C F Dowd

University of California, San Francisco, San Francisco, California, United States

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Publications (119)429.16 Total impact

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    ABSTRACT: Intracranial atherosclerotic disease (ICAD) is often stratified by degree of stenosis. Additional features such as patient demographics and symptom characteristics also affect lesion behavior and response to treatment. This study compares stratification by degree of narrowing to these additional features.
    Journal of Neurointerventional Surgery 07/2014; 6 Suppl 1:A7. · 2.50 Impact Factor
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    ABSTRACT: Although many intracranial dural arteriovenous fistulas (DAVFs) are straightforward to treat, de novo and rapidly progressive ("runaway" or "malignant") DAVFs are more complex, often requiring multiple treatment sessions with suboptimal results. As these are rare entities, we sought to review our experience in the treatment of de novo and progressive DAVFs in order to better understand predictors of disease progression.
    Journal of Neurointerventional Surgery 07/2014; 6 Suppl 1:A47. · 2.50 Impact Factor
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    ABSTRACT: Different types of symptomatic intracranial stenosis may respond differently to interventional therapy. We investigated symptomatic and pathophysiologic factors that may influence clinical outcomes of patients with intracranial atherosclerotic disease who were treated with stents. A retrospective analysis was performed of patients treated with stents for intracranial atherosclerosis at 4 centers. Patient demographics and comorbidities, lesion features, treatment features, and preprocedural and postprocedural functional status were noted. χ(2) univariate and multivariate logistic regression analysis was performed to assess technical results and clinical outcomes. One hundred forty-two lesions in 131 patients were analyzed. Lesions causing hypoperfusion ischemic symptoms were associated with fewer strokes by last contact [χ(2) (1, n = 63) = 5.41, P = .019]. Nonhypoperfusion lesions causing symptoms during the 14 days before treatment had more strokes by last contact [χ(2) (1, n = 136), 4.21, P = .047]. Patients treated with stents designed for intracranial deployment were more likely to have had a stroke by last contact (OR, 4.63; P = .032), and patients treated with percutaneous balloon angioplasty in addition to deployment of a self-expanding stent were less likely to be stroke free at point of last contact (OR, 0.60; P = .034). More favorable outcomes may occur after stent placement for lesions causing hypoperfusion symptoms and when delaying stent placement 7-14 days after most recent symptoms for lesions suspected to cause embolic disease or perforator ischemia. Angioplasty performed in addition to self-expanding stent deployment may lead to worse outcomes, as may use of self-expanding stents rather than balloon-mounted stents.
    American Journal of Neuroradiology 03/2014; · 3.17 Impact Factor
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    ABSTRACT: The imaging characteristics and modes of presentation of brain AVMs may vary with patient age. Our aim was to determine whether clinical and angioarchitectural features of brain AVMs differ between children and adults. A prospectively collected institutional data base of all patients diagnosed with brain AVMs since 2001 was queried. Demographic, clinical, and angioarchitecture information was summarized and analyzed with univariable and multivariable models. Results often differed when age was treated as a continuous variable as opposed to dividing subjects into children (18 years or younger; n = 203) versus adults (older than 18 years; n = 630). Children were more likely to present with AVM hemorrhage than adults (59% versus 41%, P < .001). Although AVMs with a larger nidus presented at younger ages (mean of 26.8 years for >6 cm compared with 37.1 years for <3 cm), this feature was not significantly different between children and adults (P = .069). Exclusively deep venous drainage was more common in younger subjects when age was treated continuously (P = .04) or dichotomized (P < .001). Venous ectasia was more common with increasing age (mean, 39.4 years with ectasia compared with 31.1 years without ectasia) and when adults were compared with children (52% versus 35%, P < .001). Patients with feeding artery aneurysms presented at a later average age (44.1 years) than those without such aneurysms (31.6 years); this observation persisted when comparing children with adults (13% versus 29%, P < .001). Although children with brain AVMs were more likely to come to clinical attention due to hemorrhage than adults, venous ectasia and feeding artery aneurysms were under-represented in children, suggesting that these particular high-risk features take time to develop.
    American Journal of Neuroradiology 03/2014; · 3.17 Impact Factor
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    ABSTRACT: The ability of polymer-modified coils to promote stable aneurysm occlusion after endovascular treatment is not well-documented. Angiographic aneurysm recurrence is widely used as a surrogate for treatment failure, but studies documenting the correlation of angiographic recurrence with clinical failure are limited. This trial compares the effectiveness of Matrix(2) polyglycolic/polylactic acid biopolymer-modified coils with bare metal coils and correlates the angiographic findings with clinical failure (ie, target aneurysm recurrence), a composite end point that includes any incident of posttreatment aneurysm rupture, retreatment, or unexplained death. This was a multicenter randomized noninferiority trial with blinded end point adjudication. We enrolled 626 patients, divided between Matrix(2) and bare metal coil groups. The primary outcome was target aneurysm recurrence at 12 ± 3 months. At 455 days, at least 1 target aneurysm recurrence event had occurred in 14.6% of patients treated with bare metal coils and 13.3% of Matrix(2) (P = .76, log-rank test) patients; 92.8% of target aneurysm recurrence events were re-interventions for aneurysms that had not bled after treatment, and 5.8% of target aneurysm recurrence events resulted from hemorrhage or rehemorrhage, with or without retreatment. Symptomatic re-intervention occurred in only 4 (0.6%) patients. At 455 days, 95.8% of patients with unruptured aneurysms and 90.4% of those with ruptured aneurysms were independent (mRS ≤ 2). Target aneurysm recurrence was associated with incomplete initial angiographic aneurysm obliteration, presentation with rupture, and a larger aneurysmal dome and neck size. Tested Matrix(2) coils were not inferior to bare metal coils. Endovascular coiling of intracranial aneurysms was safe, and the rate of technical success was high. Target aneurysm recurrence is a promising clinical outcome measure that correlates well with established angiographic measurements.
    American Journal of Neuroradiology 01/2014; · 3.17 Impact Factor
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    ABSTRACT: BACKGROUND AND PURPOSE:Stent-assisted coiling may result in less aneurysm recanalization but more complications than coiling alone. We evaluated outcomes of coiling with and without stents in the multicenter Matrix and Platinum Science Trial.MATERIALS AND METHODS:All patients in the Matrix and Platinum Science Trial with unruptured intracranial aneurysms treated per protocol were included. Baseline patient and aneurysm characteristics, procedural details, neurologic outcomes, angiographic outcomes, and safety data were analyzed.RESULTS:Overall, 137 of 361 (38%) patients were treated with a stent. Stent-coiled aneurysms had wider necks (≥4 mm in 62% with stents versus 33% without, P < .0001) and lower dome-to-neck ratios (1.3 versus 1.8, P < .0001). Periprocedural serious adverse events occurred infrequently in those treated with and without stents (6.6% versus 4.5%, P = .39). At 1 year, total significant adverse events, mortality, and worsening of mRS were similar in treatment groups, but ischemic strokes were more common in stent-coiled patients than in coiled patients (8.8% versus 2.2%, P = .005). However, multivariate analysis confirmed that at 2 years after treatment, prior cerebrovascular accident (OR, 4.7; P = .0089) and aneurysm neck width ≥4 mm (OR, 4.5; P = .02) were the only independent predictors of ischemic stroke. Stent use was not an independent predictor of ischemic stroke at 2 years (OR, 1.1; P = .94). Stent use did not predict target aneurysm recurrence at 2 years, but aneurysm dome size ≥10 mm (OR, 9.94; P < .0001) did predict target aneurysm recurrence.CONCLUSIONS:Stent-coiling had similar outcomes as coiling despite stented aneurysms having more difficult morphology than coiled aneurysms. Increased ischemic events in stent-coiled aneurysms were attributable to baseline risk factors and aneurysm morphology.
    American Journal of Neuroradiology 11/2013; · 3.17 Impact Factor
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    ABSTRACT: NGAVFs are rare vascular malformations usually presenting in infancy or childhood. We sought to identify clinical and angiographic predictors of clinical outcome for these lesions. Retrospective review of a neurointerventional data base identified 386 pediatric patients with intracranial AVFs and AVMs, from which a cohort of 25 patients with NGAVF were selected for medical record and imaging analysis. NGAVFs constituted 7.3% of pediatric intracranial vascular lesions with a nondural arteriovenous shunt. Seven of 8 patients who presented in the first month of life had CHF and harbored large, complex fistulas with multiple sites of arteriovenous shunting. Single-hole fistulas predominated later in childhood and more frequently presented with seizures, hemorrhage, or focal neurologic deficits. More treatment procedures were performed in subjects presenting at ≤2 years of age compared with older children (median = 3 versus 2, P = .041), and in those harboring a multi-hole fistula versus those with a single-hole fistula (median = 3 versus 2, P = .003). Eighteen patients (72%) had complete posttreatment elimination of NGAVF shunting. Compared with patients presenting at >2 years of age, patients presenting in the first 2 years of life were more likely to have a multi-hole fistula (100% versus 25%, P = .0001) and to have a poor clinical outcome (54% versus 0%, P = .0052), defined as a pediatric mRS of ≥3. The morbidity of NGAVF appears higher than previously reported despite a somewhat higher rate of angiographic cure. Poor clinical outcome occurred primarily in patients with multi-hole NGAVFs presenting at ≤2 years of age.
    American Journal of Neuroradiology 07/2012; 33(9):1710-9. · 3.17 Impact Factor
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    ABSTRACT: Children with brain aneurysms may be at higher risk than adults to develop new or enlarging aneurysms in a relatively short time. We sought to identify comorbidities and angiographic features in children that predict new aneurysm formation or enlargement of untreated aneurysms. Retrospective analysis of the University of California-San Francisco Pediatric Aneurysm Cohort data base including medical records and imaging studies was performed. Of 83 patients harboring 114 intracranial aneurysms not associated with brain arteriovenous malformations or intracranial arteriovenous fistulas, 9 (8.4%) developed new or enlarging brain aneurysms an average of 4.2 years after initial presentation. Comorbidities that may be related to aneurysm formation were significantly higher in patients who developed new aneurysms (89%) as opposed to patients who did not develop new or enlarging aneurysms (41%; RR, 9.5; 95% CI, 1.9%-48%; P = .0099). Patients with multiple aneurysms at initial presentation were more likely than patients with a single aneurysm at presentation to develop a new or enlarging aneurysm (RR, 6.2; 95% CI, 2.1%-185; P = .0058). Patients who initially presented with at least 1 fusiform aneurysm were more likely to develop a new or enlarging aneurysm than patients who did not present with a fusiform aneurysm (RR, 22; 95% CI, 3.6%-68%; P = .00050). Index aneurysm treatment with parent artery occlusion also was associated with higher risk of new aneurysm formation (RR, 4.2; 95% CI, 1.3%-13%; P = .024). New aneurysms did not necessarily arise near index aneurysms. The only fatality in the series was due to subarachnoid hemorrhage from a new posterior circulation aneurysm arising 20 months after index anterior circulation aneurysm treatment in an immunosuppressed patient. Patients who presented with a fusiform aneurysm had a significantly greater incidence of developing a new aneurysm or enlargement of an index aneurysm than did those who presented with a saccular aneurysm. In our patient cohort, 8 of the 9 children who eventually developed new or enlarging brain aneurysms initially presented with fusiform aneurysm morphology. Other comorbidities or multiple aneurysms were also common in these patients at initial presentation.
    American Journal of Neuroradiology 11/2011; 32(11):2017-22. · 3.17 Impact Factor
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    ABSTRACT: PurposeMeningiomas often benefit from preoperative embolization in order to reduce operative blood loss and associated morbidity. Intraarterial (IA) administration of contrast directly into the external carotid artery (ECA) and internal carotid artery (ICA) branches supplying the tumor during the embolization procedure maps out the blood vessels supplying the tumor as well as evaluating which portions of the tumor are successfully devascularized prior to surgery. Whereas IA digital subtraction x-ray angiography (DSA) is the gold standard for embolization guidance, IA perfusion MRI may offer increased sensitivity to residual areas of vascularized tumor.Materials and Methods Studies were performed in a combined “XMR” suite wherein an x-ray angiography unit (Integris V5000, Philips Medical Systems) is coupled in-line to a 1.5 T MR scanner (Intera, Philips Medical Systems), allowing easy patient movement between the two imaging modalities during endovascular procedures. We evaluated 14 patients with selective IA T2* dynamic susceptibility contrast (DSC) perfusion MR during preoperative embolization. Eight of these patients were also evaluated with intraprocedural IA T1 weighted perfusion MR. IA perfusion was performed with dilute Gd injected initially into the external carotid and subsequently into the common carotid. The selected carotid artery was confirmed to be providing vascular supply to the tumor by prior angiographic evaluation. The portion of the tumor demonstrated to be associated with external or internal carotid supply, based on IA MR perfusion measures, were correlated with DSA obtained during each procedure. IA perfusion assessments were additionally compared to preoperative conventional MRI and IV T2* perfusion MR studies.ResultsBoth T2* and T1 IA perfusion MR techniques were more sensitive than DSA at detecting vascularized tumor prior to or following embolization. The T1 technique was subject to less susceptibility artifact, and thus performed better than the T2* technique at the skull base and near aerated paranasal sinuses. Both IA MR perfusion techniques demonstrated tighter arterial input functions than the IV MRI perfusion technique due to contrast administration directly into cervicocerebral arteries. Similarly, time enhancement curves for the IA MR perfusion methods demonstrated reduced mean transit time and lack of a recirculation peak as comparted to the IV MR perfusion method. IA MR perfusion methods were good at differentiating ECA from ICA supply to individual tumors. However, vascular variants such as anterior falx artery or ethmoidal artery tumor supply arising from the ophthalmic artery (ICA branches outside the blood brain barrier) presented interpretive challenges for MRI but were readily apparent on DSA.ConclusionIA MR perfusion techniques appear to be a useful adjunct to DSA in determining tumor vascularity and the source of that blood supply during DSA guided preoperative embolization procedures.
    Journal of Neurointerventional Surgery 07/2011; 3(1). · 2.50 Impact Factor
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    ABSTRACT: A 7-year-old girl with a history of headaches and Gorham disease was surgically treated in infancy for Chiari I malformation. Subsequent investigation revealed that her cerebellar tonsillar ectopia was due to a long-standing spinal CSF-lymphatic fistula causing intracranial hypotension. Percutaneous fistula closure was performed several times, resulting in transient symptomatic improvement.
    American Journal of Neuroradiology 06/2011; 32(11):E198-200. · 3.17 Impact Factor
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    ABSTRACT: CV following aneurysmal SAH is a significant cause of morbidity and mortality. We review our experiences using PTA and IA verapamil infusion for treating medically refractory cases. We performed a retrospective review of patients with SAH admitted from July 2003 to January 2008. Of 546 patients admitted within 72 hours of symptom onset, 231 patients (42%) developed symptomatic CV and 189 patients (35%) required endovascular therapy. A total of 346 endovascular sessions were performed consisting of 1 single angioplasty, 286 IA verapamil infusions, and 59 combined treatments. PTA was performed on 151 vessel segments, and IA verapamil was infused in 720 vessel segments. IA verapamil doses ranged from 2.0 to 30.0 mg per vessel segment and from 3.0 to 55.0 mg per treatment session. Repeat treatments were necessary in 102 patients (54%) for persistent, recurrent, or worsening CV. There were 6 treatment-related complications, of which 2 resulted in clinical worsening. No deaths were attributable to endovascular therapy. At follow-up, 115 patients (61%) had a good outcome and 55 patients (29%) had a poor outcome. Sixteen patients died from causes related to SAH, while 3 died from other medical complications. Endovascular treatments are an integral part of managing patients with medically refractory CV. In our experience, PTA and IA verapamil are safe, with a low complication rate, but further studies are required to determine appropriate patient selection and treatment efficacy.
    American Journal of Neuroradiology 11/2010; 31(10):1911-6. · 3.17 Impact Factor
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    ABSTRACT: The natural history of PMAVFs, also known as type IV spinal cord AVFs, is incompletely understood. Both open surgical and endovascular approaches have been described as treatment modalities for this disease. The goal of this study was to evaluate the long-term outcome of patients with PMAVFs treated at a single tertiary care institution. We conducted a retrospective study of 32 patients with PMAVFs, evaluated between 1983 and 2009. Data were gathered by reviewing outpatient clinic notes, operative and radiologic reports, and spinal angiograms. The PMAVFs were categorized into 1 of 3 types based on the angiographic imaging criteria. Pretreatment and posttreatment ambulation and micturition symptoms were quantified by using the ALS. Thirty patients underwent corrective procedures, 4 by embolization alone, 11 by surgery alone, and 15 with a combination of the 2. Twenty-eight patients underwent follow-up spinal angiography, with residual shunt noted in 6 patients. The mean follow-up period was 54 months (range, 1-228 months). Analysis of the ALS scores revealed that treatment of PMAVFs, independent of technique, resulted in significant improvement in ambulation but inconsistent changes in micturition. In addition, residual fistula at the time of the follow-up angiogram was associated with worsened neurologic status or lack of improvement. Outcome analysis based on fistula type showed dramatic improvement in ALS ambulation scores (62%) for type 3 fistulas, compared with types 1 and 2 (26% and 27%, respectively). Significant improvement in ambulation but in not micturition was observed following treatment. Residual fistula on follow-up angiography was associated with progressive worsening or lack of improvement in neurologic function. Patients with type 3 fistulas were shown to benefit most from treatment, with marked improvement in posttreatment ambulation scores. As endovascular and surgical techniques continue to evolve, further studies are warranted.
    American Journal of Neuroradiology 11/2010; 31(10):1824-30. · 3.17 Impact Factor
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    ABSTRACT: Cerebral and cervical arterial abnormalities are the most common non-cutaneous anomaly in PHACE syndrome, but the location and type of arterial lesions that occur have not been systematically assessed in a large cohort. Our aim was to characterize the phenotypic spectrum of arteriopathy, assess the frequency with which different arteries are involved, and evaluate spatial relationships between arteriopathy, brain structural lesions, and hemangiomas in PHACE syndrome. Intracranial MRA and/or CTA images from 70 children and accompanying brain MR images in 59 patients with arteriopathy and PHACE syndrome were reviewed to identify the type and location of arterial lesions and brain abnormalities. Five categories of arteriopathy were identified and used for classification: dysgenesis, narrowing, nonvisualization, primitive embryonic carotid-vertebrobasilar connections, and anomalous arterial course or origin. Univariate logistic regression analyses were performed to test for associations between arteriopathy location, hemangiomas, and brain abnormalities. By study design, all patients had arterial abnormalities, and 57% had >1 form of arteriopathy. Dysgenesis was the most common abnormality (56%), followed by anomalous course and/or origin (47%), narrowing (39%), and nonvisualization (20%). Primitive embryonic carotid-vertebrobasilar connections were present in 20% of children. Hemangiomas were ipsilateral to arteriopathy in all but 1 case. The frontotemporal and/or mandibular facial segments were involved in 97% of cases, but no other specific associations between arteriopathy location and hemangioma sites were detected. All cases with posterior fossa anomalies had either ICA anomalies or persistent embryonic carotid-basilar connections. The arteriopathy of PHACE syndrome commonly involves the ICA and its embryonic branches, ipsilateral to the cutaneous hemangioma, with dysgenesis and abnormal arterial course the most commonly noted abnormalities. Brain abnormalities are also typically ipsilateral.
    American Journal of Neuroradiology 11/2010; 31(10):1980-6. · 3.17 Impact Factor
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    ABSTRACT: A comprehensive evaluation of aneurysmal morphometry requires appreciation of both the vascular lumen and the intraluminal thrombus. MR imaging methods can both evaluate the lumen and directly image the vessel wall. We investigated the ability of T1-weighted, T2-weighted, and steady-state MR imaging techniques to delineate thrombus morphology and reveal changes with time. Nine patients with fusiform basilar or intracranial vertebral artery aneurysms that contained intraluminal thrombus were studied with MR imaging. All patients underwent at least 2 imaging sessions, which were separated by 4-22 months. Analysis of signal intensity to determine the mean signal intensity from thrombus, blood, CSF, and brain in matched regions was performed. Aneurysm maximal diameter and cross-sectional area were determined with and without thrombus. Thrombus was identified on all image sequences, and its general appearance was consistent between imaging sessions. Thrombus produced the highest and most consistent signal intensities with T1-weighted and steady-state techniques, though the latter showed superior contrast between luminal blood and thrombus. Heterogeneity within clot was evident in 4/9 of patients, with peripheral hyperintensity being a common feature. Steady-state imaging was found to be superior to T1- and T2-weighted imaging for delineating and characterizing intraluminal thrombus within aneurysms. The imaging characteristics of intraluminal thrombus proved to be very consistent for long periods. Assessment of overall aneurysm size, including thrombosed portions, permits more accurate evaluation of aneurysm growth and concomitantly may permit more informed clinical decision-making with regard to the timing and need for aneurysm treatment.
    American Journal of Neuroradiology 11/2010; 32(2):346-51. · 3.17 Impact Factor
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    ABSTRACT: A neonate with congestive heart failure at birth due to a nearly holohemispheric pial arteriovenous malformation is described. This occurred despite a normal second trimester prenatal sonogram. Successful treatment of heart failure was achieved by embolization alone. This case demonstrates that hemodynamically significant lesions may arise later or enlarge more rapidly in utero than previously thought.
    Journal of Neurointerventional Surgery 12/2009; 1(2):151-3. · 2.50 Impact Factor
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    ABSTRACT: Pediatric aneurysms are rare and, thus, relatively poorly understood as compared to those in adults. Our aim was to characterize the clinical, imaging, treatment, and outcome data of patients younger than 19 years diagnosed with intracranial aneurysms at a tertiary care institution. We performed a retrospective medical record review of pediatric patients examined at our university hospital between 1981 and 2008. We evaluated 77 patients (mean age, 12 years; 40 female, 37 male) with 103 intracranial aneurysms. Patients presented with headache (45%), cranial neuropathies (16%), nausea/vomiting (15%), vision changes (13%), trauma (13%), seizure (4%), or sensory changes (3%). Subarachnoid hemorrhage occurred in 25 patients. Thirty-one fusiform aneurysms occurred in 25 patients. Forty-seven saccular aneurysms occurred in 35 patients. Twelve infectious aneurysms occurred in 6 patients. Fifteen traumatic aneurysms occurred in 12 patients. Fifty-nine patients underwent treatment of their aneurysms; 18 patients' conditions were managed conservatively. Nineteen patients underwent primary endovascular coiling, 1 patient had endovascular stent-assisted coiling, 11 patients underwent endovascular parent artery occlusion, 19 patients underwent surgical clipping, and 10 patients had aneurysms trapped and bypassed. Mortality was 1.3%. Morbidity included 8% infarction and 4% new-onset seizures. Six patients developed new aneurysms or had enlargement of untreated aneurysms. In our experience, intracranial aneurysms of childhood show a female predilection and predominantly saccular morphology. In neurovascular centers where microneurosurgical and endovascular options are available, most children with intracranial aneurysms can be successfully treated with low morbidity and mortality. Fusiform aneurysms require a combined microneurosurgical and endovascular approach more often than saccular aneurysms. The development of new aneurysms in pediatric patients during limited follow-up warrants further investigation.
    American Journal of Neuroradiology 05/2009; 30(7):1315-24. · 3.17 Impact Factor
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    ABSTRACT: Embolization of meningiomas has emerged as a preoperative adjuvant therapy that has proved effective in mitigating blood loss during surgical resection. Arterial supply to these tumors is typically identified by diffuse areas of parenchymal staining after selective x-ray angiograms. We investigate the benefits that selective injection of MR contrast may have in identifying vascular territories and determining the effects of embolization therapy. Selective intra-arterial (IA) injection of dilute MR contrast media was used to assess the vascular distribution territories of meningeal tumors before and after embolization therapy. Regions of the tumor that experienced loss of signal intensity after localized contrast injections into the external and common carotid as well as vertebral arteries were used to quantify the specific vessel's volume of distribution. Assessments were made before and after embolization to reveal changes in the vascular supply of the tumor. MR findings were compared with radiographic evaluation of tumor vascular supply on the basis of conventional x-ray angiography. MR proved to be an excellent means to assess tissue fed by selected arteries and clearly demonstrated the treated and untreated portions of the neoplasm after therapy. In some instances, MR revealed postembolization residual enhancement of the tumor that was difficult to appreciate on x-ray angiograms. Very low contrast dose was necessary, which made repeated assessment during therapy practical. MR perfusion imaging with selective IA injection of dilute contrast can reveal the distribution territory of vessels. Changes in tumor vasculature could be detected after embolization, which reveal the volumetric fraction of the tumor affected by the therapy.
    American Journal of Neuroradiology 11/2007; 28(9):1771-7. · 3.68 Impact Factor
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    ABSTRACT: We report 3 patients with previously undiagnosed spinal dural arteriovenous fistulas (SDAVFs), who developed acute paraparesis following lumbar epidural steroid injection. MR imaging demonstrated spinal cord T2 hyperintensity, edema and/or enhancement of the conus, and intradural enlarged vascular flow voids. Spinal angiography confirmed SDAVFs arising from pedicles remote from the sites of the epidural steroid injection. Fistulas were eliminated with either endovascular or combination endovascular and open surgical approaches, with subsequent partial resolution of paraparesis.
    American Journal of Neuroradiology 04/2007; 28(3):581-3. · 3.68 Impact Factor
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    ABSTRACT: Eighteen patients underwent stenting for symptomatic basilar artery stenosis. There were three major periprocedural complications (16.7%) without fatality. At a mean 26.7 +/- 12.1-month follow-up, 15 patients (83.3%) had an excellent long-term outcome. Only one patient (5.6%) had moderate disability from recurrent stroke, and two patients died of medical illness at 30 and 36 months after stenting. In this uncontrolled study, stenting appeared to be effective in reducing stroke risk and death and worthy of further scrupulous trial.
    Neurology 04/2005; 64(6):1055-7. · 8.30 Impact Factor
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    ABSTRACT: To assess neurodevelopmental outcome after endovascular treatment of vein of Galen malformations (VOGM). Outcome of patients who underwent endovascular treatment for VOGM between 1983 and 2002 was assessed by chart review and parental questionnaires. Development was classified as normal, minor delay (slow initial acquisition of milestones but no permanent disability), or significant delay (slow or incomplete acquisition of milestones with some permanent disability) using an adaptation of the Denver Developmental Questionnaire. Twenty-seven patients were identified: five presented prenatally (by ultrasound), 16 as neonates, and 6 after the neonatal period. The most common presenting features were congestive heart failure (CHF; 16/27) and hydrocephalus (8/27). The 16 patients with CHF all presented either prenatally or neonatally; 4 died acutely, 6 had significant delay, and 6 had no or minor developmental delay. Of those presenting in the perinatal period without CHF, all survived, two of five were significantly delayed, and three of five had no delay. Of those presenting after the neonatal period, all survived and only one of six had delay. By angiographic classification, outcome was worse for those with choroidal VOGM (3/13 died; 5/13 had significant delay) than for those with mural VOGM (2/10 had significant delay; none died). For the entire series, 52% of all cases (61% of survivors) had no or minor delay. Fourteen of 27 children who received treatment for VOGM had a favorable outcome. Features associated with worse outcome were perinatal presentation, presence of CHF, and choroidal angioarchitecture.
    Neurology 12/2003; 61(10):1386-90. · 8.30 Impact Factor

Publication Stats

4k Citations
429.16 Total Impact Points

Institutions

  • 1989–2014
    • University of California, San Francisco
      • • Department of Radiology and Biomedical Imaging
      • • Department of Neurology
      • • Division of Hospital Medicine
      San Francisco, California, United States
  • 1991–2009
    • San Francisco VA Medical Center
      San Francisco, California, United States
  • 2000
    • Royal Perth Hospital
      Perth City, Western Australia, Australia
  • 1996
    • Wakayama Medical University
      Wakayama, Wakayama, Japan