• 제목/요약/키워드: Segmental scan

검색결과 31건 처리시간 0.026초

Impact of scanning strategy on the accuracy of complete-arch intraoral scans: a preliminary study on segmental scans and merge methods

  • Mai, Hai Yen;Mai, Hang-Nga;Lee, Cheong-Hee;Lee, Kyu-Bok;Kim, So-yeun;Lee, Jae-Mok;Lee, Keun-Woo;Lee, Du-Hyeong
    • The Journal of Advanced Prosthodontics
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    • 제14권2호
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    • pp.88-95
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    • 2022
  • PURPOSE. This study investigated the accuracy of full-arch intraoral scans obtained by various scan strategies with the segmental scan and merge methods. MATERIALS AND METHODS. Seventy intraoral scans (seven scans per group) were performed using 10 scan strategies that differed in the segmental scan (1, 2, or 3 segments) and the scanning motion (straight, zigzag, or combined). The three-dimensional (3D) geometric accuracy of scan images was evaluated by comparison with a reference image in an image analysis software program, in terms of the arch shape discrepancies. Measurement parameters were the intermolar distance, interpremolar distance, anteroposterior distance, and global surface deviation. One-way analysis of variance and Tukey honestly significance difference post hoc tests were carried out to compare differences among the scan strategy groups (α = .05). RESULTS. The linear discrepancy values of intraoral scans were not different among scan strategies performed with the single scan and segmental scan methods. In general, differences in the scan motion did not show different accuracies, except for the intermolar distance measured under the scan conditions of a 3-segmental scan and zigzag motion. The global surface deviations were not different among all scan strategies. CONCLUSION. The segmental scan and merge methods using two scan parts appear to be reliable as an alternative to the single scan method for full-arch intraoral scans. When three segmental scans are involved, the accuracy of complete arch scan can be negatively affected.

기관지확장증 환자에서 환기 폐주사의 임상적 의의 (Clinical Significance of $^{99m}Tc-DPTA$ Ventilation Scan in Patient with Bronchiectasis)

  • 박춘식;백승호;어수택;나현;최득린;김기정
    • 대한핵의학회지
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    • 제19권2호
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    • pp.57-63
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    • 1985
  • To evaluate the clinical significance of lung ventilation scan using $^{99m}Tc-DTPA$ in patient with bronchiectasis, we compared the involovement area of bronchogram and lung ventilation scan according to lobar and segmental distribution. There were no correlation between impairment of pulmonary function test and the number of bronchiectatic lobe and segment(p>0.5). Lung ventilation scan showed 66.7% of sensivity, 100% of specificity, ana 91.7% of accuracy according to lobar distribution, and 51.9% of sensivity, 96.9% of specificity, and 88.9% of accuracy according to segmental distribution. These results suggest that lung ventilation scan can be used as diagnostic tool in patient with bronchiectasis in whom bronchogram is not tolerable.

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위축성 신반흔의 위험인자 (Risk Factors for Atrophic Renal Scar)

  • 이정원;김현진;이승주
    • Childhood Kidney Diseases
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    • 제9권2호
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    • pp.193-200
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    • 2005
  • 목 적 : 위축성 신반흔은 소아기 고혈압과 만성 신부전의 중요한 원인이다. 위축성 신반흔의 위험요인을 평가하고자 하였다. 방 법 : 1995년에서 2003년까지 이화의대 목동병원에 첫 발열성 요로감염으로 입원하여 시행한 $^{99m}Tc-DMSA$ 신스캔에서 신장의 크기가 전반적으로 작아진 위축성 신반흔을 보인 41명을 대상으로 하였다. 위축성 신반흔은 $^{99m}Tc-DMSA$ 신스캔에서 상대적 신섭취가 10$\%$ 미만인 중증 위축성 신반흔(n=14)과 10-35$\%$인 경증 위축성 신반흔(n=27)으로 구분하였다. 신반흔은 첫 번째 신스캔에서 확인된 경우는 선천성으로, 급성 신우신염 후 추적 신스캔에서 신반흔으로 진행된 경우는 후천성으로 정의하였다. 대조군은 분절성 신반흔으로 진단된 소아 중 무작위로 선택된 41명이었다. 위축성 신반흔의 발생시기, 성별에 따른 차이와 방광요관역류의 정도 및 ACE 유전자 다형성 등의 위험요인을 조사하였다. 결 과 : 위축성 신반흔군의 연령별 분포는 분절성 신반흔군과 유의한 차이가 없었다. 선천성 신반흔은 위축성 신반흔군에서 61.0$\%$(25/41)로 분절성 신반흔군의 9.8$\%$(4/41)에 비하여 유의하게 많았다(P<0.01). 성볕분포는 위축성 신반흔군에서 남아 58.3$\%$(28/41), 여아 ,31.7$\%$(13/41)이였으며 이는 분절성 신반흔군의 남아 41.4$\%$(17/41), 여아 58.6$\%$(24/41)에 비하여 유의하게 남아의 비율이 높았다(P<0.05). 방광요관역류의 동반률은 위축성 신반흔군에서 92.7$\%$(38/41)로 분절성 신반흔군의 53.7$\%$(22/41)에 비하여 유의하게 높았다(P<0.05). 방광요관역류가 동반되지 않은 경우는 위축성 신반흔과 분절성 신반흔간에 남녀비의 유의한 차이가 없었으나 방광요관역류가 동반된 경우에는 남아의 비율이 중증 위축성 신반흔군에서 85.7$\%$(12/14)로 분절성 신반흔군의 45.5$\%$(10/22)에 비하여 유의하게 높았다(P<0.05). ACE 유전자 다형성은 위축성 신반흔과 분절성 신반흔군 사이에 유의한 차이가 없었다(P>0.05). 결 론 : 위축성 신반흔은 생후 예방이 불가능한 선천성이 많았고 위험요인에는 남아와 방광요관역류가 중요하였다. ACE 유전자 다형성은 위축성 신반흔의 위험 요인으로 작용하지 않았다.

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Tc-99m DISIDA 간담도 신티그라피에서 간 실질의 분절형 배설지연의 임상적 의의 (Clinical Significance of Segmental Parenchymal Excretion Delay on Tc-99m DISIDA Hepatobiliary Scan)

  • 강도영;류진숙;문대혁;이성구;김명환;이희경
    • 대한핵의학회지
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    • 제32권2호
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    • pp.161-167
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    • 1998
  • 목적: Tc-99m DISIDA 신티그라피에서 간 실질에 분절형으로 배설지연을 보이는 소견은 분절형 간내담관폐쇄의 소견으로 보고되고 있으나, 이러한 소견의 분절형 간내 담관폐쇄에서의 진단적 가치는 알려져 있지 않다. 본 연구에서는 간 실질 분절형 배설지연 소견의 분절형 간내 담관폐쇄 진단에서의 양성예측도와, 방사선학적 검사와 비교한 진단적 가치를 알고자하였다. 대상 및 방법: Tc-99m DISIDA 신티그라피에서 간 실질에 분절형 배설지연 소견을 보인 43명의 환자(48개 영상)를 대상으로하여 그 원인을 분석하고, 1개월 이내에 시행된 CT와 US와 비교하였다. 결과: 31예는 ERC나 PTC에 의해, 13예는 임상적 경과 관찰에 의해 분절형 담도 폐쇄가 확진되었고, 4예는 원인이 규명되지 않았다. 분절형 담관폐쇄에 대한 Tc-99m DISIDA 간담도 신티그라피의 양성예측도는 92% (44/48)이었다. US의 28%(5/ 18), CT의 13% (5/38)는 정상 소견이고, US의 17% (3/18), CT의 18% (7/38)에서는 담관 확장 소견만이 있었고, 원인이 되는 병변을 알 수 없었다. 결론: Tc-99m DISIDA 신티그라피에서 간 실질에 분절형 배설지연을 보이는 소견은 분절형 간내 담관폐쇄 진단에 높은 양성 예측도를 가진다. Tc-99m DISIDA 신티그라피는 특히 US나 CT가 정상인 경우에 분절형 담관폐쇄 진단에 선별검사로서 이용되어질 수 있을 것으로 생각된다. Tc-99m DISIDA 신티그라피의 분절형 담도관쇄 진단에서의 진단적 가치에 대한 전향적인 연구가 요구된다.

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Segmental Artery Injury Following Percutaneous Vertebroplasty Using Extrapedicular Approach

  • Heo, Dong-Hwa;Cho, Yong-Jun
    • Journal of Korean Neurosurgical Society
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    • 제49권2호
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    • pp.131-133
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    • 2011
  • We performed a percutaneous vertebroplasty at the compressed L2 vertebral body of a 73-year-old female using a left-sided unilateral extrapedicular approach. She complained severe radiating pain and a tingling sensation in her left leg two hours after the vertebroplasty. Spinal computed tomographic scan showed a large retroperitoneal hematoma, and a subsequent spinal angiography revealed a left L2 segmental artery injury. Bleeding was successfully controlled by endovascular embolization. Recently, extrapedicular approaches have been attempted, allowing for the avoidance of facet and pedicle injury with only a unilateral approach. With this approach, however, the needle punctures the vertebral body directly. Therefore, this procedure carries the potential risk of a spinal segmental artery.

Huge Psoas Muscle Hematoma due to Lumbar Segmental Vessel Injury Following Percutaneous Endoscopic Lumbar Discectomy

  • Kim, Hyeun-Sung;Ju, Chang-Il;Kim, Seok-Won;Kim, Jong-Gue
    • Journal of Korean Neurosurgical Society
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    • 제45권3호
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    • pp.192-195
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    • 2009
  • We present a case of an acute psoas muscle hematoma following percutaneous endoscopic lumbar discectomy. A 60-year-old female who presented with far lateral lumbar disc herniation underwent endoscopic discectomy on the right side at the L4-5 level. On the second postoperative day, the patient complained of severe right flank and leg pain and her blood pressure decreased. A computed tomography scan showed a large acute psoas muscle hematoma at right L4-5 level. The patient was transfused with packed red blood cells and placed at absolute bed rest. After observing the patient in intensive care, the severe flank and leg pain subsided, but the mild back pain persisted. Although percutaneous endoscopic lumbar discectomy is an effective minimally invasive surgical technique for the treatment of lumbar disc herniation, this case highlights the inherent risks of acute lumbar segmental vessel injury.

Computer Simulation Surgery for Mandibular Reconstruction Using a Fibular Osteotomy Guide

  • Jeong, Woo Shik;Choi, Jong Woo;Choi, Seung Ho
    • Archives of Plastic Surgery
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    • 제41권5호
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    • pp.584-587
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    • 2014
  • In the present study, a fibular osteotomy guide based on a computer simulation was applied to a patient who had undergone mandibular segmental ostectomy due to oncological complications. This patient was a 68-year-old woman who presented to our department with a biopsy-proven squamous cell carcinoma on her left gingival area. This lesion had destroyed the cortical bony structure, and the patient showed attenuation of her soft tissue along the inferior alveolar nerve, indicating perineural spread of the tumor. Prior to surgery, a three-dimensional computed tomography scan of the facial and fibular bones was performed. We then created a virtual computer simulation of the mandibular segmental defect through which we segmented the fibular to reconstruct the proper angulation in the original mandible. Approximately 2-cm segments were created on the basis of this simulation and applied to the virtually simulated mandibular segmental defect. Thus, we obtained a virtual model of the ideal mandibular reconstruction for this patient with a fibular free flap. We could then use this computer simulation for the subsequent surgery and minimize the bony gaps between the multiple fibular bony segments.

A comparison of fixation methods using three-dimensional finite element analysis following anterior segmental osteotomy

  • Yun, Kyoung In;Park, Min-Kyu;Park, Myung-Kyun;Park, Je Uk
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제38권6호
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    • pp.332-336
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    • 2012
  • Objectives: This study sought to evaluate fixation methods and determine the best method for the postoperative stabilization of maxillary osteotomy. For our analysis we performed a three-dimensional finite element analysis of stress distribution on the plate, screw, and surrounding bone, as well as displacement onto the plate. Materials and Methods: We generated a model using synthetic skull scan data; an initital surface model was changed to a solid model using software. Modified anterior segmental osteotomy (using Park's method) was made using the program, and four different types of fixation methods were used. An anterior load of 100 N was applied on the palatal surface of two central incisors. Results: The Type 1 (L-shaped) fixation method gave stresses of 187.8 MPa at the plate, 45.8 MPa at the screw, and 15.4 MPa at the bone around the plate. The Type 2 (I-shaped) fixation method gave stresses of 186.6 MPa at the plate, 75.7 MPa at the screw, and 13.8 MPa at the bone around the plate. The Type 3 (inverted L-shaped) fixation method gave stresses of 28.6 MPa at the plate, 29.9 MPa at the screw, and 15.3 MPa at the bone around the plate. The Type 4 (I-shaped) fixation method gave stresses of 34.8 MPa at the plate, 36.9 MPa at the screw, and 14.9 MPa at the bone around the plate. The deflection of the plates for the four fixation methods was 0.014 mm, 0.022 mm, 0.017 mm, and 0.018 mm, respectively. Conclusion: The Type 3 (inverted L-shaped) fixation method offers more stability than the other fixation methods. We therefore recommend this method for the postoperative stabilization of maxillary osteotomy.

출혈성 메켈게실의 진단 및 치료 (Diagnosis and Treatment of Bleeding Meckel's Diverticulum)

  • 허영수;김범별;윤정훈;곽동민
    • Advances in pediatric surgery
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    • 제7권1호
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    • pp.42-45
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    • 2001
  • The major complications of Meckel's diverticulum (MD) are bleeding, intestinal obstruction, infection, umbilical fistula and perforation. Although the relative incidences vary between authors, bleeding is the most common complication in children. The aim of our study is to show the symptomatic guideline for the diagnosis of the bleeding MD. Eight cases with bleeding MD which were operated upon at the department of Pediatric Surgery, Yeungnam University Hospital from April 1985 to April 2001 were reviewed. Half of the patients were under 2 years of age and all patient s we re male. All patients were preoperatively diagnosed by previous history of intestinal bleeding (melena, hematochezia) and 99mTc pertechnetate MD scan. Segmental resection and end-to-end anastomosis was performed in 6 patients and diverticulectomy in 2 patients. Heterotropic gastric mucosa was found in 6 patients. Postoperative complication was not observed in any cases. In conclusion, in any male children with obscure intestinal bleeding, especially less than 2 years of age, bleeding MD must be suspected. It seems to us that 99mTc pertechnetate MD scan is a useful tool to diagnose bleeding MD.

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후천성 폐 동정맥루 -1례 보고- (Acquired Pulmonary Arteriovenous Fistula -A Case Report-)

  • 김남혁
    • Journal of Chest Surgery
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    • 제28권5호
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    • pp.495-498
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    • 1995
  • Pulmonary arteriovenous fistula can be either congenital or acquired. The vast majority are congenital, and about 60% have been associated with hereditary hemorrhagic telangiectasia [Rendu-Osler-Weber disease . Secondary or acquired pulmonary arteriovenous fistula occurs with trauma, schistosomiasis, long-standing hepatic cirrhosis, metastatic carcinoma, and actinomycosis. Pulmonary hemorrhage secondary to acquired pulmonary arteriovenous fistula is a rare event associated with mortality. We have experienced 64 year-old female patient with the hemoptysis secondary to acquired pulmonary arteriovenous fistula due to the infection of pulmonary parasite. The chest PA and CT scan was showed calcified nodule to the distal portion of lateral segmental bronchus of RML. The bronchial angiogram was demonstrated slightly hypertrophied bronchial artery supplying RML bronchus and the presence of hypervascularization around the calcified nodule, rapid A-V shunting is noted by fluoroscopy. The patient was successfully treated by the right middle lobectomy.

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