Abstract
The aim of this paper is to inform about the implementation of dipyridamole vasodilator test as a possible alternative pharmacological stress, the incidence of side effects, the obtained results and its advantages and weaknesses. Material and Methods: A retrospective analysis of 20 patients (8 women and 12 men in the age range 37 to 78 years), 6 after transient ischemic attack, 14 after ischemic stroke, were examined during two years.
Patients were scanned with gamma camera Infinia Hawkeye using fan beam collimators with SPECT technique, at first in a standard way under basal conditions and afterwards within 1-13 days after dipyridamole pharmacologic stress (by iv infusion at a dose of 0.84 mg/kg into 50 ml of F1/1 within 4 min) followed by i.v. injection of 99mTc-HMPAO in the 10th minute. Side effects of dipyridamole was recorded; Syntophyllin was used as an antidote.
Differences in basal and post-stress studies were evaluated visually and semiquantitatively using NeuroGamTMSegami and Statistical Parametric Mapping. Results: Cerebrovascular reserve was normal in 9 patients (45 %), reduced in 11 patients (55 %). 8 patients (6 men, 2 women) with internal carotid artery occlusion (6 on right, 2 on left) were treated subsequently neurosurgically, 6 (75 %) of these patients were with pathological findings of cerebrovascular reserve, 2 (25 %) had normal cerebrovascular capacity. 12 remaining patients were treated conservatively, 5 (42 %) of these patients had pathological (mild reduce occurrence, complications preoperatively) and 7 (58 %) patients had normal cerebrovascular reserve.
Side effects of dipyridamole (hypotension, cough, chest tightness, headache) were recorded in 5 patiens; they decline within 2-5 minutes. Conclusion: Stress brain perfusion scintigraphy with dipyridamole administration is the appropriate test to assess vascular brain reserve.
It is non-invasive, easily accessible and it contributes to the decision of neurosurgery.