Symptomatic epilepsy – identifiable cerebral
cause.
• Cryptogenic epilepsy – non-identifiable cause
in a patient with neurological deficits or cognitive
impairment
– Infantile spasms
– LGS (Lennox-Gastaut syndrome)
– Myoclonic astatic epilepsy of Doose
• Idiopathic epilepsy – non-identifiable cause in
an entirely normal patient
– juvenile myoclonic epilepsy
– benign partial epilepsy of childhood with
centrotemporal spikes
– benign partial epilepsy of childhood with occipital
paroxysms
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Important Epilepsy Syndromes:
West syndrome – Triad of:
– hypsarrhythmia on EEG
– infantile spasms
– developmental retardation or regression
Presents in 6-18 month infants and is treated with ACTH or vigabatrin.
Lennox-Gastaut Syndrome (LGS) – Infantile spasms and West syndrome frequently transform into LGS
becoming a life-long epileptic encephalopathy. It consists of:
– atonic seizures
– tonic seizures
– atypical absence seizures associated with mental retardation and a characteristic EEG pattern.
Typical onset of LGS is between 3-5 years of age. EEG shows an abnormally slow background and diffuse slow
spike and slow wave (<2.5 Hz) activity due to generalized encephalopathy.
Childhood Absence Epilepsy – occurs between 3-5 years of age and remits by ages 10-12 years. Frontally
dominant EEG showing normal background for age and 3-Hz generalized spike and wave discharges. Usually 4
Hz at the onset of the absence seizures and may slow to 2.5 Hz at the end of a seizure.
Benign partial epilepsy syndromes of childhood – there are two important types:
– Benign rolandic epilepsy (BRE) or Benign partial epilepsy of childhood with centrotemporal spikes – onset is
between 3-10 years with history of orobuccal numbness on one side of the mouth or with a tingling sensation
on one side of the face. EEG shows frequent spike and wave discharges in the centrotemporal region.
– Benign partial epilepsy of childhood with occipital paroxysms (BPEOP) – similar to BRE but the discharges
are located in the occipital part of brain.
Juvenile Myoclonic Epilepsy (JME)- the most common epilepsy syndrome presenting with generalized tonicclonic seizures in an other-wise neurologically normally patient aged 12-30 years. Photosensitivity is present in at
least 30% of patients.
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Clue words for the boards:
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slow spike and wave activity = LGS
diffuse 3-Hz spike and wave activity = benign absence epilepsy
fast spike and wave (>2.5 Hz) activity = benign myoclonic types of epilepsy
hyperarrhythmia = infantile spasms
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Syncope;
Transient ischaemic attack (TIA);
Transient global amnesia;
Panic attack;
Episodic vertigo;
Stroke;
Migraine;
Memory disturbance and/or confusion; and
Restless legs syndrome
Seizure
Syncope
TIA
Transient global
Panic attack
amnesia
Premonition
None or Aura symptoms
None; or
Lightheadedness
Nausea
Vomiting
Diaphoresis
Pallor
Palpitations
None
Lightheadedness
Nausea
Vomiting
Diaphoresis
Panic, fear
Sleep deprivation
Flashing lights
Postural change
Neck movements
Prolonged standing
Exercise
None
Stress Social situations
Acute
Variable
Acute
Acute
Acute
1-2 minutes
Seconds-minutes
Minutes-hours
Hours
Variable
Variable tonic clonic
movements depending
upon where seizure
affects brain
Loss of tone
Clonic jerking
Physical deficits
dependant upon where
occurs
None
None or
Pacing
Agitation
Rapid breathing
Stiffening of hands
Variable
Occasional
None
None
None
Increased or decreased
Variable
Normal
Normal
Increased
Confusion Sleep
Alert or mild confusion
Alert
Alert
Alert
Symptoms
Precipitating
Factors
Onset
Duration
Movements
Incontinence
Heart rate
Postictal
• 50% of patients
• Depression, Anxiety and Psychotic
disturbances
• These psychiatric disturbances can be
classified according to how they relate in
time to seizure occurrence,
• ictal
• periictal(preictal/prodromal, postictal)
• interictal.
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Treatmentrelated psychiatric problems
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Antiepileptic drugs
most commonly depression, anxiety, behavioural or cognitive problems and,
in rare cases, psychosis.
Phenobarbitone, primidone, tiagabine, topiramate, vigabatrin and felbamate
have
been associated with depression.
Psychosis is a rare complication of a number of AEDs such as vigabatrin
and topiramate.
Improved seizure control has been associated with the emergence of
psychiatric symptoms.
Landolt introduced the term ‘forced normalisation’ which refers to a
dramatic reduction in epileptiform activity on EEG being associated with the
emergence of psychosis or sometimes behavioural/mood disturbances.
This phenomenon has been reported with most AEDs and therefore any
new drug should be started at low doses and increased slowly. The risk may
be higher in patients who are on polytherapy, become seizure free abruptly,
or if there is a past psychiatric history.
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• Epilepsy surgery
• Transient mood disturbances (emotional lability,
depression and anxiety) have been reported following
temporal lobe surgery for epilepsy (about 25%) in the
first 6-12 weeks.
• in some patients (10%), symptoms, particularly
depression, may persist and require psychiatric
treatment.
• There are also reports of de novo psychosis arising after
surgery and it has been suggested that it is more
common with right sided temporal lobe surgery.
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It is therefore important for pre and postsurgical
MAGNETIC RESONANCE IMAGING (MRI): Each patient with
new-onset epilepsy should have an MRI (temporal angulation,
T1,T2, FLAIR, coronal and axial) to detect structural lesions caused
by for example cortical malformation, traumatic brain injury, brain
tumor, and cerebrovascular disease, which are the most common
causes of symptomatic epilepsy. Contrast media, inversion recovery,
fast field echo and 3D only in special cases. Even in idiopathic
epilepsy, MRI is recommended to diagnose unsuspected dual
pathology as discussed above.
ELECTROENCEPHALOGRAM (EEG): Each patient with newonset
epilepsy should have an EEG. EEG is most valuable within 24
h of the seizure. Information gain is optimal up to the 4th EEG, if no
paroxysmal interictal discharges are found, repeat EEG during
sleep. 24-hour EEG most meaningful in a patient with frequent
seizures who can be expected to have seizures during the 24 h
recording. Interictal EEG discharges may support the diagnosis of
the epilepsy syndrome.
COMPUTER TOMOGRAM (CCT): Computer tomograms are
obsolete, except to detect fractures or hemorrhage in an emergency
situation.
HEAD X-RAY: obsolete
CLINICAL CHEMISTRY: routine work-up, creatinkinase, Vitamin
B6 if seizures are unresponsive to AEDs, even in adults. CSF, only
when infectious disorders are suspected. Creatinkinase increased
within 12-24 h, prolactin increased within 30 min.
SINGLE-PHOTON- EMISSION -TOMOGRAM (SPECT) and
POSITON- EMISSION-TOMOGRAM (PET), MAGNETO
ENCEPHALOGRAPHY (MEG): only for presurgical work-up or
scientific studies.
Suggested MRI protocols for epilepsy patients (standard investigations)
Temporal lobe epilepsy
1. Hippocampal oriented T2-weighted (coronal + axial)
2. Hippocampal oriented fluid-attenuated inversion recovery (FLAIR) (coronal + axial)
3. Isotropic T1-weighted three-dimensional sequence (MPRage)
4. (Gadolinium contrast-enhanced T1-weighted image if non-contrast-enhanced image is
inconclusive)
5. T2*-weighted sequence
Extratemporal lobe epilepsy
1. AC–PC oriented T2-weighted (coronal + axial)
2. AC–PC oriented FLAIR (coronal + axial)
3. Isotropic T1-weighted three-dimensional sequence (MPRage)
4. (Gadolinium contrast-enhanced T1-weighted image if non-contrast-enhanced image is
inconclusive)
5. T2*-weighted sequence
Special protocols: Rationale
1. T2 relaxometry hippocampal signal abnormalities
2. Magnetic resonance spectroscopy detection of metabolic abnormalities
3. Diffusion tensor imaging (DTI) investigation of fiber tracts
4. Functional MRI investigation of eloquent cortical areas
5. Three-dimensional sequences automated voxel-based analyses
6. Magnetic resonance angiography investigation of brain vascularization