Evaluation of cognitive functions of juvenile myoclonic epileptic patients by magnetic resonance spectroscopy and neuropsychiatric cognitive tests concurrently.

Our aim in this research is investigating the hypothesis of biochemical changes in frontal cortex and thalamocortical pathways in juvenile myoclonic epilepsy (JME) and the interaction between the biochemical changes and cortical functions. Magnetic resonance spectroscopy (MRS) was applied to 20 JME patients and 20 controls for measuring N-acetyl aspartate (NAA), N-acetyl aspartate to creatine ratio (NAA/Cr), Glutamine and Glutamate (GLX), Glutamine-Glutamate to creatine (GLX/Cr), Choline containing compounds (Cho) and Choline to creatine (Cho/Cr) levels. Neuropsychological cognitive tests for linguistic and visual attention, linguistic and visual memory, visuospatial and executive functions were applied to all participants. NAA and NAA/Cr concentrations were found lower in bilateral frontal and thalamic regions in JME group as compared with the control group (p < 0.05). There was no difference in frontal and thalamic GLX, GLX/Cr, Cho, Cho/Cr levels in between JME patients and controls (p > 0.05). JME patients were found more unsuccessful than the controls in attention, memory, visuospatial function, verbal fluency, Trail B test and executive functions, stroop test, clock drawing test and Trail A test (p < 0.05). Prefrontal NAA/Cr level was positively related to visual attention, memory, stroop test and thalamic NAA/Cr level was positively related to linguistic memory and Wisconsin card sorting test in JME patients. This research highlights regional brain changes and cognitive decline in JME patients and suggests that MRS may be a sensitive technique for showing subclinical cognitive changes.

Calculation of the mastoid cell volume of infants from computed tomography imaging.

OBJECTIVE: The objective of this study was to calculate the mastoid cell volume of infants using computed tomography imaging. METHODS: We calculated the mastoid cell volumes of 87 infants younger than 1 year classified into 4 age groups. RESULTS: There were significant (P = 0.0001) differences in the ear mastoid cell volumes (cm(3)) among the 0- to 3-, 4- to 6-, 7- to 9-, and 10- to 12-month age groups. Generally, the mastoid cell volume increased with age. CONCLUSIONS: Mastoid cell volume correlates with the age of infants up to 1 year. We plan to expand this study and determine cutoff values for the mastoid cell volumes of infants.

Non-invasive detection of infection in acute pancreatic and acute necrotic collections with diffusion-weighted magnetic resonance imaging: preliminary findings.

PURPOSE: The purpose of this study was to evaluate the contribution of diffusion-weighted magnetic resonance imaging (DW-MRI) to the detection of infection in acute pancreatitis-related collections. METHODS: A total of 21 DW-MRI, and computed tomography (CT) were performed on 20 patients diagnosed as acute pancreatitis with acute peri-pancreatic fluid or necrotic collections. Collections were classified as infected or sterile according to the culture and follow-up results. Collections with gas bubbles on CT images were considered to be infected. Collections with peripheral bright signals on DW-MRI images were considered to be positive, whereas those without signals were considered to be negative. Apparent diffusion coefficient (ADC) values of the peripheral and central parts of the collections were measured. Student's t test was used to compare the means of ADC values of independent groups. RESULTS: Apart from one false positive result, the presence of infection was detected by DW-MRI with 95.2% accuracy. The sensitivity and accuracy of DW-MRI were higher than CT for the detection of infection. The ADC values in the central parts of the collections were significantly different between the infected and sterile groups. CONCLUSION: DW-MRI can be used as a non-invasive technique for the detection of infection in acute pancreatitis-associated collections.

Use of sonography for evaluation of the cervical and thoracic esophagus in children.

OBJECTIVES: The purpose of this study was to determine the normal sonographic appearance of the cervical and thoracic esophagus and to provide corresponding measurements in healthy children. METHODS: In this prospective study, 93 children (51 girls and 42 boys) 1 to 15 years of age were examined sonographically. With the patient in a supine position for evaluation of the cervical esophagus, the ultrasound transducer was placed on both sides of the trachea. To evaluate the thoracic esophagus, the hands were raised over the head, and the ultrasound transducer was placed along the left side of the sternum. The length of the cervical esophagus was measured longitudinally, and the anteroposterior and transverse diameters of the cervical and thoracic esophagus were measured transversely, as was the thickness of the cervical esophageal wall. RESULTS: The cervical esophagus was identified in all of the children, whereas the thoracic esophagus was shown in 41 (44%) of the 93 participants. The length of the cervical esophagus and anteroposterior and transverse diameters of the cervical and thoracic esophagus increased with age. The mean thickness of the cervical esophagus was 2.8 mm at all ages. The cervical esophageal wall appeared as 5 layers on the sonograms, and the lumen was distinct. CONCLUSIONS: Evaluation of the cervical esophagus was readily achievable with sonography in children, whereas visualization of the thoracic esophagus was difficult because of the deep location, small size, and influence of bones and gas in the lungs. Conventional sonography can be easily used in the evaluation of cervical esophageal diseases in children.

Utility of diffusion-weighted imaging in the diagnosis of acute appendicitis.

OBJECTIVES: To evaluate the value of diffusion-weighted MRI (DWI) in the diagnosis of acute appendicitis. METHODS: 119 patients with acute appendicitis and 50 controls were enrolled in this prospective study. DWI was obtained with b factors 0, 500 and 1000 s/mm² and were assessed with a visual scoring system by two radiologists followed by quantitative evaluation of the DW images and ADC maps. RESULTS: Histopathology revealed appendicitis in 79/92 patients (78%) who had undergone surgery. On visual evaluation, except for one patient with histopathologically proven appendicitis all inflamed appendixes were hyperintense on DWI (98.7%). Quantitative evaluation with DW signal intensities and ADC values revealed a significant difference with normal and inflamed appendixes (p < 0.001). The best discriminative parameter was signal intensity (b 500). With a cut-off value of 56 for the signal intensity the ratio had a sensitivity of 99% and a specificity of 97%. The cut-off ADC value at 1.66 mm²/s had a sensitivity of 97% and a specificity of 99%. CONCLUSION: DWI is a valuable technique for the diagnosis of acute appendicitis with both qualitative and quantitative evaluation. DWI increases the conspicuity of the inflamed appendix. We recommend using DWI to diagnose acute appendicitis.

Diffusion-weighted imaging of the rectosigmoid colon: preliminary findings.

OBJECTIVES: The aims of this study were to determine and evaluate the apparent diffusion coefficient (ADC) values of the rectal wall for identifying inflammatory bowel disease (IBD) and rectosigmoid (rectum and sigmoid colon) malignancies. METHODS: Diffusion-weighted magnetic resonance imaging (DWI) findings of 23 patients (mean age, 57 years) consisting of 14 patients with rectosigmoid adenocarcinomas and 9 patients with IBD (6 with ulcerative colitis and 3 with Crohn disease) were retrospectively reviewed. In addition, 30 healthy controls (mean age, 45 years) were enrolled in the study. Diffusion-weighted imaging was performed with b factors of 0, 500, and 1000 s/mm2. RESULTS: The mean (SD) ADC values of the control, IBD, and rectosigmoid adenocarcinoma groups were 1.47 (0.19) x 10(-3) mm2/s, 1.37 (0.12) x 10(-3) mm2/s, and 0.97 (0.14) x 10(-3) mm2/s, respectively. Among the patients with IBD, 2 were in the active, and the rest were in the inactive period, with mean (SD) ADC values of 1.21 (0.08) x 10(-3) and 1.42 (0.09) x 10(-3), respectively. The ADC values of the normal rectum and rectosigmoid malignancy group and rectosigmoid carcinoma and IBD groups were significantly different (P < 0.01). A cutoff value for carcinomas of 1.14 x 10(-3) mm2/s yielded a sensitivity and specificity of 93.3% and 93.3%, respectively. CONCLUSIONS: Our preliminary findings show that quantitative DWI may be able to differentiate the normal rectum from neoplastic involvement, in addition to distinguishing between inflammatory and neoplastic involvements. However, radiologists should be aware of possible overlaps that may lead to misdiagnoses when DWI is used alone.

The role of HRCT versus CXR in children with recurrent pulmonary infections.

The purpose of this study is to evaluate the role of high-resolution computed tomography (HRCT) versus chest radiography (CXR) in children with recurrent respiratory infections. Fifty-one cases, aged 2 months-13 years, who had a history of recurrent respiratory infections, were examined with CXR and HRCT. HRCT showed that 16/51 of the cases had bronchiectasis. CXR revealed findings of bronchiectasis only in 5 of the 16 cases. HRCT showed peribronchial thickening in 18 cases, whereas CXR showed the same finding in 5 patients. Overall, HRCT showed the underlying pathology and sequel of pulmonary lesions in 22 out of 51 cases, and linear densities in 12. Compared with the CXR, HRCT gives much more information.

The sensitivity of MR colonography using dark lumen technique for detection of colonic lesions.

BACKGROUND/AIMS: To assess the detectability of the lesions with magnetic resonance (MR) colonography using dark lumen technique that had been detected on conventional colonoscopy. MATERIALS AND METHODS: A total of 38 patients who were suspected to have a colorectal mass between April 2008 and June 2010 were included in this prospective study. Warm tap water was administered via a rectal tube to the patients in prone position. Then, axial T2 true- fast imaging with steady-state precession (FISP), axial T2 half-Fourier acquisition single-shot turbo spin-echo (HASTE), diffusion-weighted images, and T1 vibe fat suppression coronal sequences were obtained. T1 vibe fat suppression sequences on axial coronal planes were repeated after gadolinium contrast medium intravenous injection. MR images were analyzed by two radiologists concurrently. Assessments were done by comparing with conventional colonoscopy and histopathologic findings. RESULTS: Thirteen out of 20 lesions that had been detected on conventional colonoscopy were correctly obtained by MR colonography. None of the three lesions 5 mm or below was seen on MR colonography. Two out of 4 lesions measuring 6-9 mm were seen on MR colonography (50%). Eleven out of 13 lesions 10 mm and above were correctly detected on MR colonography (84.6%). Sensitivity was estimated as 65% when all lesions were evaluated together. CONCLUSION: MR colonography has a high sensitivity in the diagnosis of colonic pathologies without ionizing radiation. Future investigation will likely lead to wider acceptance of this method to detect colonic pathologies, including perhaps their use in colon cancer screening programs.

Contribution of diffusion-weighted imaging to diagnosis and staging of cervical cancer.

BACKGROUND: Cervical cancer is the second most common female malignancy worldwide. Although its incidence has decreased in developed countries due to screening with Papanicolaou test, it is still the leading cause of cancer-related female death in developing countries. AIMS: The aim of this study was to determine whether the apparent diffusion coefficient (ADC) measurements calculated from diffusion-weighted imaging (DWI) images had any contribution in differentiation of normal cervical tissue from malignant lesions preoperatively, and whether there was a correlation between the mean ADC values and tumor type, grade, or stage in malignant lesions. STUDY DESIGN: Case-control study. METHODS: Mean ADC values in 25 patients who had cervical cancer proved histopathologically, and 20 patients with otherwise normal uterus were compared. Also in the study group, mean ADC values were compared between histopathologic subtypes, tumor grades, and stages. RESULTS: In the study group the mean ADC values (0.96±0.15×10(-3) mm(2)/s) were statistically lower than that of the control group (1.67±0.17×10(-3) mm(2)/s) (p<0.05). According to histopathologic sub-types there was no significant difference between mean ADC values of squamous cell cancer and adenocarcinoma (0.95×10(-3) mm(2)/s and 0.91×10(-3) mm(2)/s, respectively) (p>0.05). There was also no significant difference between the mean ADC values of the tumor grades (p>0.05). The mean ADC values in early stage cervical cancer (0.86±0.05×10(-3) mm(2)/s) were significantly lower than the mean ADC values in late stage disease (0.98±0.06×10(-3) mm(2)/s) (p<0.05). CONCLUSION: ADC value measurements may provide useful information in diagnosis of cervical cancer as well as in preoperative assessment of the tumor stage.

Multidetector CT angiography versus arterial duplex USG in diagnosis of mild lower extremity peripheral arterial disease: is multidetector CT a valuable screening tool?

OBJECTIVE: To prospectively compare the efficacy of 40-row multidetector computed tomography angiography (MDCTA) and duplex ultrasonography (DUS) to diagnose mild peripheral arterial occlusive disease (PAOD) in lower leg and to search whether MDCTA can be used as a screening tool. METHODS: Forty-three patients with intermittent claudication and leg pain, diagnosed as mild PAOD, had undergone DUS and MDCTA of lower limb. The arteries of lower leg were initially scanned by DUS, followed by MDCTA. Both modalities were compared for detecting the obstructed and stenotic segments. RESULTS: A total of 774 vessel segments were imaged by both modalities. When all arteries were considered, MDCTA detected obstructed or stenotic lesions in 16.8% of arteries, versus 11.1% compared to DUS. When suprapopliteal arteries alone were considered, MDCTA detected lesions in 15.0% of arteries, versus 11.0% with DUS. When infrapopliteal arteries only were considered, MDCTA detected lesions in 19.6% of arteries, versus 11.3% with DUS. MDCTA showed 5.7% (95% CI: [3.5%, 7.9%]) more lesions than DUS when all arteries were considered together, 8.3% (95% CI: [4.6%, 12.0%]) more lesions when only the infrapopliteal arteries were compared, and 4.0% (95% CI: [1.3%, 6.8%]) more lesions when only suprapopliteal arteries were compared (p<0.01 for all comparisons). CONCLUSION: 40-row MDCTA may be used as a screening tool in patients with mild lower extremity PAOD as it is a non-invasive and more accurate modality when compared to DUS.

Respiratory gated multidetector computed tomography: applicable for diagnostic abdominal imaging?

PURPOSE: To evaluate the ability and accuracy of a respiratory gated technique used with contrast enhanced MDCT of the upper abdomen with focus on diagnostic image quality and depiction of organs and major vessels. MATERIALS AND METHODS: Forty-five adult patients who were referred to our institution for follow-up dynamic contrast enhanced abdominal CT imaging were included in this study. Respiratory gated CT scans were performed with the use of a dedicated hardware. A multiphasic CT scan was performed for each patient. Respiratory gated images were obtained between early arterial and portal venous phases during free breathing. Images of respiratory gated (RG) and breathhold (BH) phases were compared qualitatively and quantitatively by two radiologists. Definitive statistical methods were used for evaluating the scoring data, while Mann Whitney U test was used for comparison. Statistical significance was accepted for p values <0.05. RESULTS: Statistical significant difference was found for comparison of scores regarding luminal opacification and contoural integrity of intrahepatic vascular structures with scores of RG scans rated poor to moderate (e.g. 2.86+/-1.07 for luminal opacification of intrahepatic portal veins as well as border detectability) in comparison to scores of BH scans rated good to excellent (e.g. 1.37+/-1.31 for luminal opacification, 1.35+/-1.28 for border detectability of intrahepatic portal veins, p<0.001). Furthermore, statistical significant differences were found for general image noise levels (p<0.001). CONCLUSIONS: Further technical advances of RG technique could enable routine use of this technique for selected patient groups.

Fire-eater's pneumonia characterized by pneumatocele formation and spontaneous resolution.

Liquid hydrocarbons derived from petroleum are widely used in industry and in households. Aspiration of massive amounts may lead to an acute and fatal form of exogenous lipoid pneumonia (fire-eater's pneumonia). We present a rare case of chemical pneumonitis following accidental lamp oil aspiration characterized by pneumatocele formation and spontaneous resolution. Initial findings on posteroanterior chest radiographs were smoothly circumscribed lower zone masses with and without air-fluid levels. Chest computed tomography also showed multiple thin-walled cavities with and without air-fluid levels. Complete resolution of findings despite initial severe presentation without corticosteroid or antibiotic treatment is noteworthy.

Virtual and fiber-optic bronchoscopy in patients with indication for tracheobronchial evaluation.

OBJECTIVE: The aim of this study was to compare the results of virtual bronchoscopy (VB) images in defining tracheobronchial pathologies with those of fiber-optic bronchoscopy (FOB) in patients with clinical indication for bronchoscopy. METHODS: Twenty-two patients with bronchoscopy indication were evaluated with FOB and VB. The VB results were evaluated blindly, independent of the FOB results. RESULTS: In 19 of the 22 patients, tracheobronchial abnormalities were present on FOB, whereas 3 patients had normal findings on FOB. In 17 of 19 patients, VB demonstrated the FOB diagnosis of tracheobronchial abnormality. While FOB detected 11 endoluminal lesions, VB detected 6. While FOB detected 20 obstructive lesions, VB detected 26. In evaluating external compression, FOB detected 2 lesions and VB detected 15. CONCLUSIONS: VB is a non-invasive, uncomplicated, and reproducible examination method in patients with an indication for thorax examination. Virtual bronchoscopy could find a clinically broader field of application in the future.

T2-weighted MRI of the upper abdomen: comparison of four fat-suppressed T2-weighted sequences including PROPELLER (BLADE) technique.

RATIONALE AND OBJECTIVES: The aim of this study was to compare four different fat-suppressed T2-weighted sequences with different techniques with regard to image quality and lesion detection in upper abdominal magnetic resonance imaging (MRI) scans. MATERIALS AND METHODS: Thirty-two consecutive patients referred for upper abdominal MRI for the evaluation of various suspected pathologies were included in this study. Different T2-weighted sequences (free-breathing navigator-triggered turbo spin-echo [TSE], free-breathing navigator-triggered TSE with restore pulse (RP), breath-hold TSE with RP, and free-breathing navigator-triggered TSE with RP using the periodically rotated overlapping parallel lines with enhanced reconstruction technique [using BLADE, a Siemens implementation of this technique]) were used on all patients. All images were assessed independently by two radiologists. Assessments of motion artifacts; the edge sharpness of the liver, pancreas, and intrahepatic vessels; depictions of the intrahepatic vessels; and overall image quality were performed qualitatively. Quantitative analysis was performed by calculation of the signal-to-noise ratios for liver tissue and gallbladder as well as contrast-to-noise ratios of liver to spleen. RESULTS: Liver and gallbladder signal-to-noise ratios as well as liver to spleen contrast-to-noise ratios were significantly higher (P < .05) for the BLADE technique compared to all other sequences. In qualitative analysis, the severity of motion artifacts was significantly lower with T2-weighted free-breathing navigator-triggered BLADE sequences compared to other sequences (P < .01). The edge sharpness of the liver, pancreas, and intrahepatic vessels; depictions of the intrahepatic vessels; and overall image quality were significantly better with the BLADE sequence (P < .05). CONCLUSION: The T2-weighted free-breathing navigator-triggered TSE sequence with the BLADE technique is a promising approach for reducing motion artifacts and improving image quality in upper abdominal MRI scans.

Diffusion-weighted MRI of urinary bladder and prostate cancers.

PURPOSE: The purpose of this study was to evaluate the feasibility of diffusion-weighted imaging in the diagnosis of the urinary bladder and prostate carcinomas. The apparent diffusion coefficient (ADC) values of the malignant and normal tissues were correlated. MATERIALS AND METHODS: A total of 23 patients with 14 urinary bladder carcinomas and 9 prostate carcinomas, and 50 healthy controls with normal ultrasonographic urinary bladder and prostate gland imaging findings were enrolled in the study. The ADC values were reported as the mean +/- standard deviation. Student's t test was performed to compare the ADC values of the normal and pathological tissues. Diffusion-weighted imaging (DWI) was performed with b factors of 0, 500, and 1000 s/mm(2), and the ADC values of the normal tissues and lesions were calculated. RESULTS: The mean ADC value of the urinary bladder wall of the control group and bladder carcinomas were (2.08 +/- 0.22 x 10(-3)mm(2)/s) and (0.94 +/- 0.18 x 10(-3)mm(2)/s), respectively. In addition, the ADC values of the normal peripheral (2.07 +/- 0.33 x 10(-3)mm(2)/s), transitional zones (1.46 +/- 0.23 x 10(-3)mm(2)/s) of the prostate, seminal vesicles (2.13 +/- 0.13 x 10(-3)mm(2)/s) and the prostate carcinomas (1.06 +/- 0.17 x 10(-3)mm(2)/s) were calculated. The comparison of mean ADC values of the peripheral-transitional zones of the prostate, normal bladder wall-bladder carcinomas, and peripheral zone prostate carcinomas were statistically significant (P < 0.01). CONCLUSION: The present study demonstrated that ADC measurement has a potential ability to differentiate carcinomas from normal bladder wall and prostate gland.

Non-breath-hold high b-value diffusion-weighted MRI with parallel imaging technique: apparent diffusion coefficient determination in normal abdominal organs.

PURPOSE: To detect apparent diffusion coefficient (ADC) values in normal abdominal organs using non-breath-hold high b-value diffusion-weighted magnetic resonance imaging (DW-MRI) with a parallel imaging technique. MATERIALS AND METHODS: A total of 50 patients with normal abdominal MRI findings were retrospectively enrolled. DW-MRI was performed with b-factors of 0, 500, and 1000 s/mm(2). Mean ADC measurements were calculated. RESULTS: There were statistically significant differences (P < 0.001) between the ADC values of four liver segments (left lobe lateral segment: 1.77 +/- 0.21 x10(-3) mm(2)/s, left lobe medial segment: 1.59 +/- 0.21 x 10(-3) mm(2)/s, right lobe anterior segment: 1.46 +/- 0.18 x 10(-3) mm(2)/ s, right lobe posterior segment: 1.34 +/- 0.20 x 10(-3) mm(2)/s). The ADC value for the left lobe lateral segment was significantly higher than the values for the other segments. The calculated ADC values for cortex and medulla of kidney were 2.08 +/- 0.22 x 10(-3) mm(2)/ s, 1.94 +/- 0.18 x 10(-3) mm(2)/s, respectively; (P < 0.001), for pancreas tail 1.59 +/- 0.38 x 10(-3) mm(2)/s, for pancreas body 1.68 +/- 0.26 x 10(-3) mm(2)/s, pancreas head 1.65 +/- 0.29 x 10(-3) mm(2)/s, stomach wall 1.84 +/- 0.22 x 10(-3) mm(2)/s, and spleen 1.28 +/- 0.38 x 10(-3) mm(2)/s. CONCLUSION: Knowledge of ADC values for normal abdominal organs will be required during quantitative evaluation of DW-MR images in diseases in accordance with the technique used. We believe that further studies investigating the effect of diseases on normal ADC values are necessary and would be helpful in quantitative DWI.