Prevalence of Asymptomatic Deep Vein Thrombosis in Preoperative State of Spine Surgeries.

BACKGROUND: Deep venous thrombosis (DVT) is considered the most common cause of preventable death among hospitalized patients. A few studies have investigated the risk of venous thromboembolic events in patients undergoing elective spine surgery and reported varying incidences. We aim to assess the incidence of preoperative lower limb DVT in patients with lumbar degenerative disease undergoing elective surgery. METHODS: This is a retrospective review of prospectively collected data on adult patients with lumbar degenerative spine diseases (lumbar stenosis [LST], lumbar spondylolisthesis [SPL], or lumbar disc herniation) who were scheduled for operative management. Each patient underwent a preoperative lower limb venous Duplex (LLVD). Incidence of DVT, risk factors, and clinical course of patients were reported. RESULTS: Forty-nine patients (32 females; 65%) were included. All patients were diagnosed clinically and radiologically with lumbar degenerative diseases; LST (44.9%), SPL (36.7%), and lumbar disc herniation (18.4%), requiring surgical management. Three patients (6.1%) were found to have positive DVT studies, leading to the cancellation or rescheduling of their procedures (P < 0.01). These included 1 patient with LST (P = 0.045) and 2 patients with SPL (P = 0.006). Among patients with LST and SPL, higher disability (modified Rankin scale ≥3) was significantly associated with positive LLVD (P = 0.035). CONCLUSION: Patients with LST or SPL with higher preoperative disability scores were at higher risk to have preoperative DVT. Further research is needed to evaluate the feasibility and value of preoperative LLVD to detect DVT in patients planned for lumbar degenerative surgery.

Ultrasound Elastography in Neurosurgery: Current Applications and Future Perspectives.

BACKGROUND: Similar to clinical palpation, Ultrasound elastography (USE) helps distinguish between tissues by providing information on their elasticity. While it has been widely explored and has been applied to many body organs, USE has not been studied as extensively for application in neurosurgery. The current systematic review was performed to identify articles related to the use of interoperative USE in neurosurgery. METHODS: Search included MEDLINE(R) database. Only original peer-reviewed full-text articles were included. No language or publication year restrictions were imposed. Two independent reviewers assessed the search results for relevance. The identified articles were screened by title, abstract, and full-text review. RESULTS: Seventeen articles were included in the qualitative analysis and 13 articles were related to oncology, epilepsy (n = 3), and spine (n = 1). In oncology, USE was found useful in defining tumor stiffness, aiding surgical planning, detecting residual tumors, discriminating between tumor and brain tissue, and differentiating between different tumors. In epilepsy, USE could improve the detection of epileptogenic foci, thereby enhancing the prospect of complete and safe resection. The application in spinal surgery was limited to demonstrating that a compressed spinal cord is stiffer than the decompressed one. CONCLUSIONS: USE was found to be a safe, quick, portable, and economic tool that was a useful intraoperative adjunct to provide information corresponding to a variety of neurosurgical diseases, at different stages of surgery. This review describes the current intraoperative neurosurgical applications of USE, the concept of elasticity, and different USE modalities as well as the technical challenges, limitations, and possible future implications.

Effects of compressive lesions on intraoperative human spinal cord elasticity.

OBJECTIVE: Although evaluating tissue elasticity has various clinical applications, spinal cord elasticity (SCE) in humans has never been well documented. In this study, the authors aimed to evaluate the impact of compression on human SCE in vivo. METHODS: The authors prospectively assessed SCE using intraoperative shear wave elastography (SWE). All consecutive patients undergoing spinal cord (SC) decompression (laminectomy or corpectomy) between June 2018 and June 2019 were included. After intraoperative exposure of the patient's dura mater, at least three SWE measurements of the SC and its coverings were performed. Intraoperative neurological monitoring in the form of motor and somatosensory evoked potentials was utilized. Cases were divided into two groups based on the state of SC compression following bone removal (laminectomy or corpectomy): patients with adequate decompression (the decompressed SC group [DCG]) following bone removal and patients with remining compression, e.g., compressing tumor or instability (the compressed SC group [COG]). RESULTS: A total of 25 patients were included (8 females and 17 males) with a mean age of 48.28 ± 21.47 years. Most cases were degenerative diseases (10 cases) followed by tumors (6 cases), and the compression was observed at cervical (n = 14), thoracic (n = 9), and conus medullaris (n = 2) levels. The COG (6 cases) expressed significantly higher elasticity values, i.e., greater stiffness (median 93.84, IQR 75.27-121.75 kPa) than the decompressed SC in DCG (median 9.35, IQR 6.95-11.22 kPa, p < 0.001). Similarly, the compressed dura mater in the COG was significantly stiffer (mean ± SD 121.83 ± 70.63 kPa) than that in the DCG (29.78 ± 18.31 kPa, p = 0.042). Following SC decompression in COG, SCE values were significantly reduced (p = 0.006; adjusted for multiple comparisons). Intraoperative monitoring demonstrated no worsening from the baseline. CONCLUSIONS: The current study is to the authors' knowledge the first to quantitatively demonstrate increased stiffness (i.e., elasticity value) of the human SC and dura mater in response to external compression in vivo. It appears that SCE is a dynamic phenomenon and is reduced following decompression. Moreover, the evaluation of human SCE using the SWE technique is feasible and safe. Information from future studies aiming to further define SCE could be valuable in the early and accurate diagnosis of the compressed SC.

Shear wave elastography for intracranial epidermoid tumors.

BACKGROUND: Ultrasound elastography (USE) is a novel technique that assesses the mechanical properties of body tissues in real time. Based on elasticity measurements, USE enables the differentiation of tumor tissue from surrounding normal tissue. OBJECTIVES: We aimed to evaluate an intraoperative SWE technique for differentiating tumor tissue (epidermoid cyst) from the surrounding normal brain tissue based on elastic properties. METHODS: We prospectively report the intraoperative elasticity assessments of four patients diagnosed with epidermoid cysts. Along with standard ultrasonography, intraoperative shear wave elastography (SWE) was used to identify tumor tissue and assess the elasticity of each tumor and the surrounding normal brain. RESULTS: USE enabled the differentiation between epidermoid cysts and the surrounding normal brain tissue in real time intraoperatively; visual data (SWE elasticity map) and quantitative data (elasticity measurements in kilopascals) were utilized to identify the epidermoid cyst based on its elastic properties. The area representing the epidermoid cyst had an increased elasticity on SWE view and high mean elasticity values (193.7 ± 70.9 kPa in case 1, 168 ± 24.5 kPa in case 2, 205.1 ± 6.7 kPa in case 3, and 101.3 ± 12.6 kPa in case 4). The area representing the adjacent normal brain tissue on SWE view had lower mean elasticity values (14.9 ± 1.9 kPa in case 1, 22.6 ± 8.3 kPa in case 2, and 23.8 ± 1.4 kPa in case 4). CONCLUSION: This study demonstrates the feasibility and promising value of SWE as an intraoperative tool during epidermoid cyst resection. Epidermoid tissue remnants that are hidden from the microscopic view can be detected using SWE.

Needs of Young African Neurosurgeons and Residents: A Cross-Sectional Study.

Introduction: Africa has many untreated neurosurgical cases due to limited access to safe, affordable, and timely care. In this study, we surveyed young African neurosurgeons and trainees to identify challenges to training and practice. Methods: African trainees and residents were surveyed online by the Young Neurosurgeons Forum from April 25th to November 30th, 2018. The survey link was distributed via social media platforms and through professional society mailing lists. Univariate and bivariate data analyses were run and a P-value < 0.05 was considered to be statistically significant. Results: 112 respondents from 20 countries participated in this study. 98 (87.5%) were male, 63 (56.3%) were from sub-Saharan Africa, and 52 (46.4%) were residents. 39 (34.8%) had regular journal club sessions at their hospital, 100 (89.3%) did not have access to cadaver dissection labs, and 62 (55.4%) had never attended a WFNS-endorsed conference. 67.0% of respondents reported limited research opportunities and 58.9% reported limited education opportunities. Lack of mentorship (P = 0.023, Phi = 0.26), lack of access to journals (P = 0.002, Phi = 0.332), and limited access to conferences (P = 0.019, Phi = 0.369) were associated with the country income category. Conclusion: This survey identified barriers to education, research, and practice among African trainees and young neurosurgeons. The findings of this study should inform future initiatives aimed at reducing the barriers faced by this group.

Perception of Neurosurgery Residents and Attendings on Online Webinars During COVID-19 Pandemic and Implications on Future Education.

BACKGROUND: Online education has provided an important tool to continue medical education during the COVID-19 pandemic. Our study aimed to evaluate trainee and attending perceptions of online webinars as an educational tool in neurosurgery. METHODS: We conducted a cross-sectional survey study. A web-based 19-question survey was distributed to the people who attended the webinar series that was carried out by the Saudi Association of Neurological Surgery from March 29, 2020 to May 31, 2020. Candidates were identified through their registration e-mails. The survey was distributed June 5-8, 2020. RESULTS: A total of 156 responses were received (survey response rate: 60%). The overall satisfaction rate among residents and attendings (board-certified neurosurgeons) was similar (>80%). However, only 56.4% of attendings reported they were comfortable with online webinars compared with 81.2% of residents (P value <0.0001). Seventy-five percent of residents found online lectures more useful than traditional in-person lectures compared with 52% of attendings (P value = 0.01). CONCLUSIONS: Online educational webinars provide an educational value that can be considered as an adjunct to traditional (in-person) education methods. Among trainees, the satisfaction of neurosurgery webinars was encouraging to consider as an education method. More objective research and progress are required to adopt and refine existing online didactic and neurosurgical teaching tools while creating more engaging future distant learning models.

On the pedicle subtraction osteotomy technique and its modifications during the past two decades: a complementary classification to the Schwab's spinal osteotomy classification.

PURPOSE: To propose a complementary classification to the Schwab's osteotomy classification that would regroup together under a common umbrella different published pedicle subtraction osteotomy (PSO) variations that are commonly used, to have a common language and complete the spine surgeon's armamentarium when dealing with rigid spinal deformities. METHODS: The 2 general types corresponding to the grades 3 and 4 of the Schwab classification were separated into 6 gradual subtypes (grades 3A, 3B, 3C, 4A, 4B, 4C). The classification is based on the amount of resected pedicle, the inclusion or not of the disc above, and the location of the axis of rotation. Based on the proposed classification, a reliability study was performed using 18 cases that were classified by 8 readers with expertise in the management of adult deformities with the use of osteotomies. RESULTS: Clinical cases were classified according to the 6 grades proposed in the classification. The intra-rater reliability for the classification was "almost perfect agreement" with a Fleiss kappa coefficient average of 0.92 (range 0.85-1.00). The inter-rater reliability was "almost perfect agreement" with a coefficient average of 0.90 for the 2 readings that were done at an interval of 2 weeks. CONCLUSION: The developed classification proved to be reliable and intuitive. It is an original way to display a catalog of different available PSO modifications including the original technique, in a logical and gradual order to help the surgeons in their decisions and show them that between a grade 2 osteotomy and a grade 5 osteotomy, many intermediate options are available. Further work with a treatment algorithm for clinical practice based on the current classification may be developed in the future.

Association between craniovertebral junction abnormalities and syringomyelia in patients with chiari malformation type-1.

OBJECTIVE: To assess the correlation between craniovertebral junction (CVJ) abnormalities and syringomyelia in patients with Chiari malformation type-1 (CM1). METHODS: This was a retrospective study including patients with CM1. Identification of cases was done by searching a radiology database at a university hospital from 2012 to 2017. Patients were divided into 2 groups based on whether CVJ abnormalities were present (CVJ+) or absent (CVJ-). The patients` demographic and clinical data were reviewed. All magnetic resonance imaging studies were examined by a certified neuroradiologist. RESULTS: Sixty-four consecutive patients with CM1 were included. The mean age was 24+/-17 years; 59% were females. The CVJ+ group had more female patients (p=0.012). The most frequent CVJ abnormality was platybasia (71%), followed by short clivus (44%) and cervical kyphosis (33%). The CVJ abnormalities were more in Syringomyelia cases (p=0.045). However, the results were not significant when hydrocephalus cases were excluded. CONCLUSION: Among CM1 patients, CVJ abnormalities were found more in patients with syringomyelia. Future studies with larger sample size are required to further study the correlation between CVJ abnormalities and both syringomyelia and hydrocephalus in CM1 patients.

The longitudinal impact of COVID-19 pandemic on neurosurgical practice.

OBJECTIVE: This observational cross-sectional multicenter study aimed to evaluate the longitudinal impact of the coronavirus disease 2019 (COVID-19) pandemic on neurosurgical practice. METHODS: We included 29 participating neurosurgeons in centers from all geographical regions in the Kingdom of Saudi Arabia. The study period, which was between March 5, 2020 and May 20, 2020, was divided into three equal periods to determine the longitudinal effect of COVID-19 measures on neurosurgical practice over time. RESULTS: During the 11-week study period, 474 neurosurgical interventions were performed. The median number of neurosurgical procedures per day was 5.5 (interquartile range [IQR]: 3.5-8). The number of cases declined from 72 in the first week and plateaued at the 30's range in subsequent weeks. The most and least number of performed procedures were oncology (129 [27.2 %]) and functional procedures (6 [1.3 %]), respectively. Emergency (Priority 1) cases were more frequent than non-urgent (Priority 4) cases (178 [37.6 %] vs. 74 [15.6 %], respectively). In our series, there were three positive COVID-19 cases. There was a significant among-period difference in the length of hospital stay, which dropped from a median stay of 7 days (IQR: 4-18) to 6 (IQR: 3-13) to 5 days (IQR: 2-8). There was no significant among-period difference with respect to institution type, complications, or mortality. CONCLUSION: Our study demonstrated that the COVID-19 pandemic decreased the number of procedures performed in neurosurgery practice. The load of emergency neurosurgery procedures did not change throughout the three periods, which reflects the need to designate ample resources to cover emergencies. Notably, with strict screening for COVID -19 infections, neurosurgical procedures could be safely performed during the early pandemic phase. We recommend to restart performing neurosurgical procedures once the pandemic gets stabilized to avoid possible post pandemic health-care system intolerable overload.

Atypical Imaging of Hemorrhagic Lumbosacral Myxopapillary Ependymoma with Histopathological Correlation: A Case Report.

BACKGROUND Spinal myxopapillary ependymoma (MPE) is a slow-growing tumor arising from ependymal cells of the central nervous system. MPE rarely presents with acute neurological compromise and most commonly occur in the filum terminale or conus medullaris region. To date, only a few cases have been reported of patients presenting acutely because of hemorrhagic MPE. CASE REPORT A 16-year-old boy without previous medical problems presented with a sudden onset of severe pain in the low back radiating to the thighs. He could not walk owing to the severity of the pain. Neurological examination revealed an unsteady gait, but the rest of the motor and sensory examination was normal. Lumbosacral spine magnetic resonance imaging revealed an intradural hemorrhagic mass extending from L5 to S2. The encapsulated hemorrhagic tumor was resected, and the pathology was consistent with MPE grade I. The patient made a significant recovery postoperatively. It is extremely rare for MPE to present with spontaneous hemorrhage in the lumbosacral region. Prompt diagnosis and management led to a favorable outcome. This case report is intended to highlight the atypical presentation and imaging features of hemorrhagic MPE. CONCLUSIONS We described a rare case of MPE in the lumbosacral region of a patient who presented with acute neurological compromise and atypical imaging features.

The World Federation of Neurosurgical Societies Young Neurosurgeons Survey (Part I): Demographics, Resources, and Education.

BACKGROUND: Providing a comprehensive and effective neurosurgical service requires adequate numbers of well-trained, resourced, and motivated neurosurgeons. The survey aims to better understand 1) the demographics of young neurosurgeons worldwide; 2) the challenges in training and resources that they face; 3) perceived barriers; and 4) needs for development. METHODS: This was a cross-sectional study in which a widely disseminated online survey (April 2018-November 2019) was used to procure a nonprobabilistic sample from current neurosurgical trainees and those within 10 years of training. Data were grouped by World Bank income classifications and analyzed using χ2 tests because of its categorical nature. RESULTS: There were 1294 respondents, with 953 completed responses included in the analysis. Of respondents, 45.2% were from high-income countries (HICs), 23.2% from upper-middle-income countries, 26.8% lower-middle-income countries, and 4.1% from low-income countries. Most respondents (79.8%) were male, a figure more pronounced in lower-income groups. Neuro-oncology was the most popular in HICs and spinal surgery in all other groups. Although access to computed tomography scanning was near universal (98.64%), magnetic resonance imaging access decreased to 66.67% in low-income countries, compared with 98.61% in HICs. Similar patterns were noted with access to operating microscopes, image guidance systems, and high-speed drills. Of respondents, 71.4% had dedicated time for neurosurgical education. CONCLUSIONS: These data confirm and quantify disparities in the equipment and training opportunities among young neurosurgeons practicing in different income groups. We hope that this study will act as a guide to further understand these differences and target resources to remedy them.

The World Federation of Neurosurgical Societies Young Neurosurgeons Survey (Part II): Barriers to Professional Development and Service Delivery in Neurosurgery.

BACKGROUND: Strengthening health systems requires attention to workforce, training needs, and barriers to service delivery. The World Federation of Neurosurgical Societies Young Neurosurgeons Committee survey sought to identify challenges for residents, fellows, and consultants within 10 years of training. METHODS: An online survey was distributed to various neurosurgical societies, personal contacts, and social media platforms (April-November 2018). Responses were grouped by World Bank income classification into high-income countries (HICs), upper middle-income countries (UMICs), low-middle-income countries (LMICs), and low-income countries (LICs). Descriptive statistical analysis was performed. RESULTS: In total, 953 individuals completed the survey. For service delivery, the limited number of trained neurosurgeons was seen as a barrier for 12.5%, 29.8%, 69.2%, and 23.9% of respondents from HICs, UMICs, LMICs, and LICs, respectively (P < 0.0001). The most reported personal challenge was the lack of opportunities for research (HICs, 34.6%; UMICs, 57.5%; LMICs, 61.6%; and LICs, 61.5%; P = 0.03). Other differences by income class included limited access to advice from experienced/senior colleagues (P < 0.001), neurosurgical journals (P < 0.0001), and textbooks (P = 0.02). Assessing how the World Federation of Neurosurgical Societies could best help young neurosurgeons, the most frequent requests (n = 953; 1673 requests) were research (n = 384), education (n = 296), and subspecialty/fellowship training (n = 232). Skills courses and access to cadaver dissection laboratories were also heavily requested. CONCLUSIONS: Young neurosurgeons perceived that additional neurosurgeons are needed globally, especially in LICs and LMICs, and primarily requested additional resources for research and subspecialty training.

Neurosurgical Procedures and Safety During the COVID-19 Pandemic: A Case-Control Multicenter Study.

OBJECTIVE: Quantitative documentation of the effects of outbreaks, including the coronavirus disease 2019 (COVID-19) pandemic, is limited in neurosurgery. Our study aimed to evaluate the effects of the COVID-19 pandemic on neurosurgical practice and to determine whether surgical procedures are associated with increased morbidity and mortality. METHODS: A multicenter case-control study was conducted, involving patients who underwent neurosurgical intervention in the Kingdom of Saudi Arabia during 2 periods: pre-COVID-19 and during the COVID-19 pandemic. The surgical intervention data evaluated included diagnostic category, case priority, complications, length of hospital stay, and 30-day mortality. RESULTS: A total of 850 procedures were included, 36% during COVID-19. The median number of procedures per day was significantly lower during the COVID-19 period (5.5 cases) than during the pre-COVID-19 period (12 cases; P < 0.0001). Complications, length of hospital stay, and 30-day mortality did not differ during the pandemic. In a multivariate analysis comparing both periods, case priority levels 1 (immediate) (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.24-2.67), 1 (1-24 h) (OR, 1.63; 95% CI, 1.10-2.41), and 4 (OR, 0.28; 95% CI, 0.19-0.42) showed significant differences. CONCLUSIONS: During the early phase of the COVID-19 pandemic, the overall number of neurosurgical procedures declined, but the load of emergency procedures remained the same, thus highlighting the need to allocate sufficient resources for emergencies. More importantly, performing neurosurgical procedures during the pandemic in regions with limited effects of the outbreak on the health care system was safe. Our findings may aid in developing guidelines for acute and long-term care during pandemics in surgical subspecialties.

In vivo assessment of spinal cord elasticity using shear wave ultrasound in dogs.

OBJECTIVE: Evaluation of living tissue elasticity has wide applications in disease characterization and prognosis prediction. Few previous ex vivo attempts have been made to characterize spinal cord elasticity (SCE). Recently, tissue elasticity assessment has been clinically feasible using ultrasound shear wave elastography (SWE). The current study aims to characterize SCE in healthy dogs, in vivo, utilizing SWE, and to address SCE changes during compression. METHODS: Ten Greyhound dogs (mean age 14 months; mean weight 14.3 kg) were anesthetized and tracheally intubated, with hemodynamic and neurological monitoring. A 3-level, midcervical laminectomy was performed. SCE was assessed at baseline. Next, 8- and 13-mm balloon compressions were sequentially applied ventral to the spinal cord. RESULTS: The mean SCE was 18.5 ± 7 kPa. Elasticity of the central canal, pia mater, and dura mater were 21.7 ± 9.6 kPa, 26.1 ± 14.8 kPa, and 63.2 ± 11.5 kPa, respectively. As expected, the spinal cord demonstrated less elasticity than the dura mater (p < 0.0001) and pia mater (trend toward significance p = 0.08). Notably, the 13-mm balloon compression resulted in a stiffer spinal cord than at baseline (233 ± 73 kPa versus 18.5 ± 7 kPa, p < 0.0001) and 8-mm balloon compression (233 ± 73 kPa versus 185 ± 68 kPa, p < 0.048). CONCLUSIONS: In vivo SCE evaluation using SWE is feasible and comparable to earlier reports, as demonstrated by physical sectioning of the spinal cord. The compressed spinal cord is stiffer than a free spinal cord, with a linear increase in SCE with increasing mechanical compression. Knowledge of the biomechanical properties of the spinal cord including SCE has potential implications for disease management and prognosis.

Quantitative assessment of vertebral artery anatomy in relation to cervical pedicles: surgical considerations based on regional differences.

OBJECTIVE: To quantify the anatomic relationship between the Cervical pedicle screw (CPS), vertebral artery (VA), and related anatomic structures in the Saudi population. METHODS: This retrospective single center study included 50 consecutive patients (35 males) with normal neck findings on computed tomography angiography performed for trauma or vascular evaluation between 2012 and 2014. Radiologic parameters were assessed and correlated with age, weight, height, and body mass index (BMI). RESULTS: Mean age, weight, height, and BMI were 45.74+/-18.93 years, 79.72+/-21.80 kg, 164.74+/-11.53 cm, and 29.38+/-6.13 kg/m2, respectively. Mean cervical pedicle diameter (PD) increased from the cranial to caudal vertebrae (p=0.0001). Mean free zone (FZ) value, defined as the distance between the lateral CP border and medial VA border, was 1 mm (range 0.95-1.16 mm). The VA entry into the transverse foramina was at C6 level on both the right 92% and left side in most patients 94%. However, the right and left side level of VA entry differed in 14% of individuals. CONCLUSION: The PD and FZ are smaller in Saudi Arabians than in western populations. Assessment of VA entry at each level should be performed on an individual basis as the level of VA entry can differ in the same patient. Anatomic variations between different geographic areas should be studied to provide better surgical guidance.

The Top-100 Most-Cited Articles on Meningioma.

BACKGROUND: There is an abundance of articles published on meningioma. OBJECTIVE: To identify the 100 most-cited articles on meningioma and to perform a bibliometric analysis. METHODS: In November 2016, we performed a title-specific search of the Scopus database using "meningioma" as our search query term without publication date restrictions. The top 100 most cited articles were obtained and reviewed. RESULTS: The top 100 most cited articles received a mean 198 citations per paper. Publication dates ranged from 1953 to 2013; most articles were published between 1994 and 2003, with 50 articles published during that period. NEUROSURGERY published the greatest number of top cited articles (22 of 100). The most frequent study categories were laboratorial studies (31 of 100) and natural history studies (28 of 100). Nonoperative management studies were twice as common as operative management studies in the top-cited articles. Neurosurgery as a specialty contributed to 50% of the top 100 list. The most contributing institute was the Mayo Clinic (11%); the majority of the top cited articles originated in the United States (53%). CONCLUSIONS: We identified the top 100 most-cited articles on meningioma that may be considered significant and impactful works, as well as the most noteworthy. In addition, we recognized the historical development and advances in meningioma research and the important contributions of various authors, specialty fields, and countries. A large proportion of the most cited articles were written by authors other than neurosurgeons, and many of these articles were published in non-neurosurgery journals.