Point-of-care 3D printing: a low-cost approach to teaching carotid artery stenting

Accuracy and feasibility in building a personalized 3D printed femoral pseudoaneurysm model for endovascular training

BACKGROUND

The use of three-dimensional(3D) printing is broadly across many medical specialties. It is an innovative, and rapidly growing technology to produce custom anatomical models and medical conditions models for medical teaching, surgical planning, and patient education. This study aimed to evaluate the accuracy and feasibility of 3D printing in creating a superficial femoral artery pseudoaneurysm model based on CT scans for endovascular training.

METHODS

A case of a left superficial femoral artery pseudoaneurysm was selected, and the 3D model was created using DICOM files imported into Materialise Mimics 22.0 and Materialise 3-Matic software, then printed using vat polymerization technology. Two 3D-printed models were created, and a series of comparisons were conducted between the 3D segmented images from CT scans and these two 3D-printed models. Ten comparisons involving internal diameters and angles of the specific anatomical location were measured.

RESULTS

The study found that the absolute mean difference in diameter between the 3D segmented images and the 3D printed models was 0.179±0.145 mm and 0.216±0.143mm, respectively, with no significant difference between the two sets of models. Additionally, the absolute mean difference in angle was 0.99±0.65° and 1.00±0.91°, respectively, and the absolute mean difference in angle between the two sets of data was not significant. Bland-Altman analysis confirmed a high correlation in dimension measurements between the 3D-printed models and segmented images. Furthermore, the accuracy of a 3D-printed femoral pseudoaneurysm model was further tested through the simulation of a superficial femoral artery pseudoaneurysm coiling procedure using the Philips Azurion7 in the angiography room.

CONCLUSIONS

3D printing is a reliable technique for producing a high accuracy 3D anatomical model that closely resemble a patient's anatomy based on CT images. Additionally, 3D printing is a feasible and viable option for use in endovascular training and medical education. In general, 3D printing is an encouraging technology with diverse possibilities in medicine, including surgical planning, medical education, and medical device advancement.

Comparison of two-dimensional imaging to three-dimensional modeling of intrahepatic portosystemic shunts using computed tomography angiography

Computed tomography angiography (CTA) is used for the diagnosis of intrahepatic portosystemic shunts (IHPSS). When planning for transcatheter intervention, caudal vena cava (CVC) measurements are typically obtained from two-dimensional (2D) imaging to aid in stent selection. We hypothesized that clinically applicable three-dimensional (3D) IHPSS models can be generated, and CVC measurements will not differ between 2D images and 3D models. Computed tomography angiography datasets from client-owned dogs with IHPSS at the University of Georgia Veterinary Teaching Hospital from 2016 to 2022 were analyzed. Materialise Mimics 25.0 and 3-matic 17.0 were used for 3D modeling. Caudal vena cava diameters were measured in 2D dorsal and transverse planes 20 mm cranial and caudal from the shunt ostium and were compared with CVC diameters from 3D models. Length was measured in the 2D dorsal plane between midpoints of each diameter and compared to the 3D model length. Data are presented as mean (SD), and intraclass correlation coefficients were performed. Three-dimensional models were generated for 32 IHPSS (15 right-, 12 left-, and five central-divisional). Two-dimensional dorsal and transverse area-associated diameter measurements were 16.7 mm (5.6) and 15.5 mm (4.2) cranial; 14.9 mm (4.2) and 14.3 mm (3.7) caudal. Three-dimensional area-associated diameter measurements were 15.3 mm (4.4) cranial and 14.0 mm (3.6) caudal. The 2D length was 61.5 mm (7.1) compared with 3D 59.9 mm (7.2). Intraclass correlation coefficients comparing 2D and 3D diameters were all >0.80, indicating very good agreement, with good agreement (>0.60) for length. Clinically applicable 3D IHPSS models can be generated using engineering software. Measurements from 3D models are consistent with 2D planar imaging. Both 2D CTA and 3D virtual models can be utilized for preprocedural planning, depending on clinician preference.

Advanced Image Segmentation and Modeling - A Review of the 2021-2022 Thematic Series

Medical 3D printing is a form of manufacturing that benefits patient care, particularly when the 3D printed part is patient-specific and either enables or facilitates an intervention for a specific condition. Most of the patient-specific medical 3D printing begins with volume based medical images of the patient. Several digital manipulations are typically performed to prescribe a final anatomic representation that is then 3D printed. Among these are image segmentation where a volume of interest such as an organ or a set of tissues is digitally extracted from the volumetric imaging data. Image segmentation requires medical expertise, training, software, and effort. The theme of image segmentation has a broad intersection with medical 3D printing. The purpose of this editorial is to highlight different points of that intersection in a recent thematic series within 3D Printing in Medicine.