CT-evaluation of the orbit

The purpose of this study is to analyse the CT images of the orbit and sella turcica compared with the thin layer sections of the cadaver. The head of an embalmed human cadaver was scanned in axial, coronal, sagittal and para-axial planes according to Reid's base line, using the GE CT/T 8800 scanner with 1.5 mm collimation. The technique of Review sup(TM) target reconstruction was applied. This technique had given detailed visualization of orbital structures as well as their anatomic relationship to each other. The cadaver was sectioned serially in axial and coronal planes 2 to 3 mm slices. The author analysed the appearances of the orbit and sella turcica in various axial and coronal sections, and then correlated the anatomic and CT appearances in corresponding planes. Based on the analysis of extraocular muscles and the optic nerve, judgements regarding their size should be based only on true cross sections, 900 to the course of the individual muscle or the optic nerve. Fractional reformations parallel to various segments allowed evaluation of tortuous orbital vessels and nerves. (author)