Conversion to Paradoxical Finding on Technetium-99m-labeled RBC Scintigraphy after Treatment for Secondary Raynaud’s Phenomenon

Abstract

An 18-year-old woman reported that after exposure to cold temperatures her fingers appeared blue and her hands and feet felt cold. Secondary Raynaud's phenomenon (RP) associated with peripheral vascular disease was suspected. Technetium (Tc)-99m-labeled RBC hand scintigraphy after cold change showed decreased blood pool activity in her fingers. The patient's symptoms improved after she received sarpogrelate HCL (200 mg/day) and nifedifine (40 mg/day). Follow-up scintigraphy performed 7 months after the patient started treatment showed paradoxically increased blood pool activity in her fingers after cold challenge. To the best of our knowledge, this is the first case report of a patient with secondary RP showing paradoxical change on scintigraphy after she received medication that improved her symptoms.

Perfusion Scintigraphy for the Evaluation of Patients with Raynaud’s Phenomenon

“…RP can be evaluated using perfusion scintigraphy, and there have been several studies of perfusion scintigraphy [3,[20][21][22][23][24][25]. Various radiopharmaceuticals are used, including technetium-99m (Tc-99m), diethylenetriamine pentaacetate (DTPA) [26][27][28], Tc-99m red blood cell (RBC) [20,23], Tc-99m pertechnetate [24,29], Tc-99m met hylene diphosphonate (MDP) [3], and Tc-99m hydroxymethylene diphosphonate (HDP) [22]. When the affected areas are the hands, intravenous injection of radiopharmaceuticals is done via the dorsal vein.…”

“…Perfusion scintigraphy for RP can be done with or without cold stimulation. The one-hand chilling method is widely used for cold stimulation [3,20,21,23,[25][26][27][28]. It is done by immersion of one hand (the non-dominant hand or the hand with more severe symptoms) in cold water (4°C) [22].…”

“…Dynamic blood flow images and blood pool images are obtained. However, there have been various protocols for the one-hand chilling method regarding the length of time allotted for immersion and recovery: (1) 30 s of immersion and 10 min of recovery [30], (2) 30 s of immersion and 15 min of recovery [21,22], (3) 60 s of immersion and 20 min of recovery [23], (4) 2 min of immersion with at least 10 min of recovery time [3], and (5) 5 min of immersion with 15 min of recovery [25]. Porter et al reported that the average time to recovery of normal temperature after chilling (20 s of immersion) was 10 min for the control group vs 35 min in patients with RP [31].…”

“…However, among the various studies available in the literature, there are differences in the way in which the ROI is drawn. Previous studies used two ROIs that were manually drawn on all the fingers except the thumb (similar to a hexagonal shape; not regular) and on the whole palm area [3,23,24,28]. Sarikaya et al used a regular elliptic ROI for the fingers (images were not shown in their article) [30].…”

“…For analysis, various ratios were used including blood pool images, finger-to-palm ratio (FPR) [3,23,24,28], and blood pool uptake ratios of the hand and wrist [25]. To compare the chilled vs ambient hand, a perfusion graph, initial slope ratio, first peak height ratio, and 30-s area-under-curve (AUC) ratio were employed [3,20,22,25].…”