• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.47-55
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• 1996

Progressive supranuclear palsy (PSP) is a parkinson-plus syndrome characterized clinically by supranuclear ephthalmoplegia, pseudobulbar palsy, axial rigidity, bradykinesia, postural instability and dementia. Presence of dementia and lack of cortical histopathology suggest the derangement of cortical function by pathological changes in subcortical structures in PSP, which is supported by the pattern of behavioral changes and measurement of brain metabolism using positron emission tomography. This study was done to examine whether there are specific changes of regional cerebral perfusion in PSP and whether there is a correlation between severity of motor abnormality and degree of changes in cerebral perfusion. We measured regional cerebral perfusion indices in 5 cortical and 2 subcortical areas in 6 patients with a clinical diagnosis of PSP and 6 healthy age and sex matched controls using $^{99m}Tc$-HMPAO SPECT. Compared with age and sex matched controls, only superior frontal regional perfusion index was significantly decreased in PSP (p<0.05). There was no correlation between the severity of the motor abnormality and any of the regional cerebral perfusion indices (p>0.05). We affirm the previous reports that perfusion in superior frontal cortex is decreased in PSP. Based on our results that there was no correlation between severity of motor abnormality and cerebral perfusion in the superior frontal cortex, nonmotoric symptoms including dementia needs to be looked at whether there is a correlation with the perfusion abnormality in superior frontal cortex.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.282-292
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• 1994

Brain perfusion SPECT shows typical regional perfusion abnormalities in Alzheimer's disease(AD) and is useful for its diagnosis. However, there is also arguement that these patterns show significant overlap with other causes, and the accuracy for SPECT in differentiating AD has shown conflicting results. We postulate that the variation in re-ported results are partly due to a difference in patient or control selection with special reference to the mixture of ischemic cerebral disease in the studied population. To deter-mine the effect of ischemic lesions and the nature of control subjects on SPECT studies for AD, we performed $^{99m}Tc$-HMPAO single photon emission computed tomography (SPECT) in 11 probable AD patients with a low (<4) Hachinski ischemic score and 12 non-demented age matched controls. Magnetic resonance imaging(MRI) disclosed ischemic cerebral lesions in 27% (3/11) of the PAD group and 25% (3/12) of the control group. Regional perfusion indices were quantitated from the SPECT images as follows and the distribution of perfusion indices from both groups were compared. This was repeated with controls after excluding those with significant ischemic lesions by MRI : regional perfusion index = average regional count/average cerebellar count All PAD patients showed perfusion abnormality in SPECT. However, 53% (10/12) of controls also showed perfusion at-normalities, and no pattern could reliably differentiate the two groups. After excluding controls with significant cerebral ischemia, the difference in temporal and parietal perfusion index was increased. A decreased tempore-parietal and any parietal or temporal per-fusion index had a sensitivity of 18% and 36% in detecting AD, respectively. When using a separate group of normal age mathced controls, the indices showed an even more difference in the temporal and parietal lobes and the sensitivity of a decreased tempore-parietal and any parietal or temporal perfusion index had a sensitivity of 36% and 55% in detecting AD, respectively. Thus, the type of control with special reference to the pres-once of ischemic cerebral lesions contribute significantly to the accuracy of perfusion SPECT in diagnosing AD. This nay have particular importance in the diagnosis of AD in populations where the prevalance of cerebrovascular disease is high.

• The Korean Journal of Nuclear Medicine
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• v.26 no.2
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• pp.251-256
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• 1992

Regional cerebral blood flow were measured in 10 patients with Parkinson's disease and 12 normal persons using $^{99m}Tc-HMPAO$ SPECT. Reconstructed images were interpreted qualitatively and were compared with those findings of CT. For the quantitative analysis, six pairs of region of interest matched with the perfusion territories of large cerebral arteries and cerebellar hemisphere were determined. From the count values, indices showing the degree of asymmetry between right and left cerebral or cerebellar hemisphere, cerebral asymmetry index (ASI) and percent index of cerebellar asymmetry (PIA), and an index showing change of each region, region to cerebellum ratio (RCR) were obtained. ASI of normal persons and patients were $0.082{\pm}0.033$ and $0.108{\pm}0.062$, respectively and PIA were $-0.4{\pm}0.7%$ and $-0.7{\pm}1.0%$, respectively, which showed no statistically significant difference between normal persons and patients. Among 10 RCR's, those of both regions of basal ganglia and both regions of anterior cerebral artery were significantly reduced. We concluded that the most significant reduction of regional cerebral blood flow in patients with Parkinson's disease was observed in the regions of basal ganglia and in the regions of anterior cerebral artery, and the degree of change in hemispheric blood flow was similar in both hemisphere.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.22-30
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• 1994

Encephalo-duro-arterio-synangiosis (EDAS) is a relatively new surgical procedure for treatment of childhood moyamoya disease. We assessed regional cerebral perfusion in moyamoya patients before (1.3 mo) and after (6.8 mo) EDAS with $^{99m}Tc$-HMPAO brain SPECT. A total of 21 EDAS operations in 17 moyamoya patients was included. Preoperative CT or MRI showed cerebral infarction in 14 patients and carotid angiography showed Suzuki grade I to V stenosis in 6%, 9%, 62%, 12% and 12% of the hemispheres respectively. Preoperative SPECT showed regional hypoperfusion in all patients, bilateral frontal and temporal lobes being the most frequently involved site. $4{\times}4$ pixel sized ROIs were applied on the frontotemporal cortex in 3 slice averaged transverse tomographic images. An index of regional perfusion was measured as: PI (%)=average F-T activity/average cerebellar activity${\times}100$ Pre-EDAS ipsilateral PI ranged from 23.7 to 98.4% (mean: $74.3{\pm}17%$) and increased significantly after operation ($81.4{\pm}17%$, p<0.001). Individual post-EDAS PI improved in 15/21 cases, showed no significant change in 5 and was slightly aggravated in 1. The amount of clinical improvement (${\Delta}CI$) was graded with a scale of 0 to 4 based on frequency and severity of TIA attacks. When patients were grouped according to pre-EDAS PI, group II (PI 70-89) showed a significantly higher ${\Delta}CI$ (3.3) compared to group I (PI< 70, 1.57) or group III (PI >90, 0.5) (P< 0.001). The amount of perfusion improvement (${\Delta}PI$) showed significant correlation with ${\Delta}CI$ (r=0.42, p=0.04). ${\Delta}PI$ did not, however, correlate with the amount of neovascularization assessed angiographically in 8 patients. Serial HMPAO SPECT is an useful noninvasive study for assessing perfusion improvement after EDAS in childhood moyamoya patients.

• Journal of Acupuncture Research
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• v.21 no.1
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• pp.111-118
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• 2004

Background and purpose: Opposing-needling technique involves selecting acupoints at unaffected limb. The aim of this study was to evaluate the effect of LI4-LI11 electrical acupuncture at unaffected limb on the cerebral blood flow in ischemic stroke patients using SPECT Methods: We selected 9 ischemic stroke patients. Baseline brain SPECT was done with triple head gamma camera(MultiSPECT3, Siemens, USA) after intravenous administration of 925 MBq of Tc-99m ECD). Fifteen-minute electro-acupuncture at Hapgok(LI 4) and Gokji(LI 11) were applied on unaffected upper limb of subjects. The same dose of Tc-99m ECD was injected during the electro-acupuncture, and the second SPECT images were obtained. Using the computer software(ICON 7.1, Siemens, USA), 3 SPECT slices(upper, middle, lower) surrounding the brain lesion were selected and each slice was divided by 10-16 brain regions. Asymmetry indexes were analyzed in each brain region. We regarded$\geq$10% changes of asymmetry index between before and after electro-acupuncture as significance. Results: Seven Patients(77.8%) had significantly increased perfusion and 2(22.2%) didn't show increased perfusion in post-acupuncture scans compared to pre-acupuncture scans(baseline). The regions of CBF improvement were mostly frontal lobes and anterior temporal lobes. Conclusions: This study demonstrated that LI4-LI11 electro-acupuncture at unaffected limb increased regional cerebral blood perfusion to the corresponding brain areas in ischemic stroke patients.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.8-16
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• 2008

Purpose: To assess the effect of extracranial-intracranial (EC-IC) bypass surgery on hemodynamic improvement, we evaluated serial regional cerebral hemodynamic change of the middle cerebral artery (MCA) in symptomatic patients with atherosclerotic occlusion of the internal carotid artery (ICA) or MCA using $^{99m}Tc$-ECD acetazolamide stress brain perfusion SPECT (Acetazolamide SPECT). Materials and Methods: The patients who had suffered a recent stroke with atherosclerotic ICA or MCA occlusion underwent EC-IC bypass surgery and Acetazolamide SPECT at 1 week before and three to six months after surgery. For image analysis, attenuation corrected images were spatially normalized to SPECT templates with SPM2. Anatomical automated labeling was applied to calculate mean counts of each Volume-Of-Interest (VOI). Seven VOIs of bilateral frontal, parietal, temporal regions of the MCA territory and the ipsilateral cerebellum were defined. Using mean counts of 7 VOIs, cerebral perfusion index and perfusion reserve index were calculated. Results: Seventeen patients (M:F =12:5, mean age $53{\pm}2yr$) were finally included in the analysis. The cerebral blood flow of the parietal region increased at 1 week (p = 0.003) and decreased to the preoperative level at 3-6 months (p = 0.003). The cerebrovascular reserve of the frontal and parietal regions increased significantly at 1 week after surgery (p<0.01) and improved further at 3-6 months. Conclusion: Cerebrovascular reserve of the MCA territory was significantly improved at early postoperative period after EC-IC bypass and kept improved state during long-term follow-up, although cerebral blood flow did not significantly improved. Therefore, cerebrovascular reserve may be a good indicator of postoperative hemodynamic improvement resulted from bypass effect.

• The Korean Journal of Nuclear Medicine
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• v.23 no.2
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• pp.155-163
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• 1989

Regional cerebral perfusion was evaluated in 15 normal controls by single photon emission computed tomography using $^{99m}Tc$ HM-PAO. For quantitative analysis, 13 pairs of homologous region of interest (ROI) were drawn on three transverse slices matching the vascular territories and cerebral cortices, and normal values of 3 semiqunatitative indices including 'Right to left ratio'(R/L ratio), 'Regional index'(RI), and 'Region to cerebellum ratio'(R/cbll ratio) were calculated. Mean values of R/L ratios of homotogous regions were ranged from 0.985 to 1.023, and mean ${\pm}2$ s.d. of all regions did not exceed 11% of mean. Significant difference of RIs (mean count per voxel of a ROI/mean count per voxel of total ROIs) between regions were found (p<0.001) with highest values in occipital cortex and cerebellum. After attenuation correction, RIs in deep gray, cranial portion of anterior cerebral artery and vascular territories in the 2nd slice increased significantly (p < 0.05-0.001), but vise versa in other ROIs. Region to cerebellum ratios also showed regional difference similar to RIs.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.3
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• pp.192-200
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• 2008

To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Methods: Total fifty six (M:F = 33:24, age $6.7{\pm}3.2$ years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was $33{\pm}21$ months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. Results: In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal lobe of the hemispheres with EDAS and frontal EGS, the post-operative CVRI, and ${\Delta}CVRI$ showed a significant difference between patients with a good and poor clinical outcome (p<0.05). In a multivariate logistic regression analysis, the ${\Delta}CVRI$ and the post-operative CVRI of medial frontal gyrus on the hemispheres where EDAS with frontal EGS was performed were the significant predictive factors for the clinical outcome (p =0.002, p =0.015), Conclusion: With probabilistic map, we could objectively evaluate pre/post-operative hemodynamic changes of pediatric patients with moyamoya disease. Specifically the post-operative CVRI and the post-operative CVRI of medial frontal gyrus where EDAS with frontal EGS was done were the significant predictive factors for further clinical outcomes.