Surgical Treatment of Temporoparietooccipital Cortical Dysplasia in Infants: Report of Two Cases

Surgical treatment of epilepsy in a patient with bilateral periventricular nodular heterotopia: A case report

Background

Periventricular nodular heterotopia (PNH) is a rare pathological condition characterized by the presence of nodules of gray matter located along the lateral ventricles of the brain. The condition typically presents with seizures and other neurological symptoms, and various methods of surgical treatment and postoperative outcomes have been described in the literature.

Case Description

We present a case study of a 17-year-old patient who has been experiencing seizures since the age of 13. The patient reported episodes of loss of consciousness and periodic freezing with preservation of posture. Two years later, the patient experienced his first generalized tonic-clonic seizure during nocturnal sleep and was subsequently admitted to a neurological department. A magnetic resonance imaging scan of the brain with an epilepsy protocol (3 Tesla) confirmed the presence of an extended bilateral subependymal nodular heterotopy at the level of the temporal and occipital horns of the lateral ventricles, which was larger on the left side, and a focal subcortical heterotopy of the right cerebellar hemisphere. The patient underwent a posterior quadrant disconnection surgery, which aimed to isolate the extensive epileptogenic zone in the left temporal, parietal, and occipital lobes using standard techniques. As of today, 6 months have passed since the surgery and there have been no registered epileptic seizures during this period following the surgical treatment.

Conclusion

Although PNHs can be extensive and located bilaterally, surgical intervention may still be an effective way to achieve seizure control in selected cases.

Seizure outcomes of large volume temporo-parieto-occipital and frontal surgery in children with drug-resistant epilepsy

OBJECTIVE

In this study, we investigate the seizure outcomes of temporo-parieto-occipital (TPO) and frontal disconnections or resections in children with drug-resistant epilepsy (DRE) in order to determine factors which may predict surgical results.

METHODS

Children with DRE, who underwent either TPO or frontal disconnection or resection at Great Ormond Street Hospital for Children between 2000 and 2017, were identified from a prospectively collated operative database. Demographic data, age at surgery, type of surgery, scalp EEGs and operative histopathology were collected. Magnetic resonance imaging (MRI) was assessed to determine completeness of disconnection and presence of radiological lesion beyond the disconnection margins. Seizure outcome at 6, 12, and 24 months post-surgery was assessed using the Engel Scale (ES). Logistic regression was used to identify relationships between data variables and seizure outcome.

RESULTS

46 children (males = 28, females = 18; age range 0.5-16.6 years) who underwent TPO (n = 32, including a re-do disconnection) or frontal disconnection or resection (n = 15) were identified. Patients in the TPO treatment group had more favourable seizure outcomes than those in the frontal treatment group (ES I-II in 56 %vs 47 % at 6 months, 52 % vs 46 % at 12 months). Presence of the lesion beyond disconnection boundaries and older age at the time of surgery were associated with poorer seizure outcome. Gender, surgery type, completeness of disconnection, scalp EEG findings and underlying pathology were not related to seizure outcome, but subgroup numbers were small.

CONCLUSIONS

Both TPO and frontal disconnection are effective treatments for selected children with posterior multi-lobar or diffuse frontal lobe epilepsy. Confinement of the MRI lesion within the disconnection margins and a younger age at surgery are associated with favourable seizure outcomes. Further studies are required to elucidate these findings.

Total and partial posterior quadrant disconnection for medically refractory epilepsy: A systematic review

PURPOSE

Posterior quadrant disconnection (PQD) is a surgical procedure for medically refractory epilepsy (MRE) involving diffuse regions of the temporo-parieto-occipital lobes. We sought to compare factors and efficacy according to PQD extent.

METHODS

We performed a systematic review of the literature reporting the use of PQD since 2004. We analyzed various characteristics of pooled cases, including the role of preoperative studies in patient selection, intraoperative techniques, and outcomes.

RESULTS

Our review of 137 patients from nine studies revealed 66% undergoing total PQD and 34% undergoing partial PQD. Interictal electroencephalography (EEG) findings were predominantly characterized as lateralized for total PQD (56%) and localized within the ipsilateral posterior quadrant in patients undergoing partial PQD (53%). Metabolic functional studies [positron emission tomography (PET) or ictal single-photon emission computed tomography (SPECT)] played a role in surgical decision-making in 42% of patients who underwent total PQD. Wada and/or functional magnetic resonance imaging (fMRI) was more often utilized for partial PQD (22%) than total PQD (3%) as was intracranial electroencephalography (icEEG) (30% versus 13%, respectively). Overall, 75% of total PQD patients achieved seizure freedom [defined as Engel I or International League Against Epilepsy (ILAE) Class 1 outcome] in comparison to 63% of partial PQD patients (p = .078). New visual field deficits were seen in 12% and new or worsened hemiparesis in 6%. For patients in either cohort, concordance of interictal and ictal EEG findings was found to be predictive of seizure freedom (p = .048).

CONCLUSION

Both total and partial PQD represent effective alternatives for managing patients with MRE whose seizure onset zone (SOZ) involves a diffuse region within the posterior quadrant. While PET and/or SPECT frequently aided in the decision to proceed with total PQD, patients who underwent a tailored, partial multilobar resection were more likely to undergo Wada and/or fMRI testing as well as stage I icEEG studies.

Unilateral prefrontal lobotomy for epilepsy: technique and surgical anatomy

OBJECTIVE

Surgery for frontal lobe epilepsy remains a challenge because of the variable seizure outcomes after surgery. Disconnective procedures are increasingly applied to isolate the epileptogenic focus and avoid complications related to extensive brain resection. Previously, the authors described the anterior quadrant disconnection procedure to treat large frontal lobe lesions extending up to but not involving the primary motor cortex. In this article, they describe a surgical technique for unilateral disconnection of the prefrontal cortex, while providing an accurate description of the surgical and functional anatomy of this disconnective procedure.

METHODS

The authors report the surgical treatment of a 5-month-old boy who presented with refractory epilepsy due to extensive cortical dysplasia of the left prefrontal lobe. In addition, with the aim of both describing the subcortical intrinsic anatomy and illustrating the different connections between the prefrontal lobe and the rest of the brain, the authors dissected six human cadaveric brain hemispheres. These dissections were performed from lateral to medial and from medial to lateral to reveal the various tracts sectioned during the three different steps in the surgery, namely the intrafrontal disconnection, anterior callosotomy, and frontobasal disconnection.

RESULTS

The first step of the dissection involves cutting the U-fibers. During the anterior intrafrontal disconnection, the superior longitudinal fasciculus in the depth of the middle frontal gyrus, the uncinate fasciculus, and the inferior frontooccipital fasciculus in the depth of the inferior frontal gyrus at the level of the anterior insular point are visualized and sectioned, followed by sectioning of the anterior limb of the internal capsule. Once the frontal horn is reached, the anterior callosotomy can be performed to disconnect the genu and the rostrum of the corpus callosum. The intrafrontal disconnection is deepened toward the falx, and at the medial surface, the cingulum is sectioned. The frontobasal disconnection involves cutting the anterior limb of the anterior commissure.

CONCLUSIONS

This technique allows selective isolation of the epileptogenic focus located in the prefrontal lobe to avoid secondary propagation. Understanding the surface and white matter fiber anatomy is essential to safely perform the procedure and obtain a favorable seizure outcome.

Posterior Quadrant Disconnection for Childhood Onset Sub-Hemispheric Posterior Head Region Epilepsy: Indications in an Indian Cohort and Outcome

BACKGROUND

Posterior quadrant disconnection (PQD) is an under-utilized surgical technique in the management of refractory epilepsy. There is a dearth of data pertinent to post-PQD seizure outcomes.

METHODS

This retrospective study analyzed patients with drug-resistant childhood-onset epilepsy who underwent PQD at our center from 2009 to 2018. The clinical, imaging, and electrophysiological data were reviewed. The seizure outcome was noted from the latest follow-up in all patients.

RESULTS

Fifteen patients underwent PQD, with a mean age at onset of epilepsy of 3.3 ± 4.6 years. All patients had seizure onset in childhood with focal onset of seizures, and in addition, 5 had multiple seizure types. All cases underwent presurgical workup with MRI, video-EEG, psychometry, while PET/MEG was done if required. Engel Ia and ILAE I outcomes were considered to be favorable. The histology of the specimen showed 9 patients (60%) had gliosis, 4 (26.7%) had focal cortical dysplasia (FCD), while 1 patient had nodular heterotopia and another had polymicrogyria-pachygyria complex. Postoperative follow-up was available in 14 cases. One patient was lost to follow-up. Mean follow-up duration for the cohort was 45 + 24 months. At last, follow-up (n = 14), 66.7% (10 cases) had favorable outcome (Engel Ia). At the end of 1-year follow-up, up to 73% (n = 11) of the patients were seizure-free. Four patients developed transient hemiparesis after surgery which improved completely by 3-6 months.

CONCLUSIONS

Gliosis was more common etiology requiring PQD in our series than Western series, where FCD was more common. PQD is a safe and effective surgical modality in childhood-onset epilepsy with posterior head region epileptogenic focus.

Operative posterior disconnection in epilepsy surgery: Experience with 29 patients

OBJECTIVE

It has been suggested that multilobar epilepsies caused by lesions restricted to the posterior cerebral quadrant (ie, the parietal, temporal, and occipital lobes) can be treated successfully by a procedure termed posterior disconnection. The objective of the present paper was to identify determinants of the epileptological outcome following posterior disconnection surgery.

METHODS

The authors retrospectively analyzed a series of 29 consecutive patients undergoing posterior disconnection surgery between 2005 and 2017 for the treatment of refractory posterior quadrantic epilepsy. Specifically, all presurgical and postoperative magnetic resonance (MR) studies were reviewed to identify cases with an incomplete disconnection, or the presence of a more widespread pathology involving the whole hemisphere rather than only its posterior quadrant. In addition, we reevaluated all presurgical video-electroencephalography (EEG) reports.

RESULTS

Seizure-free (International League Against Epilepsy [ILAE] 1) after surgery were 3/3 patients with EEG findings restricted to the posterior quadrant, 0/7 patients who had propagation of epileptic activity to the contralateral frontal lobe, and 11/19 (57.9%) who showed propagation to ipsilateral frontal and/or contralateral posterior. Eleven of 13 (84.6%) patients with purely posterior quadrantic magnetic resonance imaging (MRI) findings (as retrospectively diagnosed by neuroimaging) vs 3/16 (18.8%) cases with additional subtle abnormalities outside the posterior quadrant became seizure-free (P = .001). Eleven of 16 (68.8%) patients with complete disconnections were seizure-free vs only 3/13 (23.0%) cases with leftover temporal lobe tissue with contact to the insula (P = .025, both Fisher's exact test).

SIGNIFICANCE

A posterior disconnection is a technically demanding but very effective operation for posterior quadrantic epilepsy. Good epileptologic outcomes require not only that the epileptogenic lesion does not extend beyond the confines of the disconnected cerebral volume but also the absence of subtle MRI abnormalities, more widespread than the clear-cut lesion of the posterior quadrant. Hemispheric or contralateral (particularly frontal) propagation of the epileptic activity may also indicate the presence of a hemispheric rather than posterior quadrantic pathology.

Neurosurgical approaches to pediatric epilepsy: Indications, techniques, and outcomes of common surgical procedures

Epilepsy is a common pediatric neurological condition, and approximately one-third of children with epilepsy are refractory to medical management. For these children neurosurgery may be indicated, but operative success is dependent on complete delineation of the epileptogenic zone. In this review, surgical techniques for pediatric epilepsy are considered. First, potentially-curative operations are discussed and broadly divided into resections and disconnections. Then, two palliative approaches to seizure control are reviewed. Finally, future neurosurgical approaches to epilepsy are considered.

Periinsular anterior quadrantotomy: technical note

Refractory frontal lobe epilepsy has been traditionally treated through a frontal lobectomy. A disconnective technique may allow similar seizure outcomes while avoiding the complications associated with large brain resections. The aim of this study was to describe a new technique of selective disconnection of the frontal lobe that can be performed in cases of refractory epilepsy due to epileptogenic foci involving 1 frontal lobe (anterior to the motor cortex), with preservation of motor function. In addition to the description of the technique, an illustrative case is also presented. This disconnective procedure is divided into 4 steps: the suprainsular window, the anterior callosotomy, the intrafrontal disconnection, and the frontobasal disconnection. The functional neuroanatomy is analyzed in detail for each step of the surgery. It is important to perform cortical and subcortical electrophysiological mapping to guide this disconnective procedure and identify eloquent cortices and intact neural pathways. The authors describe the case of a 9-year-old boy who presented with refractory epilepsy due to epileptogenic foci localized to the right frontal lobe. MRI confirmed the presence of a focal cortical dysplasia of the right frontal lobe. A periinsular anterior quadrant disconnection (quadrantotomy) was performed. The postoperative period was uneventful, and the patient was in Engel seizure outcome Class I at the 3-year follow-up. A significant cognitive gain was observed during follow-up. Periinsular anterior quadrantotomy may thus represent a safe technique to efficiently treat refractory epilepsy when epileptogenic foci are localized to 1 frontal lobe while preserving residual motor functions.

Utility of Stereoelectroencephalography in Children with Dysembryoplastic Neuroepithelial Tumor and Cortical Malformation

BACKGROUND

Uncontrolled seizures in children can contribute to irreversible cognitive impairment and developmental delay, in addition to placing them at risk for sudden unexplained death in epileptic patients (SUDEP). Since its introduction at Saint Ann Hospital in Paris in the 1960s, stereoelectroencephalography (SEEG) is increasingly being utilized at epilepsy centers in the United States as an invasive tool to help localize the seizure focus in drug-resistant focal epilepsy.

INDICATIONS

Children with symptomatic epilepsy, commonly due to cortical dysplasia and dysembryoplastic neuroepithelial tumor (DNET), may benefit from SEEG investigation. The arrangement of SEEG electrodes is individually tailored based on the suspected location of the epileptogenic zone (EZ). The implanted depth electrodes are used to electrically stimulate the corresponding cortices to obtain information about the topography of eloquent cortex and EZ. Morbidity: Surgical morbidity in these children undergoing SEEG investigation is low, but not negligible. The number of electrodes directly correlates with the risk of intraoperative complication. Thus a risk and benefit analysis needs to be carefully considered for each patient. Neurodiagnostic technology: Both during and after the SEEG electrode implantation, the intraoperative monitoring and EEG technologists play a vital role in the successful monitoring of the patient.

CONCLUSION

SEEG is an important tool in the process of epilepsy surgery in children with symptomatic epilepsy, commonly due to cortical dysplasia and DNET.

Tailored disconnection based on presurgical evidence in catastrophic epilepsy: report of 2 cases

Catastrophic epilepsy in infants, often due to extensive cortical dysplasia, has devastating consequences with respect to brain development. Conventional lobar, multilobar, or hemispheric resection in these infants is challenging, carrying an increased operative risk compared with that in older children. Removing a larger tissue volume versus removing or disconnecting the epileptogenic region does not always guarantee better seizure outcome. The authors describe 2 infants with catastrophic epilepsy who benefited from individually tailored disconnections based on a hypothesized epileptogenic zone following intensive presurgical evaluation. Two infants with catastrophic epilepsy and epileptic spasms underwent leukotomies between 3 and 12 months of age. They were followed up postoperatively for 19-36 months. Both patients had 90%-100% seizure reduction and a significantly improved neurodevelopmental outcome without postoperative complication. Cortical malformation was seen in both patients. Modifications of established surgical disconnection techniques, tailored to each patient's specific epileptogenic zone, optimized seizure and neurodevelopmental outcomes while minimizing the risks associated with more extensive resections.

Treatment of Focal Status Epilepticus plus Epileptic Spasms with Leukotomy in an Infant with TSC 1 Mutation: A Case Study

BACKGROUND

Focal status epilepticus and catastrophic epilepsy are not rare in infants. Epilepsy surgery can be safely done in selected infants to cure epilepsy.

PATIENT DESCRIPTION

We report on an infant who began having drug-resistant status epilepticus at 2 weeks of age and developed epileptic spasms. We discuss in detail how the clinical and electroencephalographic data were used to reach a consensus for epilepsy surgery and why a particular surgical approach was preferred over other alternatives.

METHOD

Presurgical evaluation consisted of 32-channel scalp video EEG using the standard 10-20 system of electrodes, 3-Tesla brain magnetic resonance imaging, and 18 F-fluorodeoxyglucose positron emission tomography. The surgery consisted of resection of the extensive epileptogenic lesion, in addition to disconnection of the left frontal lobe anterior to the motor strip.

RESULT

The infant underwent epilepsy surgery at three months of age. At two-year follow up, she remained seizure free, with no focal motor deficit and the epileptic encephalopathy resolved. The disconnected left frontal lobe shows epileptiform discharges restricted to the disconnected tissue.

CONCLUSION

We highlight the importance of epilepsy surgery in selected infants to achieve seizure freedom and to reverse epileptic encephalopathy. In the process, we demonstrate how epileptic spasms, although clinically and electrographically generalized, resolved after disconnecting the epileptogenic zone.

Surgery for posterior quadrantic cortical dysplasia. A review

BACKGROUND

Posterior quadrant dysplastic lesions represent 3-15 % of multilobar cortical developmental pathologies, 3-5 % of all the indications to surgery for epilepsy resistant to medical treatment.

OBJECTIVE AND METHODS

The objective of this study is to review the pertinent literature related to the presurgical clinical, neurophysiological, and neuroradiological evaluation of children affected by posterior quadrant dysplasia in order to discuss the intraoperative management and the different surgical techniques that have been proposed to treat this condition as well as factors related with postsurgical seizure outcome.

RESULTS AND CONCLUSIONS

Seizures appear most commonly in infants and rapidly progress to a catastrophic course. They are mostly represented by focal seizures and spasms. Surface interictal video-EEG is characterized by background flattening and paroxysmal discharges prevalent on the affected side but not unusually extending to the controlateral hemisphere. The last occasionally shows an independent irritative activity in spite of the absence of further visible structural abnormalities. Most of the patients have visual field or visual attention deficits at diagnosis. Resective as well as disconnective surgical procedures have been proposed for the management of this condition, none of them having shown clear advantages in terms of seizure outcome and complications. Intraoperative electrocorticography (EcoG) and sensorimotor monitoring have been successfully used to improve the localization of the epileptic focus and reduce surgical complication rates. Undistincted lesion borders, independent controlateral ictal or/and interictal EEG activity, and incomplete resections/disconnections are among the main factors that have resulted to be associated with a worse seizure outcome.

Posterior disconnection in early infancy to treat intractable epilepsy with multilobar cortical dysplasia: three case report

Extensive multilobar cortical dysplasias occasionally occur in children and can induce seizure onset in early infancy, causing severe epileptic encephalopathy. Surgical interventions in early infancy, such as disconnection of large parts of the brain, are challenging because of the degree of invasiveness and carry greater risks in infants compared with older children. Here we report the successful treatment of intractable epilepsy with multilobar cortical dysplasias in the posterior cortex by posterior disconnection in three infants (age 3 months). The patients showed good postoperative recovery and exhibited excellent seizure control at follow-up evaluation within a year after surgery. Developmental catch-up was also achieved and no early complications have been detected to date. Use of the posterior disconnection technique for early-stage extensive multilobar cortical dysplasias can result in good seizure control and developmental progress with little perioperative morbidity. However, the efficacy of this surgical technique needs to be verified with long-term follow up after surgery.

Epilepsy surgery for early infantile epileptic encephalopathy (ohtahara syndrome)

Early infantile epileptic encephalopathy or Ohtahara syndrome is the earliest form of the age-dependent epileptic encephalopathies. Its manifestations include tonic spasms, focal motor seizures, suppression burst pattern, pharmaco-resistance, and dismal prognosis. The purpose of this study was to evaluate the effectiveness of epilepsy surgery in selected infants. We identified 11 patients, 9 from the literature and 2 from our institution that fulfilled diagnostic criteria of Ohtahara syndrome and had undergone epilepsy surgery in infancy. Seven of the 11 infants have remained seizure free (Engel class IA) and four are reportedly having rare to infrequent seizures (Engel class IIB). All patients experienced "catch up" development. In contrast to Ohtahara's15 pharmacotherapy managed patients, who had a mortality rate of approximately fifty percent, and those that survived continued to have seizures and were severely impaired, the outcome of selected surgically managed patients is much more favorable.

Partial disconnection procedure in a patient with bilateral lesions (case report)

PURPOSE

The method of temporal lobectomy and parietooccipital disconnection has been applied in the treatment of patients with monolateral widespread cortical lesions and with hand motor function intact. There are no data regarding the use of this method in the treatment of patients with bilateral lesions.

CASE REPORT

A case history of a 15-year-old female patient with medically refractory epilepsy is presented. Magnetic resonance imaging revealed bilateral periventricular nodular heterotopia associated with cortical dysplasia (CD) in the right temporo-parietal region. The left hemisphere had no signs of CD. Invasive monitoring revealed rhythmic theta-delta activity during the interictal period and fast activity during the ictal onset in the right temporal and parietal regions. The surgery procedure consisted of anterior temporal lobectomy, the removal of the right heterotopy nodus, the dissection of the posterior part of the corpus callosum, and the detachment of the temporo-parieto-occipital complex by dissection behind the sensorimotor cortex. Histological examination of the cortex revealed CD type I. The patient has been seizure-free for 4 years after surgery.

CONCLUSION

Partial disconnection procedures may be effective in cases where total hemispherotomy is not indicated in patients with bilateral lesions and a well-lateralized epileptogenic zone localized in the temporo-parieto-occipital region.

Long-term developmental outcome in patients with West syndrome after epilepsy surgery

It has been hypothesized that early seizure control may prevent children with intractable epileptic spasms (ES) from developmental regression and may contribute to better developmental outcome. The effectiveness of surgery for ES has been reported. We investigated long-term post-operative outcomes of seizure control and development in patients with symptomatic West syndrome (S-WS) who underwent epilepsy surgery. Six children who underwent surgical intervention for intractable ES were retrospectively investigated. Cortical malformations were observed on pre-operative MRI in all patients, with hemispheric or multilobar involvement in four children and focal lesions in two. Following surgery, we measured motor function, developmental age (DA), language skills, and sociopsychological function for up to 7years (mean, 4.9years). Post-operative seizure outcome was Engel Class I (n=4) or III (n=2). Motor function and DA was increased following surgery in six and five patients, respectively. Two patients started to speak in sentences following focal resection. Autistic features were noted in four of the five examined patients post-operatively. None of the patients showed developmental regression following surgery. Epilepsy surgery for S-WS with ES may result in good seizure control and improvement in motor development. Improvement in cognitive function was modest in this small cohort of children and autistic features were noted post-operatively in a substantial proportion of the children. While seizure control can be obtained by epilepsy surgery, early intervention for sociopsychological comorbidities may be warranted in children with S-WS.

Craniosynostosis following hemispherectomy in a 2.5-month-old boy with intractable epilepsy

The authors report on the case of a 6-week-old boy who presented with infantile spasms. At 2.5 months of age, the patient underwent a right hemispherectomy. Approximately 3 months postoperatively, the patient presented with left coronal craniosynostosis. Subsequent cranial vault remodeling resulted in satisfactory cosmesis. Four years after surgery, the patient remains seizure free without the need for anticonvulsant medications. The authors believe this to be the first reported case of iatrogenic craniosynostosis due to hemispherectomy, and they describe 2 potential mechanisms for its development. This case suggests that, in the surgical treatment of infants with intractable epilepsy, minimization of brain volume loss through disconnection techniques should be considered, among other factors, when determining the best course of action.

Epilepsy surgery of posterior quadrant dysplasia in the first year of life: experience of a single centre with long term follow-up

Posterior quadrant dysplasia (PQD) is a rare variant of cortical dysplasia involving the posterior regions of a single hemisphere. It is always associated with early onset, refractory epilepsy often characterized by a "catastrophic" evolution. The experience on its surgical management during the first year of life is limited to sporadic, isolated cases. Between 2002 and 2005, four children less than one-year-old and affected by drug-resistant epilepsy associated with PQD were admitted to our Institution and underwent surgical treatment. One patient remained seizure-free during all the follow-up (Engel I). The remaining three children showed a recurrence of the seizures, requiring subsequent surgical procedures in two cases. In one case (Engel II), the seizure control has been obtained thanks to pharmacological treatment. The other two patients respectively had only a partial (Engel III) and a less relevant reduction of the number of seizures (Engel IV). Both the epileptic and the neuropsychological outcome of our series were significantly influenced by persistent contralateral interictal anomalies rather than by the timing of the surgical procedure. Unpredictable results should be expected in this kind of patients if there is the detection of contralateral independent epileptiform activities on the EEG at diagnosis. Parents and relatives should be aware of the results' variability, even though a reduction of seizures may be expected, enabling an easier handling of the child's condition.

Longer duration of epilepsy and earlier age at epilepsy onset correlate with impaired cognitive development in infancy

We assessed the impact of age at onset of epilepsy and duration and frequency of seizures on cognitive development in children less than 3 years old. Retrospective analysis was conducted on clinical data and neuropsychological testing of 33 infants with epilepsy. Developmental quotients were calculated and were correlated with age at epilepsy onset, duration of epilepsy, seizure frequency, brain pathology, and types of seizures (with/without spasms) as potential predictors. Infants with longer duration and earlier onset of epilepsy performed worse on developmental neuropsychological testing. Regression analyses showed that age at epilepsy onset and percentage of life with epilepsy were both strongly associated (regression model P<0.0001) with developmental quotient. There was no correlation with seizure frequency. Infants with spasms had worse developmental quotients than infants without spasms (P<0.001). These results suggest that duration of epilepsy and age at onset may be the best developmental predictors during the first years of life in patients with epilepsy. Early aggressive intervention should be considered.

Developmental outcome after epilepsy surgery in infancy

OBJECTIVES

Our goals were to determine the effect of epilepsy surgery in infants (<3 years of age) on development and describe factors associated with postoperative developmental outcome.

METHODS

We identified 50 infants among 251 consecutive pediatric patients (<18 years old) undergoing epilepsy surgery. Charts were reviewed for clinical data and neurodevelopmental testing with the Bayley Scales of Infant Development. A developmental quotient was calculated to compare scores of children at different ages.

RESULTS

Complete data were available on 24 of 50 infants. Surgeries included 14 hemispherectomies and 10 focal resections. Seventeen patients became seizure free; 5 patients had >90% seizure reduction, 1 had >50% seizure reduction, and 1 had no change. The developmental quotient indicated modest postoperative improvement of mental age. The preoperative and postoperative development quotients correlated well. Younger infants had a higher increase in developmental quotient after surgery. Patients with epileptic spasms were younger and had a lower developmental quotient at presentation, but increase in developmental quotient was higher in this subgroup.

CONCLUSIONS

After surgery, seizure frequency and developmental quotient improved. Developmental status before surgery predicted developmental function after surgery. Patients who were operated on at younger age and with epileptic spasms showed the largest increase in developmental quotient after surgery.

Surgical treatment of two patients with infantile spasms in early infancy

Early surgery for catastrophic epilepsy may prevent developmental deterioration and minimize functional deficit resulting from the surgical procedure. We report two patients who had infantile spasms and underwent surgery for epilepsy in early infancy (younger than 6 months old). Magnetic resonance imaging showed cortical dysplasia in both patients. One patient underwent lesionectomy in the right perirolandic area at 49 weeks conceptional age (CA) and the other infant underwent left temporo-occipital disconnection at 45 weeks CA. Both showed Engel classification I and catch-up developmental progress. However, with the second patient, we were concerned about the high volume transfusion relative to her body weight during the extensive disconnection because of the patient's small blood volume. We discuss the benefits and potential risks of surgical treatment for intractable epilepsy in early infancy.