• Investigative Magnetic Resonance Imaging
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• v.11 no.1
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• pp.1-9
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• 2007

The obstacles for cardiac imaging are motion artifacts due to cardiac motion, respiration, and blood flow, and low signal due to small tissue volume of heart. To overcome these obstacles, fast imaging technique with ECG gating is utilized. Cardiac exam using MRI comprises of morphology, ventricular function, myocardial perfusion, metabolism, and coronary artery morphology. During cardiac morphology evaluation, double and triple inversion recovery techniques are used to depict myocardial fluidity and soft tissue structure such as fat tissue, respectively. By checking the first-pass enhancement of myocardium using contrast-enhanced fast gradient echo technique, myocardial blood flow can be evaluated. In addition, delayed imaging in 10 - 15 minutes can inform myocardial destruction such as chronic myocardial infarction. Ventricular function including regional and global wall motion can be checked by fast gradient echo cine imaging in quantitative way. MRI is acknowledged to be practical for integrated cardiac evaluation technique except coronary angiography. Especially delay imaging is the greatest merit of MRI in myocardial viability evaluation.

• Korean Journal of Acupuncture
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• v.23 no.3
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• pp.73-80
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• 2006

목 적 : 씨클로포스파미드(Cyclophosphamide, CP)는 많은 종양 질환에서 단독 혹은 다른 화학요법과 함께 사용되는 항암제이다. CP의 독성과 부작용으로 출혈성 방광염이 많은 문제를 일으키고 있다. CP로 유도된 방광염 모델은 하부요로의 통증질환을 이해하기 위한 내장성 통증의 주요한 모델로 사용되고 있다. 본 연구는 암컷 백서에서 CP로 유도된 방광의 과활동성에 대한 침의 효과를 관찰하기 위해 요류역학검사를 수행하였다. 방 법 : CP (200 mg/kg) 투여 18시간 후에, 지속적 생리식염수 관류 (분당 0.04 ml) 로 방광내압 측정을 통해 방광기능을 평가하였다. 관류 2시간 이후부터, 위중/곤륜 100 Hz, 위중/곤륜 2 Hz, 족삼리/삼음교 100 Hz, 족삼리/삼음교 2Hz 전침 자극을 하여 자침 전후의 방광수축간격(intercontraction interval, ICI)을 비교하였다. 결 과 : 방광내압 측정하는 동안, 방광수축간격은 CP로 유도된 방광염 모델에서 정상군에서 보다 유의하게 짧았다. CP로 유도된 방광염 모델에서, 위중/곤륜 100Hz 전침 자극은 자침 전보다 통계적으로 유의하게 $40.6\;{\pm}\;10.9\;%$ 증가시켰고, 2Hz 전침 자극은 자침 전보다 현저하게 $22.1\;{\pm}\;13.7\;%$ 증가시켰다. 반면에, 족삼리/삼음교 전침 자극은 100Hz, 강 2Hz 전침 자극 각각 $13.7\;{\pm}\;8.1\;%,\;8.7\;{\pm}\;4.5\;%$ 약간 증가시켰다. 결 론 : 족태양방광경의 경혈에 100Hz 전칩 자극을 하여 CP로 유도된 방광의 과활동성을 억제하였다. 이러한 결과는 침 자극으로 CP로 유도된 혹은 다른 종류의 방광염을 치료하는데 효과적일 것임을 시사한다. 또한, 특정 경락의 경혈과 해당 장부의 질환의 치료에 연관성을 보여준다.

• Journal of radiological science and technology
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• v.46 no.1
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• pp.29-36
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• 2023

To have highly reliable diagnostic performance of it, this study comparatively analyzed spatial resolution of SPECT images and interrelationship depending on the changes of system uniformity of ga㎜a camera through phantom analysis. This study chose 6 kinds of results from quality control (uniformity) of triple head SPECT scanner operated in an university hospital in Seoul for six months. Then, study measured spatial resolutions (FWHM) of the images restructured by injecting radiopharmaceuticals to Jaszczak phantom, and doing SPECT scanning under the same conditions as clinical ones using the analytical program (image J). Quality controls performed by the experimental institution showed that differential uniformity of UFOV ranged from 2.76% to 7.61% (4.46±2.07), and integral uniformity of UFOV ranged from 1.98% to 5.42% (3.01±1.43). Meanwhile, Quantitative analysis evaluations of phantom images depending on the changes of uniformity of SPECT scanner detector showed that as the uniformity values of UFOV and CFOV decreased, FWHM values of phantom images decreased from 8.5 ㎜ to 5.8 ㎜. That is, it was quantitatively identified that the higher uniformity of detector is, the better spatial resolution of images gets (P<0.05). It is very important to perform continuous and consistent quality control of the nuclear medicinal system, and users should be clearly conscious of it.

• Journal of radiological science and technology
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• v.32 no.3
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• pp.325-334
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• 2009

Purpose : This study was conducted to assess how effective the permeability ratio and relative cerebral blood volume ratio are to tumor through perfusion MRI by measuring and reflecting the grade assessment and differential diagnosis and the permeability and relative cerebral blood volume of contrast media plunged from blood vessel into organ due to breakdown of blood-brain barrier in cerebral. Subject and Method : Subject of study was 29 patients whose diagnosis were confirmed by biopsy after surgery and 550 (11 slice$\times$50 image) perfusion MRI were used to make image of relative cerebral blood volume with the program furnished on instrument. The other method was to transmit to private computer and the image analysis was made additionally by making image of relative cerebral blood volume-reformulated singular value decomposition, rCBV-rSVD and permeability using IDL.6.2. In addition, Kruskal-wallis test tonggyein non numerical average by a comparative analysis of brain tumors Results : The rCBV ratio (Functool PF; GE Medical Systems and IDL 6.2 program by analysis) and permeability ratio of tumors were as follows; high grade glioma(n=4), (14.75, 19.25) 13.13. low grade astrocytoma(n=5) (14.80, 15.90) 11.60, glioblastoma(n=5) (10.90, 18.60), 22.00, metastasis(n=6) (11.00, 15.08). 22.33. meningioma(n=6) (18.58, 7.67), 5.58. oliogodendroglioma(n=3) (23.33, 16.33, 15.67. Conclusion : It was not easy to classify the grade with the relative cerebral blood volume ratio measured by using the relative cerebral blood image by type of tumors, however, permeability ratio measured by permeability image revealed that the higher the grade of tumor, the higher the measured permeability ratio, showing the assessment of tumor grade is more effective to differential diagnosis.

• Journal of dental hygiene science
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• v.2 no.1
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• pp.47-51
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• 2002

The concentration of intracellular $Ca^{2+}$ was measured by spectrofluorometer after rat submandibular acinar cells were loaded with fura-2/AM(fura-2). After isoproterenol and octanol were administered while letting submandibular gland acinar cell placed in a perfusion chamber flow through a standard solution, the changes of $Ca^{2+}$ concentration were measured. When they were administered separately, there showed little changes of intracellular $Ca^{2+}$ concentration. When they were administered at the same time, however the concentration of intracellar $Ca^{2+}$ was shown to increase. When forskolin, an adenylate cyclase activater, was administerd together with octanol the response looked similar to the response of isoproterenol. In case of the extracellular $Ca^{2+}$ was removed by omitting $Ca^{2+}$ in standard solution and treating EGTA, isoproterenol and forskolin does not affect to the concentration of intracellular $Ca^{2+}$. Therefore, it was certified that the increase of intracellular $Ca^{2+}$ was caused from outside the cell. In order to know that the $Ca^{2+}$ influx is related with capacitative entry pathway, godolinium, blocker of that pathway was treated. With the result of that experiment there was no complete control of the increase in the concentration of intracellular $Ca^{2+}$. However, speed and amount of $Ca^{2+}$ increase was comparatively diminished.

• Korean Journal of Bronchoesophagology
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• v.1 no.1
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• pp.75-81
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• 1995

To evaluate the diagnostic value of pulmonary perfusion scan, we obtained 99mTc MAA per-fusion lung scan from 25 cases of airway foreign bodies. The results were as follows. 1) Significant changes in blood gases were not observed after the establishment of regional hypoperfusion caused by airway foreign body. 2) Near total or total defect was noted on perfusion scan from most of the airway foreign body. 3) There was correspondance of findings of perfusion lung scan and duration of airway foreign body. 4) After the removal of airway foreign bodies, perfusion scan abnormalities were reversed in parallel with the recovery of pulmonary blood flow. We concluded that pulmonary perfusion scan may be valuable for detection of foreign body and reversible hypoperfusion.

• The Korean Journal of Nuclear Medicine
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• v.32 no.6
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• pp.497-508
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• 1998

Purpose: Using rest T1-201/dipyridamole stress gated Tc-99m-MIBI/ 24 hour delay T1-201 SPECT, we investigated the predictive values of the markers of the stress-rest reversibility (Rev), T1-201 rest perfusion (Rest), T1-201 24 hour redistribution (Del) and Tc-99m-MIBI gated systolic thickening (Thk) for wall motion improvement after coronary artery bypass surgery. Materials and Methods: In 39 patients (M;F= 34:5, age $58{\pm}8$), preoperative and postoperative (3 months) SPECT were compared. 24 hour delayed SPECT was done in 16 patients having perfusion defects at rest. Perfusion or wall motion was scored from 0 to 3 (0: normal to 3: defect or dyskinesia). Wall motion was abnormal in 142 segments among 585 segments of 99 artery territories which were surgically revascularized. Results: After bypass surgery, ejection fraction increased from $37.8{\pm}9.0%$ to $45.5{\pm}12.3%$ in 22 patients who had decreased ejection fraction preoperatively. Wall motion improved in 103 (72.5%) segments among 142 dysfunctional segments. Positive predictive values (PPV) of Rev, Rest, Del, and Thk were 83%, 76%, 43%, and 69% respectively. Negative predictive values (NPV) of Rev, Rest, Del, and Thk were 48%, 44%, 58%, and 21%, respectively. Rest/gated stress/delay SPECT had PPV of 74% and NPV of 46%. Though univariate logistic regression analysis revealed Rev (p=0.0008) and Rest (p=0.024) as significant predictors, stepwise multivariate test found Rev as the only good predictor (p=0.0008). Conclusion: Among independent predictors obtained by rest T1-201/ stress gated Tc-99m-MIBI/ delayed T1-201 myocardial SPECT for wall motion improvement after bypass surgery, stress-rest reversibility was the single most useful predictor.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.3
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• pp.214-221
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• 2008

Purpose: We make a qualitative analysis of whether Fusion SPECT/CT can find lesion's anatomical sites better than existing SPECT or not, and we want to show the usefulness of SPECT/CT through finding out effects of CT attenuation correction on SPECT images. Materials and Method: 1. The evaluation of fusion images: This study comprised patients who was tested $^{131}I$-MIBG, Bone, $^{111}In$-Octreotide, Meckel's diverticulum, Parathyroid MIBI with Precedence 16 or Symbia T2 from 2008 Jan to Aug. We compared SPECT/CT image with non fusion image and make a qualitative analysis. 2. The evaluation of attenuation correction: We classified 38 patients who was tested 201Tl myocardial exam with Symbia T2 into 5 sections by using Cedars Sinai' QPS program - Ant, Inf, Lat, Septum, Apex. And we showed each section's perfusion states by percentage. We compared the each section's perfusion-states differences between CT AC and Non AC by average${\pm}$standard deviation. Results: 1. The evaluation of fusion images : In high energy $^{131}I$ cases, it was hard to grasp exact anatomical lesions due to difference between regions and surrounding lesions' uptake level. After combining with CT, we could grabs anatomical lesion more exactly. And in meckel's diverticulum case or to find lesions around bowels or organs with $^{111}In$ cases, it demonstrates its superiority. Bone SPECT/CT images help to distinguish between disk spaces certainly and give correct results. 2. The evaluation of attenuation correction: There is no significant difference statistically in Ant and Lat (p>0.05), but there is a meaningful difference in Inferior, Apex and Septum (p<0.05). AC perfusion at inferior wall in the 5 sections of myocardium: The perfusion difference between Non AC perfusion image ($68.58{\pm}7.55$) and CT corrected perfusion image ($76.84{\pm}6.52$) was the largest by $8.26{\pm}4.95$ (p<0.01, t=10.29). Conclusion: Nuclear medicine physicians can identify not only molecular image which shows functional activity of lesions but also anatomical location information of lesions with more accuracy using the combination of SPECT and CT systems. Of course this combination helps nuclear medicine physician find out the abnormal parts. Moreover combined data sets help separate between normal group and abnormal group in complicated body part. So clinicians can carry out diagnosis and treatment planning at the same time with a single test image. In addition, when we examine a myocardium in thorax where attenuation can occur easily, we can trust perfusion more in a certain region in SPECT test because CT provides the capability for accurate attenuation correction. In these reasons, we think we can prove the justice after treatment fusion image.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.560-567
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• 2002

주산기 뇌손상은 주로 급격한 저산소-허혈 손상에 의하는데 급격한 산소 공급의 차단은 oxidative phosphorylation을 정지 시켜서 뇌대사를 위한 에너지 공급이 차단되게 된다. 에너지 공급이 차단된 뇌세포는 뇌세포막에서 세포 내외의 이온 농도 차를 유지시키던 ATP-dependent $Na^{+}-K^{+}$ pump의 기능이 정지 되고, 세포 내외의 농도 차에 따라 $Na^{+}$, $Cl^{+}$, $Ca^{{+}{+}}$의 대규모 세포 내로 이동이 일어난다. 세포 내로 calcium 이온의 이동은 glutamate 수용체의 활성화에 의해서도 일나는데, 세포 내 calcium 이온의 증가는 protease, lipase, nuclease 등을 활성화 시켜 세포를 사망에 이르게 하는 연속적이고 다양한 생화학적 반응을 일으키게 된다. Glutamate는 대표적인 신경 전달 물질인데 저산소-허혈 손상 시 glutamate 수용체의 지나친 흥분은 미성숙 뇌에 뇌손상을 유발하는데, NMDA 또는 non-NMDA 수용체와 복합체를 형성하고 있는 calcium 이동 통로를 활성화 시켜 세포 내 calcium 이온을 증가시키고, 그 외에 metabotropic recetor는 G-protein의 활성화 등을 통해 뇌손상을 유발하는 다양한 생화학적 반응을 매개한다. 저산소-허혈 손상 후 재산소화와 재관류가 일어나면서 뇌세포의 지연성 사망(secondary neuronal death)이 일어나는데 이는 초기 손상 후 뒤이어 일어나는 다양한 생화학적 반응에 의하는데 다량의 산소 자유기 발생, nitric oxide의 생성, 염증 반응과 싸이토카인, 신경전도 물질의 과흥분 등이 관여하며, 신경 세포 사망은 세포괴사(necrosis)뿐 아니라 일부는 세포 사멸(apoptosis)로 알려진 의도된 세포 사망(programmed cell death)에 의한 것으로 생각되고 있다(Fig. 2).

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.317-325
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• 2006

Purpose : This study was carried out to elucidate the effects of nitric oxide synthase(NOS) inhibitor, NG-monomethyl-L-arginine(L-NMMA) and nitric oxide precursor, L-arginine(L-Arg) on cerebral hemodynamics and energy metabolism during reoxygenation-reperfusion(RR) after hypoxia-ischemia(HI) in newborn piglets. Methods : Twenty-eight newborn piglets were divided into 4 groups; Sham normal control(NC), experimental control(EC), L-NMMA(HI & RR with L-NMMA), and L-Arg(HI & RR with L-Arg) groups. HI was induced by occlusion of bilateral common carotid arteries and simultaneously breathing with 8 percent oxygen for 30 mins, and followed RR by release of carotid occlusion and normoxic ventilation for one hour. All groups were monitored with cerebral hemodynamics and cytochrome $aa_3$ (Cyt $aa_3$) using near infrared spectroscopy(NIRS). $Na^+$, $K^+$-ATPase activity, lipid peroxidation products, and tissue high energy phosphate levels were determined biochemically in the cerebral cortex. Results : In experimental groups, mean arterial blood pressure, $PaO_2$, and pH decreased, and base excess and blood lactate level increased after HI compared to NC group(P<0.05). These variables subsequently returned to baseline after RR except pH. There were no differences among the experimental groups. In NIRS, oxidized hemoglobin($HbO_2$) decreased and hemoglobin(Hb) increased during HI(P<0.05) but returned to base line immediately after RR; 40 min after RR, the $HbO_2$ had decreased significantly compared to NC group(P<0.05). Changes of Cyt $aa_3$ decreased significantly compared to NC after HI and recovered at the end of the experiment. Significantly reduced cerebral cortical cell membrane $Na^+$, $K^+$-ATPase activity and increased lipid peroxidation products(P<0.05) were not improved with L-NMMA or L-Arg. Conclusion : These findings suggest that NO is not involved in the mechanism of HI and RR brain damage during the early acute phase of RR.