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result(s) for
"Contreras Lopez, William Omar"
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Multi-centre analysis of networks and genes modulated by hypothalamic stimulation in patients with aggressive behaviours
by
Giacobbe, Peter
,
Hamani, Clement
,
Elias, Gavin JB
in
Aggression - psychology
,
Aggressive behavior
,
aggressive behaviour
2023
Deep brain stimulation targeting the posterior hypothalamus (pHyp-DBS) is being investigated as a treatment for refractory aggressive behavior, but its mechanisms of action remain elusive. We conducted an integrated imaging analysis of a large multi-centre dataset, incorporating volume of activated tissue modeling, probabilistic mapping, normative connectomics, and atlas-derived transcriptomics. Ninety-one percent of the patients responded positively to treatment, with a more striking improvement recorded in the pediatric population. Probabilistic mapping revealed an optimized surgical target within the posterior-inferior-lateral region of the posterior hypothalamic area. Normative connectomic analyses identified fiber tracts and functionally connected with brain areas associated with sensorimotor function, emotional regulation, and monoamine production. Functional connectivity between the target, periaqueductal gray and key limbic areas – together with patient age – were highly predictive of treatment outcome. Transcriptomic analysis showed that genes involved in mechanisms of aggressive behavior, neuronal communication, plasticity and neuroinflammation might underlie this functional network.
Journal Article
Intraoperative clinical application of augmented reality in neurosurgery: A systematic review
by
Navarro, Paula Alejandra
,
Contreras López, William Omar
,
Crispin, Santiago
in
Augmented Reality
,
Cameras
,
Head-mounted display
2019
•Augmented reality use in surgical fields is becoming more common.•Augmented reality is mostly used for tumors and aneurysms.•Augmented reality helps the neurosurgeon keep their eyes still on the site.•Augmented reality seems to improve safety and outcomes.
The interest and potential use of augmented reality (AR) in several medical fields since the early 90′s has increased consistently. It provides intraoperative guidance for surgical procedures by rendering visible what cannot be seen directly, possibly affecting surgical outcomes. Our objective was to conduct a systematic review of the intraoperative clinical application of augmented reality in neurosurgery, in studies published during the last five years. We carried out an electronic search in the PUBMED database using the terms “Augmented Reality” and “Neurosurgery.” After exclusions, 12 published articles that evaluated the utility of intraoperative clinical applications in surgical settings were included in our review. The results evaluated involved AR technique and visualization, time, complications, projection error, and located structures. We can conclude that the neurovascular application is the most frequent type of use for AR in neurosurgery (47.3%), followed by applications in neuro-oncological pathologies (46.7%), and non-vascular and non-neoplasic lesions (5.9%). The use of AR also allows a surgeon to maintain their view on the operative site permanently, and is useful for locating structures, guiding resections, and planning the craniotomy with more precision, decreasing the risk of injury. The intraoperative application of an augmented reality system helps to improve the quality and characteristics of the surgical field image. The injection of 3D images with AR allows for the successful integration of images in vascular, oncological and other lesions without the need of look away from the surgical field, improving safety, surgical experience, or clinical outcome. However, comparative studies are still required to determine its effectiveness.
Journal Article
Correlation of 18F-fluoroethyl tyrosine positron-emission tomography uptake values and histomorphological findings by stereotactic serial biopsy in newly diagnosed brain tumors using a refined software tool
by
Kirch, Robert
,
Albicker, Ulrich
,
Trippel, Michael
in
18F-FET PET-guided stereotactic biopsy
,
biopsy target
,
diagnostic and treatment management of cerebral gliomas
2015
Magnetic resonance imaging (MRI) is the standard neuroimaging method to diagnose neoplastic brain lesions, as well as to perform stereotactic biopsy surgical planning. MRI has the advantage of providing structural anatomical details with high sensitivity, though histological specificity is limited. Although combining MRI with other imaging modalities, such as positron-emission tomography (PET), has proven to increment specificity, exact correlation between PET threshold uptake ratios (URs) and histological diagnosis and grading has not yet been described.Objectives: The aim of this study was to correlate exactly the histopathological criteria of the biopsy site to its PET uptake value with high spatial resolution (mm3), and to analyze the diagnostic value of PET using the amino acid O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET) PET in patients with newly diagnosed brain lesions in comparison to histological findings obtained from stereotactic serial biopsy.Patients and methods: A total of 23 adult patients with newly diagnosed brain tumors on MRI were enrolled in this study. Subsequently to diagnoses, all patients underwent a 18F-FET PET-guided stereotactic biopsy, using an original newly developed software module, which is presented here. Conventional MRI, stereotactic computed tomography series, and 18F-FET PET images were semiautomatically fused, and hot-spot detection was performed for target planning. UR was determined using the uptake value from the biopsy sites in relation to the contralateral frontal white matter. UR values ≥1.6 were considered positive for glioma. High-grade glioma (HGG) was suspected with URs ≥3.0, while low-grade glioma (LGG) was suspected with URs between 1.6 and 3.0. Stereotactic serial biopsies along the trajectory at multiple sites were performed in millimeter steps, and the FET URs for each site were correlated exactly with a panel of 27 different histopathological markers. Comparisons between FET URs along the biopsy trajectories and the histological diagnoses were made with Pearson product-moment correlation coefficients. Analysis of variance was performed to test for significant differences in maximum UR between different tumor grades.Results: A total of 363 biopsy specimens were taken from 23 patients by stereotactic serial biopsies. Histological examination revealed eight patients (35%) with an LGG: one with a World Health Organization (WHO)-I lesion and seven with a WHO-II lesion. Thirteen (57%) patients revealed an HGG (two with a WHO-III and three with a WHO-IV tumor), and two patients (9%) showed a process that was neither HGG nor LGG (group X or no-grade group). The correlation matrix between histological findings and the UR revealed five strong correlations. Low cell density in tissue samples was found to have a significant negative correlation with the measured cortical uptake rate (r=-0.43, P=0.02), as well as moderate cell density (r=-0.48, P=0.02). Pathological patterns of proliferation (r=0.37, P=0.04), GFAP (r=0.37, P=0.04), and Olig2 (r=0.36, P=0.05) showed a significant positive correlation with cortical URs. Analysis of variance tests showed a significant difference between the LGG and the HGG groups (F=8.27, P<0.002), but no significant differences when differentiating between the X group and the HGG (P=0.2)/LGG (P=0.8) groups, nor between the no-grade group and the WHO-I group.Conclusion: 18F-FET PET is a valuable tool, as it allows the differentiation of HGGs from LGGs. Its use is not limited to preoperative evaluation; it may also refine biopsy targeting and improve tumor delimitation for radiotherapy. Histology is still necessary, and remains the gold standard for definitive diagnosis of brain lesions.
Journal Article
Personalized Medicine in Cancer Pain Management
by
Assefi, Marjan
,
Sharafshah, Alireza
,
López, William Omar Contreras
in
Analgesics
,
Analysis
,
Bioinformatics
2023
Background: Previous studies have documented pain as an important concern for quality of life (QoL) and one of the most challenging manifestations for cancer patients. Thus, cancer pain management (CPM) plays a key role in treating pain related to cancer. The aim of this systematic review was to investigate CPM, with an emphasis on personalized medicine, and introduce new pharmacogenomics-based procedures for detecting and treating cancer pain patients. Methods: This study systematically reviewed PubMed from 1990 to 2023 using keywords such as cancer, pain, and personalized medicine. A total of 597 publications were found, and after multiple filtering processes, 75 papers were included. In silico analyses were performed using the GeneCards, STRING-MODEL, miRTargetLink2, and PharmGKB databases. Results: The results reveal that recent reports have mainly focused on personalized medicine strategies for CPM, and pharmacogenomics-based data are rapidly being introduced. The literature review of the 75 highly relevant publications, combined with the bioinformatics results, identified a list of 57 evidence-based genes as the primary gene list for further personalized medicine approaches. The most frequently mentioned genes were CYP2D6, COMT, and OPRM1. Moreover, among the 127 variants identified through both the literature review and data mining in the PharmGKB database, 21 variants remain as potential candidates for whole-exome sequencing (WES) analysis. Interestingly, hsa-miR-34a-5p and hsa-miR-146a-5p were suggested as putative circulating biomarkers for cancer pain prognosis and diagnosis. Conclusions: In conclusion, this study highlights personalized medicine as the most promising strategy in CPM, utilizing pharmacogenomics-based approaches to alleviate cancer pain.
Journal Article
Frame-based stereotactic neurosurgery in children under the age of seven: Freiburg University's experience from 99 consecutive cases
by
Monaco, Bernardo A.
,
Cordeiro, Joacir G.
,
Trippel, Michael
in
Biopsy - methods
,
Brain Neoplasms - pathology
,
Brain Neoplasms - surgery
2015
•The use of stereotactic frame in young children remains controversial in the literature.•99 frame-based surgeries in patients younger than seven years-old were analyzed.•The overall complication rate related to frame fixation was 5%. No neurological deficit.•Frame-based stereotactic neurosurgery is a safe technique also in the youngest patients.•Experience in the adjustment of the frame in children is crucial to reducing complications.
Stereotactic frame-based procedures proved to be precise, safe and are of widespread use among adult patients. Regarding pediatric patients few data is available, therefore the use of the stereotactic frame remains controversial in this population. This motivated us to report our experience in stereotactic procedures in the youngest patients and review the literature concerning this subject.
All frame-based procedures performed in patients younger than seven years in the University of Freiburg during the last 10 years were retrospectively analyzed and discussed under the light of the current literature.
The studied population was composed of 72 patients under the age of seven (mean 3.4±2.1 years-old), in whom 99 stereotactic procedures were performed. Brain tumor was present in 60 patients, hydrocephalus in five, cystic lesions in three, intracranial abscess in three and epilepsy in one patient. Stereotactic surgery was performed in 36 cases for brachytherapy, in 29 for biopsy, in 20 cases for cyst puncture, in eight for stereotactically guided endoscopic ventriculostomy, in five for catheter placement and in one case for depth electrode insertion. The overall complication rate was 5%. There were three cases of pin penetration through the skull, one case of frame dislocation after extensive cyst drainage and two skull fractures. Neurologic deficit related to frame fixation was observed in none of the cases. In disagreement with other authors, no case of pin related infection, air embolism, hematoma or CSF leak was observed.
Frame-based stereotactic neurosurgery is a safe technique also in the youngest patients. Rather than the simple use of torque-limiting devices training and experience in the manual adjustment of the stereotactic frame in children have been proven to be crucial factors that contribute to reducing pin related complications.
Journal Article
Parallel improvement in anxiety and tics after DBS for medically intractable Tourette syndrome: A long-term follow-up
by
Cury, Rubens Gisbert
,
Teixeira, Manoel Jacobsen
,
Barbosa, Danilo Costa
in
Anxiety
,
Anxiety - complications
,
Anxiety - diagnosis
2016
•Tourette syndrome can lead to a significantly impairment in quality of life.•DBS showed good outcomes after long-term follow-up for refractory TS.•Thalamic DBS may improve neuropsychiatry symptoms in addition to motor tics.
Journal Article
Neurosurgical treatment for dystonia: Long-term outcome in a case series of 80 patients
2014
In this study, we assessed the outcomes of patients with dystonia who underwent surgery treatment following the same algorithm.
Eighty consecutive patients with dystonia were submitted to neurosurgical management by means of intrathecal pump implantation, pallidotomy or deep brain stimulation (GPi or VIM). These patients included 48 patients with primary dystonia and 32 patients with secondary dystonia. Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS) was used to access pre- and post-operative outcomes. Patients were followed from 12 to 114 months.
Mean improvement in BFMDRS score among patients with PrD was 87.54% and 42.21% for SeD. Hemidystonic patients in both groups (PrD, SeD) showed a mean improvement in BFMDRS of 71.05% with GPiDBS. Patients with SeD due to previous perinatal insults showed a mean improvement in BFMDRS of 41.9%, with better results in purely dyskinetic patients (mean improvement of 61.2%).
Use of the proposed algorithm facilitated surgical decision planning, which translated in improved diagnostic rates, earlier interventions, appropriate management plans, and outcomes for both groups (PrD, SeD). Therefore, neuroimaging findings had a positive prognostic significance in the response to treatment in patients with primary dystonia compared with patients with secondary dystonia or distortion of basal ganglia anatomy. However, further studies in this line are warranted.
Journal Article
Intrathecal Morphine Therapy in the Management of Status Dystonicus in Neurodegeneration Brain Iron Accumulation Type 1
by
Assumpçao de Mônaco, Bernardo
,
Talamoni Fonoff, Erich
,
Santana Neville, Iuri
in
Adolescent
,
Dystonic Disorders - drug therapy
,
Dystonic Disorders - etiology
2015
Neurodegeneration with brain iron accumulation type 1 (NBIA-1) is a rare disorder characterized by progressive extrapyramidal dysfunction and dementia. NBIA-1 encompasses typical iron brain accumulation, mostly in the globus pallidus with secondary dementia, spasticity, rigidity, dystonia, and choreoathetosis. Treatment remains mostly symptomatic and is challenging. We present the case of a 14-year-old boy diagnosed with NBIA-1, presenting intractable progressive generalized dystonia leading to unresponsive status dystonicus (SD). The patient received a SynchroMed II (model 8637) programmable system pump (Medtronic®, Inc.) implant with an Ascenda intrathecal catheter for intrathecal morphine therapy (IMT). The initial dose of morphine was 1.0 mg/day. Overall, we observed no complications with IMT treatment and important improvement of the patient's motor function with stabilization of his incapacitating dystonia and his quality of life. On the Global Dystonia Severity Rating Scale, he presented 52% improvement, 30% improvement on the Unified Dystonia Rating Scale, and 38% improvement on the Fahn-Marsden Rating Scale after 10 months, when the dose was 1.7 mg/day. IMT should be considered as a potential palliative treatment in the management of intractable dystonia and SD secondary to NBIA-1.
Journal Article
Heart of science
2011
Biochemist at the George Washington University in Washington, DC, he shared the 1998 Nobel Prize in Physiology or Medicine for the discovery that nitric oxide acts as a signalling molecule in the cardiovascular system, prompting blood vessels to relax. Murad was born in Whiting, Indiana in 1936. His American mother was only 17 years old when she eloped with his father, an Albanian immigrant. His parents ran a restaurant, where he and his two brothers worked. Murad used to memorize customers' orders and mentally tally their bills, which he believed trained his memory and maths skills.
Journal Article
Interstitial brachytherapy with iodine-125 seeds for low grade brain stem gliomas in adults: Diagnostic and therapeutic intervention in a one-step procedure
by
Doostkam, Soroush
,
Trippel, Michael
,
Reithmeier, Thomas
in
Adult
,
Astrocytoma - radiotherapy
,
Biopsy
2013
To report on iodine-125 (I125) interstitial irradiation in the treatment of low grade brain stem gliomas in adults.
Ten patients with well-circumscribed lesions of the brainstem and histological confirmation of low grade glioma treated with stereotactically implanted I-125 seed in our department between 1995 and 2012 were retrospectively analyzed.
In 9 patients the lesion was treated with one I-125 seed and in one patient, 2 spatial separated lesions were implanted, therefore a total of 11 I-125 seeds were implanted. The mean volume of the 11 lesions was 2.76ml (range: 0.5–7.2ml), mean activity of the seeds was 6.23mCi (range: 1.5–11.1mCi), mean duration of irradiation was 28.5 days (range: 21–41 days) and mean effective dose rate was 9.16cGy/h (range: 6.2–12cGy/h). The 30 days perioperative morbidity and mortality rate was 0%. Median follow up was 72.5 month (range 5–168 months). Six of ten patients were free of progression until last follow up.
In our experience at the University Clinic in Freiburg Germany, interstitial radiosurgery based on MRI is a safe and effective method to diagnose and treat low grade gliomas of the brain stem. Furthermore randomized studies are needed to confirm the therapeutic impact of this method in comparison to external beam radiation of brain stem gliomas.
Journal Article