Z. A. Barbakadze

Introduction The effectiveness of surgical treatment for cerebral aneurysms is due to the improvement of surgical and anesthetic methods that allow for the exclusion of aneurysms from the blood flow. An important condition for the safe isolation and clipping of an aneurysm is the temporary shutdown of blood flow in the artery, in particular, temporary clipping (TC) of the artery carrying the aneurysm. Intraoperative neurophysiological monitoring (IONM) was proposed to predict ischemic complications in the treatment for intracranial aneurysms using TC. However, data on the results of using IONM in clipping cerebral aneurysms are contradictory. The aim of the study was to evaluate the effectiveness of intraoperative neuromonitoring in the surgical treatment for cerebral aneurysms. Material and methods The examination and surgical treatment of 93 patients with cerebral aneurysms was performed; patients were divided into 2 groups: Group 1 (no IONM) — 48 patients who underwent open clipping of the aneurysm without the use of intraoperative neuromonitoring (control group); Group 2 (IONM) — 45 patients who underwent IONM during surgical treatment for cerebral aneurysms in the internal carotid artery and middle cerebral artery. The treatment outcomes were assessed by the indicators of the radicality of exclusion of the aneurysm from the blood flow, functional outcomes - by the Glasgow Outcome Scale and the Rankin scale. During IONM, transcranial electrical stimulation (TES) was performed, with the impulse being delivered through the bones of the skull from electrodes located on the scalp surface, and motor evoked potentials (MEP) were recorded, direct electrical stimulation of the cerebral cortex (DES-MEP) was performed using a strip electrode laid along the precentral gyrus. After isolating the parent vessel, TC was performed in order to dissect the aneurysm from the surrounding tissues. Results It was found that the use of IONM during blood flow interruption in surgical treatment for cerebral aneurysms was accompanied by a decrease (compared to the group of patients without neuromonitoring) in the number of cases of temporary clipping by 33%, an increase in the total duration of TC by 25%, a decrease in the number of reperfusions by 50%, a decrease in the total duration of reperfusions by 3 times, a decrease in the duration of one ТC session by 10%, and a decrease in the volumetric blood flow through the carrier arteries by 18.1%. At the same time, no significant intergroup differences in systemic hemodynamic parameters were observed. Also, during IONM, there was no decrease in the amplitude of the MEP-TES in 93.3% of patients, the amplitude of evoked potentials did not change in 77.8–91.2% of patients, while the course of the operation changed in 33.3% of patients. In the early postoperative period, in patients who underwent IONM during TC performance, the proportion of patients with a Glasgow Coma Scale score of 14–15 points was 51% higher, and with a score of 9–13 points 8.8 times lower (than in the group without IONM), speech disorders were detected 2.5 times less often, the presence of cerebral ischemia zones was noted 1.8 times less often. Conclusion Thanks to the feedback provided by the use of IONM in real time, the surgeon can always immediately respond to the development of structural damage to the brain, which in turn helps prevent neurological disorders during surgical treatment of cerebral aneurysms. The use of IONM during open clipping of aneurysms allows increasing the number of excellent treatment outcomes by 44%.

Aim. To compare results of surgical treatment of patients with distal aneurysms of the middle cerebral and pericallosal arteries who underwent surgery with frameless neuronavigation and without it. Materials and methods. The study was performed at the N. V. Sklifosovsky Research Institute for Emergency Medicine, Russian Сenter of Neurology and Neurosciences, Moscow City Hospital named after S. S. Yudin between January 1st 2009 and December 31st 2023. Analysis included 45 patients with distal aneurysms of the pericallosal and middle cerebral arteries. Taking into account surgical technique, the patients were divided into 2 groups: the 1st group (n = 21) included patients who underwent surgery with frameless neuronavigation; among them 10 (47.6 %) patients had distal aneurysms of the middle cerebral artery, 11 (52.4 %) patients had distal aneurysms of the pericallosal artery. The 2nd group (n = 24) included patients who underwent surgery without frameless neuronavigation; among them 10 (41.7 %) patients had distal aneurysms of the middle cerebral artery, 14 (58.3 %) patients had distal aneurysms of the pericallosal artery. Results. The use of frameless neuronavigation helps in the search for distal aneurysms during the main stage of the surgery, decreases time between dissection and clipping of a distal aneurysm (p = 0.0001), decreases operative time (р = 0.0001) but requires more time for access planning (p = 0.008). Frameless neuronavigation helps to determine optimal size and location of craniotomy for the most direct and safe trajectory to the distal aneurysm (p = 0.008), decreases the risk of intraoperative injury of the frontal sinus (p = 0.025). Patients, in whom distal aneurysm clipping was performed using frameless navigation, had lower rate of neurologic deficit (p = 0.0001), postoperative (p = 0.025) and systemic (p = 0.005) complications, repeat surgeries (p = 0.002). Conclusion. The use of frameless neuronavigation decreases search time for distal aneurysms and operative time, allows to decrease craniotomy area and prevent intraoperative injury of the frontal sinus, statistically significantly decreases the risk of postoperative neurologic deficit, and improves clinical outcomes.

Background. The problem of pathogenetic treatment of spinal cord injury (SCI) is extremely acute, especially against the background of the growing number of SCI in modern conditions. The world literature widely presents the scientific research on the development and application of regenerative technologies and cell therapy effective for patients with SCI. One of the most promising areas is the use of stem cells. The human umbilical cord blood cells (HUCBCs) is one of the sources for obtaining stem cells having a number of serious advantages such as high efficiency in the patients’ treatment with traumatic lesions of the central nervous system.Aim. To evaluate the safety and primary efficacy of serial systemic (intravenous) administration of allogeneic mononuclear cells of the HUPBC to adult patients with gross neurological deficit because of acute period of severe contusion SCI.Material and methods. Phase I of the SUBSCI I / IIa study included 10 patients (experimental and control groups) with severe SCI (cervical / thoracic / upper lumbar) in the acute period with gross neurological deficit (A / B on the ASIA scale). The conducted treatment included 4 systemic (intravenous) administrations of HUCBCs (allogeneic and compatible by AB0 and Rh factor) within 3 days from the moment of SCI, strictly after the primary surgical intervention. Observation period lasted 12 months after trauma. Safety assessment included the registration of all adverse events (AE) during the observation period with their further classification by severity (CTCAE v. 5.0) and potential connection with the cell therapy. The primary efficacy assessment was the identification of the neurological deficit dynamics (ASIA) – assessment of the restoration degree of motor and sensory functions of the lower extremities during the 1st year.Results and discussion. A total of 419 AEs were detected in 10 patients, but only 2 of them (clinically insignificant) were assessed as probably related to cell therapy, the remaining 417 were not related to therapy. All patients had no signs of immunization to the administered HUCBCs samples. The analysis of the neurological deficit dynamics indicates the reliable restoration of motor functions in patients after cell therapy, compared with the control group.Conclusion. Based on the results obtained, the systemic administration of allogeneic HUPBC, selected without taking into account the HLA system, can be considered as a safe and effective method for treating contusion SCI in the acute period.

Transarticular fixation (TAF) of C₁–C₂ using the F. Magerl method and the Goеl–Harms technique (GHT) are the two most popular ways of forming spondylodesis at the atlantoaxial level. Nevertheless, comparative studies with a high level of evidence have not been published at present.The aim of the study was to conduct a comparative meta‑analysis of the incidence of implant‑associated complications and fusion. The initial search in revealed more than 5,000 abstracts, after applying filters, 202 studies were selected, of which 16 works were included in this study. According to the results of the meta‑analysis, no significant differences were found between the methods of Goel–Harms and F. Magerl in the duration of surgery and intraoperative blood loss, as well as in the frequency of postoperative implant‑associated complications and spinal fusion of C₁–C₂ vertebrae.

Objectives. This study aims to conduct a comparative meta-analysis on the frequency of implant-related complications and fusion rates between screw-rod C1-C2 fusion (Goel-Harms technique, GHT) and transarticular atlantoaxial fusion (Magerl technique, TAF). Methods. Following PRISMA guidelines, we conducted a systematic review. An initial search in the PubMed database yielded over 5,000 abstracts. Inclusion criteria were articles in English involving both TAF and GHT, patient age over 18 years, and studies reporting on fusion incidence and/or implant-related complications, published since January 1987. Results. Sixteen studies met the inclusion criteria. The analysis revealed no significant differences in surgery duration (SMD = -0.21, 95% CI [-0.79, 0.37]) or intraoperative blood loss volume (SMD = 0.095, 95% CI [-0.41, 0.60]). Furthermore, no significant differences were observed between GHT and TAF concerning vertebral artery (VA) injury rate (OR 0.55, 95% CI [0.23 – 1.21]), screw malposition with VA canal perforation (OR 0.77, 95% CI [0.25 – 2.40]), screw malposition in other directions (OR 0.89, 95% CI [0.23-3.44]), C2 radiculopathy (OR 1.3, 95% CI [0.3 – 5.7]), implant failure (OR 0.49, 95% CI [0.16 – 1.46]), and fusion development (OR 1.97, 95% CI [0.93 – 4.16]). Begg's test indicated no publication bias. Conclusion. This meta-analysis found no significant differences between the Goel-Harms and Magerl methods regarding operation duration, intraoperative blood loss, the incidence of postoperative implant-related complications, and C1-C2 fusion rates. Further research, especially studies with a higher evidence level, is vital to develop guidelines for the most effective atlantoaxial stabilization method.

Aim. To present a technique for continuous monitoring of corticospinal tract integrity using an electrode with a dynamic balloon, examine the advantages and disadvantages of the selected and alternative monitoring techniques.Materials and methods. At the 1^st stage, an electrode combined with a dynamic balloon was prepared. At the 2^nd stage, continuous monitoring of the corticospinal tract using direct stimulation of the cortex using ballon grid during the main stage of cerebral surgery was performed. At the 3^rd stage, interpretation of the obtained neurophysiological responses was performed.Results. The presented technique of continuous monitoring of the integrity of the corticospinal tract through direct cortical stimulation using the developed device prevents false response decreases which significantly helps with the interpretation of the obtained results and increases information value of the technique. The described technique is based on the presented clinical observations of intracerebral tumor resection, as well as microsurgical aneurysm clipping using the technique. During surgery, no false decrease of the neurophysiological signal amplitude was observed due to dynamic ballon inflation and maintenance of close contact between the electrode and the surface of the brain. A surgery performed using this technique allowed to achieve a favorable neurological outcome in a patient in the postoperative period.Conclusion. The presented device allows to perform continuous neuromonitoring using direct cortical electrostimulation with a strip electrode at any level of brain retraction. The technique decreases the risk of primary and secondary injury of the corticospinal and corticobulbar tracts which increases safety of neurosurgical intervention and decreases risks of neurological complications.

Background. C1–2 transarticular fixation according to the F. Magerl technique is one of the most reliable methods of C1–2 screw stabilization. An important aspect of the precise placement of implants during transarticular fixation under X‑ray control is the use of correct selection of start‑ and end‑points of the installation trajectory. At certain values of the height and width of C2 isthmus some screw installation trajectories may be accompanied by a zero probability of vertebral artery damage that might be due to the screw malposition.Aim. To evaluate CT morphometric characteristics of the C2 vertebra to assess the possibility of safe C1–2 transarticular fixation.Materials and methods. The analysis performed was based on the data obtained from 7672 patients having admitted with suspected injury to the N.V. Sklifosovsky Research Institute of Emergency Medicine during the period from 01.01.2019 to 31.07.2019. The study involved 6 neurosurgeons and 6 medical doctors of the X‑ray diagnostics department. The measurements were carried out in 2 stages. Each parameter (isthmus height – IsthH, isthmus width – IsthW, lateral mass height – LmH) was measured 2 times. In case of high intraclass correlation, the mean value of the measurements was calculated, which was included in the final analysis.Results. The intraclass correlation coefficient for all measurements approached an excellent correlation values and was 0.852 (95 % CI 0.844–0.860). Morphometric characteristics were calculated basing on data from 795 patients. The IsthH value was 7.45 ± 1.66, IsthW – 8.56 ± 1.48, LmH – 5.56 ± 1.84 mm. In men, the transarticular fixation was significantly more likely to be performed without injury of the vertebral artery (in 66.1 % of cases; χ²‑test, p Conclusions. The results obtained suggest that percutaneous bilateral transarticular fixation with the use of posterior spinolaminar point and middle of the atlas anterior arch as landmarks potentially serves as a method of choice in 88.3 % of patients. Of all patients with normal anatomy of C2 isthmus, men are twice more likely to undergo transarticular fixation without damage of vertebral artery than women, the probability exceeds 66 %. However, the risk of injury of this blood vessel in other patients does not exceed 2.3 %, which is comparable with outcomes of other methods of C1–2 screw stabilization.