CT and MRI findings in patients with autoimmune pancreatitis / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate computed tomography (CT) and magnetic resonance imaging (MRI) findings in patients with autoimmune pancreatitis (AIP).</p><p><b>METHODS</b>The imaging findings of pancreas and extra-pancreas in 24 patients with AIP were retrospectively reviewed. Among them, CT scan was performed in 18 patients, MRI in 11, and bGth CT and MRI in 10.</p><p><b>RESULTS</b>The pancreas showed diffuse enlargement (25%, 6/24), focal enlargement (37. 5%, 9/24), combined enlargement (25%, 6/24) ,and no enlargement (12. 5%, 9/24). Unenhanced CT showed hypoattenuation in AIP area (n = 2) . After intravenous injection of contrast medium, 17 patients showed abnormal contrast enhancement in the affected pancreatic parenchyma, including hypoattenuation during the arterial phase (50%, 9/18) and hyper attenuation during the delayed phase (94. 4%, 17/18). Precontrast MRI showed abnormal signal intense (n =9), including hypointense on T1-weight images (T1 WI) (n = 7), hyperintense (n = 7) and hypointense (n = 2) on T2-weight images (TIWI). Enhanced MRI demonstrated abnormal contrast enhancement within lesions (n = 11), including hypoattenuation during the arterial phase (81. 8%, 9/11) and good enhancement during the delayed phase (100%, 11111). A capsule-like rim was seen around pancreas (37. 5%, 9/24), among which CT detected in 6 out of 18 patients and MRI found in 7 out of 11 patients.The main pancreatic duct lumen within lesions has no visualization (100%, 24/24) and upstream dilation of the main pancreatic duct (n = 8) , ranging from 2. 2 to 4. 5 mm(mean 3. 1 0. 47 mm) in diameter. Narrowing of the common bile duct was shown in 14 patients. Miscellaneous findings were: infiltration of extrapancreatic vein (n = 9) and artery (n = 1); mild fluid collection around pancreas (n = 2); pseudocysts (n = 3). Fourteen patients also presented one or more of the following extrapancreatic imaging findings: narrowing of the intra-hepatic bile duct or hilar duct (n = 5); thickening of gallbladder wall (n = 5); fibrosis in mesenteric (n = 2), in retroperitoneal (n = 2) and in ligamentum teres hepatis (n = 1); renal involvement (n = 3); peri-pancreatic or para-aortic lymphadenopathy (n = 10); and ulcerative colitis (n = 3).</p><p><b>CONCLUSION</b>AIP display some characteristic CT and MRI imaging features: sausage-like change of the pancreas; capsule-like rims around lesions; delayed contrast enhancement in the affected pancreatic parenchyma; segment or diffuse pancreatic duct stenosis but mild upstream dilation and extrapancreatic organs involvement. CT and MRI findings combining with serological tests and pancreas biopsy can assist physicians to make accurate and timely diagnosis.</p>

MRI scan of striatum volume in healthy adults / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To examine the age, sex, and hemispheric differences in volume of the striatum by MRI in healthy adults.</p><p><b>METHODS</b>The volumes of the bilateral caudate nucleus and putamen were measured on MR images in 100 healthy right-handed adults (18-70 y).</p><p><b>RESULTS</b>The volume of bilateral caudate nucleus and putamen in healthy adults was (8.42 +/-0.88) cm(3) and (8.90 +/-0.89) cm(3), which were decreased with aging (for caudate nucleus r=-0.727, P<0.001; for putamen r=-0.709, P<0.001). The average annual shrinkage rate was 0.52 % in the caudate nucleus and 0.50 % in the putamen. There were no gender differences in the volume of the striatum, however, the age-related shrinkage of the striatum was more evident in men than that in women. The volume of the left caudate nucleus (t=4.43, P<0.001) and the putamen (t=4.88, P<0.001) was greater than that of its right counterpart.</p><p><b>CONCLUSION</b>Bilateral age-related shrinkage of the striatum is found in healthy adults, which is more evident in men than that in women. In both sexes, significant leftward asymmetry in volume of the caudate nucleus and the putamen is found.</p>

Evaluation of kidney oxygen bioavailability in acute renal failure by blood oxygen level dependent magnetic resonance imaging / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To assess the kidney oxygen bioavailability in acute renal failure using blood oxygen level dependent (BOLD) magnetic resonance (MR) imaging.</p><p><b>METHODS</b>Twenty-one patients with acute renal failure, including 18 patients with oliguric renal failure, 1 nonoliguric acute renal failure and 2 functional renal failure were enrolled in the study; 20 healthy subjects served as controls. All subjects received renal functional MR examination. BOLD MR imaging with 16 gradient-recalled-echoes on a 1.5-T scanner were performed. R2(*)(1/sec) values of the cortex and medulla and R2(*) ratio of the medulla to cortex (R2(*) ratio of M/C) of the renal were recorded respectively.</p><p><b>RESULTS</b>The R2(*) values of the medulla was higher than those of the cortex in controls (17.64 +/-1.86/sec vs 13.73 +/-0.49/sec, P<0.00). The R2(*) ratio of M/C in controls was 1.28 +/-0.06. The R2(*) values of the medulla (13.31 +/-4.28/sec) and cortex (12.25 +/-2.41/sec) and the R2(* ) ratio of M/C (1.01 +/-0.25) in oliguric renal failure were lower than those in controls (P <0.05). Patients with functional renal failure and nonoliguric acute renal failure had higher R2(*) values in cortex and medulla and higher R2(*) ratio of M/C than those of controls.</p><p><b>CONCLUSION</b>BOLD MRI demonstrates that decreased R2(*) values of cortex and medulla suggest lower oxygen bioavailability in acute renal failure and decreased R2(*)ratio of M/C suggests the disappearance of a steep cortico-medullary gradient of oxygen.</p>

Asymmetry in internal capsule detected with magnetic diffusion tensor imaging / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the asymmetry of fibers in the posterior limb of the internal capsule with diffusion tensor imaging.</p><p><b>METHODS</b>Twenty-nine volunteers (right-handers: 20, left-handers: 9) were enrolled in this study. All the data were obtained using a 1.5 tesla scanner (Signa EXCITE II. GE Medical Systems). The parameters including apparent diffusion coefficient (ADC), fractional anisotropy (FA) and eigenvalue lambda1, lambda2, lambda3 were acquired from the posterior limb of the internal capsule in both hemisphere of brain, and paired t-test was used for statistical differences between the hemisphere.</p><p><b>RESULTS</b>No differences of ADC and lambda1 were found among the right-handers, but FA in the internal capsule of left hemisphere was larger than that in the right (0.72+/-0.03 compared with 0.70 +/-0.04, P=0.001), and lambda2, lambda3 in the left was lower than that in the right [(4.39+/-0.32 compared with 4.50+/-0.33)x10(-3) mm(2)/s, P=0.016 and (2.19 +/-0.34 compared with 2.29 +/-0.40)x10(-3) mm(2)/s, P=0.024, respectively]. In contrast to the results among the right-handers, all parameters in the left-handers showed no statistical differences.</p><p><b>CONCLUSION</b>The fibers in the posterior limb of the internal capsule of left hemisphere might be well sheathed with myelin among right-handers.</p>

Are there gender differences in iron contents of adult brain: an in vivo susceptibility weighted imaging study / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the gender-related difference in the iron contents of the human brain.</p><p><b>METHODS</b>The brain iron levels were evaluated in vivo in 78 healthy adult volunteers using a noninvasive magnetic resonance method termed susceptibility weighted phase imaging. The subjects consisted of 40 males and 38 females, with the mean age of 41.5+/-11.9 and 45.2+/-15.9, respectively. The phase values were measured on the corrected phase images in the globus pallidus, putamen, caudate, substantia nigra, red nucleus, thalamus and frontal white matter. Phase values of these regions measured from the subjects aged over 30 were correlated with published values of brain iron contents in normal adults to check the validity of the data. Covariance models were used to evaluate the gender effect on the brain iron concentration, with age as the covariate, controlling for the linear effects of age.</p><p><b>RESULTS</b>A strongly negative correlation was showed between the phase values of this study and the reference values (r=-0.796, P=0.032). No significant gender-related difference in the brain iron concentration was found in any regions of interest (P>0.05).</p><p><b>CONCLUSION</b>Gender differences in the iron contents of the adult human brain are not found in this study.</p>

Different patterns of aversive emotion regulation in homosexual and heterosexual men / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To compare the differences between homosexual and heterosexual men in the pattern of induced aversive emotion regulation.</p><p><b>METHODS</b>Ten healthy homosexual men and 10 heterosexual men were investigated by functional magnetic resonance imaging under three types of visual sexual stimuli designed by Block. SPM2 software was used for data analysis.</p><p><b>RESULTS</b>Same levels of negative emotions of homosexual men and heterosexual were induced by female-female and male-male erotic stimuli respectively. Activations of same brain regions including prefrontal gyrus, temporal gyrus, occipital gyrus and cerebellum were observed in two groups. However, there were significant differences in the side of hippocampus and precuneus. Activations of right cingulate cortex were observed in homosexual men, but not in heterosexual men.</p><p><b>CONCLUSION</b>There are some differences in the patterns of aversive emotion regulation between homosexual and heterosexual men.</p>

Cortical language activation in aphasia: a functional MRI study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Functional neuroimaging has been used in neurolinguistic research on normal subjects and on patients with brain damage. This study was designed to investigate the differences of the neural basis underlying language processing between normal subjects and aphasics.</p><p><b>METHODS</b>Functional magnetic resonance imaging (fMRI) was used to map the language network in 6 normal subjects and 3 patients with aphasia who were in the stage of recovery from acute stroke. The participants performed a word generation task during multi-slice functional scanning for the measurement of signal change associated with regional neural activity induced by the task.</p><p><b>RESULTS</b>In normal subjects, a distributed language network was activated. Activations were present in the frontal, temporal, parietal and occipital regions. In the patient group, however, no activation was detected in the left inferior frontal gyrus whether the patient had a lesion in the left frontal lobe or not. Two patients showed activations in some right hemisphere regions where no activation appeared in normal subjects.</p><p><b>CONCLUSIONS</b>fMRI with word generation task is feasible for evaluating language function in aphasic patients. Remote effect of focal lesion and functional redistribution or reorganisation can be found in aphasic patients.</p>

Effects of age on the lenticular nuclei detected by MR diffusion tensor imaging / 中华放射学杂志

50 years).The values of ADC,FA,?_1,?_2 and ?_3 in putamen and globus pallidus were calculated after diffusion tensor scanning,and then analyzed the differences between the two tissues.The differences of ADC,FA,?_1,?_2 and ?_3 values among age groups were analyzed by using analysis of variance(ANOVA),and their relationship with age were accessed by using Pearson correlation.Results Between the correspondent age groups,the ADC value was higher in the putamen[(6.68?0.40)?10~(-4),(6.47?0.36)?10~(-4),(6.44?0.34)?10~(-4)mm~2/s]than that in the golbus pallidus[(6.13?0.50)?10~(-4),(6.05?0.33?10~(-4),(6.05?0.52)?10~(-4)mm~2/s],and the value of FA in the putamen(0.20?0.03,0.23?0.03,0.25?0.03)was lower than that in the globus pallidus(0.35?0.03,0.36?0.03,0.37?0.04).ANOVA analysis of the FA value among age groups revealed there were significant differences in the putamen(F=10.082,P=0.000),and the same analysis of eigenvalue ?_3 in the putamen also showed significant differences(F=5.675,P=0.005).The FA value in the putamen was significantly elevated with aging(r=0.555,P