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WOS: 000337898000004 Purpose: The aim of our study is to investigate the contribution of DWI, DCE-MRI, ADC measurements and T2 relaxometry in diagnosis of distinguishing cholesteatoma and COM Materials and Methods: Our study is created by retrospectively reviewing MR images of a digital archive of totally 41 patients that were clinically or surgically diagnosed as COM and cholesteatoma. DWI, ADC values, T2 relaxation time, and CEP of lesions between the two groups were compared statistically. CEP was qualitatively evaluated. ROC analysis and McNemar statistics test were performed. Level of significance was determined as p0.05). When the groups were assessed according to the CEP, 13 of the COM cases showed type 1 (progressive heterogeneous enhancement), 2 cases did not show enhancement (type 3) and 6 cases showed type 4 (progressive homogeneous enhancement). Nineteen patients with cholesteatoma showed type 2 (rim-like enhancement), 1 case showed type 4. Statistical analysis of CEP revealed significant differences between types 1 and 2 (p

The aim of this study to compare different magnetic resonance (MR) pulse sequences and computed tomography (CT) in the detection of subacute subarachnoid hemorrhage (SAH) in subacute stages. Twenty-seven patients underwent MRI and CT examination who were suspected to have SAH. MRI (1.5-T) pulse sequences comprised spin-echo T1-weighted, fast spin-echo T2-weighted, fluild attenuated inversion recovery (FLAIR), and gradient-echo (GE) T2-weighted images. We aimed to determine the efficacy of MRI pulse sequences relative to CT in diagnosis of hemorrhage at 6 different localizations.Digital substraction angiography (DSA) were performed in all patients. Among all the techniques, FLAIR is the most sensitive one superior to CT in diagnosis of hemorrhage at all localizations except intraventricular hemorrhage. FLAIR is statistically significant indicators of subacute SAH whereas other MRI pulse sequences, and CT scans, are not., Subakut dönem (>3 gün) subaraknoid kanama (SAK) tanısında bilgisayarlı tomografi (BT), T1-ağırlıklı spin eko (SE), T2-ağırlıklı fast spin eko (FSE), fluid attenuated inversion recovery (FLAIR) ve T2-ağırlıklı gradiyent eko (GRE) sekanslarının etkinliğinin değerlendirilmesi amaçlandı. Uludağ Üniversitesi Tıp Fakültesi Radyoloji AnaBilim Dalı'na SAK şüphesi ile gönderilen, 3 -14 gün arasında semptomları olan 14'ü erkek, 13'ü kadın toplam 27 olgu çalışma kapsamında değerlendirildi. Olgulara kontrastsız BT ve MR ile birlikte, serebral dijital subtraksiyon anjiyografi (DSA) incelemeleri yapıldı. Altı ayrı standart lokalizasyonda (interhemisferik fissür, bazal sisternalar, kortikal sulkuslar, sylvian fissür, intraventriküler, intraparenkimal) kanama araştırıldı. Kanama saptanmasında MR sekanslarının BT incelemeye göre etkinliği araştırıldı. Bulguların istatistiksel değerlendirmesi için McNemar testi kullanıldı. Bu teste göre p> 0.05 anlamlı değil, p< 0.05 anlamlı, p< 0.01 belirgin anlamlı kabul edildi. FLAIR sekansı intraventriküler kanama dışında tüm lokalizasyonlarda SAK saptanmasında BT'den istatistiksel anlamlı şekilde üstündü (p< 0.05). FLAIR sekansı, intraventriküler kanama dışında tüm lokalizasyonlarda subakut dönemde SAK'ı saptamakta BT'ye göre üstün olan en duyarlı MR sekansıdır.

Astrocytic tumors have the propensity to change from low-grade to high-grade lesions. Though, it is sometimes difficult to differentiate the two histopathologic entities with conventional MRI (magnetic resonance imaging) findings only. In such circumstances, perfusion MRI with its ability to demonstrate tumoral vascularity indirectly and MR spectroscopy highlighting cellular metabolism can provide additional information about physiology. In this case, we reported the progression of a low-grade tumor into a high-grade lesion with the conventional and perfusion MRI and also MR spectroscopy findings in the light of the literature. In high-grade tumors, apparently high rCBV ratios were depicted as a result of vascular proliferation. Remarkable increase of the cholin peak, moderate increase of the lactate peak and apparent decrease of the n-acetyl aspartate peak were identified at MR spectroscopy., Astrositik tümörler çoğunlukla düşük-evreden yüksek evreli lezyona dönüşme eğilimi gösterirler. Konvansiyonel manyetik rezonans (MR) bulguları ile bu iki farklı histopatolojik lezyonun ayrımı bazen güç olabilmektedir. Bu durumda tümöral vaskülariteyi dolaylı gösteren perfüzyon MR ve hücresel metabolizmayı ortaya koyan MR spektroskopi bize fonksiyonel ilave bilgiler verebilmektedir. Biz bu sunuda aynı olguda düşük-evreli astrositomdan yüksek-evreli astrositoma geçişte konvansiyonel, perfüzyon ve spektroskopi MR bulgularını literatür verileriyle birlikte gösterdik. Yüksek-evreli tümörde vasküler proliferasyona bağlı olarak rCBV oranında belirgin yükselme görüldü. MR spektroskopide kolin pikinde ileri derece artma, laktat pikinde orta derecede yükselme ve n-asetil aspartat pikinde ileri derecede azalma izlendi.

Parasellar dermoid cysts are uncommon intracranial lesions. The rupture of a dermoid cyst which typically occurs spontaneously is relatively rare. Here we present the magnetic resonance imaging findings of conventional T1/T2- weighted sequences, fluid attenuated inversion recovery sequence and diffusion-weighted echo planar imaging sequence in ruptured parasellar dermoid cyst with generalized subarachnoid dissemination., Parasellar dermoid kistler sık görülmeyen intrakranial lezyonlardır. Tipik olarak spontan oluşan dermoid kist rüptürü göreceli olarak nadirdir. Biz parasellar yerleşimli, dev boyuta ulaşan ve subaraknoid aralık içine rüptüre olan dermoid kistli bir olgunun konvansiyonel, FLAIR ve difüzyon- ağırlıklı MRG bulgularını sunmaktayız.

Hemifacial spasm (HFS) is unilateral involuntary and painless contractions of the facial muscle innervated by the seventh cranial nerve. It is generally formed by the compression of the root exit zone of the seventh cranial nerve via the neighbourhood artery, due to its vascular dolichoectasia. 3B CISS MR sequences are a necessary imaging method in addition to conventional methods in the evaluation of hemifacial spasm. We aimed to report and discuss the clinical and radiological findings of case with contractions on the left half of his face, having hemifacial spasm due to vertebrobasilar dolichoectasia demonstrated by 3D CISS MRI method., Hemifasiyal spazm (HFS), 7. kranial sinirin innerve ettiği fasiyal kasların tek taraflı istemsiz ve ağrısız kontraksiyonudur. Sıklıkla 7. kranial sinirin bir komşu arter tarafından kök giriş bölgesinde vasküler dolikoektaziye bağlı kompresyonu ile oluşmaktadır. Fasiyal sinirin vasküler patolojiye bağlı kompresyonunu ve diğer kranial sinirleri değerlendirmede 3B CISS MR sekansı, konvansiyonel görüntülere ek olarak yapılması gerekli bir görüntüleme yöntemidir. Bu yazıda, 3B CISS MRG yöntemi ile vertebrobaziler dolikoektazi ve buna bağlı nörovasküler basının gösterildiği hemifasiyal spazmı olan bir olgunun klinik ve radyolojik bulgularını sunmayı ve tartışmayı amaçladık.

The aim of this study was to detect the cranial MR findings in eclampsia and to differentiate cerebral infarction from reversible vasogenic edema by diffusion weighted imaging (DWI). Cranial MR (1,5T; T1-weighted, T2-weighted and/or Fluid Attenuated Inversion Recovery; FLAIR and DWI) was performed in 14 eclamptic patients in order to evaluate the neurological deficits. Bilateral and symmetrical one fields most commonly located in the distribution of the posterior cerebral circulation were detected in all patients except two. DWI performed to differentiate cytotoxic edema from vasogenic edema was normal in 4 (29 %) patients while increased intensity was detected in 10 (71 %) of them. Quantitative apparent diffusion coefficients (ADC) were normal or above in abnormal regions of 9 patients. This was considered as “T2 shine through effect”. ADCs were abnormally low, representing cerebral infarction in one eclamptic patient. As a result, DWI with ADC calculations is a valuable means of differentiating vasogenic edema from cytotoxic one in eclamptic encephalopathy., Bu çalışmada, eklamptik ensefalopati kliniği olan olgularda kranyal MR bulgularının saptanması ve difüzyon ağırlıklı manyetik rezonans (DAMR) görüntüleme ile tedavi seçenekleri farklı olan serebral enfarkt ile ensefalopatiye bağlı geçici vazojenik ödem sahalarının ayırımı amaçlandı. Nörolojik defisit gelişen 14 olguda; kranyal MR incelemesi yapıldı. 1,5 T MR cihazında T1 ağırlıklı (T1A), T2 ağırlıklı (T2A) ve/veya Fluid Attenuated Inversion Recovery (FLAIR) ve DAMR sekansları uygulandı. İki olgu dışında, olguların hepsinde bilateral ve simetrik, posterior dolaşım sulama alanlarında hakim ödem alanları saptandı. Sitotoksik/vazojenik ödem ayırımı için yapılan DAMR inceleme 4 olguda (%29) normal iken, 10 olguda (%71) bu bölgelerde hiperintensite saptandı. Sitotoksik ödem sahalarını temsil edebilecek hiperintens bölgelere yönelik yapılan ölçümlerde, 9 olguda difüzyon katsayılarının normal sınırlarda veya üstünde olduğu saptanarak “T2 shine through” etkisi olarak değerlendirildi. Bir olguda ise serebral enfarktı temsil eden düşük ADC değerleri bulundu. Sonuç olarak, eklamptik ensefalopatide sitotoksik ödem ile geçici vazojenik ödem alanlarının ayırımında DAMR inceleme; ADC haritalarının kullanımıyla birlikte etkili bir yöntemdir.

ÖZET Sarılıklı hastanın değerlendirilmesinde radyolo jisinin rolünde son yıllarda bi'yük değişiklikler olmuştur» Daha önceleri safra yollarının konvansiyonel radyolojik incelenmesi hipotonik duodenograf i, arteriografi gibi in- direkt yöntemlerle veya IV kolan jiograf i gibi oldukça sı nırlı direkt yöntemlerle yapılmaktaydı. Bugün bu yöntem ler, yerlerini büyük ölçüde US ve KT gibi noninvaziv ke- sitsel yöntemlere ve PTK» ERKP gibi invaziv yöntemlere bı rakmıştır. 1974 yılında DK'JRA tarafından Chiba iğnesinin PTK uygulama alanıns sokulması ile cerrahi sarılıkların tanısı ve ayırıcı tanısında büyük gelişmeler olmuştur» Yeni ve non invaziv bir yöntem olan US nin sarılıkla rın tanı ve ayırıcı tanısında rolü iyi bilinmektedir» talışmrmızda cerrahi sa rılıklarda obstrüksiyon düzeyini ve nedenini saptamada PTK ve US nin tanı değerini karşılaştırdık» Çalışmamız 1983-1985 yılları arasında Radyoiı ji na Bilim Dalı'na başvuran 18 ila 80 yaşları arasında 11 erkek ve 14 kadın, toplam 25 olguyu kapsamaktadır.-99- Olgularmızden 11 'i koledok taşı, dokuzu pank reas başı kanseri, üçü ampulla Vateri kanseri, b5ri ko- ledok kisti ve biri de porta hepatis tümörü idi. Olgula rımızın tümüne ultrasonograf i ve 18 ine de PTK yapılmış tır» PTK uygulanan olçularımızdaki kcmplikasyon görülme oranı %596 dır» Ultrasonograf ide 6 koledok taşı ve bir prnkreas beşi krnseri olgusuna yanlış tanı kondu. Diğer tüm olgularımızda ki bulgular ve tanı patoloji ile uyumlu idi» Çalışmamıza gere obstrüksiyon düzeyini saptamada US nin doğruluk oranı %68, sens itivitesi $89«4 ve spesivi- tesi $70.8 dir» PTK nın ise doğruluk oranı %100 dür. Obst rüksiyon düzeyini saptamada US nin doğruluk oranı $68, sensitivitesi $89*4 ve soesivitesi $70,8 dir. PTK nın ise doğruluk orpnı %100 dür» Bu veriler literatürle uvumludur» Sonuç olarak ucuz» uygulanmrsı nın basit her an tekrarlanabilir olması ve noninvaziv özelliklerinden do layı US cerrrhi sarılıkların tanısında ilk seçilecek yöntem olmalıdır» Operasyon endikesyonu olan cerrahi sarılıklı olgularda ve palytif tedavi amaçlı radyolojik girişimsel yöntemlerden önce biiiyer ağacı iyi bir şekilde demonstre etme ve cerraha yol gösterici olma özellisinden dolayı, operasyondan önce PTK uygulamasının vsrnrli olabileceği kanısına varıldı. 114

İç Hastalıkları, hekim adayının kliniğe ilk adım attığı ve hastayla karşılaştığı bölümlerden birisidir ve tıp eğitiminin temel taşlarından birisidir. İyi bir iç hastalıkları bilgisine sahip olan bir hekim, gerek aile hekimi gerekse uzman hekim olarak herhangi bir branşta çalışırken hastalarına daha fazla yardımcı olacaktır. Tıpta, hastalıklara doğru bir teşhis koymak için hekim öncelikle iyi bir anamnez almalıdır. Hasta ile iyi bir iletişim kurulmalıdır. Anamnez teşhisin yarısı olarak kabul edilir. Tıbbi öyküde sadece hastanın yakınmaları ve kronolojik olarak hikayesi değerlendirilmez aynı zamanda ayırt edici tanı yapılmaya çalışılır. Sistem sorgulaması hastanın söyleyemediği ya da unuttuğu şikayetleri saptamamızı sağlar. Sonra sistemik bir fizik muayene yapılarak değerlendirme aşamasına geçilir. İyi bir hekim, daima hastanın klinik yakınma ve bulgularını bir hastalık ile açıklayabilmelidir. Böylece hastaya doğru bir tanı koyarak tedaviye başlayabilir, bazen de tanı için ileri incelemelere ihtiyaç duyar. Laboratuvar ve/veya görüntüleme yöntemlerine başvurur. Bu kitapta iyi bir hekimlik sanatı uygulayabilmeniz için yukarıdaki konularda yeterli düzeyde bilgiye sahip olmanız ve hastalara sistematik olarak yaklaşmanız hedeflenmiştir.

Objective To determine the relationship between arterial distensibility and hypothyroidism by simultaneous assessment of coronary angiography and aortic distensibility, measured using 128-slice retrospective electrocardiogram-gated multiple row detector computed tomography (MDCT). Methods Untreated hypothyroid patients and age-matched euthyroid patients, who underwent 128-slice retrospective electrocardiogram-gated MDCT to evaluate the coronary arteries, were assessed. Intraluminal aortic areas in systolic and diastolic phases of the cardiac cycle were measured with multiphase reformation at predefined locations including the ascending aorta, proximal descending aorta and distal descending aorta in the widest axial plane. Results The study included 21 hypothyroid and 21 euthyroid patients. Patients with hypothyroidism exhibited decreased aortic distensibility between each location in the thoracic aorta (ascending aorta, proximal descending aorta and distal descending aorta) compared with euthryoid patients. Conclusions Hypothyroidism was associated with preclinical vascular alteration, characterized by impaired aortic distensibility at each location of the thoracic aorta, which has been shown to be related to increased cardiovascular risk. Monitoring of aortic distensibility is relevant for evaluating coronary artery disease progression and treatment choices.

The aim of this study was to examine the structural-neurochemical abnormalities of the frontal white matter (FWM), deep gray matter nuclei, and pons in patients with Wilson's disease (WD) using proton magnetic resonance spectroscopy (MRS) and diffusion-weighted imaging (DWI). Nine patients with WD and 14 age-matched controls were examined with MRS. N-Acetylaspartate (NAA), choline (Cho), and creatine (Cr) peaks were calculated. DWI scans from six WD patients and six controls were also obtained. The relative metabolite ratios and apparent diffusion coefficient (ADC) values of the WD patients were compared to those of the control subjects by using statistical measures. Measurements in the thalamus and pons showed significantly lower NAA/Cho and NAA/Cr ratios in the WD group than in the control group (P < 0.05). Thalamic and pontine Cho/Cr ratios in the patient group were significantly higher than those of the control group (P < 0.05). No statistically significant relation was found between the patient and control groups as a result of the MRS examinations of FWM and all ADC measurements (P > 0.05). MRS is a noninvasive, valuable modality for detecting structural-neurochemical changes of the brain stem and deep gray matter in patients with WD. The contribution of DWI in these patients is limited.

Vertebrobasilar junction fenestration is a rare congenital anomaly which is commonly seen with an aneurysm formation. Because of the complex anatomical structure of this area complicates the surgical intervention, endovascular coil treatment of aneurysm is an alternative method. Several fenestration-related aneurysms may not be detected by 2D conventional angiography imaging due to their considerably thin and short structure or small size. By 3D rotational digital subtraction angiography, small-sized fenestrations can be examined at the intended plane from various angles. This method enables us to plan the endovascular intervention in detail by revealing orientation, neck, origin of perforator arteries, and the relation between aneurysm and fenestration. In the present case, we present the angiographic results of the case with vertebrobasilar junction fenestration, along with endovascular treatment of the ruptured aneurysm. Vertebrobasilar bileşke fenestrasyonu nadir bir konjenital anomalidir ve anevrizma formasyonuyla birlikte sıktır. Bu bölgenin kompleks anatomisi nedeniyle cerrahi müdahale zor olduğundan, anevrizmanın endovasküler coil tedavisi alternatif bir metoddur. Bazı fenestrasyonların çok ince ve kısa olması ve bazı anevrizmaların küçük olması nedeniyle iki boyutlu konvansiyonel anjiografi görüntülerinde saptanamayabilir. 3D rotasyonel dijital subtraksiyon angiografi ile küçük boyutlardaki fenestrasyonların ve anevrizmaların istenilen düzlemde, değişik açılarda incelenebilmesi mümkün olmaktadır. Anevrizmanın oryantasyonu, boynu, perforan arterlerin orjini ve anevrizma ile fenestrasyon ilişkisi gösterilerek endovasküler girişimin planmasına olanak sağlar. Biz bu yazıda vertebrobaziler bileşke fenestrasyonlu olgunun anjiografik bulguları ve rüptüre olmuş anevrizmanın endovasküler tedavisini sunmaktayız.

Purpose: To investigate neuronal dysfunction in the thalami of juvenile myoclonic epilepsy (JME) by using proton magnetic resonance spectroscopy (MRS). Methods: We performed single-voxel proton MRS over the right and the left thalami of 15 consecutive patients (10 women, 5 men) with JME (mean age 20.3 years) and 16 healthy volunteers (10 women, 6 men) (mean age 24.5 years). All patients had seizure onset in late childhood-teenage, normal neurologic examination, typical electroencephalogram (EEG) of JME and normal magnetic resonance imaging (MRI). We determined N-acetylaspartate (NAA) values and NAA over creatine-phosphocreatine (Cr) values. Mann-Whitney U-test was used to evaluate group differences. Results: Group analysis showed that echo time (TE) 270 integral value of NAA over left thalamus were significantly decreased in JME patients as compared with controls (34.6033 +/- 15.8386; 48.0362 +/- 22.2407, respectively, P = 0.019). Also group analysis showed that thalami NAA/Cr ratios were significantly decreased in JME patients (right side, 2.21 +/- 1.07; left side 2.00 +/- 0.72) as compared with controls (right side, 3.45 +/- 1.50; left side, 3.08. +/- 1.60; P = 0.011 and P = 0.030, respectively). Conclusion: In the previous studies, NAA values inpatients with JME found that they were not statistically lower in thalami than control group. But, in our study, NAA value was found tow as well. It has been known that NAA is a neuronal marker and hence it is a valuable metabolite in the neuron physiopathology. As a result, in the patients with JME we tried to support the theory that the underlying mechanism of the generalized seizures was the abnormal thalamocortical circuity, determining the thalamic neuronal dysfunction in MRS statistically.

Transient focal lesions of splenium of corpus callosum can be seen as a component of many central nervous system diseases, including antiepileptic drug toxicity. The conventional magnetic resonance (MR) findings of the disease are characteristic and include ovoid lesions with high signal intensity at T2-weighted MRI. Limited information exists about the diffusion-weighted MRI characteristics of these lesions vanishing completely after a period of time. We examined the conventional, FLAIR, and diffusion-weighted MR images of a patient complaining of depressive mood and anxiety disorder after 1 year receiving antiepileptic medication.

Purpose: The aim of our study is to investigate the contribution of DWI, DCE-MRI, ADC measurements and T2 relaxometry in diagnosis of distinguishing cholesteatoma and COM Materials and Methods: Our study is created by retrospectively reviewing MR images of a digital archive of totally 41 patients that were clinically or surgically diagnosed as COM and cholesteatoma. DWI, ADC values, T2 relaxation time, and CEP of lesions between the two groups were compared statistically. CEP was qualitatively evaluated. ROC analysis and McNemar statistics test were performed. Level of significance was determined as p0.05). When the groups were assessed according to the CEP, 13 of the COM cases showed type 1 (progressive heterogeneous enhancement), 2 cases did not show enhancement (type 3) and 6 cases showed type 4 (progressive homogeneous enhancement). Nineteen patients with cholesteatoma showed type 2 (rim-like enhancement), 1 case showed type 4. Statistical analysis of CEP revealed significant differences between types 1 and 2 (p

BACKGROUND/AIM: The limbic system, specifically the hippocampus, plays a key role in controlling the sleep-wake cycle. Changes in these particular structures of the central nervous system have been suggested to be related to obstructive sleep apnea syndrome (OSAS). We hypothesized that reduced hippocampal volume is a risk factor for excessive daytime sleepiness (EDS) in OSAS. PATIENTS AND METHODS: Twenty-two patients with newly diagnosed OSAS and 20 healthy controls were included in the present study. Polysomnography was performed for each participant to determine the presence of OSAS. EDS was defined based on the Epworth sleepiness scale (ESS) score, and patients were grouped as sleepy or non-sleepy according to this score. The hippocampal volume was calculated by MR volumetry using a manual tracing technique. RESULTS: There was no significant difference between groups in demographic variables. The hippocampus was markedly smaller in the OSAS groups than in controls (p < 0.001 Hippocampal volume was negatively correlated with the ESS score (r = - 0.631, p = 0.002). CONCLUSIONS: Our findings suggest that EDS is associated with reduced hippocampal volume in OSAS.

Summary Purpose To compare the diagnostic efficacies of phase-contrast MRI (PC-MRI) and three-dimensional constructive interference in steady-state (3D-CISS) sequence for the detection of spontaneous third ventriculostomy (STV) on the basis of contrast-enhanced MR cisternography (MRC). Patients and methods Eleven obstructive hydrocephalus patients with clinically-radiologically suspected STV and ten controls were examined by PC-MRI, 3D-CISS and MRC. PC-MRI and 3D-CISS sequence were applied to view the third ventricle and basal cisterns. Following injection of 0.5-1 ml intrathecal Gd-DTPA injection, postcontrast MRC images were obtained in three planes. Presence of STV was scored as follows: grade 0, no existence of STV; grade 1, STV present. Results of PC-MRI and 3D-CISS were compared with the MRC findings. Results In PC-MRI, five patients were assessed as grade 0 and six cases grade 1. As a result of 3D-CISS sequence, eight cases were evaluated as grade 0 and three cases grade 1. Based on MRC, nine cases were assessed as grade 0 and two cases grade 1. False positivity was found in four cases by PC-MRI and in one case by 3D-CISS. The sensitivity, specificity and accuracy of PC-MRI and 3D-CISS sequence regarding demonstration of STV, were 100, 100, 56, 89, 64, and 91% respectively. Discussion PC-MRI and 3D-CISS are helpful in confirming the STV. PC-MRI and 3D-CISS should be the first preference. If PC-MRI and 3D-CISS give negative results, then MRC is not required. MRC should be performed on patients who demonstrate suspected STV findings on PC-MRI and 3D-CISS sequences. MRC may prevent false positive results.

Ağır obstrüktif uyku apne sendromlu (OUAS) hastalarda T1 ağırlıklı manyetik rezonans görüntüleme (MRG) ile beyinde olası morfolojik değişikliklerin, sağlıklı grup ile kıyaslanarak değerlendirilmesi amaçlanmıştır.Bu çalışmada polisomnografi testinde, apne-hipopne indeksi (AHİ)>30 olan ağır OUAS'lı olgular ve AHI0.05). Demografik özelliklerden vücut kitle indeksi (body mass index-BMI) ve polisomnografi verilerinden oksijen saturasyonu (SaO2) %90 altında geçen süre (dk), epworth uykululuk ölçeği (Epworth Sleepiness Scale-ESS), AHI, ortalama minimum SaO2 (%), ortalama O2 desatürasyonu (%) ve arousal indeks açısından OUAS'lı hastalar ile kontrol grubu arasında anlamlı farklılık mevcuttu (P30 and normal subjects with AHI0,05). There was statistically significant differance in Body Mass Index (BMI) as a demographic property and polysomnographic features like time elapsed below 90 % oxygen saturation (SaO2) (min), Epworth Sleepiness Scale-ESS, AHI, mean minimum SaO2 (%), mean O2 desaturation (%) and arousal index values between OSAS patients and control group (p>0,05).In conclusion there was no differance in bilateral cerebral and cerebellar gray and white matter segments, cerebrospinal fluid regions and whole brain volume between OSAS patients and control subjects. Findings of our study has shown that even it?s severe, no structural changes occur in the course of OSAS. 68

PURPOSE T1-weighted (T1W) magnetic resonance images with magnetization transfer (MT) are widely used in the evaluation of multiple sclerosis (MS) plaques. We aimed to evaluate the contribution of the subtraction technique with MT in the detection of acute MS plaques. MATERIALS AND METHODS Sixty-four patients during an MS attack were enrolled in the study. Axial T1W spin echo (SE) with MT, axial-sagittal T2W fast SE, axial FLAIR and postcontrast axial T1W SE magnetic resonance imaging sequence with MT were acquired from all patients. The subtraction (postcontrast-precontrast) images were obtained on the workstation. FLAIR and T2W images were used as reference for plaque imaging. Contrast material enhanced plaques were considered as acute plaques. Qualitatively, both subtracted and contrast-enhanced with MT images were evaluated visually. Quantitatively, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. RESULTS A total of 464 plaques were detected on T2W and FLAIR images. Thirty-five acute plaques were detected on both postcontrast MT and subtracted images. Additionally, 66 acute plaques were only detected on subtracted images visually. CNR and SNR values of acute MS plaques were significantly higher on subtracted MT images than on postcontrast MT images (P < 0.001). CONCLUSION The subtraction technique seems to facilitate the detection of acute MS plaques by intensifying the visibility of poorly enhanced plaques without use of high dose contrast medium. We suggest the use of subtraction technique in routine imaging work-up of MS patients with acute attacks.

The aim of this prospective study was to evaluate the value of unenhanced (three-dimensional constructive interference in steady state (3D-CISS)) and contrast-enhanced MR cisternography (CE-MRC) in detecting the localisation of cerebrospinal fluid (CSF) leak in patients with rhinorrhoea. 17 patients with active or suspected CSF rhinorrhoea were included in the study. 3D-CISS sequences in coronal and sagittal planes and fat-suppressed T-1-weighted spin-echo sequences in three planes before and after intrathecal contrast media adminstration were obtained. Images were obtained of the cribriform plate and sphenoid sinus. In addition, high-resolution CT (HRCT) was performed in order to evaluate the bony elements. The leak was present in 9/17 patients with 3D-CISS and 10/17 patients with CE-MRC. The leak from the cribriform plate to the nasal cavity in six patients and from the sphenoid sinus in four patients was nicely shown by CE-MRC. Eight of those patients were surgically treated, but spontaneous regression of the symptoms in two precluded any intervention. The leak localisations shown with CE-MRC were fully compatible with surgical results. The sensitivities of HRCT, 3D-CISS and CE-MRC for showing CSF leakage were 88%, 76% and 100%, respectively. In conclusion, 3D-CISS is a non-invasive and reliable technique, and should be the first-choice method to localise CSF leak. CE-MRC is helpful in conditions when there is no leak or in complicated cases with a positive beta 2-transferrin measurement.

Rationale and Objectives: In this prospective study, we aimed to reveal the efficiency of phase-contrast magnetic resonance imaging (PC-MRI) in the diagnosis of idiopathic normal pressure hydrocephalus (INPH) and prediction of shunt response. Materials and Methods: The study group consisted of 43 patients with INPH diagnosis and 15 asymptomatic age-matched controls. PC-MRI studies were applied on cerebral aqueduct and superior sagittal sinus (SSS) in all the cases. Results: The maximum and mean cerebrospinal fluid (CSF) flow velocities were significantly higher in the INPH patients compared with the controls (P < .05). CSF stroke volume (43.2 +/- 63.8 mu L) and output/min (3921 +/- 5668 mu L) were remarkably higher in the NPH group compared with the control group (3.9 +/- 3.9 mu L, 439 +/- 487 mu L, respectively) (P < .05). Maximum and mean venous velocity values of the INPH patients (maximum, 19.2 +/- 4.3 cm/s; mean, 16 +/- 3.7 cm/s), were lower than those of the control group (maximum, 21.8 +/- 4.6 cm/s; mean, 18.9 +/- 3.9 cm/s) (P < .05). Stroke volume and venous output/min values of INPH patients in SSS, were significantly lower than those of the control group (P .05). Conclusion: The measurement of CSF venous flow velocities with PC-MRI is a noninvasive test that benefits INPH diagnosis, but remains inadequate in prediction of response against shunt treatment.

Rationale and Objective. The aim of this study was to determine the distinctive features of normal-pressure hydrocephalus (NPH) and other dementias on routine T1-weighted and T2-weighted magnetic resonance (MR) images. Also, the contribution of these parameters to the diagnosis and treatment of NPH was investigated. Materials and Methods. Routine MR images were used to investigate the morphologic features (dilatation of Sylvian cisterns, narrowness of convexity sulci, thickness of corpus callosum (TCC), and dilatation of perihippocampal fissures) and the flow void phenomenon (FVP) in patients with idiopathic NPH (INPH) and other dementias. Routine MR images of 18 patients with INPH, 11 with dementias other than INPH, and 20 controls were retrospectively examined. Morphologic features and the FVP were graded subjectively. The TCC was measured quantitatively. Morphologic parameters, the FVP, and the shunt response were assessed using Kruskal-Wallis and Mann-Whitney U tests. Results. The mean FVP score was significantly higher in patients with INPH (2.89 +/- 0.75) than in controls and patients with other dementias (1.1 +/- 0.85 and 1.09 +/- 0.83, respectively) (P < .001). There was significant difference in terms of TCC between patients with INPH (3 +/- 0.7 mm), those with other dementias (1.9 +/- 0.7 mm), and controls (5.2 +/- 0.8 mm) (P < .001). Significant differences in terms of other morphologic features were found between patients with INPH and those with other dementias (P < .05). No significant difference was found between morphologic parameters and the FVP and the outcome of cerebrospinal fluid diversion (P > .05). Conclusions. Intense FVP is a signature of but is not pathognomonic for INPH. The morphologic analysis of MR images can be distinctive for the diagnosis of INPH or dementias other than INPH. Detailed evaluation of morphologic features and the FVP in routine MR workup of dementia will be useful for accurate diagnosis.

In the current study, we aimed to compare the diagnostic efficacies of phase-contrast magnetic resonance imaging (PC-MRI) and three-dimensional constructive interference in steady-state (3D-CISS) sequence over detection of aqueductal stenosis (AS) on the basis of contrast-enhanced magnetic resonance cisternography (MRC). Twenty-five patients with clinically and radiologically suspected AS were examined by PC-MRI, 3D-CISS, and MRC. Axial-sagittal PC-MRI and sagittal 3D-CISS were applied to view the cerebral aqueduct. Following injection of 0.5-1 ml intrathecal gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) injection, postcontrast MRC images were obtained in three planes in early and late phases. Aqueductal patency was scored as follows: grade 0, normal; grade 1, partial narrowing; and grade 2, complete obstruction. Results of PC-MRI and 3D-CISS were compared with the findings of MRC. In PC-MRI, seven cases were assessed as grade 0, 16 cases grade 1, and two cases grade 2. As a result of 3D-CISS sequence, eight cases were evaluated as grade 0, 12 cases grade 1, and five cases grade 2. Based on MRC, nine cases were assessed as grade 0, whereas nine and seven cases were evaluated to be grades 1 and 2, respectively. Five cases that demonstrated partial patency in PC-MRI or 3D-CISS showed complete obstruction by MRC. PC-MRI is helpful in confirming the AS. However, positive flow does not necessarily exclude the existence of AS. 3D-CISS sequence provides excellent cerebrospinal fluid-to-aqueduct contrast, allowing detailed study of the anatomic features of the aqueduct. MRC should be performed on patients who demonstrate suspected AS findings on PC-MRI and/or 3D-CISS sequences.

AIM: To evaluate the value of morphometric analysis and perfusion-weighted magnetic resonance imaging (MRI) in differentiating solitary metastases from high-grade gliomas. MATERIALS AND METHODS: Forty-eight tumours (22 high-grade gliomas and 26 solitary hemispheric metastases) were evaluated using conventional and perfusion-weighted MRI. T2-weighted, gradient-echo, echo-planar sequences were used for perfusion-weighted MRI. Relative cerebral blood volume (rCBV) ratios were calculated by dividing the rCBV of the intratumoural and peritumoural areas with the average CBV value of the normal white matter areas. Morphometric analysis was carried out by proportioning the area of peritumoural oedema to the mass area. Mann-Whitney U test and ROC Curve analysis were applied for statistical analysis. P < 0.05 was accepted as statistically significant. RESULTS: Mean rCBV ratios of intratumoural areas of high-grade gliomas and metastases were 5.02 +/- 2.47 and 4.62 +/- 2.46, respectively. No statistically significant difference was found (p = 0.515). rCBV ratios of peritumoural oedema were 0.89 +/- 0.51 in high-grade gliomas and 0.31 +/- 0.12 in metastases. The difference was statistically significant (p < 0.001). According to the results of morphometric analysis, a statistically significant difference was present between the two tumour types (p < 0.001). CONCLUSION: Measuring the oedema: mass and rCBV ratios of the oedema surrounding the tumour prior to operation in solitary masses proved to be useful for differentiating metastases from high-grade gliomas.

Amaç: Kronik hipertansiyon hastalarının Manyetik Rezonans (MR) spektroskopi, difüzyon MR, T2 relaksometri yöntemleriyle değerlendirerek radyolojik açıdan kronik hipertansiyona bağlı intrakranial olası hasarların belirlenmesi ve kognitif fonksiyonlarının kontrol grubuyla karşılaştırarak analiz edilmesi amaçlanmıştır.Gereç ve Yöntem: Bu çalışmada en az 10 yıldır hipertansiyonu bulunan 21 hasta ve 11 sağlıklı olgu incelendi. Olgulara 1,5 tesla MR cihazında inceleme yapıldı. Aksiyal T2 FSE (TR/TE 5400/99) ağırlıklı görüntüler ile serebral beyaz cevher ve bazal ganglionların değerlendirilmesi yapıldı ve patolojik sinyal elde edilen olgular çalışma dışı bırakıldı. Frontal beyaz cevher ve talamustan tek voksel MR spektroskopi incelemesi yapıldı (TR: 1500, TE:135). NAA, Cho, Cr metabolitlerine ait amplitüd değerleri kantitatif olarak ölçüldü ve NAA/Cho, NAA/ Cr, NAA/Cho+Cr, Cho/Cr oranları hesaplandı. T2 relaksometri aksiyal planda Carr-Purcell-Meiboom-Gill multi spin eko sekansı ile yapıldı. Elde edilen toplam 16 eko sinyalden piksellerin ortalama T2 relaksasyon süreleri ölçüldü. Difüzyon MR görüntüler aksiyal planda single shot eko-planar spin eko sekansı ile elde edildi. Apparent diffusion coefficient (ADC) haritası oluşturularak frontal beyaz cevher, frontal supkortikal alan, talamus ve lentiform nükleuslarda bilateral ölçüm yapılarak ortalamaları alındı. Ayrıca çalışmamızda tüm olgulara nöropsikolojik testler ve uyarılmış potansiyel testleri uygulanarak hastalar kognitif açıdan değerlendirildi. Çalışma verileri analiz edilirken tanımlayıcı istatistiklerde nicel veriler için ortalama ± standart sapma, nitel veriler için frekansları (n) ve yüzdeleri (%) verilmiştir. Normal dağılmayan veri için iki grup karşılaştırmasında Mann-Whitney U testi kullanılmıştır. Kategorik verinin incelenmesinde Pearson Ki-kare testi ve Fisher'in Kesin Ki-kare testi kullanılmıştırBulgular: Difüzyon MR incelemede lentiform nükleuslar düzeyinde ADC değeri hipertansiyon hastalarında 93.4 mm²/snx10-5, kontrol grubunda ise 78.6 mm²/snx10-5 bulundu (p0,05). Nöropsikolojik testler ve uyarılmış potansiyel testlerinde kontrol grubuna göre anormal sonuçlar hipertansiyon hastalarında çok daha fazla oranlardaydı ancak, anlamlı istatistiksel fark saptanmadı(p>0,05).Sonuç: Çalışmamızda kronik hipertansiyon hastalarına, bazal ganglionlar, frontal beyaz cevher ve frontal subkortikal alandan incelemeler yapıldı. Bu düzeylerde difüzyon MR'de ADC değerlerinin, T2 relaksometri yönteminde ise T2 değerinin yüksek olduğu saptandı. Bu sonuç literatür bilgileriyle beraber değerlendirildiğinde interstisyel aralıkta sıvı artışını düşündürmektedir. NAA miktarının kontrol grubundan daha az bulunması kronik hipertansiyon hastalarında nöron kaybıyla açıklanabilir.Anahtar kelime: Kronik Hipertansiyon, Difüzyon MR, T2 relaksometri, MR Spektroskopi SUMMARYPurpose: Radiologically determining the intracranial potential damages related to chronic hypertension in chronic hypertension patients with magnetic resonance (MR) spectroscopy, diffusion MR and T2 relaxometry methods and analyzing their cognitive functions by comparison to the control group.Material and method: In this study, twenty-one patients with hypertension for at least 10 years and 11 healthy phenomenon were examined. Examinations of the cases were performed on 1,5 Tesla MR device. Cerebral white mattes and basal ganglia were evaluated using axial T2 FSE (TR/TE 5400/99) weighted images, and cases with pathological signals were excluded. Single voxel MR spectroscopy was performed on frontal white matter and thalamus (TR: 1500, TE:135). Amplitude values of NAA, Cho, and Cr metabolites were measured quantitatively and NAA/Cho, NAA/ Cr, NAA/Cho+Cr, and Cho/Cr ratios were calculated. T2 relaxometry was performed in axial plan with Carr-Purcell-Meiboom-Gill multi spin echo sequence. The average T2 relaxation periods for the total 16 echo signals obtained were measured. Diffusion MR images ere obtained with single shot echo-planar spin echo sequence in the axial plan. Bilateral measurements of frontal white matter, frontal subcortical region, thalamus and lentiform nuclei were performed after creating apparent diffusion coefficient (ADC) map, and averages were calculated. In addition, neuropsychological tests and evoked potential tests were performed to all cases and patients were evaluated for cognitive skills. When evaluating the study data, mean ± standard deviations were given for quantitative data in the definitive statistics, and frequencies (n) and percentages (%) were given for qualitative data. Mann-Whitney U test was used for comparison of two groups for data without normal distribution. Pearson?s Chi-square test and Fisher?s Chi-square test were used in the examination of categorical data.Findings: In the diffusion MR examination, ADC value in lentiform nuclei level was found as 93.4 mm²/snx10-5 in hypertensive patients and 78.6 mm²/snx10-5 in the control group (p0,05)Conclusion: In our study, chronic hypertensive patients were evaluated as regards their basal ganglia, frontal white matter and frontal subcortical areas. We saw that ADC values in MR and T2 value in T2 relaxometry were high in these levels. When this result is considered together with the information in the literature, fluid increase in the interstitial space is suggested. Finding the amount of NAA lower as compared to the control group may represent the neuronal loss in chronic hypertension patients.Keywords: Chronic Hypertension, Diffusion MR, T2 relaxometry, MR spectroscopy. 52

The objective of this study was to evaluate the role of phase-contrast cine magnetic resonance imaging (PC-MRI) in detecting possible communications between intraventricular arachnoid cysts (IV-ACs) and cerebrospinal fluid (CSF) spaces based on MR cisternography (MRC) comparison. Twenty-one patients with IV-AC were examined by PC-MRI and MRC. In order to determine the communication of IVAC with its neighbouring CSF spaces, PC-MRI was employed. The communication of IV-ACs with the ventricular system was examined on at least two anatomic planes. Precontrast images and PC-MRI were followed by the intrathecal administration of 0.5-1 ml gadopentetate dimeglumine. Early and delayed MRC were then carried out. Results of PC-MRI were compared with findings of MRC (McNemar's test). In seven IV-ACs, no communication was detected by PC-MRI. In 14 IVACs, a pulsatile CSF flow into the IV-ACs was observed. All the IV-ACs, which have been determined as non-communicating (NC) on the PC-MRI, showed NC character on MRC as well. Six cases suggesting a communication on PC-MRI showed no communication on MRC. MRC revealed eight communicating (38%) and 13 NC (62%) IV-ACs among a total of 21 cases. The sensitivity and specificity of PC-MRI imaging in demonstrating the communication between the IV-ACs and the CSF were 100% and 54%, respectively. PC-MRI is an effective method for evaluating NC IV-ACs. In order to decide about the management of IV-ACs, which are communicating according to the PC-MRI, the results should be confirmed with MRC if suspected jet flow is depicted.

Bu prospektif çalışmanın amacı; faz-kontrast sine MR (FK-MR) ve MR sisternografinin (MRS), normal basınçlı hidrosefalinin (NBH) tanı ve tedavisindeki yerini araştırmaktır.Klinik, laboratuvar ve radyolojik veriler ile NBH tanısı konan 43 hasta ve 15 kontrole, FK-MR ve MRS incelemeleri yapıldı. FK-MR ile akuaduktus serebri ve süperior sagittal sinüs'ün (SSS) akım değerleri elde olundu (hız, atım hacmi ve dakikalık debi). İntratekal yolla 1 ml kontrast madde (Gd-DTPA) enjeksiyonu sonrası; 12., 24. ve 48. saatlerde 3 planda T1 ağırlıklı görüntüler (kontrastsız görüntülerin parametrelerinin aynısı ile) elde olundu. Kontrol ve hasta grubundan elde edilen veriler istatistiksel olarak karşılaştırıldı. Ayrıca şant operasyonuna cevap ile FK-MR ve MRS verileri arasındaki ilişki, istatistiksel açıdan analiz edildi.NBH hastalarının; beyin omurilik sıvısı (BOS) hızları (maksimum-ortalama) ve debileri, kontrol olgularından anlamlı ölçüde yüksekti (p0.05). MRS'nin negatif öngörü değeri; % 100 olarak hesaplandı.FK-MR ve MRS; NBH tanısında faydalı olmakla birlikte, şant cevabını tam olarak öngörmede yetersizdir. MRS'nin avantajı; negatif şant cavabını öngörebilmesidir. NBH ön tanılı olgulara; MR incelemeyi takiben, FK-MR ve MRS'nin çalışılmasını öneriyoruz. To investigate the value of phase-contrast MRI (PC-MRI) and MR Cisternography (MRC) for diagnosis normal pressure hydrocephalus (NPH) and prediction of shunt outcome.Fourty three patients with NPH and fifteen controls (aged-matched) underwent PC-MRI and MRC. MRI flow quantification was used to measure aqueductal velocity-stroke volume and superior sagittal sinus (SSS) velocity-stroke volume. After contrast-material injection into the lumbar subarachnoid space; immediate (12 h) and delayed (24, 48 h) post-contrast MRI was carried out utilizing the identical acquisition parameters as those performed in the pre-contrast MRI (T1 weighted images). Results were compared with NPH patients and controls. Also, outcomes of surgery in NPH patients were evaluated with PC-MRI parameters and MRC findings.The aqueductal velocities (maximum-mean) and stroke volume were elevated in NPH group (p0.05).PC-MRI and MRC appear to be useful tests for differentiating NPH from other dementias-hydrocephalus. PC-MRI and MRC could not use in identifying shunt responsive of NPH patients. After conventional MRI, we suggest the use of PC-MRI and MRC in routine imaging work up of NPH patients. 49

Subakut dönem (>3 gün) subaraknoid kanama (SAK) tanısında bilgisayarlı tomografi (BT), T1-ağırlıklı spin eko (SE), T2-ağırlıklı fast spin eko (FSE), fluid attenuated inversion recovery (FLAIR) ve T2-ağırlıklı gradiyent eko (GRE) sekanslarının etkinliğinin değerlendirilmesi amaçlandı. Uludağ Üniversitesi Tıp Fakültesi Radyoloji AnaBilim Dalı’na SAK şüphesi ile gönderilen, 3 -14 gün arasında semptomları olan 14’ü erkek, 13’ü kadın toplam 27 olgu çalışma kapsamında değerlendirildi. Olgulara kontrastsız BT ve MR ile birlikte, serebral dijital subtraksiyon anjiyografi (DSA) incelemeleri yapıldı. Altı ayrı standart lokalizasyonda (interhemisferik fissür, bazal sisternalar, kortikal sulkuslar, sylvian fissür, intraventriküler, intraparenkimal) kanama araştırıldı. Kanama saptanmasında MR sekanslarının BT incelemeye göre etkinliği araştırıldı. Bulguların istatistiksel değerlendirmesi için McNemar testi kullanıldı. Bu teste göre p> 0.05 anlamlı değil, p< 0.05 anlamlı, p< 0.01 belirgin anlamlı kabul edildi. FLAIR sekansı intraventriküler kanama dışında tüm lokalizasyonlarda SAK saptanmasında BT’den istatistiksel anlamlı şekilde üstündü (p< 0.05). FLAIR sekansı, intraventriküler kanama dışında tüm lokalizasyonlarda subakut dönemde SAK’ı saptamakta BT’ye göre üstün olan en duyarlı MR sekansıdır The aim of this study to compare different magnetic resonance (MR) pulse sequences and computed tomography (CT) in the detection of subacute subarachnoid hemorrhage (SAH) in subacute stages. Twenty-seven patients underwent MRI and CT examination who were suspected to have SAH. MRI (1.5-T) pulse sequences comprised spin-echo T1-weighted, fast spin-echo T2-weighted, fluild attenuated inversion recovery (FLAIR), and gradient-echo (GE) T2-weighted images. We aimed to determine the efficacy of MRI pulse sequences relative to CT in diagnosis of hemorrhage at 6 different localizations.Digital substraction angiography (DSA) were performed in all patients. Among all the techniques, FLAIR is the most sensitive one superior to CT in diagnosis of hemorrhage at all localizations except intraventricular hemorrhage. FLAIR is statistically significant indicators of subacute SAH whereas other MRI pulse sequences, and CT scans, are not.

Purpose: The aims of the study are firstly, to determine the difference in diffusion-weighted imaging (DWI) in normal appearing white matter (NAWM) between patients with acute multiple sclerosis (MS) and controls; secondly, to determine whether there is a correlation between EDSS scores and DWI in acute plaques and also NAWM. Materials and method: Out of 50 patients with acute MS attack, 35 patients had active plaques with diffuse or ring enhancement on postcontrast images. Eighteen healthy volunteers constituted the control group. While 26 of 35 had relapsing-remitting, 9 had secondary progressive MS. Apparent diffusion coefficients (ADC) of the active plaques, NAWM at the level of centrum semiovale and occipital horn of lateral ventricle in the patients and NAWM in control group were measured. ADC values of active plaques were compared with WM of the patients and the control group. The relationship of ADC value of active plaques and WM in MS with expanded disability status scale (EDSS) was investigated by using Mann-Whitney U-test. Results: Of 63 plaques totally, 26 and 37 of the active plaques had diffuse and ring enhancement, respectively. There was no statistically significant difference between ADC value of active plaques and EDSS (p > 0.05). However, there was a statistically significant difference between ADC value of WM occipital horn and EDSS (p < 0.05). ADC value of active plaques were higher than WM in both groups (p < 0.001). The difference between ADC value of WM at the centrum semiovale (p < 0.05) and occipital horns (p < 0.001) in patients and controls was statistically significant. There was no statistically significant difference between EDSS scores, ADC value at centrum semiovale and WM around occipital horn and active plaques in subgroups (p > 0.05). Conclusion: Apparently normal tissue in MS patients may show early abnormalities when investigated carefully enough, and there is an even though moderate correlation between EDSS and ADC values and early alterations of ADC value are starting in the occipital white matter along the ventricles. This has to be verified in larger series.

Introduction: Atypical/malignant meningiomas recur more frequently then typical meningiomas. In this study, the contribution of diffusion-weighted MR imaging to the differentiation of atypical/malignant and typical meningiomas and to the determination of histological subtypes of typical meningiomas was investigated. Methods: The study was performed prospectively on 39 patients. The signal intensity of the lesions was evaluated on trace and apparent diffusion coefficient (ADC) images. ADC values were measured in the lesions and peritumoral edema. Student's t-test was used for statistical analysis. P < 0.05 was considered statistically significant. Results: Mean ADC values in atypical/malignant and typical meningiomas were 0.75 +/- 0.21 and 1.17 +/- 0.21, respectively. Mean ADC values for subtypes of typical meningiomas were as follows: meningothelial, 1.09 +/- 0.20; transitional, 1.19 +/- 0.07; fibroblastic, 1.29 +/- 0.28; and angiomatous, 1.48 +/- 0.10. Normal white matter was 0.91 +/- 0.10. ADC values of typical meningiomas and atypical/malignant meningiomas significantly differed (P < 0.001). However, the difference between peritumoral edema ADC values was not significant (P > 0.05). Furthermore, the difference between the subtypes of typical meningiomas and atypical/malignant meningiomas was significant (P < 0.001). Conclusion: Diffusion-weighted MR imaging findings of atypical/malignant meningiomas and typical meningiomas differ. Atypical/malignant meningiomas have lower intratumoral ADC values than typical meningiomas. Mean ADC values for peritumoral edema do not differ between typical and atypical meningiomas.

Polyarteritis nodosa is a multisystem disease primarily involving the small and medium-sized vessels. Prognosis depends on the presence and severity of visceral involvement. Thrombosis and aneurysm formation commonly occur in kidney and gastrointestinal tract. Although hepatic involvement is also common, hepatic aneurysmal rupture with intrahepatic or perihepatic hematoma formation is infrequent. Hemobilia secondary to aneurysmal rupture is a very rare condition. We present a case of polyarteritis nodosa accompanied by hemobilia and intestinal hemorrhage secondary to hepatic and mesenteric aneurysmal rupture.

Astrositik tümörler çoğunlukla düşük-evreden yüksek evreli lezyona dönüşme eğilimi gösterirler. Konvansiyonel manyetik rezonans (MR) bulguları ile bu iki farklı histopatolojik lezyonun ayrımı bazen güç olabilmektedir. Bu durumda tümöral vaskülariteyi dolaylı gösteren perfüzyon MR ve hücresel metabolizmayı ortaya koyan MR spektroskopi bize fonksiyonel ilave bilgiler verebilmektedir. Biz bu sunuda aynı olguda düşük-evreli astrositomdan yüksek-evreli astrositoma geçişte konvansiyonel, perfüzyon ve spektroskopi MR bulgularını literatür verileriyle birlikte gösterdik. Yüksek-evreli tümörde vasküler proliferasyona bağlı olarak rCBV oranında belirgin yükselme görüldü. MR spektroskopide kolin pikinde ileri derece artma, laktat pikinde orta derecede yükselme ve n-asetil aspartat pikinde ileri derecede azalma izlendi. Astrocytic tumors have the propensity to change from low-grade to high-grade lesions. Though, it is sometimes difficult to differentiate the two histopathologic entities with conventional MRI (magnetic resonance imaging) findings only. In such circumstances, perfusion MRI with its ability to demonstrate tumoral vascularity indirectly and MR spectroscopy highlighting cellular metabolism can provide additional information about physiology. In this case, we reported the progression of a low-grade tumor into a high-grade lesion with the conventional and perfusion MRI and also MR spectroscopy findings in the light of the literature. In high-grade tumors, apparently high rCBV ratios were depicted as a result of vascular proliferation. Remarkable increase of the cholin peak, moderate increase of the lactate peak and apparent decrease of the n-acetyl aspartate peak were identified at MR spectroscop.

Introduction To investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors. Methods We retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student's t-test was used for statistical analysis. Results On CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58 +/- 2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02 +/- 1.40 and 4.68 +/- 1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P < 0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve. Conclusion Differentiating meningiomas with atypical conventional MRI findings from malignant intraaxial tumors can be difficult. Calculation of rCBV ratios and construction of signal intensity-time curves may contribute to the differentiation of meningiomas from intraaxial tumors.

In some instances conventional imaging techniques fail to differentiate meningiomas from isolated dural metastasis. This study aimed to evaluate the role of diffusion and perfusion-weighted MRI in differentiating meningiomas and dural metastasis. In this study, 14 metastasis and 26 meningiomas were involved. The imaging characteristics were analyzed using conventional MRI. Diffusion-weighted MRI was performed and ADC values were calculated from the solid components and the peritumoral edema. Perfusion-weighted MRI was performed and relative cerebral blood volume (rCBV) was calculated. Student's t test was used for the statistical analysis. Dural metastasis and meningiomas could not be differentiated by qualitative assessment of conventional and diffusion-weighted MRI. The mean intratumoral and peritumoral ADC values were not statistically significant (p > 0.05). The rCBV ratios for dural metastasis and meningiomas were 4.13 ± 2.32 and 7.32 ± 4.10 respectively and the difference between two was statistically significant (p = 0.003). Peritumoral rCBV ratios for dural metastasis and meningiomas were not statistically significant (p > 0.05). Conventional MRI findings of dural metastasis and meningiomas may overlap in some lesions. In differentiation of these lesions diffusion-weighted MRI yields no further information additional to conventional sequences. Perfusion-weighted MRI can be useful to distinguish these lesions by demonstrating high intratumoral rCBV ratios for meningiomas and low rCBV ratios for metastasis.

Purpose: The goals of this work were to measure the apparent diffusion coefficients (ADCs) for both hippocampus and amygdala of persons diagnosed with temporal lobe epilepsy (TLE) and unilateral hippocampus pathology on magnetic resonance imaging and to evaluate the sensitivity of diffusion-weighted (DW) images in determination of the lateralization of the epileptogenic focus. Methods: Thirteen cases with a TLE diagnosis and 21 healthy subjects were evaluated. Fluid-attenuated inversion recovery and T2W images of TLE cases revealed hippocampal volume loss and signal intensity changes. DW images were obtained by spin-echo echo-planar sequences vertical to the hippocampal axis. Qualitative and quantitative ADCs for left and right hippocampus and the amygdala of the controls and the patients were determined. Hippocampal ADCs were obtained independently at the head, body, and tail levels of the hippocampus. Statistical evaluation was conducted with Kruskal–Wallis and Mann–Whitney U tests. Predictive cutoff levels of hippocampal ADCs for identifying pathologic areas were established through receiver operating characteristic (ROC) curve analysis. Result On conventional images, 5 of 13 cases had right hippocampal pathology, and 8 of 13 cases had left hippocampal pathology. There were no bilateral hippocampal changes in signal intensity and no cases with bilateral atrophy. The amygdala was normal in all patients except one case of hyperintense signals. No statistical differences were found between the hippocampal and amygdaloid ADCs of the control subjects (P > 0.05). However, there was a significant difference between the ADCs for the side with hippocampal pathology and the ADCs for the contralateral side, and the control group (P < 0.001). No statistical difference was detected for the amygdala (P > 0.05). Hippocampal and amygdaloid ADCs of the contralateral lesion and the values of the control group were not statistically significantly different (P > 0.05). ROC curve analysis indicated 136 as the best cutoff level for hippocampal pathology. Conclusion DW trace images are insensitive in lateralization of hippocampal pathology; however, lateralization can be achieved through ADC measurements of the hippocampus. An increase in ADC on the affected side should be considered as indicating pathology. On the other hand, amygdaloid ADC values remain inaccurate.

BACKGROUND AND PURPOSE: The demonstration of communication between arachnoid cysts (ACs) and the adjacent subarachnoid space is a prerequisite for their proper management. CT cisternography (CTC) is the conventional method for functional evaluation of ACs. The sensitivity of MR imaging to CSF flow has been demonstrated, but reports of the clinical usefulness of MR CSF flow techniques in this application are limited. The purpose of our study was to prospectively evaluate the accuracy of MR CSF flow study as an alternative to CTC in this setting. METHODS: MR CSF flow study with retrospective ECG-gated 2D, fast low-angle shot, phase-contrast (PC), cine gradient-echo sequence was performed in 39 patients with an intracranial AC. Results were compared with intraoperative and CTC findings. RESULTS: PC cine MR imaging results were compatible with operative or CTC findings in 36 (92.3%) of 39 patients. Twenty-four cysts were noncommunicating, and 15 were communicating. Three cysts were evaluated as being noncommunicating on PC cine MR imaging (false-negative) but demonstrated contrast enhancement on CTC. No false-positive diagnoses occurred. All cysts regarded as being communicating on PC cine MR imaging were also found to be communicating on both confirmation methods. CONCLUSION: MR CSF flow imaging with a PC cine sequence can be incorporated in the imaging work-up of ACs. This is a reliable alternative to invasive CTC for the functional evaluation of ACs.

Solid and papillary epithelial neoplasm of the pancreas is a very rare low-grade malignant neoplasm with only 126 cases reported in the literature and seen mostly in young female patients. Surgical excision means cure in cases before malignant degeneration developed. Its characteristic findings are typical location in the tail of the pancreas, peripheral capsule formation, hypodensity on CT images, and hyperintense internal signal characteristics on T1-weighted MR images secondary to hemorrhage and accumulation of methemoglobine molecule. These findings are enough for the preoperative diagnosis that may lead to early surgery and cure. We present the CT and MR findings of this very rare neoplasm in a case report.

Objective: Brucellar spondylitis is one of the most serious complications of brucellosis. It should be considered in patients who have back pain and neurologic disorders as well as systemic symptoms and findings in or from endemic areas such as Turkey. This report describes important features of the disease. Methods: Twenty-five patients with brucellar spordylitis were retrospectively evaluated in terms of their clinical, laboratory, and radiologic features and their response to different treatment regimens. Results: The most common symptoms of brucellar spondylitis were back pain, fever, and sweating. Rose Bengal tests were positive in all of these patients. Brucella species was isolated from blood cultures of 8 (32%) patients. Magnetic resonance imaging (MRI) showed that the lumbar segment was the most frequently involved region. Different combination regimens including 2 or 3 antibiotics were used. Combination of tetracycline (especially doxycycline) and streptomycin was the most widely used therapy regimen. Trimethoprim-sulfamethoxazole, ciprofloxacin, ofloxacin, and rifampin were also included in some combination therapies. In this series, the mean duration of antimicrobial therapy was 130 +/- 45.6 days (range, 77-281 days), and 92% of patients received therapy for greater than or equal to 90 days. There were no mortalities in this study. Conclusions: Brucellar spondylitis should be considered in patients with back pain and neurologic disorders as well as systemic symptoms and findings in endemic areas. MR imaging is recommended in suspected cases. The patients can be treated effectively treated with appropriate antibiotic combinations. Follow up is important because relapses can occur.

Parasellar dermoid kistler sık görülmeyen intrakranial lezyonlardır. Tipik olarak spontan oluşan dermoid kist rüptürü göreceli olarak nadirdir. Biz parasellar yerleşimli, dev boyuta ulaşan ve subaraknoid aralık içine rüptüre olan dermoid kistli bir olgunun konvansiyonel, FLAIR ve difüzyon- ağırlıklı MRG bulgularını sunmaktayız. Parasellar dermoid cysts are uncommon intracranial lesions. The rupture of a dermoid cyst which typically occurs spontaneously is relatively rare. Here we present the magnetic resonance imaging findings of conventional T1/T2- weighted sequences, fluid attenuated inversion recovery sequence and diffusion-weighted echo planar imaging sequence in ruptured parasellar dermoid cyst with generalized subarachnoid dissemination.