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Official Description

Magnetic resonance imaging guidance for needle placement (eg, for biopsy, needle aspiration, injection, or placement of localization device) radiological supervision and interpretation

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

This CPT® code 77021 pertains to the use of magnetic resonance imaging (MRI) guidance specifically for the placement of needles in various medical procedures, including biopsies, needle aspirations, injections, or the placement of localization devices. The procedure involves the utilization of MRI technology to accurately locate the target area within the body that requires intervention. Once the area is identified, it is typically anesthetized to minimize discomfort during the procedure. Following this, a needle is inserted under the guidance of MRI to carry out the intended action, which may involve extracting tissue samples for biopsy, administering therapeutic or diagnostic injections, or positioning a localization device for further examination of a tumor or mass. MRI is a sophisticated imaging modality that is non-invasive and does not involve ionizing radiation, making it a safer alternative for patients. It operates on the principle of magnetic properties of hydrogen atoms present in the body. When exposed to a strong magnetic field and radiofrequency waves, these hydrogen nuclei emit signals that are captured and processed by a computer to generate high-resolution, three-dimensional images of the internal structures. This imaging capability is crucial for ensuring precise needle placement, which is essential for the success of the procedures being performed. Additionally, the needles used in conjunction with MRI guidance may be specially designed with features such as metallic ringlets, contrast material coatings, or signal-receiving coils at their tips to enhance the accuracy and effectiveness of the procedure.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The following indications are explicitly associated with the use of CPT® code 77021 for MRI-guided needle placement:

  • Biopsy - The procedure is indicated for obtaining tissue samples from suspicious lesions or masses to diagnose conditions such as cancer.
  • Needle Aspiration - This procedure is performed to remove fluid or tissue from a specific area for diagnostic analysis or therapeutic purposes.
  • Injection - MRI guidance is utilized for the precise delivery of therapeutic or diagnostic substances into targeted areas, such as joints or tumors.
  • Placement of Localization Device - The procedure may involve placing devices that help in the identification and targeting of lesions for future interventions.

2. Procedure

The procedural steps for MRI-guided needle placement as described in the provided data are as follows:

  • Step 1: Localization of Target Area - The first step involves using MRI technology to accurately identify the target area within the body that requires intervention. This is achieved by obtaining high-resolution images that reveal the anatomical structures and any abnormalities present.
  • Step 2: Anesthesia Administration - Once the target area is localized, local anesthesia is typically administered to the patient to minimize discomfort during the needle placement procedure. This step is crucial for patient comfort and cooperation.
  • Step 3: Needle Insertion - Under continuous MRI guidance, the appropriate type of needle is carefully inserted into the target area. The MRI images provide real-time feedback, allowing the physician to adjust the needle's position as necessary to ensure accurate placement.
  • Step 4: Performing the Procedure - After the needle is correctly positioned, the specified procedure is performed, which may include obtaining tissue samples for biopsy, aspirating fluid, injecting substances, or placing localization devices. The MRI guidance ensures that the procedure is conducted with precision.

3. Post-Procedure

Post-procedure care following MRI-guided needle placement typically involves monitoring the patient for any immediate complications or adverse reactions. Patients may be advised to rest and avoid strenuous activities for a specified period. Follow-up imaging or assessments may be scheduled to evaluate the outcomes of the procedure and ensure that the target area has been adequately addressed. Additionally, patients should be informed about signs of infection or other complications that may require prompt medical attention.

Short Descr MRI GUIDANCE NDL PLMT RS&I
Medium Descr MRI GUIDANCE NEEDLE PLACEMENT RS&I
Long Descr Magnetic resonance imaging guidance for needle placement (eg, for biopsy, needle aspiration, injection, or placement of localization device) radiological supervision and interpretation
Status Code Active Code
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 1 - Diagnostic Tests for Radiology Services
Multiple Procedures (51) 0 - No payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Items and Services Packaged into APC Rates
ASC Payment Indicator Packaged service/item; no separate payment made.
Type of Service (TOS) 4 - Diagnostic Radiology
Berenson-Eggers TOS (BETOS) I2D - Advanced imaging - MRI/MRA: other
MUE 1
CCS Clinical Classification 198 - Magnetic resonance imaging
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
GC This service has been performed in part by a resident under the direction of a teaching physician
TC Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles
LT Left side (used to identify procedures performed on the left side of the body)
RT Right side (used to identify procedures performed on the right side of the body)
X5 Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician
52 Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
MG The order for this service does not have applicable appropriate use criteria in the qualified clinical decision support mechanism consulted by the ordering professional
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
QQ Ordering professional consulted a qualified clinical decision support mechanism for this service and the related data was provided to the furnishing professional
SG Ambulatory surgical center (asc) facility service
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
Date
Action
Notes
2021-01-01 Note Guidelines changed.
2019-01-01 Changed Description Changed
2013-01-01 Changed Guideline information changed.
2011-01-01 Changed Guideline information changed.
2007-01-01 Added First appearance in code book in 2007.
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