The comparison of the efficacy of diffusion weighted imaging (DWI) sequences with 3 different T2-weighted sequences in the detection of focal liver lesions.

PURPOSE: In this study we aimed to compare and evaluate the efficacies of the low and high b value diffusion weighted imaging (DWI) sequences with three different T2-weighted (T2W) sequences. MATERIALS AND METHODS: 255 liver lesions of 147 patients who had undergone MR examinations of the upper abdomen were evaluated. A maximum number of 4 lesions was taken for consideration in patients with multiple lesions. Low and high b valued DWI and 3 different T2W sequences (SSFSE, FIESTA, and PROPELLER FSE) were utilized. The evaluations were done by 3 different radiologists, by utilizing the double blind principle. RESULTS: The lesion detection performances of the b 0 DWI, b 600 DWI, FIESTA T2W, SSFSE T2W, and PROPELLER FSE T2W sequences, were 95.7 %, 66.3 %, 94.4 %, 92.8 %, and 93.8 %, in sequence order. The high b value DWI sequence was able to detect malignant lesions with a higher accuracy rate than the T2W sequences. There was a moderate to high rate of agreement among the interpreters, and the lesion-detection rates of the interpreters were in line with their levels of expertise. CONCLUSION: Even though the higher lesion detection rates of the DWI sequences were not found to be statistically significant, it was concluded that making the evaluations with the addition of DWI to the imaging protocol would certainly decrease the lesion-missing rate, and it would be wise to utilize the DWI technique in routine liver MR imaging.

Evaluation of Brain Volume Changes by Magnetic Resonance Imaging in Obstructive Sleep Apnea Syndrome.

BACKGROUND AND OBJECTIVES: The objective of this study was to evaluate potential morphological changes in the brain tissue of patients with severe obstructive sleep apnea syndrome (OSAS) in comparison with normal subjects by using T1-weighted magnetic resonance imaging (MRI) technique. MATERIAL AND METHODS: This study comprised subjects with severe OSAS with an apnea-hypopnea index (AHI) more than 30 and normal subjects with AHI less than 5 according to polysomnography findings. The study subjects were evaluated using Three Dimensional Magnetization Prepared Rapid Acquisition Gradient Echo sequence on T1-weighted MRI. FreeSurfer morphometric procedure was used as the automated segmentation method and in both cerebral and cerebellar hemsipheres and segmental volumes of brain were analyzed. RESULTS: Of the 22 patients with severe OSAS, 19 were male, three were female and their ages ranged between 40 and 60 years (mean age 50.27 ± 5.3 years). Of the 22 control subjects 19 were male, three were female and their ages ranged between 40 and 60 years (mean age 49.36 ± 6.95 years). There were no statistically significant differences in terms of age and sex properties between the groups. There was a statistically significant difference in BMI between the OSAS patients and the control group. There were statistically significant differences in polysomnographic features (time elapsed below 90% SaO2 (min), Epworth Sleepiness Scale, AHI, mean minimum SaO2 (%), mean O2 desaturation (%), and arousal index values) between the OSAS patients and the control group. CONCLUSIONS: The findings of our study indicated that even if severe, no structural changes occur in the course of mild, moderate, and severe OSAS.

Magnetic resonance imaging evaluation of shoulder joint in patients with early stage of ankylosing spondylitis: A case-control study.

PURPOSE: The goal of this prospective study was to determine the prevalence of shoulder abnormalities on magnetic resonance imaging (MRI) in patients with ankylosing spondylitis (AS) who have normal shoulder X-ray examinations and no clinical shoulder abnormalities using a case-control study. MATERIALS AND METHODS: Fifty-three patients with AS according to the SpondyloArthritis international Society (ASAS) criteria were enrolled in the study. Fifty-three patients with no AS served as control subjects. Shoulder MRI examinations of patients in the two groups were analyzed and results were compared. RESULTS: In the patient group, 26/53 patients (49.1%) demonstrated one or two of the defined pathological shoulder MRI findings, whereas 5/53 patients (9.4%) had similar findings in the control group. In the patient group, 11/53 patients (20.8%) had enthesal bone marrow edema, 19/53 patients (35.8%) had increased synovial fluid, 8/53 patients (15.1%) had tendinitis, and 2/53 patients (3.8%) had bursitis. There was statistically significant difference between the patient and control groups in terms of prevalence of enthesal bone marrow edema, increase in synovial fluid, and tendinitis. CONCLUSION: Shoulder involvement is often overlooked in AS. Knowledge of the early-stage findings of the shoulder involvement due to AS is important to establish an early diagnosis and select treatment options.

Doppler ultrasonography helps discriminate between cirrhotic and non-cirrhotic patients with viral B and C hepatitis.

OBJECTIVE: The aim of this study was to define the cutoff values between compensated cirrhosis and non-cirrhotic patients with viral hepatitis B and C, using the criteria of the Doppler parameters of liver vascularity. MATERIALS AND METHODS: Seventy non-cirrhotic patients with viral hepatitis B and C and 30 cirrhotic patients were included in this prospective study. The diagnostic decisiveness properties of the Doppler values in the pre-determination of liver cirrhosis were evaluated using receiver operating characteristics curve analysis. RESULTS: Taking the cutoff value for hepatic vein waveform index as 0.605, a sensitivity of 80% and a specificity of 77.1% were obtained. The sensitivity was 80%, and the specificity was 68.6% for a mean max portal velocity cutoff value of 18.25cm/s. When the hepatic artery resistivity index cutoff value was taken as 0.705 for the diagnosis of cirrhosis, the sensitivity was 82.5% and the specificity 72.1%. For a hepatic artery pulsatility index cutoff value of 1.295, a sensitivity of 82.5% and a specificity of 72.1% were found. CONCLUSION: It is not possible to diagnose cirrhosis with only hemodynamic changes. However, the cutoff values may be helpful in the selection of patients to undergo the procedure of liver biopsy.