Upper extremity neuromonitoring changes are more common than lower extremity during spinal fusion for Scheuermann's kyphosis.

INTRODUCTION: The purpose of this study is to determine the incidence of intraoperative neuromonitoring (IONM) changes and postoperative neurologic deficit in patients with Scheuermann's Kyphosis (SK) undergoing posterior spinal fusion (PSF). METHODS: Single-center, retrospective chart review of the clinical, surgical and IONM data (somatosensory evoked potential (SSEP) and neurogenic motor evoked potential (NMEP) or transcranial motor evoked potential (TcMEP)) from patients with SK undergoing PSF at our center from 1993 to 2021. RESULTS: One hundred and four SK patients (mean 16.4 ± 1.9 years) underwent PSF with correction of kyphosis from mean 79.4 ± 10.8° to 35.4 ± 13.9°. MEP data were obtained using either NMEP in 34.6% of patients) or TcMEP in 65.4% of patients. Only 3.8% of cases had lower extremity (LE) IONM changes during surgery, with no postoperative neurologic deficits in those patients. IONM changes occurred more frequently in the upper extremities (UE) with 14 (13.4%) patients having changes in UE SSEPs. Patients with UE IONM changes had significantly longer surgical times (p = 0.0096) and higher number of levels fused (p = 0.003) compared to patients without changes. Their weight, but not BMI, was also significantly higher (p = 0.036). These UE IONM changes resolved with arm repositioning in all but one patient who had a postoperative UE neurapraxia that resolved by 6 weeks. There was 1 postoperative transient femoral nerve palsy without IONM changes thought to be due to patient positioning. CONCLUSION: The incidence of critical LE IONM changes during PSF for SK is 3.4%, which is similar to that reported in AIS. UE IONM changes are significantly more common at 13.4%, revealing that these patients are vulnerable to malpositioning of the arms during surgery.

Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial.

OBJECTIVE: To evaluate the long-term safety and efficacy of add-on cannabidiol (CBD) in patients with seizures associated with tuberous sclerosis complex (TSC) in the open-label extension (OLE) of the randomized, placebo-controlled phase 3 trial GWPCARE6 (NCT02544763). Results of an interim (February 2019 data cut) analysis are reported. METHODS: Patients who completed the randomized trial enrolled to receive CBD (Epidiolex® in the United States; Epidyolex® in the EU; 100 mg/mL oral solution). The initial target dose was 25 mg/kg/day, which, based on response and tolerability, could be decreased or increased up to 50 mg/kg/day. The primary end point was safety. Key secondary end points included percentage reduction in TSC-associated (countable focal and generalized) seizures, responder rates, and Subject/Caregiver Global Impression of Change (S/CGIC). RESULTS: Of 201 patients who completed the randomized phase, 199 (99%) entered the OLE. Mean age was 13 years (range, 1-57). At the time of analysis, 5% of patients had completed treatment, 20% had withdrawn, and 75% were ongoing. One-year retention rate was 79%. Median treatment time was 267 days (range, 18-910) at a 27 mg/kg/day mean modal dose. Most patients (92%) had an adverse event (AE). Most common AEs were diarrhea (42%), seizure (22%), and decreased appetite (20%). AEs led to permanent discontinuation in 6% of patients. There was one death that was deemed treatment unrelated by the investigator. Elevated liver transaminases occurred in 17 patients (9%) patients; 12 were taking valproate. Median percentage reductions in seizure frequency (12-week windows across 48 weeks) were 54%-68%. Seizure responder rates (≥50%, ≥75%, 100% reduction) were 53%-61%, 29%-45%, and 6%-11% across 12-week windows for 48 weeks. Improvement on the S/CGIC scale was reported by 87% of patients/caregivers at 26 weeks. SIGNIFICANCE: In patients with TSC, long-term add-on CBD treatment was well tolerated and sustainably reduced seizures through 48 weeks, with most patients/caregivers reporting global improvement.

Use of transcranial motor-evoked potentials to provide reliable intraoperative neuromonitoring for the Charcot-Marie-Tooth population undergoing spine deformity surgery.

PURPOSE: Intraoperative neuromonitoring (IONM) has historically been difficult to obtain in patients with Charcot-Marie-Tooth (CMT) disease. Transcranial motor-evoked potentials (TcMEPs) have been found to be safe and effective for other spinal deformity patients. Our objective was to determine the effectiveness of TcMEP monitoring in patients with CMT. METHODS: An IRB-approved, retrospective review of CMT patients undergoing spinal deformity surgery assessing TcMEP, somatosensory-evoked potential (SSEP), and neurogenic motor evoked potential (NMEP) IONM was performed. A 2:1 matched cohort control group of idiopathic spinal deformity patients was used. A waveform grading system was applied to review baseline TcMEP reliability and quality, which was validated via intraclass correlation coefficient amongst five raters. RESULTS: Twenty-three CMT patients (26 surgical cases) were identified. The use of TcMEP improved the ability to obtain baseline IONM when compared to SSEP (83% vs. 20%; p < 0.001) and NMEP (83% vs. 18%; p = 0.003). Baseline monitoring was obtained less often for CMT patients using SSEP (20% vs. 100%; p < 0.001) and TcMEP (83% vs. 100%; p = 0.111) compared to idiopathic patients. Sweep length (time from stimulation waveform evaluation) and maximum stimulation voltage were higher in the CMT group (289 ms vs. 111 ms p = 0.007 and 740 V vs. 345 V p = 0.089, respectively). CONCLUSION: TcMEP monitoring significantly improves the ability to provide IONM for CMT patients undergoing spinal deformity surgery. Utilizing longer sweep lengths enhances the ability to attain baseline TcMEP readings, allowing surgeons to more safely proceed with surgery for these complex patients. LEVEL OF EVIDENCE: Therapeutic-Level III.

Multivariate data analysis identifies natural clusters of Tuberous Sclerosis Complex Associated Neuropsychiatric Disorders (TAND).

BACKGROUND: Tuberous Sclerosis Complex (TSC), a multi-system genetic disorder, is associated with a wide range of TSC-Associated Neuropsychiatric Disorders (TAND). Individuals have apparently unique TAND profiles, challenging diagnosis, psycho-education, and intervention planning. We proposed that identification of natural TAND clusters could lead to personalized identification and treatment of TAND. Two small-scale studies showed cluster and factor analysis could identify clinically meaningful natural TAND clusters. Here we set out to identify definitive natural TAND clusters in a large, international dataset. METHOD: Cross-sectional, anonymized TAND Checklist data of 453 individuals with TSC were collected from six international sites. Data-driven methods were used to identify natural TAND clusters. Mean squared contingency coefficients were calculated to produce a correlation matrix, and various cluster analyses and exploratory factor analysis were examined. Statistical robustness of clusters was evaluated with 1000-fold bootstrapping, and internal consistency calculated with Cronbach's alpha. RESULTS: Ward's method rendered seven natural TAND clusters with good robustness on bootstrapping. Cluster analysis showed significant convergence with an exploratory factor analysis solution, and, with the exception of one cluster, internal consistency of the emerging clusters was good to excellent. Clusters showed good clinical face validity. CONCLUSIONS: Our findings identified a data-driven set of natural TAND clusters from within highly variable TAND Checklist data. The seven natural TAND clusters could be used to train families and professionals and to develop tailored approaches to identification and treatment of TAND. Natural TAND clusters may also have differential aetiological underpinnings and responses to molecular and other treatments.

Updated International Tuberous Sclerosis Complex Diagnostic Criteria and Surveillance and Management Recommendations.

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disease affecting multiple body systems with wide variability in presentation. In 2013, Pediatric Neurology published articles outlining updated diagnostic criteria and recommendations for surveillance and management of disease manifestations. Advances in knowledge and approvals of new therapies necessitated a revision of those criteria and recommendations. METHODS: Chairs and working group cochairs from the 2012 International TSC Consensus Group were invited to meet face-to-face over two days at the 2018 World TSC Conference on July 25 and 26 in Dallas, TX, USA. Before the meeting, working group cochairs worked with group members via e-mail and telephone to (1) review TSC literature since the 2013 publication, (2) confirm or amend prior recommendations, and (3) provide new recommendations as required. RESULTS: Only two changes were made to clinical diagnostic criteria reported in 2013: "multiple cortical tubers and/or radial migration lines" replaced the more general term "cortical dysplasias," and sclerotic bone lesions were reinstated as a minor criterion. Genetic diagnostic criteria were reaffirmed, including highlighting recent findings that some individuals with TSC are genetically mosaic for variants in TSC1 or TSC2. Changes to surveillance and management criteria largely reflected increased emphasis on early screening for electroencephalographic abnormalities, enhanced surveillance and management of TSC-associated neuropsychiatric disorders, and new medication approvals. CONCLUSIONS: Updated TSC diagnostic criteria and surveillance and management recommendations presented here should provide an improved framework for optimal care of those living with TSC and their families.

Epilepsy and Electroencephalographic Abnormalities in SATB2-Associated Syndrome.

BACKGROUND: Seizures are an under-reported feature of the SATB2-associated syndrome phenotype. We describe the electroencephalographic findings and seizure semiology and treatment in a population of individuals with SATB2-associated syndrome. METHODS: We performed a retrospective review of 101 individuals with SATB2-associated syndrome who were reported to have had a previous electroencephalographic study to identify those who had at least one reported abnormal result. For completeness, a supplemental survey was distributed to the caregivers and input from the treating neurologist was obtained whenever possible. RESULTS: Forty-one subjects were identified as having at least one prior abnormal electroencephalography. Thirty-eight individuals (93%) had epileptiform discharges, 28 (74%) with central localization. Sleep stages were included as part of the electroencephalographies performed in 31 individuals (76%), and epileptiform activity was recorded during sleep in all instances (100%). Definite clinical seizures were diagnosed in 17 individuals (42%) with a mean age of onset of 3.2 years (four months to six years), and focal seizures were the most common type of seizure observed (42%). Six subjects with definite clinical seizures needed polytherapy (35%). Delayed myelination and/or abnormal white matter hyperintensities were seen on neuroimaging in 19 individuals (61%). CONCLUSIONS: Epileptiform abnormalities are commonly seen in individuals with SATB2-associated syndrome. A baseline electroencephalography that preferably includes sleep stages is recommended during the initial evaluation of all individuals with SATB2-associated syndrome, regardless of clinical suspicion of epilepsy.

Pharmacokinetics and Tolerability of Multiple Doses of Pharmaceutical-Grade Synthetic Cannabidiol in Pediatric Patients with Treatment-Resistant Epilepsy.

BACKGROUND: Prior studies have evaluated the use of various constituents of cannabis for their anti-seizure effects. Specifically, cannabidiol, a non-psychoactive component of cannabis, has been investigated for treatment-resistant epilepsy, but more information is needed particularly on its use in a pediatric population. OBJECTIVE: The objective of this study was to evaluate the pharmacokinetics and safety of a synthetic pharmaceutical-grade cannabidiol oral solution in pediatric patients with treatment-resistant epilepsy. METHODS: In this open-label study, pediatric patients (aged 1 to ≤ 17 years) with treatment-resistant epilepsy received cannabidiol oral solution administered as add-on to their current antiepileptic drug regimen. Patients received a single dose (5, 10, or 20 mg/kg) on day 1 and twice-daily dosing on days 4 through 10 (10-mg/kg [cohort 1], 20-mg/kg [cohort 2], or 40-mg/kg [cohort 3] total daily dose). Serial blood samples were collected on day 1 before dosing and up to 72 h post-dose, and on day 10 before dosing and up to 24 h post-dose. Blood samples to assess trough concentrations of cannabidiol were collected on day 6 (for patients aged 12 to ≤ 17 years), day 8 (for patients aged 2 to ≤ 17 years), and day 9 (for patients aged 6 to ≤ 17 years). RESULTS: Overall, 61 patients across three cohorts received one of three doses of cannabidiol oral solution (mean age, 7.6 years). The age composition was similar in the three cohorts. There was a trend for increased cannabidiol exposure with increased cannabidiol oral solution dosing, but overall exposure varied. Approximately 2-6 days of twice-daily dosing provided steady-state concentrations of cannabidiol. A bi-directional drug interaction occurred with cannabidiol and clobazam. Concomitant administration of clobazam with 40 mg/kg/day of cannabidiol oral solution resulted in a 2.5-fold increase in mean cannabidiol exposure. Mean plasma clobazam concentrations were 1.7- and 2.2-fold greater in patients receiving clobazam concomitantly with 40 mg/kg/day of cannabidiol oral solution compared with 10 mg/kg/day and 20 mg/kg/day. Mean plasma norclobazam values were 1.3- and 1.9-fold higher for patients taking clobazam plus 40 mg/kg/day of cannabidiol oral solution compared with the 10-mg/kg/day and 20-mg/kg/day groups. All doses were generally well tolerated, and common adverse events that occurred at > 10% were somnolence (21.3%), anemia (18.0%), and diarrhea (16.4%). CONCLUSIONS: Inter-individual variability in systemic cannabidiol exposure after pediatric patient treatment with cannabidiol oral solution was observed but decreased with multiple doses. Short-term administration was generally safe and well tolerated. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02324673).

Mutation update for the SATB2 gene.

SATB2-associated syndrome (SAS) is an autosomal dominant neurodevelopmental disorder caused by alterations in the SATB2 gene. Here we present a review of published pathogenic variants in the SATB2 gene to date and report 38 novel alterations found in 57 additional previously unreported individuals. Overall, we present a compilation of 120 unique variants identified in 155 unrelated families ranging from single nucleotide coding variants to genomic rearrangements distributed throughout the entire coding region of SATB2. Single nucleotide variants predicted to result in the occurrence of a premature stop codon were the most commonly seen (51/120 = 42.5%) followed by missense variants (31/120 = 25.8%). We review the rather limited functional characterization of pathogenic variants and discuss current understanding of the consequences of the different molecular alterations. We present an expansive phenotypic review along with novel genotype-phenotype correlations. Lastly, we discuss current knowledge of animal models and present future prospects. This review should help provide better guidance for the care of individuals diagnosed with SAS.

Epilepsy treatment patterns among patients with tuberous sclerosis complex.

INTRODUCTION: Tuberous sclerosis complex (TSC) is a rare congenital disorder often associated with epilepsy. However, real-world treatment patterns for epilepsy in patients with TSC are not yet well categorized. METHODS: This study included patients with TSC and epilepsy from fifteen clinics in the United States and one in Belgium who were enrolled in the TSC Natural History Database (2006-2014). Patient demographics and epilepsy treatment patterns, including the use of anti-epileptic drugs (AEDs), epilepsy surgeries, and dietary therapies were assessed. RESULTS: Of the 1328 patients with TSC in the database, 1110 (83.6%) were diagnosed with epilepsy. The median age of epilepsy diagnosis was 0.7 years. Of those who received treatment for epilepsy (92.3%), 99.5% were prescribed AEDs, 25.3% underwent surgery, 7.9% were prescribed special diets, and 1% were prescribed mammalian target of rapamycin (mTOR) inhibitors. Of the patients receiving AEDs, over half (64.5%) used ≥3 different AEDs, and 22.5% underwent surgical treatment following AED initiation. Of the patients who underwent surgery, 35.1% had subsequent surgery. CONCLUSION: The use of multiple AEDs and surgical interventions may indicate a need for new therapies to reduce the treatment burden among patients with TSC and epilepsy.

The effect of everolimus on renal angiomyolipoma in pediatric patients with tuberous sclerosis being treated for subependymal giant cell astrocytoma.

BACKGROUND: Patients with tuberous sclerosis complex (TSC) often have multiple TSC-associated hamartomas, particularly in the brain and kidney. METHODS: This was a post hoc analysis of pediatric patients being treated for subependymal giant cell astrocytomas (SEGAs) during the phase 3, randomized, double-blind, placebo-controlled EXIST-1 trial. Patients were initially randomly assigned to receive everolimus 4.5 mg/m2/day (target blood trough 5-15 mg/dl) or placebo and could continue in an open-label extension phase. Angiomyolipoma response rates were analyzed in patients aged <18 years with ≥1 target angiomyolipoma lesion at baseline. Response was defined as the proportion of patients with a ≥50% reduction in the sum volume of target renal angiomyolipomata from baseline, in the absence of new target angiomyolipomata, a >20% increase in kidney volume from nadir, and angiomyolipoma-related bleeding ≥ grade 2. Tolerability was also assessed. RESULTS: Overall, this analysis included 33 patients. Renal angiomyolipoma response was achieved by 75.8% of patients (95% confidence interval, 57.7-88.9%), with sustained mean reductions in renal angiomyolipoma volume over nearly 4 years of treatment. In addition, most (≥80%) achieved clinically relevant reductions in angiomyolipoma volume (≥50%), beginning at week 24 and continuing for the remainder of the study. Everolimus was generally well tolerated in this subgroup, with most adverse events being grade 1 or 2 in severity. CONCLUSIONS: Although everolimus is currently not indicated for this use, this analysis from EXIST-1 demonstrates its long-term efficacy and safety for the treatment of renal angiomyolipoma in pediatric patients undergoing treatment for TSC-associated SEGA.

Pooled analysis of menstrual irregularities from three major clinical studies evaluating everolimus for the treatment of tuberous sclerosis complex.

OBJECTIVES: To determine the impact of everolimus on female fertility, including menstrual irregularities, secondary amenorrhea, and luteinizing and follicle stimulating hormone levels in female patients. DESIGN: A pooled analysis from 3 prospective studies consisting of a core phase (≥6 months) and a long-term follow-up open-label extension. SETTING: One phase 2 single-center and two phase 3 multicenter studies. PARTICIPANTS: Data were obtained from female participants, restricted to those between 10 and 55 years of age, during 1 of 3 of the described clinical trials of everolimus. Patients had received ≥ 1 dose of everolimus. MAIN OUTCOME MEASURES: Incidence of fertility events. RESULTS: A total of 43/112 patients (38.4%) experienced at least 1 menstrual irregularity. The most common events were amenorrhea (24.1%) and irregular menstruation (17.0%). Seven patients (6.3%) experienced grade 3/4 amenorrhea. When only the longest duration period of amenorrhea for each patient was considered, the median duration was 291 days. Fifteen patients attained menarche during the treatment period in any of the pooled studies. The mean age of menarche for this group was 12.4 years, similar to that of patients who were postmenarche at study entry (12.2 years). A total of 19/92 patients (20.7%) who were postmenarche at baseline or during the study experienced an irregular menstruation event. An increased luteinizing hormone level was reported as an adverse event in 3/112 patients (3%), and follicle-stimulating hormone levels were within normal limits for these patients. CONCLUSIONS: No new safety concerns emerged regarding endocrine function and menstruation in female patients with tuberous sclerosis complex-associated subependymal giant cell astrocytoma or angiomyolipoma, who were receiving everolimus. TRIAL REGISTRATION: ClinicalTrials.gov NCT00411619, NCT00789828, NCT00790400.

Biallelic mutations in the ferredoxin reductase gene cause novel mitochondriopathy with optic atrophy.

Iron-sulfur (Fe-S) clusters are ubiquitous cofactors essential to various cellular processes, including mitochondrial respiration, DNA repair, and iron homeostasis. A steadily increasing number of disorders are being associated with disrupted biogenesis of Fe-S clusters. Here, we conducted whole-exome sequencing of patients with optic atrophy and other neurological signs of mitochondriopathy and identified 17 individuals from 13 unrelated families with recessive mutations in FDXR, encoding the mitochondrial membrane-associated flavoprotein ferrodoxin reductase required for electron transport from NADPH to cytochrome P450. In vitro enzymatic assays in patient fibroblast cells showed deficient ferredoxin NADP reductase activity and mitochondrial dysfunction evidenced by low oxygen consumption rates (OCRs), complex activities, ATP production and increased reactive oxygen species (ROS). Such defects were rescued by overexpression of wild-type FDXR. Moreover, we found that mice carrying a spontaneous mutation allelic to the most common mutation found in patients displayed progressive gait abnormalities and vision loss, in addition to biochemical defects consistent with the major clinical features of the disease. Taken together, these data provide the first demonstration that germline, hypomorphic mutations in FDXR cause a novel mitochondriopathy and optic atrophy in humans.

Patterns of Disease Monitoring and Treatment Among Patients With Tuberous Sclerosis Complex-related Angiomyolipomas.

OBJECTIVE: To use the tuberous sclerosis complex (TSC) Natural History Database to describe monitoring and treatment patterns among patients with TSC-related angiomyolipomas (AMLs). METHODS: This study used the TSC Natural History Database, which contains demographics, affected areas, diagnosis, and treatments for more than 1300 patients with TSC enrolled in 16 participating clinics during 2006-2013. Patient characteristics, AML monitoring tests, and AML treatments were assessed. RESULTS: Among the 621 patients with TSC-related AMLs, 54% were female; 77% were Caucasian. Median age at TSC diagnosis was <1 year, whereas median age at AML diagnosis was 9.8 years. Most patients (84%) had at least 1 monitoring test following AML diagnosis. The most commonly used tests were magnetic resonance imaging (MRI; 65% of patients), ultrasound (62%), and computed tomography (41%). Between 2000 and 2012, MRI made up an increasingly large proportion of the total number of monitoring tests. Once diagnosed, 155 (25%) of patients received treatment for AML. The median time from diagnosis to first treatment was 3.8 years. The most common treatments were embolization (10%), everolimus (9%), sirolimus (6%), and nephrectomy (6%). The rate of nephrectomies declined over time, with none conducted during 2011 and 2012. No subsequent surgeries were reported among the 71 patients who received mTOR inhibitor as first-line therapy. CONCLUSION: The use of MRIs increased between 2000 and 2012 among patients with TSC-AML. The majority of these patients did not receive treatment for AML. Use of nephrectomy decreased over the study period and was particularly rare in patients who received an mTOR inhibitor.

TSC2 c.1864C>T variant associated with mild cases of tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is an autosomal dominantly inherited disorder with variable expressivity associated with hamartomatous tumors, abnormalities of the skin, and neurologic problems including seizures, intellectual disability, and autism. TSC is caused by pathogenic variants in either TSC1 or TSC2. In general, TSC2 pathogenic variants are associated with a more severe phenotype than TSC1 pathogenic variants. Here, we report a pathogenic TSC2 variant, c.1864C>T, p.(Arg622Trp), associated with a mild phenotype, with most carriers meeting fewer than two major clinical diagnostic criteria for TSC. This finding has significant implications for counseling patients regarding prognosis. More patient data are required before changing the surveillance recommendations for patients with the reported variant. However, consideration should be given to tailoring surveillance recommendations for all pathogenic TSC1 and TSC2 variants with documented milder clinical sequelae. © 2017 Wiley Periodicals, Inc.

Long-Term Use of Everolimus in Patients with Tuberous Sclerosis Complex: Final Results from the EXIST-1 Study.

BACKGROUND: Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, has demonstrated efficacy in treating subependymal giant cell astrocytomas (SEGAs) and other manifestations of tuberous sclerosis complex (TSC). However, long-term use of mTOR inhibitors might be necessary. This analysis explored long-term efficacy and safety of everolimus from the conclusion of the EXIST-1 study (NCT00789828). METHODS AND FINDINGS: EXIST-1 was an international, prospective, double-blind, placebo-controlled phase 3 trial examining everolimus in patients with new or growing TSC-related SEGA. After a double-blind core phase, all remaining patients could receive everolimus in a long-term, open-label extension. Everolimus was initiated at a dose (4.5 mg/m2/day) titrated to a target blood trough of 5-15 ng/mL. SEGA response rate (primary end point) was defined as the proportion of patients achieving confirmed ≥50% reduction in the sum volume of target SEGA lesions from baseline in the absence of worsening nontarget SEGA lesions, new target SEGA lesions, and new or worsening hydrocephalus. Of 111 patients (median age, 9.5 years) who received ≥1 dose of everolimus (median duration, 47.1 months), 57.7% (95% confidence interval [CI], 47.9-67.0) achieved SEGA response. Of 41 patients with target renal angiomyolipomas at baseline, 30 (73.2%) achieved renal angiomyolipoma response. In 105 patients with ≥1 skin lesion at baseline, skin lesion response rate was 58.1%. Incidence of adverse events (AEs) was comparable with that of previous reports, and occurrence of emergent AEs generally decreased over time. The most common AEs (≥30% incidence) suspected to be treatment-related were stomatitis (43.2%) and mouth ulceration (32.4%). CONCLUSIONS: Everolimus use led to sustained reduction in tumor volume, and new responses were observed for SEGA and renal angiomyolipoma from the blinded core phase of the study. These findings support the hypothesis that everolimus can safely reverse multisystem manifestations of TSC in a significant proportion of patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT00789828.

Electromagnetic interference in intraoperative monitoring of motor evoked potentials and a wireless solution.

Intraoperative neurophysiological monitoring (IONM) is utilized to minimize neurological morbidity during spine surgery. Transcranial motor evoked potentials (TcMEPs) are principal IONM signals in which the motor cortex of the subject is stimulated with electrical pulses and the evoked potentials are recorded from the muscles of interest. Currently available monitoring systems require the connection of 40-60 lengthy lead wires to the patient. These wires contribute to a crowded and cluttered surgical environment, and limit the maneuverability of the surgical team. In this work, it was demonstrated that the cumbersome wired system is vulnerable to electromagnetic interference (EMI) produced by operating room (OR) equipment. It was hypothesized that eliminating the lengthy recording wires can remove the EMI induced in the IONM signals. Hence, a wireless system to acquire TcMEPs was developed and validated through bench-top and animal experiments. Side-by-side TcMEPs acquisition from the wired and wireless systems in animal experiments under controlled conditions (absence of EMI from OR equipment) showed comparable magnitudes and waveforms, thus demonstrating the fidelity in the signal acquisition of the wireless solution. The robustness of the wireless system to minimize EMI was compared with a wired-system under identical conditions. Unlike the wired-system, the wireless system was not influenced by the electromagnetic waves from the C-Arm X-ray machine and temperature management system in the OR.

Variants Within TSC2 Exons 25 and 31 Are Very Unlikely to Cause Clinically Diagnosable Tuberous Sclerosis.

Inactivating mutations in TSC1 and TSC2 cause tuberous sclerosis complex (TSC). The 2012 international consensus meeting on TSC diagnosis and management agreed that the identification of a pathogenic TSC1 or TSC2 variant establishes a diagnosis of TSC, even in the absence of clinical signs. However, exons 25 and 31 of TSC2 are subject to alternative splicing. No variants causing clinically diagnosed TSC have been reported in these exons, raising the possibility that such variants would not cause TSC. We present truncating and in-frame variants in exons 25 and 31 in three individuals unlikely to fulfil TSC diagnostic criteria and examine the importance of these exons in TSC using different approaches. Amino acid conservation analysis suggests significantly less conservation in these exons compared with the majority of TSC2 exons, and TSC2 expression data demonstrates that the majority of TSC2 transcripts lack exons 25 and/or 31 in many human adult tissues. In vitro assay of both exons shows that neither exon is essential for TSC complex function. Our evidence suggests that variants in TSC2 exons 25 or 31 are very unlikely to cause classical TSC, although a role for these exons in tissue/stage specific development cannot be excluded.

Everolimus for subependymal giant cell astrocytoma in patients with tuberous sclerosis complex: 2-year open-label extension of the randomised EXIST-1 study.

BACKGROUND: In the EXIST-1 trial, initiated on Aug 10, 2009, more than 35% of patients with subependymal giant cell astrocytoma (SEGA) associated with tuberous sclerosis complex had at least 50% reduction in SEGA volume after 9·6 months of treatment with everolimus. In this Article, we report interim data (up to Jan 11, 2013) to support longer-term tolerability and efficacy of everolimus from the continuing 4-year extension phase of EXIST-1. METHODS: We assessed data from a prospective, open-label extension of a multicentre, phase 3, randomised, double-blind, placebo-controlled study in patients with tuberous sclerosis complex who had SEGA that was growing and needed treatment. In this extension study, we included all patients who had been assigned everolimus during the double-blind, randomised phase of the trial and those patients who crossed over from the placebo group to receive everolimus during the randomised phase or at the start of the extension phase. All patients received oral everolimus at a starting dose of 4·5 mg/m(2) per day. Everolimus dose was subsequently adjusted subject to tolerability to attain blood trough concentrations of 5-15 ng/mL. An independent central radiology review team assessed SEGA response (at least a 50% reduction from baseline in total volume of all target SEGAs; the primary endpoint) by MRI at 12, 24, and 48 weeks, then every year thereafter in all patients who received at least one dose of everolimus. This study was registered with ClinicalTrials.gov, number NCT00789828. FINDINGS: Of the original 117 randomly assigned patients, 111 were given everolimus between Aug 20, 2009, and Jan 11, 2013 (date of data cutoff); we included these patients in our longer-term analysis. Median duration of everolimus exposure was 29·3 months (IQR 19·4-33·8). Median follow-up was 28·3 months (IQR 19·3-33·0). 54 (49%) patients had a response of 50% or greater reduction in SEGA volume (95% CI 39·0-58·3), and duration of response was between 2·1 and 31·1 months (median not reached). SEGA volume was reduced by 50% or more in 39 (37%) of 105 patients at 24 weeks, 48 (46%) of 104 patients at 48 weeks, 36 (47%) of 76 patients at 96 weeks, and 11 (38%) of 29 patients at 144 weeks. Stomatitis (48 [43%] patients) and mouth ulceration (33 [30%] patients) were the most frequent treatment-related adverse events; infections were the most commonly reported treatment-related serious adverse event, occurring in 15 (14%) patients. 35 (32%) patients reported treatment-related grade 3 or 4 adverse events, the most common of which were stomatitis (nine [8%]) and pneumonia (nine [8%]). 18 (16%) patients had treatment-related serious adverse events. Six (5%) patients withdrew because of adverse events. INTERPRETATION: These results support the longer-term use of everolimus in patients who have few treatment options and who need continued treatment for tuberous sclerosis complex and its varied manifestations. Reduction or stabilisation of tumour volume with everolimus will hopefully provide long-term clinical benefit in patients with SEGA. FUNDING: Novartis Pharmaceuticals.

Brain MRI abnormalities and spectrum of neurological and clinical findings in three patients with proximal 16p11.2 microduplication.

The phenotype of recurrent ∼600 kb microdeletion and microduplication on proximal 16p11.2 is characterized by a spectrum of neurodevelopmental impairments including developmental delay and intellectual disability, epilepsy, autism and psychiatric disorders which are all subject to incomplete penetrance and variable expressivity. A variety of brain MRI abnormalities were reported in patients with 16p11.2 rearrangements, but no systematic correlation has been studied among patients with similar brain anomalies, their neurodevelopmental and clinical phenotypes. We present three patients with the proximal 16p11.2 microduplication exhibiting significant developmental delay, anxiety disorder and other variable clinical features. Our patients have abnormal brain MRI findings of cerebral T2 hyperintense foci (3/3) and ventriculomegaly (2/3). The neuroradiological or neurological findings in two cases prompted an extensive diagnostic work-up. One patient has exhibited neurological regression and progressive vision impairment and was diagnosed with juvenile neuronal ceroid-lipofuscinosis. We compare the clinical course and phenotype of these patients in regard to the clinical significance of the cerebral lesions and the need for MRI surveillance. We conclude that in all three patients the lesions were not progressive, did not show any sign of malignant transformation and could not be correlated to specific clinical features. We discuss potential etiologic mechanisms that may include overexpression of genes within the duplicated region involved in control of cell proliferation and complex molecular mechanisms such as the MAPK/ERK pathway. Systematic studies in larger cohorts are needed to confirm our observation and to establish the prevalence and clinical significance of these neuroanatomical abnormalities in patients with 16p11.2 duplications.