[A pilot study of hepatic fibrosis with magnetic resonance diffusion-weighted imaging in a rabbit model].

OBJECTIVE: To evaluate the role of MRI diffusion imaging in the diagnosis of hepatic fibrosis. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Human umbilical cord blood mononuclear cell transplantation promotes long-term neurobehavioral functional development of newborn SD rats with hypoxic ischemic brain injury].

OBJECTIVE: To explore the effect of human umbilical cord blood mononuclear cells (UCBMC) promoting nerve behavior function and brain tissue recovery of neonatal SD rat with hypoxic ischemic brain injury (HIBI). METHOD: A modified newborn rat model that had a combined hypoxic and ischemic brain injury as described by Rice-Vannucci was used, early nervous reflex, the Morris water maze and walking track analysis were used to evaluate nervous behavioral function, and brain MRI, HE staining to evaluate brain damage recovery. RESULT: Newborn rat Rice-Vannucci model showed significant brain atrophy, obvious hemiplegia of contralateral limbs,e.g right step length [(7.67 ± 0.46) cm vs. (8.22 ± 0.50) cm, F = 1.494] and toe distance [(0.93 ± 0.06) cm vs. (1.12 ± 0.55) cm, F = 0.186] were significantly reduced compared with left side, learning and memory ability was significantly impaired compared with normal control group (P < 0.01); Cliff aversion [(8.44 ± 2.38) s vs.(14.22 ± 5.07) s, t = 4.618] and negative geotaxis reflex time [(7.26 ± 2.00) s vs. (11.76 ± 3.73) s, t = 4.755] on postnatal 14 days of HIBI+ transplantation group were significantly reduced compared with HIBI+NaCl group (P < 0.01) ; the Morris water maze experiment showed escape latency [ (23.11 ± 6.64) s vs. (34.04 ± 12.95) s, t = 3.356] and swimming distance [ (9.12 ± 1.21) cm vs.(12.70 ± 1.53) cm, t = 17.095] of HIBI+transplantation group were significantly reduced compared with those of HIBI+NaCl group (P < 0.01) ; the residual brain volume on postnatal 10 d [ (75.37 ± 4.53)% vs. (67.17 ± 4.08)%, t = -6.017] and 67 d [ (69.05 ± 3.58)% vs.(60.83 ± 3.69)%, t = -7.148]of HIBI+ transplantation group were significantly larger than those of HIBI+NaCl group (P < 0.01); After human UCBMC transplantation, left cortical edema significantly reduced and nerve cell necrosis of HIBI+ transplantation group is not obvious compared with HIBI+NaCl group. CONCLUSION: Human UCBMC intraperitoneal transplantation significantly promoted recovery of injured brain cells and neurobehavioral function development.

[Three-dimensional fluid attenuated inversion recovery imaging at 3T MRI in sudden deafness: its findings and relationship with the prognosis].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 3D FLAIR can show high signal in affected inner ear in sudden deafness patients, and which is related to a poor hearing prognosis.