- sided NSD, FA and ADC values for the left and right OB were significantly different between groups 1 and 3, and groups 2 and 3. There was negative correlation between L-FA (r = -0.481, P = 0.001; r = -0.496, P = 0.001) and R-FA (r = -0.705, P = 0.001; r = -0.286, P = 0.02) versus age and deviation angle. However, there was positive correlation between L-ADC versus age and deviation angle (r = 0.493, P = 0.001; r = 0.482, P = 0.001), as well as positive correlation between R-ADC versus age (r = 0.646, P = 0.001). CONCLUSION: This is the first study showing ADC increase and FA decrease associated with axonal damage and microstructural integrity loss based on the side of deviation in NSD patients. It has also shown that this abnormality is directly proportional with NSD degree.

Multiparametric MRI in differentiating solitary brain metastasis from high-grade glioma: diagnostic value of the combined use of diffusion-weighted imaging, dynamic susceptibility contrast imaging, and magnetic resonance spectroscopy parameters.

OBJECTIVE: The purpose of this study was to determine whether the combined use of diffusion weighted imaging (DWI), magnetic resonance spectroscopy (MRS), and dynamic susceptibility contrast imaging (DSCI) parameters could provide a more accurate diagnosis in the differentiation of high-grade glioma (HGG) from solitary brain metastasis (SBM) in the enhancing tumour and in the peritumoural region. MATERIALS AND METHODS: Fifty-six patients who received DWI, DSCI, and MRS before surgery were assessed. In differentiating SBM from HGG, the cutoff values of the DWI-apparent diffusion coefficient (ADCmin, ADCmax, and ADCmean), DSCI-relative cerebral blood volume (rCBV), and MRS-Cho/Cr, Cho/NAA, and NAA/Cr parameters for the peritumoural region were determined with ROC. The combined ROC curve was used for the different combinations of the peritumoural region DWI, DSCI, and MRS parameters in differentiating between the two tumours, and the best model combination was formed. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments. This study was approved by the Institutional Review Board at our institutes. RESULTS: In the enhancing tumour, all the parameters except NAA/Cr (P = 0.024) exhibited no statistical difference in differentiating between these two groups (P > 0.05). AUC values for ADCmin, ADCmax, ADCmean, rADCmin, rADCmax, rADCmean, rCBV, Cho/Cr, Cho/NAA, and NAA/Cr parameters in the peritumoural region in differentiating SBM from HGG were 0.860, 0.822, 0.848, 0.822, 0.801, 0.822, 0.906, 0.851, 0.903, and 0.784, respectively. In differentiating HGG from SBM, the best model consisted of the combination of peritumoural ADCmin, rCBV, and Cho/NAA parameters. AUC values were 0.970. CONCLUSIONS: The combination of peritumoural region ADCmin, rCBV, and Cho/NAA parameters can help in differentiating SBM from HGG, with a diagnostic accuracy of 97%.

Magnetic Resonance Imaging of Intracranial Hypotension: Diagnostic Value of Combined Qualitative Signs and Quantitative Metrics.

OBJECTIVE: The aim of this study was to investigate whether the use of combination quantitative metrics (mamillopontine distance [MPD], pontomesencephalic angle, and mesencephalon anterior-posterior/medial-lateral diameter ratios) with qualitative signs (dural enhancement, subdural collections/hematoma, venous engorgement, pituitary gland enlargements, and tonsillar herniations) provides a more accurate diagnosis of intracranial hypotension (IH). METHODS: The quantitative metrics and qualitative signs of 34 patients and 34 control subjects were assessed by 2 independent observers. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of quantitative metrics and qualitative signs, and for the diagnosis of IH, optimum cutoff values of quantitative metrics were found with ROC analysis. Combined ROC curve was measured for the quantitative metrics, and qualitative signs combinations in determining diagnostic accuracy and sensitivity, specificity, and positive and negative predictive values were found, and the best model combination was formed. RESULTS: Whereas MPD and pontomesencephalic angle were significantly lower in patients with IH when compared with the control group (P < 0.001), mesencephalon anterior-posterior/medial-lateral diameter ratio was significantly higher (P < 0.001). For qualitative signs, the highest individual distinctive power was dural enhancement with area under the ROC curve (AUC) of 0.838. For quantitative metrics, the highest individual distinctive power was MPD with AUC of 0.947. The best accuracy in the diagnosis of IH was obtained by combination of dural enhancement, venous engorgement, and MPD with an AUC of 1.00. CONCLUSIONS: This study showed that the combined use of dural enhancement, venous engorgement, and MPD had diagnostic accuracy of 100 % for the diagnosis of IH. Therefore, a more accurate IH diagnosis can be provided with combination of quantitative metrics with qualitative signs.

Structural brain alterations of Down's syndrome in early childhood evaluation by DTI and volumetric analyses.

OBJECTIVES: To provide an initial assessment of white matter (WM) integrity with diffusion tensor imaging (DTI) and the accompanying volumetric changes in WM and grey matter (GM) through volumetric analyses of young children with Down's syndrome (DS). METHODS: Ten children with DS and eight healthy control subjects were included in the study. Tract-based spatial statistics (TBSS) were used in the DTI study for whole-brain voxelwise analysis of fractional anisotropy (FA) and mean diffusivity (MD) of WM. Volumetric analyses were performed with an automated segmentation method to obtain regional measurements of cortical volumes. RESULTS: Children with DS showed significantly reduced FA in association tracts of the fronto-temporo-occipital regions as well as the corpus callosum (CC) and anterior limb of the internal capsule (p < 0.05). Volumetric reductions included total cortical GM, cerebellar GM and WM volume, basal ganglia, thalamus, brainstem and CC in DS compared with controls (p < 0.05). CONCLUSION: These preliminary results suggest that DTI and volumetric analyses may reflect the earliest complementary changes of the neurodevelopmental delay in children with DS and can serve as surrogate biomarkers of the specific elements of WM and GM integrity for cognitive development. KEY POINTS: • DS is the most common genetic cause of intellectual disability. • WM and GM structural alterations represent the neurological features of DS. • DTI may identify the earliest aging process changes. • DTI-volumetric analyses can serve as surrogate biomarkers of neurodevelopment in DS.

Magnetic Resonance Imaging Evidence of Varicella Zoster Virus Polyneuropathy: Involvement of the Glossopharyngeal and Vagus Nerves Associated With Ramsay Hunt Syndrome.

The involvement of lower cranial nerve palsies is less frequent in Ramsay Hunt syndrome caused by varicella zoster virus (VZV). The authors report 1 of extremely rare patients of radiologically proven polyneuropathy of VZV infection with magnetic resonance imaging findings of VII, IX, and X cranial nerve involvement is a 62-year-old female patient, who initially presented with Ramsay Hunt syndrome. Varicella zoster virus infection should be considered even in patients who show unilateral palsy of the lower cranial nerves associated with laryngeal paralysis. Thin-section T2W and T1W images with a contrast agent should be added to the imaging protocol to show the subtle involvement.

Spontaneous Epidural Pneumocephalus.

Spontaneous epidural pneumocephalus is a rare condition. The authors reported a 35-year-old male patient with tinnutus, dull headache, and swelling on his head. Patient had a history of head trauma and skull fracture from when he was 5 years old. Cranial computed tomography revealed increase in pneumatization of right mastoid air cells and large epidural air in temporoparietal region. Inner table of right temporal bone got thinner, causing communication of mastoid air cells with epidural space. Epidural air had septations and exerted mass effect on the right parietal lobe with minimal midline shift. Thinning of also right parietal bone caused extension of epidural air into the right parietal subcutaneous tissue and hence subcutaneous swelling. There was no obvious fracture line. Spontaneous epidural pneumocephalus is extremely rare condition that may cause severe complications. There are several etiologic factors. Head trauma can be the eliciting factor in the authors' patient. It is important to be familiar with its presentation and imaging findings to make early diagnosis and treatment.

The impact of the cochlear-carotid interval on tinnitus perception.

PURPOSE: We hypothesized that the cochlear-carotid interval (CCI), which is defined as the smallest distance along the petrous segment of the internal carotid artery and basal turn of cochlea, may be associated with direct stimulation of hair cells, thereby affecting tinnitus perception. The aim of this study was to investigate the relationships between the CCI, tinnitus perception, and accompanying hearing loss in patients with tinnitus. METHODS: The CCI on both sides was measured independently by two observers from the temporal 3D b-FFE MR images of 25 patients with tinnitus and 20 age/gender matched control subjects. The relationships between CCI, tinnitus visual analog scale (VAS), and tinnitus handicap inventory (THI) were investigated. RESULTS: CCI ranged 0.2-5.6 mm (1.9 ± 1.5) on the right and 0.1-5.4 mm (2.2 ± 1.6) on the left side in the patient group and 0.5-5.4 (1.9 ± 1.4) mm on the right and 0.3-6.7 (2.3 ± 1.7) on the left side in the control group. The differences between the two groups were not statistically significant (p > 0.05). CCI showed a strong negative correlation with THI and VAS scores on both sides. Correlation of audiologic findings with CCI revealed a significant negative correlation with pure tone average of the ipsilateral ear most affectedly at high frequencies. CONCLUSION: The strong negative correlation of CCI with tinnitus-related distress and accompanying sensorineural hearing loss predominantly at high frequencies suggests that further studies on patients with tinnitus that focus on this small area may help to improve the knowledge of tinnitus pathophysiology.

Volumetric analysis of the subthalamic and red nuclei based on magnetic resonance imaging in patients with Parkinson's disease.

Parkinson's disease (PD) is associated with degeneration of the dopaminergic neurons in the substantia nigra. The subthalamic nucleus (STN) plays a pivotal role in the pathogenesis. However, there is not much known about the morphological changes in the STN. The red nucleus (RN) has many connections with the motor coordinating pathways although it is not primarily involved in the pathogenesis. In this study we aimed to compare the volumes of the STN and RN measured by magnetic resonance imaging in PD patients and controls to investigate how these structures are affected at the morphological level. Twenty patients with PD and twenty age/sex matched controls were enrolled in this study. Severity score was determined by Hoehn & Yahr staging: 6 at stage II and 14 at stage III in med-off state. Imaging was performed by a 1.5 Tesla (T) MR scanner. Measurements of total brain and normalized STN and RN volumes were performed by manual planimetry using Image J software. No statistically significant differences were observed between two groups based on age or gender and disease stage and nuclei volumes. The total estimated brain volumes were not different between PD patients and controls. However, normalized volumes of the STN and RN were 14% and 16% larger, respectively, in PD patients compared to the controls (p < 0.05). Our findings suggest that the volumes of the STN and RN are increased in patients with PD. These changes possibly reflect the altered metabolic activity of these regions demonstrated by neurophysiological studies.

Primary malignant mucosal melanoma of the nasopharynx: an unusual cause of unilateral hearing loss.

There are many causes of unilateral hearing loss, and making the correct differential diagnosis, especially in elderly patients, is difficult. A primary malignant mucosal melanoma of the nasopharynx is extremely rare and can cause a variety of symptoms. Hearing loss, as a presenting symptom of mucosal malignant melanoma of the nasopharynx, has not yet been defined in the literature. Herein, we report a case of primary mucosal malignant melanoma of the nasopharynx presented with unilateral hearing loss in a 70-year-old man.

Diffusion tensor imaging in Behcet's disease with and without neurological involvement patients: evaluation of microstructural white matter abnormality with a tract-based spatial statistical analysis.

OBJECTIVE: This study aims to assess the microstructural abnormalities in white matter (WM) among Behcet's disease (BD) patients, both with and without neurological involvement, utilising tract-based spatial statistics (TBSS) to elucidate the underlying causes of WM microstructural changes. METHODS: This prospective study comprised 43 BD patients without neurological involvement, 15 neuro-Behcet's disease (NBD) patients with normal conventional MRI, and 54 healthy controls matched for age and sex. TBSS was applied in this diffusion tensor imaging study to conduct a whole-brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of WM. RESULTS: Compared to the control group, BD patients exhibited decreased FA and increased MD and RD in nearly all WM tracts, along with increased AD in the left corticospinal tract (CST), left inferior longitudinal fasciculus (ILF), and left superior longitudinal fasciculus (SLF). NBD patients also showed a widespread decrease in FA and increased MD and RD, similar to BD patients without neurological involvement. Additionally, NBD patients had increased AD in the left CST, left ILF, left SLF, left inferior fronto-occipital fasciculus (IFOF), and right CST. Compared to BD patients without neurological involvement, NBD patients exhibited a greater reduction in FA and an increase in MD and RD in WM tracts, with no significant differences in AD. CONCLUSION: These results suggest that the main mechanism of microstructural changes in the WM of BD patients may be related to impaired fibre integrity, demyelination, and decreased myelin sheath integrity. ADVANCES IN KNOWLEDGE: This study demonstrated BD patients without neurological involvement and NBD patients a decrease in FA and an increase in MD and RD were observed in larger areas of major WM tracts, while an increase in AD values was observed in fewer tracts. Our findings may be useful in understanding the pathophysiology underlying subclinical parenchymal involvement and neurological dysfunction in BD patients and the management of BD patients.

Advanced Diffusion MRI in the Differential Diagnosis of Hemorrhagic Cavernous Malformations in the Brain: A Case Report.

Cavernous malformations, low-flow vascular lesions predominantly found in the brain and occasionally in the spinal cord, can be congenital or acquired, with acquired forms often being single and congenital ones multiple. While many patients remain asymptomatic, hemorrhage from these lesions can lead to significant neurological symptoms. This case report describes a 35-year-old female with a hemorrhagic lesion in the right precentral gyrus, initially challenging to diagnose due to atypical imaging findings. Advanced magnetic resonance imaging (MRI) techniques, including dynamic susceptibility contrast perfusion and advanced diffusion methods, were employed to distinguish the lesion from other hemorrhagic conditions and suggested that the lesion is benign in nature. Follow-up MRI revealed regression of the hemorrhage and typical characteristics of a cavernous malformation. The case underscores the utility of advanced diffusion MRI techniques in differentiating hemorrhagic cavernous malformations from other pathologies, particularly in complex cases where conventional imaging may fall short.

Opposing effects of thyroid hormones on hypothalamic subunits and limbic structures in hyperthyroidism patients: A comprehensive volumetric study.

Thyroid hormones play a critical role in brain development, but paradoxically, patients with hyperthyroidism often exhibit cognitive decline and irritability. This study aims to explore the pattern of atrophy in hyperthyroid patients, changes in specific areas of the brain, including hypothalamic subfields and limbic structures, and their relationships with hormonal levels and psychometric tests. This prospective cross-sectional study involves 19 newly diagnosed, untreated hyperthyroid patients, and 15 age and gender-matched control subjects. The participants underwent psychometric and cognitive tests and volumetric MRI. The hypothalamic subfield (anterior-inferior, anterior-superior, superior-tubular, inferior-tubular, and posterior hypothalamus) and limbic structures (fornix, basal forebrain, nucleus accumbens, and septal nucleus) were segmented using voxel-based morphometry, surface-based morphometry, and deep learning algorithms. The groups were compared using the t-test, and correlation analyses were performed between clinical parameters and volumetric measurements. The correlation between hormonal parameters and volumetric measurements in patient and control groups was assessed with the Meng test. Hyperthyroid patients displayed widespread grey matter loss and sulcal shallowing in the left hemisphere. However, no local gyrification index changes or cortical thickness variations were detected. The limbic structures and hypothalamic subunits did not show any volume discrepancies. Free thyroxine in the patient group negatively correlated with bilateral anterior-inferior and right septal nucleus, but positively correlated with left anterior-inferior in the control group. Thyroid stimulating hormone in the patient group showed a positive correlation with bilateral fornix volume, a correlation absent in the control group. Disease duration negatively correlated with right anterior-inferior, right tubular inferior, and right septal nucleus. Changes in cognitive and psychometric test scores in the patient group correlated with the bilateral septal nucleus volume. Hyperthyroidism primarily leads to a reduction in grey matter volume and sulcal shallowing. Thyroid hormones have differing volumetric effects in limbic structures and hypothalamic subunits under physiological and hyperthyroid conditions.

Microstructural Abnormalities in the Contralateral Normal-appearing White Matter of Glioblastoma Patients Evaluated with Advanced Diffusion Imaging.

PURPOSE: Glioblastoma patients develop recurrence in the opposite hemisphere far from the primary tumor site even after complete resection. This is one of the main reasons for short disease survival. Our aim in this study is to detect microstructural changes in the contralateral hemisphere of glioblastoma patients using different diffusion models with the fully automated tract-based spatial statistics (TBSS) method. METHODS: Fourteen right-sided and eleven left-sided glioblastoma patients without any treatment and eighteen age- and gender-matched controls were included in the study. Multi-shell diffusion weighted images were created with a 3T MRI device. After various preprocessing steps, images of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), axial kurtosis (AK), mean kurtosis (MK), radial kurtosis (RK), intracellular volume fraction (ICVF), orientation dispersion index (ODI), and isotropic water fraction (ISO) were obtained. TBSS was used to compare diffusion tensor imaging, diffusion kurtosis imaging, and neurite orientation dispersion and density imaging parameters of right- and left-sided glioblastoma patients with the control group for the contralateral hemisphere. RESULTS: Both right-sided and left-sided glioblastoma patients have shown an increase in MD and ODI in the contralateral hemisphere. While right-sided glioblastoma patients showed an increase in RD, AD, and ISO in a more limited area in the contralateral hemisphere, left-sided glioblastoma patients showed an increase in MK and AK. FA, ICVF, and RK did not show any difference in both groups. CONCLUSION: There are microstructural changes in the contralateral hemisphere in glioblastoma patients, and these changes differ between right-sided and left-sided glioblastoma patients.

The role of MR diffusion kurtosis and neurite orientation dispersion and density imaging in evaluating gliomas.

BACKGROUND AND PURPOSE: Conventional MRI sequences in neuro-oncology are insufficient for glioma grading. However, newly developed diffusion-weighted imaging techniques have been shown to have a great potential for glioma grading. This study examined the diagnostic performance of diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), neurite orientation dispersion and density imaging (NODDI), and their combinations in glioma grading. METHODS: Multishell diffusion tensor images were obtained with 3T MRI in 38 glioma patients (22 high-grade glioma [HGG], 16 low-grade glioma [LGG]). DTI (fractional anisotropy [FA], mean diffusivity [MD], axial diffusivity [AD], radial diffusivity [RD]), DKI (Axial kurtosis [AK], mean kurtosis [MK], radial kurtosis [RK]), and NODDI (intracellular volume fraction [ICVF], orientation distribution index, isotropic water fraction [ISO]) images were obtained after preprocessing. The average value of these parameters was calculated in the solid components of the tumors. The receiver operating characteristic curve analyses were performed to investigate the diagnostic performance and the curves were compared with the Delong test. RESULTS: FA shows an increase in HGG, while MD, RD, and AD exhibit a decrease. AK, MK, and RK were higher in HGG than LGG. ICVF increased in HGG, while ISO decreased. AK demonstrated the best diagnostic performance among all parameters, and kurtosis outperformed NODDI but not DTI. Combining these parameters did not yield a statistically significant improvement in diagnostic performance. CONCLUSION: DTI, DKI, and NODDI approaches can differentiate between HGG and LGG; however, kurtosis parameters perform better and adding NODDI parameters does not improve diagnostic performance. Using multishell b-value has not led to an increase in diagnostic performance.

Simplified gyral pattern with cerebellar hypoplasia in Sedaghatian type spondylometaphyseal dysplasia: a clinical report and review of the literature.

We report on a patient with Sedaghatian type spondylometaphyseal dysplasia (SSMD) who presented with metaphyseal dysplasia, congenital atrioventricular block, simplified gyral pattern, hypogenesis of corpus callosum, and severe cerebellar hypoplasia. We want to emphasize that in this rare congenital lethal skeletal dysplasia with unknown etiology, central nervous system malformations might be a major component of the disorder and should be evaluated in detail to possibly uncover the underlying pathophysiology.

Quantitative evaluation of cortical thickness in 3T in Behçet's patients without neurological involvement and parenchymal neuro-Behçet's disease.

PURPOSE: To evaluate the spatial distribution of cortical damage in Behcet's Disease (BD) with or without neurological involvement using a cortical thickness measurement approach using three-dimensional T1-weighted imaging. MATERIAL AND METHODS: Fifty-eight BD patients without neurological involvement, twenty-two Parenchymal Neuro-Behçets disease (PNBD) patients, and fifty healthy controls were included in the prospective study. Anatomical 3D T1 images were obtained from all participants using 3T MRI. Using a computational anatomy toolbox (CAT12), we calculated and compared group differences in cortical thickness. RESULTS: Patients with BD without neurological involvement showed cortical thickness reduction in bilateral frontal, bilateral parietal, and right precuneus compared with the healthy controls (HCs) (p < 0.05 FWE corrected [FWEc]). PNBD patients showed frontoparietal cortical thickness reduction when compared with BD patients without neurological involvement (p < 0.05 FWEc). The PNBD patients showed widespread cortical thickness reduction compared with the HC patients (p < 0.05 FWEc). Disease duration was correlated with cortical thickness in the right pericalcarine (p = 0.012 false discovery rate [FDR], r = -0.40), left pericalcarine (p = 0.013 FDR, r = -0.44), and left transverse temporal (p = 0.007 FDR, r = -0.41) regions. CONCLUSION: There is a decrease in cortical thickness in BD patients without neurological involvement. Cortical thickness reduction is more prominent in parenchymal neurobehçet's patients. Cortical thickness shows a negative correlation with disease duration in some regions.