At our institution, large resection cavities (LRC) of brain metastases (BRM) are typically treated with reduced dose (RD), single-fraction (SF) frame-based (FB) postoperative stereotactic radiosurgery (PSR). We aimed to determine the impact of this management practice on efficacy and safety outcomes. This retrospective analysis examined 50 consecutive patients whose BRM-associated LRCs (> 10 cm3) were treated with SF FB PSR between October 2000 and October 2021. The prescription dose of < 18 Gy for the large tumor beds was applied in 41 patients, and 18 Gy was administered in nine. The frequencies of local tumor control and radionecrosis were the primary endpoints of the study, and survival was the secondary measure of treatment. The median follow-up was 12 months. Comparative analysis of the applied lower versus higher dose revealed: local tumor control rates of 88

Tumor associated macrophages (TAMs) directly contribute to the dismal prognosis of glioblastoma by preventing anti-tumor immunity and promoting tumor invasion and angiogenesis. Inhibiting TAM infiltration is a potential therapeutic strategy in glioblastoma, with several chemokine antagonists in early clinical development. Hydrogen sulfide, a gasotransmitter that regulates microglial accumulation in a wide range of CNS diseases, may be a novel therapeutic target to prevent TAM recruitment in glioblastoma. In this study, hydrogen sulfide concentrations were directly measured from 14 isocitrate dehydrogenase (IDH)-wildtype glioblastoma surgical samples and compared against overall survival as well as expression of TAM markers and chemokines. Effects of hydrogen sulfide donor therapy on survival and TAM recruitment were also examined in a genetically engineered mouse model of glioblastoma. High hydrogen sulfide concentrations conferred a survival benefit in IDH-wildtype glioblastoma, in association with reduced monocyte-derived TAM density and downregulation of CXCL12. These findings were validated by administering hydrogen sulfide donor SG1002 to an immunocompetent mouse model of glioblastoma, which improved survival, inhibited monocyte infiltration, and downregulated CXCL12. Finally, hydrogen sulfide donor treatment directly reduced CXCL12 expression in glioblastoma cells, diminishing their ability to recruit monocytes in vitro. Taken together, these results demonstrate that hydrogen sulfide signaling prevents monocyte-derived TAM accumulation in glioblastoma by inhibiting chemotaxis.

BACKGROUND Parafalcine subdural hematomas (pSDHs) are a subtype of subdural hematoma (SDH) that occur most frequently in older patients after blunt trauma. The literature primarily describes two clinical courses for patients with pSDH: those who are neurologically intact with stable examinations and imaging and those with focal deficits, with or without hematoma progression. Surgical management is undoubtedly required for the latter group; however, there are no evidence-based guidelines specifically for pSDH. This report describes the cases of two patients with traumatic pSDH with neurological deficits who underwent surgical interventions with two different approaches and advocates for the use of stereotactic navigation to achieve adequate evacuation. OBSERVATIONS In the first case, a 55-year-old male with a parafalcine and convexity SDH underwent a hemicraniectomy, followed by a second surgery for evacuation of the residual pSDH due to a persistent neurological deficit. The second case involved an 84-year-old female with a parafalcine and convexity SDH, who underwent surgical evacuation of the pSDH with the aid of stereotactic navigation. LESSONS Approaching the surgical evacuation of a pSDH as if it were a mass lesion led to the use of intraoperative navigation, which resulted in superior localization and complete evacuation, ultimately improving patient outcomes. https://thejns.org/doi/10.3171/CASE24541

Jugulotympanic paraganglioma (JTPG), a benign slow-growing neoplasm in the skull base with a tendency to be locally invasive, poses a treatment challenge because of its proximity to nearby neurovascular structures. The authors describe 11 patents with 12 Fisch-classified JTPGs treated with GammaKnife radiosurgery (GKRS) during a 12-year period. The observed rates of subjective improvement and tumor control were 80% and 83%, respectively. Among the individuals living longer than 5 years, tumor growth developed at 77 and 180 months after radiosurgery in two patients. Treatment-related toxicity or radiation oncogenesis was not observed. GKRS seems to be a valid treatment option for all Fisch designated skull base glomus tumors. Life-long follow-up of these patients is necessary.

Background: Characterization of potential beneficiaries from repeat radiosurgery (RRS) for progressive previously treated brain metastases (PPT-BRM) has not received much attention, perhaps because many patients with BRM die following salvage radiosurgery. These individuals remain at risk for neurological deterioration when BRMs are left untreated. Methods: We attempted to study the advantaged people from our four patients and 531 patients identified in a literature search who were treated with RRS for PPT-BRMs. Results: The 2% incidence rate of PPT-BRM from our institution was lower than rates in previous reports (range, 4–25%). The overall efficacy and minimal morbidty associated with RRS have consistently been demonstrated. Even though RRS for PPT-BRM is believed to be essential in patients with good functional status, descriptions of people who benefitted from RRS are poorly documented. Conclusions: RRS for PPT-BRM, generally efficacious, is associated with a low toxicity profile. It is vital that there is careful patient selection for RRS of PPT-BRM given the overall dismal outlook and the potential serious effect of neglected beneficial treatment as well as the intervention-related radionecrosis on the quality of remaining life. Based on the available evidence, we advocate the continued but cautious use of salvage RRS in these people. More research is needed about the patients gaining benefit from the re-irradiation.

Traumatic subarachnoid-pleural fistula is an uncommon occurrence. We present a case of a patient sustaining a subarachnoid-pleural fistula after a gunshot wound to the neck, which ultimately resulted in substantial pneumocephalus. The patient underwent successful operative repair of the fistula with notable improvement and resolution of pneumocephalus.

OBJECTIVE The use of allograft cellular bone matrices (ACBMs) in spinal fusion has expanded rapidly over the last decade. Despite little objective data on its effectiveness, ACBM use has replaced the use of traditional autograft techniques, namely iliac crest bone graft (ICBG), in many centers. METHODS In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was conducted of the PubMed, Cochrane Library, Scopus, and Web of Science databases of English-language articles over the time period from January 2001 to December 2020 to objectively assess the effectiveness of ACBMs, with an emphasis on the level of industry involvement in the current body of literature. RESULTS Limited animal studies (n = 5) demonstrate the efficacy of ACBMs in spinal fusion, with either equivalent or increased rates of fusion compared to autograft. Clinical human studies utilizing ACBMs as bone graft expanders or bone graft substitutes (n = 5 for the cervical spine and n = 8 for the lumbar spine) demonstrate the safety of ACBMs in spinal fusion, but fail to provide conclusive level I, II, or III evidence for its efficacy. Additionally, human studies are plagued with several limiting factors, such as small sample size, lack of prospective design, lack of randomization, absence of standardized assessment of fusion, and presence of industry support/relevant conflict of interest. CONCLUSIONS There exist very few objective, unbiased human clinical studies demonstrating ACBM effectiveness or superiority in spinal fusion. Impartial, well-designed prospective studies are needed to offer evidence-based best practices to patients in this domain.

Abstract Clinical outcomes were reviewed in 30 patients treated by gamma knife radiosurgery for skull base meningiomas with carotid artery encasement (SKBM‐CAE). The overall clinical improvement rate after treatment was 46%. At a median imaging follow‐up of 49 months, tumor volumes were unchanged, were larger, and were smaller or had resolved in 70%, 23%, and 7% of cases, respectively. The crude survival rate at 10 years was 20% and the complication (new cranial nerve deficit not accompanied by imaging‐shown tumor growth) rate was 10%. SKBM‐CAE is amenable to being effectively and safely controlled with the application of gamma knife radiosurgery.

Traumatic atlantoaxial dislocation without associated odontoid fracture or neurologic deficit is rare. We present the case of a 39-year-old male pedestrian who was struck by a vehicle and sustained a traumatic grade 4 C1-2 retrolisthesis. Closed reduction was successful, and the patient underwent posterior occipitocervical fusion. His neurologic status was good throughout the hospital stay, and he was discharged to a rehabilitation facility with full strength.

There is an ever-increasing number of opioid users among chronic pain patients and safely managing them can be challenging for surgeons, anesthesiologists, pain experts, and addiction specialists. Healthcare providers must be familiar with phenomena typical of opioid users and abusers, including tolerance, physical dependence, hyperalgesia, and addiction. Insufficient pain management is very common in these patients. Patient-centered preoperative communication is integral to setting realistic expectations for postoperative pain, developing successful nonopioid analgesic regimens, minimizing opioid consumption during the postoperative period, and decreasing the number of opioid pills at the risk of diversion. Preoperative evaluation should identify comorbidities and identify risk factors for substance abuse and withdrawal. Intraoperative and postoperative strategies can ensure safe and effective pain management and minimize the potential for morbidity and mortality in this high-risk patient population.

Adolescent idiopathic scoliosis (AIS) is the most common form of pediatric scoliosis. It occurs in individuals between the ages of 10 to 18. By definition, idiopathic scoliosis implies that the etiology is unknown or not related to a specific syndromic, congenital, or neuromuscular condition. Treatment options include conservative management, bracing, or operative intervention.