• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.5
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• pp.1016-1026
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• 2017

Shipping Along with the aging of the total population, its importance is greater cause of stroke, which is one of the diseases are listed cerebral perfusion is about 80%,.ie that the flow of blood flowing to the brain is reduced as the cause. One of the most typical prophylaxis and treatment of these stroke is to enhance cerebral perfusion. There are several ways to increase cerebral blood flow are a therapy through drugs, through surgery and invasive NeuroFlo. NeuroFlo is to insert a catheter to which a balloon is attached into a patient's artery. However, since the method of enhancing conventional cerebral perfusion have been conducted mainly in invasive method, giving a burden to the patient, the problem of inducing a number of complications were noted. In this paper, an attempt to supplement the shortcomings of such invasive brain perfusion increase method, to provide a device to enhance the non-invasively brain perfusion.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.2
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• pp.85-90
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• 2007

Acute event in cerebrovascular disease is the second most common cause of death in Korea following cancer, and it can also cause serious neurologic deficits. Understanding of perfusion status is important for clinical applications in management of patients with cerebrovascular diseases, and then the attacks of ischemic neurologic symptoms and the risk of acute events can be reduced. Therefore, the normal vascular anatomy of brain, various clinical applications of acetazolamide-enhanced brain perfusion SPECT, including meaning and role of assessment of vascular reserve in carotid stenosis before procedure, in pediatric Moyamoya disease before and after operation, in prediction of development of hyperperfusion syndrome before procedure, and in prediction of vasospasm and of prognosis in subarachnoid hemorrahge were reviewed in this paper.

• Dementia and Neurocognitive Disorders
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• v.16 no.3
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• pp.72-77
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• 2017

Background and Purpose Although sleep disturbances are common and considered a major burden for patients with Alzheimer's disease (AD), the fundamental mechanisms underlying the development and maintenance of sleep disturbance in AD patients have yet to be elucidated. The aim of this study was to examine the correlation between regional cerebral blood flow (rCBF) and sleep disturbance in AD patients using technetium-99m hexamethylpropylene amine oxime single-photon emission computed tomography (SPECT). Methods A total of 140 AD patients were included in this cross-sectional study. Seventy patients were assigned to the AD with sleep loss (SL) group and the rest were assigned to the AD without SL group. SL was measured using the sleep subscale of the Neuropsychiatric Inventory. A whole-brain voxel-wise analysis of brain SPECT data was conducted to compare the rCBF between the two groups. Results The two groups did not differ in demographic characteristics, severity of dementia, general cognitive function, and neuropsychiatric symptoms, with the exception of sleep disturbances. The SPECT imaging analysis displayed decreased perfusion in the bilateral inferior frontal gyrus, bilateral temporal pole, and right precentral gyrus in the AD patients with SL group compared with the AD patients without SL group. It also revealed increased perfusion in the right precuneus, right occipital pole, and left middle occipital gyrus in the AD with SL group compared with the AD without SL group. Conclusions The AD patients who experienced sleep disturbance had notably decreased perfusion in the frontal and temporal lobes and increased rCBF in the parietal and occipital regions. The findings of this study suggest that functional alterations in these brain areas may be the underlying neural correlates of sleep disturbance in AD patients.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.25-31
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• 2007

Background: Cerebral protection is one of the most important procedures during aortic arch surgery. We can minimize neurological complications through short period of total circulatory arrest and resuming of brain perfusion. We evaluated 11 patients who underwent arch replacement using antegrade brain perfusion via right axillary artery. Material and Method: Between July 2004 and July 2006, 11 patients (male 9, female 2) underwent aortic arch replacement with antegrade brain perfusion via right axillary artery. Preoperative diagnosis was listed; 5 type A aortic dissections (5/11, 45.5%), 5 aortic aneurysms (5/11, 45,5%) and 1 type A IMH (intramural hematoma, 1/11, 9%). The mean age at the time of operation was $60.3{\pm}12.8$ years. For antegrade brain perfusion, we performed right axillary artery cannulation in all patients. Retrograde brain perfusion was used briefly during total circulatory arrest. Result: The mean total circulatory arrest time was $31.1{\pm}16.9$ minutes and the mean retrograde brain perfusion time was $21{\pm}17.8$ minutes. Mean antegrade brain perfusion time was $77.9{\pm}17.5\;(43{\sim}101)$ minutes. We had neither operative mortality nor permanent neurological complications. Conclusion: By means of antegrade brain perfusion via right axillary artery, that could lead to decrease circulatory arrest time and minimize damages to severely atheromatous arch vessels, we can expect to reduce neurological complications after aortic arch replacement. Further investigation with iarge patient populations will be required.

• Journal of Biomedical Engineering Research
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• v.17 no.4
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• pp.443-448
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• 1996

Sequential brain SPECT imaging has been used to assess the cerebral perfusion reserve(CPR) in cerebrovascular diseases(UD). We have realized parametric images of CPR using deadtime correction of gamma camera and normalized difference ratio. For the anatomical localization of CPR, the parametric images were registered to the contours of the cerebral regions using optimal threshold method, which showed to reflect the CPR more reliably and distinctively than the simple subtraction. We conclude that the quantitative estimation of CPR using normalized difference ratio image could be useflll for the diagnosis and prognostic assessment of CVD.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1575-1578
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• 2012

Objectives: To obtain permeability surface (PS) values using multi-slice helical CT perfusion imaging and to evaluate the spatial distribution correlation between PS values and vascular endothelial growth factor (VEGF) expression in solitary brain metastases. Methods: Imaging was performed on 21 patients, PS values being calculated from the central, border and peripheral parts of tumours. VEGF expression was determined by immunohistochemical staining. Results: Rim enhancement was found in 16 cases, the border of the tumour featuring PS elevation with high VEGF expression in 13 cases. In the 5 cases with nodular enhancement, the border and the central part had high permeability and VEGF expression was high in all cases, the correlation being significant (P<0.01). Conclusion: VEGF expression in brain metastases positively correlates with PS values from CT perfusion imaging, so that the latter can be used in the surveillance of angiogenic activity in brain metastases.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.119-124
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• 1997

Purpose: To assess the utility of magnetic resonance(MR) cerebral blood volume (CBV) map in the evaluation of brain tumors. Materials and Methods: We performed perfusion MR imaing preoperatively in the consecutive IS patients with intracranial masses(3 meningiomas, 2 glioblastoma multiformes, 3 low grade gliomas, 1 lymphoma, 1 germinoma, 1 neurocytoma, 1 metastasis, 2 abscesses, 1 radionecrosis). The average age of the patients was 42 years (22yr -68yr), composed of 10 males and S females. All MR images were obtained at l.ST imager(Signa, CE Medical Systems, Milwaukee, Wisconsin). The regional CBV map was obtained on the theoretical basis of susceptibility difference induced by first pass circulation of contrast media. (contrast media: IScc of gadopentate dimeglumine, about 2ml/sec by hand, starting at 10 second after first baseline scan). For each patient, a total of 480 images (6 slices, 80 images/slice in 160 sec) were obtained by using gradient echo(CE) single shot echo-planar image(EPI) sequence (TR 2000ms, TE SOms, flip angle $90^{\circ}$, FOV $240{\times}240mm,{\;}matrix{\;}128{\times}128$, slice-thick/gap S/2.S). After data collection, the raw data were transferred to CE workstation and rCBV maps were generated from the numerical integration of ${\Delta}R2^{*} on a voxel by voxel basis, with home made software (${\Delta}R2^{*}=-ln (S/SO)/TE). For easy visual interpretation, relative RCB color coding with reference to the normal white matter was applied and color rCBV maps were obtained. The findings of perfusion MR image were retrospectively correlated with Cd-enhanced images with focus on the degree and extent of perfusion and contrast enhancement. Results: Two cases of glioblastoma multiforme with rim enhancement on Cd-enhanced Tl weighted image showed increased perfusion in the peripheral rim and decreased perfusion in the central necrosis portion. The low grade gliomas appeared as a low perfusion area with poorly defined margin. In 2 cases of brain abscess, the degree of perfusion was similar to that of the normal white matter in the peripheral enhancing rim and was low in the central portion. All meningiomas showed diffuse homogeneous increased perfusion of moderate or high degree. One each of lymphoma and germinoma showed homogenously decreased perfusion with well defined margin. The central neurocytoma showed multifocal increased perfusion areas of moderate or high degree. A few nodules of the multiple metastasis showed increased perfusion of moderate degree. One radionecrosis revealed multiple foci of increased perfusion within the area of decreased perfusion. Conclusion: The rCBV map appears to correlate well with the perfusion state of brain tumor, and may be helpful in discrimination between low grade and high grade gliomas. The further study is needed to clarify the role of perfusion MR image in the evaluation of brain tumor.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.56-64
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• 1996

The purpose of this study was to evaluate the characteristic perfusion changes in patients with Sturge-Weber syndrome by comparison of the findings of brain MR images and perfusion SPECT images. $^{99m}Tc$-HMPAO or $^{99m}Tc$-ECD interictal brain SPECTs were performed on 5 pediatric patients with Sturge-Weber syndrome within 2 weeks after MR imaging. Brain SPECTs of three patients without calcification showed diminished perfusion in the affected area on MR image. A 3 month-old patient without brain atrophy or calcification demonstrated paradoxical hyperperfusion in the affected hemisphere, and follow-up perfusion SPECT revealed decreased perfusion in the same area. The other patient with advanced calcified lesion and atrophy on MR image showed diffusely decreased perfusion in the affected hemisphere, but a focal area of increased perfusion was also noted in the ipsilateral temporal lobe on SPECT. In conclusion, brain perfusion of the affected area of Sturge-Weber syndrome patients was usually diminished, but early or advanced patients may show paradoxical diffuse or focal hyperperfusion in the affected hemisphere. Further studies are needed for better understanding of these perfusion changes and pathophysiology of Sturge-Weber syndrome.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.165-172
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• 2012

We investigated the vascular characteristics of tumors and normal tissue using perfusion CT in the rabbit brain tumor model. The VX2 carcinoma concentration of $1{\times}10^7$ cells/ml(0.1ml) was implanted in the brain of nine New Zealand white rabbits (weight: 2.4kg-3.0kg, mean: 2.6kg). The perfusion CT was scanned when the tumors were grown up to 5mm. The tumor volume and perfusion value were quantitatively analyzed by using commercial workstation (advantage windows workstation, AW, version 4.2, GE, USA). The mean volume of implanted tumors was $316{\pm}181mm^3$, and the biggest and smallest volumes of tumor were 497 $mm^3$ and 195 $mm^3$, respectively. All the implanted tumors in rabbits are single-nodular tumors, and intracranial metastasis was not observed. In the perfusion CT, cerebral blood volume (CBV) were $74.40{\pm}9.63$, $16.08{\pm}0.64$, $15.24{\pm}3.23$ ml/100g in the tumor core, ipsilateral normal brain, and contralateral normal brain, respectively ($p{\leqq}0.05$). In the cerebral blood flow (CBF), there were significant differences between the tumor core and both normal brains ($p{\leqq}0.05$), but no significant differences between ipsilateral and contralateral normal brains ($962.91{\pm}75.96$ vs. $357.82{\pm}12.82$ vs. $323.19{\pm}83.24$ ml/100g/min). In the mean transit time (MTT), there were significant differences between the tumor core and both normal brains ($p{\leqq}0.05$), but no significant differences between ipsilateral and contralateral normal brains ($4.37{\pm}0.19$ vs. $3.02{\pm}0.41$ vs. $2.86{\pm}0.22$ sec). In the permeability surface (PS), there were significant differences among the tumor core, ipsilateral and contralateral normal brains ($47.23{\pm}25.45$ vs. $14.54{\pm}1.60$ vs. $6.81{\pm}4.20$ ml/100g/min)($p{\leqq}0.05$). In the time to peak (TTP) were no significant differences among the tumor core, ipsilateral and contralateral normal brains. In the positive enhancement integral (PEI), there were significant differences among the tumor core, ipsilateral and contralateral brains ($61.56{\pm}16.07$ vs. $12.58{\pm}2.61$ vs. $8.26{\pm}5.55$ ml/100g). ($p{\leqq}0.05$). In the maximum slope of increase (MSI), there were significant differences between the tumor core and both normal brain($p{\leqq}0.05$), but no significant differences between ipsilateral and contralateral normal brains ($13.18{\pm}2.81$ vs. $6.99{\pm}1.73$ vs. $6.41{\pm}1.39$ HU/sec). Additionally, in the maximum slope of decrease (MSD), there were significant differences between the tumor core and contralateral normal brain($p{\leqq}0.05$), but no significant differences between the tumor core and ipsilateral normal brain($4.02{\pm}1.37$ vs. $4.66{\pm}0.83$ vs. $6.47{\pm}1.53$ HU/sec). In conclusion, the VX2 tumors were implanted in the rabbit brain successfully, and stereotactic inoculation method make single-nodular type of tumor that was no metastasis in intracranial, suitable for comparative study between tumors and normal tissues. Therefore, perfusion CT would be a useful diagnostic tool capable of reflecting the vascularity of the tumors.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1194-1202
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• 2021

Objective: To investigate the age-dependent changes in regional cerebral blood flow (CBF) in healthy adults by fitting mathematical models to imaging data. Materials and Methods: In this prospective study, 90 healthy adults underwent pseudo-continuous arterial spin labeling imaging of the brain. Regional CBF values were extracted from the arterial spin labeling images of each subject. Multivariable regression with the Akaike information criterion, link test, and F test (Ramsey's regression equation specification error test) was performed for 7 models in every brain region to determine the best mathematical model for fitting the relationship between CBF and age. Results: Of all 87 brain regions, 68 brain regions were best fitted by cubic models, 9 brain regions were best fitted by quadratic models, and 10 brain regions were best fitted by linear models. In most brain regions (global gray matter and the other 65 brain regions), CBF decreased nonlinearly with aging, and the rate of CBF reduction decreased with aging, gradually approaching 0 after approximately 60. CBF in some regions of the frontal, parietal, and occipital lobes increased nonlinearly with aging before age 30, approximately, and decreased nonlinearly with aging for the rest of life. Conclusion: In adults, the age-related perfusion patterns in most brain regions were best fitted by the cubic models, and age-dependent CBF changes were nonlinear.