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PurposeTo explore the significance of dual energy CT in differential diagnosis of squamous cell carcinoma metastatic lymph nodes and lymph node tuberculosis in the neck.Material and Methods Twenty-five patients with a total of 62 cervical enlarged lymph nodes confirmed with squamous cell carcinoma metastasis or lymph node tuberculosis by pathology underwent dual energy enhanced CT scan. Iodine coverage value of two different kinds of pathological properties of lymph nodes was measured. The trend of the spectrum curve was observed and the energy spectrum curve slope of two kinds of lymph nodes were compared. The sensitivity, specificity and accuracy of energy spectrum curve slope in differential diagnosis were analyzed. Results Of all 62 lymph nodes, there were 32 squamous cell carcinoma metastatic lymph nodes and 30 lymph node tuberculosis. There were statistic significance in the iodine coverage between the squamous cell carcinoma metastatic lymph nodes and lymph node tuberculosis (t=3.806 and 3.698,P<0.05). In the range from 60 keV to 180 keV, CT value of the two kinds of lymph nodes decreased with increase of keV value. It showed the higher the keV value the less CT value decreased, with the energy spectrum curve of drop type. The area of the iodine coverage was 0.756 with the differential diagnostic sensitivity of 56% and the specificity of 80%. The area of energy spectrum curve slope was 0.898 with the differential diagnostic sensitivity of 76% and the specificity of 85%.Conclusion The iodine coverage value and the energy spectrum curve slope have significance in differential diagnosis of the cervical squamous cell carcinoma metastatic lymph nodes and lymph node tuberculosis. The energy spectrum curve slope is superior to the iodine coverage value in differential diagnosis.
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Purpose Dual-energy coronary artery CT angiography (CTA) is a very promising one-stop examine, but the radiation dose is too high to hinder the development of the technology. The aim of this article is to explore the feasibility of low tube current combined with sonogram-affirmed iterative reconstruction (SAFIRE) technology in dual energy coronary artery CTA scan. Materials and Methods One hundred and twenty patients were randomly divided into four groups according to the tube current of A ball:conventional group (180 mAs) and low-dose groups (150 mAs, 120 mAs, 90 mAs). The SAFIRE 3 reconstruction method was used in the low-dose groups. The differences of mean CT values, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), image quality score and effective dose (ED) of the four groups were compared. Results The coronary artery segment display and the mean CT value of the four groups showed no statistic difference (P>0.05), while the image quality score, noise, SNR, and CNR showed statistic difference (P0.05). The ED was (5.50±1.47) mSv, (4.55±1.16) mSv, (3.41±0.77) mSv and (2.44±0.67) mSv, respectively for the four groups, and there was statistical difference (P<0.05). ED of 90 mAs group decreased 55.62% than that of 180 mAs group. Conclusion Coronary artery CTA using 90 mAs combined with SAFIRE can significantly reduce the radiation dose without losing image quality, thus it has a good prospect of clinical application.
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Objective The purpose of this article was to investigate the diagnostic value of CT and MRI in preoperative local staging for rectal cancer patients. Methods Forty rectal cancer patients were enrolled,and their preoperative CT and MRI staging and pathological staging in T and N were compared. Results The total diagnostic accordance rate of CT staging in T was 57.5%(31/40),among which the accordance rate of T1-2,T3 and T4 was 87.5%(35/40),83.25%(33/40) and 70%(28/40),respectively. The total diagnostic accordance rate of MRI staging in T was 77.5%(31/40), among which the accordance rate of T1-2, T3 and T4 was 92.5%(37/40), 77.5%(31/40) and 85%(34/40),respectively. The differences were tested by Chi-square test,and there were no significant differences between the two groups in T staging. The sensitivity of T staging by CT was 77.78%(7/9) for T1-2, 75% (12/16) for T3 and 93.33% (14/15) for T4. Compared with CT, the sensitivity of MRI was 66.67%(6/9) for T1-2, 81.25%(13/16) for T3 and 80%(12/15) for T4, and there were no significant differences between the two groups. The specificity of T staging by CT was 90.32% (28/31) for T1-2, 45.83%(11/24) for T3 and 96%(24/25) for T4. Compared with CT, the specificity of MRI was 100% (31/31) for T1-2, 75% (18/24) for T3 and 88%(22/25) for T4, and there was a significant difference in T3 specificity ( <0.05) . The total diagnostic accordance rate of CT staging in N was 82.5% (33/40),among which the rate of N- and N+was 82.5%(33/40) and 82.5%(33/40), respectively. The total diagnostic accordance rate of MRI staging in N was 62.5%(25/40),among which the rate of N- and N+was 62.5% (25/40) and 62.5%(25/40), respectively. There were significant differences between the two groups in pelvic N staging ( < 0.05) . The sensitivity of N staging by CT was 75.00%for N- (18/24) and 81.25%(13/16) for N+. Compared with CT,the sensitivity of MRI was 75.00%(18/24) for N- and 43.75%(7/16) for N+,and there were significant differences between the two groups ( <0.05) . The specificity of N staging by CT was 81.25% (13/16) for N- and 83.33%(20/24) for N+. Compared with CT, the specificity of MRI was 43.75% (7/16) for N- and 75.00%(18/24) for N+, and there were significant differences between the two groups ( <0.05) . Conclusion MRI has a high reliability in diagnosing rectal cancer with penetrating through the muscularis propria into the placenta percreta or not, but CT is superior in diagnosing the lymphonodus metastasis.
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Objective To study the diagnostic value of contrast-enhanced CT scan with split bolus for the ureleropelvic junction obstruction(UPJO) caused by aberrant vessel of kidney.Methods 52 patients with UPJO underwent contrast-enhanced CT scan with split bolus.The aberrant vessels and its origin as well as the relationship between aberrant vessels and UPJO were observed comparatively with the results of surgery.Results In 52 cases,CT showed UPJO caused by aberrant vessl of kidney in 14 cases,including accessory renal arteries in 10,ovarian artery originated from left renal artery in one,right accessory renal artery in one and gonad veins in 2.CT findings were corresponded to operations in all these 14 cases.The sensitivity and specificity of CT in evaluating UPJO were 100% respectively.Conclusion The UPJO caused by aberrant vessel of kidney can be diagnosed accurately by contrast-enhanced CT scan with split bolus,which can be offered for surgical treatment for UPJO.The patient's CT dose can be decreased with split bolus.