Objective To examine the feasibility by applying the CT density-difference postprocessing in early diagnosis of middle cerebral artery (MCA) occlusion. Methods The possible MCA occlusion patients were scanned with CT in early stage (within 3 hours) and divided into two groups randomly.Each group included 50 samples and one was processed technologically by CT density-difference and the other one was not.The two groups were scanned once more in 24 hours later and the data being processed by statistical method. Results The results showed that the accurate diagnosis rates were 14.3% within 60 minutes,93.3% from 60 to 119 minutes and 100% from 120 to 180 minutes .In comparing these two groups,there appeared no significant differences in the situation within 60 minutes and there was found significant difference in the other two situations. Conclusion Applying the technology of CT density-difference postprocessing,the middle cerebral artery (MCA) occlusion in early stage might be diagnosed.

The deterioration of indoor air quality (IAQ) in medical district was caused by the personnel in the area, the buildings and their surroundings, and the situations of the air conditioning system. It is necessary to control the personnel entering the medical area and to strengthen the management of the buildings and their surroundings, and the air conditioning system for maintaining high IAQ. The development of new efficient air cleaning (equipment) is of importance in the same way.

Objective To investigate the clinical and characteristic imaging findings of intracranial gliosarcoma. Methods The imaging findings of surgery and pathology proved intracranial gliosarcoma in 15 cases were retrospectively analyzed. There were 10 males and 5 females, ranging in age from 44 to 67 years (mean age 58 years). Results All tumors were located in supratentorium, including 13 cases in the temporal or parietal lobe, 1 cases in the occipital lobe, and 1 cases in the thalamus. Tumors appeared as round or ellipse in shape. The lesions ranged in size from 3 to 9 cm (mean 4.6 cm). CT scan showed mingled hypo and isodensity in 7, hypodense in 4 with CT value from 18 to 22 HU, hyperdense in 4 with the CT value from 48 to 55 HU. Enhancement appeared as an irregular pattern. The margin was clear. Most intracranial gliosarcoma showed perifocal edema. MRI were examined in 6 cases, whichappeared as low signal on T 1WI, and as high signal on T 2WI. There was irregular enhancement of the mass. Conclusion It was difficult to make the correct preoperative diagnosis for gliosarcoma, but it was possible to make a tendency diagnosis using CT or MR combined with the history. Contrast enhanced CT and MRI should be useful in differentiating gliosarcoma from glioblastoma.

Objective To investigate the characteristic clinical, imaging, and pathologic findings of intracranial neuronal and mixed neuronal-glial tumours. Methods The imaging findings of surgery and pathobiology proved intracranial neuronal and mixed neuronal-glial tumours in 14 cases (7 male and 7 female, ranging in age from 6-56 years; mean age 33.8 years) were retrospectively analyzed. Results Eight gangliogliomas were located in the frontal lobe (4 cases), temporal lobe (1 case),fronto- temporal lobe(2 cases), and pons (1 case). They appeared as iso-or low density on CT, iso-or low signal intensity on T 1WI, and high signal intensity on T 2WI on MR imaging. Two central neurocytomas were located in the supratentorial ventricles. Four desmoplastic gangliogliomas were seen as cystic masses, appearing as low signal intensity on T 1WI and high signal intensity on T 2WI Conclusion Intracranial neuronal and mixed neuronal-glial tumours had imaging characteristics. Combined with clinical history, it was possible to make a tendency preoperative diagnosis using CT or MR.

Objective To establish the median equation of second trimester Down′s syndrome (DS) screening maternal serum markers ,alpha-fetoprotein (AFP) and human chorionic gonadotrophin (HCG) ,in Xiangxi area and to investigate the influence of new median values on the local screening results .Methods The electrochemiluminescence immunoassay (ECLIA ) was applied to detect the serum AFP and HCG levels in 2619 second-trimester normal pregnant women ,the medians of AFP and HCG in each gestational week were calculated ,and the regression equation between gestational period and the medians of AFP and HCG were es-tablished by using the statistical software ,then the results were compared with the evaluation results of software built-in medians . Results Serum AFP level was positively correlated with the gestational week (P<0 .01) ,the HCG level was negatively correlated with the gestational week (P< 0 .01);the AFP and HCG levels were negatively correlated with the body weight of pregnant woman (P<0 .01) .Before correcting the body weight ,compared with software built-in human source serum markers ,the average levels of serum AFP and HCG in Xiangxi area increased by 6 .73% and 31 .54% respectively ,the differences were statistically sig-nificant ,after correcting the software ,the screening false positive rate was remarkably decreased .Conclusion The establishment of serum maker medians for second trimester pregnant woman in Xiangxi area can increase the efficiency of the second trimester DS screening ,thus effectively screens out the DS fetus in local area .

Objective To study CT and MRI features of intracranial chondrosarcomas. Methods CT and MRI of 3 cases with intracranial chondros arcomas proved by pathology were retrospectively analyzed.Results CT scans showed the tumors were lobular mass, per itumoral edema were not serious, intratumorous calcification and bone invasion w ere seen in 2 cases.MRI showed that tumor had low to intermediate signal intensi ty or hypointensity on T 1WI, high signal intensity on T 2WI. On contrast enha nced MRI,the center of lesions which was low signal intensity on T 2WI was no e nhancement, but there was observable enhancement at periphery of tumors.Conclusion Intracranical chondrosarcomas are often orgina ted from synchondrosis of the skull base,the lesions are often associated with c alcification, and bone invasion, the accurate dignosis should depend on microsco pic examination and immunohistochemical staining.

Objective To analyse imaging features of atypical meningioma.Methods There were 17 cases with atypical meningiomas proved by pathology,7 cases were male,10 cases were female,ranged in age from 34～69 years.17 cases all examined with CT,and 10 cases with CT enhanced scanning;12 cases examined with MRI and 8 cases with MR enhanced scanning,5 cases examined with DSA.Results The major imaging features of atypical meningioma included:the borders of tumors were mostly irregular,nonhomogeneous density or signal on plain CT and MRI,nonhomogeneous enhancement on enhanced CT and MRI.Cystic and necrotic changing and the invasion of cranial bone and adjacent structure could be seen.5 cases with dural tail sign on MRI,3 of them,this sign was short,thick and irregular.Heavy staining was showed on DSA.Conclusion Atypical meningiomas are of some clinical and imaging features.

Objective To study the clinical law and imaging characteristics of intracranial primary malignant lymphoma.Methods The clinical law and imaging finding in 27 cases of intracranial primary malignant lymphoma confirmed by pathology were analysed CT scan was performed in all cases.MRI examination were carried out in 20 cases simultaneously.Results The first symptom in most cases was headache,and other symptoms were epileopsy,dizziness,hemiplegia,etc.This lesion was mostly seen in male around 40 years old.The lesions were mostly equal or high density on CT,equal or low signal intensity on T 1WI and closed to grey matter signal intensity on T 2WI.Tumors were enhanced obviously on contrast-enhanced scans,necrosis of center of focus was seen in 1/3 cases.The lesions were single or multiple.Conclusion The accuray diagnosis of intracranial primary malignant lymphoma can be done by combined clinical data with imaging features.

AIMTo study the protective effect of sodium oxybate (SO) against focal cerebral ischemia-reperfusion injury in rats, and the relationship between the effects of SO and ?-aminobutyric acid (GABA). METHODSThe reversible middle cerebral artery occlusion (MCAO)model in rats was established to investigate the role of SO. The scores of neurological deficits was detected by Longa EZ method in MCAO rats. The extracellular levels of glutamate (Glu) and GABA in CSF were measured by high performance liquid chromatography-fluorometer (HPLC-FR) method, and the weight of cerebral infraction was detected. RESULTSThe scores of neurological deficits and the weight of cerebral infraction markedly decreased by SO while the ratio of GABA/Glu obviously increased administered SO in MCAO rats. CONCLUSIONSSO could prevent MCAO rats from ischemia-reperfusion injury, the protective effect is related to SO keeping dynamic balance of excition-inhibition, and persisting inhibition-depended effect.

Objective To explore the technique and the clinical value of Neuroform stents in combination with Guglielmi detachable coil(GDC) to treat wide-necked basilar artery aneurysms.Methods 30 cases with wide-necked basilar artery aneurysms were treated with Neuroform stent combined with GDC.Of 30 wide-necked basilar artery aneurysms,the location of lesions was at basilar tip in 16,basilar trunk in 9 and the beginning of the basilar in 5.Results In 30 cases,total occlusion was achieved in 25 and partial occlusion in 5 patients.The thrombosis within stent occurred in 2 patinets,and remainder of patients recovered well.There were no thromboembolic events in 20 cases followed up for 3~6 months.Twenty-two patients were angiographically followed up for 3 months after the procedure,among them,the aneurysms visualized and the arteriae burdened aneurysms were passed free in densely packed and 3 aneurysms with neck remnant.Conclusion The Neuroform stent is a easy and safe intracranial stent for embo1ization of wide-necked intracranial aneurysms,especially suitable for wide-necked basilar artery aneurysms with severely tortuous intracranial artery.