• 대한의용생체공학회:의공학회지
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• 제26권4호
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• pp.193-197
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• 2005

Shunt valves used to treat patients with hydrocephalus were tested to investigate influence of intracranial pressure pulsation on their flow control characteristics. Five commercial shunt valves were tested in the flow loop that simulates pulsed flow under pressure pulsation. As 20cc/hr of flow rate was adjusted at a constant pressure, application of $40mmH_2O$ of pressure pulse increased the flow rate by $67.9\%.$ As a 90cm length catheter was connected to the valve outlet, increase in the flow rate was substantially reduced to $17.5\%.$ As the flow rate was adjusted to 40cc/hr at a constant pressure, increase in the flow rate was $51.1\%$ with the same pressure pulsation of $40mmH_2O$. The results indicated that pressure-flow control characteristics of shunt valves implanted above human brain ventricle is quite different from those obtained by syringe pump test at constant pressures right after manufacture. The influence of pressure pulsation was observed to be more significant at low flow rate and the flexibility of the outlet silicone catheter was estimated to significantly reduce flow increase due to pressure pulsation.

• 대한한의학회지
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• 제35권1호
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• pp.1-9
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• 2014

Objectives: This study was to propose a standardized method of retention enema by extracting elements associated with published experimental methods of retention enema. Methods: 1) Literature search (1) Data sources: Retrieval was made, using 'Enema' or 'Retention Enema' as search words in Medline, Cochrane library, KISS, RISS, and KDSL DB. (2) Study selection: Two authors excluded irrelevant papers and chose qualified abstracts from the rest of the papers. The chosen studies were reviewed fully by the authors so that they could screen the significant papers based on the exclusion criteria. (3) Data extraction: Data on the total number of subjects, the target disease, the animal species, the type, quality, length, and diameter of catheter, the insertion length of catheter, the sample, the sample volume, the process of retention enema and the number of retention enemas performed were extracted from the selected studies. 2) Performing preliminary experiments about the elements associated with experimental methods of retention enema. Results & Conclusions: The standardized experimental method is as follows: animal: 280-320g SD rat 1) inserting a rectal tube of 8 Fr that measures 8 cm into the animal's anus, 2) injecting herbal medicines at the volume of 6ml and 3) holding them for 10 minutes.

• 대한방사선기술학회지:방사선기술과학
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• 제45권4호
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• pp.299-304
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• 2022

This study uses the 'S-align' function to present a reference value of the X-ray tube angle for the realization of an image similar to that of the chest PA image during chest AP radiography. This study targeted dummy phantom and used a 17"×17" DR image receptor. The irradiation conditions were 110 kVp, 160 mA, 50 ms, and the distance between the central X-ray and the image receptor was set to 180 cm and 110 cm, respectively. The end of the catheter was placed at the 11th thoracic height to indicate the nasogastric tube. In the case of lung apex length measurement, the mean value of measurement was 30.53±0.47 in PA. T 0°, TCA 5~25°, TCE 5~15° were 21.07±0.29, 27.60±0.21, 34.13±0.44, 39.86±0.31, 45.96±0.61 mm, 54.13±0.37 mm, 16.16±0.46 mm, 9.81±0.35 mm, 2.75±0.30 mm, respectively. For the depth of the catheter end, the average value measured at PA was 6.70±0.31 mm. T 0°, TCA 5~25°, TCE 5~15° were 15.72±0.38 mm, 24.10±0.50 mm, 29.24±0.86 mm, 34.35±0.35 mm, 41.06±1.08 mm, 48.07±0.38 mm, 12.85±0.25 mm, 7.92±0.36 mm, 3.01±0.39 mm, respectively. The length of the lung apex was similar to that of chest PA when the angle of incidence was adjusted from 5° to 10° in the leg direction, and the depth of the catheter tip was most similar when the X-ray tube angle was incident at 10° in the head direction. Therefore, To change the X-ray tube angle according to the purpose of the examination during the chest AP radiography using 'S-align' function is considered necessary.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.4103-4103
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• 2001

The aim of this study was to examine whether near infrared spectroscopy (NIRS) is an acceptable tool to determine cholesterol and collagen in human atherosclerotic plaque without destruction of the analyzed areas and without danger the endothelial cells - three preconditions for the development of a NIR-heart-catheter. The questions were: Can the cholesterol and collagen content of the arterial intima be estimated with acceptable precision in vitro by NIRS despite the matrix inhomogeneity of the plaques and their anatomic variability\ulcorner How deep can such NIR radiation penetrate into arterial tissue without danger for endothelial cells\ulcorner Is this penetration sufficient for information on the lipid and collagen accumulation\ulcorner Using NIRS, cholesterol and collagen can be determined with acceptable precision in model mixtures and human aortic specimens (r=0,896 to 0,957). The chemical reference method was HPLC. The energy dose was 71 mW/$cm^{-2}$ using a fiber optic strand with a length of 1.5m and an optical window of d=4mm. This dose appears to be not dangerous for endothelial cells, It will be attenuated to 50% by a arterial tissue of about 170-$200\mu\textrm{m}$ thickness. The results are also acceptable using a thin coronary catheter-like fiber optic strand (d=1mm).

• 한국의학물리학회지:의학물리
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• 제28권2호
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• pp.39-44
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• 2017

This study aims to analyze dose distribution and treatment time of endobronchial brachytherapy (EBBT) by changing the position step size of the dwell position. A solid water phantom and an intraluminal catheter were used in the treatment plan. The treatment plans were generated for 3, 5, 7, and 10 cm treatment lengths, respectively. For each treatment length, the source position step sizes were set as 2.5, 5, and 10 mm. Three reference points were set 1 cm away from the central axis of the catheter, along the axis, for uniform dose distribution. Volumetric dose distribution was calculated to evaluate the dosimetric effect. The total radiation delivery time and total dwell time were estimated for treatment efficiency, which were increased with position step sizes. At half-life time, the differences between the position step sizes in the total radiation delivery time were 18.1, 15.4, 18.0, and 24.0 s for 3, 5, 7, and 10 cm treatment lengths, respectively. The dose distributions were more homogenous by increasing the position step sizes. The dose difference of the reference point was less than 10%. In brachytherapy, this difference can be negligible. For EBBT, the treatment time is the key factor while considering the patient status. To reduce the total treatment time, EBBT can be performed with 2.5 mm position step size.

• 한국의학물리학회지:의학물리
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• 제10권1호
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• pp.1-7
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• 1999

본 연구에서는 $\beta$선 방출 동위원소들 중에서 $^{32}$P으로부터 방출되는 $\beta$선에 의한 홉수선량 분포를 방사선원의 형태와 기하학적인 조건을 달리하여 컴퓨터를 이용한 모사실험을 통해 예측함으로써 balloon catheter 및 radioactive stent의 이용과 관련된 정보를 얻고자한다. $^{32}$p로부터 방출된 $\beta$선이 인체내에서 에너지를 전달하는 과정에 대한 모사실험은 EGS4 code system 을 이용하여 수행되었다. 인체내의 방사선 흡수선량은 선원의 형태와 위치를 고려하여 축방향과 반경방향으로 등간격으로 나누어 각 격자에서 계산되었다. $^{32}$P 에서 방출되는 $\beta$선 에너지는 Coulomb 포텐셜에 대한 Dirac방정식의 해를 이용하여 계산된 $\beta$선 스펙트럼의 결과를 사용하여 무작위로 선정되었다. 체적 선원과 표면선원에서 시료 표면으로부터 반경방향으로 깊이 0.5 mm내에 있는 표적체에서의 선량률은 각각 12.133 cGy/s per GBq (0.449 cGy/s per mCi, uncertainty: 1.51%)와 24.732 cGy/s per GBq (0.915 cGy/s per mCi, uncertainty: 1.01 %)이다. 선량률은 시료표면으로부터 축방향과 반경방향으로의 거리에 따라 감소한다. 본 연구 결과를 근거로하여 balloon catheter 및 radioactive stent에 $^{32}$P 핵종을 사용할 때 치료선량을 20 Gy로 할 경우 치료에 적합한 초기 방사능량은 각각 29.69 mCi(치료시간을 3분으로 제한할 때) 와 1.2278 $\mu$Ci (영구삽입)로 계산되었다. 또한 원통형 체적선원과 표면선원에 대하여 초기방사능의 크기를 1 mCi/ml의 방사능 체적 밀도와 0.1 mCi/$cm^2$의 방사능 면 밀도로 나타내었을 때 각 표적체에서의 흡수선량률을 계산하였다. 통일한 값의 방사능 체적 밀도와 방사능 면 밀도는 크기가 다른 모델에 대해서 비슷한 크기의 홉수선량을 유도하므로 $^{32}$p 방사선원의 초기 방사능 체적 밀도와 초기 방사능 면 밀도를 알고 있을 때 본 연구의 계산 결과를 이용하면 직경과 길이가 다른 $^{32}$P 핵종의 원통형 모델 주위의 홉수선량 분포를 쉽게 계산할 수 있다.

• 사상체질의학회지
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• 제25권2호
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• pp.108-114
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• 2013

Objectives This study was aimed to review a standardized method of retention enema by extracting elements associated with methods of retention enema from papers involved. Methods 1) Data sources : Retrieval was made, using 'Enema' or 'Retention Enema' as search words in MEDLINE, The Cochrane Library, KISS, RISS, and NDSL DB. 2) Study selection : Two authors excluded irrelevant papers and chose qualified abstracts in the rest of the papers. The chosen studies were reviewed fully by the authors so that they could screen the significant papers based on the exclusion criteria. 3) Data extraction : Data on the total number of subjects, the target disease, the type, quality, length, diameter of catheter, the insertion length of catheter, the sample, the sample volume, the process of retention enema and the number of performing retention enema were extracted from the selected studies. Results & Conclusions The retention enema can be applied to gastrointestinal diseases, genitourinary diseases, metabolic diseases such as hypertension and diabetes, headaches and neurological disorders. The standardized treatment method is as following: 1) inserting a rental tube of 18-28 Fr that measures 20 to 30 cm into the patient's anus, 2) injecting herbal medicines which have purgative action or benefit on stomach and intestinal tract at the rate of 4 ml/min, and 3) holding them for 10 to 15 minutes.

• 종양간호연구
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• 제11권1호
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• pp.1-8
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• 2011

Purpose: The purpose of this study was to identify the types of venous access devices (VAD) for cancer patients and investigate the factors related to the insertions of central venous catheter (CVC) in cancer patients. Methods: The subjects were 379 cancer patients. A retrospective review of all patients who were discharged from a cancer unit from November 1st to 21st in 2008 was done using a structured questionnaire. Results: A total of 82 CVC (21.6%) was inserted among 379 patients for administering anticancer therapy. There were statistically significant differences in age, length of stay (LOS), cumulative LOS, medical department, history of CVC insertion, cancer category, and albumin level between patients using peripheral intravenous (IV) catheters and CVC. In addition, factors influencing the use of CVC were LOS (odds ratio [OR]=0.286, confidence interval [CI]=1.043-1.124), history of CVC insertion (OR=3.920, CI=0.128-0.637), albumin level (OR=1.010, CI=1.879-8.179), cumulative LOS (OR=1.010, CI=1.001-1.018), and hematological diseases (OR=4.863, CI=2.162-10.925). Conclusion: We found that central venous catheterization for anticancer therapy was minimal even though CVC was safe and effective device for IV access. It is necessary to develop a strategy to use VADs efficiently and timely for cancer patients.

• Archives of Plastic Surgery
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• 제39권3호
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• pp.253-256
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• 2012

A radial forearm free flap has been conventionally used for urethral reconstruction. However, aesthetic and functional complications occur frequently at the donor site. The use of a superficial circumflex iliac artery perforator (SCIP) flap can resolve these disadvantages. Here, we report our case with a review of literature. A 69-year-old man visited our hospital with multiple contusions of the abdomen and genital amputation. After necrotic tissue debridement, the length of the residual corpus carvernosum was 1.5 cm and that of the corpus spongiosum and urethra was 1 cm. For the reconstruction of the penis, a SCIP flap and anterolateral thigh free flap was performed. The primary closure was performed at the donor site. Three weeks postoperatively, the patient had a urethral foley catheter removed. The neourethra was functioning well without stricture. Four months postoperatively, the patient had no complications such as urethral stricture. A good recovery was also achieved with no aesthetic deficits at the donor site. SCIP flap is appropriate for urethral reconstruction. Because of its proximity to the recipient sites, it makes surgical preparation easier and the primary closure at the donor site available. It is also advantageous in that its location is almost unnoticeable.

• Journal of Chest Surgery
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• 제30권8호
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• pp.747-751
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• 1997

폐동맥협착을 시행한 환아에서 수술직후 변화하는 혈역학에 대응하기 위하여 피하조직에 위치시켜 쉽게 조절할 수 있는 기구를 개발하였다. stainless steel wire를 이용하여 스프링을 만든후 이것의 표면을 PTFE로 덮은 형태로 제작하였으며 스프링 내부로 wire를 통과시켜 이것을 올가미 형식으로 죄는 방법으로 협착을 할 수 있게 하였으며 협착의 정도를 피하조직으로 통하는 투명한 tube에 1mm간격으로 표시하여 알수 있게 하였다. 6마리의 개의 하행대동맥에 협착을 시행하였다. 수술후 1,2일째에도 이완과 협착을 효과적으로 유도 할수 있었으며 3개월후 어느정도의 혈관손상은 있었으나 큰 협병증 없이 유지함을 보였다. 비록 실험적인 연구이지만 인체에 삽입할수 있는 재료로 쉽게 기구제작이 가능하며 앞으로 피하를 열고 조절가능한 폐동맥협착술에 이용할 수 있으리라 생각된다.