[en] Objective: To evaluate the HRCT in Diagnosis of endo-bronchial tuberculosis (EBTB). Methods: In total 103 cases of EBTB were examined with chest radiography, tomography and CT scan. Results: More direct signs including narrowed bronchi, thickened bronchial wall, intra-luminal nodules and bronchial obstruction, were demonstrated on CT or HRCT than those revealed on chest radiography and tomography, HRCT was superior to chest radiography or tomography in showing tiny shadows and involved bronchial tree. Conclusion: CT, particularly HRCT is superior to chest radiography, tomography in the diagnosis of EBTB

[en] Objective: To investigate the etiology of non-diving bone infarct of lower extremities in the senile patients and the imaging findings. Methods: In total 17 patients with lower extremity pain received routine radiography in the frontal and lateral projection. Additionally, CT scan was performed in 3 patients and MRI in 2. Results: Lesions were located bilaterally in 6 cases, unilaterally in 11 cases. Totally 36 sites were revealed: in a descending sequence of the frequency of involvement there were lower femur (16 lesions), proximal tibia (13 lesions) and lower tibia (5 lesions), and calcaneus (2 lesions). Typical imaging manifestations were revealed. Laboratory tests showed high concentration of total cholesterol and TG in serum. Conclusion: The etiology of the non-diving bone infarct in the senile patients remains unclear. Radiography and MRI are the choices of imaging, which will reveal the extension of the lesion and confirm the diagnosis. (authors)

[en] Objective: To compare the Chinese 2008, 1992 and 2002 UICC (International Union Against Cancer) staging System for nasopharyngeal carcinoma and find out the reasons for the changes in the new Chinese 2008 staging system. Methods: From Apr. 2007 to Dec. 2008, 285 naive patients with pathologically proved NPC, but without metastasis, received standard enhanced MRI scans of the nasopharynx and neck. Based on MRI imaging data and clinical information, clinical stage was classified according to the Chinese 2008, Chinese 1992 staging system and 2002 6^th UICC staging system, respectively. Comparisons were made between Chinese 2008 and 1992 staging system, and between Chinese 2008 and 2002 UICC staging system by χ² test. Results: As a result of deleting some details of the old staging system, Chinese 2008 staging system is easier to grasp. With Chinese 2008 staging system, the number of cases in stage T₁ to T₄ are 66, 84, 72, 63, respectively; those in stage N₀ to N₃ are 12, 48, 169, 56; the number of cases in clinical stage Ⅰ-Ⅳ are 5, 30, 141 and 109. With 2002 6^th UICC staging system, the number of cases in stage T₁ to T₄ are 66, 83, 55, 81; those in stage N₀ to N₃ are 26, 50, 201, 8; the number of cases in clinical stage Ⅰ-Ⅳ are 6, 40, 153 and 86. With Chinese 1992 staging system, the number of cases in stage T₁ to T₄ are 62, 91, 71, 61; those in stage N₀ to N₃ are 26, 189, 61, 9; the number of cases m clinical stage Ⅰ-Ⅳ are 6, 110, 98 and 71. Comparing with the staging results of Chinese 1992 staging system, many cases showed different stage based on Chinese 2008 system including 12 cases (4.21%) in T stage (3 up-staging and 9 down-staging), 217 cases (76.14%) in N stage (216 up- staging, most rise 1 stage, and 1 down-staging), 123 cases (43.16%) in clinical stage (121 up-staging and 2 down-staging). Comparing with the staging results of 2002 UICC staging system, 35 cases (12.28%) changes in T stage (8 up-staging and 27 down-staging), 77 cases (27.02%) changes in N stage (all up- staging, most rise 1 stage), 74 cases (25.95%) changes in clinical stage (54 up-staging and 20 down- staging)based on Chinese 2008. Comparing the constituent ratio of T, N and clinical staging results separately, statistical differences were found between Chinese 2008 and Chinese 1992 staging system in No , N₁, N₂, N₃, clinical stage Ⅱ, Ⅲ, Ⅳ. Statistical difference was also found in N₀, N₂, N₃, clinical stage Ⅳ between Chinese 2008 and 2002 UICC staging system. χ² test results show that there is N₀ significant difference of T stage constituent ratio among the 3 staging system (χ²=6.916, P=0.329), but the difference of N stage and clinical stage constituent ratio are significant (χ²=275.169 and 84.515, P< 0.0125). Conclusion: Chinese 2008 Staging System for nasopharyngeal carcinoma is based on MRI, with clear definition to some anatomical location, after deleting some details in the old stage system, it's easier to use. The most obvious change for Chinese 2008 Staging System is the up-staging in N staging, which leads to the changes in clinical stage and constituent ratio of stage result. (authors)

[en] Objective: To investigate the value of diffusion weighted imaging (DWI)on brain abscess and necrotic or cystic brain tumors. Methods: 27 cases with brain abscesses and 33 cases with necrotic or cystic brain tumors (gliomas or metastases) were performed conventional MRI and DWI. Apparent diffusion coefficient (ADC) of region of interest (ROI) was measured and statistically tested. Sensitivity and specificity were calculated and compared with conventional MR and DWI. Results: Hyperintensity signal was seen on most brain abscesses. All necrotic or cystic brain tumors showed hypointensity signal on DWI. There was statistical significance on ADC of them. The sensitivity and specificity of conventional MRI was lower than that of DWI. Conclusion: DWI and ADC were useful in distinguishing brain abscessed from necrotic or cystic brain tumors, which was important in addition to conventional MRI. (authors)

[en] Objective: Preliminarily analysis of the MRI features of bladder leiomyoma. Methods: The MRI manifestations were analyzed with review of previous released literatures in a case of bladder leiomyoma, which was confirmed by pathology. Results: The lesion manifested homogeneous intermediate signal intensity both on non-enhanced T₁WI and T₂WI, and intermediate enhancement on contrast enhanced T₁WI. There was no pedicle on the tumor and the tumor-bladder junction had an acute angle, indicating its benign nature. Conclusion: Non-epithelial tumor has characteristic signals in non-enhanced MRI, in which the leiomyoma of bladder is the most frequent benign neoplasm encountered. Considering enhanced MRI findings, the morphology and growth pattern of the tumor, accurate diagnosis can be made in some cases of bladder leiomyoma, providing valuable informations for surgical planning. (authors)

[en] How to monitor and track the survival, migration and differentiation of grafted stem cell in vivo is necessary for the widespread clinically application of stem cell transplantation. Manegtic resonance imaging (MRI), which can display and specifically track and localize labelled stem cell by paramagnetically labelling of the stem cell, is an extremely prospective method to monitor stem cell in vivo. The ferrum and gadolinium derivative contrast agents were mainly used to paramagnetically label the stem cell, and each had its own advantages and disadvantages. Currently, on the basis of paramagnetically labelling of the stem cell with ferrum and gadolinium derivative contrast agents, MRI had been successfully used to monitor the stem cell in vivo and had been applied into animal model of the heart and brain stroke, but these are still some problems exist such as the selection of vehicle transferring the contrast agents into stem cells, the labeling efficiency, the duration of labelling and the viability and heredity changes of the stem cell after labelling. (authors)

[en] Objective: To study the effects of the strength and number of b values on ADC measurements of normal brain. Methods: Seven different diffusion weightings were applied in twenty normal adult brains in diffusion tensor imaging. the brain ADC maps were calculated using seven different combinations of b values based on strength (b₀b₁, b₀b₂, b₀b₃, b₀b₄, b₀b₅) and on numbers (b₀b₆. b₀b₆, b₀b₁b₆, b₀b₁b₂b₆, b₀b₁b₂b₃b₆, b₀b₁b₂b₃b₄b₆ and b₀b₁b₂b₃b₄b₅b₆). The average of the ADC was measured and compared at the caudate nucleus, posterior limb of the internal capsule, thalamus, centrum semiovale, genu of corpus callosum and splenium of corpus callosum. Results: The measured ADC was significantly decreased accompanied with increase of b values (P<0.05), but did not correlated with the b values number (P>0.05). Conclusion: The strength of b values, not numbers of b value influences measurement of ADC, which should be considered in clinical study

[en] Objective: To analyze the CT and MRI manifestations of nasopharyneal angiofibroma. Methods: 21 cases of nasopharyneal angiofibroma are retrospectively analyzed according to the location, size, margin, density or signal of the tumor and the changes of surrounding bones. Results: The CT and MRI showed a nasopharyneal mass with well-defined margin, uniform density or signal and remarkably enhanced. The sphenomaxillary fossa was enlarged and the posterior wall of maxillary sinus was, compressed and displaced without bone destruction. The surrounding bone appeared to be compressed, molded, absorbed or destroyed. Conclusion: CT examination can usually provide diagnostic information, but the combination of CT and MRI can be better contributed to the diagnosis, location and stage classification of nasopharyneal angiofbroma. (authors)

[en] Objective: To evaluate CT and MRI findings of the adrenal cyst in order to improve diagnostic accuracy. Methods: The CT or MRI studies of 10 histologically-proven adrenal cysts were retrospectively analyzed. Results: CT was performed in 6 cases and showed smooth thin cyst wall (6), mural calcification (1), septation with punctuate calcification (1). The CT densities of cyst fluid were 15-30 Hounsfield units without contrast enhancement. The wall of 1 cyst enhanced slightly whereas the remaining 5 did not enhance with intravenous contrast. All 4 cysts on MRI were T₁ hypointense and T₂ hyperintense without contrast enhancement. Conclusion: CT and MRI findings of adrenal cysts are characteristic and conducive to diagnosis. (authors)

[en] Objective: To explore the distribution and features of cervical nodes metastasis from nasopharyngeal carcinoma (NPC). Methods: The MR imagings of 315 patients with newly diagnosed NPC were reviewed retrospectively. Nasopharyngeal MRI scan was performed in all patients. Conventional plain MRI sequences including axial, coronal and sagittal T₁ weighted-imaging and axial T₂ weighted-imaging were done. Conventional: T₁ contrast enhanced imaging was obtained after bolus injection of Gd-DTPA. Results: Of 315 patients, 254 (80.6%) had cervical lymphadenopathy. Of the 254 neck positive cases, 233 cases showed enlargement of retropharyngeal nodes (RN), which were most commonly involved. A higher incidence in metastatic cervical nodes was seen in patients with primary tumor located on bilateral than on unilateral nasopharynx (χ²=5.125, P<0.05). Central necrosis and extracapsular spread and fusion were easier to be seen in metastatic cervical nodes than in nasopharynx. Conclusion: NPC has a high incidence of cervical lymph node metastases. Nodes in RN are most commonly involved. There are more metastatic cervical nodes in patients with primary tumor located on bilateral than on unilateral nasopharynx. The incidence of central nodal necrosis and extracapsular nodal spread and fusion was very high. (authors)