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Xue-lin Zhang

Publications and source records attributed to Xue-lin Zhang.

17 recordsLinked to original sources
PubMed2006

[Quantitative study of dynamic magnetic resonance perfusion-weighted imaging in rabbit models of implanted hepatic VX2 tumor].

OBJECTIVE: To investigate the possibility of dynamic magnetic resonance (MR) perfusion-weighted imaging (PWI) in rabbit models of implanted hepatic VX2 tumor. METHODS: MRI and PWI images were obtained from 16 rabbit models of implanted hepatic VX2 tumor and 4 normal rabbits at 14, 18, 22, and 26 days after tumor implantation, respectively, and the mean time to enhancement (MTE) and maximum slope of increase (MSI) were estimated and compared with pathological changes. RESULTS: In the rabbit models of implanted hepatic tumor the MTE tended to increase and MSI to descend 14, 18, 22, and 26 days after tumor implantation, showing significant differences from the control group. Coagulation necrosis and fibrous hyperplasia in the tumors appeared to progress with time as found pathologically. CONCLUSION: Dynamic MR PWI quantitative analysis of rabbit models of implanted hepatic VX2 tumor provides valuable means for observing the growth behaviors of VX2 tumor and may be clinically applicable in the evaluation of hepatic diseases.

Animals↗
PubMed2006

[Application of 16-slice spiral CT angiography in aortic dissection].

OBJECTIVE: To explore the value of 16-slice spiral CT angiography in the diagnosis of aortic dissection (AD). METHODS: Twenty patients with AD underwent 16-slice spiral CT angiography with multi-planar reformation (MPR), curved planar reformation (CPR), maximum intensity projection (MIP), volume rendering (VR) and CT virtual endoscopy (CTVE). All the original and reconstructed images were studied. RESULTS: The original transverse axial images most reliably preserved the fundamental information. The reconstructed images gave better performance in displaying the spatial relation between the blood vessels and the lesions. Images obtained by different reconstruction methods had different characteristics, and combining different display modes allowed clear representation of the features of aortic dissection such as the extension of the lesion, true and false cavity, disrepair of the intimal flap, aortal branch involvement, thrombi and outcome of endoluminal stenting. CONCLUSION: Multislice spiral CT angiography can fully display the details of aortic dissection and is therefore of important value for the diagnosis and preoperative and postoperative evaluations.

Adult↗
PubMed2006

[Modification of the method for preparing rabbit liver VX2 tumor model and its MRI findings].

OBJECTIVE: To improve the method for preparing rabbit VX2 liver tumor model and observe the magnetic resonance imaging (MRI) features of the implanted tumors. METHODS: Sixteen adult New Zealand white rabbits were assigned randomly into 4 equal groups, and VX2 tumor tissues were implanted into the right and left liver lobes with spiral CT guidance. Plain and contrast-enhanced MR scan and pathological analysis were performed in different stages (14, 18, 22 and 26 days) after tumor implantation. RESULTS: Tumor implantation was successful in all the rabbits, and 18 to 22 days after tumor implantation, the diameters of the tumor ranged from 1 to 2 cm, which allowed observation and study. In plain MR scans, lower or equivalent tumor signal in comparison with hepatic parenchyma was observed, and contrast-enhanced scans produced obvious enhancement of the tumor edges. At 22 days after tumor implantation, obvious necrosis was observed in the center of the tumor. CONCLUSION: This method of preparing rabbit VX2 liver tumor model with spiral CT guidance is simple and convenient, and the tumors can be observed effectively with dynamic plain and contrast-enhanced MR scans.

Animals↗
PubMed2006

Clinical value of pre-and postoperative 18F-FDG PET/CT in patients undergoing liver transplantation for hepatocellular carcinoma.

OBJECTIVE: To assess the clinical value of fluorine-18-2-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron-emission tomography/computed tomography (PET/CT) in preoperative evaluation of hepatocellular carcinoma (HCC) patients for liver transplantation and in early detection of recurrent foci after the operation. METHODS: A retrospective study was conducted involving 19 HCC patients undergoing (18)F-FDG PET/CT before and after liver transplantation. The pre- and postoperative clinical data and (18)F-FDG PET/CT images of these patients were analyzed. Totally 10 (18)F-FDG PET/CT examinations (in 8 patients) were performed for purpose of preoperative evaluation of the transplantation and assessment of the tumor elimination and general metastasis following the adjuvant therapy, and 22 examinations (in 11 patients) performed postoperatively to identify recurrent foci and metastasis. The average time span between (18)F-FDG PET/CT examination and the operations was 8.68 months. RESULTS: PET examinations in 2 patients for preoperative evaluations showed no evidence of tumor recurrence or metastasis, so they underwent liver transplantation as scheduled. (18)F-FDG PET/CT found distinct metastasis in the target operation area in another 2 patients, and liver transplantation was performed with proper management of the metastatic foci. The other 4 patients were found to have distal metastasis, so that operations were cancelled and the patients received interventional therapy and other treatments instead. Postoperative (18)F-FDG PET/CT examination discovered no metastatic foci in 2 patients, but detected mycotic brain abscess in 1 patient. Another 19 postoperative (18)F-FDG PET/CT examinations (in 8 patients) showed recurrence in the grafted liver (in 4 patients), tumor embolism in the left and right hepatic veins and in the inferior vena cava, in addition to metastasis to the lungs, lymph nodes, bone, spleen, parietal pleura, intervertebral foramen of the thoracic vertebra etc. CONCLUSION: (18)F-FDG PET/CT scanning shows superior accuracy in identification of lymph node tumor metastasis. With the advantages of whole-body scanning and high sensitivity of tumor detection, (18)F-FDG PET/CT can be instrumental in preoperative evaluation of liver transplantation for HCC (such as modification of the clinical staging) and postoperative early detection of recurrent tumors.

Carcinoma, Hepatocellular↗
PubMed2006

Phase-contrast magnetic resonance angiography for assessment of intracranial venous sinus lesions.

OBJECTIVE: To review the presentations of intracranial venous sinus lesions in phase-contrast (PC) magnetic resonance angiography (MRA) and discuss the diagnostic value of this imaging modality for these lesions. METHODS: This study involved 52 patients with intracranial venous sinus lesions, including 21 with dural venous sinus malformation, 7 dural arteriovenous fistula (6 caroticocaveneous fistula, CCF), 5 venous sinus thrombus and 19 meningioma invading the venous sinuses. All patients underwent PC and time-of-flight (TOF) MRA with a 1.5 Tesla MR scanner, with 28 of them undergoing subsequent digital subtraction angiography (DSA). RESULTS: PC MRA showed extensive hyperintense signals that identified the lesions, feeding arteries, deferent veins and venous sinuses in 21 cases of dural arteriovenous fistula, but the lesion signals appeared homogeneous. In these cases, PC and TOF MRA had equally good performance in displaying the feeding arteries with success in 20 of the 21 cases (95.2%), whereas the former resulted in a greater rate of deferent vein display [90.5% (19/21)] than the latter [76.2% (16/21), P<0.05]. The 6 CCF cases showed ipsilateral cavernous sinus expansion and upper ophthalmic vein dilations. In the 5 cases of venous sinus thrombis, 4 had transverse sinus thrombus and 1 superior sagittal sinus thrombus. All the cases presented signal disappearance in the sinuses in PC MRA and hyperintense signals in MRI, and some cases had also cerebral superficial hemorrhage and edema. The 19 cases of meningioma invading the venous sinus displayed sinus shift, stenosis and occlusion in PC MRA. CONCLUSION: PC MRA has great advantages in displaying the anatomical structure and lesions of the venous sinuses.

Adolescent↗
PubMed2005

[Clinical and imaging diagnosis of primary hepatic lymphoma].

OBJECTIVE: To investigate the clinical and imaging features of primary hepatic lymphoma (PHL). METHODS: Four PHL cases were analyzed retrospectively for clinical manifestations, transcatheter hepatic arterial angiography and CT features. RESULTS: All the four cases were B-cell non-Hodgkin lymphoma proven by histological and immunohistochemical examination. The main clinical manifestations included pain in the right upper quadrant and B symptoms of the lymphoma (fever, night sweating, and weight loss) in 3 patients. Three cases were complicated by chronic hepatitis or cirrhosis, and the other had renal transplantation two years ago. All these cases exhibited elevated serum lactate dehydrogenase (LDH) level, which was reduced after surgery or chemotherapy. Plain CT scan all identified hypodense lesions which did not display marked enhancement on the arterial phase and portal venous phase scans. On delayed phase scan, the border of the lesions became clear, and slight enhancement was observed in the peripheral and some partitions of the lesions. Angiographic imaging displayed slight tumor staining and arterial displacement in the liver in all the cases with thin tumor-supplying vessels. Global staining or abnormally thickened vessels were not seen. CONCLUSION: A comprehensive evaluation of the clinical manifestations and imaging features can be helpful in the diagnosis of PHL, and serum LDH level may help to assess the therapeutic effect.

Adult↗
PubMed2005

[Value of multislice spiral CT scanning and three-dimensional reconstruction in selecting optimal length and shape of mandible internal fixation material].

OBJECTIVE: To investigate the value of multislice spiral CT (MSCT) scanning and three-dimensional reconstruction in selecting optimal length and shape of mandible internal fixation material. METHODS: Three-dimensional reconstruction of the mandible was performed in 5 cases by MSCT scanning and the length of the mandible for operation was measured. Some isometric points were chosen on the mandibular curve and the distance from these points to the two ends of the curve was measured to depict the mandibular curve using a self-designed skeletal curve-depicting software. The optimal length and shape of the material for internal fixation was then determined. RESULTS: After removal of the soft tissues and other irrelevant bones from the reconstructed three-dimensional mandible with clear view from any directions, the length of the mandible was accurately measured with the software. The physiological curve of the mandible was generated after determination of the distances from the chosen points on the mandibular curve and to the two ends of the curve for precise determination of the length and shape of the material for internal fixation. CONCLUSION: Three-dimensional mandible reconstruction with MSCT and measurement facilitates the determination of the optimal length and shape of the internal fixation material to enhance the attachment between the material and the bone surface and consequently the therapeutic effects.

Adolescent↗
PubMed2005

[Influence of soil lead upon children blood lead in Shenyang City].

The dynamic correlation coefficients between soil lead and blood lead, the children blood lead arose from soil lead and the length of time over which the blood lead concentration can fall to be at or below the threshold value (10 microg x dL(-1)) are analyzed. If the aggregated soil lead and blood lead are stratified by the seven geographic regions studied, an elevated R of 0.9200 could be calculated, and the lead exposure assessment may require knowledge of geographic dimension of the exposure topology components. The children blood lead levels calculated based on the soil lead in the unit of geographic region show that the blood lead levels of about 90% of children exceed the threshold value in the west industrial area, while they are all below the threshold value in the east area. The children, whose blood lead level exceed the threshold value, are in the range of 3.48% - 31.81% in the other areas. The length of time over which the blood lead concentration can fall to be at or below the threshold value is highest, and average 26.68months, in the west area, and the order is the west > the north > the northeast > the southwest > the northwest > central area > the east, it is zero in the east area, and the maximum recovery time follow the same order. The blood lead levels and the recovery time are controlled by the environmental lead contamination, and the lead hazard intervention would contribute to the fall of blood lead levels.

Child↗
PubMed2004

Perfusion homogeneity of hepatic parenchyma in magnetic resonance imaging during splenoportography.

OBJECTIVE: To evaluate the homogeneity of hepatic parenchyma enhancement in magnetic resonance imaging during splenoportography (MRSP) in the portal phase. METHODS: MRSP was performed in 16 patients suspected of space-occupying lesions in the livers. The signal intensity of non-lesion abnormal perfusion areas and that of peripheral parenchyma were measured in all the scanning phases including unenhanced phase, portographic phase, equilibrium phase, and delayed phase. RESULTS: Perfusion abnormalities were observed in 8 non-lesion foci in the portal phase in 4 cases of hepatic cirrhosis, most frequently appearing in triangle or fan-like shapes (7/8) with unpredictable locations. Hepatic cirrhosis patients had more non-lesion perfusion abnormalities than non-cirrhosis patients. CONCLUSIONS: The presence of non-lesion perfusion abnormalities in MRSP does not affect the diagnosis of the disease, and more homogeneous enhancement of the hepatic parenchyma in the portal phase can be achieved in MRSP than in CT during arterial portography and magnetic resonance imaging during arterial portography.

Adult↗
PubMed2004

[Diagnosis of intramedullary spinal cord ependymomas and astrocytomas using magnetic resonance imaging: analysis of 15 cases].

OBJECTIVE: To evaluate the magnetic resonance imaging (MRI) features of intramedullary spinal cord ependymomas(INSE) and astrocytomas. METHODS: Retrospective analyses of the MRI images were conducted in 15 cases of INSE and 10 cases of astrocytoma. RESULTS: MRI appearances were similar in the 2 types of neoplasms, both showing enlargement of the involved spinal cord segments, low signal and blurred boundary on T1-weighted imaging, and high signal on T2-weighted imaging. Peritumoral cyst formation were found in 16 patients. Contrast enhancement was homogeneous in 6 cases of ependymomas and 1 of astrocytoma, heterogeneous in 1 astrocytoma case, and no enhancement in 2 astrocytoma cases. CONCLUSION: MRI is helpful in the diagnosis and differential diagnosis of INSE and astrocytomas.

Adolescent↗
PubMed2004

[18F-FDG positron emission tomography for mediastinal staging of lung cancer].

OBJECTIVE: To evaluate the diagnostic value of (18)F-FDG positron emission tomography (PET) in mediastinal staging of lung cancer. METHOD: A retrospective analysis of mediastinal staging was carried out in 41 cases of lung cancer by comparing the preoperative mediastinal FDG PET and CT findings with the pathological results. RESULTS: According to the pathological results, 18 patients had mediastinal metastasis, 17 of whom were correctly identified by FDG PET, and 10 by CT. Of the other 23 patients without mediastinal metastasis pathologically, 22 were correctly diagnosed by FDG PET and 20 by CT. The sensitivity and accuracy for diagnosis of regional mediastinal lymph node metastasis with FDG PET were 94.4% and 95.1%, obviously higher than those of CT (55.6% and 73.2%, P<0.05). CONCLUSION: FDG PET is a better alternative for mediastinal staging of lung cancer, specially for identification of small lymph node metastasis escaping detection by CT, to provide important evidence for clinical staging and treatment planning of lung cancer.

Adenocarcinoma↗
PubMed2004

[Correlation between age and average apparent diffusion coefficient in normal-appearing cerebral white matter].

OBJECTIVE: To quantitatively study the effect of ages on the average apparent diffusion coefficient (ADCav) of normal-appearing white matter. METHODS: Fifty patients with normal-appearing white matter were divided into four age groups, namely 16-30 years, (n=13), 31-45 years (n=12), 46-60 years (n=14) and >60 years (n=11). All the subjects were examined with conventional and trace-weighted diffusion imaging in three orthogonal directions. The ADCav of the white matter was measured and compared between various age groups. RESULTS: In the white matter, the ADCav of all the patients was (0.71+/-0.08) x 10(-3) mm2/s; the ADCav of the white matter in the first to fourth age groups were (0.69+/-0.06) x 10(-3) mm2/s, (0.71+/-0.07) x 10(-3) mm2/s, (0.71+/-0.09) x 10(-3) mm2/s, and (0.73+/-0.10) x 10(-3) mm2/s respectively. ADCav of patients between 16-30 years was significantly different from that of patients over 60 years of age (P=0.014). Patients older than 60 years had an ADCav of the white matter significantly higher than the value of (0.70+/-0.07) x 10(-3) mm2)/s in the total patients younger than 60 years (P=0.026). CONCLUSION: Water diffusibility shows a slight increase in human white matter with aging, possibly due to mild ultrastructural changes associated with aging.

Adolescent↗
PubMed2003

[Comparative study of four GRE sequences in MnDPDP-enhanced magnetic resonance imaging for primary hepatocellular carcinoma].

OBJECTIVE: To assess the value of four T(1)-weighted (T(1)W) gradient-recalled-echo (GRE) sequences in MnDPDP-enhanced magnetic resonance imaging (MRI) for diagnosing primary hepatocellular carcinoma (HCC). METHODS: T(1)W images of fast low-angle shot (FLASH), fat-suppressed (FS) FLASH, in-phase and opposed-phase (IP/OP) FLASH were obtained from 13 HCC patients before and 30 min after the patients were given 5 micromol/kg.b.w. MnDPDP. The delayed (24 h) images were also obtained with the same sequences in addition to the T(2)W turbo spin-echo (TSE) sequence performed before MnDPDP administration. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the liver parenchyma and the tumor foci were calculated for each sequence. RESULTS: No statistical differences were found in SNR and CNR between the images obtained with the four T(1)W sequences (P > 0.05). The fatty degeneration of HCC could be detected by OP imaging, but not by T(1)W FLASH or IP T(1)W imaging. CONCLUSION: IP and OP FLASH produces better and easier performance in characterizing the fatty degeneration of HCC, and are recommended for MnDPDP-enhanced MRI of HCC.

Adult↗
PubMed2003

[MRI features of 13 cases of intracranial ependymoma].

OBJECTIVE: To improve the accuracy of qualitative diagnosis of intracranial ependymomas by analyzing their magnetic resonance (MR) images. METHODS: The MR images of 13 cases of intracranial ependymomas confirmed by pathological examinations were investigated retrospectively. RESULTS: In the 10 cases of ventricle ependymomas, the tumors were identified in the fourth ventricle in 3 cases and in the lateral ventricle in 7 cases. The T(1)-weighted MR images presented isointense or hypointense signals and T(2)-weighted images showed inhomogeneous hyperintense ones. No edema occurred around these tumors, and the contrast-enhanced scans presented inhomogeneous enhancement. In the other 3 cases of ependymomas in the brain parenchyma, including 2 cases of supratentorial and 1 subtentorial ependymomas. The tumor parenchyma presented hypointense signals in T(1)-weighted MR images as compared to the signals of the brain parenchyma, and in T(2)-weighted images, the signals intensities were similar to or higher than those of the gray matter. Mild edema could be seen around the tumors. Enhanced scans of the tumor parenchyma showed mild to moderate enhancement. CONCLUSION: MR examination may help in the preoperative detection of intracranial ependymomas.

Adolescent↗
PubMed2002

[Diagnosis of lesions in the major abdominal blood vessels by three-dimensional dynamic contrast-enhanced magnetic resonance angiography].

OBJECTIVE: To elucidate the working principles of three-dimensional dynamic contrast-enhanced magnetic resonance angiography(3D DCE-MRA)and assess its value in the diagnosis of lesions in the major abdominal blood vessels. METHODS: The imaging data of 3D DCE-MRA and conventional MR examination in 32 cases of suspected major abdominal blood vessel diseases were obtained and analyzed retrospectively. RESULTS: The peak flow of contrast agents through the abdominal aorta at the level of renal artery occurred 17 to 23 s after the injections. Normal presentation was found in 3 cases, with clear images of the abdominal aorta and its branches. Abdominal aortic aneurysm was identified in 7 cases, where the involved segment of the aorta was irregularly broadened and the actual lumen of the abdominal aorta was displayed. Aortic dissection was found in 18 cases, and the intima, the double-lumen, and the position where the abdominal aortic branches originated could be seen with 12 entry sites and 16 re-entry sites. Atherosclerosis was found in 3 cases, with tortuous abdominal aorta whose lumen was morphologically irregular. One case was found with thrombosis in the left iliac vein which was not visualized. CONCLUSIONS: 3D DCE-MRA is a non-invasive alternative for conventional angiography and has significant importance in the diagnosis of lesions in major abdominal blood vessels.

Adult↗