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101.
《Diagnostic and interventional imaging》2021,102(9):561-570
PurposeTo assess myocardial extracellular volume fraction (ECV) measurement provided by a single-source dual-energy computed tomography (SSDE-CT) acquisition added at the end of a routine CT examination before transcatether aortic valve implantation (TAVI) compared to cardiac magnetic resonance imaging (MRI).Materials and methodsTwenty-one patients (10 men, 11 women; mean age, 86 ± 4.9 years [SD]; age range: 71–92 years) with severe aortic stenosis underwent standard pre-TAVI CT with additional cardiac SSDE-CT acquisition 7 minutes after intravenous administration of iodinated contrast material and myocardial MRI including pre- and post-contrast T1-maps. Myocardial ECV and standard deviation (σECV) were calculated in the 16-segments model. ECV provided by SSDE-CT was compared to ECV provided by MRI, which served as the reference. Analyses were performed on a per-segment basis and on a per-patient involving the mean value of the 16-segments.ResultsECV was slightly overestimated by SSDE-CT (29.9 ± 4.6 [SD] %; range: 20.9%–48.3%) compared to MRI (29.1 ± 3.9 [SD] %; range: 22.0%–50.7%) (P < 0.0001) with a bias and limits of agreement of +2.3% (95%CI: −16.1%– + 20.6%) and +2.5% (95%CI: −2.1%– + 7.1%) for per-segment and per-patient-analyses, respectively. Good (r = 0.81 for per-segment-analysis) to excellent (r = 0.97 for per-patient-analysis) linear relationships (both P < 0.0001) were obtained. The σECV was significantly higher at SSDE-CT (P < 0.0001). Additional radiation dose from CT was 1.89 ± 0.38 (SD) mSv (range: 1.48–2.47 mSv).ConclusionA single additional SSDE-CT acquisition added at the end of a standard pre-TAVI CT protocol can provide ECV measurement with good to excellent linear relationship with MRI. 相似文献
102.
《Journal of Clinical Orthopaedics and Trauma》2019,10(2):380-386
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices. 相似文献
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104.
Ferdynand Hebal Elissa Port Catherine J. Hunter Bryan Malas Jared Green Marleta Reynolds 《Journal of pediatric surgery》2019,54(4):656-662
Background/purpose
Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.Methods
From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.Results
Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).Conclusions
WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.Level of Evidence
IV.Type of Study
Diagnostic Study. 相似文献105.
106.
目的 利用锥形束CT(cone-beam CT,CBCT)研究单侧完全性唇腭裂(unilateral cleft lip and palate,UCLP)患者前牙区牙槽骨开窗、骨开裂的发生率。方法 选取2014年6月—2017年9月就诊于中南大学湘雅二医院的UCLP患者42例(男25例,女17例)。匹配性别和年龄,纳入42例骨性Ⅲ类非唇腭裂患者为对照组。利用CBCT评估UCLP组与对照组前牙区骨开窗和骨开裂的发生率,采用SPSS 22.0软件包对数据进行统计学分析。结果 裂隙侧、非裂隙侧及对照组前牙骨开裂发生率分别为50.88%、42.39%和28.77%。UCLP组裂隙侧上颌前牙同名牙骨开裂的发生率均显著高于对照组(P<0.05),非裂隙侧上颌侧切牙骨开裂的发生率显著高于对照组(P<0.05),裂隙侧上颌中切牙骨开裂发生率显著高于非裂隙侧(P<0.05)。裂隙侧、非裂隙侧与对照组前牙区骨开裂均好发于唇侧。骨开窗的发生率在裂隙侧、非裂隙侧及对照组间无显著差异(P>0.05)。结论 在UCLP患者中,牙槽骨开窗和骨开裂较常见,临床治疗中应引起重视。 相似文献
107.
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110.
Marilyn Katz Nicole Silverstein Patrick Coll Gail Sullivan Eric M. Mortensen Adam Sachs Jeffrey B. Gross Eric Girard Joy Liang Benjamin T. Ristau Christina Stevenson Phillip P. Smith Brian D. Shames Ryan Millea Irfan Ali Constantine M. Poulos Akila B. Ramaraj Azuka Onye Otukoya David W. McFadden 《Current problems in surgery》2019,56(7):260-329