• 제목/요약/키워드: Reconstruction plate

검색결과 187건 처리시간 0.027초

부채살 SPECT 데이터를 위한 정칙화된 기댓값 최대화 재구성기법 개발 (Development of Regularized Expectation Maximization Algorithms for Fan-Beam SPECT Data)

  • 김수미;이재성;이수진;김경민;이동수
    • 대한핵의학회지
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    • 제39권6호
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    • pp.464-472
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    • 2005
  • 목적: 부채살 단일광자단층촬영(SPECT)은 공간분해능과 민감도를 개선하는 것으로 알려져 있다. 보다 정확한 영상을 얻고 인체에 대한 SPECT의 영상화 과정을 정확하게 묘사하기 위하여 평행 데이터로 재배열하는 과정 없이 직접 부채살 데이터를 이용하여 재구성하는 알고리즘이 필요하다. 본 연구는 다양한 부채살 재구성 알고리즘을 구현하였고 각 방법의 성능을 비교하였다. 대상 및 방법: 선추적법을 적용하여 부채살 투사기와 이로부터 얻은 데이터를 직접 재구성할 수 있는 FBP, EM, OS-EM과 MAP-EM OSL 알고리즘을 구현하였다. OSL 알고리즘의 경우에는 membrane과 thin plate prior를 사용하였다. 직접 부채살 데이터를 재구성하는 방법의 성능을 평가하기 위해 양방향 최근접 이웃, 양방향 1차와 양방향 3차 보간법을 사용하여 재배열된 평행 데이터를 얻었고 이 데이터를 기존의 평행 데이터에 대한 EM 알고리즘을 사용하여 재구성하였다. Hoffman 두뇌와 Shepp/Logan 팬텀으로부터 얻은 잡음 없는 데이터와 잡음 있는 데이터는 각 방법으로 재구성하였으며 퍼센트 오차를 계산하여 각 재구성된 영상을 비교하였다. 결과: Thin-plate 사전 분포함수를 사용한 OSL 방법이 가장 낮은 오차를 가지며 잡음으로 인한 결과 영상의 불안정성을 효과적으로 제어함을 확인할 수 있었다. 부채살 데이터를 평행 데이터로 재배열시 양방향 1차 보간법이 정확성과 계산 시간 측면에서 가장 효율적인 방법임을 확인하였다. 재배열된 평행 데이터의 EM결과에 비해 직접 부채살 데이터를 재구성하여 얻은 결과영상이 더 정확하게 재구성되었다. 결론: 본 연구에서는 평행 데이터로 재배열한 경우에 비하여 보다 정확한 영상을 재구성하는 직접 부채살 재구성 알고리즘을 구현하였으며 이는 정량적으로 월등히 개선된 결과를 제공함을 확인하였다.

Clinical and Radiologic Outcomes of Acute Acromioclavicular Joint Dislocation: Comparison of Kirschner's Wire Transfixation and Locking Hook Plate Fixation

  • Rhee, Yong Girl;Park, Jung Gwan;Cho, Nam Su;Song, Wook Jae
    • Clinics in Shoulder and Elbow
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    • 제17권4호
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    • pp.159-165
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    • 2014
  • Background: Kirschner's wire (K-wire) transfixation and locking hook plate fixation techniques are widely used in the treatment of acute acromioclavicular joint (ACJ) dislocation. The purpose of this study was to compare the clinical and radiologic outcomes between K-wires transfixation and a locking hook plate fixation technique. Methods: Seventy-seven patients with acute ACJ dislocation managed with K-wire (56 shoulders) and locking hook plate (21 shoulders) were enrolled for this study. The mean follow-up period was 61 months. Results: At the last follow-up, the shoulder rating scale of the University of California at Los Angeles (UCLA) was higher in patients treated with locking hook plate than with K-wires ($33.2{\pm}2.7$ vs. $31.3{\pm}3.4$, p=0.009). In radiologic assessments, coracoclavicular distance (CCD) (7.9 mm vs. 7.7 mm, p=0.269) and acromioclavicular distance (ACD) (3.0 mm vs. 1.9 mm, p=0.082) were not statistically different from contralateral unaffected shoulder in locking hook plate fixation group, but acromioclavicular interval (ACI) was significant difference. However, there were significant differences in ACI, CCD, and ACD in K-wire fixation group (p<0.001). Eleven complications (20%) occurred in K-wire transfixation group and 2 subacromial erosions on computed tomography scan occurred in locking hook plate fixation group. Conclusions: ACJ stabilization was achieved in acute ACJ dislocations treated with K-wires or locking hook plates. Locking hook plate can provide higher UCLA shoulder score than K-wire and maintain CCD, and ACD without ligament reconstruction. K-wire transfixation technique resulted in a higher complication rate than locking hook plate.

Titanium Plate Fixation for Sternal Dehiscence in Major Cardiac Surgery

  • Kim, Wan Kee;Kim, Joon Bum;Kim, Gwan Sic;Jung, Sung-Ho;Choo, Suk Jung;Chung, Cheol Hyun;Lee, Jae Won
    • Journal of Chest Surgery
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    • 제46권4호
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    • pp.279-284
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    • 2013
  • Background: Sternal dehiscence is one of the most troublesome complications following cardiac surgery. Treatment failure and consequent lethal outcomes are very common. The aim of this study was to evaluate titanium plate fixation as a treatment for sternal dehiscence following major cardiac surgery. Materials and Methods: Between 2010 and 2012, 17 patients underwent sternal reconstruction using horizontal titanium plating for the treatment of post-cardiac-surgery sternal dehiscence. The plates were cut and shaped, and then were fixed to corresponding costal segments using 2-3 titanium screws per each side. Results: The median age of our patients was 66 years (range, 50 to 78 years) and 9 were female. Indications for sternal reconstruction included aseptic sternal dehiscence in 3 patients and osteomyelitis in 14 patients including 6 patients who were diagnosed with mediastinitis. During the operation, sternal resection and autologous flap interposition were combined in 11 patients. One patient died due to sepsis. Two patients required additional soft tissue wound revisions. Another patient presented with a tuberculous wound infection which was resolved using anti-tuberculosis medications. The postoperative course was uncomplicated in the other 13 patients. Conclusion: Titanium plate fixation that combines appropriate debridement and flap interposition is very effective for the treatment of sternal dehiscence following major cardiac surgery.

Switching Antibiotics Production On and Off in Actinomycetes by an IclR Family Transcriptional Regulator from Streptomyces peucetius ATCC 27952

  • Chaudhary, Amit Kumar;Singh, Bijay;Maharjan, Sushila;Jha, Amit Kumar;Kim, Byung-Gee;Sohng, Jae Kyung
    • Journal of Microbiology and Biotechnology
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    • 제24권8호
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    • pp.1065-1072
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    • 2014
  • Doxorubicin, produced by Streptomyces peucetius ATCC 27952, is tightly regulated by dnrO, dnrN, and dnrI regulators. Genome mining of S. peucetius revealed the presence of the IclR (doxR) type family of transcription regulator mediating the signal-dependent expression of operons at the nonribosomal peptide synthetase gene cluster. Overexpression of doxR in native strain strongly repressed the drug production. Furthermore, it also had a negative effect on the regulatory system of doxorubicin, wherein the transcript of dnrI was reduced to the maximum level in comparision with the other two. Interestingly, the overexpression of the same gene also had strong inhibitory effects on the production of actinorhodin (blue pigment) and undecylprodigiosin (red pigment) in Streptomyces coelicolor M145, herboxidiene production in Streptomyces chromofuscus ATCC 49982, and spinosyn production in Saccharopolyspora spinosa NRRL 18395, respectively. Moreover, DoxR exhibited pleiotropic effects on the production of blue and red pigments in S. coelicolor when grown in different agar media, wherein the production of blue pigment was inhibited in R2YE medium and the red pigment was inhibited in YEME medium. However, the production of both blue and red pigments from S. coelicolor harboring doxR was halted in ISP2 medium, whereas S. coelicolor produced both pigmented antibiotics in the same plate. These consequences demonstrate that the on and off production of these antibiotics was not due to salt stress or media compositions, but was selectively controlled in actinomycetes.

골연부 종양에서 저온 열처리한 자가골을 이용한 재건술 (Autogenous Low Heat Treated Bone Graft for Bone Reconstruction in Bone and Soft Tissue Tumors)

  • 전대근;이종석;김석준;조완형;곽봉준;이수용
    • 대한골관절종양학회지
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    • 제4권2호
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    • pp.81-87
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    • 1998
  • Although autoclaved autogenous bone reconstruction is one of the established procedures, it may have some problems in bone regeneration and mechanical property. The purpose of this study is to evaluate the efficacy of more biologic and anatomical reconstruction where allograft is not readily available. From Aug.1991 to Feb. 1996 the authors analyzed 32 cases of reconstruction with autogenous low heat treated bone. Autogenous graft sites were humerus 4, tibia 4, pelvis 9, and 15 femur. Average follow-up period was 23(range;12-51) months. There were 49 graft-host junctional sites. Diaphysis was 22, metaphysis 10, and flat bone 17. Average duration of healing for the 38 united sites was 7 months. Average union time for each anatomical area 8 months in 19 diaphysis, 12 months in 7 metaphysis, and 12.7 months in 12 flat bone(pelvis). Eleven nonunion sites consisted of 3 diaphysis(3/22), 3 metaphysis(3/10), and 5 flat bone(5/17). Complications other than nonunion were local recurrence(4), bone resorption(3), graft fracture(2), osteomyelitis(1), metal failure(2), and wound infection(1). Initial bone quality and stable fixation technique was important for union rate. Plate and screw is a good method for diaphyseal lesion. Metaphyseal and flat bone are weak area for rigid fixation and one stage augmentation with iliac bone graft can be a salvage procedure.

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구순구개열 환자에서 골신장술을 이용한 전상악골의 재건 (Premaxillary Reconstruction by Distraction Osteogenesis for Cleft Lip/Palate)

  • 김기호;정영수;최진환;이상휘;유형석;손병화;이충국
    • 대한구순구개열학회지
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    • 제9권2호
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    • pp.63-70
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    • 2006
  • Patients with cleft lip and palate usually present midfacial depression and anterior cross-bite. This dentofacial deformity has been believed due to the undergrowth of maxilla and/or the collapse of premaxilla. But, in the case that the collapsed premaxilla exists only, the reconstruction of the premaxilla has to be required for the correction of that deformity. These cases show the surgical treatment of midfacial depression and anterior cross-bite in the cleft lip and palate. After the careful diagnosis for the collapse of premaxilla, the reconstruction using distraction osteogenesis was done successfully. As a result, the anterior overbite / overjet, and facial esthetics were improved remarkably, and the occlusion was also recovered to normal state. In conclusion, the premaxillary reconstruction by distraction osteogenesis in cleft lip and palate patients is a good treatment method based on the pathophysiology.

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Surgical Reconstruction Using a Flanged Mesh Cage without Plating for Cervical Spondylotic Myelopathy and a Symptomatic Ossified Posterior Longitudinal Ligament

  • Kang, Jung Hoon;Im, Soo-Bin;Yang, Sang-Mi;Chung, Moonyoung;Jeong, Je Hoon;Kim, Bum-Tae;Hwang, Sun-Chul;Shin, Dong-Seong;Park, Jong-Hyun
    • Journal of Korean Neurosurgical Society
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    • 제62권6호
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    • pp.671-680
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    • 2019
  • Objective : We introduce innovative method of cervical column reconstruction and performed the reconstruction with a flanged titanium mesh cage (TMC) instead of a plate after anterior corpectomy for cervical spondylotic myelopathy (CSM) and an ossified posterior longitudinal ligament (OPLL). Methods : Fifty patients with CSM or OPLL who underwent anterior cervical reconstruction with a flanged TMC were investigated retrospectively. Odom's criteria were used to assess the clinical outcomes. The radiographic evaluation included TMC subsidence, fusion status, and interbody height. Thirty-eight patients underwent single-level and 12 patients underwent two-level corpectomy with a mean follow-up period of 16.8 months. Results : In all, 19 patients (38%) had excellent outcomes and 25 patients (50%) had good outcomes. Two patients (4%) in whom C5 palsy occurred were categorized as poor. The fusion rate at the last follow-up was 98%, and the severe subsidence rate was 34%. No differences in subsidence were observed among Odom's criteria or between the single-level and two-level corpectomy groups. Conclusion : The satisfactory outcomes in this study indicate that the flanged TMC is an effective graft for cervical reconstruction.

외상성 역동적 무지 내반증(1예 보고) (Traumatic Dynamic Hallux Varus (A Case Report))

  • 임수재;이영구;김진수;박찬호;강희경
    • 대한족부족관절학회지
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    • 제13권2호
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    • pp.193-196
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    • 2009
  • The first metatarsophalangeal joint injury is common in professional soldiers and athletes. But this was rarely reported. A professional soldier has varus instability in the first metatarsophalangeal joint due to hyperextension. In the MR Imaging, weavy appearance in lateral collateral ligament and high signal change in plantar plate was shown. So he has surgical treatment using reconstructive procedure. At first, $4^{th}$ extensor digitorum longus tendon was splitted longitudinally and harvested, second triangular shape reconstruction on lateral joint line was done using harvested tendon. One year later, fifteen degrees was limited compared with intact side. Reconstruction using $4^{th}$ extensor digitorum longus tendon in traumatic dynamic hallux varus was good method.

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하악골 정중부에서 채취한 피질해면골블록을 이용한 구내 골결손부의 재건: 증례보고 (RECONSTRUCTION OF INTRAORAL JAW DEFECTS WITH CORTICOCANCELLOUS BLOCK OF MANDIBULAR SYMPHYSIS)

  • 김영균;김현태;조창욱
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제26권6호
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    • pp.666-671
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    • 2000
  • Objectives: This study evaluated the availability of mandibular symphysis corticocancellous block grafts in patients treated for reconstruction of intraoral jaw defects. Materials & Methods: 8 patients with mandibular and maxillary bony defects were treated with corticocancellous block of symphysis. The types of defects included 4 pathologic jaw defects and 4 vertical and/or horizontal alveolar deficiencies. The age ranged from 13 to 45 years. Additional treatments such as plate fixation, alloplastic bony substitutes, and/or barrier membrane application were perfomred. They were evaluated for complications and healing of defects. Follow-up period ranged from 6 to 15 months. Results: 2 patients experienced complications such as wound dehiscence and mild resorption of exposed bone. None of the patients needed secondary operation. Paresthesia of lip, chin, and teeth were recovered completely by 6 months postoperatively. Reconstructed wound showed favorable healing and bony consolidation. Conclusion: Corticocancellous block of mandibular symphysis can be used for the reconstruction of a variety of intraoral local jaw defects selectively. Advantages were easy fixation of graft, possibility of restoration of original alveolar contour, and decreased donor site morbidity.

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양측성 치조열 환자의 tongue flap reconstruction(Y형 전기저 설피판) 후에 2차성 치조골 재건술의 예후 (Prognosis of secondary alveolar bone reconstruction after tongue flap reconstruction ( V-shaped anterior based ) of bilateral alveolar cleft)

  • 김명진;이종호;이지호;강나라;팽준영;명훈;황순정;서병무;최진영;정필훈
    • 대한구순구개열학회:학술대회논문집
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    • 대한구순구개열학회 2003년도 종합학술대회
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    • pp.39-39
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    • 2003
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