• Journal of Chest Surgery
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• v.31 no.2
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• pp.118-124
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• 1998

Minimally invasive coronary artery bypass grafting without using cardiopulmonary bypass (CPB) is a recently accepted modality of myocardial revascularization prcedures which is particularly suitable to the patients with lesions in the left anterior descending(LAD) and the right coronary arteries. Of the consecutive 35 patients of coronary artery bypass grafting performed at Sejong General Hospital from March to August 1996, six patients underwent minimally invasive coronary artery bypass grafting without CPB. All had stenotic lesions of the LAD more than 90%. Bypass grafting of the LAD was approached through midline sternotomy in one, through ministernotomy in two, and through limited left anterior thoracotomy in three patients, respectively. The internal mammary arteries were prepared without the use of thoracoscope. The mobilized mammary arteries were connected directly to the LAD in 5 patients, and the anastomosis required interposition of a segment of the radial artery in the remaining one. The diagonal branch was revascularized with the saphenous vein graft at the same time in one patient. No blood transfusion was necessary in 2 patients, and average blood required during surgery was 800ml in 4 patients. All patients were extubated from 4 to 14 hours(mean 9 hours) after operation. Early postoperative coronary angiography in 5 patients between 7 and 10 days after surgery has proved full patency of the grafts. With these limited clinical experiences, the clinical results demonstrated that minimally invasive coronary artery bypass grafting without CPB is an useful procedure especially in patients with isolated lesion in the proximal LAD.

• Journal of Chest Surgery
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• v.36 no.7
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• pp.531-534
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• 2003

A 43-year-old woman who had had an invasive mole 5 years previously required emergent pulmonary embolectomy under cardiopulmonary bypass. Curative resection was impossible because the tumor invaded the right main pulmonary artery and left lower pulmonary artery. The pathologic diagnosis made by the tumor emboli specimens was choriocarcinoma. The patient received post-operative chemotherapy over a 6-month period and had complete remission. Although rare, choriocarcinoma should be considered in the differential diagnosis of fertile women presented with pulmonary embolism.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.3
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• pp.284-290
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• 2012

In this research, a new type of haptic master device using electrorheological(ER) fluid for minimally invasive surgery(MIS) is devised and control performance of the proposed haptic master is evaluated. The proposed haptic master consists of ER bi-directional clutch/brake for 2 DOF rotational motion(X, Y) using gimbal structure and ER brake on the gripper for 1 DOF rotational motion (Z). Using Bingham characteristic of ER fluid and geometrical constraints, principal design variables of the haptic master are determined. Then, the generation of torque of the proposed master is experimentally evaluated as a function of applied field of voltage. A sliding mode controller which is robust to uncertainties is then designed and empirically realized. It has been demonstrated via experiment that the proposed haptic master associated with the controller can be effectively applied to MIS in real field conditions.

• Smart Structures and Systems
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• v.11 no.3
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• pp.283-297
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• 2013

An innovative cage for spinal fusion surgery is presented within this work. The cage utilizes shape memory alloy for its hinge actuation. Because of the use of SMA, a smaller incision is needed which makes the cage deployment minimally invasive. In the development of the cage, a model for predicting the torsional behavior of SMAs was developed and verified experimentally. The prototype design of the cage was developed and manufactured. The prototype was subjected to static tests per ASTM specifications. The cage survived all of the tests, alluding to its safety within the body.

• Journal of Chest Surgery
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• v.26 no.11
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• pp.838-844
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• 1993

Rupture of aortic is for the most part a terminal disorder and requires prompt and aggressive treatment. Most of the patients who develop this condition outside the hospital die before appropriate therapy can be instituted. Thus prompt treatment, sometimes innovative, resulted in a highly significant survival rate. We experionced 21 aortic rupture due to mycotic aneurysm and another 3 due to chest trauma. Operation was done in 11 cases, and mortality was 3 of 11 cases. In another 10 cases, operation was not performed and all of them were expired. We confirmed diagnosis using only non invasive technic as ultrasonogram and computed tomography and invasive technic like aniography was absolutely avoided. Preoperative management was aimed to lower blood pressure for the purpose of preventing srcondary bleeding, and operantions erer porformed promptly if possible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.213-216
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• 2005

This paper presents force feedback control performance of a 3DOF haptic device that can be used for minimally invasive surgery (MIS). As a first step, a 3DOF electrorheological (ER) joint is designed using a spherical mechanism. And it is optimized based on the mathematical torque modeling. Subsequently, the master haptic device is manufactured by the spherical joint. In order to achieve desired force trajectories, model based compensation strategy is adopted for the ER master. Therefore, Preisach model fur the PMA-based ER fluid is identified using experimental first order descending (FOD) curves. A compensation strategy is then formulated through the model inversion to achieve desired force at the ER master. Tracking control performances for sinusoidal force trajectory are presented, and their tracking errors are evaluated.

• Journal of Korean Neurosurgical Society
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• v.62 no.3
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• pp.302-312
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• 2019

Stereoelectroencephalography (SEEG) is an invasive technique used during the surgical management of medically refractory epilepsy. The utility of SEEG rests in its ability to survey the three-dimensional organization of the epileptogenic zone as well as nearby eloquent cortices. Once concentrated to specialized centers in Europe and Canada, the SEEG methodology has gained worldwide popularity due to its favorable morbidity profile, superior coverage of deep structures, and ability to perform multi-lobar explorations without the need for craniotomy. This rapid shift in practice represents both a challenge and an opportunity for pediatric neurosurgeons familiar with the subdural grid approach. The purpose of this review is to discuss the indications, technique, and safety of long-term SEEG monitoring in children. In addition to reviewing the conceptual and technical points of the diagnostic evaluation, attention will also be given to SEEG-based interventions (e.g., radiofrequency thermo-coagulation).

• Journal of Chest Surgery
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• v.54 no.6
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• pp.554-557
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• 2021

Surgeons are increasingly using the right mini-thoracotomy approach to perform aortic valve surgery. This approach has shown better results in terms of blood loss and length of hospital stay than the sternotomy approach. For selected patients requiring aortic root and ascending aorta surgery, a right mini-thoracotomy approach may prove beneficial. In our technique, we placed a 5-cm horizontal skin incision in the right second intercostal space. Femoro-femoral cardiopulmonary bypass was established. A valved aortic conduit was used for aortic root replacement. The patient's postoperative course was uneventful, with a short hospital stay. This technique offers a minimally invasive approach to aortic root and ascending aorta surgery with easy adaptability and reduced costs.

• Journal of Chest Surgery
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• v.32 no.12
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• pp.1123-1126
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• 1999

Coronary artery bypass grafting (CABG) technique has been much developed but CABG under cardiopulmonary bypass has the unavoidable deficits such as generalized inflammatory reaction from cardiopulmonary bypass and myocardial ischemia from aortic-cross clamp. There has been remarkable advancement of CABG without cadiopulmonary bypass. We performed CABG successfully without cardiopulmonary bypass. We performed CABG successfully without cardiopulmonary bypass in two patients with multivessel coronary disease who were failed to intervene with percutaneous transluminal coronary angioplasty. We herein report the two cases.

• Journal of Chest Surgery
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• v.46 no.5
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• pp.388-390
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• 2013

With advancement of the technique of video-assisted thoracic surgery (VATS), some surgeons have made great efforts to reduce the number of incisions in the conventional three- or four-port approach. Several studies on cases treated by single-incision VATS and their short-term outcomes were reported. Here, we present our experience with single-incision VATS for the treatment of benign mediastinal diseases.