A 19-year-old man presents with intractable generalized tonic-clonic (GTC) seizures, which worsen with sleep deprivation. He also reports morning twitching and jerks while taking carbamazepine. Additionally, he experienced muscle twitching during his EEG when exposed to flashing lights.
What are the expected EEG findings?
Choose the correct option:
A. Generalized 4- to 6-Hertz (Hz) polyspike and wave discharges with a photoconvulsive response
B. Generalized 3-Hz spike and wave discharges
C. Generalized 2.0-Hz spike and wave discharges
D. Left temporal focal epileptiform discharges
The correct answer and explanation is :
The correct answer is A. Generalized 4- to 6-Hertz (Hz) polyspike and wave discharges with a photoconvulsive response.
Explanation:
This patient’s presentation is suggestive of juvenile myoclonic epilepsy (JME), a common type of epilepsy that often begins in adolescence. The clinical features include:
- Intractable generalized tonic-clonic seizures (GTC) that worsen with sleep deprivation: This is characteristic of JME, as seizures in JME often occur shortly after waking up, particularly in the morning, and can be triggered by sleep deprivation.
- Morning twitching and jerks: These are likely myoclonic jerks, which are another hallmark of JME. These jerks typically occur shortly after waking and can be mistaken for normal muscle twitches, but they are actually seizures.
- Muscle twitching during the EEG with flashing lights: This refers to a photoconvulsive response, which is commonly seen in JME patients. They are sensitive to flickering lights, which can induce seizures or muscle twitches during an EEG.
EEG Findings in Juvenile Myoclonic Epilepsy (JME):
- Generalized 4- to 6-Hertz polyspike and wave discharges: This pattern is classic for JME. The discharges consist of a burst of rapid spikes (polyspikes) followed by a slow wave, and they typically occur in a generalized fashion, meaning they involve both hemispheres of the brain.
- Photoconvulsive response: Patients with JME are sensitive to visual stimuli, such as flashing lights or strobe lights, which can induce seizures or myoclonic jerks, and this response is often captured during an EEG with photic stimulation.
Why other options are incorrect:
- B. Generalized 3-Hz spike and wave discharges: This pattern is characteristic of absence seizures, which are a different type of generalized epilepsy. Absence seizures typically present with brief, sudden lapses in consciousness and are not associated with myoclonic jerks or GTC seizures.
- C. Generalized 2.0-Hz spike and wave discharges: This pattern is also characteristic of absence seizures but is even slower than the 3-Hz pattern. It is not typical of JME.
- D. Left temporal focal epileptiform discharges: This suggests a focal epilepsy, which typically results in focal seizures. The patient’s generalized tonic-clonic seizures and myoclonic jerks, along with the response to photic stimulation, indicate generalized epilepsy, not focal seizures.
In conclusion, juvenile myoclonic epilepsy is the most likely diagnosis, and the expected EEG findings include generalized 4- to 6-Hz polyspike and wave discharges with a photoconvulsive response, which fits the clinical presentation described in the question.