Coverage Policy

The following Coverage Policy applies to health benefit plans administered by Cigna Companies. Certain Cigna Companies and/or lines of business only provide utilization review services to clients and do not make coverage determinations. References to standard benefit plan language and coverage determinations do not apply to those clients.

Coverage Policies are intended to provide guidance in interpreting certain standard benefit plans administered by Cigna Companies. Please note, the terms of a customer’s particular benefit plan document [Group Service Agreement, Evidence of Coverage, Certificate of Coverage, Summary Plan Description (SPD) or similar plan document] may differ significantly from the standard benefit plans upon which these Coverage Policies are based. For example, a customer’s benefit plan document may contain a specific exclusion related to a topic addressed in a Coverage Policy. In the event of a conflict, a customer’s benefit plan document always supersedes the information in the Coverage Policies. In the absence of a controlling federal or state coverage mandate, benefits are ultimately determined by the terms of the applicable benefit plan document.

Coverage determinations in each specific instance require consideration of 1) the terms of the applicable benefit plan document in effect on the date of service; 2) any applicable laws/regulations; 3) any relevant collateral source materials including Coverage Policies and; 4) the specific facts of the particular situation.

Each coverage request should be reviewed on its own merits. Medical directors are expected to exercise clinical judgment where appropriate and have discretion in making individual coverage determinations. Where coverage for care or services does not depend on specific circumstances, reimbursement will only be provided if a requested service(s) is submitted in accordance with the relevant criteria outlined in the applicable Coverage Policy, including covered diagnosis and/or procedure code(s).

Reimbursement is not allowed for services when billed for conditions or diagnoses that are not covered under this Coverage Policy (see “Coding Information” below). When billing, providers must use the most appropriate codes as of the effective date of the submission. Claims submitted Medical Coverage Policy: 0521 for services that are not accompanied by covered code(s) under the applicable Coverage Policy will be denied as not covered.

Coverage Policies relate exclusively to the administration of health benefit plans. Coverage Policies are not recommendations for treatment and should never be used as treatment guidelines. In certain markets, delegated vendor guidelines may be used to support medical necessity and other coverage determinations.

This Coverage Policy addresses:

• Ambulatory electroencephalography (EEG) for the diagnosis and management of seizure activity,
• Digital EEG spike analysis.

Coverage Policy

Ambulatory Electroencephalography

Ambulatory electroencephalography (EEG) following completion of a routine EEG is considered medically necessary for the diagnosis and management of seizure activity when ANY of the following criteria is met:

• exclusion of non-neurological causes of seizure-like activity
• inconclusive routine EEG
• suspected epilepsy when the history, clinical examination, and routine EEG is inconclusive
• suspected seizures of sleep disturbances
• individual with confirmed epilepsy who is experiencing suspected non-epileptic events
• classification of seizure type for the selection or adjustment of anti-epileptic medication
• seizures which are precipitated by naturally occurring cyclic events or environmental stimuli which are not reproducible in the hospital or clinic setting

Ambulatory EEG is not covered or reimbursable for the diagnosis and management of ANY other indication.

Digital EEG Spike Analysis

Digital EEG spike analysis (CPT® code 95957) performed in conjunction with an EEG is considered medically necessary for topographic voltage and dipole analysis in presurgical candidates with intractable (e.g., medically refractory, drug-resistant) epilepsy.

Digital EEG spike analysis (CPT® code 95957) performed in conjunction with an EEG is not covered or reimbursable for ANY other indication. Digital EEG spike analysis performed in conjunction with a routine EEG is not covered or reimbursable for ANY indication.

General Background

A seizure is a burst of uncontrolled electrical activity in the brain that causes temporary abnormalities in movements, muscle tone, behaviors, sensations, and/or states of awareness. Epilepsy is a chronic seizure disorder, characterized by recurring, unprovoked seizures. Epilepsy is diagnosed when an individual has one of the following: at least two unprovoked (or reflex) seizures which occur more than 24 hours apart; one unprovoked (or reflex) seizure with a probability of further seizures occurring over the next ten years; or a diagnosis of an epilepsy syndrome (Schachter, 2021). Approximately one in 26 people will develop epilepsy. Seizures and epilepsy are more common in young children and older adults, and men are affected more often than women.

Epilepsy is more prevalent in individuals of Hispanic background vs. non-Hispanics. The number of people who develop epilepsy over a lifetime (i.e., lifetime prevalence) is higher in Black individuals than in white individuals, while poorly controlled or uncontrolled epilepsy is more common in white individuals. These differences may be related to social and economic factors (e.g., socioeconomic status; location and quality of health care) (Epilepsy Foundation, 2014).

Epileptic seizures can last for several minutes and, depending on the region of the brain affected, can bring about fainting, involuntary and violent shaking, or brief episodes of unconsciousness. Epilepsy may result from: structural abnormalities in the brain; genetic variants (e.g., SCN1A gene mutations in Dravet syndrome); infection (e.g., cerebral malaria); metabolic disorders; or immune disorders. In some cases the underlying cause may be unknown (Scheffer, et al., 2017).

Seizure type and precipitating causes are evaluated to determine the best course of treatment. A seizure does not necessarily mean that a person has epilepsy. There are numerous conditions that can be associated with convulsive events that can resemble seizures/epilepsy, and these should be carefully excluded (Epilepsy Foundation, 2022). The diagnosis of epilepsy can be complicated, and it is not unusual to have a misdiagnosis.

Diagnosing Epileptic Seizures

Diagnosing epileptic seizures is made by analyzing the patient’s clinical history, laboratory results, and an electroencephalogram (EEG). An EEG is an important diagnostic test in assessing a patient with potential epilepsy. It can support the diagnosis of epilepsy and also assist in classifying the underlying epileptic syndrome. An EEG measures the electrical activity of the brain (i.e., brainwaves) using recording equipment attached to the scalp by electrodes. The EEG is used in the evaluation of brain disorders, and most commonly used to show the type and location of the activity in the brain during a seizure. It may also be used to evaluate problems associated with brain function such as confusion and long-term difficulties with thinking or memory.

An EEG is obtained to document the presence and frequency of the abnormal neuron activity. In most cases a routine EEG can identify brain activity specific to seizures. The EEG can provide support for the diagnosis of epilepsy and also assist in classifying the underlying epileptic syndrome. However, there are several reasons a routine EEG alone cannot be used to make or refute a specific diagnosis of epilepsy in some cases (Moeller, et al., 2020):

• Most EEG patterns can be caused by a wide variety of neurologic diseases.
• Many diseases can cause more than one type of EEG pattern.
• Intermittent EEG changes, including interictal epileptiform discharges, can be infrequent and may not appear during the relatively brief period of routine EEG recording.
• The EEG can be abnormal in some persons with no other evidence of disease.
• Not all cases of brain disease are associated with an EEG abnormality, particularly if the pathology is small, chronic, or located deep in the brain.
• For some individuals diagnosed with epilepsy, the EEG may remain normal.
• Spike discharges may not be captured on an EEG because their occurrence is rare, or their site of origin is very small or within an occult area of the cortex.
• Spike activity can also be affected by antiepileptic medication.
• A normal patient may show unusual brain activity on an EEG and be incorrectly diagnosed.

When a definitive diagnosis cannot be made from a clinical examination and a resting EEG, additional testing may be necessary (e.g., ambulatory EEG, video EEG).

A prolonged ambulatory EEG in the Medical Coverage Policy: 0521 outpatient/home setting may be used to differentiate between the presence of epileptic, non-epileptic or psychogenic seizure disorders (Abou-Khalil, et al., 2022).

Ambulatory Electroencephalography (EEG)

Ambulatory EEG monitoring is performed by a recorder for up to 96 hours and continuously records brain wave patterns during a patient's routine daily activities and sleep. An ambulatory EEG can be done with or without video recording. The monitoring equipment includes an electrode set, preamplifiers, and a recorder. The electrodes attach to the scalp, and the leads are connected to a recorder, usually worn on a belt.

Ambulatory EEG allows patients to be evaluated in their natural environments, with exposure to potential stressors and other seizure triggers. Prolonged continuous ambulatory EEG recording throughout one or more complete natural sleep/wake cycles increases the likelihood of documenting an ictal (seizure) episode. The most helpful finding on EEG is interictal epileptiform discharges (IEDs), which are spikes, polyspikes, sharp waves, or spike and slow-wave complexes without observed clinical seizures. An IED pattern is believed to be associated with a relatively high risk for having seizures. For 95% of epilepsy patients, IEDs are identified within 48 hours of recording (Tatum, et al., 2018; Seneviratne, et al., 2013; Faulkner, et al., 2012).

Routine EEG has low sensitivity in epilepsy ranging from 25%–55%, with a variable specificity, especially in children (Moeller, et al., 2020). Serial routine EEGs, studies performed a short time after an epileptic seizure, as well as sleep-deprived EEG studies increase the overall diagnostic yield. However, those methods are usually considered inferior to long-term EEG monitoring, where the duration of recording is measured in hours or days (Keezer, et al., 2016).

Ambulatory EEG recordings can be utilized in the evaluation and differential diagnosis of non-epileptic seizures if these episodes are unable to be diagnosed by conventional studies. There are two categories of non-epileptic seizures: pathophysiological events and non-epileptic psychopathological/psychiatric events. Pathophysiological events include autonomic disorders, cardiac arrhythmias, drug toxicity, metabolic disorders, migraines, orthostatic hypotension, sleep disorders, valvular heart disease, vasovagal syncope, and vestibular disorders. Non-epileptic psychopathological/psychiatric events include anxiety, depression, panic attacks, psychogenic seizures, and psychosis (Mesraoua, et al., 2012).

Syncope, for example, shares some clinical characteristics with seizures and may lead to diagnostic confusion. Seizures and syncope may also coexist in a given individual. In general, a syncopal episode or temporary loss of consciousness may be considered unrelated to epilepsy if any of the following features are present:

• prodromal symptoms that on other occasions have been abolished by sitting or lying down
• prolonged standing that appeared to precipitate the temporary loss of consciousness
• pallor during the episode
• sweating before the episode

Sleep and sleep stage have a significant impact on the incidence and frequency of both seizures and epileptiform discharges that occur in between seizures. Generally, non-rapid eye movement (NREM) sleep facilitates IEDs and seizures, while rapid eye movement (REM) sleep tends to inhibit seizures. Prolonged outpatient ambulatory, inpatient video-EEG recordings, or overnight video-EEG polysomnography are of higher yield in detecting IEDs and capturing seizures in the sleep-related focal epilepsies (St. Louis and Foldvary-Schaefer, 2020).

U.S. Food and Drug Administration (FDA): The FDA has approved several wearable EEG devices for use in the ambulatory setting as Class II 510(k) medical devices, including the TrackIt T4 (Lifelines LTD, Over Wallop, GB) and the Apollo (Cadwell Industries, Inc., Kennewick, WA).

Medical Coverage Policy: 0521 Devices may vary in number of channels recorded and recording time, and some newer iterations include wireless data transmission and/or video recording integration.

Literature Review:

The published peer-reviewed medical literature contains some evidence primarily in the form of case series to support the use of ambulatory EEG. While the supporting evidence is not robust, the use of ambulatory EEG monitoring has become a standard of care within the set of diagnostic evaluations of epilepsy versus a non-epileptic syndrome for a subset of individuals. Prospective and retrospective studies have reported the value of adding ambulatory EEG to standard EEG recording data in confirming the presence or absence of epileptic conditions.

Carlson et al. (2018) published the results of a prospective study that evaluated the diagnostic efficacy and technical quality of home video telemetry (HVT) in comparison with inpatient video telemetry (IVT) in a pediatric group. Included patients (n=62) were age 18 years and younger with video telemetry of 24–72 hours. Thirty–three patients were in the HVT group with 29 in the IVT group.

The aim of the study was to determine if the performance of HVT was comparable to that of IVT in a pediatric group in terms of diagnostic efficacy, recording quality and acceptability to parents or caregivers. The diagnostic accuracy between the two groups was comparable with 64% of HVT patients and 62% of IVT patients having typical attacks during the recording. Equipment difficulties occurred in 52% of HVT studies which included camera positioning and failure to turn on the infrared button at night and resulted in a loss of diagnostic information in 15% of patients. Author reported limitations of the study included the lack of randomization and the subjective nature of recording quality assessment by a variety of clinical physiologists. The authors concluded that in a pediatric setting HVT is able to provide similar technical and diagnostic quality results when compared to IVT.

In a prospective study (n=72) by Keezer et al. (2016), the sensitivity of ambulatory EEG was reported to be 2.23 times greater than that of routine EEG (p<0.0001). Ambulatory EEG results have been reported to change clinical management in up to 51% of patients, with a median recording duration of 1.4 days (Faulkner, et al., 2012). Prolonged ambulatory EEG has been found to have a higher probability of recording an epileptic event relative to sleep-deprived EEG (15.2% versus 0%, respectively; p=0.01) (Liporace, et al., 1998).

Digital EEG Spike Analysis

Patients who have epilepsy and do not successfully respond to antiseizure drug therapy are considered to have drug-resistant epilepsy (DRE). This condition is also known as intractable, medically refractory, or pharmacoresistant epilepsy. Refractory epilepsy is defined by failure of two antiepileptic drugs, and the patient may be referred to an epilepsy center for diagnosis and consideration of the many therapeutic options currently available.

In addition to a careful history and physical examination directed at determining seizure type, site of origin, and etiology, the most important diagnostic test for evaluating intractable seizures is prolonged simultaneous video and EEG monitoring. Video EEG may need to continue for days or weeks to obtain enough spells to make a correct diagnosis. Surgery for resection of the epilepsy focus is currently the only available method of curing epilepsy (About-Khalil, et al., 2022; Padin-Rosado, 2021).

Prolonged monitoring for epilepsy surgery is often divided into two phases. Testing in the first phase is noninvasive and sets out to determine the type of epilepsy and whether or not the epilepsy is pharmacotherapy-resistant. Phase two consists of semi-invasive and invasive techniques to locate the areas of the brain from which the seizures originate (Mesraoua, et al., 2012). As such, ambulatory and video EEG may be appropriate during phase one, while more advanced EEG testing is needed in phase two.

Currently, EEGs are primarily performed on digital machines instead of older analog machines. Automated spike and seizure detectors are usually built into digital routine EEG, ambulatory EEG,Medical Coverage Policy: 0521 or video-EEG monitoring. Because of this enhancement, substantial additional analysis by the physician and/or technician is typically not necessary. The most intense use of EEG source localization is in epilepsy, with the intention to localize the epileptic zone in pharmacoresistant focal epilepsies.

The added value of this method in the pre-surgical assessment of these patients has been demonstrated repeatedly, not only for focus localization, but also for localization of those areas necessary for language, motor, and sensory functions (i.e., “eloquent cortex”), which cannot be resected without causing unacceptable neurologic deficits (Abou-Khalil, et al., 2022; Michel and Brunet, 2019). Most practitioners would not have the opportunity to do this advanced analysis, which would be more commonly used at specialty centers (e.g., epilepsy surgery programs) (American Clinical Neurophysiology Society [ACNS], 2008).

Professional Societies/Organizations

American Clinical Neurophysiology Society (ACNS)

According to the ACNS, indications for long term EEG monitoring (e.g., ambulatory EEG) include the following:

1. Identification of epileptic paroxysmal electrographic and/or behavioral abnormalities. These include epileptic seizures (overt and subclinical), and documentation of interictal epileptiform discharges.
2. Verification of the epileptic nature of the new “spells” in a patient with previously documented and controlled seizures.
3. Classification of clinical seizure type(s) in a patient with documented but poorly characterized epilepsy.

The ACNS has further stated that EEG and/or behavioral abnormalities may assist in the differential diagnosis between epileptic disorders and conditions associated with intermittent symptoms due to non-epileptic mechanisms (e.g., syncope, narcolepsy, other sleep disturbances, psychogenic seizures) (ACNS, 2008).

The American Academy of Neurology (AAN) (2013):

The AAN published a recommendation that EEG not be performed for headaches as it offers no advantage over clinical evaluation in diagnosing headache, nor does it improve outcomes.