Background: PET imaging of [11C]ABP688 shows reduced hippocampal mGluR5 availability in mesial temporal lobe epilepsy (MTLE) patients, however the relation with post-surgical outcomes is unclear. Here, we tested whether [11C]ABP688 binding in hippocampal subfields vulnerable to glutamate excitotoxicity is related to post-surgical outcome. Methods: [11C]ABP688-PET was obtained from 31 unilateral MTLE patients and 30 controls. Hippocampal subfields were automatically segmented into 1) CA1-3, 2) CA4/dentate gyrus (DG), 3) Subiculum and manually corrected. Partial volume corrected [11C]ABP688 non-displaceable binding potential (BPND) was calculated in the subfields and compared between seizure-free and non-seizure-free patients. Results: [11C]ABP688 BPND was significantly reduced in ipsilateral CA1-3 & CA4/DG (p<0.001) compared to controls. No difference was seen in Subiculum. Ipsilateral CA1-3 [11C]ABP688 BPND was lower in seizure-free (p=0.012; Engel Ia, n=13) vs non-seizure- free (Engel Ic-III, n=10) patients, and this effect was independent of subfield volume. In a subset of patients with [18F]FDG-PET, CA1-3 [11C]ABP688 BPND was significantly lower in seizure-free patients (p=0.03), while no difference was found for [18F]FDG uptake. Conclusions: Reduced CA1-3 mGluR5 availability was associated with post-surgical seizure-freedom independent of atrophy and hypometabolism. Thus, [11C]ABP688-PET may offer a potential biomarker for surgical outcomes and may be particularly relevant for pre-surgical workup in MRI- and [18F]FDG-negative MTLE patients.

Background: CIDP is an autoimmune polyneuropathy. Antibodies against the Node of Ranvier have been described, NF155,NF140/186 and contactin-1. Methods: A retrospective review of patients with CIDP who tested positive for antinodal/paranodal antibodies via Western blot were evaluated. We have included 20 sero-negative CIDP patients. All patients met definite or probable EFNS criteria. clinical, electrophysiological data and response to treatment were obtained. Results: Forty-five patients tested positive for the antibodies. Sixteen were positive for NF155,11 for NF140, 5 for CNTN1,11 were double positive for NF155 and NF140, and 3 were triple positive for NF155, NF140 and CNTN. Age of onset was similar in both seronegative (53.9 ± 3.1 yrs.) versus seropositive(52.3 ± 2.4 yrs.).Chronic presentation manifested in 85% of seronegative, 80% of seropositivepatients.Intrestingly,all triple-positive patients presented with a more acute presentation(i.e,<8 wks.)7/20 seronegative (35%),1/16 NF155, 6/11 NF140,1/5 contactin, 2/11 of doublepositive, 3/3 of triple-positive (28%,13/46) responded to IVIg. Conclusions: No major clinical or electrophysiological differences between groups. triple-positive patients showed 100% response to IVIg.These results cast doubt on the specificity of the Western blot as a clinico-electrophysiologic discriminator. Future testing with cellbased assays will likely provide a robust measure that will guide treatment decision.

Background: The coronavirus disease 2019 (COVID-19) pandemic has led the implementation of institutional infection control protocols. This study will determine the effects of these protocols on outcomes of acute ischemic stroke (AIS) patients treated with endovascular therapy (EVT). Methods: Uninterrupted time series analysis of the impact of COVID-19 safety protocols on AIS patients undergoing EVT. We analyze data from prospectively collected quality improvement databases at 6 centers from March 11, 2019 to March 10, 2021. The primary outcome is 90-day modified Rankin Score (mRS). The secondary outcomes are angiographic time metrics. Results: Preliminary analysis of one stroke center included 214 EVT patients (n=150 pre-pandemic). Baseline characteristics were comparable between the two periods. Time metrics “last seen normal to puncture” (305.7 vs 407.2 min; p=0.05) and “hospital arrival to puncture” (80.4 vs 121.2 min; p=0.04) were significantly longer during pandemic compared to pre-pandemic. We found no significant difference in 90-day mRS (2.0 vs 2.2; p=0.506) or successful EVT rate (89.6% vs 90%; p=0.93). Conclusions: Our results indicate an increase in key time metrics of EVT in AIS during pandemic, likely related to infection control measures. Despite the delays, we found no difference in clinical outcomes between the two periods.

Background: MRI forms an imperative part of the diagnostic and treatment protocol for primary brain tumors and metastasis. Though conventional T1W MRI forms the basis for diagnosis at present, it faces several limitations. Machine learning (ML) algorithms require less expertise and provide better diagnostic accuracy. Methods: A systematic review of PubMed, Google Scholar, and Cochrane databases along with registries through 1980-2021 was done. Original articles in English evaluating Conventional MRI or ML algorithms. Data was extracted by 2 reviewers and meta-analysis was performed using bivariate regression model. Results: The study protocol was registered under PROSPERO. Twelve studies with 1247 participants were included for systematic analysis and three studies for meta-analysis. ML algorithms had better aggregate sensitivity and specificity (80%, 83.14%) than Conventional MRI (81.84%, 74.78%).The pooled sensitivity, specificity, DOR for the studies were 0.926 (95% CI, 0.840-0.926), 0.991 (95% CI, 0.955-0.998) and 1446.946 (312.634-6692.646) with AUC=0.904 under HSROC. On subgroup analysis, MRS and Random Forest Model had highest sensitivity and specificity (100%,100%;100%,100%), DSC MRI and Deep Neural Network had highest AUC (0.98,0.986). Conclusions: ML algorithm has superior diagnostic performance and faster diagnostic capability once trained than conventional imaging for brain tumors. It has immense potential to be the standard of care in the future.

Background: Granulomatosis with polyangiitis (GPA) is a rare disease of unknown cause. The multitude of manifestations presents significant diagnostic challenges. This is a unique case of GPA with sinonasal, airway, skull base, petrous bones, vascular, and brain parenchyma involvement. Methods: We present a case of a 45-year-old female with a several day history of headache and left hearing loss. MRI brain demonstrated a large erosive enhancing soft process in the sinonasal cavity and nasopharynx. Results: She developed new ipsilateral rightward tongue deviation. A second MRI demonstrated disease progression. It showed posterior pharyngeal wall ulceration, involvement of the skull base foramina, petrous bones, and central bony skull erosion. It demonstrated right hemiglossal edema secondary to right hypoglossal nerve compression at the skull base. There was enhancing soft tissue partially encasing the left petrous internal carotid artery and more extensively encasing and narrowing bilateral intradural vertebral arteries with associated brainstem edema secondary to direct mass effect and new left occipital thromboembolic infarct. She underwent a nasopharyngeal biopsy which demonstrated acute inflammation on a background of GPA. Conclusions: There are no pathognomonic imaging characteristics for GPA. By recognizing the common and less-common imaging features, radiologists play a crucial role in both diagnosing and monitoring the disease activity.

Background: The purpose of this systematic review was to synthesize evidence based on existing studies on the ability of initial imaging to predict mortality in severe traumatic brain injuries (TBIs) in pediatric patients. Methods: An experienced librarian searched for all existing studies based on the inclusion and exclusion criteria. The studies were screened by two blinded reviewers. The data was extracted to calculate the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predicted value (NPV), area under the curve (AUC), and receiver operating characteristic (ROC) for extradural hematoma (EDH), subdural hematoma (SDH), traumatic subarachnoid hemorrhage (tSAH), skull fractures, and edema. Results: Of the 3277 studies included in the search, data could only be extracted from 22 studies. There were a total of 2219 patients, 747 females, and 1461 males. 564 patients died and 1651 survived. 293 patients had SDH, 76 had EDH, 347 had tSAH, 244 had skull fractures, and 416 had edema. Seven of the studies had sufficient data to calculate the AUC, ROC, and generate a forest plot for the imaging findings. Conclusions: Out of the different CT scan findings, brain edema had the highest SN, PPV, NPV, and AUC. EDH had the highest SP to predict in hospital mortality.

Background: Endovascular approaches are typically preferred to open surgical techniques for symptomatic subclavian/innominate artery stenosis. Due to individual patient anatomy, endovascular treatment from a conventional femoral arterial approach can be technically challenging. Our alternative technique using a combined radial to femoral artery approach can facilitate an otherwise challenging revascularization procedure. Methods: Retrospective analysis between November 2017 to March 2021 yielded five procedures (in four patients) using a combined radial to femoral “through and through” access and stenting technique. Results: All patients presented with hypoperfusion symptoms, either to their extremities, brain, or both. Technical success was achieved in 100% of the five vessels treated in four patients with symptomatic subclavian/innominate artery stenosis using this approach. One of the patients developed a recurrent stenosis after 40 months, requiring a repeat procedure. Three patients received treatment to the left subclavian artery and one to the innominate artery. All of the patients experienced marked symptomatic improvement without significant complications. Conclusions: A combined radial to femoral “through and through” access technique is a simple and safe method to achieve successful recanalization of high grade symptomatic ostial stenoses of the subclavian and innominate arteries.

Background: Chronic subdural hematoma (CSDH) is of the most encountered neurosurgical cases, predominantly in older individuals. Surgical drainage remains the mainstay, yet is challenged by variable recurrence rates. Less invasive methods of embolization of the middle meningeal artery (EMMA) could reduce the recurrence rates. Before adopting a newer treatment (EMMA), it is prudent to establish the outcomes from surgical drainage. The purpose of this study is to assess the clinical outcome and recurrence risk in surgically treated CSDH patients. Methods: A retrospective search of our surgical database was done to identify CSDH patients undergoing surgical drainage in 2019-2020. Demographic and clinical details were collected through chart review and a qualitative statistical analysis was performed. Results: A total of 136 patients (mean age-68 years; range-21-100 years; Male-105) with CSDH underwent surgical drainage with repeat surgery in 11.8%(n=16). Periprocedural mortality and morbidity were 8.8%(n=12) and 20.6%(n=28), respectively. No radiological follow-up was seen in 30(22%) of patients. Of those with follow-up, recurrence was seen in 21.7%(n=23). Mean hospital stay was 9.64 days. Conclusions: Our retrospective study showed periprocedural morbidity (20.6%) and mortality (8.8%) with a 21.7% risk of recurrence. This is likely due to older patients but is in keeping with what is reported in the literature.

Background: Contrast induced encephalopathy (CIE) is an underrecognized, adverse effect of contrast administration during endovascular procedures. A paucity of literature exists regarding CIE following treatment of cerebrovascular disease. As such, we sought to describe our institutional experience with this entity. Methods: We searched our neurovascular database for instances of CIE following endovascular therapy for cerebrovascular disease. We extracted patient data, including demographics, comorbidities, procedural data, symptoms, radiological findings, and treatment. Informed consent was obtained in all cases. Data was analyzed using descriptive statistics. Results: Two patients underwent coiling of cerebral aneurysms; four were treated for ischemic stroke (thromboembolism or large artery atherosclerosis). Mean age was 67.2 years. Risk factors for microvascular dysfunction were identified for most patients: hypertension (100%), obesity (83%), dyslipidemia (83%), prior stroke (83%), renal disease (80%), and connective tissue disorders (33%). Mean operative duration: 284.5 minutes. Mean contrast volume: 285.7 mL. Decreased level of consciousness and lateralizing neurological deficits were the most common CIE-related symptoms. Treatments included intravenous fluids, corticosteroids, and anti-hypertensives. Radiographic findings included effaced cortical sulci, parenchymal edema, and cortical/subarachnoid contrast enhancement. Conclusions: Here, we describe our institutional experience with CIE following endovascular therapy for cerebrovascular disease. We hypothesize that CIE may be facilitated by pre-existing microvascular pathology.

Background: Ruptured Intracranial Infected Aneurysms (IIAs) are relatively rare, but they portend high mortality. To our knowledge, there are no Canadian case-series on IIA, as well there is a relative paucity of international published experiences. Our purpose is to share the experience of a single Canadian tertiary centre in managing ruptured IIA and to conduct a systematic review. Methods: We did a retrospective case review series of adult patients with ruptured IIA treated at our institution. Secondly, we conducted a systematic review of literature on ruptured IIA between 2011-2021 inclusive. Results: At our institution, of a total 8 cases with ruptured IIA, 4 were treated endovascularly and 2 by surgical bypass. For the systematic review, we included 9 non-comparative studies with a total of 509 patients (318 males) and at least 437 ruptured IIA aneurysms. Favourable outcome was specified for 63.3% of patients (n=57). Regarding ruptured IIA, favourable clinical outcome was described in 59.3% (n=16). Conclusions: This study highlights a single Canadian tertiary centre experience in the management of IIA and compares it to the global trends of the last 10 years in a systematic review.

Background: There is presently no cure for locomotor deficits after spinal cord injury (SCI). Very few therapies effectively target the brain due to poor understanding of the brain’s role post-SCI. Newly developed tissue clearing techniques have permitted unbiased three-dimensional circuit analysis, opening new opportunities for SCI-related brain interrogation. Methods: We established a novel brain interrogation pipeline by optimizing mouse brain clearing, imaging, and atlas registration. We leveraged a spontaneous recovery lateral hemisection model to analyze whole brain cell activity and connectivity with the lumbar cord using cFos immunolabelling and virus-mediated projection tracing. We identified a functionally and anatomically dynamic region correlating with recovery and interrogated its locomotor role with optogenetics. We assessed deep brain electrical stimulation (DBS) of this region in a more clinically relevant rat contusion SCI using an established bipedal robotic interface. Results: We unexpectedly uncovered the lateral hypothalamus (LH) to functionally and anatomically correlate with recovery. LHVglut2 optogenetic stimulation significantly augmented locomotor function. LH DBS in rats acutely robustly augmented bipedal locomotion post-SCI. Conclusions: This is the first demonstration of the LH’s role in locomotion post-SCI and is a novel DBS target that robustly augmented locomotor function, dependent on LH glutamatergic cells. LH DBS may be a promising intervention in humans.

Background: Therapeutic response from subthalamic nucleus (STN) deep brain stimulation (DBS) for Parkinson disease (PD) has been associated with proximity to an ideal target, commonly in the dorsal sensorimotor STN. Automated registration and atlas-based segmentation has allowed for contact localization within STN subnuclei. We sought to apply these methods to characterize the spatial distribution of our active contact placements. Methods: We conducted a retrospective analysis of 55 patients who underwent bilateral STN DBS for PD. Post-operative CT/MRI scans were non-linearly registered into a standard space, and DBS-electrodes were localized using Lead-DBS. 3-dimensional meshes from a segmented atlas (Ewert 2017) were utilized. Analysis was performed in MATLAB R2019b. Results: Mean active contacts were within sensorimotor STN bilaterally, located posteroinferiorly compared to reported ideal targets. Centroids fell within (left/right): sensorimotor (46%/40%), associative (22%/22%), limbic (0%/2%) and outside STN (32%/36%). Principal components analysis demonstrated most spatial variance is explained by the first component (left 65.8%, right 61.9%). Conclusions: We obtained contact locations in relation to STN subnuclei, allowing for an anatomically guided approach to our analysis. 66% of the active contacts were located within the STN, and most of the spatial variation occurred along a single dimension. Future directions include utilizing subnuclei localizations to investigate clinical outcomes.

Background: Gamma Knife radiosurgery for the treatment of refractory trigeminal neuralgia is recognized as an efficient intervention. The CyberKnife, a more recent frameless radiosurgery alternative, has not been studied as extensively for this condition. The aim of this study is to evaluate the clinical outcomes of a first CyberKnife radiosurgery treatment on patients with medically refractory trigeminal neuralgia. Methods: A retrospective study of 166 patients (168 cases) with refractory trigeminal neuralgia treated since 2009 with CyberKnife radiosurgery at the Centre Hospitalier de l’Université de Montreal (CHUM). Results: Adequate pain relief (Barrow Neurological Institute (BNI) pain scores I-IIIb) was achieved in 146 cases (86.9%). The median latency period before adequate pain relief was 35 days (range 0-202 days). The median duration of adequate pain relief was 15.8 months (range 0.6-85.0[DR1] [AG2] [AG3] [AG4] months). The actuarial rates of maintenance of adequate pain relief at 12, 36, and 60 months were 77.0%, 62.5%, and 50.2%, respectively. There was a new-onset or aggravation of facial numbness in 44 cases (26.2%). The maintenance of an adequate pain relief was more sustained in idiopathic cases in comparison to cases associated with multiple sclerosis (P< 0.001). Conclusions: In our experience CyberKnife radiosurgery for refractory trigeminal neuralgia is efficacious and safe.

Background: Radiofrequency rhizotomy is an efficacious technique for treatment of trigeminal neuralgia that is classically performed with the patient awake. Previous studies have investigated methods for both anatomic and neurophysiologic optimization for nerve targeting. Methods: We performed a retrospective review of prospectively collected data on patients undergoing radiofrequency rhizotomy under a general anesthetic. Electrodes are placed in the temporalis, masseter and one of mylohyoid or anterior belly of digastric muscles. We then localize of the correct subdivision of the trigeminal nerve. The division of the trigeminal nerve with pain shows a muscle response, which is not present in normal subdivisions. Results: A total of 23 radiofrequency rhizotomies were performed under general anesthetic. Abnormal conduction reflexes were present in all cases, and dissipated after lesioning. Pre-operative BNI pain scores were 4.1 ± 0.3, which dropped to 1.8 ± 1.9 post-op (p=0.003). Number of pain medications (2.9 ± 0.6 v. 1.3 ± 1.3, p=0.007) and number of patients with opioid usage (78.7% v. 21.7%, p=0.007) both decreased after rhizotomy. Conclusions: Using a novel conduction pathway, we have successfully been able to monitor radiofrequency rhizotomy in patients operated on under a general anesthetic, with promising preliminary results. Further work is needed to better evaluate this intervention.

Background: Trigeminal autonomic cephalgias (TAC) have been implicated in a multitude of intracranial mass lesions, including pituitary adenomas. Treatment of the associated pituitary adenoma has been reported to result in resolution of the secondary TAC. Methods: We conducted systematic search of the literature in accordance with PRISMA guidelines using Ovid Medline, Pubmed, Scopus, and Web of Science for TACs with associated pituitary lesions. We searched for all the relevant cases to detail the epidemiology, clinical phenotype of TAC, characteristics of the associated pituitary lesion including its hormonal profile, type of clinical intervention, and outcome. Results: Together with our case, 50 cases are reviewed. Prolactinomas were the most common hormone-producing adenomas (n=35; 71%). Few cases were non-functioning (n=3; 6%). Macroadenomas were predominant (n=30, 70%). Cavernous sinus extension was frequent (n=21; 54%). Medical intervention was the most employed form (n=31; 63%). Surgical intervention was carried in several cases (n=18; 37%). The success rate of medical management was high (n=25/31; 81%). Dopaminergic agonist therapy was the most common medical intervention (n=28; 90%). Conclusions: Secondary TACs with associated pituitary adenomas tend to have debilitating symptoms. The pathophysiology of the association is not entirely clear. Identifying the cause and employing the proper intervention is important to avoid unnecessary suffering.

Background: Post-dural puncture headache is a known complication of neuraxial anesthesia and acute subdural hematoma has been associated with unintentional dural puncture. Notably, a significant number of unintentional dural punctures remain unidentified. We present two contrasting cases of subdural hematoma (SDH) following labour epidural anesthesia with no sign of dural puncture at time of anesthesia. Patient 1 presented with headache post-partum day (PPD) six, SDH was identified PPD23, and blood-patch treatment performed PPD35. Patient 2 presented with headache immediately, had SDH identified PPD3, and placement of blood-patch PPD4. Methods: The cases are presented and the literature was reviewed for prior cases. Results: Patient 1 developed significant bilateral SDH with severe headache and right abducens palsy. Headache resolved post blood patch however surgical evacuation was required and the abducens palsy persisted. Patient 2 experienced resolution of symptoms two days post blood patch, the small unilateral SDH was managed conservatively, and had no neurological deficits. Conclusions: Headache is common in the postpartum period. The majority are primary etiology and benign. SDH is a rare but serious complication of neuraxial anesthesia, and the consequences may be devastating. Rapid identification and early treatment are essential to avoid severe neurological sequelae.

Background: 5-aminolevulinic acid (5-ALA) enhances intraoperative high grade glioma (HGG) tissue visualization. Despite promising randomized clinical trial data suggesting survival benefit for 5-ALA-guided HGG surgery, patient outcome efficacy is not universally accepted. Methods: We performed a systematic review of the literature to evaluate whether there is a beneficial effect upon survival and extent of resection from the utilization of 5-ALA in HGG surgery. Literature regarding 5-ALA usage in HGG surgery was reviewed according to PRISMA guidelines. Results: 3,756 published studies were screened, 536 evaluated, and 45 included. Of studies that directly compared the use of 5-ALA to white light (28.9%), 5-ALA lead to a better progression-free survival (PFS) and overall survival (OS) in 88.4 and 67.5% of patients, respectively. 42.2% demonstrated that 5-ALA use was associated with less post-op neurological deficits, whereas 23.3% of studies showed that surgeries using 5-ALA lead to more deficits. 34.5% demonstrated no difference between 5-ALA and without. Conclusions: 5-ALA was found to be associated with a greater extent of resection and longer OS and PFS in HGG surgeries. Postop neurologic deficit rates were inconclusive when comparing 5-ALA groups to white light groups. 5-ALA is a useful surgical adjunct for HGG resection with preserved patient safety.

Background: Adult thalamic gliomas (ATGs) present a surgical challenge given their depth and proximity to eloquent brain regions.Though a relative abundance of literature has been published regarding the surgical management of thalamic lesions in pediatric patients, a scarce amount exists dedicated to adult populations. Methods: Literature regarding surgical management of thalamic gliomas in adult patients was reviewed according to the PRISMA guidelines. Fours databases were searched with keywords “‘thalamic glioma’ AND ‘surgical intervention’ OR ‘thalamic glioma’ AND ‘surgical treatment’” in July 2021 for articles assessing surgical techniques of ATG resection. Results: The mean age of adult undergoing surgical management was 33.57 years with a median preoperative KPS of 72.15. Among the 507 cases, several surgical approaches were utilized. Transcortical approaches were most frequently used accounting for 37.8% of all cases followed by transventricular (23.8%), transcallosal (22.8%), and trans-sylvian transinsular (2.92%). Conclusions: Studies in this review agree that decreased age, low grade glioma, increased KPS, and increased duration of symptoms are positive prognostic factors. Greater degree of resection provides a positive survival benefit, and transcortical approaches appear to carry a greater overall survival. Stratified guidelines could pose an overall advantage to surgical success when making decisions on treatment approach.

Background: While managing patients with high-grade gliomas (HGG), predicting recurrence, or differentiating between pseudoprogression (radiation necrosis) and true tumour progression would be invaluable in improving overall prognosis. Characterizing small RNA (sRNA) expression profiles from plasma-derived extracellular vesicles (EVs) over the course of a patient’s treatments, may allow for patient-specific treatment modifications and improve outcomes. Methods: EVs were isolated using Vn96 capture from plasma obtained longitudinally from HGG patients perioperatively and with routine, follow-up surveillance imaging. sRNA was enriched from the EVs, upon which sequencing and unsupervised hierarchal clustering of sRNA signatures were completed. Expression profiles were grouped longitudinally with the clinical status of patients. Results: Cluster analysis of sequences from nine HGG patients, has revealed a sRNA signature that is able to distinguish between tumours showing evidence of progression and those remaining stable over time. Those samples obtained from patients where a clinical diagnosis of tumour progression or pseudoprogression were uncertain, were found to cluster into progression vs. stable signatures. Clinical follow up of these patients will reveal the predictive value of these identified clusters. Conclusions: These preliminary findings demonstrate the potential utility of small RNA profiling of EVs obtained from patients with high-grade gliomas as non-invasive biomarkers for recurrent/progressive disease or stability/pseudoprogression.

Background: Pediatric posterior fossa ependymoma contributes to morbidity and mortality in children. Following gross total resection and adjuvant radiotherapy, there is a known risk of local recurrence that portends a dismal prognosis. We sought to characterize survival in a molecularly defined cohort with an emphasis on recurrence patterns that influence outcome. Methods: This study was approved by the Ethics Board of the Hospital for Sick Children. We performed a twenty-year single-center retrospective study to identify clinical, demographic and treatment characteristics of patients with pathologically diagnosed posterior fossa ependymoma. Results: There were 60 patients identified that underwent primary resection. Recurrence rate in the cohort was 48% with 29 cases of recurrent ependymoma occurring at a mean time of 24 months after index surgery. No mortalities were observed among patients undergoing primary resection without recurrent disease. Median cohort survival was 12.3 years in the primary cohort and and 6.32 years among patients recurrent ependymoma. Recurrent disease was significantly associated with worse overall survival after multivariate analysis (HR = 0.024). Conclusions: We highlight overall survival and factors influencing mortality in pediatric posterior fossa ependymoma. Recurrent disease confers a worse prognosis. We describe for the first time survival trends following local and distant recurrences managed through multiple resections.