Impact of general anaesthesia on parameters of bulbocavernosus reflex

Dysfunction of the pelvic organs in tumor lesions of the spinal cord is up to 20%. Registration of the bulbocavernosus reflex is performed to assess the integrity of the segmental apparatus of the spinal cord. Polymodal neurophysiological monitoring includes registration of the bulbocavernosus reflex during surgery of spinal cord tumors. The effect of the components of general anesthesia on the parameters of the bulbocavernosus reflex varies significantly according to various medical sources. The aim of the work was to compare the effect of inhalation anesthesia (sevoflurane) and total intravenous anesthesia (propofol) on the parameters of the bulbocavernosus reflex in the surgical treatment of spinal cord tumors. Thirty patients with intradural extramedullary and intramedullary tumors of the spinal cord at the level of Th11–S2 vertebrae were included in the study. The amplitude-frequency parameters of the bulbocavernosus reflex and the threshold intensity of stimulation were assessed in the study. The results of the study demonstrate that intraoperative registration of the bulbocavernosus reflex during resection of tumors of the distal spinal cord can be performed both with inhalation and total intravenous anesthesia. A sustained motor response of the bulbocavernosus reflex requires a higher intensity of stimulation with inhalation anesthesia with sevoflurane than with total intravenous anesthesia. If during the operation the depth of propofol's anesthesia increases by 1 mg/kg/h, then it is necessary to increase the current strength during stimulation by 10–11 mA.

Analysis of Factors Influencing the Long-term Outcome in Primary Spinal Cord Tumors: Review of Literature

Introduction Primary spinal cord tumors are amenable to total surgical excision but the outcomes are still diverse. Objective The purpose of this study is to identify the significant factors which influence the long-term outcome of spinal cord tumors. Materials and Methods A total of 84 consecutive spinal cord tumor patients who underwent microsurgical excision during April 2003 to 2014 were retrospectively studied. Patients operated after April 2014 were not considered. Ten factors were taken and correlated with the outcome. Multiple regression analysis was used. Patients were periodically evaluated at 1, 6 months, 1, 2, and 5 years. In 72 cases, postoperative MRI scans were performed. The follow-up period ranged between 5 to 15 years. Results In our study, we had 64 extramedullary tumors and 21 intramedullary tumors with varied pathology. Axial location of the tumour (20.294/0.000), extent of the resection of the tumour (13.827/0.001), preoperative Nurick grade (11.349/0.023), and location of the tumour in the spine with respect to vertebral segments (8.151/0.017) were significant predictive factors. We had good outcomes in 65 cases and poor outcomes in 19 cases. Conclusion Our results show location of the tumor with respect to axial plane and vertebral segments were the main contributing factors. They influence the extent of excision of the spinal cord tumor. Preoperative neurological status is the fourth factor which independently determines the long-term outcome. It is one of the few papers where patients have been followed-up for a long period ranging from 5 to 15 years.

PATH-34. MOLECULAR AND CLINICAL HETEROGENEITY WITHIN SPINAL EPENDYMOMAS

Ependymomas encompass multiple clinically relevant tumor types based on localization, genetic alterations, as well as epigenetic and transcriptomic profiles. Distinct global DNA methylation signatures serve as the most powerful diagnostic tool to distinguish these types. The methylation class of spinal ependymomas (SP-EPN) comprises mostly WHO°II tumors with slow progression and incomplete surgical resection rate. Molecular data of SP-EPN are scarce and clear treatment recommendations are lacking although these neoplasms represent the most common intramedullary tumors in children and adults. The only known recurrent genetic events in SP-EPN are the loss of chromosome 22q and mutations of the NF2 gene. However, data on the frequency of NF2 mutations range from 16 % to 71 % and originate from small series that lack epigenetic or transcriptomic characterization. Furthermore, it remains unclear whether SP-EPN with germline or sporadic NF2 mutation or with NF2 wild type status display clinical and other molecular differences. Finally, the underlying genomic and transcriptomic changes of SP-EPN without NF2 mutations are fully unclear. To provide a comprehensive molecular profile of SP-EPN, we integrated genomic and epigenetic analyses and clinical data of 170 cases. Unsupervised hierarchical clustering and t-SNE analyses of methylation data revealed three distinct molecular SP-EPN subtypes. Of the three subtypes, only subtype 1 and subtype 2 contained tumors with NF2 mutations, either as previously known germline mutations or as sporadic mutations without evidence for a syndromic disease (p< 0.0001). Besides the lack of NF2 mutations, subtype 3 tumors showed a higher frequency of MGMT promoter methylation (p= 0.0015) and occurred in significantly older patients compared to tumors of subtypes 1 and 2 (p= 0.0038). Further investigations such as whole-exome sequencing, copy number variation profiling, gene expression analysis, and histological evaluation are ongoing and will add to the picture of molecular and clinical heterogeneity within SP-EPN.

Spinal Cord Edema in Atypical Cervical Spondylotic Myelopathy--the Facts Behind the Unusual MR Findings: Case Report and Review of the Literature

Purpose We report the case of a young man with a slow progression of cervical spondyloticmyelopathy (CSM). Cervical magnetic resonance imaging (MRI) revealed a mild cervical discbulgingat C5–C6 and an area of atypically enlarged intramedullary high signal intensity extending from C4–C7 (T2-weighted) with contrast enhancement at C5–C6 (T1-weighted). Therefore, neurologic and radiologic diagnoses favored demyelinating diseases. Interference occurred to the diagnosis of CSM.Methods This was a retrospective case study with follow-up examination and MRI at 3 months, 1 year and 2 years postoperatively.Results Thepatient’s symptoms improved immediately postoperatively. The functional result according to the modified Japanese Orthopedic Association (JOA) score improved from 10 to 13 within 3 months. He continued to improve neurologically over the first postoperative year. Two years postoperatively, a T2-weighted MRI showed that the edema signal had disappeared completely , and a fat-saturated T2-weighted MRI showed only slight abnormal signal. The numbness and weakness of the extremities had improved, and his JOA score was 16. Conclusions Spinal cord edema is occasionally seen with CSM. In the case presented, the contrast enhancement was localized at the site of the greatest narrowing of the spinal canal and compression of the spinal cord. This coincidence was the best indicator of a mechanical cause of the spinal cord changes. This feature should increase physician’s confidence in distinguishing CSM from intramedullary tumors and myelitis. Surgical decompression may be beneficial in improving neurologic outcomes.

Optical biopsy: fundamentals and applications in neurosurgery

Currently, there is a significant increase in the incidence of cancer of the central nervous system. Determination of the boundaries of intracerebral and intramedullary tumors is especially difficult. The urgency of the problem of determining the boundaries of astrocytic tumors is due to the peculiarities of their growth along myelinated nerve fibers and vessels, leading to the infiltration of healthy white matter by tumor cells, which affects the high frequency of postoperative relapses. The complexity of surgery for intramedullary tumors of the spinal cord is that the tumor does not always have a clear border and the risk of injury is high due to the smaller size of the operated area compared to the brain. Reliable information regarding the volume of the resected tumor should be obtained by intraoperative imaging. The solution to this problem is implemented mainly in three directions: the use of intraoperative computed tomography, magnetic resonance imaging and ultrasound scanning, and various combinations of these methods. Unfortunately, all these methods of intraoperative diagnostics do not allow real-time examination of tissues in an operating wound and/or do not provide a simultaneous analysis of both structural and metabolic changes. The limitations of intraoperative navigation methods in neurosurgery have led to the relevance of the development of an accurate spectroscopic method for in vivo determination of the content of specific metabolic markers and structural changes accompanying the development of the tumor process in the nervous tissue. Various approaches to intraoperative navigation based on optical spectroscopy are called optical biopsy. In this article, we present the methods and tools developed in recent years for spectroscopic guidance in neurooncology. First of all, this, of course, concerns the analysis of spectral dependences recorded before, during and after tumor removal. We have used such modalities of optical spectroscopy as fluorescence, diffuse reflectance spectroscopy and spontaneous Raman scattering. An equally important issue on the way to increasing the efficiency of tumor resection is the development of new instrumentation; therefore, we have developed a number of new devices, which are a combination of well-known neurosurgical instruments and laser and fiber-optic technologies. Last but not least is the issue of rapid classification of the studied tissues based on the recorded signals, which was solved by us using machine learning methods.

INTRAMEDULLARY THORACIC MENINGIOMA: A RARE CASE REPORT AND REVIEW OF THE LITERATURE

Only a few cases of intramedullary meningiomas in the cervical and thoracic region have been reported in the literature. We present a rare case of intramedullary meningioma in the lower thoracic region. A 68-year-old woman with complaints of back pain, gait disturbance, and paresthesias in both lower extremities for 4 months was admitted to our institution. Initially, she presented with weakness in her legs that gradually deteriorated over time. The patient had been operated on for breast cancer 2 years prior to the onset of current complaints. The neurological examination revealed spastic inferior paraparesis (McCormick grade IV), hypoesthesia below Th10 dermatome, bowel and bladder disturbances. Magnetic resonance imaging of the thoracic spine demonstrated intramedullary tumor that was hypointense on T1 and T2-weighted images but showed homogenous enhancement after gadolinium administration. After gross total resection, the histopathological examination confirmed the diagnosis of atypical intramedullary meningioma. CONCLUSION: The intramedullary meningiomas are extremely rare, but they should not be excluded from the differential diagnosis, especially in cases of intramedullary tumors with homogenous enhancement on magnetic resonance imaging. The best treatment strategy is gross total removal of the tumor.

Dorsal intramedullary giant dermoid tumor

Intramedullary dermoid tumors are rare benign neoplasms that correspond to 1 to 2% of all intramedullary tumors, affecting specially the lumbosacral region. Those tumors are composed of remnants of embryonic tissue derived from the ectoderm, whose walls secretions cause slow growth rate. Despite its benign character, neurological injury comes from the tumor's expansive process and the collateral damage derived from the complete resection of the cyst wall, which can cause hypoesthesia and radicular pain, besides other effects as neuromuscular scoliosis. The primary treatment for intramedullary tumor is resection surgery. The case reported involves an infant with an extensive dorsal intramedullary dermoid tumor without association with spinal dysraphism, presenting clinically complete paraplegia, lower limbs atrophy, hypoesthesia from the T4 level and urinary incontinence. The physical examination revealed upper motor neuron syndrome in the lower limbs, mild cognitive delay and a significant scoliosis. Image exams showed a Cobb angle from T3 to L2 with 115º sitting and 68º with traction, besides a massive expansive intramedullary formation extending from C5 to the T9 plane. The patient underwent extensive cervical and thoracic laminotomy followed by median myelotomy and the resection of the lesion. An arthrodesis treated the secondary vertebral deformity. The postoperative period showed good surgical recovery and the control exams revealed ample resection of the lesion and adequate control of scoliosis with partial maintenance of rotational deformity.

Intradural Pediatric Spinal Tumors: An Overview from Imaging to Novel Molecular Findings

Pediatric spinal tumors are rare and account for 10% of all central nervous system tumors in children. Onset usually occurs with chronic nonspecific symptoms and may depend on the intra- or extradural neoplastic location. Meningiomas, schwannomas, and neurofibromas are the most common intradural-extramedullary lesions, while astrocytomas and ependymomas represent the majority of intramedullary tumors. The new molecular discoveries regarding pediatric spinal cancer currently contribute to the diagnostic and therapeutic processes. Moreover, some familial genetic syndromes can be associated with the development of spinal tumors. Currently, magnetic resonance imaging (MRI) is the standard reference for the evaluation of pediatric spinal tumors. Our aim in this review was to describe the imaging of the most frequent intradural intra/extramedullary pediatric spinal tumors and to investigate the latest molecular findings and genetic syndromes.

Intramedullary Spinal Cystic Lesions Mimicking Cavernoma with Spontaneous Myelum Hemorrhage in Children: A Case Report

Background: Intramedullary spinal masses is a rare yet devastating and challenging. One of the biggest difficulty is to reveal the mass type and feature, thus determine the definitive treatment. Despite its difficulties, many controversies persist regarding diagnosis and management. Case Presentation: We report a case of 6 years old female came with gradual right limb weakness for 1 week before admission. It preceded by neck stiffness and for 2 weeks ago. Radiological examination revealed intradural intramedullary mass suggesting a cavernoma at VC1-C2 and VTh12-L1 level. The histopathological results shows unspecified hematoma. Conclusions: Intramedullary tumors in pediatric population is rare and can mimic any other mass lesion. MRI is the mainstay diagnostic tool of this patient. Complete surgical resection is the main goal of treatment, but the histopathologic features is the most important predictor of the functional outcome.

Intradural Spinal Cord Tumors Surgical Experience with Modified Sheehan Technique

Background: Primary spinal cord tumors are rare neoplasms that lead to significant morbidities. They representing about 2–4% of all tumors that affect the central nervous system. According to their relation to the dura, and spinal cord they are classified into extradural, intradural extramedullary and intradural intramedullary tumors. Magnetic resonance imaging is the radiological investigation of choice for the diagnosis of intradural tumors both intra and extramedullary. Surgical excision is the best treatment modality in the majority of patients. Patients and Methods: This is a retrospective study of thirty patients, fifteen males, and fifteen females suffering spinal cord tumors. Median age at diagnosis 41years. Follow up period range from 6months to 43 months with average 24 months. Neurological assessment of the patients carried out by ASIA (American spinal injury association) scoring. Radiological evaluation occurs through MRI (magnetic resonance imaging) with contrast. Of the studied group seven cases were intradural intramedullary and twenty-three cases were intradural extramedullary. The utilized surgical approach was modified Sheehan technique and all the cases were operated by a single surgeon to avoid the inter surgeon variability. Histopathological assessment was done for the excised specimen for all patients. Results: Thoracic region most affected 53.3%, followed by cervical 23.4%, then lumbar (20%) regions. 76.7% intradural extramedullary, and 23.3% intradural intramedullary. Schwannoma 43.3% and Meningioma (20%) were the most pathology. ASIA group C decreased from 40% to 6.7%, and ASIA group D decreased from 60% to 26.7%, and we got a new ASIA group E 66.7% didn’t exist before surgery. Conclusion: The utilized surgical technique is very effective and safe as we get wide corridor for tumor excision, so increasing the effectiveness of operative microscopy and other operative tools, and improve the surgical outcome as noticed in postoperative neurological status.