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The Wada activation test, identified by CPT® Code 95958, is a specialized procedure designed to assess hemispheric function in the brain, particularly in relation to language and memory. This test is crucial for patients who are candidates for surgical interventions, such as those undergoing treatment for epilepsy or other neurological conditions. The primary objective of the Wada test is to ascertain which hemisphere of the brain—right or left—dominates language function and to evaluate the contributions of each hemisphere to memory processes. Typically, the left hemisphere is associated with language control, while both hemispheres play roles in memory, albeit with one side often being more dominant. However, individual variations exist, making this assessment vital for personalized treatment planning. During the procedure, electroencephalographic (EEG) monitoring is employed to observe brain activity. This involves placing electrodes on the patient's scalp, which are connected to a recording device to capture electrical activity in the brain. The physician administers an anesthetic into one of the internal carotid arteries, effectively 'putting to sleep' the corresponding hemisphere of the brain. This allows for a clear evaluation of the awake hemisphere's ability to perform language and memory tasks. The physician tests the patient's speech capabilities and recognition of visual stimuli, such as cards with pictures and words, to determine the functional dominance of the active hemisphere. After the anesthetic effect wears off, the process is repeated for the opposite hemisphere, allowing for a comprehensive comparison of both sides. The findings from the Wada test are documented in a written report, providing essential insights for surgical decision-making and patient management.
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The Wada activation test is indicated for patients who are being evaluated for surgical interventions related to epilepsy or other neurological conditions. The following conditions may warrant the performance of this test:
The Wada activation test involves several critical procedural steps to ensure accurate assessment of hemispheric function. The following outlines the detailed steps of the procedure:
Post-procedure care for the Wada activation test involves monitoring the patient as the effects of the anesthetic wear off. Patients may experience temporary confusion or disorientation as the brain recovers from the anesthetic. It is essential to provide a safe environment for the patient during this recovery phase. The physician will analyze the recorded EEG data and the patient's responses to determine the dominant hemisphere for language and memory. A comprehensive written report of the findings will be generated, which will assist in guiding further treatment decisions and surgical planning.
| Short Descr | EEG MONITORING/FUNCTION TEST | Medium Descr | WADA ACTIVATION TEST HEMISPHERIC FUNCTION W/EEG | Long Descr | Wada activation test for hemispheric function, including electroencephalographic (EEG) monitoring | 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) | 0 - Payment restriction for assistants at surgery applies to this procedure... | 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 | Procedure or Service, Not Discounted when Multiple | Berenson-Eggers TOS (BETOS) | P6C - Minor procedures - other (Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 199 - Electroencephalogram (EEG) |
| 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. | 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). | 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. | GC | This service has been performed in part by a resident under the direction of a teaching physician | LT | Left side (used to identify procedures performed on the left side of the body) |
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| 2011-01-01 | Changed | Medium description changed. |
| Pre-1990 | Added | Code added. |
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