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31.
Neil A. Segal Michael C. Nevitt John A. Lynch Jingbo Niu James C. Torner Ali Guermazi 《The Physician and sportsmedicine》2013,41(3):213-220
Objective. To determine the diagnostic performance of standing computerized tomography (SCT) of the knee for osteophytes and subchondral cysts compared with fixed-flexion radiography, using MRI as the reference standard. Methods. Twenty participants were recruited from the Multicenter Osteoarthritis Study. Participants’ knees were imaged with SCT while standing in a knee-positioning frame, and with postero-anterior fixed-flexion radiography and 1T MRI. Medial and lateral marginal osteophytes and subchondral cysts were scored on bilateral radiographs and coronal SCT images using the OARSI grading system and on coronal MRI using Whole Organ MRI Scoring. Imaging modalities were read separately with images in random order. Sensitivity, specificity and accuracy for the detection of lesions were calculated and differences between modalities were tested using McNemar’s test. Results.Participants’ mean age was 66.8 years, body mass index was 29.6 kg/m2 and 50% were women. Of the 160 surfaces (medial and lateral femur and tibia for 40 knees), MRI revealed 84 osteophytes and 10 subchondral cysts. In comparison with osteophytes and subchondral cysts detected by MRI, SCT was significantly more sensitive (93 and 100%; p < 0.004) and accurate (95 and 99%; p < 0.001 for osteophytes) than plain radiographs (sensitivity 60 and 10% and accuracy 79 and 94%, respectively). For osteophytes, differences in sensitivity and accuracy were greatest at the medial femur (p = 0.002). Conclusions. In comparison with MRI, SCT imaging was more sensitive and accurate for detection of osteophytes and subchondral cysts than conventional fixed-flexion radiography. Additional study is warranted to assess diagnostic performance of SCT measures of joint space width, progression of OA features and the patellofemoral joint. 相似文献
32.
Liqiu Ma Yusuke Kazama Tomonari Hirano Ryouhei Morita Shuuitsu Tanaka Tomoko Abe 《International journal of radiation biology》2013,89(12):1125-1133
Purpose: To assess the unique biological effects of different forms of ionizing radiation causing DNA double-strand breaks (DSBs), we compared the killing effect, mutagenesis frequency, and mutation type spectrum using the model filamentous fungus Neurospora.Materials and methods: Asexual spores of wild-type Neurospora and two DSB repair-deficient strains [one homologous recombination- and the other non-homologous end-joining (NHEJ) pathway-deficient] were irradiated with argon (Ar)-ion beams, ferrous (Fe)-ion beams, or X-rays. Relative biological effectiveness (RBE), forward mutation frequencies at the ad-3 loci, and mutation spectra at the ad-3B gene were determined.Results: The canonical NHEJ (cNHEJ)-deficient strain showed resistance to higher X-ray doses, while other strains showed dose-dependent sensitivity. In contrast, the killing effects of Ar-ion and Fe-ion beam irradiation were dose-dependent in all strains tested. The rank order of RBE was Ar-ion?>?Fe-ion?>?C-ion. Deletion mutations were the most common, but deletion size incremented with the increasing value of linear energy transfer (LET).Conclusions: We found marked differences in killing effect of a cNHEJ-deficient mutant between X-ray and high-LET ion beam irradiations (Ar and Fe). The mutation spectra also differed between irradiation types. These differences may be due to the physical properties of each radiation and the repair mechanism of induced damage in Neurospora crassa. These results may guide the choice of irradiation beam to kill or mutagenize fungi for agricultural applications or further research. 相似文献
33.
目的 探索建立创伤后颅骨缺损数据库,为颅骨缺损的三维测量及个性化设计提供研究的平台。方法 对电子束CT扫描颅骨缺损的患者,应用自主开发的骨组织表面绘制软件3DMSR对CT原始数据进行分析处理和三维测量,并转换成适用于快速成型、个性化修复和数据库建立的通用格式。结果 1995年至2004年,对84例创伤后颅骨缺损的患者,应用电子束CT和计算机辅助设计技术进行三维测量和个性化手术模拟,根据不同病例的具体情况分别采用自体颅骨外板、自体下颌骨外板、MEDPOR、钛网及钛合金个性化修复体等方法完成治疗,并将相关信息建成颅骨缺损数据库。结论 颅骨缺损数据库的建立,对于个性化治疗方案及相关研究,具有积极的意义。 相似文献
34.
Electron beam sterilization does not have a detrimental effect on the ability of extracellular matrix scaffolds to support in vivo ligament healing 下载免费PDF全文
Benedikt L. Proffen Gabriel S. Perrone Braden C. Fleming Jakob T. Sieker Joshua Kramer Michael L. Hawes Gary J. Badger Martha M. Murray 《Journal of orthopaedic research》2015,33(7):1015-1023
Extracellular matrix (ECM) scaffolds have been used to enhance anterior cruciate ligament (ACL) repair in large animal models. To translate this technology to clinical care, identifying a method which effectively sterilizes the material without significantly impairing in vivo function is desirable. Sixteen Yorkshire pigs underwent ACL transection and were randomly assigned to bridge‐enhanced ACL repair—primary suture repair of the ACL with addition of autologous blood soaked ECM scaffold—with either (i) an aseptically processed ECM scaffold, or (ii) an electron beam irradiated ECM scaffold. Primary outcome measures included sterility of the scaffold and biomechanical properties of the scaffold itself and the repaired ligament at 8 weeks after surgery. Scaffolds treated with 15 kGy electron beam irradiation had no bacterial or fungal growth noted, while aseptically processed scaffolds had bacterial growth in all tested samples. The mean biomechanical properties of the scaffold and healing ligament were lower in the electron beam group; however, differences were not statistically significant. Electron beam irradiation was able to effectively sterilize the scaffolds. In addition, this technique had only a minimal impact on the in vivo function of the scaffolds when used for ligament healing in the porcine model. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1015–1023, 2015. 相似文献
35.
《Urologic oncology》2015,33(2):71.e11-71.e19
PurposeHistologic grade analyses for prostate cancer (PCa) have traditionally included Gleason scores (GS) of ≤6, 7, and 8-10. Stratified biochemical progression-free survival has increasingly been reported within these groups on analyses of primary-secondary patterns (PSPs) (e.g., 3+4 vs. 4+3) and overall GS (e.g., 8 vs. 9 vs. 10) but with limited data regarding stratified survival outcomes. In this analysis, outcomes for biopsy-assigned GS 6 to 10 were comprehensively evaluated to identify stratifications prognostic for survival in patients undergoing external beam radiation therapy (EBRT).MethodsThe Surveillance, Epidemiology, and End Results database was examined for T1–4 N0 M0, GS 6 to 10 PCa managed with EBRT alone from 2004 to 2006. GS and PSP variations were analyzed for PCa-specific survival (PCSS) and overall survival (OS).ResultsOverall, 26,885 patients were evaluated. Preliminary PSP analyses identified stratifications for 3+4 vs. 4+3 = 7 and 4+4 = 8 vs. GS 8 with pattern 5 (P5) (i.e., 3+5 and 5+3) as significant; however, no differences were observed for 4+5 vs. 5+4 = 9. The primary analysis included stratifications for GS 6, 3+4, 4+3, 4+4, 8 w/P5, 9, and 10, where the 7.5-year PCSS rates were 99%, 97%, 95%, 91%, 86%, 81%, and 78% and 7.5-year OS rates were 83%, 76%, 72%, 67%, 66%, 58%, and 54%, respectively. PCSS differences for sequential score increases were all significant on univariate analyses (all P<0.05). In sequential multivariate analyses of PCSS accounting for age, prostate-specific antigen, T stage, year, marital status, race, and tumor registry, the identified GS stratifications remained significant (all P<0.05), with the exception of GS 8 w/P5 vs. 9 (P = 0.11). In overall multivariate analyses, the identified GS stratifications represented the strongest prognostic factor for survival. Subgroup analyses demonstrated that presence of any P5 was an independent prognostic factor for survival.ConclusionIn the largest reported survival analysis of Gleason stratifications, biopsy-assigned GS 6, 3+4, 4+3, 4+4, 8 w/P5, 9, and 10 represented sequential prognostic factors for survival in patients managed with definitive EBRT. 相似文献
36.
Delaram Shakoor Cesar de Cesar Netto Gaurav K Thawait Scott J Ellis Martinus Richter Lew C Schon Shadpour Demehri 《Foot and Ankle Surgery》2021,27(2):201-206
BackgroundOptimal characterization of Adult acquired flatfoot deformity (AAFD) on two-dimensional radiograph can be challenging. Weightbearing Cone Beam CT (CBCT) may improve characterization of the three-dimensional (3D) structural details of such dynamic deformity. We compared and validated AAFD measurements between weightbearing radiograph and weightbearing CBCT images.Methods20 patients (20 feet, right/left: 15/5, male/female: 12/8, mean age: 52.2) with clinical diagnosis of flexible AAFD were prospectively recruited and underwent weightbearing dorsoplantar (DP) and lateral radiograph as well as weightbearing CBCT. Two foot and ankle surgeons performed AAFD measurements at parasagittal and axial planes (lateral and DP radiographs, respectively). Intra- and Inter-observer reliabilities were calculated by Intraclass correlation (ICC) and Cohen’s kappa. Mean values of weightbearing radiograph and weightbearing CBCT measurements were also compared.ResultsExcept for medial-cuneiform-first-metatarsal-angle, adequate intra-observer reliability (range:0.61?0.96) was observed for weightbearing radiographic measurements. Moderate to very good interobserver reliability between weightbearing radiograph and weightbearing CBCT measurements were observed for the following measurements: Naviculocuneiform-angle (ICC:0.47), Medial-cuneiform-first-metatarsal-gapping (ICC:0.58), cuboid-to-floor-distance (ICC:0.68), calcaneal-inclination-angle(ICC:0.7), axial Talonavicular-coverage-angle(ICC:0.56), axial Talus-first-metatarsal-angle(ICC:0.62). Comparing weightbearing radiograph and weightbearing CBCT images, statistically significant differences in the mean values of parasagittal talus-first-metatarsal-angle, medial-cuneiform-first-metatarsal-angle, medial-cuneiform-to-floor-distance and navicular-to-floor-distance was observed (P < 0.05).ConclusionModerate to very good correlation was observed between certain weightbearing radiograph and weightbearing CBCT measurements, however, significant difference was observed between a number of AAFD measurements, which suggest that 2D radiographic evaluation could potentially underestimate the severity of AAFD, when compared to 3D weightbearing CT assessment. 相似文献
37.
电子束CT冠状动脉钙化积分与冠状动脉病变严重程度的相关研究 总被引:4,自引:1,他引:4
目的 探讨冠状动脉钙化 (CAC)程度与冠状动脉病变严重性之间的关系。材料与方法 95例同期行冠状动脉造影(CAG)及电子束 CT(EBCT)检查者 ,根据 CAG血管狭窄程度和病变累及支数 ,分成正常 /轻微病变组 (n=42 ,A/ B组 )和显著病变组 (n=5 3,F组 ) ,并细分为正常血管 (n=2 4,A组 ) ,轻微病变 ((n=18,B组 ) ,单支病变 (n=2 1,C组 ) ,2支病变 (n=15 ,D组 )和 3支病变 (n=17,E组 )各亚组。根据管腔狭窄百分比再进一步分出 95 0个血管段 ,逐个血管段与 EBCT进行对比分析。其中无狭窄血管段 735个 ,狭窄介于 0~ 5 0 %之间者 79段 ,5 0 %~ 75 %者 34段 ,狭窄≥ 75 %者 10 2段。结果 (1)血管病变支数与 CAC积分之间的关系 :A/ B组 CAC积分值明显低于 F组 (45 .1± 16 5 .1vs35 9.4± 5 0 5 .3,P<0 .0 0 0 1) ;A/ B组 CAC积分的平方根值 (3.33± 5 .91)也明显低于 C组 (9.33± 9.2 1)、D组 (12 .97± 9.16 )、E组 (2 2 .5 2± 14.17) ,P均 <0 .0 5 ,E组与 C组、D组之间也存在差别 ,但 C组和 D组之间无差别 (P>0 .0 5 ) ;A组 CAC积分的平方根值 (1.2 7± 1.2 5 )与 C组、D组、E组之间均有显著差别 (P<0 .0 5 ) ,但与 B组 (6 .0 8± 8.2 5 )之间无差别 (P>0 .0 5 )。 (2 )冠状动脉血管段狭窄程度与 CAC积分之间 相似文献
38.
BACKGROUND: The relative importance of surgery within multimodality regimens commonly used to treat advanced sinonasal malignancies remains unknown. METHODS: One hundred two patients with locally advanced sinonasal cancers treated with proton beam radiation therapy with or without surgery were retrospectively reviewed. Extent of surgery and outcome variables of local control, disease-free survival, and overall survival were evaluated. Patterns of failure were also assessed. RESULTS: Extent of surgery correlated with disease-free survival and overall survival rates. Local control rate, however, was independent of the degree of surgical resection achieved. Overall, treatment failure most commonly resulted from distant metastases, which occurred in 30% of patients and also correlated with extent of surgical resection. Tumor type-specific outcomes reveal differences associated with the extent of surgery achieved. CONCLUSION: High-dose radiotherapy with proton beam resulted in excellent local control rates in patients with locally advanced sinonasal cancer, irrespective of the extent of surgery. Complete resection, however, was predictive of improved disease-free survival and decreased rate of distant metastasis. 相似文献
39.
Objectives: The aim of the present prospective clinical study was to evaluate the match between the positions and axes of the virtually planned and the placed implants using laboratory‐based surgical guides generated from cone beam computed tomography (CBCT). Materials and methods: A total of 132 implants were placed with the aid of 3D‐based transfer templates in 52 consecutive partially edentulous patients between April 2008 and March 2010. After individual adaptation of the scan templates and CBCT scanning, the acquired data for virtual implant planning and simulation were processed using the med3D software program. After finalizing the virtual placement of the implants the radiographic templates were converted into operative guides containing titanium sleeves for cavity preparation. Preoperative planning was merged with postoperative CBCT data to identify linear and angular deviations between virtually planned and placed implants. Results: Compared with the planned implants the installed implants showed linear deviations in the median at the neck and apex of 0.27 mm (range 0.01–0.97 mm), and of 0.46 mm (range 0.03–1.38 mm), respectively. The angle deviation was 1.84° in median, with a range of 0.07–6.26°. The extent of deviation depends on the size of the tooth gap and the distribution of the remaining teeth. Conclusion: The results of this study suggested that laboratory‐fabricated surgical guides using CBCT data may be reliable in implant placement under prosthodontic considerations in partial edentulism. To cite this article: Behneke A, Burwinkel M, Knierim K, Behneke N. Accuracy assessment of cone beam computed tomography‐derived laboratory‐based surgical templates on partially edentulous patients.Clin. Oral Impl. Res. 23 , 2012; 137–143. doi: 10.1111/j.1600‐0501.2011.02176.x 相似文献
40.