The use of a three-dimensional print model of an aortic arch to plan a complex percutaneous intervention in a patient with coarctation of the aorta

Clinical situations for which 3D Printing is considered an appropriate representation or extension of data contained in a medical imaging examination: vascular conditions

BACKGROUND

Medical three-dimensional (3D) printing has demonstrated utility and value in anatomic models for vascular conditions. A writing group composed of the Radiological Society of North America (RSNA) Special Interest Group on 3D Printing (3DPSIG) provides appropriateness recommendations for vascular 3D printing indications.

METHODS

A structured literature search was conducted to identify all relevant articles using 3D printing technology associated with vascular indications. Each study was vetted by the authors and strength of evidence was assessed according to published appropriateness ratings.

RESULTS

Evidence-based recommendations for when 3D printing is appropriate are provided for the following areas: aneurysm, dissection, extremity vascular disease, other arterial diseases, acute venous thromboembolic disease, venous disorders, lymphedema, congenital vascular malformations, vascular trauma, vascular tumors, visceral vasculature for surgical planning, dialysis access, vascular research/development and modeling, and other vasculopathy. Recommendations are provided in accordance with strength of evidence of publications corresponding to each vascular condition combined with expert opinion from members of the 3DPSIG.

CONCLUSION

This consensus appropriateness ratings document, created by the members of the 3DPSIG, provides an updated reference for clinical standards of 3D printing for the care of patients with vascular conditions.

3D printing in aortic endovascular therapies

Endovascular treatment of aortic disease, including aneurysm or dissection, is expanding at a rapid pace. Often, the specific patient anatomy in these cases is complex. Additive manufacturing, also known as three-dimensional (3D) printing, is especially useful in the treatment of aortic disease, due to its ability to manufacture physical models of complex patient anatomy. Compared to other surgical procedures, endovascular aortic repair can readily exploit the advantages of 3D printing with regard to operative planning and preoperative training. To date, there have been numerous uses of 3D printing in the treatment of aortic pathology as an adjunct in presurgical planning and as a basis for training modules for fellows and residents. In this review, we summarize the current uses of 3D printing in the endovascular management of aortic disease. We also review the process of producing these models, the limitations of their applications, and future directions of 3D printing in this field.

Embolization using patient-specific vascular models created by a 3D printer for difficult cases: a report of two cases

With the widespread use of three-dimensional printers, organ models created by these printers are now being used in the medical field for preoperative planning of surgeries. In this article, we report two cases in which embolization was expected to be difficult, and the three-dimensional printer-based vascular modeling was helpful in planning the surgery. The first case involved an aneurysm of the splenic artery. We attempted to embolize the aneurysm but were unable to advance the catheter into the distal artery and discontinued the procedure. The second case was a perianal varicose vein, which was initially treated with percutaneous transhepatic obliteration but was recanalized and required embolization. However, we expected difficulty in selecting the inferior mesenteric vein. In both cases, the vascular models were created using a 3D printer from the patients' computed tomography images. Preoperative planning, including treatment simulation, was based on these models. The time required to print a three-dimensional vascular model was approximately 12 hours at a cost of less than $10 each. Patient-specific vascular models using a three-dimensional printer can be a simple and inexpensive tool that can increase the success of embolization in difficult cases.

Morphometric evaluation of aortic coarctation and collateral circulation using computed tomography in the adult population

Background

Analysis of morphometric details of aortic coarctation and collateral circulation using computed tomography (CT) and its impact on clinical symptoms is a perspective which is missing in the published literature.

Purpose

To perform CT-based qualitative and quantitative evaluation of aortic coarctation and collateral circulation with reference to clinical symptoms.

Material and Methods

The study comprised 2022 patients who underwent CT angiography. If aortic coarctation was seen, the patients underwent evaluation of its anatomy and associated clinical symptoms.

Results

Aortic coarctation was found in 33 patients. Follow-up (median 2476 days; range 1692–3543) was performed in 31 (94%) individuals. In this group (median age 42 years; range 30–52.5 years), median stenosis at the site of coarctation was 70% (range 58–85%) of the lumen area, with 17 (55%) patients presenting with significant (≥70%) stenosis. Patients with significant stenosis had a greater right and left internal mammary artery diameter ( P = 0.0070 and P = 0.0114, respectively) than those with mild stenosis. Patients with significant coarctation stenosis revealed hypertension and headache more commonly than those with mild stenosis (17 vs. 9, P = 0.01 and 10 vs. 2, P = 0.02), respectively. In patients who underwent intervention, a decrease in prevalence of hypertension (19 vs. 0, P = 0.008) and headache (12 vs. 3, P = 0.010) were observed in the follow-up.

Conclusion

CT enables quantitative and qualitative evaluation of aortic coarctation anatomy, including stenosis at the site of coarctation, and collateral circulation. In adult patients with aortic coarctation, the prevalence of hypertension and headache is related to the degree of stenosis at the site of coarctation and decreases after intervention.

Patient-specific three-dimensional printed heart models benefit preoperative planning for complex congenital heart disease

BACKGROUND

Preoperative planning for children with congenital heart diseases remains crucial and challenging. This study aimed to investigate the roles of three-dimensional printed patient-specific heart models in the presurgical planning for complex congenital heart disease.

METHODS

From May 2017 to January 2018, 15 children diagnosed with complex congenital heart disease were included in this study. Heart models were printed based on computed tomography (CT) imaging reconstruction by a 3D printer with photosensitive resin using the stereolithography apparatus technology. Surgery options were first evaluated by a sophisticated cardiac surgery group using CT images only, and then surgical plans were also set up based on heart models.

RESULTS

Fifteen 3D printed heart models were successfully generated. According to the decisions based on CT, 13 cases were consistent with real options, while the other 2 were not. According to 3D printed heart models, all the 15 cases were consistent with real options. Unfortunately, one child diagnosed with complete transposition of great arteries combined with interruption of aortic arch (type A) died 5 days after operation due to postoperative low cardiac output syndrome. The cardiologists, especially the younger ones, considered that these 3D printed heart models with tangible, physical and comprehensive illustrations were beneficial for preoperative planning of complex congenital heart diseases.

CONCLUSION

3D printed heart models are beneficial and promising in preoperative planning for complex congenital heart diseases, and are able to help conform or even improve the surgery options.