Electroencephalographic (EEG) Video Monitoring

Number: 0322

Table Of Contents

Policy
Applicable CPT / HCPCS / ICD-10 Codes
Background
References

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Policy

Scope of Policy

This Clinical Policy Bulletin addresses electroencephalographic (EEG) video monitoring.

1. Medical Necessity

   1. Aetna considers attended electroencephalographic (EEG) video monitoring performed in a healthcare facility medically necessary for the following indications, where the diagnosis remains uncertain after recent (within the past 90 days) neurological examinations and standard EEG studiesFootnote 1*, and non-neurological causes of symptoms (e.g., syncope, cardiac arrhythmias) have been ruled out:

      1. To differentiate epileptic events from psychogenic seizures; or
      2. To establish the first diagnosis of a seizure disorder; or
      3. To establish the specific type of epilepsy in poorly characterized seizure types where such characterization is medically necessary to select the most appropriate therapeutic regimen; or
      4. To establish the diagnosis of epilepsy and evaluate response to treatment in very young children (3 years of age or younger) and in children with severe cognitive deficits, or older persons who are unable to communicate due to disability; or
      5. To evaluate newborns with proven or suspected acute brain injury and co-morbid encephalopathy.

      Note: Once the cause of seizures and specific type of epilepsy has been established, continued video EEG monitoring (e.g., for monitoring response to therapy or titrating medication dosages in older children and adults) is considered not medically necessary.  In these cases, response to therapy can be assessed using standard EEG monitoring or ambulatory EEG monitoring.

   2. Aetna considers attended EEG video monitoring in a healthcare facility medically necessary for identification and localization of a seizure focus in persons with intractable epilepsy who are being considered for surgery.  See also CPB 0394 - Epilepsy Surgery.

      Aetna considers attended EEG video monitoring for driving clearance not medically necessary treatment of disease.

      Aetna considers attended EEG video monitoring experimental, investigational, or unproven for all other indications (e.g., assessment of obstructive sleep apnea, amyotrophic lateral sclerosis (ALS), cardiac arrest, chronic fatigue, coma, headache, and assessment of the effectiveness of drug treatment in epilepsies, diagnosis of brain death, and prognosis of cardiac arrest treated with hypothermia; not an all inclusive list) because its effectiveness for these indications has not been established.

      Footnote 1* Requirements for a standard EEG and neurologic examination are waived for medically necessary video EEG performed in an intensive care unit (ICU).

   3. Prolonged (greater than 7 days) attended EEG video monitoring in a healthcare facility is considered medically necessary for the following indications:

      1. The member has experienced events so infrequent that there is a significant likelihood that they would not be detected within one week of monitoring; or
      2. An extended stay is necessary for care for an adverse event (eg, postictal psychosis, falls, respiratory failure, status epilepticus); or
      3. The member requires medication adjustments requiring ongoing monitoring (evaluating response) that cannot be safely performed on an outpatient basis.

   Note: The medically necessary level of care a member requires should be addressed individually according to the member's clinical needs.  An acute level of care is not considered medically necessary for many persons requiring video EEG monitoring.

2. Related Policies

   1. CPB 0221 - Quantitative EEG (Brain Mapping)
   2. CPB 0289 - Grid Monitoring and Intraoperative Electroencephalography
   3. CPB 0394 - Epilepsy Surgery
   4. CPB 0425 - Ambulatory Electroencephalography - for home video EEG monitoring, and for video EEG monitoring that is not attended and is performed at a healthcare facility

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Table:

CPT Codes / HCPCS Codes / ICD-10 Codes

Code	Code Description
CPT codes covered if selection criteria are met:
95700	Electroencephalogram (EEG) continuous recording, with video when performed, setup, patient education, and takedown when performed, administered in person by EEG technologist, minimum of 8 channels
95711	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, 2-12 hours unmonitored
95712	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, 2-12 hours with intermittent monitoring and maintenance
95713	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, 2-12 hours with continuous, real-time monitoring and maintenance
95714	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, each increment of 12-26 hours unmonitored
95715	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, each increment of 12-26 hours with intermittent monitoring and maintenance
95716	Electroencephalogram with video (VEEG), review of data, technical description by EEG technologist, each increment of 12-26 hours with continuous, real-time monitoring and maintenance
95718	Electroencephalogram (EEG), continuous recording, physician or other qualified health care professional review of recorded events, analysis of spike and seizure detection, interpretation and report, 2-12 hours of EEG recording with video
95720	Electroencephalogram (EEG), continuous recording, physician or other qualified health care professional review of recorded events, analysis of spike and seizure detection, each increment of greater than 12 hours, up to 26 hours of EEG recording, interpretation and report after each 24-hour period with video
95722	Electroencephalogram (EEG), continuous recording, physician or other qualified health care professional review of recorded events, analysis of spike and seizure detection, interpretation, and summary report, complete study greater than 36 hours, up to 60 hours of EEG recording, with video (VEEG)
95724	Electroencephalogram (EEG), continuous recording, physician or other qualified health care professional review of recorded events, analysis of spike and seizure detection, interpretation, and summary report, complete study greater than 60 hours, up to 84 hours of EEG recording, with video (VEEG)
95726	Electroencephalogram (EEG), continuous recording, physician or other qualified health care professional review of recorded events, analysis of spike and seizure detection, interpretation, and summary report, complete study greater than 84 hours of EEG recording, with video (VEEG)
Other CPT codes related to the CPB:
95705	Electroencephalogram (EEG) without video, review of data, technical description by EEG technologist, 2-12 hours; unmonitored
95706	with intermittent monitoring and maintenance
95707	with continuous, real-time monitoring and maintenance
95812 - 95822	Electroencephalogram (EEG)
99184	Initiation of selective head or total body hypothermia in the critically ill neonate, includes appropriate patient selection by review of clinical, imaging and laboratory data, confirmation of esophageal temperature probe location, evaluation of amplitude EEG, supervision of controlled hypothermia, and assessment of patient tolerance of cooling
ICD-10 codes covered if selection criteria are met:
F44.5	Conversion disorder with seizures or convulsions [psychogenic seizure]
G40.001 - G40.919	Epilepsy and recurrent seizures [EEG video monitoring is not covered for the assessment of the effectiveness of drug treatment in epilepsies]
G40.A01 - G40.B19	Absence and juvenile myoclonic epilepsy
P10.0 - P15.9	Birth trauma [Acute brain injury]
P52	Intracranial nontraumatic hemorrhage of newborn
P90	Convulsions of newborn
P91.811 - P91.819	Neonatal encephalopathy [Co-morbid encephalopathy]
R25.0 - R25.9	Abnormal involuntary movements
R40.4	Transient alteration of awareness
R53.82	Chronic fatigue, unspecified
R56.01	Complex febrile convulsions
R56.1	Post traumatic seizures
R56.9	Unspecified convulsions (e.g., seizure NOS)
R94.01	Abnormal electroencephalogram [EEG]
ICD-10 codes not covered for indications listed in the CPB (not all-inclusive):
G12.21	Amyotrophic lateral sclerosis
G43.001 - G43.E19	Migraine
G44.001 - G44.89	Other headache syndromes
G47.33	Obstructive sleep apnea (adult) (pediatric)
G50.0	Trigeminal neuralgia
G50.1	Atypical facial pain
G93.82	Brain death
I45.0 - I45.9	Other conduction disorders
I46.2 - I46.9	Cardiac arrest
I47.0 - I49.9	Paroxysmal tachycardia, atrial fibrillation and flutter, and other cardiac arrhythmias
R40.20 - R40.244	Coma
R51	Headache
R53.82	Chronic fatigue, unspecified
R55	Syncope and collapse
Z02.4	Encounter for examination for driving license

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Background

The Agency for Health Care Policy and Research has stated that information provided by video electroencephalographic (EEG) monitoring has improved patient outcome by permitting accurate diagnoses and modified therapy.  Furthermore, the American EEG Society has noted that this procedure is widely regarded as safe and effective for evaluating seizures disorders.  The American Epilepsy Society has stated that this technique is the method of choice for the evaluation of intractable and/or undiagnosed seizure disorders.  Additionally, many studies have reported the usefulness of this technique, and recommended its use for the diagnosis of psychogenic seizures.

An evidence report prepared for AHRQ (Ross et al, 2001) concluded that EEG video monitoring was useful for diagnosis of epilepsy if the EEG, CT, and MRI are non-diagnostic, and in diagnosis in very young children, in patients with poorly characterized seizure types, and in those with suspected psychogenic seizures.  The report concluded that video EEG has a role subsequent to a new diagnosis if the diagnosis is or becomes uncertain or if surgery is considered.  "In summary … [t]he literature suggests that ambulatory and video EEGs are useful in a first diagnosis if standard EEG, CT, and MRI are non-diagnostic.  Video EEGs are also useful in diagnosis in very young children, in patients with poorly characterized seizure types, and in those with suspected psychogenic seizures, especially if episodes are frequent."  The report continued: "[T]he evidence, although scant, suggests there is no role for standard EEG in routine monitoring of patients after a new diagnosis of epilepsy.  Video EEG has a role subsequent to a new diagnosis if the diagnosis is or becomes uncertain or if surgery is considered" (Ross et al, 2001).

The role of video and ambulatory EEG is confined to refining or changing an uncertain diagnosis or in preoperative evaluations for seizure surgery (Ross et al, 2001).  When seizures are frequent and features are atypical or uncertain, these EEGs may well contribute information necessary to correct a misdiagnosis.  The literature describing these EEGs appears confined to specialists in academic centers.

An assessment of EEG video monitoring by the Institute for Clinical Effectiveness and Health Policy (Pichon Riviere, et al., 2011) concluded: "In patients with refractory epilepsy who have previously been studied using the standard diagnostic tests, telemetry video electroencephalography (V-EEG) seems to be an adequate diagnostic test to: differentiate a crisis from a pseudocrisis, characterize the different types of crises and localize the epileptic area. Continuous video-EEG monitoring is not considered medically necessary to monitor the antiepileptic drug response or drug titration."

In the intensive care unit (ICU), continuous EEG monitoring for detection of seizures can be performed with or without video monitoring. Clinical studies of CEEG monitoring in the ICU focus primarily on the incidence of seizures encountered in critical care settings, risk factors for seizures in critically ill patients, and the relationship of seizures to clinical outcomes of these patients (see, e.g., Thietler, et al., 2017). There is a lack of reliable evidence of the value of adding a video component to continuous EEG monitoring in the ICU setting. In addition, continuous attended video EEG monitoring is typically performed in an epilepsy monitoring unit. Although continuous EEG monitoring in the ICU or on the hospital floor may include a video component, the video is typically only intermittently attended (Herman, et al., 2015).

Stefan et al (2011) stated that a reliable method for the estimation of seizure frequency and severity is of value in assessing the effectiveness of drug treatment in epilepsies.  These quantities are usually deduced from subjective patient reports, which may cause considerable problems due to insufficient or false descriptions of seizures and their frequency.  In a feasibility study, these researchers presented data from 2 difficult-to-treat patients with intractable epilepsy.  Patient 1 has had an unknown number of complex partial (CP) seizures.  A prolonged outpatient video-EEG monitoring over 160-hr and 137-hr (over an interval of 3 months) was performed with an automated seizure detection method.  Patient 2 suffered exclusively from nocturnal seizures originating from the frontal lobe.  In this case, an objective quantification of the effectiveness of drug treatment over a time period of 22 weeks was established.  For the reliable quantification of seizures, a prolonged outpatient video/video-EEG monitoring was appended after a short-term inpatient monitoring period.  Patient 1: The seizure detection algorithm was capable of detecting 10 out of 11 seizures.  The number of false-positive events was less than 0.03/hr.  It was clearly demonstrated that the patient showed more seizures than originally reported.  Patient 2: The add-on medication of lacosamide led to a significant reduction in seizure frequency and to a marked decrease in the mean duration of seizures.  The severity of seizures was reduced from numerous hyper-motoric seizures to few mild, head-turning seizures.  The authors concluded that outpatient monitoring may be helpful to guide treatment for severe epilepsies and offers the possibility to more reliably quantify the effectiveness of treatment in the long-term, even over several months.  The findings of this feasibility study need to be validated by well-designed studies.

Therapeutic hypothermia (TH) is becoming standard of care in newborns with hypoxic-ischemic encephalopathy (HIE).  The prognostic value of the EEG and the incidence of seizures during TH are uncertain.  Nash and colleagues (2011) described evolution of EEG background and incidence of seizures during TH, and identified EEG patterns predictive for MRI brain injury.  A total of 41 newborns with HIE who underwent TH were included in this study.  Continuous video-EEG was performed during hypothermia and re-warming.  EEG background and seizures were reported in a standardized manner.  Newborns underwent MRI after re-warming.  Sensitivity and specificity of EEG background for moderate-to-severe MRI brain injury was assessed at 6-hr intervals during TH and re-warming.  EEG background improved in 49 %, remained the same in 38 %, and worsened in 13 %.  A normal EEG had a specificity of 100 % upon initiation of monitoring and 93 % at later time points.  Burst suppression and extremely low voltage patterns held the greatest prognostic value only after 24 hrs of monitoring, with a specificity of 81 % at the beginning of cooling and 100 % at later time points.  A discontinuous pattern was not associated with adverse outcome in most patients (73 %).  Electrographic seizures occurred in 34 % (14/41), and 10 % (4/41) developed status epilepticus.  Seizures had a clinical correlate in 57 % (8/14) and were subclinical in 43 % (6/14).  The authors concluded that continuous video-EEG monitoring in newborns with HIE undergoing TH provides prognostic information about early MRI outcome and accurately identifies electrographic seizures, nearly 50 % of which are subclinical.  The findings of this small study need to be validated by well-designed studies.

Rosetti et al (2010) examined if continuous EEG (cEEG) may predict outcome of patients with coma after cardiac arrest (CA), particularly in the setting of TH.  From April 2009 to April 2010, these researchers prospectively studied 34 consecutive comatose patients treated with TH after CA who were monitored with cEEG, initiated during hypothermia and maintained after rewarming.  EEG background reactivity to painful stimulation was tested.  They analyzed the association between cEEG findings and neurologic outcome, assessed at 2 months with the Glasgow-Pittsburgh Cerebral Performance Categories (CPC).  Continuous EEG recording was started 12 +/- 6 hours after CA and lasted 30 +/- 11 hours.  Non-reactive cEEG background (12 of 15 (75 %) among non-survivors versus none of 19 (0) survivors; p < 0.001) and prolonged discontinuous "burst-suppression" activity (11 of 15 (73 %) versus none of 19; p < 0.001) were significantly associated with mortality.  EEG seizures with absent background reactivity also differed significantly (7 of 15 (47 %) versus none of 12 (0); p = 0.001).  In patients with non-reactive background or seizures/epileptiform discharges on cEEG, no improvement was seen after TH.  Non-reactive cEEG background during TH had a positive predictive value of 100 % (95 % confidence interval (CI): 74 to 100 %) and a false-positive rate of 0 (95 % CI: 0 to 18 %) for mortality.  All survivors had cEEG background reactivity, and the majority of them (14 of 19 (74 %)) had a favorable outcome (CPC 1 or 2).  The authors concluded that cEEG monitoring showing a non-reactive or discontinuous background during TH is strongly associated with unfavorable outcome in patients with coma after CA.  Moreover, they stated that these data warrant larger studies to confirm the value of cEEG monitoring in predicting prognosis after CA and TH.

The National Institute for Health and Clinical Excellence’s clinical guideline on "The epilepsies: The diagnosis and management of the epilepsies in adults and children in primary and secondary care" (NICE, 2012) stated that  "Long-term video or ambulatory EEG may be used in the assessment of children, young people and adults who present diagnostic difficulties after clinical assessment and standard EEG".

The consensus of experts in a 2010 review was that effective treatment of infantile spasms is defined by complete cessation of spasms and resolution of hypsarrhythmia on electroencephalography (EEG) (Glaze, 2015; Pellock et al, 2010). Both parents and trained observers may miss the occurrence of spasms, especially if they are subtle. Less commonly, they may "over count" imitators of spasms, especially in infants and young children in the symptomatic group. A standard EEG to evaluate interictal activity may miss the hypsarrhythmia pattern, which can be variably present in an awake child, but is detected more sensitively in sleep. As a result, video-EEG monitoring is ideally used to assess treatment response in children with infantile spasms.

Duration of Continuous EEG Video Monitoring

Asano et al (2005) retrospectively reviewed the clinical utility of initial video-EEG monitoring in a series of 1,000 children suspected of epileptic disorders.  The ages of patients (523 boys and 477 girls) ranged from 1 month to 17 years (median age of 7 years).  The mean length of stay was 1.5 days (range of 1 to 10 days).  Outcomes were classified as: "useful-epileptic" (successful classification of epilepsy), "useful-non-epileptic" (demonstration of non-epileptic habitual events), "uneventful" (normal EEG without habitual events captured), and "inconclusive" (inability to clarify the nature of habitual events with abnormal inter-ictal EEG findings).  A total of 315 studies were considered "useful-epileptic"; 219 "useful-non-epileptic"; 224 "uneventful"; 242 "inconclusive".  Longer monitoring was associated with higher rate of a study classified as "useful-epileptic" in all age groups (Chi square test: p < 0.001).  In addition, longer monitoring was associated with lower rate of a study classified as "inconclusive" in adolescences (p < 0.001).  Approximately 50 % of the children with successful classification of epilepsy were assigned a specific diagnosis of epilepsy syndrome according to the International League Against Epilepsy (ILAE) classification.  These researchers found only 22 children with ictal EEG showing a seizure onset purely originating from a unilateral temporal region.  The authors concluded that video-EEG monitoring may fail to capture habitual episodes.  To maximize the utility of studies in the future, a video-EEG monitoring longer than 3 days should be considered in selected children such as adolescences with habitual events occurring on a less than daily basis.  These investigators recognized a reasonable clinical utility of the current ILAE classification in the present study.  It may not be common to identify children with pure unilateral temporal lobe epilepsy solely based on video-EEG monitoring.

Alving et al (2009) noted that inpatient long-term video-EEG monitoring (LTM) is an important diagnostic tool for patients with seizures and other paroxysmal behavioral events.  The main referral categories are diagnosis (epileptic versus non-epileptic disorder), seizure classification and pre-surgical evaluation.  The diagnostic usefulness of the LTM varies considerably (19 to 75 %) depending on how this was defined and on the selection of the patients.  These researchers evaluated the diagnostic usefulness and the necessary duration of the LTM for the referral groups, in patients extensively investigated before the monitoring.  An LTM was considered diagnostically useful when it provided previously not reported, clinically relevant information on the paroxysmal event.  For the pre-surgical group, reaching a decision concerning surgery was an additional requirement.  These investigators reviewed data from 234 consecutive LTM-sessions (221 patients) over a 2-year period.  In 44 % of the cases the LTM was diagnostically useful.  There were no significant differences concerning diagnostic usefulness among the main referral groups: diagnostic (41 %), classification (41 %) and pre-surgical (55 %).  Diagnostic usefulness did not differ among the age groups either.  The duration of the successful LTM-sessions was significantly longer in the pre-surgical group (mean of 3.5 days) than in the diagnostic and classification groups (2.4 and 2.3 days, respectively).  The authors concluded that LTM is a valuable diagnostic tool even in patients extensively investigated before the monitoring, and is equally effective in the referral and age groups.  However, patients referred for pre-surgical evaluation need considerably longer LTM, and this should be taken into account when planning the resources and calculating the costs.

Hupalo et al (2016) determined the optimal duration of the long-term video-EEG (LTM) and evaluated diagnostics utility of LTM in patients with epilepsy and other paroxysmal events in terms of future diagnosis and management.  These researchers carried out a retrospective analysis of 282 LTMs performed in the last 5 years in their Epilepsy Monitoring Unit (EMU), in 202 consecutive patients.  The analysis included demographic data, monitoring time, number and type of paroxysmal events, the time until their onset, influence of LTM result on the diagnosis and future management.  There were 117 women and 85 men, mean age of 34.2 years.  Mean duration of LTM was 5 days (range of 3 to 9), with 447 paroxysmal events recorded in 131 (65 %) patients.  Epileptic seizures were recorded in 82 % cases (in 11 % associated with psychogenic non-epileptic seizures (PNES)).  The remaining 18 % had either PNES (11 %), or parasomnias (7 %).  Only 15 % of epileptic seizures took place within the first 24 hours of the LTM (53 % and 32 % on the 2nd and 3rd day, respectively), whereas as many as 62 % of PNES did (while only 28 % and 10 % on the 2nd and 3rd day, respectively).  The LTM results changed the diagnosis in 36 % of the patients, most frequently in PNES (from 2 % to 14 %). Overall, it changed the management in 64 % of the patients, especially with PNES and those who underwent epilepsy surgery.  The authors concluded that LTM should last at least 72 hours in patients with refractory epilepsy; most of cases with PNES could be diagnosed after 48 hours.

Cox and colleagues (2017) noted that LTM aims to record the habitual event and is a useful diagnostic tool for neurological paroxysmal clinical events.  In the authors’ EMU setting, admissions are usually planned to last up to 5 days.  These investigators ascertained time taken for the recording of a first event and determined correlations between different clinical characteristics and timings.  They retrospectively reviewed diagnostic and classification LTM recording performed at a tertiary epilepsy center.  A total of 63 recordings were reviewed.  Most subjects (89 %) had events at least once-weekly before admission.  In 40 (63 %) a habitual event was recorded, mostly (93 %) within the first 2 days.  No events were recorded on day 4 or 5.  A few characteristics were associated with a trend for events occurring earlier (events more than once-weekly versus less than once-weekly, motor symptoms compared with aura or dyscognitive events, and reduction of anti-epileptic drugs versus no reduction).  The authors concluded that the findings of this study suggested that, for diagnostic event recording in people with epilepsy or psychogenic non-epileptic attacks (PNEA), a maximum recording time of 3 days is sufficient in 2/3 of them, if event frequency is at least once a week.  In the remaining 1/3, prolonged recording up to 5 days did not result in capturing a clinical event.  For these individuals, shorter admission could be planned, for example for 2 days rather than 5 days.

An UpToDate review on "Video and ambulatory EEG monitoring in the diagnosis of seizures and epilepsy" (Hirsch et al, 2017) states that "Duration of recording – The likelihood of recording an event (and therefore making a diagnosis) increases with the duration of recording.  In 1 case series of 248 adult patients admitted to an epilepsy monitoring unit, the median time to first diagnostic event, whether epileptic seizure or non-epileptic event, was 2 days; 35 % of patients required 3 or more days of monitoring, and 7 % more than 1 week.  In another series of consecutive patients admitted to a video-EEG monitoring unit for diagnosis of spells, a stay of longer than 5 days was no less likely to be inconclusive than shorter stays in patients with epileptic seizures.  In patients with presumed non-epileptic events, stays longer than 5 days were more likely to be inconclusive.  When a first video-EEG study is not diagnostic, repeat testing can be helpful; in 1 study a 2nd study was diagnostically useful in 35 of 43 cases.  The duration of recording will depend on the indication: subjects undergoing pre-surgical evaluation often require a significantly longer period of long-term monitoring to obtain clinically relevant (and previously unreported) information (mean of 3.5 days) compared to patients who are being recorded for diagnosis or classification (2.4 and 2.3 days, respectively)".  The duration of recording will depend on the indication:

• For patients undergoing pre-surgical evaluation – mean of 3.5 days.
• For patients being recorded for diagnosis or classification – 2.4 days and 2.3 days, respectively.
• Only a small percentage of patients (7 %) needs more than 1 week.

Mahfooz et al (2017) stated that continuous V-EEG is an important diagnostic and prognostic tool in newborns with HIE undergoing therapeutic hypothermia.  The optimal duration of continuous V-EEG during whole-body hypothermia is not known.  These researchers conducted a retrospective study of 35 neonates with HIE undergoing whole-body hypothermia with continuous V-EEG; EEG ictal changes were detected in 9/35 infants (26 %).  Of these 9 infants, the seizures were initially observed within 30 minutes of EEG monitoring in 6 (67 %), within 24 hours in 2 (22 %), and during re-warming in 1 infant (11 %).  No new seizures were detected between 24 to 72 hours of therapeutic hypothermia.  Background suppression was detected in 14 infants (40 %) by 24 hours.  The authors concluded that in neonates with HIE undergoing therapeutic hypothermia, continuous V-EEG has the highest diagnostic yield within the first 24 hours and during the re-warming phase.  Moreover, they noted that in the absence of prior seizures or anti-epileptic therapy, limiting continuous V-EEG to these periods in resource-limited settings may reduce cost during therapeutic hypothermia.

EEG Video Monitoring for Driving Clearance

Chen and colleagues (2014) noted that driving is an important part of everyday life for most adults, and restrictions on driving can place a significant burden on individuals diagnosed with epilepsy.  Although sensorimotor deficits during seizures may impair driving, decreased level of consciousness often has a more global effect on patients' ability to respond appropriately to the environment.  Better understanding of the mechanisms underlying alteration of consciousness in epilepsy is important for decision-making by people with epilepsy, their physicians, and regulators in regard to the question of fitness to drive.  Retrospective cohort and cross-sectional studies based on surveys or crash records can provide valuable information about driving in epilepsy.  However, prospective objective testing of ictal driving ability during different types of seizures is needed to more fully understand the role of impaired consciousness and other deficits in disrupting driving.  Driving simulators adapted for use in the epilepsy video-EEG monitoring unit may be well suited to provide both ictal and inter-ictal data in patients with epilepsy.  Objective information about impaired driving in specific types of epilepsy and seizures can provide better informed recommendations regarding fitness to drive, potentially improving the quality of life (QOL) of people living with epilepsy.  The authors concluded that presently there is a need to understand the impact of epilepsy on driving in both the ictal and inter-ictal periods.  In addition to broad retrospective studies analyzing the driving safety patterns of large cohorts, prospective ictal testing of people with epilepsy (PWE) is needed to understand acute effects of seizures on consciousness and driving ability.  They stated that prospective testing of driving ability in PWE also provides objective data on the impact of seizure-related pathology and/or anti-epileptic drugs on fitness to drive in the inter-ictal period.

Diagnosis of Brain Death

An UpToDate review on "Diagnosis of brain death" (Young, 2019) and the American Academy Neurology (AAN)’s position statement on "Brain death, the determination of brain death, and member guidance for brain death accommodation requests" (Russell et al, 2019) do not mention EEG video monitoring as a diagnostic tool.

Long-Term Video-EEG Monitoring in Epilepsy

Tatum et al (2022) provided recommendations on the indications and minimum standards for inpatient long-term video-electroencephalographic monitoring (LTVEM).  The Working Group of the ILAE and the International Federation of Clinical Neurophysiology (IFCN) developed guidelines aligned with the Epilepsy Guidelines Task Force.  These investigators reviewed published evidence using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement.  They found limited high-level evidence aimed at specific aspects of diagnosis for LTVEM performed to examine patients with seizures and non-epileptic events.  For classification of evidence, these investigators used the clinical practice guideline process manual of the AAN.  They formulated recommendations for the indications, technical requirements, and essential practice elements of LTVEM to derive minimum standards used in the evaluation of patients with suspected epilepsy using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation).  These researchers stated that further investigation is needed to obtain evidence regarding long-term outcome effects of LTVEM and establish its clinical utility.

van Griethuysen et al (2022) noted that pre-surgical LTVEM is an important part of the pre-surgical evaluation in patients with focal epilepsy.  Multiple seizures need to be recorded, often in limited time and with the need to taper anti-seizure medication (ASM).  In a systematic review, these investigators examined the yield (in terms of success), and risks associated with pre-surgical LTVEM, and identified all previously reported contributing variables.  These investigators carried out a systematic review of the databases of PubMed Medline, Embase, Cochrane Central, and the Cochrane Database of Systematic Reviews following the PRISMA guideline.  Publications regarding pre-surgical LTVEM reporting on variables contributing to yield and risk were included.  Study characteristics of all included studies were extracted following a standardized template.  Within these articles, studies presenting multi-variable analyses of factors contributing to the risk of adverse events (AEs) or the success of LTVEM were identified.  These researchers found 36 studies reporting on LTVEM, including 4,703 pre-surgical patients, both children and adults.  Pre-surgical LTVEM resulted in an average yield of 85 %; AEs occurred with an averaged total event rate of 17 %; however,  the type of included events was variable among studies.  Factors reported to independently contribute to successful LTVEM included baseline seizure frequency, a shorter interval from the most recent seizure, extra-temporal lobe epilepsy, and no requirement for ASM reduction.  Factors independently contributing to the occurrence of AEs were: ASM tapering, a history of status epilepticus, a history of focal to bilateral tonic-clonic seizures, psychiatric co-morbidity, and ASM taper rate.  The authors concluded that this study showed that the data on factors contributing to yield and risk of AEs was significant and variable, and often reported with inadequate statistics.  These investigators stated that future research is needed to develop guidelines for ASM withdrawal during pre-surgical video-EEG monitoring, taking pre-defined factors for success and risks of AEs into account.

Karakas et al (2023) noted that review of videos (without EEG) to differentiate epileptic seizures (ES) from non-epileptic spells (NES) may be helpful where epilepsy monitoring is not feasible.  Previous studies of video-based diagnosis have suffered from variable accuracy, sensitivity, and specificity.  In a systematic review and meta-analysis, these investigators examined available evidence in PubMed, Embase, and Web of Science from inception to September 2022, identifying studies that reported on the video-based diagnosis of ES and NES.  In primary analysis, for each study, the most expert group was chosen when different groups of reviewers classified the videos (e.g., epilepsy specialists and general neurologists).  In secondary analysis, these researchers compared the diagnostic accuracy of different expertise levels (e.g., epileptologists, general neurologists, residents, and medical students).  Meta-analysis was carried out to obtain pooled estimates of reliability measures.  A total of 5,245 studies identified, and 13 fulfilled the inclusion criteria, with cumulative data from 683 patients (696 videos) reviewed by 95 independent reviewers in primary analysis.  Video alone had a strong ability to differentiate ES from NES as evidenced by the following metrics -- area under the curve (AUC): 0.9 (considered "outstanding"); sensitivity: 82.2 % (95 % CI: 80.2 % to 84.0 %); specificity: 84.7 % (CI: 82.8 % to 86.5 %), and diagnostic odds ratio (DOR): 24.7 (CI: 11.5 to 52.9).  The secondary analysis showed reviewer-dependent accuracy with epileptologists showing the highest accuracy (DOR 81.2, CI: 90.0 % to 94.6 %).  The authors concluded that video alone exhibited reliable diagnostic performance for differentiating ES from NES.  Meta-analysis limitations entailed inter-study heterogeneity including variable video quality as well as reviewer expertise.  These investigators stated that combined video-EEG remains the gold standard for the differential diagnosis of ES and NES.

Evaluation of Seizure Severity and Treatment Response in Newborn Infants with Seizures

Herzberg et al (2022) sought to characterize intra-cranial hemorrhage (ICH) as a seizure etiology in infants born term and pre-term.  For infants born term, these investigators compared seizure severity and treatment response for multi-site versus single-site ICH and HIE with versus without ICH.  These researchers studied 112 newborn infants with seizures attributed to ICH and 201 infants born at term with seizures attributed to HIE, using a cohort of consecutive infants with clinically diagnosed and/or electrographic seizures prospectively enrolled in the multi-center Neonatal Seizure Registry.  They compared seizure severity and treatment response among infants with complicated ICH, defined as multi-site versus single-site ICH and HIE with versus without ICH.  ICH was a more common seizure etiology in infants born pre-term versus term (27 % versus 10 %, p < 0.001).  Most infants had sub-clinical seizures (74 %) and an incomplete response to initial ASM (68 %).  In infants born term, multi-site ICH was associated with more sub-clinical seizures than single-site ICH (93 % versus 66 %, p = 0.05) and an incomplete response to the initial ASM (100 % versus 66 %, p = 0.02).  Status epilepticus was more common in HIE with ICH versus HIE alone (38 % versus 17 %, p = 0.05).  The authors concluded that seizure severity was greater and treatment response was lower among infants born term with complicated ICH.  These data supported the use of continuous video-EEG monitoring to accurately detect seizures and a multi-step treatment plan that considers early use of multiple ASMs, especially with parenchymal and high-grade intra-ventricular hemorrhage and complicated ICH.

Evaluation of Neonatal Seizures

In a prospective, cohort study, Glass et al (2016) examined the contemporary etiology, burden, and short-term outcomes of seizures in neonates monitored with continuous video-electroencephalogram (cEEG).  These researchers collected data from 426 consecutive neonates (56 % male, 88 % term) 44 weeks or less post-menstrual age with clinically suspected seizures and/or electrographic seizures.  Subjects were assessed between January 2013 and April 2015 at 7 U.S. tertiary care pediatric centers following the guidelines of the American Clinical Neurophysiology Society (ACNS) for cEEG for at-risk neonates.  Seizure etiology, burden, management, and outcome were determined by chart review by the use of a case report form designed at study onset.  The most common seizure etiologies were HIE (38 %), ischemic stroke (18 %), and ICH (11 %).  Seizure burden was high, with 59 % having 7 or more electrographic seizures, and 16 % having status epilepticus; 52 % received 2 or more ASM.  During the neonatal admission, 17 %  died; 49 % of survivors had abnormal neurologic examination at hospital discharge.  In an adjusted analysis, high seizure burden was a significant risk factor for mortality, hospital length of stay (LOS), and abnormal neurological examination at discharge.  The authors concluded that in this large, contemporary profile of consecutively enrolled newborns with seizures treated at centers that use cEEG per the guidelines of the ACNS, about 50 % had high seizure burden, received 2 or more ASM, and/or died or had abnormal examination at discharge.  Greater seizure burden was associated with increased morbidity and mortality.  These investigators stated that these results underscored the importance of accurate determination of neonatal seizure frequency and etiology and a potential for improved outcome if seizure burden is reduced.

In a single-center study, Wietstock et al (2016) examined the diagnostic yield of cEEG monitoring in critically ill neonates in the setting of a novel, university-based Neonatal Neurocritical Care Service.  Patient demographic characteristics, indication for seizure monitoring, and presence of electrographic seizures were obtained by chart review.  Among 595 patients cared for by the Neonatal Neurocritical Care Service, 400 (67 %) received cEEG.  The median duration of cEEG monitoring was 49 (inter-quartile range [IQR] = 22 to 87) hours.  Electrographic seizures were captured in 105 of 400 (26 % of monitored patients) and of those, 25 of 105 (24 %) had no clinical correlate.  Furthermore, 52 of 400 subjects (13 %) were monitored due to paroxysmal events concerning for seizures, but never had electrographic seizures.  The authors concluded that cEEG monitoring helped confirm or rule out ongoing seizures in more than 1/3 of the cases.  These investigators stated that this finding helped to support the use of cEEG in critically ill neonates.

In a retrospective study, Sansevere et al (2017) determined the duration of cEEG monitoring needed to adequately capture electrographic seizures and EEG status epilepticus in the pediatric intensive care unit (PICU) using clinical and background EEG features.  This trial included patients aged 1 month to 21 years admitted to a tertiary PICU and undergoing cEEG (greater than 3 hours).  Clinical data collected included admission diagnosis, EEG background features, and time variables including time to 1st seizure after initiation of cEEG.  A total of 414 patients aged 4.2 (0.75 to 11.3) years (median, IQR) were included.  With a median duration of 21 (16 to 42.2) hours of cEEG monitoring, these researchers identified electrographic seizure or EEG status epilepticus in 25 % of subjects.  They identified 3 features that could improve the efficiency of cEEG resources and provide a decision-making framework.  First, clinical history of acute encephalopathy was not predictive of detecting electrographic seizure or EEG status epilepticus, whereas a history of status epilepticus or seizures was.  Second, normal EEG background or absence of epileptiform discharges in the initial 24 hours of recording informed the decision to discontinue cEEG.  Third, failure to record electrographic ictal events within the first 4 to 6 hours of monitoring may be sufficient to predict the absence of subsequent ictal events.  The authors concluded that individualized monitoring plans are needed to increase seizure detection yield while improving resource utilization.  A strategy using information from the clinical history, initial EEG background, and the first 4 to 6 hours of recording may be effective in determining the necessary duration of cEEG monitoring in the PICU.

Griffith et al (2020) stated that cEEG monitoring of critically ill infants and children has expanded rapidly in recent years.  Indications for cEEG include evaluation of patients with altered mental status, characterization of paroxysmal events, and detection of electrographic seizures, including monitoring of patients with limited neurological examination or conditions that put them at high risk for electrographic seizures (e.g., cardiac arrest or extra-corporeal membrane oxygenation [ECMO] cannulation).  Depending on the inclusion criteria and clinical characteristics of the population studied, the percentage of pediatric patients with electrographic seizures varies from 7 % to 46 % and with electrographic status epilepticus from 1 % to 23 %.  There is also evidence that epileptiform and background cEEG patterns may provide important information regarding prognosis in certain clinical populations.  Quantitative EEG techniques are emerging as a tool to enhance the value of cEEG to provide real-time bedside data for management and prognosis.  The authors concluded that continued research is needed to understand the clinical value of seizure detection and identification of other cEEG patterns on the outcomes of critically ill infants and children.

On behalf of the Study Group of Intensive and Integrated Care for Pediatric Central Nervous System (iCNS Group) at Chang Gung Children's Hospital in Taoyuan, Taiwan,  Chen et al (2022) stated that neonatal encephalopathy is caused by a wide variety of acute brain insults in newborns and presents with a spectrum of neurologic dysfunction, such as consciousness disturbance, seizures, and coma.  The increased excitability in the neonatal brain appears to be highly susceptible to seizures after a variety of insults, and seizures may be the 1st clinical sign of a serious neurologic disorder.  Subtle seizures are common in the neonatal period, and abnormal clinical paroxysmal events may raise the suspicion of neonatal seizures; and cEEG monitoring is the gold standard for the diagnosis of neonatal seizures.  These investigators identified the prevalence of electrographic seizures and the impact of monitoring in neonates with a high risk of encephalopathy.  They carried out a prospective, cohort study in a tertiary neonatal intensive care unit (NICU) over a 4-year period.  Neonates with a high risk of encephalopathy who were receiving cEEG monitoring were eligible.  Subjects were divided into 2 groups: acute neonatal encephalopathy (ANE), and other high-risk encephalopathy conditions (OHRs).  The neonates’ demographic characteristics, etiologies, EEG background feature, presence of electrographic seizures, and the impact of monitoring were analyzed.  A total of 71 neonates with a high risk of encephalopathy who received cEEG monitoring were enrolled.  In this consecutive cohort, 42 (59.2 %) were monitored for ANE, and 29 (40.8 %) were monitored for OHRs.  At the time of starting EEG monitoring, 54 (76.1 %) of the neonates were term infants.  The median gestational age at monitoring was 39 weeks (IQR, 37 to 41 weeks).  The median total EEG monitoring duration was 64.7 hours (IQR, 22.2 to 72.4 hours).  Electrographic seizures were captured in 25 of the 71 (35.2 %) neonates, of whom 20 (80 %) had electrographic-only seizures without clinical correlation.  In addition, of these 20 neonates, 13 (65 %) developed electrographic status epilepticus.  Electrographic seizures were most commonly found in the ANE group (17, 40.5 %) than in the OHRs group (8, 27.6 %) (p = 0.013).  Furthermore, normal/mild abnormality and inactive EEG background were less electrographic seizure than moderate and major abnormality EEG background (2 of 30, 6.7 % versus 23 of 41, 56.1 %, p < 0.001).  Lastly, cEEG monitoring excluded the diagnosis of electrographic seizures in 2/3 of the monitored neonates who had paroxysmal events mimicking seizures and resulted in a change in clinical management in 39.4 % of the neonates.  The authors concluded that these findings demonstrated that cEEG monitoring could accurately detect seizures, and that it could be used to guide seizure medication management; thus, cEEG monitoring has important clinical management implications in neonates with a high risk of encephalopathy.

Furthermore, an UpToDate review on “Clinical features, evaluation, and diagnosis of neonatal seizures” (Shellhaas, 2024) states that “Video EEG monitoring -- The gold standard for neonatal seizure diagnosis is multi-channel video continuous EEG (cEEG) monitoring.  Since this testing is specialized and resource-intensive, it should be reserved for newborns at highest risk for seizures.  There are many examples of high-risk clinical scenarios, but in general cEEG monitoring should be considered for newborns with proven or suspected acute brain injury and comorbid encephalopathy, even if there are no clinical events suspicious for seizures.  In an observational study, the probability of successful initial treatment for acute seizures was greater for 161 neonates who had cEEG monitoring for the indications of encephalopathy or pharmacologic paralysis (i.e., a screening cEEG) compared with 353 neonates who had cEEG monitoring for the indication of suspected seizures (i.e., a confirmatory cEEG) (39 % versus 18 %)”.

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