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1.
以上海市胸科医院为例,从总体架构、智能规则库、模型构建和计算等方面阐述基于智能分配规则的医院检查预约平台建设,选取对照组和观察组对平台使用前后预约情况进行对比,结果表明该平台有助于缩短检查等候时间,优化检查预约流程,提升患者满意度。  相似文献   
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翁星 《现代肿瘤医学》2022,(16):2995-2998
目的:评估剂量计算网格和γ评估标准对三维晶格放疗(lattice radiotherapy,LRT)剂量验证的影响,并确定合适的剂量计算网格和γ评估标准。方法:回顾性选取14例行LRT放疗的肿瘤患者计划,并移植到Delta4三维剂量验证模体上,使用4种剂量计算网格(1 mm、1.5 mm、2 mm和2.5 mm)创建验证计划。在4种评估标准(2%/2 mm、2%/3 mm、3%/2 mm和3%/3 mm)下进行剂量验证并获得γ通过率。最后,使用Kruskal-Wallis检验分析数据。结果:2%/2 mm和3%/2 mm评估标准的γ通过率低于2%/3 mm和3%/3 mm评估标准,2 mm和2.5 mm计算网格的γ通过率低于1 mm和1.5 mm计算网格(P<0.05)。结论:剂量计算网格和γ评估标准影响了LRT计划剂量验证中γ通过率的准确性,LRT验证计划宜采用1.5 mm或更小的计算网格和3%/2 mm或更严格的γ评估标准。  相似文献   
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目的:运用新型光学生物测量仪IOL Master 700测量白内障超声乳化手术前后眼部生物学参数的变化,并探讨人工晶状体(IOL)屈光度数计算公式的选择。

方法:前瞻性研究。收集2021-01/06在苏州大学附属第一医院就诊的白内障患者52例57眼。术前和术后3mo使用IOL Master 700完成眼轴长度(AL)、前房深度(ACD)、角膜曲率(Km)的测量并分析。对不同IOL公式计算时预留的目标屈光值与术后3mo全自动验光仪实际屈光值结果进行比较并分析。

结果:手术前后测量的AL平均值分别为24.20±1.86、24.09±1.86mm,术后AL缩短了0.11mm; ACD值分别为3.08±0.44、4.55±0.36mm(P<0.001),术后ACD加深1.49mm; Km值分别为44.14±1.86、44.14±1.82D(P>0.05)。术前选用Barrett Universal Ⅱ公式所测结果的屈光误差最小,其次是Holladay Ⅱ及SRK/T公式,Holladay Ⅰ公式所测结果的误差最大(P<0.05)。

结论:白内障术后AL缩短以及ACD加深,度数测算时可考虑增加0.1mm的校正因子。IOL屈光度数计算公式中Barrett Universal Ⅱ公式预测性最佳,其次是Holladay Ⅱ及SRK/T公式。  相似文献   

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Molecular radiotherapy is a rapidly developing field with new vector and isotope combinations continually added to market. As with any radiotherapy treatment, it is vital that the absorbed dose and toxicity profile are adequately characterised. Methodologies for absorbed dose calculations for radiopharmaceuticals were generally developed to characterise stochastic effects and not suited to calculations on a patient-specific basis. There has been substantial scientific and technological development within the field of molecular radiotherapy dosimetry to answer this challenge. The development of imaging systems and advanced processing techniques enable the acquisition of accurate measurements of radioactivity within the body. Activity assessment combined with dosimetric models and radiation transport algorithms make individualised absorbed dose calculations not only feasible, but commonplace in a variety of commercially available software packages. The development of dosimetric parameters beyond the absorbed dose has also allowed the possibility to characterise the effect of irradiation by including biological parameters that account for radiation absorbed dose rates, gradients and spatial and temporal energy distribution heterogeneities. Molecular radiotherapy is in an exciting time of its development and the application of dosimetry in this field can only have a positive influence on its continued progression.  相似文献   
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PurposePermanent implant prostate brachytherapy plays an important role in prostate cancer treatment, but dose evaluations typically follow the water-based TG-43 formalism, ignoring patient anatomy and interseed attenuation. The purpose of this study is to investigate advanced TG-186 model-based dose calculations via retrospective dosimetric and radiobiological analysis for a new patient cohort.Methods and MaterialsA cohort of 155 patients treated with permanent implant prostate brachytherapy from The Ottawa Hospital Cancer Centre is considered. Monte Carlo (MC) dose calculations are performed using tissue-based virtual patient models. Dose–volume histogram (DVH) metrics (target, organs at risk) are extracted from 3D dose distributions and compared with those from calculations under TG-43 assumptions (TG43). Equivalent uniform biologically effective dose and tumor control probability are calculated.ResultsFor the target, D90 (V100) is 136.7 ± 20.6 Gy (85.8% ± 7.8%) for TG43 and 132.8 ± 20.1 Gy (84.1% ± 8.2%) for MC; D90 is 3.0% ± 1.1% lower for MC than TG43. For organs at risk, MC D1cc = 104.4 ± 27.4 Gy (TG43: 106.3 ± 28.3 Gy) for rectum and 80.8 ± 29.7 Gy (TG43: 78.4 ± 28.4 Gy) for bladder; D1cc = 185.9 ± 30.2 Gy (TG43: 191.1 ± 32.0 Gy) for urethra. Equivalent uniform biologically effective dose and tumor control probability are generally lower when evaluated using MC doses. The largest dosimetric and radiobiological discrepancies between TG43 and MC are for patients with intraprostatic calcifications, for whom there are low doses (cold spots) in the vicinity of calcifications within the target, identified with MC but not TG43.ConclusionsDVH metrics and radiobiological indices evaluated with TG43 are systematically inaccurate by upward of several percent compared with MC patient-specific models. Mean cohort DVH metrics and their MC:TG43 variances are sensitive to patient cohort and clinical practice, underlining the importance of further retrospective MC studies toward widespread clinical adoption of advanced model-based dose calculations.  相似文献   
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AIM: To evaluate the accuracy of three commonly used biometric formulae across different axial lengths (ALs) at one United States Veterans Affairs teaching hospital. METHODS: A retrospective chart review was conducted from November 2013 to May 2018. One eye of each patient who underwent cataract surgery with a monofocal intraocular lens (IOL) was included. The range of postoperative follow-up period was from 3wk to 4mo. The Holladay 2, Barrett Universal II, and Hill-Radial Basis Function (Hill-RBF) formulae were used to predict the postoperative refraction for all cataract surgeries. For each formula, we calculated the prediction errors [including mean absolute prediction error (MAE)] and the percentage of eyes within ±0.25 diopter (D) and ±0.5 D of predicted refraction. We performed subgroup analyses for short (AL<22.0 mm), medium (AL 22.0-25.0 mm), and long eyes (AL>25.0 mm). RESULTS: A total of 1131 patients were screened, and 909 met the inclusion criteria. Resident ophthalmologists were the primary surgeons in 710 (78.1%) cases. We found no statistically significant difference in predictive accuracy among the three formulae over the entire AL range or in the short, medium, and long eye subgroups. Across the entire AL range, the Hill-RBF formula resulted in the lowest MAE (0.384 D) and the highest percentage of eyes with postoperative refraction within ±0.25 D (42.7%) and ±0.5 D (75.5%) of predicted. All three formulae had the highest MAEs (>0.5 D) and lowest percentage within ±0.5 D of predicted refraction (<55%) in short eyes. CONCLUSION: In cataract surgery patients at our teaching hospital, three commonly used biometric formulae demonstrate similar refractive accuracy across all ALs. Short eyes pose the greatest challenge to predicting postoperative refractive error.  相似文献   
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目的:评估Barrett Universal II计算公式预测三焦点人工晶状体(IOL,AT Lisa tri.839MP)屈光度的准确性,并与其他5种IOL计算公式(Haigis、HofferQ、SRK/T、SRKII和Holladay1)进行对比。方法:前瞻性临床研究。选择2016年12月至2018年8月于武汉爱尔眼科医院行飞秒激光辅助超声乳化白内障吸除联合三焦点IOL植入术的患者。术前使用Lenstar LS 900进行光学生物测量,并通过该仪器内置的其中6种IOL计算公式预测术后屈光度,IOL优化常数取自ULIB网站。随访至术后3个月行主觉验光,比较各IOL计算公式平均绝对屈光误差(MAE)的差异,并对各公式绝对屈光误差中值 (MedAE)、绝对屈光误差最大值(MaxAE)以及术后屈光误差在±0.5 D、±1.0 D和±2.0 D范围内患眼的百分比进行评估比较。数据采用Kruskal-Wallis H检验进行分析。结果:本研究最终纳入患者 55例(78眼)。根据各公式MAE值由小到大排序,依次为Barrett universal II(0.332 D)、SRK/T(0.420 D)、 Haigis(0.480 D)、Holladay1(0.607 D),HofferQ(0.626 D)以及SRKII(0.822 D)。各公式MAE差异具有统计学意义(P<0.001)。Barrett Universal II公式中MaxAE小于其他IOL计算公式。术后屈光误差在 ±0.5 D、±1.0 D以及±2.0 D范围内患眼所占百分比,Barrett Universal II公式最高,分别为73%、94.8% 以及100%。结论:Barrett Universal II、SRK/T、Haigis公式能更准确地预测患者术后实际屈光结果。因此,对于植入三焦点IOL的患者我们推荐使用Barrett Universal II、SRK/T或者Haigis公式。  相似文献   
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