Maximizing Sacral Chordoma Resection by Precise 3-Dimensional Tumor Modeling in the Operating Room Using Intraoperative Computed Tomography Registration with Preoperative Magnetic Resonance Imaging Fusion and Intraoperative Neuronavigation: A Case Series.

INTRODUCTION: The primary treatment for patients with sacral chordoma is en bloc surgical resection with negative margins, which has been shown to reduce local recurrence and tumor-related morbidity. Here we describe the use of intraoperative neuronavigation using preoperative spine magnetic resonance imaging fused to intraoperative computed tomography (CT) to create 3-dimensional tumor reconstructions in the operating room for intraoperative identification of bone and soft-tissue margins for maximal safe tumor resection. METHODS: A single-institution retrospective chart review was completed to encompass our experience of 6 consecutive patients who had sacral chordoma resections using our described navigation protocol. We collected data on patient demographics, previous surgeries, radiation therapy, preoperative examination, spinal levels involved, dural involvement, estimated blood loss, surgery time, tissue diagnosis, follow-up, postoperative examination, complications, and recurrence. Primary outcome was en bloc resection with negative margins as planned preoperatively. RESULTS: Negative surgical margins were achieved in 5 of 5 patients, who were preoperatively planned for en bloc resection with negative margins. The most common levels involved were S4-S5. All patients had a stable or improved neurologic examination after en bloc surgical resection. The average follow-up was 5.4 months ± 84.6 days. No patient had residual or recurrent tumor at last follow-up. CONCLUSIONS: Magnetic resonance imaging-CT fusion and 3-dimensional reconstruction techniques using an intraoperative CT scanner with image-guided navigation to aid preoperative planning and surgical resection of sacral chordomas are not well represented in the literature. This technique can be used for planning en bloc surgical resections and for more precisely identifying tumor margins intraoperatively.

Awake Microvascular Decompression for Trigeminal Neuralgia: Concept and Initial Results.

BACKGROUND: In this initial series, we evaluated the use of microvascular decompression (MVD) under an awake anesthesia protocol ("awake" MVD) to assess whether intraoperative pain evaluation can identify and mitigate insufficient decompression of the trigeminal nerve, improving surgical outcomes, and possibly expand the indications of MVD in patients with comorbidities that would preclude the use of general endotracheal anesthesia (GEA). METHODS: An Institutional Review Board-approved prospective study of 10 consecutive adults who underwent MVD for trigeminal neuralgia (TN) was conducted. The primary outcome measure was postoperative TN pain quantified on the Barrow Neurological Institute (BNI) Pain Severity Scale. RESULTS: The median patient age was 65.5 years, with a female:male ratio of 6:4. All 10 patients tolerated the procedure well and did not require GEA intraoperatively or postoperatively. Nine patients had a successful surgical outcome (BNI score I, n = 5; BNI score II, n = 4). One patient did not have pain relief (BNI score IV). This same patient also developed a pseudomeningocele, which was the sole surgical complication observed in this series. One patient experienced recurrence of pain at 11 months, with BNI score increasing from I to II. The median duration of follow-up was 16.5 months. Two patients did not experienced resolution of evoked pain during intraoperative awake testing following decompression. Further intraoperative exploration revealed secondary offending vessels that were subsequently decompressed, leading to resolution of pain. CONCLUSIONS: Intraoperative awake testing for treatment efficacy may increase the success rate of MVD by rapidly identifying and mitigating insufficient cranial nerve V decompression.

First 60 fetal in-utero myelomeningocele repairs at Saint Louis Fetal Care Institute in the post-MOMS trial era: hydrocephalus treatment outcomes (endoscopic third ventriculostomy versus ventriculo-peritoneal shunt).

INTRODUCTION: The published results of the Management of Myelomeningocele Study (MOMS) trial in 2011 showed improved outcomes (reduced need for shunting, decreased incidence of Chiari II malformation, and improved scores of mental development and motor function) in the fetal prenatal repair group compared to the postnatal group. Historically, endoscopic third ventriculostomy (ETV) remains as a controversial hydrocephalus treatment option with high failure rates in pediatric patients with a history of myelomeningocele (MMC). We report hydrocephalus treatment outcomes in the fetal in-utero myelomeningocele repair patients who underwent repair at our Saint Louis Fetal Care Institute following the MOMS trial. We looked carefully at ETV outcomes in this patient population and we identified risk factors for failure. METHODS: At our Saint Louis Fetal Care Institute, we followed the maternal and fetal inclusion and exclusion criteria used by the MOMS trial. The records of our first 60 fetal MMC repairs performed at our institute between 2011 and 2017 were examined. We retrospectively reviewed the charts, prenatal fetal magnetic resonance imaging (MRI) and ultrasound (US) imaging findings, postnatal brain MRI, and Bayley neurodevelopment testing results for infants and children who underwent surgical treatment of symptomatic hydrocephalus (VP shunt versus ETV). Multiple variables possibly related to ETV failure were considered for identifying risk factors for ETV failure. RESULTS: Between May 2011 and March 2017, 60 pregnant female patients underwent the prenatal MMC repair for their fetuses between 20 and 26 weeks' gestational age (GA) utilizing the standard hysterotomy for exposure of the fetus, and microsurgical repair of the MMC defect. All MMC defects underwent successful in-utero repair, with subsequent progression of the pregnancy. At the time of this study, 58 babies have been born, 56 are alive since there were 2 mortalities in the neonatal period due to prematurity. One patient was excluded given lack of consent for research purposes. From the remaining 55 patient included in this study, a total of 30 infants and toddlers underwent treatment of hydrocephalus (ETV and VPS groups). Twenty-five patients underwent ETV (24 primary ETV and 1 after shunt failure). Nineteen patients underwent shunt placements (6 primary/13 after ETV failure). Mean GA at time of MMC repair for the ETV group was 24 + 6/7 weeks (range 22 + 4/7 to 25 + 6/7). Mean follow up for patients who had a successful ETV was 17.25 months (range 4-57 months). Bayley neurodevelopmental testing results were examined pre- and post-ETV. Overall ETV success rate was 11/24 (45.8%) at the time of this study. The total number of patients who underwent shunt placement was 19/55 (34.5%), while shunting rate was 40% in the MOMS trial. Using a simple logistic regression analysis to identify predictors of ETV failure, ETV age ≤6 months and gestational age ≥23 weeks at repair of myelomeningocele were significant predictors for ETV failure while in-utero ventricular stability ≤4 mm and in-utero ventricular size post-repair ≤15.5 mm were significant predictors for ETV success. None of the listed variables independently predicted classification into ETV success versus ETV failure groups when entered into multiple logistic regression analysis. CONCLUSIONS: ETV, as an alternative to initial shunting, may continue to show promising results for treating fetal MMC repair patient population who present with symptomatic hydrocephalus during infancy and early childhood. Although our overall CSF diversion rate (ETV and VPS groups) in our fetal MMC group is higher than the MOMS trial, our shunting rate is lower given our higher incidence of patients with successful ETV. To our knowledge, this is the largest reported ETV series in patients who underwent fetal MMC repair. ETV deserves a closer look in the setting of improved hindbrain herniation in fetal in-utero MMC repair patients. In our series, young age (less than 6 months) and late GA at time of fetal MMC repair (after 23 weeks GA) were predictors for ETV failure, while in-utero stability of ventricular size (less than 4 mm) and in-utero ventricular size post-repair ≤15.5 mm were predictors for ETV success. Larger series and potential prospective randomized studies are required for further evaluation of risk factors for ETV failure in the fetal MMC patient population.