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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. It is commonly performed to diagnose seizure disorders, assess the cause of confusion, investigate episodes of unconsciousness, evaluate head injuries, and detect other brain-related issues such as tumors, infections, degenerative diseases, or metabolic disturbances. Additionally, an EEG can be utilized to evaluate sleep disorders. During the procedure, a trained EEG technician applies sixteen or more electrodes to specific locations on the scalp using a conductive sticky paste. These electrodes are connected to an amplifier and a recording machine, which captures the brain's electrical signals. The patient is instructed to lie still with their eyes closed while the machine is activated, initiating the recording process. The electrical signals from the brain are transformed into wavy lines, which are documented on a moving piece of graph paper. To enhance the test's effectiveness, the patient may be asked to hyperventilate or undergo photic stimulation during the awake phase to potentially trigger seizure activity. For certain types of abnormal brain electrical activity, it is necessary for the patient to be drowsy or asleep, which may require the patient to have a reduced amount of sleep the night before the EEG. The physician subsequently reviews the recorded data and provides a comprehensive written interpretation of the results. It is important to note that different CPT codes are used for various EEG recording scenarios: CPT® Code 95816 is designated for EEG recordings with the patient awake and drowsy, CPT® Code 95819 is for recordings with the patient awake and asleep, and CPT® Code 95822 is for EEG recordings conducted on a patient who is in a coma or asleep.
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The electroencephalogram (EEG) is indicated for several clinical scenarios, particularly when there is a need to assess brain activity and diagnose neurological conditions. The following are the primary indications for performing an EEG:
The procedure for conducting an electroencephalogram (EEG) involves several key steps to ensure accurate recording of brain activity. The following outlines the procedural steps:
Post-procedure care following an electroencephalogram (EEG) typically involves minimal requirements, as the procedure is non-invasive and does not usually necessitate extensive recovery time. Patients may resume their normal activities immediately after the test. However, it is advisable for patients to follow any specific instructions provided by the physician, particularly if any medications were adjusted prior to the procedure. The physician will review the recorded EEG data and communicate the findings to the patient, which may include recommendations for further evaluation or treatment based on the results. In some cases, follow-up appointments may be scheduled to discuss the interpretation of the EEG and any necessary next steps in the patient's care plan.
| Short Descr | EEG AWAKE AND ASLEEP | Medium Descr | ELECTROENCEPHALOGRAM W/REC AWAKE&ASLEEP | Long Descr | Electroencephalogram (EEG); including recording awake and asleep | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | CR | Catastrophe/disaster related | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | KX | Requirements specified in the medical policy have been met | 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 | 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). | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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. | 27 | Multiple outpatient hospital e/m encounters on the same date: for hospital outpatient reporting purposes, utilization of hospital resources related to separate and distinct e/m encounters performed in multiple outpatient hospital settings on the same date may be reported by adding modifier 27 to each appropriate level outpatient and/or emergency department e/m code(s). this modifier provides a means of reporting circumstances involving evaluation and management services provided by physician(s) in more than one (multiple) outpatient hospital setting(s) (eg, hospital emergency department, clinic). note: this modifier is not to be used for physician reporting of multiple e/m services performed by the same physician on the same date. for physician reporting of all outpatient evaluation and management services provided by the same physician on the same date and performed in multiple outpatient setting(s) (eg, hospital emergency department, clinic), see evaluation and management, emergency department, or preventive medicine services codes. | 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). | 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). | 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. | 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. | 79 | Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.) | 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. | A1 | Dressing for one wound | AF | Specialty physician | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | 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 | GA | Waiver of liability statement issued as required by payer policy, individual case | GB | Claim being re-submitted for payment because it is no longer covered under a global payment demonstration | GP | Services delivered under an outpatient physical therapy plan of care | 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 | 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 | 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 | 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 | 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) | UD | Medicaid level of care 13, as defined by each state | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner |
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| 2011-01-01 | Changed | Short description changed. |
| 2003-01-01 | Changed | Code description changed. |
| Pre-1990 | Added | Code added. |
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