• 한국전산구조공학회논문집
• /
• 제33권3호
• /
• pp.179-186
• /
• 2020

본 연구에서는 복부대동맥류가 발생한 환자들에서의 연령과 복부대동맥류 형상에 따른 벽 응력과 파열 위험성을 평가하였다. 복부대동맥류의 형상은 의료영상 데이터로부터 추출되어 모사되었으며, 재료 물성치 단계에서는 동맥 조직의 이방성 초탄성 성질을 모사하기 위해 Gasser-Ogden-Holzapfel 모델을 적용하였다. 또한, 모델에서 필요한 각 재료 정수들은 환자들의 연령과 정상 조직 및 동맥류 조직의 특성들을 고려하기 위하여 각기 다른 값들로 산정되었다. 게다가 복부대동맥류에서의 대동맥 직경과 목의 각도에 관한 상관관계를 분석하고, 이에 대한 시리즈 시뮬레이션 역시 수행되었다. 그 결과, 복부대동맥류 환자의 연령과 대동맥 직경, 그리고 대동맥 목의 각도에 따른 복부대동맥류의 파열 위험성이 평가되었다.

• Investigative Magnetic Resonance Imaging
• /
• 제22권1호
• /
• pp.26-36
• /
• 2018

Purpose: Children born with single ventricle physiology demonstrate poor growth rate and suffer from malnutrition, which lead to increased morbidity and mortality in this population. We assume that an anabolic steroid, oxandrolone, will promote growth in these infants by improving myocardial energy utilization. The purpose of this paper is to study the efficacy of oxandrolone on myocardial energy consumption in these infants. Materials and Methods: We modeled single ventricle physiology in a lamb by prenatally shunting the aorta to the pulmonary artery and then postnatally, we monitored cardiac energy utilization by quantitatively measuring the first order reaction rate constant, $k_f$ of the creatine-kinase reaction in the heart using magnetization transfer $^{31}P$ magnetic resonance spectroscopy, home built $^1H/^{31}P$ transmit/receive double tuned coil, and transmit/receive switch. We also performed cine MRI to study the structure and dynamic function of the myocardium and the left ventricular chamber. The spectroscopy data were processed using home-developed python software, while cine data were analyzed using Argus software. Results: We quantitatively measured both the first order reaction rate constant and ejection fraction in the control, shunted, and the oxandrolone-treated lambs. Both $k_f$ and ejection fraction were found to be more significantly reduced in the shunted lambs compared to the control lambs, and they are increased in oxandrolone-treated lambs. Conclusion: Some improvement was observed in both the first order reaction rate constant and ejection fraction for the lamb treated with oxandrolone in our preliminary study.

• 대한한의진단학회지
• /
• 제11권1호
• /
• pp.48-60
• /
• 2007

Palpation of the pulse has been used in Korean traditional medicine since ancient times to assess physical health. Pulse wave contour may be obtained by measuring arterial pressure or blood volume change of skin. The latter is called as Photoplethysmography(PPG) or digital volume pulse(DVP). The PPG signal is measured by a device comprising an infrared light sourece and a photodetector. Although less widely used, this technique deserves further consideration because of its simplicity and ease of use. The contour of the PPG is formed as a result of a complex interaction between the left ventricle and the systemic circulation. It usually exhibits an early systolic peak and an early diastolic peak. the first peak is formed mainly by pressure trasmitted along a direct path from the left ventricle to the finger. The second peak is formed in part by pressure transmitted along the aorta and large arteries to sites of impedance mismatch in the lower body. The contour of the PPG is sensitive to changes in arterial tone and is influenced by ageing and large artery stiffness. Measurements taken directly from the PPG or from its second derivative can be used to assess these properties. In some mathematical approaches, the extraction of periodic components using frequency analysis was tried to analysis of the PPG. But we don't understand yet what kind of factor in the cardiovascular system or human body is related with the respective specific Fourier components of PPG. This review describes the background to measurement principles, representative contour, contour analysis and frequency domain analysis of PPG, and current and future.

• Neonatal Medicine
• /
• 제18권2호
• /
• pp.404-408
• /
• 2011

Scimitar증후군은 우측 폐정맥이 하대정맥을 통하여 좌심방이 아닌 우심방으로 연결되는 부분 폐 정맥 환류이상을 보이면서 우측 폐의 발육부전, 우폐동맥의 발육부전 및 폐 분리증 등과 같은 동반 기형을 보이는 매우 드문 심폐기형 가운데 하나이다. 또한 선천성 항문 막힘증은 출생 후 조기에 잘록 창자 창냄술과 같은 적극적인 수술적 치료가 요구되는 항문 직장 기형의 하나로 비뇨기계 이상, 척추 이상, 기관지 식도루, 식도 폐쇄증 혹은 심혈관계 이상 등이 동반될 수 있다. 그러나, 부분 폐 정맥 환류 이상의 하나인 scimitar증후군이 항문 막힘증과 함께 동반됨을 보고한 예는 아직까지 국내외적으로 없었다. 이에 저자들은 호흡 곤란 및 선천성 편측 폐 발육부전 및 항문 막힘증을 주소로 입원한 신생아에서 진단된 scimitar 증후군 1례를 경험하였기에 보고하는 바이다.

• Journal of Chest Surgery
• /
• 제37권9호
• /
• pp.796-799
• /
• 2004

환아는 대동맥 축착을 동반한 Taussig-Bing기형으로 벽속 주행(intramural course)이 의심되는 관상동맥, 대혈관 크기의 현저한 차이, 호전되지 않는 폐렴과 심부전, 잠재적 대동맥하 협착으로 생후 52일에 대동맥궁 재건을 포함한 고식적 Damus-Kaye-Stansel (DKS) 술식을 시행받았다. 생후 45개월에 시행된 완전 교정술은 좌심실에서 폐동맥(신대동맥)으로의 심실중격결손을 폐쇄하고 DKS 술식해체 후관상동맥 전이를 통한 동맥전환술에서 자가 신폐동맥의 판막 기능을 유지한 채 우심실 유출로를 재건하였다. 완전 교정술 후 19개월째 외래 관찰 중으로 심장약은 복용하지 않으며 심초음파 검사에서 특이 소견은 관찰되지 않고 있다. 저자들은 DKS 술식을 받은 Taussig-Bing 기형 환자에서 인조 판막도관의 삽입이 필요한 Rastelli 술식을 피하고 DKS 술식해체과 동맥전환술로 양대혈관 판막을 모두 보존하는 완전 교정술을 시행하여 좋은 성적을 보였기에 보고하는 바이다.

• Journal of Chest Surgery
• /
• 제48권2호
• /
• pp.99-104
• /
• 2015

Background: We report our initial experiences of robot-assisted cardiac surgery using the da Vinci Surgical System. Methods: Between February 2010 and March 2014, 50 consecutive patients underwent minimally invasive robot-assisted cardiac surgery. Results: Robot-assisted cardiac surgery was employed in two cases of minimally invasive direct coronary artery bypass, 17 cases of mitral valve repair, 10 cases of cardiac myxoma removal, 20 cases of atrial septal defect repair, and one isolated CryoMaze procedure. Average cardiopulmonary bypass time and average aorta cross-clamping time were $194.8{\pm}48.6$ minutes and $126.1{\pm}22.6$ minutes in mitral valve repair operations and $132.0{\pm}32.0$ minutes and $76.1{\pm}23.1$ minutes in myxoma removal operations, respectively. During atrial septal defect closure operations, the average cardiopulmonary bypass time was $128.3{\pm}43.1$ minutes. The median length of stay was between five and seven days. The only complication was that one patient needed reoperation to address bleeding. There were no hospital mortalities. Conclusion: Robot-assisted cardiac surgery is safe and effective for mitral valve repair, atrial septal defect closure, and cardiac myxoma removal surgery. Reducing operative time depends heavily on the experience of the entire robotic surgical team.

• Journal of Chest Surgery
• /
• 제30권2호
• /
• pp.226-230
• /
• 1997

본 증례는 잦은 상기도 감염을 보였던 마제상폐를 동반한 양측성 엽내형 폐격리증의 성공적 치료에 대한 보고이다. 단순 흉부X-선상 양측 폐하엽 에 폐렴정 경화와 침윤을 보였으며 흉부전산화단층촬영상 폐격리증에 합당한 다발성 낭성병변을 보였다. 대동맥조영술에서 횡격막 상부에서 시작되어 양측 격리 폐로 유입되는 2개의 기 형체동맥을 관찰할 수 있었다. 좌측 개흉술을 통하여 좌측과 우측의 격리폐로 유입되는 체동맥을 결찰후 분리하고 좌하엽의 폐엽절제술을 시행한 다음 마제상폐의 협소부를 분리절 제후 우측 격리폐는 남겨두었다. 환자는 수술후 10일째 퇴원하였으며 잔류 우측 곁리폐의 합병증이나 증상없이 추적관찰중이다. 수술후 5개월깨 시행한 흉부전산화단층촬영상 남겨두었던 잔류 우측 격 리폐 는 자연 소실되었음을 관찰할수 있었다 본 증례로 보아 합병증이 없는 엽내형 격리폐에서 폐엽절제술 을 시행하지 않고 기형체동맥을 결찰분리만하는 새로운 치료방법을 제안해 보는 바이다.

• Childhood Kidney Diseases
• /
• 제10권2호
• /
• pp.213-218
• /
• 2006

Purpose : Nutcracker syndrome refers to compression of the left renal vein(LRV) between the aorta and superior mesenteric artery(SMA) that results in elevation of pressure in the LRV and development of collateral veins. It must be considered as a possible factor when hematuria or proteinuria occurs in a healthy child. The purpose of this study is to determine the time to spontaneous resolution in childhood nutcracker syndrome, and to observe whether this is affected by sex, age, proteinuria or initial ratio of peak velocity of LRV. Methods : We investigated 26 patients who were found to have spontaneous resolution by follow-up Doppler ultrasonography among 117 patients diagnosed with nutcracker syndrome by renal Doppler ultrasonography from May 2001 to December 2005. We determined the time to spontaneous resolution in childhood nutcracker syndrome, and observed whether the duration was affected by sex, age, proteinuria or initial ratio of peak velocity. Results : 26 patients(59%) achieved spontaneous resolution by 1.2 years(mean). The time to spontaneous resolution of childhood nutcracker syndrome in 26 patients was $16.71{\pm}9.99$ months(range 6.0-49.2). The time to spontaneous resolution was not affected by sex, age, proteinuria nor initial ratio of peak velocity of LRV. Conclusion : More than half of the patients who were diagnosed by renal Doppler ultrasonography achieved spontaneous resolution. The time to spontaneous resolution was not affected by sex, age, proteinuria nor initial ratio of peak velocity of LRV.

• 생약학회지
• /
• 제40권4호
• /
• pp.400-407
• /
• 2009

The purpose of this study is to investigate hypotensive effect of BDR-29, new herbal preparation of Cassiae Semen, Prunellae Spica, Uncariae Ramulus et Uncus, and Tribuli Semen, in stroke-prone spontaneously hypertensive rats (SHR-SP). SHR-SP were treated with BDR-29 at a dose of 100, 200 mg/kg/day orally for 13 weeks. In the BDR-29 treat group, mean blood pressure and systolic blood pressure were significantly reduced (p<0.05). In phenylephrine-precontracted arota and carotid artery, BDR-29 induced endothelium-dependent vascular relaxation. Hematological findings and biochemical examination revealed no evidence of specific toxicity related to BDR-29. In addition, BDR-29 was markedly attenuated intima-media thickness of thoracic aorta with progression of atherosclerosis. SHR-SP were treated with BDR-29 were significantly increased eNOS expression in arota. These results indicated that BDR-29 improves blood pressure as well as initial atherosclerotic lesion.

• Journal of Chest Surgery
• /
• 제25권3호
• /
• pp.289-295
• /
• 1992

We evaluated the correlationship between the predicted defect size at preoperative examination and the actual defect size at operation room, by examining 69 cases of ventricular septal defect operated at the deparment of Thoracic and Cardiovascular surgery, Kyungpook University Hospital from January 1988 to December 1990. We excluded cases associated with other cardiac anomalies. Of the 69 cases, 39 are male and 30 female, forming 1.3:1 sex ratio in males favor. Their age range from 6 months to 16 year, and 4.3 on the average Their body weights are from 6 to 45kg and 15 on the average. According to Soto`s classification, perimembranous type costitutes 42 cases[61%], doubly committed subarterial type 23 cases[33%], and muscular type 4 cases[6%]. The average diameter of defect size is 8.0$\pm$3.5mm measured in 2D-echocardiogram, 5.6$\pm$3.4mm in angiogram, and 7.4$\pm$4.4mm in operative field. There is statistically significant correlation between the size from 2D-echocardiogram and actual defect size[p=0.001], and no significant difference between the two. Especially in the cases without anurysmal formation, they are nearly the same. Cardiothoracic ratio, pulmonary to systemic flow ratio, pressure ratio and resistance ratio also have statistically significant correlation. Main pumonary artery to descending aorta diameter ratio is correlated with the actual defect size. There is statistically significant correlation between the size from angiogram and actual defect size with some difference.