Surgical treatment of glossopharyngeal nerve schwannomas: Results of two-center study (14 patients included) and literature review

Objective: This study is aimed to analyze the outcomes of surgical treatment of glossopharyngeal schwannomas based on pre- and postoperative neurological status assessment. Materials and methods: This paper is a retrospective analysis of examination and surgical treatment of 14 patients who were operated on in two large clinics from 2018 to 2021 inclusive. When analyzing the collected data, gender, age, disease symptoms, tumor size and location, surgical approach, tumor to cranial nerves (CN) ratio, jugular foramen (JF) condition, and tumor removal volume were taken into account. All tumors were divided into groups depending on tumor location relative to the JF. Particular attention was paid to assessing cranial nerves functions. Facial nerve function was assessed as per House-Brackmann Scale (HBS), hearing function as per Gardner-Robertson Scale (GRS). Results: 3 (21.4%) patients had total tumor removal: 2 patients had type A tumors and one had type B tumor. Subtotal resection took place in 7 (50%) cases. In 4 cases, a tumor was partially removed: 3 patients had type D tumors and one had type B tumor. 3 (21.4%) patients had preoperative FN deficit (HBS Grade II) and mild dysfunction. 5 (35.7%) patients had postoperative facial nerve deficit: HBS ІІ, 2; ІІІ, 1; V, 2. Preoperative sensorineural type hearing impairment on the affected side was diagnosed in 13 (92.6%) patients. Before surgery, 6 patients had non-serviceable hearing, which remained at the same level after surgery. None of the patients with grade I or II hearing before surgery had any hearing impairment postoperatively. In 2 (14.3%) cases, hearing improved from grade V to grade III after surgery. 6 (42.9%) patients developed new neurological deficit in the caudal group CN. Postoperative deficit of the caudal group CN occurred in type D tumors in 3 patients, type A tumors 2 patients, and type B tumors one patient. Conclusions: Applying a retrosigmoid approach only makes it possible to achieve total tumor removal in case of type A tumors. To remove other tumor types, it is necessary to select approaches that enable access to the jugular foramen and infratemporal fossa. Intraoperative neurophysiological monitoring is an extremely important tool in glossopharyngeal schwannoma surgery. The most common postoperative complication is a developed or increased deficit of the caudal CN group, which can lead to persistent impairments in the patients’ quality of life. Preservation of the CN VII and VIII function in most cases is a feasible task and shall be ensured as a standard for this pathology.

Microvascular decompression for trigeminal neuralgia, long-term follow-up results and assessment of possible prognostic factors: a single-center retrospective cross-sectional cohort study

Aim: Prognostic factors detection and analysis of long-term results of microvascular decompression for trigeminal neuralgia. Materials and methods. 161 cases of trigeminal neuralgia (TN) treatment by MVD technique without preliminary invasive interventions within 10 years were analyzed. Two blocks of information were designed which included objective case data (8 factors) and patient satisfaction survey (5 questions). Follow-up minimal cut-off was 1 year (median 5.8 years). The primary end point is the proportion of pain free patients and BNI (Barrow Neurological Institute) score at last follow-up. The secondary end point is the assessment of possible risk factors of treatment failure: symptoms duration, decompression type, affected nerve branches, neurovascular conflict visible on MRI, different indications for surgery. Logit-regression analysis was carried out. Significance level was set at p<0,01. Results. Among the studied factors as predictors for pain recurrence all but one failed to reach significance threshold. Conflict on MRI (p=0,231), involved nerve branches (p=0,340), indications for surgery (p=0,659), number of involved vessels (p=0,834), achieved decompression type (p=0,157), venous compression (p=0,143), gender (p=0,150), affected side (p=0,934) did not reach the significance level. For symptoms duration p=0,0012. Conclusions. As a result of multifactorial analysis of study results, the only significant prognostic factor for treatment failure (pain recurrence or worsening of obtained result) was symptoms duration at the time of surgery.

Recurrence rate of sphenoid wing meningiomas and role of peritumoural brain edema: a single center retrospective study

Objective: To evaluate the recurrence rate of the operatively treated sphenoid wing meningiomas (SWMs) in relation to other factors and role of PTBE in recurrence as a prognostic factors in a series of 67 patients. Materials and methods: The magnetic resonance imaging (MRI), and pathology data for 67 patients with SWM, who underwent surgery at Uzhhorod Regional Neurosurgical Center between 2007 and 2021 were examined. The recurrence rate and role of PTBE in recurrence in relation to: gender, age, extend of resection, histopathology, tumor volume, location and time of recurrence were evaluated. Follow-up period ranged from 6 to 168 months (median, 87 months) after surgical resection. Results: In our study, the mean age of patients is 47 years, ranged (20-74), at the average (53.5). Male 16 (23.9%), female 51 (76.1%). Mean tumor volume was (32.8cm3), ranged 4.2cm3-143.7cm3. Edema Index (EI) 1; 27 (40.3%) absent edema, and (EI) >1; in 40 (59.7%) present edema. Recurrence rate was 11 (16.4%) patients, 8 (20.0%) patients with PTBE, as compared to 3 (11.1%) patients without PTBE, (p=0,50). Female (8 patients, 15.7%), male (3 patients, 18.7%). The mean age of recurrence was 50.9 years, ranged (21-75), at the average 52.0 years. The mean age in female was 50.8 years, in male 51.0. Bivariate analysis of simultaneous effect of gender and age on SWM recurrence with logistic regression yield both main effect and interaction effect (β gender=M=7.56±6.44, P=0.24; β age=-0.034±0.031, p=0.28; β interaction term=-0.13±0.12, p=0.26). Out of 11 recurrence cases, (2 cases, 9.5%) with small tumour volume, (5 cases, 15.6%) with medium, (3 cases, 33.3%) with large, and (one case, 20.0%) with giant tumour volume. The effect of tumour volume on recurrence rate is insignificant, χ2=2.42, p=0.49.Location of SWM; the recurrence was in (6 cases, 25.0%) of CM location, (2 cases, 25.0%) of SOM and (3 cases, 11.5%) in lateral SWM, (p=0.19). Pathological grade, in the low grade (Gr.I) 7 recurrence cases (13.0%), as compared to 4cases (44.4%) in atypical Gr II, (p=0.01). Simpson grade, the recurrence rate was; 0% in Gr. I; 13.9% in Gr. II; 20.0% in Gr.III; and 33.3% in Gr. IV and 3 cases had died in the early post op (p<0.05). Conclusion: The factors which had a strong impact on the recurrence rate in our study,; i) pathological grade (Gr. II, atypical type) p=0.01 and ii) Simpson grade (extend of tumor resection, p<0.05), while, PTBE (P=0.50), tumor volume (χ2=2.42, p=0.49) and location (χ2=3.37, p=0.19), are weak and non strong factors for recurrence. However, time of recurrence is shorter in patients with PTBE (W=20.5, p=0.092). WHO Gr. II (Spearman’s p=-0.86, p=0.00063) and negligible for Simpson grade (Spearman’s=-0.15, p=0.66).

Hyperbaric oxygenation therapy in treatment of traumatic spinal cord injury: a pilot study

Spinal cord traumatic injury as resulting persistent movement and sensory disorders is one of the most disabling consequences of traumatic factor impact on the human body. Despite a large number of experimental and clinical studies aimed at developing methods for restoring lost functions, there is no acceptable solution to the problem. One of the promising areas in the treatment and rehabilitation of this category of patients is the use of hyperbaric oxygenation (HBO). Experimental models have shown that HBO has a neuroprotective effect in spinal cord injury, but the results of clinical application of the method are still controversial. Objective: to determine the effectiveness of HBO in the complex therapy of victims with traumatic spinal cord injury and the feasibility of further study of this area. Materials and Methods: Study design is a pilot observational retrospective “case – control”. The database of patients with spinal cord injury who were hospitalized at Romodanov Neurosurgery Institute in the period from 2010 to 2020 were used for the analysis. When selecting a control for each clinical case, the following factors were considered: gender, age, circumstances of injury, type of damage to the osteoligamentous apparatus, level of neurological deficit, degree of damage and compression of the spinal cord, time elapsed from the moment of injury to surgery. 28 "case ‒ control" pairs were analyzed. The main criterion for therapy effectiveness was the change in the functional class according to the ASIA scale. Results. Positive dynamics was registered in 57% of victims, including in the group of patients receiving HBO therapy - in 71%, in the control group - in 43%. HBO therapy in the postoperative period significantly affects the dynamics of regression of neurological disorders (p=0.0295). The odds ratio is 3.333 (95% confidence interval - 1.098‒10.116, p=0.0335). The calculation of the odds ratio, adjusted for additional analyzed factors, showed a more pronounced efficiency - 4.519 (95% confidence interval - 1.279‒15.962, p=0.0192). Conclusions. The obtained results indicate that usage of HBO as a method of complex therapy for traumatic spinal cord injury is promising for further study in order to determine the effectiveness of the method, the optimal timing of treatment initiation in the postoperative period and its duration.

Cognitive evoked potentials in the diagnosis of post-concussion syndrome due to blast mild traumatic brain injury

Hostilities in the East of Ukraine are characterized by the use of new weapons, including rocket artillery, rocket-propelled grenades and landmines. This has led to an increase in the number of victims with blast mild traumatic brain injury (BMTBI) and the need to provide them with effective assistance and rehabilitation. An important task is to improve the BMTBI diagnosis by specifying the objective criteria for structural and functional disorders of the central nervous system. This will improve the prognosis of the course of BMTBI in the injured and the treatment program, including personalized, to prevent the development of persistent neurological deficit. Objective: to investigate the possibilities of the cognitive evoked potentials (CEP) method for the objective diagnosis of cognitive disorders in post-concussion syndrome (PCS) BMTBI. Materials and methods. The study involved 115 men with PCS (main group) and 30 healthy individuals (control group). The cognitive functions of the study participants were studied using the questionnaire "Cicerone". The neurophysiological method for assessing the functional state of the brain involved the registration of CEP, event-related (P300 CEP). Results. The selection of a subgroup of patients with PCS, characterized by a predominance of cognitive impairments, allowed us to trace the relationship between the results of neurophysiological studies with the cognitive indicators of patients with BMTBI. P300 latency indices are inversely proportional to cognitive assessment the questionnaire "Cicerone" and statistically significantly depend on the severity of cognitive impairment. Conclusions. The CEP P300 method can be an effective means of objectifying the degree of cognitive impairment in patients with PCS due to BMTBI.

The impact of extent of resection in surgical outcome of pilomyxoid astrocytoma: a case study

The pilomyxoid astrocytoma (PMA) is a rare glioma that has recently been identified as a separate entity and is frequently found in the hypothalamic region. PMA is a subtype of pilocytic astrocytoma (PA), with clinical, histological, and molecular data indicating a close relationship as well as more aggressive biological behaviour in the former. There is still doubt in surgical outcome of PMA that the extent of resection, independent of location or age, is a key factor of recurrence and subsequent therapeutic choices. However, further study is needed to better understand its behaviour and, as a result, establish a consensus on its management. This research features a 2-year-6-month-old female who sought medical attention after complaining of weight loss for four weeks and vomiting for two weeks prior to her visit to the doctor. She had no additional symptoms. Only bilateral pailledema was found during the physical examination. The magnetic resonance imaging (MRI) scans revealed a tumor in the sellar area with heterogeneous enhancement. The patient had ventriculoperitoneal (VP) shunting followed by partial tumor excision twice (Extent of resection 35 percent followed by 16 percent as total 51 percent). The histology and immunohistochemical investigations revealed typical PMA characteristics. Adjuvant treatment, which included chemotherapy and radiosurgery, was initiated for the patient. She has been asymptomatic for two years and has showed no indications of progression of the disease on follow-up scans.

Dorsal spine intradural extramedullary hemangiopericytoma: a case report

Introduction: Hemangiopericytomas are rare CNS Neoplasms constituting <1% of CNS tumours. They are more commonly seen in cranium than in spine where they present as Intradural extramedullary in location. They rarely metastasize to Lung and Bone.World Health Organization Classification of Tumors of the Central Nervous System (CNS WHO) assigned the combined term solitary fibrous tumor/ hemangiopericytoma (SFT/HPC) to such lesions in 2016 due to their same genetic makeup. Case report: Our case is about a 61-year-old diabetic male who presented with insidious onset, gradually progressive thoracic backache and asymmetric weakness with tightness and numbness of both lower limbs for last 6 months with no sphincter incontinence and bed bound for last 15 days. Clinically he had asymmetric spastic paraparesis of lower limb. His MRI Dorsal spine showed a 1.5 ґ 2 cm heterogeneously contrast enhancing Intradural lesion at D6-D7 compressing the cord from dorsolaterally with extensive cord edema from C5 to L2. Preoperative diagnosis of Meningioma/ Metastasis was made and patient underwentD5-D7 laminectomy and tumour excision. Intraoperative findings, there was no dural attachment, there were multiple tortuous blood vessels overlying greyish pink, fleshy, suckable, highly vascular, capsulated tumor posterolateral to cord. The superior aspect of tumor was adherent to cord with no clear interface. Tumor was seen separate from Left D7 nerve root. Post operatively patient improved symptomatically and neurologically. His HPE was suggestive of Hemangiopericytoma WHO Grade II (IHC markers CD34 and CD 31 was positive and KI 67% index of 10-15%). Patient has been on follow up and planned for metastatic workup. Conclusion: Spinal Hemangiopericytoma are rare disease with nonspecific radiological features making preoperative diagnosis difficult. Differential diagnosis of hemangiopericytoma should be kept in case of atypical and high - grade radiological features. Gross total resection without compromising the neurological status should be the goal to prevent local recurrence. Proper consensus regarding the follow up and adjuvant therapies of spinal Hemangiopericytoma are still lacking.

Model of spinal cord lateral hemi-excision at the lower thoracic level for the tasks of reconstructive and experimental neurosurgery

Purpose. To test the model of spinal cord lateral hemiexcision in young rats. Materials and methods. Animals ‒ male rats (age about 1 month, body weight about 50 g, inbred derivatives of the Wistar line); the number of experimental groups is: 1) lateral spinal cord hemisection at the level of segments about T12–T13 (Sect; n=11); 2) lateral spinal cord hemiexcision about 1 mm long at the similar level (Exc; n=8). Assessment of motor Function Index (FI) and the Spasticity Index (SI) of the paretic hindlimb was carried out using the Basso–Beattie–Bresnahan (BBB) scale and Ashworth scale, respectively, in our technical modifications. The non-inclusion criteria: the BBB score above 9 points of FI for the ipsilateral hindlimb in a week after injury ‒and / or BBB score less than or equal to 14 points of FI of the contralateral hindlimb during a long follow-up period (in general, 2 animals in the Sect group, 3 animals ‒ in the Exc group). Asymptotic differences in the timing of testing between subgroups and groups were revealed during the first three weeks of follow-up. Interpolation reproduction of individual values of FI and SI was used in exceptional cases. The total follow-up period was 5 months. Statistical analysis was performed using the Mann-Whitney U Test, Wilcoxon Matched Pairs Test, Spearman’s Rank Order Correlation. For pathomorphological study, the method of silver impregnation of the spinal cord longitudinal sections of the Exc group animals obtained in 5 months after the simulation of injury was used. Results. One week after injury, the FI in the Sect group was 5.9±1.1 according to BBB points, a statistically significant increase in the FI lasted for the first 3 weeks (p<0.05; Wilcoxon Matched Pairs Test), the FI maximum in the group was 10.1±1.1 BBB points, and the FI value at the end of the study was 9.5±1.0 BBB points. In the Exc group, 1 week after injury, the FI was 0.9±0.5 BBB points, during the next week it reached the actual maximum (1.9±0.7 BBB points), by the end of the 5th month it significantly decreased to 0.8±0.3 BBB points (p<0.05; Wilcoxon Matched Pairs Test). One week after injury, the SI value in the Sect group was 0.3±0.1 points according to Ashworth scale, in the Exc group ‒ 0.7±0.1 Ashworth points, a significant increase (p<0.05; Wilcoxon Matched Pairs Test) in SI in the Sect group was noted during the 2nd week and the 2nd month, in the Exc group ‒ during the 2nd and 6th week, as well as the 3rd and 5th month after injury. The SI final and maximal score for the Sect group was 0.8±0.2 Ashworth points, and for the Exc group ‒ 3.6±0.3 Ashworth points. For both groups, there was no correlation between the mean FI value and a significant positive correlation of the mean SI value with the value of the follow-up period (p<0.05; Spearman’s Rank Order Correlation), as well as the absence of correlation between the mean FI and SI values during the total follow-up period. A significant negative correlation (p<0.05; Spearman’s Rank Order Correlation) between individual FI and SI values was found after 1 and 4 weeks, 3 and 5 months after the injury for the Sect group, as well as after 5, 7, 8 weeks and after 3 and 4 months for the Exc group. At all periods of follow-up, the difference in both FI and SI mean values of both groups was significant (p<0.05; the Mann-Whitney U Test). Conclusions. The studied model of spinal cord injury in young rats is the means of choice for testing solid neural transplantation means for the spinal cord injury restorative treatment. The interpretation of data obtained using the BBB scale on models of lateral half spinal cord injury should be carried out with caution, and the methodology for verifying spasticity requires significant improvement. We recommend that the optimal timing for the FI and SI monitoring after lateral half spinal cord injury is 7 days, 14 days and in 1, 2, 3, 4, 5, 6, and 7 months.

Rigid endoscopic surgery of brainstem cavernous malformation on the cerebral aqueduct. Case report

Cavernous angiomas (malformations) of the brain occur in 0.5% of the population. Most of them are asymptomatic, but due to their anatomical features, namely escape of blood into surrounding tissues, significant neurological symptoms can occur. The deep location of cavernous angiomas in the area of cerebral aqueduct makes surgical intervention difficult. Microsurgical approaches are the gold standard in removal of cavernous angiomas, but they are associated with certain surgical risks in the formation of the surgical corridor. Cavernous malformations in the cerebral aqueduct are a rare subtype. Due to anatomical localization and concomitant obstructive hydrocephalus ІІІ and lateral ventricles, they can be removed by endoscopic frontal transcortical transventricular approach. A 59-year-old patient was diagnosed with cavernous angioma of the brainstem (in the area of cerebral aqueduct) with hemorrhage and the formation of obstructive hydrocephalus ІІІ and lateral ventricles. The operation was performed: removal of the cavernous angioma in the area of cerebral aqueduct by endoscopic frontal transcortical transventricular approach on the right. Additionally, a triventriculocisternostomy was performed. Osteoplastic trepanation with centering at the Kocher’s point in size of 4 × 4 cm and the formation of a free bone flap was performed. The dura mater is cut in an H-shape. Approach to the anterior horn of the right lateral ventricle was performed. An intracerebral retractor was inserted into the anterior horn of the right lateral ventricle. Transforaminal approach to the tuber cinereum was performed - a triventriculocisternostomy was performed. Transforaminal approach to the cerebral aqueduct was performed and the cavernous angioma of the brainstem was removed. In the postoperative period, the patient had a slight deterioration in short-term memory, which regressed 2 weeks after surgery, an increase in oculomotor disorders, in particular persistent diplopia due to moderate paresis of the left oculomotor nerve. Three months after the operation, magnetic resonance imaging of the brain with intravenous contrast enhancement was performed. There are no signs of cavernous angioma. After the operation of frontal transcortical transventricular removal of cavernous angioma in the area of cerebral aqueduct, the compression of the latter was eliminated. Occlusive hydrocephalus regressed, the size of the ventricles decreased. Endoscopic frontal transcortical transventricular approach allows reaching the area of cerebral aqueduct in a less traumatic and minimally invasive manner. This technique is effective due to the low risk of surgical approach complications.

Biomechanical evaluation of the pedicle screw insertion depth and role of cross-link in thoracolumbar junction fracture surgery: a finite element study under compressive loads

Introduction. The thoracolumbar junction is one of the most frequently damaged parts of the human spine when exposed to a traumatic factor. Corpectomy in combination with posterior decompression and restoration of the spinal support function is often performed using an interbody implant and posterior transpedicular stabilization to achieve adequate decompression and stabilization in severe traumatic injuries of this level. The surgery of this type is characterized by significant instability of the operated segment and determines increased requirements for the rigidity and reliability of posterior fixation. We have modeled the situation of a two-level corpectomy with subsequent replacement of bodies with a mesh implant and posterior transpedicular stabilization with 8 screws. Objective. To study the stress-strain state of the thoracolumbar spine model after resection of the Th12-L1 vertebrae with different variants of transpedicular fixation under the influence of a compressive load. Materials and methods. A mathematical finite element model of the human thoracolumbar spine has been developed, the components of which are the Th9 ‒ Th11 and L2-L5 vertebrae (vertebrae Th12-L1 are removed), as well as elements of hardware - interbody support and transpedicular system. Four variants of transpedicular fixation were modeled: using short screws and long screws passing through the cortical layer of anterior wall of vertebral body, as well as two cross links and without them. The stress-strain state of the models was studied under the influence of a vertical compressive distributed load, which was applied to the body of the Th9 vertebra and its articular surfaces. The load value was 350 N, corresponding to the weight of the upper body. Results. d It was found that transpedicular fixation of the thoracolumbar vertebrae with the use of long screws reduces the level of tension in the bone elements of the models. In the area of screw entry into the pedicle of the T10, T11, L2 and L3 vertebral arch, the load when using short screws was 3.1, 1.7, 3.9 and 12.1 MPa, respectively, when using bicortically installed screws - 2.9, 1.8, 3.8 and 10.6 MPa. The addition of two cross-links also reduces the maximum load values in critical areas of the model to a certain extent. In case of short screws combination and two cross-links, the load in these areas was 2.8, 1.7, 3.6 and 11.5 MPa, when using bicortical screws and cross-links - 2.8, 1.6, 3.3 and 9.3 MPa. The study of the stress-strain state of other parts of the model revealed a similar trend. Conclusions. The use of long screws with fixation in the cortical bone of anterior part of the vertebral bodies reduces the level of tension in the bone elements of the models. The use of cross links provides greater rigidity to the transpedicular system, that also reduces the tension in the bone tissue.