Each Tech Tips article focuses on a special topic and is written by ASET members who are a subject-matter expert on a given topic in Neurodiagnostics. This Issue’s article focuses on working in an Epilepsy Monitoring Unit (EMU) with PNES patients.
Working in an Epilepsy Monitoring Unit (EMU) brings many opportunities to perform Video EEGs (VEEGs) on unusual or unique patients. Most techs have distinct memories about many of the patients they have worked with, especially those patients who presented with an interesting history or had unusual EEG findings. Often these memories lead to excellent extemporaneous tech educational sessions. The patient with psychogenic non-epileptic seizures (PNES) can and should be a topic worthy of such discussions.
Data indicate that approximately 20–30% of admissions to an EMU can consist of patients with a known or suspected diagnosis of PNES, so it is highly likely that every EMU tech will eventually set up and monitor such a patient1. While we should treat all of our patients with dignity and respect, it is especially important to do so with this type of patient. Some background into the disorder highlights common denominators for patients with PNES: the majority are female, their events started in their teens to twenties, a significant percentage of patients have some type of psychiatric or unexplained medical disorder such as fibromyalgia/asthma/gastroesophageal reflux or headaches, and there is usually a history of some type of emotional or physical abuse2, 5, 7. Additionally, 10–30% of patients with PNES can also have a diagnosis of true epileptic seizures5, 7, further complicating diagnosis and treatment. Many of these patients have been or are currently taking more than one antiepileptic drug (AED), but they continue to have multiple events5, 7.
There are some characteristics that tend to occur more frequently or even exclusively in patients with PNES. The frequency of events in PNES is usually greater than those of patients with epilepsy5. Being in a stressful situation, or undergoing routine Photic Stimulation (PS) and Hyperventilation (HV) during an EEG is more likely to trigger an event of PNES5. Technologists should be aware of these precipitating factors, and plan accordingly.
Differentiating a PNES event from an epileptic event based solely on clinical information is very difficult. By description, it is easy to confuse a PNES event with a generalized tonic-clonic or frontal lobe seizure5, 7. Although a typical PNES event often consists of asynchronous thrashing movements or periods of unresponsiveness with an EEG that shows no correlating abnormalities, by the description the patient is having shaking of extremities or staring. Similar descriptions can be applied to tonic-clonic or absence seizures. Therefore, the differential diagnosis of PNES will often depend on the actions of the EEG technologist when these events occur.
If a patient is having a PNES event which consists of motor activity, it is important to observe the sequence of events which occur. A typical true generalized tonic-clonic seizure will start with a period of stiffness, progressing to a period of strong, rhythmic, synchronous clonic activity which gradually lessens in intensity and frequency. The duration is usually less than 3 minutes and there can be other clinical signs such as cyanosis or incontinence that are difficult or impossible to voluntarily perform. Comparatively, a PNES event will often consist of arrhythmic, asynchronous movements that will wax and wane in both intensity and frequency. The patient may close their eyes during the event and/or move their head from side to side5. These events can last for long periods of time, and when completed, the patient is completely responsive7 with no post ictal fatigue or confusion. Patients with PNES may coherently answer questions and obey commands during the event5, whereas patients with tonic clonic or absence seizures are unable to respond to questions or commands. If the PNES event is one of unresponsiveness, it is important to stimulate the patient to demonstrate responsiveness. Holding the patient’s arm above their face or head and letting the arm fall is a good indication of whether the patient is aware of their surroundings. A patient with PNES will usually let their arm fall to the side, avoiding their hand striking their face7. If the patient’s eyes are open during the event, look for voluntary fixation of their gaze by holding a mirror in front of the patient. If the eyes fixate on their reflection this is an indication of voluntary eye control7.
What circumstances contribute to a patient developing PNES? Many authors feel that these patients have not developed adequate coping skills to deal with stress or adverse events1, 5, 6, 7. Patients all over the world, regardless of culture, are affected by PNES5. PNES is usually considered a type of somatoform disorder called a conversion disorder. This means that the patient shows clinical symptoms that resemble a physical disorder but does not have corroborating physical findings. A conversion disorder is a type of somatoform disorder in which these clinical findings have a psychologic rather than physical origin4. Many PNES patients have also been diagnosed with anxiety, depression, borderline personality disorders or post-traumatic stress disorder (PTSD)6.
Psychogenic symptoms (symptoms that are perceived as real but don’t have an organic cause) can take multiple forms, including vomiting, diarrhea, stomach pain, non-cardiac chest pain, shortness of breath, etc.3. These findings could be diagnosed, based on a description of the symptoms, as irritable bowel syndrome, heart disease or asthma. But what if there are no substantiating physical findings? No cardiac issues, no lung inflammation, no findings on endoscopy or colonoscopy? Are the symptoms any less real to the patient? Absolutely not! Apply this thought process to the patient with PNES. Although the EEG is normal during the event, with no evidence of epileptic abnormalities, to the patient their symptoms (the event) are real. Remember, if you haven’t experienced it firsthand, it is impossible to judge how another person responds to a significant event.
What does this mean for us as EEG techs? First of all, compassion is required and judgment should be suspended. The patient should be treated with respect and dignity. It is important to realize that these patients are not “faking it”. While there are indeed some patients who find any diagnosis of illness to have advantages such as receiving extra attention, or avoiding social and societal responsibilities7, the majority of patients with PNES sincerely want to “be cured”. They are individuals who have most likely already suffered a severe emotional or physical trauma. Many of these patients have willingly complied with an unhelpful AED regime (some for many years)7. These patients continue to seek medical help, going from physician to physician; hospital to hospital. They find their symptoms to be physically and socially debilitating. They deserve our help and our compassion, not our judgment and dismissal.
VEEG is the procedure most often credited with diagnosing a patient with PNES. During the event, the EEG will not show any of the changes associated with a true epileptic seizure (spikes, sharp waves, spike, and waves). Often, the EEG is obscured with muscle or movement artifact. Utilizing the midline electrodes (Fz, Cz, Pz) can usually provide good information regarding the level of consciousness and the presence or absence of epileptiform activity. The emergence of a normal background rhythm at the end of the event argues against a true epileptic seizure.
Some patients with PNES will state that their events occur only in sleep. VEEG can accurately display the patient’s state of consciousness at the onset of the event. Frontal lobe seizures usually arise directly from sleep, whereas patients who are experiencing a PNES event will show arousal and a portion of waking background before the event begins (7).
Performing activation procedures such as HV and PS are acceptable methods for inducing an event of PNES5. Additionally, sometimes simply explaining to the patient that it is important to achieve a correct diagnosis so that appropriate treatment can be instituted and un-needed and potentially harmful medications can be eliminated or adjusted, is all that is needed to provoke a typical event. Regardless of which method is used, it is important that the tech be completely honest with the patient at all times. It is never acceptable to “lead a patient on” with false comments about the EEG findings, for example: “Your EEG is looking like you’re about to have an event…”, or “Your EEG is showing some funny activity so I think you should be getting ready to have your spell”. Remember, a percentage of PNES patients actually have a diagnosis of epilepsy, so their interictal EEG may actually be abnormal. Only the findings of the ictal EEG during the typical event are diagnostic. Many patients will actually have their PNES event within the first few hours of VEEG5. Once an event is recorded, it is important to verify that the event is representative of the patient’s typical spell5. If the patient has more than one type of spell, try to capture each type during the VEEG.
Patients with simple partial seizures have been known to have normal EEGs during their seizures. Likewise, patients with frontal lobe epilepsy often have normal waking EEGs. And, patients with a true diagnosis of epilepsy have normal interictal routine EEGs up to 30% of the time7. It is essential that both the VEEG findings as well as the clinical event be utilized equally to provide a correct diagnosis of PNES5.
So, what happens after the EEG technologist has done their job and successfully recorded a typical PNES event? First of all, the patient must be told their “new” diagnosis. The process for doing this varies widely and often comes down to how comfortable a neurologist is at explaining this change in diagnosis and treatment. Unfortunately, the average length of time between PNES onset and PNES diagnosis is 5–7 years 2, 6. Obviously, it would be very difficult for a patient who has spent years feeling as if their events were a medical condition to suddenly be told their problems are psychiatric. The patient’s care will usually be transferred from the Neurology service to the Psychiatry service. If both the neurologist and the psychiatrist can be present during this initial informational meeting with the patient, the patient will have more confidence that their transfer of care will be seamless6.
Describing the patient’s events and noting that there are no corroborating EEG abnormalities is usually the first step in discussing the diagnosis of PNES with a patient6, 7. Much reassurance is given to the patient that they are not “crazy”, and that their experiences, while not epileptic, are most certainly real6, 7. The physician can then explain the relationship between stress and PNES6, 7. Understanding the underlying cause of their PNES events is difficult for most patients1. One study utilizes the example of “switching off” your brain, for example when driving home but not remembering the trip, or the way a child who is being repeatedly abused may “switch off” or dissociate their brain during their abuse, as a way of explaining why the patient may not understand what their “trigger” is for precipitating PNES events7. The need for tapering AEDs is explained to the patient6, 7. Finally, a psychiatric treatment plan is drawn up, and the need for compliance in following the plan is stressed6, 7. Usually the patient is referred for some type of cognitive behavioral therapy, although group therapy, antidepressants, hypnotherapy, and eye movement desensitization and reprocessing have also been used with varying degrees of success6.
How does the patient cope with this new information? PNES patients need a great deal of time to process and understand this change to their self-image, and much support to ensure that they continue to maintain a good level of trust with their healthcare provider1. Patients can feel as if the responsibility for the resolution of their problems had been shifted to them, rather than being the responsibility of the health care professional 1. Helping them understand what precipitates their events, and having the health care professional take them seriously were the two most important factors identified by PNES patients as a requirement to get them started on the road to recovery1.
Unfortunately, a large percentage of patients who receive a diagnosis of PNES have a poor outcome. Some studies relate this to the delay between PNES onset and PNES diagnosis, stating that the longer the delay the less effective the treatment7. Some patients may simply have a difficult time accepting a psychiatric diagnosis over a medical one. Regardless, this patient population represents a challenge to the EEG technologist as well as the neurologist and psychiatrist. Creating a safe and compassionate environment is the single best thing the EEG technologist can do for the patient with PNES. After that, it is up to the physicians, and the patient, to understand and hopefully conquer this difficult condition.
This article was written by Pat Lordeon, R. EEG T., FASET.
- Karterud HN, Knizek BL, Nakken KO. Changing the diagnosis from epilepsy to PNES: Patients’ experiences and understanding of their new diagnosis. Seizure 19 (2010) 40-46. doi:10.1016/j.seizure.2009.11.001.
- Dixit R, Popescu A, Bagic A, Ghearing G, Hendrickson R. Medical comorbidities in patients with psychogenic nonepileptic spells (PNES) referred for video-EEG monitoring. Epilepsy & Behavior 28 (2013) 137-140. http://dx.doi.org/10.1016/j.yebeh.2013.05.004.
- Benbadis SR, Lutsep HL et al. Psychogenic Nonepileptic Seizures. https://emedicine.medscape.com/article/1184694-overview.
- The Truth about Psychogenic Nonepileptic Seizures. https://www.epilepsy.com/article/2014/3/truth-about-psychogenic-nonepileptic-seizures. Epilepsy Foundation.
- LaFrance WC, Baker GA, Duncan R, Goldstein LH, Reuber M. Minimum requirements for the diagnosis of psychogenic nonepileptic seizures: A staged approach. Epilepsia 54(11):2005-2018, 2013. doi: 10.1111/epi.12356.
- Baslet G. Psychogenic nonepileptic seizures: a treatment review. What have we learned since the beginning of the millennium? Neuropsychiatr Dis Treat. 2012; 8: 585-598. doi: 2147/NDT.S3230 https://www.ncib.nlm.nih.gov/pmc.articles/PMC3523560/.
- Mellers JDC. The approach to patients with “non-epileptic seizures” Postgrad Med J 2005;81:498-504. doi: 1136/pgmj.2004.029785.