01
Suspected seizures or convulsions
To look for electrical patterns that may support the assessment of a seizure disorder when interpreted with the event description.
Electroencephalography • Brain Electrical Activity Recording
EEG Test in Cairo (Electroencephalogram)
An EEG records the brain’s electrical activity and can help a neurologist assess seizures and selected neurological events.
An EEG is a non-invasive test in which small electrodes are placed on the scalp to record the brain’s electrical signals. The test itself does not send electricity into the body and does not use ionizing radiation. The type and duration of recording depend on the clinical question and the patient’s needs.
Non-invasive
Records signals only
Duration depends on type
Direct answer
What is an EEG (electroencephalogram)?
An EEG, or electroencephalogram, records electrical activity from the brain through electrodes placed on the scalp. A neurologist reviews the waveforms, their distribution and timing, and interprets them in the context of the reason for testing, symptoms and medical history.
One of the best-known uses of an EEG is to support the assessment of seizures and epilepsy. It may also be used in selected cases involving altered awareness, events during sleep or other neurological questions determined by the treating clinician.
Important: an EEG measures electrical brain function during the recording period. It does not replace MRI or CT; each test answers a different clinical question.
What does it measure?Electrical brain activity displayed as waveforms and time-based patterns.
Does it send electricity?No. External electrodes detect and record electrical signals.
Does it use radiation?No X-rays or ionizing radiation are used.
Can the result diagnose a condition by itself?No. The result is interpreted with the event description, examination and other medical information.
When might a neurologist consider the test?
When an EEG test may be useful
Not every neurological symptom requires an EEG. The decision depends on the event, the clinical context and the specific question the clinician is trying to answer.
02
Loss or alteration of awareness
Especially when episodes recur or their nature cannot be clarified from history alone.
03
Staring spells or brief unresponsiveness
An EEG may be requested when short recurring events need to be distinguished from other causes.
04
Events occurring during sleep
EEG or Video EEG can be useful for selected nighttime events, while sleep-breathing disorders may require a sleep study (PSG).
05
Follow-up in selected epilepsy cases
It may be used in specific circumstances to review electrical patterns or answer a defined diagnostic or management question.
06
Selected hospital situations
Continuous EEG monitoring may be used in some patients with impaired consciousness or suspected seizures that are not clinically obvious.
The type depends on the clinical question
Types of EEG tests
It is useful to separate recording method and duration from the patient’s age or testing location. Children, for example, may undergo different EEG types depending on the clinical need.
Linking an event to the EEG recording
Video EEG
Video EEG combines an EEG recording with synchronized video. It can help the neurologist compare what happens during an event with electrical changes recorded at the same moment.
How Video EEG is interpreted →A common first recording
Routine EEG
A relatively shorter recording, often while awake. It may include opening and closing the eyes, deep breathing or flashing-light stimulation when appropriate.
To capture sleep or add information
Sleep or sleep-deprived EEG
A clinician may request sleep recording or a sleep-deprived EEG when sleep could provide additional information or when events are related to sleep.
Longer recording time
Prolonged EEG
The recording may continue for hours or longer when events are intermittent or when a longer sample of wake and sleep activity is needed.
Portable recording for suitable cases
Ambulatory / home EEG
A portable recorder may be used in selected cases to record brain activity for longer periods outside the laboratory, depending on the required setup and suitability of the patient.
Home EEG details →How is the EEG type selected?
A longer recording is not automatically “better”; the appropriate type is the one that can answer the clinical question.
Routine
Events or seizures needing an initial assessment
A sample of electrical brain activity that may include wakefulness and sometimes sleep.
Sleep / sleep-deprived
When sleep may reveal useful additional information
Increase the opportunity to record patterns that may not appear in a short awake recording.
Prolonged or Video EEG
Events are intermittent or their nature is unclear
Increase observation time and, when video is used, correlate a clinical event with the EEG recording.
Ambulatory / home
Selected cases needing longer recording outside the laboratory
Record brain activity during usual daily activity using portable equipment and the appropriate protocol.
What happens during the test?
How an EEG test is performed step by step
The details vary by recording type, but the general process is straightforward.
1
Scalp preparation
The head is measured, electrode positions are identified and electrodes are attached using suitable conductive paste or adhesive.
2
Recording begins
The electrodes detect electrical signals while the patient sits or lies down quietly.
3
Activation procedures if appropriate
The team may ask the patient to open and close the eyes, breathe deeply or look at a flashing light when clinically appropriate.
4
Review and interpretation
The recording is reviewed and the waveforms are interpreted in relation to symptoms, medical history and any synchronized video.
Before your appointment
How to prepare for an EEG test
Final instructions depend on the EEG type. Do not stop medication or reduce your sleep on your own; follow the instructions provided for your specific appointment.
What should you do before an EEG?
- Wash your hair and keep it clean and dry, without oils, gel or styling products.
- Bring a list of your current medicines and supplements.
- Take your usual medicines unless your clinician has specifically told you otherwise.
- Eat normally unless you have been given different instructions.
- If a sleep or sleep-deprived EEG is planned, follow the permitted sleep schedule exactly.
- Ask about caffeine; some EEG protocols require avoiding it for several hours before the test.
Things that can affect recording quality
- Continuous movement or tensing facial and scalp muscles during the recording.
- Hair oils, gels or styling products that reduce electrode contact quality.
- Not following sleep instructions when a sleep-deprived EEG is requested.
- Stopping medication or changing doses without medical guidance.
- Not telling the team about a recent event or seizure that may be relevant to interpretation.
Understanding the report
What do EEG results mean?
The report describes patterns seen during the recording. Their meaning depends on the clinical situation, so an EEG result should be interpreted in context rather than in isolation.
What does the neurologist look for?
The neurologist reviews the background electrical activity, distribution across the scalp, changes during sleep or activation procedures and patterns that may have clinical significance.
With Video EEG, electrical changes can be compared with what appears on video at the same time, which can be helpful when the nature of events is unclear.
Read common EEG result questionsDoes an “abnormal EEG” automatically mean epilepsy?
Not necessarily. Some changes may be nonspecific or related to age, sleep or the clinical context. Epilepsy is not diagnosed from the EEG alone.
The next step may be clinical follow-up, a longer recording, Video EEG, imaging or another investigation depending on the case.
See when EEG may be requestedDifferent tests answer different questions
EEG vs CT vs MRI
These tests are not substitutes for one another. A clinician selects them because each provides a different kind of information.
EEG
Electrical function
Records electrical brain activity over time and is particularly relevant to selected seizure and altered-awareness evaluations.
CT
Rapid structural imaging
Uses X-rays to show brain structure and is useful in different clinical settings, including selected urgent situations.
MRI
Detailed structural imaging
Uses a magnetic field and radio waves to image tissues. It may be requested alongside EEG when structural information is needed.
For infants and children when medically indicated
EEG for children: preparation should match the child’s age
Hair usually does not need to be cut, and the electrodes do not send electricity into the head.
Children may undergo a routine EEG, sleep EEG or a longer recording depending on the clinical question. In some cases, sleep preparation is one of the most important parts of planning the appointment.
- Explain that small sensors will be placed on the head to record signals.
- Follow age-specific sleep instructions and do not reduce sleep without guidance.
- Bring a familiar comfort item if the testing team says this is appropriate.
Portable recording for suitable patients
Home and prolonged EEG in Cairo
Home EEG is not simply moving a short test into a house; selected patients may need longer recording in a more natural environment.
Ambulatory or home EEG can be considered in selected cases, particularly when a longer recording is needed or travel is difficult. Recording quality, equipment and the clinical question determine whether a home setting is suitable.
- Confirm the required recording type and duration before the appointment.
- Clarify whether synchronized video is part of the planned recording.
- Follow instructions for protecting the electrodes and equipment throughout the recording.
Video explanation
EEG videos from Dr. Karim Ashraf
These videos are supplementary educational material and do not replace medical assessment or the preparation instructions for your specific EEG appointment.
Why is an EEG performed?
A video explanation of the role of EEG in recording electrical brain activity and situations in which a clinician may request it.
Open on YouTube →Preparing for an EEG
Preparation guidance and why instructions may vary depending on the EEG type.
Open on YouTube →EEG testing in Cairo
Book an EEG test in Cairo with NeuroVisit
Before booking, tell the team why the EEG was requested, the patient’s age and whether the request specifies a routine, sleep, prolonged or Video EEG. This helps the team confirm the appropriate setup instead of booking the wrong type of recording.
Heliopolis
50 Hegaz Street, Cairo
Contact the team before visiting to confirm appointment availability and the EEG type available at the location.
Confirm Heliopolis booking →Nasr City
Clinics Building, Dar Al Fouad Hospital — Nasr Road
Confirm the branch, appointment and required recording setup when booking.
Confirm Nasr City booking →Suitable cases
Home / ambulatory recording
Ask the team about home coverage and the equipment required for the requested EEG type.
Home EEG information →Interpretation matters as much as the waveform
EEG with Dr. Karim Ashraf
The role of an EEG is to add useful information to the clinical assessment, then connect the report to symptoms and the follow-up plan.
- Consultant Neurologist.
- Doctorate in Neurology — Faculty of Medicine, Ain Shams University.
- Training and certification in neurophysiology from Cleveland Clinic.
- Certification in advanced epilepsy treatment from the ILAE.
- Neurology certification from UCSF.
Related information
Continue by test type, symptoms or next step
Use these links to move directly to the most relevant part of this guide or to booking and broader neurology care information.
Questions patients ask before the appointment
Frequently asked questions about EEG tests
Is an EEG painful?
Usually not. Electrodes are placed on the scalp to record electrical signals and do not deliver electrical shocks. Some people may notice mild discomfort when electrode sites are cleaned or adhesive is removed.
Do I need to cut or shave my hair before an EEG?
An EEG usually does not require shaving the hair. Hair should be clean and dry without oils, gel or styling products.
How long does an EEG take?
It depends on the type. A routine EEG is relatively shorter, while sleep, prolonged or Video EEG recordings may take hours or longer. Ask the team about the expected duration of your planned test.
Do I need to fast before an EEG?
Fasting is not required for many EEG tests, but follow the instructions provided for your appointment because preparation can differ by test type and medical situation.
Should I stop epilepsy medication before an EEG?
Do not stop medication or change a dose on your own. Take your medicines as usual unless your clinician or testing team has given you clear, specific instructions.
Should I avoid caffeine before an EEG?
Some protocols ask patients to avoid coffee, tea or energy drinks for several hours, especially when sleep recording is planned. Follow the instructions for your appointment.
Does a normal EEG rule out epilepsy?
No. An EEG records a limited period and relevant electrical patterns may not appear during that time. A normal EEG alone does not rule out a previous seizure or epilepsy; clinical history and other evaluation remain important.
What is the benefit of Video EEG?
Synchronized video allows the neurologist to compare movements, behavior or symptoms during an event with electrical brain activity recorded at the same moment.
Can children have an EEG?
Yes, when medically indicated. The recording type, sleep instructions and preparation are adjusted to the child’s age and the reason for testing.
What is the difference between an EEG and a sleep study (PSG)?
EEG focuses on electrical brain activity. A polysomnography sleep study records several physiological signals during sleep and may include EEG together with breathing, oxygen levels, eye movements and muscle activity depending on the study.
Can an EEG be performed at home?
For selected patients and recording types, yes, when the clinical goal, equipment and setup allow it. Home testing is not suitable for every case.
When will I receive my EEG result?
Reporting time depends on recording duration, complexity and review method. Prolonged recordings and Video EEG generally require more review than a short recording. Ask the team for the expected reporting time for your test.
Not sure which EEG type was requested?
Send the test name written on the medical request, or a clear photo of the request, and the team can help you confirm the required preparation before booking.