Copenhagen, Denmark
Onsite/Online

ESTRO 2022

Session Item

Implementation of new technology and techniques
Poster (digital)
Physics
A new machine learning-based clinical tool for vertebral level verification and treatment planning
Tucker Netherton, USA
PO-1652

Abstract

A new machine learning-based clinical tool for vertebral level verification and treatment planning
Authors:

Tucker Netherton1, Callistus Nguyen1, Carlos Cardenas2, Caroline Chung3, Ann Klopp3, Lauren Colbert3, Dong Joo Rhee1, Christine Peterson4, Rebecca Howell1, Ajay Aggarwal5, Hannah Simonds6, Laurence Court1

1University of Texas MD Anderson Cancer Center, Radiation Physics, Houston, USA; 2University of Alabama Birmingham , Radiation Physics, Birmingham, USA; 3University of Texas MD Anderson Cancer Center, Radiation Oncology, Houston, USA; 4University of Texas MD Anderson Cancer Center, Biostatistics, Houston, USA; 5Guy's and St. Thomas Hospital London, Radiation Oncology, London, United Kingdom; 6Stellenbosch University, Radiation Oncology, Cape Town, South Africa

Show Affiliations
Purpose or Objective

To develop a palliative treatment planning paradigm that verifies all vertebral bodies and creates a treatment plan on diagnostic and simulation CT images.

Material and Methods

Vertebrae from any CT and of any length are labeled (C1-L5) using two intendent deep learning models to mirror two different experts labeling the spine. Then, a UNet++ architecture was trained, validation, and tested so that each resulting vertebrae could be contoured using (n=220 CTs). Features from labeling and from contours were input into a random forest classifier to predict whether vertebrae were correctly labeled. This classifier was trained using CBCT, PET-CT, diagnostic, and simulation CT images (n=56 CTs, 752 contours). Autoplans were generated via scripting using auto-verified contours. Each model was combined into a framework to make a fully-automated treatment planning clinical tool. Three radiation oncologist scored plan quality on a new cohort of CT scans (n=60) on a 5-point scale. CTs varied in scan length, presence of surgical implants, imaging protocol, and metastatic burden.

Results

Accuracy for automatic labeling was 94% with < 2.2mm error. Mean Dice-Similarity Coefficient was 85.0%(cervical), 90.3%(thoracic), and 93.7%(lumbar). The random forest classifier predicted mislabeling across various CT scan types with precision-recall-AUC=0.82. All contouring and labeling errors (11/11) within treatment regions, including errors from patient plans (6/6) with atypical anatomy (e.g. T13, L6) were detected. Radiation oncologists scored 98% of simulation CT- and 92% of diagnostic CT-based plans as clinically acceptable or needing minor edits for patients with typical anatomy. End-to-end treatment planning time of the clinical tool was less than 8 minutes on average.


Conclusion

This novel method to automatically verify, contour, and plan palliative spine treatments is efficient, effective, and safe across various CT scan types.