Cognitive and behavioral problems in children with neurofibromatosis type 1: challenges and future directions

The role of unidentified bright objects in the neurocognitive profile of neurofibromatosis type 1 children: a volumetric MRI analysis

PURPOSE

Cognitive impairment is described in 80% of Neurofibromatosis type 1 (NF1) patients. Brain focal areas of T2w increased signal intensity on MRI, the so-called Unidentified Bright Objects (UBOs) have been hypothesized to be related to cognitive dysfunction, although conflicting results are available in literature. Here, we investigated the possible relation between UBOs' volume, cognitive impairment, and language disability in NF1 patients.

MATERIAL AND METHODS

In this retrospective study, clinical and MRI data of 21 NF1 patients (M/F = 12/9; mean age 10.1 ± 4.5) were evaluated. Brain intellectual functioning and language abilities were assessed with specific scales, while the analyzed MRI sequences included axial 2D-T2-weighted and FLAIR sequences. These images were used independently for UBOs segmentation with a semiautomatic approach and obtained volumes were normalized for biparietal diameters to take into account for brain volume. Possible differences in terms of normalized UBOs volumes were probed between cognitively affected and preserved patients, as well as between subjects with or without language impairment.

RESULTS

Patients cognitively affected were not different in terms of UBOs volume compared to those preserved (p = 0.35 and p = 0.30, for T2-weighted and FLAIR images, respectively). Similarly, no differences were found between patients with and without language impairment (p = 0.47 and p = 0.40, for the two sequences).

CONCLUSIONS

The relation between UBOs and cognition in children with NF1 has been already investigated in literature, although leading to conflicting results. Our study expands the current knowledge, showing a lack of correlation between UBOs volume and both cognitive impairment and language disability in NF1 patients.

The efficacy of statins for improving cognitive impairments in pediatric patients with neurofibromatosis type 1 (NF-1): a meta-analysis

Background

Given the considerable discrepancies in the evidence concerning the efficacy of statins in ameliorating cognitive impairments in pediatric patients with Neurofibromatosis Type 1 (NF-1), this study conducts a systematic review and meta-analysis to consolidate existing evidence to evaluate the efficacy of statins on cognitive impairments in children with NF-1.

Methods

This study adhered to the PRISMA statement, and the research protocol was pre-registered on PROSPERO (#CRD: 42022369072). Comprehensive searches of databases including PubMed, Embase, and the Cochrane Library were performed up to March 31, 2023 to identify randomized controlled trials (RCTs) investigating the effects of statins on cognitive impairments in children with NF-1. Statistical analyses were conducted using Review Manager 5.4.1. A fixed- or random-effects model was employed according to the I2 statistic. As all data were continuous, MD [95% CI] was used as the pooled estimate.

Results

The final analysis included five RCTs with a total of 364 patients. The meta-analysis indicated that aside from a statistically significant improvement in internalizing problems (MD [95%CI] = 3.61[0.11, 7.10], p = 0.04), Object assembly Test (MD [95%CI] = 0.53[0.12, 0.93], p = 0.01), Cancellation Test (MD [95%CI] = 3.61[0.11, 7.10], p < 0.0001), statins did not exhibit significant efficacy in improving other cognitive aspects in children with NF-1 (p > 0.05). An additional descriptive analysis on indices that cannot be meta-analyzed revealed considerable inconsistency in the therapeutic effect of statins across different studies.

Conclusion

Current evidence suggests that statins may not be effective for cognitive performance in children with NF-1.

Shedding New Light: Novel Therapies for Common Disorders in Children with Neurofibromatosis Type I

Neurofibromatosis type I (NF1) is a common dominantly inherited disorder, and one of the most common of the RASopathies. Most individuals with NF1 develop plexiform neurofibromas and cutaneous neurofibromas, nerve tumors caused by NF1 loss of function in Schwann cells. Cell culture models and mouse models of NF1 are being used to test drug efficacy in preclinical trials, which led to Food and Drug Administration approval for use of MEK inhibitors to shrink most inoperable plexiform neurofibromas. This article details methods used for testing in preclinical models, and outlines newer models that may identify additional, curative, strategies.

Benefits of intervention in the Central Auditory Nervous System in individuals with Neurofibromatosis Type 1

OBJECTIVE

To verify the effectiveness of acoustically controlled auditory training in individuals with Neurofibromatosis Type 1.

METHODS

The sample consisted of individuals with Neurofibromatosis Type 1, randomly distributed into two groups, making up the intervention group: individuals undergoing formal auditory training; and the comparison group: individuals who were not submitted to the intervention. Behavioral assessment of central auditory processing and electrophysiological evaluation, composed by Brainstem Auditory Evoked Potential and Long Latency-P300 Auditory Evoked Potential, were evaluated in three moments of evaluations: initial evaluation, reevaluation and after four months of reevaluation and comparing the performance between the groups.

RESULTS

Better performances in central auditory processing were observed after the formal auditory training in the intervention group with significant differences between the evaluations and performance maintenance four months after the end of the training. Significant differences were observed between the groups in the evaluations after the intervention. The electrophysiological evaluation shows unsystematic variation in the short latency potentials and changes in the long latency potentials with the appearance of the P3 wave after the intervention. The behavioral and electrophysiological evaluation in group that was not submitted to the intervention demonstrated that there is no improvement without the intervention, with deterioration of performance. Significant differences were observed in the behavioral and electrophysiological evaluations, in favor of the group submitted to formal auditory training.

CONCLUSIONS

Formal auditory training is effective in rehabilitation in individuals with Neurofibromatosis Type 1.

DESCRIPTORS/KEYWORDS

Neurofibromatosis 1; Hearing Disorders; Auditory Perceptual Disorders; Acoustic Stimulation; Evoked Potentials, Auditory.

Evaluating Focal Areas of Signal Intensity (FASI) in Children with Neurofibromatosis Type-1 (NF1) Treated with Selumetinib on Pediatric Brain Tumor Consortium (PBTC)-029B

Background: Understanding the effect of selumetinib on FASI may help elucidate the biology, proliferative potential, and role in neurocognitive changes for these NF1-associated lesions. Methods: Patients with NF1-associated LGG and FASI treated with selumetinib on PBTC-029B were age-matched to untreated patients with NF1-associated FASI at Cincinnati Children’s Hospital Medical Center. Paired bidirectional measurements were compared over time using nonparametric tests. Results: Sixteen age-matched pairs were assessed (age range: 2.8–16.9 years, 60% male). Initial FASI burden was not different between groups (median range 138.7 cm2 [88.4–182.0] for the treated subjects vs. 121.6 cm2 [79.6—181.9] for the untreated subjects; p = 0.98). Over a mean follow-up of 18.9 (±5.9) months, the LGG size consistently decreased with treatment while no consistent change among the treated or untreated FASI size was seen. At the paired time points, the median treated LGG decreased significantly more than the treated FASI (−41.3% (LGG) versus −10.7% (FASI), p = 0.006). However, there was no difference in the median size change in the treated versus untreated FASI (−10.7% (treated FASI) versus −17.9% (untreated FASI), p = 0.08). Among the treated subjects, there was no correlation between the change in LGG and FASI (r = −0.04, p = 0.88). Conclusions: Treatment with selumetinib did not affect the overall FASI size in children with NF1 treated for progressive low-grade glioma.

Comprehensive neurological evaluation of a cohort of patients with neurofibromatosis type 1 from a single institution

Neurofibromatosis type 1 (NF1) is a phenotypically heterogenous multisystem cancer predisposition syndrome manifesting in childhood and adolescents. Central nervous system (CNS) manifestations include structural, neurodevelopmental, and neoplastic disease. We aimed to (1) characterize the spectrum of CNS manifestations of NF1 in a paediatric population, (2) explore radiological features in the CNS by image analyses, and (3) correlate genotype with phenotypic expression for those with a genetic diagnosis. We performed a database search in the hospital information system covering the period between January 2017 and December 2020. We evaluated the phenotype by retrospective chart review and imaging analysis. 59 patients were diagnosed with NF1 [median age 10.6 years (range, 1.1-22.6); 31 female] at last follow-up, pathogenic NF1 variants were identified in 26/29. 49/59 patients presented with neurological manifestations including 28 with structural and neurodevelopmental findings, 16 with neurodevelopmental, and 5 with structural findings only. Focal areas of signal intensity (FASI) were identified in 29/39, cerebrovascular anomalies in 4/39. Neurodevelopmental delay was reported in 27/59 patients, learning difficulties in 19/59. Optic pathway gliomas (OPG) were diagnosed in 18/59 patients, 13/59 had low-grade gliomas outside the visual pathways. 12 patients received chemotherapy. Beside the established NF1 microdeletion, neither genotype nor FASI were associated with the neurological phenotype. NF1 was associated with a spectrum of CNS manifestations in at least 83.0% of patients. Regular neuropsychological assessment complementing frequent clinical and ophthalmologic testing for OPG is necessary in the care of each child with NF1.

Mapping the Landscape of Neurofibromatosis: A Bibliometric Evaluation Highlighting Our Current Understanding, Emerging Therapies, and Global Research Trends

BACKGROUND

The literature on neurofibromatosis (NF) has never been systematically assessed using bibliometric analytic methodologies. We quantitatively analyzed the major trends and scientific output regarding NF, highlighting potential avenues for research.

METHODS

An Elsevier's Scopus database search was performed for all indexed studies related to NF from 1898 to 2021. Validated bibliometric parameters were analyzed using productivity, citation, and keyword analysis, including text mining, content analysis, and collaboration network mapping from inception to date on R 4.1.2.

RESULTS

Our search yielded 15,024 documents. Annual scientific production has grown at a compounded rate of 5.86%, with the largest occurring in 2021 (n = 626). Journals with the most publications on NF include the Journal of Medical Genetics (n = 117) and Neurology (n = 113). The topmost cited author was Gutmann DH (n = 295). The United States had the most international collaboration (n = 435; multiple country publications). Identification of citation classics revealed a shift in recent decades towards understanding genetic and molecular pathways of NF tumorigenesis. Macro-level and micro-level text mining revealed the top 20 genetic and molecular pathways, and syndromes, associated with NF.

CONCLUSIONS

Our study exemplifies a quantitative method for understanding the historical and current state of academic efforts regarding NF. There has been a shift of treatment strategies towards targeting specific pathways involved in tumorigenesis. We highlight the top 20 genetic and molecular pathways in the literature as well as the top 20 associated syndromes. This data is encouraging as increased research in molecular targeted therapies aimed at NF pathogenesis may allow advances in disease control.

Cognitive and behavioral functioning in two neurogenetic disorders; how different are these aspects in Duchenne muscular dystrophy and Neurofibromatosis type 1?

The presence of neurocognitive and behavioral problems are common features in various neurogenetic disorders. In Duchenne muscular dystrophy (DMD), these problems have been linked to mutations along the dystrophin gene affecting different brain dystrophin isoforms. However, comparable cognitive and behavioral problems have been found in Neurofibromatosis type 1 (NF1). This study aims to assess disorder specific differences in cognition and behavior between DMD and NF1. Retrospective data of 38 male patients with DMD were aged-matched with data of 38 male patients with NF1. Patients of both groups underwent neurocognitive assessment for regular clinical care. Intellectual abilities, sequential and simultaneous processing, verbal memory and sustained attention were evaluated. In addition, parents and teachers completed behavioral questionnaires. Males with DMD exhibited low intellectual abilities and sequential processing problems, but these outcomes not significantly differed from males with NF1. Simultaneous processing, verbal memory and sustained attention outcomes were equal for both groups. Outcomes of questionnaires displayed higher rates of aggressive behavior (13.2%) in DMD, whereas in NF1 higher rates of problems with thinking (15.8%), withdrawn (10.5%) and social behavior (10.5%) were noticed. In the neurogenetic disorders DMD and NF1, on average overlapping cognitive and behavioral problems are noticed, suggesting that these are not only caused by gene mutations resulting in a lack of one specific protein.

The RASopathies: Biology, genetics and therapeutic options

The RASopathies are a group of genetic diseases in which the Ras/MAPK signaling pathway is inappropriately activated as a result of mutations in genes encoding proteins within this pathway. As their causative mutations have been identified, this group of diseases has expanded to include neurofibromatosis type 1 (NF1), Legius syndrome, Noonan syndrome, CBL syndrome, Noonan syndrome-like disorder with loose anagen hair, Noonan syndrome with multiple lentigines, Costello syndrome, cardiofaciocutaneous syndrome, gingival fibromatosis and capillary malformation-arteriovenous malformation syndrome. Many of these genetic disorders share clinical features in common such as abnormal facies, short stature, varying degrees of cognitive impairment, cardiovascular abnormalities, skeletal abnormalities and a predisposition to develop benign and malignant neoplasms. Others are more dissimilar, even though their mutations are in the same gene that is mutated in a different RASopathy. Here, we describe the clinical features of each RASopathy and contrast them with the other RASopathies. We discuss the genetics of these disorders, including the causative mutations for each RASopathy, the impact that these mutations have on the function of an individual protein and how this dysregulates the Ras/MAPK signaling pathway. As several of these individual disorders are genetically heterogeneous, we also consider the different genes that can be mutated to produce disease with the same phenotype. We also discuss how our growing understanding of dysregulated Ras/MAPK signaling had led to the development of new therapeutic agents and what work will be critically important in the future to improve the lives of patients with RASopathies.

Assessing Psychiatric Comorbidity and Pharmacologic Treatment Patterns Among Patients With Neurofibromatosis Type 1

Background and objective

Neurofibromatosis 1 (NF1) is a genetic disorder that is accompanied by psychiatric comorbidities such as depression, anxiety, and attention-deficit hyperactivity disorder (ADHD) in more than half of the patients. However, there are limited data describing optimal treatment strategies for these conditions. This study aimed to address that gap in understanding and explore the neurobiological basis of psychiatric comorbidities in NF1.

Materials and methods

A retrospective cohort study was conducted among NF1 patients with a comorbid diagnosis of depression, anxiety, and/or ADHD. These disease states were chosen based on their relatively high reported prevalence in NF1 and shared pathophysiological mechanisms via monoaminergic dysfunction. Information regarding demographics, psychotherapeutic medication use, and clinical outcomes was gathered from electronic medical records. Relationships between patient- and medication-related factors and outcome measures were assessed using statistical analysis.

Results

The study population (n = 82) consisted of NF1 patients with a comorbid diagnosis of depression (76.8%), anxiety (53.7%), and/or ADHD (23.2%). The use of second-generation antipsychotic agent augmentation therapy or hydroxyzine monotherapy was associated with significantly more behavioral health (BH)-related emergency department (ED) visits, admissions, and inpatient days in the study population. Conversely, the use of bupropion augmentation therapy, buspirone augmentation therapy, and stimulants was associated with improved clinical outcomes, though these results were not statistically significant.

Conclusions

Based on our findings in this real-world study setting, patients with NF1 and psychiatric comorbidities appear to experience significant benefits from medications that enhance dopaminergic neurotransmission (e.g., bupropion, stimulants) when compared to drugs that oppose it (e.g., second-generation antipsychotics).

Genodermatoses with behavioural sequelae

Children with genodermatoses are at an increased risk of developing behavioural disorders which may impart lasting damage on the individual and their family members. As such, early recognition of childhood mental health disorders via meticulous history taking, thorough physical examination, and disorder-specific testing is of paramount importance for timely and effective intervention. If carried out properly, prompt psychiatric screening and intervention can effectively mitigate, prevent or even reverse, the psychiatric sequela in question. To that end, this review aims to inform the concerned physician of the manifestations and treatment strategies relevant to the psychological sequelae of genodermatoses.

Importance of Thalamostriatal Pathway Associated With Neurocognitive Dysfunctions in Children With Neurofibromatosis Type 1: Diffusion Tensor Imaging Findings

OBJECTIVE

To determine whether there is a difference between healthy control group and children with neurofibromatosis type 1 (NF1) in terms of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values in different regions of the brain associated with neurocognitive functions and to investigate the correlation between diffusion tensor imaging parameters and neurocognitive dysfunctions.

METHODS

The study included 28 children with NF1 and 21 controls. Nine distinct areas related to cognitive functions were selected for the analysis. The ADC and FA values were compared.

RESULTS

There was a significant difference between NF1 and healthy control in terms of ADC values obtained from all areas. The ADC values at obtained from thalamus and striatum were positively correlated with the full-scale intelligence quotient (IQ), verbal IQ, and performance IQ.

CONCLUSIONS

We are speculated that the development of microstructural damage in the thalamostriatal pathway may lead to neurocognitive dysfunction.

Long-term cognitive deficits in pediatric low-grade glioma (LGG) survivors reflect pretreatment conditions-report from the German LGG studies

Background

Disease and treatment contribute to cognitive late effects following pediatric low-grade glioma (LGG). We analyzed prospectively collected neuropsychological data of German pediatric LGG survivors and focused on the impact of hydrocephalus at diagnosis, neurofibromatosis type 1 (NF1) status, and extent of surgery.

Methods

We used the Neuropsychological Basic Diagnostic screening tool based on the Cattell-Horn-Carroll model for intelligence and the concept of cross-battery assessment at 2 and 5 years from diagnosis for 316 patients from the German pediatric LGG study and LGG registry (7.1 years median age; 45 NF1; cerebral hemispheres 16%, supratentorial midline 39%, infratentorial 45%). Hydrocephalus was classified radiologically in 137 non-NF1 patients with infratentorial tumors (95/137 complete/subtotal resection).

Results

Patients with NF1 versus non-NF1 exhibited inferior verbal short-term memory and visual processing (P < .001-.021). In non-NF1 patients, infratentorial tumor site and complete/subtotal resection were associated with sequelae in visual processing, psychomotor speed, and processing speed (P < .001-.008). Non-NF1 patients without surgical tumor reduction and/or nonsurgical treatment experienced similar deficits. Degree of hydrocephalus at diagnosis had no further impact. Psychomotor and processing speed were impaired comparably following chemo-/radiotherapy (P < .001-.021). Pretreatment factors such as NF1 or tumor site were relevant at multivariate analysis.

Conclusions

All pediatric LGG survivors are at risk to experience long-term cognitive impairments in various domains. Even surgical only management of cerebellar LGG or no treatment at all, that is, biopsy only/radiological diagnosis did not protect cognitive function. Since pattern and extent of deficits are crucial to tailor rehabilitation, neuropsychological and quality of survival assessments should be mandatory in future LGG trials.

Cognitive functioning and pain interference mediate pain predictive effects on health-related quality of life in pediatric patients with Neurofibromatosis Type 1

OBJECTIVES

The objective was to investigate the serial mediating effects of perceived cognitive functioning and pain interference in daily living in the relationship between perceived pain and overall generic health-related quality of life (HRQOL) in children, adolescents, and young adults with Neurofibromatosis Type 1 (NF1).

METHODS

The Pain, Cognitive Functioning, and Pain Impact Scales from the PedsQL Neurofibromatosis Type 1 Module and the PedsQL 4.0 Generic Core Scales were completed in a multi-site national study by 323 patients ages 5-25 and 335 parents. A serial multiple mediator model analysis was conducted to test the hypothesized sequential mediating effects of cognitive functioning and pain interference as intervening variables in the association between pain as a predictor variable and overall generic HRQOL.

RESULTS

Pain predictive effects on overall generic HRQOL were serially mediated by cognitive functioning and pain interference. In predictive analytics models utilizing hierarchical multiple regression analyses with age and gender demographic covariates, pain, cognitive functioning and pain interference accounted for 66% of the variance in patient-reported generic HRQOL and 57% of the variance in parent proxy-reported generic HRQOL (P < 0.001), reflecting large effect sizes.

CONCLUSIONS

Cognitive functioning and pain interference explain in part the mechanism of pain predictive effects on overall generic HRQOL in pediatric patients with NF1. Identifying NF1-specific pain, cognitive functioning, and pain interference as salient predictors of overall generic HRQOL from the patient and parent perspective facilitates a family-centered orientation to the comprehensive care of children, adolescents, and young adults with NF1.

Phenotype categorization of neurofibromatosis type I and correlation to NF1 mutation types

Neurofibromatosis type 1 (NF1) is caused by heterozygous mutation in the NF1 gene. NF1 is one of the most common human genetic diseases. However, the overall genotype-phenotype correlation has not been known, due to a wide spectrum of genotypic and phenotypic heterogeneity. Here we describe the detailed clinical and genetic features of 427 Korean NF1 patients from 389 unrelated families. Long range PCR and sequencing of genomic DNA with multiplex ligation-dependent probe amplification analysis identified 250 different NF1 mutations in 363 families (93%), including 94 novel mutations. With an emphasis on phenotypes requiring medical attention (classified and termed: NF1⁺), we investigated the correlation of NF1⁺ and mutation types. NF1⁺ was more prevalent in patients with truncating/splicing mutations and large deletions than in those with missense mutations (59.6%, 64.3% vs. 36.6%, p = 0.001). This difference was especially significant in the patients younger than age 19 years. The number of items in NF1⁺ was a higher in the former groups (0.95 ± 0.06, 1.18 ± 0.20 vs. 0.56 ± 0.10, p = 0.002). These results suggest that mutation types are associated not only with higher prevalence of severe phenotypes in NF1 but also with their earlier onset.

Discriminating between neurofibromatosis-1 and typically developing children by means of multimodal MRI and multivariate analyses

Neurofibromatosis Type 1 leads to brain anomalies involving both gray and white matter. The extent and granularity of these anomalies, together with their possible impact on brain activity, is still unknown. In this multicentric cross-sectional study we submitted a sample of 42 typically developing and 38 neurofibromatosis-1 children to a multimodal MRI assessment including T1, diffusion weighted and resting state functional sequences. We used a pipeline involving several features selection steps coupled with multivariate statistical analysis (supporting vector machine) to discriminate between the two groups while having interpretable models. We used MRI indexes measuring macro (gray matter volume) and microstructural (fractional anisotropy, mean diffusivity) characteristics of the brain, as well as indexes of brain activity (fractional amplitude of low frequency fluctuations) and connectivity (local and global correlation) at rest. We found that structural indexes could discriminate between the two groups, with the mean diffusivity leading to performance as high as the combination of all structural indexes combined (accuracy = 0.86), while functional indexes had worse performances. The MRI signature of NF1 brain pathology is a combination of gray and white matter abnormalities, as measured with gray matter volume, fractional anisotropy, and mean diffusivity.

Recent Advances in the Diagnosis and Pathogenesis of Neurofibromatosis Type 1 (NF1)-associated Peripheral Nervous System Neoplasms

The diagnosis of a neurofibroma or a malignant peripheral nerve sheath tumor (MPNST) often raises the question of whether the patient has the genetic disorder neurofibromatosis type 1 (NF1) as well as how this will impact the patient's outcome, what their risk is for developing additional neoplasms and whether treatment options differ for NF1-associated and sporadic peripheral nerve sheath tumors. Establishing a diagnosis of NF1 is challenging as this disorder has numerous neoplastic and non-neoplastic manifestations which are variably present in individual patients. Further, other genetic diseases affecting the Ras signaling cascade (RASopathies) mimic many of the clinical features of NF1. Here, we review the clinical manifestations of NF1 and compare and contrast them with those of the RASopathies. We also consider current approaches to genetic testing for germline NF1 mutations. We then focus on NF1-associated neurofibromas, considering first the complicated clinical behavior and pathology of these neoplasms and then discussing our current understanding of the genomic abnormalities that drive their pathogenesis, including the mutations encountered in atypical neurofibromas. As several neurofibroma subtypes are capable of undergoing malignant transformation to become MPNSTs, we compare and contrast patient outcomes in sporadic, NF1-associated and radiation-induced MPNSTs, and review the challenging pathology of these lesions. The mutations involved in neurofibroma-MPNST progression, including the recent identification of mutations affecting epigenetic regulators, are then considered. Finally, we explore how our current understanding of neurofibroma and MPNST pathogenesis is informing the design of new therapies for these neoplasms.

Neuropsychological profile in Italian children with neurofibromatosis type 1 (NF1) and their relationships with neuroradiological data: Preliminary results

BACKGROUND

Neurofibromatosis type 1 is a genetic disorder associated with cognitive deficits, learning disabilities and behavioral problems. These domains appear to have a still controversial debated association with local areas of T2-hyperintensities on MRI images, called unidentified bright objects (UBOs).

METHODS

A cohort of 36 children (aged 7-11 years) included consecutively, underwent neuropsychological and behavioral assessment to determine their cognitive and neuropsychological profile, and the frequency of specific learning disabilities. MRI examination was used to determine the impact of UBOs' presence, number, and location on the cognitive, neuropsychological and behavioral profile, and also the presence of optic glioma.

RESULTS

The mean full intelligence quotient was 104.6; only one child had mild intellectual disability. Forty one percent of children had a diagnosis of specific learning disabilities and reading was mainly involved. Twenty per cent had attention problems. All children had normal scores in visuo-motor and visuo-perceptual tests. UBOs were present in 94.0% of the MRI examinations. Two children had optic glioma. Children with UBOs in a specific location and children with UBOs elsewhere were statistically compared, no one of the location seemed to have an impact on general cognition measured with full intelligence quotient. The thalamus was associated with problems in calculation and striatum with behavioral problems. An inverse relationship between the number of UBOs and the full intelligence quotient was present, but without a statistical significance.

CONCLUSIONS

In this study, the specific location of UBOs did not seem to influence the general cognitive profile and also the relationship between their number and the full intelligence quotient was not significant; these results are still controversial in literature. Finally, the presence of UBOs in the thalamus and striatum may represent a neuroradiological pattern that influences performances in calculation and behavior respectively in children with Neurofibromatosis type 1.

Computerized cognitive training for children with neurofibromatosis type 1: A pilot resting-state fMRI study

In this pilot study, we examined training effects of a computerized working memory program on resting state functional magnetic resonance imaging (fMRI) measures in children with neurofibromatosis type 1 (NF1). We contrasted pre- with post-training resting state fMRI and cognitive measures from 16 participants (nine males; 11.1 ± 2.3 years) with NF1 and documented working memory difficulties. Using non-parametric permutation test inference, we found significant regionally specific differences (family-wise error corrected) in two of four voxel-wise resting state measures: fractional amplitude of low frequency fluctuations (indexing peak-to-trough intensity of spontaneous oscillations) and regional homogeneity (indexing local intrinsic synchrony). Some cognitive task improvement was observed as well. These preliminary findings suggest that regionally specific changes in resting state fMRI indices may be associated with treatment-related cognitive amelioration in NF1. Nevertheless, current results must be interpreted with caution pending independent controlled replication.

Cognitive profile and disorders affecting higher brain functions in paediatric patients with neurofibromatosis type 1

INTRODUCTION

Neurofibromatosis type 1 (NF1) is a common neurocutaneous syndrome often associated with specific cognitive deficits that are rarely monitored during follow-up of these patients.

OBJECTIVE

The purpose of our study is two-fold. First, we aimed to describe the cognitive profile of patients with NF1 and detect disorders in higher brain functions associated with the disease. Second, we identified the reasons for consultation associated with school performance in these patients.

METHODS

We conducted a descriptive cross-sectional study of 24 paediatric patients (ages 5 to 16) with NF1 who underwent neuropsychological assessment.

RESULTS

The most frequent reasons for consultation were attention deficits (58.33%), learning disorders (25%), poor motor coordination (25%), and language impairment (0.8%). Although 96% of the patients displayed impairments in at least one of the assessed areas, only 83.34% of the parents had reported such impairments. Attention-deficit/hyperactivity disorder was present in 58.33% of the patients, whereas 33.33% had nonverbal learning disabilities, 20.83% had expressive language disorder, 8.33% had borderline intellectual functioning, 4.16% had mental retardation, and only 4.16% showed no cognitive impairment.

CONCLUSION

Higher brain functions are frequently impaired in paediatric patients with NF1. Although many parents report such disorders, they can go undetected in some cases. Neuropsychological assessment is recommended for all paediatric patients with NF1 to detect cognitive impairment and provide early, effective rehabilitation treatment.

Cognitive and Behavioral Disorders in Children with Neurofibromatosis Type 1

AIM

The last systematic review of research on the behavior of children with neurofibromatosis type 1 (NF1) was in 2012. Since then, several important findings have been published. Therefore, the study aim was to synthesize recent relevant work related to this issue.

METHOD

We conducted a systematic review of the literature. Relevant articles were identified using the electronic databases PubMed, PsycINFO, and Scopus and a manual search of references lists. Thirty of 156 articles identified met the inclusion criteria. A quality evaluation of the articles was performed and the information was synthesized using a narrative approach.

RESULTS

Compared with controls, children and adolescents with NF1 present significant alterations in language, reading, visuospatial skills, motor function, executive function, attention, behavior, emotion, and social skills. The prevalence of attention-deficit/hyperactivity disorder (ADHD) is important and can affect cognition and executive function variables. A high prevalence of autistic traits and autistic spectrum disorder were reported. The benefits of using statins to treat cognitive deficits are unclear. However, children with NF1 and ADHD seem to benefit from methylphenidate treatment. The presence of hyperintensities in brain magnetic resonance imaging data seem to be related to poor cognitive performance. Analysis of these lesions could help to predict cognitive alterations in children with NF1.

INTERPRETATION

There has been important progress to evaluate cognitive characteristics of children with NF1 and to determine the physiological mechanisms of the concomitant disorders. However, discrepancies in relation to intelligence, learning disabilities, attention deficits, and treatment remain. Further investigations on this topic are recommended.