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

Study Overview
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Brief Summary
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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.

Detailed Description
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This is a single arm study, where 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. Thus, the image quality improvement in research CBCT will assessed with respect to standard clinical CBCT.

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

Conditions
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Prostate Cancer, Head and Neck Cancers, Upper Abdomen Cancers

Intervention / Treatment
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* Device: Research CBCT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 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 with CBCT-guided photon therapy for upper abdomen, prostate, head and neck cancers, or with CBCT-guided proton therapy for prostate cancer. Exclusion Criteria: Metallic implants in the CBCT scan volume, such as hip prostheses or spine stabilization hardware. Dental implants, filings, or fiducial markers may be acceptable, and the decision for inclusion/exclusion will be on a case-by-case basis, by reviewing prior CT images of the study candidate. Patient's prior CT images will be reviewed by the PI. 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, 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 will receive a pregnancy test to reconfirm eligibility).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: Single arm study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Participants Scanned<br>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<br>* 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.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in tissue visualization in CBCT images | Inter-observer similarity of delineated anatomical structures as measured by the Conformity Index (CI) similarity metrics. | 4 years | 
| Change in tissue visualization in CBCT images | Inter-observer similarity of delineated anatomical structures as measured by the Hausdorff distance (HD) similarity metrics. | 4 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of tissue delineation in CBCT images by auto-segmentation software. | Similarity of anatomical structures delineated by autosegmentation software and expert observers, as measured by CI and HD metrics. | 4 years |