Recurrent choroid plexus carcinoma treated with CyberKnife radiosurgery: illustrative case.

BACKGROUND: Choroid plexus carcinomas (CPCs) are rare malignant brain tumors primarily affecting children younger than 2 years old. These tumors originate from the choroid plexus epithelium and are a subtype of choroid plexus tumors, which account for 1%-4% of pediatric brain tumors. Although CPCs often show a notably high recurrence rate after surgery, the standard treatment approach remains gross-total resection (GTR) of the tumor, given the lack of clinical data supporting the effectiveness of adjunct treatment options such as radiotherapy or chemotherapy. OBSERVATIONS: A 16-year-old female with a history of a recurrent cranial CPC resistant to surgery and radiotherapy was treated with CyberKnife stereotactic radiosurgery (SRS), following resection. The procedures successfully maintained local disease control for 41 months; however, there was a subsequent recurrence, ultimately leading to the death of the patient. LESSONS: CPC treatment remains challenging. SRS can be used as a viable adjunct to surgery, which remains the gold standard, although it can also be considered for nonsurgical candidates or when GTR cannot be achieved. Nevertheless, it is crucial to conduct additional research to explore diverse approaches for radiosurgery, including its role as the primary treatment modality versus its combination with surgery, radiotherapy, or chemotherapy. https://thejns.org/doi/10.3171/CASE23748.

Primary Stereotactic Body Radiotherapy for Spinal Bone Metastases From Lung Adenocarcinoma.

OBJECTIVE: This study aimed to assess the results of primary stereotactic body radiotherapy (SBRT) for spinal bone metastases (SBM) originating from lung adenocarcinoma (ADC). We considered the revised Tokuhashi score (rTS), Spinal Instability Neoplastic Score (SINS), and genetic characteristics. METHODS: We examined adult patients with lung ADC who underwent primary SBRT (using the CyberKnife System) for SBM between March 2012 and January 2023. RESULTS: We analyzed data from 99 patients, covering 152 SBM across 194 vertebrae. The overall local control (LC) rate was 77.6% for SBM from lung ADC, with a LC rate of 90.7% at 1 year. The median period for local progression (LP) occurrence was recorded at 10.0 (3-52) months. Additionally, Asian patients demonstrated higher LC rates than White patients. Utilizing the rTS and SINS as predictive tools, we revealed that a poor survival prognosis and an unstable spinal structure were associated with increased rates of LP. Furthermore, the presence of osteolytic bone destructions and pain complaints were significantly correlated with the occurrence of LP. In the cohort of this study, 108 SBM underwent analysis to determine the expression levels of programmed cell death ligand 1 (PD-L1). Additionally, within this group, 60 showed mutations in the epidermal growth factor receptor (EGFR) alongside PD-L1 expression. Nevertheless, these genetic differences did not result in statistically significant differences in the LC rate. CONCLUSION: The one-year LC rate for primary SBRT targeting SBM from lung ADC stood at 90.7%, particularly with the use of the CyberKnife System. Patients achieving LC exhibited significantly longer survival times compared to those with LP.

Stereotactic radiosurgery for facial nerve hemangioma: Case report and systematic review.

BACKGROUND: Facial nerve hemangiomas (FNHs) are rare tumors that primarily occur near the geniculate ganglion in the temporal bone. Despite their rarity, they can cause significant facial nerve dysfunction. The optimal management approach for FNHs remains uncertain, with surgery being the mainstay but subject to debate regarding the extent of resection and preservation of the facial nerve. METHODS: Systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We queried the PubMed/Medline (accessed on 5 March 2024) electronic database using combinations of the following search terms and words text: "geniculate ganglion hemangioma", "ganglional hemangioma", "hemangioma of the facial nerve", "facial hemangioma", and "intratemporal hemangioma". RESULTS: We identified a total of 30 literatures (321 patients). The most common site involved for the facial nerve hemangioma was the geniculate ganglion area followed by internal auditory canal, tympanic segment, labyrinthine segment and mastoid involvement. All patients were treated with conservative management or surgery. We report a 48-year-old female patient with HB grade 2 facial palsy and hemifacial spasm underwent SRS using Cyberknife technology. The treatment targeted the FNH in the left internal acoustic canal near the geniculate ganglion. Six months post-treatment, clinical improvement was evident, and lesion control was confirmed in a follow-up brain MRI. CONCLUSION: The rarity of FNHs contributes to the lack of consensus on optimal management. This illustrative case demonstrates the feasibility of SRS as a standalone treatment for FNHs.

Dosimetric Comparison of Dedicated Radiosurgery Platforms for the Treatment of Essential Tremor: Technical Report.

Essential tremor (ET) is one of the most common adult movement disorders. As the worldwide population ages, the incidence and prevalence of ET is increasing. Although most cases can be managed conservatively, there is a subset of ET that is refractory to medical management. By virtue of being "reversible", deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of the thalamus is one commonly accepted intervention. As an alternative to invasive and expensive DBS, there has been a renaissance in treating ET with lesion-based approaches, spearheaded most recently by high-intensity focused ultrasound (HIFU), the hallmark of which is that it is non-invasive. Meanwhile, stereotactic radiosurgical (SRS) lesioning of VIM represents another time-honored lesion-based non-invasive treatment of ET, which is especially well suited for those patients that cannot tolerate open neurosurgery and is now also getting a "second look". While multiple SRS platforms have been and continue to be used to treat ET, there is little in the way of dosimetric comparison between different technologies. In this brief technical report we compare the dosimetric profiles of three major radiosurgical platforms (Gamma Knife, CyberKnife Robotic Radiosurgery, and Zap-X Gyroscopic Radiosurgery (GRS)) for the treatment of ET. In general, the GRS and Gamma Knife were shown to have the best theoretical dosimetric profiles for VIM lesioning. Nevertheless the relevance of such superiority to clinical outcomes requires future patient studies.

Automatic Segmentation of Vestibular Schwannomas: A Systematic Review.

BACKGROUND: Vestibular schwannomas (VSs) are benign tumors often monitored over time, with measurement techniques for assessing growth rates subject to significant interobserver variability. Automatic segmentation of these tumors could provide a more reliable and efficient for tracking their progression, especially given the irregular shape and growth patterns of VS. METHODS: Various studies and segmentation techniques employing different Convolutional Neural Network architectures and models, such as U-Net and convolutional-attention transformer segmentation, were analyzed. Models were evaluated based on their performance across diverse datasets, and challenges, including domain shift and data sharing, were scrutinized. RESULTS: Automatic segmentation methods offer a promising alternative to conventional measurement techniques, offering potential benefits in precision and efficiency. However, these methods are not without challenges, notably the "domain shift" that occurs when models trained on specific datasets underperform when applied to different datasets. Techniques such as domain adaptation, domain generalization, and data diversity were discussed as potential solutions. CONCLUSIONS: Accurate measurement of VS growth is a complex process, with volumetric analysis currently appearing more reliable than linear measurements. Automatic segmentation, despite its challenges, offers a promising avenue for future investigation. Robust well-generalized models could potentially improve the efficiency of tracking tumor growth, thereby augmenting clinical decision-making. Further work needs to be done to develop more robust models, address the domain shift, and enable secure data sharing for wider applicability.

Long-Term (>24 Months) Duration of Symptoms Negatively Impacts Patient-Reported Outcomes Following Anterior Cervical Discectomy and Fusion for Cervical Radiculopathy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate the impact of long symptom duration (>24 mo) on patient self-reported outcomes for pain, function, and quality of life following anterior cervical discectomy and fusion (ACDF) for cervical radiculopathy. SUMMARY OF BACKGROUND DATA: ACDF is an effective treatment to relieve the symptoms of cervical radiculopathy. However, there is no consensus on whether prolonged preoperative length of symptoms negatively impacts postoperative outcomes. METHODS: This study included consecutive patients who underwent ACDF for cervical radiculopathy from May 1, 2012 to Dec 1, 2019 by a single surgeon. Patients were stratified by short (<24 mo) and long (>24 mo) duration of symptoms. Outcomes including visual analog scale (VAS) neck and arm, neck disability index (NDI), EuroQol-5D (EQ-5D), and overall state of health (EQ-VAS) were compared between cohort both for absolute values and percentage of patients achieving minimal clinically important difference. RESULTS: A total of 111 consecutive patients were included in our study, including 59 patients in the short symptom duration group and 52 patients in the long symptom duration group. The mean age of the patients was 51.4±9.4 and 41 (36.9%) were female. The baseline VAS neck and arm, NDI, EQ-5D, and EQ-VAS were similar between groups. Patients in both long and short symptom duration groups had clinical improvement following surgery. However, patients with short symptom duration had better VAS Neck and EQ-5D outcomes, and were more likely to meet minimal clinically important difference for NDI, EQ-5D, or any outcome. Multivariate analysis confirmed symptom duration <24 months as an independent predictor for better patient-reported outcomes. CONCLUSION: We appreciated better clinical outcomes in patients with shorter symptom duration who received ACDF for cervical radiculopathy. On the basis of this data, we advocate for prompt treatment of cervical radiculopathy to avoid the potential for long-term impairment. LEVEL OF EVIDENCE: Level 3.

Bilateral occipital condyle fracture with an avulsion fracture of the foramen magnum: nonoperative care guided by a traction test. Illustrative case.

BACKGROUND: Bilateral occipital condyle fractures (OCFs) with involvement of the inferior clivus, otherwise known as "avulsion of the anterior foramen magnum," are an exceedingly rare injury with only a few published reports. OBSERVATIONS: A 24-year-old male presented with bilateral OCFs with involvement of the clivus after a motor vehicle accident. The patient had no neurological deficits and was successfully managed nonoperatively using a halo vest. The authors used a traction test to guide the duration of nonoperative care. The operative and nonoperative management of this rare injury is discussed with respect to other cases in the literature. LESSONS: External immobilization through a halo vest is an effective treatment option for bilateral OCFs with clivus involvement. The traction test can be used, along with computed tomography, to guide the duration of treatment.

Spinal metastases of pineal region glioblastoma with primitive neuroectodermal features highlighting the importance of molecular diagnoses: illustrative case.

BACKGROUND: Glioblastoma (GBM) is the most common primary brain tumor with poor patient prognosis. Spinal leptomeningeal metastasis has been rarely reported, with long intervals between the initial discovery of the primary tumor in the brain and eventual spine metastasis. OBSERVATIONS: Here, the authors present the case of a 51-year-old male presenting with 7 days of severe headache, nausea, and vomiting. Magnetic resonance imaging of the brain and spine demonstrated a contrast-enhancing mass in the pineal region, along with spinal metastases to T8, T12, and L5. Initial frozen-section diagnosis led to the treatment strategy for medulloblastoma, but further molecular analysis revealed characteristics of isocitrate dehydrogenase-wild type, grade 4 GBM. LESSONS: Glioblastoma has the potential to show metastatic spread at the time of diagnosis. Spinal imaging should be considered in patients with clinical suspicion of leptomeningeal spread. Furthermore, molecular analysis should be confirmed following pathological diagnosis to fine-tune treatment strategies.

Stereotactic Radiosurgery for Contrast-Enhancing Satellite Nodules in Recurrent Glioblastoma: A Rare Case Series From a Single Institution.

Introduction Glioblastoma (GBM) is the most common malignant adult brain tumor and is invariably fatal. The standard treatment for GBM involves resection where possible, followed by chemoradiation per Stupp's protocol. We frequently use stereotactic radiosurgery (SRS) as a single-fraction treatment for small (volume ≤ 1cc) nodular recurrent GBM to the contrast-enhancing target on T1 MRI scan. In this paper, we aimed to evaluate the safety and efficacy of SRS for patients with contrast-enhancing satellite nodules in recurrent GBM. Methods This retrospective study analyzed the clinical and radiological outcomes of five patients who underwent CyberKnife (Accuray Inc., Sunnyvale, California) SRS at the institute between 2013 and 2022. Results From 96 patients receiving SRS for GBM, five (four males, one female; median age 53) had nine distinct new satellite lesions on MRI, separate from their primary tumor beds. Those nine lesions were treated with a median margin dose of 20 Gy in a single fraction. The three-, six, and 12-month local tumor control rates were 77.8%, 66.7%, and 26.7%, respectively. Median progression-free survival (PFS) was seven months, median overall survival following SRS was 10 months, and median overall survival (OS) was 35 months. Interestingly, the only lesion that did not show radiological progression was separate from the T2-fluid attenuated inversion recovery (FLAIR) signal of the main tumor. Conclusion Our SRS treatment outcomes for recurrent GBM satellite lesions are consistent with existing findings. However, in a unique case, a satellite nodule distinct from the primary tumor's T2-FLAIR signal and treated with an enlarged target volume showed promising control until the patient's demise. This observation suggests potential research avenues, given the limited strategies for 'multicentric' GBM lesions.

Subarachnoid Hemorrhage, Delayed Cerebral Ischemia, and Milrinone Use in Canada.

INTRODUCTION: Delayed cerebral ischemia (DCI) is a complication of aneurysmal subarachnoid hemorrhage (aSAH) and is associated with significant morbidity and mortality. There is little high-quality evidence available to guide the management of DCI. The Canadian Neurosurgery Research Collaborative (CNRC) is comprised of resident physicians who are positioned to capture national, multi-site data. The objective of this study was to evaluate practice patterns of Canadian physicians regarding the management of aSAH and DCI. METHODS: We performed a cross-sectional survey of Canadian neurosurgeons, intensivists, and neurologists who manage aSAH. A 19-question electronic survey (Survey Monkey) was developed and validated by the CNRC following a DCI-related literature review (PubMed, Embase). The survey was distributed to members of the Canadian Neurosurgical Society and to Canadian members of the Neurocritical Care Society. Responses were analyzed using quantitative and qualitative methods. RESULTS: The response rate was 129/340 (38%). Agreement among respondents was limited to the need for intensive care unit admission, use of clinical and radiographic monitoring, and prophylaxis for the prevention of DCI. Several inconsistencies were identified. Indications for starting hyperdynamic therapy varied. There was discrepancy in the proportion of patients who felt to require IV milrinone, IA vasodilators, or physical angioplasty for treatment of DCI. Most respondents reported their facility does not utilize a standardized definition for DCI. CONCLUSION: DCI is an important clinical entity for which no homogeneity and standardization exists in management among Canadian practitioners. The CNRC calls for the development of national standards in the definition, identification, and treatment of DCI.

Work-up and Management of Asymptomatic Extracranial Traumatic Vertebral Artery Injury.

BACKGROUND: Non-penetrating head and neck trauma is associated with extracranial traumatic vertebral artery injury (eTVAI) in approximately 1-2% of cases. Most patients are initially asymptomatic but have an increased risk for delayed stroke and mortality. Limited evidence is available to guide the management of asymptomatic eTVAI. As such, we sought to investigate national practice patterns regarding screening, treatment, and follow-up domains. METHODS: A cross-sectional, electronic survey was distributed to members of the Canadian Neurosurgical Society and Canadian Spine Society. We presented two cases of asymptomatic eTVAI, stratified by injury mechanism, fracture type, and angiographic findings. Screening questions were answered prior to presentation of angiographic findings. Survey responses were analyzed using descriptive statistics. RESULTS: One hundred-eight of 232 (46%) participants, representing 20 academic institutions, completed the survey. Case 1: 78% of respondents would screen for eTVAI with computed topography angiography (CTA) (97%), immediately (88%). The majority of respondents (97%) would treat with aspirin (89%) for 3-6 months (46%). Respondents would follow up clinically (89%) or radiographically (75%), every 1-3 months. Case 2: 73% of respondents would screen with CTA (96%), immediately (88%). Most respondents (94%) would treat with aspirin (50%) for 3-6 months (35%). Thirty-six percent of respondents would utilize endovascular therapy. Respondents would follow up clinically (97%) or radiographically (89%), every 1-3 months. CONCLUSION: This survey of Canadian practice patterns highlights consistency in the approach to screening, treatment, and follow-up of asymptomatic eTVAI. These findings are relevant to neurosurgeons, spinal surgeons, stroke neurologists, and neuro-interventionalists.

Use of Antibacterial Envelopes for Prevention of Infection in Neuromodulation Implantable Pulse Generators.

BACKGROUND: Neuromodulation unit placement carries a historic infection rate as high as 12%. Treatment of such requires surgical removal and a long course of systemic antibiotics. Antibiotic-impregnated envelopes have been effective in preventing infection in implantable cardiac devices. At our center, 1 surgeon uses these envelopes with all implanted neuromodulation units. OBJECTIVE: To assess the efficacy of antibacterial envelopes in prevention of infection in neuromodulation device placement. METHODS: We conducted a retrospective cohort study of consecutive implantable pulse generator (IPG) unit implantation with an antibacterial envelope at a single center between October 2014 and December 2019. We collected demographic data, including postoperative infections, reoperations, and complications, associated with the IPGs. This cohort was then compared with a historical cohort of consecutive patients undergoing surgery before envelope usage (October 2007-April 2014). RESULTS: In the pre-envelope cohort of 151 IPGs placed in 116 patients, there were 18 culture-confirmed infections (11.9%). In the antibacterial envelope cohort of 233 IPGs placed in 185 patients, there were 5 culture-confirmed infections (2.1%). The absolute risk reduction of the antibacterial envelope was 9.85% (95% CI 4.3%-15.4%, P < .01). The number needed to treat was 10.1 (95% CI 6.5-23.1, P < .01) envelopes to prevent 1 IPG infection. CONCLUSION: We saw a reduced rate of infections in the antibacterial envelope cohort. Although this is likely multifactorial, our results suggest a benefit of antibacterial envelopes on infection after neuromodulation surgery.

Encrypted smartphone text messaging between spine surgeons may reduce after-hours surgery.

PURPOSE: "After-hours" non-elective spine surgery is associated with increased morbidity. Decision-making may be enhanced by collaborative input from experienced local colleagues. At our center, we implemented routine use of a cross-platform messaging system (CPMS; WhatsApp Inc., Mountain View, California) to facilitate quality care discussions and collaborative surgical decision-making between spine surgeons prior to booking cases with the operating room. Our aim is to determine whether encrypted text messaging for shared decision-making between spine surgeons affects the number or type of after-hours spine procedures. METHODS: We retrospectively compared the number, type and length of after-hours spine surgery over three time periods: (A) June 1, 2016-May 31, 2017 (baseline control); (B) June 1, 2017-May 31, 2018 (implementation of retrospective quality care spine rounds); and (C) June 1, 2018-May 31, 2019 (implementation of CPMS). A qualitative analysis of the CPMS transcripts was also performed to assess the rate of between-surgeon agreement for timing and type of procedure. RESULTS: The mean number of after-hours spine surgeries/month over the three study periods (A, B, C) was 10.83, 9.75 and 7.58 (p = 0.014); length of surgery was 41.82, 33.14 and 25.37 h/month (p = 0.001). Group agreement with the attending spine surgeon plan was 74.3% overall and was highest for the most urgent and least urgent types of indications. CONCLUSIONS: Prospective (i.e., prior to booking surgery) quality care discussion for joint decision-making among spine surgeons using CPMS may reduce both the number and complexity of after-hours procedures.

Epithelial-mesenchymal transition, regulated by ß-catenin and Twist, leads to esophageal wall remodeling in pediatric eosinophilic esophagitis.

Eosinophilic Esophagitis (EoE) is an antigen-triggered inflammatory condition of the esophageal lining characterized by eosinophilic infiltration. EoE is associated with significant remodeling, and although this remodeling is reversed by current treatment regimens, symptoms of EoE and associated remodeling reappear upon cessation of therapies. We hypothesized that structural remodeling of cell-cell adhesion is a key factor in the pathogenesis of EoE and that epithelial to mesenchymal transition (EMT) was a viable molecular process to lead to this remodeling. Endoscopically obtained biopsy samples from 18 EoE and 18 control pediatric patients were evaluated by transmission electron microscopy to measure intercellular spaces (IS) between cells. Biopsy samples from all groups were analyzed for cellular levels of cell-cell adhesion proteins: E-cadherin, zonula occludens associated protein-1 (ZO-1), and N-cadherin. We also analyzed for cellular levels and localization two of transcription factors, Twist1 and ß-catenin, that are associated with promoting EMT. The IS was significantly increased in the EoE group compared to the control. We observed a significant decrease in E-cadherin and ZO-1 levels and a concomitant increase in N-cadherin levels in EoE samples compared to control. Further, while there was no significant change in cellular levels of ß-catenin, we observed an altered localization of the protein from the cell membrane in control tissue to a nuclear/perinuclear localization in EoE. We observed higher levels of the transcription factor Twist1 in the EoE group compared to normal which was localized mainly at the nucleus. Our results suggest that the integrity of normally sealed esophageal epithelia is compromised in the EoE patients compared to control subjects, and this is due to alterations in the expression of cell adhesion molecules at the esophageal epithelium. Our data also suggest that EMT, potentially regulated by transcription factors ß-catenin and Twist1, may be responsible for the molecular alteration which leads to the remodeling of esophageal epithelia in EoE.