Norland Elite 437A150, Operator'S Manual

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Maintaining High Quality Research Scans
Variations in subject and positioning, scan and analysis techniques can influence the precision and accuracy of
Bone Density estimations. Facilities can reduce the adverse effects of some of these factors by:
Performing and monitoring the daily QA procedure to verify that other radiation sources (x-ray machines, nuc-
lear imagers) are not affecting the performance of the Norland system. The daily QA procedure verifies
proper operation as well.
Ensuring that all operators position patients/subjects and analyze data in the same manner.
Screening patients/subjects for recent radionuclide uptake procedures. Residual emission may be mis-
interpreted by Norland Bone Densitometers as x-rays.
Screening patients/subjects for recent ingestion of radiopaque substances. Barium or other dyes used in
some x-ray procedures could result in increased soft tissue x-ray absorption.
Screening patients/subjects for prosthetic devices, implants, surgical staples, or other high density sub-
dermal materials that may affect bone density estimates.
Ensuring that patients/subjects contain no metal objects or other high density objects that might affect bone
density estimations.
Ensuring that scan and analysis parameters remain constant for all scans of the same patient or subject.
Operator's Guide
437D140 Rev. I
9-4 Research & Small Subject Scan