Development of an online calculator for the prediction of seizure freedom following pediatric hemispherectomy using the Hemispherectomy Outcome Prediction Scale (HOPS)

OBJECTIVES

Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy.

METHODS

Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/).

RESULTS

The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%.

SIGNIFICANCE

Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.

Comparison of the real-world effectiveness of vertical versus lateral functional hemispherotomy techniques for pediatric drug-resistant epilepsy: A post hoc analysis of the HOPS study

Objective

This study was undertaken to determine whether the vertical parasagittal approach or the lateral peri‐insular/peri‐Sylvian approach to hemispheric surgery is the superior technique in achieving long‐term seizure freedom.

Methods

We conducted a post hoc subgroup analysis of the HOPS (Hemispheric Surgery Outcome Prediction Scale) study, an international, multicenter, retrospective cohort study that identified predictors of seizure freedom through logistic regression modeling. Only patients undergoing vertical parasagittal, lateral peri‐insular/peri‐Sylvian, or lateral trans‐Sylvian hemispherotomy were included in this post hoc analysis. Differences in seizure freedom rates were assessed using a time‐to‐event method and calculated using the Kaplan–Meier survival method.

Results

Data for 672 participants across 23 centers were collected on the specific hemispherotomy approach. Of these, 72 (10.7%) underwent vertical parasagittal hemispherotomy and 600 (89.3%) underwent lateral peri‐insular/peri‐Sylvian or trans‐Sylvian hemispherotomy. Seizure freedom was obtained in 62.4% (95% confidence interval [CI] = 53.5%–70.2%) of the entire cohort at 10‐year follow‐up. Seizure freedom was 88.8% (95% CI = 78.9%–94.3%) at 1‐year follow‐up and persisted at 85.5% (95% CI = 74.7%–92.0%) across 5‐ and 10‐year follow‐up in the vertical subgroup. In contrast, seizure freedom decreased from 89.2% (95% CI = 86.3%–91.5%) at 1‐year to 72.1% (95% CI = 66.9%–76.7%) at 5‐year to 57.2% (95% CI = 46.6%–66.4%) at 10‐year follow‐up for the lateral subgroup. Log‐rank test found that vertical hemispherotomy was associated with durable seizure‐free progression compared to the lateral approach (p = .01). Patients undergoing the lateral hemispherotomy technique had a shorter time‐to‐seizure recurrence (hazard ratio = 2.56, 95% CI = 1.08–6.04, p = .03) and increased seizure recurrence odds (odds ratio = 3.67, 95% CI = 1.05–12.86, p = .04) compared to those undergoing the vertical hemispherotomy technique.

Significance

This pilot study demonstrated more durable seizure freedom of the vertical technique compared to lateral hemispherotomy techniques. Further studies, such as prospective expertise‐based observational studies or a randomized clinical trial, are required to determine whether a vertical approach to hemispheric surgery provides superior long‐term seizure outcomes.

Hemispherectomy Outcome Prediction Scale: Development and validation of a seizure freedom prediction tool

OBJECTIVE

To develop and validate a model to predict seizure freedom in children undergoing cerebral hemispheric surgery for the treatment of drug-resistant epilepsy.

METHODS

We analyzed 1267 hemispheric surgeries performed in pediatric participants across 32 centers and 12 countries to identify predictors of seizure freedom at 3 months after surgery. A multivariate logistic regression model was developed based on 70% of the dataset (training set) and validated on 30% of the dataset (validation set). Missing data were handled using multiple imputation techniques.

RESULTS

Overall, 817 of 1237 (66%) hemispheric surgeries led to seizure freedom (median follow-up = 24 months), and 1050 of 1237 (85%) were seizure-free at 12 months after surgery. A simple regression model containing age at seizure onset, presence of generalized seizure semiology, presence of contralateral 18-fluoro-2-deoxyglucose-positron emission tomography hypometabolism, etiologic substrate, and previous nonhemispheric resective surgery is predictive of seizure freedom (area under the curve = .72). A Hemispheric Surgery Outcome Prediction Scale (HOPS) score was devised that can be used to predict seizure freedom.

SIGNIFICANCE

Children most likely to benefit from hemispheric surgery can be selected and counseled through the implementation of a scale derived from a multiple regression model. Importantly, children who are unlikely to experience seizure control can be spared from the complications and deficits associated with this surgery. The HOPS score is likely to help physicians in clinical decision-making.

Incidence and Risk of Pneumococcal Pneumonia in Adults with Distinct Underlying Medical Conditions: A Population-Based Study

PURPOSE

This study investigated the incidence of pneumococcal pneumonia requiring hospitalisation among middle-aged and older adults with and without specific underlying medical conditions, evaluating the influence of these conditions in the risk of developing pneumonia.

METHODS

Population-based prospective cohort study included 2,025,730 individuals ≥ 50 years around Catalonia, Spain. The Catalonian information system for the development of research in primary care (SIDIAP) was used to establish baseline characteristics of the cohort (comorbidities and underlying medical conditions). Hospitalisations from pneumococcal pneumonia occurred among cohort members between 01/01/2015 and 31/12/2015 were collected from hospital discharge codes of 68 reference Catalonian hospitals. Cox regression was used to estimate the association between baseline conditions and the risk of developing pneumonia.

RESULTS

Global incidence rate (IR) of hospitalised pneumococcal pneumonia was 82.8 cases per 100,000 persons-year. Maximum IRs (per 100,000 persons-year) emerged among persons with haematological neoplasia (837.4), immunodeficiency (709.2), HIV infection (474.7), severe renal disease (407.5) and chronic pulmonary disease (305.7). In the multivariable analyses, apart from increasing age, HIV infection (hazard ratio [HR] 6.78), haematological neoplasia (HR 6.30), prior all-cause pneumonia (HR 5.27), immunodeficiency (HR 4.57) and chronic pulmonary disease (HR 2.89) were the conditions most strongly associated with an increasing risk. Pneumococcal vaccination did not emerge associated with a reduced risk in our study population (nor PPsV23 neither PCV13).

CONCLUSION

Old age, immunocompromising conditions and chronic pulmonary/respiratory disease are major risk factors for pneumococcal pneumonia in adults. Our data underline the need for better prevention strategies in these persons.

Ultrafast transient liquid assisted growth of high current density superconducting films

The achievement of high growth rates in YBa₂Cu₃O₇ epitaxial high-temperature superconducting films has become strategic to enable high-throughput manufacturing of long length coated conductors for energy and large magnet applications. We report on a transient liquid assisted growth process capable of achieving ultrafast growth rates (100 nm s⁻¹) and high critical current densities (5 MA cm⁻² at 77 K). This is based on the kinetic preference of Ba-Cu-O to form transient liquids prior to crystalline thermodynamic equilibrium phases, and as such is a non-equilibrium approach. The transient liquid-assisted growth process is combined with chemical solution deposition, proposing a scalable method for superconducting tapes manufacturing. Additionally, using colloidal solutions, the growth process is extended towards fabrication of nanocomposite films for enhanced superconducting properties at high magnetic fields. Fast acquisition in situ synchrotron X-ray diffraction and high resolution scanning transmission electron microscopy (STEM) become crucial measurements in disentangling key aspects of the growth process.

High throughput manufacturing of long length coated conductors requires fast epitaxial growth of high-temperature superconducting films. Here, Soler et al. report an ultrafast growth rates and high critical current densities of YBa₂Cu₃O₇ films using a transient liquid-assisted growth method.

[Opsoclonus myoclonus syndrome secondary to abdominal neuroblastoma. Presentation of a pediatric clinical case]

Opsoclonus-myoclonus syndrome is a rare disorder among pediatric patients. The diagnosis is clinical and is characterized by the presence of at least three of the following: opsoclonus, myoclonus, ataxia, irritability and sleep disorders. In over 50 % of cases it is associated with the presence of Neuroblastoma. It is a disorder of immune origin and its treatment is based on immunosuppressants, immunomodulators and tumor resection in cases secondary to Neuroblastoma. Up to 70 % to 80 % of cases may present neurological sequelae, depending on the cause, the initial severity of symptoms and the delay of proper treatment. We present the case of a 2-year-old male with diagnosis of opsoclonus-myoclonus syndrome secondary to a left adrenal Neuroblastoma. Tumor resection and treatment with corticosteroids, immunoglobulin and rituximab were performed.

Landau-Kleffner syndrome: a study of 29 patients

PURPOSE

The aim of the study was to retrospectively analyze the electroclinical features, etiology, treatment, and prognosis of 29 patients with Landau-Kleffner syndrome (LKS) with a long-term follow-up.

METHODS

Inclusion criteria were a diagnosis of LKS with: (1) acquired aphasia or verbal auditory aphasia; (2) with or without focal seizures, secondarily generalized tonic-clonic seizures, absences, or atonic seizures.

RESULTS

Mean follow-up was 12 years. All cases except six had seizures. Before the onset of aphasia, developmental language and behavioral disturbances were present in 19 and 14 patients, respectively. All patients had verbal auditory agnosia. Aphasia was severe in 24 patients and moderate in five. Nonlinguistic cognitive dysfunctions were moderate in 14 patients. Behavioral disturbances were found in 16 patients. During the continuous spike-and-wave discharges during slow sleep phase, the spike-wave index was >85% in 15, 50-85% in eight, and 30-50% in four. In two patients, the EEG recording showed occasional bilateral spikes, without continuous spike-and-wave discharges during slow sleep. In this phase, the awake EEG recording showed more frequent interictal abnormalities, predominantly in the temporal regions. Eight patients recovered language completely, but the remaining patients continue to have language deficits of different degrees.

CONCLUSION

Landau-Kleffner syndrome is an epileptic encephalopathy characterized by acquired verbal auditory aphasia and seizures in most of the patients associated with continuous or almost continuous spike-and-wave discharges during slow wave sleep. The most commonly used treatments were clobazam, ethosuximide, sulthiame. High-dose steroids were also administered. Adequate and early management may avoid language and cognitive deterioration.

Epilepsy with myoclonic atonic seizures: an electroclinical study of 69 patients

Epilepsy with myoclonic-atonic seizures is characterized by myoclonic-atonic, absence, tonic-clonic, and eventually tonic seizures, appearing in previously normal children at ages 18-60 months. We analyzed the electroclinical features, treatment, and outcome of 69 patients with myoclonic-atonic seizures; these patients were followed between 1990 and 2012 at the Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina. No structural or metabolic etiology was identified. Based on the electroclinical features and evolution, two groups could be distinguished. The first group of 39 patients with myoclonic and myoclonic-atonic seizures with or without generalized tonic-clonic seizures and absences associated with generalized spike- and polyspike-and-wave paroxysms had excellent prognoses. The second group of 30 patients had myoclonic jerks and myoclonic-atonic seizures associated with other seizure types including tonic seizures; some had myoclonic status epilepticus and cognitive deterioration. The interictal EEG showed frequent generalized spike- and polyspike-and-wave paroxysms. In 16 patients, the seizures remitted within 3.6 years. The two groups were distinguished in retrospect, when enough time had elapsed to evaluate cognitive deterioration and different seizure types. In conclusion, epilepsy with myoclonic atonic seizures is an epileptic syndrome with a broad clinical spectrum and variable prognosis.