Compagnone G, Angelini P, Pagan L
Servizio di Fisica Sanitaria, Policlinico S. Orsola Malpighi, Azienda Ospedaliero-Universitaria di Bologna, Via Massarenti 9, I-40138, Bologna, Italy.
Radiol Med. 2006 Apr;111(3):469-80. doi: 10.1007/s11547-006-0043-2. Epub 2006 Apr 11.
The Italian Decree of Law 187/2000 provides for many fulfilments relevant to justification and optimisation of medical exposures that can complicate the daily work of radiology departments if considered as mere legal requirements. On the contrary, this law should be regarded as a good opportunity to analyse and optimise working practices. To this end, the Emilia- Romagna Region carried out an initial assessment of medical exposures to its population in 2001 followed by a second survey taking into account new dosimetric evaluations. This paper illustrates the results of this second survey and analyses the most significant parameters in comparison with similar studies reported in the literature.
We first determined the examinations to be considered: 12 easily identifiable examinations divided into macroaggregates were selected for conventional radiography and computed tomography (CT). Hospitals of the Emilia-Romagna Region were directly asked to provide the number of examinations performed subdivided by type and grouped by nomenclature code, some technical parameters related to both examination protocol and equipment and the value of dose quantities as measured by local medical physicists.
Study of distribution of the entrance skin dose for different examinations in single hospitals showed no systematic differences in kilovoltage settings versus dose whereas the number of examinations tended to be inversely proportional to dose. These trends could be explained by the fact that in hospitals where many examinations of the same type are performed, operators, equipment and procedures are well integrated, leading to a level of specialisation that allows efficient interaction in order to deliver an "optimal dose". Analysis of the "entrance skin dosemax"/"entrance skin dosemin" ratios for various projections and comparison with literature data seem to show that a "scale factor" has a fundamental role in the variability of entrance skin dose values amongst hospitals and that "chest" examinations are the most critical, with the greatest differences in entrance skin doses.
The evaluations performed in this study show that this type of analysis heavily relies not only on the cooperation of all professionals responsible for patient radiation protection but also on the experience gained during previous surveys because data collection is a very critical process that can invalidate, if not carefully performed, all subsequent processing.
意大利第187/2000号法令规定了许多与医疗照射的正当性和优化相关的要求，如果仅将其视为法律要求，可能会使放射科的日常工作变得复杂。相反，该法律应被视为分析和优化工作实践的良好契机。为此，艾米利亚 - 罗马涅大区在2001年对其辖区内人群的医疗照射进行了初步评估，随后进行了第二次调查，并考虑了新的剂量学评估。本文阐述了第二次调查的结果，并与文献中报道的类似研究相比，分析了最重要的参数。
我们首先确定要考虑的检查项目：为传统放射摄影和计算机断层扫描（CT）选择了12项易于识别的检查项目，并将其分为宏观类别。直接要求艾米利亚 - 罗马涅大区的医院提供按类型细分并按命名代码分组的检查数量、与检查方案和设备相关的一些技术参数，以及当地医学物理师测量的剂量值。
对单个医院不同检查的入射皮肤剂量分布研究表明，千伏设置与剂量之间没有系统差异，而检查数量往往与剂量成反比。这些趋势可以通过以下事实来解释：在进行大量相同类型检查的医院中，操作人员、设备和程序配合良好，形成了一定程度的专业化，从而能够进行高效互动以提供“最佳剂量”。对各种投影的“最大入射皮肤剂量”/“最小入射皮肤剂量”比值进行分析，并与文献数据进行比较，似乎表明“比例因子”在不同医院入射皮肤剂量值的变化中起着重要作用，并且“胸部”检查最为关键，入射皮肤剂量差异最大。
本研究中的评估表明，此类分析不仅严重依赖负责患者辐射防护的所有专业人员的合作，还依赖于先前调查中获得的经验，因为数据收集是一个非常关键的过程，如果操作不当，可能会使所有后续处理无效。
