Chronic hyperglycemia and intracranial meningiomas

Meningiomas are among the most common primary tumors of the central nervous system. Previous research into the meningioma histological appearance, genetic markers, transcriptome and epigenetic landscape has revealed that benign meningiomas significantly differ in their glucose metabolism compared to aggressive lesions. However, a correlation between the systemic glucose metabolism and the metabolism of the tumor hasn't yet been found. We hypothesized that chronic levels of glycaemia (approximated with glycated hemoglobin (HbA1c)) are different in patients with aggressive and benign meningiomas. The study encompassed 71 patients with de novo intracranial meningiomas, operated on in three European hospitals, two in Croatia and one in Spain. Our results show that patients with WHO grade 2 meningiomas had significantly higher HbA1c values compared to patients with grade 1 lesions (P = 0.0290). We also found a significant number of patients (19/71; 26.7%) being hyperglycemic, harboring all the risks that such a condition entails. Finally, we found a significant correlation between our patients' age and their preoperative HbA1c levels (P = 0.0008, ρ(rho) = 0.388), suggesting that older meningioma patients are at a higher risk of having their glycaemia severely dysregulated. These findings are especially important considering the current routine and wide-spread use of corticosteroids as anti-edematous treatment. Further research in this area could lead to better understanding of meningiomas and have immediate clinical impact.

Decreased brain volume may be associated with the occurrence of peri-lead edema in Parkinson's disease patients with deep brain stimulation

BACKGROUND

Peri-lead edema (PLE) is a poorly understood complication of deep brain stimulation (DBS), which has been described in patients presenting occasionally with profound and often delayed symptoms with an incidence ranging from 0.4% up to even 100%. Therefore, our study aims to investigate the association of brain and brain compartment volumes on magnetic resonance imaging (MRI) with the occurrence of PLE in Parkinson's disease (PD) patients after DBS implantation in subthalamic nuclei (STN).

METHODS

This retrospective study included 125 consecutive PD patients who underwent STN DBS at the Department of Neurosurgery, Dubrava University Hospital from 2010 to 2022. Qualitative analysis was done on postoperative MRI T2-weighted sequence by two independent observers, marking PLE on midbrain, thalamus, and subcortical levels as mild, moderate, or severe. Quantitative volumetric analysis of brain and brain compartment volumes was conducted using an automated CIVET processing pipeline on preoperative MRI T1 MPRAGE sequences. In addition, observed PLE on individual hemispheres was delineated manually and measured using Analyze 14.0 software.

RESULTS

In our cohort, PLE was observed in 32.17%, mostly bilaterally. Mild PLE was observed in the majority of patients, regardless of the level observed. Age, sex, diabetes, hypertension, vascular disease, and the use of anticoagulant/antiplatelet therapy showed no significant association with the occurrence of PLE. Total grey matter volume showed a significant association with the PLE occurrence (r = -0.22, p = 0.04), as well as cortex volume (r = -0.32, p = 0.0005). Cortical volumes of hemispheres, overall hemisphere volumes, as well as hemisphere/total intracranial volume ratio showed significant association with the PLE occurrence. Furthermore, the volume of the cortex and total grey volume represent moderate indicators, while hemisphere volumes, cortical volumes of hemispheres, and hemisphere/total intracranial volume ratio represent mild to moderate indicators of possible PLE occurrence.

CONCLUSION

The results of our study suggest that the morphometric MRI measurements, as a useful tool, can provide relevant information about the structural status of the brain in patients with PD and represent moderate indicators of possible PLE occurrence. Identifying patients with greater brain atrophy, especially regarding grey matter before DBS implantation, will allow us to estimate the possible postoperative symptoms and intervene in a timely manner. Further studies are needed to confirm our findings and to investigate other potential predictors and risk factors of PLE occurrence.

Bilateral posterior fossa chronic subdural hematoma as a cause of hydrocephalus

Background

Infratentorial chronic subdural hematoma (cSDH) is still a rather elusive neurosurgical entity, which, due to its proximity and likely compression of the cerebellum and brainstem, can lead to devastating consequences. To establish standardized treatment, more studies and reports regarding its therapy are needed. We report a case of a simultaneous unilateral supratentorial and bilateral infratentorial cSDH, with the latter causing hydrocephalus and successfully treated with a bilateral burr-hole trepanation of occipital bone and placement of subdural drains.

Case Description

A 71-year-old man with gait disturbance, Glasgow Coma Scale 12, and a radiologically verified unilateral supratentorial and bilateral cSDH of the posterior fossa causing cerebellum, brainstem, and fourth ventricle compression with obstructive hydrocephalus, underwent surgical evacuation of infratentorial hematoma with a bilateral burr-hole trepanation. The postoperative course was uneventful, with a control head computed tomography scan showing the resolution of the hematoma and hydrocephalus. The patient was discharged with no newly acquired neurological deficits.

Conclusion

Due to a limited number of reports and studies involving infratentorial cSDHs causing hydrocephalus, decision-making and optimal surgical treatment remain unclear. We recommend a timely surgical evacuation of the hematoma if the patient is symptomatic while avoiding placement of external ventricular drainage.

Deep brain stimulation in disorders of consciousness: 10 years of a single center experience

Disorders of consciousness (DoC), namely unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), represent severe conditions with significant consequences for patients and their families. Several studies have reported the regaining of consciousness in such patients using deep brain stimulation (DBS) of subcortical structures or brainstem nuclei. Our study aims to present the 10 years' experience of a single center using DBS as a therapy on a cohort of patients with DoC. Eighty Three consecutive patients were evaluated between 2011 and 2022; entry criteria consisted of neurophysiological and neurological evaluations and neuroimaging examinations. Out of 83, 36 patients were considered candidates for DBS implantation, and 32 patients were implanted: 27 patients had UWS, and five had MCS. The stimulation target was the centromedian-parafascicular complex in the left hemisphere in hypoxic brain lesion or the one better preserved in patients with traumatic brain injury. The level of consciousness was improved in seven patients. Three out of five MCS patients emerged to full awareness, with the ability to interact and communicate. Two of them can live largely independently. Four out of 27 UWS patients showed consciousness improvement with two patients emerging to full awareness, and the other two reaching MCS. In patients with DoC lasting longer than 12 months following traumatic brain injury or 6 months following anoxic-ischemic brain lesion, spontaneous recovery is rare. Thus, DBS of certain thalamic nuclei could be recommended as a treatment option for patients who meet neurological, neurophysiological and neuroimaging criteria, especially in earlier phases, before occurrence of irreversible musculoskeletal changes. Furthermore, we emphasize the importance of cooperation between centers worldwide in studies on the potentials of DBS in treating patients with DoC.

Hemoglobin-Albumin-Lymphocyte-Platelet (HALP) Score as a Predictive Model for the Success of Reconstruction of Head and Neck Defects with Free Microvascular Flaps

Significant advances in reconstructive head and neck surgery with free microvascular flaps have had a positive impact on esthetic outcomes and quality of life. However, complications still occur in some patients. This study investigated the influence of the Hemoglobin, Albumin, Lymphocyte, and Platelet Score (HALP score), an immunonutritive marker, on complications and flap success. The retrospective analysis included 194 patients who underwent reconstruction of head and neck defects with free microvascular flaps. The HALP score correlated strongly with overall complications, including flap necrosis, infection, fistula, and hematoma. Hemoglobin, albumin, lymphocytes, and platelets individually showed associations with specific complications. HALP score was an extremely strong predictor of complications (AUC = 0.85). HALP score may be valuable for assessing patient status and predicting complications in microvascular free-flap reconstruction to allow timely interventions and improve outcomes. Further research is needed to investigate additional predictors and improve postoperative care.

Dysfunctional connectivity as a neurophysiologic mechanism of disorders of consciousness: a systematic review

Introduction

Disorders of consciousness (DOC) has been an object of numbers of research regarding the diagnosis, treatment and prognosis in last few decades. We believe that the DOC could be considered as a disconnection syndrome, although the exact mechanisms are not entirely understood. Moreover, different conceptual frameworks highly influence results interpretation. The aim of this systematic review is to assess the current knowledge regarding neurophysiological mechanisms of DOC and to establish possible influence on future clinical implications and usage.

Methods

We have conducted a systematic review according to PRISMA guidelines through PubMed and Cochrane databases, with studies being selected for inclusion via a set inclusion and exclusion criteria.

Results

Eighty-nine studies were included in this systematic review according to the selected criteria. This includes case studies, randomized controlled trials, controlled clinical trials, and observational studies with no control arms. The total number of DOC patients encompassed in the studies cited in this review is 1,533.

Conclusion

Connectomics and network neuroscience offer quantitative frameworks for analysing dynamic brain connectivity. Functional MRI studies show evidence of abnormal connectivity patterns and whole-brain topological reorganization, primarily affecting sensory-related resting state networks (RSNs), confirmed by EEG studies. As previously described, DOC patients are identified by diminished global information processing, i.e., network integration and increased local information processing, i.e., network segregation. Further studies using effective connectivity measurement tools instead of functional connectivity as well as the standardization of the study process are needed.

Nuclear Epidermal Growth Factor Receptor Overexpression as a Survival Predictor in Oral Squamous Cell Carcinoma

The aim of this study was to determine, by immunohistochemical methods, the expression of nEGFR and markers of cell proliferation (Ki-67), cell cycle (mEGFR, p53, cyclin D1), and tumor stem cells (ABCG2) in 59 pathohistological samples of healthy oral mucosa, 50 oral premalignant changes (leukoplakia and erythroplakia), and 52 oral squamous cell carcinomas (OSCC). An increase in the expression of mEGFR and nEGFR was found with the development of the disease (p < 0.0001). In the group of patients with leukoplakia and erythroplakia, we found a positive correlation between nEGFR and Ki67, p53, cyclin D1, and mEGFR, whereas in the group of patients with OSCC, we found a positive correlation between nEGFR and Ki67, mEGFR (p < 0.05). Tumors without perineural (PNI) invasion had a higher expression of p53 protein than tumors with PNI (p = 0.02). Patients with OSCC and overexpression of nEGFR had shorter overall survival (p = 0.004). The results of this study suggest a potentially important independent role of nEGFR in oral carcinogenesis.

GPi DBS treatment outcome in children with monogenic dystonia: a case series and review of the literature

Introduction

Dystonia is the third most common pediatric movement disorder and is often difficult to treat. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been demonstrated as a safe and effective treatment for genetic dystonia in adolescents and adults. The results of DBS in children are limited to individual cases or case series, although it has been proven to be an effective procedure in carefully selected pediatric cohorts. The aim of our study was to present the treatment outcome for 7- to 9-year-old pediatric patients with disabling monogenic isolated generalized DYT-THAP1 and DYT-KMT2B dystonia after bilateral GPi-DBS.

Patients and results

We present three boys aged <10 years; two siblings with disabling generalized DYT-THAP1 dystonia and a boy with monogenic-complex DYT-KMT2B. Dystonia onset occurred between the ages of 3 and 6. Significantly disabled children were mostly dependent on their parents. Pharmacotherapy was inefficient and patients underwent bilateral GPi-DBS. Clinical signs of dystonia improved significantly in the first month after the implantation and continued to maintain improved motor functions, which were found to have improved further at follow-up. These patients were ambulant without support and included in everyday activities. All patients had significantly lower Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) values, indicating >25% improvement over the first 15 months. However, there was a decline in speech and upper limb function, manifesting with bradylalia, bradykinesia, and dysphonia, which decreased after treatment with trihexyphenidyl.

Conclusion

Although reports of patients with monogenic dystonia, particularly DYT-THAP1, treated with DBS are still scarce, DBS should be considered as an efficient treatment approach in children with pharmacoresistent dystonia, especially with generalized monogenic dystonia and to prevent severe and disabling symptoms that reduce the quality of life, including emotional and social aspects. Patients require an individual approach and parents should be properly informed about expectations and possible outcomes, including relapses and impairments, in addition to DBS responsiveness and related improvements. Furthermore, early genetic diagnosis and the provision of appropriate treatments, including DBS, are mandatory for preventing severe neurologic impairments.

Transient compartmentalization and accelerated volume growth coincide with the expected development of cortical afferents in the human neostriatum

The neostriatum plays a central role in cortico-subcortical circuitry underlying goal-directed behavior. The adult mammalian neostriatum shows chemical and cytoarchitectonic compartmentalization in line with the connectivity. However, it is poorly understood how and when fetal compartmentalization (AChE-rich islands, nonreactive matrix) switches to adult (AChE-poor striosomes, reactive matrix) and how this relates to the ingrowth of corticostriatal afferents. Here, we analyze neostriatal compartments on postmortem human brains from 9 postconceptional week (PCW) to 18 postnatal months (PM), using Nissl staining, histochemical techniques (AChE, PAS-Alcian), immunohistochemistry, stereology, and comparing data with volume-growth of in vivo and in vitro MRI. We find that compartmentalization (C) follows a two-compartment (2-C) pattern around 10PCW and is transformed into a midgestational labyrinth-like 3-C pattern (patches, AChE-nonreactive perimeters, matrix), peaking between 22 and 28PCW during accelerated volume-growth. Finally, compartmentalization resolves perinatally, by the decrease in transient "AChE-clumping," disappearance of AChE-nonreactive, ECM-rich perimeters, and an increase in matrix reactivity. The initial "mature" pattern appears around 9 PM. Therefore, transient, a 3-C pattern and accelerated neostriatal growth coincide with the expected timing of the nonhomogeneous distribution of corticostriatal afferents. The decrease in growth-related AChE activity and transfiguration of corticostriatal terminals are putative mechanisms underlying fetal compartments reorganization. Our findings serve as normative for studying neurodevelopmental disorders.

METEOROLOGICAL VARIABLES ASSOCIATED WITH SUBARACHNOID HEMORRHAGE: A SINGLE CENTER STUDY

Spontaneous subarachnoid hemorrhage (SAH) can occur unexpectedly and independently of the classic risk factors. Several different factors could affect intracranial aneurysm (IA) rupture, such as morphological and hemodynamic factors. The aim of this study was to establish the potential association of meteorological data such as temperature, atmospheric pressure, and humidity, and the onset of clinical symptoms preceding hospital admission of patients with acute SAH due to IA rupture. This retrospective study included 130 consecutive patients admitted for non-traumatic SAH with a determinable onset of SAH symptoms. The effects of meteorological parameters of atmospheric pressure, ambient temperature, and relative air humidity on the day of acute SAH onset and 24 hours prior to the onset of symptoms were recorded and analyzed in each patient. Spearman rank correlation analysis was used to assess the risks of incident SAH on the basis of daily meteorological data. Seasonal incidence of acute SAH showed the peak incidence in winter and a trough in summer, with monthly incidence peak in January and December. The circadian rhythm analysis showed the peak incidence of SAH in the forenoon, followed by the evening. Acute SAH incidence showed moderate positive association with daily atmospheric pressure (p<0.05), while no association was found with ambient temperature and relative air humidity. Our results suggested no significant association of changes in ambient temperature and relative humidity with the risk of SAH. Increases in atmospheric pressure were weakly associated with a higher SAH risk. Additional studies are needed to establish in detail both meteorological and morphological factors important to predict IA rupture and SAH.

TRANSVENOUS APPROACH FOR INDIRECT CAROTID-CAVERNOUS FISTULA USING DETACHABLE COILS: A CASE REPORT AND REVIEW OF TREATMENT OPTIONS

Carotid-cavernous fistula (CCF) is a relatively rare pathology with a low incidence compared with other vascular pathologies. They can be classified based on hemodynamics as low- or high-flow fistulas, and anatomically as direct or indirect fistulas. Anatomy of the shunt somewhat dictates the selection of endovascular treatment, meaning the venous or arterial approach and selection of embolizing materials. Although there is general agreement as to when to access CCF transvenously or transarterialy, which depends on the shunt being direct or indirect, there is no uniform agreement on which occlusion method should be used. Herein, we report a case of an 80-year-old woman treated for indirect CCF using detachable coils. We also provide a brief review of the literature, including recent advances in treatment of said entities. In conclusion, selection of both the approach and material used depends on the operator's experience and preference.

Spontaneous spinal subdural hematoma in COVID-19 patient: Croatian national COVID hospital experience

Background:

Spontaneous spinal subdural hematoma (SSDH) is a rare condition and causes of acute spinal cord compression, with symptoms varying from mild to severe neurological deficit. SSDH could occur as a consequence of posttraumatic, iatrogenic, or spontaneous causes, including underlying arteriovenous malformations, tumors, or coagulation disorder. Due to its rarity, it is difficult to establish standardized treatment. We present a rare case of SSDH in COVID-19 patient and course of treatment in COVID hospital.

Case Description:

A 71-year-old female patient was admitted due to instability, weakness of the left leg, and intensive pain in the upper part of thoracic spine as well as mild respiratory symptoms of COVID-19. She was not on pronounced anticoagulant therapy and her coagulogram at admission was within normal range. MRI revealed acute subdural hematoma at the level C VII to Th III compressing the spinal cord. The patient underwent a decompressive Th I and Th II laminectomy and hematoma evacuation. Post-operative MRI revealed a satisfactory decompression and re-expansion of the spinal cord. COVID-19 symptoms remained mild.

Conclusion:

SSDH represents a neurological emergency, possibly leading to significant deficit and requires urgent recognition and treatment. One of the main difficulties when diagnosing is to consider such condition when there is no history of anticoagulant treatment or previous trauma. Since high incidence of coagulation abnormalities and thromboembolic events was described COVID-19 patients, when considering the pathology of the central nervous system, the bleeding within it due to COVID-19 should be taken into account, in both brain and spine.

Frameless stereotactic brain biopsy and external ventricular drainage placement using the RONNA G4 system

Robot-assisted stereotactic procedures are among the latest technological improvements in neurosurgery. Herein, to the best of our knowledge, we report a first external ventricular drainage (EVD) placement using the RONNA G4 robotic system preformed together with brain biopsy, all in one procedure. A patient was presented with progressive drowsiness, cognitive slowing, poor mobility and incontinent. Magnetic resonance imaging brain scans revealed multicentric process located in the basal ganglia right with extensive vasogenic edema and dilatated ventricular system. Using the RONNAplan software two trajectories were planned: one for brain biopsy on the left side and one for EVD implantation on the right side; the procedures went without complications. The RONNA G4 robotic system is an accurate neurosurgical tool for performing frameless brain biopsies and EVD placement. Further studies are needed in order to enroll a larger patient sample and to calculate the possible placement deviation, and to perform the comparison with other robotic systems.

Cognitive Impact of Deep Brain Stimulation in Parkinson’s Disease Patients: A Systematic Review

Introduction

Parkinson’s disease (PD) patients have a significantly higher risk of developing dementia in later disease stages, leading to severe impairments in quality of life and self-functioning. Questions remain on how deep brain stimulation (DBS) affects cognition, and whether we can individualize therapy and reduce the risk for adverse cognitive effects. Our aim in this systematic review is to assess the current knowledge in the field and determine if the findings could influence clinical practice.

Methods

We have conducted a systematic review according to PRISMA guidelines through MEDLINE and Embase databases, with studies being selected for inclusion via a set inclusion and exclusion criteria.

Results

Sixty-seven studies were included in this systematic review according to the selected criteria. This includes 6 meta-analyses, 18 randomized controlled trials, 17 controlled clinical trials, and 26 observational studies with no control arms. The total number of PD patients encompassed in the studies cited in this review is 3677, not including the meta-analyses.

Conclusion

Cognitive function in PD patients can deteriorate, in most cases mildly, but still impactful to the quality of life. The strongest evidence is present for deterioration in verbal fluency, while inconclusive evidence is still present for executive function, memory, attention and processing speed. Global cognition does not appear to be significantly impacted by DBS, especially if cognitive screening is performed prior to the procedure, as lower baseline cognitive function is connected to poor outcomes. Further randomized controlled studies are required to increase the level of evidence, especially in the case of globus pallidus internus DBS, pedunculopontine nucleus DBS, and the ventral intermediate nucleus of thalamus DBS, and more long-term studies are required for all respective targets.

FORAMEN OVALE AND FORAMEN ROTUNDUM: CHARACTERIZATION OF POSTNATAL DEVELOPMENT

The sphenoid bone development occurs in both prenatal and postnatal periods. Sphenoid bone openings are used as surgical landmarks and are of great importance for neurosurgeons in everyday practice. The aim of this study was to identify morphological characteristics, postnatal development and remodeling, as well as clinical aspect of the sphenoid bone openings and to investigate their relationship and difference in size. The macerated sphenoid bones analyzed in this study were scanned by micro-computed tomography. Areas and distance in-between foramen ovale and foramen rotundum were measured. In addition, different shapes of foramen ovale were described. The most common shape of foramen ovale on both sides was oval, followed by the round, almond and elongated shapes. Modest to strong positive correlations between all foramina and age for the whole sample and both subsamples were presented, except for the right foramen rotundum area in the male subsample, which did not show significant correlation with age. Our study revealed changes in postnatal development and anatomy of foramen ovale and foramen rotundum, primarily in the aspects of size and shape, and should contribute to reducing the risk of damage to neurovascular structures during surgical procedures.

Glycemia and venous thromboembolism in patients with primary brain tumors - A speculative review

Venous thromboembolism (VTE) is a significant public health issue causing severe morbidity and mortality. One of the most vulnerable populations for VTE development are cancer patients. And among them, patients with brain tumors have arguably the highest risk of developing this often fatal complication. Hyperglycemia is a well-known factor which leads to a wide variety of pro-thrombotic changes. In this article, we review the current literature on the topic of VTE in brain tumor patients. We also discuss the known correlation between VTE and glycemia, as well as the importance and frequency of glycemia dysregulation in brain tumor patients. Based on the already well-known importance of glucose metabolism in cancer patients, as well as the previous research of our group, we hypothesize that there is a significant number of brain tumor patients who have chronically elevated glycemia, a fact that so-far hasn't been reported. We argue that these patients carry a significantly higher risk of VTE development and would benefit greatly from strict glycemic control. We present our hypothesis, the ways in which to test it, as well as the possible counter-arguments against it. Our hope is that other investigators will be inspired by our article to continue this type of research, since we consider the topic of VTE in brain tumor patients highly important and urgent, primarily due to its prevalence and severity.

Clinical application of the RONNA G4 system – preliminary validation of 23 robotic frameless brain biopsies

Aims

To report the outcomes of robot-assisted brain biopsies performed using a novel RONNA G4 system. The system was developed by a research group from the Faculty of Mechanical Engineering and Naval Architecture and a team of neurosurgeons from Dubrava University Hospital, University of Zagreb School of Medicine.

Methods

This prospective study included 49 biopsies analyzed during one year: 23 robotic frameless and 26 frame-based Leksell stereotactic biopsies. We analyzed the presenting symptoms, tumor range and location, postoperative complications, pathohistological diagnosis, diagnostic yield, as well as operation and hospitalization duration. The target point error was calculated to assess the accuracy of the RONNA system.

Results

No postoperative mortality, morbidity, or infections were observed. In the frameless robotic biopsy group, only one pathohistological diagnosis was inconclusive. Therefore, the diagnostic yield was 95.6% (22/23), similar to that of the framebased Leksell stereotactic biopsy group (95.1% or 25/26). The average target point error in the frameless robotic biopsy group was 2.15 ± 1.22 mm (range 0.39-5.85).

Conclusion

The RONNA G4 robotic system is a safe and accurate tool for brain biopsy, although further research warrants a larger patient sample, comparison with other robotic systems, and a systematic analysis of the entry and target point errors.

Are We Benign? What Can Wnt Signaling Pathway and Epithelial to Mesenchymal Transition Tell Us about Intracranial Meningioma Progression

Epithelial to mesenchymal transition (EMT), which is characterized by the reduced expression of E-cadherin and increased expression of N-cadherin, plays an important role in the tumor invasion and metastasis. Classical Wnt signaling pathway has a tight link with EMT and it has been shown that nuclear translocation of β-catenin can induce EMT. This research has showed that genes that are involved in cadherin switch, CDH1 and CDH2, play a role in meningioma progression. Increased N-cadherin expression in relation to E-cadherin was recorded. In meningioma, transcription factors SNAIL, SLUG, and TWIST1 demonstrated strong expression in relation to E- and N-cadherin. The expression of SNAIL and SLUG was significantly associated with higher grades (p = 0.001), indicating their role in meningioma progression. Higher grades also recorded an increased expression of total β-catenin followed by an increased expression of its active form (p = 0.000). This research brings the results of genetic and protein analyzes of important molecules that are involved in Wnt and EMT signaling pathways and reveals their role in intracranial meningioma. The results of this study offer guidelines and new markers of progression for future research and reveal new molecular targets of therapeutic interventions.

Frameless stereotactic brain biopsy: A prospective study on robot-assisted brain biopsies performed on 32 patients by using the RONNA G4 system

BACKGROUND

We present a novel robotic neuronavigation system (RONNA G4), used for precise preoperative planning and frameless neuronavigation, developed by a research group from the University of Zagreb and neurosurgeons from the University Hospital Dubrava, Zagreb, Croatia. The aim of study is to provide comprehensive error measurement analysis of the system used for the brain biopsy.

METHODS

Frameless stereotactic robot-assisted biopsies were performed on 32 consecutive patients. Post-operative CT and MRI scans were assessed to precisely measure and calculate target point error (TPE) and entry point error (EPE).

RESULTS

The application accuracy of the RONNA system for TPE was 1.95 ± 1.11 mm, while for EPE was 1.42 ± 0.74 mm. The total diagnostic yield was 96.87%. Linear regression showed statistical significance between the TPE and EPE, and the angle of the trajectory on the bone.

CONCLUSION

The RONNA G4 robotic system is a precise and highly accurate autonomous neurosurgical assistant for performing frameless brain biopsies.

Transient structural MRI patterns correlate with the motor functions in preterm infants

AIM

To explore the relationships between transient structural brain patterns on MRI at preterm and at term-equivalent age (TEA) as a predictor of general movements (GMs) and motor development at 1-year corrected age (CA) in very preterm infants.

METHODS

In this prospective study, 30 very preterm infants (median = 28wks; 16 males) had structural magnetic resonance imaging (MRI) at preterm (median = 31wks + 6d) and at TEA (median = 40wks) and neuromotor assessments. The quality of GMs was assessed by Prechtl's general movements assessment and a detailed analysis of the motor repertoire was performed by calculating a motor optimality score (MOS), both at term age and at 3 months post-term. Motor development at 1-year CA was evaluated with the Infant Motor Profile (IMP). Associations between qualitative MRI findings and neuromotor scores were investigated.

RESULTS

Abnormal GMs and low motor performance at 1-year CA were associated with the poor visibility of transient structural pattern, that is with sagittal strata.

INTERPRETATION

Transient structural MRI pattern, sagittal strata, at preterm age is related to the quality of GMs and later motor development in preterm infants. This transient fetal brain compartment may be considered as a component of neurobiological basis for early neuromotor behavior, as expressed by GMs.

MICROSURGICAL MANAGEMENT OF A RARE INCIDENTAL INTRAVENTRICULAR MENINGIOMA: A CASE REPORT AND RELEVANT LITERATURE REVIEW

Intraventricular meningiomas are rare and make up between 0.5% and 3% of all intracranial meningiomas, representing one of the most challenging tumors in neurosurgery due to their difficult location. Being initially asymptomatic, such tumors usually attain large size before clinical presentation and diagnostic detection. Available literature concerned with their surgical management remains scarce. Herein, we present a case of microsurgical resection of incidental intraventricular meningioma in a 32-year-old female patient who was admitted to the hospital due to the sudden loss of consciousness, retrograde amnesia, and nausea following a head trauma. Routine brain magnetic resonance imaging revealed an irregular expansive formation located in the occipital horn of the right lateral ventricle showing heterogeneous contrast enhancement. The patient underwent right-side temporal osteoplastic craniotomy with total tumor microsurgical resection followed by external ventricular drainage, and recovered fully afterwards. Histopathologic analysis of tumor tissue samples confirmed the tumor as meningioma WHO grade I. Postoperative brain computed tomography confirmed complete tumor resection. In conclusion, intraventricular meningiomas are rather rare extra-axial tumors and may present with various symptoms depending on their size and difficult location. The development of most modern neuroimaging methods offers the opportunity of their precise and accurate diagnosis, better surgical planning, and favorable outcome. Microsurgical gross resection utilizing intraoperative neuromonitoring and cutting-edge neurosurgical armamentarium remains the treatment of choice for these location-challenging and surgically demanding, predominantly benign intracranial tumors.

The Accuracy of Direct Targeting Using Fusion of MR and CT Imaging for Deep Brain Stimulation of the Subthalamic Nucleus in Patients with Parkinson's Disease

INTRODUCTION

 In 33 consecutive patients with Parkinson's disease (PD) undergoing awake deep brain stimulation (DBS) without microelectrode recording (MER), we assessed and validated the precision and accuracy of direct targeting of the subthalamic nucleus (STN) using preoperative magnetic resonance imaging (MRI) and stereotactic computed tomography (CT) image fusion combined with immediate postoperative stereotactic CT and postoperative MRI, and we report on the side effects and clinical results up to 6 months' follow-up.

MATERIALS AND METHODS

 Preoperative nonstereotactic MRI and stereotactic CT images were merged and used for planning the trajectory and final lead position. Immediate postoperative stereotactic CT and postoperative nonstereotactic MRI provided the validation of the final electrode position. Changes in the Unified Parkinson's Disease Rating Scale III (UPDRS III) scores and the levodopa equivalent daily doses (LEDD) and appearance of adverse side effects were assessed.

RESULTS

 The mean Euclidian distance (ED) error between the planned position and the final position of the lead in the left STN was 1.69 ± 0.82 mm and that in the right STN was 2.12 ± 1.00. The individual differences between planned and final position in each of the three coordinates were less than 2 mm. The UPDRS III scores improved by 75% and LEDD decreased by 45%. Few patients experienced complications, such as postoperative infection (n = 1), or unwanted side effects, such as emotional instability (n = 1).

CONCLUSION

 Our results confirm that direct targeting of an STN on stereotactic CT merged with MRI could be a valid method for placement the DBS electrode. The magnitude of our targeting error is comparable with the reported errors when using MER and other direct targeting approaches.

Stereotactic Neuro-Navigation Phantom Designs: A Systematic Review

Diverse stereotactic neuro-navigation systems are used daily in neurosurgery and novel systems are continuously being developed. Prior to clinical implementation of new surgical tools, methods or instruments, in vitro experiments on phantoms should be conducted. A stereotactic neuro-navigation phantom denotes a rigid or deformable structure resembling the cranium with the intracranial area. The use of phantoms is essential for the testing of complete procedures and their workflows, as well as for the final validation of the application accuracy. The aim of this study is to provide a systematic review of stereotactic neuro-navigation phantom designs, to identify their most relevant features, and to identify methodologies for measuring the target point error, the entry point error, and the angular error (α). The literature on phantom designs used for evaluating the accuracy of stereotactic neuro-navigation systems, i.e., robotic navigation systems, stereotactic frames, frameless navigation systems, and aiming devices, was searched. Eligible articles among the articles written in English in the period 2000–2020 were identified through the electronic databases PubMed, IEEE, Web of Science, and Scopus. The majority of phantom designs presented in those articles provide a suitable methodology for measuring the target point error, while there is a lack of objective measurements of the entry point error and angular error. We identified the need for a universal phantom design, which would be compatible with most common imaging techniques (e.g., computed tomography and magnetic resonance imaging) and suitable for simultaneous measurement of the target point, entry point, and angular errors.

LATE ANEURYSM RELAPSE AFTER MICROSURGICAL TREATMENT OF MIDDLE CEREBRAL ARTERY ANEURYSM: A CASE REPORT AND LITERATURE REVIEW OF TREATMENT OPTIONS

Recurrence of intracranial aneurysm after initial microsurgical or endovascular treatment is uncommon. Although the exact etiology remains unknown, recurrent aneurysms may be observed in surgical patients with big and multiple aneurysms, arterial hypertension, non-atherosclerotic cerebrovascular arteriopathies, as well as in those with a familial history of the disease. Such recurrence can occur over a wide period ranging from several months to years after the initial aneurysm treatment. Still, the occurrence delayed by more than 20 years is rather unusual. Herein, we present a case of a 70-year-old female patient who developed late intracranial aneurysm relapse 30 years after successful microsurgical clipping of the middle cerebral artery aneurysm. We also provide a brief review of relevant literature, discussing the etiology and pathophysiology of aneurysm reappearance, as well as different treatment options available. In conclusion, one should always consider the possibility of intracranial aneurysm recurrence regardless of the mode and time of primary surgery. In such a case, a multidisciplinary management approach using flow diverting endovascular techniques is advised in selected patients.

Brain tissue volumes at term-equivalent age are associated with early motor behavior in very preterm infants

Preterm birth is associated with a wide range of adverse developmental outcomes, including sensory, motor, cognitive and language impairments, and behavioral or attention problems. Subtle motor deficits that might emerge in premature infants with no evident or with mild brain injury encompass qualitative and quantitative aspects of motor behavior. This prospective cohort study provided an evaluation of the relationship between brain tissue volumes revealed by magnetic resonance imaging (MRI) at term-equivalent age and motor behavior in infancy in very preterm infants (total number = 40; mean gestational age = 28 weeks + 4 days; mean birth weight = 1190 g) without evident or with mild brain injury. Infants were recruited at birth and assessed at 12 months corrected age using the tool for qualitative and quantitative assessment of motor behavior, infant motor profile. The brain tissue was segmented first using advanced segmentation techniques and the volumes were measured by summing the volumes of all voxels belonging to a particular tissue class. The associations between volumetric brain MRI measures with motor behavior were explored using linear regression analyses. Results showed that larger total brain volumes were associated with higher motor score. Similar relationships were documented for parietal lobe, deep gray matter, and cerebellum volumes. Volumetric quantitative data of brain structures may serve as biomarkers for subtle motor deficits described in very preterm born infants without or with mild brain lesions apparent on MRI.

Hemoglobin A1c in Patients with Glioblastoma-A Preliminary Study

BACKGROUND

Glioblastomas are among the most common primary brain tumors with an abysmal prognosis. The significance of glucose metabolism in glioblastoma cell metabolism and proliferation is well-known. However, a significant correlation between the systemic metabolic status of the patient and the cellular proliferation of the glioblastoma has not yet been established.

METHODS

Our aim was to observe and analyze for a possible correlation between glioblastoma cellular proliferation and patients' glycated hemoglobin (HbA1c) levels as a marker of chronic systemic glycemia. We analyzed the data from 25 patients and compared their Ki-67 values with their preoperative HbA1c values.

RESULTS

We observed a statistically significant correlation (P < 0.03) between chronic glycemia (measured using HbA1c) and the cellular proliferation of glioblastoma (measured by cellular Ki-67 expression).

CONCLUSIONS

These results imply a possible positive correlation between glioblastoma cell proliferation and chronic systemic glycemia, a correlation that, to the best of our knowledge, has not yet been reported. Further research in this area could not only lead to a better understanding of glioblastoma but also have significant clinical applications in treating this devastating disease.

Dynamics of inflammatory factors expression in ischemic brain tissue injury

Ischemic stroke is one of the most common cause of mortality and disability in the modern world. Still, therapeutic options remain modest. Aim of the study was to present dynamics of inflammatory factors expression (C reactive protein, procalcitonin, interleukin 10) in patients after ischemic stroke. Our study included 101 patients divided in thrombolised and nonthrombolised groups. Inflammatory factors concentration in serum was determinate at admission, 24, 48 hours and seven days after the initial onset, while neurological assessment was measured at the admission, 24 hours, seven days and three months after the initial onset using National Institute of Health Stroke Scale and Rankin Scale. Certain pattern was observed in dynamics of inflammatory factors: intensive increase in first and second day after the stroke, followed by decrease till day seven in both groups. Additionally, thrombolised group showed significant neurological improvement. Although well investigated, the role of inflammatory factors in the ischemic stroke still stays controversial. High association of C reactive protein and interleukin 10 values suggest potential prognostic role in patient’s follow-up, while the role of procalcitonin values still remains unclear.

The Dubrava Model-A Novel Approach in Treating Acutely Neurotraumatized Patients in Rural Areas: A Proposal for Management

Introduction Neurotrauma is one of the leading causes of death and disabilities nowadays and represents one of the largest socioeconomic problems in rich countries, as well as developing ones. A satisfying, medically viable, and cost-effective model of managing acutely neurotraumatized patients, especially ones who come from distant and/or rural areas, has yet to be found. Patient outcome after acute neurotrauma depends on many factors of which the possibility of urgent treatment by an experienced specialist team has a crucial role. Here, we present our own way of managing acutely neurotraumatized patients from distant places which is unique in Croatia, the Dubrava model.

Methods We present our 5-year experience cooperating with general hospitals in four neighboring cities (Ĉakovec, Bjelovar, Sisak, and Koprivnica) in managing, operating, and taking care of acutely neurotraumatized patients.

Results More than 300 surgeries have been performed in these hospitals through the Dubrava model. Our experience so far provides encouraging results that this system could also be successfully implemented in other institutions. Furthermore, we recorded an increased number of surgeries each year, as well as a good mutual cooperation with the local general hospitals.

Discussion This trauma managing model is one of a kind in Croatia. We argue that it is not only better for the patients, providing them with better chances of survival, and disability-free recovery, but is also far superior in many ways to the dominant and currently prevalent way of treating these patients in other parts of Croatia.

Conclusion The Dubrava model of treating patients in rural and distant areas is a reliable and proven model with many benefits and as such its implementation should be considered in other institutions as well.

Intraparenchymal supratentorial arachnoid cyst: a case report

Background

Intracranial arachnoid cysts are collections of cerebrospinal fluid within the arachnoid membrane and subarachnoid space of the cisterns and major cerebral fissures that account for about 1% of all intracranial lesions. Expansion of the cyst and compression on surrounding structures may became symptomatic, which reflects its size and anatomic distribution.

Case presentation

Here, we present a very rare case of patient with supratentorial intraparenchymal arachnoid cyst placed in the left frontal lobe without any communication with the subarachnoid space and ventricle and presented with clinical symptoms. The patient underwent fenestration of the lesion and was clinically improved.

Conclusions

Although the etiology and the enlargement mechanism of arachnoid cysts remain unclear, both conservative and surgical treatments are optional. According to size, anatomical location, neuroimaging, and clinical symptoms, an arachnoid cyst should be included in the differential diagnosis of primary intracerebral cysts.

Intracranial Mature Teratoma in an Adult Patient: A Case Report

Introduction : Primary intracranial teratoma is a subtype of germ cell tumors, classified into three subtypes. They occur very rarely, with only several reported individual cases in adults.

Case Description  We present a patient with an intermittent headache in the right frontal region. Magnetic resonance imaging (MRI) revealed a right sided high frontal parasagittal mass that compressed the falx, the right lateral ventricle, as well as the brain parenchyma. Patient underwent surgical treatment. Histopathological analysis described mature teratoma. Four months after the surgical treatment there were no signs of residual intracranial mass or relapse.

Discussion  Primary intracranial teratoma in adults has a nonspecific clinical presentation. MRI reveals a solitary irregular mass with multilocularity and mixed signals derived from different tissues. The patients age, biochemical markers, and patohistological analysis are necessary to confirm the diagnosis.

Conclusion  Teratoma treatment strategy still remains controversial. It includes radical resection whenever possible. Since the residual portion of mature teratoma may contain part of immature or malignant tissue, tumor recurrence after surgical removal is possible. Also, new tumor mass could occur at other sites intracranial after the initial one was removed. Thus, although patients usually recover, they should be followed-up for a long period of time.

Intraspinal calcinosis mimicking intervertebral disc extrusion: A clinical and surgical case report

Background:

Subcutaneous calcinosis is a well-recognized manifestation of systemic sclerosis that usually involves multiple pressure points and may also be found in the paraspinal or intraspinal regions. In this case, intraspinal calcinosis uniquely led to a severe neurological deficit.

Case Description:

A patient with severe systemic sclerosis/calcinosis exhibited left greater than right lower extremity radiculopathy attributed to intraspinal left-sided L4-L5 calcinosis. On examination, the patient exhibited bilateral positive Lasegue signs, distal lower extremity weakness (left greater than right), and bilaterally decreased Achilles responses. When the magnetic resonance imaging (MRI) revealed a significant intracanalicular mass on the left side at the L4-L5 level, the patient underwent a left-sided L4-L5 decompressive laminectomy. The MRI scan 5 years later revealed no recurrence of the calcinosis, and the patient had no residual neurological deficit.

Conclusions:

Spinal calcinosis rarely involves the lumbar spinal canal. Here, a patient with a large left-sided L4-L5 focus of intraspinal calcinosis, mimicking a disc herniation, required a laminectomy to resect the lesion. Lumbar calcinosis should be radiologically evaluated utilizing using X-ray, MRI, and computed tomography studies to adequately document the pathology. Patients, when symptomatic, may require surgical decompression and excision of these lesions.

Primary dural lymphoma mimicking meningioma: a clinical and surgical case report

Introduction: Primary central nervous system lymphoma and its subtype, primary dural lymphoma, are types of non-Hodgkin's lymphoma that only occur in the central nervous system without any dissemination. They are extremely rare cases of extra nodal lymphomas accounting for 1--5% of intracranial tumors. Case report: We present a patient diagnosed with primary dural lymphoma in right frontal brain region who underwent surgical resection. Histopathological analysis revealed diffuse B-type large cell non-Hodgkin lymphoma. Patient underwent four cycles of R-CHOP and intrathecal methotrexate protocol. Six months postoperative, no signs of newly onset infiltration were present. Discussion: Primary dural lymphoma most likely presents with unusual radiological signs, which can easily be mistaken for meningioma, the main differential diagnosis. A thorough immunological, histopathological and clinical patients profile should be conducted in order to establish the certainty of diagnosis. Although there are few treatment options: surgery, radiotherapy or chemotherapy, there is no established treatment protocol.

Quantitative and Qualitative Analysis of Transient Fetal Compartments during Prenatal Human Brain Development

The cerebral wall of the human fetal brain is composed of transient cellular compartments, which show characteristic spatiotemporal relationships with intensity of major neurogenic events (cell proliferation, migration, axonal growth, dendritic differentiation, synaptogenesis, cell death, and myelination). The aim of the present study was to obtain new quantitative data describing volume, surface area, and thickness of transient compartments in the human fetal cerebrum. Forty-four postmortem fetal brains aged 13–40 postconceptional weeks (PCW) were included in this study. High-resolution T1 weighted MR images were acquired on 19 fetal brain hemispheres. MR images were processed using in-house software (MNI-ACE toolbox). Delineation of fetal compartments was performed semi-automatically by co-registration of MRI with histological sections of the same brains, or with the age-matched brains from Zagreb Neuroembryological Collection. Growth trajectories of transient fetal compartments were reconstructed. The composition of telencephalic wall was quantitatively assessed. Between 13 and 25 PCW, when the intensity of neuronal proliferation decreases drastically, the relative volume of proliferative (ventricular and subventricular) compartments showed pronounced decline. In contrast, synapse- and extracellular matrix-rich subplate compartment continued to grow during the first two trimesters, occupying up to 45% of telencephalon and reaching its maximum volume and thickness around 30 PCW. This developmental maximum coincides with a period of intensive growth of long cortico-cortical fibers, which enter and wait in subplate before approaching the cortical plate. Although we did not find significant age related changes in mean thickness of the cortical plate, the volume, gyrification index, and surface area of the cortical plate continued to exponentially grow during the last phases of prenatal development. This cortical expansion coincides developmentally with the transformation of embryonic cortical columns, dendritic differentiation, and ingrowth of axons. These results provide a quantitative description of transient human fetal brain compartments observable with MRI. Moreover, they will improve understanding of structural-functional relationships during brain development, will enable correlation between in vitro/in vivo imaging and fine structural histological studies, and will serve as a reference for study of perinatal brain injuries.

Volumetric analysis of cerebrospinal fluid and brain parenchyma in a patient with hydranencephaly and macrocephaly--case report

The aim of this study was to perform for the first time the intracranial volumetric analysis of cerebrospinal fluid (CSF) and brain parenchyma in the supratentorial and infratentorial space in a 30-year-old female patient with hydranencephaly and macrocephaly. A head scan performed using a 3T magnetic resonance was followed by manual segmentation of the brain parenchyma and CSF on T2 coronal brain sections. The volume of CSF and brain parenchyma was measured separately for the supratentorial and infratentorial space. The total volume of the intracranial space was 3645.5 cm³. In the supratentorial space, the volume of CSF was 3375.2 cm³ and the volume of brain parenchyma was 80.3 cm³. In the infratentorial space, the volume of CSF was 101.3 cm³ and the volume of the brain parenchyma was 88.7 cm³. In the supratentorial space, there was severe malacia of almost all brain parenchyma with no visible remnants of the choroid plexuses. Infratentorial structures of the brainstem and cerebellum were hypoplastic but completely developed. Since our patient had no choroid plexuses in the supratentorial space and no obstruction between dural sinuses and CSF, development of hydrocephalus and macrocephaly cannot be explained by the classic hypothesis of CSF physiology with secretion, unidirectional circulation, and absorption as its basic postulates. However, the origin and turnover of the enormous amount of intracranial CSF volume, at least 10-fold larger than normal, and the mechanisms of macroencephaly development could be elucidated by the new hypothesis of CSF physiology recently published by our research team.