Igor Lima Maldonado

Rescue, Combined, and Stand-Alone Thrombectomy in the Management of Large Vessel Occlusion Stroke Using the Solitaire Device: A Prospective 50-Patient Single-Center Study Timing, Safety, and Efficacy

Background and Purpose— Large vessel occlusion in ischemic stroke is associated with a high degree of morbidity. When intravenous thrombolysis fails, mechanical thrombectomy can provide an alternative and synergistic method for flow restoration. In this study we evaluate the safety and efficacy of our stroke management protocol (RECOST study). Methods— Fifty consecutive ischemic stroke patients with large vessel occlusion were included. After clinical and MRI imaging assessment, 3 treatment strategies were selected according to time of symptom onset and location of vessel occlusion: rescue therapy; combined therapy; and stand-alone thrombectomy (RECOST study). MRI ASPECT score <5 was the main exclusion criterion. Mechanical thrombectomy was performed exclusively with the Solitaire flow restoration device. Clinical outcome was assessed after treatment, on day 1, and at discharge. Results— Mean patient age was 67.6 years, mean NIHSS score was 14.7, and mean ASPECT score was 6 on presentation. Vessel occlusions were in the middle cerebral artery (40%), the internal carotid artery (28%), and the basilar artery (32%). Rescue treatment represented 24%, combined therapy represented 56%, and stand-alone thrombectomy represented 20%. Mean recanalization time from symptoms onset was 377 minutes, with overall recanalization rate TICI 3 of 84%. NIHSS score at discharge was 6.5, with 60% of patients demonstrating NIHSS score 0 to 1 or an improvement of >9 points. Symptomatic complication rate was 10%. At 3 months, 54% of patients had a modififed Rankin scale score of 0 to 2, with an overall mortality rate of 12%. Conclusions— The present integrated stroke management protocol (RECOST study) demonstrated rapid, safe, and effective recanalization. We postulate that the Solitaire device contributed to high recanalization and patient selection using MRI ASPECT score to low and complication rates, therefore avoiding futile and dangerous interventions.

Frontal terminations for the inferior fronto-occipital fascicle: anatomical dissection, DTI study and functional considerations on a multi-component bundle

The anatomy and functional role of the inferior fronto-occipital fascicle (IFOF) remain poorly known. We accurately analyze its course and the anatomical distribution of its frontal terminations. We propose a classification of the IFOF in different subcomponents. Ten hemispheres (5 left, 5 right) were dissected with Klingler’s technique. In addition to the IFOF dissection, we performed a 4-T diffusion tensor imaging study on a single healthy subject. We identified two layers of IFOF. The first one is superficial and antero-superiorly directed, terminating in the inferior frontal gyrus. The second is deeper and consists of three portions: posterior, middle and anterior. The posterior component terminates in the middle frontal gyrus (MFG) and dorso-lateral prefrontal cortex. The middle component terminates in the MFG and lateral orbito-frontal cortex. The anterior one is directed to the orbito-frontal cortex and frontal pole. In vivo tractography study confirmed these anatomical findings. We suggest that the distribution of IFOF fibers within the frontal lobe corresponds to a fine functional segmentation. IFOF can be considered as a “multi-function” bundle, with each anatomical subcomponent subserving different brain processing. The superficial layer and the posterior component of the deep layer, which connects the occipital extrastriate, temporo-basal and inferior frontal cortices, might subserve semantic processing. The middle component of the deep layer could play a role in a multimodal sensory–motor integration. Finally, the anterior component of the deep layer might be involved in emotional and behavioral aspects.

Does the left superior longitudinal fascicle subserve language semantics? A brain electrostimulation study

Recent diffusion tensor imaging (DTI) tractography studies indicate that the supramarginal gyrus (SMG) represents a relay between frontal and temporal language sites. Some authors postulate that pathways connecting SMG to the posterior temporal lobe, i.e., the posterior part of the superior longitudinal fascicle (SLF) subserve semantic aspects of language. However, DTI provides only anatomic but not functional data. Therefore, it is impossible to conclude. Interestingly, intra-operative electrical mapping of cortical and subcortical language structures during tumor surgery is recognized as a reliable technique in functional neuroanatomy research. We mapped the underlying white matter of the SMG, especially the SLF, in 11 patients who underwent awake surgery for a glioma involving the left inferior parietal lobule. Using direct electrostimulation, we investigated the exact role of the SLF in language. Our findings indicate that the white matter under the inferior parietal lobule is highly involved in the dorsal phonological system. First, the SMG, connected to the ventral premotor cortex by horizontal fibers of the SLF, subserves articulatory processing, as demonstrated by dysarthria elicited by stimulation. Second, long arcuate fibers, found deeper in the white matter, subserve phonological processing, as supported by phonemic paraphasia induced by electrostimulation. Third, the most important result is that no semantic disturbances were elicited by stimulating the SLF, including its posterior part. Furthermore, no semantic disorders occurred postoperatively. Subcortical brain mapping by direct electrical stimulation does not provide arguments for a possible role of the left SLF in language semantic processing.

Neuroform Stent−Assisted Coiling of Unruptured Intracranial Aneurysms: Short- and Midterm Results from a Single-Center Experience with 68 Patients

BACKGROUND AND PURPOSE: Intracranial stent placement assists in the coiling of wide-neck aneurysms and aids in reconstructing and protecting the parent artery. In this study, we analyze our experience in the use of the Neuroform system. MATERIALS AND METHODS: Records of patients treated with a Neuroform stent from June 2003 to September 2007 were retrieved from a data base for analysis of population characteristics, occurrence of complications, and acute and midterm angiographic results. RESULTS: Sixty-eight patients harboring 76 aneurysms located primarily in the anterior circulation were treated. There were 5 cases (6.6%) of clot formation after deployment (1 with a permanent neurologic deficit), 1 case of perioperative stent displacement with hemorrhage, and 5 cases (6.6%) of transient neurologic deficit due to thromboembolic events. The morbidity-mortality rate at discharge was 2.9%. One patient presented with a delayed in-stent thrombosis, and 3 others, with silent stenosis. Twenty-four aneurysms (31.6%) were completely occluded in the initial embolization. However, a marked increase in the occlusion rate was observed, with 44 of the 68 aneurysms (64.7%) examined at the 18-month follow-up and 26 of the 46 aneurysms (56.5%) examined in the 3-year follow-up presenting with complete occlusion. At the end of the study, a neck remnant was present in 6 aneurysms (13%) and a residual sac, in 7 (15.2%). Mean follow-up time was 25.7 months. CONCLUSIONS: The present series demonstrates the relative safety and feasibility of the Neuroform stent−assisted coiling technique, which seems to provide better results over coiling alone for wide-neck aneurysms. Angiographic results improve with time due to progressive thrombosis of the aneurysm.

Stent Retrievers in Acute Ischemic Stroke: Complications and Failures during the Perioperative Period

BACKGROUND AND PURPOSE: Stent retriever–assisted thrombectomy promotes high recanalization rates in acute ischemic stroke. Nevertheless, complications and failures occur in more than 10% of procedures; hence, there is a need for further investigation. MATERIALS AND METHODS: A total of 144 patients with ischemic stroke presenting with large-vessel occlusion were prospectively included. Patients were treated with stent retriever–assisted thrombectomy ± IV fibrinolysis. Baseline clinical and imaging characteristics were incorporated in univariate and multivariate analyses. Predictors of recanalization failure (TICI 0, 1, 2a), and of embolic and hemorrhagic complications were reported. The relationship between complication occurrence and periprocedural mortality rate was studied. RESULTS: Median age was 69.5 years, and median NIHSS score was 18 at presentation. Fifty patients (34.7%) received stand-alone thrombectomy, and 94 (65.3%) received combined therapy. The procedural failure rate was 13.9%. Embolic complications were recorded in 12.5% and symptomatic intracranial hemorrhage in 7.6%. The overall rate of failure, complications, and/or death was 39.6%. The perioperative mortality rate was 18.4% in the overall cohort but was higher in cases of failure (45%; P = .003), embolic complications (38.9%; P = .0176), symptomatic intracranial hemorrhages (45.5%; P = .0236), and intracranial stenosis (50%; P = .0176). Concomitant fibrinolytic therapy did not influence the rate of recanalization or embolic complication, or the intracranial hemorrhage rate. Age was the only significant predictive factor of intracranial hemorrhage (P = .043). CONCLUSIONS: The rate of perioperative mortality was significantly increased in cases of embolic and hemorrhagic complications, as well as in cases of failure and underlying intracranial stenoses. Adjunctive fibrinolytic therapy did not improve the recanalization rate or collateral embolic complication rate. The rate of symptomatic intracranial hemorrhage was not increased in cases of combined treatment.

Middle longitudinal fasciculus delineation within language pathways: A diffusion tensor imaging study in human

INTRODUCTION The existence in the human brain of the middle longitudinal fasciculus (MdLF), initially described in the macaque monkey, is supported by diffusion tensor imaging studies. In the present work, we aim (1) to confirm that this fascicle is found constantly in control subjects with the use of DTI techniques and (2) to delineate the MdLF from the other fiber bundles that constitute the language pathways. MATERIALS AND METHODS Tractography was realized in four right-handed healthy volunteers for the arcuate fascicle, uncinate fascicle, inferior fronto-occipital fascicle, inferior longitudinal fascicle and the middle longitudinal fascicle. The fiber tracts were characterized for their size, mean fractional anisotropy (FA), for their length, number of streamlines, and lateralization indices were calculated. RESULTS The MdLF is found constantly and it is clearly delineated from the other fascicles that constitute the language pathways, especially the ventral pathway. It runs within the superior temporal gyrus white matter from the temporal pole, then it extends caudally in the upper part of the sagittal stratum and the posterior part of the corona radiata, to reach the inferior parietal lobule (angular gyrus). We found a leftward asymmetry for all fiber tracts when considering the mean FA. DISCUSSION Using DTI methods, we confirm that the MdLF connects the angular gyrus and the superior temporal gyrus. On the basis of these findings, the role of the MdLF is discussed. CONCLUSION The middle longitudinal fasciculus, connects the angular gyrus and the superior temporal gyrus and its course can be systematically differenciated from those of other fascicles composing both ventral and dorsal routes (IFOF, IFL, AF and UF).

Intermittent general anesthesia with controlled ventilation for asleep-awake-asleep brain surgery: a prospective series of 140 gliomas in eloquent areas.

BACKGROUND Awake brain tumor surgery is a unique opportunity for mapping sensorimotor and cognitive functions, allowing the operator to optimize the resection while preserving the patients quality of life. During this type of procedure, active participation of the patient is necessary. OBJECTIVE To assess the efficacy and safety of a method of intermittent general anesthesia with controlled ventilation for performing invasive cerebral mapping. METHODS We report our prospective and observational single-center study with an asleep-awake-asleep protocol. Aspects of feasibility, airway management, timing of each phase, and occurrence of adverse events were detailed. RESULTS During a 35-month period, 140 patients underwent resection of a glioma in an eloquent area. During the asleep phases, controlled ventilation with a laryngeal mask was always efficient. Orotracheal intubation was performed for some patients for the second asleep period. The patients remained fully awake for a mean time of 98 minutes. Postural discomfort was reported in 17.8% of cases. There was 1 case of aspiration of gastric contents with a favorable outcome and no mortality. CONCLUSION Intermittent general anesthesia with controlled ventilation for this type of neurosurgical procedure remains an anesthesiological challenge. However, the results of this study suggest that it may be feasible, reproducible, and relatively safe in the context of a standardized protocol involving members of both anesthesiology and surgery teams. Such a technique has a great potential to improve the surgical results, from both oncological and functional perspectives.

Prognostic factors related to clinical outcome following thrombectomy in ischemic stroke (RECOST Study). 50 patients prospective study

BACKGROUND AND AIMS New thrombectomy devices allow successful and rapid recanalization in acute ischemic stroke. Nevertheless prognostics factors need to be systematically analyzed in the context of these new therapeutic strategies. The aim of this study was to analyze prognostic factors related to clinical outcome following Solitaire FR thrombectomy in ischemic stroke. METHODS Fifty consecutive ischemic stroke patients with large vessel occlusion were included. Three treatment strategies were applied; rescue therapy, combined therapy, and standalone thrombectomy. DWI ASPECT score<5 was the main exclusion criterion after initial MRI (T2, T2, TOF, FLAIR, DWI). Sexes, age, time to recanalization were prospectively collected. Clinical outcome was assessed post treatment, day one and discharge by means of a NIHSS. Three months mRS evaluation was performed by an independent neurologist. The probability of good outcome at 3 months was assessed by forward stepwise logistic regression using baseline NIHSS score, Glasgow score at entrance, hyperglycemia, dyslipidemia, blood-brain barrier disruption on post-operative CT, embolic and hemorrhagic post procedural complication, ischemic brain lesion extension on 24h imaging, NIHSS at discharge, ASPECT score, and time to recanalization. All variables significantly associated with the outcome in the univariate analysis were entered in the model. The significance of adding or removing a variable from the logistic model was determined by the maximum likelihood ratio test. Odds-ratio (OR) and their 95% confidence intervals were calculated. RESULTS At 3 months 54% of patients had a mRS 0-2, 70% in MCA, 44% in ICA, and 43% in BA with an overall mortality rate of 12%. Baseline NIHSS score (p=0.001), abnormal Glasgow score at entrance (p=0.053) hyperglycemia (p=0.023), dyslipidemia (p=0.031), blood-brain barrier disruption (p=0.022), embolic and hemorrhagic post procedural complication, ischemic brain lesion extension on 24h imaging (p=0.008), NIHSS at discharge (0.001) were all factors significantly associated with 3 month clinical outcome. ASPECT subgroup (5-7 and 8-10), and time to recanalization were not correlated to 3 months outcome. Baseline NIHSS score (OR, 1.228; 95% CI, 1.075-1.402; p=0.002), hyperglycemia (OR, 10.013; 95% CI, 1.068-93.915; p=0.04), emerged as independent predictors of outcome at 3 months. Overall embolic complication rate was 10%, and symptomatic intracranial hemorrhage was 2%. CONCLUSION The MCA location was associated with the best clinical outcome. A DWI ASPECT cutoff score of 5 was reliable and safe. No correlation with time to recanalization was observed in this study. NIHSS and hyperglycemia at admission were the two factors independently associated with a bad outcome at 90 days.

Magnetic resonance-based deep brain stimulation technique: a series of 478 consecutive implanted electrodes with no perioperative intracerebral hemorrhage.

OBJECTIVE The aim of this study was to determine the safety of a deep brain stimulation technique consisting of a combination of routine general anesthesia, magnetic resonance imaging direct targeting, and a single penetration technique in a large population of patients undergoing operation for movement disorders. METHODS One hundred ninety-four patients treated with deep brain stimulation between 1996 and 2007 were assessed via a computerized database for intra- and perioperative events. Most patients were young; only 62 of them were older than 40 years (mean age, 31.1 years). General anesthesia was induced in all cases before placement of a magnetic resonance imaging-compatible stereotactic frame. Electrode implantation was done under radioscopic control via a rigid immobile cannula using a single cerebral perforation. No perioperative microelectrode recording or neurostimulation testing was used. Systematic postoperative magnetic resonance imaging was performed before frame removal. RESULTS A total of 478 electrodes were implanted in 220 procedures: 426 for dystonic-dyskinetic syndromes and 52 for Parkinson disease. The mean number of parenchymal penetrations per patient was 2.5 for the dystonic-dyskinetic syndrome group and 2.08 for the Parkinson disease group. Postimplantation magnetic resonance imaging detected no perioperative intraparenchymal hemorrhages. CONCLUSION We consider that the risk of hemorrhagic complication is multifactorial but closely related to the chosen technique.

Evidence of a middle longitudinal fasciculus in the human brain from fiber dissection

A rostrocaudal pathway connecting the temporal and parietal lobes was described in monkeys using autoradiography and was named the middle longitudinal fasciculus (MdLF). Recently, the use of diffusion tensor tractography has allowed it to be depicted in human volunteers. In the present study, a technique of fiber dissection was used in 18 cadaveric human brains to investigate the presence of this fasciculus and to detail its anatomical relationships. On the basis of our findings, fiber dissection provides evidence for a long horizontal bundle medial to the arcuate fasciculus and extending to the superior temporal gyrus. Its fibers occupy the lateral‐most layer of the upper portion of the stratum sagittale and partially cover the inferior fronto‐occipital fasciculus, which is situated deeper and slightly inferiorly. Whereas MdLF fibers continue on a relatively superficial level to reach the superior temporal gyrus, the inferior fronto‐occipital fasciculus penetrates the deep temporal white matter and crosses the insular lobe. Although diffusion tensor imaging suggests that the MdLF terminates in the angular gyrus, this was not confirmed by the present study. These long association fibers continue onward posteriorly into upper portions of the occipital lobe. Further studies are needed to understand the role of the MdLF in brain function.