The measurement,spatial stereotaxis and clinical significance of optical canal:Multi-slice spiral CT study

Objective:To investigate a accurate radiologic method for the measurement and spatial stereotaxis of optic canal.Methods:20 cadaveric skulls were scanned under Multi-slice spiral CT(MSCT) according to the baseline from nasal processus to clinoideus anterior.The imaging results of of optic canal and its adjacent structures were analyzed and compared with that of gross anatomy,for verifying the accuracy of the location of optic canal on CT.Results:①The scan plane from nasal processus to clinoideus anterior accorded with optic canal completely;②Locating mark of optic canal on MSCT images accorded with that of dissection results completely,which was all synchronously displayed by three-dimensional reconstruction images in the sagittal lateral wall of sinus;③The distances of orbital aperture to nasal columella,intracranial interior opening to nasal columella and the length of optic canal interior wall were(77.84±3.60)mm,(77.35±3.22)mm,(84.28± 4.46)mm,(84.04±4.58)mm and(10.23±1.31)mm,(10.02±1.24)mm respectively.There was no significant difference for measured values between radiology and anatomy(P0.05).Conclusions:By MSCT,the baseline from nasal processus to clinoideus anterior,and three-dimensional image workstations technology,we could precisely observe,measure and locate optic canal and it's adjacent structures.