• Title/Summary/Keyword: Mean-Shift

Search Result 643, Processing Time 0.03 seconds

Daily Setup Uncertainties and Organ Motion Based on the Tomoimages in Prostatic Radiotherapy (전립선암 치료 시 Tomoimage에 기초한 Setup 오차에 관한 고찰)

  • Cho, Jeong-Hee;Lee, Sang-Kyu;Kim, Sei-Joon;Na, Soo-Kyung
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.19 no.2
    • /
    • pp.99-106
    • /
    • 2007
  • Purpose: The patient's position and anatomy during the treatment course little bit varies to some extend due to setup uncertainties and organ motions. These factors could affected to not only the dose coverage of the gross tumor but over dosage of normal tissue. Setup uncertainties and organ motions can be minimized by precise patient positioning and rigid immobilization device but some anatomical site such as prostate, the internal organ motion due to physiological processes are challenge. In planning procedure, the clinical target volume is a little bit enlarged to create a planning target volume that accounts for setup uncertainties and organ motion as well. These uncertainties lead to differences between the calculated dose by treatment planning system and the actually delivered dose. The purpose of this study was to evaluate the differences of interfractional displacement of organ and GTV based on the tomoimages. Materials and Methods: Over the course of 3 months, 3 patients, those who has applied rectal balloon, treated for prostatic cancer patient's tomoimage were studied. During the treatment sessions 26 tomoimages per patient, Total 76 tomoimages were collected. Tomoimage had been taken everyday after initial setup with lead marker attached on the patient's skin center to comparing with C-T simulation images. Tomoimage was taken after rectal balloon inflated with 60 cc of air for prostate gland immobilization for daily treatment just before treatment and it was used routinely in each case. The intrarectal balloon was inserted to a depth of 6 cm from the anal verge. MVCT image was taken with 5 mm slice thickness after the intrarectal balloon in place and inflated. For this study, lead balls are used to guide the registration between the MVCT and CT simulation images. There are three image fusion methods in the tomotherapy, bone technique, bone/tissue technique, and full image technique. We used all this 3 methods to analysis the setup errors. Initially, image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours and then the radiation therapist registered the MVCT images with the CT simulation images based on the bone based, rectal balloon based and GTV based respectively and registered image was compared with each others. The average and standard deviation of each X, Y, Z and rotation from the initial planning center was calculated for each patient. The image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours. Results: There was a significant difference in the mean variations of the rectal balloon among the methods. Statistical results based on the bone fusion shows that maximum x-direction shift was 8 mm and 4.2 mm to the y-direction. It was statistically significant (P=<0.0001) in balloon based fusion, maximum X and Y shift was 6 mm, 16mm respectively. One patient's result was more than 16 mm shift and that was derived from the rectal expansions due to the bowl gas and stool. GTV based fusion results ranging from 2.7 to 6.6 mm to the x-direction and 4.3$\sim$7.8 mm to the y-direction respectively. We have checked rotational error in this study but there are no significant differences among fusion methods and the result was 0.37$\pm$0.36 in bone based fusion and 0.34$\pm$0.38 in GTV based fusion.

  • PDF

Evaluating the usefulness of BinkieRTTM (oral positioning stent) for Head and Neck Radiotherapy (두경부암 환자 방사선 치료 시 BinkieRTTM(구강용 고정장치)에 대한 유용성 평가)

  • GyeongJin Lee;SangJun Son;GyeongDal Lim;ChanYong Kim;JeHee Lee
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.34
    • /
    • pp.21-30
    • /
    • 2022
  • Purpose: The purpose of this study is to evaluate the effectiveness of oral positioning stent, the BinkieRTTM in radiation treatment for head and neck cancer patients in terms of tongue positions reproducibility, tongue doses and material properties. Materials and Methods: 24 cases using BinkieRTTM during radiation treatments were enrolled. The tongue was contoured on planning CT and CBCT images taken every 3 days during treatment, and then the DSC and center of tongue shift values were analyzed to evaluate the reproducibility of the tongue. The tongue dose was compared in terms of dose distribution when using BinkieRTTM and different type of oral stents (mouthpiece, paraffin wax). Randomly selected respective 10 patients were measured tongue doses of initial treatment plan for nasal cavity and unilateral parotid cancer. Finally, In terms of material evaluation, HU and relative electron density were identified in RTPS. Results: As a result of DSC analysis, it was 0.8 ± 0.07, skewness -0.8, kurtosis 0.61, and 95% CI was 0.79~0.82. To analyze the deviation of the central tongue shift during the treatment period, a 95% confidence interval for shift in the LR, SI, and AP directions were indicated, and a one-sample t-test for 0, which is an ideal value in the deviation(n=144). As a result of the t-test, the mean and SD in the LR and SI directions were 0.01 ± 0.14 cm (p→.05), 0.03 ± 0.25 cm (p→.05), and -0.08 ± 0.25 cm (p ←.05) in the AP direction. In the case of unilateral parotid cancer patients, the Dmean to the tongue of patients using BinkieRTTM was 16.92% ± 3.58% compared to the prescribed dose, and 23.99% ± 10.86% of patients with Paraffin Wax, indicating that the tongue dose was relatively lower when using BinkieRTTM (p←.05). On the other hand, among nasal cavity cancer patients, the Dmean of tongue dose for patients who used BinkieRTTM was 4.4% ± 5.6%, and for those who used mouthpiece, 5.9% ± 6.8%, but it was not statistically significant (p→.05). The relative electron density of Paraffin Wax, BinkieRTTM and Putty is 0.94, 0.99, 1.26 and the mass density is 0.95, 0.99 and 1.32 (g/cc), Transmission Factor is 0.99, 0.98, 0.96 respectively. Conclusion: The result of the tongue DSC analysis over the treatment period was about 0.8 and Deviation of the center of tongue shifts were within 0.2 cm, the reproducibility was more likely excellent. In the case of unilateral head and neck cancer patients, it was found that the use of BinkieRTTM rather than Paraffin Wax or Putty can reduce the unnecessary dose irradiated to the tongue. This study might be useful to understand of BinkieRTTM's properties and advantages. And also it could be another considered option as oral stent to keep the reproducibility of tongue and reducing dose during head and neck radiation treatments.

Comparison of the Results between Anterior Cruciate Ligament Reconstruction alone and Combined with High Tibial Osteotomy for anterior Cruciate Ligament Ruptured Knees with Varus Alignment (전방 십자 인대 파열과 슬관절 내반 변형 동반시 근위 경골 절골술과 전방 십자 인대 재건술의 동반 치료와 전방 십자 인대 재건술의 단독 치료의 비교)

  • Kwak, Ji Hoon;Sim, Jae Ang;Lee, Yong Seuk;Hwang, Chul Ho;Lee, Beom Koo
    • Journal of the Korean Arthroscopy Society
    • /
    • v.17 no.1
    • /
    • pp.44-49
    • /
    • 2013
  • Purpose: To compare of the results between anterior cruciate ligament (ACL) reconstruction alone and combined with high tibial osteotomy for ACL ruptured knees with varus alignment. Materials and Methods: We retrospectively reviewed 8 cases of ACL reconstruction combined with high tibial osteotomy (Group I) and 13 cases of ACL reconstruction alone (Group II) for varus angulated ACL ruptured knees (from March 2005 to February 2007). Mean age were 34.1 years (range: 20-53) in Group I, 34.9 years (range: 21-50) in Group II. Average follow up period were 22.6 months (range: 12-35) in Group I, 20 months (range: 13-33) in Group II. We analyzed clinical and radiological results. Results: There were no significant differences in clinical and radiologic results between two groups for IKDC scores, Lysholm knee scores, Lachman test, pivot shift test, KT-2000 arthrometer, $30^{\circ}$ and $90^{\circ}$ anterior drawer stress radiographs. Tegner activity scales and Cincinnati knee ligament rating scales were 4.9, 57.9 in Group I, and 5.6, 72.9 in Group II. Group I was statistically lower than Group II for Tegner activity scales and Cincinnati knee ligament rating scales (p<0.05). Conclusion: There were no significant differences in daily living between ACL reconstruction alone and combined with high tibial ostetomy for varus angulated ACL ruptured knees. However, ACL reconstruction combined with high tibial osteotomy could limit sport activity ability.

  • PDF

MRI Findings of the Repaired Anterior Cruciate Ligament (전방 십자 인대의 일차 봉합술 후 MRI 소견)

  • Kim, Jung-Man;Koh, In-Jun;Lee, Dong-Yeob;Lee, Yoon-Min
    • Journal of the Korean Arthroscopy Society
    • /
    • v.13 no.1
    • /
    • pp.14-21
    • /
    • 2009
  • Purpose: To investigate MRI findings of the repaired anterior cruciate ligament (ACL). Materials and Methods: Seventeen of arthroscopic ACL primary repair with sutures pull-out technique were followed for 21.4 months (range: 12 to 60 months). Stability was assessed with physical examination and KT-1000 arthrometer (MED metric, San Diego, CA) and postoperative MRI checked with time. The patients were divided into 2 groups according to the location of tear which was defined with the location of remained synovial sleeve. Group I (11 patients) comprised that the tear was located within proximal 1/3 of ACL substance and group II (6 patients) comprised below proximal 1/3. MRI findings of the repaired ACL were evaluated by its course, sharpness, thickness and signal intensity using 3 grade system and correlated with its location of tear. Results: In all cases, Lachman test and flexion-rotation drawer test were negative, pivot-shift test was less than grade 1 and the mean side-to-side difference by use of KT-1000 arthrometer was 1.4 mm (range: -1.0 to 2.5 mm). The overall continuity of the repaired ACL was well maintained in all cases. However, mild sagging was observed in 10 cases(58.8%), mild obscure contour in 6 cases (35.3%), increased thickness in 8 cases (47.1%) and slight increased signal intensity in 5 cases (29.5%). There was no statistical significance in all parameters between 2 groups. And a focal defect at the femoral attachment site in sagittal image was observed in 7 cases (41.2%) of all patients which comprised 2 cases (18.2%) of group I and 5 cases (83.3%) of group II. It was observed more frequently in group II with statistical significance (p=0.035). Conclusion: Some abnormal MRI findings such as mild sagged course, obscure contour, increased thickness and signal intensity, the focal defect at femoral attachment site could be observed even though the stability was well maintained clinically. We thought that the focal defect was affected by the location of tear of ACL.

  • PDF

Mapping Man-Made Levee Line Using LiDAR Data and Aerial Orthoimage (라이다 데이터와 항공 정사영상을 활용한 인공 제방선 지도화)

  • Choung, Yun-Jae;Park, Hyen-Cheol;Chung, Youn-In;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.14 no.1
    • /
    • pp.84-93
    • /
    • 2011
  • Levee line mapping is critical to the protection of environments in river zones, the prevention of river flood and the development of river zones. Use of the remote sensing data such as LiDAR and aerial orthoimage is efficient for river mapping due to their accessibility and higher accuracy in horizontal and vertical direction. Airborne laser scanning (LiDAR) has been used for river zone mapping due to its ability to penetrate shallow water and its high vertical accuracy. Use of image source is also efficient for extraction of features by analysis of its image source. Therefore, aerial orthoimage also have been used for river zone mapping tasks due to its image source and its higher accuracy in horizontal direction. Due to these advantages, in this paper, research on three dimensional levee line mapping is implemented using LiDAR and aerial orthoimage separately. Accuracy measurement is implemented for both extracted lines generated by each data using the ground truths and statistical comparison is implemented between two measurement results. Statistical results show that the generated 3D levee line using LiDAR data has higher accuracy than the generated 3D levee line using aerial orthoimage in horizontal direction and vertical direction.

Evaluation of Corrosion Characteristics of Underwater Hardening Paint (수중 경화형도료의 부식특성에 관한 전기화학적 고찰)

  • Moon, Kyung-Man;Oh, Min-Seok;Lee, Myung-Hoon;Lee, Syung-Yul;Kim, Yun-Hae
    • Journal of Ocean Engineering and Technology
    • /
    • v.25 no.2
    • /
    • pp.85-91
    • /
    • 2011
  • Many protection methods such as surface coating, electric protection, or other methods have been applied to the numerous steel structures widely used in continental and marine areas to control their corrosion, which is done from an economic point of view. Most of these steel structures are primarily protected by coating methods. However, some steel piles under seawater are protected by the electric protection method, that is, either using an impressed current or a sacrificial anode method. Furthermore, environmental contamination may cause a severely corrosive environment, which, in turn, causes the accelerated corrosion of steel structures. Subsequently, coated steel structures could deteriorate more rapidly than the designed lifetime because of the acid rain caused by air pollution, etc. Therefore, a coating of marine paint exposed to seawater, that is, underwater hardening painting, is increasingly required to be fast drying as well as highly corrosion resistant. In this study, five types of underwater hardening paints were prepared with different resin series and additives. Their corrosion and water resistances were investigated using electrochemical methods such as corrosion potential, polarization curves, impedance and cyclic voltammogram measurements, etc. Even though it is generally accepted that the corrosion resistance of bare steel tends to increase with a shift of the corrosion potential in the noble direction, the corrosion resistance of a sample with a coating exhibited a relatively better tendency when it had a lower corrosion potential in this study. The corrosion current density was also decreased with a decrease in the diffusion limiting current density, which may mean that there is some relationship between corrosion and water resistance. The S sample of the ceramic resin series showed the relatively best corrosion and water resistance among those of samples, while the worst corrosion and water resistance were observed for the R sample of the epoxy resin series. The corrosion and water resistance of those samples tended to deteriorate with an increase in the immersion days, and their corrosion and water resistances were considered to be apparently improved by the types of resin and additives.

The Evaluation of Teicoplanin Usage in a University Hospital (대학병원에서의 Teicoplanin의 사용 현황 조사 및 실태 평가)

  • Kim, Eun A;Oh, Jung Mi
    • Korean Journal of Clinical Pharmacy
    • /
    • v.11 no.1
    • /
    • pp.19-29
    • /
    • 2001
  • Teicoplanin, a glycopeptide antibiotic, has potential for use as an alternative to vancomycin in the treatment of gram-positive bacterial infections. However, unlike vancomycin, there is a lack of study on teicoplanin's efficacy and safety and the guideline for its use is not available, yet. The objective of this study was to investigate and evaluate the pattern of teicoplanin usage in a university hospital. A retrospective study was performed on 72 adult patients, who took teicoplanin for 3 continuous days at D. University hospital from 1 January 1999 to 30 June 2000. The microorganisms treated with teicoplanin were methicillin-resistant Staphylocorcus aureus $(69\%)$, coagulase-negative Staphylococci $(12\%)$, Enterococcus $(4\%)$, vancomycin-resistant Enterococci $(2\%)$, Streptococci $(2\%)$, and Bacillus $(1\%)$. The types of infection treated with teicoplanin were surgical wound infection $(58\%)$, lower respiratory infection $(11\%)$, bactremia $(7\%)$, urinary tract infection $(5\%)$, pleural fluid infection $(4\%)$, and peritoneal fluid infection $(2\%)$. The mean duration of teicoplanin usage was 16.5 days and teicoplanin was used with 1.4 other antibiotics, which were aminoglycosides (isepamicin, amikacin, netilmicin, astromicin) or quinolones (ciprofloxacin, tosufloxacin) or the third generation cephalosporin (ceftazidime). Only 24 cases $(28.6\%)$ met with the criteria for the justification of use, and the rest of 60 cases $(71.4\%)$ did not meet the criteria. In 84 cases $(100\%)$, blood culture tests were performed prior to the initial dose of teicoplanin. In 83 cases $(99\%)$, serum creatinine were conducted before the initial doses. In 45 cases $(53.6\%)$, serum creatinine was monitored at least twice weekly. In 55 cases $(65.5\%)$, WBC was tested at least twice weekly. In 84 cases $(100\%)$, body temperature was monitored at least once per nursing shift. In 15 cases out of 56 cases, maximum temperature decreased at least 1 degree within 3 days of teicoplanin use. In 15 case out of 35 cases, WBC values were within the normal range after treatment. In 23 cases $(27.4\%)$, dosage regimen was appropriate. Drug-related adverse effects were reported in 13 cases. Nephrotoxicity (progressively increasing SCr. or sustained SCr increase of $\geq$0.5 mg/dl from baseline) was noted in five cases. Neutropenia (absolute neutrophil count <1,500 $cells/mm^3$) was noted in one case and eosinophilia (total eosinophil count >350 $cells/mm^3$) was noted in seven cases. A more strict control on use of teicoplanin is required, considering that teicoplanin is categorized as one of restricted antibiotics.

  • PDF

Evaluation of Setup Usefulness of CBCT using Rando Phantom (인체 팬텀(Rando Phantom)을 이용한 CBCT의 Setup 유용성 평가)

  • Jang, Eun-Sung
    • The Journal of the Korea Contents Association
    • /
    • v.11 no.7
    • /
    • pp.234-238
    • /
    • 2011
  • This paper will evaluate the usefulness of 3D target of CBCT by comparing human body's posture and position when simulated treatment is being carried out as well as human phantom posture and position using CBCT which is applying OBI. From the Rando Phantom which is located in the datum point moved in parallel and rotationary direction using CBCT. Then the mean and standard deviation difference on images location difference that are acquired were compared with real the Rando Phantom' moved distance. To make a plan of simulated treatment with the same procedure of real radiation therapy, we are going to setup the Rando Phantom. With an assumption that the position is set in accurate place, we measured the setup errors accroding to the change of the translation and rotation. Tests are repeated 10 times to get the standard deviation of the error values. The variability in couch shift after positioning equivalent to average residual error showed lateral $0.2{\pm}0.2$mm, longitudinal $0.4{\pm}0.3$mm, vertical $-0.4{\pm}0.1$mm. The average rotation erroes target localization after simulated $0.4{\pm}0.2$ mm, $0.3{\pm}0.3$ mm, and $0.3{\pm}0.4$ mm. The detection error by rotation is $0{\sim}0.6^{\circ}$ CBCT 3D/3D matching using the Rando Phantom minimized the errors by realizing accurate matching during simulated treatment and patient caring.

Risk Factors Associated with Subdural Hygroma after Decompressive Craniectomy in Patients with Traumatic Brain Injury : A Comparative Study

  • Jeon, Sei-Woong;Choi, Jong-Hun;Jang, Tae-Won;Moon, Seung-Myung;Hwang, Hyung-Sik;Jeong, Je-Hoon
    • Journal of Korean Neurosurgical Society
    • /
    • v.49 no.6
    • /
    • pp.355-358
    • /
    • 2011
  • Objective : Subdural hygroma (SDG) is a complication occurring after head trauma that may occur secondary to decompressive craniectomy (DC). However, the mechanism underlying SDG formation is not fully understood. Also, the relationship between the operative technique of DC or the decompressive effect and the occurrence and pathophysiology of SDG has not been clarified. Purpose of this study was to investigate the risk factors of SDG after DC in our series. Methods : From January 2004 to December 2008, DC was performed in 85 patients who suffered from traumatic brain injury. We retrospectively reviewed the clinical and radiological features. For comparative analysis, we divided the patients into 2 groups : one group with SDG after craniectomy (19 patients; 28.4% of the total sample), the other group without SDG (48 patients; 71.6%). The risk factors for developing SDG were then analyzed. Results : The mean Glasgow Outcome Scale (GOS) scores at discharge of the groups with and without SDG were 2.8 and 3.1, respectively (p<0.0001). Analysis of radiological factors showed that a midline shift in excess of 5 mm on CT scans was present in 19 patients (100%) in the group with SDG and in 32 patients (66.7%) in the group without SDG (p<0.05). An accompanying subarachnoid hemorrhage (SAH) was seen in 17 patients (89.5%) in the group with SDG and in 29 patients (60.4%) in the group without SDG (p<0.05). Delayed hydrocephalus accompanied these findings in 10 patients (52.6%) in the group with SDG, versus 5 patients (10.4%) in the group without SDG (p<0.05). On CT, compression of basal cisterns was observed in 14 members (73.7%) in the group with SDG and in 18 members of the group without SDG (37.5%) (p<0.007). Furthermore, tearing of the arachnoid membrane, as observed on CT, was more common in all patients in the group with SDG (100%) than in the group without SDG (31 patients; 64.6%) (p<0.05). Conclusion : GOS showed statistically significant difference in the clinical risk factors for SDG between the group with SDG and the group without SDG. Analysis of radiological factors indicated that a midline shifting exceeding 5 mm, SAH, delayed hydrocephalus, compression of basal cisterns, and tearing of the arachnoid membrane were significantly more common in patients with SDG.

Compare the Intracranial Pressure Trend after the Decompressive Craniectomy between Massive Intracerebral Hemorrhagic and Major Ischemic Stroke Patients

  • Huh, Joon;Yang, Seo-Yeon;Huh, Han-Yong;Ahn, Jae-Kun;Cho, Kwang-Wook;Kim, Young-Woo;Kim, Sung-Lim;Kim, Jong-Tae;Yoo, Do-Sung;Park, Hae-Kwan;Ji, Cheol
    • Journal of Korean Neurosurgical Society
    • /
    • v.61 no.1
    • /
    • pp.42-50
    • /
    • 2018
  • Objective : Massive intracerebral hemorrhage (ICH) and major infarction (MI) are devastating cerebral vascular diseases. Decompression craniectomy (DC) is a common treatment approach for these diseases and acceptable clinical results have been reported. Author experienced the postoperative intracranaial pressure (ICP) trend is somewhat different between the ICH and MI patients. In this study, we compare the ICP trend following DC and evaluate the clinical significance. Methods : One hundred forty-three patients who underwent DC following massive ICH (81 cases) or MI (62 cases) were analyzed retrospectively. The mean age was $56.3{\pm}14.3$ (median=57, male : female=89 : 54). DC was applied using consistent criteria in both diseases patients; Glasgow coma scale (GCS) score less than 8 and a midline shift more than 6 mm on brain computed tomography. In all patients, ventricular puncture was done before the DC and ICP trends were monitored during and after the surgery. Outcome comparisons included the ictus to operation time (OP-time), postoperative ICP trend, favorable outcomes and mortality. Results : Initial GCS (p=0.364) and initial ventricular ICP (p=0.783) were similar among the ICH and MI patients. The postoperative ICP of ICH patients were drop rapidly and maintained within physiological range if greater than 80% of the hematoma was removed. While in MI patients, the postoperative ICP were not drop rapidly and maintained above the physiologic range (MI=18.8 vs. ICH=13.6 mmHg, p=0.000). The OP-times were faster in ICH patients (ICH=7.3 vs. MI=40.9 hours, p=0.000) and the mortality rate was higher in MI patients (MI=37.1% vs. ICH=17.3%, p=0.007). Conclusion : The results of this study suggest that if greater than 80% of the hematoma was removed in ICH patients, the postoperative ICP rarely over the physiologic range. But in MI patients, the postoperative ICP was above the physiologic range for several days after the DC. Authors propose that DC is no need for the massive ICH patient if a significant portion of their hematoma is removed. But DC might be essential to improve the MI patients' outcome and timely treatment decision.