• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.437-442
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• 2001

For ischemic cerebrovascular disease, it is well known that early luxury perfusion is related to a good clinical outcome and single photon emission computed tomography(SPECT) has the potential for providing useful information about regional cerebral blood flow. We report one case of Rt. MCA infarction mainly treated by oriental medicine and revealed luxury perfusion without thrombolysis. In acute stage, neurological deficits of the patient were very severe. 99mTc-HMPAO SPECT images obtained 10days after the attack showed large perfusion defect in the Rt. MCA territory. We followed up 99mTc-HMPAO SPECT 40days after the ictus. Despite of the poor early perfusion, we found considerably improved perfusion and neurological improvement.

• The Korean Journal of Nuclear Medicine
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• v.22 no.1
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• pp.15-19
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• 1988

SPECT of regional cerebral blood flow was performed using $^{99m}Tc-HMPAO$ in 28 patients with cerebrovascular disease and quantitative analysis was done. Cerebral asymmetry index and percent index of asymmetry of cerebellar hemisphere of patients with cerebral infarction or ischemia were $0.764{\pm}0.576$ and $-5.6{\pm}7.1%$ and those of intracranial hemorrhage was $0.416{\pm}0.251$ and $-2.5{\pm}4.1%$ respectively. According to PIA of cerebellar hemisphere, 12 patients showed crossed cerebellar diaschisis. $^{99m}Tc-HMPAO$ SPECT seemed to be a useful tool for the evaluation of regional cerebral blood flow.

• The Korean Journal of Nuclear Medicine
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• v.23 no.1
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• pp.85-87
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• 1989

Herpes simplex encephalitis (HSE) is one of the fulminant necrotizing, often fatal sporadic form of the encephalitis caused by herpes simplex type I virus. Characteristically, there is early and almost constant involvement of one or both temporal lobes, although there are common additional areas of involvement. Appropriate early treatment following correct diagnosis by clinical findings, CSF study, EEG and several radiological studies including angiography, redionuclide studies, CT or MRI can reduce its mortality and severity of the sequelae. We report a case of HSE diagnosed by adjuvant study of $^{99m}Tc-HMPAO$ regional cerebral blood flow SPECT, which showed a marked increase in bitemporal cerebral blood flow in a 24-year-old man.

• The Korean Journal of Nuclear Medicine
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• v.27 no.2
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• pp.170-174
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• 1993

The quantitative methods for the assessment of the cerebral blood flow using $^{99m}Tc$-HMPAO brain SPECT utilize the measured count distribution in some specific reconstructed tomographic slice or in algebraic summation of a few neighboring slices, rather than the true volumetric distribution, to estimate the relative regional cerebral blood flow, and consequently produce the biased estimates of the true regional cerebral blood flow. This kind of biases are thought to originate mainly from the arbitrarily irregular shape of the cerebral region of interest(ROI) which are analyzed. In this study, a semi-automated method for the direct quantification of the volumetric regional cerebral blood flow estimate is proposed, and the results are compared to those calculated by the previous planar approaches. Bias factors due to the partial volume effect and the uncertainty in ROI determination are not considered presently for the methodological comparison of planar/volumetric assessment protocol.

• Journal of Korean Neurosurgical Society
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• v.40 no.6
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• pp.434-440
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• 2006

Objective : The purpose of this study is to examine the influence of cranioplasty on dynamics of cerebral blood flow[CBF] and cerebrovascular reserve capacity[CVRC], and to investigate the usefulness of single photon emission computed tomography [SPECT] as a prognostic factor for neurological improvement after cranioplasty. Methods : Between March 2003 and December 2005, a prospective study was performed on 24 patients who had undergone total 25 cranioplasty operations. Cerebral blood flow velocities in the middle cerebral artery[MCA] and internal carotid artery[ICA] were obtained by transcranial Doppler ultrasonography[TCD]. The CVRC was assessed by SPECT in the natural state and after stimulation with 1g of acetazolamide. Neurological improvement after cranioplasty was compared between patients who showed hyperactivity to acetazolamide-activated SPECT [Group 1, n=7] and hypoactivity to acetazolamide-activated SPECT [Group 2, n=17]. These measurements were obtained two weeks prior to and two weeks after cranioplasty. Results : The blood flow velocities at the opposite site to the cranioplasty as well as at the cranioplasty site were significantly increased [P<0.05]. Compared with Group 2, there was significant increase in CBF and neurological improvement after cranioplasty in Group 1. Conclusion : Among patients with surgical bony defects, the patients who had normal reactivity of the CVRC showed a significant increase in CBF and neurological improvement after cranioplasty. The authors suggest that CVRC measurement prior to surgery may be an important prognostic factor for neurological improvement after cranioplasty.

• 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.36 no.6
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• pp.357-367
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• 2002

Purpose: While cerebral blood flow and cerebrovascular reserve could be evaluated with basal/acetazolamide Tc-99m-HMPAO SPECT in cerebrovascular disease, objective quantification is necessary to assess the efficacy of the revascularization. In this study we adopted the SPM method to quantify basal cerebral blood flow and cerebrovascular reserve on basal/acetazolamide SPECT in assessment of the patients who underwent bypass surgery for linternal carotid artery (ICA) stenosis. Materials and Methods: Twelve patients ($51{\pm}15$ years) with ICA stenosis were enrolled. Tc-99m-HMPAO basal/acetazolamide perfusion SPECT was peformed before and after bypass surgery. After spatia1 and count normalization to cerebellum, basal cerebral blood flow and cerebrovascular reserve were compared with 21 age-matched normal controls and postoperative changes of regional blood flow and reserve were assessed by Statistical Parametric Mapping method. Mean pixel values of each brain region were calculated using probabilistic anatomical map of lobes. Perfusion reserve was defined as the % changes after acetazolamide over basal counts. Results: Preoperative cerebral blood flow and cerebrovascular reserve were significantly decreased in involved ICA territory, comparing with normal control (p<0.05). Postoperative improvement of cerebral blood flow and cerebrovascular reserve was observed in grafted ICA territories, but cerebrovasculr reserve remained with significant difference with normal control. Improvement of the cerebrovascular reserve was most prominent in the superior temporal and the angular gyrus, nearest to the anastomosis sites. Conclusion: Using SPM quantification method on hasal/acetazolamide Tc-99m-HMPAO SPECT, the cerebral blood flow and cerebrovascular reserve could be assessed before revascularization and so could the efficacy of the bypass surgery.

• The Korean Journal of Nuclear Medicine
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• v.23 no.2
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• pp.149-154
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• 1989

Transient ischemic attacks (TIAs) is a syndrome resulting from brain ischemia lasting less than 24 hours. The mechanisms of TIAs may be similar to those of cerebral embolism and thrombosis, and thus TIAs may be followed by cerebral infarction. Despite the availability of CT scanning, the diagnosis and management of TIAs continue to be difficult. Recently SPECT has been advocated as a diagnostic imaging modality. We performed Tc-99m-HMPAO regional cerebral blood flow (rCBF) SPECT in 24 patients with the clinical diagnosis of TIAs to assess its ability to detect early changes of rCBF, and determine the diagnostic value. Ten men and fourteen women with an average of 51 years (range; 27-74 years) were included. All but 8 patients had normal brain CT prior to SPECT. The two patients had moderate degree of brain atrophy and the 6 patients nonspecific calcifications. Eighteen of the 24 patients had abnormal Tc-99m-HMPAO rCBF SPECT. Fifteen had unilateral involvement and the other three had bilateral involvements. Seventy-five percents of the defects were found in the left cerebral hemisphere. According to the distribution of the lesions (total number: 34 lesions), fourteen were in the parietal, eight in the temporal, and the remainders were elsewhere. Tc-99m-HMPAO rCBF SPECT is sensitive in detecting rCBF abnormalities in patients with TIAs, and represent the most accurate diagnostic tool available in the diagnosis of TIAs.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.27-31
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• 2010

The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.247-259
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• 2000

Objective : The mechanism of acupuncture to increase cerebral blood flow is still uncertain. The purpose of this study was to evaluate the neural basis of acupuncture by comparing the cerebral regions activated by the stimulation of two different methods of acupunctures at the same acupoint which was suggested by oriental medicine to increase rCBF. Materials and Methods : Thirty-nine healthy volunteers(26 males, 13 females, age $31{\pm}11$ years) were studies by rest/acupuncture Tc-99m ECD brain SPECT using a subtraction method. SPECTs using two methods(needle retention and heated needle with 90% alcohol) at two acupoints (right LI. 4 and ST. 36) were peformed at an interval of three days. For the needle retention method, acupuncture needle was inserted to a depth of about 2 cm into each acupoint 8 minutes after the lst acquisition and continued to retain, and the second injection of Tc-99m ECD was done 15 minutes after the insertion of needle. For the heated acupuncture method, heated needle was inserted in a twinkle within several msec 20 second after the second injection of Tc-99m ECD. The differences of between rest and acupuncture activation state were statistically analyzed using a statistical parametric mapping software. Result : Acupunctures of both methods reveal similar patterns of increase in rCBF. Acupuncture at ST.36 increase rGBF in left anterior temporal, right inferior frontal lobes, and left cerebellum. Acupuncture at LI. 4 increase rCBF in the left frontal cortex, right temporal pole, both inferior frontal cortices and right cerebellum. Conclusion : The effects of two different acupunctures to the same acupoints on rCBF were similar. Therefore, this result suggests Chat the mechanism of acupuncture in the increase of cerebral blood flow have a neural basis.