Significant Improvement In Seizure Control Research Articles

Management of non-lesional super refractory status epilepticus: a rare case report

Introduction and importance: Super-refractory status epilepticus is defined as status epilepticus that continues or recurs 24 hours or more after the initiation of anesthetic therapy(continuum) a serious medical emergency with a potential for significant morbidity and mortality. Cortisectomy with invasive EEG recording electrocorticography (ECoG) can be a successful treatment option for super-refractory status epilepticus in selected cases, after medical management has failed. Case presentation: we present a case of a young lady who suffered a super refractory status epilepticus and failed five different anti seizure medications, coma producing agents ,IVIG . After failure of multiple medical and sedative therapy cortisectomy was done with the use of invasive EEG recording electrocorticography (ECoG) to tailor and localize the epileptogenic zone. Clinical discussion: When dealing with Status Epilepticus (SE) that is refractory to treatment, early surgical intervention should be taken into consideration as a viable option. Although there are only a few published cases of SE treated with epilepsy surgery, these cases have shown positive outcomes. In fact, one study demonstrated a significant improvement in seizure control for patients with SE who underwent surgical treatment using these techniques. Conclusion: Cortisectomy, which is a rare and invasive procedure, could be considered as a potential treatment for patients who have not responded to multiple medical and sedative therapies.

Gamma Knife Radiosurgery for Hypothalamic Hamartoma: A Multi-Institutional Retrospective Study on Safety, Efficacy, and Complication Profile.

Gamma knife radiosurgery (GKRS) is a safe and effective treatment option for hypothalamic hamartomas (HH), but there is no consensus opinion on its timing, dosage, and follow-up. The aim of this study was to define the safety, efficacy, outcome, and complication profile of GKRS in this patient population. This retrospective multicentric study involved 39 patients with the mean age of 16 ± 14.84 years. Early seizures resulted in an earlier age of diagnosis in 97% of patients. At baseline, no endocrine abnormalities were seen in 75% of patients while 18.9% showed precocious puberty (PP). The median target volume was 0.55 cc (0.1-10.00 cc), and a median margin dose of 16 Gy (8.1-20.0 Gy) was delivered in a single session. All patients were evaluated for clinical, endocrinological, and radiological outcomes. The median follow-up was 5 (0.1-15) years. The median target volume of the cohort was 0.55 (0.35-1.77) cc. The largest HH was of 10 cc. 24/39 (61.5%) were small HH (Regis I-III). At presentation, 94.8% patients suffered from seizures (87.18% with gelastic seizures). 7/39 patients (17.9%) were presented with both PP and epilepsy. Only one (2.6%) patient presented with PP alone. 29 patients had more than 3-year follow-up. All received ≥16 Gy targeting complete HH. 28% of patients showed regression in HH volume. Patients with Regis grade I-III and longer follow-up (>75 months) showed gradual improvement in seizures. 16/29 patients (55.2%) achieved good seizure control (Engel I/II) while 13 (44.8%) were in Engel III/IV status. Nine patients needed adjuvant treatment because of poor seizure control. Eight patients suffered from transient increase in seizures. One patient developed poikilothermia, and 2 patients developed new onset hormonal deficiency. GKRS is a safe and effective modality for treatment of HH with significant improvement in seizure control with minimal disruption of endocrine profile. It provides an excellent safety, efficacy, and complication profile, especially for small HH. Latency of results and its adjuvant nature remain the areas of research and breakthroughs among contemporary treatment options.

Responsive neurostimulation of the thalamus improves seizure control in idiopathic generalised epilepsy: initial case series

ObjectivesUp to 40% of patients with idiopathic generalised epilepsy (IGE) are drug resistant and potentially could benefit from intracranial neuromodulation of the seizure circuit. We present outcomes following 2 years...

Efficacy and tolerability of hydroalcoholic extract of Paeonia officinalis in children with intractable epilepsy: An open-label pilot study

Despite a wide range of medications available to control epilepsy, seizures in more than 30 % of patients remain uncontrolled. However, in traditional medicine, Paeonia officinalis (P. officinalis), a native perennial herb of Southern Europe and Western Asia, has been used for an anticonvulsant effect for over 2000 years globally. In an open-label pilot study implemented on 30 children with intractable epilepsy aged 1−14 years, the hydroalcoholic extract of P. officinalis was administered. This study’s purpose was to assess the efficacy and tolerability of the P. officinalis extract as an adjunct therapy to a patient’s antiseizure medications in reducing the frequency and duration of the seizures in childhood intractable epilepsy. The mean frequency of seizures decreased significantly during treatment with the P. officinalis extract (P < 0.05). At the end of the intervention, 62.5 % and 36.7 % of the patients showed a≥50 % and a≥75 % reduction in seizure frequency, respectively. Regarding safety and tolerability, no serious adverse events occurred during the trial, although restlessness was reported in one child and the other children who experienced constipation, stopped treatment. The results show that the P. officinalis root extract was well tolerated and has contributed to a significant improvement in seizure control in children with medically intractable epilepsy. This trial was registered with the Iranian Registry of Clinical Trials (www.irct.ir; registration number: IRCT20131125015533N2.

The outcome of altering antiepileptic drug therapy before pregnancy

We investigated the outcome of altering antiepileptic drug (AED) therapy in the year before pregnancy on 2233 occasions in Australian women in the 20-year period of functioning of the Raoul Wallenberg Australian Pregnancy Register (APR).Therapy had been altered in 358 instances (16%) in the months prior to the pregnancy (median interval: 18 weeks). Antiepileptic drug doses had been changed in 141 pregnancies (39.4%), being decreased in 94; drugs changed in 151 (42.2%); drugs withdrawn without replacement in 66 (18.4%) but resumed in 40 before pregnancy ended. The main drugs involved were valproate (34%), phenytoin (16.5%), topiramate (12.6%), and carbamazepine (11.4%). Antiepileptic drug doses were increased significantly more often (16.9% vs. 6.4%) when epilepsy before pregnancy was not controlled, and AED treatment ceased significantly less often (13.6% vs. 24.0%). The alterations were more often made in women with generalized epilepsies and in those whose seizure disorders were not fully controlled in the prepregnancy year, suggesting that avoidance of teratogenicity and achieving improved seizure control often motivated the changes.Overall, the alterations did not result in improved rates of seizure freedom during pregnancy, as compared with pregnancies where therapy was unchanged; however, fetal malformation rates were lower 3.6% vs. 5.4%, but this difference did not attain statistical significance. The same trends regarding seizure control and malformations persisted after pregnancies involving valproate exposure were excluded.In conclusion, this analysis of the APR cohort did not demonstrate that altering AEDs before pregnancy produced a significant improvement in seizure control and the reduction in fetal malformation rate that occurred was not statistically significant.

Multimodal pathway for brain tumor-related epilepsy patients: Observational study.

Brain tumor-related epilepsy patients (BTRE) have a complex profile due to the simultaneous presence of two pathologies: brain tumor and epilepsy. That illness and their treatments could induce physical, cognitive, emotional disturbances, and possible social isolation, with detrimental effect on patients' quality of life (QoL). Aim of this observational pilot study is to evaluate whether a multimodal rehabilitation pathway (MRP) consisting of epileptological follow-up, neurocognitive training, emotional support, and social support could produce an improvement in perceived quality of life of 33 patients with BTRE. Basal (T0) and 6month (T1) evaluation with epileptological, neuropsychological, psychological state (Symptom checklist-SCL-90), social (Social questionnaire schedule-SQS), and QoL assessment (QOLIE 31-P). MRP consisted in epileptological follow-up, supportive meeting groups, social assistance; patients with cognitive deficits could also obtain a 12-week neurocognitive training. We observed at T1 significant improvements in mean seizure/month (P=.02), verbal memory (word list immediate recall, P=.01; word list delayed recall P=.003), social aspects with regard to assistencial network's efficacy (SQS network P=.001) and quality of social relations (SQS socialization P<.0001). QOLIE 31-P showed a significant improvement in cognitive scale (P=.04) and a significant decrease in cognitive related distress (P=.04). No psychopathological symptoms were detected. After 6months, MRP produced significant improvements in seizure control, cognitive performances, quality of social relations, patients' perception to be supported and patients' perceived quality of life related to cognitive efficacy. Future randomized trial with longer follow-up is needed to further evaluate the impact of this kind of pathway on patients' QoL.

Children with autism spectrum disorders and drug-resistant epilepsy can benefit from epilepsy surgery

ObjectiveThe objective of this research was to evaluate a cohort of children with both autism spectrum disorder (ASD) and drug-resistant epilepsy (DRE) after epilepsy surgery to determine predictors of best outcome. MethodsRetrospective chart review was done for 29 children ages 2 to 18 years with ASD and DRE who had neurosurgical intervention for seizure management over 15 years at one institution. All subjects had at least 1 year of follow-up. Data abstraction included demographic information, seizure diagnosis, treatment, investigations, surgical intervention, neuropsychological assessment, and outcome. Statistical analysis software (SAS) was used for statistical analysis. Engel classification was used to assess seizure outcome. ResultsFifteen subjects had resective surgery. Fourteen had palliative surgery with vagal nerve stimulator (VNS) insertion (13) and corpus callosotomy (1). Of the 29 subjects, 35% had class I outcome (all in the resective group). When combining all subjects (resective and palliative), 66% of subjects benefited with class I–III outcomes. In the total cohort, age at time of surgery was significant, with class I outcome more frequently seen in the younger age group when compared with classes II–IV (p = 0.01). ConclusionA subset of children with ASD can benefit from resective surgery, and for those who are not candidates, a VNS can offer significant improvements in seizure control.

Effectiveness and Adverse Effect of Intravenous Lacosamide in Nonconvulsive Status Epilepticus and Acute Repetitive Seizures in Children.

Nonconvulsive status epilepticus (NCSE) and acute repetitive seizures (ARS) are associated with significant morbidity and mortality. Due to the lack of randomized-controlled trials of intravenous antiepileptic drugs (AEDs) in these conditions, trials of a new generation of AEDs in this aspect are needed. A prospective interventional study was conducted in children under 18 years of age with NCSE or ARS who either had contraindication to or were refractory to first-line AEDs and received intravenous lacosamide. Demographic data, the efficacy of treatment, and adverse effects were recorded. Eleven patients with a median age of 11 years, predominantly female (72.7%), were enrolled. Average loading dose was 227 mg (8.3 mg/kg/dose) and average daily maintenance dose was 249 mg (4.6 mg/kg/dose). All patients (100%) experienced a reduction in seizure frequency within 24 hours. Eight of eleven patients (72.7%) experienced a reduction in seizure frequency of more than 50% by the end of the study, and one patient became seizure-free. In terms of adverse events, one patient had a bradycardia without prolongation of the PR interval. Interestingly, there was a case of neuronal ceroid lipofuscinosis in which a significant improvement in seizure control was achieved. The results indicate that intravenous lacosamide may be an alternative treatment for NCSE or ARS in children. To our knowledge, this is the first study on the use of intravenous lacosamide in Asian children. This study is registered to Thai Clinical Trials Registry (TCTR) and the trial registration number is TCTR20180508004.

Repeat surgery for focal cortical dysplasias in children: indications and outcomes

OBJECTIVE Focal cortical dysplasia (FCD) is a common cause of medically intractable epilepsy that often may be treated by surgery. Following resection, many patients continue to experience seizures, necessitating a decision for further surgery to achieve the desired seizure outcomes. Few studies exist on the efficacy of reoperation for intractable epilepsy due to FCD in pediatric cohorts, including the definition of prognostic factors correlated with clinical benefit from further resection. METHODS The authors retrospectively analyzed the medical records and MR images of 22 consecutive pediatric patients who underwent repeat FCD resection after unsuccessful first surgery at the Children's National Health System between March 2005 and April 2015. RESULTS Accounting for all reoperations, 13 (59%) of the 22 patients achieved complete seizure freedom and another 5 patients (23%) achieved significant improvement in seizure control. Univariate analysis demonstrated that concordance in electrocorticography (ECoG) and MRI localization (p = 0.005), and completeness of resection (p = 0.0001), were associated with seizure freedom after the first reoperation. Patients with discordant ECoG and MRI findings ultimately benefited from aggressive multilobe lobectomy or hemispherectomy. Repeat lesionectomies utilizing intraoperative MRI (iMRI; n = 9) achieved complete resection and seizure freedom in all cases. CONCLUSIONS Reoperation may be clinically beneficial in patients with intractable epilepsy due to FCD. Patients with concordant intraoperative ECoG and MRI localization may benefit from extended resection of residual dysplasia at the margins of the previous lesional cavity, and iMRI may offer benefits as a quality control mechanism to ensure that a complete resection has been accomplished. Patients with discordant findings may benefit from more aggressive resections at earlier stages to achieve better seizure control and ensure functional plasticity.

Surgical Resection for Epilepsy Following Cerebral Gunshot Wounds

The surgical management of epilepsy after penetrating gunshot wounds (GSWs) to the head has not been described in the modern era. Given the extensive damage to the cranium and cortex from such injuries, the safety and efficacy of surgical intervention are unclear. We report surgical strategy and outcomes after resection for medically refractory epilepsy following GSWs in 4 patients. A prospectively compiled database of 325 patients with epilepsy was used to identify patients undergoing surgery for medically refractory epilepsy after a GSW to the brain. Seizure frequency, scalp and intracranial electroencephalography evaluation, type of resection, and seizure outcomes were compiled. All 4 patients underwent direct electrocorticography recordings either with implanted electrodes or intraoperatively that were used to drive surgical decision making. All patients had intracranial shrapnel fragments and large areas of encephalomalacia on imaging. Intracranial electrodes were placed in 2 patients to localize seizure onsets. Two patients underwent frontal lobe resections, and the other 2 patients underwent multilobar resections. Latency between injury and epilepsy surgery was 12 years, and mean age at surgery was 28 years. In all cases, epilepsy surgery led to a significant improvement in seizure control (Engel class I, 2 patients; II, 1 patient; and III, 1 patient). Epilepsy is common after penetrating head injury, and the incidence is likely to increase given the growing numbers of armed conflicts in urban centers worldwide. In selected cases, intracranial monitoring and surgical resections may be safely performed and can lead to favorable seizure outcomes.

Low dose verapamil as an adjunct therapy for medically refractory epilepsy – An open label pilot study

Previous studies using verapamil as an adjunct therapy to anti-seizure medications have used doses ranging from 120 to 240mg per day. However, despite showing promising results, there was an increased incidence of side effects. The aim of this study is to assess the efficacy and tolerability of low dose verapamil (20mg p.o. tid) as adjunct therapy to patient’s anti-seizure medications irrespective of the type or etiology of the epilepsy. In an open-label pilot study we enrolled 20 adult patients with history of epilepsy who continued to have a minimum of 2 seizures a month despite being on or having tried maximum tolerated doses of 3 or more standard antiepileptic drugs under the supervision of an epileptologist. 10 of the 19 patients (53%) who continued in the study had >50% reduction in seizure frequency. 2 of the patients (10%) had <50% seizure reduction. The remaining 7 patients (37%) had no reduction in their seizures. There was no discontinuation due to adverse events. P-Glycoprotein is a prototypical drug transporter that has been strongly implicated in drug resistance in epilepsy. Verapamil at a relatively low dose was well tolerated compared to previous studies which used up to 240mg per day and seems to have contributed to a statistically significant improvement in seizure control in patients with medically refractory epilepsy, especially in patients with Lennox-Gastaut syndrome. A randomized double blind controlled study at this low dose with larger sample size may be more informative.

Treatment changes in a cohort of people with apparently drug-resistant epilepsy: an extended follow-up

BackgroundThe seizure response to the addition of a previously unused antiepileptic drug in a cohort of 155 people with refractory epilepsy was previously reported after a median of 18 months...

Vagus nerve stimulation: effectiveness and tolerability in 64 paediatric patients with refractory epilepsies

We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 64 paediatric patients with refractory epilepsies. Sixty-four patients (34 male and 30 female) implanted with VNS for refractory epilepsy were analysed. Electroclinical features were compatible with Lennox-Gastaut syndrome in 46 patients, focal epilepsies in 10 patients, Dravet syndrome in three patients, epilepsy with myoclonic-astatic seizures in three patients, and West syndrome in two. The NeuroCybernetic Prosthesis (NCP) system (Cyberonics, Webster, TX, USA) was employed and the following stimulation parameters were used: output current of 1 to 2.5mA, signal frequency of 30Hz, signal pulse width of 500μs, and signal "on" and "off" times of 30 seconds and 5 minutes, respectively. Of 46 patients with LGS, 30 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Ten patients with focal epilepsy, three patients with myoclonic-astatic seizures, two patients with Dravet, and two patients with West showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In a significant number of patients, reduced seizure severity and shorter recovery time and hospital stay were also observed. VNS was well tolerated in all patients. VNS is an effective and well-tolerated treatment for paediatric patients with refractory epilepsies, improving quality of life and neuropsychological performance.

Clobazam approved for seizure disorder

FDA and Lundbeck Inc. on October 24 announced the approval of clobazam oral tablets as adjunctive therapy for the prevention of seizures in children 2 years of age or older who have Lennox syndrome. Lundbeck will market the drug in the United States as Onfi. The company expects the tablets to be available in early January. Clobazam, a benzodiazapene, has been classified in the United States as a Schedule IV controlled substance. A medication guide must be distributed with each filled prescription of the drug. According to the National Institute of Neurologic Disorders and Stroke, Lennox syndrome is a severe form of epilepsy characterized by frequent seizures of different types that often first occur in children under 4 years of age. Most children with the syndrome suffer from cognitive and developmental problems. In clinical trials, the addition of clobazam to study participants’ antiseizure medication regimen improved seizure control when compared to placebo. The response was dose dependent, with a significant improvement in seizure control in patients taking the highest studied dose compared to the lowest.

Short-course of prednisolone in solitary cysticercus granuloma: A randomized, double-blind, placebo-controlled trial

To determine the effect of administration of a short course of prednisolone on seizure and radiologic outcome in patients with solitary cysticercus granuloma (SCG). One hundred forty-eight subjects presenting with new-onset seizures (<15 days duration) and with SCG demonstrated on imaging studies were randomly allocated to either treatment with prednisolone (40-60 mg/day for 2 weeks) or placebo in addition to standard antiepileptic drug therapy. The subjects were followed up for seizure recurrence for 9 months. Repeat computed tomography (CT, at 3 months) and magnetic resonance imaging (MRI, at 6 months) to evaluate resolution and calcification of the lesion. There was no difference in the proportion of subjects with seizure recurrence during the follow-up period in the treatment (n = 16, 21.9%) and control (n = 19, 25.33%) groups (p = 0.7). However, generalized seizures occurred in a significantly lesser proportion of subjects in the treatment group (n = 3, 15.79%) in comparison to the control group (n = 12, 60.00%) (p = 0.015). There were no significant differences in the proportion of subjects with complete resolution of the SCG on repeat CT at 3 months [treatment group (27, 46.7%) and control group (23, 39.8%); p = 0.453] and repeat MRI at 6 months [treatment group (28, 46.7%) and control group (21, 38.9%); p = 0.402]. The administration of a short course of prednisolone does not offer significant improvement in seizure control, although a benefit in terms of reducing the likelihood of generalized seizures is possible. Furthermore, it does not improve the chances of resolution of the SCG on follow-up imaging studies.

Rufinamide for the treatment of Lennox–Gastaut syndrome

Introduction: Lennox–Gastaut syndrome (LGS) is a severe treatment-resistant childhood-onset epilepsy. This review examines the role of the new drug rufinamide for the treatment of LGS.Areas covered: MEDLINE and Google Scholar searches were undertaken. The pharmaceutical company was contacted for the latest information. LGS is characterized by the triad of diffuse slow spike–wave discharges in the electroencephalogram (EEG), learning disability (mental retardation) and frequent generalized seizures of multiple types, usually including tonic, atonic and atypical absence seizures. Felbamate, lamotrigine and topiramate have resulted in significant reductions in some seizure types, but no treatment has achieved acceptable seizure control in most patients. In a pivotal randomized, double-blind, placebo-controlled trial, the new drug rufinamide achieved significant improvements in seizure control in previously resistant subjects when added to up to three concomitant antiepileptic drugs. Open studies including patients with LGS have also demonstrated efficacy. These trials and a large open trial in adults and adolescents with partial seizures have revealed no serious adverse effects so far. The most common adverse events were fatigue/somnolence and vomiting. Rufinamide is of value in decreasing seizure frequency in LGS, but seizure freedom is seldom achieved. Although no serious adverse effects have been identified, the limited data available at present allow no firm conclusions to be drawn with regard to safety.Expert opinion: The data support a role for rufinamide in treating LGS. However, more efforts are required to provide antiepileptic drugs for this treatment-resistant epilepsy syndrome. Rufinamide might also be of value in treating other forms of epilepsy.

Clobazam as an adjunctive therapy in treating seizures associated with Lennox&amp;ndash;Gastaut syndrome

Lennox–Gastaut syndrome (LGS) is a devastating childhood epilepsy syndrome characterized by the occurrence of multiple types of seizures and cognitive decline. Most children suffer from frequent seizures that are refractory to current medical management. Recent clinical trials have suggested that addition of clobazam may improve the clinical outcome for some LGS patients. Although clobazam has been available for over five decades, it has only recently been approved by the US Food and Drug Administration for this indication. As a 1,5-benzodiazepine, clobazam is structurally related to the widely used 1,4-benzodiazepines, which include diazepam. Clobazam has been shown to modulate GABAergic neurotransmission by positive allosteric modulation of GABAA receptors, and to increase expression of transporters for both GABA and glutamate. The active metabolite n-desmethylclobazam (norclobazam) also modulates GABAA receptors, and the relative importance of these two compounds in the clinical effectiveness of clobazam remains an open question. Clinical trials involving clobazam as an addon therapy in a variety of pediatric epilepsy populations have found a significant improvement in seizure control. In patients with LGS, clobazam may have greatest efficacy for drop seizures. Longstanding clinical experience suggests that clobazam is a safe and well tolerated antiepileptic drug with infrequent and mild adverse effects. These results suggest that adjunctive treatment with clobazam may be a reasonable option for LGS patients, particularly those who are treatment-resistant.

Vagus nerve stimulation: effectiveness and tolerability in patients with epileptic encephalopathies

We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 26 patients with refractory epileptic encephalopathies (EEs). Twenty-six patients (17 male and 9 female) with electroclinical features compatible with Lennox-Gastaut syndrome (LGS) in 20 patients, Dravet syndrome (DS) in 3 patients, and epilepsy with myoclonic-astatic seizures (EMAS) in 3 patients implanted with the NCP system were analyzed. In our series of patients with LGS, 17 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Seven of them previously had epileptic spasms. Three patients with EMAS and two patients with DS showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In patients who had a reduction in seizure frequency of at least 50%, quality of life (QOL) and neuropsychological performance improved. VNS was well-tolerated in all patients. VNS is an effective and well-tolerated treatment for patients with epileptic encephalopathies EEs, improving QOL and neuropsychological performance.

Epilepsy Surgery Outcomes: Quality of Life and Seizure Control

A consecutive, retrospective analysis of seizure control and quality of life was performed among 83 pediatric patients undergoing epilepsy surgery at Children's Hospital of Wisconsin. Seizure outcomes were generally favorable, with 68.7% class I outcomes; class II, 12%; and class III, 19.3%. Seizure freedom was highest among temporal lobectomies (84.2%) and hemispherectomies (76.2%). Outcomes among hemispherectomies were substantially superior to those of multilobar resections. Cortical dysplasia was associated with lower seizure freedom, at 57.5%. Among age groups, seizure-free outcomes in infants were lowest, at 50%. The lower infant seizure-free rate was likely attributable to frequency of multilobar resections and type of pathology (cortical dysplasia). Quality-of-life measures generally paralleled seizure outcomes. These results indicate that epilepsy surgery in children with intractable epilepsy can result in significant improvements in seizure control, quality of life, and development. Anticipated type of surgery, presumed location of epileptogenic site, absence of a defined lesion on magnetic resonance imaging scan of the brain, and patient's age should not prevent surgical evaluations of children with intractable epilepsy.

Supplementary implantation of intracranial electrodes in the evaluation for epilepsy surgery

In some patients, resective epilepsy surgery can be planned based on a non-invasive work-up. However, in many cases, invasive monitoring with intracranial electrodes is required prior to recommending a resective procedure. Although the results of intracranial recordings are usually conclusive, a small group of patients may require additional electrodes to better define the seizure onset or propagation. One hundred and seventy seven patients who underwent intracranial electrode insertion between January 2000 and June 2005 were reviewed. Twelve of these patients required a supplementary implantation prior to making a recommendation about resective surgery. We report the nature of implantation as well as the outcomes in these 12 patients. The mean age of these patients was 35 years (7 males). An average of 2.5 additional strip electrodes were required resulting in a mean of 9 strip type electrodes per patient, for a mean total of an additional 20 days. For most patients (9/12) this subsequent procedure identified an area of epileptic cortex other than that originally hypothesized. Seven patients went on to surgery of which three experienced a significant improvement in seizure control. The addition of supplementary electrodes to an ongoing invasive electrode investigation can be a useful means of clarifying a patient's suitability for a resective surgical procedure. While the surgical outcomes may not be as favorable as in patients in whom the investigations are simpler, a proportion of these patients do benefit from the eventual resective procedure. In cases where the supplementary electrodes lead to the conclusion that surgery is not indicated, these patients can be satisfied that the surgical option has been explored to the fullest extent possible.