Capintec CAPTUS 2000, Руководство пользователя

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CAPINTEC, INC CAPTUS
®
2000
of Interest have been defined for three isotopes, I-131, I-123, or Tc-99m. If normal values
have been entered, then results exceeding these values will be flagged. All of the patient
information may be printed. The thyroid uptake software has been designed to
accommodate a variety of different counting protocols, using either capsules or liquid
dosages.
Wipe Test
The Wipe Test measures radioactive contamination for nuclear medicine departments and
laboratories, as mandated by state and federal radiation safety requirements.
Lab Tests – Urine
Schilling Test
The Schilling Test utilizes Cobalt 57 labeled Vitamin 12 and is used to determine B-
12 deficiencies from either malabsorption, lack of intrinsic factor (pernicious anemia),
or intraintestinal destruction. The test entails collection of urine for 24 or 48 hours
after the oral administration of radioactive labeled vitamin B-12. The ratio of excreted
to administered Co57 is calculated. If the initial results indicate a reduced amount of
excreted vitamin, the test is repeated with a second sample of labeled B-12 and
intrinsic factor. For Schilling Test I, abnormal results are generally less than 8%-10%.
Normal range is generally 11% to 26%. For Schilling Test II, no change indicates
malabsorption, while an improved percentage indicates pernicious anemia.
DICOPAC
®
Test
The DICOPAC
®
Test utilizes Cyanocobalamin Cobalt 57 (Co57 labeled Vitamin B-12)
bound to Human Gastric Juice (Intrinsic Factor), and Cyanocobalamin Cobalt 58
(Co58 labeled Vitamin B-12). The test is used to determine B-12 deficiencies from
either malabsorption, lack of intrinsic factor (pernicious anemia), or intraintestinal
destruction. With the administration of both isotopes simultaneously, the DICOPAC
®
Test accomplishes the equivalent of both the Schilling Test I and Schilling Test II at
the same time. The test entails collection of urine for 24 hours after the oral
administration of radioactive labeled vitamin B-12 capsules.
The ratio of excreted to administered Co57 and Co58, and the Co57/Co58 ratio is
calculated. Malabsorption syndromes not caused by lack of intrinsic factor yield
below normal results for both Co57 and Co58 excretion, and a 57/58 ratio of about 1.
Patients with pernicious anemia have decreased Co58 excretion, low normal to
normal Co57 excretion, and an increased 57/58 ratio which generally exceeds 1.4.
The algorithm used in the DICOPAC
®
calculation finds the net counts above any
background. The background can be caused by other sources (or other peaks from
the same source). Therefore, this algorithm eliminates spillover. The algorithm
begins after the centroid of the peak is found. The endpoints of the peak are the
hwtm (half width-tenth maximum) on either side of the centroid. The background is
found from the 5 points on either side of the peak.
July 00 FUNCTIONAL & TECHNICAL DESCRIPTION 2-7