A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology

PURPOSE:Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables.METHODS:A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps of VBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables.RESULTS:Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05).CONCLUSION:Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia

Multiparametric MRI guidance in first-time prostate biopsies: what is the real benefit?

PURPOSEWith the increased recognition of the capabilities of prostate multiparametric (mp) magnetic resonance imaging (MRI), attempts are being made to incorporate MRI into routine prostate biopsies. In this study, we aimed to analyze the diagnostic yield via cognitive fusion, transrectal ultrasound (TRUS)-guided, and in-bore MRI-guided biopsies in biopsy-naive patients with positive findings for prostate cancer screening.METHODSCharts of 140 patients, who underwent transrectal prostate biopsy after the adaptation of mp-MRI into our routine clinical practice, were reviewed retrospectively. Patients with previous negative biopsies (n=24) and digital rectal examination findings suspicious for ≥cT3 prostate cancer (n=16) were excluded. T2-weighted imaging, diffusion-weighted imaging, and dynamic contrast-enhanced imaging were included in mp-MRI. Cognitive fusion biopsies were performed after a review of mp-MRI data, whereas TRUS-guided biopsies were performed blinded to MRI information. In-bore biopsies were conducted by means of real-time targeting under MRI guidance. RESULTSBetween January 2012 and February 2014, a total of 100 patients fulfilling the inclusion criteria underwent TRUS-guided (n=37), cognitive fusion (n=49), and in-bore (n=14) biopsies. Mean age, serum prostate specific antigen level, and prostate size did not differ significantly among the study groups. In TRUS-guided biopsy group, 51.3% were diagnosed with prostate cancer, while the same ratio was 55.1% and 71.4% in cognitive fusion and in-bore biopsy groups, respectively (P = 0.429). Clinically significant prostate cancer detection rate was 69.1%, 70.3%, and 90% in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively (P = 0.31). According to histopathologic variables in the prostatectomy specimen, significant prostate cancer was detected in 85.7%, 93.3%, and 100% of patients in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively. CONCLUSIONIn the first set of transrectal prostate biopsies, mp-MRI guidance did not increase the diagnostic yield significantly

Language lateralization in temporal lobe epilepsy: A functional magnetic resonance imaging study

TLE eriskinde epilepsinin en sık görülen türüdür. Dil islevi ile ilişkili beyin alanlarının, cerrahi öncesi dönemde yerlesiminin ve yanlasmasının belirlenmesi cerrahi sonrası nörolojik defisitlerin en aza indirilmesi açısından büyük klinik önem tasımaktadır. Fonksiyonel manyetik rezonans görüntüleme, dil lateralizasyonunun degerlendirilmesinde gelecek vaat eden bir görüntüleme yöntemidir. Bu çalısmanın amacı, TLE olgularının cerrahi öncesi degerlendirilmesinde klinik kullanıma uygun, FMRG deney desenleri hazırlamaktır. Onbes TLE olgusu ve 15 saglıklı, gönüllü birey çalısmaya katılmıstır. nceleme, yüksek çözünürlüklü T1 agırlıklı anatomik verilerin alınmasını takiben, GRE EPG sekansında fonksiyonel görüntülerin alınmasıyla tamamlanmıstır. Çalısmaya katılan tüm bireylerde konusma alanlarının yanallastırılması için Kelime üretme görevi-1 (KÜG-1) ve kelime üretme görevi-2 (KÜG-2) yi içeren iki farklı FMRG deney deseni kullanılmıstır. KÜG -1 de pasif kontrol kosulları, gerçek dinlenme süreci kullanılarak olusturulmustur. KÜG-2 de anlamsız sözdizinleri kullanılarak aktif kontrol kosulları olusturulmustur. Grup analizleri ve tek birey analizleri Brain Voyager QX kullanılarak elde olunmustur. KÜG-1 sırasında frontal, temporal ve pariatel bölgelerde bilateral, yaygın aktivasyon sinyalleri olusmustur. KÜG-2, sırasında frontal ve temporal bölgelerde, güçlü bir sekilde sol lateralizasyon gösteren aktivasyon sinyalleri olusmustur. KÜG-2 sırasında parietal bölgede aktivasyon sinyalleri izlenmemiş olup frontal ve temporal aktivasyonlar KÜG-1 ile karsılastırıldıgında küçük bir alana uzanmaktadır. KÜG-2 tek basına kullanılırsa yalancı negatif sonuçlar izlenebilmektedir. Bununla birlikte, süperior temporal girusta KÜG-2, KÜG-1 e oranla daha güçlü aktivasyon sinyallerinin olusumuna sebep olmustur. Süperior temporal girus epilepsi cerrahisinde hedef beyin alanı olarak kabul edilmekte olup algısal konusma islevinde anahtar role sahiptir. Bu çalısmanın bulguları, dil islevi ile iliskili kortikal alanların dogru olarak lateralizasyonunun yapılabilmesi ve yerlesiminin belirlenmesi için KÜG-II nin KÜG-I i tamamlayıcı nitelikte oldugunu göstermektedir.TLE is the most frequent type of epilepsy in adult population. Preoperative localization and assesment of laterality of language areas are essential in epilepsy surgery to prevent postoperative neurological deficitis. FMRI is a promising imaging tool for assesment of laterality of language areas. The aim of this study is to develop a clinical FMRI language design for presurgical evaluation of TLE patients. Fifteen patients with TLE and 15 healthy, volunteers were included in the study. Following the acquisition of high-resolution T1-weighted anatomical reference images, functional imaging was obtained by gradient-echo EPI sequence. Two different FMRI paradigms as Verb Generation Task-1 (VGT-1), Verb Generation Task-2 (VGT-2) were used in each subject for the lateralization of the language areas. VGT-1 has passive baseline conditions with true rests. Baseline conditions of VGT-2 include active state with the use of nonsense words. Group analyses and individual-subject analysis were done by Brain Voyager QX software. By using VGT-1, largely bilateral activations in frontal, temporal and parietal regions were obtained. With VGT-2, strongly left lateralized activations in frontal and temporal regions were obtained. During VGT-2, parietal regions were not activated and when compared with VGT-1, frontal and temporal activation signals were small in size. False-negative activation can be seen when only VGT-II was used. However, VGT-2 provided more robust activations in superior temporal gyrus then VGT-1. Superior temporal gyrus is known as a target region for epilepsy surgery that has a key role in receptive language function. Our results show that VGT-2 can be used as a complementy technique of VGT-1 for accurate lateralization of all critical language cortical areas

Üniversite Öğrencilerinin Bilgisayar Oyunu Oynama Alışkanlıkları ve Oyun Tercihleri: ODTÜ ve Gazi Üniversitesi Öğrencileri Arasındaki Karşılaştırmalı Bir Çalışma

Bu araştırma üniversite öğrencileri arasında bilgisayar oyunu oynama alışkanlıklarını ve oyun tercihlerini belirlemek amacıyla yapılmıştır. Orta Doğu Teknik Üniversitesinden 225 ve Gazi Üniversitesinden 271 öğrencinin katılımcı olarak yer aldığı çalışmada bilgisayar kullanma, bilgisayar oyunu oynama ve oyun tercihleri gibi konular incelenmiştir. Araştırmanın sonuçları göstermiştir ki öğrencilerin ortalama oyun oynama süreleri literatürdekine benzerlik göstermektedir. En çok tercih edilen oyun türleri strateji, yarış ve aksiyon/serüven olarak ortaya çıkmaktadır. En çok tercih edilen oyun temaları ise serüven ve keşif olarak belirlenmiştir. Oyun oynama nedeni olarak çoğunlukla stres atma gösterilmektedir. Literatürde olduğu gibi ODTU'deki katılımcılar arasında erkekler bayanlara göre daha fazla oyun oynamakta ve oyun tür ve tema tercihleri cinsiyete göre farklılık gösterirken Gazi Üniversitesi katılımcıları arasında anlamlı bir fark gözlenmemektedir

b-talasemi hastalarında MLPA yöntemi ile HBA mutasyonlarının saptanması

Thalassemia syndromes are the most common monogenic disorders in humans and b-thalassemia major is one of the most important public health problems in Turkey. Many genetic factors play roles in modifying the disease severity such as mutations in the alpha globin gene (HBA), UGT1 gene (bilirubin metabolism) or HFE gene (iron metabolism). Deletions or duplications in HBA gene determine the accumulation of a chain in b-thalassemia major patients. The human alpha globin gene cluster is located on chromosome 16 and deletions or duplications are the most important mutations. Multiple ligation dependent probe amplification (MLPA) technique is a simple and rapid technique and used in many genetic disorders in which deletions and duplications are common. In this study we used a commercial MLPA kit for detecting alpha globin gene mutations. The kit contains 24 different probes in the HBA region. In this study we aimed to investigate the incidence of alpha globin gene mutations using MLPA technique in 19 b-thalassemia major patients which were diagnosed in our departmentAlpha globin gene deletions were detected in 2 out of 19 (10.5%) b-thalassemia major patients. In one of the patients the deletion was located between the HBA2 gene and HBA1P gene. The deletion detected in the other patient was located between the HBA1 gene and HBA2 gene. This result suggests that alpha globin gene mutations in b-thalassemia major patients are not rare. MLPA technique is suitable to investigate the mutations in this complex gene cluster.Talasemi sendromları insanlarda en sık gözlenen monogenik hastalıklardır b-talasemi major ülkemizde gözlenen en önemli halk sağlığı problemlerinden birisidir. HBA (alfa globin), UGT1 (bilirübin metabolizması), HFE (demir metabolizması) genlerindeki mutasyonlar gibi genetik düzenleyici faktörler hastalığın ağırlığının belirlenmesinde önemli role sahiptir. HBA genindeki delesyon ya da duplikasyonlar b-talasemi major hastalarındaki a-zincir birikiminin miktarını belirlemektedir. HBA geni 16. Kromozom üzerinde lokalizedir ve gende gözlenen mutasyonları büyük oranda delesyon ve duplikasyonlar oluşturmaktadır. Multiple ligation dependent probe amplification (MLPA) tekniği, delesyon ve duplikasyonların sık olarak gözlendiği genetik hastalıkların tanısında kullanılabilen yeni, basit ve hızlı bir yöntemdir. Bu çalışmada 24 adet prob ile HBA genindeki delesyon ya da duplikasyonları saptayabilen ticari bir kit kullanılmıştır. Bu çalışmada bölümümüzde b-talasemi major hastalığı tanısı almış 19 hastada HBA genindeki mutasyonlar MLPA yöntemi ile araştırılmıştır. On dokuz hastanın 2' sinde (%10.5) HBA geninde delesyon saptanmıştır. Hastaların bir tanesinde delesyon HBA2 geni HBAİP arasında, diğerinde HBA1 ile HBA2 genleri arasında saptanmıştır. Bü sonuç b-talasemi major hastaları arasında HBA gen mutasyonların nadir olmadığını göstermektedir. Ayrıca MLPA tekniğinin bu kompleks gen dizisindeki mutasyonların araştırılmasında uygun bir teknik olduğu da görülmüştür

Conspicuity of Peripheral Zone Prostate Cancer on Computed Diffusion-Weighted Imaging: Comparison of cDWI1500, cDWI2000, and cDWI3000

Introduction and Objective. Disadvantages associated with direct high b-value measurements may be avoided with use of computed diffusion-weighted imaging (cDWI). The purpose of this study is to assess the diagnostic performance of cDWI image sets calculated for high b-values of 1500, 2000, and 3000 s/mm2. Materials and Methods. Twenty-eight patients who underwent multiparametric MRI of the prostate and radical prostatectomy consecutively were enrolled in this retrospective study. Using a software developed at our institute, cDWI1500, cDWI2000, and cDWI3000 image sets were generated by fitting a monoexponential model. Index lesions on cDWI image sets were scored by two radiologists in consensus considering lesion conspicuity, suppression of background prostate tissue, distortion, image set preferability, and contrast ratio measurements were performed. Results. Lesion detection rates are the same for computed b-values of 2000 and 3000 s/mm2 and are better than b-values of 1500 s/mm2. Best lesion conspicuity and best background prostate tissue suppression are provided by cDWI3000 image set. cDWI2000 image set provides the best zonal anatomical delineation and less distortion and was chosen as the most preferred image set. Average contrast ratio measured on these image sets shows almost a linear relation with the b-values. Conclusion. cDWI2000 image set with similar conspicuity and the same lesion detection rate, but better zonal anatomical delineation, and less distortion, was chosen as the preferable image set