[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.

[The algorithm for surgical treatment of skull base tumors invading the craniovertebral junction].

UNLABELLED: Surgical treatment of skull base tumors invading the craniovertebral junction is a complex medical problem due to a high rate of adverse postoperative outcomes in these patients. AIM: The study aim was to optimize surgical treatment in patients with skull base tumors invading the craniovertebral junction. MATERIAL AND METHODS: A comparative analysis of 2 groups of patients was performed. The study group included 28 patients with skull base and craniovertebral junction chordomas who underwent single-stage surgery, including posterior occipitospondylodesis and tumour resection using the transoral and combined transoral and transnasal approaches, in the period between 2000 and 2015. The control group included 21 patients with the same pathology who underwent microsurgery using the transoral approach without occipitospondylodesis in the period between 1990 and 2009. RESULTS: Most of the patients in both groups were operated on at late disease stages when they presented with gross clinical signs. The use of single-stage occipitospondylodesis and transoral skull base tumor removal significantly (compared to the control group) extends indications for surgical treatment of skull base tumors, which were previously considered unresectable, and provides better results. CONCLUSION: New surgical techniques significantly increase the completeness of tumor resection, decrease the rate of postoperative complications, accelerate the rehabilitation process, and improve the patient's quality of life.

[Modern treatments for degenerative disc diseases of the lumbosacral spine. A literature review]. / Sovremennye metody lecheniia degenerativnykh zabolevanii mezhpozvonkovogo diska. Obzor literatury.

Many researchers consider degenerative diseases of the spine as a pandemic of the XXIst century. Herniated intervertebral discs of the lumbosacral spine occur in 61% of patients with degenerative spine diseases. Of these, 15% of patients have herniated discs at the LII-LIII level, 10% of patients at the LIII-LIV level, and 40% of patients at the LIV-LV and LV-SI levels. A high cost of conservative treatment of degenerative spine disease symptoms and its low efficacy in reducing the intensity and duration of pain necessitate the development of new methods of surgical treatment. In this paper, we analyze the literature data on minimally invasive spine surgery and demonstrate the main advantages of percutaneous endoscopic surgical techniques.

[Endoscopic endonasal removal of the invaginated odontoid process of the C2 vertebra].

UNLABELLED: Pathological processes in the craniovertebral region (clivus, C1 anterior arch, odontoid process and body of the C2 vertebra, i.e. C0-C1-C2 segments) are very difficult to diagnose and treat. The craniovertebral junction instability may develop in the case of a significant lesion of C1-C2 segments. Among diseases causing destruction of the clivus structures and C1-C2 vertebrae and compression of the spinal cord, the following ones are most common: chordoma, giant cell tumor, osteoblastoma, rheumatoid lesion, metastases, platybasia, and basilar impression. These diseases can cause the initial instability of the craniovertebral junction and be accompanied by gross neurological disorders, which complicates the diagnosis and surgical treatment of these patients. MATERIAL AND METHODS: We operated on two patients diagnosed with invagination of the odontoid process of the C2 vertebra. In both cases, one-stage operation was performed that included occipitospondylodesis and endoscopic endonasal removal of the C2 odontoid process. RESULTS: In the postoperative period, partial regression of the neurological symptoms was observed that included an increase in the strength and range of motions in the arms and distal legs, regressed spasticity in the arms and significantly reduced spasticity in the legs, and a significant improvement in all kinds of sensitivity in the arms, legs, and torso. Postoperative liquorrhea was observed in 1 case (patient 2); re-operation to close a CSF fistula was conducted. Later, no signs of liquorrhea were noted. In both cases, control MRI and spiral CT revealed a postoperative bone defect of the C2 odontoid process and clivus, complete decompression of the medulla oblongata and upper cervical spine segments, and no evidence of spinal canal stenosis; the stabilizing system was competent and properly placed. CONCLUSION: The endoscopic endonasal approach, compared to the standard transoral approach, has significant advantages in that the soft palate remains intact, the oropharynx area is less damaged, and the hospitalization and rehabilitation duration is reduced. Also, there are no problems and complications such as possible failure of sutures in the oral cavity and a large wound surface in the oropharynx area. The patient can eat on his own immediately after the operation without the use of a stomach tube (it does not cause any inflammatory complications of the oral cavity). However, the surgical technique of the endoscopic endonasal approach to the C1-C2 segment is more complex than that of transoral surgery and requires the surgeon to be skilled and experienced.

[Intraoperative combined spectroscopy (optical biopsy) of cerebral gliomas]. / Intraoperatsionnaia kombinirovannaia spektroskopiia (opti-cheskaia biopsiia) gliom golovnogo mozga.

Clinical studies have revealed high selectivity of 5-ALA-induced protoporphyrin IX accumulation in different brain tumors. Modern methods of evaluation of tissues visible fluorescence are based on the qualitative analysis of the images. Up-to-date methods of combined spectral analysis allow fulfilling the intraoperative quantitative evaluation of the protoporphyrin IX content, as well as the scattering and absorption properties of a tissue. This paper presents a new method of the simultaneous analysis of hemoglobin concentration in oxygenated and reduced forms, tumor marker concentration (5-ALA-induced PP IX) and a new way to analyze the changes in the scattering properties of the tissues. The method is implemented by splitting the visible spectrum into intervals where hemoglobin and protoporphyrin IX have the characteristic peaks of absorption and fluorescence. The present method shows the dependence of the fluorescence index from the tumor grade. Combined spectroscopy (optical biopsy) can detect the differences between the subtypes of gliomas that are similar in the protoporphyrin IX fluorescence index. This method complements and enhances the diagnostic capabilities of spectroscopy, which is particularly important in the non-fluorescent glioma surgery.

[Working results of the electronic "on-line" version of the Spine Registry for Degenerative Lumbar Spine Diseases and study of its synchronization capacity with the electronic case history]. / Itogi raboty portal'noi versii poiasnichnogo vertebrologicheskogo registra i izuchenie voprosa ego sinkhronizatsii s élektronnoi istoriei bolezni.

AIM: To assess the results of use of lumbar spine on-line registry in 2012 (IV quarter). MATERIAL AND METHODS: The Burdenko Neurosurgery Institute of the Russian Academy of Medical Sciences (RAMS) and the System Analysis Institute of the Russian Academy of Sciences (RAS) have developed an electronic "on-line" portal of the Spine Registry for Degenerative Lumbar Spine Diseases. The data on 1295 retrospective and 145 prospective patients who underwent treatment in Burdenko Neurosurgery Institute, the "AXIS" clinic, Medical Centre of the Bank of Russia, "Marina Spine Clinic" LA, USA and in the Neurosurgery department of Research Institute of Traumatology and Orthopedics, Nizhny Novgorod were analyzed. Since May 2012 to the present time outcomes of 1295 (retrospective group) and 145 (prospective group) patients with Degenerative Lumbar Spine Diseases, which underwent treatment from 2002 to 2012 were entered into online registry and subsequently analyzed. The current study has revealed two problems that need to be discussed. First problem is that the archived information is not sufficient for data base update. The second problem is low activity of many physicians in inputting data into the register. We believe that the solution of these problems lies in the plane of synchronization of on-line registry with electronic medical records. This synchronization between registry and online records will allow studying their joint work. If found to be successful after the development of the other sections of the register they will be added to an already running version as provided by the principles of its work - scalability and extesibility. The results of this work will be profile of vertebrological version of electronic medical records. In the future it could be used in clinics dealing with spine disorders. RESULTS: Since May 2012 the outcomes of 1295 (retrospective group) and 145 (prospective group) patients with Degenerative Lumbar Spine Diseases, who were operated on in Burdenko Neurosurgery Institute (Moscow, Russia), minimally invasive spinal surgery clinic "AXIS" (Moscow, Russia), Medical Centre of The Bank of Russia (Moscow, Russia), "Marina Spine Clinic" (LA, USA) and Neurosurgery department of Research Institute of Traumatology and Orthopedics (Nizhny Novgorod, Russia) from 2002 to 2012 were analyzed. The perspective of this work is development of other parts of spine registry (for cervical and thoracic spine) and improving the outcome assessment process in Russian spinal surgery clinics.

[Photodynamic diagnosis and laser biospectroscopy as an intraoperative guidance in neurosurgery].

Different techniques are used today in neurosurgery for intraoperative navigation, including metabolic guidance using 5-aminolevulinic acid (5-ALA). The article focuses on history of intraoperative photodynamic diagnosis (PDD), mechanisms of 5-ALA action, possibilities of its application in different areas of neurosurgery. In addition to visual assessment of fluorescence, laser biospectroscopy significantly increases the diagnostic value of PDD. Laser biospectroanalysis is described in details, wide perspectives of its application in neurosurgery are demonstrated.

[First experience of photodynamic diagnosis and laser spectroalanysis in surgery of intracranial meningiomas].

Photodynamic diagnosis (PDD) has been actively implemented into neurooncological practice, especially in cerebral gliomas surgery. This paper describes our first experience of PDD combined with laser spectroanalysis in intracranial meningiomas. The study included 21 patients (8 male and 13 female patients, mean age was 58 years, range--between 37 and 74 years) with intracranial meningiomas operated with PDD in Burdenko Neurosurgical Institute between 2008 and 2011. In 14 cases laser spectroanalysis was used. Tumor fluorescence was present in all but one cases (95%). Spectroanalysis demonstrated that peaks of fluorescence varied between 5 and 46 (mean level was 18.5). These data correlated with visual impression of fluorescence and confirmed that meningioma is a tumor with bright fluorescence. Radical removal (Simpson grade I-II) was achieved in 10 cases, subtotal resection was performed in the rest of the patients. Application of PDD and laser spectroanalysis allows gaining complete information about accumulation of photosensibilizer in the tissue. To our opinion, these methods may be the most useful for determination of the borders of dural and bony invasion which directly affects the surgical tactics and degree of radical removal. Further studies are needed to evaluate the influence of PDD and laser spectroanalysis on long-term surgical outcomes.

[Intraoperative fluorescent visualization and laser spectrosopy in intrinsic brain tumor surgery].

Absence of well-defined borders of the glial tumor due to their infiltrative growth is one of the main issues in neurosurgery. A number of methods for intraoperative visualization are available today. The fluorescent metabolic navigation with 5-aminolevulinic acid (5-ALA) combined with quantitative laser spectroscopy is one of the latest technique. In our series of 99 consecutive patients with brain gliomas (WHO Grade I-IV) we found that visible fluorescence was observed in 68% of cases. Additional use of the laser spectroscopy could increase method sensitivity up to 74% due to accumulation of the protoporphyrine IX in nonfluorescense tumors. It was shown that there are some differences in quantitative fluorescence not only within same tumor (glioblastoma) but also in-between low- and high-grade gliomas. Intraoperative fluorescence and laser spectroscopy are effective and very helpful methods of intraoperative imaging in of intrinsic brain tumor surgery.

[Melanotic schwannoma of C(III) spinal root].

We present a case report of the very rare tumor--melanotic schwannoma. Since its first description on 1932 only approximately 100 cases were reported in literature. Due to intensive pigmentation and many features that common for metastatic melanoma and melanotic schwannoma differentiation between these tumors is a challenging and important problem. 61-year-old male patient underwent surgical removal of pigmented extramedullary mass lesion at C2-C3 level. Melanotic schwannoma was diagnosed on the basis of morphological and immunohistochemical signs. Despite positive expression of so-called 'melanoma markers', (HMB-45, S-100, Melana A) cells of melanotic schwannoma also express type IV collagen and laminin which are not characteristic for melanoma. In addition, Ki-67 is very low in melanotic schwannoma, thus it confirms benign character of this tumor. Mentioned immunohistochemical profile allowed to diagnose melanotic schwannoma. It is distinctly clear that prognosis in melanotic schwannoma is incomparably better than in melanoma. Surgical removal is the best treatment option, and postoperative radiation therapy is not necessary as in melanoma.

[Application of robotic assistance in surgical treatment of degenerative disease of lumbosacral spine].

Robotic assistance has gained increasing popularity in spinal surgery recently. Robotic assistance provides higher effectiveness and safety especially in conditions of complicated anatomy. It also enables the novel, previously unavailable surgical techniques, such as GO-Lif for lumbar spine fusion. The aim of the study is to assess the applicability and effectiveness of the robotic assistance in surgical treatment of degenerative lesion of lumbar spine. 16 patients were operated with robotic assistance device (SpineAssist; MAZOR Surgical Technologies, Caesarea, Israel) between August 2009 and February 2010 in Spinal Department of Burdenko Neurosurgical Institute (Moscow, Russia) with degenerative disc disease. Preoperative assessment included MRI, X-rays and high-resolution CT (slice < 1 mm). The CT is essential for preoperative planning using computed work station SpineAssist. The robot was utilized for automated intraoperative positioning of the instruments according to preoperatively planned trajectories. Basic parameters of surgeries were thoroughly recorded: overall surgery time, radiation dose (all manipulations were performed under fluoroscopic control), accuracy of screw placement relative to preoperative planning, which was assessed using postoperative high-resolution CT with 3D reconstruction. Particular interest of the study was focused on the novel fusion technique for lumbar spine: Go-Lif (Guided Oblique Lumbar Interbody Fusion). This fusion modality enables segment fixation with two screws only, it is comparable with pedicular screws in terms of stability, being far less invasive. It may be used standalone or together with TLIF techniques. Robotic assistance enabled optimal screw placement even in complex anatomical cases (thin pedicles and rotational deformity). No implant-related complications were recorded. Surgery time was much longer in first 2 cases, though in further it decreased nearly to conventional (without robot) surgery time. For radiation dose same tendency was observed--in first 2 cases all surgical steps were fluoroscopically controlled, in further cases--only for primary anatomy registration. Based on control CT, accuracy of implant placement with robotic assistance is 1 mm.

[Replacement of lumbosacral intervertebral disks using artificial prostheses: surgical tactics and technique].

The mail goal of the study is to present surgical technique of intervertebral disk replacement using artificial disks and to completely evaluate effectiveness of this modality of treatment of degenerative spine disease using a set of original scales, clinical data and neuroradiological examination. Since 2002 to 2007 14 patients underwent intervertebral disk replacement by artificial prostheses in the Department of Spinal Neurosurgery in Burdenko Neurosurgical Institute (Moscow, Russia). Analysis of results of treatment was performed using multidimensional assessment scales. Potential complications of intervertebral disk replacement by artificial disks are evaluated.

[Prion diseases: current views]. / Prionnye bolezni: sovremennyi vzgliad na problemu.

This is a review of the problem. The above diseases represent a peculiar type of fatal neurodegenerative diseases of man and animals provoker of which is prion--a low molecular anucleinic protein resistant to inactivation. Human prior diseases include fatal familial sleeplessness, Kreutzfeldt-Jakob disease, kuru, Gerstmann-Streussler-Sheinker's syndrome, etc. Prion proteins possess a characteristic capacity to change a tertiary conformation resulting in the formation of a pathological form of protein having infectious properties. Pathogenesis, morphological and clinical manifestations as well as principles of diagnosis and treatment of these diseases are discussed.

Injection form of tissue-engineering construct on the basis of autogenous chondroblasts for regeneration of the cartilaginous tissue.

We present an injection form of tissue-engineering construct on the basis of autogenous human chondroblasts for regeneration of the cartilaginous tissue. A material meeting the requirements for the creation of the injection form of an ITC construct (injectable chondrocyte transplantation) was used as the matrix carrier. The developed construct on the basis of autogenous human chondroblasts and homogenized hemostatic gelatin sponge is now at the stage of complex experimental testing.

Compression asymmetric static experimental model of degenerative disk diseases.

We propose an experimental model of degenerative-dystrophic changes in intervertebral disks of rat tail. The results of X-ray examination and histological studies showed that degenerative changes in the disk tissues caused by experimental compression of intervertebral disks in rat tails are identical to those in humans.