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Objective: To explore the clinical value of MRI imaging of measuring the iron content for hepatocellular carcinoma (HCC) associated nodules., Methods: 55 male Wistar rats were randomly allocated into a treatment and a control group, which were administered with diethyl nitrosamine (DEN) and the sterilized tap water. According to the macro pathology differences, the treatment groups were divided into three groups: cirrhotic nodules group, cirrhotic nodules with HCC group, and HCC group; According to the micro pathology differences, the treatment groups were divided into four groups: regenerative nodules (RN) group, low grade dysplastic nodules (LGDN) group, high grade dysplastic nodules (HGDN) group, and HCC group. After 13 weeks, the rats were scanned by MRI T2WI and T2 * WI. The next day all rats were sacrificed for histological tests and tissue iron level determination. The correlations were statically analyzed between the values of T2, T2 * and the grades of iron stain, the quantification of tissue iron., Results: With macro pathology observation, the values of T2, T2 * among control group (normal rats) , cirrhotic nodules group, cirrhotic nodules with HCC group, HCC group were increased, while the quantification of tissue iron were decreased. Significant differences were found for T2, T2 * and quantification of tissue iron in three groups (P < 0.05). Low-grade negative correlations could be found between T2, T2 * and quantification of tissue iron in whole samples (r₁ = -0.364, P₁ = 0.000; r₂ = -0.245, P₂ = 0.018). With micro pathology observation, there were significant differences among the control (normal rats), RN, LGDN, HGDN, and HCC groups for the grades of iron stain both in the essence and the interstitial (P < 0.05). After comparison each two groups, significant differences were found among some groups for the grades of iron stain both in the essence and the interstitial (P < 0.05). Generally the grades of iron stain for HCCs were lower than non-HCC both in the essence and the interstitial., Conclusion: Negative correlation between T2, T2 * and iron content demonstrats that T2 and T2 * could roughly estimate the iron content in the cirrhotic nodules. T2 and T2 * measurements could contribute to differential diagnosis of HCC nodules.

Objective: To investigate the change of CD4+ CD25+ FoxP3+ regulatory T cells (Treg)in peripheral blood (PB)and synovial fluid (SF) in patients with rheumatoid arthritis (RA) and its role in RA immune tolerance imbalance., Methods: The frequency of CD4+ CD25+ FoxP3+ Treg in PB and SF cells in active RA patients and healthy volunteers were determined using flow cytometry. The expression of FoxP3 gene in mononuclear cells was analyzed by real-time PCR. The correlation between the frequency of CD4+ CD25+ FoxP3+ Treg in PB cells and disease activity indices was evaluated., Results: (1) Active RA patients had a higher level of CD4+ CD25+ FoxP3+ Treg in SF cells (7.56% +/- 2.89%) than in PB cells (1.84% +/- 0.97%). Their level of CD4+ CD25+ FoxP3+ Treg in SF cells was also higher than that of healthy volunteers (2.19% +/- 0.54%). Anti-CCP antibody (ACPA) positive RA patients had a lower level of CD4+ CD25+ FoxP3+ Treg (1.40% +/- 0.63%) in PB cells compared with the ACPA negative RA patients (2.85 +/- 0.87%). (2) Active RA patients had a higher mRNA level of FoxP3 in SF mononuclear cells than those inactive RA patients and healthy volunteers (P < 0.01). (3) The frequency of CD4+ CD25+ FoxP3+ Treg in PB cells in active RA patients had no correlation with disease activity indices (P > 0.05)., Conclusion: Altered frequency of CD4+ CD25+ FoxP3+ Treg in SF cells of RA patients might contribute to RA immune tolerance imbalance in inflammatory joints.

Objective: To investigate the feasibility of using black tea as a gastrointestinal oral negative contrast agent to null the signal from fluid in bowel during MR cholangiopancreatography (MRCP)., Methods: (1) 15 different drinks were scanned with MRCP, T2-map and T1-map in vitro to identify the most suitable drink for MRCP. (2) 10 volunteers were scanned by MRCP prior to and 5, 10, 15 min after tea consumptions to identify the optimal delay time. (3) 20 patients were scanned with MRCP prior to and 5 min after tea consumptions. The signal intensity (SI) and signal-to-noise ratio (SNR) of stomach, duodenum, liver-parenchyma, common bile duct (CBD), pancreatic duct (PD) and gall bladder (GB); the singal loss of stomach and duodenum; and the image quality of ampulla of vater (AV), intrahepatic ducts (IHD), hepatic duct, CBD, PD and GB were analyzed with Siemens Workstation., Results: (1) Lipton black-tea was identified as the optimal drink in vitro. (2) There were no significant differences in MRCP among the 3 delay times in volunteer tests. (3) The SI, SNR and SI loss of stomach and duodenum, and the image quality of CBD, PD, GB and AV showed a significant improvement of MRCP after tea consumptions (P < 0.05). But tea consumptions made no significant differences in the image quality of IHD and hepatic duct, and the SI and SNR of liver, CBD, GB and PD (P > 0.05)., Conclusion: As a simple, cheap and safe drink, black tea can be widely used to reduce signal intensity of gastrointestinal tract and provide improved image of MRCP.

Objective: To identify the optimal protocol of MR contrast imaging in diabetic foot., Methods: 20 patients with diabetic feet were enrolled and examined with 3D FLASH-MRA, 3D VIBE-WE, 2D SE-FS, 2D TSE-FS and 2D FLASH-FS at a 1.5T MR scanner for vascular changes in feet. Their effectiveness in displaying blood vessels, venous aliasing and articular cartilage, as well as the signal-to-noise ratio (SNR) and contrast ratio (CR) of plantar skins calcaneus, flexor digitorum brevis, dorsal artery, and talocalcaneal joint cartilage in diabetic feet were compared., Results: (1) 3D FLASH-MRA was better in displaying blood vessels and venous aliasing than the others (P < 0.05); (2) 3D VIBE-WE was better in displaying articular cartilage than 2D SE-FS, 2D TSE-FS and 2D FLASH-FS (P < 0.05); (3) 3D VIBE-WE had higher SNR and CR of plantar skins, dorsal artery, talocalcaneal joint cartilage, calcaneus, and flexor digitorum brevis than the others (P < 0.05)., Conclusion: 3D VIBE-WE is the preferred sequence for T1 weighted imaging with contrast in diabetic feet. It can also serve as the supplemental sequence of 3D FLASH-MRA in MR angiography.

Objective: To examine the efficacy of fresh blood imaging (FBI) in detecting vascular diseases in lower extremity., Methods: Thirty-six patients suspected of having lower extremity vascular diseases were imaged with a 1.5-T MRI system (Toshiba Excelart Vantage). Contrast-enhanced MRA (CEMRA) and FBI technology, with maximum intensity projection (MIP) reconstruction were adopted to visualize lower extremity vascular. Signal to noise ratios (SNR) were measured on the FBI and CEMRA images. Two experienced radiologists assessed the imaging quality of peripheral artery MRA on MIP reconstructed images., Results: All patients successfully underwent both FBI and CEMRA. All arterial segments were obtained in the 36 patients. The SNR values on FBI and CEMRA were 108.39 +/- 9.76 and 87.46 +/- 14.77 (t = - 6.782, P = 0.001), respectively. There were no significant differences in the overall image quality, arterial anatomy and venous overlap (chi2 = 0.004, P = 0.947; chi2 = 0.000, P = 1; chi2 = 0.681, P = 0.409). The CEMRA motion artifacts were less than FBI (chi2 = 8.744, P = 0.03)., Conclusion: The FBI technique, which shows the vascular disease in lower extremity without contrast medium with ECG gating, is considered clinically useful.

Objective: To investigate the diagnostic efficacy of gadobutrol for assessing brain metastases in lung cancer patients in comparison with multihance., Methods: 21 patients with lung cancer suspected of brain metastasis were enrolled in this study. All patients underwent twice MRI scans on a 3.0T MRI scanner (Siemens MAGENETOM Trio) with 8-channel head coil, first with 0.5 mol/L multihance and then with 1.0 mol/L gadobutrol as contrast agent. The dosage of contrast agent was set at 0.1 mmol/kg body mass. The interval between the two scans was 24-72 hours. The detection and delineation of lesions were evaluated visually. The signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR) of lesion to normal brain white matter and the percentage of lesion enhancement were calculated and compared between the two scans by 2 experienced neuroradiologists., Results: One patient was excluded because he received radiation therapy between the two scans. 15 patients were found to have brain metastases with a total of 35 lesions. There were no statistical differences between the two scans in SNR, CNR and percentage enhancement for both normal brain and lesions (t = 0.545, P = 0.592; t = 1.143, P = 2.267; t = 0.592, P = 0.557; t = 0.473, P = 0.639)., Conclusion: Half-dose gadobutrol (1.0 mol/L) can achieve the same enhancement effects compared with full-dose multihance (0.5 mol/L).

Objective: To investigate the effect of space saturation technique on the quality of proton magnetic resonance spectroscopy (1 H-MRS) for amygdala., Methods: 22 healthy volunteers were enrolled and scanned at a 3.0T MR scanner. Single voxel H-MRS of amygdala with and without space saturation bands around the region of interest was performed using point-resolved spectroscopy series (PRESS, TR/TE = 1500/30 ms). Raw spectral data were processed and signal-to-noise ratio of creatine (Cr-SNR), water-suppression level, full width at half maximum (FWHM) and root mean square (RMS) noise were obtained and compared between groups with and without saturation bands., Results: The Cr-SNR of spectra without and with saturation bands was 15.506 +/- 6.623 and 22.935 +/- 7.270, respectively [increased by (47.9% +/- 24.94%), P < 0.001]. The water-suppression level of spectra without and with saturation bands was (93.888% +/- 1.079%) and (95.722% +/- 0.461%), respectively [increased by (1.95% +/- 0.68%), P < 0.001]. The FWHM of spectra without and with saturation bands was 7.00 +/- 1.113 and 6.82 +/- 1.181, respectively [decreased by (2.57% +/- 1.12%), P > 0.053. The RMS noise of spectra without and with saturation bands was 0.606 +/- 0.0615 and 0.589 +/- 0.0470, respectively [reduced by (2.81% +/- 1.68%), P > 0.053., Conclusion: Application of space saturation technique significantly elevates the Cr-SNR and the water-suppression level, and thus improves the spectral quality of amygdala without additional scanning time.

Objective: To evaluate the feasibility of nonenhanced renal artery MR angiography (MRA) with respiratory-gated time spatial labeling inversion pulse (time-slip) and its clinical application., Methods: Thirty-two consecutive patients underwent the 1.5 T MRI (TOSHIBA EXCELART Vantage) examination to visualize renal artery with contrast-enhanced MRA (CEMRA) and the examination with time-slip technology. Signal to noise ratio (SNR) and contrast to noise ratio (CNR) were measured on CEMRA and Time-slip images, respectively. Two experienced radiologists assessed the imaging quality of renal artery MRA on 3D-MIPs reconstructed images., Results: Sixty-four renal arteries and 3 accessory renal arteries in 32 patients were visualized on both time-slip and CEMRA. SNR values on Time-slip and CEMRA were 102.7 +/- 16.2 and 83.9 +/- 17.7 (t = -4.625, P < 0.001); CNR were 97.8 +/- 16.1 and 78.8 +/- 18.3 (t = -4.554, P < 0.001), respectively. Time-slip MIP images obtained higher quality than CEMRA did (Z = -2.318, P = 0.02), and venous contamination was sharply reduced on Time-slip technology when compared with CEMRA (Z = -4.895, P = 0.001)., Conclusion: Non-enhanced renal artery MRA with respiratory-gated time-slip technology can provide higher SNR images of renal artery than conventional CEMRA, which can provide more information for clinical decision-making.

Objective: To evaluate the development of optic radiations (ORs) in patients with anisometropia amblyopia using magnetic resonance diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT), and to explore possible mechanism of pathogenesis of amblyopia., Methods: Brain scan was performed with 3.0 Tesla scanner on 8 patients with anisometropia amblyopia and 15 control subjects with normal sights. The fractional anisotropy (FA) values, the apparent diffusion coefficient (ADC) values, the numbers of neural fiber bundle of ORs, and the voxel numbers of ORs were compared between the patients with anisometropia amblyopia and those with normal sights and between the ipsilateral ORs and the contralateral ORs in the patients with amblyopia., Results: No differences in the FA values, the ADC values, the numbers of neural fiber bundle of ORs and the voxel numbers of ORs were found between the ipsilateral ORs and the contralateral ORs in the patients with amblyopia (P > 0.05). Significant decreases in the FA values and the voxel numbers of ORs were found in the patients with amblyopia compared with the controls (P < 0.05). No differences in the voxel numbers of both ORs in the anterior parts were found between the patients with amblyopia and the controls (P > 0.05). However, the patients with amblyopia had more voxel numbers of ORs in the posterior parts than the controls (P < 0.05). The differences in the ADC values and the numbers of neural fiber bundle of ORs between the patients with amblyopia and the controls were not significant (P > 0.05)., Conclusion: The compactability, integrity and directivity of ORs decrease in patients with anisometropia amblyopia. The projection of OR fibers is abnormal. The ORs are underdeveloped, especially in the posterior parts, although no abnormal morphologic changes occur. The DTI and DTT can detect the underdevelopment of optic radiations in patients with anisometropia amblyopia indirectly.

Objective: To test the values of MR spectroscopy (MRS) and fat saturation (FATSAT) in quantifying fat content in pancreas with 3.0T MR., Methods: Thirty-five healthy volunteers were examined with 3 different MR techniques IP/OP, MRS, and FATSAT, to quantify pancreas fat content (FC). The IP/OP result served as a reference standard., Results: The IP/OP, FATSAT and MRS detected (8.2 +/- 2.0)%, (11.8 +/- 4.7)% and (8.8 +/- 4.6)% of pancreas fat content, respectively. The IP/OP result correlated with the MRS result (r = 0.809, P < 0.001), but not with the FATSAT result (r = 0.311, P = 0.069)., Conclusion: For 3.0T MRI, MRS technique can quantify pancreas fat content, but FATSAT can not.

Objective: To identify the brain structural differences of schizophrenia patients and their parents between those with family history and those sporadic cases., Methods: High resolution T1 weighted images were obtained using 3T MR from 10 familial patients and 10 sporadic patients matched with age, sex, years of education and duration of disease. All patients were in their first episode of care. Twenty unaffected parents of the patients (8 for familial cases, 12 for sporadic cases) and 20 normal controls were also examined. The images were preprocessed according to the optimized VBM protocol. Student t test was performed to test the differences of the gray matter density (GMD) of the patients and their parents between the groups with and without family histories, and between the patient groups and the normal controls., Results: Compared with the sporadic group, significant reduce of GMD was observed in bilateral thalamus in both familial schizophrenia patients and their parents. Compared with normal controls, both familial and sporadic schizophrenia patients showed lower GMD in many areas including bilateral insula, right temporal lobe, right occipital lobe, left lenticula, right cerebellum and left rectal gyrus extending to anterior cingulated gyrus. Only familial patients showed lower GMD in the right thalamus. Familial parents also showed lower GMD in several areas including right insula extending to right temporal lobe and right parietal lobule., Conclusion: Familial schizophrenia is associated with genetically related structural abnormalities, especially in the bilateral thalamus. The brain structural differences can explain, at least in part, the symptom differences between familial and sporadic schizophrenia.