IV Contrast-Enhanced Cone Beam Computed Tomography (CBCT) in Radiotherapy

Pilot Study of Intravenous Contrast-Enhanced Cone Beam Computed Tomography (CT) in Patients Receiving Radiotherapy

The purpose of this study is to find out if giving intravenous (IV) contrast (a liquid that helps with the visibility of organs and blood vessels that is given through the vein with the use of a hollow needle) during a Cone Beam Computed Tomography (CBCT- a type of computerized X-ray) can help people who have image guided radiation therapy (IGRT) for the treatment of abdominal and pelvic tumors.

The goal of this pilot study is to determine the feasibility and utility of administering IV contrast during a Cone Beam Computed Tomography (CBCT) in subjects who have image guided radiation therapy (IGRT) for the treatment of abdominal and pelvic tumors. Participant duration is one visit.

Subjects will be required to fast for at least 2 hours prior to study procedures, as determined by the treating physician based on the site to be irradiated. An 18- to 22-gauge peripheral IV will be placed in the subject's arm prior to being brought to clinical treatment room. The patient will be placed in position for radiotherapy as per standard of care and will be connected to IV contrast injector. Standard of care IGRT techniques will be performed to confirm correct positioning. Iodinated IV contrast will be administered and the contrast enhance cone beam CT will be initiated. Treatment will then be administered with the patient in the position determined by non-contrast cone beam CT, as per standard of care. Immediately after completion of treatment of the subject, the study physician will complete physician survey of attitude about the utility of contrast-enhanced cone beam CT.

Inclusion Criteria:

1. Subject must be greater than or equal to 18 years of age.
2. Subject must be able and willing to sign a written informed consent document.
3. Subject requiring image-guided external beam radiotherapy to abdominal or pelvic tumor with cone beam CT deemed clinically necessary by the treating physician.
4. No history of prior allergic reaction to intravenous CT contrast medium.
5. Creatinine of less than 1.9 mg/dL measured within one month prior to enrollment on the study.
6. No administration of intravenous contrast within 24 hours of administration of intravenous contrast on protocol.
7. Ability to complete New York Presbyterian Hospital iodinated contrast media administration questionnaire.
8. Negative pregnancy test for females of childbearing potential, in accordance to institutional guidelines.
9. Ability to fast for at least 2 hours prior to study procedures.
10. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-3.

Exclusion Criteria:

1. Known allergy to iohexol or any iodinated intravenous contrast medium.
2. Fluid overload that would contraindicate bolus administration of intravenous contrast.
3. Pregnant or nursing subjects.
4. Presence of single kidney or transplanted kidney
5. Acute renal failure
6. Chronic renal insufficiency, stage IV or V.
7. Administration of iodinated intravenous CT contrast medium within 24 hours of study procedures.
8. Inability to fast for at least 2 hours prior to study procedures.