RT Journal Article
SR Electronic
T1 Improved Detection and Localization of Lower Gastrointestinal Hemorrhage Using Subtraction Scintigraphy: Clinical Evaluation
JF Journal of Nuclear Medicine Technology
JO J. Nucl. Med. Technol.
FD Society of Nuclear Medicine
SP 105
OP 111
DO 10.2967/jnmt.106.037044
VO 35
IS 2
A1 Geoffrey M. Currie
A1 Philip A. Towers
A1 Janelle M. Wheat
YR 2007
UL http://tech.snmjournals.org/content/35/2/105.abstract
AB Does subtraction scintigraphy improve the diagnostic utility of scintigraphic evaluation in acute lower gastrointestinal hemorrhage? Methods: This research was a retrospective clinical study using a repeat-measures design of randomized control and experimental groups. A single patient dataset provided both the control group (conventional scintigraphy) and the experimental group (conventional and subtraction techniques). Forty-nine raw 99mTc-red blood cell studies were randomized and interpreted by 4 independent physicians as conventional scintigraphy data only (round 1). The conventional scintigraphy studies were combined with subtraction images and randomized for reinterpretation (round 2). Results: Although there was a decrease in the mean, no statistically significant difference was noted between the mean time to bleed detection between interpretive rounds 1 and 2 (P = 0.524). The addition of subtraction scintigraphy to the interpretation process changed the outcome from “probably present” to “absent” for 14% of patients and from “equivocal” to “absent” for another 12%, and this change had a marked effect on the false-positive rate. The false-positive rate decreased from 9.6% in round 1 to 3.6% in round 2. Receiver operator characteristic analysis showed that combining conventional scintigraphy with subtraction scintigraphy improved test performance. Conclusion: False-positive studies can be reduced by using subtraction scintigraphy in conjunction with conventional scintigraphy in the interpretive process.