Contrastive Study Of Oblique Coronal And Traditional Coronal CT Multiplanar Reconstruction On Frontal Recess

Objective:To provide accurate image navigation map for endoscopic frontal sinus,reduce the blindness of operation in endoscopic surgery and reduce the occurrence of serious endoscopic surgery complications.Methods:20 cases(40 sides)were collected on the axial sinus CT of patients aged from 18 to 70 in Hunan Provincial People's Hospital(the First Affiliated Hospital of Hunan Normal University),7 male and 13 female.The frontal sinuses were fully developed.In this study,PHILIPS 256-slice spiral CT scanner was used.The baseline of the scae was parallel to the hard palate.The scan ranged from the superior border of the frontal sinus to the lower edge of the maxillary alveolar process.After scanning in plain mode,transferring the original images to the workstation,multi-planar recombination was applied to reorganize the oblique coronal position:first,the background CT image was adjusted to the left-right symmetry,and the thin coronal bitmap was first reconstructed;Then,in the sagittal position,the oblique coronal plane parallel to the axial position and parallel to the beak and the connective line of the nasal hypothalamus was reconstructed.This would obtain the DICOM format of thin-layer c.oronal and oblique coronal CT imaging data.(1mm layer thickness,1mm layers interval),save all the reconstructed images were send to the PASC system in our hospital,and observe the frontal sinus drainage systemwere observed through all the CT images,mainly including the agger nasi cell,the frontal ostium,and the frontal recess,Frontal sinus drainage pathway in the coronal and oblique coronal display:and the spatial relation between the agger nasi cell and frontal sinus drainage pathwayResults:1.Both the coronal position and the oblique coronal position,without the gender diffrence,the nasal agger cell appeared in the CT.2.The spatial relationship between a few nasal sgger cell and frontal sinus openings could be observed in the coronal plane,but only in the upper and lower two-dimensional spatial relationships.The spatial relationship between the frontal ostium and agger nasi cell could be clearly observed in the oblique coronal position.The spatial relationship includes three-dimensional spatial relationships such as Anterior-posterior,left-right,up-down,,and could accurately direct the relationship between the frontal sinus drainage pathway and the frontal recess to guide the precise opening during the frontal sinus surgery.Conclusion:Observed on the oblique coronal plane,the relationship between the agger nasi cell,and frontal sinus drainage pathway is clearer,and the spatial relationship is more consistent with what is seen under 70 degree endoscopic surgery.The oblique coronary position can provide the spatial relationship between the anterior and posterior,left and right of the channels providing an accurate navigation map for the opening of the frontal sinus under the 70 degree endoscope,providing more detailed information for precise opening of the frontal sinus,and would decrease severe complications during endoscopic frontal sinus surgery.