Effect of allograft patch closure on incidence of spinal inclusion cyst formation following open fetal myelomeningocele repair.

OBJECTIVE: The aim of this study was to evaluate the incidence of spinal inclusion cyst (sIC) formation after open fetal myelomeningocele (fMMC) repair and the effect of dural patch closure. METHODS: The authors conducted a retrospective review of patients who underwent open fMMC repair at their institution between March 2011 and June 2020. All patients met the criteria for intervention defined by the Management of Myelomeningocele Study (MOMS). The primary outcomes investigated were development of sIC and need for surgical intervention. Secondary outcomes included need for CSF diversion, extent of reversal of hindbrain herniation, and ambulatory status. RESULTS: Of 56 patients who underwent open fMMC repair, 52 had adequate spinal imaging for review. Twelve of these patients (23%) developed sIC (95% CI 0.11-0.35). Six patients experienced symptoms and required surgical detethering with sIC resection. Six additional patients had evidence of sIC on surveillance MRI but remained asymptomatic. The authors found a statistically significant relationship between the use of a dural allograft patch and sIC formation (p = 0.05). In terms of sIC development, there was no statistically significant difference between patients who underwent primary closure and those who received an allograft at the level of the fascia (p = 0.34) or skin (p = 0.26). The rate of hydrocephalus requiring CSF diversion was 52%. Interestingly, 98% of patients had improvement in extent of hindbrain herniation. Dural patch closure did not have any effect on the rate of progressive hydrocephalus (p = 0.33) or degree of reversal of hindbrain herniation (p > 0.99). CONCLUSIONS: This study suggested that children with prenatally repaired MMC are at higher risk for development of sIC and associated symptoms than those who undergo postnatal repair. The presentation of symptoms was also earlier in these patients than previously reported after postnatal repair. The use of a dural allograft patch appears to have a positive correlation with sIC formation. Future investigations evaluating the incidence of sIC after fetoscopic MMC repair, in which primary dural closure typically cannot be achieved and a dural patch is most often utilized, will be helpful in facilitating prenatal counseling for patients considering fetal intervention.

Responsive neurostimulation device therapy in pediatric patients with complex medically refractory epilepsy.

OBJECTIVE: Pediatric epilepsy is characterized as drug resistant in 20%-30% of patients and defined as persistent seizures despite adequate treatment with two first-line antiepileptic medications. The American Academy of Neurology advocates surgical options earlier in the treatment of epilepsy to provide long-term seizure reduction. The new development of minimally invasive approaches has recently allowed for surgical options to patients not previously deemed surgical candidates. These may include patients with bilateral, deep, eloquent, or poorly localizing epileptogenic foci. To this end, responsive neurostimulation (RNS) is an FDA-approved closed-loop neuromodulation device for adjuvant treatment of adults with medically intractable epilepsy arising from one or multiple foci. METHODS: In this study, the authors describe their initial institutional experience with the use of RNS in pediatric patients with drug-resistant epilepsy. An IRB-approved retrospective review was conducted of 8 pediatric patients who underwent RNS implantation at Cincinnati Children's Hospital Medical Center between 2019 and 2021. RESULTS: Eight patients met the inclusion criteria for the study. The average age at the time of surgery was 14.7 years (range 8-18 years) with a mean follow-up of 16.5 months. All patients underwent invasive monitoring with stereo-EEG, subdural grid placement, or a combination of both. All patients had either bilateral or eloquent cortex targets. Trajectories were based on noninvasive (phase 1) and invasive (phase 2) seizure onset zone localization data. Four (50%) of the 8 patients underwent surgical intervention for epilepsy prior to RNS placement. RNS electrodes were placed with robot-assisted guidance in a hybrid operating room with intraoperative CT and electrocorticography. The authors demonstrated individualized RNS electrode trajectory and placement with targets in the amygdala/hippocampus, bilateral insula, bilateral parietal and occipital targets, and frontoparietal regions for a total of 14 implanted electrodes. One adverse event occurred, a wound infection requiring return to the operating room for removal of the RNS implant. All patients demonstrated a reduction in seizure frequency. All patients achieved > 50% reduction in seizure frequency at last follow-up. CONCLUSIONS: RNS implantation in carefully selected pediatric patients appears safe and efficacious in reducing seizure burden with a low rate of operative complications.

Predicting neurosurgical clearance in the polytrauma patient with concomitant traumatic brain injury.

The goal of this study is to develop a model based on previously used prognostic predictors in traumatic brain injury (TBI) patients with polytrauma, which will facilitate the decision-making of whether to clear these patients for non-cranial surgery. Data of eligible patients was obtained from a trauma database at a Level I trauma and academic tertiary referral center in the United States. The number of days seen by the neurosurgical service prior to clearance, injury severity score (ISS), post-trauma day 0 (PTD 0) of Glasgow Coma Score (GCS), intracranial pressure (ICP) score and computed tomography (CT) score, as well as the changes in GCS, ICP score and CT score between PTD 0 and day of clearance were the variables used in developing the model. The Neurosurgical Clearance Model (NCM) was developed using data from 50 patients included in the study. Patients were cleared by neurosurgeons 1.6 days later than it would appear possible based on a retrospective review of the patients' clinical conditions. A single model equation was developed, the ultimate result of which is a clearance probability value. The best cutoff clearance probability value was found to be 0.584 (or 58.4%) using Receiver Operator Characteristic curve analysis. Our data suggests that neurosurgeons are risk-averse in clearing polytrauma patients for non-cranial surgery. This pilot NCM, if reproduced and validated by other groups and in larger prospective studies, may become a useful tool to assist clinicians in this often-difficult decision-making process.

Magnetic Resonance-Guided Laser Interstitial Thermal Therapy for Palliative Rhizotomy: A Novel Technical Application.

BACKGROUND: Spastic cerebral palsy is caused by an insult to the developing brain. Various medical and surgical procedures are used to reduce tone. OBJECTIVE: To describe a novel method of magnetic resonance-guided laser interstitial thermal ablation for palliative rhizotomy. METHODS: Patients treated at a single institution with percutaneous rhizotomy using magnetic resonance-guided laser interstitial thermal therapy were identified. Preoperative and postoperative Modified Ashworth Scale scores were collected as well as procedural information. RESULTS: Two male children (7.8 and 19 yr, respectively) with spastic quadriparesis were treated using this technique. Neither patient experienced surgical or perioperative complications, and both were discharged from the hospital within 48 h. Each of them demonstrated improvement in his Modified Ashworth Scale score with no need for retreatment for spasticity at last follow-up. CONCLUSION: These 2 cases illustrate a novel technique for treating spasticity in the setting of cerebral palsy. Further study of this technique in additional patients, and comparison with traditional methods of surgical tone reduction, are warranted.

Surgical Adjuncts for Glioblastoma.

Although surgical resection of the solid tumor component of glioblastoma has been shown to provide a survival advantage, it will never be a curative procedure. Yet, systemically applied adjuvants (radiation therapy and chemotherapy) also are not curative and their options are limited by the inability of most agents to cross the blood-brain barrier. Direct delivery of adjuvant therapies during a surgical procedure potentially provides an approach to bypass the blood-brain barrier and effectively treat residual tumor cells. This article summarizes the approaches and therapeutics that have been evaluated to date, and challenges that remain to be overcome.

Increased complications without neurological benefit are associated with prophylactic spinal cord untethering prior to scoliosis surgery in children with myelomeningocele.

PURPOSE: Children with myelomeningocele (MMC) are at increased risk of developing neuromuscular scoliosis and spinal cord re-tethering (Childs Nerv Syst 12:748-754, 1996; Neurosurg Focus 16:2, 2004; Neurosurg Focus 29:1, 2010). Some centers perform prophylactic untethering on asymptomatic MMC patients prior to scoliosis surgery because of concern that additional traction on the cord may place the patient at greater risk of neurologic deterioration peri-operatively. However, prophylactic untethering may not be justified if it carries increased surgical risks. The purpose of this study was to determine if prophylactic untethering is necessary in asymptomatic children with MMC undergoing scoliosis surgery. METHODS: A multidisciplinary, retrospective cohort study from seven children's hospitals was performed including asymptomatic children with MMC < 21 years old, managed with or without prophylactic untethering prior to scoliosis surgery. Patients were divided into three groups for analysis: (1) untethering at the time of scoliosis surgery (concomitant untethering), (2) untethering within 3 months of scoliosis surgery (prior untethering), and (3) no prophylactic untethering. Baseline data, intra-operative reports, and 90-day post-operative outcomes were analyzed to assess for differences in neurologic outcomes, surgical complications, and overall length of stay. RESULTS: A total of 208 patients were included for analysis (mean age 9.4 years, 52% girls). No patient in any of the groups exhibited worsened motor or sensory function at 90 days post-operatively. However, comparing the prophylactic untethering groups with the group that was not untethered, there was an increased risk of surgical site infection (SSI) (31.3% concomitant, 28.6% prior untethering vs. 12.3% no untethering; p = 0.0104), return to the OR (43.8% concomitant, 23.8% prior untethering vs. 17.4% no untethering; p = 0.0047), need for blood transfusion (51.6% concomitant, 57.1% prior untethering vs. 33.8% no untethering; p = 0.04), and increased mean length of stay (LOS) (13.4 days concomitant, 10.6 days prior untethering vs. 6.8 days no untethering; p < 0.0001). In multivariable logistic regression analysis, prophylactic untethering was independently associated with increased adjusted relative risks of surgical site infection (aRR = 2.65, 95% CI 1.17-5.02), unplanned re-operation (aRR = 2.17, 95% CI 1.02-4.65), and any complication (aRR = 2.25, 95% CI 1.07-4.74). CONCLUSION: In this study, asymptomatic children with myelomeningocele who underwent scoliosis surgery developed no neurologic injuries regardless of prophylactic untethering. However, those who underwent prophylactic untethering were more likely to experience SSIs, return to the OR, need a blood transfusion, and have increased LOS than children not undergoing untethering. Based on these data, prophylactic untethering in asymptomatic MMC patients prior to scoliosis surgery does not provide any neurological benefit and is associated with increased surgical risks.

Impaired fasting glucose and impaired glucose tolerance have distinct lipoprotein and apolipoprotein changes: the insulin resistance atherosclerosis study.

CONTEXT: Cardiovascular risk is increased in individuals with impaired glucose tolerance (IGT) and impaired fasting glucose (IFG); however, those with IGT appear to be at greater risk. Lipoprotein abnormalities occur also in the prediabetic state. OBJECTIVE: The authors examined lipoprotein composition in IGT and IFG. DESIGN AND SETTING: Cross-sectional analysis of a large epidemiological study was done. PARTICIPANTS: The Insulin Resistance Atherosclerosis Study had a total of 1107 participants. MAIN MEASURES: Lipoproteins and apolipoproteins were measured by conventional methods and lipoprotein composition by nuclear magnetic resonance spectroscopy. RESULTS: Compared with normal glucose tolerance, apolipoprotein B (105.2 vs 99.8 mg/dL, P < .05) was high in isolated IFG, triglyceride (1.48 vs 1.16 mmol/L, P < .001) was high in isolated IGT, and high-density lipoprotein cholesterol was low in combined IFG/IGT (1.12 vs 1.26 mmol/L, P < .001). Nuclear magnetic resonance spectroscopy revealed additional changes: increased total low-density lipoprotein (LDL) particles (1190 vs 1096 nmol/L, P < .01) in isolated IFG; increased large very-low-density lipoprotein (3.61 vs 2.47 nmol/L, P < .01) and small LDL subclass particles (665 vs 541 nmol/L, P < .05) and decreased large LDL subclass particles (447 vs 513 nmol/L, P < .01) in isolated IGT; and decreased large high-density lipoprotein subclass particles in combined IFG/IGT (4.24 vs 5.39 µmol/L, P < .001). CONCLUSIONS: Isolated IFG is characterized by increased apolipoprotein B and total LDL particles, whereas isolated IGT is associated with increased triglycerides, large very-low-density lipoprotein subclass particles, and structural remodeling of LDL particles. These results may help to explain differences in cardiovascular disease risk in the prediabetic state.