[Radiological progression and life quality analysis in ankylosing spondylitis patients using etanercept/methotrexate combination therapy].

OBJECTIVE: To analyze the relationship between the radiological progression and quality of life in ankylosing spondylitis (AS) patients using etanercept/methotrexate (MTX) combination therapy. METHODS: A total of 153 AS cases fulfilling the 1984 modified New York diagnostic criteria were reviewed. All patients received radiological evolution at baseline and during a follow-up period. Radiological progression, clinical remission and life quality were recorded and analyzed for their relations. RESULTS: The radiological assessments of mSASSS (modified Stoke ankylosing spondylitis spine score) were recorded at baseline, 3, 6 & 12 months after treatment. Life quality assessments were recorded with SF (short-form)-36 simultaneously. No significant radiological improvement was observed at the end points. However, most patients reported a significant improvement of life quality after a combination therapy of etanercept/MTX. BASDAI (Bath ankylosing spondylitis disease activity index), C-reactive protein and erythrocyte sedimentation rate demonstrated similar trends. With no relevance with mSASSS, life quality was significantly correlated with disease activity and pain control. CONCLUSION: The combination therapy of etanercept/MTX greatly improves life quality in AS patients. Yet clinical remission and pain control offer no hint of a suspension of radiological progression. Routine radiological assessment is required throughout the follow-up period of AS even if life quality index reaches a high level.

Comparative study on imaging and pathological features of elastofibroma dorsi.

BACKGROUND AND OBJECTIVE: Elastofibroma dorsi has an extremely low incidence. At present, comparative study on imaging manifestations and pathologic findings of elastofibroma dorsi has not been reported in China. This study was to investigate clinical manifestations, computed tomography (CT) and magnetic resonance imaging (MRI) appearances, and pathologic features of elastofibroma dorsi and to improve preoperative imaging diagnosis of this disease. METHODS: The clinical manifestations, imaging findings, and pathologic appearances of 6 cases of elastofibroma dorsi were retrospectively analyzed and related literatures were reviewed. All patients were examined with MRI, and 4 of them were examined with CT scan. RESULTS: All patients were above 30 years old without obvious symptoms. The tumors presented as a lenticular soft-tissue mass in the deep subscapular region. The tumor's density on plain CT scan or signal intensity on MR T1-weighted image was approximately equal to that of muscle with some interlaced fat-like areas within mass suppressed by fat-suppression MR sequences, which corresponded to dense collagen tissue and interspersed mature adipose tissue observed microscopically. CONCLUSIONS: CT and MRI can reflect the histological features of elastofibroma dorsi. On the basis of their imaging characteristics, a correct preoperative diagnosis of elastofibroma dorsi can easily be made.

Assessment of spiral CT pneumocolon in preoperative colorectal carcinoma.

AIM: To investigate the value of spiral CT pneumocolon in preoperative colorectal carcinoma. METHODS: Spiral CT pneumocolon was performed prior to surgery in 64 patients with colorectal carcinoma. Spiral CT images were compared to specimens from the resected tumor. RESULTS: Spiral CT depicted the tumor in all patients. Comparison of spiral CT and histologic results showed that the sensitivity and specificity were 95.2%, 40.9% in detection of local invasion, and 75.0%, 90.9% in detection of lymph node metastasis. Compared to the Dukes classification, the disease was correctly staged as A in 6 of 18 patients, as B in 18 of 23, as C in 10 of 15, and as D in 7 of 8. Overall, spiral CT correctly staged 64.1% of patients. CONCLUSION: Spiral CT pneumocolon may be useful in the preoperative assessment of patients with colorectal carcinoma as a means for assisting surgical planning.

Tumor angiogenesis and dynamic CT in colorectal carcinoma: radiologic-pathologic correlation.

AIM: To investigate the correlation between microvessel density and spiral CT perfusion imaging in colorectal carcinoma. METHODS: Thirty-seven patients, with histologically proven colorectal carcinoma, underwent water enema spiral CT scan. The largest axial surface of the primary tumor was searched on unenhanced spiral CT images. At this level, the enhanced dynamic scan series was acquired. Time-density curves (TDC) were created from the region of interest drawn over the tumor, target artery by Toshiba Xpress/SX spiral CT with perfusion functional software. Then the perfusion was calculated. Microvessel density (MVD) was evaluated using immunohistochemical staining of surgical specimens with anti-CD34, and then MVD was correlated with perfusion. RESULTS: MVD of colorectal carcinomas was 33.11-173.44, mean 87.28, and perfusion was 15.60-64.80 mL/min/100 g, mean 39.74 mL/min/100 g. MVD and perfusion were not associated with invasive depth, metastasis and disease stage, and they all decreased with increasing Dukes' stage, but no significant correlation was found between them (r = 0.18, P = 0.29). CONCLUSION: There is no significant correlation between MVD and perfusion. Neovascularizaton and perfusion are highly presented in early colorectal carcinoma. CT perfusion imaging may be more suited for assessing tumorigenesis in colorectal carcinoma than histological MVD technique.

Preoperative easily misdiagnosed telangiectatic osteosarcoma: clinical-radiologic-pathologic correlations.

PURPOSE: To describe the clinical, imaging, and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma (TOS) for improving the diagnostic level. MATERIALS AND METHODS: The authors retrospectively reviewed patient demographics, serum alkaline phosphatase (AKP) levels, preoperative biopsy pathologic reports, pathologic materials, imaging findings, and treatment outcomes from 26 patients with TOS. Patient images from radiography (26 cases) and magnetic resonance (MR) imaging (22 cases) were evaluated by 3 authors in consensus for intrinsic characteristics. There were 15 male and 11 female patients in the study, with an age of 9-32 years (mean age 15.9 years). RESULTS: Eighteen of 26 patients died of lung metastases within 5 years of follow-up. The distal femur was affected more commonly (14 cases, 53.8%). Regarding serum AKP, normal (8 cases) or mildly elevated (18 cases) levels were found before preoperative chemotherapy. Radiographs showed geographic bone lysis without sclerotic margin (26 cases), cortical destruction (26 cases), periosteal new bone formation (24 cases), soft-tissue mass (23 cases), and matrix mineralization (4 cases). The aggressive radiographic features of TOS simulated the appearance of conventional high-grade intramedullary osteosarcoma, though different from aneurysmal bone cyst. MR images demonstrated multiple big (16 cases) or small (6 cases) cystic spaces, fluid-fluid levels (14 cases), soft-tissue mass (22 cases), and thick peripheral and septal enhancement (22 cases). Nine of 26 cases were misdiagnosed as aneurysmal bone cysts by preoperative core-needle biopsy, owing to the absence of viable high-grade sarcomatous cells in the small tissue samples. CONCLUSION: The aggressive growth pattern with occasional matrix mineralization, and multiple big or small fluid-filled cavities with thick peripheral, septal, and nodular tissue surrounding the fluid-filled cavities are characteristic imaging features of TOS, and these features are helpful in making the correct preoperative diagnosis of TOS.

[Assessment of 64-slice spiral computed tomography angiography with image fusion for perigastric arteries anatomy].

OBJECTIVE: To evaluate the efficacy and clinical significance of 64-multislice spiral computed tomography angiography(MSCTA) with image fusion for the anatomy of perigastric arteries. METHODS: A total of 53 patients underwent abdominal 64-MSCTA, among whom 26 patients with gastric cancer underwent gastrectomy. Using volume rendering techniques, computed tomography angiography(CTA) of perigastric arteries and the stomach were reconstructed respectively, and then the images were fused together. The branching pattern of the celiac trunk and the origins and courses along the stomach of the 10 perigastric arteries were assessed. The accuracy, sensitivity, and specificity of 64-MSCTA were determined based on intraoperative findings. RESULTS: CTA clearly showed the celiac trunk. The most common branching pattern of the celiac trunk was Michels type I( in 46 patients(86.8%). The anatomy of perigastric arteries and stomach could be clearly demonstrated from any angle according to image fusion. The left gastric artery and the right gastroepiploic artery were shown in 100%, the left gastroepiploic artery 94.3%(50/53), the right gastric artery 83.0%(44/53), short gastric artery 58.5%(31/53), posterior gastric artery 49.1%(26/53), the replaced left hepatic artery 15.1%(8/53). The accessory left hepatic artery, accessory left gastric artery and replaced right hepatic artery were all identified in 7.5%(4/53) patients. The accuracy of preoperative CTA in term of correctly identifying perigastric arteries ranged from 84.6% to 100%, the sensitivity 82.6% to 100%, and the specificity was 100% for all the perigastric arteries. CONCLUSIONS: 64-MSCTA can clearly reveal individual perigastric arteries. The anatomy of the stomach and perigastric arteries can be shown in vivo by fused image, and can provide guidance for gastrectomy.

[Pilot study on MRI of human colon adenocarcinoma cells labeled with superparamagnetic iron oxide in vitro].

OBJECTIVE: To study the feasibility of MRI of human colon adenocarcinoma cell line (Lovo) labeled with superparamagnetic iron oxide(SPIO) nanoparticles in vitro. METHODS: Lovo cells (5 × 10(5) and 1 × 10(6)) were cultured in medium containing different SPIO nanoparticles (50 microl and 500 microl). Transmission electron microscopy was used to observe cellular ultrastructure and to determine the uptake and distribution of particles in Lovo cells at 1-, 3-, 6-hours. MRI of Lovo cells was performed with T1WI, T2WI sequences. Unlabeled cells were used as controls. RESULTS: Uptake of SPIO nanoparticles occurred within 6 hours. On T1 weighted imaging, there was no significant difference in signal intensity between the experimental groups and the control group. On T2 weighted imaging, there was no significant difference in signal intensity between the experimental groups and the control group after culture of 1 h. Signal intensity began to decrease in 1 × 10(6) Lovo cells labeled with 500 microl SPIO nanoparticle after 3 hours culture. Signal intensity decreased in all the experimental groups after 6 hours culture. CONCLUSION: Human colon adenocarcinoma cell line (Lovo) can be labeled with SPIO nanoparticles, and the labeled cells can be imaged with MRI equipment.

Quantitative assessment of perirectal tumor infiltration with dynamic contrast-enhanced multi-detector row CT in rectal cancer.

OBJECTIVE: To evaluate the efficacy of discriminant function analysis of perirectal tumor infiltration with dynamic contrast-enhanced 64-detector row CT in rectal cancer. MATERIALS AND METHODS: Forty-nine patients with rectal cancer underwent dynamic contrast-enhanced CT. A total of 96 axial CT slices containing the tumors were evaluated. The 96 images were separated into two groups with or without perirectal tumor infiltration based on pathological findings. The discriminant function was set-up using CT density differences between the mass and the adjacent perirectal tissue within 5 mm from the mass at 20 and 40 s as independent variables. The results of the discriminant function analysis were compared to those of CT morphology and pathology. RESULTS: CT morphological diagnosis was accurate on 71.9% (69/96) of the slices with 82.5% sensitivity and 64.3% specificity. Discriminant function analysis correctly identified 88.5% (85/96) of the slices with 85.0% sensitivity and 91.1% specificity. Overstaging occurred significantly more (P<0.05) on morphological analysis (20.8%, 20/96) than discriminant function analysis (5.2%, 5/96) of the CT slices. CONCLUSIONS: Discriminant function analysis of dynamic contrast-enhanced CT improves the diagnostic accuracy and specificity of perirectal tumor infiltration in rectal cancer.

[Application of 64MDCT multislice perfusion imaging in colorectal carcinoma].

OBJECTIVE: To study the correlation of time-density curves (TDC), parameters revealed by 64-multidetector-row CT (64MDCT) perfusion imaging with clinicopathological factors (staging, serosal invasion, lymph node metastasis, distant metastasis and CEA) in colorectal carcinoma (CRC). METHODS: 64 MDCT perfusion imaging was performed in 33 patients with pathologically verified CRC. TDC was created from the region of interest (ROI) drawn over the tumor, target artery and vein by 64MDCT with perfusion functional software. The parameters of individual perfusion maps included blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability-surface area product (PS). Tumors were staged according to TMN classification. TDC was classified according to their shapes. The correlation between CT perfusion parameters and clinicopathological factors was studied. RESULTS: TDC of 64MDCT perfusion imaging could be classified into five types. TDC in different stages could demonstrate one or more types of the five types. There was no significant difference of CT perfusion parameters among different stages. BV and MTT were significantly higher in the patients with serosal invasion than in those without serosal invasion (t=-2.63,-2.24, P=0.0137, 0.0331, respectively). BV was significantly correlated with tumor size (r=0.41, P=0.02). BF and PS were not correlated with staging, serosal invasion, lymph node metastasis, distant place metastasis and CEA (all P>0.05). CONCLUSIONS: 64MDCT multislice perfusion imaging can reveal the blood perfusion of CRC and has potential value of clinical application.

Radiation dose and cancer risk from pediatric CT examinations on 64-slice CT: a phantom study.

OBJECTIVE: To measure the radiation dose from CT scans in an anthropomorphic phantom using a 64-slice MDCT, and to estimate the associated cancer risk. MATERIALS AND METHODS: Organ doses were measured with a 5-year-old phantom and thermoluminescent dosimeters. Four protocols; head CT, thorax CT, abdomen CT and pelvis CT were studied. Cancer risks, in the form of lifetime attributable risk (LAR) of cancer incidence, were estimated by linear extrapolation using the organ radiation doses and the LAR data. RESULTS: The effective doses for head, thorax, abdomen and pelvis CT, were 0.7mSv, 3.5mSv, 3.0mSv, 1.3mSv respectively. The organs with the highest dose were; for head CT, salivary gland (22.33mGy); for thorax CT, breast (7.89mGy); for abdomen CT, colon (6.62mGy); for pelvis CT, bladder (4.28mGy). The corresponding LARs for boys and girls were 0.015-0.053% and 0.034-0.155% respectively. The organs with highest LARs were; for head CT, thyroid gland (0.003% for boys, 0.015% for girls); for thorax CT, lung for boys (0.014%) and breast for girls (0.069%); for abdomen CT, colon for boys (0.017%) and lung for girls (0.016%); for pelvis CT, bladder for both boys and girls (0.008%). CONCLUSION: The effective doses from these common pediatric CT examinations ranged from 0.7mSv to 3.5mSv and the associated lifetime cancer risks were found to be up to 0.16%, with some organs of higher radiosensitivity including breast, thyroid gland, colon and lungs.

Multiphasic MDCT in small bowel volvulus.

OBJECTIVE: Evaluate the use of MDCT with 3D CT angiography (CTA) and CT portal venography (CTPV) reconstruction for the diagnosis of small bowel volvulus (SBV). METHODS: Multiphasic MDCT findings in nine patients (seven males and two females, age range 2-70) with surgically proven SBV were retrospectively reviewed. Non-contrast and double phase contrast enhanced MDCT including 3D CTA and CTPV reconstruction were performed in all the patients. Two experienced abdominal radiologists evaluated the images and defined the location, direction and degree of SBV. RESULTS: On axial MDCT images, all cases show segmental or global dilatation of small intestine. Other findings include circumferential bowel wall thickening in eight cases, halo appearance and hyperemia in seven cases, whirl sign in six cases, beak-like appearance in six cases, closed loops in six cases and ascites in one case. CTA/CTPV showed abnormal courses involving main trunks of superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in seven cases, with or without distortion of their tributaries. Normal course of SMA but abnormal course of SMV was seen in the other two cases. Of all the nine cases, whirl sign was seen in six cases and barber's pole sign in five cases. Dilated SMV was observed in eight cases and abrupt termination of SMA was found in one case. Compared with surgical findings, the location, direction and degree of SBV were correctly estimated in all cases based on CTA/CTPV. CONCLUSION: Multiphasic MDCT with CTA/CTPV reconstruction can play an important role in the diagnosis of SBV. The location, direction and degree of SBV can all be defined preoperatively using this method.

CT and MR imaging characteristics of infantile hepatic hemangioendothelioma.

AIM: This study aims to analyze computed tomography (CT) and magnetic resonance (MR) imaging features of infantile hepatic hemangioendotheliomas before and after treatment. MATERIALS AND METHODS: CT and MR examinations of seven infants with biopsy proven hepatic hemangioendotheliomas were retrospectively analyzed. The distribution, number, size, imaging appearance, enhancement pattern and post-treatment changes of the tumors were evaluated. RESULTS: A total of 153 hepatic hemangioendotheliomas were detected on CT (111) and MR (42) imaging. In six infants, 109/111 (98.2%) tumors were hypodense and 2/111 (1.8%) lesions contained calcification on unenhanced CT. On MR imaging, all 42 lesions in one infant were heterogeneously T1-hypointense and T2-hyperintense compared to the normal liver parenchyma. Contrast-enhanced CT and MRI showed peripheral rim (51.6%), uniform (48.4%), fibrillary (33.3%), and nodular (28.8%) contrast enhancement in the hepatic arterial phase. Homogeneous (100%), rim (98.2%) and mixed enhancement patterns were noted in tumors <1.0cm, >2.0cm and 1.0-2.0cm in diameter respectively in the hepatic arterial phase. In three patients who underwent steroid therapy, follow-up CT examination demonstrated tumor size reduction and increased intra-tumoral calcification in two patients. CONCLUSION: Infantile hepatic hemangioendotheliomas show some typical imaging features and size-dependent pattern of contrast enhancement on CT and MR imaging, which allow accurate imaging diagnosis and post-treatment evaluation.

Evaluation of angiogenesis in colorectal carcinoma with multidetector-row CT multislice perfusion imaging.

To evaluate the correlation between 64 multidetector-row CT (64MDCT) perfusion imaging in colorectal carcinoma and microvessel density (MVD) and vascular endothelial growth factor (VEGF), 64MDCT perfusion imaging was performed in 33 patients with pathologically verified colorectal carcinoma. These images were analyzed with perfusion functional software, and time-density curves (TDC) were created for the region of interest (ROI) encompassing the tumor, the target artery and vein. The individual perfusion maps generated indicated blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS). MVD and VEGF were evaluated by immunohistochemical staining with anti-CD34 and anti-VEGF, respectively. Correlations between MVD or VEGF with CT perfusion parameters and clinicopathological factors (Dukes' stages, invasion depth, and lymph node and liver metastasis) were also investigated. MVD in the colorectal carcinoma was 22.61+/-9.01 per x200 field. The scores obtained for VEGF expression were 4.15+/-1.09. VEGF staining was positive in 25 of 29 tumors (86.2%). There was no significant correlation between the presence of MVD, VEGF expression and clinicopathological factors (P>0.05). There was also no correlation between MVD, VEGF expression, and any dynamic CT parameters (P>0.05). The BV and MTT were significantly higher in tumors demonstrating serous coat invasion than in those without it (t=-2.63, -2.24, P=0.0137, 0.0331, respectively). BV was also significantly correlated with tumor size (r=0.41, P=0.02). Neither BF nor PS was correlated with clinicopathological factors. In conclusion, 64MDCT perfusion imaging, MVD, and VEGF may reflect angiogenic activity, but no significant correlation among these factors.

[CT and MRI manifestations of pediatric presacral tumors].

BACKGROUND AND OBJECTIVE: The imaging of presacral tumors in children is characteristic. Computed tomography (CT) and magnetic resonance imaging (MRI) have great values in identifying the position, contents and invasion of pediatric presacral tumors before operation. This study was to investigate the CT and MRI features of pediatric presacral tumors, and evaluate the diagnostic values of CT and MRI. METHODS: The CT and MRI data of 24 pediatric presacral tumors were analyzed together with pathologic results. RESULTS: Six cases of pediatric presacral tumors were cystic type, with clear margin and complete capsule, and were composed of multi-capsular spaces; on enhanced scan, the capsular wall showed enhancement, while the cystic contents didn't; all these six cases were confirmed benign by pathology. Five cases were solid type and were enhanced inhomogeneously; all were confirmed malignant by pathology. Thirteen cases were cystic-solid type or with obvious necrosis in solid mass. Of the 13 cases, seven were cystic-solid teratoma (including four benign teratomas and three malignant teratomas confirmed by pathology), containing strip calcification, soft tissue and fat; five were endodermal sinus tumors, showing alveolate enhancement; one was neuroblastoma, with macro-lamellar necrosis, extension to the canalis vertebralis and sacrum invasion. Five tumors, including three teratomas, one rhabdomyosarcoma and one endodermal sinus tumor, had unclear margin. Sacrum invasion was found in one teratoma, one rhabdomyosarcoma, one neuroblastoma and one lymphangioma. CONCLUSIONS: The location and extend of pediatric presacral tumors can by clearly pictured on CT and MRI. Most tumors can be correctly diagnosed according to their imaging features.

Clinical imaging characteristics of herniation pits of the femoral neck.

OBJECTIVE: To discuss imaging features of radiographs, computed tomography (CT), magnetic resonance imaging (MRI) and radionuclide imaging of the herniation pit of the femoral neck and their implications for pathogenesis. METHODS: Twenty-seven patients with 31 herniation pits of the femoral neck were analyzed. All patients were examined by plain radiographs, 18 by CT, 16 by MRI, and 8 by radionuclide imaging. RESULTS: Thirty-one herniation pits located in the anterior part of the femoral neck or the base of the femoral head were round, oval or '8'-shaped subcortical defects. The pits were usually seen as mild radiolucent areas on radiographs, soft-tissue attenuation with a thin sclerotic rim and a focal cortical perforation on CT and three different signal intensities on MRI. Only one of eight pits revealed mild focal increased uptake on bone radionuclide scans. CONCLUSION: The occurrence of a herniation pit of the femoral neck correlates closely with the particulars of the structure of the hip joint and corresponding mechanical forces. Round or oval subcortical defects surrounded by a thin sclerotic rim in the superior lateral part of the femoral neck or the anterior lateral base of the femoral head, which are usually normal on radionuclide imaging and have focal cortical perforations on CT, are specific signs for diagnosing herniation pits of the femoral neck.

[Evaluation of microvessel density and vascular endothelial growth factor in colorectal carcinoma with 64-multidetector-row CT perfusion imaging].

OBJECTIVE: To evaluate the correlation of 64-multidetector-row CT (64MDCT) perfusion imaging with microvessel density(MVD) and vascular endothelial growth factor(VEGF) in colorectal carcinoma. METHODS: 64MDCT perfusion imaging was performed in 33 patients with pathologically verified colorectal carcinoma. Time-density curves (TDC) were created from the region of interest (ROI) drawn over the tumor, target artery and vein by 64MDCT with perfusion functional software. The individual perfusion maps generated were for blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability-surface area product (PS). MVD and VEGF expression of surgical specimens were examined by immunohistochemical staining with anti-CD34, anti-VEGF monoclonal antibody. MVD and VEGF were compared among the different types of TDC in colorectal carcinoma. The correlation of CT perfusion parameters with MVD and VEGF was also examined. RESULTS: TDC of colorectal carcinoma was divided into five types according to their shapes. MVD in the colorectal carcinoma was 22.61+/-9.01. VEGF staining was found in 25 of 29 tumors (86.2%). The score of VEGF expression was 4.15+/-1.09. No significant differences of MVD and VEGF expression among TDC types were found (F=2.59, 1.11, P>0.05). There were also no correlations of MVD and VEGF expression with any dynamic CT parameters (P>0.05). CONCLUSION: 64MDCT perfusion imaging, MVD and VEGF may reflect angiogenic activity, but no significant correlations are found among them.

[MRI and CT diagnosis of rhabdomyosarcoma in the extremities:a report of nine cases].

BACKGROUND & OBJECTIVE: Imaging studies on rhabdomyosarcoma in the extremities have seldom been reported. This study was to explore the MRI and CT features of rhabdomyosarcoma in the extremities. METHODS: MRI and CT data of 9 patients with rhabdomyosarcoma in the extremities were analyzed. RESULTS: Among the 8 cases that received MRI examination, as compared with muscle, all tumors showed mixed low and intermediate signal intensity on T1WI, with the later being predominant; all tumors showed intermingling areas of hyper-, iso-, and/or hypo-signal intensity on T2WI; after Gd-DTPA injection, all tumors showed strong and heterogeneous enhancement. Five of them showed ill-defined margin and surrounding edema, the other 3 were well-circumscribed without conspicuous edema. Of the 3 cases that received CT examination, all tumors showed both low and intermediate density as compared with muscle on un-enhanced images, with the later being predominant; none of them showed calcification; 2 of them were ill-defined and the other 1 was well-circumscribed. The case that received contrast-enhanced CT examination showed strong and heterogeneous enhancement. Among all 9 cases, 8 showed necrosis or cystic changes, none showed hemorrhage and invasion of adjacent bone, but 3 showed adjacent blood vessel encasement and 1 showed tumor thrombosis in the adjacent vein. CONCLUSION: When MRI or CT reveals a soft tissue mass in the extremity with necrosis and strong and heterogeneous enhancement, especially when hemorrhage, calcification and adjacent bone invasion is not present,rhabdomyosarcoma should be considered.

[CT diagnosis of various subtypes of ameloblastoma in the maxillomandibular region].

BACKGROUND & OBJECTIVE: Based on biological behavior and histopathologic characteristics, ameloblastomas in the maxillomandibular region can be divided into several subtypes with different prognosis. This study was to explore the clinical and CT imaging features of solid or multicystic ameloblastoma (SMA), unicystic ameloblastoma (UA), and malignant ameloblastoma (MA), and thus to improve the CT diagnostic accuracy for these diseases. METHODS: Clinical and CT features of 25 histologically proven ameloblastomas in the maxillomandibular region, including 14 SMAs, 6 UAs, and 5 MAs were analyzed retrospectively. RESULTS: The median age of the patients initially diagnosed as SMA, UA, and MA were 33.5, 20.5, and 56 years, respectively. The mean maximal transverse diameters on CT images were 33 mm for SMA, 46 mm for UA, and 59 mm for MA. Of the 14 SMAs, 11 (79%) showed low to intermediate density as compared with muscles, 3 (21%) showed homogenous and intermediate density; 12 (86%) appeared as lobulate lesions; 10 (71%) had incomplete bone septa; 9 (64%) showed root resorption of the neighboring teeth; 13 (93%) showed cortical perforation; 6 (43%) had soft tissue masses; all SMAs showed well-defined margins. Of the 11 SMAs examined by enhanced studies, 9 (82%) showed strong enhancement. CT images of the 6 UAs showed homogenous and low density in comparison with muscles. Of the 6 UAs, 2 (33%) were lobulate, 4 (67%) were regularly round or oval; 1 (17%) had bone septa, 2 (33%) had root resorption of the neighboring teeth, 3 (50%) had cortical perforation. All UAs showed well-circumscribed margins without soft tissue masses. Three UAs were examined by enhanced studies and showed mild to moderate enhancement of the wall. Of the 5 MAs, 3 (60%) showed low to intermediate density as compared with muscles, 2 (40%) showed homogenous and intermediate density; 3 (60%) had bone septa; 3 (60%) showed root resorption or destruction of the neighboring teeth. All 5 MAs were lobulate with cortical perforation, soft tissue masses, and ill-defined margins. All 3 MAs examined by enhanced studies showed strong enhancement. CONCLUSIONS: SMAs are usually seen in middle-aged patients. CT images of SMAs frequently show lobulate lesions with strongly enhanced solid and cystic components. UA occurs mostly in young patients, and typically appears as cystic lesion with mild to moderate enhancement of the wall on CT images. MA often appears in old patients, and shows extensive bone destruction, soft tissue mass, ill-defined margin, and strong enhancement on CT images. Combined analysis of CT images and clinical data is helpful in differentiating these 3 subtypes of ameloblastoma.

[Imaging features of lung carcinoma, pulmonary tuberculoma, and inflammatory pseudotumor on helical incremental dynamic CT scan--a report of 44 cases].

BACKGROUND & OBJECTIVE: Lung carcinoma, pulmonary tuberculoma, and inflammatory pesudotumor are the most common solitary pulmonary nodules (SPN). Computed tomography (CT) is the major diagnostic examination of them. Most recent reports focused on their morphologic features on CT. The differential diagnoses are still difficult. This study was to explore their imaging features on helical incremental dynamic CT scan according to the differences of their hematal supply, and get more information for the diagnosis and differential diagnosis. METHODS: Incremental dynamic CT scan was performed on 115 cases of solitary pulmonary nodule. Of the 44 cases proved by postoperative pathology, 30 were lung carcinoma, 7 were pulmonary tuberculoma, and 7 were inflammatory pesudotumor. RESULTS: Of the 30 cases of lung carcinoma, 7 were mildly enhanced, 14 were moderately enhanced, 5 were highly enhanced, 2 were remarkably enhanced, and 7 were not enhanced; 9 had peak enhancement began at 18-28 s after injection, 17 began at 30-39 s, and 4 began at 40-44 s, with an average time of 32 s. Of the 7 cases of tuberculoma, 5 were not enhanced, and 2 were cricoid enhanced. All the 7 cases of inflammatory pesudotumor were remarkably enhanced, with the peak enhancement value of over 100 Hu in all cases; the peak enhancements began at 26 s, 28 s, 30 s, 32 s, 33 s, 110 s, and 122 s, respectively, after injection. CONCLUSION: Helical incremental dynamic CT is helpful in differential diagnoses of lung carcinoma, pulmonary tuberculoma, and inflammatory pesudotumor.

[Comparative study of barium enema, computed tomography and magnetic resonance imaging in preoperative diagnosis of colorectal carcinoma].

OBJECTIVE: To compare the diagnostic value of barium enema (BE), computed tomography (CT) and magnetic resonance imaging(MRI) in primary colorectal carcinoma. METHODS: A total of 64 patients with suspected colorectal carcinoma received BE (n=39), spiral CT (n=31) and MRI (n=42). The detective results were compared with the surgical results. RESULTS: Among 64 patients, 54 cases were pathologically proved as colorectal carcinoma. The diagnostic sensitivity of BE,CT and MRI was 96.9% ,96.2% and 97.1% ,and the overall accuracy was 92.3% 83.9 % and 90.5% respectively. The overall accuracy of CT and MRI for tumor T staging was 73.1% and 82.9% respectively. CONCLUSION: BE can be considered as a primary approach for diagnosing colorectal carcinoma, CT and MRI be necessary diagnostic approaches. Combined BE with MRI is the best choice for diagnosing of colorectal carcinoma.