technetium-tc-99m-bicisate and Carotid-Artery-Diseases

Parent artery occlusion with/without bypass surgery is one of the treatment choices for the internal carotid artery (ICA) aneurysm difficult to treat by clipping or coiling. There have been few reports regarding postoperative cerebral blood flow (CBF) changes after surgery. This study evaluated the present bypass selection strategy based on balloon test occlusion (BTO) in terms of clinical and hemodynamic outcomes.. Twenty-one consecutive patients with ICA aneurysms underwent parent artery occlusion. High flow bypass (n=9), superficial temporal artery-middle cerebral artery bypass (n=10), or no bypass (n=2) was performed depending on the changes in clinical symptoms and CBF during BTO. Quantitative CBF measurement with acetazolamide challenge was performed in the chronic stage.. Overall outcome at discharge was good recovery 18, moderate disability 2, and severe disability 1. Two patients suffered symptomatic embolic or perforator infarction associated with the surgical manipulations. Preoperative cranial nerve pareses improved completely or partially in all patients except one. CBF in the chronic stage (n=18) demonstrated no significant difference between the surgical and non-surgical cerebral hemispheres. No cerebral ischemic event was observed during the follow-up period (mean 2.9 years).. The present surgical strategy based on preoperative BTO provides a reliable tool to achieve acceptable clinical and hemodynamic outcomes in patients with complex ICA aneurysms to be treated by parent artery occlusion.

Topics: Acetazolamide; Adult; Aged; Aged, 80 and over; Aneurysm; Angiography; Carotid Artery Diseases; Carotid Artery, Internal; Catheterization; Cerebrovascular Circulation; Cysteine; Diuretics; Female; Hemodynamics; Humans; Male; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Vascular Surgical Procedures

The purpose of this study was to evaluate the usefulness of SPECT during temporary carotid balloon occlusion testing and to evaluate the changes in regional cerebral blood flow (CBF) and regional cerebral perfusion reserve (CPR) after permanent carotid occlusion.. Temporary balloon occlusion testing was performed on 40 patients (24 head and neck tumors, 16 aneurysms). During the balloon occlusion (total time, 30 min), (99m)Tc-ethylcysteinate dimer (ECD) was injected intravenously about 5 min before balloon deflation, followed by SPECT data acquisition. SPECT images were visually evaluated, and the severity of hypoperfusion on the occluded side was classified using 4 grades (normal, mild, moderate, and severe). The count ratio of the occluded side to the contralateral side (L/N ratio) was also analyzed. In 7 patients who subsequently underwent permanent carotid occlusion, CBF and CPR were quantitatively assessed using (133)Xe inhalation dynamic SPECT at rest and after acetazolamide (ACZ) enhancement (CPR was defined as the percentage increase in CBF after ACZ), and the patients were followed up periodically.. SPECT after temporary occlusion showed moderate or severe hypoperfusion in 12 patients, whereas neurologic deterioration was observed in only 4 patients. The L/N ratios were 0.96 +/- 0.03 in normal perfusion (13 patients), 0.93 +/- 0.03 in mild hypoperfusion (15 patients), 0.83 +/- 0.03 in moderate hypoperfusion (10 patients) and 0.66 +/- 0.09 in severe hypoperfusion (2 patients) (P < 0.0001). In the 7 patients who underwent permanent carotid occlusion, CPR decreased after surgery (35% +/- 7% vs. 7% +/- 14%, P < 0.05), even though the resting CBF did not change (54 +/- 8 mL/100 g/min vs. 52 +/- 6 mL/100 g/min, not statistically significant). The steal phenomenon (rCPR < 0%) was observed in 3 patients, 1 of whom experienced transient hemiparesis when blood pressure dropped soon after surgery. On follow-up, the decreased CPR gradually improved and no infarction developed.. SPECT is useful to detect cerebral hypoperfusion during carotid occlusion. Assessment of CPR is recommended to predict the potential risk of postsurgical complications and to follow up patients after permanent carotid occlusion.

Topics: Adult; Aged; Arterial Occlusive Diseases; Balloon Occlusion; Brain; Carotid Artery Diseases; Cerebrovascular Circulation; Cysteine; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon