Treating Arteriovenous Malformation With Stereotactic Radiosurgery Using CT Angiography for Treatment Planning

Study Overview
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Brief Summary
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Evaluate whether a treatment plan based on CT angiography can accurately and precisely identify the target nidus as compared to standard cerebral arteriography fused to MRI.

Detailed Description
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Stereotactic Radiosurgery is a preferable treatment option for patients with Arteriovenous malformation (AVM) that are not surgically accessible or in patients with comorbidities that make them poor surgical candidates At University of Texas Southwestern Medical Center (UTSW), investigator routinely perform interventional cerebral arteriography on the day of the SRS procedure for improved target delineation. Even though the addition of angiography is time consuming and requires multi-modality team care, this approach has allowed UTSW to treat the smallest possible target, yet achieve excellent obliteration rates of AVM with very low toxicity from the procedure. At UTSW the investigator also use CT angiogram at the treatment team's discretion to further enhance the accurate delineation of the final treatment target volume. However, it had not been routinely done due to uncertain benefit in treatment planning and a concern for renal burden from additional intravenous (IV) contrast usage. This prospective enrollment and conduct open-label, retrospective analysis study is to evaluate whether a target volume based on CT angiography can serve as a reliable substitute for a target based on interventional cerebral arteriography. Patients on this protocol will still get treated based on target generated by interventional cerebral arteriography but also receive CT angiography. If the target volume based on CT angiography are adequate compared to their invasive counterpart, future investigators may selectively omit performing interventional cerebral arteriography in the treatment planning for SRS of AVM. Use of CT angiography may lead to reduction in the risk from the procedure and cost, improve the efficiency of the treatment process ideally without compromising the success of the procedure, with greater patient comfort and satisfaction.

Official Title
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Validation Study of Treating Arteriovenous Malformation With Stereotactic Radiosurgery Using CT Angiography for Treatment Planning

Conditions
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Arteriovenous Malformations

Intervention / Treatment
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* Other: CT angiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Documented AVM with draining vein(s). Adequate renal function (within 30 days) to undergo contrast CT and interventional cerebral arteriography on the same day, as determined by treating physicians. AVM must be physically separated from the optic pathway, brainstem or spinal cord. The maximum diameter of AVM nidus must be less than 3.5 cm and/or less than 12 cc. Age ≥ 10 years. Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) at least three weeks prior and three weeks after the SRS procedure. 6.1 A female of child-bearing potential is any woman (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice) who meets the following criteria: Has not undergone a hysterectomy or bilateral oophorectomy; or Has not been naturally postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in the preceding 12 consecutive months). 6.2 Negative urine hCG test (within 30 days) for female of child-bearing potential. Ability to understand and the willingness to sign a written informed consent. Exclusion Criteria: Patients without a documented AVM. Patients with a contraindication to CT or MRI such as contrast allergy, kidney failure or implanted metal devices or foreign bodies or severe claustrophobia. Use of Nephrotoxic drugs, such as gentamycin, high-dose nonsteroidal anti-inflammatory drugs, or certain chemotherapeutic drugs within 10 days of the procedure. Recent (within 10 days) or ongoing urinary tract infection (UTI). Psychiatric illness/social situations that would limit compliance with study requirements. Patients must not be pregnant at the time of SRS treatment.

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 120 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: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patient with AVM requiring radiotherapy<br>Patients on this protocol will still get treated based on target generated by interventional cerebral arteriography but also receive CT angiography. | Other: CT angiography<br>* CT angiography uses a CT scanner to produce detailed images of both blood vessels and tissues in various parts of the body. An iodine-rich contrast material (dye) is usually injected through a small catheter placed in a vein of the arm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate whether target(s) based on CT angiogram can accurately and precisely identify the target nidus as well as an interventional cerebral arteriography. | The target volume generated by CT angiogram will be compared to the target volume generated by interventional cerebral arteriography superimposed to MRI of brain. Target is defined as the AVM nidus excluding the feeding artery and draining vein or hemangioma, if present. | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To analyze and compare dosimetric parameters: planning target volume | Analyze and compare dosimetric parameters: Planning target volume (PTV) of an SRS treatment plan based on CT angiograms with PTV base on interventional cerebral arteriography superimposed to MRI of brain. | 1 day | 
| To analyze and compare dosimetric parameters: volume of the brain that receives at least 12 Gray of radiaton (V12) | Analyze and compare dosimetric parameters: volume of the brain that receives at least 12 Gray of radiaton (V12) of an SRS treatment plan based on CT angiograms with V12 base on interventional cerebral arteriography superimposed to MRI of brain. | 1 day | 
| To evaluate the total time it takes to perform the additional CT angiograms and compare it to the duration of the interventional procedure. |  | 1 day |