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Official Description

Electroencephalogram (EEG) extended monitoring; 61-119 minutes

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

An electroencephalogram (EEG) with extended monitoring, specifically coded as CPT® 95813, refers to a diagnostic procedure that records the electrical activity of the brain for a duration of 61 to 119 minutes. This extended monitoring is crucial for obtaining a comprehensive assessment of brain function, particularly in cases where shorter monitoring periods may not provide sufficient data. The EEG is instrumental in diagnosing various neurological conditions, including seizure disorders, confusion, unconsciousness, head injuries, and other brain-affecting conditions such as tumors, infections, degenerative diseases, or metabolic disturbances. Additionally, EEGs can be utilized to evaluate sleep disorders, providing insights into the brain's activity during different sleep stages. During the procedure, a trained EEG technician applies 16 or more electrodes to the patient's scalp, using a conductive paste to ensure optimal signal transmission. These electrodes are connected to an amplifier and recording device, which captures the brain's electrical signals. The patient is instructed to remain still with their eyes closed to minimize artifacts in the recording. Once the machine is activated, it begins to convert the brain's electrical signals into graphical representations, typically displayed as wavy lines on graph paper. Throughout the recording, specific techniques such as hyperventilation or photic stimulation may be employed to provoke seizure activity, aiding in the diagnostic process. After the monitoring period, a physician reviews the recorded data and provides a detailed written interpretation of the findings, which is essential for guiding further clinical decisions.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The electroencephalogram (EEG) extended monitoring, coded as CPT® 95813, is indicated for several clinical scenarios where detailed assessment of brain activity is necessary. The following conditions may warrant the use of this procedure:

  • Seizure Disorders - To diagnose and evaluate the presence and type of seizure activity.
  • Confusion - To determine the underlying cause of episodes of confusion in patients.
  • Unconsciousness - To investigate the reasons behind periods of unconsciousness.
  • Head Injury - To assess brain function following a traumatic head injury.
  • Brain Conditions - To identify other conditions affecting the brain, such as tumors, infections, degenerative diseases, or metabolic disturbances.
  • Sleep Disorders - To evaluate and diagnose various sleep-related issues.

2. Procedure

The procedure for conducting an electroencephalogram (EEG) with extended monitoring involves several key steps to ensure accurate recording of brain activity. The following outlines the procedural steps:

  • Preparation of the Patient - The patient is prepared for the EEG by ensuring they are comfortable and informed about the procedure. They are advised to avoid caffeine and certain medications that may affect brain activity prior to the test.
  • Electrode Application - A trained EEG technician applies 16 or more electrodes to the patient's scalp. These electrodes are strategically placed in specific positions using a sticky conductive paste to enhance signal quality.
  • Connection to Recording Equipment - The electrodes are connected via wires to an amplifier and a recording machine. This setup is crucial for capturing the electrical signals generated by the brain.
  • Activation of the Recording Machine - Once the electrodes are in place, the patient is instructed to lie still with their eyes closed. The technician activates the recording machine, which begins to monitor and record the brain's electrical activity.
  • Monitoring Period - The EEG recording lasts for 61 to 119 minutes. During this time, the machine converts the electrical signals from the brain into wavy lines that are recorded on a moving piece of graph paper. The patient may be asked to perform specific tasks, such as hyperventilating or responding to photic stimulation, to provoke potential seizure activity.
  • Completion of the Procedure - After the designated monitoring period, the recording is stopped, and the electrodes are carefully removed from the patient's scalp. The technician ensures that the patient is comfortable and provides any necessary post-procedure instructions.

3. Post-Procedure

After the electroencephalogram (EEG) extended monitoring is completed, the patient may resume normal activities unless otherwise instructed by the physician. There are typically no significant recovery requirements, as the procedure is non-invasive and does not involve sedation. The physician will review the recorded data and provide a written interpretation of the results, which may take some time to process. Patients may be advised to follow up with their healthcare provider to discuss the findings and any further diagnostic or treatment options based on the EEG results.

Short Descr EEG EXTND MNTR 61-119 MIN
Medium Descr EEG EXTENDED MONITORING 61-119 MINUTES
Long Descr Electroencephalogram (EEG) extended monitoring; 61-119 minutes
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.
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
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.
GW Service not related to the hospice patient's terminal condition
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
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.
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).
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.
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.
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
CR Catastrophe/disaster related
ET Emergency services
GT Via interactive audio and video telecommunication systems
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
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)
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
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
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
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2020-01-01 Changed Code description changed.
2013-01-01 Changed Medium Descriptor changed.
2011-01-01 Changed Short description changed.
2009-01-01 Changed Code description changed
1995-01-01 Added First appearance in code book in 1995.
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