Resection Of Spinal Cord Tumors Research Articles

Intraoperative Neurophysiologic Monitoring and Mapping During Surgery on Intramedullary Spinal Cord Tumors in Children and Adolescents.

Surgical resection of intramedullary spinal cord tumors carries significant risks of neurologic deficits, especially in cases of infiltrative tumors. In pediatric patients, this type of surgery may be associated with a high risk of poor neurologic outcome. Intraoperative neurophysiologic monitoring has been adopted as part of the clinical routine by many centers as a useful adjunct for intraoperative assessment of neurologic integrity. To what extent intraoperative neurophysiologic mapping strategies may further support intraoperative decision-making is still a matter of debate. Here, we report on a small cohort of five pediatric patients in whom mapping with the double-train paradigm was used to identify the dorsal column and corticospinal tract and to guide the surgical resection. We also discuss the possible benefits and challenges regarding the available literature.

What Factors Predict the Development of Neurologic Deficits Following Resection of Intramedullary Spinal Cord Tumors: A Multi-Center Study

Intramedullary spinal cord tumors are challenging to resect, and their postoperative neurological outcomes are often difficult to predict, with few studies assessing this outcome. We reviewed the medical records of all patients surgically treated for Intramedullary spinal cord tumors at our multisite tertiary care institution (Mayo Clinic Arizona, Mayo Clinic Florida, Mayo Clinic Rochester) between June 2002 and May 2020. Variables that were significant in the univariate analyses were included in a multivariate logistic regression. "MissForest" operating on the Random Forest algorithm, was used for data imputation, and K-prototype was used for data clustering. Heatmaps were added to show correlations between postoperative neurological deficit and all other included variables. Shapley Additive exPlanations were implemented to understand each feature's importance. Our query resulted in 315 patients, with 160 meeting the inclusion criteria. There were 53 patients with astrocytoma, 66 with ependymoma, and 41 with hemangioblastoma. The mean age (standard deviation) was 42.3 (17.5), and 48.1% of patients were women (n= 77/160). Multivariate analysis revealed that pathologic grade >3 (OR=1.55; CI=[0.67, 3.58], P= 0.046 predicted a new neurological deficit. Random Forest algorithm (supervised machine learning) found age, use of neuromonitoring, histology of the tumor, performing a midline myelotomy, and tumor location to be the most important predictors of new postoperative neurological deficits. Tumor grade/histology, age, use of neuromonitoring, and myelotomy type appeared to be most predictive of postoperative neurological deficits. These results can be used to better inform patients of perioperative risk.

Effect of race, sex, and socioeconomic factors on overall survival following the resection of intramedullary spinal cord tumors.

Intramedullary spinal cord tumors (IMSCTs) account for 2-4% of all primary CNS tumors. Given their low prevalence and the intricacy of their diagnosis and management, it is critical to address the surrounding racial and socioeconomic factors that impact the care of patients with IMSCTs. This study aimed to investigate the association between race and socioeconomic factors with overall 5year mortality following the resection of IMSCTs. The study used the National Cancer Database to retrospectively analyze patients who underwent resection of IMSCTs from 2004 to 2017. Patients were divided into four cohorts by race/ethnicity, facility type, insurance, median income quartiles, and living area. The primary outcome of interest was 5year survival, and secondary outcomes included postoperative length of stay and 30day readmission. Descriptive and multivariable analyses were used to identify independent factors associated with mortality, with statistical significance assessed at a 2-sided p < 0.05. We evaluated the patient characteristics and outcomes for 8,028 patients who underwent surgical treatment for IMSCTs between 2004 and 2017. Most patients were white males (52.4%) with a mean age of 44 years where 7.17% of patients were Black, 7.6% were Hispanic, and 3% were Asian. Most were treated in an academic/research program (72.4%) and had private insurance (69.2%). Black patients had a higher odd of 5year mortality (OR 1.4; 95% CI 1.1 to 1.77; p = 0.04) compared to white patients, while no significant differences in mortality were observed among other races. Factors associated with lower odds of mortality included being female (OR 0.89; 95% CI 0.78 to 1.02; p < 0.01), receiving treatment in an academic/research program (OR 0.51; 95% CI 0.33 to 0.79; p = 0.04), having private insurance (OR 0.65; 95% CI 0.45 to 0.93; p = 0.02), and having higher income quartiles (OR 0.77; 95% CI 0.62 to 0.96; p = 0.02). Our study sheds light on the healthcare disparities that exist in the surgical management of IMSCTs. Our findings indicate that race, sex, socioeconomic status, and treatment facility are independent predictors of 5year mortality, with Black patients, males, those with lower socioeconomic status, and those treated at non-academic centers experiencing significantly higher mortality rates. These alarming disparities underscore the urgent need for policymakers and researchers to address the underlying factors contributing to these discrepancies and provide equal access to high-quality surgical care for patients with IMSCTs.

Dorsal column mapping in resection of intramedullary spinal cord tumors: a prospective comparison of two methods and neurological follow-up

PurposeIn surgery for intramedullary spinal cord tumors (imSCT), distortion of the anatomy challenges the visual identification of dorsal columns (DC) for midline myelotomy. Dorsal column mapping (DCM) and spinal cord stimulation (SCS) can identify DC neurophysiologically. We compare application and feasibility of both methods.MethodsPatients with surgically treated imSCT were prospectively included between 04/2017 and 06/2019. The anatomical midline (AM) was marked. SSEPs at the DC after stimulation of tibial/median nerve with an 8-channel DCM electrode and cortical SSEP phase reversal at C3/C4 after SCS using a bipolar concentric probe were recorded. Procedural and technical aspects were compared. Standardized neurological examinations were performed preoperatively, 1 week postoperatively and after more than 12 months.ResultsThe DCM electrode detected the midline in 9/13 patients with handling limitations in the remaining patients. SCS was applicable in all patients with determination of the midline in 9/13. If both recordings could be acquired (6/13), concordance was 100%. If baseline SSEPs were poor, both methods were limited. SCS was less time-consuming (p = 0.001), cheaper, and easier to handle. In 92% of cases, the AM and neurophysiologic midlines were concordant. After myelotomy, 3 patients experienced > 50% reduction in amplitude of SSEPs. Despite early postoperative worsening of DC function, long-term follow-up showed significant recovery and improvement in quality of life.ConclusionDCM and SCS may help confirm and correct the AM for myelotomy in imSCT, leading to a favorable long-term neurological outcome in this cohort. SCS evolved to be superior concerning applicability, cost-effectiveness, and time expenditure.

Assessment of intraoperative neurophysiological monitoring techniques in intramedullary spinal cord tumor removal surgery

ObjectiveIntraoperative neurophysiological monitoring in intramedullary spinal cord tumor removal surgery helps surgeons detect early warning signs of postoperative nerve damage, in order to reduce or prevent permanent neuron injury. We performed a study to evaluate the value of intraoperative neurophysiological monitoring techniques in intramedullary spinal cord tumor resection surgery. MethodsWe performed a retrospective study of 29 patients undergoing surgery for intramedullary spinal cord tumors and intraoperative neurophysiological monitoring from 2017 to 2021 at the University Medical Center, Ho Chi Minh City. Clinical assessment before and after surgery, intraoperative neurophysiological monitoring to find out the sensitivity, specificity, positive predictive value, and negative predictive value of intraoperative neurophysiological monitoring techniques were performed. ResultsOf the 29 patients, 4 patients had worse postoperative neurological symptoms (13.8%) at 1 day after surgery. The rate of postoperative worsening neurological symptoms decreased to 10.3% at the 1-month follow-up. SSEP (somatosensory evoked potential) had 75% sensitivity and 72% specificity in detecting postoperative nerve damage, while the sensitivity and specificity of MEP (motor evoked potential) were 100% and 80%, respectively. ConclusionBoth SSEP and MEP have a high sensitivity in detecting postoperative nerve damage, meanwhile, MEP is more sensitive than SSEP. These techniques help predict and possibly prevent timely neurological damage during intramedullary spinal cord resection surgery.

Early Phase Functional Recovery after Spinal Intramedullary Tumor Resection Could Predict Ambulatory Capacity at 1 Year after Surgery.

This is a single-center retrospective cohort study with a university hospital setting. This study aims to evaluate the short-term course of physical function and walking ability after intramedullary spinal cord tumor (ISCT) resection and predict walking independence 1 year after surgery. Although several reports have shown the postoperative functional prognosis of spinal intramedullary tumors with long-term follow-up, no reports have identified the predictors associated with the functional outcome at an early stage. A total of 79 individuals who underwent ISCT resection at our institute between 2014 and 2019 were enrolled in the study, whose preoperative walking state was independent ambulator regardless of cane support with the Functional Independence Measure Locomotor Scale (FIM-L) score of ≥6. The FIM-L, the American Spinal Injury Association (ASIA) motor and sensory scores in the lower extremities, and the Walking Index for Spinal Cord Injury II (WISCI II) were assessed for walking independence, lower-limb function, and walking ability, respectively. These evaluations were performed at 4 time points: preoperatively, 1 week (1W), 2 weeks (2W), and 1 year after surgery. In the early phase after surgery, 71% and 43% of the participants were nonindependent ambulators at 1W and 2W, respectively. Histopathology indicated that patients with solid tumors (ependymoma, astrocytoma, or lipoma) showed significantly lower indices at 1W and 2W than those with vascular tumors (hemangioblastoma or cavernous hemangioma). Regarding tumor location, thoracic cases exhibited poorer lower-limb function at 1W and 2W and poorer walking ability at 2W than cervical cases. According to the receiver operating characteristic (ROC) analysis, 2 WISCI II points at 2W had the highest sensitivity (100%) and specificity (92.2%) in predicting the level of walking independence at 1 year postoperatively (the area under the ROC curve was 0.99 (95% confidence interval, 0.93-1.00). The higher the lower-limb function scores in the early phase, the better the improvement in walking ability is predicted 1 year after ISCT resection.

Complication Avoidance in Neurosurgery with Use of Intraoperative Ultrasonography.

Intraoperative ultrasonography is an extremely valuable tool for avoidance of complications during neurosurgical procedures, including resection of intracranial and spinal cord tumors, removal of spontaneous intracerebral hemorrhages and arteriovenous malformations, and ventricular access for shunt placements. Nevertheless, application of this highly useful technique may be accompanied by some challenges and difficulties, as well as human errors; thus, it requires specific knowledge and continuous training.

Perioperative lumbar subarachnoid drainage could not prevent postoperative CSF leakage after spinal cord tumor resection using an artificial dura mater

BackgroundCerebrospinal fluid (CSF) leakage occurs in patients who undergo dural repair using artificial dura mater. This study aimed to determine if perioperative lumbar subarachnoid drainage could reduce the incidence of postoperative CSF leakage in cases of dural repair using artificial dura mater. MethodsWe retrospectively analyzed 84 patients (41 men, 43 women; mean age, 52.2 ± 20.1 years) who underwent intradural spinal cord tumor resection and dural repair using artificial dura mater. These patients were divided according to whether they underwent perioperative lumbar subarachnoid drainage (39 patients: D group) or had no drainage (45 patients: ND group). The incidence of radiographic and symptomatic CSF leakage as well as baseline characteristics and operative data were compared between the two groups. ResultsRadiographic CSF leakage was observed in 21 patients (25.0%), including 10 (25.6%) in the D group and 11 (24.4%) in the ND group. Symptomatic CSF leakage was observed in 12 patients (14.2%), including six (15,4%) in the D group and 11 (13.3%) in the ND group. There were no significant differences in the incidence of subcutaneous CSF accumulation and symptomatic CSF leakage between the two groups. In cases with symptomatic CSF leakage, the onset time of CSF leakage tended to be earlier (5.7 days vs 15.7 days), and the treatment period tended to be longer (5.8 weeks vs 2.8 weeks) in the ND group than in the D group. ConclusionsPerioperative lumbar subarachnoid drainage did not reduce the incidence of either radiographic or symptomatic CSF leakage. However, it might shorten the treatment period and reduce refractory CSF leakage, which requires multiple treatments over a long period.

Relevance of intraoperative motor evoked potentials and D-wave monitoring for the resection of intramedullary spinal cord tumors in children.

The purpose of this study was to evaluate the reliability of motor evoked potentials (MEP), somatosensory evoked potentials (SSEP), and D-wave monitoring as predictors of postoperative neurological deficits in pediatric patients undergoing resection of intramedullary spinal cord tumors (IMSCTs). Additionally, we aimed to determine whether alerts in the intraoperative neurophysiological monitoring (IONM) influenced the extent of resection (EOR). A retrospective analysis of the pediatric patients who underwent resection of IMSCT between March 2010 and April 2021 with an IONM guidance was performed. IONM alerts were recorded and correlated with patients' clinical status at discharge. Twenty three pediatric patients were included. MEP and SSEP were successfully elicited in all patients, while D-wave monitoring was feasible for 14 of them (60.9%). Significant IONM alerts occurred in 6 individuals (26.1%) with monitorable MEP and SSEP and 2 patients with monitorable D-waves (14.3%). The sensitivity, specificity, positive predictive value, and negative predictive value accounted for 100%, 81.8%, 20%, 100% for MEP, 100%, 92.3%, 50%, 100% for D-wave, and 50%, 81%, 20%, 94.44% for SSEP, respectively. Both MEP (p < 0.001) and D-wave monitoring (p < 0.001) accurately predicted postoperative motor deficits, while SSEP failed to provide significant accuracy regarding sensory deficits (p = 0.491). Gross-total tumor resection was performed in 29.4% of patients without IONM alerts and 33.3% of patients with IONM alerts, indicating that IONM alerts did not limit the EOR (p = 0.0857). MEP and D-wave monitoring can be perceived as reliable IONM modalities in pediatric IMSCTs surgery. Caution is needed with the implementation of SSEP to guide surgical decisions.

Resection of disseminated recurrent myxopapillary ependymoma with more than 4-year follow-up: operative nuance for prolonged prone position. Illustrative case.

BACKGROUNDSymptomatic disseminated myxopapillary ependymoma (MPE) in a young person presents a daunting challenge because the risks of prolonged prone positioning and spinal cord injury may outweigh the likelihood of attaining the benefit of gross total resection.OBSERVATIONSThe authors reported the case of a 15-year-old girl with five discrete recurrent spinal cord ependymomas. The patient received a 25-hour surgical procedure for gross total resection of the tumors and fusion over an approximately 33-hour period. She experienced complete resolution of all preoperative neurological symptoms and subsequently received adjuvant radiation therapy. At 52 months after surgery, she was still experiencing neurologically intact, progression-free survival. This case illustrated one of the most extensive recurrent tumor resections for MPE with prolonged disease-free survival reported to date. It may also represent the longest prone position spinal case reported and was notable for a lack of any of the complications commonly associated with the prolonged prone position.LESSONSThe authors discussed the complexity of surgical decision-making in a symptomatic patient with multiple disseminated metastases, technical considerations for resection of intradural and intramedullary spinal cord tumors, and considerations for avoiding complications during prolonged positioning necessary for spinal surgery.

Subdural Direct Wave Intraoperative Neurophysiological Monitoring in Intramedullary Spinal Cord Tumor Resection: Case Report

ABSTRACT Direct wave (D-wave) intraoperative neurophysiological monitoring (IONM) is used during intramedullary spinal cord tumor (IMSCT) resection to assess corticospinal tract (CST) integrity. There are several obstacles to obtaining consistent and reliable D-wave monitoring and modifications to standard IONM procedures may improve surgical resection. We present the case of a subependymoma IMSCT resection at the T2–T6 spinal levels where subdural D-wave monitoring was implemented. A 47-year-old male was presented with a five-year history of numbness in his right foot eventually worsening to sharp upper back pain with increased lower extremity spasticity. MRI revealed an expansile non-contrast enhancing multi-loculated cystic lesion spanning T2–T6 as well as a separate T1–T2 lesion. A T2–T6 laminoplasty was performed for intramedullary resection of the lesion. A spinal electrode was placed in the epidural space caudal to the surgical site to monitor CST function; however, action potentials could not be obtained. Post durotomy, the electrode was placed in the subdural space under direct visualization. This resulted in a reliable D-wave recording, which assisted surgical decision-making during the procedure upon D-wave and limb motor evoked potential attenuation. Surgical intervention led to the recovery of the D-wave recording. Subdural D-wave monitoring serves as an alternative in patients where reliable D-waves from the epidural space are unable to be obtained. Further investigation is required to improve the recording technique, including exploring various types of contacts and lead placement locations.

Incidence and Predictors of Postoperative Kyphotic Deformity after Thoracic Spinal Cord Tumor Resection.

Introduction Kyphotic deformity is common after spinal tumor resection surgery. An adequate field of view is needed to resect the spinal cord tumor, and, in some cases, the facet joint must be removed during laminectomy, and fixation may be performed simultaneously. In this study, we investigated the incidence of postoperative deformity after spinal tumor resection and the factors associated with postoperative deformity. Methods We retrospectively analyzed patients who underwent thoracic spinal cord tumor resection at a single institution between 2010 and 2017 and were followed up for at least 24 months after surgery. Fifty percent or more of the facet joint was removed during the laminectomy, and fixation was performed simultaneously. Patients were divided into two groups, with and without kyphotic deformity. Patient demographic characteristics (age at surgery and gender), whether they underwent primary surgery or reoperation, tumor level, pathological type, and surgical method were compared. Multiple linear regression analysis was performed to identify independent predictors of kyphotic deformity. Results Thirty-one patients were found to be eligible. Thirteen patients had intramedullary spinal cord tumors. Laminectomy was performed in 52% (N=16), laminoplasty in 6% (N=2), and laminectomy and/or laminoplasty combined with fusion in 42% (N=13) of the patients. During a mean follow-up period of 66.8 months, 12 (39%) patients had postoperative kyphosis deformities, of which one patient (3%, a 12-year-old girl who underwent combined postoperative radiation therapy) underwent kyphosis correction surgery three years after surgery. The number of laminectomies was independently associated with kyphotic deformity. Conclusions Although kyphotic deformity after spinal tumor surgery was observed in about 39% of the patients, corrective surgery was rarely required due to the progression of the deformity. The high number of laminectomies is a risk factor for postoperative kyphosis, and prophylactic fixation may be considered in cases of multiple laminectomies.

WS5.4. EMG Monitoring: Free-Run and Triggered

The recording of compound muscle action potentials (CMAPs) in response to spontaneous or electrically stimulation of the cranial, spinal, peripheral nerves or nerve root activation is known as intraoperative electromyography (EMG). EMG monitoring is widely used in surgeries when the aforementioned neural structures might be at risk. It allows early detection of surgery- related nerve injury so that proper intervention can be accordingly adopted; it also allows confirmation of the functional status of the nerve. The intraoperative monitoring team must thoroughly understand the nervous pathways that require monitoring and mapping in order to develop optimal stimulation and recording strategies for each surgical procedure. Intraoperative EMG testing includes triggered EMG (tEMG) for mapping and free-run EMG (fEMG) for monitoring purposes. Triggered EMG is used to identify the nerves and nerve root, to define a safe entry pathway to access the lesion, or to assess the functional integrity of the nerve so that the surgical plan can be modified accordingly. Clinical applications of tEMG also include confirmation of the placement of pedicle screws during spine surgery and guiding the sectioning of the lumbosacral rootlets during selective dorsal rhizotomy. The following three kinds of stimulation electrodes are available: monopolar, bipolor, and tripolar electrode. Each of the aforementioned electrodes are associated with certain strengths and weakness; thus, they can be used under different circumstances and meets most of our clinical needs. fEMG involves recording spontaneous or evoked muscle activity without interfering with the surgery. It is used as a monitoring tool to detect surgically driven mechanical irritation of the peripheral nerves and motor cranial nerves, hopefully before permanent damage occurs. It also can be applied to detect muscle activity evoked by mechanical irritation of the corticospinal tract and/or alpha motor neurons during brain tumor or intramedullary spinal cord tumor resection. There are three types of fEMG activity, referred to as the A, B and C train. Among them, the A train has been more associated with poor postoperative outcomes, although false-positive and false-negative findings do exist. Thus, the concomitant use of somatosensory and motor evoked potentials will certainly increase the sensitivity and specificity of fEMG.

Delayed variations in the diagnostic accuracy of intraoperative neuromonitoring in the resection of intramedullary spinal cord tumors.

The use of intraoperative neuromonitoring (IONM) has become an imperative adjunct to the resection of intramedullary spinal cord tumors (IMSCTs). While the diagnostic utility of IONM during the immediate postoperative period has been previously studied, its long-term diagnostic accuracy has seldom been thoroughly assessed. The aim of this study was to evaluate long-term variations in the diagnostic accuracy of transcranial motor evoked potentials (tcMEPs), somatosensory evoked potentials (SSEPs), and D-wave recordings during IMSCT excision. The authors performed a retrospective evaluation of imaging studies, patient charts, operative reports, and IONM recordings of patients who were operated on for gross-total or subtotal resection of IMSCTs at a single institution between 2012 and 2018. Variations in the specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) for postoperative functional outcome (McCormick Scale) were analyzed at postoperative day 1 (POD1), 6 weeks postoperatively (PO-6 weeks), and at the latest follow-up. Overall, 28 patients were included. The mean length of follow-up was 19 ± 23.4 months. Persistent motor attenuations occurred in 71.4% of the cohort. MEP was the most sensitive modality (78.6%, 87.5%, and 85.7% sensitivity at POD1, PO-6 weeks, and last follow-up, respectively). The specificity of the D-wave was the most consistent over time (100%, 83.35%, and 90% specificity at the aforementioned time points). The PPV of motor recordings decreased over time (58% vs 33% and 100% vs 0 for tcMEP and D-wave at POD1 and last follow-up, respectively), while their NPV consistently increased (67% vs 89% and 70% vs 100% for tcMEP and D-wave at POD1 and last follow-up, respectively). The diagnostic accuracy of IONM in the resection of IMSCTs varies during the postoperative period. The decrease in the PPV of motor recordings over time suggests that this method is more predictive of short-term rather than long-term neurological deficits. The increasing NPV of motor recordings indicates a higher diagnostic accuracy in the identification of patients who preserve neurological function, albeit with an increased proportion of false-negative alarms for the immediate postoperative period. These variations should be considered in the surgical decision-making process when weighing the risk of resection-associated neurological injury against the implications of incomplete tumor resection.

Spinal Cord Tumor Surgery.

A spinal cord tumor is any tumor involving the spinal cord or immediate surrounding area. Tumors typically are classified as extradural, intradural extramedullary, or intramedullary intradural. Many spinal cord tumor resections attempt to balance tumor removal with preservation of neurologic function. It is important that anesthesiologists be familiar with the common perioperative risks involved in resection of spinal cord tumors as well as how to form an anesthetic plan that takes intraoperative neuromonitoring and patient comorbidities into consideration. Other risks of prolonged spinal tumor resection include postoperative visual loss, acute on chronic pain, and delayed awakening.

Comparison of the safety and outcomes between keyhole surgery and total laminectomy for resection of intradural extramedullary spinal cord tumors

Objective: To compare the safety and outcomes between keyhole surgery and total laminectomy for resection of intradural extramedullary spinal cord tumors. Methods: Retrospectively collected the clinical data of 102 patients with intradural extramedullary spinal cord tumors(≤3 cm) treated by surgery in Department of Orthopedics in Fujian Provincial Hospital from January 2014 to January 2017. Fifty cases underwent the keyhole surgery and the other 52 received total laminectomy. The operation time, volume of intraoperative bleeding, the leaving bed time, the length of postoperative hospital stay, drainage, postoperative complications, intraoperative neuroelectrophysiological monitoring (IONM), preoperative and postoperative visual analogue score (VAS), neck disability index (NDI), Oswestry disability index (ODI), McCormick spinal cord function grading were analyzed and compared between the two groups to evaluate the safety and clinical outcomes. The data of two groups were compared by t, χ(2) or rank sum test. Results: The keyhole group was followed up for (30±15) months and the total laminectomy group was followed up for (45±15) months. All the tumors were completely resected. All the incision healed well and no cerebrospinal fluid leakage occurred. There was no statistically significant differences in baseline data, operation time, the results of IONM, preoperative and 3 months, 6 months, 12 months postoperative VAS, NDI (cervical tumors), ODI (thoracic and lumbar tumors), McCormick spinal cord function grading, tumor recurrence between the two groups (all P>0.05). The keyhole group had less intraoperative bleeding than that in the total laminectomy group ((73±24) ml vs (136±26) ml, t=-12.610, P<0.05), earlier postoperative leaving bed time ((1.4±0.6) d vs (6.5±1.0) d, t=-31.822, P<0.05), and the postoperative hospital stay was shorter ((4.3±0.8) d vs (11.2±2.0) d, t=-22.319, P<0.05), and it was more advantageous in terms of drainage. The VAS, NDI and ODI in the keyhole group improved significantly compared with those in the total laminectomy group 2 weeks post operation (all P<0.05). Conclusion: Compared with the total laminectomy, keyhole surgery is suitable for the treatment of intradural extramedullary spinal cord tumors with small size and limited location, and it is equivalently safe with faster functional recovery.

Risk factor analysis for progressive spinal deformity after resection of intracanal tumors\u2500 a retrospective study of 272 cases

BackgroundProgressive spinal deformity has become a well-recognized complication of intracanal tumors resection. However, the factors affecting post-operative spinal stability remain to be further research. Here, we described the current largest series of risk factors analysis for progressive spinal deformity following resection of intracanal tumors.MethodsWe retrospectively analyzed the medical records of the patients with resection of intracanal tumors between January 2009 and December 2018. All patients who underwent resection of intracanal tumors performed regular postoperative follow-up were identified and included in the study. Clinical, radiological, surgical, histopathological, and follow-up data were collected. The incidence of postoperative progressive kyphosis or scoliosis was calculated. The statistical relationship between postoperative progressive spinal deformity and radiographic, clinical, and surgical variables was assessed by using univariate tests and multivariate logistic regression analysis.ResultsTwo hundred seventy-two patients (mean age 42.56 ± 16.18 years) with median preoperative modified McCormick score of 3 met the inclusion criteria. Among them, 7(2.6%)patients were found to have spinal deformity preoperatively, and the extent of spinal deformity in these 7 patients deteriorated after surgery. 36 (13.2%) were new cases of postoperative progressive deformity. The mean duration of follow-up was 21.8 months (median 14 months, range 6–114 months). In subsequent multivariate logistic regression analysis, age ≤ 18 years (p = 0.027), vertebral levels of tumor involvement (p = 0.019) and preoperative spinal deformity(p = 0.008) was the independent risk factors (p < 0.05), increasing the odds of postoperative progressive spinal deformity by 3.94-, 0.69- and 27.11-fold, respectively.ConclusionsThe incidence of postoperative progressive spinal deformity was 15.8%, mostly in these patients who had younger age (≤18 years), tumors involved in multiple segments and preoperative spinal deformity. The risk factors of postoperative progressive spinal deformity warrants serious reconsideration that when performing resection of spinal cord tumors in these patients with such risk factors, the surgeons should consider conducting follow-ups more closely, and when patients suffering from severe symptoms or gradually increased spinal deformity, surgical spinal fusion may be a more suitable choice to reduce the risk of reoperation and improve the prognosis of patients.

Visual fluorescence combined with laser spectroscopy in surgery for intramedullary spinal cord tumors

Surgical treatment of intramedullary spinal cord tumors is aimed at total resection of tumor with maximum preservation of neurological and functional status. In some cases, intramedullary tumors have unclear dissection plane or gliosis zone. This area is not a tumor and does not require resection. However, it is difficult to distinguish visually intact spinal cord tissue and tumor at the last surgical stages. Thus, we evaluated the effectiveness of fluorescence combined with laser spectroscopy in surgical treatment of intramedullary spinal cord tumors. To determine the effectiveness of visual fluorescence combined with laser spectroscopy in surgery for intramedullary spinal cord tumors. There were 850 patients with intramedullary spinal cord tumors for the period 2001-2019. In 35 cases, intraoperative fluoroscopy with laser spectroscopy were used. All patients underwent a comprehensive pre- and postoperative clinical and instrumental examination (general and neurological status, McCormick grade, spinal cord MRI). Carl Zeiss OPMI Pentero microscope with a fluorescent module was used for intraoperative fluorescence diagnosis. A domestic preparation 5-ALA «ALASENS» (State Research Center NIOPIK, Moscow, Russia) was used for induction of visible fluorescence. Laser spectroscopy was carried out using a LESA-01-BIOSPEK spectrum analyzer. Morphological analysis of intramedullary spinal cord tumors was performed in the neuromorphology laboratory of the Burdenko Neurosurgery Center. Intramedullary anaplastic ependymoma and astrocytoma, as well as conventional ependymoma were characterized by the highest index of 5-ALA accumulation. Intramedullary hemangioblastoma and cavernoma do not accumulate 5-aminolevulinic acid due to morphological structure of these tumors. In particular, there are no cells capable of capturing and processing 5-ALA in these tumors. Sensitivity of visual fluorescence combined with laser spectroscopy varies from 0% to 100% depending on the histological type of tumor: hemangiogblastoma and cavernoma - 0%, low-grade astrocytoma - 70%, high-grade astrocytoma - 80%, ependymoma - 92%, anaplastic ependymoma 100%. Dissection plane is absent in anaplastic ependymoma, high-grade astrocytoma. We often observed gliosis during resection of ependymoma. This tissue is not a part of tumor. Intraoperative metabolic navigation with neurophysiological monitoring are advisable for total tumor resection in case of unclear dissection plane and peritumoral gliosis. Visual fluorescence combined with laser spectroscopy is a perspective method for intraoperative imaging of tumor remnants and total resection of intramedullary spinal cord tumors with minimum risk of neurological impairment.

Meningeal cysts complicated with tethered cord syndrome diagnosed by prenatal ultrasonography: a case report

We reported a case diagnosed with meningeal cysts complicated with tethered cord syndrome based on prenatal ultrasound images at 37+5 gestational weeks, which also showed horseshoe kidney and intrahepatic vascular abnormalities (arteriovenous fistula) in the fetus. The gravida had a precipitate delivery at 39+4 gestational weeks. The anus of this newborn was about 1 cm in front of the normal position. Intrahepatic arteriovenous fistula and horseshoe kidney were detected by neonatal ultrasound and CT scan, and spinal cystic occupying lesion was found by lumbar-sacrum MRI. Intraspinal tumors were removed through spinal canal exploration and spinal cord tumor resection and were confirmed as ependymal cysts by pathological analysis, which was consistent with the prenatal diagnosis. Postoperative changes of lumbar spine was reported by CT scan after the operation. The baby received successful anoplasty when five months old and no abnormal growth or development were found when followed up to one year and eight months old. Raising awareness of tethered cord syndrome can help reduce missed diagnosis and misdiagnosis. Key words: Neural tube defects; Ependyma; Cysts; Ultrasonography, prenatal

Intraoperative neurophysiological mapping & localization of posterior median sulcus during intramedullary spinal cord tumor resection_technical communication

ObjectivesTo assess orthodormic stimulation mapping technique for posterior median sulcus with some variation in parameters from that used in Simon study model. MethodsA Case study of 51 years old female patient diagnosed with intramedullary lesion in the cervical segment, the patient was assigned for laminectomy, tumor exploration and biopsy.We used custom made bipolar stimulator for mapping; it allows variable flexible distance stimulation along the longitudinal axis of the posterior columns and recording from cortical somatosensory evoked potentials SSEPs C3-Fpz and C4-FPz and Cz-FPz channels. We used lateralization rather than phase reversal in localization of posterior median sulcus. ResultsWe were able to identify the functional median sulcus with lateralization to contralateral side rather than phase reversal, the mapping was helpful method to identify PMS, which corresponded to the proposed radiological image's location. ConclusionBipolar orthodormic stimulation can be done using lateralization rather than phase reversal technique. Using Higher Repetition Rate and intensity between 2 and 3 mA can decrease time needed to store averages without compromising evoking the potentials. Stimulation Intensity above 5 to 6 mA can stimulate motor tracts as well in cervical region.