A case of primary central nervous system lymphoma presenting as a shunt complication.

The authors describe an 82-year-old female with a right frontal ventriculoperitoneal (VP) shunt for long-standing normal pressure hydrocephalus (NPH) who presented with worsening incontinence and gait instability. She was found to have right lateral ventricle collapse around the shunt catheter and subsequently underwent shunt revision, which failed to improve her symptoms. Magnetic resonance imaging (MRI) was obtained on postoperative day two, which demonstrated a ventricular lesion. Endoscopic brain biopsy was performed and a diagnosis of primary central nervous system lymphoma (PCNSL) was made. The authors believe this is the first published case of PCNSL presenting as a VP shunt complication in a patient with NPH.

New-onset Geriatric Epilepsy in a Latin American Country: A Multi-centric Study from Mexico.

Background: In Latin America, epilepsy in the elderly is a neglected issue that has never been studied. The epidemiological transition has significantly altered the demographics of epilepsy, and therefore, we would like to draw attention to this topic. Objective: We require local real-world evidence, as the literature often depicts a different scenario, including pharmacological management. Methods: From 2007 to 2018, we recruited all patients with new-onset geriatric epilepsy (first seizure after the age of 60) tracked from ten Mexican hospitals, adding them to patients with similar characteristics from a previously published study. The diagnosis was confirmed in all patients by a certified neurologist, and they were also studied using a conventional electroencephalogram and imaging workup. Results: A diagnosis of new-onset geriatric epilepsy (Elderly patients was established in 100 cases. No specific cause was found in 26% of patients, while 42% had a stroke and 10% had neurocysticercosis (NCC). Monotherapy was the choice in 83 patients, and phenytoin was the most used drug (50%), followed by carbamazepine (25%). Conclusion: NCC remains a frequent cause of new-onset geriatric epilepsy. This distribution is not seen in the literature, mainly representing patients from wealthy economies. In our setting, financial constraints influence the choice of the drug, and newer antiepileptic drugs should be made more affordable to this population with economic and physical frailty.

Cervical intramedullary teratoma: a case report and systematic review of the literature.

Here, we report a case of a 3-year-old female who presented to clinic with an enlarging mass in the posterior cervical midline. The mass was present since birth and demonstrated no cutaneous stigmata. Plain film, CT, and MRI of the cervical spine (C3-C5) revealed enlargement of the spinal canal, soft tissue calcification, spinal dysraphism, and an intramedullary, predominantly fatty, mass. The mass had associated calcifications and a highly proteinaceous cyst. Surgical resection of the spinal lesion was subsequently performed. Histopathological evaluation revealed a mature teratoma. Cervical spinal teratomas in the pediatric population are rare entities with few cases currently reported in the literature. We conducted a systematic review to outline the current evidence detailing cases of intramedullary spinal cord teratomas. Six articles were included for final review. All patients in the included articles underwent maximal surgical resection with one patient also receiving chemotherapy and radiation. With our report, we aim to add to the literature on cervical intramedullary spinal cord teratomas in the pediatric population.

Immunotherapeutic treatments for spinal and peripheral nerve tumors: a primer.

OBJECTIVE: Spinal and peripheral nerve tumors are a heterogeneous group of neoplasms that can be associated with significant morbidity and mortality despite the current standard of care. Immunotherapy is an emerging therapeutic option to improve the prognoses of these tumors. Therefore, the authors sought to present an updated and unifying review on the use of immunotherapy in treating tumors of the spinal cord and peripheral nerves, including a discussion on mechanism of action, drug delivery, current treatment techniques, and preclinical and clinical studies. METHODS: Current data in the literature regarding immunotherapy were collated and summarized. Targeted tumors included primary and secondary spinal tumors, as well as peripheral nerve tumors. RESULTS: Four primary modalities of immunotherapy (CAR T cell, monoclonal antibody, viral, and cytokine) have been reported to target spine and peripheral nerve tumors. Of the primary spinal tumors, spinal cord astrocytomas had the most preclinical evidence supporting immunotherapy success with CAR T-cell therapy targeting the H3K27M mutation, whereas spinal schwannomas and ependymomas had the most evidence reported for monoclonal antibody therapy preclinically. Of the secondary spinal tumors, primary CNS lymphomas demonstrated some clinical response to immunotherapy, whereas multiple myeloma and bone tumor experiences with immunotherapy were largely limited to concept only. Within peripheral nerve tumors, the use of immunotherapy to treat neurofibromas in the setting of syndromes has been suggested in theory, and possible immunotherapeutic targets have been identified in malignant peripheral nerve tumors. To date, there have been 2 clinical trials involving spine tumors and 2 clinical trials involving peripheral nerve tumors that have reported results, all of which are promising but require validation. CONCLUSIONS: Immunotherapy to treat spinal and peripheral nerve tumors has become an emerging area of research and interest. A large amount of preclinical data supporting the translation of this therapy into practice, aimed at ameliorating the poor prognoses of specific tumors, have been reported. Future clinical studies for translation will focus on the optimal therapy type and administration route to best target these tumors, which often preclude total surgical resection given their proximity to the neural and vascular elements of the spine.

The role of an anterior approach in the treatment of ankylosing spondylitis-associated cervical fractures: a systematic review and meta-analysis.

OBJECTIVE: Cervical fractures in patients with ankylosing spondylitis can have devastating neurological consequences. Currently, several surgical approaches are commonly used to treat these fractures: anterior, posterior, and anterior-posterior. The relative rarity of these fractures has limited the ability of surgeons to objectively determine the merits of each. The authors present an updated systematic review and meta-analysis investigating the utility of anterior surgical approaches relative to posterior and anterior-posterior approaches. METHODS: After a comprehensive literature search of the PubMed, Cochrane, and Embase databases, 7 clinical studies were included in the final qualitative and 6 in the final quantitative analyses. Of these studies, 6 compared anterior approaches with anterior-posterior and posterior approaches, while 1 investigated only an anterior approach. Odds ratios and 95% confidence intervals were calculated where appropriate. RESULTS: A meta-analysis of postoperative neurological improvement revealed no statistically significant differences in gross rates of neurological improvement between anterior and posterior approaches (OR 0.40, 95% CI 0.10-1.59; p = 0.19). However, when analyzing the mean change in neurological function, patients who underwent anterior approaches had a significantly lower mean change in postoperative neurological function relative to patients who underwent posterior approaches (mean difference [MD] -0.60, 95% CI -0.76 to -0.45; p < 0.00001). An identical trend was seen between anterior and anterior-posterior approaches; there were no statistically significant differences in gross rates of neurological improvement (OR 3.05, 95% CI 0.84-11.15; p = 0.09). However, patients who underwent anterior approaches experienced a lower mean change in neurological function relative to anterior-posterior approaches (MD -0.46, 95% CI -0.60 to -0.32; p < 0.00001). There were no significant differences in complication rates between anterior approaches, posterior approaches, or anterior-posterior approaches, although complication rates trended lower in patients who underwent anterior approaches. CONCLUSIONS: The results of this review and meta-analysis demonstrated the varying benefits of anterior approaches relative to posterior and anterior-posterior approaches in treatment of cervical fractures associated with ankylosing spondylitis. While reports demonstrated lower degrees of neurological improvement in anterior approaches, they may benefit patients with less-severe injuries if lower complication rates are desired.

Spinal anesthesia in awake surgical procedures of the lumbar spine: a systematic review and meta-analysis of 3709 patients.

OBJECTIVE: Awake surgery has previously been found to improve patient outcomes postoperatively in a variety of procedures. Recently, multiple groups have investigated the utility of this modality for use in spine surgery. However, few current meta-analyses exist comparing patient outcomes in awake spinal anesthesia with those in general anesthesia. Therefore, the authors sought to present an updated systematic review and meta-analysis investigating the utility of spinal anesthesia relative to general anesthesia in lumbar procedures. METHODS: Following a comprehensive literature search of the PubMed and Cochrane databases, 14 clinical studies were included in our final qualitative and quantitative analyses. Of these studies, 5 investigated spinal anesthesia in lumbar discectomy, 4 discussed lumbar laminectomy, and 2 examined interbody fusion procedures. One study investigated combined lumbar decompression and fusion or decompression alone. Two studies investigated patients who underwent discectomy and laminectomy, and 1 study investigated a series of patients who underwent transforaminal lumbar interbody fusion, posterolateral fusion, or decompression. Odds ratios, mean differences (MDs), and 95% confidence intervals were calculated where appropriate. RESULTS: A meta-analysis of the total anesthesia time showed that time was significantly less in patients who received spinal anesthesia for both lumbar discectomies (MD -26.53, 95% CI -38.16 to -14.89; p = 0.00001) and lumbar laminectomies (MD -11.21, 95% CI -19.66 to -2.75; p = 0.009). Additionally, the operative time was significantly shorter in patients who underwent spinal anesthesia (MD -14.94, 95% CI -20.43 to -9.45; p < 0.00001). Similarly, when analyzing overall postoperative complication rates, patients who received spinal anesthesia were significantly less likely to experience postoperative complications (OR 0.29, 95% CI 0.16-0.53; p < 0.0001). Furthermore, patients who received spinal anesthesia had significantly lower postoperative pain scores (MD -2.80, 95% CI -4.55 to -1.06; p = 0.002). An identical trend was seen when patients were stratified by lumbar procedures. Patients who received spinal anesthesia were significantly less likely to require postoperative analgesia (OR 0.06, 95% CI 0.02-0.25; p < 0.0001) and had a significantly shorter hospital length of stay (MD -0.16, 95% CI -0.29 to -0.03; p = 0.02) and intraoperative blood loss (MD -52.36, 95% CI -81.55 to -23.17; p = 0.0004). Finally, the analysis showed that spinal anesthesia cost significantly less than general anesthesia (MD -226.14, 95% CI -324.73 to -127.55; p < 0.00001). CONCLUSIONS: This review has demonstrated the varying benefits of spinal anesthesia in awake spine surgery relative to general anesthesia in patients who underwent various lumbar procedures. The analysis has shown that spinal anesthesia may offer some benefits when compared with general anesthesia, including reduction in the duration of anesthesia, operative time, total cost, and postoperative complications. Large prospective trials will elucidate the true role of this modality in spine surgery.

Antiresorptive and anabolic medications used in the perioperative period of patients with osteoporosis undergoing spine surgery: their impact on the biology of fusion and systematic review of the literature.

OBJECTIVE: Osteoporosis represents the most common metabolic disease of the bone, with an estimated 10% of adults aged 50 years or older affected in the United States. This patient population is at increased risk for spine fracture and instrumentation-related complications after spine surgery. Surgeon knowledge of the available treatments for patients with low bone mineral density (BMD) and how they impact biology of fusion may help mitigate negative effects in the postoperative period. Recombinant parathyroid hormone, which is sold under the name teriparatide, is the most extensively studied bone-protecting agent in humans. Additionally, the success of the monoclonal antibody denosumab has led to further clinical investigations of human patients undergoing spine surgery. Another monoclonal antibody, romosozumab, was recently approved by the US FDA for human use in patients with osteoporosis. Although studies of romosozumab in patients undergoing spine surgery have not been conducted, this is a promising potential therapeutic agent based on its early success in preclinical and clinical trials. Here, the authors aimed to review the mechanisms of action and evidence of use of antiresorptive and anabolic agents in patients with osteoporosis undergoing spine surgery. METHODS: In accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was conducted to explore the antiresorptive and anabolic agents used in the perioperative period in patients with osteoporosis undergoing spinal surgery. The search was performed by using the PubMed, Embase, and Cochrane Library databases. Titles and abstracts were screened and subsequently selected for full review. RESULTS: The initial search returned 330 articles. Of these articles, 23 final articles were included and reviewed. Many of these articles reported that use of adjuvant agents in the perioperative period improved radiographic evidence of bony fusion and bone fusion rates. These agents tended to improve BMD postoperatively. CONCLUSIONS: Although antiosteoporosis agents are effective to varying degrees as treatments of patients with low BMD, teriparatide and bisphosphonates have been the most extensively studied with respect to spinal instrumentation. The advent of newer agents represents an area for further exploration, especially due to the current paucity of controlled investigations. It is imperative for spine surgeons to understand the mechanisms of action of these drugs and their effects on biology of fusion.

Osteoporosis treatment in patients undergoing spinal fusion: a systematic review and meta-analysis.

OBJECTIVE: Bisphosphonates and teriparatide are the most common therapies used in the treatment of osteoporosis. Their impact on fusion rates in osteoporotic patients following spinal fusion has yet to be concretely defined, with previous systematic reviews focusing heavily on bisphosphonates and lacking clinical insight on the utility of teriparatide. Herein the authors present an updated meta-analysis of the utility of both bisphosphonates and teriparatide in improving spinal fusion outcomes in osteoporotic patients. METHODS: After a comprehensive search of the English-language literature in the PubMed and Embase databases, 11 clinical studies were included in the final qualitative and quantitative analyses. Of these studies, 9 investigated bisphosphonates, 7 investigated teriparatide, and 1 investigated a combination of teriparatide and denosumab. Odds ratios and 95% confidence intervals were calculated where appropriate. RESULTS: A meta-analysis of the postoperative use of bisphosphonate demonstrated better odds of successful fusion as compared to that in controls during short-term monitoring (OR 3.33, 95% CI 1.72-6.42, p = 0.0003) but not long-term monitoring (p > 0.05). Bisphosphonate use was also shown to significantly reduce the likelihood of postoperative vertebral compression fracture (VCF; OR 0.07, 95% CI 0.01-0.59, p = 0.01) and significantly reduce Oswestry Disability Index scores (mean difference [MD] = -2.19, 95% CI -2.94 to -1.44, p < 0.00001) and visual analog scale pain scores (MD = -0.58, 95% CI -0.79 to -0.38, p < 0.00001). Teriparatide was found to significantly increase fusion rates at long-term postoperative periods as compared to rates after bisphosphonate therapy, with patients who received postoperative teriparatide therapy 2.05 times more likely to experience successful fusion (OR 2.05, 95% CI 1.17-3.59, p = 0.01). CONCLUSIONS: The authors demonstrate the benefits of bisphosphonate and teriparatide therapy independently in accelerating fusion during the first 6 months after spinal fusion surgery in osteoporotic patients. In addition, they show that teriparatide may have superior benefits in spinal fusion during long-term monitoring as compared to those with bisphosphonates. Bisphosphonates may be better suited in preventing VCFs postoperatively in addition to minimizing postoperative disability and pain.

Indeterminate Cell Histiocytosis of the Spine: A Case Report.

INTRODUCTION: Indeterminate cell histiocytosis is a rare neoplastic disease characterized by proliferation of dendritic cells that share morphologic and immunophenotypic features of Langerhans cells and non-Langerhans histiocytes. ICH lesions are typically restricted to the skin; however, there have been rare reports of extracutaneous and systemic involvement. CASE PRESENTATION: We describe a case of a 13-year-old female presenting with complaints of worsening lower back pain for 1 year. CT and MRI of the lumbar spine demonstrated a well-defined bony, lytic, expansile lesion of the posterior and mid-endplate of the L4 vertebra with mass effect on the thecal sac. The patient underwent L3-L5 decompression and fusion with surgical excision of the vertebral body tumor. Microscopic examination of the lesion showed benign fibrohistiocytic proliferation with giant cells, and immunohistochemical staining revealed a phenotype consistent with indeterminate cell histiocytosis (S100+ CD1a+ langerin-). DISCUSSION/CONCLUSION: ICH is an extraordinarily rare neoplastic disease of dendritic cells that has a poorly understood pathogenesis. This case expands the spectrum of potential ICH extracutaneous involvement to now include the spine, a location previously undocumented in the literature in the pediatric population.

Secure Combination of IoT and Blockchain by Physically Binding IoT Devices to Smart Non-Fungible Tokens Using PUFs.

Non-fungible tokens (NFTs) are widely used in blockchain to represent unique and non-interchangeable assets. Current NFTs allow representing assets by a unique identifier, as a possession of an owner. The novelty introduced in this paper is the proposal of smart NFTs to represent IoT devices, which are physical smart assets. Hence, they are also identified as the utility of a user, they have a blockchain account (BCA) address to participate actively in the blockchain transactions, they can establish secure communication channels with owners and users, and they operate dynamically with several modes associated with their token states. A smart NFT is physically bound to its IoT device thanks to the use of a physical unclonable function (PUF) that allows recovering its private key and, then, its BCA address. The link between tokens and devices is difficult to break and can be traced during their lifetime, because devices execute a secure boot and carry out mutual authentication processes with new owners and users that could add new software. Hence, devices prove their trusted hardware and software. A whole demonstration of the proposal developed with ESP32-based IoT devices and Ethereum blockchain is presented, using the SRAM of the ESP32 microcontroller as the PUF.

Preoperative SPECT imaging as a tool for surgical planning in patients with axial neck and back pain.

OBJECTIVE: Hybrid SPECT with CT imaging has been used to help elucidate pain generators in patients with axial neck and back pain, identifying potential sites for treatment. Few studies have examined its role in spine surgery and most literature focuses on its use postoperatively. The authors describe the largest series to date of patients with symptomatic spondylosis who underwent preoperative SPECT imaging for surgical planning. METHODS: A retrospective medical and imaging record review was conducted to identify patients who underwent SPECT or SPECT/CT studies between January 2014 and May 2018. Patients who underwent spine surgical intervention for spondylosis with primary symptoms of axial neck or back pain and who had evidence of hypermetabolic foci on spinal SPECT imaging were included. Only those patients who subsequently underwent surgery on a spinal level associated with increased radiotracer uptake were included in the analysis. Patient baseline and demographic information, and data pertaining to SPECT imaging, surgical planning, and postoperative care were collected and analyzed. RESULTS: A total of 23 patients with an average age at surgery of 60.0 ± 11.0 years were included. Fifteen patients (65.2%) were male. A total of 53 spinal levels were treated, with an average of 2.30 levels treated per patient. All patients underwent fusion surgery, either lumbar (n = 14), with interbody fusion most commonly used (64.2%); or cervical (n = 9), with anterior cervical discectomy and fusion (66.6%) being the most common. The average length of hospital stay was 3.45 ± 2.32 days. One patient developed a wound infection postoperatively, requiring readmission. At the 3-month follow-up, 18 patients (78.3%) reported clinical improvement in pain. Eleven patients (47.8%) reported complete symptom resolution at the 6-month follow-up. At 1 year postoperatively, 19 patients (82.6%) reported significant relief of their symptoms following surgery. CONCLUSIONS: This is the largest series to date describing patients with axial neck and back pain who underwent preoperative SPECT imaging and subsequent surgical intervention on the affected spinal levels. The results demonstrate that SPECT imaging may be a useful adjunct to guide surgical planning, resulting in substantial clinical improvement following surgery.

Obturator to Femoral Nerve Transfer: 2-Dimensional Operative Video.

Injury to the femoral nerve can cause femoral nerve palsy,1 resulting in severe ambulation difficulties and loss of sensory function in the anteromedial thigh and medial calf.2,3 Treatment options focus on nerve repair by direct coaptation, nerve grafting, or nerve transfer.3 If the proximal nerve stump is inaccessible, the location of nerve injury is at a distance from the site of muscle innervation, and/or there is a large nerve gap, nerve transfer may be a promising alternative treatment option.4-6 Nerve transfer uses only one coaptation site and allows for a faster recovery time due to a shorter nerve regeneration distance.2,3 A 32-year-old woman presented with persistent and severe proximal right lower extremity weakness after a right retroperitoneal femoral nerve schwannoma resection at an outside institution. After surgery, she reported that she could not flex her right hip or extend her right knee. MRI demonstrated a right femoral nerve gap defect (7.5 cm) at the schwannoma resection site. A right obturator to femoral nerve transfer was performed (see Video). 1.5-year follow-up visit showed that she had begun to have evidence of active recruitment of the right quadriceps muscle and started walking without a knee brace. 2.5-year follow-up visit showed improving strength (4-) in her right quadriceps muscle, independent walking for longer distances, and participation in sporting activities. The patient consented to the procedure, and the patients and any identifiable individuals consented to publication of his/her image. Institutional Review Board approval was not required for this single case observational surgical video.

The role of emboli detection studies in acute inpatient vertebral artery dissection.

BACKGROUND: Prompt diagnosis and treatment of vertebral artery dissection (VAD) is critical for preventing stroke. The use of emboli detection studies (EDS) using Doppler ultrasonography is an emerging method that has been proposed to predict stroke risk and guide subsequent treatment. Limited data exists on the predictive value of this emerging modality in the posterior circulation. This study aims to assess the predictive value of emboli detection studies (EDS) in forecasting inpatient stroke in VAD patients and identify associated risk factors. Patients were recruited between January 2009 and January 2018. METHODS: We performed a retrospective analysis of 104 consecutive patients with VAD who underwent EDS at our institution. Patients underwent transcranial ultrasonography for detection of microemboli and were followed clinically and radiographically thereafter for evidence of stroke. RESULTS: A total of 104 patients with spontaneous (58 %), traumatic (39 %) or iatrogenic (4 %) VAD were included in our analysis. Stroke occurred more frequently in patients with spontaneous VAD compared to traumatic VAD (p < 0.001). Microemboli were detected in 17 patients (16 %), including 18.3 % of spontaneous VAD, 12.5 % of traumatic VAD, and 25 % of iatrogenic VAD. 61 patients (59 %) suffered a posterior circulation stroke, however there was no significant association between detection of microemboli and stroke events (60 % of patients without microemboli vs. 53 % of patients with ≥ 1 HITS during EDS; p = 0.6). Similarly, no microemboli were detected in any of the patients who went on to develop a delayed stroke. CONCLUSIONS: In our single-institution retrospective analysis of patients with VAD, the detection of microemboli on EDS was not associated with stroke nor was it predictive of delayed stroke. Additionally, patients with spontaneous VAD may be at higher risk for stroke compared to traumatic VAD.

Effects of Obesity on Cervical Disc Arthroplasty Complications.

OBJECTIVE: High body mass index is a well-established modifiable comorbidity that is known to increase postoperative complications in all types of surgery, including spine surgery. Obesity is increasing in prevalence amongst the general population. As this growing population of obese patients ages, understanding how they faire undergoing cervical disc arthroplasty (CDA) is important for providing safe and effective evidence-based care for cervical degenerative pathology. METHODS: Our study used the Healthcare Cost and Utilization Project's National Inpatient Sample to assess patients undergoing CDA comparing patient characteristics and outcomes in nonobese patients to obese patients from 2004 to 2014. RESULTS: Our study found a significant increase in the overall utilization of CDA as a treatment modality (p = 0.012) and a statistically significant increase in obese patients undergoing CDA (p < 0.0001) from 2004 to 2014. Obesity was identified as an independent risk factor associated with increased rates of inpatient neurologic complications (odds ratio [OR], 6.99; p = 0.03), pulmonary embolus (OR, 5.41; p = 0.05), and wound infection (OR, 6.97; p < 0.001) in patients undergoing CDA from 2004 to 2014. CONCLUSION: In patients undergoing CDA, from 2004 to 2014, obesity was identified as an independent risk factor with significantly increased rates of inpatient neurologic complications, pulmonary embolus and wound infection. Large prospective trials are needed to validate these findings.

The Use of Carbon Fiber-Reinforced Instrumentation in Patients with Spinal Oncologic Tumors: A Systematic Review of Literature and Future Directions.

INTRODUCTION: Metastatic spine tumors affect over 30% of patients who have been diagnosed with cancer. While techniques in surgical intervention have undoubtedly evolved, there are some pitfalls when spinal instrumentation is required for stabilization following tumor resection. However, the use of carbon fiber-reinforced polyetheretherketone (CFR-PEEK) implants has become increasingly popular due to improved radiolucency and positive osteobiologic properties. Here, we present a systematic review describing the use of CFR-PEEK-coated instrumentation in the oncologic population while identifying advantages and potential shortcomings of these devices. METHODS: In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was conducted in March 2022 to identify articles detailing the use of CFR-PEEK implants for spinal instrumentation in patients with primary and secondary spine tumors. The search was performed using the PubMed, Scopus, and Embase databases. RESULTS: An initial search returned a total of 85 articles among the three databases used. After the exclusion of duplicates and screening of abstracts, 21 full-text articles were examined for eligibility. Eleven articles were excluded due to not fitting our inclusion and exclusion criteria. Ten articles were subsequently eligible for full-text review. CONCLUSIONS: CFR-PEEK possesses a similar safety and efficacy profile to titanium implants but has distinct advantages. It limits artifact, increases early detection of local tumor recurrence, increases radiotherapy dose accuracy, and is associated with low complication rates (9.96%)-making it a promising alternative for the demands unique to the treatment/outcome of spinal oncologic patients.

ORION software tool for the geometrical calibration of all-sky cameras.

This paper presents the software application ORION (All-sky camera geOmetry calibRation from star positIONs). This software has been developed with the aim of providing geometrical calibration to all-sky cameras, i.e. assess which sky coordinates (zenith and azimuth angles) correspond to each camera pixel. It is useful to locate bodies over the celestial vault, like stars and planets, in the camera images. The user needs to feed ORION with a set of cloud-free sky images captured at night-time for obtaining the calibration matrices. ORION searches the position of various stars in the sky images. This search can be automatic or manual. The sky coordinates of the stars and the corresponding pixel positions in the camera images are used together to determine the calibration matrices. The calibration is based on three parameters: the pixel position of the sky zenith in the image; the shift angle of the azimuth viewed by the camera with respect to the real North; and the relationship between the sky zenith angle and the pixel radial distance regards to the sky zenith in the image. In addition, ORION includes other features to facilitate its use, such as the check of the accuracy of the calibration. An example of ORION application is shown, obtaining the calibration matrices for a set of images and studying the accuracy of the calibration to predict a star position. Accuracy is about 9.0 arcmin for the analyzed example using a camera with average resolution of 5.4 arcmin/pixel (about 1.7 pixels).

Endoscopic decompression for the treatment of lumbar spinal stenosis: an updated systematic review and meta-analysis.

OBJECTIVE: Lumbar stenosis treatment has evolved with the introduction of minimally invasive surgery (MIS) techniques. Endoscopic methods take the concepts applied to MIS a step further, with multiple studies showing that endoscopic techniques have outcomes that are similar to those of more traditional approaches. The aim of this study was to perform an updated meta-analysis and systematic review of studies comparing the outcomes between endoscopic (uni- and biportal) and microscopic techniques for the treatment of lumbar stenosis. METHODS: Following PRISMA guidelines, a systematic search was performed using the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Ovid Embase, and PubMed databases from their dates of inception to December 14, 2020. All identified articles were then systematically screened against the following inclusion criteria: 1) studies comparing endoscopic (either uniportal or biportal) with minimally invasive approaches, 2) patient age ≥ 18 years, and 3) diagnosis of lumbar spinal stenosis. Bias was assessed using quality assessment criteria and funnel plots. Meta-analysis using a random-effects model was used to synthesize the metadata. RESULTS: From a total of 470 studies, 14 underwent full-text assessment. Of these 14 studies, 13 comparative studies were included for quantitative analysis, totaling 1406 procedures satisfying all criteria for selection. Regarding postoperative back pain, 9 studies showed that endoscopic methods resulted in significantly lower pain scores compared with MIS (mean difference [MD] -1.0, 95% CI -1.6 to -0.4, p < 0.01). The length of stay data were reported by 7 studies, with endoscopic methods associated with a significantly shorter length of stay versus the MIS technique (MD -2.1 days, 95% CI -2.7 to -1.4, p < 0.01). There was no significant difference with respect to leg visual analog scale scores, Oswestry Disability Index scores, blood loss, surgical time, and complications, and there were not any significant quality or bias concerns. CONCLUSIONS: Both endoscopic and MIS techniques are safe and effective methods for treating patients with symptomatic lumbar stenosis. Patients who undergo endoscopic surgery seem to report less postoperative low-back pain and significantly reduced hospital stay with a trend toward less perioperative blood loss. Future large prospective randomized trials are needed to confirm the findings in this study.

The declining incidence of cervical spine surgery in patients with rheumatoid arthritis: a single-surgeon series and literature review.

OBJECTIVE: With an increasing number of disease-modifying drugs available to manage rheumatoid arthritis (RA), spine surgeons have anecdotally noted decreased rates of cervical spine surgical procedures in this population. Although these medications have been shown to mitigate RA progression and its systemic effects on joint destruction, there are currently no large-scale studies of RA patients that suggest the use of these disease-modifying drugs has truly coincided with a decline in cervical spine surgery. METHODS: Patients with RA who underwent cervical spinal fusion from 1998 to 2021 performed by the senior author were retrospectively reviewed. The cohort was stratified into 3 categories based on procedure level: 1) occipitocervical, 2) atlantoaxial, and 3) subaxial. The number of surgical procedures per year in each subgroup was evaluated to determine treatment trends over time. National (Nationwide) Inpatient Sample (NIS) data on both RA and non-RA patients who underwent cervical fusion were analyzed to assess for surgical trends over time and for differences in likelihood of surgical intervention between RA and non-RA patients over the epoch. RESULTS: From 1998 to 2021, the number of overall cervical fusions performed in RA patients significantly declined (-0.13 procedures/year, p = 0.01) in this cohort, despite an overall significant increase in cervical fusions in non-RA patients over the same period. NIS analysis of cervical fusions across all patients similarly demonstrated a significant increase in cervical fusions over the same epoch (19,278 cases/year, p < 0.0001). When normalized for changes in population size, the incidence of new surgical procedures was lower in patients with RA regardless of surgical technique. Anterior cervical fusion was the most common approach used over the epoch in both RA and non-RA patients; correspondingly, RA patients were significantly less likely to undergo anterior cervical fusion (OR 0.655, 95% CI -0.4504 to -0.3972, p < 0.0001). CONCLUSIONS: At the authors' institution, there was a clear decline in the number of cervical fusions performed to treat the 3 most common forms of cervical spine pathology in RA patients (basilar impression, atlantoaxial instability, and subaxial cervical deformity). Although national trends suggest an increase in total cervical fusions in both RA and non-RA patients, the incidence of new procedures in patients with RA was significantly lower than in patients without RA, which supports the anecdotal results of spine surgeons nationally.

Use of an External Ventricular Drain for Treatment of a Thoracolumbar Cerebrospinal Fluid Leak: A Case Report and Review of Literature.

Post-operative cerebrospinal fluid (CSF) leak is a known complication in spine surgery. This mostly iatrogenic issue is typically treated using a variety of modalities (i.e., bed rest, epidural patch), CSF diversion methods, or primary repair. The use of an external ventricular drain to treat this post-operative complication has been infrequently reported. We describe a case of a CSF leak after thoraco-lumbar surgery treated using an external ventricular drain and a review of the literature regarding this treatment modality. A 70-year-old man presented to our clinic with a recent diagnosis of multiple myeloma with progressive thoracic kyphosis and spinal stenosis. He developed progressive neurological deficits over the course of several weeks. Radiological studies showed significant thoracic kyphosis and severe cord compression in the thoraco-lumbar area. The patient underwent a T9-L4 posterior instrumentation and fusion with decompression surgery that developed post-operative wound infection and a CSF leak. An external ventricular drain (EVD) was used successfully as a CSF diversion method where direct thoracolumbar approaches were not feasible. Given the effectiveness of EVD placement in treating this post-operative complication, we concluded that the use of an EVD can be a potentially safe and effective way to treat thoracolumbar CSF leakage when lumbar or cervical drainage is not feasible.

Size matters - From the working channel to the wavelength of light: Optimizing visualization in endoscopic spine surgery.

BACKGROUND: Minimally invasive surgery bases many of its benefits on decreasing tissue disruption. Endoscopic spine surgery has continued to push the boundaries to accomplish successful clinical outcomes through the evolution of the endoscope and working channel. As the indications for endoscopic spine surgery increase, a more profound discussion of cannula size selection for endoscopic spine surgery is required. The intimate relationship between the working channel, the endoscope and how these choices affect workflow and visualization are paramount to maximize outcomes. METHODS: The authors review the nuances of the endoscopic approaches to the various regions of the spine as it relates to the selection of the working channel. The advantages and limitations of various endoscopic working channels were analyzed as to how they address anatomic regional considerations as well as ultimate goals of surgery. RESULTS: In addition to anatomic regional differences and the goals of the surgery other key elements in endoscopic working channel selection included the amount of tissue disruption, regional risk to the neural elements, impact on visualization, optical physics, and the implications for surgical maneuverability/dexterity. CONCLUSION: Understanding the role and use of the endoscope-working channel combination with its effects on visualization is essential for any surgeon aspiring to perform safe and efficient full endoscopic spine surgery.