Application of nonpenetrating titanium clips for primary spinal dural closure following intradural tethered cord release in pediatric tethered cord syndrome: Profile of safety, efficacy, efficiency, and complications.

Introduction: Surgical treatment for tethered cord syndrome (TCS) involves a laminotomy for intradural lysis of filum terminale (LFT), with the goal of releasing excess tension on the conus medullaris by dividing the filum terminale. While LFT alleviates clinical symptoms, it is associated with risks and complications, including cerebrospinal fluid (CSF) leak and infection, either superficial or deep. Some risks and complications of LFT relate to efficiency and quality of primary dural closure and its downstream effects. We sought to assess the utility of nonpenetrating titanium clips (TC) for primary dural closure with a particular focus on operative duration, associated costs, and complication profiles in a series of pediatric patients undergoing LFT, hypothesizing that TC utilization leads to more efficient closure and therefore potentially lower costs and potentially associated anesthetic length and risks. Methods: A 4-surgeon, single institution series of 28 pediatric patients underwent LFT with subsequent dural closure performed with either the AnastoClip® nonpenetrating titanium clips or traditional suture technique between July 2022 and May 2023. In order to compare the safety, efficacy, and cost-effectiveness between the two dural closure techniques, relevant data were collected including patient demographics and rates of CSF leak, infection at three-month follow-up, and reoperation. Operative durations and times from beginning to end of dural closure were recorded. Results: A total of 28 pediatric patients (mean age: 5.9 years, 43% female, range: 0.71-17 years) with TCS underwent LFT. All patients underwent procedures involving intradural surgery of the lumbar region. Dural closure was performed using traditional suturing in 19 patients (67.9%) and TC in 9 (32.1%). With respect to duration of dural closure, the average time to closure using traditional suturing techniques was 1271 s (or 21 min and 11 s), while the average time for TC was 265 s (or 4 min and 25 s). At three-month follow-up, one case of cerebrospinal fluid (CSF) leak or infection was observed in the suture cohort and required reoperation. Conclusion: Clinical outcomes in the TC group were excellent, consistent with previous reports; our findings further suggest that TCs result in more efficient dural closure than traditional suturing techniques. Our findings suggest that TC may be a safe, efficacious, and more efficient alternative to traditional suture for achieving dural closure in pediatric patients with TCS undergoing LFT surgery.

On-Call Workload Differences in Neurosurgery: Resident Call "Weather" and a Departure from Colored Cloud Labels.

BACKGROUND AND OBJECTIVES: Labeling residents as "black" or "white" clouds based on perceived or presumed workloads is a timeworn custom across medical training and practice. Previous studies examining whether such perceptions align with objective workload patterns have offered conflicting results. We assessed whether such peer-assigned labels were associated with between-resident differences in objective, on-call workload metrics in three classes of neurosurgery junior residents. In doing so, we introduce more inclusive terminology for perceived differences in workload metrics. METHODS: Residents were instructed to complete surveys to identify "sunny", "neutral", and "stormy" residents, reflecting least to greatest perceived workloads, of their respective classes. We retrospectively reviewed department and electronic medical records to record volume of on-call work over the first 4 months of each resident's 2nd postgraduate academic year. Inter-rater agreement of survey responses was measured using Fleiss' kappa. All statistical analyses were performed with a significance threshold of P < .05. RESULTS: Across all classes, there was strong inter-rater agreement in the identification of stormy and sunny residents (Kappa = 1.000, P = .003). While differences in on-call workload measures existed within each class, "weather" designations did not consistently reflect these differences. There were significant intraclass differences in per shift consult volume in two classes ( P = .035 and P = .009); however, consult volume corresponded to a resident's weather designations in only one class. Stormy residents generally saw more emergencies and, in 2 classes, performed more bedside procedures than their peers. CONCLUSION: Significant differences in objective on-call experience exist between junior neurosurgery residents. Self- and peer-assigned weather labels did not consistently align with a pattern of these differences, suggesting that other factors contribute to such labels.

Low-Cost Wound Healing Protocol Reduces Infection and Reoperation Rates After Cranioplasty: A Retrospective Cohort Study.

BACKGROUND AND OBJECTIVES: Cranioplasty infections are a common and expensive problem associated with significant morbidity. Our objective was to determine whether a wound healing protocol after cranioplasty reduced the rate of infections and to determine the value of this intervention. METHODS: This is a single-institution retrospective chart review of 2 cohorts of cranioplasty patients over 12 years. The wound healing protocol, consisting of vitamin and mineral supplementation, fluid supplementation, and oxygen support, was instituted for all patients aged older than 15 years undergoing cranioplasty. We retrospectively reviewed the charts of all patients over the study period and compared outcomes before and after protocol institution. Outcomes included surgical site infection, return to operating room within 30 days, and cranioplasty explant. Cost data were collected from the electronic medical record. We included 291 cranioplasties performed before the wound healing protocol and 68 postprotocol. RESULTS: Baseline demographics and comorbidities were comparable between preprotocol and postprotocol groups. Odds of takeback to operating room within 30 days were the same before and after the wound healing protocol (odds ratio [OR] 2.21 [95% CI 0.76-6.47], P = .145). Odds of clinical concern for surgical site infection were significantly higher in the preprotocol group (OR 5.21 [95% CI 1.22-22.17], P = .025). Risk of washout was higher in the preprotocol group (HR 2.86 [95% CI 1.08-7.58], P = .035). Probability of cranioplasty flap explant was also significantly higher in the preprotocol group (OR 4.70 [95% CI 1.10-20.05], P = .036). The number needed to treat to prevent 1 cranioplasty infection was 24. CONCLUSION: A low-cost wound healing protocol was associated with reduced rate of infections after cranioplasty with concomitant reduction in reoperations for washout, saving the health care system more than $50,000 per 24 patients. Prospective study is warranted.

Utilization of Vertebroplasty/Kyphoplasty in the Management of Compression Fractures: National Trends and Predictors of Vertebroplasty/Kyphoplasty.

OBJECTIVE: The purpose of this study is to examine the utilization of kyphoplasty/vertebroplasty procedures in the management of compression fractures. With the growing elderly population and the associated increase in rates of osteoporosis, vertebral compression fractures have become a daily encounter for spine surgeons. However, there remains a lack of consensus on the optimal management of this patient population. METHODS: A retrospective analysis of 91 million longitudinally followed patients from 2016 to 2019 was performed using the PearlDiver Patient Claims Database. Patients with compression fractures were identified using International Classification of Disease, 10th Revision codes, and a subset of patients who received kyphoplasty/vertebroplasty were identified using Common Procedural Terminology codes. Baseline demographic and clinical data between groups were acquired. Multivariable regression analysis was performed to determine predictors of receiving kyphoplasty/vertebroplasty. RESULTS: A total of 348,457 patients with compression fractures were identified with 9.2% of patients receiving kyphoplasty/vertebroplasty as their initial treatment. Of these patients, 43.5% underwent additional kyphoplasty/vertebroplasty 30 days after initial intervention. Patients receiving kyphoplasty/vertebroplasty were significantly older (72.2 vs. 67.9, p < 0.05), female, obese, had active smoking status and had higher Elixhauser Comorbidity Index scores. Multivariable analysis demonstrated that female sex, smoking status, and obesity were the 3 strongest predictors of receiving kyphoplasty/vertebroplasty (odds ratio, 1.27, 1.24, and 1.14, respectively). The annual rate of kyphoplasty/vertebroplasty did not change significantly (range, 8%-11%). CONCLUSION: The majority of vertebral compression fractures are managed nonoperatively. However, certain patient factors such as smoking status, obesity, female sex, older age, osteoporosis, and greater comorbidities are predictors of undergoing kyphoplasty/vertebroplasty.

A technical note on anterolateral mobilization in vertebrobasilar dolichoectasia for relief of brainstem compression.

Vascular compression of neural tissue causing neurological symptoms is a wellknown phenomenon. This is commonly seen in trigeminal neuralgia and, less commonly, in hemifacial spasm by small arteries, which can be treated by microvascular decompression. Rarely, larger arteries, such as the vertebral arteries, may compress the brainstem. This can lead to symptoms of pontine or medullary distress like hemiparesis, dysphagia, or respiratory distress. This is treated by macrovascular decompression. Due to the rare and heterogenous nature of this disease, there is no standardized approach. We describe a novel technique whereby the vertebrobasilar system is mobilized anterolaterally towards the occipital condyle with a sling to decompress the brainstem.
We report two cases of vertebrobasilar dolichoectasia causing brainstem compression. A carotid patch graft sling with anterolateral mobilization to the occipital condyle is described as a surgical nuance to macrovascular decompressive surgery. Briefly, the vertebral artery was identified and dissected away from the brainstem and the bulbar cranial nerves. Bovine pericardium graft was used to create a sling around the artery by suturing the two ends together. The sling was then fixed either to the occipital condyle using cranial plating screws or suturing to the dura of the occipital condyle.
A novel surgical technique for management of vertebrobasilar dolichoectasia causing brainstem compression with progressive neurological deterioration is reported. Anatomical location and the offending vessel should guide neurosurgeons to select the best surgical option to achieve complete decompression of the involved neural structures.

Operative Technique: Angiomatoid Fibrous Histiocytoma-Unique Case and Management.

Objective We describe the first jugular foramen angiomatoid fibrous histiocytoma (AFH) case and the first treatment with preoperative endovascular embolization. AFH is a rare intracranial neoplasm, primarily found in pediatric patient extremities. With an increase in AFH awareness and a well-described genetic profile, intracranial prevalence has also subsequently increased. Study Design We compare this case to previously reported cases using PubMed/Medline literature search, which was performed using the algorithm ["intracranial" AND "angiomatoid fibrous histiocytoma"] through December 2020 (23 manuscripts with 46 unique cases). Patient An 8-year-old female presented with failure to thrive and right-sided hearing loss. Work-up revealed an absence of right-sided serviceable hearing and a large jugular foramen mass. Angiogram revealed primary arterial supply from the posterior branch of the ascending pharyngeal artery, which was preoperatively embolized. Intervention Gross total resection was performed via a translabyrinthine approach. Conclusion The case presented is unique; the first reported AFH at the jugular foramen and the first reported case utilizing preoperative embolization. Preoperative embolization is a relatively safe technique that can improve the surgeon's ability to perform a maximally safe resection, which may decrease the need for adjuvant radiation in rare skull base tumors in young patients.

Effects of 24-hour versus night-float call schedules on the clinical and operative experiences of postgraduate year 2 and 3 neurosurgical residents.

OBJECTIVE: To comply with the removal of the 88-hour week exemption and to support additional operative experience during junior residency, Oregon Health & Science University (OHSU) switched from a night-float call schedule to a modified 24-hour call schedule on July 1, 2019. This study compared the volumes of clinical, procedural, and operative cases experienced by postgraduate year 2 (PGY-2) and PGY-3 residents under these systems. METHODS: The authors retrospectively studied billing and related clinical records, call schedules, and Accreditation Council for Graduate Medical Education case logs for PGY-2 and PGY-3 residents at OHSU, a tertiary academic health center, for the first 4 months of the academic years from 2017 to 2020. The authors analyzed the volumes of new patient consultations, bedside procedures, and operative procedures performed by each PGY-2 and PGY-3 resident during these years, comparing the volumes experienced under each call system. RESULTS: Changing from a PGY-2 resident-focused night-float call system to a 24-hour call system that was more evenly distributed between PGY-2 and PGY-3 residents resulted in decreased volume of new patient consultations, increased volume of operative procedures, and no change in volume of bedside procedures for PGY-2 residents. PGY-3 residents experienced a decrease in operative procedure volume under the 24-hour call system. CONCLUSIONS: Transition from a night-float system to a 24-hour call system altered the distribution of clinical and procedural experiences between PGY-2 and PGY-3 residents. Further research is necessary to understand the impact of these changes on educational outcomes, quality and safety of patient care, and resident satisfaction.

Lumbar Pneumorrhachis Associated With Basilar Skull Fractures.

Lumbar pneumorrhachis following head injury is rare and commonly asymptomatic but can be indicative of skull fracture and cerebrospinal fluid (CSF) leak, which may warrant intervention. A PubMed review of the literature was performed using a keyword search to identify cases examining lumbar pneumorrhachis following head injury. Our case series included two patients who had lumbar pneumorrhachis between September 2019 and May 2020 at our center. The literature review summarizes 16 patients from 14 prior reports of pneumorrhachis. In our two-patient case series, neither patient required direct intervention for either pneumorrhachis or CSF leak. Pneumorrhachis is rare following an isolated head injury and is associated with basilar skull fractures and CSF leak. Pneumorrhachis should alert clinicians to the possibility of a CSF leak, which may require intervention.

Acute nontraumatic subdural hematoma from ruptured accessory meningeal artery pseudoaneurysm.

BACKGROUND: Cerebral angiography including internal and external carotid artery injections is crucial in young patients with a spontaneous subdural hematoma. CASE DESCRIPTION: We present the first reported case of an accessory meningeal artery aneurysm in a 46-year-old male with a history of hypertension that led to a spontaneous nontraumatic acute subdural hematoma. A PubMed review of the literature was performed using a keyword search to identify cases examining nontraumatic spontaneous intracranial hematomas related to meningeal artery aneurysms. The literature review summarizes all published reports of middle meningeal artery aneurysms resulting in nontraumatic acute intracranial bleeds. The patient underwent successful coiling of the accessory meningeal artery. CONCLUSION: We propose endovascular treatment for accessory meningeal artery aneurysms and emphasize the utility of angiography of internal and external carotid arteries in a patient with an unexplained intracranial hematoma.

Cerebrospinal Fluid Hypovolemia: A Case Report of a Red Herring.

Mild intracranial hypotension can lead to classically recognizable symptoms such as positional headaches, nausea, vomiting, and occasionally blurred vision. Less commonly, severe cerebrospinal fluid (CSF) hypovolemia can lead to a life-threatening condition that mimics intracranial hypertension, including transtentorial herniation and subsequent rapid neurologic decline. In this report we present a unique case of severe intracranial hypotension from a thoracic tumor resection that led to symptoms initially mistaken for intracranial hypertension, however ultimately correctly diagnosed as severe CSF hypovolemia that improved with dural repair. Additionally, we describe a rare angiography finding associated with CSF hypovolemia, kinking of the basilar artery. Here we report a 47-year-old female with neurofibromatosis Type 2 found to have a T3 intradural extramedullary tumor. She initially presented with urinary incontinence and gait/balance difficulty. She underwent thoracic laminectomies at T3 and T4 for the excision of the lesion. She was discharged on postoperative day 4. On postoperative day 9, she was noted to have nausea, vomiting, and decreased consciousness. Head computed tomography (CT) demonstrated acute downward herniation. She was transferred to our institution from a community facility obtunded and was intubated for airway protection. She was placed in the Trendelenburg position with immediate improvement, and declined every time her head was raised. Angiogram showed significant kinking of her basilar artery. A CT myelogram revealed a CSF leak from her recent thoracic surgery. She underwent exploration of her thoracic wound, and a ventral durotomy was repaired. Following this, she began to tolerate the head of bed elevations and recovered back to her neurologic baseline. A postoperative head CT angiography obtained before discharge showed improvement of her basilar kink. Mild intracranial hypotension is a common finding in patients who undergo procedures that enter the CSF space. Severe intracranial hypotension can easily be missed diagnosed as the signs on the exam are similar to patients with signs of intracranial hypertension. It is of paramount importance that the clinician recognizes brain sag, as the treatment algorithms are vastly different from that of intracranial hypertension leading to transtentorial herniation.

Arteriovenous Malformation Presenting as Symptomatic, Enlarging and Contrast-Enhancing Mass 12 Years After Being Treated with Embolization and Radiotherapy.

BACKGROUND: Gross total resection of arteriovenous malformations (AVMs) of the central nervous system confirmed by formal angiography is accepted as a cure for patients. In some cases, this may not be possible. Even though in these cases other treatment modalities such as endovascular embolization and radiotherapy can be used, long-term follow-up is lacking in the literature. CASE DESCRIPTION: Here we report a case of a 57-year-old woman with history of a right-sided parieto-occipital/periatrial AVM, initially treated with a combination of endovascular embolization and radiotherapy. CONCLUSIONS: The patient subsequently presented (12 years later) with a symptomatic, enlarging, contrast-enhancing mass at the same location that was angiographically occult but ultimately proven to be an AVM on a background of reactive changes on pathology.

Biomarkers of Pineal Region Tumors: A Review.

Background: The pineal gland, a small, pinecone-shaped organ deep within the brain, is responsible for producing melatonin. The gland consists of pineal parenchymal cells and glial cells that can form neoplasms. Pineal region neoplasms can also arise from germ cells and adjacent structures. This review focuses on detection of serum and cerebrospinal fluid (CSF) biomarkers of germ cell tumors and pineal parenchymal cell tumors, as these types comprise most neoplasms specific to the pineal region. Methods: For this review, we searched PubMed using the following keywords: biomarkers, germ cell tumor, germinoma, melatonin, pineal, pineal gland, pineal neoplasm, pinealoma, pineal parenchymal cell tumor, pineal region, and pineal tumor. We limited our search to full-text English articles and identified other relevant sources from the reference lists of identified articles. Results: Serum and CSF biomarker assays have a role in cases of suspected pineal germ cell or parenchymal neoplasms. Biomarkers including alpha-fetoprotein, beta-human chorionic gonadotropin, and placental alkaline phosphatase inform diagnosis and treatment and are important for monitoring germ cell tumor response to treatment. No biomarkers are currently available that inform diagnosis or treatment of pineal parenchymal tumors, although melatonin assays may have a role in monitoring response to treatment. Conclusion: Serum and CSF biomarkers in conjunction with clinical and radiographic evidence of a pineal region mass can inform the decision whether to undertake stereotactic biopsy or surgical excision or whether to proceed straight to medical treatment.

Advances in Neuro-Oncology Imaging Techniques.

BACKGROUND: Central nervous system (CNS) tumors are a rare but devastating malignancy, often robbing patients of the basic quality of life. Despite advances in our understanding of the CNS tumor disease processes, the prognosis for patients with CNS tumors remains poor. Better characterization and diagnostic and monitoring approaches are necessary to assist in diagnosis and treatment of CNS tumors. One important tool in the neuro-oncology armamentarium is the use of advanced imaging techniques. METHODS: We searched PubMed using the keywords neuro-oncology imaging, pseudoprogression, molecular imaging, and biomarkers. We limited our search to full-text English articles and identified other relevant articles from the reference lists of previously identified articles. RESULTS: Advances in imaging techniques have allowed investigators to explore various imaging modalities, from tumor characterization to differentiating pseudoprogression from tumor progression. Better imaging can result in better diagnostic approaches, greater and safer resection techniques, and improved monitoring of tumor progression. CONCLUSION: This review highlights advances in neuro-oncology imaging techniques and their clinical utility in the treatment and management of primary brain tumors.

Lymphocytes influence intracranial aneurysm formation and rupture: role of extracellular matrix remodeling and phenotypic modulation of vascular smooth muscle cells.

BACKGROUND: Intracranial aneurysms (IA) are increasingly recognized as a disease driven by chronic inflammation. Recent research has identified key mediators and processes underlying IA pathogenesis, but mechanistic understanding remains incomplete. Lymphocytic infiltrates have been demonstrated in patient IA tissue specimens and have also been shown to play an important role in abdominal aortic aneurysms (AAA) and related diseases such as atherosclerosis. However, no study has systematically examined the contribution of lymphocytes in a model of IA. METHODS: Lymphocyte-deficient (Rag1) and wild-type (WT; C57BL/6 strain) mice were subjected to a robust IA induction protocol. Rates of IA formation and rupture were measured, and cerebral artery tissue was collected and utilized for histology and gene expression analysis. RESULTS: At 2 weeks, the Rag1 group had significantly fewer IA formations and ruptures than the WT group. Histological analysis of unruptured IA tissue showed robust B and T lymphocyte infiltration in the WT group, while there were no differences in macrophage infiltration, IA diameter, and wall thickness. Significant differences in interleukin-6 (IL-6), matrix metalloproteinases 2 (MMP2) and 9 (MMP9), and smooth muscle myosin heavy chain (MHC) were observed between the groups. CONCLUSIONS: Lymphocytes are key contributors to IA pathogenesis and provide a novel target for the prevention of IA progression and rupture in patients.

Anatomical and functional evidence for trace amines as unique modulators of locomotor function in the mammalian spinal cord.

The trace amines (TAs), tryptamine, tyramine, and ß-phenylethylamine, are synthesized from precursor amino acids via aromatic-L-amino acid decarboxylase (AADC). We explored their role in the neuromodulation of neonatal rat spinal cord motor circuits. We first showed that the spinal cord contains the substrates for TA biosynthesis (AADC) and for receptor-mediated actions via trace amine-associated receptors (TAARs) 1 and 4. We next examined the actions of the TAs on motor activity using the in vitro isolated neonatal rat spinal cord. Tyramine and tryptamine most consistently increased motor activity with prominent direct actions on motoneurons. In the presence of N-methyl-D-aspartate, all applied TAs supported expression of a locomotor-like activity (LLA) that was indistinguishable from that ordinarily observed with serotonin, suggesting that the TAs act on common central pattern generating neurons. The TAs also generated distinctive complex rhythms characterized by episodic bouts of LLA. TA actions on locomotor circuits did not require interaction with descending monoaminergic projections since evoked LLA was maintained following block of all Na(+)-dependent monoamine transporters or the vesicular monoamine transporter. Instead, TA (tryptamine and tyramine) actions depended on intracellular uptake via pentamidine-sensitive Na(+)-independent membrane transporters. Requirement for intracellular transport is consistent with the TAs having much slower LLA onset than serotonin and for activation of intracellular TAARs. To test for endogenous actions following biosynthesis, we increased intracellular amino acid levels with cycloheximide. LLA emerged and included distinctive TA-like episodic bouts. In summary, we provided anatomical and functional evidence of the TAs as an intrinsic spinal monoaminergic modulatory system capable of promoting recruitment of locomotor circuits independent of the descending monoamines. These actions support their known sympathomimetic function.