INESC TEC, Campus da Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
Breast Unit, Champalimaud Clinical Center, Avenida de Brasília, 1400-038 Lisboa, Portugal.
Comput Med Imaging Graph. 2019 Oct;77:101648. doi: 10.1016/j.compmedimag.2019.101648. Epub 2019 Aug 18.
The deep inferior epigastric artery perforator (DIEAP) flap is the most common free flap used for breast reconstruction after a mastectomy. It makes use of the skin and fat of the lower abdomen to build a new breast mound either at the same time of the mastectomy or in a second surgery. This operation requires preoperative imaging studies to evaluate the branches - the perforators - that irrigate the tissue that will be used to reconstruct the breast mound. These branches will support tissue viability after the microsurgical ligation of the inferior epigastric vessels to the receptor vessels in the thorax. Usually through a computed tomography angiography (CTA), each perforator is manually identified and characterized by the imaging team, who will subsequently draw a map for the identification of the best vascular support for the reconstruction. In the current work we propose a semi-automatic methodology that aims at reducing the time and subjectivity inherent to the manual annotation. In 21 CTAs from patients proposed for breast reconstruction with DIEAP flaps, the subcutaneous region of each perforator was extracted, by means of a tracking procedure, whereas the intramuscular portion was detected through a minimum cost approach. Both were subsequently compared with the radiologist manual annotation. Results showed that the semi-automatic procedure was able to correctly detect the course of the DIEAPs with a minimum error (average error of 0.64 and 0.50 mm regarding the extraction of subcutaneous and intramuscular paths, respectively), taking little time to do so. The objective methodology is a promising tool in the automatic detection of perforators in CTA and can contribute to spare human resources and reduce subjectivity in the aforementioned task.
腹壁下动脉穿支（DIEAP）皮瓣是乳房切除术后进行乳房重建最常用的游离皮瓣。它利用下腹的皮肤和脂肪来构建新的乳房丘，既可以在乳房切除术的同时进行，也可以在第二次手术中进行。该手术需要术前影像学研究来评估为重建乳房丘而使用的组织的分支 - 穿支。这些分支将在腹壁下血管的显微结扎到胸腔内受体血管后支持组织的存活。通常通过计算机断层血管造影（CTA），每个穿支都由成像团队手动识别和描述，随后他们会绘制一张地图，以确定重建的最佳血管支持。在当前的工作中，我们提出了一种半自动方法，旨在减少手动注释固有的时间和主观性。在 21 名拟行 DIEAP 皮瓣乳房重建的患者的 CTA 中，通过跟踪程序提取每个穿支的皮下区域，而通过最小成本方法检测到肌内部分。然后将两者与放射科医生的手动注释进行比较。结果表明，半自动程序能够以较小的误差（提取皮下和肌内路径的平均误差分别为 0.64 和 0.50 毫米）正确地检测 DIEAP 的行程。该客观方法是 CTA 中穿支自动检测的有前途的工具，可以节省人力资源并减少上述任务中的主观性。
