ro-16-0154 and Arterial-Occlusive-Diseases

The aim of the present study was to determine whether early and late/early images on 123I-iomazenil (IMZ) single-photon emission computed tomography (SPECT) correlate with cerebral blood flow (CBF) images and oxygen extraction fraction (OEF) images on PET, respectively, in the cerebral cortex of patients with chronic unilateral middle cerebral artery or internal carotid artery occlusive disease.. In 20 normal individuals and in 68 patients, CBF and OEF were assessed using 15O-PET, and brain SPECT scans were initiated immediately after (early images) and 180 min after (late images) the administration of 123I-IMZ. A region of interest was automatically placed in the middle cerebral artery territory in both cerebral hemispheres using a three-dimensional stereotaxic region of interest template, and the ratio of the value in the affected side to that in the contralateral side was calculated in each image.. Among patients, a significant positive correlation was observed between PET-CBF ratios and the SPECT-early IMZ ratios (r=0.797, P<0.0001) as well as between the PET-OEF ratios and the SPECT-late/early IMZ ratios (r=0.679, P<0.0001). When an abnormally elevated PET-OEF ratio was defined as a value greater than the mean+2 SD obtained in normal participants, the SPECT-late/early IMZ ratios yielded 100% sensitivity and 93% specificity, with 76% positive-predictive and 100% negative-predictive values for detecting abnormally elevated PET-OEF ratios.. Early and late/early images on 123I-IMZ SPECT correlate with CBF images and OEF images on PET, respectively, in the cerebral cortex of patients with chronic unilateral major cerebral artery occlusive disease.

Topics: Adult; Aged; Arterial Occlusive Diseases; Carotid Artery, Internal; Cerebral Arterial Diseases; Cerebral Cortex; Cerebrovascular Circulation; Female; Flumazenil; Humans; Male; Middle Aged; Middle Cerebral Artery; Positron-Emission Tomography; Tomography, Emission-Computed, Single-Photon

The aim of the present study was to determine whether central benzodiazepine receptor binding potential (BRBP)/cerebral blood flow (CBF) or a combination of CBF and cerebrovascular reactivity (CVR) to acetazolamide on single-photon emission computed tomography (SPECT) more accurately detects misery perfusion, indicating elevation of absolute value of oxygen extraction fraction (OEF) on positron emission tomography (PET), in patients with unilateral major cerebral artery occlusive diseases.. In 84 patients, OEF, CBF, CVR to acetazolamide, and BRBP were assessed using ¹⁵O-PET and N-isopropyl-p-[¹²³I]-iodoamphetamine and [¹²³I]-iomazenil SPECT, respectively. A region of interest was automatically placed in the middle cerebral artery territory using a 3-dimensional stereotactic region of interest template.. Sensitivity, specificity, and positive and negative predictive values for the affected side-to-contralateral side asymmetry on SPECT-BRBP/CBF to detect the abnormally elevated PET-OEF in the affected hemisphere were 100%, 86.4%, 66.7%, and 100%, respectively. Area under the receiver operating characteristic curve in detecting the abnormally elevated PET-OEF in the affected hemisphere did not differ between analysis of the combination of SPECT-CBF and SPECT-CVR in the affected hemisphere (0.89; 95% confidence interval, 0.80-0.94) and that of the affected side-to-contralateral side asymmetry on SPECT-BRBP/CBF (0.93; 95% confidence interval, 0.86-0.97). The combination of the 3 detected abnormally elevated PET-OEF with 97.0% specificity and 90.0% positive predictive value.. The accuracy of central BRBP/CBF asymmetry on SPECT is equivalent to that of the combination of CBF and CVR to acetazolamide on SPECT for detecting misery perfusion in patients with unilateral major cerebral artery occlusive disease.

Topics: Acetazolamide; Adult; Aged; Aged, 80 and over; Area Under Curve; Arterial Occlusive Diseases; Carbonic Anhydrase Inhibitors; Cerebral Angiography; Cerebral Arterial Diseases; Cerebrovascular Circulation; Female; Flumazenil; Humans; Iofetamine; Magnetic Resonance Imaging; Male; Middle Aged; Oxygen Radioisotopes; Positron-Emission Tomography; Predictive Value of Tests; Radiopharmaceuticals; Receptors, GABA-A; ROC Curve; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Oxygen extraction fraction (OEF) is a key predictor of stroke recurrence in patients with symptomatic major cerebral arterial occlusive disease. The purpose of the present study was to compare central benzodiazepine receptor binding potential (BRBP) and cerebral blood flow (CBF) images on SPECT with OEF images on PET in patients with chronic unilateral middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease.. OEF, CBF, and BRBP were assessed using (15)O PET and N-isopropyl-p-(123)I-iodoamphetamine and (123)I-iomazenil SPECT, respectively, in 20 healthy subjects and in 34 patients with unilateral MCA or ICA occlusive disease. All images were transformed into the standard brain size and shape by linear and nonlinear transformation using statistical parametric mapping for anatomic standardization. A region of interest (ROI) was automatically placed according to the arterial supply using a 3-dimensional stereotactic ROI template, and the ratio of the value in the affected side to that in the contralateral side was calculated in each image.. Among patients with occlusive disease, a significant positive correlation was observed between PET OEF and SPECT BRBP/CBF ratios in 3 cerebral cortical regions (r = 0.851, P < 0.0001, for anterior cerebral artery [ACA] ROI; r = 0.807, P < 0.0001, for MCA ROI; and r = 0.774, P < 0.0001, for posterior cerebral artery [PCA] ROI), but there were no correlations between these 2 parameters in the basal ganglia or the cerebellum. When an abnormally elevated PET OEF ratio was defined as a value greater than the mean + 2 SDs obtained in healthy subjects, sensitivity and specificity were, respectively, 100% and 96% for the ACA ROI, 100% and 89% for the MCA ROI, and 100% and 93% for the PCA ROI for the SPECT BRBP/CBF ratio for detecting an abnormally elevated PET OEF ratio.. BRBP/CBF images on SPECT correlate with OEF images on PET in a specific clinical setting-that is, in the cerebral cortex of patients with chronic unilateral MCA or ICA occlusive disease.

Topics: Adult; Aged; Arterial Occlusive Diseases; Basal Ganglia; Carotid Stenosis; Cerebellum; Cerebral Cortex; Cerebrovascular Circulation; Female; Flumazenil; Humans; Image Processing, Computer-Assisted; Infarction, Middle Cerebral Artery; Intracranial Arterial Diseases; Iofetamine; Magnetic Resonance Imaging; Male; Middle Aged; Oxygen Consumption; Oxygen Radioisotopes; Positron-Emission Tomography; Radiopharmaceuticals; Receptors, GABA-A; Tomography, Emission-Computed, Single-Photon

We report two patients with occlusive cerebrovascular disease who were examined by means of benzodiazepine receptor SPECT(BZR-SPECT) with 123I-iomazenil (IMZ) before extracranial-intracranial bypass surgery (EC/IC bypass). Preoperative low perfusion areas detected by cerebral blood flow SPECT (CBF-SPECT) were divided into two parts on BZR-SPECT images. In the low perfusion areas where the BZR were preserved, regional cerebral blood flow (rCBF) increased on postoperative CBF-SPECT, but where the BZR were not preserved, rCBF did not increase on postoperative CBF-SPECT. On visual inspection, the SPECT images of postoperative CBF-SPECT appeared similar to those of preoperative BZR-SPECT. For evaluation of the ischemic brain condition itself, instead of the cerebral metabolism, the distribution and activity of cerebral neurons indicated by BZR-SPECT with IMZ might be utilized.

Topics: Aged; Arterial Occlusive Diseases; Brain; Carotid Artery, Internal; Carotid Stenosis; Cerebral Arterial Diseases; Cerebral Infarction; Cerebral Revascularization; Flumazenil; Humans; Iodine Radioisotopes; Male; Middle Aged; Middle Cerebral Artery; Radiopharmaceuticals; Receptors, GABA-A; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Treatment Outcome

We report a case of 61-year old man who was suffering from cerebrovascular disease with right hemiparesis and received I-123 iomazenil (IMZ) SPECT prior to carotid endoarterectomy. Severe stenosis of the right internal carotid artery and occlusion of the left middle cerebral artery (MCA) were revealed by cerebral angiography, and a hypoperfused area in left MCA territory and crossed cerebellar diaschisis (CCD) on I-123 IMP SPECT was demonstrated. In contrast, IMZ SPECT showed symmetric normal distribution. After the carotid endoarterectomy, the hypoperfused area in left MCA territory on IMP SPECT and hemiparesis had improved. It is thought that IMZ SPECT can be a useful tool for the prediction of improvement of cerebral perfusion and the clinical outcome.

Topics: Arterial Occlusive Diseases; Brain; Carotid Artery, Internal; Carotid Stenosis; Cerebral Arterial Diseases; Cerebral Infarction; Cerebrovascular Circulation; Endarterectomy, Carotid; Female; Flumazenil; Functional Laterality; Humans; Iodine Radioisotopes; Male; Middle Aged; Paresis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Treatment Outcome