Rafael Tamargo | Johns Hopkins University (original) (raw)

Papers by Rafael Tamargo

Research paper thumbnail of Cocaine use as an independent predictor of seizures after aneurysmal subarachnoid hemorrhage

Journal of Neurosurgery, 2016

OBJECT Seizures are relatively common after aneurysmal subarachnoid hemorrhage (aSAH). Seizure pr... more OBJECT Seizures are relatively common after aneurysmal subarachnoid hemorrhage (aSAH). Seizure prophylaxis is controversial and is often based on risk stratification; middle cerebral artery (MCA) aneurysms, associated intracerebral hemorrhage (ICH), poor neurological grade, increased clot thickness, and cerebral infarction are considered highest risk for seizures. The purpose of this study was to evaluate the impact of recent cocaine use on seizure incidence following aSAH. METHODS Prospectively collected data from aSAH patients admitted to 2 institutional neuroscience critical care units between 1991 and 2009 were reviewed. The authors analyzed factors that potentially affected the incidence of seizures, including patient demographic characteristics, poor clinical grade (Hunt and Hess Grade IV or V), medical comorbidities, associated ICH, intraventricular hemorrhage (IVH), hydrocephalus, aneurysm location, surgical clipping and cocaine use. They further studied the impact of these ...

Research paper thumbnail of Preoperative Anemia Increases Postoperative Complications and Mortality Following Total Joint Arthroplasty

The Journal of Arthroplasty, 2015

Research paper thumbnail of Cocaine Use Is an Independent Risk Factor for Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

Stroke, 2001

Background and Purpose — Although acute cocaine use has been temporally associated with aneurysma... more Background and Purpose — Although acute cocaine use has been temporally associated with aneurysmal subarachnoid hemorrhage (aSAH), the prevalence of vasospasm and the clinical outcome of patients experiencing aSAH associated with cocaine exposure are unclear. We have analyzed this patient population in our institution to address these issues. Methods — Between 1992 and 1999, 440 patients presented to our institution with aSAH. This sample was retrospectively analyzed to determine which patients had used cocaine within 72 hours of aSAH as documented by urine toxicology studies or patient history. These patients were then compared with control aSAH patients without recent cocaine exposure through univariable and multivariable analyses. Results — Twenty-seven aSAH patients (6.1% of total) had either urine toxicology positive for cocaine metabolites (20 patients, 74%) or a history of cocaine use within 72 hours of aSAH (7 patients, 26%). Cocaine users were more likely to experience cere...

Research paper thumbnail of Risk Factors for Subarachnoid Hemorrhage

Neurosurgery, 2001

OBJECTIVE: Cigarette smoking has been demonstrated to increase the risk of subarachnoid hemorrhag... more OBJECTIVE: Cigarette smoking has been demonstrated to increase the risk of subarachnoid hemorrhage (SAH). Whether cessation of smoking decreases this risk remains unclear. We performed a case-control study to examine the effect of smoking and other known risk factors for cerebrovascular disease on the risk of SAH. METHODS: We reviewed the medical records of all patients with a diagnosis of SAH (n ‫؍‬ 323) admitted to Johns Hopkins Hospital between January 1990 and June 1997. Controls matched for age, sex, and ethnicity (n ‫؍‬ 969) were selected from a nationally representative sample of the Third National Health and Nutrition Examination Survey. We determined the independent association between smoking (current and previous) and various cerebrovascular risk factors and SAH by use of multivariate logistic regression analysis. A separate analysis was performed to determine associated risk factors for aneurysmal SAH. RESULTS: Of 323 patients admitted with SAH (mean age, 52.7 ؎ 14 yr; 93 were men), 173 (54%) were hypertensive, 149 (46%) were currently smoking, and 125 (39%) were previous smokers. In the multivariate analysis, both previous smoking (odds ratio [OR], 4.5; 95% confidence interval [CI], 3.1-6.5) and current smoking (OR, 5.2; 95% CI, 3.6-7.5) were significantly associated with SAH. Hypertension was also significantly associated with SAH (OR, 2.4; 95% CI, 1.8-3.1). The risk factors for 290 patients with aneurysmal SAH were similar and included hypertension (OR, 2.4; 95% CI, 1.8-3.2), previous smoking (OR, 4.1; 95% CI, 2.7-6.0), and current smoking (OR, 5.4; 95% CI, 3.7-7.8). CONCLUSION: Hypertension and cigarette smoking increase the risk for development of SAH, as found in previous studies. However, the increased risk persists even after cessation of cigarette smoking, which suggests the importance of early abstinence from smoking.

Research paper thumbnail of Intraoperative indocyanine green angiography for microsurgical treatment of a craniocervical dural arteriovenous fistula

Clinical Neurology and Neurosurgery, 2012

Spinal dural arteriovenous fistulas (DAVF) may arise anywhere etween foramen magnum and sacrum ac... more Spinal dural arteriovenous fistulas (DAVF) may arise anywhere etween foramen magnum and sacrum accounting for the majority f spinal vascular malformations. Most spinal DAVF are localized t the thoracolumbar junction while DAVF at the craniocervial level are a true exception. The main goal of treatment is the omplete obliteration of the fistula. The use of indocyanine green ICG) videoangiography has been introduced for the treatment of erebrovascular diseases by Raabe and colleagues in 2003 [1]. By ow, it has developed to a technique which has greatly enhanced ntraoperative options of imaging vascular structures like cerebral neurysms. Here we report the case of a patient with DAVF at the craniocerical junction who was referred to our centre after a failed attempt f endovascular embolization at an outside institution. We describe he use of intraoperative ICG angiography to identify the fistula and onfirm its successful obliteration.

Research paper thumbnail of Reprint

Circulation, 2007

Purpose— The aim of this statement is to present current and comprehensive recommendations for th... more Purpose— The aim of this statement is to present current and comprehensive recommendations for the diagnosis and treatment of acute spontaneous intracerebral hemorrhage. Methods— A formal literature search of Medline was performed through the end date of August 2006. The results of this search were complemented by additional articles on related issues known to the writing committee. Data were synthesized with the use of evidence tables. The American Heart Association Stroke Council’s Levels of Evidence grading algorithm was used to grade each recommendation. Prerelease review of the draft guideline was performed by 5 expert peer reviewers and by the members of the Stroke Council Leadership Committee. It is intended that this guideline be fully updated in 3 years’ time. Results— Evidence-based guidelines are presented for the diagnosis of intracerebral hemorrhage, the management of increased arterial blood pressure and intracranial pressure, the treatment of medical complications of ...

Research paper thumbnail of True posterior communicating artery aneurysm

Acta Neurologica Scandinavica, 1991

Research paper thumbnail of Epidemiology and outcomes of pediatric intracranial aneurysms: comparison with an adult population in a 30-year, prospective database

Journal of Neurosurgery: Pediatrics, 2021

OBJECTIVE Pediatric intracranial aneurysms are rare. Most large series in the last 15 years repor... more OBJECTIVE Pediatric intracranial aneurysms are rare. Most large series in the last 15 years reported on an average of only 39 patients. The authors sought to report their institutional experience with pediatric intracranial aneurysms from 1991 to 2021 and to compare pediatric patient and aneurysm characteristics with those of a contemporaneous adult cohort. METHODS Pediatric (≤ 18 years of age) and adult patients with one or more intracranial aneurysms were identified in a prospective database. Standard epidemiological features and outcomes of each pediatric patient were retrospectively recorded. These results were compared with those of adult aneurysm patients managed at a single institution over the same time period. RESULTS From a total of 4500 patients with 5150 intracranial aneurysms admitted over 30 years, there were 47 children with 53 aneurysms and 4453 adults with 5097 aneurysms; 53.2% of children and 36.4% of adults presented with a subarachnoid hemorrhage (SAH). Pediatric...

Research paper thumbnail of 47 Consecutive Cases of Pipeline Flex Flow Diversion Utilizing a Novel Large-Bore Intracranial Intermediate Catheter: Nuances and Institutional Experience with the Syphontrak

Interventional neurology, 2018

The increasing complexity of modern neurointerventions has necessitated a shift in intracranial a... more The increasing complexity of modern neurointerventions has necessitated a shift in intracranial access techniques towards more robust distal support platforms. Here we present our experience with the Syphontrak Support Catheter (Codman Neuro, Raynham, MA, USA) in the triaxial platform for the implantation of the second-generation Pipeline Flex embolization device (PED Flex; Medtronic Neurovascular, Irvine, CA, USA). We retrospectively identified patients who underwent PED Flex treatment utilizing the Syphontrak at a single institution. The procedural data collected included parent artery tortuosity, patient demographics, aneurysm characteristics, other equipment utilized, and catheter-related complications. A total of 47 consecutive aneurysm flow diversions were successfully performed using the Syphontrak. The patients' age ranged from 25 to 80 years (mean 57.3 ± 11.6) and 85% were women. The average aneurysm size was 4.8 ± 2.7 mm (range 2-14). All cases were in the anterior cir...

Research paper thumbnail of Abciximab (ReoPro) Dosing Strategy for the Management of Acute Intraprocedural Thromboembolic Complications during Pipeline Flow Diversion Treatment of Intracranial Aneurysms

Interventional neurology, 2018

Flow diversion with the Pipeline embolization device (PED) is an effective neuro-endovascular met... more Flow diversion with the Pipeline embolization device (PED) is an effective neuro-endovascular method and increasingly accepted for the treatment of cerebral aneurysms. Acute in situ thrombosis is a known complication of PED procedures. There is limited experience in the flow diversion literature on the use of abciximab (ReoPro) for the management of acute thrombus formation in PED cases. Data were collected retrospectively on patients who received intra-arterial (IA) ReoPro with or without subsequent intravenous (IV) infusion during PED flow diversion treatment of intracranial aneurysms. A total of 30 cases in patients with a mean age of 56.7 years (range 36-84) and a mean aneurysm size of 8.6 mm (range 2-25) were identified to have intraprocedural thromboembolic complications during PED treatment. IA ReoPro was administered in all cases, with 20 cases receiving increments of 5-mg boluses and 10 cases receiving a 0.125 mg/kg IA bolus (half cardiac dosing). Complete or partial recana...

Research paper thumbnail of Procedural complexity independent of P2Y12 reaction unit (PRU) values is associated with acute in situ thrombosis in Pipeline flow diversion of cerebral aneurysms

Stroke and vascular neurology, 2018

Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device (PED) pro... more Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device (PED) procedures with potentially high morbidity and mortality. There is controversy regarding the role of platelet function testing with P2Y12 assay as a predictor of intraprocedural thromboembolic events. There is limited knowledge on whether procedural complexity influences these events. Data were collected retrospectively on 742 consecutive PED cases at a single institution. Patients with intraprocedural acute thrombosis were compared with patients without these events. A cohort of 37 PED cases with acute in situ thrombosis (mean age 53.8 years, mean aneurysm size 8.4 mm) was matched with a cohort of 705 PED cases without intraprocedural thromboembolic events (mean age 56.4 years, mean aneurysm size 6.9 mm). All patients with in situ thrombosis received intra-arterial and/or intravenous abciximab. The two groups were evenly matched in patient demographics, previous treatment/subarachnoid hemo...

Research paper thumbnail of Pipeline Embolization for Salvage Treatment of Previously Stented Residual and Recurrent Cerebral Aneurysms

Interventional neurology, 2018

This study assessed the safety and effectiveness of the Pipeline embolization device (PED) for pe... more This study assessed the safety and effectiveness of the Pipeline embolization device (PED) for persistent and recurrent aneurysms previously treated with either a vascular reconstruction device (VRD) or a flow diverter (FD). A prospective, IRB-approved database was analyzed for patients treated with PED for aneurysms previously treated with a stent. Twenty procedures were performed on 18 patients, 11 with prior FD, 7 with VRD, and 2 previously treated with both. Overall, 15 aneurysms were saccular (75%), and size was 13.5 ± 7.6 mm. Location was internal carotid artery (ICA) in 14 cases (70%) and posterior circulation in 6 cases (30%). Average prior treatments were 1.7. Previously FD cases were re-treated at an average of 18.1 months from most recent treatment. Each case used 1 device, 82% with distal coverage and 82% with proximal coverage of prior stent. Balloon remodeling was performed in 3 cases (27%) and no in-stent thrombosis was observed. Previously VRD stent-coiled cases were...

Research paper thumbnail of Pipeline-assisted coil embolization of a large middle cerebral artery pseudoaneurysm in a 9-month-old infant: experience from the youngest flow diversion case

Journal of neurosurgery. Pediatrics, Jan 24, 2018

Intracranial aneurysms in the pediatric population are rare entities. The authors recently treate... more Intracranial aneurysms in the pediatric population are rare entities. The authors recently treated a 9-month-old infant with a 19-mm recurrent, previously ruptured, and coil-embolized left middle cerebral artery (MCA) pseudoaneurysm, which was treated definitively with single-stage Pipeline-assisted coil embolization. The patient was 5 months old when she underwent resection of a left temporal Grade 1 desmoplastic infantile ganglioglioma at an outside institution, which was complicated by left MCA injury with a resultant 9-mm left M pseudoaneurysm. Within a month, the patient had two aneurysmal rupture events and underwent emergency craniectomy for decompression and evacuation of subdural hematoma. The pseudoaneurysm initially underwent coil embolization; however, follow-up MR angiography (MRA) revealed aneurysm recanalization with saccular enlargement to 19 mm. The patient underwent successful flow diversion-assisted coil embolization at 9 months of age. At 7 months after the proce...

Research paper thumbnail of Predictors of cerebral aneurysm persistence and occlusion after flow diversion: a single-institution series of 445 cases with angiographic follow-up

Journal of neurosurgery, Jan 30, 2018

OBJECTIVE Flow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The ... more OBJECTIVE Flow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The existing literature on aneurysm occlusion is limited by heterogeneous follow-up, variable antiplatelet regimens, noninvasive imaging modalities, and nonstandard occlusion assessment. Using a large, single-center cohort with low attrition and standardized antiplatelet tapering, the authors evaluated outcomes after flow diversion of anterior circulation aneurysms to identify predictors of occlusion and aneurysm persistence. METHODS Data from a prospective, IRB-approved database was analyzed for all patients with anterior circulation aneurysms treated by flow diversion with the Pipeline embolization device (PED) at the authors' institution. Follow-up consisted of catheter cerebral angiography at 6 and 12 months postembolization. Clopidogrel was discontinued at 6 months and aspirin was reduced to 81 mg daily at 12 months. Occlusion was graded as complete, trace filling, entry remnant, or...

Research paper thumbnail of Utilization of a Novel, Multi-Durometer Intracranial Distal Access Catheter: Nuances and Experience in 110 Consecutive Cases of Aneurysm Flow Diversion

Interventional neurology, 2017

Coaxial catheter support systems provide a safe and stable foundation in endovascular treatment o... more Coaxial catheter support systems provide a safe and stable foundation in endovascular treatment of intracranial aneurysms. Increasingly, robust distal intracranial support is sought during complex neurointerventions. The AXS Catalyst 5 distal access catheter (Cat5) is a new intracranial catheter designed for improved trackability and stability. We report the first experience using Cat5 for aneurysm treatment by flow diversion. A single-center aneurysm database was reviewed for cases of aneurysm treatment with the Pipeline embolization device (PED) that utilized Cat5. Data were collected for patient demographics, aneurysm characteristics, procedural details, catheter positions, vessel tortuosity, and catheter related complications. One hundred and ten cases of aneurysm flow diversion were successfully performed using Cat5. Patient age ranged from 21 to 86 years (mean 57 ± 12.5 years) with 84% women. Aneurysm size ranged from 2 to 28 mm (mean 5.7 ± 5.0 mm), with 97% in the anterior ci...

Research paper thumbnail of Hemorrhage Risk of Brain Arteriovenous Malformations During Pregnancy and Puerperium in a North American Cohort

Stroke, Jun 1, 2017

Conclusions reached in existing literature about risk of arteriovenous malformation (AVM) hemorrh... more Conclusions reached in existing literature about risk of arteriovenous malformation (AVM) hemorrhage during pregnancy are controversial. This study compares the risk of hemorrhage in pregnant and nonpregnant female patients with AVM in a North American cohort. We retrospectively reviewed female patients with AVM evaluated from 1990 to 2015. Exposure period for pregnancy and puerperium was calculated as 40 and 6 weeks, respectively, for each full-term pregnancy and 6 weeks for each abortion. Hemorrhage events and patient-years were calculated during an exposure period (pregnancy and puerperium), and a nonexposure period defined as either the interval from birth until AVM obliteration or until last follow-up after subtracting exposure period. Poisson rate ratio test was used to compare rate of hemorrhage between exposure and nonexposure periods. For 270 female patients with AVM, mean age was 35.0±19.6 years, and race distribution was white (n=165, 61.1%), black (n=59, 21.9%), Hispanic...

Research paper thumbnail of P2Y12 hyporesponse (PRU>200) is not associated with increased thromboembolic complications in anterior circulation Pipeline

Journal of neurointerventional surgery, Jan 6, 2016

Recent reports suggest that thromboembolic complications are associated with Pipeline embolizatio... more Recent reports suggest that thromboembolic complications are associated with Pipeline embolization device (PED) placement cluster in P2Y12 hyporesponders. To evaluate the role of P2Y12 hyporesponse in PED placement by retrospectively reviewing a single-center series of patients. We retrospectively reviewed an institutional review board-approved database of patients with an aneurysm at a single institution and identified all patients with a measured P2Y12 reaction unit (PRU)>200 who had undergone anterior circulation PED placement. Events such as transient ischemic attack, stroke, and hemorrhage were identified as well as demographic and procedural details. Fifty-two patients with a PRU >200 had undergone anterior circulation PED placement. Four patients had prior subarachnoid hemorrhage (SAH) (8%) and 11 aneurysms (21%) had been previously treated. The average aneurysm size was 7.6 mm (±6.2). PED thrombosis occurred intraprocedurally in three patients, none of whom developed n...

Research paper thumbnail of Long-term hemorrhagic risk in pediatric patients with arteriovenous malformations

Journal of Neurosurgery: Pediatrics, 2016

OBJECTIVE Compared with the general population, the specific natural history of arteriovenous mal... more OBJECTIVE Compared with the general population, the specific natural history of arteriovenous malformations (AVMs) in pediatric patients is less well understood. Furthermore, few pediatric studies have compared posttreatment hemorrhagic risk and functional outcome across different treatment modalities. The objective of this study was to elucidate these points. METHODS The authors retrospectively reviewed all pediatric patients with AVMs evaluated at their institution between 1990 and 2013. The AVM natural history was represented by hemorrhagic risk during the observation period. For treated patients, the observation period was defined as the interval between diagnosis and treatment. Posttreatment hemorrhagic risk and functional outcomes were also assessed. RESULTS A total of 124 pediatric patients with AVMs were evaluated, and 90 patients (72.6%) were retained through follow-up. The average patient age was 13.3 ± 3.8 years, with a mean follow-up period of 9.95 years. The overall AVM...

Research paper thumbnail of Lower Risk of Intracranial Arteriovenous Malformation Hemorrhage in Patients With Hereditary Hemorrhagic Telangiectasia

Neurosurgery, 2016

BACKGROUND: Patients diagnosed with hereditary hemorrhagic telangiectasia (HHT) are at risk of de... more BACKGROUND: Patients diagnosed with hereditary hemorrhagic telangiectasia (HHT) are at risk of developing intracranial arteriovenous malformations (AVM). However, the clinical manifestations and natural history of HHT-related AVMs remain unclear due to the rarity of these lesions. OBJECTIVE: To clarify the clinical characteristics and hemorrhagic risk in HHT-related AVMs. METHODS: We performed a retrospective review of all patients diagnosed with both HHT and intracranial AVMs who were evaluated at our institution from 1990 to 2013. Patients with missing data or lost to follow-up were excluded. Baseline characteristics and subsequent hemorrhagic risk were evaluated. RESULTS: In an AVM database of 531 patients with 542 AVMs, a total of 12 HHT patients (2.3%) with 23 AVMs were found. Mean age at diagnosis was 36.5 years, with 41.7% male. Compared to patients with sporadic AVMs, patients with HHT were less likely to present with ruptured AVM (P = .04), headaches (P = .02), and seizures...

Research paper thumbnail of Managing subarachnoid hemorrhage in the neurocritical care unit

Neurosurgery clinics of North America, 2013

Patients with aneurysmal subarachnoid hemorrhage who survive the initial hemorrhage require compl... more Patients with aneurysmal subarachnoid hemorrhage who survive the initial hemorrhage require complex interventions to occlude the aneurysm, typically followed by a prolonged intensive care unit and hospital course to manage the complications that follow. Much of the morbidity and mortality from this disease happens in delayed fashion in the neurocritical care unit. Despite progress made in the last decades, much remains to be understood about this disease and how to best manage these patients. This article provides a review of current evidence and the authors' experience, aimed at providing practical aid to those caring for patients with this disease.

Research paper thumbnail of Cocaine use as an independent predictor of seizures after aneurysmal subarachnoid hemorrhage

Journal of Neurosurgery, 2016

OBJECT Seizures are relatively common after aneurysmal subarachnoid hemorrhage (aSAH). Seizure pr... more OBJECT Seizures are relatively common after aneurysmal subarachnoid hemorrhage (aSAH). Seizure prophylaxis is controversial and is often based on risk stratification; middle cerebral artery (MCA) aneurysms, associated intracerebral hemorrhage (ICH), poor neurological grade, increased clot thickness, and cerebral infarction are considered highest risk for seizures. The purpose of this study was to evaluate the impact of recent cocaine use on seizure incidence following aSAH. METHODS Prospectively collected data from aSAH patients admitted to 2 institutional neuroscience critical care units between 1991 and 2009 were reviewed. The authors analyzed factors that potentially affected the incidence of seizures, including patient demographic characteristics, poor clinical grade (Hunt and Hess Grade IV or V), medical comorbidities, associated ICH, intraventricular hemorrhage (IVH), hydrocephalus, aneurysm location, surgical clipping and cocaine use. They further studied the impact of these ...

Research paper thumbnail of Preoperative Anemia Increases Postoperative Complications and Mortality Following Total Joint Arthroplasty

The Journal of Arthroplasty, 2015

Research paper thumbnail of Cocaine Use Is an Independent Risk Factor for Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

Stroke, 2001

Background and Purpose — Although acute cocaine use has been temporally associated with aneurysma... more Background and Purpose — Although acute cocaine use has been temporally associated with aneurysmal subarachnoid hemorrhage (aSAH), the prevalence of vasospasm and the clinical outcome of patients experiencing aSAH associated with cocaine exposure are unclear. We have analyzed this patient population in our institution to address these issues. Methods — Between 1992 and 1999, 440 patients presented to our institution with aSAH. This sample was retrospectively analyzed to determine which patients had used cocaine within 72 hours of aSAH as documented by urine toxicology studies or patient history. These patients were then compared with control aSAH patients without recent cocaine exposure through univariable and multivariable analyses. Results — Twenty-seven aSAH patients (6.1% of total) had either urine toxicology positive for cocaine metabolites (20 patients, 74%) or a history of cocaine use within 72 hours of aSAH (7 patients, 26%). Cocaine users were more likely to experience cere...

Research paper thumbnail of Risk Factors for Subarachnoid Hemorrhage

Neurosurgery, 2001

OBJECTIVE: Cigarette smoking has been demonstrated to increase the risk of subarachnoid hemorrhag... more OBJECTIVE: Cigarette smoking has been demonstrated to increase the risk of subarachnoid hemorrhage (SAH). Whether cessation of smoking decreases this risk remains unclear. We performed a case-control study to examine the effect of smoking and other known risk factors for cerebrovascular disease on the risk of SAH. METHODS: We reviewed the medical records of all patients with a diagnosis of SAH (n ‫؍‬ 323) admitted to Johns Hopkins Hospital between January 1990 and June 1997. Controls matched for age, sex, and ethnicity (n ‫؍‬ 969) were selected from a nationally representative sample of the Third National Health and Nutrition Examination Survey. We determined the independent association between smoking (current and previous) and various cerebrovascular risk factors and SAH by use of multivariate logistic regression analysis. A separate analysis was performed to determine associated risk factors for aneurysmal SAH. RESULTS: Of 323 patients admitted with SAH (mean age, 52.7 ؎ 14 yr; 93 were men), 173 (54%) were hypertensive, 149 (46%) were currently smoking, and 125 (39%) were previous smokers. In the multivariate analysis, both previous smoking (odds ratio [OR], 4.5; 95% confidence interval [CI], 3.1-6.5) and current smoking (OR, 5.2; 95% CI, 3.6-7.5) were significantly associated with SAH. Hypertension was also significantly associated with SAH (OR, 2.4; 95% CI, 1.8-3.1). The risk factors for 290 patients with aneurysmal SAH were similar and included hypertension (OR, 2.4; 95% CI, 1.8-3.2), previous smoking (OR, 4.1; 95% CI, 2.7-6.0), and current smoking (OR, 5.4; 95% CI, 3.7-7.8). CONCLUSION: Hypertension and cigarette smoking increase the risk for development of SAH, as found in previous studies. However, the increased risk persists even after cessation of cigarette smoking, which suggests the importance of early abstinence from smoking.

Research paper thumbnail of Intraoperative indocyanine green angiography for microsurgical treatment of a craniocervical dural arteriovenous fistula

Clinical Neurology and Neurosurgery, 2012

Spinal dural arteriovenous fistulas (DAVF) may arise anywhere etween foramen magnum and sacrum ac... more Spinal dural arteriovenous fistulas (DAVF) may arise anywhere etween foramen magnum and sacrum accounting for the majority f spinal vascular malformations. Most spinal DAVF are localized t the thoracolumbar junction while DAVF at the craniocervial level are a true exception. The main goal of treatment is the omplete obliteration of the fistula. The use of indocyanine green ICG) videoangiography has been introduced for the treatment of erebrovascular diseases by Raabe and colleagues in 2003 [1]. By ow, it has developed to a technique which has greatly enhanced ntraoperative options of imaging vascular structures like cerebral neurysms. Here we report the case of a patient with DAVF at the craniocerical junction who was referred to our centre after a failed attempt f endovascular embolization at an outside institution. We describe he use of intraoperative ICG angiography to identify the fistula and onfirm its successful obliteration.

Research paper thumbnail of Reprint

Circulation, 2007

Purpose— The aim of this statement is to present current and comprehensive recommendations for th... more Purpose— The aim of this statement is to present current and comprehensive recommendations for the diagnosis and treatment of acute spontaneous intracerebral hemorrhage. Methods— A formal literature search of Medline was performed through the end date of August 2006. The results of this search were complemented by additional articles on related issues known to the writing committee. Data were synthesized with the use of evidence tables. The American Heart Association Stroke Council’s Levels of Evidence grading algorithm was used to grade each recommendation. Prerelease review of the draft guideline was performed by 5 expert peer reviewers and by the members of the Stroke Council Leadership Committee. It is intended that this guideline be fully updated in 3 years’ time. Results— Evidence-based guidelines are presented for the diagnosis of intracerebral hemorrhage, the management of increased arterial blood pressure and intracranial pressure, the treatment of medical complications of ...

Research paper thumbnail of True posterior communicating artery aneurysm

Acta Neurologica Scandinavica, 1991

Research paper thumbnail of Epidemiology and outcomes of pediatric intracranial aneurysms: comparison with an adult population in a 30-year, prospective database

Journal of Neurosurgery: Pediatrics, 2021

OBJECTIVE Pediatric intracranial aneurysms are rare. Most large series in the last 15 years repor... more OBJECTIVE Pediatric intracranial aneurysms are rare. Most large series in the last 15 years reported on an average of only 39 patients. The authors sought to report their institutional experience with pediatric intracranial aneurysms from 1991 to 2021 and to compare pediatric patient and aneurysm characteristics with those of a contemporaneous adult cohort. METHODS Pediatric (≤ 18 years of age) and adult patients with one or more intracranial aneurysms were identified in a prospective database. Standard epidemiological features and outcomes of each pediatric patient were retrospectively recorded. These results were compared with those of adult aneurysm patients managed at a single institution over the same time period. RESULTS From a total of 4500 patients with 5150 intracranial aneurysms admitted over 30 years, there were 47 children with 53 aneurysms and 4453 adults with 5097 aneurysms; 53.2% of children and 36.4% of adults presented with a subarachnoid hemorrhage (SAH). Pediatric...

Research paper thumbnail of 47 Consecutive Cases of Pipeline Flex Flow Diversion Utilizing a Novel Large-Bore Intracranial Intermediate Catheter: Nuances and Institutional Experience with the Syphontrak

Interventional neurology, 2018

The increasing complexity of modern neurointerventions has necessitated a shift in intracranial a... more The increasing complexity of modern neurointerventions has necessitated a shift in intracranial access techniques towards more robust distal support platforms. Here we present our experience with the Syphontrak Support Catheter (Codman Neuro, Raynham, MA, USA) in the triaxial platform for the implantation of the second-generation Pipeline Flex embolization device (PED Flex; Medtronic Neurovascular, Irvine, CA, USA). We retrospectively identified patients who underwent PED Flex treatment utilizing the Syphontrak at a single institution. The procedural data collected included parent artery tortuosity, patient demographics, aneurysm characteristics, other equipment utilized, and catheter-related complications. A total of 47 consecutive aneurysm flow diversions were successfully performed using the Syphontrak. The patients' age ranged from 25 to 80 years (mean 57.3 ± 11.6) and 85% were women. The average aneurysm size was 4.8 ± 2.7 mm (range 2-14). All cases were in the anterior cir...

Research paper thumbnail of Abciximab (ReoPro) Dosing Strategy for the Management of Acute Intraprocedural Thromboembolic Complications during Pipeline Flow Diversion Treatment of Intracranial Aneurysms

Interventional neurology, 2018

Flow diversion with the Pipeline embolization device (PED) is an effective neuro-endovascular met... more Flow diversion with the Pipeline embolization device (PED) is an effective neuro-endovascular method and increasingly accepted for the treatment of cerebral aneurysms. Acute in situ thrombosis is a known complication of PED procedures. There is limited experience in the flow diversion literature on the use of abciximab (ReoPro) for the management of acute thrombus formation in PED cases. Data were collected retrospectively on patients who received intra-arterial (IA) ReoPro with or without subsequent intravenous (IV) infusion during PED flow diversion treatment of intracranial aneurysms. A total of 30 cases in patients with a mean age of 56.7 years (range 36-84) and a mean aneurysm size of 8.6 mm (range 2-25) were identified to have intraprocedural thromboembolic complications during PED treatment. IA ReoPro was administered in all cases, with 20 cases receiving increments of 5-mg boluses and 10 cases receiving a 0.125 mg/kg IA bolus (half cardiac dosing). Complete or partial recana...

Research paper thumbnail of Procedural complexity independent of P2Y12 reaction unit (PRU) values is associated with acute in situ thrombosis in Pipeline flow diversion of cerebral aneurysms

Stroke and vascular neurology, 2018

Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device (PED) pro... more Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device (PED) procedures with potentially high morbidity and mortality. There is controversy regarding the role of platelet function testing with P2Y12 assay as a predictor of intraprocedural thromboembolic events. There is limited knowledge on whether procedural complexity influences these events. Data were collected retrospectively on 742 consecutive PED cases at a single institution. Patients with intraprocedural acute thrombosis were compared with patients without these events. A cohort of 37 PED cases with acute in situ thrombosis (mean age 53.8 years, mean aneurysm size 8.4 mm) was matched with a cohort of 705 PED cases without intraprocedural thromboembolic events (mean age 56.4 years, mean aneurysm size 6.9 mm). All patients with in situ thrombosis received intra-arterial and/or intravenous abciximab. The two groups were evenly matched in patient demographics, previous treatment/subarachnoid hemo...

Research paper thumbnail of Pipeline Embolization for Salvage Treatment of Previously Stented Residual and Recurrent Cerebral Aneurysms

Interventional neurology, 2018

This study assessed the safety and effectiveness of the Pipeline embolization device (PED) for pe... more This study assessed the safety and effectiveness of the Pipeline embolization device (PED) for persistent and recurrent aneurysms previously treated with either a vascular reconstruction device (VRD) or a flow diverter (FD). A prospective, IRB-approved database was analyzed for patients treated with PED for aneurysms previously treated with a stent. Twenty procedures were performed on 18 patients, 11 with prior FD, 7 with VRD, and 2 previously treated with both. Overall, 15 aneurysms were saccular (75%), and size was 13.5 ± 7.6 mm. Location was internal carotid artery (ICA) in 14 cases (70%) and posterior circulation in 6 cases (30%). Average prior treatments were 1.7. Previously FD cases were re-treated at an average of 18.1 months from most recent treatment. Each case used 1 device, 82% with distal coverage and 82% with proximal coverage of prior stent. Balloon remodeling was performed in 3 cases (27%) and no in-stent thrombosis was observed. Previously VRD stent-coiled cases were...

Research paper thumbnail of Pipeline-assisted coil embolization of a large middle cerebral artery pseudoaneurysm in a 9-month-old infant: experience from the youngest flow diversion case

Journal of neurosurgery. Pediatrics, Jan 24, 2018

Intracranial aneurysms in the pediatric population are rare entities. The authors recently treate... more Intracranial aneurysms in the pediatric population are rare entities. The authors recently treated a 9-month-old infant with a 19-mm recurrent, previously ruptured, and coil-embolized left middle cerebral artery (MCA) pseudoaneurysm, which was treated definitively with single-stage Pipeline-assisted coil embolization. The patient was 5 months old when she underwent resection of a left temporal Grade 1 desmoplastic infantile ganglioglioma at an outside institution, which was complicated by left MCA injury with a resultant 9-mm left M pseudoaneurysm. Within a month, the patient had two aneurysmal rupture events and underwent emergency craniectomy for decompression and evacuation of subdural hematoma. The pseudoaneurysm initially underwent coil embolization; however, follow-up MR angiography (MRA) revealed aneurysm recanalization with saccular enlargement to 19 mm. The patient underwent successful flow diversion-assisted coil embolization at 9 months of age. At 7 months after the proce...

Research paper thumbnail of Predictors of cerebral aneurysm persistence and occlusion after flow diversion: a single-institution series of 445 cases with angiographic follow-up

Journal of neurosurgery, Jan 30, 2018

OBJECTIVE Flow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The ... more OBJECTIVE Flow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The existing literature on aneurysm occlusion is limited by heterogeneous follow-up, variable antiplatelet regimens, noninvasive imaging modalities, and nonstandard occlusion assessment. Using a large, single-center cohort with low attrition and standardized antiplatelet tapering, the authors evaluated outcomes after flow diversion of anterior circulation aneurysms to identify predictors of occlusion and aneurysm persistence. METHODS Data from a prospective, IRB-approved database was analyzed for all patients with anterior circulation aneurysms treated by flow diversion with the Pipeline embolization device (PED) at the authors' institution. Follow-up consisted of catheter cerebral angiography at 6 and 12 months postembolization. Clopidogrel was discontinued at 6 months and aspirin was reduced to 81 mg daily at 12 months. Occlusion was graded as complete, trace filling, entry remnant, or...

Research paper thumbnail of Utilization of a Novel, Multi-Durometer Intracranial Distal Access Catheter: Nuances and Experience in 110 Consecutive Cases of Aneurysm Flow Diversion

Interventional neurology, 2017

Coaxial catheter support systems provide a safe and stable foundation in endovascular treatment o... more Coaxial catheter support systems provide a safe and stable foundation in endovascular treatment of intracranial aneurysms. Increasingly, robust distal intracranial support is sought during complex neurointerventions. The AXS Catalyst 5 distal access catheter (Cat5) is a new intracranial catheter designed for improved trackability and stability. We report the first experience using Cat5 for aneurysm treatment by flow diversion. A single-center aneurysm database was reviewed for cases of aneurysm treatment with the Pipeline embolization device (PED) that utilized Cat5. Data were collected for patient demographics, aneurysm characteristics, procedural details, catheter positions, vessel tortuosity, and catheter related complications. One hundred and ten cases of aneurysm flow diversion were successfully performed using Cat5. Patient age ranged from 21 to 86 years (mean 57 ± 12.5 years) with 84% women. Aneurysm size ranged from 2 to 28 mm (mean 5.7 ± 5.0 mm), with 97% in the anterior ci...

Research paper thumbnail of Hemorrhage Risk of Brain Arteriovenous Malformations During Pregnancy and Puerperium in a North American Cohort

Stroke, Jun 1, 2017

Conclusions reached in existing literature about risk of arteriovenous malformation (AVM) hemorrh... more Conclusions reached in existing literature about risk of arteriovenous malformation (AVM) hemorrhage during pregnancy are controversial. This study compares the risk of hemorrhage in pregnant and nonpregnant female patients with AVM in a North American cohort. We retrospectively reviewed female patients with AVM evaluated from 1990 to 2015. Exposure period for pregnancy and puerperium was calculated as 40 and 6 weeks, respectively, for each full-term pregnancy and 6 weeks for each abortion. Hemorrhage events and patient-years were calculated during an exposure period (pregnancy and puerperium), and a nonexposure period defined as either the interval from birth until AVM obliteration or until last follow-up after subtracting exposure period. Poisson rate ratio test was used to compare rate of hemorrhage between exposure and nonexposure periods. For 270 female patients with AVM, mean age was 35.0±19.6 years, and race distribution was white (n=165, 61.1%), black (n=59, 21.9%), Hispanic...

Research paper thumbnail of P2Y12 hyporesponse (PRU>200) is not associated with increased thromboembolic complications in anterior circulation Pipeline

Journal of neurointerventional surgery, Jan 6, 2016

Recent reports suggest that thromboembolic complications are associated with Pipeline embolizatio... more Recent reports suggest that thromboembolic complications are associated with Pipeline embolization device (PED) placement cluster in P2Y12 hyporesponders. To evaluate the role of P2Y12 hyporesponse in PED placement by retrospectively reviewing a single-center series of patients. We retrospectively reviewed an institutional review board-approved database of patients with an aneurysm at a single institution and identified all patients with a measured P2Y12 reaction unit (PRU)>200 who had undergone anterior circulation PED placement. Events such as transient ischemic attack, stroke, and hemorrhage were identified as well as demographic and procedural details. Fifty-two patients with a PRU >200 had undergone anterior circulation PED placement. Four patients had prior subarachnoid hemorrhage (SAH) (8%) and 11 aneurysms (21%) had been previously treated. The average aneurysm size was 7.6 mm (±6.2). PED thrombosis occurred intraprocedurally in three patients, none of whom developed n...

Research paper thumbnail of Long-term hemorrhagic risk in pediatric patients with arteriovenous malformations

Journal of Neurosurgery: Pediatrics, 2016

OBJECTIVE Compared with the general population, the specific natural history of arteriovenous mal... more OBJECTIVE Compared with the general population, the specific natural history of arteriovenous malformations (AVMs) in pediatric patients is less well understood. Furthermore, few pediatric studies have compared posttreatment hemorrhagic risk and functional outcome across different treatment modalities. The objective of this study was to elucidate these points. METHODS The authors retrospectively reviewed all pediatric patients with AVMs evaluated at their institution between 1990 and 2013. The AVM natural history was represented by hemorrhagic risk during the observation period. For treated patients, the observation period was defined as the interval between diagnosis and treatment. Posttreatment hemorrhagic risk and functional outcomes were also assessed. RESULTS A total of 124 pediatric patients with AVMs were evaluated, and 90 patients (72.6%) were retained through follow-up. The average patient age was 13.3 ± 3.8 years, with a mean follow-up period of 9.95 years. The overall AVM...

Research paper thumbnail of Lower Risk of Intracranial Arteriovenous Malformation Hemorrhage in Patients With Hereditary Hemorrhagic Telangiectasia

Neurosurgery, 2016

BACKGROUND: Patients diagnosed with hereditary hemorrhagic telangiectasia (HHT) are at risk of de... more BACKGROUND: Patients diagnosed with hereditary hemorrhagic telangiectasia (HHT) are at risk of developing intracranial arteriovenous malformations (AVM). However, the clinical manifestations and natural history of HHT-related AVMs remain unclear due to the rarity of these lesions. OBJECTIVE: To clarify the clinical characteristics and hemorrhagic risk in HHT-related AVMs. METHODS: We performed a retrospective review of all patients diagnosed with both HHT and intracranial AVMs who were evaluated at our institution from 1990 to 2013. Patients with missing data or lost to follow-up were excluded. Baseline characteristics and subsequent hemorrhagic risk were evaluated. RESULTS: In an AVM database of 531 patients with 542 AVMs, a total of 12 HHT patients (2.3%) with 23 AVMs were found. Mean age at diagnosis was 36.5 years, with 41.7% male. Compared to patients with sporadic AVMs, patients with HHT were less likely to present with ruptured AVM (P = .04), headaches (P = .02), and seizures...

Research paper thumbnail of Managing subarachnoid hemorrhage in the neurocritical care unit

Neurosurgery clinics of North America, 2013

Patients with aneurysmal subarachnoid hemorrhage who survive the initial hemorrhage require compl... more Patients with aneurysmal subarachnoid hemorrhage who survive the initial hemorrhage require complex interventions to occlude the aneurysm, typically followed by a prolonged intensive care unit and hospital course to manage the complications that follow. Much of the morbidity and mortality from this disease happens in delayed fashion in the neurocritical care unit. Despite progress made in the last decades, much remains to be understood about this disease and how to best manage these patients. This article provides a review of current evidence and the authors' experience, aimed at providing practical aid to those caring for patients with this disease.