Roughly 1 in 5 patients recommended for video-electroencephalogram (EEG) monitoring due to medically resistant or uncontrolled seizures do not have epilepsy. This means that 20% of patients receiving EEG recommendations fall into this category.
In many cases, these individuals have a differential diagnosis of something that looks like seizure activity on the outside but does not show up on an EEG or in other testing, as a typical seizure would. Some individuals will leave their appointments with diagnoses such as psychogenic non-epileptic seizures (PNES), transient ischemic attacks (TIA) or mini-strokes, fainting, migraines, attention deficit hyperactivity disorder (ADHD), movement disorders, or sleep problems.
Psychogenic Non-Epileptic Seizures (PNES): PNES is a diagnosis that individuals might get after they’ve undergone video-EEG monitoring and have had experiences that look externally like seizures, but internally there was no abnormal electrical activity noted in the brain (as seen in epileptic seizures)2. In the case of PNES, the person will not respond to typical anti-seizure medication (ASM) as the cause of the seizures is not the same as is typically treated by ASMs. PNES is typically treated with cognitive behavioral therapy, as it is widely accepted to be caused by a subconscious response to past traumas.
Transient Ischemic Attacks (TIA): According to the National Institute of Neurological Disorders and Stroke, TIA is a short period of symptoms, similar to those ones might see during a stroke. These are caused by brief blockages of blood flow to the brain3. A TIA typically only lasts a few minutes and does not cause any long-term damage. Symptoms happen suddenly and may include:
- Weakness, numbness, or paralysis in the face, arm, or leg, typically on one side of the body
- Slurred speech or trouble understanding others
- Blindness in one or both eyes or double vision
- Dizziness or loss of balance or coordination
Many of these symptoms can also be seen when individuals experience focal seizures. Many times, individuals will be misdiagnosed and sent to the epilepsy monitoring unit for monitoring. TIA’s are serious and are seen as a risk for future stroke.
Fainting (Syncope): Syncope is a symptom that can have several causes, sometimes making it difficult to diagnose the root cause. Syncope can be mistaken for seizures, as these types of spells often come on suddenly and cause a brief loss of consciousness and lack of muscle control which can lead to an increased risk of falling. According to the National Institute of Neurological Disorders and Stroke, syncope most often occurs when there is a sudden change in blood pressure, and the heart doesn’t pump enough oxygen to the brain4. This can sometimes be harmless but, if happening frequently, it may be a symptom of an underlying medical condition.
Differentiating between syncope and epilepsy may seem difficult in the moment of response. When seizures with a loss of consciousness where individuals fall occur, there are typically additional symptoms present (such as shallow breathing and shaking or jerking movements in the limbs). Whereas, in the case of syncope, individuals usually lose consciousness and fall for brief periods with no additional symptoms, but brief twitching can be seen.
Migraines: According to the National Institute of Neurological Disorders and Stroke, a migraine is a type of headache characterized by recurrent attacks of moderate to severe throbbing and pulsating pain on one side of the head. Migraines can last from 4 to 72 hours (about 3 days), and other symptoms might include increased sensitivity to light, noise and odors, nausea, and vomiting. Occasionally, migraines can exist with an aura which includes visual disturbances and other neurological symptoms that appear about 10 to 60 minutes before the actual headache and last more than an hour5. Classic symptoms might include:
- Trouble speaking
- Abnormal sensations such as:
- Numbness
- Muscle weakness on one side of the body
- A tingling sensation in the hands or face
- Confusion
- Nausea
- Loss of appetite
- Increased sensitivity to light, sound, or noises
- Blurred vision
- Mood changes
- Fatigue
Many of the migraine symptoms listed above are also seen when some individuals experience focal seizures. However, migraines differ from focal seizures typically in length (migraines last much longer than most seizures) and focal seizures typically do not initially present with head pain.
Attention Deficit Hyperactivity Disorder (ADHD): According to the National Institute of Mental Health, ADHD is marked by an ongoing pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. People with a diagnosis of ADHD may have difficulty staying on task, sustaining focus, and staying organized. They may also move about constantly, fidgeting, tapping, or talking out of turn6.
In many cases, the inability to focus as seen in ADHD may happen randomly where an individual has a blank dazed stare and loses track of the conversation or information being presented to them. These spans of inattention may be hard to break, and in some cases can look like absence seizures.
Movement Disorders: For the purpose of this educational blog, we will focus specifically on Tourette Syndrome as a selected movement disorder, however, it is possible for other movement disorders such as Parkinson’s Disease, conditions causing atrophy, and some palsy diagnoses to be misdiagnosed as seizures. According to the National Institute of Neurological Disorders and Stroke, Tourette syndrome is a neurological disorder that may cause sudden unwanted, and uncontrolled rapid and repeated movements or vocal sounds called tics7.
People who experience tics might be misdiagnosed with epilepsy, as many tics can cause motor symptoms that might be seen in multiple seizure types. Symptoms such as eye blinking, shoulder shrugging, head or shoulder jerking, or vocal tics like barking, or laughing can be seen as well. It is possible for people to have both Tourette syndrome as well as epilepsy8, making it tough to distinguish symptoms.
Sleep problems: Parasomnias, which are a group of sleep disorders defined as undesirable physical events or experiences that occur during the initiation of sleep, during sleep, or arousal from sleep9. Parasomnia is something that occasionally may be misdiagnosed as seizures. These sleep disorders might manifest as sleepwalking, sleep terrors, sleep talking, and sleep paralysis.
Partners or parents of individuals who experience parasomnia-related movements or vocalizations may be concerned that the individual is experiencing seizures. Many individuals who experience parasomnia have a blank dazed stare during episodes and are unresponsive to any external stimuli. Sleep disorders are much more common in the younger demographic, however, REM sleep disturbances caused by other conditions may occur later in life9.
It is important to note that seizures can exist alongside many other conditions and that any of the above-listed conditions or diagnoses can be something an individual experiences as well as seizures, was misdiagnosed with, or has been diagnosed with seizures instead of the proper condition. It is incredibly important that all conditions are properly diagnosed and treated in a timely manner, and getting the correct diagnoses initially leads to much better treatment outcomes in most cases.
If you are concerned that you or a family member has been misdiagnosed, please speak with your doctor. The information, including text, graphics, images, and other material on this website and provided by the Epilepsy Foundation of Northeastern New York, is for informational purposes only. No material on this site is intended to be a substitute for professional medical advice, diagnosis, or treatment.
If you are interested in learning more about seizure recognition and first aid, please reach out to our team by calling (518) 456-7501 or visiting our website for additional resources.
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