Preoperative Frontal and Parietal Bone Thickness Assessment to Predict Blood Loss and Transfusion During Extended Suturectomy for Isolated Sagittal Craniosynostosis.

OBJECTIVE: To predict the morbidity of sagittal suturectomy using preoperative computer tomographic measurement of frontal and parietal bone thickness in osteotomy sites. DESIGN: Retrospective analysis. SETTING: Tertiary children's hospital. PATIENTS: Fifty infants with nonsyndromic, isolated sagittal craniosynostosis who underwent extended sagittal suturectomy from 2015-2022. METHODS: Mean thickness of the frontal and parietal bone in regions of osteotomies were determined for each patient from preoperative CT images obtained within 30 days prior to suturectomy. The relationship between bone thickness (mm) and estimated blood loss (mL) was evaluated using Spearman's correlation and a multivariable model that adjusted for patient weight and surgery duration. The association between bone thickness and perioperative blood transfusion was evaluated using a multivariable logistic model controlling for patient weight and surgery duration. MAIN OUTCOME MEASURES: Estimated blood loss, perioperative blood transfusion. RESULTS: Frontal and parietal bone thickness in the region of osteotomies were positively correlated with estimated blood loss (p < 0.01). After adjusting for patient weight and duration of operation, both parietal and frontal bone thickness were associated with intraoperative blood loss (R2 = 0.292, p = 0.002 and R2 = 0.216, p = 0.026). Thicker frontal and parietal bone in the line of osteotomies resulted in significantly higher odds of blood transfusion. Bone thickness in the line of parietal osteotomies was 76% accurate at identifying patients who would require blood transfusion (p = 0.004). CONCLUSIONS: Frontal and parietal bone thickness in the line of osteotomies is associated with blood loss and perioperative blood transfusion for sagittal suturectomy operations.

Meningomyelocele Reconstruction: Comparison of Repair Methods via Systematic Review.

PURPOSE: The purpose of this article was to appraise the various methods of reconstruction for meningomyelocele (MMC) defects. METHODS: A systematic review of the literature was performed to evaluate all reconstructions for MMC. The method of reconstruction was categorized by: primary closure with and without fascial flaps, random pattern flaps, VY advancement flaps (VY), perforator flaps, and myocutaneous flaps. Perforator flaps were subsequently subcategorized based on the type of flap. RESULTS: Upon systematic review, 567 articles were screened with 104 articles assessed for eligibility. Twenty-nine articles were further reviewed and included for qualitative synthesis. Two hundred seventy patients underwent MMC repair. The lowest rates of major wound complications (MWC) were associated with myocutaneous and random pattern flaps. A majority of MWC was in the lumbrosacral/sacral region (87.5% of MWC). In this region, random patterns and perforator flaps demonstrated the lowest rate of MWC (4.5, 8.1%). CONCLUSIONS: Plastic surgery consultation should be strongly considered for MMC with defects in the lumbosacral/sacral region. Perforator flaps are excellent options for the reconstruction of these defects.

Long term outcome after surgical treatment for hypothalamic hamartoma.

PURPOSE: To determine long-term outcome for seizure control and clinical predictors for seizure freedom in patients undergoing surgical treatment for epilepsy associated with hypothalamic hamartoma (HH). METHODS: 155 patients underwent surgical treatment for HHs and treatment-resistant epilepsy at one center (Barrow Neurological Institute at St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA) between February 2003 and June 2010. Data collection included medical record review and direct follow-up interviews to determine seizure outcome. Statistical analysis included descriptive summaries of patient characteristics and time-to-event analysis for seizure freedom. RESULTS: Long-term survival with follow-up of at least five years since first surgical treatment was available for 108 patients (69.7% of the treatment cohort). The surgical approach for first HH intervention consisted of transventricular endoscopic resection (n = 57; 52.8%), transcallosal interforniceal resection (n = 35; 32.4%), pterional resection (n = 7; 6.5%), and gamma knife radiosurgery (n = 9; 8.3%). Multiple surgical procedures were required for 39 patients (36.1%). There were 10 known deaths from all causes in the treatment cohort (6.5%). Of these, one (0.6%) was related to immediate complications of HH surgery, three (1.9%) were attributed to Sudden Unexpected Death in Epileptic Persons (SUDEP), and one (0.6%) to complications of status epilepticus. For surviving patients with long-term follow-up, 55 (50.9%) were seizure-free for all seizure types. Univariable analysis showed that seizure-freedom was related to 1) absence of a pre-operative history for central precocious puberty (p = 0.01), and 2) higher percentage of HH lesion disconnection after surgery (p = 0.047). Kaplan-Meier survival analysis shows that long-term seizure outcome following HH surgery is comparable to short-term results. SUMMARY: These uncontrolled observational results show that long-term seizure control following HH surgical treatment is comparable to other forms of epilepsy surgery. Late relapse (at least one year after surgery) and SUDEP do occur, but in a relatively small number of treated patients. These results inform clinical practice and serve as a comparable benchmark for newer technologies for HH surgery, such as magnetic resonance imaging-guided laser interstitial thermal therapy, where long-term outcome results are not yet available.

Hydrocephalus surveillance following CSF diversion: a modified Delphi study.

OBJECTIVE: Long-term follow-up is often recommended for patients with hydrocephalus, but the frequency of clinical follow-up, timing and modality of imaging, and duration of surveillance have not been clearly defined. Here, the authors used the modified Delphi method to identify areas of consensus regarding the modality, frequency, and duration of hydrocephalus surveillance following surgical treatment. METHODS: Pediatric neurosurgeons serving as institutional liaisons to the Hydrocephalus Clinical Research Network (HCRN), or its implementation/quality improvement arm (HCRNq), were invited to participate in this modified Delphi study. Thirty-seven consensus statements were generated and distributed via an anonymous electronic survey, with responses structured as a 4-point Likert scale (strongly agree, agree, disagree, strongly disagree). A subsequent, virtual meeting offered the opportunity for open discussion and modification of the statements in an effort to reach consensus (defined as ≥ 80% agreement or disagreement). RESULTS: Nineteen pediatric neurosurgeons participated in the first round, after which 15 statements reached consensus. During the second round, 14 participants met virtually for review and discussion. Some statements were modified and 2 statements were combined, resulting in a total of 36 statements. At the conclusion of the session, consensus was achieved for 17 statements regarding the following: 1) the role of standardization; 2) preferred imaging modalities; 3) postoperative follow-up after shunt surgery (subdivided into immediate postoperative imaging, delayed postoperative imaging, routine clinical surveillance, and routine radiological surveillance); and 4) postoperative follow-up after an endoscopic third ventriculostomy. Consensus could not be achieved for 19 statements. CONCLUSIONS: Using the modified Delphi method, 17 consensus statements were developed with respect to both clinical and radiological follow-up after a shunt or endoscopic third ventriculostomy. The frequency, modality, and duration of surveillance were addressed, highlighting areas in which no clear data exist to guide clinical practice. Although further studies are needed to evaluate the clinical utility and cost-effectiveness of hydrocephalus surveillance, the current study provides a framework to guide future efforts to develop standardized clinical protocols for the postoperative surveillance of patients with hydrocephalus. Ultimately, the standardization of hydrocephalus surveillance has the potential to improve patient care as well as optimize the use of healthcare resources.

Hydrogel Check-Valves for the Treatment of Hydrocephalic Fluid Retention with Wireless Fully-Passive Sensor for the Intracranial Pressure Measurement.

Hydrocephalus (HCP) is a neurological disease resulting from the disruption of the cerebrospinal fluid (CSF) drainage mechanism in the brain. Reliable draining of CSF is necessary to treat hydrocephalus. The current standard of care is an implantable shunt system. However, shunts have a high failure rate caused by mechanical malfunctions, obstructions, infection, blockage, breakage, and over or under drainage. Such shunt failures can be difficult to diagnose due to nonspecific systems and the lack of long-term implantable pressure sensors. Herein, we present the evaluation of a fully realized and passive implantable valve made of hydrogel to restore CSF draining operations within the cranium. The valves are designed to achieve a non-zero cracking pressure and no reverse flow leakage by using hydrogel swelling. The valves were evaluated in a realistic fluidic environment with ex vivo CSF and brain tissue. They display a successful operation across a range of conditions, with negligible reverse flow leakage. Additionally, a novel wireless pressure sensor was incorporated alongside the valve for in situ intracranial pressure measurement. The wireless pressure sensor successfully replicated standard measurements. Those evaluations show the reproducibility of the valve and sensor functions and support the system's potential as a chronic implant to replace standard shunt systems.

Accessory Cranial Suture Leading to Abnormal Head Shape.

ABSTRACT: Accessory cranial sutures have been described in the literature and are most commonly associated with the parietal bone. These sutures are typically identified incidentally and there have been no reported cases of accessory cranial sutures leading to abnormal head shape.The authors present the case of a 3-month-old patient with multiple congenital anomalies and an accessory parietal suture leading to abnormal head shape. The patient was successfully treated with cranial orthotic therapy. To our knowledge, this is the first reported case of an accessory cranial suture leading to abnormal head shape.

Pediatric intracranial arterial injuries by penetrating gunshot wounds: an institutional experience.

PURPOSE: Pediatric intracranial injuries due to penetrating gunshot wounds are a rare entity that is often fatal. A subset of patients may experience an intracerebral arterial injury; however, literature on the pediatric population is limited. This study analyzes a large institution's experience with pediatric head gunshot wounds and intracranial arterial injuries. METHODS: All pediatric patients ≤ 18 years of age who presented to our institution with a penetrating gunshot wound from 2008 to 2018 were retrospectively analyzed. RESULTS: Thirty-seven patients presented with an intracerebral penetrating gunshot injury. There were 18 deaths (49%) in the cohort. A total of 20 patients (54%) had vascular imaging. Of the remaining 17 patients with no vascular imaging, 13 (35%) died before any vascular studies were obtained. Four (20%) of the 20 patients with vascular imaging experienced an intracerebral arterial injury. Three of these 4 patients died before treatment could be administered. One patient with a firearm injury underwent embolization of a distal middle cerebral artery pseudoaneurysm and was discharged home with a Glasgow Outcome Scale score of 5 on follow-up. CONCLUSION: Pediatric patients with penetrating intracranial gunshot wounds often die before vascular imaging can be obtained.

Three-Dimensionally Printed Microelectromechanical-System Hydrogel Valve for Communicating Hydrocephalus.

Hydrocephalus (HCP) is a chronic neurological brain disorder caused by a malfunction of the cerebrospinal fluid (CSF) drainage mechanism in the brain. The current standard method to treat HCP is a shunt system. Unfortunately, the shunt system suffers from complications including mechanical malfunctions, obstructions, infections, blockage, breakage, overdrainage, and/or underdrainage. Some of these complications may be attributed to the shunts' physically large and lengthy course making them susceptible to external forces, siphoning effects, and risks of infection. Additionally, intracranial catheters artificially traverse the brain and drain the ventricle rather than the subarachnoid space. We report a 3D-printed microelectromechanical system-based implantable valve to improve HCP treatment. This device provides an alternative approach targeting restoration of near-natural CSF dynamics by artificial arachnoid granulations (AGs), natural components for CSF drainage in the brain. The valve, made of hydrogel, aims to regulate the CSF flow between the subarachnoid space and the superior sagittal sinus, in essence, substituting for the obstructed arachnoid granulations. The valve, operating in a fully passive manner, utilizes the hydrogel swelling feature to create nonzero cracking pressure, PT ≈ 47.4 ± 6.8 mmH2O, as well as minimize reverse flow leakage, QO ≈ 0.7 µL/min on benchtop experiments. The additional measurements performed in realistic experimental setups using a fixed sheep brain also deliver comparable results, PT ≈ 113.0 ± 9.8 mmH2O and QO ≈ 3.7 µL/min. In automated loop functional tests, the valve maintains functionality for a maximum of 1536 cycles with the PT variance of 44.5 mmH2O < PT < 61.1 mmH2O and negligible average reverse flow leakage rates of ∼0.3 µL/min.

De Novo Variants Disrupting the HX Repeat Motif of ATN1 Cause a Recognizable Non-Progressive Neurocognitive Syndrome.

Polyglutamine expansions in the transcriptional co-repressor Atrophin-1, encoded by ATN1, cause the neurodegenerative condition dentatorubral-pallidoluysian atrophy (DRPLA) via a proposed novel toxic gain of function. We present detailed phenotypic information on eight unrelated individuals who have de novo missense and insertion variants within a conserved 16-amino-acid "HX repeat" motif of ATN1. Each of the affected individuals has severe cognitive impairment and hypotonia, a recognizable facial gestalt, and variable congenital anomalies. However, they lack the progressive symptoms typical of DRPLA neurodegeneration. To distinguish this subset of affected individuals from the DRPLA diagnosis, we suggest using the term CHEDDA (congenital hypotonia, epilepsy, developmental delay, digit abnormalities) to classify the condition. CHEDDA-related variants alter the particular structural features of the HX repeat motif, suggesting that CHEDDA results from perturbation of the structural and functional integrity of the HX repeat. We found several non-homologous human genes containing similar motifs of eight to 10 HX repeat sequences, including RERE, where disruptive variants in this motif have also been linked to a separate condition that causes neurocognitive and congenital anomalies. These findings suggest that perturbation of the HX motif might explain other Mendelian human conditions.

Magnetic Resonance Imaging-Guided Laser Interstitial Thermal Therapy for the Treatment of Hypothalamic Hamartomas: A Retrospective Review.

BACKGROUND: Hypothalamic hamartomas (HH) are rare lesions associated with treatment-resistant epilepsy. Open surgery results in modest seizure control (about 50%) but has a significant associated morbidity. Radiosurgery is limited to a subset of patients due to latent therapeutic effects. Magnetic resonance imaging-guided laser interstitial thermal therapy (LITT) offers a novel minimally invasive option. OBJECTIVE: To evaluate a single center's outcomes for the LITT treatment of HH. METHODS: We retrospectively reviewed our experience with LITT for the treatment of HH using our institution's prospectively maintained patient database. RESULTS: Eighteen patients (mean age, 21.1 yr; median age, 11 yr) underwent 21 total LITT treatments for HH. Mean follow-up was 17.4 mo. The length of stay was 1 night for 16 (89%) patients. At the end of follow-up, 11 of 18 patients (61%) had full disconnection of the HH, and 12 of 15 (80%) patients with gelastic seizures and 5 (56%) of 9 patients with nongelastic seizures were seizure free (International League Against Epilepsy Class 1). Immediate complications included a 39% (7/18) incidence of neurological deficits, including 1 case of hemiparesis. At the end of follow-up, 22% of patients (4/18) had persistent deficits. The hypothyroidism that occurred was delayed in 11% of patients (2/18), as was short-term memory loss (22%, 4/18) and weight gain (22%, 4/18). CONCLUSION: LITT therapy for HH can achieve excellent rates of seizure control with low morbidity and a short postoperative stay in a majority of patients. Additional research is needed to assess the durability of results and the full spectrum of cognitive outcomes.

Outcomes of Titanium Mesh Cranioplasty in Pediatric Patients.

PURPOSE: Cranial defects in children have been repaired with various materials ranging from autologous bone to synthetic materials. There is little published literature on the outcomes of titanium mesh cranioplasty (TMC) in calvarial reconstruction in the pediatric population. This study evaluates a pediatric cohort who underwent calvarial defect reconstruction with titanium mesh and assesses the efficacy and outcomes of TMC. METHODS: An Institutional Review Board approved retrospective review of patients ≤18 years of age who underwent cranioplasty from 1999 to 2014 at 2 centers was performed. The cohort undergoing TMC was studied. RESULTS: A total of 159 cranioplasties were performed. Autologous reconstruction included 84 bone flap replacements and 36 split calvarial bone graft reconstructions. Six patients underwent PEEK implant reconstruction. Titanium mesh cranioplasty was performed on 33 patients. Two patients underwent 2 separate cranioplasties. The median age of patients was 6 years (19 months to 18 years). The most common underlying etiologies were congenital syndromes/craniosynostosis (13 patients), and trauma (11). The majority of patients had prior cranial surgeries (85%). Various types of titanium mesh were used with sizes ranging from 2×3 cm to 19×20 cm, with some patients requiring distinct areas of defect reconstruction. Perioperative complications were noted in 2 patients that subsequently improved. Two patients had late soft tissue problems with complications of wound infections requiring resection of a portion of the mesh. Patients were followed an average of 4 years (range 13 days to 6.8 years), with 2 patients lost to follow-up. Overall, all patients with follow-up achieved a cranial contour with good symmetry to the unaffected side, as well as effective protection to the brain. CONCLUSIONS: Titanium mesh cranioplasty is an effective option for correcting pediatric cranial defects when autologous bone availability is limited and soft tissue coverage allows placement of an implant. The interim outcome for these patients is favorable with few complications and no evidence of growth restriction in the authors' series. Follow-up will be ongoing for these patients.

Tranexamic Acid Reduces Blood Loss in Craniosynostosis Surgery.

METHODS: The authors retrospectively reviewed 79 patients with craniosynostosis who underwent either bifrontal or biparietal-occipital calvarial vault remodeling before institution of tranexamic acid (TXA) administration (non-TXA group) and 35 patients after institution of TXA administration (TXA group). The patients were analyzed in 2 groups: all open calvarial vault remodeling patients (anterior and posterior) as a whole, and anterior vaults only as a subset analysis. Primary outcomes accessed were: total intraoperative blood transfused, postoperative blood transfused, and estimated blood loss (EBL). Secondary outcomes evaluated were length of stay in the pediatric intensive care unit and hospital length of stay. RESULTS: When comparing all open calvarial vault remodeling patients, patients who received TXA required significantly less total blood transfusion during their operation (264 cc TXA group versus 428 cc non-TXA, P < 0.0001). Patients who received TXA required no blood transfusions postoperatively, compared with the non-TXA group, in which 45% of patients required postoperative blood transfusion. Weight-based EBL was also significantly lower in those patients receiving TXA (25 cc/kg in the TXA group versus 34 cc/kg in the non-TXA group [P = 0.0143]). All patients required transfusion intraoperatively. Pediatric intensive care unit length of stay was shorter in the TXA group, but there was no significant difference in total hospital length of stay. These findings also reached statistical significance when comparing only the anterior vault patients. CONCLUSION: Intraoperative TXA administration has a correlation with reduced blood transfusion requirements, as well as EBL, in patients undergoing open calvarial vault remodeling. There were no adverse events related to TXA administration.

In vitro hydrodynamic, transient, and overtime performance of a miniaturized valve for hydrocephalus.

Reliable cerebrospinal fluid (CSF) draining methods are needed to treat hydrocephalus, a chronic debilitating brain disorder. Current shunt implant treatments are characterized by high failure rates that are to some extent attributed to their length and multiple components. The designed valve, made of hydrogel, steers away from such protracted schemes and intends to provide a direct substitute for faulty arachnoid granulations, the brain's natural CSF draining valves, and restore CSF draining operations within the cranium. The valve relies on innate hydrogel swelling phenomena to strengthen reverse flow sealing at idle and negative pressures thereby alleviating common valve failure mechanisms. In vitro measurements display operation in range of natural CSF draining (cracking pressure, PT ~ 1-110 mmH2O and outflow hydraulic resistance, Rh ~ 24-152 mmH2O/mL/min), with negligible reverse flow leakage (flow, QO > -10 µL/min). Hydrodynamic measurements and over-time tests under physically relevant conditions further demonstrate the valve's operationally-reproducible properties and strengthen its validity for use as a chronic implant.

Transvenous to arterial Onyx embolization.

BACKGROUND/OBJECTIVE: Transarterial infusion of Onyx is now widely used in the treatment of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs). Transvenous Onyx embolization is rarely performed, and usually in cases of carotid cavernous fistulas. We describe a novel technique of transvenous Onyx embolization in the treatment of three high risk DAVFs and one vein of Galen (VOG) AVM. METHODS: Cases were evaluated with specific attention to technical caveats, clinical indications, and complications. Patients were treated during 2011-2012 by two operators (FCA and CGM). Standard transfemoral venous approaches were employed in order to obtain access into the draining venous system in all cases. RESULTS: Four female patients, aged 5 months to 68 years, were treated. Two patients, one presenting with headache and the other with a bruit, demonstrated high risk DAVFs involving the transverse-sigmoid sinuses. One patient, who was asymptomatic, manifested a high risk ethmoidal DAVF that was discovered incidentally during treatment of a basilar aneurysm. The final patient presented with symptoms of a pineal region mass and was found to have a VOG AVM. In all cases, a microcatheter was navigated through the draining venous pouch and into the ostium of an arterial feeder. A single Onyx infusion from this position filled multiple arterial feeders and resulted in cures in the first three patients and a significant reduction in AVM nidus in the fourth patient. No complications occurred. CONCLUSIONS: Transvenous Onyx infusion into a single arterial feeder can produce retrograde embolization of numerous other arterial feeders supplying high risk DAVFs and complex cerebral AVMs. This technique appears to be safe and potentially curative in select cases.

Miniaturized passive hydrogel check valve for hydrocephalus treatment.

Improvements in cerebrospinal fluid (CSF) draining techniques for treatment of hydrocephalus are urgently sought after to substitute for current CSF shunts that are plagued by high failure rates. The passive check valve aims to restore near natural CSF draining operations while mitigating possible failure mechanisms caused by finite leakage or low resilience that frequently constrain practical implementation of miniaturized valves. A simple hydrogel diaphragm structures core passive valve operations and enforce valve sealing properties to substantially lower reverse flow leakage. Experimental measurements demonstrate realization of targeted cracking pressures (PT ≈ 20-110 mmH2O) and operation at -800 <; ΔP <; 600 mmH2O without observable degradation or leakage.

Evaluation of operative procedures for symptomatic outcome after decompression surgery for Chiari type I malformation.

The wide spectrum of symptoms and radiographic findings in patients with Chiari I malformation makes the decision to proceed with intervention controversial. We evaluated symptomatic outcomes using diverse surgical techniques in 104 patients who underwent decompression surgery. The symptoms of most patients improved. Patients with syringomyelia showed less symptomatic improvement; however, syringomyelia was not associated with postoperative symptomatic worsening. Durotomy was performed in 97.1% and arachnoid opening was performed in 60.6% with visualization of the fourth ventricle in 51.9% of patients. Neither arachnoid opening nor fourth ventricle visualization was associated with the clinical outcome. Duraplasty was performed in 94.2% of patients. A Chiari plate was used in 13.4% of patients and was associated with favorable outcomes. Use of postoperative steroids or muscle relaxants was not associated with outcome. Syringomyelia showed a 62.5% improvement rate on postoperative MRI. In conclusion, bony decompression and dural opening are important aspects of Chiari I surgery, with symptomatic improvement observed in most patients.

Surgical and endovascular treatment of pediatric spinal arteriovenous malformations.

OBJECTIVE: Pediatric spinal arteriovenous malformations (AVMs) are rare and complex lesions to treat. There are few reports of the endovascular and microsurgical treatment of these lesions in the pediatric population, and the treatment outcomes of these patients are not well described. The aim of this study was the clinical and radiographic outcomes of spinal AVMs in pediatric patients treated via endovascular and microsurgical modalities. METHODS: We identified nine children (5 boys, 4 girls; average age 11 years, range 3-17 years) treated for spinal AVMs between 1998 and 2010. Their charts were reviewed. RESULTS: Spinal AVMs most frequently involved the thoracic spinal cord. Four patients had associated Klippel-Trènaunay-Weber syndrome and one had hereditary hemorrhagic telangiectasia. There were two intramedullary, four conus medullaris, and three mixed extradural-intradural lesions. The most common presenting signs and symptoms were subarachnoid hemorrhage (n = 3) and paraparesis (n = 5). Endovascular intervention was used exclusively in two patients, and combined endovascular and microsurgical intervention was used in four patients. Surgery was the sole treatment in three patients with excellent results. There were two treatment-related complications: one case of subarachnoid hemorrhage and one case of scrotal swelling. The mean follow-up was 28.5 months and the median was 8 months (range, 1-65 months). The mean pretreatment World Health Organization (WHO)/Zubrod score was 2.4 (range, 1-4), and the mean post-treatment score was 1.4 (range, 0-4). One patient (11%) had a recurrence. CONCLUSIONS: Pediatric spinal AVMs require complex combined microsurgical and endovascular techniques to achieve favorable outcomes.