CPT® Code 61720

Creation of lesion by stereotactic method, including burr hole(s) and localizing and recording techniques, single or multiple stages; globus pallidus or thalamus

The CPT® Code 61720 refers to the creation of a lesion using a stereotactic method, which involves precise localization and recording techniques, and may be performed in single or multiple stages. This procedure specifically targets the globus pallidus or thalamus, both of which are critical subcortical structures located in the forebrain of the brain. The globus pallidus is characterized as a pale, spherical area that forms part of the lentiform nucleus, which is integral to the basal ganglia. The basal ganglia are large masses of gray matter situated at the base of the cerebral hemispheres and play a significant role in coordinating movement. The thalamus, on the other hand, is a prominent oval structure positioned just above the midbrain and serves as a relay station for sensory and motor signals to the cerebral cortex. Stereotactic lesion creation is categorized as a psychosurgical procedure and is often regarded as investigational or experimental by various payers. The procedure typically begins with the attachment of a specialized frame to the patient's skull, which ensures accurate positioning. Advanced imaging techniques such as MRI or CT scans are utilized to meticulously map the brain and identify the precise locations for lesion creation. The surgical apparatus is then calibrated to align with the MRI or CT coordinates of the targeted area. In some cases, frameless stereotactic surgery may be employed, utilizing fiduciary markers for guidance. To access the subcortical regions, one or more small incisions are made on the lateral aspect of the skull, followed by the creation of burr holes. These burr holes allow for the insertion of electrocautery probes, which are guided to the predetermined lesion site based on the stereotactic coordinates. Once positioned, a radiofrequency current is applied to ablate the targeted tissue. If the desired therapeutic outcome is not achieved during the initial surgical session, the procedure may be repeated in subsequent surgeries. For coding purposes, CPT® Code 61720 is specifically designated for the creation of lesions in the globus pallidus or thalamus, while CPT® Code 61735 is used for lesions in other subcortical structures.