R. Prakash et al., RADIONUCLIDE ANGIOGRAPHY IN EVALUATION OF COLD SOLITARY THYROID-NODULES - IMPROVED DIAGNOSTIC-ACCURACY USING FLOW AND WASHOUT ANALYSIS, Clinical nuclear medicine, 20(10), 1995, pp. 878-883
Radionuclide thyroid angiography was performed in 252 patients with hy
pofunctioning thyroid nodules to evaluate differences in vascular flow
and washout patterns in benign and malignant disease. Time activity c
urves of Tc-99m pertechnetate flow through the cold nodules were gener
ated using region of interest software. Retention ratios of counts in
the nodule at 2 minutes after radionuclide administration versus those
at peak activity were derived. Patients subsequently underwent surgic
al excision and histopathologic examination. One hundred forty-four of
the 204 benign nodules were avascular with absent radionuclide flow t
hrough the nodule. Fifty-six benign nodules were vascular with a prolo
nged radionuclide washout pattern with retention ratios ranging from 0
.60-0.92. Forty-six of the 48 malignant nodules displayed increased pe
rfusion with rapid radionuclide washout with retention ratios ranging
from 0.28-0.48. Four benign nodules exhibited a similar flow and washo
ut pattern, Radionuclide thyroid angiography with vascular flow and wa
shout analysis appears to be a useful technique to differentiate betwe
en benign and malignant thyroid nodules with a high degree of sensitiv
ity and specificity.