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Lower Extremities
General Hints
• Topogram: AP, 256 mm for joint studies.
• Patient positioning:
Depends on the region of examination. In general,
for bilateral studies, you should always try to posi-
tion the patient evenly whenever the patient can
comply.
• For knee scan:
Patient lying in supine position, feet first, promote
relaxation by placing Bocollo pillows between knees
and feet, bind feet together. The only exceptions are
extremely light patients. The latter can remove the
leg not being examined from the gantry by bending
it 90° at the hip and the knee and placing the bottom
of the same foot against the gantry casing.
• For ankle and feet scan:
Patient lying in supine position, feet first. Bind both
ankles together if necessary to assure the AP position
of both feet. Special positioning is not necessary
since the real time MPR could simulate any view of
secondary reconstruction.
• Retrospective reconstruction can be done:
a)Use B50s kernel for soft tissue evaluation.
b)For targeted FoV images on the affected side, it is
advisable to enter the side being examined in the
comment line.
• In case of 3D study only, use kernel B10 and at least
50% overlapping image reconstruction.
• To further optimize MPR image quality we recom-
mend that you reduce one or more of the following:
collimation, reconstruction increment, and slice
width for image reconstruction.