Occipital artery to vertebral artery bypass for treatment of bilateral vertebral artery occlusion with QMRA as an adjunct to diagnostic assessment.

PURPOSE: Stroke, the second leading cause of death globally, often involves ischemia in the vertebrobasilar territory. This condition is underexplored, despite significant morbidity and mortality risks. The purpose of this study is to present a case of occipital artery to V3 segment vertebral artery bypass, emphasizing the role of quantitative magnetic resonance angiography (qMRA) in assessing flow and guiding surgical intervention. METHODS: A 66-year-old man with bilateral vertebral artery occlusion presented acute symptoms. qMRA was employed to evaluate flow dynamics and determine the feasibility of a flow augmentation bypass surgery. The occipital artery to left vertebral artery bypass (OA-to-VA) was performed, utilizing an inverted hockey-stick incision and an antegrade inside-out technique. The patency of the bypass was confirmed using both Doppler probe and Indocyanine green. RESULTS: Postoperative assessments, including computed tomography angiography (CTA) and qMRA, demonstrated the patency of the bypass with improved flow in the basilar artery and left vertebral artery. The patient's condition remained stable postoperatively, with residual peripheral palsy of the left facial nerve. CONCLUSION: In conclusion, the presented case illustrates the efficacy of the OA-to-VA bypass in addressing symptomatic bilateral vertebral artery occlusion. The study underscores the pivotal role of qMRA in pre- and postoperative assessments, providing noninvasive flow quantification for diagnostic considerations and long-term follow-up in patients with vertebrobasilar insufficiency.

Increased macrophage M2/M1 ratio is associated with intracranial aneurysm rupture.

PURPOSE: Intracranial aneurysm (IA) rupture results in one of the most severe forms of stroke, with severe neurological sequelae. Inflammation appears to drive aneurysm formation and progression with macrophages playing a key role in this process. However, less is known about their involvement in aneurysm rupture. This study is aimed at demonstrating how relationship between the M1 (pro-inflammatory) and M2 (reparative) macrophage subtypes affect an aneurysm's structure resulting in its rupture. METHODS: Forty-one saccular aneurysm wall samples were collected during surgery including 13 ruptured and 28 unruptured aneurysm sacs. Structural changes were evaluated using histological staining. Macrophages in the aneurysm wall were quantified and defined as M1 and M2 using HLA-DR and CD163 antibodies. Aneurysm samples were divided into four groups according to the structural changes and the M2/1 ratio. Data were analyzed using the Mann-Whitney U test. RESULTS: This study has demonstrated an association between the severity of structural changes of an aneurysm with inflammatory cell infiltration within its wall and subsequent aneurysm rupture. More severe morphological changes and a significantly higher number of inflammatory cells were observed in ruptured IAs (p < 0.001). There was a prevalence of M2 macrophage subtypes within the wall of ruptured aneurysms (p < 0.001). A subgroup of unruptured IAs with morphological and inflammatory changes similar to ruptured IAs was observed. The common feature of this subgroup was the presence of an intraluminal thrombus. CONCLUSIONS: The degree of inflammatory cell infiltration associated with a shift in macrophage phenotype towards M2 macrophages could play an important role in structural changes of the aneurysm wall leading to its rupture.

Rescue version of a carotid micro-endarterectomy: an ACE-ICA anastomosis with proximal Ica and distal ACE hemoclip obliteration.

Aim of the study: To present our rescue approach of carotid artery occlusion as well as to discuss other possible techniques that can be applied in similar situations.Materials and methods: Two cases from our institution with acute complications during carotid micro-endarterectomy (CEA).Results: Two cases from our institution with acute postoperative complications during CEA that were successfully addressed are presented with imaging and detailed description of the surgical techniques used.Conclusion: CEA are common surgical procedures pursued to achieve revascularization of carotid arteries when occluded partially or fully by an atherosclerotic plaque. As with any surgical procedure, associated complications exist in small percentage of the cases. These can include blood flow limitation due to an insufficient artery wall after atherosclerotic plaque extraction as well as distal kinking of the internal carotid artery. A direct end-to-end ACE-ACI bypass with occlusion of the proximal ACI and distal ACE stump preserves distal flow to the ACI, however the original arteriotomy of ACC must be completely sutured up to the arterial stumps.

Anesthesia type determines risk of cerebral infarction after carotid endarterectomy.

OBJECTIVE: Silent and symptomatic cerebral infarctions occur in up to 34% of patients after carotid endarterectomy (CEA). This prospective study compared the risk of new brain infarctions detected by magnetic resonance imaging (MRI) in patients with internal carotid artery stenosis undergoing CEA with local anesthesia (LA) vs general anesthesia (GA). METHODS: Consecutive patients with internal carotid artery stenosis indicated for CEA were screened at two centers. Patients without contraindication to LA or GA were randomly allocated to the LA or GA group by ZIP code randomization. Brain MRI was performed before and 24 hours after CEA. Neurologic examination was performed before and 24 hours and 30 days after surgery. The occurrence of new infarctions on the control magnetic resonance images, stroke, transient ischemic attack, and other complications was statistically evaluated. RESULTS: Of 210 randomized patients, 105 underwent CEA with LA (67 men; mean age, 68.3 ± 8.1 years) and 105 with GA (70 men; mean age, 63.4 ± 7.5 years). New infarctions were more frequently detected on control magnetic resonance images in patients after CEA under GA compared with LA (17.1% vs 6.7%; P = .031). Stroke or transient ischemic attack occurred within 30 days of CEA in three patients under GA and in two under LA (P = 1.000). There were no significant differences between the two types of anesthesia in terms of the occurrence of other complications (14.3% for GA and 21.0% for LA; P = .277). CONCLUSIONS: The risk of silent brain infarction after CEA as detected by MRI is higher under GA than under LA.

Dynamics of tissue ingrowth in SIKVAV-modified highly superporous PHEMA scaffolds with oriented pores after bridging a spinal cord transection.

While many types of biomaterials have been evaluated in experimental spinal cord injury (SCI) research, little is known about the time-related dynamics of the tissue infiltration of these scaffolds. We analyzed the ingrowth of connective tissue, axons and blood vessels inside the superporous poly (2-hydroxyethyl methacrylate) hydrogel with oriented pores. The hydrogels, either plain or seeded with mesenchymal stem cells (MSCs), were implanted in spinal cord transection at the level of Th8. The animals were sacrificed at days 2, 7, 14, 28, 49 and 6 months after SCI and histologically evaluated. We found that within the first week, the hydrogels were already infiltrated with connective tissue and blood vessels, which remained stable for the next 6 weeks. Axons slowly and gradually infiltrated the hydrogel within the first month, after which the numbers became stable. Six months after SCI we observed rare axons crossing the hydrogel bridge and infiltrating the caudal stump. There was no difference in the tissue infiltration between the plain hydrogels and those seeded with MSCs. We conclude that while connective tissue and blood vessels quickly infiltrate the scaffold within the first week, axons show a rather gradual infiltration over the first month, and this is not facilitated by the presence of MSCs inside the hydrogel pores. Further research which is focused on the permissive micro-environment of the hydrogel scaffold is needed, to promote continuous and long-lasting tissue regeneration across the spinal cord lesion.

Modified Methacrylate Hydrogels Improve Tissue Repair after Spinal Cord Injury.

Methacrylate hydrogels have been extensively used as bridging scaffolds in experimental spinal cord injury (SCI) research. As synthetic materials, they can be modified, which leads to improved bridging of the lesion. Fibronectin, a glycoprotein of the extracellular matrix produced by reactive astrocytes after SCI, is known to promote cell adhesion. We implanted 3 methacrylate hydrogels: a scaffold based on hydroxypropylmethacrylamid (HPMA), 2-hydroxyethylmethacrylate (HEMA) and a HEMA hydrogel with an attached fibronectin (HEMA-Fn) in an experimental model of acute SCI in rats. The animals underwent functional evaluation once a week and the spinal cords were histologically assessed 3 months after hydrogel implantation. We found that both the HPMA and the HEMA-Fn hydrogel scaffolds lead to partial sensory improvement compared to control animals and animals treated with plain HEMA scaffold. The HPMA scaffold showed an increased connective tissue infiltration compared to plain HEMA hydrogels. There was a tendency towards connective tissue infiltration and higher blood vessel ingrowth in the HEMA-Fn scaffold. HPMA hydrogels showed a significantly increased axonal ingrowth compared to HEMA-Fn and plain HEMA; while there were some neurofilaments in the peripheral as well as the central region of the HEMA-Fn scaffold, no neurofilaments were found in plain HEMA hydrogels. In conclusion, HPMA hydrogel as well as the HEMA-Fn scaffold showed better bridging qualities compared to the plain HEMA hydrogel, which resulted in very limited partial sensory improvement.

Chemical angioplasty with spasmolytics for vasospasm after subarachnoid hemorrhage.

BACKGROUND: Clinically symptomatic vasospasm leading to delayed ischemic neurological deficits occurs in up to 30% of patients with subarachnoid hemorrhage (SAH). Vasospasm can result in a serious decline in clinical conditions of patients with SAH, yet the algorithm for vasospasm treatment and prevention remains unclear. Intra-arterial administration of vasodilators is one of the modalities used for vasospasm therapy. METHODS: Over the last 7 years, we have treated 27 female and 7 male patients with vasospasm using intra-arterial administration of either nimodipine or milrinone; all had suffered aneurysm rupture. Of these patients, 28 were treated surgically (clip), and 6 patients had their aneurysm coiled. Spasmolytics were applied from day 2 to day 18 after rupture. RESULTS: Of the 53 procedures, angiographic improvement was documented in 92% of cases with a mean flow velocity decrease of 65 cm/s. Brain metabolism changes were monitored after the procedure. The highest level of immediate clinical improvement was observed in conscious patients with a focal neurological deficit (aphasia, hemiparesis). Overall clinical outcomes (Glasgow outcome scale, GOS) were as follows: GOS 5 (12 patients), GOS 4 (5 patients), GOS 3 (5 patients), GOS 2 (6 patients), and GOS 1 (6 patients). CONCLUSIONS: Intra-arterial administration of spasmolytics is a safe and potent method of vasospasm treatment. It is most effective when applied to conscious patients with a focal deficit. For unconscious patients, its therapeutic benefits are inconclusive. Patients in severe clinical states would further require use of other diagnostic tools such as multimodal brain monitoring to complement vasospasm therapy.

Management of posterior inferior cerebellar artery aneurysms: What factors play the most important role in outcome?

BACKGROUND: Posterior inferior cerebellar artery (PICA) aneurysms are an uncommon, heterogeneous group of aneurysms with poorer clinical outcomes compared to other intracranial aneurysms. We performed a multicenter retrospective study to analyze the outcome in a large series of patients treated with modern microsurgical and endovascular techniques. METHODS: Records of 94 patients treated for PICA aneurysms between 2000 and 2015 at three large tertiary referral centers were retrospectively reviewed. RESULTS: Eighty-three patients met inclusion criteria and of these, two died before treatment, leaving 81 treated patients (43 underwent endovascular and 38 surgical treatment). Among patients treated endovascularly, procedure-related complications occurred in four cases (11.8%). Six patients (19.4%) suffered from complications directly associated with surgery. Recurrences occurred in 0% of surgical and in 16.3% of endovascularly treated patients, requiring treatment. Patients with unruptured asymptomatic aneurysms had good outcomes. In the group of 67 ruptured aneurysms, 16 endovascularly (47.1%) and 15 surgically (48.4%) treated patients had modified Rankin scale (mRS) scores of 3-6. Of patients in poor neurological condition (Hunt & Hess (H&H) IV-V at admission), 84.6% suffered a poor clinical outcome. Fifty percent of patients with distal and 31.9% patients with proximal ruptured PICA aneurysms suffered a poor neurological outcome. CONCLUSIONS: This study of PICA aneurysms demonstrates that results of both treatment modalities are comparable. However, endovascular treatment is associated with higher risks of recurrence, requiring additional treatment. Outcomes were mostly impacted by clinical state at admission.

Carotid-ophthalmic aneurysms-Our results and treatment strategy.

OBJECTIVE: Ophthalmic aneurysms comprise 1.3-5% of all intracranial aneurysms and are the least likely to rupture. On the other hand, they can cause symptoms (visual dysfunction and eye movement palsy) in 18-35% of cases even when unruptured. In our article, we review all the cases of ophthalmic aneurysms treated in our department, discuss treatment methods, and compare our results with those reported in the literature. MATERIAL AND METHODS: In the period 1998-2010, we operated on 37 patients and treated 21 endovascularly. Out of these surgically/endovascularly treated, there were 11/7 asymptomatic, 3/2 unruptured symptomatic, and 23/12 ruptured casess. RESULTS: Surgically treated: Asymptomatic aneurysms were operated on with 9% (1 patient) mortality (due to delayed infection); 87% of patients with ruptured aneurysms improved, 9% remained unchanged, and 4% got worse. Visual dysfunction was restored in 66% of unruptured symptomatic cases (2 patients operated on within 1 month of the start of symptoms). Endovascularly treated. Asymptomatic aneurysms were coiled with 9% (1 patient) mortality and 9% (1 patient) morbidity. Patients with ruptured aneurysms improved in 50% of cases, 25% of patients did not change, 1 patient got worse (12.5%), and 1 patient died (12.5%). Only 1 of 3 coiled patients showed improved 3rd nerve palsy after coiling of an unruptured aneurysm. CONCLUSION: The mortality and morbidity of aneurysms treated in our department, both unruptured and ruptured, were relatively low and comparable with the results presented in the literature. The number of unruptured aneurysms with visual dysfunction was not as high as reported in the literature, but our results correlate with the main conclusion of those studies: to treat those aneurysms surgically when possible and within three months from the start of symptoms.

Coefficient of energy balance, a new parameter for basic investigation of the cerebrospinal fluid.

BACKGROUND: The concentrations of glucose and lactate in cerebrospinal fluid (CSF) provide important information about energy metabolism in the CSF compartment. To improve our understanding of this information we introduced a new parameter resulting from a formula for calculating the fictitious production of adenosine triphosphate, i.e., the coefficient of energy balance (KEB). METHODS: We evaluated cytology, the concentrations of glucose and lactate and the KEB in the CSF of 948 patients, who were divided into five groups. For statistical analysis we used the Kruskal-Wallis test with post-hoc analysis using the Dunn method and multinomial regression analysis. We determined the specificities and sensitivities of the cytological pictures and the KEB. RESULTS: A KEB>28.0 corresponded to normal energy metabolism in the CSF. A KEB<28.0 corresponded to an increased level of anaerobic metabolism in the CSF during inflammation in the CNS. A KEB<10.0 corresponded to a high level of anaerobic metabolism in the CSF during severe inflammation with an oxidative burst of professional phagocytes in the CNS. The KEB parameter increased the specificities of cytological examinations of the CSF in all cases. CONCLUSIONS: The KEB represents an equation for calculating the fictitious average number of ATP molecules produced in the CSF compartment from one molecule of glucose, and we used it successfully as a new parameter for evaluating energy metabolism status in the CSF.

Rupture point is associated with divergent hemodynamics in intracranial aneurysms.

Background: Understanding the risk factors leading to intracranial aneurysm (IA) rupture have still not been fully clarified. They are vital for proper medical guidance of patients harboring unruptured IAs. Clarifying the hemodynamics associated with the point of rupture could help could provide useful information about some of the risk factors. Thus far, few studies have studied this issue with often diverging conclusions. Methods: We identified a point of rupture in patients operated for an IAs during surgery, using a combination of preoperative computed tomography (CT) and computed tomography angiography (CTA). Hemodynamic parameters were calculated both for the aneurysm sac as a whole and the point of rupture. In two cases, the results of CFD were compared with those of the experiment using particle image velocimetry (PIV). Results: We were able to identify 6 aneurysms with a well-demarcated point of rupture. In four aneurysms, the rupture point was near the vortex with low wall shear stress (WSS) and high oscillatory shear index (OSI). In one case, the rupture point was in the flow jet with high WSS. In the last case, the rupture point was in the significant bleb and no specific hemodynamic parameters were found. The CFD results were verified in the PIV part of the study. Conclusion: Our study shows that different hemodynamic scenarios are associated with the site of IA rupture. The numerical simulations were confirmed by laboratory models. This study further supports the hypothesis that various pathological pathways may lead to aneurysm wall damage resulting in its rupture.

Open Microsurgical Cerebral Aneurysm Treatment After Failed Endovascular Therapy: An Evaluation of Aneurysm Treatment Frequencies in All Neurovascular Centers Across Austria and the Czech Republic Over 20 Years.

BACKGROUND AND OBJECTIVES: Endovascular treatment of cerebral aneurysms has tremendously advanced over the past decades. Nevertheless, aneurysm residual and recurrence remain challenges after embolization. The objective of this study was to elucidate the portion of embolized aneurysms requiring open surgery and evaluate whether newer endovascular treatments have changed the need for open surgery after failed embolization. METHODS: All 15 cerebrovascular centers in Austria and the Czech Republic provided overall aneurysm treatment frequency data and retrospectively reviewed consecutive cerebral aneurysms treated with open surgical treatment after failure of embolization from 2000 to 2022. All endovascular modalities were included. RESULTS: On average, 1362 aneurysms were treated annually in the 2 countries. The incidence increased from 0.006% in 2005 to 0.008% in 2020 in the overall population. Open surgery after failed endovascular intervention was necessary in 128 aneurysms (0.8%), a proportion that remained constant over time. Subarachnoid hemorrhage was the initial presentation in 70.3% of aneurysms. The most common location was the anterior communicating artery region (40.6%), followed by the middle cerebral artery (25.0%). The median diameter was 6 mm (2-32). Initial endovascular treatment included coiling (107 aneurysms), balloon-assist (10), stent-assist (4), intrasaccular device (3), flow diversion (2), and others (2). Complete occlusion after initial embolization was recorded in 40.6%. Seventy-one percent of aneurysms were operated within 3 years after embolization. In 7%, the indication for surgery was (re-)rupture and, in 88.3%, reperfusion. Device removal was performed in 16.4%. Symptomatic intraoperative and postoperative complications occurred in 10.2%. Complete aneurysm occlusion after open surgery was achieved in 94%. CONCLUSION: Open surgery remains a rare indication for cerebral aneurysms after failed endovascular embolization even in the age of novel endovascular technology, such as flow diverters and intrasaccular devices. Regardless, it is mostly performed for ruptured aneurysms initially treated with primary coiling that are in the anterior circulation.

Distant white-matter diffusion changes caused by tumor growth.

OBJECTIVES: Various reports have suggested that the involvement of normal-looking white matter with tumors is not limited to just signal abnormalities detectable on conventional imaging. Thus, the purpose of this study was to investigate the distant effects of glioblastomas and metastases on white matter using diffusion tensor imaging (DTI). MATERIALS AND METHODS: Data for 21 patients harboring a glioblastoma (n=12) or a metastasis (n=9) located at a distance of smaller or equal to 10mm from a DTI-based reconstruction of the pyramidal tract were analyzed, using regions of interest (ROIs) placed along the pyramidal tracts in the cerebral peduncle distant (>15 mm) from the tumor. RESULTS: For the whole study population, fractional anisotropy (FA) was significantly lower on the side ipsilateral to the tumor (P<0.001), a difference that was also observed in the glioblastoma and metastasis subgroups. The trace value was significantly higher on the ipsilateral side in the whole population and metastasis subgroup, but not in the glioblastoma subgroup. The decrease in FA and the trace value increase were significant in a subgroup of patients with motor deficits, but not in those without such deficits. CONCLUSION: Hemispheric glioblastomas and metastases located close to the pyramidal tract induce diffusion changes in the tract that are observable at a distance of greater than 15 mm from the tumor border in the absence of T2 signal changes. These changes are different in glioblastomas and metastases, and mechanisms other than Wallerian degeneration may be contributing to the observed changes.

Utility of Hounsfield units in predicting fusion rates of patients undergoing anterior odontoid screw fixation following Anderson d'Alonzo type II and shallow type III fractures.

BACKGROUND: Main objective of this study was to determine whether Hounsfield units (HU) measured in three areas of the axis correlate with successful fusion in patients with type II and shallow type III C2 fractures undergoing anterior odontoid screw osteosynthesis (AOSF). METHODS: Forty-five patients with C2 fractures treated via AOSF were analyzed. Only bony fusion with bone trabeculations across the fracture line was considered a successful result. Preoperative HU values were measured in three zones- corpus, watershed and dens. Statistical analysis was performed to determine significant differences between HU of fused and unfused patients in all three zones of a complete and adjusted patient cohort. RESULTS: Statistically significant differences of HU values were found between fused (corpus- 363.7, watershed- 327.9) and unfused (corpus- 279.5, watershed- 194.2) of the complete cohort and the adjusted cohort. Cut-off HU values in the watershed zone were calculated for the complete (250 and 300) and adjusted cohort (240 and 260), dividing patients into three groups of bone quality. Patients with high watershed bone quality (HU>300) achieved successful fusion in 84.62%, patients with low bone quality (HU<250) in 3.85% and patients with medium bone quality (HU 250-300) in 50%. CONCLUSIONS: Preoperative measurement of HU can be used to predict the probability of successful fusion in patients undergoing AOSF for type II and shallow type III C2 fractures. AOSF is a highly effective treatment modality in patients with watershed HU>300, whereas alternatives should be considered in patients with watershed HU<250.

Anatomy of the supraventricular portion of the pyramidal tract.

BACKGROUND: The anatomy and somatotopy of the pyramidal tract during its course in the internal capsule has recently been discussed by many publications. However, the reports on the anatomy of the clinically more important supraventricular portion of the tract are scarce. The objective of this study is to investigate the anatomy and somatotopy of the supraventricular portion of the pyramidal tract. METHODS: In 13 patients undergoing surgery with subcortical electric stimulation for tumors located in the supraventricular white matter close to the pyramidal tract (as depicted by diffusion tensor tracking [DTT]), the relationship between the position of the stimulation point and the motor response in the arm or leg was analyzed. Additionally, the somatotopic organization of the tract was studied using separate tracking of arm and leg fibers in 20 healthy hemispheres. Finally, the course of the tract was studied by dissecting 15 previously frozen human hemispheres. RESULTS: In most cases, subcortical stimulation during the resection of tumors located behind and in front of the pyramidal tract elicited leg and arm movement, respectively. This association of stimulation point position with motor response type was significant. A DTT study of the somatotopy demonstrated a varying degree of rotation of the leg and arm fibers from mediolateral to posteroanterior configuration. Anatomic dissections demonstrated a folding-fan like structure of the pyramidal tract with a similar rotation pattern. CONCLUSION: The pyramidal tract undergoes a large part of its rotation from mediolateral to posteroanterior configuration during its course in the supraventricular white matter, although interindividual differences exist.

Intrathecal midazolam as supplementary analgesia for chronic lumbar pain--15 years' experience.

BACKGROUND: The antinociceptive effect of intrathecal midazolam is based on its affecting spinal gamma-amino butyric acid receptors. OBJECTIVE: To evaluate pain relief in patients with chronic low back pain and failed back surgery syndrome after a single-shot intrathecal administration of midazolam. DESIGN: A prospective, open-label study. OUTCOME MEASURES: The analgesic effect was determined using a patient questionnaire during subsequent visits to the pain therapy service. We classified at least a 50% pain reduction with improved quality of life and improved functional condition as a positive outcome. RESULTS: Between 1995 and 2010, we performed 500 administrations: 227 administrations in 57 male patients and 273 administrations in 69 female patients. We performed 81 administrations for chronic low back pain and 419 administrations for failed back surgery syndrome. The average age of our patients was 50 years (range 28 to 86). The dose administered ranged from 2 to 5 mg of midazolam. The analgesic effect lasted 9.7 weeks on average, ranging from 1 week to 3 years; the most common reported duration was between 4 and 12 weeks (3 months). In 65% of patients, we achieved pain relief lasting 4 weeks or longer; in 13%, the administration provided no analgesic effect at all. The incidence of side effects (drowsiness, nausea, headache, or transient worsening of complaints) was rather low. CONCLUSION: Intrathecal midazolam is a useful supplement to standard analgesic therapy with opioids, non-opioids, or spinal steroids.

Development of the Cerebrospinal Fluid in Early Stage after Hemorrhage in the Central Nervous System.

Extravasation of blood in the central nervous system (CNS) represents a very strong damaged associated molecular patterns (DAMP) which is followed by rapid inflammation and can participate in worse outcome of patients. We analyzed cerebrospinal fluid (CSF) from 139 patients after the CNS hemorrhage. We compared 109 survivors (Glasgow Outcome Score (GOS) 5-3) and 30 patients with poor outcomes (GOS 2-1). Statistical evaluations were performed using the Wilcoxon signed-rank test and the Mann-Whitney U test. Almost the same numbers of erythrocytes in both subgroups appeared in days 0-3 (p = 0.927) and a significant increase in patients with GOS 2-1 in days 7-10 after the hemorrhage (p = 0.004) revealed persistence of extravascular blood in the CNS as an adverse factor. We assess 43.3% of patients with GOS 2-1 and only 27.5% of patients with GOS 5-3 with low values of the coefficient of energy balance (KEB < 15.0) in days 0-3 after the hemorrhage as a trend to immediate intensive inflammation in the CNS of patients with poor outcomes. We consider significantly higher concentration of total protein of patients with GOS 2-1 in days 0-3 after hemorrhage (p = 0.008) as the evidence of immediate simultaneously manifested intensive inflammation, swelling of the brain and elevation of intracranial pressure.

Morphological and Hemodynamic Changes during Cerebral Aneurysm Growth.

Computational fluid dynamics (CFD) has grown as a tool to help understand the hemodynamic properties related to the rupture of cerebral aneurysms. Few of these studies deal specifically with aneurysm growth and most only use a single time instance within the aneurysm growth history. The present retrospective study investigated four patient-specific aneurysms, once at initial diagnosis and then at follow-up, to analyze hemodynamic and morphological changes. Aneurysm geometries were segmented via the medical image processing software Mimics. The geometries were meshed and a computational fluid dynamics (CFD) analysis was performed using ANSYS. Results showed that major geometry bulk growth occurred in areas of low wall shear stress (WSS). Wall shape remodeling near neck impingement regions occurred in areas with large gradients of WSS and oscillatory shear index. This study found that growth occurred in areas where low WSS was accompanied by high velocity gradients between the aneurysm wall and large swirling flow structures. A new finding was that all cases showed an increase in kinetic energy from the first time point to the second, and this change in kinetic energy seems correlated to the change in aneurysm volume.

Identification of the large descending tracts using diffusion tensor imaging in Chiari III malformation.

INTRODUCTION: The paper focuses on the use of diffusion tensor imaging (DTI) in the evaluation of one case of Chiari III malformation. CASE REPORT: In the case discussed, DTI was used to delineate the position of large descending tracts within the malformation and the reconstructed images were used to plan the surgical procedure. DISCUSSION: The clinical and imaging findings, the technical aspects of the DTI fiber tract reconstruction and the outcome are summarized.

Spontaneous Subarachnoid Hemorrhage in a Patient with a Co-Existent Posterior Communicating Artery Aneurysm and Cervical Spine Aneurysm Associated with Ventral Arterio-Venous Fistula.

: Severe spontaneous subarachnoid hemorrhage (SAH) is predominantly caused by aneurysm rupture, with non-aneurysmal vascular lesions representing only a minority of possible causes. We present the case of a 58-year old lady with a coincidental posterior communicating artery (PCom) aneurysm and a high cervical spine arterio-venous fistula associated with a small ruptured aneurysm. After the emergency clipping of the PCom aneurysm, additional diagnostic procedures-repeated digital subtraction angiography and spinal magnetic resonance imaging, revealed the actual cause of the SAH, a type-A ventral intradural fistula at cervical level C2/3. The fistula was treated micro surgically via a ventral approach using C3 somatectomy and C2-4 stabilization after the initial failure of endovascular therapy. Furthermore, the patient was treated for complications associated with severe SAH, including acute hydrocephalus and meningitis. In cases where the SAH pattern and perioperative findings do not suggest an intracranial aneurysm as the source of SAH, further diagnostic investigation is warranted to discover the real cause. Patients with severe non-aneurysmal SAH require a similar algorithm in diagnosing the cause of the hemorrhage as well as complex conditions such as ruptured aneurysms.