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Focal seizure

Focal seizures (also called partial seizures[1] and localized seizures) are seizures which affect initially only one hemisphere of the brain.[2][3] The brain is divided into two hemispheres, each consisting of four lobes – the frontal, temporal, parietal and occipital lobes. A focal seizure is generated in and affects just one part of the brain – a whole hemisphere or part of a lobe. Symptoms will vary according to where the seizure occurs. When seizures occur in the frontal lobe the patient may experience a wave-like sensation in the head. When seizures occur in the temporal lobe, a feeling of déjà vu may be experienced. When seizures are localized to the parietal lobe, a numbness or tingling may occur. With seizures occurring in the occipital lobe, visual disturbances or hallucinations have been reported.[4]

Focal seizure
Other namesPartial seizures, localized seizures
SpecialtyNeurology 

Types edit

As of 2017, focal seizures are split into two main categories, focal onset aware, and focal onset impaired awareness.[5][6] What was previously termed a secondary generalised seizure is now termed a focal to bilateral seizure.[6]

In focal onset aware seizures, a small part of one of the lobes may be affected and the person remains conscious. This can often be a precursor to a larger focal onset impaired awareness seizure. When this is the case, the focal aware seizure is usually called an aura.

A focal impaired awareness seizure affects a larger part of the hemisphere and the person may lose consciousness.

If a focal seizure spreads from one hemisphere to the other side of the brain, this will give rise to a focal to bilateral seizure.[5][6] The person will become unconscious and may experience a tonic–clonic seizure. When people have multiple focal seizures they generally have a condition known as temporal lobe epilepsy. (A generalized seizure is one that involves both sides of the brain from the onset.)[6]

Simple partial seizures edit

Simple partial seizures are seizures which affect only a small region of the brain, often the temporal lobes or structures found there, such as the hippocampi. People who have focal aware seizures remain conscious.[7] Focal aware seizures often precede larger focal impaired awareness seizures, where the abnormal electrical activity spreads to a larger area of the brain. This can result in a tonic-clonic seizure.[8]

Presentation edit

Simple partial seizures are a very subjective experience, and the symptoms vary greatly between people. Since symptoms can be subtle, diagnosis can be delayed by months or years.[9] The symptoms of these seizures can also be misconstrued as auras, especially for epilepsy patients with multiple types of seizure diagnosis. This is due to the varying locations of the brain in which the seizures originate (e.g., Rolandic). A simple partial seizure may go unnoticed by others or shrugged off by the patient as merely a "funny turn." Focal aware seizures usually start suddenly and are very brief, typically lasting 60 to 120 seconds.[10][failed verification]

Some common symptoms of a simple partial seizure, when the person is awake, are:[7][failed verification]

  • preserved consciousness
  • sudden and inexplicable feelings of fear, anger, sadness, happiness or nausea
  • sensations of falling or movement
  • experiencing of unusual feelings or sensations
  • altered sense of hearing, smelling, tasting, seeing, and tactile perception (sensory illusions or hallucinations), or feeling as though the environment is not real (derealization) or dissociation from the environment or self (depersonalization)
  • a sense of spatial distortion—things close by may appear to be at a distance
  • déjà vu (familiarity) or jamais vu (unfamiliarity)
  • laboured speech or inability to speak at all
  • usually the event is remembered in detail

When a seizure occurs during sleep, the person will often become semi-conscious and act out a dream they were having while engaging with the real environment as normal. Objects and people usually appear normal or only slightly distorted to them, and will be able to communicate with them on an otherwise normal level. However, since the person is still acting in a dream-like state, they will assimilate any hallucinations or delusions into their communication, often speaking to a hallucinatory person or speaking of events or thoughts pertaining to their dream or a hallucination.

While-asleep symptoms include:

  • onset usually in REM sleep
  • dream-like state
  • appearance of full consciousness
  • hallucinations or delusions
  • behavior or visions typical in dreams
  • ability to engage with the environment and other people as in full consciousness, though often behaving abnormally, erratically, or failing to be coherent
  • complete amnesia or assimilating the memory as though it was a normal dream on regaining full consciousness
  • dreams of daily life that appear as if they happened in reality, and can cause disorientation upon awakening

Although hallucinations may occur during focal aware seizures they are differentiated from psychotic symptoms by the fact that the person is usually aware that the hallucinations are not real.[10]: 17 

Jacksonian march edit

Jacksonian march or Jacksonian seizure is a phenomenon where a simple partial seizure spreads from the distal part of the limb toward the ipsilateral face (on same side of body). They involve a progression of the location of the seizure in the brain, which leads to a "march" of the motor presentation of symptoms.[11][citation needed]

Jacksonian seizures are initiated with abnormal electrical activity within the primary motor cortex. They are unique in that they travel through the primary motor cortex in succession, affecting the corresponding muscles, often beginning with the fingers. This is felt as a tingling sensation, or a feeling of waves through the fingers when touched together. It then affects the hand and moves on to more proximal areas on the same side of body. Symptoms often associated with a Jacksonian seizure are sudden head and eye movements, tingling, numbness, smacking of the lips, and sudden muscle contractions. Most of the time any one of these actions can be seen as normal movements, without being associated with the seizure occurring.[citation needed] They occur at no particular moment and last only briefly. They may result in secondary generalized seizure involving both hemispheres. They can also start at the feet, manifesting as tingling or pins and needles, and there are painful cramps in the foot muscles, due to the signals from the brain. Because it is a partial seizure, the postictal state is of normal consciousness.[citation needed] Jacksonian seizures are named after their discoverer, John Hughlings Jackson, an English neurologist, whose studies led to the discovery of the seizures' initiation point (in the primary motor cortex) in 1863.[12]

Complex partial seizures edit

A complex partial seizure is a seizure that is associated with unilateral cerebral hemisphere involvement and causes impairment of awareness or responsiveness, i.e. alteration of consciousness.[13][6]

Presentation edit

Complex partial seizures are often preceded by an aura.[14] The seizure aura is a focal aware seizure.[14] The aura may manifest itself as a feeling of déjà vu, jamais vu, fear, euphoria or depersonalization.[15][better source needed] The aura might also occur as a visual disturbance, such as tunnel vision or a change in the perceived size of objects.[16] Once consciousness is impaired, the person may display automatisms, such as lip smacking, chewing or swallowing.[15] There may also be loss of memory (amnesia) surrounding the seizural event.[14] The person may still be able to perform routine tasks such as walking, although such movements are not purposeful or planned. Witnesses may not recognize that anything is wrong. The person may or may not even realize that they experienced a seizure.

Complex partial seizures might arise from any lobe of the brain.[14] They most commonly arise from the mesial temporal lobe, particularly the amygdala, hippocampus, and neocortical regions.[17] A common associated brain abnormality is mesial temporal sclerosis.[15] Mesial temporal sclerosis is a specific pattern of hippocampal neuronal loss accompanied by hippocampal gliosis and atrophy.[18] Complex partial seizures occur when excessive and synchronous electrical brain activity causes the impaired awareness and responsiveness.[19] The abnormal electrical activity might spread to the rest of the brain and cause a focal to bilateral seizure or a generalized tonic–clonic seizure.[20] The newer classification of 2017 groups only focal and generalized seizures, and generalized seizures are those that involve both sides of the brain from the onset.[6][5]

Treatment edit

Most people with focal seizures due to epilepsy require medications to manage the condition. Not all people with epilepsy find that the medications given are effective at preventing seizures and approximately 30% of people cannot keep their seizures in remission.[21] A newer pharmaceutical approach using immunomodulator drugs in addition to standard medication treatments has been suggested and there is some evidence that this approach may reduce the frequency of focal seizures.[21] It is not clear if this medicine is well tolerated in adults and children.[21]

References edit

  1. ^ "Partial (Focal) Seizures". Johns Hopkins Medicine. The Johns Hopkins University. Retrieved 1 September 2016.
  2. ^ Bradley, Walter G. (2012). "67". Bradley's neurology in clinical practice (6th ed.). Philadelphia, PA: Elsevier/Saunders. ISBN 978-1437704341.
  3. ^ "at Dorland's Medical Dictionary
  4. ^ [1] 2013-08-09 at the Wayback Machine, Epilepsy Society - Are all seizures the same.
  5. ^ a b c "2017 Revised Classification of Seizures". Epilepsy Foundation.
  6. ^ a b c d e f "Types of Seizures". Epilepsy Foundation.
  7. ^ a b Steven C. Schachter, MD; Joseph I. Sirven, MD (July 2013). "Simple Focal Seizures". Epilepsy Foundation. Retrieved 31 August 2016.
  8. ^ Amit M. Shelat (27 February 2016). "Partial (focal) seizure". MedlinePlus. Retrieved 31 August 2016.
  9. ^ Pellinen, Jacob; Tafuro, Erica; Yang, Annie; Price, Dana; Friedman, Daniel; Holmes, Manisha; Barnard, Sarah; Detyniecki, Kamil; Hegde, Manu; Hixson, John; Haut, Sheryl (2020). "Focal nonmotor versus motor seizures: The impact on diagnostic delay in focal epilepsy". Epilepsia. 61 (12): 2643–2652. doi:10.1111/epi.16707. ISSN 1528-1167. PMID 33078409. S2CID 224811014.
  10. ^ a b Hart, YM (2007). Epilepsy Questions and Answers. Merit Publishing. ISBN 978-1873413876.
  11. ^ "Dorlands Medical Dictionary:jacksonian epilepsy".[permanent dead link]
  12. ^ synd/3332 at Who Named It?
  13. ^ Trescher, William H., and Ronald P. Lescher 2000, p. 1748.
  14. ^ a b c d Trescher, William H., and Ronald P. Lescher 2000, p. 1749.
  15. ^ a b c Murro, Anthony M. 2006.
  16. ^ Engelsen, B A., C Tzoulis, B Karlsen, A Lillebø, L M 2008.
  17. ^ Trescher, William H., and Ronald P. Lescher 2000, p. 1750.
  18. ^ Trepeta, Scott 2007.
  19. ^ "International League Against Epilepsy." 2008.
  20. ^ Trescher, William H., and Ronald P. Lescher 2000, p. 1747.
  21. ^ a b c Panebianco, Mariangela; Walker, Lauren; Marson, Anthony G (2023-10-16). Cochrane Epilepsy Group (ed.). "Immunomodulatory interventions for focal epilepsy". Cochrane Database of Systematic Reviews. 2023 (10). doi:10.1002/14651858.CD009945.pub3.

External links edit

focal, seizure, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, scholar, jstor, february, 2. This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Focal seizure news newspapers books scholar JSTOR February 2013 Learn how and when to remove this template message Focal seizures also called partial seizures 1 and localized seizures are seizures which affect initially only one hemisphere of the brain 2 3 The brain is divided into two hemispheres each consisting of four lobes the frontal temporal parietal and occipital lobes A focal seizure is generated in and affects just one part of the brain a whole hemisphere or part of a lobe Symptoms will vary according to where the seizure occurs When seizures occur in the frontal lobe the patient may experience a wave like sensation in the head When seizures occur in the temporal lobe a feeling of deja vu may be experienced When seizures are localized to the parietal lobe a numbness or tingling may occur With seizures occurring in the occipital lobe visual disturbances or hallucinations have been reported 4 Focal seizureOther namesPartial seizures localized seizuresSpecialtyNeurology Contents 1 Types 1 1 Simple partial seizures 1 1 1 Presentation 1 1 2 Jacksonian march 1 2 Complex partial seizures 1 2 1 Presentation 2 Treatment 3 References 4 External linksTypes editAs of 2017 focal seizures are split into two main categories focal onset aware and focal onset impaired awareness 5 6 What was previously termed a secondary generalised seizure is now termed a focal to bilateral seizure 6 In focal onset aware seizures a small part of one of the lobes may be affected and the person remains conscious This can often be a precursor to a larger focal onset impaired awareness seizure When this is the case the focal aware seizure is usually called an aura A focal impaired awareness seizure affects a larger part of the hemisphere and the person may lose consciousness If a focal seizure spreads from one hemisphere to the other side of the brain this will give rise to a focal to bilateral seizure 5 6 The person will become unconscious and may experience a tonic clonic seizure When people have multiple focal seizures they generally have a condition known as temporal lobe epilepsy A generalized seizure is one that involves both sides of the brain from the onset 6 Simple partial seizures edit Simple partial seizures are seizures which affect only a small region of the brain often the temporal lobes or structures found there such as the hippocampi People who have focal aware seizures remain conscious 7 Focal aware seizures often precede larger focal impaired awareness seizures where the abnormal electrical activity spreads to a larger area of the brain This can result in a tonic clonic seizure 8 Presentation edit Simple partial seizures are a very subjective experience and the symptoms vary greatly between people Since symptoms can be subtle diagnosis can be delayed by months or years 9 The symptoms of these seizures can also be misconstrued as auras especially for epilepsy patients with multiple types of seizure diagnosis This is due to the varying locations of the brain in which the seizures originate e g Rolandic A simple partial seizure may go unnoticed by others or shrugged off by the patient as merely a funny turn Focal aware seizures usually start suddenly and are very brief typically lasting 60 to 120 seconds 10 failed verification Some common symptoms of a simple partial seizure when the person is awake are 7 failed verification preserved consciousness sudden and inexplicable feelings of fear anger sadness happiness or nausea sensations of falling or movement experiencing of unusual feelings or sensations altered sense of hearing smelling tasting seeing and tactile perception sensory illusions or hallucinations or feeling as though the environment is not real derealization or dissociation from the environment or self depersonalization a sense of spatial distortion things close by may appear to be at a distance deja vu familiarity or jamais vu unfamiliarity laboured speech or inability to speak at all usually the event is remembered in detailWhen a seizure occurs during sleep the person will often become semi conscious and act out a dream they were having while engaging with the real environment as normal Objects and people usually appear normal or only slightly distorted to them and will be able to communicate with them on an otherwise normal level However since the person is still acting in a dream like state they will assimilate any hallucinations or delusions into their communication often speaking to a hallucinatory person or speaking of events or thoughts pertaining to their dream or a hallucination While asleep symptoms include onset usually in REM sleep dream like state appearance of full consciousness hallucinations or delusions behavior or visions typical in dreams ability to engage with the environment and other people as in full consciousness though often behaving abnormally erratically or failing to be coherent complete amnesia or assimilating the memory as though it was a normal dream on regaining full consciousness dreams of daily life that appear as if they happened in reality and can cause disorientation upon awakeningAlthough hallucinations may occur during focal aware seizures they are differentiated from psychotic symptoms by the fact that the person is usually aware that the hallucinations are not real 10 17 Jacksonian march edit Jacksonian march or Jacksonian seizure is a phenomenon where a simple partial seizure spreads from the distal part of the limb toward the ipsilateral face on same side of body They involve a progression of the location of the seizure in the brain which leads to a march of the motor presentation of symptoms 11 citation needed Jacksonian seizures are initiated with abnormal electrical activity within the primary motor cortex They are unique in that they travel through the primary motor cortex in succession affecting the corresponding muscles often beginning with the fingers This is felt as a tingling sensation or a feeling of waves through the fingers when touched together It then affects the hand and moves on to more proximal areas on the same side of body Symptoms often associated with a Jacksonian seizure are sudden head and eye movements tingling numbness smacking of the lips and sudden muscle contractions Most of the time any one of these actions can be seen as normal movements without being associated with the seizure occurring citation needed They occur at no particular moment and last only briefly They may result in secondary generalized seizure involving both hemispheres They can also start at the feet manifesting as tingling or pins and needles and there are painful cramps in the foot muscles due to the signals from the brain Because it is a partial seizure the postictal state is of normal consciousness citation needed Jacksonian seizures are named after their discoverer John Hughlings Jackson an English neurologist whose studies led to the discovery of the seizures initiation point in the primary motor cortex in 1863 12 Complex partial seizures edit A complex partial seizure is a seizure that is associated with unilateral cerebral hemisphere involvement and causes impairment of awareness or responsiveness i e alteration of consciousness 13 6 Presentation edit Complex partial seizures are often preceded by an aura 14 The seizure aura is a focal aware seizure 14 The aura may manifest itself as a feeling of deja vu jamais vu fear euphoria or depersonalization 15 better source needed The aura might also occur as a visual disturbance such as tunnel vision or a change in the perceived size of objects 16 Once consciousness is impaired the person may display automatisms such as lip smacking chewing or swallowing 15 There may also be loss of memory amnesia surrounding the seizural event 14 The person may still be able to perform routine tasks such as walking although such movements are not purposeful or planned Witnesses may not recognize that anything is wrong The person may or may not even realize that they experienced a seizure Complex partial seizures might arise from any lobe of the brain 14 They most commonly arise from the mesial temporal lobe particularly the amygdala hippocampus and neocortical regions 17 A common associated brain abnormality is mesial temporal sclerosis 15 Mesial temporal sclerosis is a specific pattern of hippocampal neuronal loss accompanied by hippocampal gliosis and atrophy 18 Complex partial seizures occur when excessive and synchronous electrical brain activity causes the impaired awareness and responsiveness 19 The abnormal electrical activity might spread to the rest of the brain and cause a focal to bilateral seizure or a generalized tonic clonic seizure 20 The newer classification of 2017 groups only focal and generalized seizures and generalized seizures are those that involve both sides of the brain from the onset 6 5 Treatment editMost people with focal seizures due to epilepsy require medications to manage the condition Not all people with epilepsy find that the medications given are effective at preventing seizures and approximately 30 of people cannot keep their seizures in remission 21 A newer pharmaceutical approach using immunomodulator drugs in addition to standard medication treatments has been suggested and there is some evidence that this approach may reduce the frequency of focal seizures 21 It is not clear if this medicine is well tolerated in adults and children 21 References edit Partial Focal Seizures Johns Hopkins Medicine The Johns Hopkins University Retrieved 1 September 2016 Bradley Walter G 2012 67 Bradley s neurology in clinical practice 6th ed Philadelphia PA Elsevier Saunders ISBN 978 1437704341 partial seizure at Dorland s Medical Dictionary 1 Archived 2013 08 09 at the Wayback Machine Epilepsy Society Are all seizures the same a b c 2017 Revised Classification of Seizures Epilepsy Foundation a b c d e f Types of Seizures Epilepsy Foundation a b Steven C Schachter MD Joseph I Sirven MD July 2013 Simple Focal Seizures Epilepsy Foundation Retrieved 31 August 2016 Amit M Shelat 27 February 2016 Partial focal seizure MedlinePlus Retrieved 31 August 2016 Pellinen Jacob Tafuro Erica Yang Annie Price Dana Friedman Daniel Holmes Manisha Barnard Sarah Detyniecki Kamil Hegde Manu Hixson John Haut Sheryl 2020 Focal nonmotor versus motor seizures The impact on diagnostic delay in focal epilepsy Epilepsia 61 12 2643 2652 doi 10 1111 epi 16707 ISSN 1528 1167 PMID 33078409 S2CID 224811014 a b Hart YM 2007 Epilepsy Questions and Answers Merit Publishing ISBN 978 1873413876 Dorlands Medical Dictionary jacksonian epilepsy permanent dead link synd 3332 at Who Named It Trescher William H and Ronald P Lescher 2000 p 1748 a b c d Trescher William H and Ronald P Lescher 2000 p 1749 a b c Murro Anthony M 2006 Engelsen B A C Tzoulis B Karlsen A Lillebo L M 2008 Trescher William H and Ronald P Lescher 2000 p 1750 Trepeta Scott 2007 International League Against Epilepsy 2008 Trescher William H and Ronald P Lescher 2000 p 1747 a b c Panebianco Mariangela Walker Lauren Marson Anthony G 2023 10 16 Cochrane Epilepsy Group ed Immunomodulatory interventions for focal epilepsy Cochrane Database of Systematic Reviews 2023 10 doi 10 1002 14651858 CD009945 pub3 External links edit Retrieved from https en wikipedia org w index php title Focal seizure amp oldid 1180497609, wikipedia, wiki, book, books, library,

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