Saved in:
Bibliographic Details
Main Authors: Kheradmand, Pejman, Yamamoto, Kent K., Webster, Emma, Sowards, Keith, Hatheway, Gianna, Jackson, Katharine L., Zani Jr., Sabino, Raffi, Julie A., Ayala-Peacock, Diandra N., Silva, Scott R., Bertram, Joanna Deaton, Chitalia, Yash
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2601.13529
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916014963294208
author Kheradmand, Pejman
Yamamoto, Kent K.
Webster, Emma
Sowards, Keith
Hatheway, Gianna
Jackson, Katharine L.
Zani Jr., Sabino
Raffi, Julie A.
Ayala-Peacock, Diandra N.
Silva, Scott R.
Bertram, Joanna Deaton
Chitalia, Yash
author_facet Kheradmand, Pejman
Yamamoto, Kent K.
Webster, Emma
Sowards, Keith
Hatheway, Gianna
Jackson, Katharine L.
Zani Jr., Sabino
Raffi, Julie A.
Ayala-Peacock, Diandra N.
Silva, Scott R.
Bertram, Joanna Deaton
Chitalia, Yash
contents Cervical cancer accounts for a significant portion of the global cancer burden among women. Interstitial brachytherapy (ISBT) is a standard procedure for treating cervical cancer; it involves placing a radioactive source through a straight hollow needle within or in close proximity to the tumor and surrounding tissue. However, the use of straight needles limits surgical planning to a linear needle path. We present the OncoReach stylet, a handheld, tendon-driven steerable stylet designed for compatibility with standard ISBT 15- and 13-gauge needles. Building upon our prior work, we evaluated design parameters like needle gauge, spherical joint count and spherical joint placement, including an asymmetric disk design to identify a configuration that maximizes bending compliance while retaining axial stiffness. Free space experiments quantified tip deflection across configurations, and a two-tube Cosserat rod model accurately predicted the centerline shape of the needle for most trials. The best performing configuration was integrated into a reusable handheld prototype that enables manual actuation. A patient-derived, multi-composite phantom model of the uterus and pelvis was developed to conduct a pilot study of the OncoReach steerable stylet with one expert user. Results showed the ability to steer from less-invasive, medial entry points to reach the lateral-most targets, underscoring the significance of steerable stylets.
format Preprint
id arxiv_https___arxiv_org_abs_2601_13529
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The OncoReach Stylet for Brachytherapy: Design Evaluation and Pilot Study
Kheradmand, Pejman
Yamamoto, Kent K.
Webster, Emma
Sowards, Keith
Hatheway, Gianna
Jackson, Katharine L.
Zani Jr., Sabino
Raffi, Julie A.
Ayala-Peacock, Diandra N.
Silva, Scott R.
Bertram, Joanna Deaton
Chitalia, Yash
Robotics
Cervical cancer accounts for a significant portion of the global cancer burden among women. Interstitial brachytherapy (ISBT) is a standard procedure for treating cervical cancer; it involves placing a radioactive source through a straight hollow needle within or in close proximity to the tumor and surrounding tissue. However, the use of straight needles limits surgical planning to a linear needle path. We present the OncoReach stylet, a handheld, tendon-driven steerable stylet designed for compatibility with standard ISBT 15- and 13-gauge needles. Building upon our prior work, we evaluated design parameters like needle gauge, spherical joint count and spherical joint placement, including an asymmetric disk design to identify a configuration that maximizes bending compliance while retaining axial stiffness. Free space experiments quantified tip deflection across configurations, and a two-tube Cosserat rod model accurately predicted the centerline shape of the needle for most trials. The best performing configuration was integrated into a reusable handheld prototype that enables manual actuation. A patient-derived, multi-composite phantom model of the uterus and pelvis was developed to conduct a pilot study of the OncoReach steerable stylet with one expert user. Results showed the ability to steer from less-invasive, medial entry points to reach the lateral-most targets, underscoring the significance of steerable stylets.
title The OncoReach Stylet for Brachytherapy: Design Evaluation and Pilot Study
topic Robotics
url https://arxiv.org/abs/2601.13529