Embolization techniques of spontaneous direct carotid-cavernous fistulae: a single-center experience.

PURPOSE: Spontaneous direct carotid-cavernous fistula (CCF) are usually caused by a ruptured carotid cavernous aneurysm. We studied treatment of spontaneous direct CCFs in a single-center cohort of a high-volume tertiary referral center, reporting anatomical details, technical approaches of treatment, and outcomes. METHODS: Adult patients with a spontaneous direct CCF treated between 2010-2022 with follow-up MRI and/or DSA imaging available were retrospectively analyzed. We studied age, sex, clinical presentation, angiographic findings, treatment techniques, outcomes, and complications. RESULTS: Out of 80 patients with CCFs, twelve patients were treated for a non-traumatic direct CCF (15%) in 13 sessions. Median age was 65 years. Two patients had an underlying connective tissue disorder. In 10 cases, the direct CCF was caused by a ruptured cavernous carotid aneurysm. The direct CCFs were treated by endovascular transarterial embolization (10 cases), transvenous embolization (1 case), or surgery (1 case). Selective closure of the shunt was possible in 10 patients. Two patients were treated with parent vessel occlusion (PVO; one endovascular; one surgical, with bypass). Complications occurred in 2 / 12 patients (17%), with permanent morbidity in two patients (17%): trigeminal neuralgia after PVO and new infarct after surgical PVO and bypass. Selective closure of CCF resulted in no morbidity. There was no mortality in our series. CONCLUSION: Spontaneous direct CCFs are caused by rupture of a cavernous carotid aneurysm in most cases. Selective closure of the shunt, usually feasible transarterially with coils, achieves good results. Reconstructive endovascular techniques are preferred to minimize treatment related neurological complications.

Clinical uncertainty in large vessel occlusion ischemic stroke: does automated perfusion imaging make a difference? An intra-rater and inter-rater agreement study.

BACKGROUND: Limited research exists regarding the impact of neuroimaging on endovascular thrombectomy (EVT) decisions for late-window cases of large vessel occlusion (LVO) stroke. OBJECTIVE: T0 assess whether perfusion CT imaging: (1) alters the proportion of recommendations for EVT, and (2) enhances the reliability of EVT decision-making compared with non-contrast CT and CT angiography. METHODS: We conducted a survey using 30 patients drawn from an institutional database of 3144 acute stroke cases. These were presented to 29 Canadian physicians with and without perfusion imaging. We used non-overlapping 95% confidence intervals and difference in agreement classification as criteria to suggest a difference between the Gwet AC1 statistics (κG). RESULTS: The percentage of EVT recommendations differed by 1.1% with or without perfusion imaging. Individual decisions changed in 21.4% of cases (11.3% against EVT and 10.1% in favor). Inter-rater agreement (κG) among the 29 raters was similar between non-perfusion and perfusion CT neuroimaging (κG=0.487; 95% CI 0.327 to 0.647 and κG=0.552; 95% CI 0.430 to 0.675). The 95% CIs overlapped with moderate agreement in both. Intra-rater agreement exhibited overlapping 95% CIs for all 28 raters. κG was either substantial or excellent (0.81-1) for 71.4% (20/28) of raters in both groups. CONCLUSIONS: Despite the minimal difference in overall EVT recommendations with either neuroimaging protocol one in five decisions changed with perfusion imaging. Regarding agreement we found that the use of automated CT perfusion images does not significantly impact the reliability of EVT decisions for patients with late-window LVO.

Transarterial Embolization of Dural Arteriovenous Fistulas: Conventional, Pressure Cooker, and Microballoon Catheter Embolization Techniques.

BACKGROUND AND OBJECTIVES: Dural fistulas are abnormal connections between dural arteries and intracranial veins treated mainly endovascularly in most settings. The aim was to examine a single-institution experience of microballoon catheter transarterial embolization (TAE) of dural arteriovenous fistulas (dAVFs) and compare it with other TAE techniques. METHODS: We retrospectively identified all dAVFs treated at our institution between 2017 and 2022 with microballoon, conventional, and pressure cooker TAE. We studied occlusion and retreatment rates, treatment-related complications, and radiation doses. RESULTS: During the study period, 66 patients underwent 75 TAE procedures to treat 68 dAVFs: 47 conventional TAE, 14 pressure cooker TAE, and 14 microballoon TAE. Median age of the study population was 63 years with 32% females. The most common dAVF location was the transverse sinus and 20% of dAVFs presented with hemorrhage. At 3-month follow-up, stable complete occlusion of the dAVF was seen in 72% (n = 34) after conventional TAE, 79% (n = 11) after pressure cooker TAE, and 86% (n = 12) after microballoon TAE. Retreatment was required in 19% (n = 9) after conventional TAE, 7% (n = 1) after pressure cooker TAE, and 7% (n = 1) after microballoon TAE. Treatment-related complications occurred in 17% (n =) after conventional TAE, 29% (n = 4) after pressure cooker TAE, and 7% (n = 1) after microballoon TAE. CONCLUSION: In our experience, microballoon TAE of dAVFs resulted in better initial and 3-month angiographic outcomes and required less retreatment than conventional TAE. Microballoon TAE also resulted in fewer treatment-related complications than other techniques. In our experience, microballoon TAE is a reliable and safe endovascular technique to treat dAVFs.

Delayed Foreshortening and Prolapse of Silk Vista Baby into Superior Cerebellar Artery Aneurysm.

BACKGROUND: Flow diversion has evolved as a minimally invasive treatment for intracranial aneurysms. The Silk Vista Baby (SVB) can be navigated into small cerebral vessels because it can be deployed through a low-profile microcatheter. METHODS: We report on treating a patient in his 70s with an unruptured fusiform right superior cerebellar artery aneurysm using an SVB. RESULTS: Significant foreshortening of the device was noted during the initial procedure; however, the position was satisfactory with good apposition and clearance of the aneurysm neck. A stable position of the SVB on 1-day and 2-month postprocedural computed tomography angiography was also demonstrated. Subsequently, a 6-month follow-up computed tomography angiography detected delayed foreshortening and prolapse of the SVB into the aneurysm, for which an additional SVB was placed in a second procedure. There were no complications and the patient remained clinically well. CONCLUSIONS: Although the intraoperative foreshortening was not unexpected, the delayed postprocedural behavior of proximal foreshortening and subsequent prolapse of the SVB into the aneurysm have not been previously described. We would like to share this for awareness in this technical note.

Use of the neuroform atlas for stenting of intracranial atherosclerotic disease: Clinical and angiographic outcomes.

BACKGROUND: Intracranial atherosclerotic disease (ICAD) is a potential cause of ischemic stroke. Treatment of ICAD can include intracranial stenting. There are specifically designed stents for this use-case; however, less is known about the off-label use of the Neuroform Atlas stent. In this study, we describe the outcomes of the Neuroform Atlas stent for treatment of ICAD. METHODS: Adult patients with symptomatic ICAD failing best medical treatment undergoing elective intracranial stenting using the Neuroform Atlas stent between November 2018 and March 2021 were included. Patient demographics, procedure-related details and clinical and imaging outcomes were analyzed. RESULTS: Eighteen patients met the inclusion criteria, with a mean follow-up duration of 9.6 ± 6.8 (standard deviation) months. There were two procedure-related mortalities (one massive intracranial hemorrhage and one groin site complication with sepsis). Fifteen patients were alive at the 6-month follow-up, all with satisfactory stent patency on follow-up imaging without any new ischemic events. Modified Rankin Scale at latest follow-up was 1.9 (interquartile range 5). CONCLUSION: In this single-center consecutive series, intracranial stenting with the Neuroform Atlas stent was a safe and effective treatment for symptomatic ICAD patients failing best medical management.

Thoracolumbar spinal dural arteriovenous fistulae present with longer arteriovenous transit compared to cranial and cervical dural fistulae.

BACKGROUND: Thoraco-lumbar spinal dural arteriovenous fistulae represent a rare subset of central nervous system vascular malformations. One of the unique features of spinal dural arteriovenous fistulae is their extremely low propensity to cause hemorrhage (either parenchymal or subarachnoid), with a distinct clinical presentation of myelopathy secondary to spinal venous congestion. The exact mechanism for this unique presentation is still unclear. METHODS: Following institutional review board approval, we retrospectively analyzed our prospectively maintained database of spinal dural arteriovenous fistulae and cranial (cr) DAVF cases presenting between 2008 and 2021. For all cases, angiograms were reviewed and arteriovenous transit times were calculated. Patient demographics, angiographic features, and clinical and radiological outcomes were assessed. RESULTS: In total, 66 patients presenting with confirmed thoracolumbar spinal dural arteriovenous fistulaes were identified and compared to patients presenting with cervical spinal dural arteriovenous fistulaes (n = 10), ruptured crDAVFs (n = 32) and unruptured crDAVFs (n = 20). Mean age in the target group was 66 ± 13 versus 57-62 in the other groups, p < 0.05 on one-way analysis of variance; with 80% males versus 50%-65% in other groups. Mean arteriovenous transit time in the thoracolumbar group measured 1.98 s ± 0.96 versus 0.25-0.5 s range in other groups (p < 0.0001 on one-way analysis of variance). CONCLUSION: Prolonged arteriovenous transit times may represent a distinct feature of thoracolumbar spinal dural arteriovenous fistulaes. This may, amongst other factors, play a role in the observed lesser likelihood of hemorrhagic complications compared to other dural arteriovenous shunts.

Duplication of the internal maxillary artery: Anatomical and clinical considerations.

Duplication of the internal maxillary artery (IMAX) results from a failed regression of either the embryological superficial or deep ring and is reported to be exceedingly rare. We present a patient with this rare anatomical variant who was treated by endovascular technique in the clinical context of an acute oropharyngeal hemorrhage.

Embolization strategies for intracranial dural arteriovenous fistulas with an isolated sinus: a single-center experience in 20 patients.

BACKGROUND: Intracranial dural arteriovenous fistulas (DAVFs) draining into an isolated sinus segment constitute a specific entity within the spectrum of cranial dural AV shunts, with under-reporting of their optimal treatment. OBJECTIVE: To describe the multimodal treatment approach to isolated sinus DAVFs in a large single-center cohort. METHODS: Retrospective analysis of adult patients with an isolated sinus DAVF treated at our institution between 2004 and 2020 was performed. Cases were analyzed for demographics, clinical presentation, angiographic findings, treatment techniques, angiographic and clinical outcomes, and complications. RESULTS: Of 317 patients with DAVFs, 20 (6.3%) with an isolated sinus DAVF underwent treatment. Transarterial embolization was performed through the middle meningeal artery in 9 of 12 procedures, with a success rate of 66.7%. Transarterial glue embolization proved successful in two of five procedures (40%) and Onyx in six of seven procedures (85.7%). Transvenous embolization (TVE) with navigation via the occlusion into the isolated sinus was successful in seven out of nine procedures (77.8%). All three open TVE and one pure open surgical procedure gained complete closure of the fistula. There were two major complications. Complete occlusion of the fistula was eventually obtained in all cases (100%). CONCLUSIONS: Isolated sinus DAVFs are always aggressive and require a multimodal approach to guarantee closure of the shunt. Transarterial treatment with Onyx achieves good results. Transvenous treatment appears equally successful, navigating into the occluded segment across the occlusion or via burr hole as backup.

Case report: Candida krusei spondylitis in an immunocompromised patient.

BACKGROUND: Invasive infections with Candida krusei are uncommon and rarely complicated by spondylitis. Previous described cases were solely treated with antimycotic therapy, despite guidelines recommending surgical interventions. CASE PRESENTATION: We describe a case of C. krusei spondylitis in a patient treated with chemotherapy for acute myeloid leukemia. After induction chemotherapy, the patient developed a candidemia, which was treated with micafungin. One month after the candidemia, the patient was admitted with severe lumbar pain. Spondylitis of the L4 and L5 vertebra was diagnosed on MR-imaging, with signs suggesting an atypical infection. The patient was treated with anidulafungin combined with voriconazole. Despite maximal conservative management symptoms gradually worsened eventually requiring surgical intervention. CONCLUSIONS: In contrast to previous case reports, antimycotic treatment alone could be insufficient in treating C. krusei spondylitis.

Accurate MR Image Registration to Anatomical Reference Space for Diffuse Glioma.

To summarize the distribution of glioma location within a patient population, registration of individual MR images to anatomical reference space is required. In this study, we quantified the accuracy of MR image registration to anatomical reference space with linear and non-linear transformations using estimated tumor targets of glioblastoma and lower-grade glioma, and anatomical landmarks at pre- and post-operative time-points using six commonly used registration packages (FSL, SPM5, DARTEL, ANTs, Elastix, and NiftyReg). Routine clinical pre- and post-operative, post-contrast T1-weighted images of 20 patients with glioblastoma and 20 with lower-grade glioma were collected. The 2009a Montreal Neurological Institute brain template was used as anatomical reference space. Tumors were manually segmented in the patient space and corresponding healthy tissue was delineated as a target volume in the anatomical reference space. Accuracy of the tumor alignment was quantified using the Dice score and the Hausdorff distance. To measure the accuracy of general brain alignment, anatomical landmarks were placed in patient and in anatomical reference space, and the landmark distance after registration was quantified. Lower-grade gliomas were registered more accurately than glioblastoma. Registration accuracy for pre- and post-operative MR images did not differ. SPM5 and DARTEL registered tumors most accurate, and FSL least accurate. Non-linear transformations resulted in more accurate general brain alignment than linear transformations, but tumor alignment was similar between linear and non-linear transformation. We conclude that linear transformation suffices to summarize glioma locations in anatomical reference space.

Association between tumor location and neurocognitive functioning using tumor localization maps.

INTRODUCTION: Patients with diffuse glioma often experience neurocognitive impairment already prior to surgery. Pertinent information on whether damage to a specific brain region due to tumor activity results in neurocognitive impairment or not, is relevant in clinical decision-making, and at the same time renders unique information on brain lesion location and functioning relationships. To examine the impact of tumor location on preoperative neurocognitive functioning (NCF), we performed MRI based lesion-symptom mapping. METHODS: Seventy-two patients (mean age 40 years) with a radiologically suspected glioma were recruited preoperatively. For each of the six cognitive domains tested, we used tumor localization maps and voxel-based lesion-symptom mapping analyses to identify cortical and subcortical regions associated with NCF impairment. RESULTS: Compared to healthy controls, preoperative NCF was significantly impaired in all cognitive domains. Most frequently affected were attention (30% of patients) and working memory (20% of patients). Deficits in attention were significantly associated with regions in the left frontal and parietal cortex, including the precentral and parietal-opercular cortex, and in left-sided subcortical fiber tracts, including the arcuate fasciculus and corticospinal tract. Surprisingly, no regions could be related to working memory capacity. For the other neurocognitive domains, impairments were mainly associated with regions in the left hemisphere. CONCLUSIONS: Prior to treatment, patients with diffuse glioma in the left hemisphere run the highest risk to have NCF deficits. Identification of a left frontoparietal network involved in NCF not only may optimize surgical procedures but may also be integrated in counseling and cognitive rehabilitation for these patients.

Preoperative Resectability Estimates of Nonenhancing Glioma by Neurosurgeons and a Resection Probability Map.

BACKGROUND: Preoperative interpretation of resectability of diffuse nonenhancing glioma is primarily based on individual surgical expertise. OBJECTIVE: To compare the accuracy and precision between observed resections and preoperative estimates of neurosurgeons and a resection probability map (RPM). We hypothesize that the RPM estimates is as good as senior neurosurgeons. METHODS: A total of 234 consecutive patients were included from 2 centers, who had resective surgery with functional mapping between 2006 and 2012 for a supra-tentorial nonenhancing glioma. Extent of resection (EOR) and residual tumor volume (RTV) were segmented and an RPM was constructed in standard brain space. Three junior and three senior neurosurgeons estimated EOR and RTV, blinded for postoperative results. We determined the agreement between the estimates and calculated the diagnostic accuracy of the neurosurgeons and the RPM to predict the observed resections. RESULTS: Preoperative estimates of resection results by junior and senior neurosurgeons were significantly biased towards overestimation of EOR (4.2% and 11.2%) and underestimation of RTV (4.3 and 9.0 mL), whereas estimates of the RPM were unbiased (-2.6% and -.2 mL, respectively). The limits of agreement were wide for neurosurgeons and for the RPM. The RPM was significantly more accurate in identifying patients in whom an EOR >40% was observed than neurosurgeons. CONCLUSION: Neurosurgeons estimate preoperative resectability before surgery of a nonenhancing glioma rather accurate-with a small bias-and imprecise-with wide limits of agreement. An RPM provides unbiased resectability estimates, which can be useful for surgical decision-making, planning, and education.

Linking late cognitive outcome with glioma surgery location using resection cavity maps.

Patients with a diffuse glioma may experience cognitive decline or improvement upon resective surgery. To examine the impact of glioma location, cognitive alteration after glioma surgery was quantified and related to voxel-based resection probability maps. A total of 59 consecutive patients (range 18-67 years of age) who had resective surgery between 2006 and 2011 for a supratentorial nonenhancing diffuse glioma (grade I-III, WHO 2007) were included in this observational cohort study. Standardized neuropsychological examination and MRI were obtained before and after surgery. Intraoperative stimulation mapping guided resections towards neurological functions (language, sensorimotor function, and visual fields). Maps of resected regions were constructed in standard space. These resection cavity maps were compared between patients with and without new cognitive deficits (z-score difference >1.5 SD between baseline and one year after resection), using a voxel-wise randomization test and calculation of false discovery rates. Brain regions significantly associated with cognitive decline were classified in standard cortical and subcortical anatomy. Cognitive improvement in any domain occurred in 10 (17%) patients, cognitive decline in any domain in 25 (42%), and decline in more than one domain in 10 (17%). The most frequently affected subdomains were attention in 10 (17%) patients and information processing speed in 9 (15%). Resection regions associated with decline in more than one domain were predominantly located in the right hemisphere. For attention decline, no specific region could be identified. For decline in information speed, several regions were found, including the frontal pole and the corpus callosum. Cognitive decline after resective surgery of diffuse glioma is prevalent, in particular, in patients with a tumor located in the right hemisphere without cognitive function mapping.

Identifying the epileptogenic zone in interictal resting-state MEG source-space networks.

OBJECTIVE: In one third of patients, seizures remain after epilepsy surgery, meaning that improved preoperative evaluation methods are needed to identify the epileptogenic zone. A potential framework for such a method is network theory, as it can be applied to noninvasive recordings, even in the absence of epileptiform activity. Our aim was to identify the epileptogenic zone on the basis of hub status of local brain areas in interictal magnetoencephalography (MEG) networks. METHODS: Preoperative eyes-closed resting-state MEG recordings were retrospectively analyzed in 22 patients with refractory epilepsy, of whom 14 were seizure-free 1 year after surgery. Beamformer-based time series were reconstructed for 90 cortical and subcortical automated anatomic labeling (AAL) regions of interest (ROIs). Broadband functional connectivity was estimated using the phase lag index in artifact-free epochs without interictal epileptiform abnormalities. A minimum spanning tree was generated to represent the network, and the hub status of each ROI was calculated using betweenness centrality, which indicates the centrality of a node in a network. The correspondence of resection cavity to hub values was evaluated on four levels: resection cavity, lobar, hemisphere, and temporal versus extratemporal areas. RESULTS: Hubs were localized within the resection cavity in 8 of 14 seizure-free patients and in zero of 8 patients who were not seizure-free (57% sensitivity, 100% specificity, 73% accuracy). Hubs were localized in the lobe of resection in 9 of 14 seizure-free patients and in zero of 8 patients who were not seizure-free (64% sensitivity, 100% specificity, 77% accuracy). For the other two levels, the true negatives are unknown; hence, only sensitivity could be determined: hubs coincided with both the resection hemisphere and the resection location (temporal versus extratemporal) in 11 of 14 seizure-free patients (79% sensitivity). SIGNIFICANCE: Identifying hubs noninvasively before surgery is a valuable approach with the potential of indicating the epileptogenic zone in patients without interictal abnormalities.

Resection probability maps for quality assessment of glioma surgery without brain location bias.

BACKGROUND: Intraoperative brain stimulation mapping reduces permanent postoperative deficits and extends tumor removal in resective surgery for glioma patients. Successful functional mapping is assumed to depend on the surgical team's expertise. In this study, glioma resection results are quantified and compared using a novel approach, so-called resection probability maps (RPM), exemplified by a surgical team comparison, here with long and short experience in mapping. METHODS: Adult patients with glioma were included by two centers with two and fifteen years of mapping experience. Resective surgery was targeted at non-enhanced MRI extension and was limited by functional boundaries. Neurological outcome was compared. To compare resection results, we applied RPMs to quantify and compare the resection probability throughout the brain at 1 mm resolution. Considerations for spatial dependence and multiple comparisons were taken into account. RESULTS: The senior surgical team contributed 56, and the junior team 52 patients. The patient cohorts were comparable in age, preoperative tumor volume, lateralization, and lobe localization. Neurological outcome was similar between teams. The resection probability on the RPMs was very similar, with none (0%) of 703,967 voxels in left-sided tumors being differentially resected, and 124 (0.02%) of 644,153 voxels in right-sided tumors. CONCLUSION: RPMs provide a quantitative volumetric method to compare resection results, which we present as standard for quality assessment of resective glioma surgery because brain location bias is avoided. Stimulation mapping is a robust surgical technique, because the neurological outcome and functional-based resection results using stimulation mapping are independent of surgical experience, supporting wider implementation.

The desirability of education in didactic skills according to medical interns.

Since all doctors at some point in their career will be faced with their role as a teacher, it appears desirable that future doctors are educated in didactic skills. At present, however, there are no formal opportunities for developing didactic skills at the majority of Dutch medical faculties. The main question of this study is: How do medical interns perceive the quality and quantity of their education in didactic skills? The Dutch Association for Medical Interns (LOCA) ran a national survey among 1,008 medical interns that measured the interns' self-assessed needs for training in didactic skills during medical school. Almost 80 % of the respondents argue that the mastery of didactic skills composes an essential competency for doctors, with the skill of providing adequate feedback considered to be the most important didactic quality for doctors. Of the respondents, 41 % wish to be educated in didactic skills, both during their medical undergraduate degree and during their subsequent training to become a resident. Teaching while being observed and receiving feedback in this setting is regarded as a particularly valuable didactic method by 74 % of the medical interns. Of the respondents, 82 % would invest time to follow training for the development of didactic skills if it was offered. Medical interns stress the importance of doctors' didactic skills during their clinical internships. Compared with current levels, most interns desire increased attention to the formal development of didactic skills during medical school. Considering the importance of didactic skills and the need for more extensive training, the LOCA advises medical faculties to include more formal didactic training in the medical curriculum.

The effect of platelet-rich plasma in vitro on primary cells: rat osteoblast-like cells and human endothelial cells.

The aim of this study was to evaluate the effects of standardized platelet-rich plasma (PRP) concentrates from 10 human donors on cellular behavior. The standardized PRPs used were fivefold average and fivefold maximum baseline values in whole blood. Both these standardized PRPs were characterized by determining platelet numbers and subsequently growth factor concentrations in activated PRPs, called PRP derivatives. Platelet numbers in both types of standardized PRPs were significantly increased compared with whole blood. Further, both PRP derivatives contained significantly higher concentrations of platelet-derived growth factor-AA, platelet-derived growth factor-AB, and transforming growth factor-beta 1. Vascular endothelial growth factor concentrations were significantly elevated in only the most concentrated PRP derivative. Cell culture experiments with osteoblast-like cells showed that both PRP derivatives stimulated cell proliferation without inducing cell differentiation, whereas tube formation in endothelial cell cultures was significantly increased by adding low volume percentages of PRP derivative (2%–8%). Consequently, it can be concluded that there is no direct relationship between the number of platelets and the level of growth factors released from these platelets. PRP derivatives have the potency to stimulate angiogenesis dose dependently, while lacking the capacity to induce osteogenic differentiation. Yet, the proliferation of osteoblast-like cells can significantly be enhanced by supplementation of PRP derivatives.