Vestibular Schwannoma International Study of Active Surveillance Versus Stereotactic Radiosurgery: The VISAS Study.

PURPOSE: The present study assesses the safety and efficacy of stereotactic radiosurgery (SRS) versus observation for Koos grade 1 and 2 vestibular schwannoma (VS), benign tumors affecting hearing and neurological function. METHODS AND MATERIALS: This multicenter study analyzed data from Koos grade 1 and 2 VS patients managed with SRS (SRS group) or observation (observation group). Propensity score matching balanced patient demographics, tumor volume, and audiometry. Outcomes measured were tumor control, serviceable hearing preservation, and neurological outcomes. RESULTS: In 125 matched patients in each group with a 36-month median follow-up (P = .49), SRS yielded superior 5- and 10-year tumor control rates (99% CI, 97.1%-100%, and 91.9% CI, 79.4%-100%) versus observation (45.8% CI, 36.8%-57.2%, and 22% CI, 13.2%-36.7%; P < .001). Serviceable hearing preservation rates at 5 and 9 years were comparable (SRS 60.4% CI, 49.9%-73%, vs observation 51.4% CI, 41.3%-63.9%, and SRS 27% CI, 14.5%-50.5%, vs observation 30% CI, 17.2%-52.2%; P = .53). SRS were associated with lower odds of tinnitus (OR = 0.39, P = .01), vestibular dysfunction (OR = 0.11, P = .004), and any cranial nerve palsy (OR = 0.36, P = .003), with no change in cranial nerves 5 or 7 (P > .05). Composite endpoints of tumor progression and/or any of the previous outcomes showed significant lower odds associated with SRS compared with observation alone (P < .001). CONCLUSIONS: SRS management in matched cohorts of Koos grade 1 and 2 VS patients demonstrated superior tumor control, comparable hearing preservation rates, and significantly lower odds of experiencing neurological deficits. These findings delineate the safety and efficacy of SRS in the management of this patient population.

The 5-factor modified frailty index as a prognostic factor of stereotactic radiosurgery for metastatic disease to the brain.

OBJECTIVE: Frailty, a state of increased vulnerability to adverse health outcomes, is associated with poor neurosurgical outcomes. The relationship between frailty and stereotactic radiosurgery (SRS) for brain metastases (BMs), however, has not been adequately described. In this study, the authors attempted to examine the connection between frailty and outcomes for patients receiving SRS for BMs. METHODS: A single-center retrospective cohort study was performed. The 5-factor modified frailty index (mFI-5) was used to stratify patients into pre-frail (mFI-5 score 0-1), frail (mFI-5 score 2), and severely frail (mFI-5 score ≥ 3) cohorts at the time of SRS treatment. Both overall survival (OS) and progression-free survival (PFS) were evaluated. Factors associated with OS/PFS were assessed using Kaplan-Meier analysis and a Cox proportional hazards model. RESULTS: Two hundred three patients met the inclusion criteria and received SRS to one or more BMs. Fifty-six patients (27.6%) received SRS as an adjuvant treatment. The 12-month OS and PFS rates were 58.6% and 45.5%, respectively. One hundred twenty-six patients (62.1%) were classified as pre-frail, 58 (28.6%) as frail, and 19 (9.4%) as severely frail. Significantly less OS was demonstrated in frailer groups (frail hazard ratio [HR] 3.14, p < 0.005; severely frail HR 3.13, p < 0.005). Compared with pre-frail patients, frail patients had shorter intervals of PFS (frail HR 2.05, p < 0.005). Five patients (2.5%) had symptomatic radiation necrosis (RN) and 60 (29.6%) required repeat radiation. CONCLUSIONS: Higher frailty scores at the time of SRS treatment were predictive of shorter OS and PFS intervals.

Foraminal stenosis and radiculopathy secondary to tophaceous gout: illustrative case.

BACKGROUND: Tophaceous gout is a severe form of gout that results in the formation of large nodules, or tophi, in the affected joints and surrounding tissues. Gouty tophi in the spine have a constellation of presentations that often mimic other pathologies and may not be easily discernable from more common pathologic processes. OBSERVATIONS: A 47-year-old female with a history of chronic renal disease, obesity, gout, inflammatory polyarthritis, and multiple sclerosis presented with 6 months of low-back pain and lumbar radiculopathy affecting the right lower extremity. A lumbar magnetic resonance imaging study revealed right foraminal stenosis and spondylolisthesis at levels L4-5. An intraspinal extradural mass was noted adjacent to the traversing right L5 and exiting right L4 nerve roots. A bilateral decompressive laminectomy, facetectomy, and foraminotomy of L4-5 was performed. A calcific, chalky-white mass was discovered in the foramen, and pathology determined the specimen to be a gout tophus. Postoperatively, the patient endorsed the resolution of her preoperative symptoms, which have not returned on follow-up. LESSONS: Reports of gouty depositions compressing the spinal cord in the current literature are relatively rare. Although the diagnosis of gouty tophi can only be confirmed histologically, patient history may serve as a helpful diagnostic tool.

Protracted respiratory failure in a case of global spinal syringomyelia and Chiari malformation following administration of diazepam: illustrative case.

BACKGROUND: Syringomyelia is defined as dilation of the spinal cord's central canal and is often precipitated by skull base herniation disorders. Although respiratory failure (RF) can be associated with skull base abnormalities due to brainstem compression, most cases occur in pediatric patients and quickly resolve. The authors report the case of an adult patient with global spinal syringomyelia and Chiari malformation who developed refractory RF after routine administration of diazepam. OBSERVATIONS: A 31-year-old female presented with malnutrition, a 1-month history of right-sided weakness, and normal respiratory dynamics. After administration of diazepam prior to magnetic resonance imaging (MRI), she suddenly developed hypercapnic RF followed MRI and required intubation. MRI disclosed a Chiari malformation type I and syrinx extending from C1 to the conus medullaris. After decompressive surgery, her respiratory function progressively returned to baseline status, although 22 months after initial benzodiazepine administration, the patient continues to require nocturnal ventilation. LESSONS: Administration of central nervous system depressants should be closely monitored in patients with extensive syrinx formation given the potential to exacerbate diminished central respiratory drive. Early identification of syrinx in the context of Chiari malformation and hemiplegia should prompt clinical suspicion of underlying respiratory compromise and early involvement of intensive care consultants.

The Utility of the 5 Factor Modified Frailty Index in Outcome Prediction for Patients with Chronic Subdural Hematoma Treated with Surgical Drainage.

OBJECTIVE: Increasing frailty is a significant determinant of perioperative morbidity and mortality within neurosurgical literature. This study investigates the predictive value of the modified frailty index 5 (mFI-5) for postoperative morbidity and mortality following surgical drainage of chronic subdural hematoma (cSDH). METHODS: A retrospective cohort study was performed on patients who underwent surgical evacuation of a cSDH. The mFI-5 score was calculated for each patient and used to stratify patients: prefrail (mFI-5<2), frail (mFI-5 = 2), and severely frail (mFI-5>2). Multivariate Cox proportional hazards (CPH) regression analysis were used to identify factors associated with our primary outcomes: overall survival and 30-day readmission. Secondary outcomes included nonhome discharge, length of stay, hematoma accumulation, development of new postoperative neurologic deficits, resolution of preoperative neurologic deficits, and a modified Rankin score >2 at discharge. RESULTS: 118 patients with a mean age of 74.4 ± 11.9 years were analyzed. All baseline demographics were similar across the 3 groups. On multivariate analysis, severely frail patients (N = 24, 20.3%) had increased rates of 30-day readmission (hazard ratio [HR] 4.3, CPH regression P value<0.001) and postoperative mortality (HR 3.1, CPH regression P value<0.01) compared to the prefrail cohort. Severely frail patients had increased rates of nonhome disposition (HR 9.6, CPH regression P value< 0.001), development of new postoperative neurologic deficits (HR 2.75, CPH regression P value = 0.03), and hematoma reaccumulation (HR 4.07, CPH regression P value = 0.004). A novel scoring system accounting for patient age and frailty was predictive of 90-day mortality (area under the curve 0.77). CONCLUSIONS: Frailty, measured by the mFI-5, and our novel scoring system hold a predictive value regarding outcomes for patients undergoing surgical drainage of a cSDH.

Paddle Lead Spinal Cord Stimulation in the Morbidly Obese Patient Population: Outcomes and Complications in a Single-Surgeon Cohort.

BACKGROUND: Paddle lead spinal cord stimulation (SCS) is used to treat refractory chronic pain. Morbidly obese patients seek SCS to reduce chronic pain. However, these patients face worse surgical outcomes, and the SCS literature has not evaluated safety and efficacy in this patient population. This study is the largest single-surgeon case series to date on morbidly obese patients with paddle lead SCS implantations. The primary objective is to report postoperative complication rates in morbidly obese patients receiving SCS implants. The secondary objective is to report patient-reported pain scores and Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference and physical function scores in these patients. METHODS: A retrospective chart review was conducted. The patient charts were reviewed from the day of procedure consent to 6 months postop. Demographic information, pain scores, PROMIS scores, neurological complications, infections, and wound complications were documented. RESULTS: Sixty-seven patients were included. The mean preoperative BMI was 44.47 ± 4.02 kg/m2. The mean age was 58.9 ± 11.4 years old. There were no neurological complications. 3/67 (4%) developed culture-positive infections. Nine out of sixty-seven (13%) patients developed superficial wound dehiscence without underlying infection. The mean postop PROMIS physical function score was 31.6 ± 6.2 (n = 16) and the mean post-op PROMIS pain interference score was 64.0 ± 6.4 (n = 16). There was a reduction in pain scores, from 7.9 ± 1.7 preop to 5.7 ± 2.5 postop (n = 22, P = 0.004). CONCLUSIONS: Paddle lead SCS implantation is safe for morbidly obese patients. The only minimal-risk complications present were postoperative infections and wound dehiscence. Surgical care can be modified to further reduce the rates of infection and dehiscence.

Vasospasm secondary to responsive neurostimulator placement: a previously unreported complication. Illustrative case.

BACKGROUND: The Responsive Neurostimulation (RNS) system is an implantable device for patients with drug-resistant epilepsy who are not candidates for resection of a seizure focus. As a relatively new therapeutic, the full spectrum of adverse effects has yet to be determined. A literature review revealed no previous reports of cerebral vasospasm following RNS implantation. OBSERVATIONS: A 35-year-old man developed severe angiographic and clinical vasospasm following bilateral mesial temporal lobe RNS implantation. He initially presented with concerns for status epilepticus 8 days after implantation. On hospital day 3, a decline in his clinical examination prompted imaging studies that revealed a left middle cerebral artery (MCA) stroke with angiographic evidence of severe vasospasm of the left internal carotid artery (ICA), MCA, anterior cerebral artery (ACA), and right ICA and ACA. Despite improvements in angiographic vasospasm after appropriate treatment, a thrombus developed in the posterior M2 branch, requiring mechanical thrombectomy. Ultimately, the patient was stabilized and discharged to a rehabilitation facility with residual cognitive and motor deficits. LESSONS: Cerebral vasospasm as a cause of ischemic stroke after uneventful RNS implantation is exceedingly rare, yet demands particular attention given the potential for severe consequences and the growing number of patients receiving RNS devices.

Spinal cord stimulation: A novel approach to pain management in Dercum's disease.

Background: Dercum's Disease (DD) is a rare chronic pain syndrome in which patients experience extreme burning pain associated with subcutaneous lipomatous tissue deposits. These patients may also present with; weakness, psychiatric symptoms, metabolic derangements, sleep disturbance, impaired memory, and easy bruising. Common risk factors for DD include: obesity, Caucasian race, and female sex. The etiology of DD remains under debate while it has proven highly resistant to treatment (i.e., requiring high doses of opioids for adequate pain management). Case Description: A 48-year-old female with DD and a prior spinal cord stimulator (SCS) placed for chronic back pain, presented with recurrent back pain, and increased falling. Surgery to replace her SCS resulted in improvement in her back pain and a decreased incidence of falls. Furthermore, she noticed significant improvement in the burning pain attributed to her subcutaneous nodules; this most markedly occurred at and below the level of stimulator placement. Conclusion: A 48-year-old female with the extremely rare condition, DD experienced dramatic reduction in her pain following the successful revision of her SCS.

Lumbar pedicle screw pseudoarthrosis salvage technique with moldable, bioabsorbable, calcium phosphate-based putty: illustrative case.

BACKGROUND: Pseudoarthrosis is a complication of spinal fixation. Risk factors include infection, larger constructs, significant medical comorbidities, and diabetes. The authors present a case report of dilated pedicle screw pseudoarthrosis salvaged with moldable, settable calcium phosphate-based putty. OBSERVATIONS: The patient presented with back pain and radiculopathy in the setting of poorly controlled diabetes. He was taken to the operating room for laminectomy and fusion complicated by postoperative infection requiring incision and drainage. He returned to the clinic 6 months later with pseudoarthrosis of the L4 screws and adjacent segment degeneration. He was taken for revision with extension of fusion. The L4 tracts were significantly dilated. A moldable, bioabsorbable polymer-based putty containing calcium phosphate was used to augment the dilated tract after decortication back to bleeding bone, allowing good purchase of screws. The patient did well postoperatively. LESSONS: There are several salvage options for clinically significant pseudoarthrosis after spinal fixation, including anterior or lateral constructs, extension, and revision of fusion. The authors were able to obtain good screw purchase with dilated screw tracts after addition of moldable, bioabsorbable polymer-based putty containing calcium phosphate. It appears that this may represent an effective salvage strategy for dilated pseudoarthropathy in select settings to support extension of fusion.