What to do with an incidental finding of a fused sagittal suture: a modified Delphi study.

OBJECTIVE: As many as 5% of normocephalic children may have a prematurely fused sagittal suture, yet the clinical significance and best course of management of this finding remain unclear. Providers in the Synostosis Research Group were surveyed to create a multicenter consensus on an optimal treatment and monitoring algorithm for this condition. METHODS: A four-round modified Delphi method was utilized. The first two rounds consisted of anonymous surveys distributed to 10 neurosurgeons and 9 plastic surgeons with expertise in craniosynostosis across 9 institutions, and presented 3 patients (aged 3 years, 2 years, and 2 months) with incidentally discovered fused sagittal sutures, normal cephalic indices, and no parietal dysmorphology. Surgeons were queried about their preferred term for this entity and how best to manage these patients. Results were synthesized to create a treatment algorithm. The third and fourth feedback rounds consisted of open discussion of the algorithm until no further concerns arose. RESULTS: Most surgeons preferred the term "premature fusion of the sagittal suture" (93%). At the conclusion of the final round, all surgeons agreed to not operate on the 3- and 2-year-old patients unless symptoms of intracranial hypertension or papilledema were present. In contrast, 50% preferred to operate on the 2-month-old. However, all agreed to utilize shared decision-making, taking into account any concerns about future head shape and neurodevelopment. Panelists agreed that patients over 18 months of age without signs or symptoms suggesting elevated intracranial pressure (ICP) should not undergo surgical treatment. CONCLUSIONS: Through the Delphi method, a consensus regarding management of premature fusion of the sagittal suture was obtained from a panel of North American craniofacial surgeons. Without signs or symptoms of ICP elevation, surgery is not recommended in patients over 18 months of age. However, for children younger than 18 months, surgery should be discussed with caregivers using a shared decision-making process.

Cognitive Outcomes of Children With Sagittal Craniosynostosis Treated With Either Endoscopic or Open Calvarial Vault Surgery.

Importance: Several studies have reported a higher incidence of neurodevelopmental delays and cognitive deficits in patients with single-suture craniosynostosis; however, there are few studies examining the associations of repair type with cognitive outcomes. Objective: To measure differences in neuropsychological outcomes between school-age children who were treated for sagittal craniosynostosis and unaffected controls and explore differences in cognitive function among children with sagittal craniosynostosis who were previously treated with either endoscopic strip craniectomy or open calvarial vault surgery. Design, Setting, and Participants: This cohort study was performed between 2018 and 2022. Eligible participants included patients aged 5 to 17 years who had previously been seen as infants or toddlers (<3 years) at 1 of 3 surgical centers for craniosynostosis repair with either endoscopic surgery or open calvarial vault surgery. A separate cohort of unaffected controls were included for comparison. Data analysis was conducted from November 2023 to February 2024. Exposures: Open calvarial vault surgery or endoscopic repair for single-suture craniosynostosis. Main Outcomes and Measures: The primary outcome was the Differential Ability Scales-II (DAS-II) General Conceptual Ability (GCA) score, an index for overall intellectual ability. Secondary outcomes included DAS-II subscale scores (Verbal Ability, Nonverbal Reasoning, Spatial Ability, Working Memory, and Processing Speed), and Patient-Reported Outcomes Measurement Information System (PROMIS) cognitive function scores. Results: A total of 81 patients with sagittal craniosynostosis (59 male [73%]; 22 female [27%]) and 141 controls (81 male [57%]; 60 female [43%]) were included. Of the 81 participants with sagittal craniosynostosis, 46 underwent endoscopic repair and 35 underwent open repair. Median (range) age at time of follow-up assessment was 7.7 (5.0-14.8) years for children with sagittal craniosynostosis and median age at assessment was 8.5 (7.7-10.5) years for controls. After controlling for age at assessment, sex, and socioeconomic status, there was no statistically significant or clinically meaningful difference in GCA scores between children who underwent endoscopic repair (adjusted mean score, 100; 95% CI, 96-104) and open repair (adjusted mean score, 103; 95% CI, 98-108) (P > .99). We found no significant difference in PROMIS scores between repair types (median [range] for endoscopic repair 54 [31-68] vs median [range] for open repair 50 [32-63]; P = .14). When comparing the treatment groups with the unaffected controls, differences in subscale scores for GCA and working memory were observed but were within normal range. Conclusions and Relevance: In this cohort study, there were no statistically or clinically significant differences in cognitive outcomes among school-age children by and type of surgical procedure used to repair nonsyndromic sagittal craniosynostosis. These findings suggest primary care clinicians should be educated about different options for craniosynostosis surgery to ensure early referral of these patients so that all treatment options remain viable.

MRI and pathology comparisons in Rasmussen's encephalitis: a multi-institutional examination of hemispherotomy outcomes relative to imaging and histological severity.

PURPOSE: Rasmussen encephalitis (RE) is a very rare chronic neurological disorder of unilateral inflammation of the cerebral cortex. Hemispherotomy provides the best chance at achieving seizure freedom in RE patients, but with significant risks and variable long-term outcomes. The goal of this study is to utilize our multicenter pediatric cohort to characterize if differences in pathology and/or imaging characterization of RE may provide a window into post-operative seizure outcomes, which in turn could guide decision-making for parents and healthcare providers. METHODS: This multi-institutional retrospective review of medical record, imaging, and pathology samples was approved by each individual institution's review board. Data was collected from all known pediatric cases of peri-insular functional hemispherotomy from the earliest available electronic medical records. Mean follow-up time was 4.9 years. Clinical outcomes were measured by last follow-up visit using both Engel and ILAE scoring systems. Relationships between categorical and continuous variables were analyzed with Pearson correlation values. RESULTS: Twenty-seven patients met study criteria. No statistically significant correlations existed between patient imaging and pathology data. Pathology stage, MRI brain imaging stages, and a combined assessment of pathology and imaging stages showed no statistically significant correlation to post-operative seizure freedom rates. Hemispherectomy Outcome Prediction Scale scoring demonstrated seizure freedom in only 71% of patients receiving a score of 1 and 36% of patients receiving a score of 2 which were substantially lower than predicted. CONCLUSIONS: Our analysis did not find evidence for either independent or combined analysis of imaging and pathology staging being predictive for post peri-insular hemispherotomy seizure outcomes, prompting the need for other biomarkers to be explored. Our data stands in contrast to the recently proposed Hemispherectomy Outcome Prediction Scale and does not externally validate this metric for an RE cohort.

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

OBJECTIVES: Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy. METHODS: Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/). RESULTS: The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE: Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.

Laser interstitial thermal therapy compared with open resection for treating subependymal giant cell astrocytoma.

OBJECTIVE: Subependymal giant cell astrocytomas (SEGAs) are WHO grade 1 tumors associated with tuberous sclerosis that classically arise from the ventricular wall near the caudate groove and foramen of Monro. Laser interstitial thermal therapy (LITT) is a minimally invasive surgical technique, which works by heating a stereotactically placed laser fiber to ablative temperatures under MRI thermometry monitoring. In this paper, the authors present LITT as a surgical alternative to open resection of SEGAs. METHODS: Twelve patients with SEGAs who underwent 16 procedures between 2007 and 2022 at a single institution were retrospectively reviewed. These patients underwent either open resection or LITT. Clinical data, imaging, recurrence rate, further treatments, and related complications were analyzed. RESULTS: Among the 16 procedures, 9 were open resection and 7 were LITT. An external ventricular drain was placed in 66% (6/9) of open procedures and 57.1% (4/7) of LITT cases. A septostomy was performed in 56% (5/9) of open procedures and 29% (2/7) of LITT cases. Complication rates were higher in open cases than in LITT procedures (44% vs 0%, p < 0.05). Complications included hydrocephalus, transient venous ischemia, wound infection, and bone flap migration. The median length of hospital stay was 4 days (IQR 3.3-5.5 days) for open cases and 4 days (IQR 3.0-7.0 days) for LITT procedures. Recurrence or progression occurred after 3 open cases and 2 LITT cases (33% vs 33%, p = 0.803). For the recurrences, 2 open cases underwent stereotactic radiosurgery, 1 open case underwent LITT, and 1 LITT case underwent repeat LITT. Among the LITT cases, only the patients with no decrease in tumor size by 6 months experienced tumor progression afterward. The 2 LITT cases with progression were the only ones with calcification present on preoperative imaging. The median follow-up times for cases assessed for progression were 8.4 years (IQR 3.8-14.4 years) for open resection and 3.9 years (IQR 3.4-5.1 years) for LITT. CONCLUSIONS: The small size of this case series limits generalizability or adequate comparison of safety. However, this series adds to the literature supporting LITT as a less invasive surgical alternative to open resection of SEGAs and demonstrates that LITT has similar recurrence and/or progression rates to open resection. Additional studies with more data are necessary for comprehensive comparisons between open resection and LITT for treating SEGA.

School-age anthropometric and patient-reported outcomes after open or endoscopic repair of sagittal craniosynostosis.

OBJECTIVE: Several studies have compared perioperative parameters and early postoperative morphology between endoscope-assisted strip craniectomy with orthotic therapy (endoscopic repair) and cranial vault remodeling (open repair). To extend these results, the authors evaluated school-age anthropometric outcomes after these techniques across three institutions. METHODS: School-aged children (age range 4-18 years) with previously corrected isolated sagittal craniosynostosis were enrolled. Upon inclusion, 3D photographs and patient-reported outcomes were obtained, and the cephalic index and head circumference z-scores were calculated. Analyses of covariance models controlling for baseline differences and a priori covariates were performed. RESULTS: Eighty-one participants (median [range] age 7 [4-15] years) were included. The mean (95% CI) school-age cephalic index was significantly higher in the endoscopic cohort, though within the normal range for both groups (endoscopic 78% [77%-79%] vs open 76% [74%-77%], p = 0.027). The mean change in the cephalic index from preoperation to school age was significantly greater in the endoscopic group (9% [7%-11%] vs open 3% [1%-5%], p < 0.001). Compared to preoperative measurements, mean school-age head circumference z-scores decreased significantly more in the open cohort (-1.6 [-2.2 to -1.0] vs endoscopic -0.3 [-0.8 to -0.2], p = 0.002). Patient-reported levels of stigma were within the normal limits for both groups. CONCLUSIONS: Endoscopic and open repair techniques effectively normalize school-age anthropometric outcomes. However, endoscopic repair produces a clinically meaningful and significantly greater improvement in the school-age cephalic index, with maintenance of head growth. These findings demonstrate the importance of early referral by pediatricians and inform treatment decisions.

Subependymal giant-cell astrocytomas in the absence of tuberous sclerosis.

OBJECTIVE: Tuberous sclerosis is a rare genetic condition caused by TSC1 or TSC2 mutations that can be inherited, sporadic, or the result of somatic mosaicism. Subependymal giant-cell astrocytoma (SEGA) is a major diagnostic feature of tuberous sclerosis complex (TSC). This study aimed to present a series of cases in which a pathological diagnosis of SEGA was not diagnostic of tuberous sclerosis. METHODS: The authors retrospectively reviewed a clinical case series of 5 children who presented with a SEGA tumor to Johns Hopkins All Children's Hospital and St. Louis Children's Hospital between 2010 and 2022 and whose initial genetic workup was negative for tuberous sclerosis. All patients were treated with craniotomy for SEGA resection. TSC genetic testing was performed on all SEGA specimens. RESULTS: The children underwent open frontal craniotomy for SEGA resection from the ages of 10 months to 14 years. All cases demonstrated the classic imaging features of SEGA. Four were centered at the foramen of Monro and 1 in the occipital horn. One patient presented with hydrocephalus, 1 with headaches, 1 with hand weakness, 1 with seizures, and 1 with tumor hemorrhage. Somatic TSC1 mutation was present in the SEGA tumors of 2 patients and TSC2 mutation in 1 patient. Germline TSC mutation testing was negative for all 5 cases. No patient had other systemic findings of tuberous sclerosis on ophthalmological, dermatological, neurological, renal, or cardiopulmonary assessments and thus did not meet the clinical criteria for tuberous sclerosis. The average follow-up was 6.7 years. Recurrence was noted in 2 cases, in which 1 patient underwent radiosurgery and 1 was started on a mammalian target of rapamycin (mTOR) inhibitor (rapamycin). CONCLUSIONS: There may be intracranial implications of somatic mosaicism associated with tuberous sclerosis. Children who are diagnosed with SEGA do not necessarily have a diagnosis of tuberous sclerosis. Tumors may carry a TSC1 or TSC2 mutation, but germline testing can be negative. These children should continue to be followed with serial cranial imaging for tumor progression, but they may not require the same long-term monitoring as patients who are diagnosed with germline TSC1 or TSC2 mutations.

Surgical outcomes of open and laser interstitial thermal therapy approaches for corpus callosotomy in pediatric epilepsy.

OBJECTIVE: Corpus callosotomy (CC) is a palliative surgical intervention for patients with medically refractory epilepsy that has evolved in recent years to include a less-invasive alternative with the use of laser interstitial thermal therapy (LITT). LITT works by heating a stereotactically placed laser fiber to ablative temperatures under real-time magnetic resonance imaging (MRI) thermometry. This study aims to (1) describe the surgical outcomes of CC in a large cohort of children with medically refractory epilepsy, (2) compare anterior and complete CC, and (3) review LITT as a surgical alternative to open craniotomy for CC. METHODS: This retrospective cohort study included 103 patients <21 years of age with at least 1 year follow-up at a single institution between 2003 and 2021. Surgical outcomes and the comparative effectiveness of anterior vs complete and open versus LITT surgical approaches were assessed. RESULTS: CC was the most common surgical disconnection (65%, n = 67) followed by anterior two-thirds (35%, n = 36), with a portion proceeding to posterior completion (28%, n = 10). The overall surgical complication rate was 6% (n = 6/103). Open craniotomy was the most common approach (87%, n = 90), with LITT used increasingly in recent years (13%, n = 13). Compared to open, LITT had shorter hospital stay (3 days [interquartile range (IQR) 2-5] vs 5 days [IQR 3-7]; p < .05). Modified Engel class I, II, III, and IV outcomes at last follow-up were 19.8% (n = 17/86), 19.8% (n = 17/86), 40.2% (n = 35/86), and 19.8% (n = 17/86). Of the 70 patients with preoperative drop seizures, 75% resolved postoperatively (n = 52/69). SIGNIFICANCE: No significant differences in seizure outcome between patients who underwent only anterior CC and complete CC were observed. LITT is a less-invasive surgical alternative to open craniotomy for CC, associated with similar seizure outcomes, lower blood loss, shorter hospital stays, and lower complication rates, but with longer operative times, when compared with the open craniotomy approach.

Multicenter comparison of head shape outcomes for three minimally invasive strip craniectomy techniques for sagittal craniosynostosis.

OBJECTIVE: A literature gap exists comparing whole head shape outcome following correction of sagittal craniosynostosis. The objective of this multicenter study was to provide an analysis of long-term results following three different endoscopic strip craniectomy techniques for correction of sagittal craniosynostosis: 1) spring-assisted strip craniectomy, 2) wide-strip craniectomy with biparietal and bitemporal barrel-stave wedge osteotomies plus helmet orthosis, and 3) narrow-strip craniectomy plus orthosis without barrel staves. METHODS: Pre- and postoperative 3D stereophotogrammetric images were collected from patients who underwent craniosynostosis surgery. Procedures were divided among institutions as follows: spring-assisted strip craniectomies were performed at Atrium Health Wake Forest Baptist Hospital; narrow-strip craniectomies were performed at St. Louis Children's Hospital by one craniofacial surgeon; and wide-vertex craniectomies were performed at St. Louis Children's Hospital prior to 2010, and then continued at Children's Medical Center Dallas. Pre- and postoperative 3D whole-head composite images were generated for each procedure to visually represent outcomes at final follow-up and compared with age-matched normal controls. RESULTS: Patients in the spring-assisted strip craniectomy group showed normalization of frontal bossing and skull height compared with age-matched controls, whereas patients undergoing wide-strip craniectomy showed greater correction of occipital protrusion. Patients in the narrow-strip craniectomy cohort had intermediate results between these outcomes. Nested aggregate head shapes showed good correction of head shapes from all techniques. CONCLUSIONS: This large, retrospective, multicenter study illustrated whole head shape outcomes from three different craniectomy procedures. Although each procedure showed some differences in loci of primary correction, all three surgical methods demonstrated good correction of primary scaphocephalic deformity.

Endoscopic Placement of Intracystic Catheters: A Technical Note.

BACKGROUND: Intraventricular neuroendoscopic surgery for tumor resection, biopsy, or cyst fenestration frequently requires precise placement of an intraventricular or intracystic catheter. Placement under direct visualization is not feasible because of small bore of working channel of the standard small ventriculoscope. Various techniques have been reported using a separate transcortical trajectory, endoluminal endoscope, or endovascular guide wire. OBJECTIVE: To describe a technique allowing precise placement of intraventricular/intracystic catheter using a small bore working ventriculoscope, without need for additional equipment. METHODS: Description of the technique including intraoperative photographs, video, and illustrative cases are provided. RESULTS: The peel-away sheath is peeled off approximately 1 to 2 cm to allow for the shaft of the endoscope to pass past its tip. Ventricular access is gained using the peel-away sheath. After the stylet is removed, the peel-away sheath is not peeled further or stapled to the skin. The endoscope is introduced into the ventricle through the peel-away sheath. After the required intraventricular work is performed, the endoscope is maneuvered into the location of the desired catheter position. The peel-away sheath is slowly advanced over the stationary endoscope past its tip. While the peel-away sheath is being held in place, the endoscope is removed. After the catheter has been introduced into the peel-away sheath to a premeasured depth, the peel-away sheath is peeled and removed. The catheter is then connected to collection system, reservoir or shunt system. CONCLUSION: The current technique allows for the precise placement of intraventricular/intracystic catheters without the need for additional equipment or a separate transcortical trajectory.

"Calvarial Vault Remodeling Technique for Lambdoid Craniosynostosis."

SUMMARY: Premature fusion of the lambdoid suture is the most uncommon single suture synostosis. It presents with a classic "windswept" appearance, with a trapezoid-shaped head and significant skull asymmetry notable for an ipsilateral mastoid bulge and contralateral frontal bossing. Due to the rarity of lambdoid synostosis, little is known about optimal techniques for its treatment. In particular, the proximity of the lambdoid suture to critical intracranial structures such as the superior sagittal and transverse sinuses represents a potential for significant intraoperative bleeding. Prior work has shown that parietal asymmetry persists after repair in these cases. Here, we present a technique for the treatment of unilateral lambdoid craniosynostosis along with two representative cases.This calvarial vault remodeling technique requires the removal of both ipsilateral and contralateral parietal bones. These are moved across hemispheres and re-inset on opposite sides to help correct the parietal asymmetry. Obliquely orientated barrel stave osteotomies are performed to provide a safe mechanism for correction of occipital flattening. Our early results show improvement in correction of volume asymmetry one year post-operatively relative to patients treated with prior calvarial vault remodeling techniques. We believe the technique presented here corrects the windswept appearance in patients with lambdoid craniosynostosis while also reducing the potential for complications. Further work will be necessary to confirm this technique's long-term efficacy in a larger cohort.

Selective Dorsal Rhizotomy For Treatment of Spasticity After Hemispherectomy In Children: A Case Report.

Performing a hemispherotomy or hemispherectomy is known to treat medically intractable epilepsy successfully, yet contralateral hemiparesis and increased muscle tone follow the epilepsy surgery. Spasticity and coexisting dystonia presumably cause the increased muscle tone in the lower extremity on the opposite side of epilepsy surgery. However, the extent of the role of spasticity and dystonia in high muscle tone is unknown. A selective dorsal rhizotomy is performed to reduce spasticity. If a selective dorsal rhizotomy is performed in the affected patient and muscle tone is reduced, the high muscle tone is not due to dystonia. Two children, who previously underwent a hemispherectomy or hemispherotomy, had a selective dorsal rhizotomy (SDR) performed in our clinic. Both children underwent orthopedic surgery to treat heel cord contractures. To study the extent of the role of spasticity and dystonia in high muscle tone, the mobility of the two children was examined pre- and post-SDR. The children had follow-ups 12 months and 56 months after SDR to study long-term effects. Before SDR, both children showed signs of spasticity. The SDR procedure removed spasticity, and muscle tone in the lower extremity became normal. Importantly, dystonia did not surface after SDR. Patients started independent walking less than two weeks after SDR. Sitting, standing, walking, and balance improved. They could walk longer distances while experiencing less fatigue. Running, jumping, and other more vigorous physical activities became possible. Notably, one child showed voluntary foot dorsiflexion that was absent before SDR. The other child showed improvement in voluntary foot dorsiflexion that was present before SDR. Both children maintained the progress at the 12 and 56-month follow-up visits. The SDR procedure normalized muscle tone and improved ambulation by removing spasticity. The high muscle tone following the epilepsy surgery was not due to dystonia.

Magnetic resonance imaging-guided stereotactic laser ablation therapy for the treatment of pediatric epilepsy: a retrospective multiinstitutional study.

OBJECTIVE: The authors of this study evaluated the safety and efficacy of stereotactic laser ablation (SLA) for the treatment of drug-resistant epilepsy (DRE) in children. METHODS: Seventeen North American centers were enrolled in the study. Data for pediatric patients with DRE who had been treated with SLA between 2008 and 2018 were retrospectively reviewed. RESULTS: A total of 225 patients, mean age 12.8 ± 5.8 years, were identified. Target-of-interest (TOI) locations included extratemporal (44.4%), temporal neocortical (8.4%), mesiotemporal (23.1%), hypothalamic (14.2%), and callosal (9.8%). Visualase and NeuroBlate SLA systems were used in 199 and 26 cases, respectively. Procedure goals included ablation (149 cases), disconnection (63), or both (13). The mean follow-up was 27 ± 20.4 months. Improvement in targeted seizure type (TST) was seen in 179 (84.0%) patients. Engel classification was reported for 167 (74.2%) patients; excluding the palliative cases, 74 (49.7%), 35 (23.5%), 10 (6.7%), and 30 (20.1%) patients had Engel class I, II, III, and IV outcomes, respectively. For patients with a follow-up ≥ 12 months, 25 (51.0%), 18 (36.7%), 3 (6.1%), and 3 (6.1%) had Engel class I, II, III, and IV outcomes, respectively. Patients with a history of pre-SLA surgery related to the TOI, a pathology of malformation of cortical development, and 2+ trajectories per TOI were more likely to experience no improvement in seizure frequency and/or to have an unfavorable outcome. A greater number of smaller thermal lesions was associated with greater improvement in TST. Thirty (13.3%) patients experienced 51 short-term complications including malpositioned catheter (3 cases), intracranial hemorrhage (2), transient neurological deficit (19), permanent neurological deficit (3), symptomatic perilesional edema (6), hydrocephalus (1), CSF leakage (1), wound infection (2), unplanned ICU stay (5), and unplanned 30-day readmission (9). The relative incidence of complications was higher in the hypothalamic target location. Target volume, number of laser trajectories, number or size of thermal lesions, or use of perioperative steroids did not have a significant effect on short-term complications. CONCLUSIONS: SLA appears to be an effective and well-tolerated treatment option for children with DRE. Large-volume prospective studies are needed to better understand the indications for treatment and demonstrate the long-term efficacy of SLA in this population.

Outcomes after Endoscope-Assisted Strip Craniectomy and Orthotic Therapy for Syndromic Craniosynostosis.

BACKGROUND: Endoscopic craniosynostosis repair has emerged as an effective alternative to open repair, but data are limited on treatment of the 15% to 24% of patients with syndromic diagnoses. In this study, the authors examine postoperative outcomes after endoscopic repair in syndromic craniosynostosis. METHODS: Retrospective review was performed of all consecutive patients undergoing endoscopic repair and all syndromic patients undergoing open repair from 2006 to 2021. Demographics, complications, and reoperations were compared between groups. Patient-reported measures of stigma and cognitive function were recorded at age 5 years and older. RESULTS: A total of 335 patients underwent endoscopic repair, of which 38 (11%) had syndromic craniosynostosis. Syndromic craniosynostosis was associated with bicoronal involvement ( P < 0.001) and female sex ( P = 0.003). Secondary procedures were significantly more common in the syndromic group (24% versus 2.4%; P < 0.001), as were transfusions (18% versus 6.4%; P = 0.018). Secondary procedures were performed at a mean 2.8 years of age (range, 10 months to 8 years), and most commonly consisted of fronto-orbital advancement (seven in the syndromic group, and three in the nonsyndromic group). The degree of patient-reported stigma was higher in patients with syndromes ( P = 0.002), but cognitive function did not differ significantly ( P = 0.065). The incidence of reoperations after open repair was 13%, but baseline differences precluded direct comparison with the endoscopic group. CONCLUSIONS: Minimally invasive approaches in early infancy can alleviate the need for additional cranial procedures in the growing child. Syndromic craniosynostoses are a complex and heterogeneous group, and in more severe cases, endoscopic repair can be considered an adjunct technique to reduce the number of major craniofacial procedures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Comprehensive multi-omic profiling of somatic mutations in malformations of cortical development.

Malformations of cortical development (MCD) are neurological conditions involving focal disruptions of cortical architecture and cellular organization that arise during embryogenesis, largely from somatic mosaic mutations, and cause intractable epilepsy. Identifying the genetic causes of MCD has been a challenge, as mutations remain at low allelic fractions in brain tissue resected to treat condition-related epilepsy. Here we report a genetic landscape from 283 brain resections, identifying 69 mutated genes through intensive profiling of somatic mutations, combining whole-exome and targeted-amplicon sequencing with functional validation including in utero electroporation of mice and single-nucleus RNA sequencing. Genotype-phenotype correlation analysis elucidated specific MCD gene sets associated with distinct pathophysiological and clinical phenotypes. The unique single-cell level spatiotemporal expression patterns of mutated genes in control and patient brains indicate critical roles in excitatory neurogenic pools during brain development and in promoting neuronal hyperexcitability after birth.

Design and Validation of a 3D Printed Cranio-Facial Simulator: A Novel Tool for Surgical Education.

OBJECTIVE: To assess the ability of current 3D printing technology to generate a craniofacial bony and soft tissue anatomical model for use in simulating the performance of a fronto-orbital advancement (FOA) osteotomy and then to further assess the value of the model as an educational tool. DESIGN: Anatomic models were designed with a process of serial anatomic segmentation/design, 3D printing, dissection, and device refinement. A validation study was conducted with 5 junior and 5 senior plastic surgery residents. The validation study incorporated a multiple-choice Knowledge Assessment test (KA), an Objective Structured Assessment of Technical skills (OSATs), a Global Rating Scale (GRS) and a Michigan Standard Simulation Experience Scale (MiSSES). We compared the scores of both the junior and senior residents and compared junior resident scores, before and after viewing a lecture/demonstration. RESULTS: MiSSES showed high face validity with a score of 85.1/90, signifying high satisfaction with the simulator learning experience. Simulation and the lecture/demonstration improved the junior resident average KA score from 5.6/10 to 9.6/10 (P = .02), OSATs score from 32.4/66 to 64.4/66 (P < .001) and GRS score from 13.9/35 to 27.5/35 (P < .001). The senior residents OSATs score of 56.3/66 was higher than the pre-lecture juniors (32.4/66) (P < .001), but lower than the post-lecture juniors (64.4/66) (P < .001). CONCLUSION: We have successfully fabricated a 3D printed craniofacial simulator capable of being used as an educational tool alongside traditional surgical training. Next steps would be improving soft tissue realism, inclusion of patient and disease specific anatomy and creation of models for other surgical specialties.

Cost-effectiveness of invasive monitoring strategies in epilepsy surgery.

OBJECTIVE: Drug-resistant epilepsy occurs in up to 40% of patients with epilepsy who may be considered for epilepsy surgery. For drug-resistant focal epilepsy, up to 50% of patients require invasive monitoring prior to surgery. Of the most common invasive monitoring strategies (subdural electrodes [SDEs] and stereo-electroencephalography [sEEG]), the most cost-effective strategy is unknown despite substantial differences in morbidity profiles. METHODS: Using data collected from an internationally representative sample published in available systematic reviews and meta-analyses, this economic evaluation study employs a decision analysis model to simulate the risks and benefits of SDE and sEEG invasive monitoring strategies. In this model, patients faced differing risks of morbidity, mortality, resection, and seizure freedom depending on which invasive monitoring strategy they underwent. A range of cost values was obtained from a recently published single-center cost-utility analysis. The model considers a base case simulation of a characteristic patient with drug-resistant epilepsy using clinical parameters obtained from systematic reviews of invasive monitoring available in the literature. The main outcome measure was the probability of a positive outcome after invasive monitoring, which was defined as improvement in seizures without a complication. Cost-effectiveness was measured using an incremental cost-effectiveness ratio (ICER). RESULTS: Invasive monitoring with sEEG had an increased cost of $274 and increased probability of effectiveness of 0.02 compared with SDEs, yielding an ICER of $12,630 per positive outcome obtained. Sensitivity analyses varied parameters widely and revealed consistent model results across the range of clinical parameters reported in the literature. One-way sensitivity analyses revealed that invasive monitoring strategy costs were the most influential parameter for model outcome. CONCLUSIONS: In this analysis, based on available observational data and estimates of complication costs, invasive monitoring with either SDEs or sEEG was nearly equivalent in terms of cost-effectiveness.

Impact of age at endoscopic metopic synostosis repair on anthropometric outcomes.

OBJECTIVE: Endoscopic strip craniectomy for metopic craniosynostosis relies on rapid growth and postoperative helmeting for correction. Endoscopic repair is generally performed before patients reach 4 months of age, and outcomes in older patients have yet to be quantified. Here, the authors examined a cohort of patients treated with endoscopic repair before or after 4 months of age to determine aesthetic outcomes of delayed repairs. METHODS: Data from eligible patients were retrospectively assessed and aggregated in a dedicated metopic synostosis database. Inclusion criteria were radiographically confirmed metopic synostosis and endoscopic treatment. Patients were dichotomized into two groups: those younger than 4 months and those 4 months or older at the time of repair. The frontal width and interfrontal divergence angle (IFDA) were measured on reconstructed CT images. These measurements, alongside operative time, estimated blood loss, and transfusion rates, were compared between groups using the Student t-test or chi-square test. RESULTS: The study population comprised 28 patients treated before 4 months of age and 8 patients treated at 4-6 months of age. Patient sex and perioperative complications did not differ by age group. Older age at repair was not significantly associated with 1-year postoperative IFDA (140° ± 4.2° vs 142° ± 5.0°, p = 0.28) or frontal width (84 ± 5.2 vs 83 ± 4.4 mm, p = 0.47). CONCLUSIONS: One-year postoperative IFDA and frontal width do not differ significantly between patients treated before and after 4 months of age. Further study with longer follow-up is necessary to confirm the longevity of these results at skeletal maturity.

Survival After Resection of Newly-Diagnosed Intracranial Grade II Ependymomas: An Initial Multicenter Analysis and the Logistics of Intraoperative Magnetic Resonance Imaging.

OBJECTIVE: To identify factors, including the use of intraoperative magnetic resonance imaging (iMRI), impacting overall survival (OS) and progression-free survival (PFS) after resections of newly diagnosed intracranial grade II ependymomas performed across 4 different institutions. METHODS: Analyses of a multicenter mixed retrospective/prospective database assessed the impact of patient, treatment, and tumor characteristics on OS and PFS. iMRI workflow and logistics were also outlined. RESULTS: Forty-three patients were identified (mean age 25.4 years, mean follow-up 52.8 months). The mean OS was 52.8 ± 44.7 months. Univariate analyses failed to identify prognostic factors associated with OS, likely due to relatively shorter follow-up time for this less aggressive glioma subtype. The mean PFS was 43.7 ± 39.8 months. Multivariate analyses demonstrated that gross-total resection was associated with prolonged PFS compared to both subtotal resection (STR) (P = 0.005) and near-total resection (P = 0.01). Infratentorial location was associated with improved PFS compared to supratentorial location (P = 0.04). Log-rank analyses of Kaplan-Meier survival curves showed that increasing extent of resection (EOR) led to improved OS specifically for supratentorial tumors (P = 0.02) and improved PFS for all tumors (P < 0.001). Thirty cases (69.8%) utilized iMRI, of which 12 (27.9%) involved additional resection after iMRI. Of these, 8/12 (66.7%) resulted in gross-total resection, while 2/12 (16.7%) were near-total resection and 2/12 (16.7%) were subtotal resection. iMRI was not an independent prognosticator of PFS (P = 0.72). CONCLUSIONS: Greater EOR and infratentorial location were associated with increased PFS for grade II ependymomas. Greater EOR was associated with longer OS only for supratentorial tumors. A longer follow-up is needed to establish prognostic factors for this cohort, including use of iMRI.

A multi-institutional survey on calvarial vault remodeling techniques for sagittal synostosis and outcomes analysis for patients treated at 12 months and older.

OBJECTIVE: Surgical treatment of sagittal craniosynostosis is challenging in older patients. This study aimed to assess the effect of increasing age on open surgical technique selection and patient outcomes using the multi-institutional Synostosis Research Group (SynRG) collaboration. METHODS: Surgeons in SynRG were surveyed for key influences on their preferred open calvarial vault remodeling techniques at various patient ages: < 6, 6-12, and > 12 months. The SynRG database was then queried for open repairs of nonsyndromic sagittal craniosynostosis performed for patients older than 12 months of age. Perioperative measures, complications, and preoperative and postoperative cephalic indices were reviewed. RESULTS: All surgeons preferred to treat patients at an earlier age, and most (89%) believed that less-optimal outcomes were achieved at ages older than 12 months. The modified pi procedure was the dominant technique in those younger than 12 months, while more involved open surgical techniques were performed for older patients, with a wide variety of open calvarial vault remodeling techniques used. Forty-four patients met inclusion criteria, with a mean (± SD) age at surgery of 29 ± 16 months. Eleven patients underwent parietal reshaping, 10 parietal-occipital switch, 9 clamshell craniotomy, 7 geometric parietal expansion, 6 modified pi procedure, and 1 parietal distraction. There were no readmissions, complications, or mortality within 30 days postoperatively. Patients' cephalic indices improved a mean of 6.4% ± 4.0%, with a mean postoperative cephalic index of 74.2% ± 4.9%. Differences in postoperative cephalic index (p < 0.04) and hospital length of stay (p = 0.01) were significant between technique cohorts. Post hoc Tukey-Kramer analysis identified the parietal reshaping technique as being significantly associated with a reduced hospital length of stay. CONCLUSIONS: Patient age is an important driver in technique selection, with surgeons selecting a more involved calvarial vault remodeling technique in older children. A variety of surgical techniques were analyzed, with the parietal reshaping technique being significantly associated with reduced length of stay; however, multiple perioperative factors may be contributory and require further analysis. When performed at high-volume centers by experienced pediatric neurosurgeons and craniofacial surgeons, open calvarial vault techniques can be a safe method for treating sagittal craniosynostosis in older children.