In the US, >20% of individuals aged 5 years and older speak a language other than English at home, with rates of bi- and multilingualism increasing. Providing linguistically- and culturally- competent care to increasingly diverse populations is a necessary task for neuropsychologists. The need for close attention to bilingualism is even more glaring in the context of neurosurgical interventions, such as in intractable epilepsy. Pre-surgical epilepsy evaluations serve as a baseline for post-surgical change, inform lateralization and localization, and help determine cognitive risks associated with surgery. The importance of evaluating bilingual status and assessing cognitive abilities in both languages, if needed, in presurgical epilepsy evaluations is examined. We present the neuropsychological profile of a 10-year-old bilingual male with intractable epilepsy participating in a pre-surgical epilepsy evaluation.

This right-handed male is a sequential language learner, exposed to Spanish at birth and English when he began kindergarten. His parent reported he was primarily English speaking. Developmental milestones were met within expected timeframes. Seizures began at age 5. He is prescribed Vimpat and Lamictal. vEEG during admission revealed right temporal-onset seizures. Neuropsychological assessment was conducted in English based on parent report; however, expressive language testing revealed significantly higher performance in Spanish (average) compared to English (exceptionally low). Subsequently, a bilingual provider was consulted, and supplemental Spanish verbal reasoning and verbal memory measures were administered.

The patient’s neuropsychological profile captured a significant difference between English and Spanish verbal abilities. WISC-V Similarities scaled scores (ss) were 5 and 11 in English and Spanish, respectively. Vocabulary scaled scores were 8 and 15 in English and Spanish, respectively. Regarding verbal memory, list learning was below average in English (ss = 5), but low average in Spanish (ss = 6). Contextual verbal memory was only administered in Spanish; scores were average (ss = 10). Verbal Fluency administered in English was low (phonemic fluency ss = 5, categorical fluency ss = 6). fMRI verbal tasks were performed in English and revealed left-sided language lateralization.

In pre-surgical epilepsy evaluations of bilingual children, consideration of language is essential. Assessment of language dominance is a minimum requirement in bilingual families, followed by full bilingual evaluation if necessary. In this case, starkly different conclusions regarding lateralization and localization may have been made if the child had not been evaluated in both languages. In English, a significant split between verbal and non-verbal cognition was apparent, possibly suggesting involvement of the dominant left hemisphere. With Spanish testing, this split disappeared, with high average verbal skills. While a growing proportion of children in the US are bilingual, bilingual assessments are not commonly conducted in pre-surgical epilepsy evaluations. In fact, very little work has been done examining language functioning in bilingual epilepsy patients, particularly in children. With both epilepsy-and language-related factors at play in a developing brain, we encourage closer attention to these issues, particularly in the context of neurosurgical procedures.

Anterior temporal lobectomy is a common surgical approach for medication-resistant temporal lobe epilepsy (TLE). Prior studies have shown inconsistent findings regarding the utility of presurgical intracarotid sodium amobarbital testing (IAT; also known as Wada test) and neuroimaging in predicting postoperative seizure control. In the present study, we evaluated the predictive utility of IAT, as well as structural magnetic resonance imaging (MRI) and positron emission tomography (PET), on long-term (3-years) seizure outcome following surgery for TLE.

Patients consisted of 107 adults (mean age=38.6, SD=12.2; mean education=13.3 years, SD=2.0; female=47.7%; White=100%) with TLE (mean epilepsy duration =23.0 years, SD=15.7; left TLE surgery=50.5%). We examined whether demographic, clinical (side of resection, resection type [selective vs. non-selective], hemisphere of language dominance, epilepsy duration), and presurgical studies (normal vs. abnormal MRI, normal vs. abnormal PET, correctly lateralizing vs. incorrectly lateralizing IAT) were associated with absolute (cross-sectional) seizure outcome (i.e., freedom vs. recurrence) with a series of chi-squared and t-tests. Additionally, we determined whether presurgical evaluations predicted time to seizure recurrence (longitudinal outcome) over a three-year period with univariate Cox regression models, and we compared survival curves with Mantel-Cox (log rank) tests.

Demographic and clinical variables (including type [selective vs. whole lobectomy] and side of resection) were not associated with seizure outcome. No associations were found among the presurgical variables. Presurgical MRI was not associated with cross-sectional (OR=1.5, p=.557, 95% CI=0.4-5.7) or longitudinal (HR=1.2, p=.641, 95% CI=0.4-3.9) seizure outcome. Normal PET scan (OR= 4.8, p=.045, 95% CI=1.0-24.3) and IAT incorrectly lateralizing to seizure focus (OR=3.9, p=.018, 95% CI=1.2-12.9) were associated with higher odds of seizure recurrence. Furthermore, normal PET scan (HR=3.6, p=.028, 95% CI =1.0-13.5) and incorrectly lateralized IAT (HR= 2.8, p=.012, 95% CI=1.2-7.0) were presurgical predictors of earlier seizure recurrence within three years of TLE surgery. Log rank tests indicated that survival functions were significantly different between patients with normal vs. abnormal PET and incorrectly vs. correctly lateralizing IAT such that these had seizure relapse five and seven months earlier on average (respectively).

Presurgical normal PET scan and incorrectly lateralizing IAT were associated with increased risk of post-surgical seizure recurrence and shorter time-to-seizure relapse.

Periventricular nodular heterotopia (PVNH) is a malformation of cortical development (MCD) characterized by aggregates of gray matter adjacent to the lateral ventricular walls. Clinical presentation is heterogeneous with higher rates of seizures and reading impairments typically in the setting of average IQ (Felker et al. 2011). The majority of neuropsychological inquiry has focused on reading fluency, though a single case study showed a neurocognitive profile consistent with nonverbal learning deficits in a 7-year old boy with suspected autosomal dominant bilateral heterotopia (McCann et al., 2008). Given the periventricular focus and potential for unilateral presentations, non-linguistic neurocognitive sequelae may be expected in cases affecting the non-dominant hemisphere, yet this remains largely unexplored. Surgical ablation by laser interstitial thermal therapy (LITT) is increasingly used for epilepsy management in PVNH (Thompson et al., 2016, Whiting et al. 2020). However, there are no reported studies exploring cognitive outcomes following LITT of focal PVNH.

A 46-year-old, right handed, Black female with 16 years of education presented for management of medically refractory epilepsy. Epilepsy monitoring captured intermittent slow waves in the right temporal lobe, interictal polyspikes in the right temporal lobe, and three epileptic events all emanating from the right temporal lobe. MRI showed extensive migrational anomalies involving the right hemisphere posteriorly consistent with PVNH with no associated mesial temporal sclerosis. Pre-surgical neuropsychological evaluation showed a significant split in IQ, with verbal IQ = 99 and performance IQ = 76. Testing indicated circumscribed deficits in visuoperceptual judgement, visuoconstruction, visuospatial reasoning, non-verbal recall, and several executive weaknesses in the context of otherwise average neurocognitive functioning. Fine motor speed was impaired bilaterally. Her profile was suggestive of non-dominant fronto-parieto-temporal dysfunction, concordant with the remainder of her work-up. By history she reported longstanding academic weaknesses in math and organization with strong verbal and reading abilities.

The patient underwent partial LITT of right PVNH sparing areas involved in visual function. At 6-month follow-up she was seizure free (Engel outcome 1A). Post-surgical neuropsychological evaluation showed reliable improvements in perceptual reasoning, aspects of learning/memory, and verbal naming. Visuoconstruction remained impaired but qualitatively improved. She also reported subjective experience of improved mental clarity and was applying for jobs after regaining driving privileges.

This case demonstrates symptoms and history concerning for a nonverbal learning disorder in an adult woman with epilepsy secondary to right hemisphere PVNH and underscores the importance of exploring the range of neurocognitive profiles in MCD. Her notable neurocognitive and functional improvements following surgical ablation and seizure freedom suggest a possible release of function in the absence of inhibitory neurophysiological influences. This raises interesting questions about the endurance of her developmental profile. This case report contributes to our understanding of neuroanatomical correlates of neurocognitive and neurodevelopmental presentations. Future investigations should explore neuropsychological changes following LITT for PVNH.

Poor mood and quality of life is common among patients with medically intractable seizures. Many of these patients are not candidates for seizure focus resection and continue to receive standard medical care. Responsive neurostimulation (RNS) has been an effective approach to reduce seizure frequency for nonsurgical candidates. Previous research using RNS clinical trial participants has demonstrated improved mood and quality of life when patients received RNS-implantation earlier in their medically resistant epilepsy work-up (Loring et al., 2021). We aimed to describe the level of depression and quality of life in adults with medical resistant epilepsy, treated with RNS, presenting to an outpatient clinic.

This pilot study was conducted among 11 adult epilepsy patients treated with RNS at the epilepsy specialty clinic at Baylor College of Medicine. Ages of participants ranged from 18-56 (M=32.01, SD=12.37) with a mean education of 12.43 (SD=0.85). The majority of the participants identified as White (White=72.2%; Hispanic/Latino/a=14.3%, Other=7.1%). We also present pre- and post-RNS preliminary results of a subset of 4 patients for whom pre and post implantation data was available. Depression symptoms were assessed through the Beck Depression Inventory, 2nd Edition (BDI-II) and quality of life was determined using the Quality of Life in Epilepsy (QoLiE-31).

Patients reported minimal symptoms of depression (M=5.45, SD=4.03) and good overall quality of life (M=71.18, SD=14.83) after RNS. Participants’ scores on their overall quality of life ranged from 50 to 95 (100=better quality of life). The QoLiE-31 showed high scores on emotional wellbeing (M=69.45, SD=14.56) and cognitive functioning (M=65.36, SD=16.66) domains. Post-hoc analysis revealed a significant difference in the cognitive functioning domain of QoLiE-31 before (M=44.75, SD=12.58) and after (M=51.0, SD=11.58) RNS implantation(t(3)=-3.78, p=0.016. Additionally, overall QoLiE score approached statistical significance when comparing pre-RNS (M=44.75 SD=9.29) to post-RNS (M=49.75 SD=11.62; t(3)=-2.01, p = 0.069). No significant differences were evident on seizure worry, energy/fatigue, medication effects, and social functioning domains of QoLiE-31 before and after RNS treatment.

These pilot study results suggest low levels of depression with this population post-RNS implantation. Additionally, there is preliminary evidence to suggest improved patient-rated cognitive functioning and overall quality of life. While this is a small study population, the results have important implications for patients with intractable epilepsy, even with those form who surgical resection may not be possible. Future studies with large enough samples to examine moderating and mediating factors to mood and quality of life changes post-RNS will be important.

Many epilepsy syndromes are medically refractory, leading patients to be referred for surgical work-up to control their seizures and improve their quality of life (QOL). Although surgical treatments may reduce or stop seizures, many patients continue to present with declines in mood and/or cognition post-operatively. In addition, pre-operative QOL of patients with medically refractory epilepsy is impacted by executive function (EF). The present study aims to investigate the relationship between post-operative mood/QOL and pre-operative EF in adults with epilepsy. It was hypothesized that mood would remain stable or decline post-operatively; pre-operative EF would be a protective factor for mood decline and QOL.

The sample consisted of 47 adult patients (57.4% female; Age, M= 34.02(11.59)) with medically refractory epilepsy at the UCSF Epilepsy Center. Participants were included if they received surgical treatment for their epilepsy (42.6% right anterior temporal lobectomy [ATL], 46.8% left ATL, 2.1% laser ablation, 6.4% responsive neurostimulation, 2.1% multiple surgical interventions) and received both a pre- and post-surgical neuropsychological evaluation. Most patients were right-handed (95.7% right). Mood and QOL were assessed from pre- and post-operative evaluations using the Beck Depression Inventory- Second Edition (BDI-II), Beck Anxiety Inventory (BAI), and Quality of Life in Epilepsy- 31 (QOLIE-31). Executive function was assessed using the Trail Making Test, and the Delis-Kaplan Executive Function Scale (D-KEFS) subtests Color-Word Interference (CW-I) and Verbal Fluency. Descriptive statistics were obtained for each of the measures listed. A paired sample t-test was conducted between time A and B to determine whether mood and QOL were significantly different. Two multiple regressions were conducted. One analysis for post-operative depression and QOL respectively with pre-operative EF.

At time A, both anxiety and depression were minimal (BDI M= 17.8, SD= 10.34; BAI M= 13; SD= 8.94). QOL was borderline clinically significant (QOLIE M= 37.46, SD= 9.74). Depression at time B was positively correlated with depression at time A (r[45]= 0.316, p=0.035). A paired sample t-test indicated that depression and QOL were significantly different at time A and time B (t[44]= 2.04, p= 0.047; t[31]= -3.34, p= 0.002), with improved scores post-operatively. Anxiety was not significantly different across time points (t[39]= 1.20, p=0.238). Multiple regression analyses indicated that pre-operative depression and EF did not predict post-operative depression (F(5,27)= 1.62, p= 0.189). Pre-operative EF (CW-I Inhibition-Switching), but not pre-operative depression, predicted post-operative QOL (F(4(24)= 3.13, p=.03, R2= .343).

Results were somewhat discrepant from prior research in that depression and QOL improved post-surgically. Notably, while the observed change in depression was statistically significant it was not clinically significant according to literature (Doherty et al., 2021). Pre-surgical inhibitory control predicted QOL, illustrating that EF may serve as a protective factor post-surgically. The present study did not include a measure of seizure freedom classification post-operatively, therefore, future studies should investigate how seizure freedom classification impacts the relationship between mood, QOL, and cognitive outcomes.