Analysing Of Ethmoid Sinus Lamella Hierarchical Structure And Its Application In Endoscopic Sinus Surgery

Objective:To explore ethmoid sinus hierarchic and precise opening by analysing lamella hierarchical structure and its pneumatization and imp rove ethmoid opening effectiveness and reduce complication.Methods:Collecting spiral CT scan data of patients with sinus CT due to nasal discomfort or other diseases,a total of 120(240 sides)original thinlayer DICO data of sinus CT were obtained(scanning parameters were layer thickness,layer distance 0.65 mm,voltage 120 KV,Current 500mA),imported into the 3D reconstruction software ImageViewer,and perfo rmed 3D reconstruction analysis of axial position,crown position and sagittal position(set window width 2000 Hu,window level 200Hu).After accurately positioning the ethmoidal sinus I-V substrate,the localized magnification and observation of the gasification of each substrate was explored to explore its hierarchy and gasification laws.Observe the relationship between Haller air chamber,Onodi air chamber in axial position,coronal position,sagittal position and each substrate structure.The principle and method of substrate hierarchy analysis are used to guide the endoscopic sinus surgery and open the ethmoid sinus in the endoscopic sinus surgery.Results : 120 cases(240 sides)CT DICO data were collected and reconstructed for 3D analysing.The ethmoid sinnuses were composed by I-V lamellas and 55.4% of the cases presented lamella V.Potentialhierarchical spaces were existed between the lamellas.24.2% of the ethmoids sinuses presented Haller’s cell,and they were pneumatilazed from the lamella of middle turbinate or the superior turbinate16.7%,7.5%,respectively.The rate of pneumatization of superior turbinate and its lamella was 83.3%,and among which 18.3% were pneumatilazed to Onodi cells.The Onodi cells were presented in 32% of the ethmoid sinuses.The supreme turbinate and its lamella was presented in 55.4% of the sinuses,and its pneumatilization rate was 77.4%,among which 18.8%were pneumatilized to Onodi cells.Onodi cells were orignated from the lamella of superior and supreme turbinate 18.3%,10.4%,respectively.And the rest 3.3% of Onodi cells were originated from both of lamella of superior and supreme turbinate.The lamella and its corresponding pneumatilized structure composed a relatively independent air flow and drainage system and could cause local disorder by itself.In ethmoid sinus surgery,the suprior and supreme turbinate could be the landmark for safe endoscopic ethmoid sinus opening procedure.The III and IV lamella and its corresponding pneumatilized cells could be completely removed just prior to the suprior and supreme turbinate,respectively.The V lamella and coresponding pneumatilized cells also could be safely and presicely removed according to the landmark of supreme turbinate as showing by CT scan.Conclusion : The ethmoid sinus could be completely and preciselyopened by analysing and guiding of the hierarchical lamella structures.And the hierarchical,precised,standard and homogenized opening proce dure could be achieved by doing this and complications could be reduced dramatically.