technetium-tc-99m-bicisate and Intracranial-Aneurysm

The aim of this study was to correlate cerebral blood flow (CBF) and mean transient time (MTT) measured on dynamic perfusion computerized tomography (CT) with CBF using (99m)Tc ethyl cysteinate dimer-single-photon emission computerized tomography (SPECT) in patients with cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH).. Thirty-five patients with vasospasm following aneurysmal SAH (12 men and 23 women with a mean age of 49.3 +/- 10.1 years) underwent imaging studies; thus, 35 perfusion CT scans and 35 SPECT images were available for comparison. The CBF and MTT values in 12 different brain regions were defined relative to the interhemispheric occipital cortex values using perfusion CT scans and were compared with qualitative relative (rel)CBF estimated on SPECT images. In brain regions with normal, mild (relCBF 71-85%), moderate (relCBF 50-70%), and severe (relCBF < 50%) hypoperfusion on SPECT, the mean relCBF values measured on perfusion CT were 1.01 +/- 0.08, 0.82 +/- 0.22, 0.6 +/- 0.15, and 0.32 +/- 0.08, respectively (p < 0.0001); the mean relMTT values were 1.04 +/- 0.14, 1.4 +/- 0.31, 2.16 +/- 0.46, and 3.3 +/- 0.54, respectively (p < 0.0001). All but one brain region (30 regions) with severe hypoperfusion on SPECT images demonstrated relCBF values less than 0.6 and relMTT values greater than 2.5 on perfusion CT scans.. Relative CBF and MTT values on perfusion CT showed a high concordance rate with estimated relCBF on SPECT in patients with vasospasm following aneurysmal SAH. Given its logistical advantages, perfusion CT may be a valuable method of assessing perfusion abnormality in the acute setting of vasospasm and in patients with an unstable condition following aneurysmal SAH.

Topics: Adult; Cysteine; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Organotechnetium Compounds; Radiography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Subarachnoid Hemorrhage; Tomography, Emission-Computed, Single-Photon; Vasospasm, Intracranial

An early 60s-year-old man suffered reversible dysfunction of the blood-brain barrier (BBB) induced by repeated injection of contrast medium during coil embolization of intracranial unruptured aneurysm. He presented with convulsion during coil embolization, and neurological symptoms of aphasia and right hemiparesis continued for 5 days, and then improved completely. All transient radiological abnormalities were limited to the territory of the left internal carotid artery, where contrast medium was injected repeatedly. Repeated computed tomography, magnetic resonance imaging, single-photon emission computed tomography, and cerebrospinal fluid test findings indicated that temporary dysfunction of the BBB might have occurred. Dysfunction of the BBB in the anterior circulation induced by contrast medium is rare. Tolerance to toxicity of contrast medium may depend on the individual patient, and repeated injection of contrast medium may cause dysfunction of the BBB, leading to toxic dysfunction directly in the brain.

Topics: Aphasia; Blood-Brain Barrier; Carotid Artery, Internal; Cerebral Angiography; Contrast Media; Cysteine; Dose-Response Relationship, Drug; Embolization, Therapeutic; Humans; Injections, Intra-Arterial; Intracranial Aneurysm; Iopamidol; Magnetic Resonance Angiography; Male; Middle Aged; Organotechnetium Compounds; Paresis; Seizures; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Topics: Adult; Cysteine; Embolization, Therapeutic; Female; Humans; Intracranial Aneurysm; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

The purpose of this prospective study was to detect symptomatic cerebral vasospasm in aneurysmal subarachnoid haemorrhage (SAH) by a non-invasive mean cerebral blood flow (mCBF) quantification using 99mTc-ethyl cysteinate dimer. Measurement of mCBF without blood sampling and single photon emission tomography (SPECT) were performed at 1 and 7 days after surgery in 35 consecutive SAH patients, of whom 16 were examined at day 30 as well. A decrease in mCBF of more than 10% on day 7 versus day 1 was considered to indicate vasospasm. On visual interpretation of SPECT, a perfusion decrease which appeared newly on day 7 was considered to indicate vasospasm. In total, nine of 35 patients had cerebral vasospasm confirmed by computed tomography (CT) and/or angiography. The mCBF measurement showed a 77.8% (7/9) sensitivity, a 88.5% (23/26) specificity, a 70.0% (7/10) positive predictive value, and a 92.0% (23/25) negative predictive value. SPECT yielded a 33.3% (3/9) sensitivity, a 73.1% (19/26) specificity, a 30.0% (3/10) positive predictive value, and a 76.0% (19/25) negative predictive value. On SPECT, decreased perfusion was observed in most of the patients at clipping sites, which might represent post-operative transient abnormal perfusion and should not be read as vasospasm. In conclusion, this mCBF measurement is more accurate than visual interpretation of SPECT for detecting vasospasm.

Topics: Adult; Cerebral Angiography; Cerebrovascular Circulation; Cysteine; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Subarachnoid Hemorrhage; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Vasospasm, Intracranial