• Title/Summary/Keyword: contouring

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Hippocampal Sparing Whole Brain Radiotherapy and Integrated Simultaneous Boost vs Stereotactic Radiosurgery Boost: A Comparative Dosimetric Planning Study

  • Cheah, Soon Keat;Matthews, Thomas;Teh, Bin Sing
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.9
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    • pp.4233-4235
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    • 2016
  • Background: Whole brain radiotherapy (WBRT) and stereotactic radiosurgery were frequently used to palliate patients with brain metastases. It remains controversial which modality or combination of therapy is superior especially in the setting of limited number of brain metastases. The availability of newer medical therapy that improves survival highlighted the importance of reducing long term radiation toxicity associated with WBRT. In this study, we aim to demonstrate the hippocampal sparing technique with whole brain and integrated simultaneous boost Materials and Methods: Planning data from 10 patients with 1-5 brain metastases treated with SRS were identified. Based on the contouring guideline from RTOG atlas, we identified and contoured the hippocampus with 5mm isocentric expansion to form the hippocampal avoidance structure. The plan was to deliver hippocampal sparing whole brain radiotherapy (HSWBRT) of 30 Gy in 10 fractions and simultaneous boost to metastatic lesions of 30 Gy in 10 fractions each. Results: The PTV, hippocampus and hippocampal avoidance volumes ranges between 1.00 - 39.00 cc., 2.50 - 5.30 cc and 26.47 - 36.30 cc respectively. The mean hippocampus dose for the HSWBRT and HSWBRT and SIB plans was 8.06 Gy and 12.47 respectively. The max dose of optic nerve, optic chiasm and brainstem were kept below acceptable range of 37.5 Gy. Conclusions: The findings from this dosimetric study demonstrated the feasibility and safety of treating limited brain metastases with HSWBRT and SIB. It is possible to achieve the best of both worlds by combining HSWBRT and SIB to achieve maximal local intracranial control while maintaining as low a dose as possible to the hippocampus thereby preserving memory and quality of life.

Effective Reduction Malarplasty Considering Pivot Point (추축 (Pivot Point)를 고려한 효과적인 관골 축소성형술)

  • Ha, Ju-Ho;Kim, Yong-Ha;Kim, Tae-Gon;Lee, Jun-Ho
    • Archives of Plastic Surgery
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    • v.38 no.3
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    • pp.287-294
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    • 2011
  • Purpose: Reduction malarplasty is one of the common aesthetic procedures performed in the Orient. We have analyzed effective operative methods according to the pivot point for the osteotomy and reposition of the zygoma for reduction malarplasty after confirming the shapes of the individual zygomas. Methods: Thirty-six patients had been received malarplasty over the last 10 years. The average follow-up period was 16 months. We categorized the patients into three groups according to their prominent appearance features. Group I had a prominently protruded zygomatic body, group II had a prominently protruded zygomatic arch, and group III had a prominently protruded body and zygomatic arch. In the group I, two parallel oblique osteotomies on the body, the middle portion was removed, and with the zygomatic arch as the pivot point, the body was repositioned inwards. In the group II, the zygomatic body and arch osteotomy is performed, with the body as the pivot point, and the arch is depressed medially. In the group III, using the two aforementioned methods, the zygoma was repositioned medially. In each case, postoperative complications and patients satisfaction over the surgery were surveyed. Results: Each group had 25, 5 and 12 patients respectively. No significant complications were found except for one patient who experienced a non-union of zygomatic bone. In the case of group I, four patients underwent a secondary operation. Conclusion: Reduction malarplasty is popular as an effective facial contouring surgery. In order to obtain more effective results,however, the zygomatic shape should be identified, and appropriately repositioned by different operative technique according to pivot points.

Use of Cardiac Computed Tomography for Ventricular Volumetry in Late Postoperative Patients with Tetralogy of Fallot

  • Kim, Ho Jin;Mun, Da Na;Goo, Hyun Woo;Yun, Tae-Jin
    • Journal of Chest Surgery
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    • v.50 no.2
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    • pp.71-77
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    • 2017
  • Background: Cardiac computed tomography (CT) has emerged as an alternative to magnetic resonance imaging (MRI) for ventricular volumetry. However, the clinical use of cardiac CT requires external validation. Methods: Both cardiac CT and MRI were performed prior to pulmonary valve implantation (PVI) in 11 patients (median age, 19 years) who had undergone total correction of tetralogy of Fallot during infancy. The simplified contouring method (MRI) and semiautomatic 3-dimensional region-growing method (CT) were used to measure ventricular volumes. Results: All volumetric indices measured by CT and MRI generally correlated well with each other, except for the left ventricular end-systolic volume index (LV-ESVI), which showed the following correlations with the other indices: the right ventricular end-diastolic volume index (RV-EDVI) (r=0.88, p<0.001), the right ventricular end-systolic volume index (RV-ESVI) (r=0.84, p=0.001), the left ventricular end-diastolic volume index (LV-EDVI) (r=0.90, p=0.001), and the LV-ESVI (r=0.55, p=0.079). While the EDVIs measured by CT were significantly larger than those measured by MRI (median RV-EDVI: $197mL/m^2$ vs. $175mL/m^2$, p=0.008; median LV-EDVI: $94mL/m^2$ vs. $92mL/m^2$, p=0.026), no significant differences were found for the RV-ESVI or LV-ESVI. Conclusion: The EDVIs measured by cardiac CT were greater than those measured by MRI, whereas the ESVIs measured by CT and MRI were comparable. The volumetric characteristics of these 2 diagnostic modalities should be taken into account when indications for late PVI after tetralogy of Fallot repair are assessed.

Vaginal Dose, Toxicity and Sexual Outcomes in Patients of Cervical Cancer Undergoing Image Based Brachytherapy

  • Rai, Bhavana;Dhanireddy, Bhaswanth;Patel, Firuza Darius;Kumari, Reena;Oinam, Arun Singh;Simha, Vijai;Sharma, Suresh
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3619-3623
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    • 2014
  • Background: The aim of the study was to evaluate the vaginal dose and toxicity in patients of cervical cancer treated with image guided brachytherapy at our institute. Materials and Methods: Thirty-five patients treated with image based brachytherapy for cervical cancer were included. Vaginal contouring was done on MRI at brachytherapy and with CT scans of subsequent brachytherapy fractions. Dose volume parameters (DVH) were reported in accordance with the GEC-ESTRO guidelines. These were correlated with vaginal toxicity (assessed by CTCAE version 3) and quality of sexual life assessed at one year of completion of treatment. Results: Vaginal shortness was observed in 22 out of 30 (62.8%) patients, Nine (25.7%) had vaginal dryness and in 10 (28.5%) patients, there was contact bleeding. No association could be demonstrated between the dose volume parameters and vaginal toxicity in the present study. Conclusions: The lack of association between dose volume parameters of vagina with vaginal morbidity may be due to uncertainties involved in the delineation of vaginal wall and dosimetry. Future research is required to accurately define vaginal dose distribution to study its correlation with vaginal morbidity. Vaginal morbidity needs to be documented in order to improve the sexual outcome in these patients.

REDUCTION MALARPLASTY THROUGH INTRAORAL APPROACH (구개 접근법에 의한 협골 축소 성형술)

  • Woo, Soon-Seop;Kim, Myung-Jin;Min, Byong-Il
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.15 no.3
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    • pp.171-177
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    • 1993
  • The prominent malar region has been recognized a sign of youth and beauty in caucasian who generally have a dolichocephalic and long face. But in the orients, especially Koreans who generally have a mesocephalic or brachycephalic face, it is considered an agressive, unesthetic facial appearance. So many patients require the shaving of prominent malar eminence and arch, and many methods of its reduction have been devised. For the exposure of malar complex, infraorbital skin incision, intraoral approach, preauricular approach, supraauricular scalp incision, and coronal approach have been used. And for the reduction of bony structure, direct shaving, contouring and repositioning of the malar complex after extirpation, and medially fracture of zygomatic arch have been used with its own merits. We performed the reduction malarplasty through intraoral approach. After two parallel oeteotomy at medial part of the zygomatic bone, the midsegment is removed. The posterior arch of zygoma was bended or green stick fractured. When more correction was required, the posterior arch was fractured medially through the step incision at skin. This method has a some advantages. Compared with the method for extirpation of malar complex, the infection rate is diminished, the resorption is small because of no free bone graft. And cheek drooping is prevented. Compared with the method of coronal approach, the surgical trauma is minimal. Now we report some cases of reduction malarplasty performed through intraoral approach and disscus the surgical technique and results.

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GONIAL ANGLE REDUCTION DURING MANDIBULAR SAGITTAL SPLIT RAMUS OSTEOTOMY (하악지 시상 분할골절단술과 동시에 시행되는 우각부 절제술)

  • Kim, Jae-Seung;Chang, Hyun-Ho;Ryu, Sung-Ho;Kang, Jae-Hyun;Lee, Seung-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.3
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    • pp.258-265
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    • 2001
  • A prognathic mandible and prominent gonial angle are considered to be unattractive in the Orient because it gives the face a square and muscular appearance. Requests for contouring of the mandibular angle are rare in the other race but are much more common in Korea and, through out the Orient. So, we often encounter a patient with a prognathic mandible and squarish or broad face who wishes to have his or her facial size reduced minimally or to acquire a round or slender appearance. But, mandibular angle is located in the deepest part of the operative field and the strong tension of the lateral soft tissue makes retraction difficult. It is extremely difficult to reduce the gonial angle with sagittal split ramus osteotomy by intraoral approach at the same time. We apply the method of gonial angle reduction during SSRO and had satisfactory results. We will present our results and hope to give some useful information for management of mandibular deformity.

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Arthroscopic Subacromial Decompression for Chronic Impingement (견관절 만성 충돌 증후군의 관절경적 견봉하 감압술)

  • Lee Kwang-Won;Park Jong-Hyeun;Choy Won-Sik
    • Clinics in Shoulder and Elbow
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    • v.1 no.2
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    • pp.160-166
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    • 1998
  • The purpose of this study was to assess the results of arthroscopic subacromial decompression in patients with chronic impingement and to evaluate the results according to the rotator cuff pathology. We evaluated the clinical results of treatment for chronic impingement syndrome in 28 patients from Feb 1996 to Feb 1997. There were twenty men and eight women in age from 24 to 72 years (mean age 51) with dominant arm involvement in sixteen patients. Follow up evaluations averaged 15(range 12-24)months. The average duration of symptoms were 15(range 6­60)months. The final diagnoses which were based on the physical examination, plain radiographs and arthroscopic findings, were stage II impingement in 16 patients and stage ill impingement in 12 patients. We excluded the patients with acromioclavicular arthritis or glenohumeral instability in this study. All patients were managed non-operatively a minimum of six months. During the operation we performed contouring and smoothing the acromial undersurface and only resecting of the anterolateral band of the coracoacromial ligament. The clinical results were quantitated using UCLA shoulder rating score. Satisfactory results were obtained in 23(80%) patients. Unsatisfactory results were obtained in 5(18%) patients with posterior cuff tear. The average UCLA pain score showed significant improvement from 2.8(constant pain) to 7.2(present during heavy activities) at final follow up. The function and active forward flexion scores also increased from their preoperative value. There was no significant differences according to the surface and severity of tear and NeeI' stage (P>0.05). These results compared favorably with those reported following open acromioplasty. While arthroscopic subacromial decompression is a demanding technique with a learning curve, it is a reliable treatment for chronic impingement syndrome. A less aggressive approach to subacromial decompression and preserving the posteromedial band of the coracoacromialligament does not appear to compromise results.

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Effect of Rotating Speed and Air Flow Rate on Material Removal Characteristics in Abrasive Fluidized Bed Machining of Polyacetal (폴리아세탈의 입자유동베드 가공에서 회전속도와 공기 유량이 재료제거 특성에 미치는 영향)

  • Jang, Yangjae;Kim, Taekyoung;Hwang, Heondeok;Seo, Joonyoung;Lee, Dasol;Lee, Hyunseop
    • Tribology and Lubricants
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    • v.33 no.5
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    • pp.214-219
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    • 2017
  • Abrasive fluidized bed machining (AFBM) is similar to general abrasive fluidized machining (AFM) in that it can perform polishing of the outer and inner surfaces of a 3-dimensional shape by the flow of particles. However, in the case of AFM, the shear force generated by the flow of the particles causes material removal, while in AFBM, the abrasive particles are suspended in the chamber to form a bed. AFBM can be used for deburring, polishing, edge contouring, shot peening, and cleaning of mechanical parts. Most studies on AFBM are limited to metals, and research on application of AFBM to plastic materials has not been performed yet. Therefore, in this study, we investigate the effect of rotating speed of the specimen and the air flow rate on the material removal characteristics during AFBM of polyacetal with a horizontal AFBM machine. The material removal rate (MRR) increases linearly with increase of the rotating speed of the main shaft because of the shear force between the particles of the fluidized bed and the rotation of the workpiece. The reduction in surface roughness tends to increase as the rotating speed of the main shaft increases. As the air flow rate increases, the MRR tends to decrease. At a flow rate of 70 L/min or more, the MRR remains almost constant. The reduction of the surface roughness of the specimen is found to decrease with increasing air flow rate.

Prevention of Complication and Management of Unfavorable Results in Reduction Malarplasty (광대뼈 축소성형술 시 합병증의 예방과 불만족스러운 결과에 대한 해결방안)

  • Yang, Jung Hak;Lee, Ji Hyuck;Yang, Doo Byung;Chung, Jae Young
    • Archives of Plastic Surgery
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    • v.35 no.4
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    • pp.465-470
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    • 2008
  • Purpose: Reduction malarplasty is a popular aesthetic surgery for contouring wide and prominent zygoma. However a few patients complain postoperative results and want to revise the midfacial contour. We analyzed the etiology of unfavorable results and treated unsatisfied midfacial contours after reduction malarplasty. Methods: Total 53 patients were performed secondary operation for correction of unfavorable results after primary reduction malarplasty from elsewhere. Midfacial contour was evaluated with plain films and three-dimensional computed tomography. Unfavorable midfacial contours were corrected by secondary malarplasty. Flaring of zygomatic arch was reduced with infracturing technique and prominent zygomatic body was reduced with shaving. Drooped or displaced zygoma complex has been suspended to higher position and fixed with interosseous wiring. As adjuvant procedure, autologous fat injection has been performed in the region of depressed zygomatic body region. Results: The etiology of unfavorable midfacial contour after reduction malarplasty was classified into 7 categories: undercorrection of zygomatic arch(n=8), undercorrection of zygomatic arch and undercorrection of zygomatic body(n=6), undercorrection of zygomatic arch and overcorrection of zygomatic body(n=28), overcorrection of zygomatic body(n=3), simple asymmetry(n=4), malunion(n=2) or nonunion(n=2). Slim and balanced malar contour was achieved with treatment. And most of the patients were satisfied with the results of the surgery. Conclusion: To prevent the unfavorable results after reduction malarplasty, complete analysis of facial contour, choice of appropriate operation technique, precise osteotomy under direct vision, and security of zygoma position are important.

Otoplasty with High Density Polyethylene Implant(MEDPOR®) (잠복이에서 고밀도 폴리에틸렌 삽입물(MEDPOR®)을 이용한 귀성형술)

  • Lee, Keun-Cheol;Kwon, Yong-Seok;Heo, Jung;Moon, Ju-Bong;Kim, Seok-Kwun
    • Archives of Plastic Surgery
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    • v.36 no.2
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    • pp.167-173
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    • 2009
  • Purpose: The key points of treatment of cryptotia are the elevation of invaginated ear helix and the correction of deformed cartilage. Prevention of stabilized cartilage contouring from returning to the previous state is also important. The authors carried otoplasty by modified Onizuka's method or Ohmori's method that conchal cartilage graft or high density polyethylene implant(MEDPOR$^{(R)}$) graft served as fixation after spreading posterior aspect of adhered antihelix and a splint for prevention of recurrence of cartilage deformities. The aim of this study is to reveal the availability of the high density polyethylene implant(MEDPOR$^{(R)}$) graft for the correction of cryptotia. Methods: We have repaired 17 cryptotic deformities using cartilage graft from cavum of concha(12 cases) or high density polyethylene implant(5 cases) for correction of deformed cartilage. We investigate the operative time, complications, and satisfaction of postoperative ear shape on both autogenous cartilage graft group and high density polyethylene implant graft group. Results: There was 1 case of reinvagination on autogenous cartilage graft group. Implant exposure was occurred on high density polyethylene implant graft group, as 1 case. These were statistically no differences between autogenous cartilage graft group and high density polyethylene implant graft group to the satisfaction of ear shape. Conclusion: High density polyethylene implant(MEDPOR$^{(R)}$) present an alternative to autogenous material as they allow of fibrovascular ingrowth, leading to stability of the implant and decreased infection rates. The correction of deformed cartilage by using the high density polyethylene implant(MEDPOR$^{(R)}$) is a good option for the treatment of cryptotia.