• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.304-310
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• 1999

This study was designed to find the effect of Minocycline loaded microcapsule applied locally to tissue by measuring drug concentration in tissue and serum by HPLC and to achieve optimal drug delivery system and duration to a specific target site. Control group were administrated minocycline intramuscularly twice a day with $0.2{\mu}g/100g$ for 1 to 10 days. In experimental group, surgical wound was created on Rt. cheek and then minocycline loaded microcapsule was applied into the space between superficial and deep layer of masseter muscle. Animals were sacrificed at 1, 3, 5, 7, 10 days after initial administration, blood was obtained from heart and right masseter muscle was excised. Blood sample was centrifuged at 3000rpm for 15min. Tissue sample was homogenized, left at room temperature for 48hr and centrifuged at 4000g for 5min. Supernatant was completely dried and dissolved in distilled water. Analysis was conducted using a ${\mu}Bondapack$ C18 column. The mobile phase was 0.2M Ammonium Oxalate/0.1M EDTA/DMF=11/4/5 solution, which was injected into the column and detected with photodiode detector at 344nm wavelength. The results were as follows : 1. This method was reliable, could be replicated and suitable for minocycline analysis in tissue as well as serum. 2. In tissue, concentration of minocycline of experimental group was higher than that of control group for 5days. 3. Except 1 day, concentration of minocycline in serum of experimental group was lower than that of control group. 4. Concentration of minocycline in tissue was much higher than that in serum. From these results, minocycline loaded microcapsule might be effective tool for local drug delivery system might be useful for treatment of infections of oral and maxillofacial region and management of infected surgical wound, minimizing systemic effects.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.289-293
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• 2006

By means of microsurgical free-tissue transfer providing a large amount of required tissue, the surgeon can resect tumoral tissue more safely, which allows tumor-free margins and enhances the reliability of the ablative surgery that otherwise could not be performed radically. The morbidity of elective free-tissue transfer seems to be quite low, carrying acceptable risks for most patients. But the elderly patients are at risk for cardiac and respiratory problems, deep vein thrombosis, pulmonary emboli and infection merely as a function of age. This study was undertaken to define further risks of the elderly population with regards to free-tissue transfer. We retrospectively reviewed our experience with 110 microsurgical free-tissue transfers for head and neck reconstruction in patients greater than 60 years of age. Microsurgical procedures in all cases were preformed by the plastic and reconstructive department at Yonsei medical center. The investigated parameters were patient demographics, past medical history, American Society of Anesthesiologists(ASA) status, site and cause of defect, the free tissue transferred and postoperative complication including free-flap success or failure. There were 46 patients in the age group from 60 to 64 years, 34 patients from 65 to 70 years, and 30 patients 70 years or older. There happened 3 flap losses, resulting in a flap viability rate of 97%. Patients with a higher ASA designation experienced more medical complication(p=0.05, 0.01, 0.03 in each age group I, II, III) but not surgical complication p=0.17, 0.11, 0.54 in each age group I, II, III). And the relationship between postoperative complication and age groups was not significant. These observations suggest that major determinant for postoperative medical complication be the patient's American Society of Anesthesiologists score, and chronologic age alone should not be an exclusion criterion when selecting patients for free-tissue transfer

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.353-358
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• 2013

Background Robots have allowed head and neck surgeons to extirpate oropharyngeal tumors safely without the need for lip-split incision or mandibulotomy. Using robots in oropharyngeal reconstruction is new but essential for oropharyngeal defects that result from robotic tumor excision. We report our experience with robotic free-flap reconstruction of head and neck defects to exemplify the necessity for robotic reconstruction. Methods We investigated head and neck cancer patients who underwent ablation surgery and free-flap reconstruction by robot. Between July 1, 2011 and March 31, 2012, 5 cases were performed and patient demographics, location of tumor, pathologic stage, reconstruction methods, flap size, recipient vessel, necessary pedicle length, and operation time were investigated. Results Among five free-flap reconstructions, four were radial forearm free flaps and one was an anterolateral thigh free-flap. Four flaps used the superior thyroid artery and one flap used a facial artery as the recipient vessel. The average pedicle length was 8.8 cm. Flap insetting and microanastomosis were achieved using a specially manufactured robotic instrument. The total operation time was 1,041.0 minutes (range, 814 to 1,132 minutes), and complications including flap necrosis, hematoma, and wound dehiscence did not occur. Conclusions This study demonstrates the clinically applicable use of robots in oropharyngeal reconstruction, especially using a free flap. A robot can assist the operator in insetting the flap at a deep portion of the oropharynx without the need to perform a traditional mandibulotomy. Robot-assisted reconstruction may substitute for existing surgical methods and is accepted as the most up-to-date method.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.714-719
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• 2009

Purpose: Recurrent ischial pressure sore is troublesome for adequate soft tissue coverage, because usually its pocket has a very large deep space and adjacent donor tissue have been scarred in the previous surgery. However, the conventional reconstructive methods are very difficult to overcome them. Modified gluteus maximus myocutaneous V - Y advancement flap from buttock can be successfully used in these circumstances. Methods: From February 2007 to October 2008, modified gluteus maximus myocutaneous V - Y advancement flaps were perfomed in 10 paraplegic patients with recurrent ischial pressure sore. The myocutaneous flap based on the inferior gluteal artery was designed in V - shaped pattern toward the superolateral aspect of buttock and was elevated from adjacent tissue. Furthermore, when additional muscular bulk was required to obliterate dead space, the flap dissection was extended to the inferolateral aspect which can included the adequate amount of the gluteal muscle. After the advanced flap was located in sore pocket, donor defect was repaired primarily. Results: The patients' mean age was 46.9 and the average follow - up period was 12.4 months. The immediate postoperative course was uneventful. But, two patients were treated through readvancement of previous flap due to wound dehiscence or recurrence after 6 months. The long - term results were satisfied in proper soft tissue bulk and low recurrence rate. Conclusions: The modified gluteus maximus myocutaneous V - Y advancement flap may be a reliable method in reconstruction of recurrent ischial pressure sore, which were surrounded by scarred tissue because of its repetitive surgeries and were required to provide sufficient volume of soft tissue to fill the large pocket.

• Journal of Oral Medicine and Pain
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• v.19 no.1
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• pp.33-43
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• 1994

The purpose of this paper was to observe the influence of Ga-As semiconductor-low power generating laser on she appearance and actions of tenascin, extracellular matrix, as healing process of intentional wound on the experimental animals is taking place. 35 rabbits were divided into control and experimental group. ; and on each, 3mm-long and 2mm-deep, surgical wounds were created on buccal oral mucosa and thoracodorsal portion of skin. Ga-As laser was applied to the experimental group starting a day of the day the wounds were created , the laser was applied for 5 minutes every other day. Tissue samples were taken after the 2, 4, 7, 10, and 14 days after wound formation. Then tile healing process of experimental and control groups were observed and compared, using light microscope. Afterwards, the samples were immunohistochemical stained and again observed tenascin by quantitative measuring. The following results were obtained : 1. Tenascin was observed prevalently on epithelial cells, border area of dermis, and interstitial matrix between connective tissue layers in both experimental and control groups. 2. In oral mucosa, the experimental group showed significant increase in the appearance of tenascin after 4 days compared to the control group, but after 10 days, it decreased to a point which is even less than the control group. 3. In the skin samples, the pattern of appearance of tenascin was the same in both groups, but there was some difference concerning when the peak period was shown, In the experimental group, the peak period of tenascin expression was the 7 days after wound formation in epithelium and connective tissue. In the control group, the peak period was 10 days after. 4. In both the experimental and control groups, tenascin first appeared in the epithelium near the wound area and submucosa, and then spread on the underlying connective tissue. In conclusion, appearance of tenascin is closely related to regeneration of epithelium and development of granulation tissue : therefore, low power laser, which fastnes appearance of tenascin, is sure to faciltate healing process of oral mucosa.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2410-2414
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• 2020

Heavy ions have a high potential for destroying deep tumors that carry the highest dose at the peak of Bragg. The peak caused by a single-energy carbon beam is too narrow, which requires special measures for improvement. Here, carbon-12 (¹²C) ion with different energies has been used as a source for calculating the dose distribution in the water phantom, soft tissue and bone by the code of Monte Carlobased FLUKA code. By increasing the energy of the initial beam, the amount of absorbed dose at Bragg peak in all three targets decreased, but the trend for this reduction was less severe in bone. While the maximum absorbed dose per bone-mass unit in energy of 200 MeV/u was about 30% less than the maximum absorbed dose per unit mass of water or soft tissue, it was merely 2.4% less than soft tissue in 400 MeV/u. The simulation result showed a good agreement with experimental data at GSI Darmstadt facility of biophysics group by 0.15 cm average accuracy in Bragg peak positioning. From 200 to 400 MeV/u incident energy, the Bragg peak location increased about 18 cm in soft tissue. Correspondingly, the bone and soft tissue revealed a reduction dose ratio by 2.9 and 1.9. Induced neutrons did not contribute more than 1.8% to the total energy deposited in the water phantom. Also during ¹²C ion bombardment, secondary fragments showed 76% and 24% of primary 200 and 400 MeV/u, respectively, were present at the Bragg-peak position. The combined treatment of carbon ions with neutron or electron beams may be more effective in local dose delivery and also treating malignant tumors.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.122-127
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• 2011

A 5-year old, intact male, Cocker spaniel dog was referred with paraplegia and loss of deep pain perception. Physical, neurological examinations, radiography, and computed tomography were evaluated. Based on the clinical examinations, the dog was diagnosed with severe disc herniation ($L_2$ to $L_3$ intervertebral disc space). On the next day of presentation (6 days after loss of deep pain perception), hemilaminectomy was performed. After decompression of spinal cord and removal of herniated disc materials, $1{\times}10^6$ canine allogenic adipose tissue-derived mesenchymal stem cells (MSCs) diluted by $50{\mu}l$ saline were directly applied to the injured site of the spinal cord. Ten weeks of follow-up after surgery, full recovery of deep pain perception and motor function were evaluated in both hind limbs. Based on the result, we suggest that the transplantation of allogenic adipose tissue-derived MSCs to dogs with spinal cord injuries could be a considerable method to expect better clinical outcomes in veterinary practice.

• Journal of the Korean Society of Systems Engineering
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• v.15 no.2
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• pp.72-78
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• 2019

Pathology is the motor that drives healthcare to understand diseases. The way pathologists diagnose diseases, which involves manual observation of images under a microscope has been used for the last 150 years, it's time to change. This paper is specifically based on tumor detection using deep learning techniques. Pathologist examine the specimen slides from the specific portion of body (e-g liver, breast, prostate region) and then examine it under the microscope to identify the effected cells among all the normal cells. This process is time consuming and not sufficiently accurate. So, there is a need of a system that can detect tumor automatically in less time. Solution to this problem is computational pathology: an approach to examine tissue data obtained through whole slide imaging using modern image analysis algorithms and to analyze clinically relevant information from these data. Artificial Intelligence models like machine learning and deep learning are used at the molecular levels to generate diagnostic inferences and predictions; and presents this clinically actionable knowledge to pathologist through dynamic and integrated reports. Which enables physicians, laboratory personnel, and other health care system to make the best possible medical decisions. I will discuss the techniques for the automated tumor detection system within the new discipline of computational pathology, which will be useful for the future practice of pathology and, more broadly, medical practice in general.

• Journal of Multimedia Information System
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• v.3 no.3
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• pp.97-102
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• 2016

Deep learning enables machines to have perception and can potentially outperform humans in the medical field. It can save a lot of time and reduce human error by detecting certain patterns from medical images without being trained. The main goal of this paper is to build the optimal model for breast mass classification by applying various methods that influence the performance of Convolutional Neural Network (CNN). Google's newly developed software library Tensorflow was used to build CNN and the mammogram dataset used in this study was obtained from 340 breast cancer cases. The best classification performance we achieved was an accuracy of 0.887, sensitivity of 0.903, and specificity of 0.869 for normal tissue versus malignant mass classification with augmented data, more convolutional filters, and ADAM optimizer. A limitation of this method, however, was that it only considered malignant masses which are relatively easier to classify than benign masses. Therefore, further studies are required in order to properly classify any given data for medical uses.

• Journal of Korean Neurosurgical Society
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• v.29 no.6
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• pp.815-821
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• 2000

Parasplenial arteriovenous malformations(AVMs) are rare vascular malformations which have distinct clinical and anatomical features. They are situated at the confluence of the hippocampus, isthmus of the cingulate gyrus and the gyrus occipitotemporalis medialis. These lesions are anterior to the calcarine sulcus and their apex extends towards the medial surface of the trigonum. Posterolaterally, these lesions are in close proximity to the visual cortex and optic radiation. The objectives in the surgery of parasplenial AVMs are complete resection of the lesions and preservation of vision. These objectives must be achieved with comprehensive understanding of the following anatomical features :1) the deep central location of the lesions within eloquent brain tissue ; 2) the lack of cortical representation of the AVMs that requires retraction of visual cortex ; 3) deep arterial supply ; 4) deep venous drainage ; 5) juxtaposition to the choroid plexus with which arterial supply and venous drainage are shared. A 16-year-old female student presented with intraventricular hemorrhage from a right parasplenial-subtrigonal AVM. The lesion, fed by posterior cerebral artery and drained into the vein of Galen, was successfully treated by the inter-hemispheric parietooccipital approach. To avoid visual field defect a small incision was made on precuneus anterior to the calcarine sulcus. In this report, the authors describe a surgical approach with special consideration on preservation of visual field.