A Comparison of Methods for Assisting Needle Angle Selection During Image-guided Tissue Biopsy

Background:

• Currently, standard/conventional CT-guided biopsies proceed as follows the physician:

• obtains a pre-procedural CT scan,
• plans the needle s angle based on this CT scan,
• selects the angle at which the needle should be inserted based on the pre-procedural CT scan,
• inserts the needle while aiming to replicate that planned needle angle by using only their visual-spatial abilities, and
• re-images the patient to confirm needle location followed by needle

repositioning, if needed.

• Improving upon these standard methods of needle placement could have

widespread benefits (e.g. improved diagnostic tissue sampling, decreased

needle repositionings, etc.) We will be studying three needle angle selection systems. The laser-assisted needle angle selection system or LNASS, is a custom fabricated device that uses a Class II pointer similar to ones used for pointing at slides during lectures.

Objectives:

• To compare the angle difference between L-NASS (Method A) and the standard method (clinician intuition/conventional method)
• To compare the angle difference between B-NASS (Method B) and the standard method (clinician intuition)
• To compare the angle difference between the mobile device-NASS or MD-NASS (C) and the standard method (clinician intuition/conventional method)

Eligibility:

• Ages Eligible for Study: 18 Years and older
• Genders Eligible for Study: Both
• Inclusion:

• Must be undergoing a scheduled CT-guided biopsy.
• Must have ability to follow breathing instructions like holding breath (if procedure is to be performed without general anesthesia).
• Exclusion:
• No serious concurrent medical illness that would preclude the patient from making a rational informed decision on participation.
• Any known allergy to plastics or polymers (since the Ultem polymer could theoretically induce a rash in these patients, even though it is hypoallergenic).
• Pacemakers or automatic implantable cardiac defibrillators.
• Gross body weight above the CT table limit (450 pounds).

Design:

• Primary outcome measure for the first arm is:

--The difference between planned and achieved needle angle of a laser-assisted needle angle selection system with the standard method (clinician s intuition or conventional method) of CT-guided biopsy.

• Primary outcome measure for the second arm is:

--The difference between planned and achieved needle angle of a block with pre-drilled needle angles with the standard method (clinician s intuition or conventional method) of CT-guided biopsy

• Primary outcome for the third arm is:

--The difference between planned and achieved needle angle of a mobile device-assisted needle angle selection system with the standard method (clinician's intuition or conventional method) of CT-guided biopsy.

• The tool for measuring the needle angles will be an FDA-approved electromagnetic tracking system, which tracks needle movement and position.
• These comparisons will be done as a bystander study.
• Needle guidance system will only be used initially to select the angle during a superficial, shallow needle insertion at the skin surface (less than 1 cm deep).
• At no time will the needle enter tissue that it wouldn t have otherwise entered as none of the system will be used to perform the biopsies at this time.
• The key portions of the procedure will not be altered in any substantive way.

• INCLUSION CRITERIA:

Patients must fulfill all of the following criteria to be eligible for study admission:

• All patients must be undergoing a CT-guided biopsy.
• Age greater than 18 years.
• No serious concurrent medical illness that would preclude the patient from making a rational informed decision on participation.
• The ability to understand and willingness to sign a written informed consent form, and to comply with the protocol. If in question, an ethics consult will be obtained.
• Ability to follow breathing instructions like holding breath (if procedure is to be performed without general anesthesia).
• Patients must be actively enrolled on an NIH protocol and be scheduled for a CT-guided biopsy.

Exclusion criteria

• Patients with an altered mental status that precludes understanding or consenting for the biopsy procedure will be excluded from this study.
• Patients unlikely to be able to hold reasonably still on a procedure table for the length of the procedure.
• Patients with any known allergy to plastics or polymers (since the Ultem -polymer could theoretically induce a rash in these patients, even though it is hypoallergenic).
• Inability to follow breathing instructions, if without general anesthesia.
• Patients with pacemakers or automatic implantable cardiac defibrillators.
• Gross body weight above the CT table limit (450 pounds).