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Item The prognostic value of mean apparent diffusion coefficient measured with diffusion-weighted magnetic resonance image in patients with prostate cancer treated with definitive radiotherapy(2022) Onal, Cem; Erbay, Gurcan; Guler, Ozan Cem; Oymak, Ezgi; 35753556Purpose: To assess the correlation between initial tumor apparent diffusion coefficient (ADC) values and clinicopathological parameters in prostate cancer (PCa) patients treated with definitive radiotherapy (RT). Additionally, the prognostic factors for freedom from biochemical failure (FFBF) and progressionfree survival (PFS) in this patient cohort were analyzed. Materials and methods: The clinical data of 503 patients with biopsy-confirmed PCa were evaluated retrospectively. All patients had clearly evident tumors on diffusion-weighted magnetic resonance imaging (DW-MRI) for ADC values. Univariable and multivariable analyses were used to determine prognostic factors for FFBF and PFS. Results: The median follow-up was 72.9 months. The 5-year FFBF and PFS rates were 93.2% and 86.2%, respectively. Significantly lower ADC values were found in patients with a high PSA level; advanced clinical stage; higher ISUP score, and higher risk group than their counterparts. Receiver operating characteristic (ROC) curve analysis revealed an ADC cut-off value of 0.737 x 10-3 mm2/sec for tumor recurrence. Patients who progressed had a lower mean ADC value than those who did not (0.712 +/- 0.158 vs. 1.365 +/- 0. 227 x 10-3 mm2/sec; p < 0.001). There was a significant difference in 5-year FFBF (96.3% vs. 90%; p < 0.001) and PFS rates (83.8% vs. 73.5%; p = 0.002) between patients with higher and lower mean ADC values. The FFBF and PFS were found to be correlated with tumor ADC value and ISUP grades in multivariable analysis. Additionally, older age was found to be a significant predictor of worse PFS. Conclusions: Lower ADC values were found in patients with high-risk characteristics such as a high serum PSA level, stage or grade of tumor, or high-risk disease, implying that ADC values could be used to predict prognosis. Lower ADC values and higher ISUP grades were associated with an increased risk of BF and progression, implying that treatment intensification may be required in these patients. (c) 2022 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 173 (2022) 285-291Item Evaluation of cortical thickness and brain volume on 3 Tesla magnetic resonance imaging in children with frontal lobe epilepsy(2020) Rahatli, Feride Kural; Sezer, Taner; Has, Arzu Ceylan; Agildere, Ahmet Muhtesem; 0000-0002-2278-1827; 0000-0003-4223-7017; 0000-0002-4226-4034; 31802343; AAJ-5931-2021; AAB-5802-2020; AAL-9808-2021Background Frontal lobe epilepsy (FLE) is the most common epilepsy syndrome in the pediatric population; however, brain magnetic resonance imaging (MRI) of the children with FLE is frequently normal. We use both cortical thickness and brain volume measurements to report on cortical changes in children with FLE. Our aim was to determine cortical thickness and brain volume changes on 3 Tesla MRI of children with FLE and normal brain magnetic resonance imaging. Methods Twenty-seven children with FLE and 27 healthy controls received brain magnetic resonance imaging. Cortical thickness and regional brain volumes were assessed using three-dimensional volumetric T1-weighted imaging and patients were compared with controls. Results In children with FLE, statistically significant (p < 0.05) cortical thinning were found in the bilateral middle frontal gyrus, bilateral occipitotemporal and medial lingual gyrus, left subcallosal gyrus, left short insular gyrus, and right long insular gyrus. Statistically significant volume reductions in right and left hemisphere cortical white matter, total cortical white matter, bilateral thalamus, bilateral putamen, bilateral globus pallidus, right caudate nucleus, brain stem, and right cerebellar cortex were found. Conclusion Cortical thinning in frontal and extra-frontal lobes and volume loss in a variety of brain regions were found in children with FLE.Item Significance of the Cerebellopontine Cistern Cross-Sectional Area and Trigeminal Nerve Anatomy in Trigeminal Neuralgia: An Anatomical Study Using Magnetic Resonance Imaging(2020) Gunesli, Aylin; Tufan, Kadir; 0000-0003-1509-4575; 32091126; AAK-1686-2021AIM: To evaluate the relationship between trigeminal neuralgia (TN) and potential magnetic resonance imaging (MRI)-related measurements in patients with TN. MATERIAL and METHODS: Retrospective analysis of 104 patients with TN was performed. MRI studies of 98 healthy controls were included in the study to compare the parameters with TN patients' measurements. MRI measurements of cerebellopontine cistern (CPC) cross-sectional area, trigeminal-pontine angle (TPA) width, and trigeminal nerve cisternal segment length and thickness were assessed on both symptomatic and asymptomatic sides using 1.5T MRI with constructive interference in steady-state sequences. The images were interpreted by two radiologists blinded to the affected sides of the patients. RESULTS: There were significant differences between the symptomatic and asymptomatic sides in terms of mean trigeminal nerve length (8.8 +/- 2.34 mm vs. 9.39 +/- 2.29 mm; respectively, p=0.001) and thickness (20.9 +/- 9.6 mm(2) vs. 25 +/- 9.98 mm(2), respectively; p<0.001). The median cerebellopontine cistern cross-sectional area was considerably lower on the symptomatic side compared with the asymptomatic side [201 mm(2) (interquartile range=93) vs. 224.5 mm(2) (interquartile range=77), respectively; p<0.001]. There were no significant differences between the trigeminal-pontine angle width on either side (38.32 +/- 10.38 vs. 38.78 +/- 10.9, respectively; p=0.679). There were no statistically significant differences between the right and left sides regarding these parameters in the control group. CONCLUSION: Smaller CPC cross-sectional area, trigeminal nerve length, and trigeminal nerve thickness on MRI were demonstrated to commonly exist on the symptomatic side in patients with TN. We suggest that this narrow space may increase the risk of vascular compression on the nerve.Item A Novel Deep Learning Algorithm for the Automatic Detection of High-Grade Gliomas on T2-Weighted Magnetic Resonance I mages: A Preliminary Machine Learning Study(2020) Atici, Mehmet Ali; Sagiroglu, Seref; Celtikci, Pinar; Ucar, Murat; Borcek, Alp Ozgun; Emmez, Hakan; Celtikci, Emrah; 0000-0002-1655-6957; 31608975AIM: To propose a convolutional neural network (CNN) for the automatic detection of high-grade gliomas (HGGs) on T2-weighted magnetic resonance imaging (MRI) scans. MATERIAL and METHODS: A total of 3580 images obtained from 179 individuals were used for training and validation. After random rotation and vertical flip, training data was augmented by factor of 10 in each iteration. In order to increase data processing time, every single image converted into a Jpeg image which has a resolution of 320x320. Accuracy, precision and recall rates were calculated after training of the algorithm. RESULTS: Following training, CNN achieved acceptable performance ratios of 0.854 to 0.944 for accuracy, 0.812 to 0.980 for precision and 0.738 to 0.907 for recall. Also, CNN was able to detect HGG cases even though there is no apparent mass lesion in the given image. CONCLUSION: Our preliminary findings demonstrate; currently proposed CNN model achieves acceptable performance results for the automatic detection of HGGs on T2-weighted images.Item Predictors of progression in primary progressive multiple sclerosis in a large Turkish cohort(2020) Vural, Atay; Derle, Eda; Sayat-Gurel, Guliz; Karabudak, Rana; Tuncer, Asli; 0000-0003-2122-1016; 31743849; AAI-8830-2021Background: Studies on the predictors of progression for primary progressive multiple sclerosis (PPMS) are limited and there is no information in the literature for populations outside Europe and North America. In this study, we aimed to identify predictors of progression in a large Turkish PPMS cohort. Methods: We analyzed a cohort of 157 PPMS patients to investigate the effect of age of onset, gender, onset symptoms, presence or absence of relapses, and baseline gadolinium-enhancing lesions on the rate of progression to EDSS6 by using Kaplan-Meier analysis and multivariate Cox regression. Results: Older age of onset and presence of spinal motor symptoms at onset were associated with a shorter time to EDSS6 and presence of supratentorial signs at onset was associated with a longer time to EDSS6 according to Kaplan-Meier analysis. These factors remained significant after multivariate Cox-regression analysis. Clinical relapses were present in 22.3% and gadolinium-enhancing lesions on baseline MRI were present in 28% of patients, but these factors were not predictive of time to EDSS6. Conclusion: We identified age of onset and symptom at onset as predictors of progression in Turkish PPMS patients. Presence of clinical relapses or baseline gadolinium-enhancing lesions did not affect PPMS progression rate.Item Is fetal magnetic resonance imaging indicated in patients with isolated ventriculomegaly?(2019) Durdag, Gulsen Dogan; Baran, Safak Yilmaz; Kalayci, Hakan; Alkan, Ozlem; 0000-0001-5874-7324; 31228676; ABF-6439-2020Objective: Ventriculomegaly is one of the most common anomalies encountered at obstetric ultrasound and it necessitates follow up. Fetal magnetic resonance imaging (MRI) can be used to confirm the ultrasound diagnose or to detect additional anomalies. Aim of this study is to assess follow up and management of fetal ventriculomegaly shown by ultrasound, and to evaluate additional diagnostic contribution of MRI. Study Design: This study was conducted retrospectively including 89 patients who had fetal MRI subsequent to ultrasound diagnose of ventriculomegaly in between 2011-2017. Medical records of patients were investigated and accompanying anomalies, congenital infection. chromosomal examination, degree and progression of ventriculomegaly, neonatal imaging and diagnose, and neurodevelopmental findings on follow up were evaluated. Patients were classified in two groups as isolated and nonisolated ventriculomegaly, and subgroups mild, moderate, severe were formed according to their findings. SPSS 23.0 programme was used for statistical analysis. Results: Ultrasound and following MRI was performed in a range of 18-35 th gestational weeks, diagnoses were isolated ventriculomegaly for 56 patients and nonisolated ventriculomegaly for 33 patients. Progression and neurodevelopmental delay was higher in severe nonisolated ventriculomegaly group. There was not significant contribution of MRI in the follow up of isolated ventriculomegaly (p < 0.001), and diagnostic imaging findings declined in neonatal period with proceeding normal neurodevelopment in 92.7% of patients followed with diagnosis of isolated ventriculomegaly. Conclusion: When isolated ventriculomegaly is detected, ultrasound performed by an experienced team is mostly sufficient. MRI can be used in suspicious cases or when ventriculomegaly progresses. (C) 2019 Elsevier B.V. All rights reserved.Item Efficiency of pivot splints as jaw exercise apparatus in combination with stabilization splints in anterior disc displacement without reduction: a retrospective study(2014) Muhtarogullari, Mehmet; Avci, Mehmet; Yuzugullu, Bulem; 25300939Objective: To evaluate efficiency of pivot splints in jaw exercises, in combination with stabilization splints, in cases of anterior disc displacement without reduction of temporomandibular joint. Subjects and methods: Twenty-three patients who referred to the prosthodontics clinic in 1995-1997 were included in the study, where anterior disc displacement without reduction of temporomandibular joint was diagnosed using magnetic resonance imaging and clinical examination. Pivot splints were used for jaw exercises for five minutes long; five times/day and stabilization splints were used at all other times. The patients were followed for 24 weeks. Lateral and protrusive excursions along with maximum mouth opening and were evaluated at each control. Bilateral palpation of temporal, masseter, sternocleidomastoid muscles and TMJ was assessed for pain perception before and after treatment. Data were statistically analyzed using Paired sample t-test and Independent Samples t-test (p < .05). Results: Mean mandibular range of motion measurements increased from 28.74 mm prior to 49.17 mm on maximum opening; right/left lateral excursion from 7.61 mm to 12.04 mm and 4.09 mm to 7.3 mm on protrusion after treatment. All changes observed before and after treatment were found to be statistically significant. (p < .001) Pain symptoms were eliminated at the end of 24 weeks of treatment in all patients. Conclusion: Using pivot splints as an exercise regimen along with a stabilization splint may be a viable treatment option for patients with anterior disc displacement without reduction; as normal mandibular range of motion was established and pain was eliminated.Item Intrathecal Methotrexate-Induced Posterior Reversible Encephalopathy Syndrome (PRES)(2014) Guler, Tulay; Cakmak, Ozden Yener; Toprak, Selami Kocak; Kibaroglu, Seda; Can, Ufuk; 24764745Item Imaging findings of spondylodiscitis(2016) Alkan, Ozlem; Altinkaya, NaimeSpondylodiscitis is an infection of the intervertebral disc and adjacent vertebral bodies. Magnetic resonance imaging is the method of choice for the spondylodiscitis. The characteristic findings in the spondylodiscitis are hypointense on T1-weighted (W) image and hyperintense on T2W and fat-saturation T2W images, contrast enhancement on contrast-enhanced T1W with fat saturation images in the disc space and adjacent vertebral bodies, and phlegmon or abscess of the paraspinal soft tissues and epidural space. Phlegmon shows homogenous contrast enhancement, while abscess shows peripheral ring-enhancement on contrast-enhanced T1W with fat saturation images. Differentiation of tuberculous, brucellar and pyogenic spondylodiscitis is radiological difficult. Features that also favor tuberculosis infection include multilevel disease, large paravertebral abscess, meningeal involvement and subligamentous spread. Brucellar spondylodiscitis most commonly affects the lumbar spine. Bone destruction is less severe than in tuberculous spondylodiscitis. Osteophyte formation at the anterior vertebral endplate is typical.Item Liver Perivascular Epithelioid Cell Tumor with an Unusual Location: Diagnostic Characteristics with Multidetector Computed Tomography and Magnetic Resonance Imaging(2017) Hekimoglu, Koray; Haberal, Murat; 0000-0002-0805-0841; 0000-0002-8211-4065; 28975043; AAD-9097-2021; R-9398-2019Primary perivascular epithelioid cell tumor (PEComa) of the liver is a very rare tumor that originates from mesenchyma. Gastrointestinal tract with perivascular distribution is the most common anatomic sites of these tumors. Only few cases of hepatic PEComa have been described so far. Malignant PEComas exhibit aggressive behavior with poor prognosis, making early diagnosis crucial. Hereby, we report a 79-year-old female with unusually located mass in the liver. A partial curative hepatectomy has been done, and PEComa was diagnosed histopathologically. No evidence of recurrence was observed during the 6-month follow-up.