Modulated Electron Bolus
Software & Hardware
I already have a 3D printer - can I use this model instead of one of Adaptiiv's validated printers?
Yes. Adaptiiv’s software is compatible with all 3D printers on the market that accept STL files.
What is the expected printer maintenance that will be required?
Printer maintenance is quite minimal in comparison to traditional fabrication methods. These tasks include, but not limited to: lubricating the print rods, exchanging the nozzles, and cleaning/replacing the glass bed.
How do you mitigate the risk of a faulty print occurring overnight when you have a treatment scheduled for the next morning?
Features within Adaptiiv’s software increase the probability of print success. For example, using the cropping feature in Adaptiiv software ensures that the print will lie flush on the print bed, improving print success. In addition, Adaptiiv provides settings for validated filaments used with printers that improve the probability of success.
What specifications does Adaptiiv choose when validating a FDM printer?
What is the average print time?
There are 5 main factors that contribute to the print time:
Smaller bolus for noses and cheeks take ~1-2 hours to print, while large chest walls could take 15 hours. Since brachytherapy applicators can be printed at <100% infill (as low as 20%), the print time decreases accordingly. Any accessories that take longer to print can be left to print overnight (or when the facility has downtime), ensuring the accessory will be ready for use during planned treatment.
Where will Adaptiiv software be installed in my Center?
Our software uses DICOM data exported from a TPS and modifies the accessory using that data. The modified data needs to be imported back to the TPS for proper dose verification. Our software is typically installed on a separate workstation from the TPS, but it’s possible to be installed on the same server as the TPS, if hardware and software requirements are met.
What type of materials are used?
3D printed bolus are created with durable, tissue-equivalent materials that hold their shape and do not degrade during treatment. Patients typically use the same 3D printed bolus for the duration of their treatment, reducing the risk of infection.
What are the capabilities of the smoothing tool within Adaptiiv’s software without going back to the TPS to manually edit the problem areas?
Any object entered into our software goes through a global smoothing operator to ensure minimal discrete stepping.
In the case of a patient’s contours or size changing during treatment, what is the process of adjusting the accessory to meet the new contours?
Our software accepts DICOM information as input. As a result, daily (or new) CBCT information can be used to create a new bolus structure if a patient’s anatomy changes.
How does Adaptiiv integrate with existing systems?
Our software converts patient DICOM data into a digital model which can be 3D printed, no matter the size or complexity. RT accessories designed in our software can be validated in the TPS ensuring that the designed accessory matches the prescribed treatment plan prior to printing.
In the case of smaller lesions that would be primarily treated using a Valencia applicator, how would Adaptiiv applicators compare in terms of treatment effectiveness?
Unlike general flat-surfaced Valencia applicators, our devices are tailored to the individual patient for more consistent placement over both small and large areas—no matter how complex.
Does Adaptiiv's software provide a warning when the angle of the trajectory may be at risk for source sticking?
Adaptiiv software automatically identifies which part of each trajectory has a minimum bend-radius less than a commissioned threshold which can be set by a user (e.g. 13mm), further minimizing the risk of a source being stuck. The software highlights those potentially problematic areas in red color where users can simply click on a specific trajectory node and drag it until the curvature radius is changed, reflecting the safety of a chosen threshold value (those areas then turn from red to yellow).
After tunnels are in the applicator, can you send it back to the TPS to plan treatment in advance without the patient being present?
Yes. In Adaptiiv software, a user can export a DICOM RT structure containing the brachy applicator with tunnels back into the TPS. When imported into the TPS, a user would need to recreate source trajectories based on the generated tunnel RT structures. Another solution is to scan the 3D-printed applicator with X-ray markers without a patient, import it
back into the TPS and co-register it with original patient CT images, and then re-create the source trajectories according to markers.
We are currently researching the possibility of exporting the source trajectory coordinates via the DICOM RT plan, upon rendering the 3D brachy-tunnels in our software. Stay tuned – more to come on this.
How does Adaptiiv’s software account for the density of PLA in the Brachytherapy TPS?
Applicators for surface brachytherapy can be printed in various percentages of infill (up to 100% which density is then close to being water-equivalent). Since the dose fall-off for surface brachytherapy applications is governed mainly by the Inverse Square Law, you can even print in infill less than 100% (e.g. 30%) to save time, depending on the radiological backscattering properties of the applicator which need to be achieved.
What are the advantages of using Adaptiiv’s software solution to create patient-specific brachytherapy applicators?
What are the advantages of using Adaptiiv software to create modulated electron bolus?
What are the benefits of using a 3D printed bolus on a patient?
If I am able to achieve acceptable dosimetry using wax bolus, then what is the value of using Adaptiiv software?
Wax bolus generally take longer to fabricate and don’t allow the users to communicate back and forth with the TPS to evaluate and recalculate dose. This process would involve the user having to place the accessory on the patient and scan for positioning which adds time to the setup process. Our software processes all key patient information from the TPS and optimizes a new bolus structure in a matter of minutes.
How do adjustments or modifications occur to the bolus design using Adaptiiv software?
Our software’s algorithms generate a custom bolus structure based on patient DICOM information imported from the TPS. No manual alterations are required.
Can't I simply contour the bolus in the TPS and then export for printing?
In a recent business case, a leading cancer center developed a modulated bolus using Eclipse software. The therapist had to adjust the bolus slice by slice to ensure that the bolus thickness aligned with the PTV. It took a total of 32 hours.
In comparison, when using our software, it took only 2 minutes to render the same design. You can even import the model back into the TPS to be reviewed and verified prior to 3D printing.
How much benefit does the reduction of air gaps really have on treatment?
Air gaps beneath conventional sheet bolus (i.e. Superflab) may cause substantial inaccuracies in delivered surface dose to the patient. Using patient-specific 3D printed bolus minimizes the risk of delivering inadequate RT treatment.
How does the simple bolus module differ from a conventional STL conversion?
Post-production modifications such as cropping and smoothing functions were added for a better fit and patient experience. Adaptiiv also allows the user to add a printable ID tag directly to the bolus. We are continually investing in new features, such as vivo dosimetry and the ability to print bolus in multiple pieces for larger or hard-to-fit areas, like the skull.
How does 3D printed bolus compare to other traditional materials such as moulding wax or jelly-based materials such as Superflab?
Bolus designed using our software uses the patient’s exact measurements and can be previewed before printing. Our software offers smoothing and cropping functions to ensure that the device is not only the best fit, but that it also has no air gaps, completely eliminating the need for additional bolus.
How accurate is 3D printed simple bolus?
In a recent study where a standard sheet bolus and 3D printed bolus were fitted to the chest wall, the occurrence of air gaps were reduced from 30% to 13% and the average maximum air gap dimension diminished from 0.5 +/− 0.3 mm to 0.3 +/− 0.3 mm. Surface dosage was within 3% for both standard sheet bolus and 3D printed bolus.
Source: Robar et al – Intrapatient study comparing 3D printed bolus versus standard vinyl gel sheet bolus for postmastectomy chest wall radiation therapy.
Can a simple bolus be created to treat a patient with their breast still intact?
Yes. 3D printed bolus created using our software incorporates all contours and shapes of the treatment area, including breast tissue.