Correlation between Non-Alcoholic Fatty Liver Disease and Visceral Adipose Tissue in Non-Obese Chinese Adults: A CT Evaluation

OBJECTIVE: To investigate the correlation between non-alcoholic fatty liver disease and visceral adipose tissue in non-obese Chinese adults using computed tomography (CT). MATERIALS AND METHODS: The study included 454 subjects undergoing abdominal CT scan. Degree of CT attenuation in liver and spleen, and the degree of fat infiltration in liver were evaluated according to three indices: the attenuation value of liver parenchyma (CTLP), the attenuation ratio of liver and spleen (LSratio) and the attenuation difference between liver and spleen (LSdif). Visceral fat area (VFA) and total fat area (TFA) at L2/3 and L4/5 levels were measured, and the abdominal subcutaneous fat area (SFA) was calculated. Bivariate correlation analysis was carried out to determine the correlation among these factors. RESULTS: In men, VFA, SFA and TFA at L2/3 and L4/5 levels showed significant differences in terms of the three indices to distinguish fatty liver from non-fatty liver (all, p < 0.001). In men, all the three indices showed negative correlation with TFA, SFA and VFA (all, p < 0.001). The negative correlation between the three indices and VFA at the L2/3 level was higher than at L4/5 level (r = −0.476 vs. r = −0.340 for CTLP, r = −0.502 vs. r = −0.413 for LSratio, r = −0.543 vs. r = −0.422 for LSdif, p < 0.001, respectively). The negative correlation between LSratio, LSdif and VFA at L2/3 and L4/5 levels was higher than SFA at the corresponding level. In women, all the three indices showed negative correlation with VFA and TFA at L2/3 and L4/5 levels, and the negative correlation between CTLP and VFA was higher at L2/3 level than at L4/5 level (r = −0.294 vs. r = −0.254, p < 0.001). CONCLUSION: In non-obese Chinese adults, the degree of hepatic fatty infiltration showed a strong correlation with abdominal fat on CT. VFA at L2/3 level was more closely related to fatty liver compared with VFA at L4/5 level.

Confounding Effect in Clinical Research of Otolaryngology and Its Control / 中国医学科学杂志(英文版)

Confounding effect is a critical issue in clinical research of otolaryngology because it can distort the research's conclusion. In this review, we introduce the definition of confounding effect, the methods of verifying and controlling the effect. Confounding effect can be prevented by research's design, and adjusted by data analysis. Clinicians would be aware and cautious about confounding effect in their research. They would be able to set up a research's design in which appropriate methods have been applied to prevent this effect.They would know how to adjust confounding effect after data collection. It is important to remember that sometimes it is impossible to eliminate confounding effect completely, and statistical method is not a master key. Solid research knowledge and critical thinking of our brain are the most important in controlling confounding effect.

Genetic Effects on Sensorineural Hearing Loss and Evidence-based Treatment for Sensorineural Hearing Loss / 中国医学科学杂志(英文版)

In this article, the mechanism of inheritance behind inherited hearing loss and genetic susceptibility in noise-induced hearing loss are reviewed. Conventional treatments for sensorineural hearing loss (SNHL), i.e. hearing aid and cochlear implant, are effective for some cases, but not without limitations. For example, they provide little benefit for patients of profound SNHL or neural hearing loss, especially when the hearing loss is in poor dynamic range and with low frequency resolution. We emphasize the most recent evidence-based treatment in this field, which includes gene therapy and allotransplantation of stem cells. Their promising results have shown that they might be options of treatment for profound SNHL and neural hearing loss. Although some treatments are still at the experimental stage, it is helpful to be aware of the novel therapies and endeavour to explore the feasibility of their clinical application.

Three-dimensional fluid attenuated inversion recovery imaging at 3T MRI in sudden deafness: its findings and relationship with the prognosis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate inner ear of patients with sudden deafness with three-dimensional fluid attenuated inversion recovery (3D FLAIR) MRI, and the relationship between the results of 3D FLAIR and the prognosis.</p><p><b>METHODS</b>Twenty-three patients with sudden deafness received 3D FLAIR at 3T MRI, and the signals of inner ear were recorded. Hearing levels were evaluated at initial visit and after treatment. The relationship between 3D FLAIR findings and hearing prognosis was evaluated.</p><p><b>RESULTS</b>Eight patients with sudden deafness showed high signals in the affected cochlea on 3D FLAIR, the others of affected cochlea and all of contralateral cochlea showed no signal on 3D FLAIR. The age, sex, affected side, period to initial visit and initial audiogram had no difference between cochlea no signal group and high signal group. The average auditory threshold (x±s) in cochlea high signal group (90±21) dB HL was significant higher than that in cochlea no signal group (60±28) dB HL, P<0.05 at patients' discharge. After treatment, in cochlea no signal group, two cases' hearing was complete recovered, remarkable improvement in five cases, slight improvement in two cases and no change in six cases. In cochlea high signal group, hearing was slight improvement in one case and no change in seven cases. The prognosis was significant difference between two groups. Five of seven patients with vertigo and sudden deafness showed high signal in affected side vestibule on 3D FLAIR, and the hearing of whom had no change after treatment.</p><p><b>CONCLUSION</b>3D FLAIR can show high signal in affected inner ear in sudden deafness patients, and which is related to a poor hearing prognosis.</p>

A pilot study of hepatic fibrosis with magnetic resonance diffusion-weighted imaging in a rabbit model / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To evaluate the role of MRI diffusion imaging in the diagnosis of hepatic fibrosis.</p><p><b>METHODS</b>Fifty-eight rabbits were divided randomly into a blank control group (n = 10) and a model group (n = 48). Carbon tetrachloride was injected intraperitoneally into the animals of the model group to induce liver fibrosis. SE-EPI sequence was used in diffusion weighted imaging for all the rabbits. Then apparent diffusion coefficient (ADC) and exponential apparent diffusion coefficient (EADC) of their livers were obtained with Functool 2.0 software. The degrees of liver fibrosis of the rabbits were graded with histological examinations. Statistical analysis was performed by SPSS 11.0 statistical software. One-way analysis of variance was used to compare every rank data respectively. P less than 0.05 was considered statistically significant.</p><p><b>RESULTS</b>When the b value was 300 s/mm2, ADC of diffusion-weighted imaging (DWI) was (2.460+/-0.424) x 10(-3) in the control group (S0). ADCs were (2.170+/-0.311) x 10(-3), (1.950+/-0.248) x 10(-3), (1.635+/-0.296) x 10(-3), (1.566+/-0.353) x 10(-3) in the model group (S1, S2, S3 and S4). EADC of DWI was 0.102+/-0.044 in the control group and were 0.167+/-0.047, 0.183+/-0.042, 0.216+/-0.054, 0.219+/-0.048 in the model group (S1, S2, S3 and S4). ADC and EADC of the control group and model group had significant differences (F = 12.13, P = 0.0006; F = 10.06, P = 0.004 respectively). When the b value was 500 s/mm2, ADC of DWI was (2.044+/-0.215) x 10(-3) in the control group, ADC were (1.907+/-0.223) x 10(-3), (1.785+/-0.232) x 10(-3), (1.542+/-0.268) x 10(-3), (1.312+/-0.212) x 10(-3) in the model group (S1, S2, S3 and S4). EADC of DWI was 0.1106+/-0.069 in the control group and EADCs of DWI were 0.1764+/-0.073, 0.1889+/-0.056, 0.2421+/-0.079, 0.2657+/-0.037 in the model group (S1, S2, S3 and S4). ADCs and EADCs of the control group and model group had significant differences (F = 14.57, P = 0.0002; F = 10.42, P = 0.003 respectively). There was a significant difference of ADCs between S1 and S4 of the model group when b value were 300 s/mm2 and 500 s/mm2 (P = 0.03, P = 0.044 respectively). No differences were found between other subgroups in the model group.</p><p><b>CONCLUSION</b>Our preliminary study shows that measuring ADCs and EADCs has a good potential in diagnosing and quantifying hepatic fibrosis, especially when using b values of 300 sec/mm2 and 500 sec/mm2.</p>

The effect of window setting technique on measuring colon disease in CT virtual colonoscopy / 中华放射学杂志

Objective To study the value of lung window and soft tissue window in measuring colon diseases with experimental CTVC examination.Methods Twenty-four artificial polypoid diseases were placed with glue in a thoroughly cleaned porcine colon(overall length,150 era)that was distented with air and submerged in a water phantom and scanned 10 times on a 64-MSCT(GE Light speed)with identical scanning parameters.The data were reconstructed every 0.625 mm and reviewed using 2D images, navigation,MPR and 3D volume-rendered images on a GE AW 4.2 workstation.The maximum diameters of the artificial polypoids were measured by two radiologists with more than 10 years working experience in lung window(W = 1000,L =-700)and soft tissue window(W =400,L =40),respectively.The average value of maximum diameters of the artificial polypoids were measured for 10 times and were compared with the actual diameter.Results Twenty-four artificial polypoid diseases and their shape,size,loeation and relation of diseases with bowel wall were all showed excellently.The maximum diameter measured was close to the actual diameter.The average value was mostly less than actual diameter and a few of them more than the actual diameter.The maximum diameter measured in lung window was close to the actual diameter,and there was no difference between the two data sets(t =0.431,P =0.669).There was difference between the maximum diameter measured in soft tissue window and the virtual diameter(t = 2.691,P = 0.010). Conclusion In screening the colon diseases,CTVC is a good method of choice with no insult or less insult, and higher repeatability.The lung window should be chosen in measuring colon diseases in CTVC examination.

A fMRI study of item memory and source memory / 中华神经科杂志

Objective To examine the neural basis of item memory and source memory with fMRI approach.Methods Eight male and eight female healthy fight-handed native Chinese speakers were involved in this study.The item memory and source memory task were conducted with 504 highly frequent Chinese double-character words in the Block-designed experiment.Participants underwent such a double- round procedure as fMRI scanning following study.The fMRI data collected from a GE 1.5T MRI system were analyzed to generate corresponding activation maps for females and males respectively(P20)using statistical parametric mapping software(SPM).Results For females,item memory task activated the bilateral dorsolateral prefrontal cortex(BA6,the number of activated voxel clusters was 62 or 11 in the left and the right,respectively),source memory more activated the left dorsolateral prefrontal cortex(BA6/46,the number was 59).For males,item memory activated the right dorsolateral prefrontal cortex(BA6/46,the number was 64),source memory activated the bilateral dorsolateral prefrontal cortex(BA6,9 and 40 in the left and the right).Conclusion On the neural basis of item or source memory,there exists dissociation,which is that right dorsolateral prefrontal areas are more activated by item memory while left dorsolateral prefrontal areas by source memory.For the difference of gender,it is suggested that left dorsolateral prefrontal areas(BA6/46)are more activated in females while right dorsolateral prefrontal cortex(BA6/46)more in males.

Ultrasmall superparamagnetic iron oxide-enhanced MRI in a rabbit model of antigen-induced arthritis:a preliminary study / 中华放射学杂志

Objective To investigate the feasibility of ultrasmall superparamagnetic iron oxide- enhanced(USPIO)-enhanced MR imaging for monitoring synovitis of antigen-induced arthritis in rabbit model and explore the optimal MR imaging sequences.Methods Nine female white rabbits with antigen(0.5 ml mBSA,2 mg/ml)induced arthritis of the right knees were used in the study.The left knees of these rabbits and both knees of another 3 rabbits served as the control.Nine to 28 days(mean 21.3 d)after successful model induction,all knees were imaged before and 24 h after intravenously injection of USPIO (0.3 ml/kg),among which 2 rabbits were also imaged at 48 and 72 h after administration of USPIO respectively.The MR protocol included spin-echo(SE) T_1WI,fast spin-echo(FSE)T_2WI,gradient echo (GRE)T_2~* WI and short tau inversion recovery(STIR).Images were analyzed quantitatively and qualitatively based on signal characteristics and patterns of the synovium.Paired t-test was used for the analysis of the signal intensity of inflammatory synovial membrane before and 24 h after injection of USPIO. MR findings were correlated with histopathology.Results Arthritis was successfully induced in all 9 right knees with intraarticular injection of mBSA.Pathological examination revealed hyperplasia of synovium with infiltration of USPIO-loaded-macrophages.MR depicted synovial thickening(thickness 2.07?0.97 mm) and joint effusion.Synovium and joint fluid appeared as slightly hypo- or iso-intense on T_1 WI and hyper- intense on T_2 WI or T_2~* WI.Twenty four hours after USPIO injection,significant T_1 enhancement(ASNR 41.91%?27.94%),negative T_2 and T_2~* enhancement(△SNR -34.92%?11.77% and -57.24%? 16.05%)were demonstrated in the region of synovial inflammation respectively.The signal at 48 h and 72 h changed less than that at hour 24.No signs of arthritis occurred in all left knees and in all knees of the artificial model group.Conclusion Iron oxide phagocytized into macrophages can be a root cause resulted in signal change on USPIO-enhanced MR images.The gradient echo sequence should be the optimal sequence to be used in USPIO-enhanced MR imaging in antigen-induced arthritis.