Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Bert B. Vargas is active.

Publication


Featured researches published by Bert B. Vargas.


Stroke | 2012

Smartphone Teleradiology Application Is Successfully Incorporated Into a Telestroke Network Environment

Bart M. Demaerschalk; Jason E. Vargas; Dwight D. Channer; Brie N. Noble; Terri Ellen J Kiernan; Elizabeth A. Gleason; Bert B. Vargas; Timothy J. Ingall; Maria I. Aguilar; David W. Dodick; Bentley J. Bobrow

Background and Purpose— ResolutionMD mobile application runs on a Smartphone and affords vascular neurologists access to radiological images of patients with stroke from remote sites in the context of a telemedicine evaluation. Although reliability studies using this technology have been conducted in a controlled environment, this study is the first to incorporate it into a real-world hub and spoke telestroke network. The study objective was to assess the level of agreement of brain CT scan interpretation in a telestroke network between hub vascular neurologists using ResolutionMD, spoke radiologists using a Picture Archiving and Communications System, and independent adjudicators. Methods— Fifty-three patients with stroke at the spoke hospital consented to receive a telemedicine consultation and participate in a registry. Each CT was evaluated by a hub vascular neurologist, a spoke radiologist, and by blinded telestroke adjudicators, and agreement over clinically important radiological features was calculated. Results— Agreement (&kgr; and 95% CI) between hub vascular neurologists using ResolutionMD and (1) the spoke radiologist; and (2) independent adjudicators, respectively, were: identification of intracranial hemorrhage 1.0 (0.92–1.0), 1.0 (0.93–1.0), neoplasm 1.0 (0.92–1.0), 1.0 (0.93–1.0), any radiological contraindication to thrombolysis 1.0 (0.92–1.0), 0.85 (0.65–1.0), early ischemic changes 0.62 (0.28–0.96), 0.58 (0.30–0.86), and hyperdense artery sign 0.40 (0.01–0.80), 0.44 (0.06–0.81). Conclusions— CT head interpretations of telestroke network patients by vascular neurologists using ResolutionMD on Smartphones were in excellent agreement with interpretations by spoke radiologists using a Picture Archiving and Communications System and those of independent telestroke adjudicators using a desktop viewer. Clinical Trial Registration Information— www.clinicaltrials.gov unique identifier NCT00829361.


Stroke | 2012

Reliability of Real-Time Video Smartphone for Assessing National Institutes of Health Stroke Scale Scores in Acute Stroke Patients

Bart M. Demaerschalk; Sravanthi Vegunta; Bert B. Vargas; Qing Wu; Dwight D. Channer; Joseph G. Hentz

Background and Purpose— Telestroke reduces acute stroke care disparities between urban stroke centers and rural hospitals. Current technologies used to conduct remote patient assessments have high start-up costs, yet they cannot consistently establish quality timely connections. Smartphones can be used for high-quality video teleconferencing. They are inexpensive and ubiquitous among health care providers. We aimed to study the reliability of high-quality video teleconferencing using smartphones for conducting the National Institutes of Health Stroke Scale (NIHSS). Methods— Two vascular neurologists assessed 100 stroke patients with the NIHSS. The remote vascular neurologists assessed subjects using smartphone videoconferencing with the assistance of a bedside medical aide. The bedside vascular neurologists scored patients contemporaneously. Each vascular neurologists was blinded to the other’s NIHSS scores. We tested the inter-method agreement and physician satisfaction with the device. Results— We demonstrated high total NIHSS score correlation between the methods (r=0.949; P<0.001). The mean total NIHSS scores for bedside and remote assessments were 7.93±8.10 and 7.28±7.85, with ranges, of 0 to 35 and 0 to 37, respectively. Eight categories had high agreement: level of consciousness (questions), level of consciousness (commands), visual fields, motor left and right (arm and leg), and best language. Six categories had moderate agreement: level of consciousness (consciousness), best gaze, facial palsy, sensory, dysarthria, and extinction/inattention. Ataxia had poor agreement. There was high physician satisfaction with the smartphone. Conclusions— Smartphone high-quality video teleconferencing is reliable, easy to use, affordable for telestroke NIHSS administration, and has high physician satisfaction.


Cephalalgia | 2015

Occipital nerve block for the short-term preventive treatment of migraine: A randomized, double-blinded, placebo-controlled study:

Esma Dilli; Rashmi Halker; Bert B. Vargas; Joseph G. Hentz; Teresa Radam; Robert Rogers; David W. Dodick

Background Occipital nerve (ON) injections with corticosteroids and/or local anesthetics have been employed for the acute and preventive treatment of migraine for decades. However, to date there is no randomized, placebo-controlled evidence to support the use of occipital nerve block (ONB) for the prevention of migraine. Objective The objective of this article is to determine the efficacy of ONB with local anesthetic and corticosteroid for the preventive treatment of migraine. Participants and methods Patients between 18 and 75 years old with ICHD-II-defined episodic (> 1 attack per week) or chronic migraine (modified ICHD-II as patients with > 10 days with consumption of acute medications were permitted into the study) were randomized to receive either 2.5 ml 0.5% bupivacaine plus 0.5 ml (20 mg) methylprednisolone over the ipsilateral (unilateral headache) or bilateral (bilateral headache) ON or 2.75 ml normal saline plus 0.25 ml 1% lidocaine without epinephrine (placebo). Patients completed a one-month headache diary prior to and after the double-blind injection. The primary outcome measure was defined as a 50% or greater reduction in the frequency of days with moderate or severe migraine headache in the four-week post-injection compared to the four-week pre-injection baseline period. Results Thirty-four patients received active and 35 patients received placebo treatment. Because of missing data, the full analysis of 33 patients in the active and 30 patients in the placebo group was analyzed for efficacy. In the active and placebo groups respectively, the mean frequency of at least moderate (mean 9.8 versus 9.5) and severe (3.6 versus 4.3) migraine days and acute medication days (7.9 versus 10.0) were not substantially different at baseline. The percentage of patients with at least a 50% reduction in the frequency of moderate or severe headache days was 30% for both groups (10/30 vs nine of 30, Δ 0.00, 95% CI –0.22 to 0.23). Conclusions Greater ONB does not reduce the frequency of moderate to severe migraine days in patients with episodic or chronic migraine compared to placebo. The study was registered with ClinicalTrial.gov (NCT00915473).


Neuromodulation | 2013

Long‐Term Outcome in Occipital Nerve Stimulation Patients With Medically Intractable Primary Headache Disorders

Ann Chang Brewer; Terrence L. Trentman; Michael G. Ivancic; Bert B. Vargas; Alanna M. Rebecca; Richard S. Zimmerman; David M. Rosenfeld; David W. Dodick

Introduction:  Occipital nerve stimulation (ONS) may provide relief for refractory headache disorders. However, scant data exist regarding long‐term ONS outcomes.


Seminars in Neurology | 2010

Cluster Headache: Diagnosis and Treatment

Rashmi Halker; Bert B. Vargas; David W. Dodick

Cluster headache is a rare yet exquisitely painful primary headache disorder occurring in either episodic or chronic patterns. The unique feature of cluster headache is the distinctive circadian and circannual periodicity in the episodic forms. The attacks are stereotypic--they are of extreme intensity and short duration, occur unilaterally, and are associated with robust signs and symptoms of autonomic dysfunction. Although the pathophysiology of cluster headache remains to be fully understood, there have been a number of recent seminal observations. To exclude structural mimics, patients presenting with symptoms suggestive of cluster headache warrant at least a brain magnetic resonance imaging (MRI) scan in their work-up. The medical treatment of cluster headache includes acute, transitional, and maintenance prophylaxis. Agents used for acute therapy include inhalation of oxygen, triptans, such as sumatriptan, and dihydroergotamine. Transitional prophylaxis refers to the short-term use of fast-acting agents. This typically involves either corticosteroids or an occipital nerve block. The mainstay of prophylactic therapy is verapamil. Yet, other medications, including lithium, divalproex sodium, topiramate, methysergide, gabapentin, and even indomethacin, may be useful when the headache fails to respond to verapamil. For medically refractory patients, surgical interventions, occipital nerve stimulation, and deep brain stimulation remain an option. As the sophistication of functional neuroimaging increases, better insight into the pathophysiological mechanisms that underlie cluster headache is expected.


Neurologic Clinics | 2009

The Face of Chronic Migraine: Epidemiology, Demographics, and Treatment Strategies

Bert B. Vargas; David W. Dodick

Chronic daily headache (CDH) represents a therapeutic challenge for many clinicians. Treatment strategies should be aimed at correctly identifying the presence of CDH. In addition, an effective prophylactic regimen should be initiated; the presence of medication overuse must be addressed, and the offending medication being overused must be discontinued. Aside from analgesic overuse, other modifiable risk factors associated with the development of chronic migraine and CDH must be addressed including obesity and caffeine use and the effective management of comorbid conditions such as depression, anxiety, and sleep-related breathing disorders.


Neurology | 2013

Sensitivity of MRI of the spine compared with CT myelography in orthostatic headache with CSF leak

Amaal J. Starling; Fatima Hernandez; Joseph M. Hoxworth; Terrence L. Trentman; Rashmi Halker; Bert B. Vargas; Eric V. Hastriter; David W. Dodick

Objective: To investigate the sensitivity of MRI of the spine compared with CT myelography (CTM) in detecting CSF leaks. Methods: Between July 1998 and October 2010, 12 patients with orthostatic headache and a CTM-confirmed spinal CSF leak underwent an MRI of the spine with and without contrast. Using CTM as the gold standard, we retrospectively investigated the sensitivity of spinal MRI in detecting a CSF leak. Results: Eleven of 12 patients with a CSF leak documented by CTM also had extradural fluid collections on spinal MRI (sensitivity 91.7%). Six patients with extradural fluid collections on spinal MRI also had spinal dural enhancement. Conclusion: When compared with the gold standard of CTM, MRI of the spine appears to be a sensitive and less invasive imaging modality for detecting a spinal CSF leak, suggesting that MRI of the spine should be the imaging modality of first choice for the detection of spinal CSF leaks.


The Neurologist | 2011

Risk of development of medication overuse headache with nonsteroidal anti-inflammatory drug therapy for migraine: a critically appraised topic.

Amaal J. Starling; Charlene Hoffman-Snyder; Rashmi Halker; Kay E. Wellik; Bert B. Vargas; David W. Dodick; Bart M. Demaerschalk; Dean M. Wingerchuk

Background:The development of medication overuse headache (MOH) is associated with frequent use of analgesics, especially opiates, for treatment of primary headache disorders, particularly migraine. Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat migraine. Objective:To critically evaluate evidence estimating the risk of MOH associated with NSAID therapy in patients with migraine. Methods:The objective was addressed through the development of a structured, critically appraised topic. This included a clinical scenario, structured question, literature search strategy, critical appraisal, results, evidence summary, commentary, and bottom line conclusions. Participants included consultant and resident neurologists, a medical librarian, clinical epidemiologists, and headache neurology content experts. Results:The 1-year incidence of MOH was 2.5%. In patients with low (0 to 4 d monthly) to moderate (5 to 9 d monthly) baseline headache frequency, NSAIDs were not associated with progression to MOH and may be protective (odds ratio=0.31; 95% confidence interval, 0.27-0.34). However, in patients with a high baseline headache frequency (10 to 14 d monthly), NSAIDs are associated with progression to MOH (odds ratio=1.93; 95% confidence interval, 1.82-2.06). Conclusions:Acute NSAID therapy is associated with progression to MOH in migraineurs with a high baseline migraine frequency but may be protective in patients with low baseline headache frequency. However, a causal role for NSAIDs in progression from episodic to chronic headache has not been established.


Current Pain and Headache Reports | 2013

Primary Exertional Headache: Updates in the Literature

Rashmi Halker; Bert B. Vargas

Primary exertional headache (PEH) has been recognized by the International Headache Society as a primary headache diagnosis since 1994. It is an uncommon, self-limited, and short-lasting disorder that is precipitated by exertion and is frequently comorbid with migraine. PEH shares a number of features with other headache disorders, including thunderclap headache, primary cough headache, and headache associated with sexual activity. Upon its initial occurrence, PEH requires a thorough neurologic evaluation and imaging studies to help eliminate possible underlying secondary causes, including subarachnoid hemorrhage and sentinel bleed. Although PEH is incompletely understood with regard to its epidemiology and pathophysiology, it is generally considered to be a benign disorder that is self-limited and responsive to trigger avoidance and indomethacin.


Journal of Neurosurgical Anesthesiology | 2010

Occipital nerve stimulator placement under general anesthesia: initial experience with 5 cases and review of the literature.

Terrence L. Trentman; Richard S. Zimmerman; David W. Dodick; Carla L. Dormer; Bert B. Vargas

Anesthesiologists support nerve stimulator insertion procedures, including occipital nerve stimulator placement for refractory headache disorders. Sedation during these cases can be challenging on account of variable surgical stimuli and surgery positioning that contribute to neck flexion, potentially compromising the airway. Greater patient comfort and safety may be found in performing permanent occipital stimulator placement procedures entirely under general anesthesia, assuming that appropriate stimulation patterns can be achieved in patients who are unable to provide intraoperative feedback. The purpose of this study is to describe our initial experience with occipital nerve stimulator placement performed entirely under general anesthesia and the resulting stimulation patterns, and to review the medical literature regarding the anesthetic techniques used during these novel neurosurgical procedures. After institutional review board approval, we reviewed the records of 5 patients who underwent permanent occipital nerve stimulator placement under general anesthesia. Appropriateness of the postoperative stimulation patterns was noted in addition to complications. The medical literature was searched for occipital stimulation surgery studies that also described the anesthetic technique. We found that all 5 patients underwent uncomplicated general anesthetics. Postoperative occipital stimulation was nonpainful and symmetrical for all. The literature search provided little information on the anesthetic technique; most procedures were performed at least in part under local anesthesia with sedation. On the basis of this small case series, we conclude that the occipital nerve stimulator systems can be successfully placed under general anesthesia while still achieving the desired occipital region stimulation. Further studies are needed to correlate occipital nerve stimulator placement under general anesthesia and long-term headache control.

Collaboration


Dive into the Bert B. Vargas's collaboration.

Researchain Logo
Decentralizing Knowledge