Rhese Method: Parieto-Orbital oblique Position – Optic Canal (Foramen)
Film: 8×10 in (18×24 cm)
Position of Patient:
-Patient in prone or sealed-erect position,
-with arms in the comfortable position
-shoulders lie in the transverse plane.
Position of part:
-Rest the zygoma, nose and chin of the affected at the table center and the cassette.
-AML is perpendicular MSP forms an angle of 53˚ with the plane of film
-If rotation is correct, MSP is parallel to the protractor set to 53˚
-AML position is check with one of the right side of the triangle
-Immobilize head and respiration suspended for the exposure
Directed perpendicular through the affected orbit closest to the film
-Optic canal is in cross-section and lying in the inferior and lateral quadrant of orbital shadow.
-Lateral duration indicates incorrect rotation of head
-Longitudinal duration indicates incorrect angulations of AML
-Supra orbital margins lie in the same transverse line
-Both side are examined for comparison
-Optic canal lie in the inferior and lateral quadrant of the orbit
-Optic canal should be seen enface at end of the sphenoid ridge
-Entire orbital shadow should be included
-Close beam restriction of orbital region is needed