Presence of Auditory Pathway Abnormalities in Children With Neurofibromatosis Type 1 With Brainstem Focal Areas of Abnormal Signal Intensity: Diffusion Tensor Imaging Features.

Background: To investigate whether there is a difference in mean diffusivity (MD) and fractional anisotropy (FA) values in the auditory pathways of neurofibromatosis type 1 patients with and without focal areas of abnormal signal intensity (FASI) compared to healthy controls by using diffusion tensor imaging (DTI). Methods: Patients were classified as group 1 with focal areas of abnormal signal intensity in the brainstem, group 2 without focal areas of abnormal signal intensity, and healthy control group 3 according to the MRI findings. Mean diffusivity and fractional anisotropy values of lateral lemniscus, inferior colliculus, corpus geniculatum mediale, Heschl gyrus, and brainstem were compared between groups. The correlation between mean diffusivity and fractional anisotropy values of auditory pathways and age was investigated. Results: There was a significant difference between group 1 and group 2 in terms of mean diffusivity and fractional anisotropy values at lateral lemniscus, inferior colliculus, corpus geniculatum mediale, and Heschl gyrus. Increased mean diffusivity and decreased fractional anisotropy values at brainstem were found in group 1. There was a significant difference between group 1 and group 3 in terms of mean diffusivity values at all auditory pathways. Fractional anisotropy values obtained from lateral lemniscus, inferior colliculus, and Heschl gyrus decreased in group 1 compared with group 3. There was a negative correlation between mean diffusivity values and positive correlation between fractional anisotropy values at lateral lemniscus, inferior colliculus, Heschl gyrus, and age. Conclusions: Our diffusion tensor imaging findings show that the neuronal integrity of the auditory pathways is affected in neurofibromatosis type 1 patients with brainstem focal areas of abnormal signal intensity. We think that the disappearance of brainstem focal areas of abnormal signal intensity associated with myelin repair and the regression of diffusion tensor imaging changes in the auditory pathways occur simultaneously with advancing age in patients with neurofibromatosis type 1.

Long-Term Disease Course of Pontocerebellar Hypoplasia Type 10.

BACKGROUND: Pontocerebellar hypoplasia type 10 (PCH10) due to CLP1 gene mutations is characterized by structural brain anomalies, progressive microcephaly, severe intellectual and physical disabilities, and spasticity. In this follow-up study, evolution of phenotypic and neurological characteristics of patients with PCH10 is discussed. METHODS: Phenotype, growth parameters, motor functions, developmental tests, spasticity assessments, functional independence assessments, electroencephalography (EEG), and brain magnetic resonance imaging (MRI) of 10 patients with PCH10 were monitored on separate examinations. Alterations were recorded. RESULTS: Patients were followed-up for an average of 2.83 years. The tone of the upper extremities was significantly higher than that of the lower extremities, according to Modified Ashworth Scale (MAS) values. Sixty percent of patients could sit unsupported; 20% achieved supported sitting initially but lost the ability during follow-up. Absence of grabbing or sitting was observed in 20% of patients. During follow-up, one person achieved supported sitting and one person achieved head holding. Only one patient was able to speak a few words. Cerebellar atrophy (two of 10), pons hypoplasia (four of 10), cortical atrophy (seven of 10), enlarged ventricles (10 of 10), thinning of the corpus callosum (10 of 10), hypomyelination (six of 10), and increased white matter signal intensity (six of 10) were the observed MRI findings. CONCLUSIONS: Progressive cerebral and cerebellar atrophy was demonstrated radiologically for the first time in a PCH10 cohort. It is of crucial importance to identify these patients promptly with the help of dysmorphic findings and spasticity being pronounced in the upper extremities. Furthermore, we note that phenotypic and neurological examination findings tend to change slightly over time.

The relationship between nutritional status and white matter integrity in older adults: A diffusion tensor imaging study.

OBJECTIVES: The purpose of this study to determinate whether there is a relationship between the nutritional status and white matter integrity in older patients by using Diffusion Tensor Imaging (DTI). METHODS: The patients were evaluated by Mini-Nutritional Assessment Scale. The patients are categorized in the groups of well-nourished, risk of malnutrition, or malnourished, depending on the overall score> 23.5, 17-23.5, or 17; respectively. All patients had brain MRI and DTI. The mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) values were calculated by ROI-based method in white matter tracts. RESULTS: Total of the 224 patients; 86 patients had normal nutrition status (group 1), 107 patients were diagnosed with malnutrition risk (group 2) and 31 patients were diagnosed with malnutrition (group 3). Significantly decreased FA values of genu of corpus callosum, forceps minor and significantly increased MD values of middle cerebellar peduncle, and superior frontooccipital fasciculus were detected in group 2 in comparison to group 1 (p < 0.05). After adjusting for the folate and age, MD and RD values of cingulum remained significantly higher and the AD values of superior cerebellar peduncle remained significantly lower in group 3 (p < 0.05). CONCLUSIONS: Malnutrition was associated with deteriorated DTI values, especially in cingulum and superior cerebellar peduncle. Assessing the nutritional status of older individuals is crucial to avoid its negative impact on brain. ADVANCES IN KNOWLEDGE: Early diagnosis of malnutrition-related impaired WM integrity is important for prevention and intervention, and DTI is a useful non-invasive technique to be used for this purpose.

Diffusion tensor imaging findings in the hunger and satiety centers of the brain after bariatric surgery: a preliminary study.

PURPOSE: To investigate the alterations in the diffusion tensor imaging (DTI) parameters measured in the hunger and satiety centers of the brain before and after bariatric surgery (BS) in morbidly obese patients. METHODS: Fourty morbidly obese patients were evaluated before and after BS. Mean diffusivity (MD) and fractional anisotropy (FA) values were calculated from 14 related brain locations, and the DTI parameters were analyzed. RESULTS: After the BS, the mean BMI of the patients decreased from 47.53 ± 5.21 to 31.48 ± 4.21. The MD and FA values in the all of the hunger and satiety centers was found statistically significant different in the pre-surgery period compared to the post-surgery period (for each; p-value < 0.001). CONCLUSION: The FA and MD changes after BS may be attributed to reversible neuroinflammatory alterations in the hunger and satiety centers. Decreased MD and FA values after BS may be explained by the neuroplastic structural recovery in the related brain locations.

Differentiation of lung and breast cancer brain metastases: Comparison of texture analysis and deep convolutional neural networks.

PURPOSE: Metastases are the most common neoplasm in the adult brain. In order to initiate the treatment, an extensive diagnostic workup is usually required. Radiomics is a discipline aimed at transforming visual data in radiological images into reliable diagnostic information. We aimed to examine the capability of deep learning methods to classify the origin of metastatic lesions in brain MRIs and compare the deep Convolutional Neural Network (CNN) methods with image texture based features. METHODS: One hundred forty three patients with 157 metastatic brain tumors were included in the study. The statistical and texture based image features were extracted from metastatic tumors after manual segmentation process. Three powerful pre-trained CNN architectures and the texture-based features on both 2D and 3D tumor images were used to differentiate lung and breast metastases. Ten-fold cross-validation was used for evaluation. Accuracy, precision, recall, and area under curve (AUC) metrics were calculated to analyze the diagnostic performance. RESULTS: The texture-based image features on 3D volumes achieved better discrimination results than 2D image features. The overall performance of CNN architectures with 3D inputs was higher than the texture-based features. Xception architecture, with 3D volumes as input, yielded the highest accuracy (0.85) while the AUC value was 0.84. The AUC values of VGG19 and the InceptionV3 architectures were 0.82 and 0.81, respectively. CONCLUSION: CNNs achieved superior diagnostic performance in differentiating brain metastases from lung and breast malignancies than texture-based image features. Differentiation using 3D volumes as input exhibited a higher success rate than 2D sagittal images.

Evaluation of the white matter integrity in morbidly obese patients before and after bariatric surgery; a diffusion tensor imaging study.

PURPOSE: To investigate the difference in FA (Fractional anisotropy), ADC (Apparent diffusion coefficient), RD (Radial diffusivity) and AD (axial diffusivity) values of white matter (WM) tracts in morbidly obese subjects before and after bariatric surgery (BS). MATERIALS AND METHODS: A group of thirty-nine morbidly obese subjects are evaluated before and 4-6 months after BS. ADC, FA, RD and AD values of 17 distinct neuroanatomic localizations are measured and DTI parameters are analyzed. RESULTS: Following the BS, the patients' mean BMI decreased from 47.665.21 to 31.723.97. A significant difference is displayed between the pre-surgery and post-surgery FA values of SLF, SFOF, ALIC, fornix, ILF, CST, MCP (p = 0.010, p < 0.001, p = 0.048, p = 0.014, p = 0.012, p = 0.012, p = 0.040 respectively). Following BS, decrease in FA values in the mentioned areas are detected. ADC values obtained from MCP are significantly lower in the post-BS period compared to pre-BS period (p = 0.018). There was a statistically significant difference between the pre-surgery and post-surgery AD values of SLF, SFOF, ILF, ALIC, EC, CST, and MCP (p = 0.001, p = 0.022, p = 0.001, p = 0.011, p = 0.001, p = 0.000, p = 0.000, respectively). Following the BS, AD values of the SLF, SFOF, ILF, ALIC, EC, CST, and MCP are decreased. RD values measured from GCC are significantly lower in the post-BS period compared to pre-BS period (p = 0.008). CONCLUSION: Our study supported the hypothesis of the BS-induced reversibility of the low-grade inflammation in WM tracts in the morbidly obese group following BS. Our DTI results may represent the subacute period findings of the reversal of low-grade inflammation after BS.

Evaluation of white matter integrity by diffusion tensor imaging in the deficiencies of vitamin B12 and folate in older patients.

OBJECTIVES: The aim of this study is to investigate whether white matter (WM) integrity is impaired in vitamin B12 and folate deficiency with Diffusion Tensor Imaging (DTI) in older patients. METHODS: All the patients aged ≥65 years admitted to the geriatric clinic and performed DTI-MRI were included in the study. DTI parameters (fractional anisotropy, mean diffusivity, axial diffusivity, radial diffusivity) were calculated by ROI-based method in white matter tracts. Deficiency threshold for vitamin B12 were defined as <200 pg ml-1 and <400 pg ml-1 separately; and for folate as <3 ng ml-1 and <6 ng ml-1, separately. RESULTS: DTI was performed to older patients having serum vitamin B12 level (n = 106, mean age = 80.7±7.7, 66% female) and folate level (n = 101, mean age = 80.7±7.5, 67.3% female). Significantly lower FA and higher MD and RD levels were observed in multiple WM areas including superior and middle cerebellar peduncles, cingulum and genu of corpus callosum in patients with vitamin B12 <400 pg ml-1 (p < 0.05). DTI indices also showed significant changes in the genu of corpus callosum, and right and left superior longitudinal fasciculus in patients with folate <6 ng ml-1 (p < 0.05). CONCLUSIONS: Deficiencies of vitamin B12 and folate may be associated with impaired white matter integrity in elderly even at high laboratory levels, and DTI is a useful method to detect it. ADVANCES IN KNOWLEDGE: Early detection of impaired WM integrity caused by micronutrient deficiencies poses a great significance in terms of prevention and intervention, and DTI is an effective non-invasive method to be used for this purpose.

Microstructural alterations in hypoxia-related BRAIN centers after COVID-19 by using DTI: A preliminary study.

PURPOSE: To investigate whether the diffusion tensor imaging (DTI) parameters alterations in the in hypoxia-related neuroanatomical localizations in patients after COVID-19. Additionally, the relationship between DTI findings and the clinical severity of the disease is evaluated. METHODS: The patients with COVID-19 were classified into group 1 (total patients, n = 74), group 2 (outpatient, n = 46), and group 3 (inpatient, n = 28) and control (n = 52). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated from the bulbus, pons, thalamus, caudate nucleus, globus pallidum, putamen, and hippocampus. DTI parameters were compared between groups. Oxygen saturation, D dimer and lactate dehydrogenase (LDH) values associated with hypoxia were analyzed in inpatient group. Laboratory findings were correlated with ADC and FA values. RESULTS: Increased ADC values in the thalamus, bulbus and pons were found in group 1 compared to control. Increased FA values in the thalamus, bulbus, globus pallidum and putamen were detected in group 1 compared to control. The FA and ADC values obtained from putamen were higher in group 3 compared to group 2. There was a negative correlation between basal ganglia and hippocampus FA values and plasma LDH values. The ADC values obtained from caudate nucleus were positively correlated with plasma D Dimer values. CONCLUSION: ADC and FA changes may reveal hypoxia-related microstructural damage after COVID-19 infection. We speculated that the brainstem and basal ganglia can affected during the subacute period.

MRI evaluation of right heart functions in children with mild cystic fibrosis.

BACKGROUND: This study aimed to assess the ventricular anatomy, function of the right ventricle, and the haemodynamic findings of pulmonary artery in children with cystic fibrosis using cardiac MRI. PATIENTS: This prospective study consisted of 32 children with mild cystic fibrosis and 30 age-matched healthy control participants. METHODS: Cardiac MRI was used to assess right ventricular volumes, anatomy, and function and to assessment of haemodynamic findings of pulmonary artery in the control and study groups. Haemodynamic findings of pulmonary arteries were determined using pulmonary arteries peak velocity (cm/s), and pulmonary arteries time-to-peak velocity (ms) and pulmonary artery systolic pressure. All data of children with mild cystic fibrosis were compared with those of 30 age-matched healthy control group participants. RESULTS: Our patients and their age-matched controls were aged from 6 to 17 years and from 7 to 15 years, respectively. We found that ejection fraction (%), cardiac output (L/ml), cardiac output (L/ml/m2), and systolic volume (ml/m2) were significantly lower in children with cystic fibrosis (p < 0.01). Right ventricular anterior wall thickness (mm) was significantly higher in children with cystic fibrosis (p = 0.01). No significant difference was observed between the haemodynamic parameters of pulmonary artery in the patient group. CONCLUSION: In our study, cardiac MRI was used to investigate whether the right ventricle was affected functionally and anatomically in children with mild cystic fibrosis. We detected a significant decrease in right ventricular systolic functions and notable alterations in the right ventricular geometry of children with mild cystic fibrosis. These alterations usually manifest themselves as hypertrophy of the right ventricle. Our study's results demonstrate no relationship between the development of pulmonary hypertension in mild cystic fibrosis children.

MR Features of Varicella-zoster Myelitis in an Immunocompetent Patient.

BACKGROUND: Varicella-zoster virus (VZV) is a latent virus that can remain in the central nervous system. Reactivation of the virus can cause some neurologic manifestations, and myelitis is one of the rarest of them. In this report, we aimed to present the MRI features of long-segment cervical myelitis after VZV infection, which is rarely reported in the literature. CASE PRESENTATION: A 69-year-old patient, who was diagnosed with varicella-zoster two months ago and treated with valacyclovir, was admitted to our clinic with worsening of his complaints and weakness in the right upper extremity. Neurological examination was normal in the left upper and bilateral lower extremities, but the muscle strength in the right upper extremity was evaluated as 4/5 grade. While rare leukocytes (10 leukocytes/mm³, 50 erythrocytes/mm³, high protein level (46 mg/dl, ref.15- 40 mg/dl)) were seen in the cerebrospinal fluid (CSF) analysis, no microorganisms were seen, and no growth was observed in the culture. VZV antibody-immunoglobulin G (Ab-IgG) was positive in CSF, while polymerase chain reaction [PCR] for VZV was negative. On cervical MRI, lesions showing T2 hyperintensity were observed from the C3-4 level to the C7-T1 level, eccentrically located in the right paramedian spinal cord. On post-contrast images, patchy heterogeneous contrast enhancement was noted in these regions of the spinal cord. When the patient's history, CSF features and MRI examinations were evaluated together, the lesions were consistent with VZV myelitis. The patient was started on valacyclovir treatment, and during the follow-up, the patient's complaints decreased, while no progress was observed in neurologic symptoms. CONCLUSION: As a result, we aimed to report the MRI features of this rare complication of varicellazoster and emphasize the necessity of keeping this in mind in the etiology of myelitis, especially in cases with patchy enhancement, to achieve early diagnosis and treatment.

An incidental diagnosis of an unusually located echinococcus alveolaris.

ABSTRACT: Hydatid cyst disease is a zoonotic infection caused by the genus Echinococcus. Hydatid cysts are usually located in the liver or lungs whereas the brain is an unusual location. A 45-year-old male patient was diagnosed with an intracranial mass suggesting a metastasis in the frontal region shown in the cranial computed tomography (CT) scan following a cranial trauma. The histological evaluation revealed an acellular laminated lesion surrounded with reactive changes, compatible with a cuticle. These findings were evaluated in favour of a hydatid cyst caused by Echinococcus multilocularis. Alveolar echinococcosis is a zoonotic disease caused by the genus Echinococcus multilocularis. Hydatid cyst is a common public health issue in the countries where livestock farming is common. Primary or metastatic tumours and abscesses should be considered in the differential diagnosis of hydatid cysts regardless of their location.

Importance of Susceptibility-weighted-imaging in Methanol Toxicity.

Methanol poisoning is a rare but potentially lethal condition. Haemorrhagic necrosis of bilateral basal ganglia, particularly of the putamen, is one of the distinctive features of this entity. One of the proposed responsible mechanisms for putaminal haemorrhagic necrosis due to methanol toxicity is inadequate venous drainage of this region. Advanced imaging modalities are used to guide diagnosis and patient management. Here, we report a 61-year man who had a fulminant acute methanol toxicity due to accidental ingestion. Susceptibility-weighted-imaging (SWI) showed marked bilateral basal ganglia and brainstem haemorrhage. Also, congested and dilated venous structures were detected in SWI, which may be an indirect sign of inadequate venous drainage of this region. We intend to present the cerebral SWI features of a patient with fulminant methanol toxicity in order to clarify the underlying physiopathology of the brain damage, which has not yet been presented in the literature to the best of our knowledge. Key Words: Methanol, Toxic encephalopathy, Magnetic resonance imaging, Cerebral haemorrhage.

The value of adjacent vessel sign in malignant breast tumors.

PURPOSE The aim of this study was to evaluate the prognostic quality of adjacent vessel sign (AVS) in malignant breast tumors by comparing it with classical prognostic pathological biomarkers and magnetic resonance imaging (MRI) findings. METHODS A total of 124 patients with 133 malignant lesions were included. All the imaging was performed on a 1.5T Avanto scanner and the images were interpreted according to BI-RADS-MR® (fifth ed.) atlas. Maximum intensity projection (MIP) images were constructed from subtracted post-contrast images and were used to investigate AVS. Histopathological results and MRI findings were compared with AVS. RESULTS Interobserver agreement about AVS status was substantial (κ=0.64). AVS positive lesions were significantly bigger in size (P < .001, AVS negative: median 12 mm, AVS positive: median 31 mm). AVS was significantly associated with increased Ki-67 index and axillary lymph node metastasis (P=.009 and P=.019, respectively). Between AVS and lymphovascular invasion (LVI), there was a trend toward positive relationship (P=.076). MRI findings of T2 hypointensity, peritumoral edema, irregular shape, non-homogeneous contrast enhancement, rapid early contrast enhancement, and skin infiltration showed significant positive relation with AVS (P < .001, P < .001, P < .001, P=.02, P=.021, and P=.021, respectively). AVS is found to be associated with increased Ki-67 index, axillary lymph node metastasis, and some MRI findings that point to malignancy or poor prognosis. CONCLUSION AVS indicates poor prognosis since it is related to axillary lymph node metastasis, increased Ki-67 index, LVI, peritumoral edema, rapid early contrast enhancement, increased background enhancement, skin extension, T2 hypointensity, non-homogeneous contrast enhancement, irregular lesion shape, and larger tumor size. AVS is an easy to use sign that shows substantial interobserver agreement.

Evaluation of toxic effects of chemotherapy in lung malignancies on cerebral white matter using diffusion tensor imaging.

BACKGROUND: Non-small cell lung cancer (NSCLC) is a leading cause of morbidity and mortality. Carboplatin and cisplatin based regimens are used in the treatment of NSCLC. The aim of the study was to find out whether there is a difference in white matter (WM) changes between two platinum-based chemotherapy agents using diffusion tensor imaging (DTI). PATIENTS AND METHODS: 25 patients who received chemotherapy for NSCLC and 27 age-matched healthy controls were enrolled in the study. Fractional anisotropy (FA), axial diffusivity (AD), mean diffusivity (MD) and radial diffusivity (RD) values of the study population were measured from 11 regions of interest in pre-chemotherapy and post-chemotherapy MRI data. RESULTS: Cisplatin group showed a significant decrease in the FA of the inferior longitudinal fasciculus (P = 0.028). Carboplatin group showed a significant FA decrease and RD increase in the forceps minor (P = 0.022 and P = 0.011, respectively), and a significant reduction in AD and increase in MD in frontal white matter (WM) (P = 0.008 and P = 0.029, respectively). In comparison of post chemotherapy DTI values of the two groups, carboplatin group showed lower FA, and higher MD and RD values than cisplatin group in parieto-occipital WM (P = 0.034, P = 0.034, P = 0.029, respectively). CONCLUSIONS: The findings of the study suggest that subtle effects of chemotherapy detectable with DTI may emerge after the treatment. In addition, carboplatin regimen may have more impact on WM than cisplatin regimen.

Dynamic Contrast-Enhanced MR Perfusion in Differentiation of Benign and Malignant Brain Lesions.

BACKGROUND: We aimed to differentiate Glioblastoma Multiforme (GBM) from benign lesions like Developmental Venous Anomaly (DVA) and Cavernous Malformation (CM) by Dynamic Contrast-Enhanced MR Perfusion (DCE-MRP) markers such as Ktrans, Ve, Kep, and IAUC. METHODS: We retrospectively evaluated 20 patients; 10 GBM as the malignant group, 5 CM and 5 DVA as the benign group. Ktrans, Kep, Ve, and IAUC parameters were measured by DCE-MRP, within the lesion, at perilesional nonenhancing white matter (PLWM) and contralateral normal appearing white matter (CLWM). RESULTS: All benign and malignant lesions exhibited significantly increased Ktrans, Ve, and IAUC values compared to PLWM and CLWM (p < 0.001, p=0.006 and p<0.001). Subtracted Kep values between lesion and PLWM were significantly different between the benign and malignant groups, as the malignant group exhibited higher subtracted Kep values (p 0.035). For the malignant group; Ktrans and IAUC values at the lesion were positively correlated (r 0.911), while Kep and Ve at CLWM were negatively and strongly correlated (r 0.798). For the benign group; Ktrans with Ve and Ktrans with IAUC at lesion (r 0.708 and r 0.816 respectively), Ktrans and IAUC at PLWM (r 0.809), Ktrans and IAUC at CLWM(r 0.798) were strongly and positively correlated. Ktrans, Ve, and IAUC values can be used to restrict the lesion in both groups. CONCLUSION: Ktrans strongly correlates with IAUC and they can be used instead of each other in both benign and malignant lesions. Classical DCE-MRP parameters cannot be used in the differentiation of malignant lesions from benign vascular lesions. However, subtracted Kep values can be used to differentiate GBM from benign vascular lesions.

Clinical and molecular findings in 6 Turkish cases with Krabbe disease.

BACKGROUND: Krabbe disease is a rare lysosomal storage disorder with a neurodegenerative course that occurs because of the deficiency of the beta-galactocerebrosidase (GALC) enzyme activity. The genetic basis of Krabbe disease consists of biallelic mutations in the GALC gene, but the genetic spectrum in the Turkish population is poorly defined. We aimed to present a Turkish case-series with infantile-onset Krabbe disease, define the clinical and molecular findings and compare the genetic spectrum with the mutations previously reported in the literature. METHODS: Six cases, who were referred to our clinic between 2015-2019, with a definite diagnosis of infantileonset Krabbe disease were included in the study. The family history, clinical information, biochemical and radiological examinations of the patients were screened and evaluated. All encoded exons and exon-intron regions of the GALC gene were sequenced using next generation sequencing technology. Multiplex ligationdependent probe amplification analysis was used for deletion type mutations that could not be detected by sequence analysis. RESULTS: GALC gene sequence analysis revealed four known mutations including c.1394C > T (p.Thr465Ile), c.411_413delTAA (p.Lys139del), c.820G > C (p.Glu274Gln), and 30 kilobase deletion mutation among the exons 11-17 (IVS10del30kbp). Moreover, the c.1623G > A (p.Trp541Ter) variant, which was not previously reported in the literature, was detected in two cases. CONCLUSIONS: We believe that the demonstration of the genetic spectrum of infantile-onset Krabbe disease in Turkish patients will be an important contribution to the GALC mutation data in our country. More importantly, two novel variants were defined. This knowledge may enable early detection and treatment with the advent of a carrier or newborn screening tests.

Cognitive and brain micro-structural correlates of alexithymia in essential tremor patients.

Essential tremor (ET) is the most common movement disorder which has both motor and non-motor findings such as neuropsychiatic symptoms. Alexithymia is defined as inability to identify and describe emotions experienced by one's self or others. In our study, we aimed to evaluate the neurocognitive and brain micro-structural correlates of alexithymia in ET. 40 ET patients (mean age = 53.05 ± 19.74 years), were included. Fahn-Tolosa-Marin Tremor Rating Scale, Toronto Alexithymia Scale (TAS), Beck Depression Inventory, Beck Anxiety Inventory and detailed neurocognitive evaluation were applied to all patients. The patients were divided into three groups based on their TAS scores: no alexithymia, probable alexithymia, definite alexithymia. Diffusion Tensor Imaging (DTI) was performed in all patients. The mean TAS score was 50.05 ± 10.06. Depressive symptoms and anxiety levels were higher in definite alexithymia (p < 0.001, p < 0.01). Partial correlation controlling for age, gender and educational level between alexithymia scores and each cognitive test showed significant association between similarities (p < 0.001) and phonemic verbal fluency (p = 0.04). Left orbitofrontal cortex average diffusion coefficient (ADC) value (p = 0.05), left anterior cingulate cortex fractional anisotropy (FA) value (p = 0.04), right cuneus FA value (p = 0.04), left amygdala ADC value (p = 0.01) and left insula ADC value (p = 0.02) were differed between groups. TAS and DTImetrics were not found to be independently associated with the level of anxiety (p < 0.001) and depressive symptoms (p < 0.01). As a conclusion, impairments in executive function and complex attention were correlated with higher levels of alexithymia in ET. Many micro-structural alterations were determined to be correlated with alexithymia levels.

Relationship of diffusion tensor imaging parameters with neurocognitive dysfunction in patients with Behcet's disease.

Behcet's disease (BD) is a chronic, multisystemic, relapsing-remitting, progressive inflammatory disorder with unknown etiology. The aim of the study is to investigate the white matter integrity and subclinical brain parenchymal involvement in Behcet's subjects by utilizing diffusion tensor imaging (DTI) and to correlate apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) values measured from the diverse distinct anatomic locations with the disease duration time and neurocognitive function test results. Thirty-five adults with Behcet's disease and 21 age-matched healthy controls were enrolled in this study. Neurocognitive functions of the patients were evaluated with the Brief Repetable Battery-Neuropsychological tests (BRB-N). In both groups, DTI metrics were calculated from 19 different locations in the brain. The association between the DTI parameters and disease duration time and neurocognitive function test results were investigated. In Behcet's disease, at the cingulum and the splenium of the corpus callosum (SCC), FA values were significantly lower compared with the controls (p = 0.0015, p = 0.003, respectively). The ADC values of the corona radiata and RD values of superior longitudinal fasciculus and SCC were significantly higher than the controls (p = 0.023, p = 0.028, p = 0.006, respectively). Significant negative correlations were found between the FA values of cingulum, genu of corpus callosum (GCC), posterior limb of internal capsule (PLIC) and disease duration time (r = - 0.368; p = 0.029 and r = - 0.337; p = 0.048 and r = - 0.527; p = 0.001 respectively). All BD subjects performed significantly lower test scores on the spatial recall test (SPART) (p = 0.001). In addition, negative correlation was found between the MD values of the parietooccipital white matter and the selective reminding test (SRT) results (r = - 0.353; p = 0.037). Our DTI study presented microstructural alterations in the neurocognitive-related areas and BRB-N test results even in patients without neurological symptoms which may imply insidious neurological involvement.