A low cost training phantom model for radio-guided localization techniques in occult breast lesions

Construction of Low-Cost Simulators for Training in Minimally Invasive Breast Procedures

Objective

The aim of this work was to describe a technique for building low-cost simulators for training in minimally invasive breast procedures guided by ultrasound (US) and stereotactic mammography (MMG), focusing mainly on training medical professionals studying related areas.

Materials and Methods

Low-cost phantoms were developed using organic structures that mimic breast tissue, such as chicken breast and eggplant, and materials that simulate breast lesions. A step-by-step description of the preparation and use of these simulators was made, enabling the reproducibility of the technique by the physicians in training themselves.

Results

The low-cost phantoms showed a high degree of echogenic and radiological similarity with human breast tissue, allowing adequate training in minimally invasive procedures.

Conclusion

It was possible to build low-cost phantoms that allow training in US- and stereotactic MMG-guided minimally invasive breast procedures.

A Low-cost model of breast biopsy for the training of surgical residents during COVID-19 pandemic

We describe a low-cost simulation model for teaching core needle biopsy to surgical trainees in Low- and Middle-income countries (LMICs). Pre-session and post-session surveys showed that correct core sampling (ability to hit the beetroot) after training was 91.4% compared to 75.7% before demonstration and improved adequacy (68.5% before v. 85.7% after). This low-cost model using locally available products is designed to simulate a palpable breast lump and can easily be incorporated into surgical training in LMICs, where a palpable breast lump is the commonest presentation of breast cancer.

Imaging properties of 3D printed breast phantoms for lesion localization and Core needle biopsy training

Background

Breast cancer is the most commonly diagnosed malignancy in females and frequently requires core needle biopsy (CNB) to guide management. Adequate training resources for CNB suffer tremendous limitations in reusability, accurate simulation of breast tissue, and cost. The relatively recent advent of 3D printing offers an alternative for the development of breast phantoms for training purposes. However, the feasibility of this technology for the purpose of ultrasound (US) guided breast intervention has not been thoroughly studied.

Methods

We designed three breast phantom models that were printed in multiple resins available through Stratasys, including VeroClear, TangoPlus and Tissue Matrix. We also constructed several traditional breast phantoms using chicken breast and Knox gelatin for comparison. These phantoms were compared side-by-side for ultrasound penetrance, simulation of breast tissue integrity, anatomic accuracy, reusability, and cost.

Results

3D printed breast phantoms were more anatomically accurate models than traditional breast phantoms. The chicken breast phantom provided acceptable US beam penetration and material hardness for simulation of human breast tissue integrity. Sonographic image quality of the chicken breast phantom was the most accurate overall. The gelatin-based phantom also had acceptable US beam penetration and image quality; however, this material was too soft and poorly simulated breast tissue integrity. 3D printed phantoms were not visible under US.

Conclusions

There is a large unmet need for a printable material that is truly compatible with multimodality imaging for breast and other soft tissue intervention. Further research is warranted to create a realistic, reusable and affordable material to 3D print phantoms for US-guided intervention training.

Comparison of Radio-guided Occult Lesion Localization (ROLL) and Magnetic Occult Lesion Localization (MOLL) for Non-palpable Lesions: A Phantom Model Study

BACKGROUND

Localization of nonpalpable breast cancers can be achieved with several techniques. We sought to compare radio-guided localization (ROLL) and magnetic tracer localization (MOLL) techniques by using a phantom model we previously developed, which can provide an accurate simulation for excision of nonpalpable breast lesions.

MATERIALS AND METHODS

We designed 20 phantom models (10 MOLL, 10 ROLL group) for localization. A handheld gamma probe for the ROLL group and a manual magnetometer (SentiMag) for the MOLL group were used to test the ability of the modality to detect olives in turkey breasts. The excision time for each procedure, specimen size, and weight of the specimens removed from the turkey breasts were recorded.

RESULTS

Both techniques resulted in 100% retrieval of the lesions. There was no difference between the groups in the duration of operative excision, specimen weight, or specimen volume.

CONCLUSION

This experimental trial found similar success rates for ROLL and MOLL in localization of occult lesions using the turkey breast phantom model. MOLL can be performed in clinics without the need for a nuclear medicine team and radiation safety procedures.

Detection and Removal of Ceramic Clip Markers from Breast Tissue by Ultrasound-Guided, Vacuum-Assisted Minimally Invasive Biopsy in a Turkey Breast Model

This article explores the ability of sonographically guided, vacuum-assisted minimally invasive biopsy (VAB) to detect and remove ceramic clip markers from breast tissue. This is a feasibility pre-study for a clinical study using vacuum-assisted biopsy to predict pathologic complete response of breast cancer. Twenty-six ceramic clip markers were placed in five turkey breasts. Clip markers were then detected sonographically and removed using VAB by experienced physicians. Quality of visibility was graded by the performing doctors. The specimens were examined macroscopically to see if they contained the clip marker. The main outcome measure was the accuracy of VAB to detect and remove the clip marker. The VAB device was inspected for any damage possibly caused by hitting the clip marker. The clip markers were detected in 25 cases (96.2%). Twenty clip markers (76.9%) were removed completely by VAB and five (19.2%) were partially removed. One clip marker (3.8%) was not removed. On average, detection of the clip marker took 67 s and the biopsy took 178 s. Quality of visibility was mostly graded as very good (14 cases/53.8%) or good (nine cases/34.6%), and in all of these cases the clip marker was at least partially removed. The clip marker was visible and removed in the vast majority of the cases. VAB is able to remove the clip marker in integrity without causing damage to the system.