Epilepsy partial

Many seizures are associated with distinctive EEG patterns (Fig. 16.1). Perhaps the most striking is the 3 per second spike wave activity seen in most leads (cortical areas) in absence seizures, which can be invoked by hyperventilation. Otherwise distinctive EEG patterns are usually only found during an actual seizure, with burst spiking seen alongside clonus in TCS and abnormal discharges with the behavioural patterns of partial epilepsy and in particular that originating in the temporal lobe. 

I. Localization-related (focal, local, or partial) epilepsies and epileptic syndromes... 

Interestingly, many forms of partial epilepsy are characterized by a seizure-free interval lasting months to years between the occurrence of the causative insult and the emergence of epilepsy termed the latent period , this provides a valuable window of opportunity during which pharmacologic intervention might be implemented in high-risk individuals so that development of epilepsy could be prevented. 

Kalachikov, S., Evgrafov, O., Ross, B. et al. Mutations in LGI1 cause autosomal-dominant partial epilepsy with auditory features. Nat. Genet. 30 335-341, 2002. 

Gabapentin inhibits high-voltage activated Ca channels and elevates human brain GABA levels. It is a second-line agent for patients with partial seizures who have failed initial treatment. It may also have a role in patients with less severe seizure disorders, such as new-onset partial epilepsy, especially in elderly patients. 

An other Cochrane review of nine trials representing 1049 randomized patients concludes Top-iramate has efficacy as an add-on treatment in patients with drug resistant partial epilepsy. However, trials reviewed were of relatively short duration, and provide no evidence for the long term efficacy of top-iramate. Results cannot be extrapolated to monotherapy or patients with other epilepsy types . 

Jette NJ, Marson AG, Hutton JL. Topiramate add-on for drug-resistant partial epilepsy. Cochrane Database Syst Rev 2002. 

Lamotrigine has a broad spectrum of action and is effective in generalized and partial epilepsies. Its primary mechanism of action appears to be blockage of voltage-dependent sodium channels, although its effectiveness against absence seizures indicates that additional mechanisms may be active. Lamotrigine is almost completely... 

High plasma levels of DVP (80-150 pg/mL 555-1,040 pmol/L) are expected to produce significantly more frequent tremors, thrombocytopenia, alopecia, asthenia, diarrhea, vomiting, and anorexia, compared to low serum levels (25-50 j,m/mL 175-345 pmol/L), as shown in a multicenter trial of DVP monotherapy in patients with poorly controlled partial epilepsy (Beydoun et al., 1997). 

Beydoun, A., Sackellares, J.C., and Shu, V. (1997) Safety and efficacy of divalproex sodium monotherapy in partial epilepsy a doubleblind, concentration-response design clinical trial. Depakote Monotherapy for Partial Seizures Study Group. Neurology 48 182-188. 

Semah, F, Gimenez, F, Longer, E., Laplane, D., Thuillier, A., and Baulac, M., (1994) Carbamazepine and its epoxide an open study of efficacy and side effects aftet catbamazepine dose incte-ment in refractory partial epilepsy. Ther Drug Monit 16 537-340. 

It is used in prophylactic treatment of all varieties of partial epilepsy whether or not seizure becomes secondarily generalised. It is also used in prophylactic treatment of generalised convulsive seizures and treatment of status epilepticus prophylactic management of certain forms of supraventricular cardiac arrhythmia as it has an ability to selectively inhibit high frequency firing prophylactic management of certain... 

Gabapentin has been approved in the United States since 1993 for adjunctive use in the management of treatment-refractory partial epilepsy. Early evidence in open-label trials indicated possible mood-stabilizing properties ( 227, 234). Recent data from a placebo-controlled crossover trial, however, found no difference between gabapentin and placebo for manic or depressed episodes (235). 

Vigabatrin is used as an adjunctive antiepileptic in patients with resistant partial epilepsy with or without secondary generalization, unresponsive to other therapy [2]. Nowadays, vigabatrin is rarely used in the treatment of partial seizures due to several irreversible visual field constrictions associated with its chronic use [57-62], It is regarded by many authorities as a drug of choice in infants with west syndrome (infantile spasms), particularly in cases associated with tuberous sclerosis [62],... 

Vigabactin is indicated for second-line use in patients with refractory partial epilepsy but, unlike lamotrigine and topiramate, it does not appear to be useful in generalized epilepsies. It is the drug of choice for infantile spasms. 

F. Andermann, and D.L. Arnold. 2001. Texture analysis and morphological processing of magnetic resonance imaging assist detection of focal cortical dysplasia in extra-temporal partial epilepsy. Ann. Neurol. 49 770-775. 

Henry, T., Bakay, R., Pennell, P., Epstein, C., Votaw, J. (2004). Brain blood-flow alterations induced by therapeutic vagus nerve stimulation in partial epilepsy II. Prolonged effects at high and low levels of stimulation. Epilepsia, 45, 1064-1070. 

Complex visual hallucinations occurred in three patients taking zonisamide for different syndromes and types of seizures (Landau-Kleffner syndrome in a 7-year-old girl, myoclonic and generalized tonic seizures in a 21-year-old woman, and partial epilepsy in a 13-year-old girl) (692). None of the patients had visual hallucinations before zonisamide was started, and the symptoms resolved after withdrawal. 

Neocortical dendritic pathology in human partial epilepsy a quantitative Golgi study. Epilepsia 35 728-36. 

Uses. Phenytoin is used to prevent all types of partial epilepsy, whether or not the seizures thereafter become generalised, and to treat generalised seizures and status epiepticus. It is not used for absence attacks. 

Sodium valproate is effective for a wide range of seizure disorders, including generalised and partial epilepsy, and the prophylaxis of febrile convulsions and post-traumahc epilepsy. 

Simultaneous scalp and depth electrode recordings were performed on five patients with complex partial epilepsy who underwent alfentanil anesthesia induction before depth electrode removal (7). Five equal bolus doses of alfentanil 100 gg were given to each patient at 60-second intervals (total dose 500 gg). Epileptiform activity was increased in three of the five, but without clinical evidence of seizure activity. 

Ross J, Kearse LA Jr, Barlow MK, Houghton KJ, Cosgrove GR. Alfentanil-induced epileptiform activity a simultaneous surface and depth electroencephalographic study in complex partial epilepsy. Epilepsia 2001 42(2) 220-5. 

Visual field defects associated with various antiepUeptic drugs (carbamazepine, diazepam, gabapentin, pheny-toin, tiagabine, and vigabatrin) have been reviewed (19). The true frequency is unknown, but in a retrospective study in 158 patients with partial epilepsy visual field defects were detected in 21 (13%) 13 patients had concentric visual field constriction without subjective spontaneous manifestations. Of these 13 patients, 9 were taking vigabatrin. 

Ganger R, Vignoli A, Bonardi R, Guidolin L. Felbamate in refractory partial epilepsy. Epilepsy Res 1999 34(l) 43-8. 

Carmant L, Holmes GL, Sawyer S, Rifai N, Anderson J, Mikati MA. Efficacy of felbamate in therapy for partial epilepsy in children. J Pediatr 1994 125(3) 481-6. 

In an uncontrolled trial using dosages up to 6000 mg/day in 50 patients with refractory partial epilepsy, tiredness, dizziness, headache, and diplopia were the most common adverse effects (4). At dosages above 3600 mg/day three patients developed flatulence and diarrhea and two had myoclonic jerks. At least in some patients, gabapentin gastrointestinal absorption did not become saturated within the explored dosage range. 

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