Search

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.

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.

Rationale and Objectives We aimed to investigate whether there are any differences in apparent diffusion coefficient (ADC) values obtained from liver metastases due to gastroenteropancreatic neuroendocrine tumors (GEP-NET) and adenocarcinomas. Materials and Methods We included 54 patients with 167 liver metastases due to gastroenteropancreatic tumors. We divided the patients into two groups as liver metastases due to GEP-NETs (seven patients with 51 lesions, mean age: 48) and adenocarcinomas (47 patients with 116 lesions, mean age: 61.2). We used the independent samples t-test to compare the ADC and ADCmean values of the two groups and performed a receiver-operating characteristic analysis. Results ADC and ADCmean values were significantly lower in the GEP-NET group compared with the adenocarcinoma group. Receiver-operating characteristic curve analysis showed a significant difference for ADC and ADCmean values, and area under the curve values were 0.733 and 0.790, respectively. The cut-off values were 933x10-6 mm2/s for ADC and 801x10-6 mm2/s for ADCmean. Diagnostic accuracies of ADC (Sensitivity = 80.2, Specificity = 64.7, PPV = 83.8, NPV = 58.9) and ADCmean (Sensitivity = 63.8, Specificity = 82.4, PPV = 89.2, NPV = 50) were calculated in differentiating adenocarcinoma metastases from GEP-NET metastases. Conclusion The lower ADC and ADCmean values of liver metastases suggest GEP-NET rather than adenocarcinomas. ADC and ADCmean values obtained from liver metastases may be used to differentiate NETs from adenocarcinomas.

Background: The effectiveness of Diffusion Tensor Imaging (DTI) in demonstrating functional changes in the tumor in determining the response to treatment after radiosurgery in patients with vestibular schwannoma (VS) is not clear yet. Objective: The study aimed to determine the change total in tumor volume (TTV) in terms of radiological response in patients who had VS and were treated with radiosurgery and investigate the relationship between the TTV, follow-up times and DTI parameters. Methods: Thirty-one patients were assessed using DTI and MRI. TTV, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were calculated. Patients were divided into tree groups: those who responded to the treatment (group 1) (n=11), who did not (group 0) (n=9) and who remained stable (group 2) (n=11). Background: The effectiveness of Diffusion Tensor Imaging (DTI) in demonstrating functional changes in the tumor in determining the response to treatment after radiosurgery in patients with vestibular schwannoma (VS) is not clear yet. Objective: The study aimed to determine the change total in tumor volume (TTV) in terms of radiological response in patients who had VS and were treated with radiosurgery and investigate the relationship between the TTV, follow-up times and DTI parameters. Methods: Thirty-one patients were assessed using DTI and MRI. TTV, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were calculated. Patients were divided into tree groups: those who responded to the treatment (group 1) (n=11), who did not (group 0) (n=9) and who remained stable (group 2) (n=11). Results: The mean duration of follow-up was 28.81±14 months. ADC values increased in patients with VS after radiosurgery (p=0.004). There was no statistical difference in the FA values. A significant reduction in TTV after radiosurgery was detected in group 1 (p=0.003). ADC values increased significantly after radiosurgery in group 2 (p=0.04). Although there were no significant differences, ADC values after radiosurgery increased in group 1 and group 0. Conclusions: ADC values continuously increase due to radiation damage in the period before the tumor volume shrinks after radiosurgery. We think that it is not appropriate to diagnose inadequate treatment or progression only when TTV is evaluated in terms of response to treatment in the early period after radiosurgery.

To investigate changes in DTI (Diffusion Tensor Imaging) parameters in brainstem subcortical auditory pathways after Gamma Knife Radiosurgery (GKR) in patients with intracanalicular vestibular schwannoma (ICVS) and to analyze the relationship between tumor volume and ADC (apparent diffusion coefficient) and FA (fractional anisotropy) values.Seventeen patients with ICVS were evaluated before and after GKR. ADC and FA values of the lateral lemniscus (LL) and inferior colliculus (IC) and tumor volume were calculated. Patients who responded to GKR were classified as Group 1 and those who did not respond adequately as Group 2. The relationship between ADC and FA values and changes in tumor volume were analyzed.Tumor volume significantly decreased after GKR. ADC values obtained from the tumor increased after GKR (p:0.002). There was no significant difference in LL and IC before and after GKR in terms of FA and ADC values (n:17). There was a positive correlation between response to treatment and contralateral LL ADC values after GKR (p=0.005, r:0.652). There was a negative correlation between contralateral IC FA values after GKR and response to treatment (p=0.017, r: -0.568). There was a significant difference between Groups 1 and 2 in regards to contralateral LL ADC (p=0.03) and IC FA values (p=0.017).Since the cochlear nerve and subcortical auditory pathways have low regeneration potential after nerve damage, ADC and FA changes in LL and IC may be explained with the presence of intracanalicular tumors prior to GKR. Since GKR does not cause additional damage to the subcortical auditory pathways at the brainstem level, we think that GKR is a noninvasive treatment method that can be used safely in patients with ICVS.İntrakanaliküler vestibüler schwannomlu (ICVS) olgularda Gamma Knife Radyocerrahisi (GKR) sonrası beyin sapı subkortikal işitsel yollarda DTG (Difüzyon Tensör Görüntüleme) parametrelerinde değişiklik olup olmadığını araştırmak ve tümör hacmi ile ADC (görünür difüzyon katsayısı) ve FA (görünür difüzyon katsayısı) değerleri arasındaki ilişkiyi analiz etmek.ICVS’li 17 hasta radyocerrahi öncesi ve sonrası değerlendirildi. Lateral lemniscus (LL) ve inferior kollikulus (IC) ADC ve FA değerleri ve tümör hacmi hesaplandı. Radyocerrahi tedavisine yanıt verenler Grup 1, yeterli yanıt vermeyenler ise Grup 2 olarak sınıflandırıldı. ADC ve FA değerleri ile tümor hacim değişiklikleri arasındaki ilişki analiz edildi.Radyocerrahi sonrası tümör hacmi belirgin azalmıştı. GKR sonrası tümörden elde edilen ADC de-ğerleri arttı (p:0,002). GKR öncesi ve sonrası LL ve IC’de FA ve ADC değerleri (n:17) açısından anlamlı farklılık saptanmadı. Tedaviye yanıt ile GKR sonrası kontralateral LL ADC değerleri arasında pozitif korelasyon mevcuttu (p=0,005, r:0,652). GKR sonrası kontralateral IC FA değerleri ile tedaviye yanıt arasında negatif korelasyon saptandı (p=0,017, r:-0,568). Grup 1 ile Grup 2 arasında kontralateral LL ADC (p=0,03) ve IC FA değerleri (p=0,017) açısından anlamlı fark vardı.Kohlear sinir ve subkortikal işitme yolakların düşük rejenerasyon potansiyeli sahip olması nedeniyle LL ve IC’deki ADC ve FA değişiklikleri mevcut olan intrakanaliküler tümör varlığı ile açıklanabilir. Radyocerrahi, beyin sapı düzeyinde subkortikal işitme yollarına ek hasar vermediğinden dolayı GKR’nin ICVS’li hastalarda güvenle kullanılabilecek noninvaziv bir tedavi yöntemi olduğunu düşünüyoruz.

Background/aim The evolving understanding of essential tremors (ET) has led to a new definition of neurodegenerative disease, pointing to diffuse brain network involvement with a wide spectrum of associated motor and nonmotor symptoms. Considering the fact that white matter should also be affected by the nature of the disease, our study aimed to evaluate the integrity of white matter and its clinical correlations in ET patients. Materials and methods Approximately 40 patients diagnosed with ET and 40 age-and sex-matched control subjects (ranging between 18–80 years old) were included in the study. The sociodemographic characteristics and clinical features of the patients were recorded. Tremors were assessed using the Fahn-Tolosa-Marin Tremor Rating Scale (FTM-TRS). Diffusion Tensor Imaging (DTI) was performed to evaluate the integrity of white matter. The selected white matter regions used for DTI assessment were the corpus callosum (CC) (i.e., the largest commissural tract in the human brain), the superior longitudinal fasciculus (SLF), and the inferior longitudinal fasciculus (ILF) (i.e., the largest association fiber bundles). Results The mean age of the ET patients and control subjects was 44.23 ± 18.91 and 37.45 ± 10.95 years old (P = 0.542). The fractional anisotropy (FA) values of the CC body (P = 0.003), ILF (p = 0.016), average diffusion coefficient (ADC) values of the CC body (p = 0.001), genu (P = 0.049), SLF (V < 0.001), and ILF (P < 0.001) differed between groups. After controlling for age and sex, there was no correlation between tremor severity and DTI parameters, but impaired integrity in the genu of CC FA (P = 0.035, r = 0.442) and the splenium of CC ADC (P = 0.007, r = 0.543) were related with a longer duration of tremor. Finally, positive family history was correlated with the splenium of CC FA and ADC (P = 0.008, r = 0.536; P = 0.027, r = 0.461) and ILF ADC (P = 0.011, r = –0.519). Conclusion In our study, major white matter structure changes were found in the ET patients. The results suggest that possible neurodegeneration also affects white matter structures in ET patients and that the duration of the tremor and family history are related with impaired integrity of white matter.

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. Method: 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). Result: 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 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.

Background: The central nervous system’s involvement in Rheumatoid Arthritis (RA) is infrequent and can be life-threatening. Mass-like CNS involvement is an unusual presentation. A 45 year old man had suffered seropositive rheumatoid arthritis for five years referred to our hospital with one-week history of right-sided facial paralysis, left hemiparesis and headache. Discussion: MRI demonstrated hyperintense mass-like lesion extended from mesencephalon to right hippocampus and basal ganglia on T2 and FLAIR images. On DWI, restricted diffusion was not present. After contrast administration, minimal contrast enhancement was noted. After methotrexate and steroid treatment, the size had been markedly shrunken on the follow-up images. The clinical symptoms were also improved. Conclusion: To our knowledge, the mass-like presentation was not reported in the literature. We report an unusual case of brain involvement of rheumatoid arthritis mimicked tumor

Purpose The aim of this study was to investigate correlations between clinical symptoms, cerebrospinal fluid flow metrics, hydrocephalus index, small-vessel disease, and white matter (WM) changes in normal pressure hydrocephalus (NPH). Methods Aquaductal stroke volumes (ASVs), Z Evans index, Fazekas grading (FG), and diffusion tensor imaging measurements from WM bundles of 37 patients with NPH were retrospectively evaluated. Mann-Whitney U test between clinical symptoms and other variables and Spearman ρ correlations for relationships between variables and Kruskal-Wallis to correlate FG with nonclinical variables were used. Results Patients with NPH had increased ASV (median 53 μL). No correlation was found between Z Evans index and ASV. Three groups of patients with dementia or ataxia or incontinence had increased ASV values than their counterparts without symptoms (55 vs 48.5 μL, 75 vs 47 μL, 64 vs 49.5 μL, respectively). Patients having 2 common symptoms of dementia and ataxia and patients having all 3 symptoms of dementia, ataxia, and incontinence were compared with ASV values of 63.5 versus 78 μL, respectively. Patients with FG 1 had median ASV values of 45 μL; FG 2, 82.5 μL; and FG 3, 59 μL. Patients with dementia had significantly higher apparent diffusion coefficient (ADC) values of corona radiata (CR) on both sides. There were no significant WM changes in patients with ataxia and incontinence. The Z Evans index was positively correlated with ADC values of CR on both sides and genu of corpus callosum. Fazekas grading was found positively correlated with ADC and negatively correlated with FA values of CR. Conclusions Patients with NPH, regardless of stages of the diseases, have increased ASV values and could benefit from shunting. Decreasing ASV values of patients with FG 3 comparing with those with FG 2 support the hypothesis of decreasing compliance of brain with aging and increasing severity of small-vessel disease.

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.

Purpose: Histopathological differentiation of primary lung cancer is clinically important. We aimed to investigate whether diffusion tensor imaging (DTI) parameters of metastatic brain lesions could predict the histopathological types of the primary lung cancer. Methods: In total, 53 patients with 98 solid metastatic brain lesions of lung cancer were included. Lung tumors were subgrouped as non-small cell carcinoma (NSCLC) (n = 34) and small cell carcinoma (SCLC) (n = 19). Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) values were calculated from solid enhanced part of the brain metastases. The association between FA and ADC values and histopathological subtype of the primary tumor was investigated. Results: The mean ADC and FA values obtained from the solid part of the brain metastases of SCLC were significantly lower than the NSCLC metastases (P < 0.001 and P = 0.003, respectively). ROC curve analysis showed diagnostic performance for mean ADC values (AUC=0.889, P = < 0.001) and FA values (AUC = 0.677, P = 0.002). Cut-off value of > 0.909 × 10-3 mm2/s for mean ADC (Sensitivity = 80.3, Specificity = 83.8, PPV = 89.1, NPV = 72.1) and > 0.139 for FA values (Sensitivity = 80.3, Specificity = 54.1, PPV = 74.2, NPV= 62.5) revealed in differentiating NSCLC from NSCLC. Conclusion: DTI parameters of brain metastasis can discriminate SCLC and NSCLC. ADC and FA values of metastatic brain lesions due to the lung cancer may be an important tool to differentiate histopathological subgroups. DTI may guide clinicians for the management of intracranial metastatic lesions of lung cancer.

Essential tremor (ET) is a complex, neurodegenerative disorder that includes motor and non-motor symptoms. There is growing interest in its non-motor features, including sleep disturbances (SD). There are no studies evaluating the brain structural correlates of SD in ET. We aimed to identify brain microstructural changes related to SD in ET. SD was evaluated using the Pittsburg sleep quality index (PSQI). Diffusion tensor imaging (DTI), with reported measures being fractional anisotropy (FA) and apparent diffusion coefficient (ADC), was used to evaluate microstructural brain changes. DTI data were compared in ET patients with vs. without SD. The mean age of 40 ET patients was 49.20 +/- 21.06 years. The mean PSQI score was 6.13 +/- 3.99, and 18 (45.0%) patients had SD. The mean PSQI score of patients with vs. without SD was 9.78 +/- 2.98 vs. 3.14 +/- 1.28 (p < 0.001). Patients with vs. without SD differed significantly with respect to several DTI findings: right (R) superior cerebellar peduncle ADC (p = 0.04), left (L) dorsolateral prefrontal cortex FA (p < 0.01), L frontooccipital fasciculus FA (p = 0.02), R posterior corona radiata (RPCR) FA (p = 0.01), L posterior corona radiata FA (p = 0.04), R posterior thalamic radiation (RPTR) FA (p = 0.02), and fornix FA (p = 0.03) Significant correlations between PSQI scores and RPCR FA (r = - 0.50, p = 0.02) and RPTR FA (r = - 0.67, p = 0.001) were also observed. Our findings suggest that certain brain changes may be associated with the clinical expression of SD in ET. These changes are discussed in terms of their possible neuroanatomical and physiological significance.

To search for CSF dynamics of idiopathic intracranial hypertension (IIH) and communicating hydrocephalus and any correlation between MRI findings, CSF metrics and CSF opening pressure in IIH. Healthy subjects (30) and subjects with IIH (29) and high-pressure communicating hydrocephalus (43) were enrolled. Nonparametric Kruskal–Wallis test (p = 0.05) was used to compare three groups, Mann–Whitney U test with Bonferroni correction to compare two groups (p = 0.016). Correlation of MRI findings of IIH with CSF metrics and CSF opening pressure was analyzed by Spearman’s Rank correlation coefficient (p = 0.05). In IIH, no correlation between MRI findings and aqueductal stroke volume (ASV) but statistically significantly CSF opening pressure in the presence of transverse sinus compression was noted. Comparing with healthy subjects, ASV was nonsignificantly lower and standardized diastolic and sum and difference of systolic and diastolic flow durations were statistically significantly lower. Comparing with hydrocephalus, the width of prepontine cistern (PPC)/the width of aqueductus sylvii (AS) was significantly higher and other CSF metrics with standardized systolic and sum of systolic and diastolic flow durations were significantly lower. In hydrocephalus, ASV and peak velocities were significantly higher. Compared with normal group, PPC/AS and reverse/forward flow duration were significantly lower and other CSF metrics were significantly higher. In hydrocephalus, significant increase in ASV and peak velocities were noted. In IIH, CSF opening pressure was statistically significantly high in the presence of transverse sinus compression and standardized diastolic flow durations were statistically significantly short that are probably effects of increased impedance of CSF flow against increased intracranial pressure and unchanged or even decreased intraventricular CSF volume.

Objective In this study, we aimed to investigate whether there is any change in diffusion tensor imaging (DTI) parameters in ipsilateral and contralateral auditory pathways after Gamma Knife radiosurgery (GKR) in patients with vestibular schwannoma (VS) and the relationship between radiosurgery variables. Methods Sixty-six patients were evaluated with MRI and DTI before and after GKR. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured from the bilateral lateral lemniscus (LL), inferior colliculus (IC), medial geniculate body (MGB), and Heschl's gyrus (HG). Results There was no significant difference in ADC and FA values obtained from bilateral LL, IC, and MGB before and after radiosurgery. However, there was a significant difference between pretreatment and post-radiosurgery contralateral HG ADC values. The ADC values obtained from the contralateral HG and IC positively correlated with the duration after radiosurgery. As the duration after radiosurgery increases, the difference between the ADC values obtained from ipsilateral and contralateral HG also increases. Conclusion The high ADC values in the contralateral HG after radiosurgery may indicate microstructural alterations such as demyelination and axonal loss. Radiation exposure doses to the brainstem and cochlea are the most important factors that can cause microstructural damage to the auditory pathways. When planning radiosurgery, extreme care should be taken to prevent the harmful effects of radiation on the auditory pathways.

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.

Background: Although epilepsy is primarily known as a cortical disorder, there is growing body of research demonstrating white matter alterations in patients with epilepsy. Objective: To investigate the prevalence of white matter hyperintensities (WMH) and its association with seizure characteristics in patients with epilepsy. Methods: The prevalence of WMH in 94 patients with epilepsy and 41 healthy controls were compared. Within the patient sample, the relationship between the presence of WMH and type of epilepsy, frequency of seizures, duration of disease and the number of antiepileptic medications were investigated. Results: The mean age and sex were not different between patients and healthy controls (p>0.2). WMH was present in 27.7% of patients and in 14.6% of healthy controls. Diagnosis of epilepsy was independently associated with the presence of WMH (ß=3.09, 95%CI 1.06-9.0, p=0.039). Patients with focal epilepsy had higher prevalence of WMH (35.5%) than patients with generalized epilepsy (14.7%). The presence of WMH was associated with older age but not with seizure characteristics. Conclusions: WMH is more common in patients with focal epilepsy than healthy controls. The presence of WMH is associated with older age, but not with seizure characteristics.

Background: Neurosarcoidosis manifests symptomatically in 5% of patients with sarcoidosis and diagnosis can be challenging if not clinically suspected. Cerebral mass-like presentation of neurosarcoidosis rarely reported in the literature. We presented a woman with neurosarcoidosis who had a cerebral mass-like lesion which completely disappeared after medical treatment. Discussion: A 37-year-old woman with history of pulmonary sarcoidosis referred to the emergency service of our hospital with a one-month history of progressive dizziness, nausea and seeing flashing lights. At neurologic examination, numbness and weakness on the left side of the body, deviation of uvula toward the right side was seen. Cranial MRI demonstrated a 2.5x2 cm in size mass lesion which hypointense on T1 WI, heterogeneous hyperintense on T2 and FLAIR sequence with peripheral vasogenic edema and heterogeneous, irregular contrast enhancement simulating brain tumor. Also, leptomeningeal and nodular contrast enhancement was seen on brainstem, cerebellar vermis, perimesencephalic cistern and left frontal, bilateral parietooccipital sulcus. In laboratory tests; The level of serum angiotensin-converting enzyme (ACE) was 53 IU/mL (N:8-52 IU/mL) and cerebrospinal fluid (CSF) ACE was 23 IU/mL (N:0-2.6 IU/mL). CSF cytology analysis was normal. Pattern 2 oligoclonal bands were present. With these clinical, laboratory and radiological findings, cerebral involvement of sarcoidosis was suspected. Biopsy was not performed due to the high risk of morbidity caused by the deep location of the lesion.Patient was treated with methylprednisolone and Azathioprine for a month.On post-treatment control imaging; lesion disappeared completely without residual leptomeningeal and nodular contrast enhancement.Also, neurologic symptoms were decreased remarkably. Conclusion: Multi-system inflammatory disorders like sarcoidosis, can present with mass-like lesion in the brain parenchyma. While early diagnosis is important to prevent unnecessary interventions like biopsy and surgery, it is crucial to initiate the necessary treatment with the aim of recovery without sequelae. Radiological and clinical follow-up are fundamental in differential diagnosis.

Background: The importance of pre-treatment Diffusion Tensor Imaging (DTI) parameters in determining the response to treatment after radiosurgery in patients with meningioma has not yet been clearly revealed. Objective: This study was conducted to determine tumor volume changes in terms of radiological response in patients with meningioma treated with Gamma Knife Radiosurgery (GKR) and to analyze the relationship between Total Tumor Volume (TTV) and Diffusion Tensor Imaging (DTI) parameters. In addition, we investigated whether the response to treatment can be predicted by pre-radiosurgery DTI findings. Methods: Fifty-four patients were assessed using MRI and DTI before and after GKR. Mean Diffusivity (MD), Fractional Anisotropy (FA), Radial Diffusivity (RD), and TTV of tumour were determined. Patients with 10% or more decrease in TTV after GKR were classified as group 1 and those with less than 10% decrease in volume or increase in volume were considered group 2. The relationships between MD, RD, and FA values and TTV were investigated. Results: A decrease of 46.34% in TTV was detected in group 1 after GKR, while TTV increased by 42.91% in group 2. The lowest pre-treatment FA value was detected in group 1. In addition, after GKR, FA values showed a significant increase in group 1. MD and RD values increased in both groups after radiosurgery. There was a negative correlation between pre-treatment FA, RD, and MD values after radiosurgery. Conclusions: Detection of low FA values due to the poor fiber content in meningioma before radiosurgery may be a guide in predicting the response to treatment. Further studies are required to have a better understanding of the relationship between pre- and post-treatment follow-up FA values and tumor volume in determining the efficacy of GKR in patients with meningioma.

Objectives: The purpose of the study was to determine DTI properties of brain metastases in subjects with Non-Small Cell Lung Carcinoma (NSCLC) to evaluate whether there was a correlation between DTI findings and Programmed Cell Death Ligand-1 (PD-L1). Methods: The study population (n:22) was assigned to PD-L1 negative (Group 1: PD-L1 expression Results: The mean ADC values were lower in group 2 compared to group 1. The peritumoral ADC values were higher in group 2 compared to group 1. Mean peritumoral edema FA values were lower in group 2 compared to group 1. The peritumoral edema nADC values were higher in group 2 compared to group 1. As PD-L1 expression frequency increased, ADC values in the peritumoral edema area increased and FA values decreased. Conclusions: We thought that the existence of PD-L1 protein does not affect ADC and FA values of brain metastasis (BM) originating from NSCLC. DTI characteristics of the peritumoral edema area could be a guide in determining the PD-L1 protein status of brain metastases of NSCLC. The relationship between PD-L1 expression status and DTI features in BM from NSCLC could help us to have an idea regarding the response to immunotherapy.

Background Death is the most serious complication of intracerebral hemorrhage. Microbleeding can be a precursor of intracerebral hemorrhage. Susceptibility weighted imaging (SWI) should be included in imaging protocols for some specific groups such diabetic hemodialysis patients in terms of prediction of macrohemorrhages. Purpose To investigate intracerebral microbleeding in hemodialysis patients and the correlation between microbleeding and neurocognitive impairment. Material and Methods Forty-nine hemodialysis cases were involved in the study. Locations of microbleeding, correlation between microbleeding and hypertension, diabetes mellitus (DM), age, and duration of dialysis were analyzed. Standardized mini-mental test was performed. The tested cases were divided into two groups: intracerebral microbleeding (group 1, n = 26) and without intracerebral microbleeding (group 2, n = 17). Results Incidence of microbleeding and macrohemorrhage was noted as 59% and 14%, respectively, in all cases. All macrohemorrhagic cases also have microbleeding. In group 1, neurocognitive impairment was detected in 10 (38.4%) cases: six and four cases with moderate and mild impairment, respectively. In group 2, neurocognitive impairment was detected in 2 (11.7%) cases, both with mild impairment. A significant positive correlation was detected between microbleeding and neurocognitive impairment ( P = 0.031). Although there was no correlation between attention disorder and microbleeding, a positive correlation was detected between close memory impairment and microbleeding ( P = 0.027). A positive correlation was detected between DM and microbleeding ( P = 0.027). Conclusion In hemodialysis patients, microbleeding can be a cause of neurocognitive impairment which will be important for guide to treatment protocols. SWI should be included in the imaging protocol of diabetic hemodialysis patients with neurocognitive deterioration.

Background and Purpose: Recent studies have shown that diffusion tensor imaging (DTI) parameters are used to follow the patients with breast cancer and correlate well as a prognostic parameter of breast cancer. However, as far as we know, there is no data to compare the DTI features of breast cancer brain metastases according to molecular subtypes in the literature. Our aim is to evaluate whether there are any differences in DTI parameters of brain metastases in patients with breast cancer according to molecular subtypes. Methods: Twenty-seven patients with breast cancer and 82 metastatic brain lesions were included. We classified subjects into three subgroups according to their hormone expression; Group 0, triple- negative (n; 6, 19 lesions), group 1, HER2-positive (n;16, 54 lesions) and group 2, hormone-- positive group (n; 5, 9 lesions). The apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values in DTI were measured and compared between three groups. Results: ADC, AD and RD values of group 2 were significantly lower compared to group 0. No significant differences were found in FA, ADC, AD and RD values between the group 0 and 1 and the group 1 and 2. Conclusion: Metastasis of aggressive triple-negative breast cancer showed higher ADC values compared to the less aggressive hormone-positive group. Higher ADC values in brain metastases of breast cancer may indicate a poor prognosis, so DTI findings could play a role in planning appropriate treatment.

Background/aim The evolving understanding of essential tremors (ET) has led to a new definition of neurodegenerative disease, pointing to diffuse brain network involvement with a wide spectrum of associated motor and nonmotor symptoms. Considering the fact that white matter should also be affected by the nature of the disease, our study aimed to evaluate the integrity of white matter and its clinical correlations in ET patients. Materials and methods Approximately 40 patients diagnosed with ET and 40 age-and sex-matched control subjects (ranging between 18–80 years old) were included in the study. The sociodemographic characteristics and clinical features of the patients were recorded. Tremors were assessed using the Fahn-Tolosa-Marin Tremor Rating Scale (FTM-TRS). Diffusion Tensor Imaging (DTI) was performed to evaluate the integrity of white matter. The selected white matter regions used for DTI assessment were the corpus callosum (CC) (i.e., the largest commissural tract in the human brain), the superior longitudinal fasciculus (SLF), and the inferior longitudinal fasciculus (ILF) (i.e., the largest association fiber bundles). Results The mean age of the ET patients and control subjects was 44.23 ± 18.91 and 37.45 ± 10.95 years old (P = 0.542). The fractional anisotropy (FA) values of the CC body (P = 0.003), ILF (p = 0.016), average diffusion coefficient (ADC) values of the CC body (p = 0.001), genu (P = 0.049), SLF (V < 0.001), and ILF (P < 0.001) differed between groups. After controlling for age and sex, there was no correlation between tremor severity and DTI parameters, but impaired integrity in the genu of CC FA (P = 0.035, r = 0.442) and the splenium of CC ADC (P = 0.007, r = 0.543) were related with a longer duration of tremor. Finally, positive family history was correlated with the splenium of CC FA and ADC (P = 0.008, r = 0.536; P = 0.027, r = 0.461) and ILF ADC (P = 0.011, r = –0.519). Conclusion In our study, major white matter structure changes were found in the ET patients. The results suggest that possible neurodegeneration also affects white matter structures in ET patients and that the duration of the tremor and family history are related with impaired integrity of white matter.

Background Essential tremor (ET) is disease with both motor and non-motor features. Notable among the non-motor features is cognitive impairment. While this impairment has been attributed to cortico-thalamo-cerebellar pathway pathology, it is likely that a more complicated involvement of brain structures underlies cognitive function in ET. Objective To evaluate the brain microstructural changes of both white matter and grey matter in ET using region of interest based diffusion tensor imaging (DTI), and to correlate these changes with cognitive function assessed during detailed neuropsychological testing. Method Thirty-five non-demented ET patients with a range of cognitive function (Clinical Dementia Rating = 0-0.5, mean age = 57.5 ± 16.7 years, age range = 23-76 years) underwent a comprehensive neuropsychological evaluation and brain magnetic resonance imaging, including DTI. DTI findings were reported as fractional anisotropy, average diffusion coefficient, these values were evaluated for 32 ROIs. Cognitive domains included attention, visuospatial functions, executive function, verbal memory, visual memory, and language. Domain Z-scores were calculated each cognitive domain and compared for each brain region. Results Microstructural changes in prefrontal cortical areas (dorsolateral, ventrolateral), paralimbic and limbic structures (posterior cingulate cortex, precuneus, hippocampus), basal ganglia (substantia nigra, putamen, caudate nucleus) and white matter bundles (corpus callosum, anterior thalamic radiation, longitudinal fasciculus, frontooccipital fasciculus, etc.) correlated with specific domains of cognitive function in ET patients. Conclusion These data suggest that not only the cerebello thalamocortical pathway, but numerous other brain structures are related to level of cognitive performance and possibly underlie cognitive dysfunction in ET.

Toksik metabolik ensefalopatiler, metabolizma bozuklukları sonucu ortaya çıkan ürünler veya maruz kalınan ekzojen toksinlerin SSS üzerinde yan etki oluşturabilmesi sonucu ani başlangıçlı bilinç bulanıklığı, fokal nörolojik defisit, davranış değişiklikleri ve/veya nöbet gelişimi gibi nonspesifik semptomlar ile sonuçlanan serebral fonksiyon bozukluğudur. Bu etki genellikle derin gri cevher, beyaz cevher ve serebral korteks tutulumu ile seyretmekte ve simetrik ve diffüz tutulum alanları oluşturmaktadır. Patofizyolojisi multifaktoriyel olup etiyolojiye göre değişebilmekte ve genellikle nöroinflamasyon, nörotransmisyonda bozulma veya sitotoksik hasar sonucu ortaya çıkmaktadır. Maruziyet süresine bağlı olarak geri dönüşümsüz mikroyapısal değişikliklere yol açabilmektedir. Erken dönemde MRG nörolojik disfonksiyon ile sonuçlanan akut tutulum alanlarını göstermede, kronik dönemde ise nörolojik sekel gelişimini öngörmede yardımcıdır. Ancak klinik durum ve beyin lezyonlarının yayılımı ve ciddiyeti bazı durumlarda örtüşmeyebilmektedir. Ortaya çıkan semptomların nonspesifik olması sebebiyle görüntüleme bulgularının tanınabilmesi etiyolojiyi belirleme açısından önemlidir. Ayrıca maruz kalınan toksik ajanların ve lezyonların topografik yayılımlarının bilinmesi de diğer ensefalopati oluşturan durumları ekarte etmek açısından faydalıdır. Bu yazıda günlük pratikte daha sık karşılaştığımız ve görüntüleme bulgularının tanınması ile ayırıcı tanı oluşturmada kolaylık sağlayacağını düşündüğümüz bazı kazanılmış metabolik ve toksik ensefalapatiler sunulmuştur.

Background: In spite of the fact that advanced neuroimaging applications are used for the evaluation of Tuberous Sclerosis (TS) patients, a few studies analyzed relationship between the measurements of DTI (diffusion tensor imaging) and neurological findings.

We aimed to evaluate the differences between apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values obtained from different cranial sites in subjects with Chiari I Malformation (CM-I) and borderline tonsillar ectopia (BTE), and to determine correlations between diffusion tensor imaging (DTI) metrics and the severity of tonsillar ectopia. A total of 73 subjects with CM-I and BTE and 35 control underwent MRI and DTI. In our study, ADC values measured from the level of medulla oblongata and the RD values measured in middle cerebellar peduncles, thalamus, and globus pallidus were higher in CM-I patients than in controls. FA values at the medulla oblongata level and AD values at the medulla oblongata and pons level higher in patients with CM-I. ADC and AD values measured at the pons level were higher in BTE subjects than in controls. Compared with BTE, the CM-I subjects- ADC values at the medulla oblongata and AD values at the pons level were higher. In addition, FAs at the pons and medulla oblongata level were higher. At the medulla oblongata level, a positive correlation was observed between ADC and the size of tonsillar ectopia. AD and FA values measured at the level of medulla oblongata and pons were positively correlated with the size of tonsillar ectopia. These findings may be related to the severity of microstructural changes involving neuronal tracts at the brainstem level due to tonsillar ectopia. DTI may be useful in determining the extent of microstructural changes at the tissue level in subjects with tonsillar ectopia.

We aimed to evaluate the change in bilateral auditory pathways using diffusion tensor imaging (DTI) after gamma knife radiosurgery (GKR) and to determine the relationship between the radiosurgical treatment variables and DTI findings. In this study 13 patients with unilateral acoustic neuroma and 11 controls underwent routine magnetic resonance imaging (MRI) and DTI. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured from the bilateral auditory pathways in all individuals before and after GKR. Before GKR, subjects’ ADC values obtained from the contralateral side were higher at the lateral lemniscus, medial geniculate body and Heschl’s gyrus compared to those of the controls. No statistical differences were found in ADC and FA obtained at bilateral auditory pathways before and after GKR. The ADCs measured at the lateral lemniscus were positively correlated with the maximum radiation dose delivered to the brainstem (BS) and the brainstem volume receiving a radiation dose of 10 Gy (BS V10). A negative correlation was found between the FA measured from the inferior colliculus and the maximum radiation dose to the cochlea. The ADCs at the inferior colliculus were positively correlated with the mean radiation dose to the cochlea. There were no significant differences in the degree of involvement before and after GKR, revealing that GKR did not significantly affect the auditory pathways at 4 months. The major factors that may lead to microstructural injury to auditory pathways at the brainstem level are associated with maximum brainstem radiation dose, BS V10, and cochlear dose. These findings may suggest that more attention should be paid to anatomical structures including the cochlea and brainstem during treatment planning of GKR.

Background: This study aims to investigate the existence of any Diffusion Tensor Imaging (DTI) value differences in Brain Metastases (BM) due to lung adenocarcinoma based on the Epidermal Growth Factor Receptor (EGFR) gene mutation status. Material and Methods: 17 patients with 32 solid intracranial metastatic lesions from lung adenocarcinoma were included prospectively. Patients were divided according to the EGFR mutation status as EGFR (+) (group 1, n:8) and EGFR wild type (group 2, n:9). The Fractional Anisotropy (FA), apparent diffusion coefficient (ADC), normalized ADC (nADC), Axial Diffusivity (AD), and Radial Diffusivity (RD) values were measured from the solid component of the metastatic lesions and nADC values were calculated. DTI values were compared between group 1 and group 2. The receiver-operating characteristic analysis was used to obtain cut-off values for the parameters presenting a statistical difference between the EGFR gene mutation-positive and wild type group. Results: There were statistically significant differences in measured ADC, nADC, AD, and RD values between group 1 and group 2. The ADC, nADC, AD, and RD values were significantly lower in group 1. There was no significant difference in FA values between the two groups. Analysis by the ROC curve method revealed a cut-off value of ≤721 x 10-6 mm2/s for ADC (Sensitivity= 72.7, Specificity=85.7); ≤0.820 for nADC (Sensitivity=72.7, Specificity=90.5), ≤ 886 for AD (Sensitivity=81.8, Specificity=81.0), and ≤588 for RD (Sensitivity=63.6, Specificity=90.5) in differentiating EGFR mutation (+) group from wild type group. Conclusion: A combination of the decreased ADC, nADC, AD, and RD values in BM due to lung adenocarcinoma can be important for predicting the EGFR gene mutation status. DTI features of the brain metastases from lung adenocarcinoma may be utilized to provide insight into the EGFR mutation status and guide the clinicians for the initiation of targeted therapy.

To evaluate the MRI findings of solid parathyroid lesions and to elaborate on a possible improvement of MRI detection of parathyroid lesions by the use of additional DWI. MRI and DWI properties of pathologically proven 20 solid parathyroid lesions were retrospectively reviewed. Mean ADC values (b50 + b400 + b800/3) of parathyroid lesions were compared with that of normal appearing thyroid parenchyma (TP), sternocleidomastoid muscle (SCM) and jugulodigastric lymph nodes (JDLN). Of lesions, 4 were parathyroid hyperplasia, 13 parathyroid adenoma and 3 parathyroid adenocarcinoma. All parathyroid lesions were very bright on fat-saturated T2W images. Parathyroid hyperplasia and adenoma were small sized, homogenous, well-defined and low on T1W, high on T2W and avidly enhancing. Parathyroid carcinoma was large sized, ill-defined and very heterogeneous on MRI including DWI. Means ADC values of parathyroid hyperplasia, adenoma, and adenocarcinoma, TP, SCM and JDLN were measured as 2.3 ± 0.14 × 10−3, 1.7 ± 0.45 × 10−3, 1.5 ± 1.48 × 10−3, 0.87 ± 0.40 × 10−3, 0.55 ± 0.21 × 10−3 and 0.96 ± 0.33 × 10−3 mm2/s, respectively. All parathyroid lesions had high diffusion properties comparing other soft tissue structures of head and neck region. By increasing strength (b value) of diffusion tensor on DWI, solid parathyroid lesions still kept their brightness comparing other soft tissue structures of head and neck region because of their high T2 properties. Solid parathyroid lesions had higher diffusion properties comparing other soft tissues structures of head and neck region. This feature makes them easily differentiate from nearby structures on fat-saturated T2W and DWI.