Compressed SENSE in Pediatric Brain Tumor MR Imaging

Purpose To compare the image quality, examination time, and total energy release of a standardized pediatric brain tumor magnetic resonance imaging (MRI) protocol performed with and without compressed sensitivity encoding (C-SENSE). Recently introduced as an acceleration technique in MRI, we hypothesized that C‑SENSE would improve image quality, reduce the examination time and radiofrequency-induced energy release compared with conventional examination in a pediatric brain tumor protocol. Methods This retrospective study included 22 patients aged 2.33–18.83 years with different brain tumor types who had previously undergone conventional MRI examination and underwent follow-up C‑SENSE examination. Both examinations were conducted with a 3.0-Tesla device and included pre-contrast and post-contrast T1-weighted turbo-field-echo, T2-weighted turbo-spin-echo, and fluid-attenuated inversion recovery sequences. Image quality was assessed in four anatomical regions of interest (tumor area, cerebral cortex, basal ganglia, and posterior fossa) using a 5-point scale. Reader preference between the standard and C‑SENSE images was evaluated. The total examination duration and energy deposit were compared based on scanner log file analysis. Results Relative to standard examinations, C‑SENSE examinations were characterized by shorter total examination times (26.1 ± 3.93 vs. 22.18 ± 2.31 min; P = 0.001), reduced total energy deposit (206.0 ± 19.7 vs. 92.3 ± 18.2 J/kg; P < 0.001), and higher image quality (overall P < 0.001). Conclusion C‑SENSE contributes to the improvement of image quality, reduction of scan times and radiofrequency-induced energy release relative to the standard protocol in pediatric brain tumor MRI.

Deficiency in the Treatment Description of mTOR Inhibitor Resistance in Medulloblastoma, a Systematic Review

Medulloblastoma is a common fatal pediatric brain tumor. More treatment options are required to prolong survival and decrease disability. mTOR proteins play an essential role in the disease pathogenesis, and are an essential target for therapy. Three generations of mTOR inhibitors have been developed and are clinically used for immunosuppression and chemotherapy for multiple cancers. Only a few mTOR inhibitors have been investigated for the treatment of medulloblastoma and other pediatric tumors. The first-generation mTOR, sirolimus, temsirolimus, and everolimus, went through phase I clinical trials. The second-generation mTOR, AZD8055 and sapanisertib, suppressed medulloblastoma cell growth; however, limited studies have investigated possible resistance pathways. No clinical trials have been found to treat medulloblastoma using third-generation mTOR inhibitors. This systematic review highlights the mechanisms of resistance of mTOR inhibitors in medulloblastoma and includes IDO1, T cells, Mnk2, and eIF4E, as they prolong malignant cell survival. The findings promote the importance of combination therapy in medulloblastoma due to its highly resistant nature.

Longitudinal Changes in Brain Diffusion MRI Indices during and after Proton Beam Therapy in a Child with Pilocytic Astrocytoma: A Case Report

Proton beam therapy (PBT) is an effective pediatric brain tumor treatment. However, the resulting microstructural changes within and around irradiated tumors are unknown. We retrospectively applied diffusion tensor imaging (DTI) and free-water imaging (FWI) on diffusion-weighted magnetic resonance imaging (dMRI) data to monitor microstructural changes during the PBT and after 8 months in a pilocytic astrocytoma (PA) and normal-appearing white matter (NAWM). We evaluated the conventional MRI- and dMRI-derived indices from six MRI sessions (t0–t5) in a Caucasian child with a hypothalamic PA: at baseline (t0), during the PBT (t1–t4) and after 8 months (t5). The tumor voxels were classified as “solid” or “fluid” based on the FWI. While the tumor volume remained stable during the PBT, the dMRI analyses identified two different response patterns: (i) an increase in fluid content and diffusivity with anisotropy reductions in the solid voxels at t1, followed by (ii) smaller variations in fluid content but higher anisotropy in the solid voxels at t2–t4. At follow-up (t5), the tumor volume, fluid content, and diffusivity in the solid voxels increased. The NAWM showed dose-dependent microstructural changes. The use of the dMRI and FWI showed complex dynamic microstructural changes in the irradiated mass during the PBT and at follow-up, opening new avenues in our understanding of radiation-induced pathophysiologic mechanisms in tumors and the surrounding tissues.

Nuchal Skinfold Thickness in Pediatric Brain Tumor Patients

BackgroundSevere obesity and tumor relapse/progression have impact on long-term prognosis in pediatric brain tumor patients.MethodsIn a cross-sectional study, we analyzed nuchal skinfold thickness (NST) on magnetic-resonance imaging (MRI) follow-up monitoring as a parameter for assessment of nuchal adipose tissue in 177 brain tumor patients (40 World Health Organization (WHO) grade 1–2 brain tumor; 31 grade 3–4 brain tumor; 106 craniopharyngioma), and 53 healthy controls. Furthermore, body mass index (BMI), waist-to-height ratio, caliper-measured skinfold thickness, and blood pressure were analyzed for association with NST.ResultsCraniopharyngioma patients showed higher NST, BMI, waist-to-height ratio, and caliper-measured skinfold thickness when compared to other brain tumors and healthy controls. WHO grade 1–2 brain tumor patients were observed with higher BMI, waist circumference and triceps caliper-measured skinfold thickness when compared to WHO grade 3–4 brain tumor patients. NST correlated with BMI, waist-to-height ratio, and caliper-measured skinfold thickness. NST, BMI and waist-to-height ratio were associated with increased blood pressure. In craniopharyngioma patients with hypothalamic involvement/lesion or gross-total resection, rate and degree of obesity were increased.ConclusionsNST could serve as a novel useful marker for regional nuchal adipose tissue. NST is highly associated with body mass and waist-to-height ratio, and easily measurable in routine MRI monitoring of brain tumor patients.

Educational Pain Points for Pediatric Brain Tumor Survivors: Review of Risks and Remedies

Evolving treatment paradigms have led to increased survival rates for children diagnosed with a brain tumor, and this has increasingly shifted clinical and research focus to morbidity and quality of life among survivors. Among unfavorable outcomes, survivors of pediatric brain tumors are at risk for academic failure and low educational attainment, which may then contribute to lower health related quality of life, lower income and vocational status, and a greater likelihood of dependence on others in adulthood. Several specific risk factors for lower educational performance and attainment have been investigated. These are typically examined in isolation from one another which clouds understanding of the full range and potential interplay of contributors to educational difficulties. This review integrates and summarizes what is known about the direct and indirect barriers to educational success and performance (i.e., educational pain points) to enhance clinician knowledge of factors to consider when working with pediatric brain tumor survivors. Specific barriers to educational success include neurocognitive difficulties, school absences, psychosocial challenges, challenges to knowledge and communication, and physical and sensory difficulties. Finally, we discuss the current state of educational interventions and supports and offer recommendations for future research to improve educational outcomes for pediatric brain tumor survivors.

Effects of Sleep Disturbance on Neuropsychological Functioning in Patients with Pediatric Brain Tumor

Purpose While the effects of sleep on cognition in typically developing children are well established, there is a paucity of research in patients with pediatric brain tumor (PBT), despite their increased risk for sleep-related disturbances. The aim of this study was to examine the impact of sleep factors on patient-reported outcome (PRO) measures, including adaptive and executive functioning within this population.Methods 133 patients with PBT (52% male) ages 5-23 (x̄ = 12.8yrs; SD = 4.5yrs) underwent neuropsychological evaluation, including assessment of adaptive and executive functioning. Subjective sleep concerns, nocturnal sleep duration, and daytime sleep behavior were also collected and compared to age-based guidelines.Results Nearly 30% of patients reported subjective sleep concerns, while the sample as a whole presented with reduced nocturnal sleep duration (approximately one hour below age-based recommendations). Despite the expectation for monophasic sleep by age five, nearly half of the sample reported consistent daytime napping. With regard to functional outcomes, inadequate sleep predicted decreased adaptive functioning, F(1, 56) = 4.23, p < .05 (R2 = .07), as well as increased symptoms of executive dysfunction, F(1, 108) = 3.51, p < .05 (R2 = .03).Conclusion Patients with PBT demonstrate several aspects of abnormal sleep, which are associated with poorer long-term PROs. Further exploration of diagnostic, treatment-related, and demographic variables will be needed to better understand these relationships among patients with PBT in order to inform appropriate interventions.

Brain tumors in the first two years of life

Background Brain tumors in the first years of life are frequently encountered recently with the advancement in neuroimaging, neurosurgery and neuroanethesia where early diagnosis of these lesions became available even before birth. Their management is challenging where the surgery is technically demanding, radiotherapy is omitted in this age because of its late sequelae and chemotherapy role may be beneficial, but it is limited also by its side effects and neurotoxicity. The aim of this article is to review the current literature about the brain tumors in the first two years of life, their diagnosis and treatment. Main body Brain tumors in the first two years of life encompass mainly fetal/congenital tumors and infantile tumors. They account for 1.4–18% of cases of pediatric brain tumor, and most of them are diagnosed in the first year of life. The main histopathologies diagnosed are glial tumors, choroid plexus tumors, medulloblastoma and other embryonal tumors, teratoma and ependymoma. They are mainly supratentorial. Large head and bulging fontanelles are the main presenting symptoms and signs secondary to increased intracranial pressure secondary to large tumors or associated hydrocephalus. Prenatal and postnatal ultrasonography represents the initial imaging step in the diagnosis that should be complemented by MRI and CT brain. The main and first line of treatment of infantile brain tumors is surgical excision as the prognosis is directly related to the extent of resection besides surgery offers specimens for histopathological diagnosis and adjuvant chemotherapy is given for residual irresectable cases and malignant tumors with the main aim to delay radiotherapy beyond the age of three years. Conclusion Brain tumors in the first two years of life are a challenging group of different histopathological entities with underlying specific molecular characterization and genetic predispositions. They have aggressive behavior and general poor prognosis with limited options of management. Individualized multidisciplinary management for each case is needed, and future studies for therapeutic medications targeting underlying molecular biology may improve their outcome.