الفهرس 
AnatomyOnly 14 pages are availabe for public view
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Abstract
Duplex instrumentation has become remarkably
sophisticated and the latest advancement ColorDuplex
Sonography, is dramatic indeed. With Color
Duplex Imaging, blood flow information IS
superimposed in color on the B-mode U/S image,
permitting the visual assessment of blood flow. This
technology has already affected duplex examination
techniques significantly, and the clinical application of
color-duplex are sure to have wide ranging effect
(Zwiebel W.J., 1992).
Color Doppler Imaging of the orbit shows
promise in evaluation of several types of orbital
abnormalities. The most prom1smg use is for
evaluation of vascular disorders. Screening for orbital
vances and cavernous-carotid fistulae iseasily
accomplished.
Color Doppler Imaging can also be useful in
diagnosis of ocular ischemia, central retinal vessel
occlusion, and anterior ischemic optic neuropathy. In
cases of inflammatory disease it may be helpful in
searching for complications of infection and in
monitoring the size of fluid collections. In cases of
tumors, Color Doppler Imaging can be used to monitor
lesion size and in surgical planning. More work needs
to be done to determine the role of Color Doppler Imaging in evaluation of trauma and congenital
abnormalities.
An understanding of the basic anatomy of the
orbit, examination techniques, and common disease
processes in the orbit will allow the radiologist to offer
this potentially valuable modality to referring
clinicians (Belden C.J. et al., 1995).
With Color Doppler Imaging, it is now possible to
obtain reproducible information regarding blood flow
velocities in the central retinal artery and to a lesser
degree, in the short posterior ciliary arteries.
In Doppler Ultrasonography, the association of
lower flow velocities, particularly end diastolic
velocity, with higher resistive index probably reflects
an increased down stream resistance. This lower blood
flow velocity found in patients with glaucoma could,
however be a primary change or just secondary to the
disease process (Nocolela- Marcelo T., et al., 1996).
The interpretation of the results of any blood
flow analysis of the eye in the human must be
performed with care because of the complex
interaction of various parameters in haemodynamics.