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Visual evoked potential (VEP) testing, also known as visually evoked response (VER) and visually evoked cortical potential (VECP), is a diagnostic procedure utilized to assess the functionality of the visual pathways within the central nervous system, excluding conditions related to glaucoma. The visual pathways begin at the retina, extend through the optic nerves, and culminate in the visual cortex of the brain. This testing method employs scalp electrodes to capture the electrical potentials generated in response to brief visual stimuli. During the procedure, the planned electrode sites on the scalp are meticulously cleansed to ensure optimal conductivity, and both recording and grounding electrodes are strategically positioned. The visual stimuli can be delivered in two primary forms: a flash of light or a checkerboard pattern. The flash stimulus involves a strobe light that rapidly alternates on and off, while the checkerboard stimulus consists of a black and white pattern that reverses colors at half-second intervals. As the patient concentrates on the checkerboard, the VEP waveforms are recorded, allowing for the extraction of data from an electroencephalogram through signal averaging techniques. The resulting waveforms are displayed on a computer screen and can also be printed for further analysis. Following the test, the physician meticulously reviews the recorded waveforms and generates a comprehensive written interpretation and report detailing the findings of the VEP test.
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The visual evoked potential (VEP) testing is indicated for various conditions and symptoms that may affect the visual pathways. The following are the explicitly provided indications for performing this procedure:
The procedure for visual evoked potential (VEP) testing involves several critical steps to ensure accurate results. The following outlines the procedural steps as described:
After the visual evoked potential (VEP) testing is completed, there are typically no specific post-procedure care requirements, as the test is non-invasive and does not involve any recovery time. Patients can resume their normal activities immediately following the procedure. The physician will provide the patient with the results of the test during a follow-up appointment, where the interpretation and implications of the findings will be discussed. It is important for patients to understand the significance of the results and any further evaluations or treatments that may be recommended based on the VEP findings.
| Short Descr | VISUAL EP TEST CNS W/I&R | Medium Descr | VISUAL EP TESTING CNS EXCEPT GLAUCOMA W/I&R | Long Descr | Visual evoked potential (VEP) checkerboard or flash testing, central nervous system except glaucoma, with interpretation and report | 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) | 2 - 150% payment adjustment 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 | Type of Service (TOS) | Q - Vision Items or Services | Berenson-Eggers TOS (BETOS) | T2D - Other tests - other | MUE | 1 | CCS Clinical Classification | 7 - Other diagnostic nervous system procedures |
This is a primary code that can be used with these additional add-on codes.
| 95940 | Addon Code Resequenced Code MPFS Status: Active Code APC N Continuous intraoperative neurophysiology monitoring in the operating room, one on one monitoring requiring personal attendance, each 15 minutes (List separately in addition to code for primary procedure) | 95941 | Addon Code Resequenced Code MPFS Status: Not valid for Medicare purposes APC N Continuous intraoperative neurophysiology monitoring, from outside the operating room (remote or nearby) or for monitoring of more than one case while in the operating room, per hour (List separately in addition to code for primary procedure) | G0453 | Add-on Code Medicare Coverage: Carrier Priced MPFS Status: Active Code APC N Continuous intraoperative neurophysiology monitoring, from outside the operating room (remote or nearby), per patient, (attention directed exclusively to one patient) each 15 minutes (list in addition to primary procedure) |
| 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. | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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 | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | GW | Service not related to the hospice patient's terminal condition | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CR | Catastrophe/disaster related | FP | Service provided as part of family planning program | GC | This service has been performed in part by a resident under the direction of a teaching physician | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | GZ | Item or service expected to be denied as not reasonable and necessary | LT | Left side (used to identify procedures performed on the left side of the body) | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | RT | Right side (used to identify procedures performed on the right side of the body) |
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| 2018-01-01 | Changed | Long medium and short descriptions changed. |
| 1996-01-01 | Added | First appearance in code book in 1996. |
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