Uri Kramer’s research while affiliated with Tel Aviv University and other places

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Publications (125)


EPILEPSY SURGERY IN CHILDREN: A SUMMARY OF A DECADE AT THE SOURASKY TEL AVIV MEDICAL CENTER
  • Literature Review

April 2023

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41 Reads

Harefuah

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Itzhak Fried

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[...]

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Shimrit Uliel-Sibony

Introduction: Drug-resistant epilepsy in children is associated with morbidity, developmental regression and mortality. Over recent years, there is an increase in awareness regarding the role of surgery in the treatment of refractory epilepsy, both in the diagnostic phase and for treatment, reducing the number and magnitude of seizures. Technological advancements have enabled a minimalization of surgery, with reduction in surgical associated morbidity. Methods: In this retrospective study, we review our experience with cranial surgery for epilepsy between the years 2011-2020. Collected data included information regarding the epileptic disorder, surgery, surgical-related complications and epilepsy outcome. Results: A total of 93 children underwent 110 cranial surgeries over a decade. The main etiologies included cortical dysplasia (29), Rasmussen encephalitis (10), genetic disorders (9), tumors (7) and tuberous sclerosis (7). The main surgeries included lobectomies (32), focal resections (26), hemispherotomies (25), and callosotomies (16). Two children underwent MRI-guided laser interstitial thermal treatment (LITT). The most significant improvements following surgery were following hemispherotomy or tumor resection (100% of children, each). Following resections for cortical dysplasia led to a significant improvement in 70%. In 83% of children undergoing callosotomy, there were no additional drop seizures; 14% of the entire group underwent additional epilepsy surgery; 23% of children had an unexpected complication, in the vast majority with no permanent sequela. There was not mortality. Conclusions: Epilepsy surgery may lead to significant improvement and even cure of epilepsy. There is a wide span of epilepsy surgical procedures. Ealy referral of children with refractory epilepsy for surgical evaluation may significantly reduce the developmental injury, and improve functional outcomes.


Fig. 1 The study population of 117 patients with West syndrome classified according to treatment regimen (ACTH and no ACTH therapy) and the revised International League Against Epilepsy classification. No patients were classified as being in the "metabolic etiology" group. Unknown etiology is subcategorized as with or without psychomotor developmental delay
Stacked column charts of the categorical representation of weight status (a), systolic (b) and diastolic (c) blood pressure, TG levels (d), HDL-c levels (e) and triglyceride to HDL-c ratios in patients with West syndrome during infancy, early childhood, and childhood/adolescence. The proportion of patients with cardiometabolic derangements was higher in infancy compared to childhood/adolescence (obesity P = 0.010, diastolic hypertension P < 0.001, hypertriglyceridemia P = 0.008, low HDL-c levels P = 0.001, elevated TG/HDL-c ratios P < 0.001). Abbreviations: TG triglycerides; HDL-c high-density lipoprotein cholesterol
Cardiometabolic outcomes in children and adolescents with West syndrome
  • Article
  • Full-text available

September 2021

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55 Reads

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2 Citations

BMC Pediatrics

Abstract Background West syndrome is a convulsive disorder of infancy with unique seizures and a characteristic background electroencephalograph pattern. Adrenocorticotropic hormone (ACTH) is effective in spasm cessation, yet metabolic consequences of this therapeutic agent in childhood have not been published. Methods In this observational study we explored the cardiometabolic outcomes of 117 children with West syndrome (78 ACTH-treated and 39 non-ACTH-treated) monitored at a single medical center from 1995 to 2019 (median follow-up 7.2 years). Outcomes included the prevalence of cardiometabolic derangements (obesity, hypertension, and dyslipidemia) during infancy (

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Early prediction of encephalopathic transformation in children with benign epilepsy with centro-temporal spikes

September 2020

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34 Reads

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8 Citations

Brain and Development

Background: Most children with Benign epilepsy with centro-temporal spikes (BECTS) undergo remission during late adolescence and do not require treatment. In a small group of patients, the condition may evolve to encephalopathic syndromes including epileptic encephalopathy with continuous spike-and-wave during sleep (ECSWS), or Landau-Kleffner Syndrome (LKS). Development of prediction models for early identification of at-risk children is of utmost importance. Aim: To develop a predictive model of encephalopathic transformation using data-driven approaches, reveal complex interactions to identify potential risk factors. Methods: Data were collected from a cohort of 91 patients diagnosed with BECTS treated between the years 2005-2017 at a pediatric neurology institute. Data on the initial presentation was collected based on a novel BECTS ontology and used to discover potential risk factors and to build a predictive model. Statistical and machine learning methods were compared. Results: A subgroup of 18 children had encephalopathic transformation. The least absolute shrinkage and selection operator (LASSO) regression Model with Elastic Net was able to successfully detect children with ECSWS or LKS. Sensitivity and specificity were 0.83 and 0.44. The most notable risk factors were fronto-temporal and temporo-parietal localization of epileptic foci, semiology of seizure involving dysarthria or somatosensory auras. Conclusion: Novel prediction model for early identification of patients with BECTS at risk for ECSWS or LKS. This model can be used as a screening tool and assist physicians to consider special management for children predicted at high-risk. Clinical application of machine learning methods opens new frontiers of personalized patient care and treatment.


Candidate variants in FIRES.
Whole‐exome and HLA sequencing in Febrile infection‐related epilepsy syndrome

July 2020

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157 Reads

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21 Citations

Febrile infection‐related epilepsy syndrome (FIRES) is a devastating epilepsy characterized by new‐onset refractory status epilepticus with a prior febrile infection. We performed exome sequencing in 50 individuals with FIRES, including 27 patient–parent trios and 23 single probands, none of whom had pathogenic variants in established genes for epilepsies or neurodevelopmental disorders. We also performed HLA sequencing in 29 individuals with FIRES and 529 controls, which failed to identify prominent HLA alleles. The genetic architecture of FIRES is substantially different from other developmental and epileptic encephalopathies, and the underlying etiology remains elusive, requiring novel approaches to identify the underlying causative factors.


Cannabidiol-enriched oil in children and adults with treatment-resistant epilepsy-does tolerance exist?

July 2020

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55 Reads

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32 Citations

Brain and Development

Aim To evaluate the long-term effectiveness of cannabidiol (CBD)-enriched oil for the treatment of refractory epilepsy and to assess the development of tolerance to its anti-seizure effect. Methods A prospective study of 92 consecutive patients (age 1–37 years, mean-11.8 years) with treatment resistant epilepsy who were treated with cannabis oil extract (CBD/tetrahydrocannabinol [THC] ratio of 20:1). Mean monthly seizure frequency was reported by the patients/their parents during monthly clinic visits. Tolerance was defined as either the need to increase the dose by ≥30% due to reduced treatment efficacy or as an increase of ≥30% in mean monthly seizure frequency in patients treated for at least 3 months with no change in other anti-seizure medications. Results Mean follow-up time was 19.8 ± 12.5 months (range 3–45). Mean CBD dose was 11.3 (4–38) mg/kg/day. Twenty-nine (31%) patients discontinued treatment due to lack of effect or adverse reactions, which were reported in 51% (47/87) of the patients. Overall responder rate (>50% seizures reduction) was 54%, whereas 8 patients (9%) became seizure-free. Eighty-four patients were included in the tolerance analysis. Tolerance was observed in 21 (25%) patients after a mean duration of 7.3 ± 5.4 months of CBD-enriched oil treatment. There was a negative correlation between epilepsy duration and tolerance development (p = 0.038). Conclusions We report for the first time the plausible appearance of tolerance to cannabidiol-enriched oil. This may limit treatment efficacy in the long-term clinical management of refractory epilepsy in both pediatric and adult population. Further studies are needed to investigate potential mechanisms.


Number of responders by treatment period.
LSmean seizure count -change and percent change from baseline.
Seizure count -percent change from baseline. Subject # Seizure count (% change from observation period)
Treatment-related a adverse events.
The safety, tolerability, and effectiveness of PTL-101, an oral cannabidiol formulation, in pediatric intractable epilepsy: A phase II, open-label, single-center study

September 2019

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209 Reads

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43 Citations

Epilepsy & Behavior

Introduction Several works have reported on the antiepileptic impact of cannabis-based preparations in patients with treatment-resistant epilepsy (TRE). However, current formulations suffer from low bioavailability and side effects. PTL-101, an oral formulation containing highly purified cannabidiol (CBD) embedded in seamless gelatin matrix beadlets was designed to enhance bioavailability and maintain a constant gastrointestinal transit time. Methods This phase II, prospective study was open to pediatric patients with TRE on stable antiepileptic drugs' (AEDs) doses, who experienced ≥ 4 seizures within four weeks of enrolment and with a history of ≥ 4 AEDs failing to provide seizure control. Following a 4-week observation period, patients began a 2-week dose-titration phase (up to ≤ 25 mg/kg or 450 mg, the lower of the two), followed by a 10-week maintenance treatment period. Caregivers recorded seizure frequency, type, and severity and ranked their global impressions after 7 and 12 weeks of treatment. Responders were those showing a ≥ 50% reduction from baseline monthly seizure frequency. Safety assessments monitored vital signs, adverse effects, physical and neurological exams, and laboratory tests. Results Sixteen patients (age: 9.1 ± 3.4) enrolled in the study; 11 completed the full treatment program. The average maintenance dose was 13.6 ± 4.2 mg/kg. Patient adherence to treatment regimens was 96.3 ± 9.9%. By the end of the treatment period, 81.9% and 73.4 ± 24.6% (p < 0.05) reductions from baseline median seizure count and monthly seizure frequency, respectively, were recorded. Responders' rate was 56%; two patients became fully seizure-free. By study end, 8 (73%) caregivers reported an improved/very much improved condition, and 9 (82%) reported reduced/very much reduced seizure severity. Most commonly reported treatment-related adverse effects were sleep disturbance/insomnia, (4 (25.0%) patients), followed by somnolence, increased seizure frequency, and restlessness (3 patients each (18.8%)). None were serious or severe, and all resolved. Conclusions PTL-101 was safe and tolerable for use and demonstrated a potent seizure-reducing effect among pediatric patients with TRE.


Development of Ontology for Self-limited Epilepsy with Centrotemporal Spikes and Application of Data Mining Algorithms to Identify New Subtypes

July 2019

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20 Reads

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3 Citations

The Israel Medical Association journal

Background: Benign rolandic epilepsy or benign childhood epilepsy with centrotemporal spikes (BCECTS) is a common childhood epileptic syndrome. The syndrome resolves in adolescence, but 1-7% of patients have an atypical presentation, some of which require aggressive medical treatment. Early treatment may prevent complications and neurocognitive deterioration. Variants include Landau-Kleffner syndrome (LKS) and electrical status epilepticus during sleep (ESES). Objectives: To determine data driven identification of risk factors and characterization of new subtypes of BCECTS based on anontology. To use data mining analysis and correlation between the identified groups and known clinical variants. Methods: We conducted a retrospective cohort study comprised of 104 patients with a diagnosis of BCECTS and a minimum of 2 years of follow-up, between the years 2005 and 2017. The medical records were obtained from the epilepsy service unit of the pediatric neurology department at Dana-Dwek Hospital, Tel Aviv Sourasky Medical Center. We developed a BCECTS ontology and performed data preprocessing and analysis using the R Project for Statistical Computing (https://www.r-project.org/) and machine learning tools to identify risk factors and characterize subgroups. Results: The ontology created a uniform and understandable infrastructure for research. With the ontology, a more precise characterization of clinical symptoms and EEG activity of BCECTS was possible. Risk factors for the development of severe atypical presentations were identified: electroencephalography (EEG) with spike wave (P < 0.05), EEG without evidence of left lateralization (P < 0.05), and EEG localization (centrotemporal, frontal, or frontotemporal) (P < 0.01). Conclusions: Future use of the ontology infrastructure for expanding characterization for multicenter studies as well as future studies of the disease are needed. Identifying subgroups and adapting them to known clinical variants will enable identification of risk factors, improve prediction of disease progression, and facilitate adaptation of more accurate therapy. Early identification and frequent follow-up may have a significant impact on the prognosis of the atypical variants.



Citations (87)


... An early seizure detection method for WEST syndrome based on cardiac autonomic regulation dynamics has been developed in [9]. It is recently shown that [10] WEST syndrome subjects apparently have an increased prevalence of cardio metabolic derangement. Although fruitful results have been done on ECG based epilepsy analysis, most are using heart rate variability (HRV). ...

Reference:

Deterministic Learning based WEST Syndrome Analysis and Seizure Detection on ECG
Cardiometabolic outcomes in children and adolescents with West syndrome

BMC Pediatrics

... Given the poor neurocognitive outcomes associated with EE-SWAS, there is an urgent need for early predictors to indicate the emergence of EE-SWAS. Recent studies have attempted to address this issue, but due to limitations in indicator selection and sample size, no successful models have yet been developed [36][37][38]. General clinical features lack effective predictive value for the encephalopathic transformation of SeLECTS. ...

Early prediction of encephalopathic transformation in children with benign epilepsy with centro-temporal spikes
  • Citing Article
  • September 2020

Brain and Development

... Given the context that most patients (77.61%) were current or ex-users, which is larger than the hypothesized lifetime prevalence in people with epilepsy of between 10-40%, this may have contributed to the positive results observed (Beers et al. 2023). Conversely, these individuals may have already developed pharmacological tolerance to cannabis, limiting the effect CBMPs may have (Uliel-Sibony et al. 2021). Furthermore, there is a greater prevalence of men (67.9%) than women within the study, despite women being more likely to develop TRE (Cepeda et al. 2022). ...

Cannabidiol-enriched oil in children and adults with treatment-resistant epilepsy-does tolerance exist?
  • Citing Article
  • July 2020

Brain and Development

... Additionally, although these findings will most likely motivate a new era of research into autoimmune causes of NORSE and FIRES, it is important to keep in mind the unsuccessful efforts that have already been spent trying to identify such causes, including the lack of an HLA signature in FIRES. 9 In addition, PRSs are not iron-clad-they depend on many assumptions and arbitrary cutoffs, further emphasizing the need for replication rather than taking the findings by Jang et al 6 as ground truth. ...

Whole‐exome and HLA sequencing in Febrile infection‐related epilepsy syndrome

... Porat Rein et al. carried out a retrospective cohort study involving 104 cases with BECTS. They identified the following risk factors for the development in these patients of severe atypical variants including LKS and ESES: EEG spike-waves; EEG without evidence of left lateralization; and centro-temporal, frontal, or fronto-temporal EEG localization [67]. Subsequently, Porat Rein et al. developed a predictive model of transformation of BECTS into epileptic encephalopathy with CSWS or LKS collecting data from a cohort of 91 BECTS cases, of which 18 showed an encephalopathic transformation. ...

Development of Ontology for Self-limited Epilepsy with Centrotemporal Spikes and Application of Data Mining Algorithms to Identify New Subtypes
  • Citing Article
  • July 2019

The Israel Medical Association journal

... 32 Regarding the risk of bias assessment, among the five randomized intervention studies, four were scored as low risk 18,19,25,29 and one with some concern. 38 For the 10 uncontrolled before-after studies, 4 were scored as good, 16,26,28,31 5 were fair, 17,22,23,30 and 1 was poor. 21 Of the nine observational retrospective case series, two were scored as good, 13-34 six were fair, 14,20,27,33,36,37 and one was poor. ...

The safety, tolerability, and effectiveness of PTL-101, an oral cannabidiol formulation, in pediatric intractable epilepsy: A phase II, open-label, single-center study

Epilepsy & Behavior

... The vast interconnected network involved in higher-order perceptions such as memory and speech proposes another challenge when evoking perceptions through invasive stimulation techniques. Stimulation studies suggest that speech and higherorder cognitive perceptions involve the activation of widely distributed neural networks (Sanai et al., 2008;Elliott et al., 2009;Selimbeyoglu and Parvizi, 2010;Andelman-Gur et al., 2019). Various perceptions of mnemonic, affective, and speech content were evoked in the occipital and temporal lobes and also the frontal lobe during invasive stimulation (Gloor, 1990;Elliott et al., 2009;Selimbeyoglu and Parvizi, 2010;Andelman-Gur et al., 2019). ...

Spatial distribution and hemispheric asymmetry of electrically evoked experiential phenomena in the human brain

Journal of Neurosurgery

... 8 Previous studies regarding the efficacy of VNS in reducing seizure frequency amongst patients with intractable epilepsy have demonstrated somewhat inconsistent results, with some exhibiting significant reductions, while the others displaying insignificant reductions or adverse outcomes. [14][15][16] Conflicting results regarding VNS implantation and the requirement of AEDs were also noted. Such gaps between these results led to the necessity to further evaluate the effects and efficacy of VNS towards seizure reduction in intractable epilepsy. ...

Improved quality of life and cognition after early vagal nerve stimulator implantation in children
  • Citing Article
  • September 2018

Epilepsy & Behavior

... En cuanto a la posología, la literatura refiere una dosis de inicio de CBD variable (0,018 -5 mg/kg/día) (25)(26)(27)(28)(29) . En el trabajo publicado por Devinsky y colaboradores en 2017, que incluyó 120 sujetos entre 2-18 años con SD, la dosis de inicio de CBD (Epidiolex 10% ® ) fue 5 mg/kg/día titulando luego a 20 mg/kg/ día (4) . ...

Efficacy of CBD-enriched medical cannabis for treatment of refractory epilepsy in children and adolescents – An observational, longitudinal study
  • Citing Article
  • April 2018

Brain and Development

... In 2014, Schen et al. used WES to describe a SNAP25B de novo pathogenic variant in one affected child [p.Ile67Asn (c.200T.A)], resulting in an inhibition of synaptic vesicle exocytosis [43]. Moreover, in 2018, a novel missense SNAP25 variant [p.Arg59Pro (c.176G>C)] inherited from the mosaic father was described by Fukuda et al. in two affected siblings (a female and a male) showing seizures and motor clumsiness; the female also presented delayed speech, cerebellar ataxia, hypotonia, learning disabilities, and ADHD [42]. Interestingly, Klöckner et al. [41] described 23 individuals with 19 de novo variants in SNAP25 (15 different missense variants, four loss of function variants, two nonsense, and two splice donor variants). ...

A novel missense SNAP25b mutation in two affected siblings from an Israeli family showing seizures and cerebellar ataxia
  • Citing Article
  • February 2018

Journal of Human Genetics