• Investigative Magnetic Resonance Imaging
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• v.15 no.2
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• pp.91-101
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• 2011

Perfusion magnetic resonance imaging (pMRI) is a special technique for evaluation of blood flow. Exogenous pMRI methods which are dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) use an intravenous bolus injection of paramagnetic contrast agent. In contrast, an endogenous pMRM method which is arterial spin labeling (ASL) use diffusible blood in body. In order to scan pMRI in human, technical optimizations are very important according to disease conditions. For examples, DSC is popularly used in patients with acute stroke due to its short scan time, while DSC or DCE provides the various perfusion indices for patients with tumor. ASL is useful for children, women who are expected to be pregnant, and in patients with kidney diseases which are problematic in nephrogenic systemic fibrosis (NSF). Perfusion MRI does not require any injection of radioisotopes. We expect that demand for perfusion MRI will be higher in evaluating drug efficacy and other treatment effects.

• Annals of Clinical Neurophysiology
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• v.25 no.2
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• pp.93-102
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• 2023

Background: We aimed to identify any differences in the structural covariance network based on structural volume and those in the functional network based on cerebral blood flow between the ipsilateral and contralateral hemispheres of pain in patients with episodic migraine without aura. Methods: We prospectively enrolled 27 patients with migraine without aura, all of whom had unilateral migraine pain. We defined the ipsilateral hemisphere as the side of migraine pain. We measured structural volumes on three-dimensional T1-weighted images and cerebral blood flow using arterial spin labeling magnetic resonance imaging. We then analyzed the structural covariance network based on structural volume and the functional network based on cerebral blood flow using graph theory. Results: There were no significant differences in structural volume or cerebral blood flow between the ipsilateral and contralateral hemispheres. However, there were significant differences between the hemispheres in the structural covariance network and the functional network. In the structural covariance network, the betweenness centrality of the thalamus was lower in the ipsilateral hemisphere than in the contralateral hemisphere. In the functional network, the betweenness centrality of the anterior cingulate and paracingulate gyrus was lower in the ipsilateral hemisphere than in the contralateral hemisphere, while that of the opercular part of the inferior frontal gyrus was higher in the former hemisphere. Conclusions: The present findings indicate that there are significant differences in the structural covariance network and the functional network between the ipsilateral and contralateral hemispheres of pain in patients with episodic migraine without aura.

• The Journal of Korean Medicine
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• v.44 no.4
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• pp.104-120
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• 2023

Objectives: The purpose of this study was to explore the therapeutic mechanism of acupuncture and bee venom acupuncture (BVA) in patients with idiopathic Parkinson's disease (IPD) using positron emission tomography (PET) and arterial spin labeling (ASL). Methods: Patients with IPD who received a stable dose of anti-parkinsonian medication for at least 4 weeks were recruited and randomly divided into one of two groups: treatment and control. The treatment group (11 subjects) received acupuncture and BVA at acupoints, and the control group (9 subjects) received sham acupuncture and normal saline injections at non-acupoints, twice per week for 12 weeks. The patients were examined using PET and ASL at baseline and after the 12-week treatment. In addition, age- and sex-matched healthy subjects without neurological symptoms and history were recruited to compare ASL data of patients with IPD. Results: PET results revealed that striatal dopamine transporter binding increased in each group after 12 weeks. Although the change was larger in the treatment group, the difference was not statistically significant. In ASL results, the treatment group exhibited hyperperfusion in specific regions compared with the healthy control group. After 12 weeks' intervention, hyperperfusion regions were recovered only in the treatment group. In contrast, significant changes were not found in hyperperfusion regions in the control group after 12 weeks. Conclusions: Our findings suggest that the therapeutic mechanisms of acupuncture and BVA in IPD are different from placebo and operate by altering dopamine availability and recovering hyperactivity in cerebral blood flow.