Clinical Application Of Dual Energy CT In Nasal Cavity And Paranasal Sinus Masses

Part ?The value of single energy image combined with iterative algorithm in demonstration of nasal cavity and sinus massesObjective:To explore the value of single energy image combined iterative algorithm in demonstration of nasal cavity and paranasal sinus masses.Methods:A total of 60 patients with nasal and sinus masses who underwent dual-energy CT enhanced scan in our hospital from September 2017 to June 2019 were confirmed by postoperative pathology.The dual-energy data was transferred into the post-processing software to obtain a single energy image of 40?190keV.The 50?80keV combined SAFIRE reconstruction group was selected as the experimental group,with an interval of 5keV between the 7 groups;the control group was 120KV fusion image combined FBP.The Kruskal-Wallis H test was used to compare the subjective evaluation(image quality score,lesion significance score)and objective evaluation indicators(lesion SNR,CNR,and background noise SD value)of each group.If the differences are statistically significant,further pairwise comparison between groups and correct P value by Bonferroni method.Results:The lesion SNR and CNR in the 55keV group were higher than those in the other groups,and the differences were statistically significant(P<0.05).The SD value and lesion significance score in the 55keV group were lower than those in the 50keV group,the difference was not statistically significant(P>0.05),higher than the 60keV,65keV,70keV,75keV,80keV,the difference was statistically significant(P<0.05);the image quality score of the 55keV group was higher than other groups,the difference was statistically significant(P<0.05).Conclusions:55keV single energy image combined with iterative algorithm can improve the image quality while improving the CNR of nasal cavity and sinus mass,and it is more conducive to the analysis and diagnosis of nasal cavity and sinus masses.Part ?The value of quantitative parameters of dual energy CT iodine map in differentiating nasal cavity and paranasal sinus massesObjective:To explore the application value of the quantitative parameters of iodine map in arterial phase of dual energy CT in differentiating nasal cavity and paranasal sinus masses.Methods:A retrospective analysis of 80 patients with double-energy CT enhanced scan and confirmed by postoperative pathology of nasal sinus masses.According to the pathological results,they were divided into polyp group(26 cases),benign tumor group(24 cases)and malignant tumor group(30 cases),the iodine concentration,standardized iodine concentration and Overlay value of the lesion in arterial phase were measured and calculated separately.The Kruskal-Wallis H test was used to compare the differences of the parameters between the three groups,and the ROC curves were plotted for the parameters that were different,and the effectiveness of each parameter in the differential diagnosis of nasal cavity and sinus masses was evaluated.Results:The iodine concentration,standardized iodine concentration and Overlay value of the benign tumor group and the malignant tumor group were higher than those of the polyp group(P<0.05).The iodine concentration and standardized iodine concentration in the malignant tumor group were higher than those in the benign tumor group(P<0.05),while the Overlay value was not significantly different between the two groups(P>0.05).The arterial phase iodine concentration,standardized iodine concentration and Overlay value were used to identify the AUC of nasal sinus mass-like polyps and tumors were 0.952,0.850 and 0.910(P=0.000).The AUC of the iodine concentration in arterial phase was the largest,and the iodine concentration of 1.15 mg/ml in arterial phase was used as the diagnostic threshold.The diagnostic sensitivity was 81.50%and the specificity was 96.20%.The AUC of arterial iodine concentration and normalized iodine concentration to distinguish benign and malignant tumors in nasal cavity and sinus were 0.771(P=0.001)and 0.749(P=0.002).The AUC of iodine concentration in arterial phase was the largest,with an iodine concentration of 1.45mg/ml is the diagnostic threshold,and its diagnostic sensitivity is 60.00%and specificity is 91.70%.Conclusions:The dual-energy CT arterial phase iodine-related quantitative parameters has certain value in the differential diagnosis of nasal sinus mass-like polyps and tumors.Iodine concentration can more accurately reflect the blood supply of nasal cavity and sinus masses,and it is helpful for the differential diagnosis of benign and malignant tumors in nasal cavity and paranasal sinus.Part ?Energy spectrum curve to distinguish nasal cavity and sinus mass-like polyps from tumorsObjective:To explore the value of dual-energy CT energy spectrum curve slope(k)in distinguishing nasal cavity and sinus mass-like polyps from tumors.Methods:This study enrolled 98 patients with nasal sinus masses who completed dual-energy CT enhanced scan before the operation,all patients were confirmed pathologically.According to pathological types,the patients were divided into polyp group(33 cases),benign tumor group(26 cases)and malignant tumor group(39 cases).The slope of energy spectrum curve in arterial phase(K40?70kev?K70?100keV?K100?140keV)between the three groups were compared.98 cases were further divided into polyp group(33 cases)and tumor group(65 cases),ROC curves were drawn to evaluate diagnostic efficacy.Results:The slope of energy spectrum curve in arterial phase within the three energy segments(40?70keV?70?100keV?100?140keV),both the benign tumor group and the malignant tumor group were higher than the polyp group(P<0.05),and the malignant tumor group was higher than the benign tumor group(P<0.05).The AUC of the slope at the three energy segments in distinguishing nasal sinus mass-like polyps from tumors was 0.982?0.916 and 0.932(P=0.000);the 40?70keV energy segment was the largest,K40?70keV=1.31 as cutoff value,the sensitivity and specificity were 96.90%and 97.00%.Conclusions:The slope of dual-energy CT energy spectrum curve can increase the detection rate of tumorous lesions in the nasal cavity and sinuses,especially K40?70kev has better diagnostic efficacy,which is helpful to distinguish nasal cavity and sinus mass-like polyps from tumors.