[Minimally invasive surgical treatment of extramedullary tumors at the level of craniovertebral junction: experience of the Burdenko Neurosurgical Center]. / Minimal'no invazivnoe khirurgicheskoe lechenie patsientov s ekstramedullyarnymi opukholyami na urovne kraniovertebral'nogo perekhoda: opyt NMITs neirokhirurgii im. akad. N.N. Burdenko.

OBJECTIVE: To describe own experience of treating patients with extramedullary tumors at the level of craniovertebral junction using minimally invasive surgical approaches. MATERIAL AND METHODS: The study included 29 patients who underwent minimally invasive microsurgical resection of extramedullary tumors at the level of craniovertebral junction. We analyzed the main clinical and surgical parameters. RESULTS: Gross total resection was achieved in most patients with high degree of safety. Two patients required redo surgery due to CSF leakage and soft tissue cyst. Mean length of hospital-stay was 7 days. VAS score of pain syndrome at discharge was 2 points and 0 points after 3 months. No significant differences in neurophysiological monitoring indicators were observed (p=0.76). CONCLUSION: Minimally invasive posterior approaches to extramedullary tumors at the level of craniovertebral junction can significantly reduce surgical trauma with equal extent of resection.

[Laser fluorescence spectroscopy and navigation in surgical treatment of spinal tumors: a systematic review]. / Primenenie lazernoi flyuorestsentnoi spektroskopii i navigatsii pri khirurgicheskom lechenii opukholei spinnogo mozga i pozvonochnika: sistematicheskii obzor literatury.

The main problem in microsurgical resection of spinal cord tumors is excessive surgical aggression. The last one often leads to unsatisfactory clinical and neurological outcomes. Laser fluorescence spectroscopy is a modern neurosurgical approach to distinguish tumor boundaries even if standard visible fluorescence techniques are ineffective. OBJECTIVE: To evaluate the effectiveness of laser fluorescence spectroscopy alone or in combination with visual 5-ALA fluorescence for improvement of safety and quality of resection, as well as intraoperative diagnosis. MATERIAL AND METHODS: Searching for literature data was carried out in accordance with the PRISMA recommendations. The authors reviewed articles independently of each other. These data were systematized. RESULTS: Laser fluorescence spectroscopy is valuable to identify fragments of intramedullary ependyomas in 86% of cases, while visual fluorescence only in 81% of cases. Advisability of this technique for low-grade astrocytomas is still unclear and requires further study. Its effectiveness is 87.5% for extramedullary meningiomas. Neuromas do not accumulate 5-ALA. In addition, this method can be used to determine the boundaries of intradural metastatic lesions. CONCLUSION: 5-ALA fluorescence is a safe and useful intraoperative method for identifying tumor tissue and resection margins in patients with intramedullary or infiltrative extramedullary spinal cord tumors. Visual fluorescence combined with laser spectroscopy is a perspective method for intraoperative visualization of tumor remnants. This approach can improve safety and postoperative outcomes while maintaining resection quality.

[Decompression fusion surgery and minimally invasive microsurgical decompression in patients with single-segment lumbar spinal stenosis]. / Sravnitel'nyi analiz rezul'tatov primeneniya metodik dekompressii so stabilizatsiei i minimal'no invazivnoi mikrokhirurgicheskoi dekompressii u patsientov s monosegmentarnym poyasnichnym spinal'nym stenozom.

There are few studies comparing clinical efficacy of decompression/fusion surgery (transforaminal lumbar interbody fusion (TLIF) + transpedicular interbody fusion) and minimally invasive microsurgical decompression (MMD) in patients with single-segment lumbar spinal stenosis. OBJECTIVE: To compare the results of TLIF + transpedicular interbody fusion and MMD in patients with single-segment lumbar spinal stenosis. MATERIAL AND METHODS: A retrospective observational cohort study included medical records of 196 patients (100 (51%) men, 96 (49%) women). Age of patients ranged from 18 to 84 years. Mean postoperative follow-up period was 20.1±6.7 months. Patients were divided into 2 groups: group I (control) included 100 patients who underwent TLIF + transpedicular interbody fusion, group II (study) included 96 patients who underwent MMD. We analyzed pain syndrome and working capacity using visual analogue scale (VAS) and Oswestry Disability Index (ODI), respectively. RESULTS: Analysis of pain syndrome in both groups after 3, 6, 9, 12 and 24 months clearly demonstrated stable relief of pain syndrome (VAS score) in the lower extremities. In group II, VAS score of lower back and leg pain was significantly higher in long-term follow-up period (after 9 months or more) compared to the 1st group (p<0.05). In long-term follow-up period (after 12 months), there was significant decrease in degree of disability (ODI score) in both groups (p<0.001) without between-group differences. We assessed achievement of treatment goal in 12 and 24 months after surgery in both groups. The result was significantly better in the 2nd group. At the same time, some respondents failed to achieve the final clinical goal of treatment in both groups (group I - 8 (12.1%), group II - 2 (3%) patients). CONCLUSION: Analysis of postoperative outcomes in patients with single-segment degenerative lumbar spinal stenosis revealed similar clinical effectiveness of TLIF + transpedicular interbody fusion and MMD regarding decompression quality. However, MMD was associated with less traumatization of paravertebral tissues, blood loss, fewer unwanted phenomena and earlier recovery.

[Intramedullary cervical abscess: a case report and literature review]. / Intramedullyarnyi abstsess sheinogo otdela spinnogo mozga: klinicheskii sluchai i obzor literatury.

Intramedullary abscesses of the spinal cord are the rarest form of infectious lesions of the central nervous system. We report surgical treatment of a patient with intramedullary cervical abscess caused by L. monocytogenes. Features of this case are absence of primary purulent focus and atypical infectious agent. The patient underwent surgical treatment for intramedullary cervical abscess and subsequent antimicrobial therapy. Subtotal regression of neurological symptoms was noted in early postoperative period. The authors emphasize strict collegial decision-making regarding diagnosis of this disease and choice of optimal treatment strategy.

[Minimally invasive microsurgical decompression in patients with monosegmental lumbar spinal stenosis]. / Rezul'taty primeneniya minimal'no invazivnoi mikrokhirurgicheskoi dekompressii u patsientov s monosegmentarnym poyasnichnym stenozom.

Surgical treatment of degenerative lumbar spinal stenosis is an actual problem of modern spinal surgery and orthopedics. OBJECTIVE: To analyze the results of minimally invasive microsurgical decompression (MI-MD) in patients with monosegmental lumbar spinal stenosis. MATERIAL AND METHODS: A retrospective observational cohort study was performed. We analyzed medical records of patients who underwent MI-MD for monosegmental degenerative lumbar spinal stenosis. Clinical and objective results of MI-MD, as well as the types and prevalence of adverse clinical events were studied. RESULTS: The study included 96 medical records (50 (52%) males and 46 (48%) females aged 18-84 years). Analysis of pain in lower back and lower extremities in 3, 6, 9, 12 and 24 months after MI-MD showed a significant decrease of this indicator (p<0.001). There was significant improvement of capacity according to ODI score up to 5-12% in 72.9% of patients in early postoperative period (p=0.055). In delayed postoperative period, we also observed significant improvement of working capacity according to ODI score and gradual decrease in disability index (p<0.001). Adverse clinical events occurred in 6 (6.2%) patients. CONCLUSION: MI-MD is a highly effective surgical method for monosegmental lumbar spinal stenosis with minimal incidence of adverse clinical events.

[Benign extramedullary spinal cord tumors at the level of craniovertebral junction: a systematic review]. / Dobrokachestvennye ekstramedullyarnye opukholi spinnogo mozga na urovne kraniovertebral'nogo perekhoda: sistematicheskii obzor.

Extramedullary spinal cord tumors at the level of craniovertebral junction are a rare group of neoplasms with their own characteristics. Taking into account the peculiarities of clinical course and complex anatomy of craniovertebral complex, these tumors present a complex diagnostic and surgical problem. A systematic review of literature data on epidemiology, clinical picture, diagnostic methods and dorsal minimally invasive methods of surgical treatment of patients with extramedullary spinal cord tumors of craniovertebral junction was performed.

[Degenerative lumbar spine stenosis: minimally invasive microsurgical methods of treatment]. / Degenerativnyi stenoz poyasnichnogo otdela pozvonochnika: kharakteristika minimal'no invazivnykh mikrokhirurgicheskikh metodov lecheniya.

Degenerative lumbar spine stenosis is one of the main causes of chronic pain and radiculopathy in advanced age people. Along with increase in average life expectancy, degenerative lumbar spine stenosis becomes the most common indication for spinal surgery. There is still no consensus regarding the most optimal surgical approach due to the variety of modern surgical methods. In recent years, minimally invasive spinal surgery has become a more advisable alternative to open surgery due to its advanced technical features combined with less soft tissue damage, lower risk of complications and shorter postoperative recovery.

[Intraoperative computed tomography and modern navigation in surgical treatment of spine and spinal cord diseases]. / Opyt primeneniya intraoperatsionnogo spiral'nogo komp'yuternogo tomografa i sovremennoi sistemy navigatsii v khirurgicheskom lechenii zabolevanii pozvonochnika i spinnogo mozga.

Surgical treatment of spine and spinal cord diseases is one of important objectives in modern neurosurgery. Patient safety is a priority in spine and spinal cord surgery. Intraoperative imaging ensures efficacy and safe surgery with and without stabilization, preoperative marking, control of decompression and correct implant placement. Surgical C-arms and intraoperative cone-beam CT scanners are the most widespread in everyday practice. The latest achievement was intraoperative spiral computed tomography. C-arms and CT scanners with intraoperative navigation increase the efficiency and safety of surgical interventions.

[Surgical treatment of spinal cord cavernous malformations]. / Taktika khirurgicheskogo lecheniya kavernoznykh mal'formatsii spinnogo mozga.

Cavernous malformations (CMs) of central nervous system are vascular malformations usually localized in the brain and rarely in the spinal cord. To date, these malformations are well studied. However, some problems of the management of this pathology are still unresolved. This is due to rare localization of intramedullary CMs in the spinal cord and difficult treatment of spinal pathology per se. To date, about 1000 cases of spinal CM are described in the literature. This review is devoted to natural course of disease and postoperative outcomes. These data allow getting a complete picture of modern concepts of the treatment of spinal CMs and formulating the questions requiring further discussion.

[Visual fluorescence combined with laser spectroscopy in surgery for intramedullary spinal cord tumors]. / Vizual'naya fluorestsentsiya v kombinatsii s lazernoi spektroskopiei v khirurgii spinal'nykh intramedullyarnykh opukholei.

BACKGROUND: 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. OBJECTIVE: To determine the effectiveness of visual fluorescence combined with laser spectroscopy in surgery for intramedullary spinal cord tumors. MATERIAL AND METHODS: 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 «ALASENS¼ (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. RESULTS: 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. CONCLUSION: 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.

Rare Cases of IDH1 Mutations in Spinal Cord Astrocytomas.

A low occurrence rate of spinal cord gliomas (4.3% of primary and glial CNS tumors) and the associated difficulties in building statistically significant cohorts of patients considerably slow down the development of effective approaches to the treatment of spinal cord tumors compared to brain tumors. Despite our extensive knowledge regarding IDH mutations in intracranial tumors, mutations of this gene in spinal cord astrocytomas remain poorly understood. In this study, we report on five cases of identified mutations in the IDH1 gene in spinal cord astrocytoma cells, two of which are unique, as they have never been previously described in CNS gliomas.

Molecular Biomarkers of Brain and Spinal Cord Astrocytomas.

Spinal cord astrocytomas are rare diseases of the central nervous system. The localization of these tumors and their infiltrative growth complicate their surgical resection, increase the risk of postoperative complications, and require more careful use of radio- and chemotherapy. The information on the genetic mutations associated with the onset and development of astrocytomas provides a more accurate neoplasm diagnosis and classification. In some cases, it also allows one to determine the optimal methods for treating the neoplasm, as well as to predict the treatment outcomes and the risks of relapse. To date, a number of molecular markers that are associated with brain astrocytomas and possess prognostic value have been identified and described. Due to the significantly lower incidence of spinal cord astrocytomas, the data on similar markers are much more sparse and are presented with a lesser degree of systematization. However, due to the retrospective studies of clinical material that have been actively conducted abroad in recent years, the formation of statistically significant genetic landscapes for various types of tumors, including intradural spinal cord tumors, has begun. In this regard, the purpose of this review is to analyze and systematize the information on the most significant genetic mutations associated with various types of astrocytomas, as well as discuss the prospects for using the corresponding molecular markers for diagnostic and prognostic purposes.

[Resection of a giant sacral schwannoma: case report and literature review]. / Udalenie gigantskoi nevrinomy v oblasti kresttsa: sluchai iz praktiki i obzor literatury.

Neurogenic sacral tumors are extremely rare. In most reported cases, this pathology was associated with neurofibromatosis. Sacral tumors manifest themselves at the stage when the neoplasm volume becomes giant, but these manifestations usually go unnoticed for the patient. Surgical approach to the sacral region is extremely challenging; intimate proximity of tumor capsule to vital organs, vessels, and nerves makes radical surgical treatment of these neoplasms rather difficult. A case report of radical resection of a schwannoma that was destroying the sacrum and continued to grow after radiotherapy is presented in this article.

[Intraoperative video-angiography in surgery for spinal intramedullary cavernous malformations: first experience of its application at the Burdenko Neurosurgical Center]. / Intraoperatsionnaia videoangiografiia v khirurgii intramedulliarnykh kavernoznykh mal'formatsii spinnogo mozga: pervyi opyt ispol'zovaniia v FGAU 'Natsional'nyi meditsinskii issledovatel'skii tsentr neirokhirurgii im. akad. N.N. Burdenko'.

Spinal intramedullary cavernous malformations are a rare vascular pathology of the central nervous system. They account for 3-5% of spinal cord diseases. The clinical picture in patients with cavernous malformations varies from an asymptomatic course to gross neurological deficit in the case of bleeding from a malformation. Due to the lack of reliable methods for predicting the development of bleeding, the need for surgical treatment of asymptomatic patients remains a relevant and open topic for discussion. The goal of surgical treatment of cavernous malformations is to minimize the risk of repeated hemorrhages and gross neurological deficits in patients. Intraoperative indocyanine green video angiography is a promising technique for intraoperative visualization of the size and adherence area of a cavernous malformation to the spinal cord tissue. This increases the radicality of cavernous malformation resection and minimizes intraoperative risks for the patient.