Search

Symptomatic lumbar spinal stenosis (LSS) is a common indication for surgery in the elderly. Preoperative radiographic evaluation of patients with LSS often reveals redundant nerve roots (RNRs). The clinical significance of RNRs is uncertain. RNRs have not been studied in the setting of minimally invasive surgery. This study investigates the relationship between RNRs and clinical outcomes after minimally invasive tubular decompression.Chart review was performed for patients with degenerative LSS who underwent minimally invasive decompression. Preoperative magnetic resonance imaging parameters were assessed, and patient-reported outcomes were analyzed.Fifty-four patients underwent surgery performed at an average of 1.8 ± 0.8 spinal levels. Thirty-one patients (57%) had RNRs. Patients with RNRs were older (median = 72 years vs. 66 years, P = 0.050), had longer median symptom duration (32 months vs. 15 months, P 0.01), and had more levels operated on (2.1 vs. 1.4; P 0.01). The median follow-up after surgery was 2 months (range = 1.3-12 months). Preoperative and postoperative patient-reported outcomes were similar based on RNR presence. Patients without RNRs had larger lumbar cross-sectional areas (CSAs) (median = 121 mmPreoperative RNRs are associated with increased age, symptom duration, and lumbar stenosis severity. Patients improved after minimally invasive decompression regardless of RNR presence. RNR presence had no effect on short-term clinical outcomes. Further study is required to assess their long-term significance.

The objective of this study is to provide an update on endovascular treatments for iatrogenic internal carotid artery (ICA) injuries following endonasal surgery. A systematic review of the literature was performed by using Medline, Cochrane library, and Scopus from 1999 to 2019. We used a combination of the MeSH terms “internal carotid artery,” “iatrogenic disease,” and “endovascular procedure.” Twenty-six articles including 46 patients were identified for in this systematic review. The mean age of the patients was 49 years (CI: ± 4.2). The most common site of ICA injury was in cavernous segment (18 patients; 39%). The most common type of iatrogenic ICA injury was a traumatic pseudoaneurysm documented in 28 patients (60%). Endoluminal reconstruction was performed using covered stents in 28 patients, the Pipeline embolization device (PED) in 13 patients, the Surpass flow diverter device in three, the SILK flow diverter in one, and one case was treated using a combined approach of a covered stent and a PED. Flow diversion and covered stents resulted in a good clinical outcome in 94% and 89% of patients, respectively. This difference did not reach statistical significance (p = 1.0). Even though this systematic review was limited due to articles of small sample sizes and considerable heterogeneity, the results indicate that flow diverting devices and covered stents are good therapeutic options for endoluminal reconstruction of iatrogenic ICA injuries following endonasal surgery.

This paper provides a detailed report of Global Neurosurgery 2019: A Practical Symposium held January 18-19, 2019, at Weill Cornell Medical College, New York, New York, USA. The meeting convened an international faculty and audience, leaders in the world of global neurosurgery (GNS), and junior faculty and residents beginning their contribution to the field. Remote access for the symposium was provided to include faculty practicing in developing countries. The goal of the symposium was to present the state of the union of GNS initiatives worldwide, to use this forum as a means to centralize resources and converge parallel efforts, and to identify the largest areas of need and successful means of advancing training and care in these areas. The meeting also served as a conduit for the presentation of funding and training opportunities for junior faculty and trainees looking for avenues to gain support and mentorship in pursuing academic and clinical endeavors globally.

Study Design:Systematic review.Objective:To date there is no consensus among surgeons as to what defines an MIS-TLIF (transforaminal lumbar interbody fusion using minimally invasive spine surgery) compared to an open or mini-open TLIF. This systematic review aimed to examine the MIS-TLIF techniques reported in the recent body of literature to help provide a definition of what constitutes the MIS-TLIF, based on the consensus of the majority of surgeons.Methods:We created a database of articles published about MIS-TLIF between 2010 and 2018. We evaluated the technical components of the MIS-TLIF including instruments and incisions used as well the order in which key steps are performed.Results:We could identify several patterns for MIS-TLIF performance that seemed agreed upon by the majority of MIS surgeons: use of paramedian incisions; use of a tubular retractor to perform a total facetectomy, decompression, and interbody cage implantation; and percutaneous insertion of the pedicle-screw rod constructs with intraoperative imaging.Conclusion:Based on this review of the literature, the key features used by surgeons performing MIS TLIF include the use of nonexpandable or expandable tubular retractors, a paramedian or lateral incision, and the use of a microscope or endoscope for visualization. Approaches using expandable nontubular retractors, those that require extensive subperiosteal dissection from the midline laterally, or specular-based retractors with wide pedicle to pedicle exposure are far less likely to be promoted as an MIS-based approach. A definition is necessary to improve the communication among spine surgeons in research as well as patient education.

Innovative technology and techniques have revolutionized minimally invasive spine surgery (MIS) within the past decade. The introduction of navigation and image-guided surgery has greatly affected spinal surgery and will continue to make surgery safer and more efficient. Eventually, it is conceivable that fluoroscopy will be completely replaced with image guidance. These advancements, among others such as robotics and virtual and augmented reality technology, will continue to drive the value of 3-dimensional navigation in MIS. In this review, we cover pertinent features of navigation in MIS and explore their evolution over time. Moreover, we aim to discuss the key features germane to surgical advancement, including technique and technology development, accuracy, overall health care costs, operating room time efficiency, and radiation exposure.

Study Design: A retrospective single-center analysis of 159 cases. Objective: To investigate differences between male and female patients, as spinal infection (SI) represents a life-threatening condition and numerous factors may facilitate the course and outcome of SI, including patients’ age and comorbidities, as well as gender. To date, no comparative data investigating sex differences in SI is available. Thus, the purpose of the present retrospective trial was to investigate differences between male and female patients. Methods: A total of 159 patients who were treated for a spinal infection between 2010 and 2016 at our department were included in the analysis. The patients were categorized into 2 groups based on gender. Evaluation included magnetic resonance imaging, laboratory values, clinical outcome, and conservative/operative management. Results: Male patients suffered from SI significantly more often than female patients (n = 101, 63.5% vs n = 58, 36.5%, P = .001). However, female patients were initially affected more severely, as infection parameters were significantly higher ( P = .032) and vertebral destruction was more serious ( P = .018). Furthermore, women suffered from intraoperative complications more often ( P = .024) and received erythrocyte concentrates more frequently ( P = .01). Nevertheless, mortality rates and outcome were comparable. Pain scales were significantly higher in female patients at 12-month follow-up ( P = .042). Conclusion: Although male patients show a higher incidence for SI, the course of disease and the management is more challenging in female patients. Nevertheless, outcome after 12 months is comparably good. Underlying mechanisms may include a better immune response and dissimilar effects of antibiotic treatment in women. Pain management in female patients is still unsatisfactory after 12 months.

Background Direct carotid cavernous fistulas (CCFs) and sphenoid sinus traumatic aneurysms are well-known pathologies that can present concomitantly in rare cases. Patients with both lesions are usually symptomatic from both the CCF and the traumatic aneurysm. Symptoms include proptosis, chemosis, bruit, epistaxis, visual field defects, and loss of vision. Surgical treatment can be challenging, and for most cases an endovascular approach is the treatment of choice. Case Description We present an unusual case of a direct CCF with an associated large traumatic aneurysm in the sphenoid sinus due to a history of trauma presenting with unusual symptoms that was treated by a combined endoscopic and endovascular approach. Conclusions Concurrent occurrence of a traumatic CCF and traumatic aneurysm of the cavernous segment is extremely rare. Early diagnosis and treatment of these lesions are important considering their high mortality rate. Complete occlusion of the fistula and aneurysm while preserving the patency of the carotid artery via an endovascular approach is the treatment of choice for these lesions.

Purpose Approaches for lumbar corpectomies can be roughly categorized into anterolateral (AL) and posterolateral (PL) approaches. It remains controversial to date whether one approach is superior to the other, and no comparative studies exist for the two approaches for lumbar corpectomies. Methods A systematic review of the literature was performed through a MEDLINE/PubMed search. Studies and case reports describing technique plus outcomes and possible complications were included. Thereafter, estimated blood loss (EBL), length of operation (LOO), utilized implants, neurological outcomes, complication rates, and reoperation rates were analyzed. Results A total of 64 articles reporting on 702 patients including 513 AL and 189 PL corpectomies were included in this paper. All patients in the PL group were instrumented via the same approach used for corpectomy, while in the AL group the majority (68.3%) of authors described the use of an additional approach for instrumentation. The EBL was higher in the AL group (1393 ± 1341 ml vs. 982 ± 567 ml). The LOO also was higher in the AL group (317 ± 178 min vs. 258 ± 93 min). The complication rate (20.5% vs. 29.1%, p = 0.048) and the revision rate (3.1% vs. 9.5%, p = 0.004) were higher in the PL group. Neurological improvement rates were 43.8% (AL) vs. 39.2% (PL), and deterioration was only noted in the AL group (6.0%), while 50.2% (AL) and 60.8% (PL) showed no change from initial presentation to the last follow-up. Conclusion While neurological outcomes of both approaches are comparable, the results of the present review demonstrated lower complication and revision rates in anterolateral corpectomies. Nevertheless, individual patient characteristics must be considered in decision-making.

Intervertebral disc (IVD) herniations are currently treated with interventions that leave the IVD with persistent lesions prone to further herniations. Annulus fibrosus (AF) repair has become of interest as a method to seal defects in the IVD and prevent reherniation, but this requires strong adhesion of the implanted biomaterial to the native AF tissue. Our group has previously developed a high-density collagen (HDC) gel for AF repair and tested its efficacy in vivo, but its adhesion to the AF could be improved. Increased cell adhesion to cartilage has previously been reported through chondroitinase ABC (ChABC) digestion, which removes proteoglycans and increases access to cell binding motifs. Such approaches could also increase biomaterial adhesion to tissue, but the effects of ChABC digestion on AF have yet to be investigated. In this study, ovine AF tissue was digested with either 10 U/mL ChABC or saline for up to 10 min and the effect of this treatment on collagen adhesion between AF tissue samples was investigated by histology and mechanical testing in a lap-shear configuration. ChABC digestion removed proteoglycans within the AF in a time-dependent fashion and enhanced adhesion of the HDC gel to the AF. ChABC digestion increased the elastic toughness and total shear energy of the HDC gel-AF interface by 88% and 46% respectively. ChABC treatment enhanced the adhesion of the HDC gel to the AF without significantly decreasing native AF cell viability. Thus, ChABC digestion is a viable method to improve adhesion of biomaterials for AF repair. Statement of Significance Intervertebral disc herniations are currently treated with interventions that leave persistent lesions in the annulus fibrosus that are prone to further herniations. Annular repair is a promising method to seal lesions and prevent reherniation, but requires strong adhesion of the implanted biomaterial to native annulus fibrosus. Since large proteoglycans like aggrecan occupy regions of the extracellular matrix between collagen fibers in the annulus fibrosus, we hypothesized that removing proteoglycans via chondroitinase digestion would increase the adhesion of annular repair hydrogels. This investigation demonstrated that chondroitinase removed proteoglycans within annulus fibrosus tissue, enhanced the interaction of an injected collagen gel with the native tissue, and mechanically improved adhesion between the collagen gel and annulus fibrosus. This is the first study of its kind to evaluate the biochemical and mechanical effects of short-term chondroitinase digestion on annulus fibrosus tissue.

The negative impact on spinal diseases may apply not only to obesity but also to smoking. To investigate the influence of obesity and smoking on the development and recovery of lumbar disc herniation in young adults. Retrospective analysis of 97 patients who presented with lumbar disc herniation at the authors’ department between 2010 and 2017. Data were collected using the patients’ digital health records including demographics, clinical and neurological characteristics, treatment details, and outcomes. Ninety-seven patients between 17 and 25 years were included in this retrospective analysis. Patients were categorized into two groups according to their body mass index: obese (O, ≥ 30 kg/m2) and non-obese (NO, 2). The proportion of obese patients in our cohort vs. in the overall population differed significantly (19.4% vs. 3.8–7.1%, RR 3.17; p p = 0.067) and pain (p = 0.074). Also, the proportion of regular smokers differed significantly from the numbers of known smokers of the same age (62.4% vs. 30.2%, RR 2.0; p = 0.01). Obesity plus smoking showed a significantly negative impact on motor deficits postoperatively (p = 0.015) and at discharge (p = 0.025), as well as on pain values (p = 0.037) and on analgesic consumption (p = 0.034) at 6 weeks follow-up. The negative impact of obesity and smoking on the occurrence of lumbar disc herniation could be demonstrated for individuals aged 25 or younger. Furthermore, a trend to earlier recovery of motor deficits and significantly lower pain scales for non-obese and non-smoking patients could be shown.

The unilateral laminotomy for bilateral decompression initially was described in the late 1990s and has evolved in conjunction with minimally invasive surgical instrumentation. This technique has been shown to significantly improve bilateral symptoms regardless of the side of approach. It also can be used for multilevel decompressions using the slalom technique with alternating lateralizing sites of access. The over-the-top technique involving a unilateral approach for bilateral decompression helps preserve the posterior tension band and can accomplish the operative goals with better clinical outcomes than traditional open approaches.

Background Pial arteriovenous fistulas are abnormal vascular connections between arteries and the cranial venous system on the surface of the brain in the pia mater. In contrast to vein of Galen aneurysmal malformations, they lack a true vascular nidus and may only indirectly involve the vein of Galen. Case Description An 18-month-old boy was referred to us with a history of seizures, drowsiness, bulging cephalic veins, and cranial nerves palsy identified as vein of Galen aneurysmal malformation according to initial magnetic resonance imaging. Digital subtraction angiography showed a vertebrobasilar junction pial high-flow fistula between the basilar artery and anterior pontomesencephalic vein, causing retrograde flow, dilation, and tortuosity of the lateral and posterior mesencephalic vein as well as the vein of Galen. Endovascular treatment, including coil embolization of fistula site, was done successfully without complication resulting in recovery from previous symptoms and signs. Conclusions If cerebral venous dilations are encountered, one must keep in mind that the location of the fistula may not be in close proximity to the dilated veins, especially when there is a suspicion for vein of Galen aneurysmal malformation. Other pathologies, such as pial arteriovenous fistula, in a region away from the site of the vein of Galen must be considered.

Background: For complex spinal cases, especially when robotic guidance is used, preoperative planning of pedicle screws can be helpful. Transfer of these preoperatively planned pedicle screws to intraoperative 3-dimensional imaging is challenging because of changes in anatomic alignment between preoperative supine and intraoperative prone imaging, especially when multiple levels are involved. In the spine, where each individual vertebra is subject to independent movement from adjacent level, rigid image fusion is confined to a single vertebra and can display fusion inaccuracies on adjacent levels. A novel elastic fusion algorithm is introduced to overcome these disadvantages. This study aimed to investigate image registration accuracy of preoperatively planned pedicle screws with an elastic fusion algorithm vs. rigid fusion for intraoperative placement with image-guided surgery. Methods: A total of 12 patients, were selected depending on the availability of a preoperative spinal computed tomography (CT) and an intraoperative AIRO CT scan (BrainLAB AG, Munich, Germany) of the same spinal region. To verify accuracy differences between rigid fusion and elastic fusion 76 bilateral screw trajectories were virtually defined in the preoperative CT image, and they were transferred via either rigid fusion or elastic fusion to the intraoperative CT scan. Accuracy of the transferred screws in the rigid and elastic fusion group was determined by measuring pedicle breaches on the intraoperative CT. Results: In the rigid fusion group 1.3% of screws showed a breach of less than 2 mm, 9.2% showed breaches between 2 and 4 mm, and 18.4% of the screws showed an error above 4 mm. The elastic fusion group showed no breaches and provided high accuracy between preoperative and intraoperative screw placement. Conclusion: Elastic fusion provides high registration accuracy and represents a considerable step towards efficiency and safety in CT-based image-guided surgery. Level of Evidence: 3.

Due to advances in interventional techniques, the transvenous approach may present an effective treatment option for embolization of brain arteriovenous malformations (AVMs). Contrary to the transarterial method, the transvenous approach can only be utilized in a specific subset of patients and is not suitable as a standard procedure for all AVM lesions. While this technique can be helpful in certain patients, careful patient selection to ensure patient safety and favorable clinical outcomes is important. However, especially in high-flow AVMs, targeted deposition of embolic materials through a transvenous access can be challenging. Therefore, a temporary flow arrest may prove helpful. Transient cardiac arrest by use of adenosine has been applied in cerebrovascular surgery but is not common for endovascular embolization. Adenosine-induced arrest and systemic hypotension may be a feasible, safe method to reduce flow and help endovascular transvenous embolization of certain AVMs. Our study evaluated the efficiency and safety of adenosine-induced circulatory arrest for transvenous embolization of cerebral AVMs.

Study Design: Prospective case series. Objective: SSPSS (single step pedicle screw system) was developed for minimally invasive spine surgery. We performed this study to report on safety, workflow, and our initial clinical experience with this novel technique. Methods: The prospective study was conducted on patients who underwent pedicle screw fixation between October 2017 and April 2018 using a novel single step 3D navigated pedicle screw system for MIS. Outcome measurements were obtained from intraoperative computerized tomography. The images were evaluated to determine pedicle wall penetration. We used a grading system to assess the severity of the pedicle wall penetration. Breaches were classified as grade 1 ( 1 and as cranial, caudal, medial, and lateral. Results: Our study includes 135 screws in 24 patients. SSPSS eliminated K-wires and multiple steps traditionally necessary for MIS pedicle screw insertion. The median time per screw was 2.45 minutes. 3 screws were corrected intraoperatively. Pedicle wall penetration occurred in 14 screws (10%). Grade 1 breaches occurred in 4 screws (3%) and grade 2 breaches occurred in 10 screws (7%). Lateral breaches were observed more often than medial breaches. The accuracy rate in our study was 90% (Grade 0 breach). No revision surgeries were needed and no complications occurred. Conclusions: Our study suggests that SSPSS could be a safe, accurate, and efficient tool. Our accuracy rate is comparable to that found in the literature.

Background Inferior petrosal sinus sampling (IPSS) is known as the gold standard to distinguish whether excessive adrenocorticotropin hormone (ACTH) production origins from the pituitary gland or an ectopic source. However, due to a number of factors, the value of IPSS for adenoma lateralization may be limited. Aim of this study was to evaluate the influence of parasellar venous drainage (VD) patterns on IPSS findings in predicting lateralization of pituitary microadenomas. Methods We retrospectively reviewed records of confirmed cases of Cushing's disease which were evaluated by IPSS prior to endoscopic tansnasal trans-sphenoidal surgery (ETSS) to assess the ability of IPSS to predict adenoma laterality. Results Seventeen patients with pathologically confirmed Cushing's disease were retrospectively reviewed. The median age of the included patients was 37 years. Laterality of parasellar VD perfectly associated with lateralization as measured by IPSS. Symmetrical VD was associated with symmetrical ACTH gradient on IPSS. However, lateralization measured by IPSS did not show any significant correlation with lateralization detected during ETSS. Conclusion Our study suggests that IPSS lateralization results strongly depend on parasellar VD pattern but show no significant correlation with the adenoma lateralization found during ETSS. Thus, IPSS does not appear to be an appropriate modality to predict adenoma lateralization., Anatomy; Neurology; Medical imaging; Endocrinology; Endocrine system; Clinical research; Inferior petrosal sinus sampling; Cushing's disease; Parasellar venous drainage; Lateralization of microadenoma

Objective The middle cerebral artery (MCA) is the third most common site for ruptured intracranial aneurysms. Aneurysms in this location are known to be challenging to treat endovascularly and are commonly treated with microsurgery. Although advances in endovascular treatment options for cerebral aneurysms have markedly reduced the need for surgery in recent years and decades, there is no compelling scientific evidence that endovascular treatments are superior to surgical treatment. The present study aimed to determine the appropriate treatment modality in ruptured MCA aneurysms. Methods We retrospectively evaluated and compared the treatment outcomes of 80 patients with ruptured MCA aneurysms who underwent either endovascular or microsurgical treatment in our center between 2011 and 2016. Post-treatment clinical and radiological outcomes were assessed in all patients. Furthermore, we compared intraoperative complications and the need for re-treatments between the two groups. Results According to our findings, complete aneurysm occlusion was achieved in 90.5% and 89.2% of the patients in the clipping and coil group, respectively (p = 0.850). Moreover, 14.3% of the patients in the clipping group and 15.8% of the subjects in the coil group developed intraoperative complications (p = 0.851), including 3 cases of intraoperative hemorrhage and 3 cases of ischemia in the clipping group as well as 2 cases of thromboembolism and 4 cases of vasospasm during endovascular treatment in the coil group. There was an improvement in the modified Rankin score (mRS) at six months, with no significant difference between the two groups (p = 0.916). Conclusion The results of coiling only with coil able MCA aneurysms were comparable to the results of clipping with difficult cases. Sufficient follow-up study of recurrence and retreatment are needed to determine the indication for coiling for ruptured MCA aneurysm.

Introduction Temporary artery occlusion (TAO) is commonly used to facilitate dissection and clipping of intracranial aneurysms. When clipping anterior communicating artery (Acom) aneurysms, a possible strategy is to perform early preventive TAO of the contralateral A1 segment of the anterior cerebral artery before dissecting towards the aneurysm. In case of intraoperative complications such as complicated aneurysm dome preparation or inadvertent rupture of the aneurysm, full proximal control can be quickly gained by additional TAO of the easily accessible ipsilateral A1. Also, right-sided approaches are sometimes preferred due to reduced risk of damage of the dominant hemisphere and right-handedness of the surgeon. However, this may lead to prolonged TAO times of the contralateral A1 and might involve the risk of cerebral ischemia, especially if the contralateral A1 is the dominant supplier. In the present study, we aimed to investigate the safety of this strategy. Methods We retrospectively analyzed the clinical and imaging outcomes of Acom aneurysms treated at our institution over a period of seven years by a right-sided frontotemporal approach. Temporary contralateral A1 occlusion early after opening of the chiasmatic cistern was defined as early TAO. We evaluated the total TAO time, A1 dominance, intraoperative rupture rates as well as postoperative mRS. The primary outcome parameter was postoperative ischemia determined on CT scans within 48 hours after surgery by a board-certified neuroradiologist. Results A total of 81 including 52 ruptured and 29 unruptured aneurysms were treated by microsurgical clipping over a period of seven years. In 48 patients (59%) early contralateral A1 TAO was performed for an average of 22±20 min and the majority of these cases (30 patients) harbored a dominant contralateral A1. Bilateral TAO was performed in 22 patients (27%) for 11±10 min. Intraoperative rupture occurred in 20 patients (25%) of which 10 received early TAO. Postoperatively, 5 patients showed postoperative ischemia (6%). Bilateral TAO as well as dominant early TAO showed no significant correlation with ischemia or worse post-operative mRS. However, patients with ischemia had a significantly longer overall TAO time (45±27 mins) than patients without (19±18 mins) (p=0.02). Conclusion In our patient population neither early TAO of the dominant A1 nor bilateral TAO appeared to have an increased risk for ischemia. However, prolonged TAO, regardless of which side should be avoided. Disclosures C. Wipplinger: None. F. Mrosk: None. S. Tulu: None. C. Preuss-Hernandez: None. W. Ho: None. A. Gorke: None. M. Ortler: None. O. Petr: None. C. Thome: None.

Background: In patients with symptomatic lumbar stenosis undergoing lateral transpsoas approach for lumbar interbody fusion (LLIF) surgery, it is not always clear when indirect decompression is sufficient in order to achieve symptom resolution. Indirect decompression failure (IDF), defined as “postoperative persistent symptoms of nerve compression with or without a second direct decompression surgery to reach adequate symptom resolution,” is not widely reported. This information, however, is critical to better understand the indications, the potential, and the limitations of indirect decompression. Objective: The purpose of this study was to systematically review the current literature on IDF after LLIF. Methods: A literature search was performed on PubMed. We included randomized controlled trials and prospective, retrospective, case-control studies, and case reports. Information on sample size, demographics, procedure, number and location of involved levels, follow-up time, and complications were extracted. Results: After applying the exclusion criteria, we included 9 of the 268 screened articles that reported failure. A total of 632 patients were screened in these articles and detailed information was provided. Average follow-up time was 21 months. Overall reported incidence of IDF was 9%. Conclusion: Failures of decompression via LLIF are inconsistently reported and the incidence is approximately 9%. IDF failure in LLIF may be underreported or misinterpreted as a complication. We propose to include the term “IDF” as described in this article to differentiate them from complications for future studies. A better understanding of why IDF occurs will allow surgeons to better plan surgical intervention and will avoid revision surgery.

Study Design: Technical note, retrospective case series. Objective: Lumbar stenosis can be effectively treated using tubular unilateral laminotomy for bilateral decompression (ULBD). For multilevel stenosis, a multilevel ULBD through separate, alternating crossover approaches has been described as the “slalom technique.” To increase efficacy, we introduced this approach with 2 microscopes simultaneously. Methods: We collected data on 13 patients, with multilevel lumbar stenosis, operated at our institution between 2015 and 2016 by the aforementioned technique. We assessed surgical time (ST), estimated blood loss (EBL), complications, and revision surgeries. Furthermore, we provide a stepwise instruction for performing the tandem microscopic slalom technique in a safe and efficient manner. Results: The mean age of the patients was 68 ± 8 years. The ST per level was 68 ± 19 minutes with an EBL per level of 39 ± 30 mL. We had no intraoperative complications and none of our patients required a revision surgery during a mean follow-up of 12 months. Conclusions: We have shown that this technique is feasible and can be performed safely for multisegmental lumbar spinal stenosis with minimal tissue trauma and low EBL. Furthermore, randomized controlled studies with a larger sample size may be necessary to drive any final conclusions.

Purpose Spinal infection (SI) is a life-threatening condition and treatment remains challenging. Numerous factors influence the outcome of SI and both conservative and operative care can be applied. As SI is associated with mortality rates between 2 and 20% even in developed countries, the purpose of the present study was to investigate the occurrence and causes of death in patients suffering from SI. Methods A retrospective analysis was performed on 197 patients, categorized into two groups according to their outcome: D (death) and S (survival). The diagnosis was based on clinical and imaging (MRI) findings. Data collected included demographics, clinical characteristics, comorbidities, infection parameters, treatment details, outcomes, and causes of death. Results The number of deaths was significantly higher in the conservative group (n = 9/51, 18%) compared with the operative counterpart (n = 8/146, 6%; p = 0.017). Death caused by septic multiorgan failure was the major cause of fatalities (n = 10/17, 59%) followed by death due to cardiopulmonary reasons (n = 4/17, 24%). The most frequent indication for conservative treatment in patients of group D included “highest perioperative risk” (n = 5/17, 29%). Conclusion We could demonstrate a significantly higher mortality rate in patients solely receiving conservative treatment. Mortality is associated with number and type of comorbidities, but also tends to be correlated with primarily acquired infection. As causes of death are predominantly associated with a septic patient state or progression of disease, our data may call for an earlier and more aggressive treatment. Nevertheless, prospective clinical trials will be mandatory to better understand the pathogenesis and course of spinal infection, and to develop high quality, evidence-based treatment recommendations.

The objective of this study is to provide an update on endovascular treatments for iatrogenic internal carotid artery (ICA) injuries following endonasal surgery. A systematic review of the literature was performed by using Medline, Cochrane library, and Scopus from 1999 to 2019. We used a combination of the MeSH terms "internal carotid artery," "iatrogenic disease," and "endovascular procedure." Twenty-six articles including 46 patients were identified for in this systematic review. The mean age of the patients was 49 years (CI: ± 4.2). The most common site of ICA injury was in cavernous segment (18 patients; 39%). The most common type of iatrogenic ICA injury was a traumatic pseudoaneurysm documented in 28 patients (60%). Endoluminal reconstruction was performed using covered stents in 28 patients, the Pipeline embolization device (PED) in 13 patients, the Surpass flow diverter device in three, the SILK flow diverter in one, and one case was treated using a combined approach of a covered stent and a PED. Flow diversion and covered stents resulted in a good clinical outcome in 94% and 89% of patients, respectively. This difference did not reach statistical significance (p = 1.0). Even though this systematic review was limited due to articles of small sample sizes and considerable heterogeneity, the results indicate that flow diverting devices and covered stents are good therapeutic options for endoluminal reconstruction of iatrogenic ICA injuries following endonasal surgery.

Alterations to the biochemical composition of the intervertebral disc (IVD) are hallmarks of aging and degeneration. Methods to assess biochemical content, such as histology, immunohistochemistry, and spectrophotometric assays, are limited in their ability to quantitatively analyze the spatial distribution of biochemical components. Fourier transform infrared (FTIR) microscopy is a biochemical analysis method that can yield both quantitative and high‐resolution data about the spatial distribution of biochemical components. This technique has been largely unexplored for use with the IVD, and existing methods use complex analytical techniques that make results difficult to interpret. The objective of the present study is to describe an FTIR microscopy method that has been optimized for imaging the collagen and proteoglycan content of the IVD. The method was performed on intact and discectomized IVDs from the sheep lumbar spine after 6 weeks in vivo in order to validate FTIR microscopy in healthy and degenerated IVDs. FTIR microscopy quantified collagen and proteoglycan content across the entire IVD and showed local changes in biochemical content after discectomy that were not observed with traditional histological methods. Changes in collagen and proteoglycans content were found to have strong correlations with Pfirrmann grades of degeneration. This study demonstrates how FTIR microscopy is a valuable research tool that can be used to quantitatively assess the local biochemical composition of IVDs in development, degeneration, and repair., In this study, we present a method for quantitatively assessing the spatial distribution of biochemical contents within the intervertebral disc using Fourier transform infrared (FTIR) microscopy. FTIR microscopy quantified collagen and proteoglycan content across the entire IVD and showed local changes in biochemical content after discectomy that were not observed with traditional histological methods. This study demonstrates how FTIR microscopy is a valuable research tool that can be used to quantitatively assess the local biochemical composition of IVDs in development, degeneration, and repair.

BACKGROUND Our group has previously demonstrated in vivo annulus fibrosus repair in animal models using an acellular, riboflavin crosslinked, high-density collagen (HDC) gel. OBJECTIVE To assess if seeding allogenic mesenchymal stem cells (MSCs) into this gel yields improved histological and radiographic benefits in an in vivo sheep model of annular injury. METHODS Fifteen lumbar intervertebral discs (IVDs) were randomized into 4 groups: intact, injury only, injury + acellular gel treatment, or injury + MSC-seeded gel treatment. Sheep were sacrificed at 6 wk. Disc height index (DHI), Pfirrmann grade, nucleus pulposus area, and T2 relaxation time (T2-RT) were calculated for each IVD and standardized to healthy controls from the same sheep. Quantitative histological assessment was also performed using the Han scoring system. RESULTS All treated IVDs retained gel plugs on gross assessment and there were no adverse perioperative complications. The MSC-seeded gel treatment group demonstrated statistically significant improvement over other experimental groups in DHI (P = .002), Pfirrmann grade (P

Background Superficial siderosis of the central nervous system is a rare neurologic disorder characterized by the superficial deposition of hemosiderin in the subpial layer resulting in iron-related progressive neurodegeneration. Case Description In this report, we present a case of superficial siderosis of the central nervous system secondary to an intradural thoracic disk herniation causing a cerebrospinal fluid (CSF) leak. Conclusions The patient was successfully treated with T6-T8 transpedicular partial corpectomy, as well as diskectomy with decompression followed by watertight closure of the CSF leak. Intraoperative watertight closure of the CSF leak was achieved.

Thoracic myelopathy is often caused by vertebral body fractures resulting from neoplastic conditions, traumatic events, or infectious diseases. One of the preferred procedures for treating it is the lateral extracavitary approach (LECA) with single-level or multilevel decompressive corpectomy and reconstruction. The aim of this retrospective study was to analyze the thoracic lateral extracavitary approach with corpectomy using vertebral body replacement systems (VBR-S) and dorsal reconstruction. Twenty-four patients with metastatic or primary lesions of thoracic vertebrae T2–T12 underwent spinal decompression and ventral column reconstruction with correction of spinal deformity via a LECA. One-level to four-level corpectomies were performed with additional navigated dorsal pedicle screw fixation at an average of two levels above and below the corpectomy lesion. None of the patients received preoperative spinal embolization, and the majority of the patients were admitted to radiotherapy postoperatively. Their mean age was 56 years (± 15), with a female-to-male sex ratio of 8 to 16. Patients with a minimum follow-up period of 16 months were included. The Karnofsky index, preoperative and postoperative numeric rating scale (NRS), and Frankel scale were measured. In addition, intraoperative loss of blood (LOB), units of packed red blood cell (PRBC) transfusions, the duration of the operation, and the hospitalization period were evaluated and correlated with preoperative and postoperative values. The majority of the patients were suffering from metastatic lesions and were treated with a 1 level corpectomy (median 1 level, range 1 to 4). The mean duration of surgery was 288 min (± 121) and the mean LOB was 1626 mL (± 1486 mL), with approximately two PRBC units per patient used. All patients were transferred to the intensive care unit (ICU) postoperatively, with a mean ICU stay of 2.0 days (± 1 day). The mean hospitalization period was 13 days (± 7 days). No implant-related failures or procedure-related deaths were observed. Significant differences were noted between the preoperative and postoperative Karnofsky index (74 vs. 84%) and NRS (4 vs. 2). One patient required revision surgery due to a superficial wound infection, and another needed revision surgery due to a dural tear. In another patient, an iatrogenic dural tear was repaired during the same surgical procedure and did not lead to postoperative complications. Four pleural effusions and one pneumothorax were observed, so that the overall complication rate was approximately 33%. Four of the patients died within 2 years of the operation due to progression of the primary disease. Lateral corpectomy and sagittal reconstruction of the thoracic spine using VBR-S conducted via a navigated LECA approach yields favorable results, despite the burden of neoplastic disease. These challenging procedures are accompanied by increased LOB and hospitalization periods, with moderate transfusion requirements. Surgery-related complications are low and local tumor control is satisfactory, despite the progression of the underlying neoplastic disease. However, optimal surgical therapy does not ensure long-term survival. Study design Retrospective analysis of thoracic corpectomies Level of evidence 4

Study Design: Narrative literature review. Objective: The numbers of low-energy cervical fractures seen in patients suffering from ankylosing spondylitis (also known as Bechterew disease) or diffuse idiopathic skeletal hyperostosis (also known as Forestier disease) have greatly increased over recent decades. These fractures tend to be particularly overlooked, leading to delayed diagnosis and secondary neurological deterioration. The aim of the present evaluation was to summarize current knowledge on cervical fractures in patients with ankylosing spinal disorders (ASDs). Methods: The literature was analyzed through an extensive PubMed search focusing on cervical fractures, especially with delayed diagnosis. Results: In ASDs, it was mainly the cervical spine that was found to be affected by fractures. Fifty percent of ASD patients had neurological deficits at admission, with a high probability of secondary deterioration due to an initially missed diagnosis. Multislice high-resolution imaging techniques should be the radiological standard of care if a vertebral fracture is suspected. Nevertheless, many of these spinal fractures are overlooked, leading to feared secondary deterioration of existing unstable fractures. Long posterior instrumentations were found to be the treatment of choice, followed by anterior and combined anterior-posterior instrumentations. Conclusions: Delayed diagnosis of cervical fractures in ASDs contributes to initially misinterpreted clinical symptoms, inadequate imaging techniques, and a lack of knowledge about this disease entity due to its peculiarities. Thorough assessment of the patients’ neurological morbidity at admission might reduce the occurrence of the associated fractures. The biomechanical behavior of ASD fractures is completely different from that of non-ASD fractures, so that the treatment strategy for these patients should be at least surgical, in combination with long dorsal instrumentations or combined anterior-posterior approaches.

Cervical corpectomies are increasingly used to treat degenerative, metastatic, inflammatory and traumatic multisegmental diseases. The postoperative results are thought to correlate mainly with the number of resected vertebral bodies. Thus, the aim of the study was to analyse complications and early outcome of these procedures to document the implant-related complications in order to set up a prospective clinical trial. Forty-five patients, who were treated in our department from 2011 to 2014 and who were available for a minimum follow-up of 1 year, were consecutively included in this retrospective evaluation. The median age was 61 (±11) years with a female to male sex ratio of 19 to 26, respectively. In these patients, cervical corpectomies (one-, two- and three-level procedures) were performed. The average number of resected levels was 1.2 levels. The intraoperative loss of blood (LOB), the red cell transfusions (rcT), the length of operation (LOO) and the usage of drains were investigated and correlated with intra- and postoperative complications. The mean LOO was 244 min (±68) with a mean LOB of 511 ml (±531). The overall complication rate was 22.9% (10 patients). Six patients (13.3%) had implant-related complications due to loosening and toggling of the screws and/or cage subsidence. Two patients (4.4%) had a postoperative haematoma and another two patients (4.4%) suffered from neurological deterioration due to an ongoing and severe myelopathic syndrome. All these patients received revision surgery. The average time from the first to revision surgery was 90 days. Cervical corpectomies still remain procedures with a high complication rate mainly represented by implant-related failures. These implant-related complications range from screw/plate loosening or toggling to graft dislocation with subsidence and might be associated with constructs extended to the C7 vertebral body. In our study population, the rate of implant failure was comparable to the literature, but not obviously correlated with the number of vertebral bodies resected. This may be attributed to the different disease entities. Thus, our results support the use of circumferential approaches for selected instability scenarios (metastatic or inflammatory diseases, kyphosis, osteoporosis, etc.) of one- and two-level corpectomies.

Introduction Primary malignant spinal astrocytomas present rare oncological entities with limited median survival and rapid neurological deterioration. Evidence on surgical therapy, adjuvant treatment, and neurological outcome is sparse. We aim to describe the treatment algorithm and clinical features on patients with infiltrating intramedullary astrocytomas graded WHO II–IV. Methods The following is a multicentered retrospective study of patients treated for spinal malignant glioma WHO II–IV in five high-volume neurosurgical departments from 2008 to 2019. Pilocytic astrocytomas were excluded. We assessed data on surgical technique, perioperative neurological status, adjuvant oncological therapy, and clinical outcome. Results 40 patients were included (diffuse astrocytoma WHO II n = 11, anaplastic astrocytoma WHO III n = 12, WHO IV n = 17). Only 40% were functionally independent before surgery, most patients presented with moderate disability (47.5%). Most patients underwent a biopsy (n = 18, 45%) or subtotal tumor resection (n = 15, 37.5%), and 49% of the patients deteriorated after surgery. Patients with WHO III and IV tumors were treated with combined radiochemotherapy. Median overall survival (OS) was 46.5 months in WHO II, 25.7 months in WHO III, and 7.4 months in WHO IV astrocytomas. Preoperative clinical status and WHO significantly influenced the OS, and the extent of resection did not. Conclusion Infiltrating intramedullary astrocytomas WHO II–IV present rare entities with dismal prognosis. Due to the high incidence of surgery-related neurological impairment, the aim of the surgical approach should be limited to obtaining the histological tissue via a biopsy or, tumor debulking in cases with rapidly progressive severe preoperative deficits.

This video demonstrates the step-by-step surgical technique for a less invasive cervical unilateral laminotomy for bilateral decompression (cervical ULBD). This technique allows surgeons to address bilateral cervical pathology while minimizing approach-related complications.1 In the video, we present the case of a 72-yr-old female patient with a past medical history of C3-C4 anterior cervical discectomy and fusion who presented in clinic with persistent posterior spinal cord compression and signal change. The patient had bilateral hand numbness, weakness, poor dexterity, and a positive Hoffman's sign. The patient was treated via a C3-C4 less invasive cervical ULBD using a mobile 3-dimensional (3D) C-arm (Ziehm Vision RFD 3D®, Nurnberg, Germany) combined with 3D computer navigation. Patient consent was obtained prior to performing the procedure. Contrary to anterior techniques, posterior cervical approaches avoid potential dysphasia, recurrent laryngeal nerve injury, and adjacent segment degeneration. Furthermore, the less invasive cervical ULBD results in decreased pain and postoperative narcotic usage, shorter hospital stays and fewer infections compared to open approaches, as well as a lower risk for postlaminectomy kyphosis and deformity, since it requires less muscle disruption and bony removal. Additionally, the use of total 3D navigation facilitates the workflow and minimizes radiation exposure.