Epilepsy- 1 - Free MCQ Practice Test with solutions, NEET PG Medicine

The clinical information presented in the inquiry includes:

• Single type of seizure with satisfactory control
• No family history indicated
• Normal EEG results

In this clinical context, it is appropriate to consider discontinuing therapy after a duration of two years. Juvenile myoclonic epilepsy tends to manifest in the adolescent age group; however, the seizures typically occur upon awakening and are generally characterised by myoclonic jerks or grand mal seizures (GTCS). While some instances may present with absence seizures, focal seizures are not observed in cases of juvenile myoclonic epilepsy.

Harrison states that 'approximately 35% of drinkers and a significantly larger percentage of alcoholics experience a blackout'. This refers to a period of temporary antegrade amnesia during which the individual forgets all or part of the events that occurred during a night of drinking. You may have encountered numerous such instances in your emergency department as well.

Another effect of alcohol consumption is impaired judgement and coordination. Neuroimaging studies show evidence of cerebellar atrophy.

A concussion, or mild traumatic brain injury, is characterised as a blow to the head that leads to:

• Loss of consciousness for less than 30 minutes (ranging from a few seconds to several minutes)
• Altered consciousness for less than 24 hours (commonly under 30 minutes)
• Post-traumatic amnesia lasting less than 24 hours (typically under 30 minutes)
• Glasgow Coma Scale score of 13-15
• No focal neurological signs or only transient ones
• Normal neuroimaging results

While concussion is a plausible diagnosis, there are several factors that argue against it:

• According to Harrison, concussions are primarily observed in military veterans rather than in alcoholics.
• Loss of consciousness in concussions typically lasts only seconds or minutes, whereas in this case, the individual was asleep due to alcohol intoxication.
• Post-traumatic amnesia generally lasts less than 30 minutes.

A sudden cessation of AED can result in the onset of breakthrough seizures. Therefore, the medication should be gradually reduced.

• As the dose of levetiracetam is decreased over a period of 2 - 3 months, a second medication must be introduced slowly.
• Levetiracetam is indicated for focal onset seizures, administered at a dosage of 1000-300 mg/day.
• Therapeutic concentrations range from 5 - 45 µg/dl.
• Common side effects include sedation, fatigue, incoordination, mood alterations, anaemia, and leukopenia.

Myoclonus is characterised by quick, shock-like jerky movements that involve single or repeated muscle contractions. Types of myoclonus include:

• Action myoclonus: Happens during voluntary movement.
• Reflex/startle myoclonus: Triggered by external stimuli such as a loud noise.
• Negative myoclonus: Also known as Asterixis or flapping tremors.
• Hypnogogic jerks: Occur in healthy individuals as they fall asleep in NREM1.

Mesial temporal sclerosis is linked to a reduced seizure threshold and a background of febrile seizures from childhood.

It represents the most prevalent syndrome correlated with focal seizures exhibiting dyscognitive characteristics in adults.

• Auras frequently occur, often presenting as behavioural arrest, such as staring.
• Complex automatisms accompanied by postictal disorientation are observed.

MRI scans reveal hippocampal sclerosis.

• Resection of the antero-medial temporal lobe or a limited excision of the hippocampus and amygdala (known as Amygdalohippocampectomy).
• Focal seizures can potentially be eliminated through focal neocortical resection, involving the precise removal of a specific lesion (termed Lesionectomy).

It is justifiable to discontinue AED after a duration of 2 years for a patient who satisfies the following conditions:

• Complete medical control for 1-5 years
• Single seizure type, such as focal or GTCS
• Normal neurological examination
• Normal cognitive function
• Normal EEG

Lennox-Gastaut syndrome presents a triad of features:

• Various seizure types (commonly involving generalized tonic­clonic, atonic, and atypical absence seizures)
• EEG displaying slow (<3 Hz) spike-and-wave discharges along with a range of other irregularities
• Cognitive impairment in the majority, though not in every instance

The syndrome is multifactorial in nature and is linked to central nervous system diseases or dysfunctions, developmental anomalies, and perinatal hypoxia/ischemia.

• levetiracetam
• topiramate
• lamotrigine
• valproic acid
• lacosamide

Menstrual irregularities and PCOD are adverse effects of valproate observed in women. The most prevalent side effects include:

• Temporary gastrointestinal issues
• CNS effects such as sedation, ataxia, and tremors

A rare complication is fulminant hepatitis.

The clinical characteristics present as focal seizures accompanied by dyscognitive features. Given that the MRI reveals signs of a brain tumour, the diagnosis is classified as brain tumour-related epilepsy. The brain tumour most strongly associated with epilepsy is the dys-embryoblastic neuroepithelial tumour, closely followed by low-grade astrocytoma.
Brain tumour-related epilepsy:

• Dys-embryoblastic neuroepithelial tumour: 100%
• Ganglioglioma: 80-90%
• Low-grade astrocytoma: 75%
• Meningioma: 29-60%
• Oligodendroglioma: 53%
• Anaplastic astrocytoma: 43%
• Glioblastoma multiforme: 25%
• Ependymoma: 25%
• Metastasis: 20-35%
• Primary CNS lymphoma: 10%

MRI findings of brain tumours:

• Meningioma: These appear as well-defined, smoothly contoured extra-axial masses that are adjacent to the dura. Some may exhibit calcification.
• Astrocytoma: Low-grade astrocytomas are generally hyperintense on T2-weighted images. On T1-weighted images, most low-grade astrocytomas appear hypointense compared to white matter. Contrast enhancement may be absent or mild.
• Craniopharyngioma: The lesion is located in the sellar or suprasellar region and is surrounded by calcification.
• Glioblastoma multiforme: MRI findings reveal a heterogeneous mass that typically shows low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. There are internal cystic regions, internal flow voids indicating prominent vessels, areas of high signal intensity on T1 (indicating haemorrhagic foci), neovascularisation, necrotic regions, significant peritumoral vasogenic oedema, and considerable mass effect.

• Intravenous benzodiazepines: Lorazepam, midazolam, clonazepam
• Intravenous anti-epileptics: phenytoin, valproate, or levetiracetam

• Intravenous midazolam or propofol

• Pentobarbital or Thiopentone

Hypsarrhythmia is an unusual interictal pattern, characterised by:

• High amplitude and irregular waves
• Spikes in a background of chaotic and disorganised activity

This pattern is observed on an electroencephalogram and is often found in infants diagnosed with infantile spasms.

Simple (typical) absence (petit mal) seizures are marked by a sudden halt in motor activity or speech, accompanied by a vacant expression and eyelid flickering. These seizures:

• Are rare before the age of 5
• Occur more frequently in girls
• Do not present with an aura
• Rarely last more than 30 seconds
• Are not linked to a postictal state

These characteristics help distinguish absence seizures from complex partial seizures. Children suffering from absence seizures may have numerous episodes daily, while complex partial seizures tend to occur less often. Patients maintain their muscle tone, although their heads may tilt forward slightly. Right after the seizure, individuals return to their pre-seizure activities without signs of postictal confusion. Automatic behaviours often occur during simple absence seizures. Inducing hyperventilation for 3 - 4 minutes typically triggers an absence seizure. The EEG reveals a characteristic 3 Hz spike-and-wave pattern.
Complex (atypical) absence seizures are associated with motor features, which can include:

• Myoclonic movements of the face, fingers, or limbs
• Occasional loss of body tone

These seizures produce atypical EEG spike-and-wave discharges at a rate of 2 - 2.5 Hz.

Lafora's disease arises from a defect on chromosome 6. It is inherited in an autosomal recessive manner and typically presents between the ages of 6 and 19 years.
It is characterised by:

• Brain degeneration accompanied by polyglucosan intracellular inclusion bodies.
• Fatality occurring by the age of 10 years after the onset of the disease.

Laforin is a protein that plays a role in the metabolism of glycogen.

What NOT to do during a convulsion in someone with epilepsy:

• Do not attempt to place anything in the person's mouth; there is no need for a 'tongue blade' at home or in a medical setting. This can be hazardous. Many injuries, including broken teeth and other damage, have occurred when individuals have tried to prevent 'swallowing of the tongue'. The same holds true for fingers—never insert anything into the mouth of a person who is actively convulsing.
• Do not try to restrain the convulsing limbs; instead, soften the surface, clear away obstacles and furnishings, and move the person to a safe location. Use your hands to cushion their head. Restraining the individual can cause muscle tears or the formation of a hematoma.
• If a person known to have 'convulsive' epilepsy exhibits a change in colour to blue in their face, lips, or nail beds at the onset of a seizure, count to 60. The cyanosis (bluish discolouration of lips, nails, and skin) may occur due to contracted and 'stuck' respiratory muscles during what is essentially a brief 'respiratory arrest' at the start of a convulsion. This cannot be altered by any bystander or caregiver and should resolve relatively quickly, with colour improving as the convulsion continues. If this condition persists for more than a minute, or if it is followed by relaxation (instead of convulsive movements) with ongoing bluish colour, it is advisable to assume this is a respiratory arrest and NOT a seizure. In such a case, the appropriate response would be Basic Life Support.
• Do not attempt to give the person medication or fluids while they are unresponsive; the individual should be able to converse before any attempt is made to provide anything orally.

Summary of actions to avoid during a seizure:

• Restraining the person's movements
• Putting anything in the person's mouth
• Attempting to move them unless they are in danger
• Offering them anything to eat or drink until they are fully alert
• Trying to bring them round

The likelihood of experiencing significant congenital malformations is between 4% and 5% for women taking valproate, whereas the risk in the general population ranges from 2% to 3%. The risk associated with Lamotrigine is similar to the risk of neural tube defects (N.T.D) found in the general population.

There is a strong correlation between the extent of EEG alterations, the severity of hepatic encephalopathy, and the patient's clinical condition. In cases of mild encephalopathy, characterised by slight clouding of consciousness and confusion, there is an initial slowing of the posterior dominant rhythm. This rhythm transitions from a higher to a lower alpha frequency, eventually entering the theta frequency range.
Severe encephalopathy correlates with deeper levels of coma, where the background activity primarily consists of high-amplitude, irregular delta waves. As the encephalopathy worsens, the amplitude of all activities declines below 20 µV, and the EEG may exhibit relatively low-amplitude, consistent delta activity. The most extreme abnormality observed in metabolic encephalopathy is the absence of any cerebral activity, known as electro-cerebral inactivity.

Other Important EEG patterns

• Burst suppression pattern seen: In subacute sclerosing panencephalitis: high-voltage (300-1500 pV), repetitive, polyphasic sharp and slow wave complexes of 0.5- to 2-second duration that recur every 4 - 15 seconds.
• Periodic sharp wave complexes seen: In Creutzfeldt-Jacob Disease: As the disease advances, the pattern becomes generalized and synchronous with continuous periodic stereotypic 200- to 400-millisecond sharp waves occurring at intervals of 0.5 - 1.0 seconds.
• Lambda waves: occur when reading and occasionally when watching TV. Amplitude <20 μV and duration 150 - 250 msec
• Mu waves: seen best when the cortex is exposed or if bone defects (e.g., postsurgical) are present in the skull.
• 3-Hz generalized spike and wave discharges -Childhood Absence Epilepsy.
• <3Hz (1.5 - 2.5 Hz) slow spike wave activity is seen In lennox gastaut syndrome
• Sleep spindles-Spindles are groups of waves that occur during many sleep stages but especially in stage 2 NREM.
• Saw tooth waves: REM sleep