Magnetic resonance imaging and Crohn's disease endoscopic index of severity: Correlations and concordance.

AIM: To examine the correlation between magnetic resonance imaging (MRI) and endoscopic index of severity (CDEIS) in patients with Crohn's disease (CD). METHODS: This was a retrospective study of 104 patients with CD that were treated at the Ruijin Hospital between March 2015 and May 2016. Among them, 61 patients with active CD were evaluated before/after treatment. MRI and endoscopy were performed within 7 d. CDEIS was evaluated. MRI parameters included MaRIA scores, total relative contrast enhancement (tRCE), arterial RCE (aRCE), portal RCE (pRCE), delay phase RCE (dRCE), and apparent diffusion coefficient. The correlation and concordance between multiple MRI findings and CDEIS changes before and after CD treatment were examined. RESULTS: Among the 104 patients, 61 patients were classified as active CD and 43 patients as inactive CD. Gender, age, disease duration, and disease location were not significantly different between the two groups (all P > 0.05). CRP levels were higher in the active group than in the inactive group (25.12 ± 4.12 vs 5.14 ± 0.98 mg/L, P < 0.001). Before treatment, the correlations between CDEIS and MaRIAs in all patients were r = 0.772 for tRCE, r = 0.754 for aRCE, r = 0.738 for pRCE, and r = 0.712 for dRCE (all MaRIAs, P < 0.001), followed by MRI single indexes. Among the active CD patients, 44 cases were remitted to inactive CD after treatment. The correlations between CDEIS and MaRIAs were r = 0.712 for aRCE, r = 0.705 for tRCE, r = 0.685 for pRCE, and r = 0.634 for dRCE (all MaRIAs, P < 0.001). CONCLUSION: Arterial MaRIA should be an indicator for CD follow-up and dynamic assessment. CD treatment assessment was not completely concordant between CDEIS and MRI.

Hepatitis B virus-induced liver fibrosis and cirrhosis: the value of liver and spleen volumetry with multi-detector spiral computed tomography.

OBJECTIVE: To study the correlation of liver and spleen volume with the degree of liver fibrosis and cirrhosis induced by hepatitis B virus infection. METHODS: 128 participants who had undergone liver and spleen volumetry were enrolled. The control group consisted of 41 participants who were potential living liver donors. The liver fibrosis group consisted of 63 histologically proved liver fibrosis patients who were further divided into two subgroups: 44 patients with slight liver fibrosis, and 19 patients with advanced liver fibrosis. The liver cirrhosis group consisted of 24 patients. The following parameters were determined by multi-detector spiral computed tomography (MSCT) examination: total liver volume (TLV), right liver lobe volume (RV), left lateral liver segment volume (LLV), left medial liver segment volume (LMV), caudate lobe volume (CV), and spleen volume (SV). The ratios of CV to TLV (C/T), RV to TLV (R/T), LLV to TLV (LL/T), LMV to TLV (LM/T), and SV to TLV (S/T) were calculated. RESULTS: TLV, RV, LMV tended to decrease and SV, C/T, S/T tended to increase gradually with the increased degree of fibrosis. C/T >or= 3.34% and S/T >or= 47.36% were identified as the cut-off values of fibrosis >or=F3 (advanced liver fibrosis) and cirrhosis, respectively. Their sensitivities were 68.4% and 87.5% and their specificities were 59.1% and 89.5%, respectively. CONCLUSION: Variations in liver and spleen volume correlated with the degree of liver fibrosis and cirrhosis and could be used in the non-invasive follow-up of the development of liver fibrosis.

[Investigation on spectrum of B 2sigma(+)-X 2sigma+ and C 2pi(r)-X 2sigma+ bands of AlO radical in shock tube].

There are some impurities such as aluminum dioxide adhering on the shock tube wall due to the ablating and heating of the aluminum diaphragm by high temperature gas. Under high temperature, the collision of AlO radicals with the gaseous molecules leads to transition of the electronic states and production of strong radiation, which disturb the analysis of radiation spectrum of heated gases in shock tube. In the authors' experiments, the air in the test section with adhering aluminum dioxide was heated to some 4 000-7 000 K, the spectrum of AlO radical was obvious in the range of 460-530 nm, which corresponds to B 2sigma(+)-X 2sigma+ (T00 = 20 689 cm(-1) band. There were several band heads for this band, the interval of neighbor heads was some 2 nm, and all the band heads were with the shortest wavelength. The characteristics of B 2sigma(+)-X 2sigma+ band were explored in experiment and by theory. In addition, the spectrum of C 2pi(r)-X 2sigma+ (T00 = 33 047 cm(-1)) band was also investigated. The corresponding strength was lower than that of B 2sigma(+) -X 2sigma+ band, and the wavelength range of this band was some 270-335 nm where the radiation of A 2sigma(+) -X 2pi (T00 = 32 682 cm(-1)) band of OH radical also existed. This occurrence of the two bands in the same wavelength range is disadvantageous for the spectrum analysis.

Feasibility of diagnosing and staging liver fibrosis with diffusion weighted imaging.

OBJECTIVE: To assess the clinical feasibility of diagnosing and staging liver fibrosis by apparent diffusion coefficient (ADC). METHODS: Totally, 43 patients (mean age 29.3 years) with chronic hepatitis by liver biopsy and 7 healthy controls (mean age 39.9 years) underwent liver diffusion weighted imaging (DWI) with four b values: 0, 200, 500, and 1000 s/mm2 respectively. The liver fibrosis was staged according to Ishak fibrosis stage. The ADC value of liver fibrosis patients and healthy controls was compared. The correlation of ADC value and liver fibrosis staging was analyzed. RESULT: The histological staging showed 8 stage 1 patients, 10 stage 2 patients, 6 stage 3 patients, 9 stage 4 patients, 8 stage 5 patients and 2 stage 6 patients. The mean ADC value of liver fibrosis patients was significantly lower than that of healthy controls except for stage 1 group (P < 0.05). There was a negative correlation between liver fibrosis staging and ADC value (r = -0.697 with b=500 s/mm2, P < 0.01). Receiver operating characteristic (ROC) curve of ADC value of advanced liver fibrosis (Ishak stage F3 and higher) showed that area under curve = 0.913, 0.825, and 0.794 with b = 500, 1000, and 200 s/mm2, respectively (95% confidence interval: 83.6%-99.0%, 70.7%-94.3%, 66.5%-92.4%; P < 0.05). When b value was 500 s/mm2, the sensitivity (84%) and specificity (80%) of DWI for diagnosis of advanced liver fibrosis were the highest. CONCLUSION: DWI is proved to be a useful clinical tool in the quantitative evaluation of liver fibrosis and in the prediction of the process of liver fibrosis with the recommendable b value (500 s/mm2).