Semiquantitative strain elastography of liver masses.

OBJECTIVES: This study was designed to determine the utility of semiquantitative strain elastography in differential diagnosis of solid liver masses. METHODS: A total of 103 patients with focal liver masses underwent abdominal sonographic examinations and freehand elastography of focal hepatic lesions. Eighty-two patients (79.7%) with 93 focal hepatic lesions were included in the study. Twenty-one patients (20.3%) were excluded from the study because of technical limitations of semi-quantitative strain elastography and difficulty in detection of normal liver parenchyma on gray-scale sonography. We evaluated different focal hepatic lesions such as hemangiomas, focal nodular hyperplasia, nodular regenerative hyperplasia, adenomas, hepatocellular carcinomas, metastases, and cholangiocarcinomas. The stiffness of the lesions was determined by measurement of strain values on semiquantitative strain elastography. The strain index value (strain ratio of liver parenchyma and focal lesions) of each lesion was calculated. Mean strain index values of benign and malignant liver lesions were compared. RESULTS: The mean strain index value of malignant liver lesions ± SD (2.82 ± 1.82) was significantly higher than that of benign liver lesions (1.45 ± 1.28; P< .0001). Hemangiomas had a significantly lower mean strain index value than other benign lesions (P < .0034). There was no statistically significant difference between strain index values of different types of malignant lesions (P > .05). CONCLUSIONS: Semiquantitative strain elastography may be helpful for differentiating benign and malignant liver masses. The substantial overlap between strain index values of benign and malignant liver masses limits clinical usefulness of this technique.

Role of the apparent diffusion coefficient in the differential diagnosis of gastric wall thickening.

PURPOSE: To evaluate the role of the apparent diffusion coefficient (ADC) measurement made using diffusion-weighted magnetic resonance imaging (DWMRI) in the differential diagnosis of benign and malignant gastric wall thickening. MATERIALS AND METHODS: Axial T2-weighted and DWMRI at b 600 and b 1000 s/mm(2) gradients were performed in 94 patients (44 patients with gastric malignancy and 50 patients with benign gastric diseases) with gastric wall thickening which was detected by multidetector computed tomography (MDCT). The ADC values of the gastric lesions and healthy gastric walls in patients with gastric malignancies and in patients with benign gastric diseases were used in the differential diagnosis of benign and malignant lesions of the stomach. RESULTS: The mean ADC values were lower in patients with gastric malignancies (1.62 ± 0.57 and 1.40 ± 0.33 at b 600 and b 1000, respectively) compared to those with healthy gastric walls (2.95 ± 0.59 and 2.18 ± 0.48) and benign gastric diseases (3.08 ± 0.52 and 2.34 ± 0.42) at b 600 and b 1000 gradients (P < 0.0001). CONCLUSION: The ADC measurement on DWMRI may be used to differentiate between benign and malignant gastric diseases.

Diffusion-weighted MRI of fatty liver.

PURPOSE: To investigate the effect of fat infiltration on the apparent diffusion coefficient (ADC) of liver, and assess the relationship between ADC and hepatic fat fraction (HFF). MATERIALS AND METHODS: MRI scans of 120 consecutive patients were included in this retrospective study. Of these, 42 patients were included in the fatty liver group and 78 in the control group. ADC values were measured from a pair of diffusion-weighted (DW) images (b = 0 mm(2) /s and 1000 mm(2) /s). HFFs were measured using T1W GRE dual-echo images. The difference between the ADCs of the two groups was assessed with the t-test. The relationship between HFF and ADC was determined using linear regression analysis and the Pearson correlation coefficient (r). RESULTS: Mean HFFs were 0.85 ± 2.86 and 13.67 ± 8.62 in the control and fatty liver groups, respectively. The mean ADC of fatty liver group 1.20 ± 0.22 × 10(-3) mm(2) /s was significantly lower than that of the control group 1.32 ± 0.23 × 10(-3) mm(2) /s (P = 0.02). Linear regression analysis revealed an inverse relationship between ADC and HFF (r = -0.39, P < 0.0001). CONCLUSION: ADC significantly decreases in patients with >5% HFF, and ADC and HFF exhibit an inverse relationship.

Diagnosis of Peritoneal Metastases with Abdominal Malignancies: Role of ADC Measurement on Diffusion Weighted MRI.

OBJECTIVE: The purpose of our study was to evaluate the utility of the apparent diffusion coefficient (ADC) value measurement in the diagnosis of peritoneal metastases on diffusion weighted magnetic resonance imaging. MATERIALS AND METHODS: Diffusion weighted imaging with conventional magnetic resonance imaging sequences was performed on twenty consecutive oncology patients (group I) with peritoneal metastases. The ADC values of the metastases, the peritoneal fat around the metastases (group I) and the peritoneal fat in patients with no malignancy (group II) at b(0-100), b(0-600), and (b 0-1000) s/mm(2) gradients were measured and compared. RESULTS: The apparent diffusion coefficient values of three gradients in peritoneal metastases (2.27±0.4; 1.67±0.7 and 1.09±0.4×10(-3) mm(2)/s at b 100, 600 and 1000 gradients, respectively) were significantly lower than the ADC values of the peritoneal fat around metastases (3.07±0.4; 2.07±0.4; 1.33±0.3×10(-3) mm(2)/s at b 100, 600 and 1000 gradients, respectively) (p<0.05). There was no significant difference between the ADC values of peritoneal fat in the patients of group I and group II at the 3 diffusion gradients (p>0.05). CONCLUSION: The measurement of ADC values may be used as a complementary diagnostic method in differentiating peritoneal metastases from peritoneal fat on Diffusion Weighted MRI (DWMRI DWMRI).

Diffusion-weighted MR imaging of thyroid nodules.

INTRODUCTION: The purpose of our study was to determine the diagnostic role of diffusion-weighted imaging (DWI) in the differentiating of malignant and benign thyroid nodules by using fine needle aspiration biopsy cytology criteria as a reference standard. The apparent diffusion coefficient (ADC) values of the normal-looking thyroid parenchyma were also evaluated both in normal patients and in patients with nodules. METHODS: Between March 2007 and February 2008, 76 consecutive patients with ultrasound-diagnosed thyroid nodules and 20 healthy subjects underwent diffusion-weighted MR imaging by using single-shot spin echo, echo planar imaging. A total of 93 nodules were included in the study using the following b factors 100, 200, and 300 mm(2)/s. ADC values of thyroid nodules and normal area in all subjects were calculated and compared using suitable statistical analysis. RESULTS: Mean ADC values for malignant and benign nodules were 0.96+/-0.65 x 10(-3) and 3.06+/-0.71 x 10(-3)mm(2)/s for b-100 factor, 0.56+/-0.43 x 10(-3) and 1.80+/-0.60 x 10(-3)mm(2)/s for b-200, and 0.30+/-0.20 x 10(-3) and 1.15+/-0.43 x 10(-3)mm(2)/s, for b-300, respectively. Mean ADC values of malignant nodules were lower than benign nodules. There were significant differences in ADC values between benign and malignant nodules. ADC values among normal-appearing thyroid parenchyma of patients and normal-appearing thyroid parenchyma of healthy subjects were insignificant at all b factors. CONCLUSION: Benign nodules have higher ADC values than malignant ones. DWI may be helpful in differentiating malign and benign thyroid nodules.

Age-related metabolic changes in the corpus callosum: assessment with MR spectroscopy.

PURPOSE: The aim of this study was to examine metabolite changes in different parts of the corpus callosum (CC), and to relate these changes to different age groups using magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: A total of 76 healthy subjects participated in the study with MRS analyses (39 females and 37 males). Subjects were grouped by age into four groups, in increasing order: Groups 1, 2, 3, and 4. Single-section 2D multivoxel spectroscopy was performed using chemical-shift imaging techniques. The voxels were placed on the rostrum, genu, corpus, and splenium of the CC. Peak metabolite ratios of N-acetylaspartate (NAA)/choline (Cho), NAA/creatine (Cr), and Cho/Cr were calculated from the rostrum, genu, body, and splenium. One way analysis of variance test was performed for the detection of changes in different age groups. Pearson correlation test was performed for correlation of metabolite ratio related to age. RESULTS: Statistically significant differences were found for NAA/Cho ratios for the rostrum, corpus, and splenium, and NAA/Cr ratios for the corpus and splenium between Groups 1 and 2, Groups 1 and 3, and Groups 1 and 4. Metabolite ratios of the corpus and splenium were similar. This similarity was also valid for parts of the rostrum and genu. CONCLUSION: Metabolite ratios in the CC are influenced by age. Age-related changes and regional metabolite levels may cause these alterations. Analyses of the CC may be informative for the evaluation of white matter. MRS may help to demonstrate metabolite levels and ratios of the CC.

Evaluation of the effects of sildenafil citrate (viagra) on vertebral artery blood flow in patients with vertebro-basilar insufficiency.

OBJECTIVE: To investigate the effects of sildenafil citrate (Viagra) on the vertebral artery blood flow of patients with vertebro-basilar insufficiency (VBI) using color duplex sonography (CDS). MATERIALS AND METHODS: The study included 21 patients with VBI (aged 31-76; mean 61.0 +/- 10.5 yrs). We administered a 50 mg oral dose of sildenafil citrate to all patients. Next, we measured the peak systolic velocity (Vmax), end diastolic velocity (Vmin), resistive index (RI), pulsatility index (PI), diameter, area, and flow volume (FV) of vertebral arteries using CDS before the administration of sildenafil citrate; 45 minutes after, and 75 minutes after administration. Statistical testing was performed using SPSS for windows version 11.0. The statistical test used to determine the outcome of the analysis was the repeated measures analysis of variance (ANOVA) test. RESULTS: Compared to the baseline values, the vertebral artery diameter, area, and FV increased significantly following the administration of sildenafil citrate. The diameter, area and FV increased from 3.39 mm at 45 minutes to 3.64 mm at 75 minutes, 9.43 cm(2) to 10.80 cm(2) at 45 minutes and 10.81 cm(2) at 75 minutes, as well as from 0.07 L/min at baseline to 0.09 L/min at 45 minutes and unchanged at 75 minutes, respectively. CONCLUSION: Sildenafil citrate elicited a significant effect on vertebral artery diameter, area and FVs.

Isolated congenital absence of the pericardium.

Absence of the pericardium can vary from partial to complete absence. Patients with complete absence of the pericardium are either asymptomatic or have nonspecific chest pain, and no treatment is needed. Patients with partial absence of the pericardium are at risk for possible symptomatic herniation of the left atrial appendage or left ventricle, leading to fatal myocardial strangulation. Therefore, it is very important to differentiate partial from complete absence of the pericardium. A 7-year-old girl presented with isolated congenital absence of the pericardium, which generally has a good prognosis. It is a relatively asymptomatic anomaly that usually requires no treatment. Some cases involve complications that require operative treatment. Absence of the pericardium can be precisely defined by computed tomography and magnetic resonance imaging.

Cingulate gyrus volumetry in drug free bipolar patients and patients treated with valproate or valproate and quetiapine.

In patients with bipolar disorder, recent brain imaging studies have reported cingulate cortex volume change. We performed a volumetric magnetic resonance imaging (MRI) study to assess the subregions of the cingulate gyrus; left anterior cingulate (LAC), left posterior cingulate (LPC), right anterior cingulate (RAC), and right posterior cingulate (RPC). Our sample consisted of bipolar patients that are either unmedicated (n=10), on valproate monotherapy (n=10) or on valproate plus quetiapine (n=10) versus healthy comparisons (n=10). Thirty right-handed bipolar disordered patients were recruited. Of them, 10 were first-applying patients who never had taken any drug for this condition (medication-naive group), 10 were on valproate treatment (valproate group) and 10 were on valproate plus quetiapine treatment (valproate plus quetiapine group). Cingulate gyrus volumes included both cortex and white matter. Drug-free patients had significantly smaller LAC and LPC volumes compared with valproate and valproate plus quetiapine groups and healthy controls. In addition, in post hoc comparisons, a trend toward significant difference was found between valproate plus quetiapine group and valproate group in regard to only LAC. Our findings suggest that valproate and quetiapine may have neuroprotective effects.

Hippocampal 1H MRS in patients with bipolar disorder taking valproate versus valproate plus quetiapine.

BACKGROUND: No study to date has examined the effects of mood stabilizer alone and the combination of mood stabilizer and atypical antipsychotic, quetiapine, on hippocampal neurochemical markers of bipolar disordered patients concurrently. We therefore undertook a proton magnetic resonance spectroscopy (1H MRS) study of drug-free patients with bipolar disorder (drug-free group), patients undergoing valproate treatment (valproate group), patients administered valproate+quetiapine (valprote+quetiapine group) and healthy controls, focusing on the in vivo neuroanatomy of the hippocampus. METHOD: Thirty patients from the Firat University School of Medicine Department of Psychiatry and 10 healthy controls gave written informed consent to participate in the study. The patients and controls underwent proton magnetic resonance spectroscopic imaging (1H MRSI), and measures of N-acetylaspartate (NAA), choline-containing compounds (CHO), and creatine+phosphocreatine (CRE) in hippocampal regions were obtained. RESULTS: The drug-free patients had significantly lower NAA/CRE and NAA/CHO ratios compared with the valproate and valproate+quetiapine groups and the healthy controls. The lower NAA/CRE and NAA/CHO ratios remained statistically significant even after covarying for age or whole brain volume compared with the valproate and valproate+quetiapine groups and healthy controls. In post hoc comparisons, a significant difference was found between the valproate+quetiapine group and the valproate group only with regard to NAA/CHO. CONCLUSION: Our findings suggest that valproate has a neuroprotective effect. In post hoc comparisons, a significant difference was found between the valproate+quetiapine and the valproate group with regard to NAA/CHO, indicating that the addition of quetiapine further increases the level of NAA and provides an additional neuroprotective effect.

Effects of overweight on luminal diameter, flow velocity and intima-media thickness of carotid arteries.

PURPOSE: To the best of our knowledge, there are only a few previous studies on the effects of overweight on extracranial carotid arteries. We aimed to investigate the effects of overweight on flow velocities, luminal diameters and intima media thicknesses (IMTs) of the common and internal carotid arteries (CCA, ICA). MATERIALS AND METHODS: A prospective study on color duplex sonography of the extracranial arteries was performed in 71 adults, ages between 25-58 years old. The body mass index (BMI) was found to be normal in 24 (group 1) and high in 47 (group 2) subjects of the study group. Flow velocity (FV), luminal diameter and IMT of carotid arteries of all the participants were measured. RESULTS: There were significant differences between group 1 and group 2 in the following parameters; luminal diameters of the right CCAs were significantly larger in group 2, peak-systolic FV of ICAs were significantly lower in group 2 than in group 1 and ICA end-diastolic FVs were significantly lower in group 2 than in group 1. CONCLUSION: The present data shows that there is a correlation among carotid artery luminal diameter, FVs and overweight. In the overweight subjects, the increased luminal diameter and decreased FVs can point at the early stage of atherosclerosis. The influence of adiposity on atherosclerosis is very complex and varies with gender and age, therefore we need larger series and further investigation.

Hippocampal 1H MRS in first-episode bipolar I patients.

Based on earlier structural and functional neuroimaging studies, we specifically wanted to assess N-acetylaspartate (NAA), choline-containing compounds (CHO), and creatine+phosphocreatine (CRE) levels in brain hippocampus previously demonstrated to be involved in the pathophysiology of bipolar disorder which have not been evaluated in first-episode patients. Twelve patients meeting DSM-IV criteria for bipolar disorder who consecutively applied to our department and 12 healthy controls were studied. The patients and controls underwent proton magnetic resonance spectroscopy ((1)H MRS), and measures of NAA, CHO, and CRE in hippocampal regions were obtained. ANOVA revealed in the hippocampus a significant effect of diagnosis for NAA/CRE and for NAA/CHO but not for CHO/CRE. Post hoc analysis showed that patients had a significant bilateral reduction of NAA/CRE and of NAA/CHO. No significant correlation was found between hippocampus volume and ratio measures. Correlation analyses exhibited significant correlation between NAA values and the YMRS for both side of the hippocampus, but not any other clinical variables (age, age at onset, and duration of illness). In summary, hippocampal neuronal abnormalities seem to be present at the onset of bipolar I disorder. These data suggest that neuronal abnormalities in hippocampus may be associated with the severity of bipolar I disorder. As these data were obtained in patients in their first-episode (all the patients were manic), they cannot be explained by chronicity of illness or pharmacological treatment.

Sonographic evaluation of plantar fasciitis and relation to body mass index.

PURPOSE: We have investigated the role of sonography in the diagnosis of plantar fasciitis. MATERIALS AND METHODS: This study evaluates 39 patients with plantar fasciitis and control group of 22 healthy volunteers. The plantar fascia thickness was measured 5 mm distal to the insertion of the calcaneus of plantar aponeurosis. Qualitative parameters such as decreased echogenity, biconvexity, perifascial fluid and calcification of plantar fascia were also noted. RESULTS: Mean plantar fascia thickness was measured 2.9 mm in patients with unilateral heel pain, 2.2 mm for contralateral normal heel and 2.5mm for control group. There was a statistically significant difference between heel with plantar fasciitis, contralateral normal heel and control groups (p=0.009 and 0.0001, respectively). Mean body mass index was 28 kg/m(2) in patients with heel pain and 25 kg/m2 in control group. Body mass index measurements were significantly different between plantar fasciitis and control groups. We found reduced plantar fascia echogenity in 16 cases (41%), calcaneal spur in 20 cases (51%), biconvex appearance in two cases (5.1%) and perifascial fluid in one case (2.5%). CONCLUSION: We conclude that in patients with plantar fasciitis, ultrasound may detect relatively small differences in plantar fascia thickness even in clinically unequivocal plantar fasciitis.

Effects of sildenafil on major arterial blood flow using duplex sonography.

PURPOSE: Erectile dysfunction (ED) is the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Oral use of sildenafil citrate is effective in the treatment of ED. Although the effects of sildenafil citrate have been investigated in several systems, its effect on aortic, superior mesenteric (SMA), and carotid artery blood flow is still unclear. The aim of this study is to investigate the early phase effects of sildenafil citrate on aortic, SMA, and carotid artery blood flow using color duplex sonography (CDS). METHODS: Thirty-four patients with ED (aged 19-71) were included in this study. Peak systolic velocity, end diastolic velocity, and resistance index (RI) in aorta, SMA, and bilateral common and internal carotid arteries were measured at baseline and 45-75 minutes after the administration of sildenafil citrate using CDS. RESULTS: Statistically significant changes were observed in only 3 of 18 parameters: an increase in post drug values of bilateral internal carotid artery peak systolic velocity (Vmax) compared to baseline values and a significant decrease in the RI value of the left main carotid artery after drug administration compared to baseline values. CONCLUSIONS: Sildenafil citrate had no significant effect on aortic and SMA circulation and only caused mild changes in the carotid artery circulation. Although these alterations may be considered clinically insignificant, further studies assessing long-term effects of sildenafil are warranted.

Measuring resistance index in patients with BPH and lower urinary tract symptoms.

PURPOSE: To assess the correlation between resistance index (RI) measured in different zones of the prostate and other more commonly used parameters of benign prostatic hyperplasia (BPH). METHODS: Twenty-six male patients who underwent a detailed evaluation for lower urinary tract symptoms suggestive of BPH were examined with transrectal (TRUS) color Doppler sonography (CDS). The correlation between RI in various prostate zones, and various urinary flow rates, and the International Prostate Symptom Score (IPSS), and prostatic volume measured by TRUS was determined. RESULTS: No significant difference in RI was observed between right and left transition (TZ) and peripheral zones (PZ) in the prostate (P > 0.05). There was a significant correlation between mean RI and maximum urinary flow rate (Qmax) and mean RI in both zones (r = -0.48 for TZ and r = -0.39, P < 0.05 for PZ). Individual measurements in left and right TZ RI were also correlated with Qmax. There was a correlation between prostatic volume and both the right (P < 0.05, r = 0.56) and the left (P < 0.05, r = 0.58) TZ RI, respectively. CONCLUSION: Our results demonstrate the potential value of RI measurement in the evaluation of patients with lower urinary tract symptoms suggestive of BPH.

Classification of the frequency of carotid artery stenosis with MLP and RBF neural networks in patients with coroner artery disease.

For the classification of left and right Internal Carotid Arteries (ICA) stenosis, Doppler signals have been received from the patients with coroner arteries stenosis by using 6.2-8.4 MHz linear transducer. To be able to classify the data obtained from LICA and RICA in artificial intelligence, MLP and RBF neural networks were used. The number of obstructed veins from the coroner angiography, intimal thickness, and plaque formation from the power Doppler US and resistive index values were used as the input data for the neural networks. Our findings demonstrated that 87.5% correct classification rate was obtained from MLP neural network and 80% correct classification rate was obtained from RBF neural network. MLP neural network has classified more successfully when compared with RBF neural network.

Classification of MCA stenosis in diabetes by MLP and RBF neural network.

For the classification of Middle Cerebral Artery (MCA) stenosis, Doppler signals have been received from the diabetes and control group by using 2 MHz Transcranial Doppler. After the Fast Fourier Transform (FFT) analyses of the Doppler signals, Power Spectrum Density (PSD) estimations have been made and Multilayer Perceptron (MLP) and Radial Basis Function (RBF) have been dealt to apply to the neural networks. PSD estimations of Doppler signals received from MCA of 104 subjects have been successfully classified by MLP (correct classification = 94.2%) and RBF (correct classification = 88.4%) neural network. As we have seen in the area under ROC curve (AUC), MLP neural network (AUC = 0.934) has classified more successfully when compared with RBF neural network (AUC = 0.873).

[Biochemical and immunological effects of ionizing radiation in radiology staff members]. / Iyonizan radyasyonun radyoloji çalisanlarinin bagisiklik düzeyleri ve kan biyokimyasi üzerine etkileri.

PURPOSE: This study aimed to investigate the influence of occupational exposures to long term low-dose ionizing radiation on blood biochemistry and immunity levels of the radiology staff. MATERIALS AND METHODS: Fifty-one subjects, aged between 21-57 years (30.06+/-7.02 years), working in the department of radiology were enrolled to this study. Twenty-five subjects (49.1%) were female and 26 (50.9%) were male. Control group consisted of 40 healthy non-smoking subjects aged between 20-60 years (mean 31.5+/-5.75) who had never been exposed to radiation; 19 (47.5%) of these were female and 21 (52.5%) male. Venous blood samples were obtained from the radiology staff and control group and immunological and biochemical analysis of samples were performed. RESULTS: CD4+ T-lymphocyte ratio, and serum total IgA, IgG, IgM and C3, C4 levels were lower in the radiology staff compared to the controls. Serum triglycerides and paraoxonase activities were increased in the radiology staff (p<0.05). CONCLUSION: In radiology workers exposed to long-term low-dose ionizing radiation, levels of the CD4+ T lymphocytes, total immunoglobulins (IgA, IgG, IgM), C3 and C4 levels were lower, while serum trygliceride levels and paraoxonase activities were significantly higher (p<0.05). IgA and IgM levels of smoker radiology workers were significantly lower than non-smoker radiology workers (p<0.05). Since the staff members of department of radiology are vulnerable to the side effects in parallel to the dose of radiation being exposed, we think that in addition to avoiding radiation as much as possible, they should have periodical blood biochemistry and immune function tests.

[Uterine arteriovenous malformation: US, color Doppler US and MRI findings (case report)]. / Uterin arteryovenöz malformasyon: US, renkli Doppler US ve MRG bulgulari.

Uterine arteriovenous malformations are rare but life threatening lesions. Sixty nine-year old, multiparous, postmenopausal patient complained of intermittent vaginal hemorrhage for 4 years. Serum beta-HCG level of the patient who had no history of uterine curettage or pelvic operation was normal. Noninvasive diagnosis of arteriovenous malformations with congenital or acquired etiology can be made by color Doppler ultrasonography and MRI.

[Pictorial essay: Pneumocephalus]. / Pnömosefali.

Imaging in pneumocephalus aids in the diagnosis and management of this condition, which usually results from trauma, iatrogenic causes, infections, tumors, and cranium abnormalities. The role of computed tomography and magnetic resonance imaging is especially addressed in this article.