Purpose It has been demonstrated that hepatocytes uptake of Gd-EOB-DTPA obviously decreased,which would result in decreased liver-to-lesion contrast.Therefore,this study was to evaluate the potential of increasing flip angle to improve the image quality of Gd-EOB-DTPA enhanced MR.Materials and Methods A total of 114 patients with focal liver lesions (FLLs),who underwent Gd-EOB-DTPA-enhanced MR of the liver,were enrolled in this retrospective study.39 patients were noncirrhotic group,36 patients were Child-Pugh A group,23 patients were Child-Pugh B group,and 16 patients were ChildPugh C group.Tl-weighted with fat suppression volume interpolated breath hold examination (VIBE) sequence was acquired before and 5 min,10 min,15 min,20 min after the administration of Gd-EOB-DTPA with both conventional low FA (9 °) and high FA (27 °) protocols separately.Signal to noise ratio (SNR),liver to lesion contrast (LLC),the liver to lesion SI ratio (LLSIR) were calculated and analyzed between low and high FA protocol images in each group and each scan time.Results The LLC and LLSIR on GdEOB-DTPA-enhanced MR images using a high FA (27 °) protocol were significantly higher in comparison with the conventional low FA (9°).In Child B group and Child C group,the LLC and the LLSIR with low FA significantly reduced during 15～20 min after contrast agent injection,however with high FA,the value of LLC and LLSIR tended to be horizontal.Conclusion A high FA protocol in comparison with the conventional 9° FA can obviously improve the image quality,which is reliable for liver lesion depiction on GdEOB-DTPA-enhanced MR images,especially to those with severe liver cirrhosis.

The inflammatory lesion of the pituitary gland is unusual. A 33-year-old woman with headache, visual impairment, and menelipsis was admitted to the Second Xiangya Hospital, Central South University. The results of magnetic resonance imaging (MRI) for pituitary gland showed a sellar mass with iso-intensity on T1 weighted imaging and high signal on T2 weighted imaging. The homogeneous lesion was enhanced on contrast MRI. The pituitary stalk was thickened accompanied by the cavernous sinus invasion, which showed a "triangle" saddle occupation on the MRI coronal plane. An endocrinological examination revealed mild hypocortisolism. Th e patient was diagnosed as pituitary adenoma based on the MRI findings and endocrinological examination. Trans-sphenoidal surgery was performed. The intra-operative histological examination also suggested a pituitary adenoma. Th e histopathological examination showed accumulation of foamy cells and xanthomatous epithelioid cells, supporting the diagnosis of xanthomatous hypophysitis. Xanthomatous hypophysitis possesses certain MRI features. Th e most typical imaging features are the thickening of the pituitary stalk and the sign of "triangle" occupation on MRI coronal plane, which are very helpful to the correct diagnosis and optimal management.
Adenoma ; diagnosis ; Adult ; Female ; Humans ; Magnetic Resonance Imaging ; Pituitary Diseases ; diagnosis ; Pituitary Gland ; pathology ; Pituitary Neoplasms ; diagnosis

OBJECTIVE: To determine the CT imaging features for retroperitoneal solitary fibrous tumor (SFT).
 METHODS: The imaging features of CT for 2 SFT cases, confirmed by pathological examination, were retrospectively analyzed and compared with pathological results.
 RESULTS: The results of CT showed that retroperitoneal SFTs were large, well-defined and consisted of solid components with different density (equal or low). In the scan of contrast enhancement, tumors were strongly enhanced, and the multiple vascular shadows were seen in the tumor at arterial phase. There was progressive enhancement from the arterial to venous phase, and capsule of tumor was displayed. Histologically, the tumors were composed of spindle cells within a background of collagen stroma, and showed a wide range of growth patterns, alternating hypercellular (tumor cell-rich) and hypocellular (collagen-rich) areas. The diagnosis was confirmed by positive immunohistochemical staining for CD34 and bcl-2.
 CONCLUSION The retroperitoneal SFT possesses a definite characteristic in CT imaging features, and the diagnosis can be confirmed by histopathology and immunohistochemistry.
Humans ; Hyperplasia ; Immunohistochemistry ; Retroperitoneal Space ; pathology ; Retrospective Studies ; Solitary Fibrous Tumors ; diagnosis ; Tomography, X-Ray Computed

Susceptibility weighted imaging (SWI) is a magnetic resonance technology with a high resolution, three-dimensional gradient echo and fully velocity compensated sequence. It is also sensitive to substance with different magnetisability. Based on the quantitative reconstruction of SWI, quantitative susceptibility mapping (QSM) has been used in monitoring the change of intravenous iron, calcium, microbleeds and oxygen content. This article summarizes principle of QSM and the latest progress of QSM application in the diseases of central nervous system.
Calcium ; chemistry ; Central Nervous System ; Humans ; Iron ; chemistry ; Magnetic Resonance Imaging ; Oxygen ; chemistry

OBJECTIVE: To explore CT findings and pathologic basis of crazy paving pattern caused by pulmonary alveolar proteinosis. METHODS: Twenty-four patients who were diagnosed pathologically as pulmonary alveolar proteinosis by transbronchial lung biopsy and bronchoalveolar lavage fluid from June 2006 to May 2012 were included in this retrospective study. All patients underwent a 64-slice CT of the lungs. RESULTS: CT findings: crazy paving pattern was observed on CT imaging of all 24 patients. In 23 patients, crazy paving pattern displayed strip-shaped opacities with smooth edges, and there was a clear boundary between the pathological and normal lung tissues. The reticular opacities were connected with peripheral blood vessels and the branches were formed, and their diameters decreased slightly. Microscopically, hemangiectasis were seen in 17 patients. CONCLUSION Crazy paving pattern caused by pulmonary alveolar proteinosis displayed clear edges, and smooth reticular opacities, most of which were due to hemangiectasis of interlobular, interacinar and interalveolar septa. These findings of CT are helpful for the specific diagnosis of pulmonary alveolar proteinosis.
Biopsy ; Humans ; Lung ; pathology ; Pulmonary Alveolar Proteinosis ; pathology ; Retrospective Studies ; Tomography, X-Ray Computed

Objective To investigate the application of PBL and LBL teaching in medical imag-ing teach-ing. Methods Totally 124 five-year clinical students were divided into two groups:PBL teaching (n=57)and LBL teaching(n=67). Teaching in PBL group was conducted through the following 6 proce-dures:grouping-giving cases-asking questions-establishing hypothesis-collecting data-hypoth-esis testing-team summarizing. Teaching in LBL group was conducted mainly by teachers with multime-dia, course-ware,wall charts,models,samples,etc and finally summarized by teachers. Effect was eval-uated by reading test,closed-book exam and questionnaire survey. t test was employed to do statically analysis,with P≤0.05 being statistical differences. Results Reading test score ((82.4±14.8)vs (74.5±9.7))and case analysis score((13.9±5.1)vs (10.2±6.1))were higher in PBL group than in LBL group(P≤0.05). Most students in PBL group appreciated the teaching method. Conclusions PBL teaching can help improve the clinical analysis of students and is welcomed by students. Moreover, PBL,as a supplement of traditional teaching,can initiate the learning interests and enhance the innova-tion of students.

Objective:To explore whether the phospholipidoproteinaceous material deposit within the alveoli by a high-ifeld 3T MRI has signal characters and its application for diagnosing pulmonary alveolar proteinosis.Methods:A total of 11 patients with pulmonary alveolar proteinosis previously diagnosed by ifberoptic bronchoscope lung biopsy underwent 64-slice helical CT scans and 3T MRI scans, and the CT scans and the MRI scans were compared.
Results:hTe phospholipidoproteinaceous material deposit within the alveoli presented longer or equal T1 relaxation time and longer T2 relaxation time, without characters of fatty or deposits of protein-like substance signals and enhancement. The distribution, form, number and size of the lesions at T2WI were almost the same as those at CT, the lesions were irregular in morphology, and there was a clear boundary between the lesions and the adjacent normal lung tissues. Dynamic contrast-enhanced MRI showed thickened pulmonary arteriolae and venulae in the lesions with more obviously thickened pulmonary venulae, which were in conformity with the pulmonary artery and venule enhancement. CT scan in 1 out of the 11 cases showed lesions in both lungs mainly consisted of stripe-shaped and reticular structures, and no obvious sign of pulmonary alveolar proteinosis residue was found. MRI scan detected alveolar proteinosis that failed to be shown by CT scan.
Conclusion:3T MRI T2WI can easily detect the lesions of long T2 signals formed by the lipoproteinaceous material deposit within the alveoli. In the lesions, geographic appearance was presented, and the crazy paving pattern was dimly visualized. MRI can relfect the morphological characters of PAP like CT and it is slightly better compared with CT in such aspects as evaluating the theraputic effect of lung lavage. As supplement to CT, high-field 3T MRI can serve as an important examination for lung diseases.

OBJECTIVE: To diagnoze active ankylosing spondylitis (AAS) by magnetic resonance imaging (MRI). METHODS: MRI of the sacroiliac joint (SIJ) was performed on 48 patients who were clinically diagnosed as probable AS without radiologic evidence of sacroiliitis. Among them 21 were diagnozed as active sacroiliitis with MRI, whose examination was terminated; 27 whose MRI of SIJ did not diagnoze as active sacroiliitis were performed MRI in the thoracic spine. The diagnostic criteria of MRI for AAS of SIJ and/or the thoracic spine were fomulated by consulting documents. The definite diagnosis of AAS was finally made after follow-up for half a year. The sensitivity and specificity of the MRI of SIJ and/or MRI of thoracic spine were assessed. RESULTS: In the 48 patients without radiologic evidence of sacroiliitis, 38 were finally diagnosed as AAS, with established consensus criteria as reference standard. The sensitivity and specificity of the MRI of SIJ were 52.6% and 90.0%, and for the MRI of SIJ and/or the MRI of the thoracic spine 76.3% and 90.0%, respectively. CONCLUSION Clinically probable AS without MRI evidence of sacroiliitis, MRI of the thoracic spine can increase the sensitivity of AAS diagnosis.
Adolescent ; Adult ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Radiography ; Sacroiliac Joint ; diagnostic imaging ; pathology ; Spondylitis, Ankylosing ; diagnosis ; Thoracic Vertebrae ; pathology ; Young Adult

OBJECTIVE: To explore characteristic CT findings and pathologic basis of ground glass opacity caused by pulmonary alveolar proteinosis (PAP). METHODS: Retrospective analysis of CT and pathological findings of 24 patients with PAP who were pathologically diagnosed from June 2006 to August 2011. RESULTS: Findings with CT: the lesions of the 24 patients mainly presented ground glass opacities. Local consolidations were seen in 8 patients. In 23 patients part of ground glass opacities bordered strip-shaped opacities with smooth edges, and there was a clear boundary between them and the bordering normal lung tissues, presenting a geographic appearance. Lesions in the 5 cases were mixed with alveoli or lobule aerocele, which made ground glass opacities present curved edges. Crazy paving pattern was detected in the 24 patients. Microscopically, the alveoli were seen to be filled with floccules proteinaceous material in various quantities in the 24 patients; hemangiectasis and congestion were seen in 17 patients, and enlarged alveolar cavities were seen in 5 patients. CONCLUSION PAP usually causes ground glass opacities with clear edges, and different from ground glass opacities with obscure edges caused by other pulmonary diseases. They are relatively specific to the imagining diagnosis to PAP.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Pulmonary Alveolar Proteinosis ; diagnostic imaging ; pathology ; Retrospective Studies ; Tomography, X-Ray Computed

OBJECTIVE: To analyze the multislice spiral computer tomography (MSCT) manifestations and its value in the diagnosis of urachus lesions. METHODS: A total of 26 patients with urachus disease diagnosed by pathological examination in our hospital between October 2007 and May 2011 were included in this study. We retrospectively analyzed MSCT images on the size, location, and shape character of the foci, and the image features of Retzius space. RESULTS: In the group, 12 patients had simple urachal cyst with homogeneous fluid filling the cavity with thin wall in CT scanning; five had infected urachal cyst with thickened and enhanced wall, some patch and strip appearing in Retzius space surrounding the lesion; two had infected urachal sinus, and another 3 had urachus leakage. Four had urachal tumor showing irregular cysticsolid mass over the apex of the bladder with apparent enhancement in contrast imaging, and 2 had calcification. Invasion of the bladder wall was found in 4 patients, extensive invasion of the ileum, rectum, uterus and retroperitoneal lymph nodes was found in 1. CONCLUSION MSCT scan can demonstrate the location, shape, extent of the lesion as well as the relation with adjacent structures, thereby providing valuable information for the diagnosis and differential diagnosis of urachus lesions.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Infections ; complications ; Male ; Middle Aged ; Multidetector Computed Tomography ; Urachal Cyst ; complications ; diagnostic imaging ; Urachus ; diagnostic imaging ; pathology ; Young Adult