Increased TMEM166 Level in Patients with Postoperative Stroke after Carotid Endarterectomy.

Postoperative stroke is a challenging and potentially devastating complication after elective carotid endarterectomy (CEA). We previously demonstrated that transmembrane protein 166 (TMEM166) levels were directly related to neuronal damage after cerebral ischemia-reperfusion injury in rats. In this subsequent clinical study, we aimed to evaluate the prognostic value of TMEM166 in patients suffering from post-CEA strokes. Thirty-five patients undergoing uncomplicated elective CEA and 8 patients who suffered ischemic strokes after CEA were recruited. We evaluated the protein level and expression of TMEM166 in patients diagnosed with postoperative strokes and compared it to those in patients who underwent uncomplicated elective CEA. Blood samples and carotid artery plaques were collected and analyzed. High expressions of TMEM166 were detected by immunofluorescence staining and Western Blot in carotid artery plaques of all patients who underwent CEA. Furthermore, circulating TMEM166 concentrations were statistically higher in post-CEA stroke patients than in patients allocated to the control group. Mean plasma concentrations of inflammatory markers, including interleukin 6 (IL-6) and C-reactive protein (CRP), were also elevated in patients with postoperative strokes. Therefore, based on these findings, we hypothesize that elevated TMEM166 levels, accompanied by a strong inflammatory response, serve as a useful biomarker for risk assessment of postoperative stroke following CEA.

C1–C2 intraarticular distraction with anterior cervical cages for basilar invagination realignment: Operative technique nuances and review of literature

Neurosurgical management of basilar invagination (BI) has traditionally been aimed at direct cervicomedullary decompression through transoral dens resection or suboccipital decompression with supplemental instrumented fixation. Dr. Goel introduced chronic atlantoaxial dislocation (AAD) as the etiology in most cases of BI and described a technique for distracting the C1–C2 joint with interfacet spacers to achieve reduction and anatomic realignment. We present our modification to Goel’s surgical technique, in which we utilize anterior cervical discectomy (ACD) cages as C1–C2 interfacet implants. A young adult male presented to our institution with BI, cervicomedullary compression, occipitalization of C1, and Chiari 1 malformation. There was AAD of C1 over the C2 lateral masses. This reduced some with preoperative traction. He underwent successful C1–C2 interfacet joint reduction and arthrodesis with anterior cervical discectomy (ACD) cages and concomittant occiput to C2 instrumented fusion. BI can be effectively treated through reduction of AAD and by utilizing ACD cages as interfacet spacers. (AU)

El tratamiento neuroquirúrgico tradicional para la impresión basilar es principalmente a través de un abordaje trans-oral para la resección del proceso odontoide, seguido de una descompresión suboccipital con instrumentación posterior cervical. Dr. Goel presenta la dislocación atlanto-axial (AA) como una de las etiologías principales en los casos de impresión basilar. A su vez, describió la técnica quirúrgica que incluye la distracción de la articulación AA con cajas para fusión permitiendo la reducción y reajuste anatómico cervical. En este artículo presentamos una variación a la técnica quirúrgica del Dr. Goel en el cual utilizamos implantes utilizados en la discectomía y fusión cervical anterior (DFCA) para la articulación facetaria de C1–C2. Presentamos un paciente adulto masculino que evaluamos en nuestra institución con impresión basilar, compresión cérvico-medular, fusión occipital con el atlas y malformación de Chiari tipo 1. En adición, el paciente tenía evidencia radiográfica de dislocación AA. Se logro obtener reducción mínima de la impresión basilar con tracción cervical pre-operatoria. Luego, se sometió al tratamiento quirúrgico que consistió en el uso de implantes cervicales para la reducción y fusión de la articulación facetaria de C1–C2 complementado por instrumentación y fusión craneocervical. Esta técnica presentada sugiere que la reducción y reajuste anatómico cervical de la dislocación AA con implantes utilizados para DFCA puede ser efectivo para el tratamiento de impresión basilar. (AU)

C1-C2 intraarticular distraction with anterior cervical cages for basilar invagination realignment: Operative technique nuances and review of literature.

Neurosurgical management of basilar invagination (BI) has traditionally been aimed at direct cervicomedullary decompression through transoral dens resection or suboccipital decompression with supplemental instrumented fixation. Dr. Goel introduced chronic atlantoaxial dislocation (AAD) as the etiology in most cases of BI and described a technique for distracting the C1-C2 joint with interfacet spacers to achieve reduction and anatomic realignment. We present our modification to Goel's surgical technique, in which we utilize anterior cervical discectomy (ACD) cages as C1-C2 interfacet implants. A young adult male presented to our institution with BI, cervicomedullary compression, occipitalization of C1, and Chiari 1 malformation. There was AAD of C1 over the C2 lateral masses. This reduced some with preoperative traction. He underwent successful C1-C2 interfacet joint reduction and arthrodesis with anterior cervical discectomy (ACD) cages and concomittant occiput to C2 instrumented fusion. BI can be effectively treated through reduction of AAD and by utilizing ACD cages as interfacet spacers.

Microglia Autophagy Mediated by TMEM166 Promotes Ischemic Stroke Secondary to Carotid Artery Stenosis.

Ischemic stroke can be a serious complication of selective carotid endarterectomy (CEA) in patients with carotid artery stenosis (CAS). The underlying risk factors and mechanisms of these postoperative strokes are not completely understood. Our previous study showed that TMEM166-induced neuronal autophagy is involved in the development of secondary brain injury following cerebral ischemia-reperfusion injury in rats. This current study aimed to investigate the role of TMEM166 in ischemic stroke following CEA. In the clinical part of this study, the quantitative analysis demonstrated circulating TMEM166, interleukin 6 (IL-6), and C-reactive protein (CRP) levels were significantly elevated in patients who suffered an ischemic stroke after CEA compared to those who did not. Furthermore, non-survivors exhibited higher levels of these proteins than survivors. In the preclinical part of this study, a middle cerebral artery occlusion (MCAO) model was implemented following CAS simulation in TMEM166-/- mice. We found TMEM166 expression was positively correlated with the degree of ischemic brain injury. Ad5-TMEM166 transfection aggravated ischemic brain injury by inducing microglial autophagy activation and release of inflammatory cytokines. Accordingly, TMEM166 deficiency reduced brain inflammation and inhibited excessive microglial autophagy through the mammalian target of rapamycin (mTOR) pathway. These findings suggest that TMEM166 may play a key role in the development of ischemic injury after CEA and may serve as a biomarker for risk assessment of postoperative ischemic stroke.

Risk Factors for Adjacent Segment Disease in Short Segment Lumbar Interbody Fusion-A Case Series.

BACKGROUND: Adjacent segment disease (ASD) is a common problem after lumbar spinal fusions. Ways to reduce the rates of ASD are highly sought after to reduce the need for reoperation. OBJECTIVE: To find predisposing factors of ASD after lumbar interbody fusions, especially in mismatch of pelvic incidence and lumbar lordosis (PI-LL). METHODS: We conducted a retrospective cohort study of all patients undergoing lumbar interbody fusions of less than 4 levels from June 2015 to July 2020 with at least 1 year of follow-up and in those who had obtained postoperative standing X-rays. RESULTS: We found 243 patients who fit inclusion and exclusion criteria. Fourteen patients (5.8%) developed ASD, at a median of 24 months. Postoperative lumbar lordosis was significantly higher in the non-ASD cohort (median 46.4° ± 1.4° vs 36.9° ± 3.6°, P < .001), pelvic tilt was significantly lower in the non-ASD cohort (16.0° ± 0.66° vs 20.3° ± 2.4°, P = .002), PI-LL mismatch was significantly lower in the non-ASD cohort (5.28° ± 1.0° vs 17.1° ± 2.0°, P < .001), and age-appropriate PI-LL mismatch was less common in the non-ASD cohort (34 patients [14.8%] vs 13 [92.9%] of patients with high mismatch, P < .001). Using multivariate analysis, greater PI-LL mismatch was predictive of ASD (95% odds ratio CI = 1.393-2.458, P < .001) and age-appropriate PI-LL mismatch was predictive of ASD (95% odds ratio CI = 10.8-970.4, P < .001). CONCLUSION: Higher PI-LL mismatch, both age-independent and when adjusted for age, after lumbar interbody fusion was predictive for developing ASD. In lumbar degenerative disease, correction of spinopelvic parameters should be a main goal of surgical correction.

The Role of Oxidative Stress in the Progression of Secondary Brain Injury Following Germinal Matrix Hemorrhage.

Germinal matrix hemorrhage (GMH) can be a fatal condition responsible for the death of 1.7% of all neonates in the USA. The majority of GMH survivors develop long-term sequalae with debilitating comorbidities. Higher grade GMH is associated with higher mortality rates and higher prevalence of comorbidities. The pathophysiology of GMH can be broken down into two main titles: faulty hemodynamic autoregulation and structural weakness at the level of tissues and cells. Prematurity is the most significant risk factor for GMH, and it predisposes to both major pathophysiological mechanisms of the condition. Secondary brain injury is an important determinant of survival and comorbidities following GMH. Mechanisms of brain injury secondary to GMH include apoptosis, necrosis, neuroinflammation, and oxidative stress. This review will have a special focus on the mechanisms of oxidative stress following GMH, including but not limited to inflammation, mitochondrial reactive oxygen species, glutamate toxicity, and hemoglobin metabolic products. In addition, this review will explore treatment options of GMH, especially targeted therapy.

Kyphoplasty of C2 Pathological Fractures Using an Anterior Midline Approach and Steerable Osteotome: Technical Note and Case Series.

BACKGROUND: Malignant lesions involving the C2 vertebral body (axis) may be challenging to treat, and not all patients with cancer are good candidates for posterior cervical or occipitocervical instrumentation. OBJECTIVE: To describe a modified technique of the direct anterolateral C2 kyphoplasty using a steerable osteotome, commonly used for the treatment of thoracolumbar spinal lesions. We also report a case series of 11 patients treated with this technique at our institution. METHODS: The authors performed a retrospective review of all patients who underwent a C2 kyphoplasty using the anterior midline approach from 2010 to 2020. Patient demographics, tumor characteristics, pain severity (visual analog scale), Karnofsky performance status , perioperative complications, and postoperative spinal stability were assessed. RESULTS: The main indication for a C2 kyphoplasty was refractory neck pain. All patients tolerated the procedure well. There were no intraoperative complications. One patient developed transient dysphagia. Visual analog scale scores were 9.00 ± 1.10 preoperative and 3.73 ± 1.85 at 2 weeks and 1.67 ± 1.66 at 3 months after the procedure and continued to stay low during the remainder of the follow-up (4-60 months). The Karnofsky performance status improved from 72.73 ± 11.04 preoperatively to 82.22 ± 8.33 at 2 weeks and 86.67 ± 5.00 at 3 months after the procedure. There was no evidence of new occurrence or progression of C2 fractures. CONCLUSION: The anterior kyphoplasty using a steerable osteotome for tumors of the axis can result in lasting pain reduction and improved cervical stability while demonstrating a low complication rate.

Neuromuscular Scoliosis: A Dual-Surgeon Approach.

OBJECTIVE: Neuromuscular Scoliosis (NMS) causes severe deformity and operative correction for these patients carries high complication rates. We present a retrospective study comparing a series of consecutive patients who underwent posterior fusion via a single-surgeon (SS) approach with a consecutive series of patients treated via a dual-surgeon (DS) approach. METHODS: Patients with NMS who underwent posterior fusion via a SS approach from 2019 to 2022 were analyzed and compared to a series of patients with NMS who underwent posterior fusion via a DS approach. RESULTS: In the SS group, the average estimated blood loss (EBL) was 675 mL, average length of stay (LOS) was 6.3 days, average operative time (OT) was 6.5 hours, average packed red blood cell transfusion was 1.5 units, with a complication rate of 30%. The DS group had an average EBL of 400 mL, a LOS of 4.8 days, an OT of 4.75 hours, an average packed red blood cell transfusion of 0.8 units, with a complication rate of 20%. The DS approach was significant for a lower EBL, OT (P < 0.001), and LOS (P < 0.03). CONCLUSIONS: This study suggests that for patients with NMS the DS approach decreases OT, EBL, complication rates, and LOS. This further supports that this approach may benefit outcomes in NMS patients.

Resection of Giant Remote Recurrence of Ependymoma After 41 Years.

Ependymomas are rare primary tumors of the brain and spinal cord that arises from the ependymal cell layer. Cranial ependymomas commonly occur in the posterior fossa; however, approximately 30% of all tumors can be found in the supratentorial region. Supratentorial ependymomas have a shorter progression-free and overall survival than their infratentorial counterparts. We present the case of a 47-year-old man who presented with mild left-sided hemiparesis and confusion secondary to a right-sided 8.5 × 6.0 × 6.0 cm frontotemporal neoplasm encasing the ipsilateral internal and middle cerebral arteries. The patient had undergone a suboccipital craniectomy for resection of a posterior fossa ependymoma at 6 years of age (41 years ago). After multidisciplinary discussion, we performed a right frontotemporal craniotomy for tumor resection (Video) using intraoperative navigation, ultrasound, and intraoperative neurophysiological monitoring. While skeletonizing branches of the middle cerebral artery, an M3 branch was injured inadvertently and repaired immediately. Histopathologic specimens were consistent with ependymoma (World Health Organization grade II). A near-total resection was achieved. The patient developed a transient left-sided hemiparesis but improved to full strength on discharge from the hospital.

Topical vancomycin reduces surgical site infections in patients subjected to craniotomy for primary brain tumor resection: A comprehensive cancer center experience.

BACKGROUND: Craniotomies for resection of neoplastic lesions are at increased risk for surgical site infections (SSIs) as compared to non-neoplastic pathologies. SSIs can be detrimental due to delay in pivotal adjuvant therapies. OBJECTIVE: The purpose of this study was to determine the rate of SSI in primary brain tumors, to analyze risk factors, and to evaluate effectiveness of topical vancomycin in reducing SSIs. METHODS: A retrospective cohort study was conducted at a National Cancer Institutedesignated Comprehensive Cancer Center. Patients with primary brain tumors (n = 799) who were subjected to craniotomy from 2004 to 2014 were included. Patient demographics, tumor characteristics, use of topical vancomycin and clinical outcomes were analyzed. RESULTS: Topical vancomycin was associated with a significantly lower rate of SSI (0.8%) compared to standard care (5%), ( p = 0.00071; OR = 0.15; 95% CI = 0.02 - 0.5). Narcotic use ( p = 0.043; OR = 2.24; 95% CI = 0.96 - 4.81), previous brain radiation ( p = 0.043; OR = 2.08; 95% CI = 1.02 - 4.29), length of hospitalization ( p = 0.01; OR= 1.04; 95% CI = 1.01 - 1.08), and 30 day re-operation ( p = 1.58 ×10 -10; OR = 15.23; 95% CI = 7.06 - 32.71) were associated with increased risk for SSI. CONCLUSION: Topical vancomycin effectively reduced the rate of SSI in patients subjected to craniotomy for primary brain tumor resection. Furthermore, preoperative narcotic use, previous head/brain radiation, length of hospitalization, and 30-day reoperation were associated with increased risk of SSI.

Craniocervical Dissociation in Pediatric Patients: Pearls and Pitfalls of Diagnosis and Management.

AIMS: The aims of this study were to document the injury pattern in pediatric traumatic craniocervical dissociation (CCD) and identify features of survivors. METHODS: Pediatric traumatic CCDs, diagnosed between January 2004 and July 2016, were reviewed. Survivors and nonsurvivors were compared. Categorical and continuous variables were analyzed with Fisher exact and t tests, respectively. RESULTS: Twenty-seven children were identified; 10 died (37%). The median age was 60 months (ranges, 6-109 months [survivors], 2-98 months [nonsurvivors]). For survivors, the median follow-up was 13.4 months (range, 1-109 months). The median time to mortality was 1.5 days (range, 1-7 days). The injury modality was motor vehicle collision in 18 (67%), pedestrian struck in 8 (30%), and 1 shaken infant (3%). For nonsurvivors, CCD was equally diagnosed by plain radiograph and head/cervical spine computed tomography scan. For survivors, CCD was diagnosed by computed tomography in 7 (41%), magnetic resonance imaging in 10 (59%), and none by radiograph. Seven diagnosed by magnetic resonance imaging (41%) had nondiagnostic initial imaging but persistent neck pain. Magnetic resonance imaging was obtained and was diagnostic of CCD in all 7 (P < 0.01). Survivors required significantly less cardiopulmonary resuscitation (P < 0.01), had lower Injury Severity Scores (P < 0.01), higher Glasgow Coma Scale scores (P < 0.01), and shorter transport times (P < 0.01). Significantly more involved in motor vehicle collisions survived (P = 0.04). Nine (53%) had no disability at follow-up evaluation. CONCLUSIONS: In pediatric CCD, high-velocity mechanism, cardiac arrest, high Injury Severity Score, and low Glasgow Coma Scale score are associated with mortality. If CCD is correctly managed in the absence of cardiac arrest or traumatic brain or spinal cord injury, children may survive intact.

Percutaneous lumbar pedicle fixation in young children with flexion-distraction injury-case report and operative technique.

Thoracolumbar fractures in children are relatively uncommon and should be regarded as a separate entity from those in adults. While percutaneous pedicle fixation has emerged as an effective alternative to open fixation in adults with unstable thoracolumbar fractures, this technique is rarely applied in children. We report a 6-year-old girl with an L3 chance fracture, which was treated via short-segment percutaneous pedicle fixation. We also discussed the technical challenges and caveats of this surgical technique in young children. While potentially more challenging, percutaneous pedicle fixation is feasible in young children with thoracolumbar fractures. Specific differences between the developing and mature spine in regard to anatomical and biomechanical characteristics, including ligamentous laxity and intrinsic elasticity, should be taken into consideration. Future studies are needed to compare outcomes of minimally invasive spinal techniques to open surgery in children.

Management of Thoracic Disc Herniation Using the Mini-Open Retropleural Approach: Technique Illustration and Clinical Outcomes of 33 Patients From a Single Academic Center.

BACKGROUND: Conventional surgical approaches used in the management of thoracic disc herniation (TDH) are associated with high morbidity. The development of minimally invasive and mini-open approaches has consistently improved patient outcomes. OBJECTIVE: To report our experience and outcomes of patients with symptomatic TDHs who underwent discectomy and partial corpectomy using the mini-open retropleural (MORP) approach as well as provide a detailed and illustrated technical description of the approach. METHODS: Retrospective chart review was performed on all patients with symptomatic TDHs who underwent a MORP approach at a tertiary academic center between 2011 and 2019. Patient demographic, clinical, and imaging data were examined (n = 33). The surgical technique is illustrated and described in detail. RESULTS: Discectomy of the herniated thoracic discs was successfully achieved in all patients using the MORP approach. Calcified discs were present in 63.6% (n = 21) of patients. Immediate instrumentation and fusion were performed in 30.3% (n = 10) of patients, which were among the earlier cases in this series. Symptomatic pleural effusions and cerebrospinal fluid leakage occurred in 6.1% (n = 2) and 9.1% (n = 3), respectively. No patient required chest tube placement. CONCLUSION: The MORP approach described in this manuscript is feasible and safe in achieving discectomy in patients with symptomatic TDHs. Compared to conventional open and other minimally invasive approaches, patients undergoing the MORP approach may have better outcomes with lower complication rates.

Expandable Titanium Cages in the Emergent Treatment of Severe Spinal Deformity Secondary to Osteomyelitis: A Series of Three Complex Cases.

The literature lacks robust evidence on the benefits versus risks of instrumenting and fusing the spinal column in the setting of active osteomyelitis. We report three patients with vertebral osteomyelitis and subsequent severe and complex kyphotic deformities. Patients 1 and 2 had previous instrumentation that required revision because of hardware failure in the thoracic and thoracolumbar regions, respectively. Patient 3 developed a severe cervical kyphotic deformity at 2 months after being diagnosed and treated with antibiotics for osteomyelitis, necessitating emergent instrumentation and fusion. All the three patients are doing very well so far. Spinal instrumentation and fusion for correction of kyphotic deformity is sometimes necessary in the context of active osteomyelitis and should be done emergently and without hesitation when spinal cord injury from spinal instability is of concern.

The Return Back to Typical Practice from the "Battle Plan" of the Coronavirus Disease 2019 (COVID-19) Pandemic: A Comparative Study.

BACKGROUND: Every aspect of the medical field has been heavily affected by the coronavirus disease 2019 (COVID-19) pandemic, and neurosurgical services are no exception. Several departments have reported their experiences and protocols to provide insights for others impacted. The goals of this study are to report the load and variety of neurosurgical cases and clinic visits after discontinuing the COVID-19 Battle Plan at an academic tertiary care referral center to provide insights for other departments going through the same transition. METHODS: The clinical data of all patients who underwent a neurosurgical intervention between May 4, 2020, and June 4, 2020 were obtained from a prospectively maintained database. Data of the control group were retrospectively collected from the medical records to compare the types of surgeries/interventions and clinic visits performed by the same neurosurgical service before the COVID-19 pandemic started. RESULTS: One hundred sixty-one patients underwent neurosurgical interventions, and seven-hundred one patients were seen in clinic appointments, in the 4-week period following easing back from our COVID-19 "Battle Plan." Discontinuing the "Battle Plan" resulted in increases in case load to above-average practice after a week but a continued decrease in clinic appointments throughout the 4 weeks compared with average practice. CONCLUSIONS: As policy-shaping crises like pandemics abate, easing back to "typical" practice can be completed effectively by appropriately allocating resources. This can be accomplished by anticipating increases in neurosurgical volume, specifically in the functional/epilepsy and brain tumor subspecialties, as well as continued decreases in neurosurgical clinic volume, specifically in elective spine.

Novel Titanium Cages for Minimally Invasive Lateral Lumbar Interbody Fusion: First Assessment of Subsidence.

INTRODUCTION: Implant subsidence is a potential complication of spinal interbody fusion and may negatively affect patients subjected to procedures relying on indirect decompression such as minimally invasive transpsoas lateral lumbar interbody fusion (LLIF). The porous architecture of a recently developed titanium intervertebral cage maximizes bone-to-implant contact and minimizes stress shielding in laboratory experiments; however, its subsidence rate in patients has not yet been evaluated. The goal of this current study was to evaluate implant subsidence in patients subjected to LLIF. METHODS: Our institutional review board-approved single-center experience included 29 patients who underwent 30 minimally invasive LLIF from July 2017 to September 2018 utilizing the novel 3D-printed porous titanium implants. Radiographs, obtained during routine postoperative follow-up visits, were reviewed for signs of implant subsidence, defined as any appreciable compromise of the vertebral endplates. RESULTS: Radiographic subsidence occurred in 2 cases (6.7%), involving 2 out of 59 porous titanium interbody cages (3.4%). Both cases of subsidence occurred in four-level stand-alone constructs. The patients remained asymptomatic and did not require surgical revision. Ten surgeries were stand-alone constructs, and 20 surgeries included supplemental posterior fixation. CONCLUSIONS: In our patient cohort, subsidence of the porous titanium intervertebral cage occurred in 6.7% of all cases and in 3.4% of all lumbar levels. This subsidence rate is lower compared to previously reported subsidence rates in patients subjected to LLIF using polyetheretherketone implants.