• 대한정형외과학회지
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• 제54권6호
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• pp.509-518
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• 2019

목적: 악성 종양 환자에서 림프절 전이를 발견하는 것은 초기에 정확한 병기 및 예후와 관련된 정보를 알 수 있고 수술 후 보조치료(adjuvant therapy)의 필요성을 평가해서 조기에 치료를 할 수 있도록 해주기 때문에 중요하다. 본 연구를 통해 정형외과 영역의 악성 종양 환자를 평가함에 있어 양전자 방출 컴퓨터 단층 촬영기(positron emission tomography/computed tomography, PET/CT)가 sentinel lymph node biopsy와 비교하여 유용한지를 알아보고자 한다. 대상 및 방법: 2008년부터 2018년까지 악성 근골격계 종양으로 진단받고 PET/CT를 촬영한 환자 251명 중 72명의 환자를 선별하여 후향적 분석을 시행하였다. 림프절 전이가 의심되는 환자군은 조직검사를 시행하였다. 분석은 의무기록, 임상정보, PET/CT 영상 및 판독 소견, 병리 결과를 통해 시행하였으며, 임상경과 및 병리검사 결과를 PET/CT 결과와 비교하여 PET/CT의 정확도를 평가하였다. 결과: 환자의 나이는 14세에서 88세까지 분포하였고, 평균 추시 기간은 2.4년이었으며, 22명에서 림프절의 전이가 확인되었다. 육종 및 비육종 종양에서 PET/CT 영상의 민감도, 특이도, 양성예측도, 음성예측도는 전문가의 소견을 함께 고려할 경우 상당히 상승하는 것을 확인하였다. 결론: 본 연구를 통하여 전문가의 소견을 함께 고려한다면, 림프절의 전이를 발견하는 데 PET/CT의 유용성은 증가할 것으로 생각된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권4호
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• pp.391-396
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• 2006

The CT number is called Hounsfield unit(HU). Generally HU has a score between +1000 from -1000, and it is standardized usingthe air(-1000), water(0), and compact bone(+1000). Hounsfield Unit to standardize the density in computed tomography using the air and water has been used to analysis of lesion in other medical field. Computed tomography is popular method to analysis of lesion in oral & maxillofacial field but the analysis about density of lesion by Hounsfield unit is still obscure. For this study, computed tomography taken in Dankook University Dental Hospital and Hounsfield unit was measured to compare the difference of jaw bone lesion as cystic lesion, benign tumor, malignant tumor.

• 치과방사선
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• 제24권2호
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• pp.413-423
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• 1994

The purpose of this study was to clarify the spatial relationship in presurgical examination and to aid surgical planning and postoperative evaluation of patients with facial bone injury. For this study, three-dimensional images of facial bone fracture were reconstructed by computed image analysis system and three-dimensional reconstructive program integrated in computed tomography. The obtained results were as follows: 1. Serial conventional computed tomograms were value in accurately depicting the facial bone injuries and three-dimensional reconstructive images demonstrated an overall look. 2. The degree of deterioration of spatial resolution was proportional to the thickness of the slice. 3. Facial bone fractures were the most distinctly demonstrated on inferoanterior views of three-dimensional reconstructive images. 4. Although three-dimensional reconstructive images made diagnosis of fracture lines, it was difficult to identify maxillary fractures. 5. The diagnosis of zygomatic fractures could be made equally well with computed image analysis system and three-dimensional reconstructive program integrated in computed tomography. 6. The diagnosis of mandibular fractures could be made equally well with computed image analysis system and three-dimensional reconstructive program integrated in computed tomography.

• 한국임상수의학회지
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• 제32권1호
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• pp.69-72
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• 2015

This study was performed to differentiate calcium oxalate and struvite canine urinary stones using computed tomography. A total of 38 urinary stones (8 calcium oxalate and 30 struvite) were scanned using a computed tomography scanner. These urinary stones (10-15 mm diameter) extracted surgically without fragmentation were obtained from the different individual patients. The stone's Hounsfield units(HU) values, heterogenicity, and roughness of surface were evaluated to differentiate calcium oxalate and struvite. The HU values of calcium oxalate were significantly higher than those of struvite. A receiver operator characteristic (ROC) curve revealed 1272 as the best threshold value to distinguish calcium oxalate from struvite (ROC curve AUC 0.87, p < 0.0014). The heterogenicity of calcium oxalate and struvite significantly differed on bone and dental window setting (p < 0.0001). There was no significant difference between calcium oxalate and struvite in roughness of surface. On computed tomographic images, bone and dental windows setting were useful for evaluation of heterogenicity between calcium oxalate and struvite. The HU value and heterogenicity are highly promising factor that can distinguish calcium oxalate and struvite with reasonable accuracy.

• 한국임상수의학회지
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• 제35권6호
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• pp.290-293
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• 2018

Signalment: A dog which had been hit by car a month prior and had been experiencing recurrent pleural chyle effusion was referred to Chung-buk National University Animal Medical Center. The clinical signs included tachypnea and salivation. Results: Ultrasound-guided popliteal lymphography was performed. The computed tomography imaging revealed that the thoracic duct was ruptured and the lymph was leaking into the cranial mediastinal region. After this discovery, thoracic duct ligation was performed. The ultrasound-guided popliteal lymphography was repeated after the surgery. The second computed tomography imaging revealed that the thoracic duct rupture was resolved. Clinical relevance: We identified the etiology of chylothorax through the computed tomographic lymphography and imaged specific leakage areas. After surgery, the computed tomography imgaing confirmed the lymphatic flow modification and the treatment was successful.

• 한국임상수의학회지
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• 제21권2호
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• pp.184-186
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• 2004

A castrated male, 6 year-old Shih-Tzu, weighing 4.6 kg with a discharge from the external ear canal and a mal-odor was referred to Verterinary Medical Teaching Hospital, Seoul National University. Radiographic findings were narrowing and focal loss of an air density in the left ear canal and bilateral thickening of the osseous bullae. For more detail examination, computed tomography was used. In computed tomographic findings, bilateral thickening of the bulla wall and increased opacity of the bulla space were observed. Thus this dog was diagnosed as bilateral otitis media. Then surgical correction, total ear canal ablation, was performed successfully and the patient showed a good prognosis thereafter. It is considered that computed tomography might serve as an useful imaging tool for otitis media and that it supplies information not obtained with a conventional radiography.

• 한국임상수의학회지
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• 제20권4호
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• pp.519-522
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• 2003

An appearance of herniated intervertebral disc into thoracolumbar vertebral canal was evaluated in two patients using computed tomography (CT). Before CT scanning, plain radiography and myelography were performed in both cases. CT images were compared to those of myelography. Dogs were positioned in sternal recumbency under inhalation anesthesia and transverse slices with 2 mm thickness were obtained around thoracolumbar region. The transverse CT images were examined using both vertebral and spiral window mode. The most common findings on CT images were loss of vertebral canal epidural fat, bulging of vertebral canal disc margins, displacement of spinal cord and flatted vertebral canal. Whereas, narrowed intervertebral disc space and simple extradural pattern were the main findings on plain and contrast radiographs. CT imges showed the extent of the herniated disc lesion, type II intervertebral disc hernation, and the displacement of spinal cord in detail in both occations. It is considered that degree and precise localization of the intervertebral disc herniation and subtle lesion of spinal cord could be identified accurately using computed tomography.

• 치과방사선
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• 제28권2호
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• pp.363-385
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• 1998

In orthodontics and orthognathic surgery. cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery. too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipments and because of its expenses and amount of exposure to radiation. limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram. pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms. and for validation of new method. in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery. computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of dry skull that position of mandible was displaced. range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -1.8 mm to 1.8 mm and 94％ in displacement of all co-ordinates values was from -1.0 mm to 1.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). 2. In four cases of orthognathic surgery patients, range of displacement between computer­simulated three dimensional images and actual postoperative three dimensional images in coordinates values was from -6.7 mm to 7.7 mm and 90％ in displacement of all co-ordinates values was from -4.0 to 4.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). Conclusively. computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms. Therefore. potentiality that can construct postoperative three dimensional image without three dimensional computed tomography after surgery was presented.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1367-1368
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• 2013

• 한국정밀공학회지
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• 제25권1호
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• pp.35-42
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• 2008