Application Of Multi-slice CT In Nasal Sinuses And Relative Structures

Purpose:To display the nasal sinuses and interrelated structures with multi-slice CT isotropic scanning by using multi-planar reformation (MPR).And to discuss the advantage to examine the nasal sinuses and interrelated structures with multi-slice CT. Material and Method:Collect 55 cases (32 male, 23 female), age range 9 years to 75 years. Examining the nasal sinuses with multi-slice CT(SOMATOM SENSATION CARDIAC16) isotropic scanning with the following parameters: field of view, 250mm; section thickness, 0.6mm; 100mA; 120 kV; matrix,512x512;sectionthichness,0.6cm;a reconstruction increment 0.4 mm. Conduct double oblique MPR on WIZARD workstation on the primitive images of 0.6 mm in thickness by inputting the image to show the standard transverse, the coronal and the sagittal sections of the sinus. And find the most compatible plane to display the important structures (uncinate process, frontal drainage approach, nasolacrimal canal, ethmoidal infundibulum, ethmoidal bulla,frontal recess, middle turbinate, hiatus semilunaris). Analyzing the measurements we use SPSS(Statistics package for social science) 12.0 for windows. Chisquare test is applied in between sdandard plane and double oblique MPR plane to show the uncinate process, frontal drainage approach, nasolacrimal canal, ethmoidal infundibulum, ethmoidal bulla,frontal recess, middle turbinate, hiatus semilunaris. Statistical significance is assigned to a probability level of less than 0.05.Ridit analysis is applied in analyzing the drainage way of sinus and ncinate process, frontal drainage approach, nasolacrimal canal, ethmoidal infundibulum, ethmoidal bulla,frontal recess, middle turbinate, hiatus semilunaris on standard plane. Statistical significance is assigned to a probability level of less than 0.05.The mucous of sinus we also use ridit analysis on different window width and window level. Statistical significance is assigned to a probability level of less than 0.05Result:(1)It can be showed that the aerification type of the nasal sinuses and weather the structure is symmytric in the transverse plane, the coronal plane, the sagittal plane. On the sdandard transversal plane the extend aerification of frontal sinus, sphenoidal sinus and the drainage way can be showed clearly from upper to inferior. On the coronal plane the ostiomeatal complex, the middle turbinate, middle nasal meatus, maxillary sinus and its entrance were mainly observed. On the saggital plane the entrance of frontal sinus and sphenoidal sinus can be displayed.(2) Uncinate process, ethmoidal infundibulum, ethmoidal bulla, middle turbinate can be showd better on the sdandard plane than on the routine plane(P<0. 05).The frontal recess and nasofrontal duct is no statistical significance (P>0.05).(3) Some important special structures such as uncinate process, frontal drainage approach, nasolacrimal canal and the relation between the wall of the sphenoid-ethmoidal sinuses, the internal carotid artery(ICA) and the optic nerve(ON) can be observed well in the diagonal plan only.(4)To display mucous well the window level should be lowed properly.Conclusion:(1) Once scaning, we can display images of any planes after post processing. So we can reduce the radiation and difficulty of position patients.(2) the nasal sinuses and interrelated structures can be display very well after post processing with multi-slice CT isotropic scanning by using multi-planar reformation (MPR)...