• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.4_1
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• pp.299-309
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• 2014

This paper evaluated the possibility for 1/5,000 digital topographic mapping by using PLEIADES images of 0.5m GSD(Ground Sampling Distance) resolution that has recently launched. Those results of check points by applying the initial RPC(Rational Polynomial Coefficient) of PLEIADES images came out as; RMSE of those were $X={\pm}1.806m$, $Y={\pm}2.132m$, $Z={\pm}1.973m$. Also, if we corrected geometric correction using 16 GCP(Ground Control Point)s, the results of RMSE became $X={\pm}0.104m$, $Y={\pm}0.171m$, $Z={\pm}0.036m$, and t he RMSE of check points were $X={\pm}0.357m$, $Y={\pm}0.239m$, $Z={\pm}0.188m$; which of those results indicated the accuracy of standard adjustment complied in error tolerances of the 1/5,000 scale. Additionally, we converted coordinates of points, obtained by TerraSAR. for comparing with measurements from GPS(Global Positioning System) surveying. The RMSE of comparing converted and GPS points were $X={\pm}0.818m$, $Y={\pm}0.200m$, $Z={\pm}0.265m$, which confirmed the possibility for 1/5,000 digital topographic mapping with PLEIADES images and GCPs. As method of obtaining GCPs in unaccessible area, however, the outcome evaluation of GCPs extracted from TerraSAR images was not acceptable for 1/5,000 digital topographic mapping. Therefore, we considered that further researches are needed on applicability of GCPs extracted from TerraSAR images for future alternative method.

• Archives of Plastic Surgery
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• v.44 no.3
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• pp.210-216
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• 2017

Background In treating minor-form or microform cleft lip, obtaining an optimal result is a challenge because of the visible scarring caused by traditional surgery. We present a refined method using muscle overlapping with a minimal skin incision in patients younger than 3 years, a group characterized by thin muscle. Methods The surgical technique involves restoration of the notched vermillion using Z-plasty, formation of the philtral column using overlapping of an orbicularis oris muscle flap through an intraoral incision, and correction of the cleft lip nasal deformity using a reverse-U incision and V-Y plasty. A single radiologist evaluated ultrasonographic images of the upper lip. Results Sixty patients were treated between September 2008 and June 2014. The age at the time of operation ranged from 6 to 36 months (mean, 26 months). The follow-up period ranged from 8 to 38 months (mean, 20 months) in minor-form cases and from 14 to 64 months (mean, 37 months) in microform cases. A notched cupid's bow was corrected in 10 minor-form cases and 50 microform cases. Ultrasonographic images were obtained from 3 patients with minor-form cleft lip and 9 patients with microform cleft lip 12 months after surgery. The average muscle thickness was 4.5 mm on the affected side and 4.1 mm on the unaffected side. Conclusions The advantages of the proposed procedure include the creation of an anatomically natural philtrum with minimal scarring. This method also preserves the continuity and function of the muscle and provides sufficient augmentation of the philtral column and nostril sill.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.13.1-13.12
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• 2016

Background: Mandibular motion tracking system (ManMoS) has been developed for orthognathic surgery. This article aimed to introduce the ManMoS and to examine the accuracy of this system. Methods: Skeletal and dental models are reconstructed in a virtual space from the DICOM data of three-dimensional computed tomography (3D-CT) recording and the STL data of 3D scanning, respectively. The ManMoS uniquely integrates the virtual dento-skeletal model with the real motion of the dental cast mounted on the simulator, using the reference splint. Positional change of the dental cast is tracked by using the 3D motion tracking equipment and reflects on the jaw position of the virtual model in real time, generating the mixed-reality surgical simulation. ManMoS was applied for two clinical cases having a facial asymmetry. In order to assess the accuracy of the ManMoS, the positional change of the lower dental arch was compared between the virtual and real models. Results: With the measurement data of the real lower dental cast as a reference, measurement error for the whole simulation system was less than 0.32 mm. In ManMoS, the skeletal and dental asymmetries were adequately diagnosed in three dimensions. Jaw repositioning was simulated with priority given to the skeletal correction rather than the occlusal correction. In two cases, facial asymmetry was successfully improved while a normal occlusal relationship was reconstructed. Positional change measured in the virtual model did not differ significantly from that in the real model. Conclusions: It was suggested that the accuracy of the ManMoS was good enough for a clinical use. This surgical simulation system appears to meet clinical demands well and is an important facilitator of communication between orthodontists and surgeons.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.342-345
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• 2007

Purpose: A common side effect of the scalp reduction is a creation of a 'slot' with the hair growing in the opposite directions away from the scar. Overcoming the unnatural appearance of the slot has been a vexing problem in the scalp reduction surgery. None of the conventional corrective surgical techniques provides a complete and satisfactory aesthetic result. The Frechet flap is a triple transposition flap used for the correction of the slot defect secondary to scalp reduction surgery, seldom needing further scar revision. The Frechet technique provides a solution to the problem of the central slot concealment that is unattainable by other means, such as; Z-plasty and mini-graft. Methods: Authors applied the Frechet technique to Asian patients who had undergone scalp reduction and operated on 4 patients from March, 2000 to January, 2001. Average follow-up period was 13 months. Patients with long scars passing through the temporoparietoccipital zone were excluded. All the undermining was performed in the subgaleal plane, reaching the upper auricular sulcus and stopping just above the nuchal ridge. Results: None of the patients experienced infection, hematoma, nor any permanent hair loss. Transient telogen effluvium at the distal end of flap 2 and 3 was noticeable in one case. Conclusion: In conclusion, the results are aesthetically satisfactory without any significant complications.

• Journal of Radiation Industry
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• v.12 no.4
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• pp.267-276
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• 2018

A Hoffman 3D Brain Phantom was used to evaluate two PET/CT scanners, BIO_40 and D_690, according to the radiation dose of CT (low, medium and high) at a fixed kilo-voltage-peak (kVp) with the tube current(mA) varied in 17~20 stages(Bio_40 PET/CT scanner: the tube voltage was fixed to 120 kVp, the effective tube current(mAs) was increased from 33 mAs to 190 mAs in 10 mAs increments, D_690 PET/CT scanner: the tube voltage was fixed to 140 kVp, tube current(mA) was increased from 10 mAs to 200 mAs in 10 mAs increments). After obtaining the PET image, an attenuation correction was conducted based on the attenuation map, which led to an analysis of the difference in the image. First, the ratio of white to gray matter for each scanner was examined by comparing the coefficient of variation (CV) depending on the average ratio. In addition, a blind test was carried out to evaluate the image. According to the study results, the BIO_40 and D_690 scanners showed a <1% change in CV value due to the tube current conversion. The change in the coefficients of white and gray matter showed that the Z value was negative for both scanners, indicating that the coefficient of gray matter was higher than that of white matter. Moreover, no difference was observed when the images were compared in a blind test.

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.16-22
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• 2019

Background Various surgical techniques have been used to correct Tessier number 7 craniofacial cleft, which involves macrostomia, ear deformity, and hemifacial microsomia. To achieve symmetrical and satisfactory results in patients with macrostomia, the authors performed a 1-mm medial overcorrection on the cleft side and evaluated the results of this procedure. Methods A retrospective medical record review of patients diagnosed with Tessier number 7 craniofacial cleft from March 1999 to February 2017 was performed. Using clinical photographs, outpatient clinic records, and operative records, information was recorded regarding concurrent congenital anomalies, postoperative complications, and follow-up. Using Photoshop CS2, the length of both sides of the lip was compared. The ratio of these lengths was calculated to evaluate lip symmetry. Results Of the patients treated at the Department of Plastic and Reconstructive Surgery at Kyungpook National University Chilgok Hospital, 11 (male-to-female sex ratio, 7:4) were diagnosed with Tessier number 7 craniofacial cleft. Concurrent congenital anomalies included skin tag, hemifacial microsomia, and cleft palate. The mean duration of follow-up was $78.273{\pm}72.219$ months and the mean ratio of the lengths of both sides of the lip was $1.048{\pm}0.071$. Scar widening occurred as a postoperative complication in some patients. No cases of wound infection, bleeding, or wound dehiscence occurred. Conclusions For the successful correction of macrostomia, plastic surgeons should consider both functional and aesthetic problems of the lip. Adequate repair of the orbicularis oris muscle, skin closure with Z-plasty, and medial overcorrection of the neo-oral commissure led to good results in our patients.

• Journal of radiological science and technology
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• v.45 no.6
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• pp.553-560
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• 2022

The purpose of this study is to evaluate the clinical risk according to the applicator heterogeneity, mislocation, and tissue heterogeneity correction through a dose verification program during brachytherapy of cervical cancer. We performed image processing with MATLAB on images acquired with CT simulator. The source was modeled and stochiometric calibration and Monte-Carlo algorithm were applied based on dwell time and location to calculate the dose, and the secondary cancer risk was evaluated in the dose verification program. The result calculated by correcting for applicator and tissue heterogeneity showed a maximum dose of about 25% higher. In the bladder, the difference in excess absolute risk according to the heterogeneity correction was not significant. In the rectum, the difference in excess absolute risk was lower than that calculated by correcting applicator and tissue heterogeneity compared to the water-based calculation. In the femur, the water-based calculation result was the lowest, and the result calculated by correcting the applicator and tissue heterogeneity was 10% higher. A maximum of 14% dose difference occurred when the applicator mislocation was 20 mm in the Z-axis. In a future study, it is expected that a system that can independently verify the treatment plan can be developed by automating the interface between the treatment planning system and the dose verification program.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.41-44
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• 2010

Purpose: The epicanthus is a specific feature in Asian. Many techniques have been described to eliminate the epicanthal fold: resection of glabellar skin, resection of medial canthal skin, V-Y advancement, V-W technique, modified Z-plasty, multiple Z-plasties, and others. The authors observed postoperative epiphora after correction of epicanthal fold by periciliary skin flap without damaging lacrimal duct. Methods: A 19-year-old woman underwent non-incisional blepharoplasty, septorhinoplasty, and periciliary epicanthoplasty. On her history, she didn't have any symptom of epiphora preoperatively. And there was no specific complaint of epiphora during the postoperative two weeks. However epiphora got worse from one month after the surgery. She was out of this country, so the patient re-visited the clinic on the postoperative six months for this on-going symptom. On an ophthalmologic examination, patient's lacrimal duct and sac was intact but both lacrimal puncta of the patient were covered with a thin membrane. This membrane was punctuated by a 25 gauge needle and dilated with a standard dilator. Results: After ophthalmologic treatment, no recurrence was observed during five weeks of follow-up periods. Conclusion: Both lacrimal puncta of the patient were only covered with membranes. And we could not confirm the direct relationship between periciliary epicanthoplasty and postoperative epiphora. The probable factors will be a predisposing narrowed punctum, post operative peri-punctal edema and decrease in muscular function of orbicularis oculi.

• Investigative Magnetic Resonance Imaging
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• v.19 no.3
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• pp.168-177
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• 2015

Purpose: Brain surface intensity model (BSIM)-based cortical thickness analysis does not require complicated 3D segmentation of brain gray/white matters. Instead, this technique uses the local intensity profile to compute cortical thickness. The aim of the present study was to evaluate intra-rater and inter-rater reliability of BSIM-based cortical thickness analysis using images from elderly participants. Materials and Methods: Fifteen healthy elderly participants (ages, 55-84 years) were included in this study. High-resolution 3D T1-spoiled gradient recalled-echo (SPGR) images were obtained using 3T MRI. BSIM-based processing steps included an inhomogeneity correction, intensity normalization, skull stripping, atlas registration, extraction of intensity profiles, and calculation of cortical thickness. Processing steps were automatic, with the exception of semiautomatic skull stripping. Individual cortical thicknesses were compared to a database indicating mean cortical thickness of healthy adults, in order to produce Z-score thinning maps. Intra-class correlation coefficients (ICCs) were calculated in order to evaluate inter-rater and intra-rater reliabilities. Results: ICCs for intra-rater reliability were excellent, ranging from 0.751-0.940 in brain regions except the right occipital, left anterior cingulate, and left and right cerebellum (ICCs = 0.65-0.741). Although ICCs for inter-rater reliability were fair to excellent in most regions, poor inter-rater correlations were observed for the cingulate and occipital regions. Processing time, including manual skull stripping, was $17.07{\pm}3.43min$. Z-score maps for all participants indicated that cortical thicknesses were not significantly different from those in the comparison databases of healthy adults. Conclusion: BSIM-based cortical thickness measurements provide acceptable intra-rater and inter-rater reliability. We therefore suggest BSIM-based cortical thickness analysis as an adjunct clinical tool to detect cortical atrophy.

• Archives of Plastic Surgery
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• v.40 no.2
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• pp.97-103
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• 2013

Background Velopharyngeal insufficiency (VPI) may persist after primary repair of the cleft palate, and surgical correction is necessary in many cases. The purpose of this study is to evaluate the effect of double opposing Z-plasty (DOZ) in cleft palate patients suffering from VPI after primary two-flap palatoplasty. Methods Between March 1999 and August 2005, we identified 82 patients who underwent two-flap palatoplasty for cleft palate repair. After excluding the patients with congenital syndrome and mental retardation, 13 patients were included in the final study group. The average age of the patients who underwent DOZ at was 5 years and 1 month. Resonance, nasal emission, and articulation were evaluated by a speech pathologist. The velopharyngeal gaps were measured before and after surgery. Results Six patients attained normal speech capabilities after DOZ. The hypernasality grade was significantly improved after surgery in all of the patients (P=0.0015). Whereas nasal emission disappeared in 8 patients (61.5%), it was diminished but still persisted in the remaining 5 patients. Articulation was improved in all of the cases. In two cases, the velopharyngeal gap was measured using a ruler. The gap decreased from 11.5 to 7 mm in one case, and from 12.5 to 8 mm in the second case. Conclusions The use of DOZ as a surgical option to correct VPI has many advantages compared with other procedures. These include short surgery time, few troublesome complications, and no harmful effects on the dynamic physiological functioning of the pharynx. This study shows that DOZ can be another option for surgical treatment of patients with VPI after two-flap palatoplasty.