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An Electroencephalogram (EEG) is a diagnostic procedure that measures and records the electrical activity of the brain. This test is crucial for identifying various neurological conditions. The EEG is particularly useful in diagnosing seizure disorders, as it can capture abnormal electrical discharges that occur during seizures. Additionally, it helps determine the underlying causes of confusion, investigate episodes of unconsciousness, evaluate head injuries, and identify other brain-related conditions such as tumors, infections, degenerative diseases, or metabolic disturbances. Furthermore, an EEG can be employed to assess sleep disorders, providing insights into the brain's activity during different sleep stages. During the procedure, a trained EEG technician applies sixteen or more electrodes to specific locations on the scalp using a conductive paste, ensuring optimal contact for accurate readings. These electrodes are connected to an amplifier and a recording machine, which translates the brain's electrical signals into wavy lines on graph paper. The patient is instructed to remain still with their eyes closed while the recording takes place. The EEG process includes both awake and drowsy states, with specific techniques such as hyperventilation or photic stimulation used to provoke seizure activity during the awake phase. To capture brain activity during the drowsy or asleep phase, patients are advised to limit their sleep the night before the test. In cases where patients are in a coma, the EEG can still be performed to assess any existing brain activity. After the procedure, a physician reviews the recorded data and provides a comprehensive written interpretation of the results.
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The Electroencephalogram (EEG) is performed for several specific indications, including:
The procedure for conducting an Electroencephalogram (EEG) involves several detailed steps:
Post-procedure care for the patient following an EEG is generally minimal. Patients can typically resume their normal activities immediately after the test. However, they may be advised to avoid any activities that require full concentration, such as driving, until they feel fully alert. The physician will review the recorded EEG data and discuss the findings with the patient during a follow-up appointment, where any necessary further evaluations or treatments will be determined based on the results.
| Short Descr | EEG AWAKE AND DROWSY | Medium Descr | ELECTROENCEPHALOGRAM W/REC AWAKE&DROWSY | Long Descr | Electroencephalogram (EEG); including recording awake and drowsy | 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 | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T2D - Other tests - other | 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. | 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 | 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 | GW | Service not related to the hospice patient's terminal condition | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | GZ | Item or service expected to be denied as not reasonable and necessary | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | Q5 | Service furnished under a reciprocal billing arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | CR | Catastrophe/disaster related | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | 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). | 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 | X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | UD | Medicaid level of care 13, as defined by each state | 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. | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 24 | Unrelated evaluation and management service by the same physician or other qualified health care professional during a postoperative period: the physician or other qualified health care professional may need to indicate that an evaluation and management service was performed during a postoperative period for a reason(s) unrelated to the original procedure. this circumstance may be reported by adding modifier 24 to the appropriate level of e/m service. | 25 | Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service: it may be necessary to indicate that on the day a procedure or service identified by a cpt code was performed, the patient's condition required a significant, separately identifiable e/m service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. a significant, separately identifiable e/m service is defined or substantiated by documentation that satisfies the relevant criteria for the respective e/m service to be reported (see evaluation and management services guidelines for instructions on determining level of e/m service). the e/m service may be prompted by the symptom or condition for which the procedure and/or service was provided. as such, different diagnoses are not required for reporting of the e/m services on the same date. this circumstance may be reported by adding modifier 25 to the appropriate level of e/m service. note: this modifier is not used to report an e/m service that resulted in a decision to perform surgery. see modifier 57 for significant, separately identifiable non-e/m services, see modifier 59. | 53 | Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) 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). | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | AF | Specialty physician | AI | Principal physician of record | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | CG | Policy criteria applied | ET | Emergency services | FS | Split (or shared) evaluation and management visit | G0 | Telehealth services for diagnosis, evaluation, or treatment, of symptoms of an acute stroke | GE | This service has been performed by a resident without the presence of a teaching physician under the primary care exception | KX | Requirements specified in the medical policy have been met | LT | Left side (used to identify procedures performed on the left side of the body) | NB | Nebulizer system, any type, fda-cleared for use with specific drug | 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 | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | RT | Right side (used to identify procedures performed on the right side of the body) | SA | Nurse practitioner rendering service in collaboration with a physician | U6 | Medicaid level of care 6, as defined by each state | X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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Notes
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| 2011-01-01 | Changed | Short description changed. |
| 2003-01-01 | Changed | Code description changed. |
| 1991-01-01 | Added | First appearance in code book in 1991. |
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