Invasive devices to monitor the intraspinal perfusion pressure in the hemodynamic management of acute spinal cord injury: A systematic scoping review.

BACKGROUND: Various methods for measuring intrathecal pressure (ITP) after spinal cord injury (SCI) to guide hemodynamic management have been investigated. To synthesize the current literature, this current study conducted a scoping review of the use of intrathecal devices to monitor ITP during acute management of SCI with the aim of understanding the association between ITP monitoring with physiological and clinical outcomes. METHODS: A systematic review of literature following the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. All eligible studies were screened for inclusion and exclusion criteria. Data extracted included number of patients included, severity of injury, characteristics of the intervention-intrathecal device used to record the ITP, outcomes -hemodynamic parameters observed, changes in the American Spinal Injury Association (ASIA) Impairment Scale (AIS), total motor scores, association of ITP with other physiological variables. RESULTS: The search yielded a total of 1,698 articles, of which 30 observational studies and 2 randomized clinical trials were deemed eligible based on their use of an intrathecal invasive device to monitor spinal cord perfusion pressure (SCPP) in patients with SCI. Of these, 9 studies used a lumbar drain, 23 a Codman pressure probe and 1 study that used both. These studies underscore the crucial interplay between ITP, the SCPP and physiological variables, with neurological outcome. It is still unclear whether monitoring from a lumbar drain is accurate enough to highlight what is occurring at the site of SCI, which is the main advantage of Codman Probe, however, the latter requires specialized personnel that may not be available in most settings. Minor adverse effects were associated with lumbar drain catheters, while cerebrospinal fluid leak requiring repair (~ 7%) is the main concern with Codman Probes. CONCLUSION: Future investigation of SCPP protocols via lumbar drains and Codman probes ought to involve multi-centered randomized controlled trials and continued translational investigation with animal models.

Virtual, Augmented, and Mixed Reality Applications for Surgical Rehearsal, Operative Execution, and Patient Education in Spine Surgery: A Scoping Review.

Background and Objectives: Advances in virtual reality (VR), augmented reality (AR), and mixed reality (MR) technologies have resulted in their increased application across many medical specialties. VR's main application has been for teaching and preparatory roles, while AR has been mostly used as a surgical adjunct. The objective of this study is to discuss the various applications and prospects for VR, AR, and MR specifically as they relate to spine surgery. Materials and Methods: A systematic review was conducted to examine the current applications of VR, AR, and MR with a focus on spine surgery. A literature search of two electronic databases (PubMed and Scopus) was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The study quality was assessed using the MERSQI score for educational research studies, QUACS for cadaveric studies, and the JBI critical appraisal tools for clinical studies. Results: A total of 228 articles were identified in the primary literature review. Following title/abstract screening and full-text review, 46 articles were included in the review. These articles comprised nine studies performed in artificial models, nine cadaveric studies, four clinical case studies, nineteen clinical case series, one clinical case-control study, and four clinical parallel control studies. Teaching applications utilizing holographic overlays are the most intensively studied aspect of AR/VR; the most simulated surgical procedure is pedicle screw placement. Conclusions: VR provides a reproducible and robust medium for surgical training through surgical simulations and for patient education through various platforms. Existing AR/MR platforms enhance the accuracy and precision of spine surgeries and show promise as a surgical adjunct.

Utilization of Augmented Reality Head-Mounted Display for the Surgical Management of Thoracolumbar Spinal Trauma.

Background and Objectives: Augmented reality head-mounted display (AR-HMD) is a novel technology that provides surgeons with a real-time CT-guided 3-dimensional recapitulation of a patient's spinal anatomy. In this case series, we explore the use of AR-HMD alongside more traditional robotic assistance in surgical spine trauma cases to determine their effect on operative costs and perioperative outcomes. Materials and Methods: We retrospectively reviewed trauma patients who underwent pedicle screw placement surgery guided by AR-HMD or robotic-assisted platforms at an academic tertiary care center between 1 January 2021 and 31 December 2022. Outcome distributions were compared using the Mann-Whitney U test. Results: The AR cohort (n = 9) had a mean age of 66 years, BMI of 29.4 kg/m2, Charlson Comorbidity Index (CCI) of 4.1, and Surgical Invasiveness Index (SII) of 8.8. In total, 77 pedicle screws were placed in this cohort. Intra-operatively, there was a mean blood loss of 378 mL, 0.78 units transfused, 398 min spent in the operating room, and a 20-day LOS. The robotic cohort (n = 13) had a mean age of 56 years, BMI of 27.1 kg/m2, CCI of 3.8, and SII of 14.2. In total, 128 pedicle screws were placed in this cohort. Intra-operatively, there was a mean blood loss of 432 mL, 0.46 units transfused units used, 331 min spent in the operating room, and a 10.4-day LOS. No significant difference was found between the two cohorts in any outcome metrics. Conclusions: Although the need to address urgent spinal conditions poses a significant challenge to the implementation of innovative technologies in spine surgery, this study represents an initial effort to show that AR-HMD can yield comparable outcomes to traditional robotic surgical techniques. Moreover, it highlights the potential for AR-HMD to be readily integrated into Level 1 trauma centers without requiring extensive modifications or adjustments.

Metastasectomy for extracalvarial renal cell carcinoma.

Key Clinical Message: Palliative surgical resection of extra-calvarial metastatic lesions from renal cell tumors is crucial for controlling metastatic spread, improving quality of life, and preventing associated morbidity. Careful surgical planning, including selective preoperative embolization and controlled resection around critical structures such as the sagittal sinus, is essential for successful outcomes. Cranioplasty with Titanium mesh and bone cement post-resection can provide symptomatic relief, better cosmesis, and overall improved quality of life. Abstract: Renal cell carcinomas are aggressive tumors with distant systemic disease. The calvarium appears to be an unusual and rare site for distant metastasis. The treatment modalities are challenging and out of the normal realm for the management of these tumors. We report a case of a 63-year-old woman with a previous history of nephrectomy who presented with symptoms of severe headaches, and swelling of bi-frontal and bi-parietal scalp regions due to multifocal extracalvarial disease. Preoperative bilateral superficial temporal artery embolization was performed to control the intraoperative bleeding. Surgical technique has been described with the critical steps involved, and a literature review has been conducted. Palliative tumor resection surgery was performed to improve the patient's quality of life as well as to confirm the histopathological diagnosis. Gross total resection of the extracalvarial metastatic tumor was achieved. Biopsy confirmed renal cell tumor with the clear cell subtype. The patient recovered well from her surgery with slow healing of the scalp wound. At 6-month follow-up, no recurrence of the extracalvarial disease was observed on serial imaging. Extracalvarial metastasis is a rare presentation in renal cell carcinoma. Considering the inherent radioresistant nature of the tumor, palliative surgical resection can be offered to control the metastatic spread, relieve agonizing pain symptoms, and to improve the quality of life. Preoperative embolization helps to decrease intraoperative blood loss. Moreover, palliative surgical resection of extracalvarial diseases helps to treat the metastasis as well as avoiding the associated morbidity that may occur if left untreated.

Anomalous Left Superior Vena Cava Predisposing to Recurrent Brain Abscesses: A Case Report and Review of the Literature.

Brain abscess is a devastating illness, with a high risk of morbidity and mortality. Recurrent brain abscess poses a challenge to diagnosis while treatment options may differ. Right to left shunt is a lesser-explored etiology for recurrent brain abscesses. PubMed literature review was performed to study all published studies with reference to right to left cardiac shunt as a possible etiology for the recurrent brain abscesses. The authors also report a case of a young male who developed recurrent brain abscess after previous resection and treatment. Right to left cardiac shunting of deoxygenated blood is an etiology for recurrent brain abscess formation. Thorough systemic workup and multispecialty treatment is recommended to treat this relatively uncommon presentation.

A Meta-Analysis of Surgical Outcomes in 25727 Patients Undergoing Anterior Cervical Discectomy and Fusion or Anterior Cervical Corpectomy and Fusion for Cervical Deformity.

STUDY DESIGN: Systematic Review. OBJECTIVES: To evaluate which cervical deformity correction technique between anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) produces better clinical, radiographic, and operative outcomes. METHODS: We conducted a meta-analysis comparing studies involving ACDF and ACCF. Adult patients with either original or previously treated cervical spine deformities were included. Two independent reviewers categorized extracted data into clinical, radiographic, and operative outcomes, including complications. Clinical assessments included patient-reported outcomes; radiographic evaluations examined C2-C7 Cobb angle, T1 slope, T1-CL, C2-7 SVA, and graft stability. Surgical measures included surgery duration, blood loss, hospital stay, and complications. RESULTS: 26 studies (25727 patients) met inclusion criteria and were extracted. Of these, 14 studies (19077 patients) with low risk of bias were included in meta-analysis. ACDF and ACCF similarly improve clinical outcomes in terms of JOA and NDI, but ACDF is significantly better at achieving lower VAS neck scores. ACDF is also more advantageous for improving cervical lordosis and minimizing the incidence of graft complications. While there is no significant difference between approaches for most surgical complications, ACDF is favorable for reducing operative time, intraoperative blood loss, and length of hospital stay. CONCLUSIONS: While both techniques benefit cervical deformity patients, when both techniques are feasible, ACDF may be superior with respect to VAS neck scores, cervical lordosis, graft complications and certain perioperative outcomes. Further studies are recommended to address outcome variability and refine surgical approach selection.

Current Applications and Future Implications of Artificial Intelligence in Spine Surgery and Research: A Narrative Review and Commentary.

STUDY DESIGN: Narrative review. OBJECTIVES: Artificial intelligence (AI) is being increasingly applied to the domain of spine surgery. We present a review of AI in spine surgery, including its use across all stages of the perioperative process and applications for research. We also provide commentary regarding future ethical considerations of AI use and how it may affect surgeon-industry relations. METHODS: We conducted a comprehensive literature review of peer-reviewed articles that examined applications of AI during the pre-, intra-, or postoperative spine surgery process. We also discussed the relationship among AI, spine industry partners, and surgeons. RESULTS: Preoperatively, AI has been mainly applied to image analysis, patient diagnosis and stratification, decision-making. Intraoperatively, AI has been used to aid image guidance and navigation. Postoperatively, AI has been used for outcomes prediction and analysis. AI can enable curation and analysis of huge datasets that can enhance research efforts. Large amounts of data are being accrued by industry sources for use by their AI platforms, though the inner workings of these datasets or algorithms are not well known. CONCLUSIONS: AI has found numerous uses in the pre-, intra-, or postoperative spine surgery process, and the applications of AI continue to grow. The clinical applications and benefits of AI will continue to be more fully realized, but so will certain ethical considerations. Making industry-sponsored databases open source, or at least somehow available to the public, will help alleviate potential biases and obscurities between surgeons and industry and will benefit patient care.

Posterior Transdural Approach for Thoracic Corpectomies in the Setting of Complex Spine Deformity Reconstruction.

BACKGROUND AND OBJECTIVE: There are many surgical approaches for execution of a thoracic corpectomy. In cases of challenging deformity, traditional posterior approaches might not be sufficient to complete the resection of the vertebral body. In this technical note, we describe indications and technique for a transdural multilevel high thoracic corpectomy. METHODS: A 25-year-old man with a history of neurofibromatosis type 1 presented with instrumentation failure after a previous T1-T12 posterior spinal fusion, extensive laminectomy, and tumor resection. The patient presented with progressive back pain, had broad dural ectasia, and a progressive kyphotic rotational and anteriorly translated spinal deformity. To resect the medial-most aspect of the vertebral body, a bilateral extracavitary approach was attempted, but was found insufficient. A transdural approach was subsequently performed. A left paramedian durotomy was made, followed by generous arachnoid dissection, bilateral dentate ligament division, and T4 rootlet sacrifice to mobilize the spinal cord. A ventral durotomy was then made and the ventral dura was reflected over the spinal cord to protect it while drilling. The corpectomy was then completed. The ventral and dorsal durotomies were closed primarily and reinforced with fibrin glue and fibrin sealant patch. The corpectomy defect was filled with nonstructural autograft. RESULTS: The focal kyphosis was corrected with a combination of rod contouring, compression, and in situ bending. During the surgery, the patient had stable neuromonitoring data, and postoperatively had no neurological deficits. On follow-up until 1 year, the patient presented with no signs of cerebrospinal spinal leaks, no motor or sensory deficits, minimal incisional pain, and significantly improved posture. CONCLUSION: Complex high thoracic (T3-5) ventral pathology inaccessible via a bilateral extracavitary approach may be accessed via a transdural approach as opposed to an anterior/lateral transthoracic approach that requires mobilization of cardiovascular structures or scapula.

Surgical Perfusion and Isolation of the Porcine Pancreas for Islet Isolation.

Pancreatic islet transplantation is an emerging treatment for type I diabetes; however, it is limited by donor matching and availability. Porcine islet xenotransplantation offers a promising alternative to allotransplantation, with the potential for large-scale production of on-demand, functional islets. The yield and viability of isolated islets is highly susceptible to the quality of the donor pancreas and the method of procurement, particularly the duration of warm-ischemia time. To improve organ preservation and subsequent islet yield and viability, we have developed a protocol for surgical perfusion and resection of the porcine pancreas. This protocol employs direct infrarenal aortic cannulation and organ perfusion to both minimize warm-ischemia time and simplify the procedure for operators who do not have extensive surgical expertise. Subsequent arterial perfusion of the pancreas via the aorta flushes stagnant blood from the microvasculature, thereby reducing thrombosis and oxidative damage to the tissue. This manuscript provides a detailed protocol for surgical perfusion and resection of the porcine pancreas, followed by islet isolation and purification.

Pedicle screw placement in the cervical vertebrae using augmented reality-head mounted displays: a cadaveric proof-of-concept study.

BACKGROUND: The accurate and safe positioning of cervical pedicle screws is crucial. While augmented reality (AR) use in spine surgery has previously demonstrated clinical utility in the thoracolumbar spine, its technical feasibility in the cervical spine remains less explored. PURPOSE: The objective of this study was to assess the precision and safety of AR-assisted pedicle screw placement in the cervical spine. STUDY DESIGN: In this experimental study, 5 cadaveric cervical spine models were instrumented from C3 to C7 by 5 different spine surgeons. The navigation accuracy and clinical screw accuracy were evaluated. METHODS: Postprocedural CT scans were evaluated for clinical accuracy by 2 independent neuroradiologists using the Gertzbein-Robbins scale. Technical precision was assessed by calculating the angular trajectory (°) and linear screw tip (mm) deviations in the axial and sagittal planes from the virtual pedicle screw position as recorded by the AR-guided platform during the procedure compared to the actual pedicle screw position derived from postprocedural imaging. RESULTS: A total of forty-one pedicle screws were placed in 5 cervical cadavers, with each of the 5 surgeons navigating at least 7 screws. Gertzbein-Robbins grade of A or B was achieved in 100% of cases. The mean values for tip and trajectory errors in the axial and sagittal planes between the virtual versus actual position of the screws was less than 3 mm and 30°, respectively (p<.05). None of the cervical screws violated the cortex by more than 2 mm or displaced neurovascular structures. CONCLUSIONS: AR-assisted cervical pedicle screw placement in cadavers demonstrated clinical accuracy comparable to existing literature values for image-guided navigation methods for the cervical spine. CLINICAL SIGNIFICANCE: This study provides technical and clinical accuracy data that supports clinical trialing of AR-assisted subaxial cervical pedicle screw placement.

Use of a novel donor lung scoring system as a tool for increasing lung recovery for transplantation.

BACKGROUND: There is a critical shortage of donor lungs for transplantation. We previously developed a parsimonious, highly discriminatory 9-variable Lung Donor (LUNDON) acceptability score. Here we assessed the utility of this score as a tool for improving lung recovery rates for transplantation. METHODS: We examined all brain-dead donors between 2014 and 2020 from 3 US organ procurement organizations and validated the score's predictive performance. We examined the trajectory of donors with low (<40) and high (>60) initial LUNDON scores, their corresponding lung recovery rates, factors contributing to score improvement using multivariable regression models, and 1-year post-transplant recipient survival. RESULTS: Overall lung recovery was 32.4% (1410 of 4351). Validation of the LUNDON score in our cohort revealed a C statistic of 0.904 and required intercept calibration. Low initial LUNDON donors that improved to a high final score had an increase in lung recovery rate from 29.3% (1100 of 3765) to 86.8% (441 of 508), associated with lower body mass index, management in a specialized donor care facility (SDCF), and more bronchoscopies. Donors with high initial and final LUNDON scores had a lung recovery rate of 85.2% (98 of 115), associated with shorter length of hospital stay. One-year survival was similar in recipients of low-to-high versus high-to-high LUNDON score donors (0.89 vs 0.84; P = .2). CONCLUSIONS: The LUNDON score performs well as a predictor of lung recovery in a contemporary cohort but may require organ procurement organization-specific calibration. SDCF care, increasing use of bronchoscopy, and decreasing the time from brain death to organ procurement may improve lung utilization. The LUNDON score can be used to guide donor management to expand the donor pool.

The Perfect Storm: An Unusual Cause of Intestinal Perforation in a Solid Organ Transplant Patient.

Immunosuppressants are used to prevent rejection in transplant patients. Many of these medications commonly cause gastrointestinal (GI) symptoms. We present a 38-year-old kidney and pancreas transplant recipient who had severe ulceration throughout his GI tract leading to perforations of his stomach and cecum, despite early discontinuation of mycophenolate mofetil-the most likely culprit medication. The ongoing injury observed despite holding mycophenolate suggests a possible compounding effect of tacrolimus and everolimus. Both these agents are underrepresented causes of GI injury. This perfect storm of agents may have accounted for the severity and extensive presentation observed in our patient.