문서 경계와 3차원 재구성에 기반한 문서 이미지 평판화

학위논문(석사) -- 서울대학교대학원 : 자연과학대학 수리과학부, 2022. 8. 현동훈.In recent days, most of the scanned images are obtained from mobile devices such as cameras, smartphones, and tablets rather than traditional flatbed scanners. Contrary to the scanning process of the traditional scanners, capturing process of mobile devices might be accompanied by distortions in various forms such as perspective distortion, fold distortion, and page curls. In this thesis, we propose robust dewarping methods which correct such distortions based on the document boundary and 3D reconstruction. In the first method, we construct a curvilinear grid on the document image using the document boundary and reconstruct the document surface in the three dimensional space. Then we rectify the image using a family of local homographies computed from the reconstructed document surface. Although some of the steps of the proposed method have been proposed separately in other research, our approach exploited and combined their advantages to propose a robust dewarping process in addition to improving the stability in the overall process. Moreover, we refined the process by correcting the distorted text region boundary and developed this process into an independent dewarping method which is concise, straight-forward, and robust while still producing a well-rectified document image.최근에는 대부분의 스캔된 이미지들이 전통적인 평판스캐너가 아닌 카메라, 스마트폰, 태블릿 PC 등의 휴대기기들로부터 얻어진다. 이전 스캐너들의 스캐닝 과정과는 다르게 휴대기기들을 이용한 이미지 캡쳐링 과정은 원근왜곡, 종이의 접힘으로 인한 왜곡, 그리고 종이의 휘어짐으로 인한 왜곡 등 다양한 왜곡들을 수반할 수 있다. 이 논문에서는 이러한 왜곡들을 제거할 수 있는 문서 경계와 3차원 재구성에 기반한 강력한 디워핑 방법을 제안하고자 한다. 첫번째 방법에서는, 문서 경계를 이용하여 문서 이미지 위에 곡선으로 이루어진 그리드를 만들고, 3차원 공간 상의 문서 곡면을 재구성한다. 그리고 재구성된 문서 곡면으로부터 계산된 국소적 호모그래피들을 이용하여 이미지를 수정한다. 우리가 제안하는 방법의 몇몇 단계는 다른 연구에서 개별적으로 사용된 경우도 있지만, 우리는 전체적인 과정에서 안정성을 높이는 동시에 각 방법의 장점들을 이용하고 조합하여 강력한 디워핑 방법을 제안한다. 이에 더하여, 우리는 왜곡된 텍스트 영역의 경계를 수정하여 전체적인 과정을 보완하였고, 이 절차를 간결하고, 직관적이며, 강력하면서도 좋은 결과를 내는 독립적인 디워핑 방법으로 개발하였다.1. Introduction 1 2. Review on Camera Geometry 6 2.1. Basic Camera Model 6 2.2. 3D Reconstruction Problem 8 3. Related Works 10 3.1. Dewarping Methods based on the Text-lines 10 3.2. Dewarping Methods based on the Document Boundary 11 3.3. Dewarping Methods based on the Grid Construction 12 3.4. Dewarping Methods based on the Document Surface Model in 3D Space 13 4. Document Image Dewarping based on the Document Boundary and 3D Reconstruction 15 4.1. Input Document Image Processing 17 4.1.1. Binarization of the Input Document Image 17 4.1.2. Perspective Distortion Removal using the Document Boundary 19 4.2. Grid Construction on the Document Image 21 4.3. 3D Reconstruction of the Document Surface 23 4.3.1. Geometric Model 23 4.3.2. Normalization of the Grid Corners 24 4.3.3. 3D Reconstruction of the Document Surface 26 4.4. Rectification of the Document Image under a Family of Local Homographies 27 4.5. Global Rectification of the Document Image 29 5. Document Image Dewarping by Straightening Document Boundary Curves 33 6. Conclusion 37 Appendix A. 38 A.1. 4-point Algorithm 38 A.2. Optimization of the Cost Function 40 Bibliography 42 Abstract (in Korean) 47 Acknowledgement (in Korean) 48석

Comparison between tension-free vaginal tape (TVT) and transobturator tape (TOT) with concomitant surgery for pelvic organ prolapse

Objective: To compare tension-free vaginal tape (TVT) and transobturator tape (TOT) for surgical treatment of stress urinary incontinence (SUI) associated with pelvic organ prolapse (POP). Methods: Two hundred seventy eight consecutive patients affected by SUI associated with POP more than stage II were included in this retrospective study. Cure rate and postoperative complications such as hemoglobin difference between preoperative and postoperative period, vaginal hematoma, bladder and bowel injury, vaginal mesh erosion, urinary retention, de novo urgency, urinary tract infection were compared. Student`s t-test and chi square test were used for statistical analysis. A P-value below 0.05 was considered statistically significant. Results: The number of patients underwent TVT was 145 and TOT was 133. All patients were followed up for more than 12 months. The general characteristics of patients showed no significant difference between the two groups. There was no difference between two groups in cure rate. However, hemoglobin difference (TVT, 2.91±0.93 g/dL; TOT, 1.53±0.77 g/dL; P=0.04) was higher in TVT group than TOT group and urinary retention within 1 month (TVT, 35.17%; TOT, 21.05; P=0.02), and urinary tract infection (TVT, 11.72%; TOT, 3.75%; P=0.02) more frequently appeared in TVT group than TOT group. Other postoperative complications such as vaginal hematoma (TVT, 6.89%; TOT, 6.76%; P=0.86), bowel injury (TVT, 0%; TOT, 1.5%; P=0.64), vaginal mesh erosion (TVT, 7.58%; TOT, 4.51%; P=0.47), urinary retention after 1 month (TVT, 2.76%; TOT, 3.00%; P=0.35), de novo urgency (TVT 7.58%, TOT: 6.01%, P=0.48) were not different between two groups. Conclusion: Both procedures appear to be equally effective in the surgical treatment of SUI associated with POP. However, TOT seems to be a more safe procedure in postoperative complicationsope

MicroRNA 30d와 181a에 의한 자궁엉치인대 내 HOXA11 발현조절 및 골반장기탈출증 환자에서의 과발현 양상 규명

Dept. of Medicine/박사Objectives: The balance between the synthesis and degradation of collagen is important in maintaining the structural integrity and tensile strength of pelvic supportive connective tissues. Homeobox A11 (HOXA11) is a key transcriptional factor that regulates collagen metabolism, and its expression is decreased in the uterosacral ligaments (USLs) of women with pelvic organ prolapse (POP). The aim of the present study was to identify specific microRNAs (miRNAs) involved in the regulation of HOXA11 expression in the USLs and to define their biologically functional effects.Methods: miRNA expression was assessed in the USLs of women with and without POP using microarray and quantitative real-time polymerase chain reaction (RT-PCR) analysis. To determine the role of selected miRNAs in the regulation of HOXA11, 293T cells were transfected with miR mimic, anti-miR or negative controls. Then, quantitative RT-PCR, Western blotting and luciferase reporter assays were performed.Results: MiR-30d and miR-181a were overexpressed in the USLs of women with POP, and the expression of both miRNAs was inversely correlated with HOXA11 mRNA expression. In cultured 293T cells, the overexpression of miR-30d/181a suppressed HOXA11 mRNA and protein levels, whereas knockdown of these miRNAs enhanced HOXA11 levels. Cotransfection of a luciferase reporter plasmid containing the 3′-UTR of HOXA11 with miR-30d/181a mimics resulted in decreased relative luciferase activity. Conversely, cotransfection with anti-miR-30d/181a increased the relative luciferase activity.Conclusion: These results indicate that both miR-30d and miR-181a directly downregulate HOXA11 expression at the posttranscriptional level and that the decreased HOXA11 expression in the USLs of women with POP might be caused by the aberrant expression of these miRNAs. Therefore, therapeutic approaches aimed at decreasing these miRNAs might be useful for restoring the altered collagen metabolism and homeostasis in the USLs that leads to POP.ope

COL3A1 엑손 31의 다형성과 골반장기 탈출증간의 연관성

Dept. of Medicine/석사[한글]목적: 골반장기 탈출증은 높은 발생빈도에도 불구하고 병태생리가 현재까지 충분히 밝혀져 있지 않다. 여러 생화학적 연구들에서 제 3형 콜라겐 증가로 인해 제 1형 대 제 3형 콜라겐의 비가 감소되어 있는 것이 관찰되었으나 일부 이와 상충된 연구결과를 보여주는 연구들도 있다. 이는 연구대상 군의 이질성에 기인할 수 있다. 또한 이러한 생화학적 연구는 관찰 소견이 골반장기 탈출증의 원인인지 결과인지 구분하기 어려운 제한점이 있다. 최근 한 연구에서 근긴장저하 승모판/승모판 탈출증을 가진 환자들이 대조군에 비해 COL3A1 엑손 31에서 보다 높은 빈도의 GG 유전자형을 갖고 있는 것이 관찰되었다. 본 연구의 목적은 아미노산 서열 570번 위치에서 (guanine 대신 adenine으로의 단일 염기 치환을 통해) alanine을 threonine으로 바꾸는 COL3A1 엑손 31의 다형성과 골반장기 탈출증 간의 연관성에 대해 알아보고자 함이었다. 연구대상 및 방법: 50에서 65세 사이의 호르몬 대체요법을 받고 있지 않는 총 72명의 폐경 여성을 대상으로 본 연구를 시행하였다. 환자 군은 2기 이상의 골반장기 탈출증으로 진단 받은 36명의 여성들로 구성되었고, 대조 군은 골반장기 탈출증 0기 또는 1기의, 환자 군과 나이 및 질식 분만력을 짝짓기한 36명의 여성들로 구성되었다. 이들 환자들을 대상으로 말초 혈액 백혈구로부터 게놈 DNA를 추출하였다. COL3A1의 엑손 31의 다형성은 restriction fragment length polymorphism (RFLP) 방법인 Alu I RFLP를 통해 조사하였다. 결과: G 대립인자 (allele) 빈도는 골반장기 탈출증 환자 군에서 대조 군에 비해 더 높았으며 (0.8 대 0.6, p=0.002), 유전자형 (genotype) 역시 두 군 간에 유의한 차이를 보였다 (p=0.001). A 대립인자를 가진 여성에 비해 G 대립인자를 가진 여성은 골반장기 탈출증에 대한 위험도가 3.2배 높았으며 (95% 신뢰구간 1.4-7.3), GG 유전자형을 가진 여성은 다른 유전자형을 가진 여성에 비해 골반장기 탈출증에 대한 위험도가 4.3배 높았다 (95% 신뢰구간 1.4-13.3). 결론: 본 연구는 COL3A1 엑손 31 다형성이 골반장기 탈출증 발생 위험 증가와 연관이 있음을 보여주고 있다. [영문]Objective: Despite the high incidence of pelvic organ prolapse (POP), its pathogenesis is still poorly understood. Some biochemical studies have demonstrated decreased ratio of type I to III collagen due to increased expression of type III collagen in the vagina and its supportive structures of women with POP, but others have shown conflicting results. This may be due to the heterogeneity of the study population. Moreover, these studies have the limitation that it is impossible to distinguish whether the finding is a cause or an effect of POP. A recent study found that patients with floppy mitral valve (FMV)/mitral valve prolapse(MVP) had higher frequency of COL3A1 exon 31 GG genotype than the control group. The aim of this study was to investigate whether the polymorphism of COL3A1 exon 31 (a single base substitution from Guanine to Adenine at +2209), resulting in the replacement of alanine with threonine at the 570th amino acid of COL3A1, is associated with POP. Materials and Methods: A total number of 72 postmenopausal Korean women not taking hormonal replacement therapy, aged from 50 to 65 were enrolled in this study. The patient group consisted of 36 women diagnosed as POP of which stage was II or greater, irrespective of the presence of urodynamic stress incontinence. The control group consisted of 36 age- and vaginal parity-matched volunteers with pelvic organ prolapse-quantification stage 0 or I without urodynamic stress incontinence. The genomic DNA was extracted from peripheral blood leukocytes. The polymorphism of exon 31 of COL3A1 was typed by the restriction fragment length polymorphism (RFLP) method, Alu I RFLP and confirmed by direct sequencing. Results: A significantly higher frequency in G allele was noted in patients with POP than in controls (0.8 vs. 0.6, p=0.002). A significant difference in the genotype was also noted (p=0.001). An odds ratio for POP in women with G allele was 3.2 (95% confidence interval 1.4-7.3) and in women with GG genotype 4.3 (95% confidence interval 1.4-13.3). Conclusion: This study shows that COL3A1 exon 31 polymorphism is associated with increased risk of POP.ope

Use of grafts in pelvic reconstructive surgery

There has been growing interest in the use of grafts in pelvic reconstructive surgery. This article will address available graft materials and assess their clinical efficacy and safety. We conducted a Pubmed MEDLINE literature search for full-length English text studies with follow-up periods of at least one year. There are many reports on synthetic and biological graft materials; the majority are not well-designed, have short-term follow-up, small sample sizes, and poor outcome assessment. The use of non-absorbable synthetic grafts may offer excellent anatomical cure rates. However, it is associated with a high incidence of graft-related complications, including healing abnormalities and adverse bladder, bowel, and sexual function effects. These complications can be decreased with absorbable synthetic meshes, but efficacy is lower compared to non-absorbable ones. There is insufficient evidence in favor of biological grafts. In conclusion, based on current knowledge, routine application of grafts in pelvic reconstruction is not recommended. It is preferred that graft utilization be individualized, with close monitoring for complications.ope

Surgical morbidity in patients with pelvic organ prolapse at various ages

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Concomitant pelvic reconstructive surgery and transobturator tape for stress urinary incontinence

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Preoperative maximum urethral closure pressure and valsalva leak point pressure as predictive parameters for midurethral sling

OBJECTIVE: To evaluate the efficacy of tension-free vaginal tape (TVT) and transobturator tape (TOT) according to urethral function based on a preoperative urodynamic study (UDS). STUDY DESIGN: Preoperative Valsalva leak point pressure (VLPP) and maximum urethral closure pressure (MUCP) were compared with the actual surgical outcome, and patients were followed for > 1 year. Student's t test, chi2 test, multiple regression analysis and receiver operating character curve analysis were used for statistical analysis. Of the 437 patients, 225 received TVT and 212 patients received TOT. RESULTS: Age, parity, body mass index, menopausal status, hormone replacement therapy and previous surgical history showed no significant difference between the groups. Advanced pelvic organ prolapse, concomitant hysterectomy and vault suspension were more common in the TOT group, whereas concomitant anterior colporrhaphy was more common in the TVT group. The treatment outcome of TVT was not associated with VLPP and MUCP. However, cutoff values of VLPP > or = 72.5 cm H2O and MUPC > or = 42 cm H2O were most predictive of successful surgical outcomes in TOT group, revealing a sensitivity of 95.7% and a positive predictive value of 98.4%. CONCLUSION: Preoperative MUCP and VLPP can predict the treatment outcome of TOT but not TVT.ope

The relationship between COL3A1 exon 31 polymorphism and pelvic organ prolapse.

PURPOSE: We investigated the role of COL3A1 exon 31 polymorphism (a single base substitution from guanine to adenine at +2092), resulting in the replacement of alanine with threonine at the 698th amino acid of COL3A1, in the pathogenesis of pelvic organ prolapse. MATERIALS AND METHODS: A total of 72 postmenopausal Korean women who were not on hormonal replacement therapy and who had a history of vaginal childbirth were enrolled in this study. The patient group consisted of 36 women diagnosed with stage II or greater pelvic organ prolapse irrespective of urodynamic stress incontinence. The control group consisted of 36 healthy volunteers with pelvic organ prolapse quantification system stage 0 or I disease without urodynamic stress incontinence. After extracting the genomic DNA from peripheral blood leukocytes the polymorphism of exon 31 of COL3A1 was typed by restriction fragment length polymorphism (Alu I restriction fragment length polymorphism) and confirmed by direct sequencing. RESULTS: Frequency of the G allele was significantly higher in patients with pelvic organ prolapse than in controls (0.8 vs 0.6, p = 0.002). In women with the G allele the OR for pelvic organ prolapse was 3.2 (95% CI 1.4-7.3). CONCLUSIONS: COL3A1 exon 31 polymorphism may have a role in determining the risk of pelvic organ prolapse in women with risk factors such as aging, vaginal childbirth and hypoestrogenism.ope

Changes in expression of fibulin-5 and lysyl oxidase-like 1 associated with pelvic organ prolapse.

OBJECTIVES: Pelvic organ prolapse is associated with defects in connective tissue including elastic fibers. The purpose of this study was to investigate expression of fibulin-5 and lysyl oxidase-like 1, which play an essential role in synthesis and assembly of elastic fibers in the uterosacral ligament, in samples taken from women with advanced pelvic organ prolapse compared with controls. STUDY DESIGN: Specimens were obtained prospectively during abdominal hysterectomy from 30 women with advanced pelvic organ prolapse and 30 controls matched to the study group for age and parity among postmenopausal women with benign gynecologic pathology. Expression levels of protein and mRNA of fibulin-5 and lysyl oxidase-like 1 in uterosacral ligaments were measured by Western blot analysis and real-time quantitative polymerase chain reactions. For statistical analyses, Student's t-test, chi-square test, Mann-Whitney U test, Fisher's exact test and Spearman's correlation were used. RESULTS: Significant decrease in the expression of mRNA of fibulin-5 was found in patients with prolapse (P-value=0.042; 0.743+/-0.229 and 1.061+/-0.537). The expression of mRNA of lysyl oxidase-like 1 was increased in the patient group (P-value=0.017; 4.099+/-2.832 and 1.816+/-1.602). Similar results were shown in Western blot analysis. Differences in expression of fibulin-5 and lysyl oxidase-like 1 were noted according to stage of prolapse (P-value=0.037 and 0.009). CONCLUSIONS: There was decreased expression of fibulin-5 and increased expression of lysyl oxidase-like 1 in uterosacral ligaments in patients with pelvic organ prolapse, which suggests the possibility of defects in elastin synthesisope