衰减测量结果表明，在术中电子放射治疗或高剂量率近距离放射治疗中，使用速即纱手术补片不会影响靶区照射。

Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy.

作者信息

Sarmento Sandra, Costa Filipa, Pereira Alexandre, Lencart Joana, Dias Anabela, Cunha Luís, Sousa Olga, Silva José Pedro, Santos Lúcio

机构信息

Medical Physics Department, Portuguese Institute of Oncology, Porto, Portugal.

Medical Physics, Radiobiology and Radiation Protection Group, Research Centre, Portuguese Institute of Oncology, Porto, Portugal.

出版信息

Radiat Oncol. 2015 Jan 9;10:7. doi: 10.1186/s13014-014-0316-1.

DOI:10.1186/s13014-014-0316-1

PMID:25572977

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4293105/

Abstract

BACKGROUND

Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT.

METHODS

CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber.

RESULTS

Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR (192)Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT.

CONCLUSION

The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR (192)Ir brachytherapy.

摘要

背景

局部晚期和/或复发性直肠癌手术可辅以术中电子放射治疗（IOERT），将单剂量放射直接送达无法切除的边缘，同时保护附近敏感器官/结构。可能会发生出血，这会影响剂量分布，导致靶区照射不正确。速即纱（TS）手术贴片激活后，会在手术部位形成纤维蛋白凝块以实现止血。本研究的目的是确定TS对剂量分布的影响，并确定其是否可与IOERT联合使用。这一特性研究扩展至包括高剂量率（HDR）术中近距离放疗，其他机构有时会使用这种方法而非IOERT。

方法

获取TS贴片的CT图像进行初步特性研究。在水箱体模中进行剂量测量，使用带有圆柱形施源器硬对接系统的传统直线加速器。获得百分深度剂量（PDD）曲线，并在三种临床常用电子能量（6、9和12MeV）的剂量最大值深度处进行测量，首先不使用任何衰减器，然后使用完全覆盖IOERT施源器尖端的激活后的TS贴片。对于HDR近距离放疗，使用固体水体模和 Farmer电离室临时搭建测量装置。