A Pilot Study Evaluating the Effect of 2D Antiscatter Grids on CBCT Image Quality

NCT04565457 | Completed Results DMC FDA Device

• 2 other identifiers: 20-1684.ccR01CA245270
• Study Type: interventional
• Target: 43
• Locations: 1 country
• Sites: 2

Brief Summary

This is Pilot study that investigates the CBCT(Cone beam computed tomography) image quality improvement provided by the 2D antiscatter grid technology. The primary objective is to assess the improvement in tissue visualization in an observer study, which will be conducted in a blinded fashion.

Conditions

Prostate Cancer; Head and Neck Cancers; Upper Abdomen Cancers

Outcome Measures

Primary Outcomes (6)

• Ratio of Standard CBCT to Research CBCT HU Error in Photon Therapy Participants

  Ratio of HU error for standard clinical CBCT (iteratively reconstructed) relative to research CBCT with 2D antiscatter grid in photon therapy participants. HU error was assessed in corresponding regions of interest, and the ratio was estimated using a linear mixed-effects model. A ratio greater than 1 would indicate higher HU error in standard CBCT than in research CBCT. A ratio less than 1 would indicate higher HU error in research CBCT than in standard CBCT.

  At time of CBCT imaging session (Day 1)

• Median Shift in Hounsfield Unit (HU) Error Between Standard CBCT and Research CBCT in Proton Therapy Participants

  Median paired shift in Hounsfield Unit (HU) error between research CBCT and standard clinical CBCT scans in participants receiving proton radiation therapy. HU error was evaluated in corresponding regions of interest in paired scans. The Hodges-Lehmann estimate of the median shift and its 95% confidence interval were calculated, and paired differences were evaluated using a Wilcoxon signed-rank test.

  At time of CBCT imaging session (Day 1)

• Ratio of Artifact Amplitude Between Standard CBCT and Research CBCT in Photon Therapy Participants

  Ratio of artifact amplitude between standard clinical CBCT (iteratively reconstructed) and research CBCT scans in participants receiving photon radiation therapy. Artifact amplitude was measured in corresponding regions of interest. The ratio of artifact amplitude between standard CBCT and research CBCT was estimated using a linear mixed-effects model. Ratio greater than 1 would indicate that standard CBCT has greater artifact amplitude than research CBCT.

  At time of CBCT imaging session (Day 1)

• Median Shift in Artifact Amplitude (Measured in Hounsfield Units) Between Standard CBCT and Research CBCT in Proton Therapy Participants

  Median paired shift in Artifact Amplitude between research CBCT and standard clinical CBCT scans in participants receiving proton radiation therapy. Artifact Amplitude error was evaluated in corresponding regions of interest in paired scans. The Hodges-Lehmann estimate of the median shift and its 95% confidence interval were calculated, and paired differences were evaluated using a Wilcoxon signed-rank test.

  At time of CBCT imaging session (Day 1)

• Ratio of Contrast-To-Noise Ratio (CNR) Between Standard CBCT and Research CBCT in Photon Therapy Participants

  Ratio of CNR between standard clinical CBCT and research CBCT scans in participants receiving photon radiation therapy. CNR was quantified in corresponding regions of interest in paired standard and research CBCT scans of each participant. The ratio of CNR between standard CBCT and research CBCT was estimated using a linear mixed-effects model.

  At time of CBCT imaging session (Day 1)

• Median Shift in Contrast to Noise Ratio (CNR) Between Standard CBCT and Research CBCT in Proton Therapy Participants

  Median paired shift in CNR between research CBCT and standard clinical CBCT scans in participants receiving proton radiation therapy. CNR was evaluated in corresponding regions of interest in paired scans. The Hodges-Lehmann estimate of the median shift and its 95% confidence interval were calculated, and paired differences were evaluated using a Wilcoxon signed-rank test.

  At time of CBCT imaging session (Day 1)

Secondary Outcomes (1)

• Accuracy of Automated Tissue Delineation in CBCT Images for Photon Therapy Participants. Difference in Dice Similarity Coefficient Between Research CBCT and Standard CBCT

  At time of CBCT imaging session.

Study Arms (1)

Participants Scanned

EXPERIMENTAL

All participants will be scanned with a CBCT system equipped with 2D antiscatter grid technology, referred to as research CBCT. Each participant will also be scanned with a standard clinical CBCT as part of their standard clinical care, which will serve as the baseline, or control.

Device: Research CBCT

Interventions

Research CBCT DEVICE

Each study participant will receive one additional CBCT scan, with 2D antiscatter grid in place. This is the only intervention in the study, referred as research CBCT scan, and it will be performed on one of the days during the participant's radiation treatment course. This additional research CBCT scan will be used strictly for the objectives of this study. It will not be used as part of the standard clinical care, such as imaging guidance of participant's radiation treatment or diagnostic purposes. To deliver participant's radiation treatment under CBCT guidance, a standard clinical CBCT scan will be acquired, as in standard clinical care protocols.

Participants Scanned

Eligibility Criteria

• Age: 18 Years - 100 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Provision to sign and date the consent form.
• Stated willingness to comply with all study procedures and be available for the duration of the study.
• Be a male or female aged 18-100.
• Participants who will be treated or are currently being treated with CBCT-guided photon therapy for prostate or prostate-bed, abdomen head and neck, or pelvic cancers, or with image-guided proton therapy for prostate or prostate bed cancer.

You may not qualify if:

• Patients who do not have the ability to lie still for the duration of his/her CBCT imaging and treatment should be excluded. If image artifacts in prior scans are deemed excessive, the patient will be excluded from the study.
• Known pregnancy. (Per SOC, a pregnancy test will be performed prior to CBCT scan on Day 1. At this time, women of child-bearing potential (WOCBP) will receive a pregnancy test to re-confirm eligibility).
• Women of child-bearing potential are described as:
• Age 55 or younger who have not had a negative pregnancy test within 3 days. This excludes patients who have had tubal ligation or are already post-menopausal.

Sponsors & Collaborators

• University of Colorado, Denver: lead
• National Cancer Institute (NCI): collaborator

Study Sites (2)

University of Colorado Hospital

Aurora, Colorado, 80045, United States

Location

University of Florida Health Proton Therapy Institute

Jacksonville, Florida, 32206, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms; Head and Neck Neoplasms

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Limitations and Caveats

Research CBCT scans were performed while participants were free breathing. When organ motion was present in the scan volume, image artifacts caused by motion might have affected the values of image quality metrics in both research and standard of care CBCT scans.

Results Point of Contact

• Title: Cem Altunbas, PhD
• Organization: University of Colorado Cancer Center

cem.altunbas@cuanschutz.edu

7208480098

Study Officials

• Cem Altunbas, PhD

  University of Colorado, Denver

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Single arm study

Study Record Dates

• First Submitted: September 18, 2020
• First Posted: September 25, 2020
• Study Start: April 21, 2023
• Primary Completion: May 28, 2025
• Study Completion: May 28, 2025
• Last Updated: May 6, 2026
• Results First Posted: May 6, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)