Indian Epilepsy Society
http://www.epilepsyindia.org/indianepilepsysociety/index.htm
Tuesday, September 23, 2008
International League Against Epilepsy (ILAE)
The International League Against Epilepsy (ILAE) is the world’s preeminent association of physicians and other health professionals working towards a world where no persons' life is limited by Epilepsy. Its mission is to provide the highest quality of care and well-being for those afflicted with the condition and other related seizure disorders.
The League aims:
To advance and disseminate knowledge about epilepsy
To promote research, education and training
To improve services and care for patients, especially by prevention, diagnosis and treatment
The League aims:
To advance and disseminate knowledge about epilepsy
To promote research, education and training
To improve services and care for patients, especially by prevention, diagnosis and treatment
Monday, September 22, 2008
Inheritance of reading epilepsy
Primary reading epilepsy was diagnosed by special electroencephalo- graphic (EEG) studies in an adolescent youth after his first grand mal seizure. Similar studies of members in three generations of his family showed primary reading epilepsy in his first cousin and in two of his siblings. The disorder in the siblings had not been noticed by parents or teachers and probably would have remained undetected without the use of special techniques. This pedigree buttresses other reported evidence for autosomal dominant transmission of reading epilepsy. The centrencephalic EEG trait also is present in some members of this family. The possible implications of this association are discussed.
Inheritance of reading epilepsy
RICHARD F. DALY, M.D. and FRANCIS M. FORSTER, M.D.
Department of Neurology, University of Wisconsin Center for Health Sciences, Madison, Wisconsin.
NEUROLOGY 1975;25:1051
Inheritance of reading epilepsy
RICHARD F. DALY, M.D. and FRANCIS M. FORSTER, M.D.
Department of Neurology, University of Wisconsin Center for Health Sciences, Madison, Wisconsin.
NEUROLOGY 1975;25:1051
Reading Epilepsy
For a long time it has been known that seizures could
be evoked in certain epileptic individuals by a discrete
physiologic or psychologic stimulus. The term reflex
epilepsy is reserved for this small subgroup. Forster(1)
has classified these seizures in accordance with their
evocative stimuli into five types: - (1) Visual-flickering
light, visual patterns & specific colors especially red,
leading to rapid blinking or eye closure; (2) Auditorysudden
unexpected noice (startle), specific sounds,
musical themes & voices; (3) Somatosensory-either a
brisk unexpected tap or sudden movement after sitting
or lying still or a prolonged tactile or thermal stimulus to a
certain part of the body (Hot Water Epilepsy); (4) Writing
or reading words or numbers and (5) Eating.
Reading epilepsy is a rare benign, non progressive
syndrome characterized by reading-provoked
sensorimotor symptoms affecting the oral-buccal-lingualfacial
muscles that are involved in reading aloud(2).
However, reading aloud usually not required to trigger
the seizures. As a result, some authorities have
recommended renaming the condition language-induced
Epilepsy(3). Our case was 9 years old male with no
family history, presented as reading epilepsy which was
misdiagnosed for six months as non-organic seizures.
A 9 year old male child used to visit the pediatricians at
different occasions. Always parents complained that most
of the times child starts with abnormal movements of jaw,
face and sometimes myoclonic jerks while reading. He has
3-4 such attacks during school also. Parents and teachers
corelated it as child disintrest toward study. Each attack
used to last for 1-3 minutes. These attacks were more when
he used to read aloud and specifically English language. He
had about twenty attacks in six months time and this has
disturbed the child including his studies. Onexamination child
was well built and neurologically there was no deficit fundus
examination was normal. His BP- 110/70 mm/Hg. & pulse
rate-80/minute, ECG WNL. His biochemical parameters,
sugar, calcium, magnesium, LFT, RFT, haemogram,
blood counts all were normal. His CT scan head was
normal. His EEG was done on 16 channel digital E.E.G.
machine which showed spike wave and polyspike
discharges (Fig. 1).
The child was diagnosed as reading epilepsy and was
put on sodium valproate 300 mg. twice a day. His seizure
completely subsided and now he is doing well in his studies
and he is no more afraid of reading.
Reading epilepsy is a rare, benign non-progressive
syndrome, characterized by reading-provoked
sensorimotor symptoms affecting the oral-buccal-lingualfacial
muscles that are involved in reading aloud (2). This
condition is accompanied by a positive family history of a
similar disorder in as many as one fourth of cases our
patient has no family history and was a sporadic case.
These patients as described b Krishnan et al (4), presents
as myoclonic, jerking or tonic movements of jaw. Some
patients also report with abnormal sensations such as
stiffness, numbness or tightness during the seizures.
Usually disease starts at puberty, the average age of onset
is 17 years with symptoms starting as young as 10 years
of age(4). Cases have been described that overlap
clinically with benign partial epilepsy of childhood
(BPEC), with Juvenile myoclonic epilepsy (JME) and
with absence epilepsy (5, 6,7).
Our case was 9 year old male child who used to get
abnormal movements of jaw, face and myoclonic jerking
while reading English language. All investigations were
normal but detailed history & EEG gave the final diagnosis
and child was treated with sodium valproate and is doing
well and free of seizures.
This rare case has been presented so that clinicians
should be aware and take history properly to reach a
final diagnosis and to treat this benign reflex epilepsy
syndrome effectively.
References
1. Forster FM: Reflex Epilepsy, Behavioral Therapy,
and Conditional Reflexes, Springfield, IL, Charles C
Thomas, 1977.
2. Wolf P., Reading epilepsy. In : Roger J, Bureau M, Dravet
C, Dreifuss F, Perret A, Wolf P, eds. Epileptic Syndromes
in Infancy, Childhood & Adolescence, 2nd edn. London :
John Libbey and Company, 1992 .pp. 281-98.
3. Koutroumanidis M, Koepp MJ, Richardson MP et al. The
variants of Reading Epilepsy. A clinical & video-EEG study
of 17 patients with reading-induced seizures. Brain 1998;
121 : 1409-27.
4. Radhakrishnan K, Silbert PL, Klass DW. Reading epilepsy.
An appraisal of 20 patients diagnosed at the Mayo clinic,
Rochester, Minnesota, between 1949 & 1989, and
delineation of the epileptic syndrome. Brain 1995; 118 :
75-89.
5. Valenti MP, Tinuper P, Cerullo A, Carcangiu R, Marini C :
Reading epilepsy in a patient with previous idiopathic &
focal epilepsy with Centrotemporal spikes. Epileptic
Discord 1999; 1 : 167-171.
6. Wolf P, Mayer T, Reker M. Reading epilepsy. Report of
five new cases and further considerations on the
pathophysiology. Seizure 1998, 7: 271-9.
7. Singh B, Anderson L, al Gashlan M, al Shahwan SA, Riela
AR. Reading-induced absence seizures. Neurology 1995;
45 : 1623-4.
be evoked in certain epileptic individuals by a discrete
physiologic or psychologic stimulus. The term reflex
epilepsy is reserved for this small subgroup. Forster(1)
has classified these seizures in accordance with their
evocative stimuli into five types: - (1) Visual-flickering
light, visual patterns & specific colors especially red,
leading to rapid blinking or eye closure; (2) Auditorysudden
unexpected noice (startle), specific sounds,
musical themes & voices; (3) Somatosensory-either a
brisk unexpected tap or sudden movement after sitting
or lying still or a prolonged tactile or thermal stimulus to a
certain part of the body (Hot Water Epilepsy); (4) Writing
or reading words or numbers and (5) Eating.
Reading epilepsy is a rare benign, non progressive
syndrome characterized by reading-provoked
sensorimotor symptoms affecting the oral-buccal-lingualfacial
muscles that are involved in reading aloud(2).
However, reading aloud usually not required to trigger
the seizures. As a result, some authorities have
recommended renaming the condition language-induced
Epilepsy(3). Our case was 9 years old male with no
family history, presented as reading epilepsy which was
misdiagnosed for six months as non-organic seizures.
A 9 year old male child used to visit the pediatricians at
different occasions. Always parents complained that most
of the times child starts with abnormal movements of jaw,
face and sometimes myoclonic jerks while reading. He has
3-4 such attacks during school also. Parents and teachers
corelated it as child disintrest toward study. Each attack
used to last for 1-3 minutes. These attacks were more when
he used to read aloud and specifically English language. He
had about twenty attacks in six months time and this has
disturbed the child including his studies. Onexamination child
was well built and neurologically there was no deficit fundus
examination was normal. His BP- 110/70 mm/Hg. & pulse
rate-80/minute, ECG WNL. His biochemical parameters,
sugar, calcium, magnesium, LFT, RFT, haemogram,
blood counts all were normal. His CT scan head was
normal. His EEG was done on 16 channel digital E.E.G.
machine which showed spike wave and polyspike
discharges (Fig. 1).
The child was diagnosed as reading epilepsy and was
put on sodium valproate 300 mg. twice a day. His seizure
completely subsided and now he is doing well in his studies
and he is no more afraid of reading.
Reading epilepsy is a rare, benign non-progressive
syndrome, characterized by reading-provoked
sensorimotor symptoms affecting the oral-buccal-lingualfacial
muscles that are involved in reading aloud (2). This
condition is accompanied by a positive family history of a
similar disorder in as many as one fourth of cases our
patient has no family history and was a sporadic case.
These patients as described b Krishnan et al (4), presents
as myoclonic, jerking or tonic movements of jaw. Some
patients also report with abnormal sensations such as
stiffness, numbness or tightness during the seizures.
Usually disease starts at puberty, the average age of onset
is 17 years with symptoms starting as young as 10 years
of age(4). Cases have been described that overlap
clinically with benign partial epilepsy of childhood
(BPEC), with Juvenile myoclonic epilepsy (JME) and
with absence epilepsy (5, 6,7).
Our case was 9 year old male child who used to get
abnormal movements of jaw, face and myoclonic jerking
while reading English language. All investigations were
normal but detailed history & EEG gave the final diagnosis
and child was treated with sodium valproate and is doing
well and free of seizures.
This rare case has been presented so that clinicians
should be aware and take history properly to reach a
final diagnosis and to treat this benign reflex epilepsy
syndrome effectively.
References
1. Forster FM: Reflex Epilepsy, Behavioral Therapy,
and Conditional Reflexes, Springfield, IL, Charles C
Thomas, 1977.
2. Wolf P., Reading epilepsy. In : Roger J, Bureau M, Dravet
C, Dreifuss F, Perret A, Wolf P, eds. Epileptic Syndromes
in Infancy, Childhood & Adolescence, 2nd edn. London :
John Libbey and Company, 1992 .pp. 281-98.
3. Koutroumanidis M, Koepp MJ, Richardson MP et al. The
variants of Reading Epilepsy. A clinical & video-EEG study
of 17 patients with reading-induced seizures. Brain 1998;
121 : 1409-27.
4. Radhakrishnan K, Silbert PL, Klass DW. Reading epilepsy.
An appraisal of 20 patients diagnosed at the Mayo clinic,
Rochester, Minnesota, between 1949 & 1989, and
delineation of the epileptic syndrome. Brain 1995; 118 :
75-89.
5. Valenti MP, Tinuper P, Cerullo A, Carcangiu R, Marini C :
Reading epilepsy in a patient with previous idiopathic &
focal epilepsy with Centrotemporal spikes. Epileptic
Discord 1999; 1 : 167-171.
6. Wolf P, Mayer T, Reker M. Reading epilepsy. Report of
five new cases and further considerations on the
pathophysiology. Seizure 1998, 7: 271-9.
7. Singh B, Anderson L, al Gashlan M, al Shahwan SA, Riela
AR. Reading-induced absence seizures. Neurology 1995;
45 : 1623-4.
Primary Reading Epilepsy
HISTORICAL NOTE AND NOMENCLATURE
Bickford and colleagues first described seizures induced by reading and delineated most of the cardinal clinical features of primary reading epilepsy, defined in patients without spontaneous seizures in whom all attacks were triggered by reading (Bickford et al 1956). Focal, regional, and generalized reflex EEG paroxysmal activity was described in primary reading epilepsy, and the definition of the syndrome did not appear to depend on any single type or localization of EEG abnormality (Ramani 1998). The classification of primary reading epilepsy was thus a matter of interest and debate. Primary reading epilepsy is currently classified as an idiopathic localization-related epilepsy (Commission on Classification and Terminology of the International League Against Epilepsy 1989) and in the proposed revision (which is still in press) is admitted as an Epilepsy Syndrome without specifying whether it is generalized or focal. In this proposal, an epilepsy syndrome is "a complex of signs and symptoms that define a unique epilepsy condition with different etiologies."
CLINICAL MANIFESTATIONS
Primary reading epilepsy consists of seizures triggered by reading, without spontaneous seizures (Bickford et al 1956; Radhakrishnan et al 1995; Koutroumanidis et al 1998; Ramani 1998). Seizures usually begin in adolescence, and onset is unusual in younger children or adults over 30 years old. Patients report jaw jerking or clicking while reading, often with jerks of the arms, and if reading continues, a generalized convulsion may occur. Transient cognitive impairment has also been noted with the jerks. Patients may present with a first convulsion, and a longer history of reading-induced jerks may only then be obtained retrospectively. The developmental history, neurologic examination, interictal EEG, and CT scan are normal. More prolonged reading-induced partial seizures with ictal dyslexia or alexia, possibly speech arrest, and reading-induced bilateral myoclonic seizures and absences have also been reported. A family history of epilepsy is common, and familial reading epilepsy may occur. Koutroumanidis and colleagues noted that many patients had similar attacks with other linguistic tasks (Koutroumanidis et al 1998); reading epilepsy may indeed be a subset of a more broadly-defined reflex epilepsy involving a network for language. This has not yet been sufficiently explored, although it has been reported earlier by Geschwind and Sherwin (Geschwind and Sherwin 1967) and is not defined as a reflex epilepsy syndrome.
CLINICAL VIGNETTE
No information was provided by the author.
ETIOLOGY
The etiology of primary reading epilepsy is unknown.
BIOLOGICAL BASIS
Studies of reading epilepsy suggest that increased task difficulty, increased complexity of different types, and long duration of reading increase the chance of EEG or clinical activation (Christie et al 1988; Wolf et al 1998). Functional imaging in primary reading epilepsy (Koepp et al 1998; Koutroumanidis et al 1998) has shown that these seizures result from activation of parts of a speech and language network in both hemispheres, confirming that the hyperexcitable neuronal tissue forming the critical mass recruited to produce a clinical attack is not necessarily contiguous but is functionally linked (Wolf 1994; Remillard et al 1998). A mechanism similar to that seen in pattern-sensitive epilepsy, in which generalized activity is activated by the occipital cortical stimuli, may operate in many cases of primary reading epilepsy. In primary reading epilepsy, bilateral myoclonic attacks or bilaterally synchronous epileptiform activity is triggered by a functionally localized task activating a functional network, which in affected subjects is hyperexcitable. Evidence for the distribution of this network and for the abnormal activity within it has been obtained from functional imaging (Koepp et al 1998). Pegna and colleagues suggest that seizures triggered by sublexical (non word) reading involve the left hemisphere preferentially, as compared to those triggered by lexical reading, which have bilateral EEG expression (Pegna et al 1999).
EPIDEMIOLOGY
Reading epilepsy is unusual but may be underdiagnosed. The incidence and prevalence are unknown.
PREVENTION
No method of prevention is known.
DIFFERENTIAL DIAGNOSIS
Primary reading epilepsy may be underdiagnosed. If isolated jaw jerks occur without leading to myoclonic jerks, ictal disturbance of spoken language, or a generalized convulsion, the condition may not be recognized as a form of epilepsy. Isolated jaw jerks may be dismissed as a meaningless tic, and associated ictal language disturbance may be ascribed to stuttering or to a movement disorder. Other forms of epilepsy must also be differentiated. Secondary or symptomatic reading epilepsy, typically without jaw jerks, occurs in patients with triggered and spontaneous seizures and must be considered if there are abnormalities on examination, imaging, or the interictal EEG. Pronounced pattern sensitivity may result in seizures during reading due to the pattern of the printed text (Wilkins and Lindsay 1985; Matricardi et al 1991), and some subjects are also sensitive to eye movement.
DIAGNOSTIC WORKUP
EEG helps to confirm the diagnosis. The history may suggest certain texts which are likely to provoke jaw jerks, and using these, events can often be elicited and recorded. Primary reading epilepsy is characterized electrographically by evoked paroxysmal rhythmic theta activity or spikes either over 1 or both frontocentral, centroparietal, or temporoparietal regions in association with jaw jerks. Typically, the left side is involved when activity is unilateral, and it is important to note that bilateral jaw jerks are associated with this unilateral discharge. Many patients with primary reading epilepsy have bilateral or asymmetric myoclonic attacks and bilaterally synchronous spike and wave activity. Unilateral myoclonia has also been reported with bilateral activation (Wolf et al 1998) The interictal EEG is normal, and the patients are not typically photosensitive. Imaging studies do not show gross lesions.
PROGNOSIS AND COMPLICATIONS
Most patients respond well to valproate or to small doses of clonazepam and there is usually no deterioration in neurologic status or in seizure control. The diagnosis must be reconsidered if either of these occur.
MANAGEMENT
Some patients with primary reading epilepsy do not want drug treatment, especially if they have not had generalized convulsions. The patient's particular history must be obtained in detail to devise measures which may reduce the chance of a seizure being triggered. Avoidance of prolonged reading, along with maneuvers that briefly disrupt comprehension or increase arousal may be helpful, but social and educational handicap may arise from these. Audiotaped texts may be useful. Text masking may help those in whom pattern or eye movement contribute to seizure occurrence (Wilkins and Lindsay 1985). These may also be useful if the response to antiepileptic drugs is not complete or if the patient cannot tolerate them. Basic measures such as avoiding sleep deprivation and alcohol excess also apply to these patients. Reading epilepsy has been reported to respond well to valproate and some patients may worsen with carbamazepine (Wolf et al 1998), but clobazam (not marketed in the USA) or clonazepam may also be needed.
PREGNANCY
Not applicable.
ANESTHESIA
No contraindications with anesthesia and primary reading epilepsy are known.
REFERENCES CITED
Bickford RG, Whelan JL, Klass DW, Corbin KB. Reading epilepsy: clinical and electro-encephalographic studies of a new syndrome. Trans Am Neurol Assoc 1956;81:100-2.
Christie S, Guberman A, Tansley BW, Couture M. Primary reading epilepsy: investigation of critical seizure-provoking stimuli. Epilepsia 1988;29(3):288-93.
Commission on Classification and Terminology of the International League Against Epilepsy. Proposal for revised classification of epilepsies and epileptic syndromes. Epilepsia 1989;30:389-99.
Geschwind N, Sherwin I. Language-induced epilepsy. Arch Neurol 1967;16:25-31.
Koepp MJ, Hansen ML, Pressler RM, et al. Comparison of EEG, MRI and PET in reading epilepsy: a case report. Epilepsy Res 1998;29(3):251-7.
Koutroumanidis M, Koepp MJ, Richardson MP, et al. The variants of reading epilepsy. A clinical and video-EEG study of 17 patients with reading-induced seizures. Brain 1998;121:1409-27.
Matricardi M, Brinciotti M, Paciello F. Reading epilepsy with absences, television-induced seizures, and pattern sensitivity. Epilepsy Res 1991;9:145-7.
Pegna AJ, Picard F, Martory MD, et al. Semantically-triggered reading epilepsy: an experimental case study. Cortex 1999;35:101-11.
Radhakrishnan K, Silbert PL, Klass DW. Reading epilepsy. An appraisal of 20 patients diagnosed at the Mayo Clinic, Rochester, Minnesota, between 1949 and 1989, and delineation of the epileptic syndrome. Brain 1995;118:75-89.
Ramani V. Reading epilepsy. In: Zifkin BG, et al, editors. Reflex epilepsies and reflex seizures. Advances in neurology. Vol 75. Philadelphia: Lippincott-Raven Press, 1998:241-62.
Remillard GM, Zifkin BG, Andermann F. Seizures induced by eating. In: Zifkin BG, et al, editors. Reflex epilepsies and reflex seizures. Advances in neurology. Vol 75. Philadelphia: Lippincott-Raven Press, 1998:227-40.
Wilkins AJ, Lindsay J. Common forms of reflex epilepsy: physiological mechanisms and techniques for treatment. In: Pedley TA, Meldrum BS, editors. Recent advances in epilepsy II. Edinburgh: Churchill Livingstone, 1985:239-71.
Wolf P. Reading epilepsy. In: Wolf P, editor. Epileptic seizures and syndromes. London: John Libbey, 1994:67-73.
Wolf P, Mayer T, Reker M. Reading epilepsy: report of five new cases and further considerations on the pathophysiology. Seizure 1998;7(4):271-9.
Bickford and colleagues first described seizures induced by reading and delineated most of the cardinal clinical features of primary reading epilepsy, defined in patients without spontaneous seizures in whom all attacks were triggered by reading (Bickford et al 1956). Focal, regional, and generalized reflex EEG paroxysmal activity was described in primary reading epilepsy, and the definition of the syndrome did not appear to depend on any single type or localization of EEG abnormality (Ramani 1998). The classification of primary reading epilepsy was thus a matter of interest and debate. Primary reading epilepsy is currently classified as an idiopathic localization-related epilepsy (Commission on Classification and Terminology of the International League Against Epilepsy 1989) and in the proposed revision (which is still in press) is admitted as an Epilepsy Syndrome without specifying whether it is generalized or focal. In this proposal, an epilepsy syndrome is "a complex of signs and symptoms that define a unique epilepsy condition with different etiologies."
CLINICAL MANIFESTATIONS
Primary reading epilepsy consists of seizures triggered by reading, without spontaneous seizures (Bickford et al 1956; Radhakrishnan et al 1995; Koutroumanidis et al 1998; Ramani 1998). Seizures usually begin in adolescence, and onset is unusual in younger children or adults over 30 years old. Patients report jaw jerking or clicking while reading, often with jerks of the arms, and if reading continues, a generalized convulsion may occur. Transient cognitive impairment has also been noted with the jerks. Patients may present with a first convulsion, and a longer history of reading-induced jerks may only then be obtained retrospectively. The developmental history, neurologic examination, interictal EEG, and CT scan are normal. More prolonged reading-induced partial seizures with ictal dyslexia or alexia, possibly speech arrest, and reading-induced bilateral myoclonic seizures and absences have also been reported. A family history of epilepsy is common, and familial reading epilepsy may occur. Koutroumanidis and colleagues noted that many patients had similar attacks with other linguistic tasks (Koutroumanidis et al 1998); reading epilepsy may indeed be a subset of a more broadly-defined reflex epilepsy involving a network for language. This has not yet been sufficiently explored, although it has been reported earlier by Geschwind and Sherwin (Geschwind and Sherwin 1967) and is not defined as a reflex epilepsy syndrome.
CLINICAL VIGNETTE
No information was provided by the author.
ETIOLOGY
The etiology of primary reading epilepsy is unknown.
BIOLOGICAL BASIS
Studies of reading epilepsy suggest that increased task difficulty, increased complexity of different types, and long duration of reading increase the chance of EEG or clinical activation (Christie et al 1988; Wolf et al 1998). Functional imaging in primary reading epilepsy (Koepp et al 1998; Koutroumanidis et al 1998) has shown that these seizures result from activation of parts of a speech and language network in both hemispheres, confirming that the hyperexcitable neuronal tissue forming the critical mass recruited to produce a clinical attack is not necessarily contiguous but is functionally linked (Wolf 1994; Remillard et al 1998). A mechanism similar to that seen in pattern-sensitive epilepsy, in which generalized activity is activated by the occipital cortical stimuli, may operate in many cases of primary reading epilepsy. In primary reading epilepsy, bilateral myoclonic attacks or bilaterally synchronous epileptiform activity is triggered by a functionally localized task activating a functional network, which in affected subjects is hyperexcitable. Evidence for the distribution of this network and for the abnormal activity within it has been obtained from functional imaging (Koepp et al 1998). Pegna and colleagues suggest that seizures triggered by sublexical (non word) reading involve the left hemisphere preferentially, as compared to those triggered by lexical reading, which have bilateral EEG expression (Pegna et al 1999).
EPIDEMIOLOGY
Reading epilepsy is unusual but may be underdiagnosed. The incidence and prevalence are unknown.
PREVENTION
No method of prevention is known.
DIFFERENTIAL DIAGNOSIS
Primary reading epilepsy may be underdiagnosed. If isolated jaw jerks occur without leading to myoclonic jerks, ictal disturbance of spoken language, or a generalized convulsion, the condition may not be recognized as a form of epilepsy. Isolated jaw jerks may be dismissed as a meaningless tic, and associated ictal language disturbance may be ascribed to stuttering or to a movement disorder. Other forms of epilepsy must also be differentiated. Secondary or symptomatic reading epilepsy, typically without jaw jerks, occurs in patients with triggered and spontaneous seizures and must be considered if there are abnormalities on examination, imaging, or the interictal EEG. Pronounced pattern sensitivity may result in seizures during reading due to the pattern of the printed text (Wilkins and Lindsay 1985; Matricardi et al 1991), and some subjects are also sensitive to eye movement.
DIAGNOSTIC WORKUP
EEG helps to confirm the diagnosis. The history may suggest certain texts which are likely to provoke jaw jerks, and using these, events can often be elicited and recorded. Primary reading epilepsy is characterized electrographically by evoked paroxysmal rhythmic theta activity or spikes either over 1 or both frontocentral, centroparietal, or temporoparietal regions in association with jaw jerks. Typically, the left side is involved when activity is unilateral, and it is important to note that bilateral jaw jerks are associated with this unilateral discharge. Many patients with primary reading epilepsy have bilateral or asymmetric myoclonic attacks and bilaterally synchronous spike and wave activity. Unilateral myoclonia has also been reported with bilateral activation (Wolf et al 1998) The interictal EEG is normal, and the patients are not typically photosensitive. Imaging studies do not show gross lesions.
PROGNOSIS AND COMPLICATIONS
Most patients respond well to valproate or to small doses of clonazepam and there is usually no deterioration in neurologic status or in seizure control. The diagnosis must be reconsidered if either of these occur.
MANAGEMENT
Some patients with primary reading epilepsy do not want drug treatment, especially if they have not had generalized convulsions. The patient's particular history must be obtained in detail to devise measures which may reduce the chance of a seizure being triggered. Avoidance of prolonged reading, along with maneuvers that briefly disrupt comprehension or increase arousal may be helpful, but social and educational handicap may arise from these. Audiotaped texts may be useful. Text masking may help those in whom pattern or eye movement contribute to seizure occurrence (Wilkins and Lindsay 1985). These may also be useful if the response to antiepileptic drugs is not complete or if the patient cannot tolerate them. Basic measures such as avoiding sleep deprivation and alcohol excess also apply to these patients. Reading epilepsy has been reported to respond well to valproate and some patients may worsen with carbamazepine (Wolf et al 1998), but clobazam (not marketed in the USA) or clonazepam may also be needed.
PREGNANCY
Not applicable.
ANESTHESIA
No contraindications with anesthesia and primary reading epilepsy are known.
REFERENCES CITED
Bickford RG, Whelan JL, Klass DW, Corbin KB. Reading epilepsy: clinical and electro-encephalographic studies of a new syndrome. Trans Am Neurol Assoc 1956;81:100-2.
Christie S, Guberman A, Tansley BW, Couture M. Primary reading epilepsy: investigation of critical seizure-provoking stimuli. Epilepsia 1988;29(3):288-93.
Commission on Classification and Terminology of the International League Against Epilepsy. Proposal for revised classification of epilepsies and epileptic syndromes. Epilepsia 1989;30:389-99.
Geschwind N, Sherwin I. Language-induced epilepsy. Arch Neurol 1967;16:25-31.
Koepp MJ, Hansen ML, Pressler RM, et al. Comparison of EEG, MRI and PET in reading epilepsy: a case report. Epilepsy Res 1998;29(3):251-7.
Koutroumanidis M, Koepp MJ, Richardson MP, et al. The variants of reading epilepsy. A clinical and video-EEG study of 17 patients with reading-induced seizures. Brain 1998;121:1409-27.
Matricardi M, Brinciotti M, Paciello F. Reading epilepsy with absences, television-induced seizures, and pattern sensitivity. Epilepsy Res 1991;9:145-7.
Pegna AJ, Picard F, Martory MD, et al. Semantically-triggered reading epilepsy: an experimental case study. Cortex 1999;35:101-11.
Radhakrishnan K, Silbert PL, Klass DW. Reading epilepsy. An appraisal of 20 patients diagnosed at the Mayo Clinic, Rochester, Minnesota, between 1949 and 1989, and delineation of the epileptic syndrome. Brain 1995;118:75-89.
Ramani V. Reading epilepsy. In: Zifkin BG, et al, editors. Reflex epilepsies and reflex seizures. Advances in neurology. Vol 75. Philadelphia: Lippincott-Raven Press, 1998:241-62.
Remillard GM, Zifkin BG, Andermann F. Seizures induced by eating. In: Zifkin BG, et al, editors. Reflex epilepsies and reflex seizures. Advances in neurology. Vol 75. Philadelphia: Lippincott-Raven Press, 1998:227-40.
Wilkins AJ, Lindsay J. Common forms of reflex epilepsy: physiological mechanisms and techniques for treatment. In: Pedley TA, Meldrum BS, editors. Recent advances in epilepsy II. Edinburgh: Churchill Livingstone, 1985:239-71.
Wolf P. Reading epilepsy. In: Wolf P, editor. Epileptic seizures and syndromes. London: John Libbey, 1994:67-73.
Wolf P, Mayer T, Reker M. Reading epilepsy: report of five new cases and further considerations on the pathophysiology. Seizure 1998;7(4):271-9.
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