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Dive into the research topics where John G. Frazee is active.

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Featured researches published by John G. Frazee.


Neurology | 2003

Acute seizures after intracerebral hemorrhage A factor in progressive midline shift and outcome

Paul Vespa; Kristine O'Phelan; M. Shah; J. Mirabelli; Sidney Starkman; Chelsea S. Kidwell; Jeffrey L. Saver; Marc R. Nuwer; John G. Frazee; D. A. McArthur; Neil A. Martin

Objective: To determine whether early seizures that occur frequently after intracerebral hemorrhage (ICH) lead to increased brain edema as manifested by increased midline shift. Methods: A total of 109 patients with ischemic stroke (n = 46) and intraparenchymal hemorrhage (n = 63) prospectively underwent continuous EEG monitoring after admission. The incidence, timing, and factors associated with seizures were defined. Serial CT brain imaging was conducted at admission, 24 hours, and 48 to 72 hours after hemorrhage and assessed for hemorrhage volume and midline shift. Outcome at time of discharge was assessed using the Glasgow Outcome Scale score. Results: Electrographic seizures occurred in 18 of 63 (28%) patients with ICH, compared with 3 of 46 (6%) patients with ischemic stroke (OR = 5.7, 95% CI 1.4 to 26.5, p < 0.004) during the initial 72 hours after admission. Seizures were most often focal with secondary generalization. Seizures were more common in lobar hemorrhages but occurred in 21% of subcortical hemorrhages. Posthemorrhagic seizures were associated with neurologic worsening on the NIH Stroke Scale (14.8 vs 18.6, p < 0.05) and with an increase in midline shift (+ 2.7 mm vs −2.4 mm, p < 0.03). There was a trend toward increased poor outcome (p < 0.06) in patients with posthemorrhagic seizures. On multivariate analysis, age and initial NIH Stroke Scale score were independent predictors of outcome. Conclusion: Seizures occur commonly after ICH and may be nonconvulsive. Seizures are independently associated with increased midline shift after intraparenchymal hemorrhage.


Neurology | 2001

Diffusion-perfusion MR evaluation of perihematomal injury in hyperacute intracerebral hemorrhage

Chelsea S. Kidwell; Jeffrey L. Saver; James Mattiello; Steven Warach; David S. Liebeskind; Sidney Starkman; Paul Vespa; J. P. Villablanca; Neil A. Martin; John G. Frazee; Jeffry R. Alger

Background: It has been suggested that a zone of perihematomal ischemia analogous to an ischemic penumbra exists in patients with primary intracerebral hemorrhage (ICH). Diffusion-perfusion MRI provides a novel means of assessing injury in perihematomal regions in patients with ICH. Objective: To characterize diffusion-perfusion MRI changes in the perihematomal region in patients with hyperacute intracerebral hemorrhage. Method: Twelve patients presenting with hyperacute, primary ICH undergoing CT scanning and diffusion-perfusion MRI within 6 hours of symptom onset were reviewed. An automated thresholding technique was used to identify decreased apparent diffusion coefficient (ADC) values in the perihematomal regions. Perfusion maps were examined for regions of relative hypo- or hyperperfusion. Results: Median baseline NIH Stroke Scale score was 17 (range, 6 to 28). Median hematoma volume was 13.3 mL (range, 3.0 to 74.8 mL). MRI detected the hematoma in all patients on echo-planar susceptibility-weighted imaging and in all seven patients imaged with gradient echo sequences. In six patients who underwent perfusion imaging, no focal defects were visualized on perfusion maps in tissues adjacent to the hematoma; however, five of six patients demonstrated diffuse ipsilateral hemispheric hypoperfusion. On diffusion imaging, perihematomal regions of decreased ADC values were identified in three of 12 patients. All three subsequently showed clinical and radiologic deterioration. Conclusions: A rim of perihematomal decreased ADC values was visualized in the hyperacute period in a subset of patients with ICH. The presence of a rim of decreased ADC outside the hematoma correlated with poor clinical outcome. Although perfusion maps did not demonstrate a focal zone of perihematomal decreased blood flow in any patient, most patients had ipsilateral hemispheric hypoperfusion.


Neurosurgery | 2008

Application of neuroendoscopy to intraventricular lesions.

P. Cappabianca; Giuseppe Cinalli; Michelangelo Gangemi; Andrea Brunori; Luigi Maria Cavallo; E. de Divitiis; Philippe Decq; Alberto Delitala; F. Di Rocco; John G. Frazee; Umberto Godano; André Grotenhuis; Pierluigi Longatti; Carmelo Mascari; T. Nishihara; Shizuo Oi; Harold L. Rekate; Henry W. S. Schroeder; Mark M. Souweidane; Pietro Spennato; G. Tamburrini; Charles Teo; Benjamin C. Warf; Samuel Tau Zymberg

We present an overview of the history, development, technological advancements, current application, and future trends of cranial endoscopy. Neuroendoscopy provides a safe and effective management modality for the treatment of a variety of intracranial disorders, either tumoral or non-tumoral, congenital, developmental, and degenerative, and its knowledge, indications, and limits are fundamental for the armamentarium of the modern neurosurgeon.


Neurocritical Care | 2005

Frameless stereotactic aspiration and thrombolysis of deep intracerebral hemorrhage is associated with reduction of hemorrhage volume and neurological improvement.

Paul Vespa; David L. McArthur; Chad Miller; Kristine O'Phelan; John G. Frazee; Chelsea S. Kidwell; J Saver; Sidney Starkman; Neil A. Martin

Introduction: This ia a phase-2 safety trial to demonstrate the ability of frameless stereotactic aspiration and thrombolysis of ICH to safely remove blood.Methods: Patients with ICH in the deep basal ganglia and internal capsule of >5 cc volume were consented to undergo computed tomographic imaging for frameless stereotactic guidance registration. Using the frameless stereotactic (CT) guidance, a 4-mm diameter catheter was inserted into the body of the hematoma using a frontal burr hole approach. The catheter was aspirated and then flushed with saline and aspirated to remove unclotted blood. After a confirmatory CT scan to localize the catheter, 1 mg of recombinant tissue plasminogen activator (t-PA) was infused into the clot, permitted to bathe the clot for 30 minutes, and then drained into a closed circuit collection system. t-PA was infused every 8 hours for 48 hours. A follow up CT scan was obtained at 48 hours.Results: 28 patients with ICH (mean age 67.1) were admitted and underwent the procedure. Mean initial ICH volume was 54.6 cc ± 37.8. Mean time from onset to aspiration was 44 hours (range 7–180). Mean initial NIH Stroke scale (NIHSS) score was 24 (range 15–33). Compared with initial CT scan, there was a mean reduction of ICH volume by 77 ± 13% on final CT scan (p<0.0002). Compared with initial NIHSS, the discharge mean NIHSS (16 ± 6) was significantly improved (p<0.001). There were no infectious, hemodynamic or neurologic complications. There were no episodes of symptomatic hemorrhagic enlargement and one case of asymptomatic bleeding along the catheter tract.Conclusion: Frameless stereotactic aspiration and thrombolysis (FAST) of deep spontaneous intracerebral hemorrhage is a safe therapy that is associated with reduction in ICH volume, early improvement in NIHSS and potentially could be used to improve outcome.


Stroke | 1987

Functional arterial changes in chronic cerebrovasospasm in monkeys: an in vitro assessment of the contribution to arterial narrowing.

John A. Bevan; Rosemary D. Bevan; John G. Frazee

Cerebral arteries from monkeys with chronic cerebral vasospasm arising from experimental subarachnoid hemorrhage produced 5-6 days previously were examined for changes in their functional properties in an attempt to understand the basis of the narrowing. Hemorrhage was caused by puncture of the internal carotid artery just proximal to the circle of Willis. Segments taken close to the origins of the anterior and middle cerebral arteries consistently showed decreased distensibility. In addition, they exhibited large, prolonged, spontaneous increases in muscle tone. Other alterations observed include a marked reduction in the capacity of the vessel wall to contract, reduction in constrictor and dilator nerve influences on vascular tone, and some increased sensitivity to serotonin. Small pial arteries (150-200 micron o.d.) from the side of the injury showed large spontaneous irregular increases in tone. It is proposed that 5-6 days after experimental subarachnoid hemorrhage in monkeys the change most responsible for persistent narrowing in the larger arteries is an increased rigidity of the vessel wall. This is probably caused by an inflammatory response. In the smaller arteries, abnormal spontaneous contractile activity is a major factor in narrowing. This activity is not stretch-dependent. We suggest that the initial cause of the arterial narrowing after hemorrhage is the action of vasoactive substances released in the close vicinity of the arterial wall, which lead to tissue damage, abnormal tone, and an inflammatory response with fibrosis.


Neurosurgery | 1999

Endoscopic resection of colloid cysts: surgical considerations using the rigid endoscope.

Wesley A. King; Jamie S. Ullman; John G. Frazee; Kalmon D. Post; Marvin Bergsneider

OBJECTIVE Colloid cysts of the third and lateral ventricles have traditionally been treated by transfrontal and transcallosal microsurgical resection or by stereotactic aspiration. Recently, rigid and flexible ventricular endoscopic techniques have been used to treat these lesions. Our study was undertaken to examine the efficacy of rigid endoscopy in the resection of colloid cysts. METHODS Fifteen patients with a radiological diagnosis of colloid cysts were given the option of undergoing either endoscopic surgery or craniotomy. The average tumor size was 1.43 cm. Fourteen patients underwent planned endoscopic resections, and a craniotomy was performed initially in one patient. RESULTS Entire tumor resection was achieved with the endoscope in 12 patients (86%). A craniotomy was required for two colloid cysts that could not be resected endoscopically. In total, complete radiographic resections were achieved in 14 patients (93%). There were no permanent complications, although postoperative deficits included short-term memory loss and hemiparesis, each in one patient. CONCLUSION Rigid endoscopy affords good optical resolution, high magnification, and excellent illumination. Total or near total resection of colloid cysts should be the goal for all patients and can be achieved using the rigid endoscope, with little morbidity, shortened operative time, reduced length of stay, and resolution of symptoms. Although long-term follow-up is needed, we think that endoscopy should be considered as a primary treatment for most patients.


Surgical Neurology | 2008

Image-guided endoscopic evacuation of spontaneous intracerebral hemorrhage☆

Chad Miller; Paul Vespa; Jeffrey L. Saver; Chelsea S. Kidwell; Stanley Thomas Carmichael; Jeffry R. Alger; John G. Frazee; David S. Liebeskind; Valeriy Nenov; Robert Elashoff; Neil A. Martin

BACKGROUND Spontaneous ICH is a devastating disease with high morbidity and mortality. Intracerebral hemorrhage lacks an effective medical or surgical treatment despite the acknowledged pathophysiologic benefits of achieved hemostasis and clot removal. Image-guided stereotactic endoscopic hematoma evacuation is a promising minimally invasive approach designed to limit operative injury and maximize hematoma removal. METHODS A single-center randomized controlled trial was designed to assess the safety and efficacy of stereotactic hematoma evacuation compared to best medical management. Patients were randomized within 24 hours of hemorrhage in a 3:2 fashion to best medical management plus endoscopic hematoma evacuation or best medical management alone. Data were collected to assess efficacy and safety of hematoma evacuation and to identify procedural components requiring technical improvement. RESULTS Ten patients have been enrolled and randomized to treatment. Six patients underwent endoscopic evacuation with a hematoma volume reduction of 80% +/- 13% at 24 hours post procedure. The medical arm demonstrated a hematoma enlargement of 78% +/- 142% during this same period. Rehemorrhage rates and deterioration rates were similar in the 2 groups. Mortality was 20% in the endoscopic group and 50% in the medical treatment cohort. The endoscopic technique was shown to be effective in identification and evacuation of hematomas, whereas reduction in the number of endoscopic passes and maintenance of hemostasis require further study. CONCLUSION Image-guided stereotactic endoscopic hematoma removal is a promising minimally invasive technique that is effective in immediate hematoma evacuation. This technique deserves further investigation to determine its role in ICH management.


Stroke | 1998

Retrograde Transvenous Neuroperfusion: A Back Door Treatment for Stroke

John G. Frazee; Xia Luo; Guoming Luan; David S. Hinton; David A. Hovda; Mark S. Shiroishi; Larry T. Barcliff

BACKGROUND AND PURPOSE Stroke is the third leading cause of death and the leading cause of adult disability in the United States. The clot-lysis drug tissue plasminogen activator is the only treatment that has been effective for acute stroke patients, yet there are significant limitations to its use and effectiveness. In this study retrograde transvenous neuroperfusion (RTN) was evaluated for its efficacy in reversing acute ischemia, preventing paralysis, and limiting pathological evidence of infarction in baboons. METHODS Ten adult male baboons underwent 3.5 hours of reversible middle cerebral artery occlusion (MCAO) under isoflurane (0.25% to 1.5%) anesthesia. Five randomly chosen animals received RTN treatment 1 hour after start of MCAO. Somatosensory evoked potentials were recorded during MCAO. Animals were assigned daily neurological scores. Animals were killed 6 days after MCAO, and brains were quantitatively analyzed for infarct volume. RESULTS Within 1 hour after RTN was started, treated animals showed significantly improved somatosensory evoked potentials (103.3% versus 75% of baseline; P<0.01). Likewise, the combined neurological score for the RTN-treated group was 99.2, while the combined mean score for the untreated group was 66.4 (P<0.015). The mean infarction volume was 8.8+/-3.1% (of contralateral hemisphere) for the control group and 0.3+/-0.2% for the RTN-treated group (P<0.01). No increased mortality was seen in the RTN-treated group. CONCLUSIONS We conclude that RTN treatment during MCAO effectively reverses the pathophysiological sequelae of ischemia, even when the treatment is initiated 1 hour after the onset of ischemia. Although the infarct volume in the control group was variable when quantitatively assessed 6 days after 3.5 hours of MCAO, virtually no evidence of infarcts was seen in the RTN-treated group.


Neurosurgery | 1980

Subdural Empyema—Importance of Early Diagnosis

Justin W. Renaudin; John G. Frazee

Because subdural empyema (SDE) is an unusual central nervous system infection, recognition is not always prompt. Consequently delays can allow a serious but curable infection to become irreparably damaging or even fatal. This condition, particularly in the early stages, is relatively easy to treat. Personal experience with six patients during the past 3 years promoted us to review the data from UCLA and its affiliated hospitals. Among the 23 cases of SDE reviewed, the predisposing factor in 16 was sinusitis, mastoiditis, or otitis media. The clinical presentation, encompassing a systemic febrile illness, headache, and neurological deficit, was monotonously uniform. The high incidence of paranasal sinus involvement in the adult, middle ear infections in infants, and seizures in 15 patients comprised further clinical clues suggesting the diagnosis. Although usually diagnosed as an intracranial inflammatory process, an initial failure to suspect a purulent collection in the subdural compartment was typical. Although the findings of definitive diagnostic studies (computed tomography or angiography) are strikingly positive in advanced cases, in the earlier stages of this disorder they may be subtly abnormal. Because the mortality and morbidity rates, in some measure, depend on the stage at which the process is arrested, the real challenge lies in making a prompt diagnosis. The most favorable results are associated with early, decisive surgical treatment.


Neurosurgery | 2009

Management of giant middle cerebral artery aneurysms with incorporated branches: partial endovascular coiling or combined extracranial-intracranial bypass--a team approach.

Zhong-Song Shi; Jordan Ziegler; Gary Duckwiler; Reza Jahan; John G. Frazee; James I. Ausman; Neil A. Martin; Fernando Viñuela

OBJECTIVE Our goal was to assess the long-term anatomic and clinical outcomes in patients with giant middle cerebral artery (MCA) aneurysms treated by endovascular coil embolization alone or in combination with cerebral revascularization. METHODS One hundred twenty-six patients with giant intracranial aneurysms were endovascularly treated at the University of California, Los Angeles, between 1990 and 2007. Of these, 9 patients had partially thrombosed MCA aneurysms with incorporated branches. Five patients presented with symptoms of mass effect, 3 had seizures, 2 had episodes of brain ischemia, and 1 presented with acute subarachnoid hemorrhage. RESULTS Three wide-neck saccular aneurysms were almost completely coil occluded, leaving only small neck remnants that were intended to preserve the patency of incorporated MCA branches. The other 6 fusiform aneurysms were effectively treated by superficial temporal artery-MCA or occipital artery-MCA bypass, followed by complete coil occlusion of these aneurysms. Immediate angiograms and mid- or long-term neuroradiological imaging follow-up examinations revealed complete obliteration or near-complete occlusion (90%–99%) of the aneurysms in all 9 patients. Seven patients had a favorable long-term clinical outcome, and 1 patient died as a result of unrelated congestive heart failure. One patient required emergent surgical aneurysm thrombectomy because of inadvertent coil occlusion of the frontal opercular artery, which was not protected by the bypass, and the patient subsequently sustained a moderate neurological disability. CONCLUSION Giant MCA aneurysms with branch incorporations and other unfavorable features such as intraluminal thrombus, mural calcification, and fusiform configuration can be effectively treated with a team approach, using coil embolization after protective surgical bypass. When aneurysms with MCA branches incorporated into the neck rather than the dome are treated by endovascular techniques alone, long-term angiographic follow-up is necessary to assess and further treat any significant remnant.

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Neil A. Martin

University of California

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Gary Duckwiler

University of California

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Paul Vespa

University of California

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Reza Jahan

University of California

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