Clinical Focus Clinical Focus

Clinical focus Clinical focus Practical neurology — 5 Recurrent unresponsive episodes and seizures Melissa A DeGruyter BM BS, BA(Physio), Janice’s story Summary Resident1 Janice, who is 23 years old, presented to her general • Careful history-taking is essential when evaluating patients with suspected epileptic seizures. It should Mark J Cook practitioner with a history of stereotyped episodes that her MB BS, MD, FRACP, partner had observed every 1–2 weeks over the previous focus on ascertaining whether the episodes are Head of Neurology,1 and seizures or a seizure mimic such as syncope. Chair of Medicine2 year. She described the episodes as starting with “butterflies in the stomach”(rising up to her throat and • Recurrent unresponsive episodes associated with lasting about 20 seconds) and intense deja vu. Her partner seizures may indicate a diagnosis of focal epilepsy 1 St Vincent’s Hospital, reported that Janice then suddenly becomes unresponsive, or complex partial epilepsy. Melbourne, VIC. has a blank look, and makes chewing movements with her Adults with a clinical diagnosis of a focal seizure 2 University of Melbourne, • Melbourne, VIC. mouth. Occasionally, she would pick at her clothes with her disorder require investigation with electroencephalo- left hand and hold her right arm in an odd fixed posture. markcook@ graphy and magnetic resonance imaging. The episodes would typically last 1–2 minutes, but it would unimelb.edu.au • The goal of treatment should be to achieve a life free be several more minutes before Janice became fully of seizures, with minimum adverse effects from responsive and she had no memory of the episodes beyond anticonvulsant medication. The choice of medication MJA 2011; 195: 586–591 the premonitory sensations. On two occasions, the should be individualised to a patient’s seizure doi: 10.5694/mja11.11260 episodes progressed to a witnessed generalised tonic– characteristics, circumstances and preferences. Dose clonic seizure of 1–2 minutes that terminated adjustments should be made according to clinical spontaneously. She was confused for several minutes response (seizure frequency and adverse effects), after both these episodes, one of which involved turning rather than on serum drug concentrations alone. of her head to the right. • Lifestyle advice, such as advice about driving Janice’s medical history was unremarkable apart from a restrictions, is important for the safety of the patient prolonged febrile seizure at 11 months of age, and results and others. of a neurological examination were nomal. Her only All anticonvulsants are potentially teratogenic. Poorly medication was the oral contraceptive pill. She worked • controlled epilepsy in pregnancy imparts significant in a clerical position. risks to the mother and baby, which need to be weighed against the risks of teratogenicity. The risk of major congenital malformations is highest with APPROACH TO THE PROBLEM valproate, particularly in high doses. Interpretation of history and examination are not a feature of primarily generalised seizures — Although the history of episodic altered awareness with patients typically have no warning of the onset of these, abnormal movements and behaviour suggests a diagnosis which rapidly engage both hemispheres of the brain.1 of focal epilepsy, other conditions must be excluded (Box Auras may provide localising information: seizures arising 1). The first step is to consider whether the episodes result from the temporal lobe result in deja vu, fear or a rising from convulsive electrical activity in the cerebral cortex, as epigastric sensation; somatosensory auras, manifesting as opposed to other causes of acute behavioural change. paraesthesia, may be reported by patients with parietal lobe Careful history-taking, including a detailed account of epilepsy; and visual auras, such as static, flashing, or the circumstances and behaviour before, during and after Previous article in this moving lights or images, are characteristic of seizures series “Dizziness on the episode, is essential. As patients almost invariably have head movement”The Medical in MJA Journal of Australia ISSN: 0025- arising from the occipital lobe. limited recall of events during a seizure, a witness account 2011;729X 195: 518–522 21 November 2011 195 10 586-591 is essential. Since epilepsy carries substantial psychosocial ©The Medical Journal of Australia 2011 Behaviour: A detailed description of behaviour during an www.mja.com.auimpact, the diagnosis should not be made unless the episode helps with diagnosis. During complex partial sei- The grading system for clinician has a high degree of certainty. recommendationsNeurology inSeries zures (also known as “focal” or “localisation-related” this article is described Aura: Rising epigastric sensations and deja vu commonly seizures), patients typically stop what they are doing in MJA 2011; 195: 328 occur in auras of seizures that have a focal onset. An aura is (behavioural arrest) and stare motionlessly for 30 seconds a “simple” partial seizure — a manifestation of epileptic to a few minutes. Another common feature of complex partial seizures is automatism — repetitive purposeless Series Editors activity confined to a small portion of the brain, without impairment of awareness or memory. Once a seizure movement, commonly involving the mouth (eg, chewing Craig S Anderson MB BS, PhD, FRACP includes brain structures that are involved in awareness motions, lip smacking) or one or both hands (eg, fidgeting, Leo Davies and memory, it is described as “complex”. Auras can occur picking at clothes). Focal seizures originate in a discrete MB BS, MD, FRACP in isolation or can precede complex partial seizures. Auras area of the brain but tend to spread rapidly over a few 586 MJA 195 (10) · 21 November 2011 Clinical focus 1 Differential diagnoses of unresponsive episodes and seizures that should be due to perinatal stroke or the stigmata of phacomatoses excluded before diagnosing focal epilepsy such as tuberous sclerosis. Recent-onset, lateralising, neu- • Syncope should always be considered when there appears to be a specific precipitant, rological abnormalities indicate the possibility of a struc- particularly pain, even if minor and considered to be irrelevant by the patient. tural brain lesion such as a cerebral neoplasm or an Precipitants may include acute pain, anxiety, rising from the supine position, coughing arteriovenous vascular malformation. and prolonged standing. There are usually one or more prodromal symptoms: nausea, lightheadedness, or tunnel or blurred vision. Onset is generally rapid, pallor and diaphoresis may be described by a witness, and brief convulsive motor activity and APPROPRIATE USE OF INVESTIGATIONS urinary incontinence are common features. The return to consciousness is usually rapid, but can be slower in older patients. Postictal confusion is not a feature, unless a significant head injury has occurred. If syncope is a diagnostic possibility, Once epileptic seizures are identified, an investigative plan electrocardiography should be performed. is required. In Janice’s case, the clear history of complex • Generalised epilepsy usually has no warning, no preceding aura and no focal features. partial events means that a focal lesion, such as a neo- Motor activity is generalised from the outset in generalised tonic–clonic seizures. plasm or scar, should be ruled out. As her symptoms were • Migraine involves progression of visual and/or sensory symptoms over a prolonged longstanding (ie, a year or more), an aggressive lesion (eg, period, typically 15–20 minutes. Visual auras are common and tend to be linear or tumour) is unlikely, but such a diagnosis should be consid- geometric. Motor activity is highly unusual. Migraine can occur without headache. ered in patients with a brief history of seizures or new Personal or family history of migraine should be sought. “fixed” neurological signs. • Psychogenic non-epileptic seizures often last longer than epileptic seizures. The eyes are often closed (sometimes this is forced); motor behaviour may be asynchronous, Electroencephalography: An electroencephalogram (EEG) with large-amplitude waxing and waning; and movements such as side-to-side rolling, should generally be performed when evaluating a patient head turning, thrashing of limbs and pelvic thrusting may be involved. Resolution of with an unprovoked seizure.4 While the results of interictal consciousness may be rapid without postictal confusion. These events occasionally EEGs are often normal, even when the diagnosis of a coexist with epileptic seizures. An underlying psychiatric illness or history of psychological distress is not always present. seizure disorder has been established, an EEG may provide • Panic attacks can occur in patients with an underlying anxiety or panic disorder. information regarding localisation and seizure type. Nor- Attacks are of variable duration, but rarely last less than 5 minutes, and are often mal EEG results do not rule out a seizure disorder, and associated with palpitations, chest pain, hyperventilation and a sense of impending some people have epileptiform abnormalities on EEG but doom. They are not associated with altered awareness. never go on to have a clinical seizure disorder. The fre- • Tics are stereotyped movements or utterances with abrupt onset and brief duration. quency of abnormalities on EEG may be increased by sleep Premonitory feelings or sensations are relieved by execution of the tic. Tics may be deprivation or provocative

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