Modelling of aortic aneurysm and aortic dissection through 3D printing

Abstract

IntroductionThe aim of this study was to assess if the complex anatomy of aortic aneurysm and aortic dissection can be accurately reproduced from a contrast‐enhanced computed tomography (CT) scan into a three‐dimensional (3D) printed model.MethodsContrast‐enhanced cardiac CT scans from two patients were post‐processed and produced as 3D printed thoracic aorta models of aortic aneurysm and aortic dissection. The transverse diameter was measured at five anatomical landmarks for both models, compared across three stages: the original contrast‐enhanced CT images, the stereolithography (STL) format computerised model prepared for 3D printing and the contrast‐enhanced CT of the 3D printed model. For the model with aortic dissection, measurements of the true and false lumen were taken and compared at two points on the descending aorta.ResultsThree‐dimensional printed models were generated with strong and flexible plastic material with successful replication of anatomical details of aortic structures and pathologies. The mean difference in transverse vessel diameter between the contrast‐enhanced CT images before and after 3D printing was 1.0 and 1.2 mm, for the first and second models respectively (standard deviation: 1.0 mm and 0.9 mm). Additionally, for the second model, the mean luminal diameter difference between the 3D printed model and CT images was 0.5 mm.ConclusionEncouraging results were achieved with regards to reproducing 3D models depicting aortic aneurysm and aortic dissection. Variances in vessel diameter measurement outside a standard deviation of 1 mm tolerance indicate further work is required into the assessment and accuracy of 3D model reproduction.

Patient-specific three-dimensional printing for pre-surgical planning in hepatocellular carcinoma treatment

“…A four-step production process was implemented to generate the patient-specific 3D liver model utilized for this study ( Figure 1) (3,6,9,10,21,24,25).…”

“…Image visualization and processing tools within this software were used to (I) apply a median filter, reducing image noise and enhancing the anatomical boundaries for accurate segmentation; (II) segment structures of interest; and (III) export the segmented data in standard tessellation language (STL) file format as required for editing and 3D printing (10,16,18,(22)(23)(24)(25). Anatomical structures that were perceived likely to affect decisions made in surgical planning included the inferior vena cava, portal vein and associated branches, hepatic veins, hepatic artery, the tumour and associated arterial supply, and the liver body (2,3,9,23).…”

Three-Dimensional Printing in Cardiovascular Disease: Verification of Diagnostic Accuracy of 3D Printed Models

“…[21][22][23][24][25] However, in a recent study, Ho et al have indicated that the variances in aortic diameter measurements between 3D printed models and 2D contrastenhanced CT images exceeded 1.0 mm, which is beyond the standard deviation of 1.0 mm. 26 This highlights the potential limitations of using anatomic landmarks to measure accuracy of 3D printed hollow models, such as heart models or aneurysmal models. By taking into account both sizes and shapes of the visceral aneurysms, the accuracy of 3D printed hollow models has been validated to further confirm the reliability of 3D printing technology.…”

“…Further, according to a recent systematic review, majority of the current studies compared 3D printed models with original source CT or MRI data, 12,[21][22][23][24] while only a few of them compared images of the scanned 3D printed models with original source imaging data (Figure 1). 25,26 Discrepancy in measuring these dimensional diameters was shown in one of the studies with the maximal difference in vessel diameter being 3.2 mm, highlighting the limited accuracy of using diameter measurements. 26 This limitation has been addressed by using a more accurate method to determine the accuracy of 3D printed models, which is the second observation from Shibata et al study.…”

“…25,26 Discrepancy in measuring these dimensional diameters was shown in one of the studies with the maximal difference in vessel diameter being 3.2 mm, highlighting the limited accuracy of using diameter measurements. 26 This limitation has been addressed by using a more accurate method to determine the accuracy of 3D printed models, which is the second observation from Shibata et al study. Authors used the Dice coefficient index, a reproducibility validation metric which is represented by the spatial overlap index.…”