• Imaging Science in Dentistry
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• v.44 no.3
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• pp.199-205
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• 2014

Purpose: This study aimed to investigate the effect of changing the kilovoltage peak (kVp) on the radiographic assessment of dental caries. Materials and Methods: Seventy-five extracted posterior teeth with proximal caries or apparently sound proximal surfaces were radiographed with conventional E-speed films and a photostimulable phosphor system using 60 kVp and 70 kVp for the caries assessment. The images were evaluated by three oral radiologists and compared with the results of the stereomicroscope analysis. Results: No statistically significant difference was found between 60 kVp and 70 kVp for the caries detection, determination of caries extension into dentin, and caries severity in either the conventional or the digital images. Good to very good inter-observer and intra-observer agreements were found for both kilovoltage values on the conventional and digital images. Conclusion: Changing the kilovoltage between 60 kVp and 70 kVp had no obvious effect on the detection of proximal caries or determination of its extension or severity.

• Journal of Korean Neurosurgical Society
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• v.53 no.3
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• pp.150-154
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• 2013

Objective : To evaluate the effect of electromagnetic (EM) navigation system on ventriculoperitoneal (VP) shunt failure rate through comparing the result of standard shunt placement. Methods : All patients undergoing VP shunt from October 2007 to September 2010 were included in this retrospective study. The first group received shunt surgery using EM navigation. The second group had catheters inserted using manual method with anatomical landmark. The relationship between proximal catheter position and shunt revision rate was evaluated using postoperative computed tomography by a 3-point scale. 1) Grade I; optimal position free-floating in cerebrospinal fluid, 2) Grade II; touching choroid or ventricular wall, 3) Grade III; tip within parenchyma. Results : A total of 72 patients were participated, 27 with EM navigated shunts and 45 with standard shunts. Grade I was found in 25 patients from group 1 and 32 patients from group 2. Only 2 patients without use of navigation belonged to grade III. Proximal obstruction took place 7% in grade I, 15% in grade II and 100% in grade III. Shunt revision occurred in 11% of group 1 and 31% of group 2. Compared in terms of proximal catheter position, there was growing trend of revision rate according to increase of grade on each group. Although infection rate was similar between both groups, the result had no statistical meaning (p=0.905, chi-square test). Conclusion : The use of EM navigation in routine shunt surgery can eliminate poor shunt placement resulting in a dramatic reduction in failure rates.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.553-556
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• 2013

Background: This study was designed to examine changing trends in localization of gastric cancer in Turkey in recent years. Materials and Methods: A total of 796 adult patients with newly diagnosed, histologically proven adenocarcinomas, treated and followed up at our oncology center between 2000-2011, were examined retrospectively. In all cases tumor localization were identified and recorded with clinicopathological features. Results: The median age was 58 with a range between 22-90 for the 552 men and 244 women. Median follow up was 12 months (1-276) and median overall survival was also 12 months (11.5-12.4). There was a trend for a change in tumor localization from distal to proximal. Survival of patients was low with advanced T and N stage tumours. Positive surgical margins, lymphovascular invasion, perineural invasion, cardioesophageal localization were predisposition factors for metastatic disease in gastric cancer. There was no relation between age or sex and histopathological type of gastric cancer. Conclusions: There is a trend in our country for a change in gastric tumour localization from distal to proximal, with clear significance for treatment choices.

• Archives of Reconstructive Microsurgery
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• v.14 no.1
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• pp.50-56
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• 2005

There are limited treatment options in the reconstruction of the very large defect in the metaphyseal portion of distal femur and proximal tibia. Fibula is one of the most popular donor of the long bone reconstruction in reconstructive microsurgical field. It has many advantages such as very strong strut tubular bone, very reliable vascular anatomy with large vascular diameter and long pedicle. There are limited donor site problems such as transient peroneal nerve dysfunction. In those situations with the huge long bone defects in distal femur or proximal tibia, the defective bony shape and strength of the transplanted fibular bone is not enough if only one strut of the fibula is transferred. We performed 7 cases of "doule barrel" fibular transplantation on the metaphyseal portion of distal femur and proximal tibial large defects in which it is very difficult to fill the bony gap with conventional bone graft or callotasis methods. It takes averaged 8.3 months since that procedure to obtain bony union. After solid union of the transferred double barrelled fibular graft. There were no stress fracture in our series. So we can propose double barrel fibular graft is useful method in those cases with very large bone defect on the metaphysis of large long bone.

• Imaging Science in Dentistry
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• v.33 no.2
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• pp.91-95
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• 2003

Purpose : To compare the diagnostic accuracy of proximal caries detection between Kodak Insight film and the Biomedisys CDX2000HQ digital (CCD) sensor. Materials and Methods: 156 proximal surfaces of extracted teeth, 78 of which had chemical artificial caries, were used in this study. Four observers interpreted the radiographs using a five-point confidence rating scale to record their diagnoses. The results were analyzed by receiver operating characteristic curves, ANOVA and Kappa values. Result: Analysis using receiver operating characteristic curves revealed the areas under each curve which indicated a diagnostic accuracy of 0.951 in Insight and 0.952 in CDX2000HQ digital sensor. ANOVA revealed no significant differences between the two images with respect to caries detection. Kappa values indicated that the mean intra-observer agreement was 0.85 and inter-observer agreement 0.71 in conventional radiography. In digital radiography, the mean intra-observer agreement was 0.84 and inter-observer agreement 0.72. Conclusion: The results suggest that no significant difference exists between the two modalities for artificial caries detection and that CDX2000HQ was as good as Insight film for this purpose.

• Structural Engineering and Mechanics
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• v.72 no.2
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• pp.191-201
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• 2019

Finite element analysis is one of the most used tools for studying femoral neck fracture. Nerveless, consensus concerning either the choice of material characteristics, damage law and /or geometric models (linear on nonlinear) remains unreached. In this work, we propose a numerical quasi-brittle damage model to describe the behavior of the proximal femur associated with two methods to evaluate the Young modulus. Eight proximal femur finite elements models were constructed from CT scan data (4 donors: 3 women; 1 man). The numerical computations showed a good agreement between the numerical curves (load - displacement) and the experimental ones. A very encouraging result is obtained when a comparison is made between the computed fracture loads and the experimental ones ($R^2=0.825$, Relative error =6.49%). All specific numerical computation provided very fair qualitative matches with the fracture patterns for the sideway fall simulation. Finally, the comparative study based on 32 simulations adopting linear and nonlinear meshing led to the conclusion that the quantitatively results are improved when a nonlinear mesh is used.

• PNF and Movement
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• v.9 no.3
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• pp.25-29
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• 2011

Purpose : We investigated the effect of anti-flexion taping at the proximal interphalangeal joints on the gait in stroke patients with clawing toe. Methods : Nineteen patients (mean age $63.26{\pm}9.16$ years) with clawing toe were studied. Gait performance was measured under two different conditions : (1) non-tape (2) application of tape. Gait velocity, step time and stride length were examined with the GAITRite system Results : Compared to the non-tape control condition, step time of the hemiparetic side increased significantly after the application of tape(p=0.03). There was no significant mean differences between the taped and control conditions for stride length of the hemiparetic side and velocity. Conclusion : Whilst the anti-flexion tape at the proximal interphalangeal joints changed the walking by providing significant step time effect, positive changes were noted in stride length of the hemiparetic side after tape application. These findings indicate that anti-flexion tape procedures do not significantly alter stride length of the hemiparetic side and velocity.

• Journal of Korean Neurosurgical Society
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• v.65 no.4
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• pp.514-522
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• 2022

Objective : A distal navigation of a large bore aspiration catheter during mechanical thrombectomy (MT) is important. However, delivering a large bore aspiration catheter is difficult to a tortuous or atherosclerotic artery. We report the experience of anchoring with balloon guide catheter (BGC) and stent retriever to facilitate the passage of an aspiration catheter in MT. Methods : When navigating an aspiration catheter failed with a conventional co-axial microcatheter delivery, an anchoring technique was used. Two types of anchoring technique were applied to facilitate distal navigation of a large bore aspiration catheter during MT. First, a passage of aspiration catheter was attempted with a proximal BGC anchoring technique. If this technique also failed, another anchoring technique with distal stent retriever was tried. Consecutive patients who underwent MT with an anchoring technique were identified. Details of procedure, radiologic outcomes, and safety variables were evaluated. Results : A total of 67 patients underwent MT with an anchoring technique. Initial trial of aspiration catheter passage with proximal BGC anchoring technique was successful for 35 patients (52.2%) and the second trial with distal stent retriever anchoring was successful for 32 patients (47.8%). Overall, navigation of a large bore aspiration catheter was successful for all patients (100%) without any procedure related complications. Conclusion : Our study showed the usefulness of anchoring technique with proximal BGC and distal stent retriever during MT, especially in those with an unfavorable anatomical structure. This technique could be an alternative option for delivering an of aspiration catheter to a distal location.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.135-146
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• 2005

In this paper, we suggest and analyze a class of iterative methods for solving hemiequilibrium problems using the auxiliary principle technique. We prove that the convergence of these new methods either requires partially relaxed strongly monotonicity or pseudomonotonicity, which is a weaker condition than monotonicity. Results obtained in this paper include several new and known results as special cases.

• Journal of dental hygiene science
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• v.16 no.5
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• pp.349-354
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• 2016

The purpose of this study was to evaluate the efficacy of the newly-developed $Qraypen^{TM}$ (All In One Bio, Korea) system for the diagnosis of early proximal caries by comparing it with the conventional methods of visual inspection and periapical radiography. This study was carried out from July 2015 to April 2016 targeting 32 children aged 7~12 years who visited Y-Dental Clinic for school oral health examinations. Two investigators selected and examined a total of 153 primary molars that had not undergone restorative treatment. Comparisons were carried out between visual inspections, readings of posterior periapical radiography images, and readings of $Qraypen^{TM}$ images. This study revealed that the percentage of interproximal surfaces of primary molar teeth without caries incidence was 83.7% using $Qraypen^{TM}$ imaging and 84.9% using visual inspection and periapical radiography. The differences between the two methods were not statistically significant. Thus, $Qraypen^{TM}$ is expected to be a useful and convenient auxiliary diagnostic device that can facilitate the detection of hidden proximal caries in primary molars.