At present,the graduate teaching of medical imaging and nuclear medicine is still facing many problems,such as paying more attention to the academic research while ignoring ideological and moral reconstruction,teaching arrangement being unreasonable,poor students' clinical practice ability,lack of scientific training system,and no mature evaluation system and so on.Therefore,in clinical teaching ideological and political education is needed as the guide,to enable students to understand the present medical environment,enhance their doctor-patient communication ability.Besides,in the clinical and scientific research ability cultivation,graduate students' learning enthusiasm should be fully mobilized to promote them to actively explore scientific problems.Furthermore the perfect clinical evaluation method and index system should be combined to assess the quality of training.

Objective To investigate the value of 64-slice spiral computed tomography(CT)angiography in preoperative evaluation of spinal vascular intervention.Methods Seventeen patients with segmental injury of the spinal cord underwent the enhanced 64-slice CT scan of the spine.Thin-slice reconstruction was done,with the slice thickness of 0.625 mm and interval of 0.625 mm.The data were transferred to the work station ADW4.2 in DICM format.Image postprocessing technologies such as volume rendering(VR),maximum intensity projection(MIP)and multi-planar reformat(MPR)were used to conduct three-dimensional reconstruction and analyze the anatomical characteristics of radiculomedullary artery.Results Radiculomedullary artery could be found in the thoracolumbar segment of 16 patients(16/17,94%).Among them,one artery(1/17,6%)went into the vertebral canal through the left intervertebral foramen of T4/5,two(2/17,12%)through the left intervertebral foramen of T10/11,one (1/17,6%)through the left intervertebral foramen of T11/12,four(4/17,24%)through the left intervertebral foramen of L1/2,two(2/17,12%)through the left intervertebral foramen of L2/3,two (2/17,12%)through the right intervertebral foramen of T11/12,two(2/17,12%)through the right intervertebral foramen of T12/L1,two(2/17,12%)through the right foramen of L2/3 andl0(10/17,59%)through the left intervertebral foramen.Either CT scan or DSA examination found no radiculomedullary artery in one patient.All the above findings were in accordance with the results of DSA examination.Conclusions Spiral 64-slice CT scan can provide significant preoperative evaluation information for spinal vascular intervention,for it can accurately and visually show the anatomical features of the radiculomedullary artery such as open position,flow tendency,caliber size and spatial relationship with the surrounding vessels.

BACKGROUND: Neural stem cells are always derived from fetal rats and adult rats, and it is complex to isolate the cells by cell culture.OBJECTIVE: To study a convenient and effective method for the isolation and the culture of neural stem cells in neonatal rats.DESIGN, TIME AND SETTING: An observation study based on cells was carried out in the Chongqing Medical University (Chongqing, China) from October 2006 to March 2007.MATERIALS: Wistar neonatal rats of 1-3 days old.METHODS: Subsequent to trypsin digestion, primary culture of the cells was performed in serum-free suspension culture medium. Then the cells were induced to incubate in DMEM/F12 containing 0.10 volume fraction of fetal bovine serum. MAIN OUTCOME MEASURES: Phase contrast microscopy was employed to observe the growth of neural stem cells and the morphology of the differentiated cells. Neural stem cells and the differentiated neurons were identified using indirect immunofluorescence cytochemistry, as well as expression of gilal fibrillary acidic protein. Moreover, the proliferation of the BrdU-labeled neural stem cells was also investigated.RESULTS: The neural stem cells isolated from neonatal rat brains had the potential of serial passage and proliferation, besides, they express neuroepithelial stem cell protein (nestin) and differentiate into neurons, astrocytes and oligodendrocytes.CONCLUSION: Neural stem cells can be harvested from neonatal rat brains at a large scale, and they maintain their undifferentiated features and have the capacity of self-renewal and pluripotentiality.

Purpose To describe the normal appearances of skull on 3D-reconstruction of Multi-slice CT in adult.Materials and Methods 130 patient data of Volume CT digital subtraction angiography (VCTDSA) with cephalocervical and cephalic vessel that were checked at our hospital from May to July 2009 were analyzed.All of them were subjected to 3D reconstruction of the skull by volume render (VR) and maximum intensity projection (MIP).The anatomy of skull,vascular grooves,pacchionian impressions,the types and closure status of cranial sutures were observed.Results 27 pacchionian impressions (20.77%,27/130) and 51 vascular grooves (39.23%,51/130) were detected.There were three types of the general shapes of cranial sutures:Ⅰconventional type(86.15%,112/130),Ⅱfontanelle ossification type(5.38%,7/130) and Ⅲcranial suture within a cranium (8.46%,11/130).Furthermore,Status of each suture closure were divided into five types:typeⅠcomplete closure(3.0%,16/531);typeⅡgomphosis(78.3%,416/531);typeⅢ sutural bone (7.0%,37/531);typeⅣincomplete closure(3.6%,19/531),the average width of non-closed suture was 1.41mm±0.70mm;typeⅤmixed type (8.1%,43/531).Conclusion 3D reconstruction of multi-slice computed tomography is proved to be a reliable technique capable of defining anatomy of skull.Better than MIP to displays three-dimensional structure VR,but to display cranial sutures,vascular grooves,pacchionian impressions MIP is more definite and hypersensitive.Status of each suture closure may be divided into five types,and the general shapes of cranial sutures may be divided into three types.

Objective To assess the clinical value of MRI in evaluation of acute spinal cord in-jury. Methods A total of 50 patients with acute spinal cord injury were examined with magnetic reso-nance (MRI), X-ray and CT. Of all, 15 patients for spinal MR imaging were examined with axial and sngittal spin-echo and fast spin-echo imaging and 17 with coronal imaging. All imaging was performed on 1.5T superconducting system (GE/SIEMENS) with spine surface coil. Results Among 50 patients with acute spinal cord injury, spinal cord edema was detected by MRI in 16 patients, by CT in four but none by X-ray. Intraspinal cord hemorrhage was detected by MRI in 21 patients, by CT in 11 but none by X-ray. Compression and dislocation were detected by MRI in 34 patients, by CT in 15 but none by X-ray. Incomplete and complete transection of spinal cord was found by MRI in 10 patients, by CT in three but none by X-ray. Conclusion MRI is superior to CT scanning and X-ray in detection and evaluation of a-cute spinal cord injury and is the optimal method for examination and diagnosis of acute spinal cord injury.

BACKGROUND: Brain metabolic abnormality can be observed after cerebral ischemia.OBJECTIVE: To observe the changes of biochemical metabolism of rats with focal cerebral ischemia with 1H magnetic resonance spectroscopy (MRS) in order to reflect the metabolite abnormalities of rats during cerebral ischemic recovery phase.DESIGN: Randomized controlled study.SETTING: Departments of Neurology and department of Radiology of First Affiliated Hospital of Chongqing Medical University.MATERIALS: The experiment was conducted at the Radiological Department of First Affiliated Hospital of Chongqing Medical University from April to July 2004. Totally 24 adult Wistar rats with clean grade were randomly divided into three groups, namely: control group, sham operation group and cerebral ischemia group, with 8 rats in each group.METHODS: The focal cerebral ischemic model was established by occluding the right internal carotid artery in cerebral ischemia group and the filament were just inserted into the internal carotid artery not into the middle cerebral artery in sham operation group, nothing was done except for anesthetizing in the control group. 1H MRS was performed within the area of cerebral infarction and the homologous area of the contralateral hemisphere using 1.5T GE signa Highspeed MRI spectrometer in cerebral ischemic and shamed operation group at the following time point of 30 minutes, 1, 3, 6, 12, 24 hours, 3, 7, 15 days, 1 and 2 months after cerebral ischemia, and in the control group at the same time point.MAIN OUTCOME MEASURES: Changes of lactate, N-acetyl-aspartate (NAA), choline and creatine in infarct hemisphere and contralateral hemisphere.RESULTS: Totally 24 rats were selected in the study, but two died of anesthesia in sham operation group and four of serious brain edema in cerebral ischemia group, only 18 rats entered the final analysis with 8 in normal control group, 6 in sham operation group and 4 in cerebral isThe marked increase in NAA, choline and creatine was recognizable in bilateral spectra 30 minutes after cerebral ischemia and decreased to the period of 3-6 hours, but there was no significant difference in NAA, choline at 6 hours and reached the lowest level at 24 hours (45.21±0.37), choline (93.80±0.56) and creatine (69.33±0.44) at 3 days, and then NAA, choline and creatine gradually increased over time. The increase in NAA was especially obvious which increased by 2.5 times at 2 months than that at 24The earliest detection of lactate was at 10 minutes within the infarct. The lactate concentration elevated at 1 day and peaked at 12 hours, and a partial recovery of the reduction of lactate was seen at 3 days, and the lactate increase within the infarct region was significant compared with that of the homologous area (66.83±0.43,44.35±0.35, t=2.379, P ＜ 0.05). However, the elevation in lactate was no longer observed during the period of up to 2month follow-up.ischemia and reflect the metabolites changes in brain of rats after cerebral cerebral ischemic recovery phase objectively.

ObjectiveTo explore the values of 3D enhanced T2-star weighted angiography (ESWAN) in detecting iron deposition of the brain in patients with multiple sclerosis ( MS).Methods Conventional MRI and 3D ESWAN were performed in 22 patients with released-remitting MS(RR-MS) and in 22 age- and gender-matched normal controls.Both the magnitude images and phase images were available after post processing of the original ESWAN data post processing.The expanded disability status scale (EDSS) scores of the patients were from 0 to 8.5,and the course of disease were between 0.5 year and 15 years.The manifestation of MS lesions was evaluated on conventional MR images and ESWAN images by two experienced radiologists with blind methods.The phase values were measured for MS lesions between the semioval center and periventricular white matter and the corresponding regions in the normal control group were measured as well The Wilcoxon rank test was used to compare the differences of phase values between MS patients and normal controls,and the Spearman rank correlation analysis were used to analyze the correlations among the phase values of MS lesions,EDSS scores and course of disease of MS patients.Results( 1 ) MS lesions were observed on magnitude images and phase images,respectively and together.Two hundred and thirteen(32.8％ )lesions were detected on both the magnitude images and phase images,164 (25.2％)lesions were detected on the magnitude images only,and 273 (42.0％) lesions were detected on the phase images only.A total of 650 lesions were observed on the ESWAN,which showed more 42 lesions than conventional images(608).Among 486(273 + 213 )lesions observed on the phase images,205 (31.5％) lesions were homogeneously hypointense,45 (6.9％ ) lesions showed hypointense ring,and 236 (36.4％ ) lesions were inhomogeneously hypointense.(2) “ Penetrating veins” were showed in 424 (65.2％ ) periventricular lesions.The “penetrating veins” showed dilated and prolonged in 198 (30.5％ ) acute lesions,thin and short in 208 (32.9％ ) chronic lesions.However,the “penetrating veins” of 12 ( 1.8％ ) chronic lesions in 5 stable MS patients were expanded and prolonged slightly.( 3 ) The average phase value of the lesions ( - 0.05 ± 0.08) in patients with RR-MS was significantly lower than that of corresponding to regions (0.06 ± 0.05 ) in the normal control group( Z = 22.30,P ＜ 0.01 ).(4) The phase values of MS lesions were significantly correlated to the EDSS and course of disease of patients with RR-MS (r = -0.98,0.99 respectively,P ＜ 0.01 ).ConclusionESWAN can be helpful in the evaluation and quantification of abnormal iron deposition in MS lesions,which provides important values for the pathogenesis and pathological study for MS patients.

BACKGROUND: At present, traditional modalities of neuroimaging, such as CT and MRI, is very limited in the diagnosis and severity estimation of diffuse axonal injury (DAI).OBJECTIVE: To investigate the value of proton magnetic resonance spectroscopy (1HMRS) in the diagnosis and prognosis of DAI.DESIGN, TIME AND SETTING: Prospective clinical controlled observation. The study was performed at the Department of Neurosurgery, and Department of Radiology, First Affiliated Hospital of Chongqing Medical University between October 2002 and September 2007.PARTICIPANTS: A total of 63 subjects with traumatic brain injury were enrolled and divided into DAI group (n=27) and non-DAI group (n=36) according to the result of MRI. In addition, 20 healthy persons were served as control group.METHODS: Demographic and clinical data were recorded on admission and neuroimaging examinations including fluid attenuated inversion recovery were carried on according to carefully designed procedures, in addition, 1HMRS was performed and the data were analyzed in combination with clinical condition.MAIN OUTCOME MEASURES: The ratios of N-acetyl aspartate (NAA)/creatine (Cr) and creatine phosphate (Cr), Choline compound (Cho)/Cr, myoinositol (mlNs)/Cr, and glutamic acid (GIx)/Cr at genu and splenium of corpus cellosum, and basal ganglia were quantified using 1HMRS.RESULTS: Compared with control and non-DAI groups, DAI group had decreased NAA/Cr and increased Cho/Cr at genu and splenium of corpus callosum, and basal ganglia (P < 0.05- 0.01), as well as increased mlNs/Cr and Glx/Cr at genu and splenium of corpus cellosum (P < 0.05). Non-DAI group also showed decreased NAA/Cr at splenium and increased Cho/Cr at genu of corpus callosum compared with control group (P < 0.01), but the change degree was less than DAI group. A positive correlation between Cho/Cr at genu of corpus callosum and the peded of primary unconsciousness was identified in DAI group (r=0.824, P < 0.01). CONCLUSION: The 1HMRS indexes at genu and splenium of corpus callosum, and basal ganglia could serve as effective indexes for the diagnosis of DAI. The Cho/Cr could well reflect histological changes following injury and act as sensitive index to predict clinical injury.

Objective To explore the values of diffusion-weighted imaging(DWI)and apparent diffusion coefficient(ADC)measurements in various lesions of multiple sclerosis(MS).Methods Sixty patients with clinically diagnosed remitting-relapsing MS(RRMS)were included to undergo conventional brain MRI and DWI scans.the lesions were included when the diameter was more than 5 mm.mean ADC values were measured for various lesions of MS.The statistical analyses were performed to determine the differences of mean ADC values among various lesions of MS.and to compare the correlation between ADC values of lesions and Expanded Disability Status Scale(EDSS)scores.Results (1)The ADC value of hypointense lesions was significantly higher than that of isointense lesions(F=55.90,P<0.05),the ADC values were(127.5 ±9.3)×10-5mm2/s and(95.7 ±6.3)×10-5mm/s respectively.The nodular enhancing lesions had a significantly lower ADC value than the ring-enhancing lesions(F=64.18,P<0.01).the ADC values were(114.7 ±12.3)×10-5mm2/s and(140.7 ±11.0)×10-5mm2/s respectively.The ADC value of confluent lesions was substantially higher that of discrete lesions(t=9.04,P<0.01).the ADC values were(141.4±6.5)×10-5mm2/s and(105.4±13.9)×10-5mm2/s respectively.(2)No correlation between ADC of lesions and EDSS scores was found(r=0.35,P>0.05).Conclusion DWI and quantitative ADC are useful to explain the pathological changes in different lesions and to monitor the disease duration of MS.

Objective To investigate the brain magnetic resonance imaging(MRI)findings in 33 patients with neuromyelitis optica(NMO).Methods Patients who fulfilled the latest diagnostic criteria of NMO and whose brain MRI did not satisfied with diagnostic criteria of multiple sclerosis(MS)were enrolled.All the patients underwent brain MRI and spinal cord scannings and subsequent images analysis.Results Thirty-three patients with NMO were included to study.Five out of 33(15.2%)patients did not have brain parenchymal abnormalities,28 out of 33 patients(84.8%)were detected to have brain abnormal findings.Brain parenchymal lesions were well-defined in 22 patients(66.7%),no non-specific or atypical brain parenchymal lesions were found in the supratentorium or infratentorium in the other 6 cases(18.2%).However,brain MRI disclosed macroscopic,symmetrical diffuse FLAIR and T2-visible hyperintensity in deep white matter.Fifteen cases had more than one lesion(≥2 lesions),and the other 7 cases had single lesion.Supratentorial lesions were mostly punctate or small dots in nonspecific hyperintensity in juxtacortical,subcortical and deep white matter regions,a few were atypical patches.In the infratentorium,brainstem was an easily involved region(14/33,42.4%),especially in medulla(7/33,21.2%).Conclusions Brain MRI abnormalities are common in Chinese NMO,and brain lesions do not exclude the diagnosis of NMO.The observations of brain lesions are helpful to improve and revise diagnostic criteria of NMO.