Integrating Veterinary Diagnostic Laboratories for Emergency Use Testing during Pandemics1

The SARS-CoV-2 pandemic showed limitations in human outbreak testing. Veterinary diagnostic laboratories (VDLs) possess capabilities to bolster emergency test capacity. Surveys from 26 participating VDLs found human SARS-CoV-2 testing was mutually beneficial, including One Health benefits. VDLs indicated testing >3.8 million human samples during the pandemic, which included some challenges.

SARS-CoV-2 surveillance in a veterinary health system provides insight into transmission risks

OBJECTIVE

To investigate the prevalence and seropositivity of SARS-CoV-2 in companion and exotic animals in a veterinary healthcare system.

SAMPLE

A total of 341 animals were sampled by a combination of oral and nasal swabs. Serum from whole blood was collected from a subset of animals (86 canines, 25 felines, and 6 exotic animals).

METHODS

After informed owner consent, convenience samples from client-owned animals and the pets of students and staff members associated with Colorado State University's Veterinary Health System were collected between May 2021 and September 2022. Study samples were collected by trained veterinarians, Veterinary Health System staff, and veterinary students.

RESULTS

SARS-CoV-2 RNA was detected by reverse transcription PCR in 1.6% (95% CI, 0.5% to 4.6%) of domestic canines and 1.1% (95% CI, 0.2% to 6.1%) of domestic felines. No RNA was detected in any of the exotic animal species tested (n = 66). Plaque reduction neutralization tests indicated that 12.8% (95% CI, 7.3% to 21.5%) of canines and 12.0% (95% CI, 4.2% to 30.0%) of felines had neutralizing antibodies against SARS-CoV-2.

CLINICAL RELEVANCE

This study provides insight regarding SARS-CoV-2 spillover in domestic companion and exotic animals and contributes to our understanding of transmission risk in the veterinary setting.

Misidentification as Pseudomonas aeruginosa in hospital water supply samples

Drinking water in hospitals is often tested for Pseudomonas aeruginosa because of its virulence potential. This article describes a case where, based on EN ISO 16266, seven of 11 (64%) samples taken simultaneously from the drinking water system at a single hospital tested positive for P. aeruginosa. This resulted in extensive investigations and interventions, and a number of measures were implemented. However, supplementary analyses with more discriminatory power (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, 16S-rRNA sequencing) ruled out P. aeruginosa completely. The authors wish to raise awareness of this problem, and suggest that diagnostic uncertainty of results obtained by EN ISO 16266 should be indicated on laboratory reports. Wrongly assuming the presence of P. aeruginosa in hospital water supply systems can lead to unnecessary control measures, as analytical uncertainty massively influences the health risk assessment and the remediation measures initiated in medical environments.

The global prevalence of human fascioliasis: a systematic review and meta-analysis

Background

Fascioliasis is a parasitic zoonosis that can infect humans and be a source of significant morbidity. The World Health Organization lists human fascioliasis as a neglected tropical disease, but the worldwide prevalence of fascioliasis data is unknown.

Objective

We aimed to estimate the global prevalence of human fascioliasis.

Data sources and methods

We performed a systematic review and prevalence meta-analysis. We used the following inclusion criteria: articles published in the English, Portuguese, or Spanish languages from December 1985 to October 2022 and studies assessing the prevalence of Fasciola in the general population with an appropriate diagnostic methodology, including longitudinal studies, prospective and retrospective cohorts, case series, and randomized clinical trials (RCTs). We excluded animal studies. Two reviewers independently reviewed the selected studies for methodological quality, performing critical standard measures from JBI SUMARI. A random-effects model was conducted of the summary extracted data on the prevalence proportions. We reported the estimates according to the GATHER statement.

Results

In all, 5617 studies were screened for eligibility. Fifty-five studies from 15 countries were selected, including 154,697 patients and 3987 cases. The meta-analysis revealed a pooled prevalence of 4.5% [95% confidence interval (CI): 3.1-6.1; I² = 99.4%; T² = 0.07]. The prevalence in South America, Africa, and Asia was 9.0%, 4.8%, and 2.0%, respectively. The highest prevalence was found in Bolivia (21%), Peru (11%), and Egypt (6%). Subgroup analysis showed higher prevalence estimates in children, in studies from South America, and when Fas2-enzyme-linked immunosorbent assay (ELISA) was used as a diagnostic method. A larger study sample size (p = 0.027) and an increase in female percentage (p = 0.043) correlated with a decrease in prevalence. Multiple meta-regression showed a higher prevalence for hyperendemic than hypoendemic (p = 0.002) or mesoendemic (p = 0.013) regions.

Conclusion

The estimated prevalence and projected disease burden of human fascioliasis are high. Study findings support that fascioliasis continues to be a globally neglected tropical disease. Strengthening epidemiological surveillance and implementing measures to control and treat fascioliasis is imperative in the most affected areas.

First recorded outbreak of Veronaea botryosa in North American amphibians: Clinicopathologic features of a rare cause of phaeohyphomycosis in captive White's tree frogs (Litoria caerulea)

We describe fatal phaeohyphomycosis due to Veronaea botryosa in captive White’s tree frogs (Litoria caerulea), the first confirmed report in amphibians in North America. Over 15 months, six frogs developed ulcerative dermatitis on distal extremities/ventrum, which in one animal progressed to vasculitis and necrotizing osteomyelitis. All six frogs died. Clinicopathologic findings, diagnostic challenges, and control are discussed. Emerging fungi such as V. botryosa pose serious concerns for zoonosis and potential spread through the pet trade.

Real-world application of tumor mutational burden-high (TMB-high) and microsatellite instability (MSI) confirms their utility as immunotherapy biomarkers

Introduction

Microsatellite instability (MSI) testing and tumor mutational burden (TMB) are genomic biomarkers used to identify patients who are likely to benefit from immune checkpoint inhibitors. Pembrolizumab was recently approved by the Food and Drug Administration for use in TMB-high (TMB-H) tumors, regardless of histology, based on KEYNOTE-158. The primary objective of this retrospective study was real-world applicability and use of immunotherapy in TMB/MSI-high patients to lend credence to and refine this biomarker.

Methods

Charts of patients with advanced solid tumors who had MSI/TMB status determined by next generation sequencing (NGS) (FoundationOne CDx) were reviewed. Demographics, diagnosis, treatment history, and overall response rate (ORR) were abstracted. Progression-free survival (PFS) was determined from Kaplan–Meier curves. PFS1 (chemotherapy PFS) and PFS2 (immunotherapy PFS) were determined for patients who received immunotherapy after progressing on chemotherapy. The median PFS2/PFS1 ratio was recorded.

Results

MSI-high or TMB-H [≥20 mutations per megabase (mut/MB)] was detected in 157 adults with a total of 27 distinct tumor histologies. Median turnaround time for NGS was 73 days. ORR for most recent chemotherapy was 34.4%. ORR for immunotherapy was 55.9%. Median PFS for patients who received chemotherapy versus immunotherapy was 6.75 months (95% confidence interval, 3.9-10.9 months) and 24.2 months (95% confidence interval, 9.6 months to not reached), respectively (P = 0.042). Median PFS2/PFS1 ratio was 4.7 in favor of immunotherapy.

Conclusion

This real-world study reinforces the use of TMB as a predictive biomarker. Barriers exist to the timely implementation of NGS-based biomarkers and more data are needed to raise awareness about the clinical utility of TMB. Clinicians should consider treating TMB-H patients with immunotherapy regardless of their histology.

•

This retrospective study examined the real-world use of immune checkpoint inhibitors (ICIs) in TMB/MSI-high patients with a diverse set of cancer types.

•

TMB is an emerging tumor-agnostic biomarker for response to treatment with ICIs that may expand personalized cancer care.

•

ICIs remain underutilized as a first-line therapy for TMB/MSI-H patients without specific histologic approval for ICIs.

•

The PFS2 to PFS1 ratio was 4.7, favoring immunotherapy over chemotherapy even as a second-line therapy.

•

Our study reinforces the real-world evidence that TMB is a valid surrogate marker for MSI and can predict response to ICIs.

Pain relief and local tumour control following percutaneous image-guided cryoablation for spine metastasis: a 12-year single-centre experience

AIM

To assess pain relief and local tumour control retrospectively in spinal metastases undergoing cryoablation.

MATERIALS AND METHODS

Between May 2008 and September 2020, 46 metastases in 41 consecutive patients (mean age 59.7±4.4 [SD] years; range 27-84) were treated with cryoablation in 42 interventional sessions. Patient demographics, procedural data, complications, pain, and local tumour control were analysed retrospectively.

RESULTS

Thirty-one patients (36 spine metastases; 32 sessions) were treated for pain relief and 10 (10 metastases; 10 sessions) for local tumour control. Clinical success was reached in 30/32 (93.8%) interventional palliative sessions. Mean pre-procedural numerical pain rate scale was 6.2±1.7 (SD), and dropped significantly to 3.5±1.8 (SD), 1.9±1.7 (SD), and 1.9±1.8 (SD) at 24-h, 1-month and at the last available follow-up (median 16.5±23.2 [SD] months), respectively. For patients requiring local tumour control, primary clinical success was reached in 6/10 (60%) spinal metastases at median 25-months follow-up. The overall complication rate was 8%, with no secondary fractures or iatrogenic thermal-mediated nerve injuries reported.

CONCLUSION

Percutaneous image-guided cryoablation of spinal metastases is safe and effective in achieving pain relief and local tumour control.

ST18 affects cell-cell adhesion in pemphigus vulgaris in a tumour necrosis factor-α-dependent fashion

BACKGROUND

Pemphigus vulgaris (PV) is a life-threatening mucocutaneous autoimmune blistering disease. We previously showed that genetic variants within the ST18 gene promoter area confer a sixfold increase in the propensity to develop PV. ST18, a transcription factor, was found to be overexpressed in the epidermis of patients with PV. In addition, it was found to promote autoantibody-mediated abnormal epidermal cell-cell adhesion and secretion of proinflammatory mediators by keratinocytes.

OBJECTIVES

To delineate the mechanism through which ST18 contributes to destabilization of cell-cell adhesion.

METHODS

We used quantitative reverse-transcriptase polymerase chain reaction, immunofluorescence microscopy, a luciferase reporter system, site-directed mutagenesis, chromatin immunoprecipitation (ChIP) and the dispase dissociation assay.

RESULTS

The ChIP and luciferase reporter assays showed that ST18 directly binds and activates the TNF promoter. Accordingly, increased ST18 expression contributes to PV pathogenesis by destabilizing cell-cell adhesion in a tumour necrosis factor (TNF)-α-dependent fashion. In addition, dual immunofluorescence staining showed increased expression of both ST18 and TNF-α in the skin of patients with PV carrying an ST18-associated PV risk variant, which was found to be associated with a more extensive PV phenotype.

CONCLUSIONS

Our findings suggest a role for TNF-α in mediating the deleterious effect of increased ST18 expression in PV skin.

In situ XPS study of the surface chemistry of MAPI solar cells under operating conditions in vacuum

Organic–inorganic hybrid perovskite solar cells achieved a record efficiency of almost 23% in only a short time span of time.

Human presence impacts fungal diversity of inflated lunar/Mars analog habitat

BACKGROUND

An inflatable lunar/Mars analog habitat (ILMAH), simulated closed system isolated by HEPA filtration, mimics International Space Station (ISS) conditions and future human habitation on other planets except for the exchange of air between outdoor and indoor environments. The ILMAH was primarily commissioned to measure physiological, psychological, and immunological characteristics of human inhabiting in isolation, but it was also available for other studies such as examining its microbiological aspects. Characterizing and understanding possible changes and succession of fungal species is of high importance since fungi are not only hazardous to inhabitants but also deteriorate the habitats. Observing the mycobiome changes in the presence of human will enable developing appropriate countermeasures with reference to crew health in a future closed habitat.

RESULTS

Succession of fungi was characterized utilizing both traditional and state-of-the-art molecular techniques during the 30-day human occupation of the ILMAH. Surface samples were collected at various time points and locations to observe both the total and viable fungal populations of common environmental and opportunistic pathogenic species. To estimate the cultivable fungal population, potato dextrose agar plate counts method was utilized. The internal transcribed spacer region-based iTag Illumina sequencing was employed to measure the community structure and fluctuation of the mycobiome over time in various locations. Treatment of samples with propidium monoazide (PMA; a DNA intercalating dye for selective detection of viable microbial populations) had a significant effect on the microbial diversity compared to non-PMA-treated samples. Statistical analysis confirmed that viable fungal community structure changed (increase in diversity and decrease in fungal burden) over the occupation time. Samples collected at day 20 showed distinct fungal profiles from samples collected at any other time point (before or after). Viable fungal families like Davidiellaceae, Teratosphaeriaceae, Pleosporales, and Pleosporaceae were shown to increase during the occupation time.

CONCLUSIONS

The results of this study revealed that the overall fungal diversity in the closed habitat changed during human presence; therefore, it is crucial to properly maintain a closed habitat to preserve it from deteriorating and keep it safe for its inhabitants. Differences in community profiles were observed when statistically treated, especially of the mycobiome of samples collected at day 20. On a genus level Epiccocum, Alternaria, Pleosporales, Davidiella, and Cryptococcus showed increased abundance over the occupation time.

A Support Group for Caregivers of Patients with Frontotemporal Dementia

Several recent articles have pointed out that caregivers of patients with frontotemporal dementia (FTD) need counselling and support. To date, however, no support groups have been provided other than those available to caregivers of patients with Alzheimer's disease (AD). At our outpatient unit for cognitive disorders we initiated a specific support group for caregivers of patients with FTD. This pilot project had four objectives: 1) to provide information, advice and support to caregivers, 2) to learn more about the specific problems and needs of family carers of patients with FTD and to explore the differences to caregiver burden in AD, 3) to encourage mutual support and development of coping strategies, 4) to evaluate the intervention using a questionnaire completed by the caregiver. Eight spouse caregivers of patients diagnosed with frontotemporal dementia (FTD) participated in special support groups. Seven weekly sessions of 90 minutes' duration were held. To evaluate the program participants were asked to complete a questionnaire about their satisfaction with the support group immediately after the final session. Six months after the intervention they received a questionnaire by mail gathering information on coping efficacy. It became obvious that many problems faced by caregivers of patients with FTD are different from those encountered in AD. During group meetings participants were encouraged to express their own needs and to deal with painful emotions, including aggression, anger, mourning and guilt. Caregivers felt relieved by sharing their problems with others. They were able to learn from each other and to share coping strategies. The group also helped to establish new social relations contacts and even friendships. The participants rated the program as useful and said that benefits were sustained even six months after termination. We conclude from these initial observations that caregiver support groups are a useful component in the management of patients with FTD. Such groups should be tailored to the specific problems and needs of these caregivers. To maintain benefits, self-help groups are recommended even in the absence of professional input.

Investigation of sodium insertion into tetracyanoquinodimethane (TCNQ): results for a TCNQ thin film obtained by a surface science approach

In this contribution, we investigate the insertion of sodium into tetracyanoquinodimethane (TCNQ) and its effect on the electronic structure by means of a surface science experiment. We exposed a TCNQ thin film stepwise to sodium vapour and monitored the electronic structure by X-ray photoelectron spectroscopy (XPS) and ultra-violet photoelectron spectroscopy (UPS). During the insertion experiment three stages were observed, which can be related to three different phases, predominantly consisting of TCNQ(0), TCNQ(1-) and TCNQ(2-). With increasing sodium content the Fermi level shifts upwards and new electronic states appear in the band gap. For phases with high sodium content the sodium diffusion seems to be inhibited which we attribute to closed diffusion pathways in the molecular structure of TCNQ(1-).

Co-sputtered MoRe thin films for carbon nanotube growth-compatible superconducting coplanar resonators

Molybdenum rhenium alloy thin films can exhibit superconductivity up to critical temperatures of T(c)=15K. At the same time, the films are highly stable in the high-temperature methane/hydrogen atmosphere typically required to grow single wall carbon nanotubes. We characterize molybdenum rhenium alloy films deposited via simultaneous sputtering from two sources, with respect to their composition as function of sputter parameters and their electronic dc as well as GHz properties at low temperature. Specific emphasis is placed on the effect of the carbon nanotube growth conditions on the film. Superconducting coplanar waveguide resonators are defined lithographically; we demonstrate that the resonators remain functional when undergoing nanotube growth conditions, and characterize their properties as function of temperature. This paves the way for ultra-clean nanotube devices grown in situ onto superconducting coplanar waveguide circuit elements.

Density of states in graphene with vacancies: midgap power law and frozen multifractality

The density of states ϱ(E) of graphene is investigated numerically and within the self-consistent T-matrix approximation in the presence of vacancies within the tight binding model. The focus is on compensated disorder, where the concentration of vacancies n(A) and n(B) in both sublattices is the same. Formally, this model belongs to the chiral symmetry class BDI. The onlinear sigma model predicts for BDI a Gade-type singularity ϱ(E)∼|E|(-1)exp[-|log(E)|(-1/x)]. Our numerical data are comparable to this result in a preasymptotic regime that gives way, however, at even lower energies to ϱ(E)∼E(-1)|log(E)|(-x̃), 1≤x̃<2. We take this finding as evidence that, similar to the case of dirty d-wave superconductors, generic bipartite random hopping models may also exhibit unconventional (strong-coupling) fixed points for certain kinds of randomly placed scatterers if these are strong enough. Our research suggests that graphene with (effective) vacancy disorder is a physical representative of such systems.

[Bladder cancer screening with urine-based tumour markers - occupational medical experience]

OBJECTIVE

Bladder cancer responds favourably to treatment and has a good survival rate, provided it is diagnosed at an early stage. Established methods exist for the early detection, however, their specificity and positive predictive value are not yet satisfactory. Innovative markers have been proposed, but still require validation in prospective studies. We provide a literature-based short overview on the currently available and some proposed markers for the early detection of bladder cancer and evaluate the need for validation in further studies. We further provide some first results of such a recently finished study in an occupational setting.

MATERIAL AND METHODS

We conducted a prospective screening study over seven years in 1610 males with former occupational exposure to carcinogenic aromatic amines. Annual bladder cancer screening according to statutory requirements was offered. In addition to the regularly performed check for hematuria and urine cytology, the markers NMP22, UroVysion™ and survivin were performed in voided urine samples of the participants. Positive findings (not for survivin) were further followed through urethrocystoscopy.

RESULTS AND CONCLUSIONS

A total of 7219 urine samples were screened. During the study period 16 incidental and 4 recurrent bladder tumours, thereof three papillomas, occurred in a total of 19 participants. 14 out of twenty tumours were marker-positive, and all but two were early stage findings. Cell-based markers (cytology, UroVysion™) und molecular markers (NMP22, survivin) were largely complementary, thus acting as a "multi-marker panel". Eight of the tumours were identified by a positive cytology. Six tumours were not detected by any of the tumour markers. The results will be further evaluated through the inclusion of confounding factors, which have so far rarely been examined in other studies. This may lead to the development of tiered diagnostic strategies with the aim to reduce the number of invasive diagnostic procedures in the future.

[Burn trauma--Part 2. Anesthesiological, surgical and intensive care management]

After initial stabilization of burn victims at the scene and in the trauma room, a tight cooperation and communication between anesthesiologists, plastic surgeons and intensive care specialists is needed for further therapy. Interdisciplinary communication about preoperative planning, timing of necrectomy and intensive care therapy is vital regarding functional and aesthetic outcome and survival rate. During burn surgery attention has to be paid to excessive blood loss and the danger of hypothermia. The main problems of intensive care therapy involve the evaluation of volume status, high demands for analgesia and sedation, high incidence of septic multiorgan failure and therapy and prophylaxis of the effects of hypermetabolism.

Geochemistry and toxicity of sediment porewater in a salt-impacted urban stormwater detention pond

A comprehensive study was carried out to investigate the impacts of road salts on the benthic compartment of a small urban detention facility, Rouge River Pond. Although the pond is an engineered water body, it is representative of many small urban lakes, ponds and wetlands, which receive road runoff and are probable high impact areas. Specific objectives of the study were to document the porewater chemistry of an aquatic system affected by elevated salt concentrations and to carry out a toxicological assessment of sediment porewater to determine what factors may cause porewater toxicity. The results indicate that the sediment porewater may itself attain high salt concentrations. The computations show that increased chloride levels have important implications on the Cd complexation, augmenting its concentration in porewater. The toxicity tests suggest that the toxicity in porewater is caused by metals or other toxic chemicals, rather than high levels of chloride.

Outcome and predictors of interstitial radiosurgery in the treatment of gelastic epilepsy

BACKGROUND

Gelastic epilepsy due to hypothalamic hamartomas is usually a severe condition encompassing both epileptic seizures and an epileptic encephalopathy associated with behavioral and cognitive impairments. Here we report the effects of interstitial radiosurgery in the treatment of this generally pharmacoresistant epilepsy syndrome.

METHODS

Twenty-four consecutive patients (3-46 years of age, 7 women, mean age 21.9 years, mean duration of epilepsy 17.6 years) with gelastic epilepsy due to MR-ascertained hypothalamic hamartoma and a minimum follow-up period of 1 year were included in this evaluation. Treatment was performed by interstitial radiosurgery using stereotactically implanted (125)I seeds. Effects of treatment on seizure frequency and possible side effects were assessed prospectively. Factors influencing outcome and side effects were analyzed statistically.

RESULTS

After a mean 24-month follow-up period following the last radiosurgical treatment, 11/24 patients were seizure free or had seizure reduction of at least 90% (Engel class I and II), in some cases only after repeated treatment. The duration of epilepsy prior to radiosurgery negatively influenced outcome. Treatment was well tolerated in most patients. Headache, fatigue, and lethargy were transient side effects associated with the development of brain edema extending from the implantation site in five patients. Four patients had a weight gain of more than 5 kg which was severe in two patients. The majority of those patients whose cognitive functions initially deteriorated showed subsequent recovery of cognitive functions, but episodic memory in two patients showed persistent decline at 1 year follow-up. Longer disease duration increased the risk for cognitive side effects, and larger hamartoma size and eccentric seed positioning increased the risk for radiogenic brain edema. Neither perioperative mortality nor neurologic impairments, visual field defects, or endocrinologic disturbances were encountered following treatment.

CONCLUSION

Interstitial radiosurgery was efficacious in significantly improving gelastic epilepsy in about half of the patients treated in this series. Weight gain may occur as a side effect, whereas other severe side effects reported following microsurgical removal of the hamartoma were absent. The study results strongly suggest early causal treatment, as chances for seizure control are higher and the risk for cognitive side effects is lower in patients with shorter disease duration.

The Wada test in Austrian, Dutch, German, and Swiss epilepsy centers from 2000 to 2005: a review of 1421 procedures

Twenty-six Austrian, Dutch, German, and Swiss epilepsy centers were asked to report on use of the Wada test (intracarotid amobarbital procedure, IAP) from 2000 to 2005 and to give their opinion regarding its role in the presurgical diagnosis of epilepsy. Sixteen of the 23 centers providing information had performed 1421 Wada tests, predominantly the classic bilateral procedure (73%). A slight nonsignificant decrease over time in Wada test frequency, despite slightly increasing numbers of resective procedures, could be observed. Complication rates were relatively low (1.09%; 0.36% with permanent deficit). Test protocols were similar even though no universal standard protocol exists. Clinicians rated the Wada test as having good reliability and validity for language determination, whereas they questioned its reliability and validity for memory lateralization. Several noninvasive functional imaging techniques are already in use. However, clinicians currently do not want to rely solely on noninvasive functional imaging in all patients.

Occurrence of alkylphenolic substances in a Great Lakes coastal marsh, Cootes Paradise, ON, Canada

Occurrence and fate of alkylphenols (APs), known endocrine disruptors, were investigated in a Great Lakes coastal wetland, Cootes Paradise, ON. The wetland, which receives discharges from a Wastewater Treatment Plant (WTP) and several Combined Sewer Overflows (CSOs), is an important spawning ground for fish and crucial habitat for other fauna. Elevated concentrations of nonylphenol ethoxylates (NPEs) and their degradation product nonylphenol (NP) were found in water and sediment samples near the sources. Since transfer of APs through the food chain is of concern, we compared their concentrations in invertebrates from clean and contaminated sites. The results reveal transfer of alkylphenolics from sediments to biota and their accumulation in the invertebrate tissue, particularly the highly hydrophobic 4-NP, whose concentrations ranged from 1.9 to 6.3 microg g(-1). To our knowledge, this is the first study to evaluate AP concentrations in tissue of benthic invertebrates under real environmental conditions.

Assessment of cognitive functions before and after stereotactic interstitial radiosurgery of hypothalamic hamartomas in patients with gelastic seizures

We assessed cognitive functions before and 3 months after interstitial radiotherapy in 14 patients with gelastic seizures caused by hypothalamic hamartoma. Cognitive functioning was assessed before temporary implantation of (125)I-seed and 3 months after seed explantation. Performance was compared with that of a selected control group of conservatively treated patients with symptomatic focal epilepsy tested before add-on treatment with a new antiepileptic drug and after reaching steady state. No short-term negative side effects of the interstitial radiosurgery could be observed for the domains of attention and executive functions and verbal and figural memory performance. Cognitive development of the patients treated with seeds was comparable to that of the control group at both assessments. Thus, the stereotactic implantation of (125)I-seeds in this patient group with gelastic seizures caused by hypothalamic hamartoma provides a well-tolerated minimally invasive method in the treatment of this severe epileptic syndrome without negative cognitive side effects.