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Featured researches published by Leodante da Costa.


International Journal of Radiation Oncology Biology Physics | 2012

Vertebral Compression Fracture (VCF) After Spine Stereotactic Body Radiation Therapy (SBRT): Analysis of Predictive Factors

Marcelo Cunha; Ameen Al-Omair; Eshetu G. Atenafu; Giuseppina Laura Masucci; D. Letourneau; Renee Korol; E. Yu; Peter Howard; F. Lochray; Leodante da Costa; Michael G. Fehlings; Arjun Sahgal

PURPOSE Vertebral compression fractures (VCFs) are increasingly observed after spine stereotactic body radiation therapy (SBRT). The aim of this study was to determine the risk of VCF after spine SBRT and identify clinical and dosimetric factors predictive for VCF. The analysis incorporated the recently described Spinal Instability Neoplastic Score (SINS) criteria. METHODS AND MATERIALS The primary endpoint of this study was the development of a de novo VCF (ie, new endplate fracture or collapse deformity) or fracture progression based on an existing fracture at the site of treatment after SBRT. We retrospectively scored 167 spinal segments in 90 patients treated with spine SBRT according to each of the 6 SINS criteria. We also evaluated the presence of paraspinal extension, prior radiation, various dosimetric parameters including dose per fraction (≥20 Gy vs <20 Gy), age, and histology. RESULTS The median follow-up was 7.4 months. We identified 19 fractures (11%): 12 de novo fractures (63%) and 7 cases of fracture progression (37%). The mean time to fracture after SBRT was 3.3 months (range, 0.5-21.6 months). The 1-year fracture-free probability was 87.3%. Multivariate analysis confirmed that alignment (P=.0003), lytic lesions (P=.007), lung (P=.03) and hepatocellular (P<.0001) primary histologies, and dose per fraction of 20 Gy or greater (P=.004) were significant predictors of VCF. CONCLUSIONS The presence of kyphotic/scoliotic deformity and the presence of lytic tumor were the only predictive factors of VCF based on the original 6 SINS criteria. We also report that patients with lung and hepatocellular tumors and treatment with SBRT of 20 Gy or greater in a single fraction are at a higher risk of VCF.


Neurosurgical Focus | 2009

Overview of the current role of endovascular and surgical treatment in spinal dural arteriovenous fistulas

Amir R. Dehdashti; Leodante da Costa; Karel G. terBrugge; Robert A. Willinsky; Michael Tymianski; M. Christopher Wallace

Dural arteriovenous fistulas are the most common vascular malformations of the spinal cord. These benign vascular lesions are considered straightforward targets of surgical treatment and possibly endovascular embolization, but the outcome in these cases depends mainly on the extent of clinical dysfunction at the time of the diagnosis. A timely diagnosis is an equally important factor, with early treatment regardless of the type more likely to yield significant improvements in neurological functioning. The outcomes after surgical and endovascular treatment are similar if complete obliteration of the fistulous site is obtained. In the present study, the authors evaluated the current role of each modality in the management of these interesting lesions.


Critical Care Medicine | 2013

Physical rehabilitation of the critically ill trauma patient in the ICU.

Paul T. Engels; Andrew Beckett; Gordon D. Rubenfeld; Hans J. Kreder; Joel A. Finkelstein; Leodante da Costa; Giuseppe Papia; Sandro Rizoli; Homer C. Tien

Objectives:To 1) review the existing evidence for early mobilization of the critically ill patients in the ICU with polytrauma; 2) provide intensivists with an introduction to the biomechanics, physiology, and nomenclature of injuries; 3) summarize the evidence for early mobilization in each anatomic area; and 4) provide recommendations for the mobilization of these patients. Data Sources:A literature search of the MEDLINE and EMBASE databases for articles published in English between 1980 and 2011. Study Selection:Studies pertaining to physical therapy and rehabilitation in trauma patients were selected. Articles were excluded if they dealt with pediatrics, geriatrics, burn injuries, isolated hand injuries, chronic (i.e., not acute) injuries, nontraumatic conditions, and pressure/decubitus ulcers, were in a language other than English, were published only in abstract form, were letters to the editor, were case reports, or were published prior to 1980. Data Extraction:Reviewers extracted data and summarized results according to anatomical areas. Data Synthesis:Of 1,411 titles and abstracts, 103 met inclusion criteria. We found no articles specifically addressing the rehabilitation of polytrauma patients in the ICU setting or patients with polytrauma in general. We summarized the articles addressing the role of mobilization for specific injuries and treatments. We used this evidence, in combination with biologic rationale and physician and surgeon experience and expertise, to summarize the important considerations when providing physical therapy to these patients in the ICU setting. Conclusions:There is a paucity of evidence addressing the role of early mobilization of ICU patients with polytrauma and patients with polytrauma in general. Evidence for the beneficial role of early mobilization of specific injuries exists. Important considerations when applying a strategy of early physical therapy and mobilization to this distinctive patient group are summarized.


Journal of Neurology, Neurosurgery, and Psychiatry | 2015

Delayed and disorganised brain activation detected with magnetoencephalography after mild traumatic brain injury

Leodante da Costa; Amanda Robertson; Allison Bethune; Matt J. MacDonald; Pang N. Shek; Margot J. Taylor; Elizabeth W. Pang

Background Awareness to neurocognitive issues after mild traumatic brain injury (mTBI) is increasing, but currently no imaging markers are available for mTBI. Advanced structural imaging recently showed microstructural tissue changes and axonal injury, mild but likely sufficient to lead to functional deficits. Magnetoencephalography (MEG) has high temporal and spatial resolution, combining structural and electrophysiological information, and can be used to examine brain activation patterns of regions involved with specific tasks. Methods 16 adults with mTBI and 16 matched controls were submitted to neuropsychological testing (Wechsler Abbreviated Scale of Intelligence (WASI); Conners; Alcohol Use Disorders Identification Test (AUDIT); Generalised Anxiety Disorder Seven-item Scale (GAD-7); Patient Health Questionnaire (PHQ-9); Symptom Checklist and Symptom Severity Score (SCAT2)) and MEG while tested for mental flexibility (Intra-Extra Dimensional set-shifting tasks). Three-dimensional maps were generated using synthetic aperture magnetometry beamforming analyses to identify differences in regional activation and activation times. Reaction times and accuracy between groups were compared using 2×2 mixed analysis of variance. Findings While accuracy was similar, patients with mTBI reaction time was delayed and sequence of activation of brain regions disorganised, with involvement of extra regions such as the occipital lobes, not used by controls. Examination of activation time showed significant delays in the right insula and left posterior parietal cortex in patients with mTBI. Conclusions Patients with mTBI showed significant delays in the activation of important areas involved in executive function. Also, more regions of the brain are involved in an apparent compensatory effort. Our study suggests that MEG can detect subtle neural changes associated with cognitive dysfunction and thus, may eventually be useful for capturing and tracking the onset and course of cognitive symptoms associated with mTBI.


Frontiers in Neurology | 2016

Temporal Profile of Cerebrovascular Reactivity Impairment, Gray Matter Volumes, and Persistent Symptoms after Mild Traumatic Head Injury

Leodante da Costa; Christiaan Hendrik Bas van Niftrik; David E. Crane; Jorn Fierstra; Allison Bethune

Objective Increased awareness around neurocognitive deficits after mild traumatic brain injury (mTBI) has progressed the search for objective, diagnostic, and monitoring tools, yet imaging biomarkers for mTBI and recovery are not established in clinical use. It has been suggested that mTBI impairs cerebrovascular reactivity (CVR) to CO2, which could be related to post-concussive syndrome (PCS). We investigate CVR evolution after mTBI using blood-oxygen-level dependent (BOLD) magnetic resonance imaging (MRI) and possible correlation with PCS. Methods A prospective cohort of 25 mTBI patients and 18 matched controls underwent BOLD MRI CVR measurements. A subset of 19 mTBI patients underwent follow-up testing. Visits took place at a mean of 63 and 180 days after injury. Symptoms were assessed with the Sport Concussion Assessment Tool 2 (SCAT2). Symptoms, CVR and brain volume [gray matter (GM), white matter (WM), and whole brain (WB)], age, and sex, were examined between groups and longitudinally within traumatic brain injury (TBI) patients. Results Traumatic brain injury participants were 72% males, mean age being 42.7 years. Control participants were 61% with mean age of 38.7 years. SCAT2 scores tended to improve among those mTBI patients with follow-up visits (p = 0.07); however, they did not tend to recover to scores of the healthy controls. Brain volumes were not statistically different between groups at the first visit (WM p = 0.71; GM p = 0.36). In mTBI patients, there was a reduction in GM volume between visits 1 and 2 (p = 0.0046). Although mean CVR indexes were similar (WM p = 0.27; GM p = 0.36; and WB p = 0.35), the correlation between SCAT2 and CVR was negative in controls (WM-r = −0.59; p = 0.010; GM-r = −0.56; p = 0.016; brain-r = −0.58; p = 0.012) and weaker and positive in mTBI (brain-r = 0.4; p = 0.046; GM-r = 0.4; p = 0.048). SCAT2 correlated with GM volume (r = 0.5215, p = 0.0075) in mTBI but not in controls (r = 0.2945, p = 0.2355). Conclusion There is a correlation between lower GM CVR indexes and lower performance on SCAT2 in patients with mTBI, which seems to be associated with more symptoms. This correlation seems to persist well beyond 120 days. mTBI may lead to a decrease in GM volume in these patients.


Annals of clinical and translational neurology | 2016

Reduced brain connectivity and mental flexibility in mild traumatic brain injury

Elizabeth W. Pang; Benjamin T. Dunkley; Sam M. Doesburg; Leodante da Costa; Margot J. Taylor

A mild traumatic brain injury (mTBI), or concussion, has known neuropsychological sequelae, and neuroimaging shows disturbed brain connectivity during the resting state. We hypothesized that task‐based functional connectivity measures, using magnetoencephalography (MEG), would better link the neurobiological underpinnings of cognitive deficits to specific brain damage.


Skull Base Surgery | 2007

Pituitary adenoma associated with intraventricular meningioma: case report.

Leodante da Costa; Jay Riva-Cambrin; Asheesh Tandon; Michael Tymianski

Although rare, the association of intracranial meningiomas and pituitary adenomas has been reported. Intraventricular meningiomas are unusual, and meningiomas located in the fourth ventricle are even more so. We report a patient who harbored a prolactin-secreting pituitary adenoma and a fourth ventricle meningioma who was treated with surgical resection of the latter and medical treatment for the former. To our knowledge, this is the first report of such an unusual association.


Arquivos De Neuro-psiquiatria | 2003

Cauda equina hemangioblastoma: case report

Leodante da Costa; Agustinho de Andrade; Bruno Perocco Braga; Carlos Alberto Ribeiro

Hemangioblastomas of the spinal cord are rare lesions, and those located at the cauda equina are even rarer. Most commonly these tumors are present in patients with von Hippel-Lindau (VHL) syndrome. We describe here the case of a 48 years old woman with a pure radicular hemangioblastoma, not associated with VHL, presenting with radicular pain, diagnosed with magnetic ressonance imaging (MRI) and submitted to total resection with a very good outcome. To our knownledge, this is the second report to describe the MRI aspect of histologically proved hemangioblastoma of the cauda equina in a patient without clinical criteria for VHL.


Journal of Magnetic Resonance Imaging | 2014

BOLD MRI and early impairment of cerebrovascular reserve after aneurysmal subarachnoid hemorrhage

Leodante da Costa; Jorn Fierstra; Joseph Fisher; David J. Mikulis; Jay S. Han; Michael Tymianski

Currently no biological or radiological marker is available to identify patients at risk of delayed ischemic deficit (DIND) after aneurysmal subarachnoid hemorrhage (aSAH). We hypothesized whether MR‐based quantitative assessment of cerebrovascular reserve (CVR) would detect early radiological markers of vasospasm and DIND. This manuscript describes our initial experience with this population. Five patients with aSAH underwent blood‐oxygen level dependent‐MRI (BOLD‐MRI) with CO2 challenge for assessment of whole brain CVR. Patients were examined as soon as possible after aneurysm treatment. We obtained good quality anatomical and functional images without complications. Initial anatomical cerebrovascular imaging showed no vasospasm in all patients. Two patients had abnormal CVR‐MRI tests and both developed DIND. Of the 3 others with normal CVR‐MRI, one developed posterior circulation DIND. One patient with a normal CVR‐MRI developed angiographic vasospasm but no DIND. Changes in CVR maps as early as 36 h after hemorrhage had good spatial correlation with delayed ischemia during short‐term follow‐up. Our series shows that MRI with CO2 challenge is feasible in this difficult population. Further developments might allow BOLD‐MRI with CO2 challenge to identify patients at risk and provide anatomical correlation with future DIND, opening a new venue for prophylactic treatments. Further study is warranted in a larger patient cohort. J. Magn. Reson. Imaging 2014;40:972–979.


Journal of NeuroInterventional Surgery | 2013

A multicenter registry of hydrocephalus following coil embolization of unruptured aneurysms: which patients are at risk and why it occurs

Raymond D Turner; Leodante da Costa; Karel G. terBrugge

Introduction Unexplained post-procedural events such as cerebral edema, inflammation, aseptic meningitis and hydrocephalus have been reported following unruptured cerebral aneurysm coiling. However, understanding of the etiology for these occurrences is limited due to their rare occurrence. A multicenter registry was developed to investigate further the occurrence of these events. Method This registry consisted of a retrospective analysis of unruptured aneurysms treated with hydrocoil that evolved to develop focal cerebral edema, inflammation, aseptic meningitis, or ventricular enlargement/hydrocephalus following uncomplicated coil embolization. Data points included pre, intra, and postoperative imaging, patient demographics, aneurysm demographics, procedural details such as coils used, medications administered, and intraprocedural complications, and all post-procedure follow-up including clinical status of the patients and all adverse events. Results Twenty-five patients (26 aneurysm coiling procedures) were found at 12 centers over an 8-year period. The mean aneurysm size was 13.7 mm. The average time from treatment to onset of symptoms was 8.5 months (2 weeks to 30 months, median 6 months). Delayed hydrocephalus was the most common clinical presentation. Six of the 25 patients were asymptomatic and did not require treatment. Conclusion Patients undergoing endovascular coiling may be at risk of developing delayed complications, which may or may not be symptomatic. This risk appeared low and was restricted mostly to larger aneurysms. These events can be difficult to detect due to delayed presentation.

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Elizabeth W. Pang

Hospital for Sick Children

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Victor X. D. Yang

Sunnybrook Health Sciences Centre

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Margot J. Taylor

Hospital for Sick Children

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Allison Bethune

Sunnybrook Health Sciences Centre

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Peter Howard

Sunnybrook Health Sciences Centre

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Arjun Sahgal

Sunnybrook Health Sciences Centre

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