What is Long-Term EEG Monitoring (LTM EEG)?
Long-Term EEG Monitoring (LTM) is an extended form of electroencephalogram (EEG) testing that records a patient’s brain activity over several hours to several days, often with simultaneous video recording. It is used when brief EEGs are not sufficient to capture abnormal brain activity, especially in patients with seizures or unexplained episodes.
For patients requiring extended evaluation, we offer ambulatory long-term EEG monitoring. This
service allows us to capture brain activity over several hours to days to evaluate better intermittent
events like seizures or episodes of altered awareness.
Purpose of Long-Term EEG Monitoring
LTM is primarily used to:
- Diagnose or confirm epilepsy.
- Differentiate seizures from other events (e.g., fainting, tics, or psychogenic nonepileptic seizures).
- Determine seizure type and origin (focal vs. generalized).
- Evaluate seizure frequency and severity.
- Monitor brain activity in intensive care settings (e.g., after trauma or surgery).
- Assess response to treatment.
How It Works
| Step | Description |
|---|---|
| Electrode Placement | Electrodes are attached to the scalp with adhesive or conductive paste. |
| Video Recording | A camera continuously records physical behavior to correlate with brain wave activity. |
| Data Recording | EEG signals are recorded for 24–72 hours (sometimes longer). |
| Environment | Done in a hospital, epilepsy monitoring unit (EMU), or sometimes at home (ambulatory LTM). |
| Triggers | Patients may be asked to reduce sleep or medications to increase the chance of a seizure during monitoring. |
Types of LTM EEG
| Type | Description |
|---|---|
| Inpatient LTM | Done in a specialized hospital unit with round-the-clock observation. |
| Ambulatory LTM | Performed at home with portable EEG equipment and wearable video. |
What It Detects
- Seizure onset zone (important for epilepsy surgery planning)
- Non-epileptic events (e.g., psychogenic seizures)
- Silent seizures (without physical symptoms)
- Status epilepticus (continuous or rapidly repeating seizures)
- Brain activity changes during sleep or altered consciousness
Patient Experience
- Electrodes stay attached for the entire recording period.
- You may have limited mobility, especially during inpatient LTM.
- The goal is to safely capture typical events (e.g., seizures) on both EEG and video.