300 Longwood Ave Children's Hospital Boston - Neuroradiology
Boston MA 02115
Medical School: Cornell University Medical College - 1998
Accepts Medicare: No
Participates In eRX: No
Participates In PQRS: No
Participates In EHR: No
License #: 227754
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Dr. Darren Orbach is associated with these group practices
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Mechanical thrombectomy for pediatric acute ischemic stroke: review of the literature. - Journal of neurointerventional surgery
Given recent strongly positive randomized controlled adult mechanical thrombectomy trials, we sought to perform a comprehensive review of available literature on IA pediatric stroke intervention, with a focus on modern mechanical devices.PubMed search for pediatric patients undergoing IA treatment of acute ischemic stroke (AIS) using modern devices between 2008 and 2015. 29 patients were included in this analysis.Average age was 10.3â€…years, 74.1% male, middle cerebral and basilar arteries represented 89.6% of 36 occluded vessels, and average pediatric stroke scale score of 18.1. Average time from symptom onset to intervention was 8.8â€…hours and 13.8% of patients received IV tissue plasminogen activator prior to mechanical thrombectomy. Stent retrievers were used in 58.6% of cases, the Penumbra system in 34.5%, and the Merci device in 27.6%. Modified Thrombolysis In Cerebral Infarction 2b/3 recanalization was achieved in 75.9% of cases. There were no major adverse events related to the intervention, although one procedure was associated with device malfunction without a definite change in long-term outcome. The average modified Rankin Scale (mRS) score was <1 (0.86) at the longest available follow-up period, based on clinical description or provided mRS score.This study suggests that mechanical thrombectomy in pediatric patients presenting with high pediatric NIH Stroke Scale scores and proximal large vessel occlusion is associated with high recanalization rates and excellent clinical outcome, although this is a retrospective review and the sample size is too small to make any definitive conclusions. This study provides class IVC evidence that endovascular treatment of pediatric AIS increases the chance of a good clinical outcome.Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Considerations in Applying a New Stent Retriever in Pediatric Endovascular Cerebral Thrombectomy for Acute Ischemic Stroke. - Pediatric neurosurgery
Acute ischemic stroke (AIS) in children has been difficult to diagnose, treat and study, due to atypical clinical presentation, imaging challenges and the rarity of large-vessel embolic occlusion as the etiology of acute neurological change in children. With endovascular thrombectomy showing success in randomized trials of adult AIS, the technique is increasingly being extrapolated to pediatric stroke. However, there is little evidence regarding the safety or efficacy of applying in children these devices developed and tested in adults. There is concern about a vessel-to-device size mismatch that may result in a different complication and benefit profile than typically seen. We report on the successful application in pediatric stroke of a newer-generation, smaller stent retriever, designed to be delivered through relatively smaller and more navigable microcatheters than the prior generation of this device.Â© 2016 S. Karger AG, Basel.
Direct neural current imaging in an intact cerebellum with magnetic resonance imaging. - NeuroImage
The ability to detect neuronal currents with high spatiotemporal resolution using magnetic resonance imaging (MRI) is important for studying human brain function in both health and disease. While significant progress has been made, we still lack evidence showing that it is possible to measure an MR signal time-locked to neuronal currents with a temporal waveform matching concurrently recorded local field potentials (LFPs). Also lacking is evidence that such MR data can be used to image current distribution in active tissue. Since these two results are lacking even in vitro, we obtained these data in an intact isolated whole cerebellum of turtle during slow neuronal activity mediated by metabotropic glutamate receptors using a gradient-echo EPI sequence (TR=100ms) at 4.7T. Our results show that it is possible (1) to reliably detect an MR phase shift time course matching that of the concurrently measured LFP evoked by stimulation of a cerebellar peduncle, (2) to detect the signal in single voxels of 0.1mm(3), (3) to determine the spatial phase map matching the magnetic field distribution predicted by the LFP map, (4) to estimate the distribution of neuronal current in the active tissue from a group-average phase map, and (5) to provide a quantitatively accurate theoretical account of the measured phase shifts. The peak values of the detected MR phase shifts were 0.27-0.37Â°, corresponding to local magnetic field changes of 0.67-0.93nT (for TE=26ms). Our work provides an empirical basis for future extensions to in vivo imaging of neuronal currents.Copyright Â© 2016 Elsevier Inc. All rights reserved.
The natural history of cerebral cavernous malformations in children. - Journal of neurosurgery. Pediatrics
OBJECT Cerebral cavernous malformations (CMs) are a source of neurological morbidity from seizures and focal neurological deficits due to mass effect and hemorrhage. Although several natural history reports exist for adults with CMs, similar data for pediatric patients are limited. METHODS The authors reviewed hospital databases to identify children with CMs who had not been treated surgically and who had clinical and radiological follow-up. Annual hemorrhage rates were calculated in lesion-years, and risk factors were assessed using the Cox proportional hazards model. RESULTS In a cohort of 167 patients with 222 CMs, the mean patient age at the time of diagnosis was 10.1 years old (SD 6.0). Ninety patients (54%) were male. One hundred four patients (62%) presented with hemorrhage from at least 1 CM, 58 (35%) with seizures with or without CM hemorrhage, and 43 (26%) with incidental lesions. Twenty-five patients (15%) had multiple CMs, 17 (10%) had a family history of CMs, and 33 (20%) had radiologically apparent developmental venous anomalies (DVAs). The overall annual hemorrhage rate was 3.3%. Permanent neurological morbidity was 29% per hemorrhage, increasing to 45% for brainstem, thalamic, or basal ganglia CM and decreasing to 15% for supratentorial lobar or cerebellar lesions. The annual hemorrhage rate for incidental CMs was 0.5%; for hemorrhagic CMs, it was 11.3%, increasing to 18.2% within the first 3 years. Hemorrhage clustering within 3 years was statistically significant (HR 6.1, 95% CI 1.72-21.7, p = 0.005). On multivariate analysis, hemorrhagic presentation (HR 4.63, 95% CI 1.53-14.1, p = 0.007), brainstem location (HR 4.42, 95% CI 1.57-12.4, p = 0.005), and an associated radiologically apparent DVA (HR 2.91, 95% CI 1.04-8.09, p = 0.04) emerged as significant risk factors for hemorrhage, whereas age, sex, CM multiplicity, and CM family history did not. CONCLUSIONS Prior hemorrhage, brainstem location, and associated DVAs are significant risk factors for symptomatic hemorrhage in children with CMs. Hemorrhage clustering within the first 3 years of a bleed can occur, a potentially important factor in patient management and counseling.
Interventional neuroradiology in children: diagnostics and therapeutics. - Current opinion in pediatrics
To highlight the spectrum of pediatric neurovascular conditions typically referred for diagnostic or interventional neuroangiography, the range of techniques available in contemporary pediatric neurointerventional practice, and the specific considerations relating to radiation and contrast dosing applicable to pediatric neurointerventional procedures.Neurointerventional procedures are increasingly utilized in children for a variety of indications, with continuous emphasis on improving safety and treatment effectiveness. Numerous steps can be taken to mitigate the potential risks of pediatric neurointerventional procedures, with recent data from high-volume centers suggesting similar, if not lower, complication rates in children compared with adults. Judicious patient selection and clarity of goals are critically important, however, because children undergoing complex and lengthy neurointerventional procedures are particularly vulnerable to the effects of ionizing radiation, vessel injury, and contrast overload.With continued advances in endovascular technology, neurointerventionalists stand to play an important and expanding role in the multidisciplinary management of pediatric neurovascular disease.
Pediatric central nervous system vascular malformations. - Pediatric radiology
Pediatric central nervous system (CNS) vascular anomalies include lesions found only in the pediatric population and also the full gamut of vascular lesions found in adults. Pediatric-specific lesions discussed here include infantile hemangioma, vein of Galen malformation and dural sinus malformation. Some CNS vascular lesions that occur in adults, such as arteriovenous malformation, have somewhat distinct manifestations in children, and those are also discussed. Additionally, children with CNS vascular malformations often have associated broader vascular conditions, e.g., PHACES (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies, eye anomalies and sternal anomalies), hereditary hemorrhagic telangiectasia, and capillary malformation-arteriovenous malformation syndrome (related to the RASA1 mutation). The treatment of pediatric CNS vascular malformations has greatly benefited from advances in endovascular therapy, including technical advances in adult interventional neuroradiology. Dramatic advances in therapy are expected to stem from increased understanding of the genetics and vascular biology that underlie pediatric CNS vascular malformations.
Optimizing cerebrovascular surgical and endovascular procedures in children via personalized 3D printing. - Journal of neurosurgery. Pediatrics
OBJECT Despite the availability of multiplanar imaging, understanding relational 3D anatomy for complex cerebrovascular lesions can be difficult. A 3D printed model allows for instantaneous visualization of lesional anatomy from all perspectives, with the added ability to simulate operative approaches with tactile feedback. The authors report their experience with customized 3D printed models of pediatric cerebrovascular lesions as an educational and clinical tool for patients, trainees, and physicians. METHODS Via an "in-house" 3D print service, magnetic resonance imaging (MRI) and computerized tomography (CT) studies of pediatric patients with arteriovenous malformations (AVMs) were processed with specialized software, and regions of interest were selected by the surgical/endovascular team. Multiple models for each patient were then printed on a 3D printer, with each construct designed to illustrate different aspects of the specific lesion. Intraoperative validation of model fidelity was performed using perioperative imaging, surgical filming, and post hoc analysis of models with intraoperative photography. RESULTS Four cases involving pediatric patients (ages 0-16 years) were studied for initial proof of principle. Three of the patients had AVMs and one had a vein of Galen malformation (VOGM). The VOGM was embolized successfully and the AVMs were resected without complication. In the AVM cases, intraprocedural imaging and photography were performed and verified millimeter-level fidelity of the models (n = 5, 98% concordance, range 94%-100% with average of < 2 mm variation in the largest AVM [6-cm diameter]). The use of 3D models was associated with a 30-minute reduction in operative time (12%) in 2 cases when they were compared with matched controls as a feasibility study. CONCLUSIONS Patient-specific 3D printed models of pediatric cerebrovascular conditions can be constructed with high fidelity. This proof-of-principle series demonstrates, for the first time, confirmation of model accuracy using intraprocedural assessment and potential benefit through shortened operative time.
Safety of neuroangiography and embolization in children: complication analysis of 697 consecutive procedures in 394 patients. - Journal of neurosurgery. Pediatrics
The safe treatment of children using catheter-based angiography and embolization poses unique challenges because of the technical factors regarding the size and fragility of access and target vessels, as well as unique pediatric cerebrovascular pathologies. The complication rates for neurointerventional procedures in children have not been established.The records of a consecutive cohort of pediatric patients who underwent neuroangiography and/or embolization between 2007 and 2013 were reviewed retrospectively to identify both intraprocedural and postprocedural complications. Demographic and clinical risk factors were analyzed with a multivariate logistic regression model.The 697 consecutive procedures consisted of 429 diagnostic angiograms and 268 embolizations (mean age of patients 11.1 years; range 4 days to 18 years; 217 females). There were 130 intracranial, 122 extracranial, and 16 spinal embolizations. Pathologies included 28 intracranial arteriovenous malformations (AVMs), 12 spinal AVMs, 19 aneurysms, 29 vein of Galen malformations, 29 dural arteriovenous fistulas, 96 extracranial AVMs, 39 tumors, 3 strokes, and 13 others. Overall, 2 intraprocedural and 1 postprocedural complication (0.7%) occurred in the diagnostic group, all of which were nonneurological events. In the embolization group, 7 intraprocedural and 11 postprocedural complications (6.7%) were observed. Of these complications, 15 were nonneurological events (5.6%), 1 was a short-term neurological event (0.4%), and 2 were long-term neurological events (0.7%).Neither the technical challenges posed by children's access and target vessels nor the unique neuro-vascular pathologies seen in children need result in an elevated morbidity rate related to neuroangiography and embolization. At a dedicated high-volume center, the complication rates may be lower than those for comparable procedures performed in adults.
Lower vertebral-epidural spinal arteriovenous fistulas: a unique subtype of vertebrovertebral arteriovenous fistula, treatable with coil and Penumbra Occlusion Device embolization. - Journal of neurointerventional surgery
A vertebral-epidural spinal arteriovenous fistula (AVF) is an abnormal arteriovenous shunt connecting the vertebral artery to the spinal epidural venous plexus, and may occur spontaneously or secondary to a variety of causes. These unique lesions are uncommon in adults and rarer still in children. Previous reports have grouped together a heterogeneous collection of such arteriovenous lesions, including arterial contributions from the upper and lower vertebral artery, with venous drainage into a variety of spinal and paraspinal collectors. Here, through two cases, we delineate a distinct entity, the lower vertebral-to-epidural AVF. The salient clinical and anatomic features are summarized and contextualized within the broader constellation of vertebrovertebral AVF, the utility of a transarterial intravenous/retrograde intra-arterial endovascular approach is highlighted, and a new use of the Penumbra Occlusion Device (Penumbra Inc) for this purpose is reported.Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Intracranial aneurysms in the youngest patients: characteristics and treatment challenges. - Pediatric neurosurgery
Characteristics and treatment challenges of aneurysms in young children differ from those in older pediatric patients.Records of children undergoing cerebral or spinal angiography by the senior neurointerventionalist (D.B.O.) from October 2006 to January 2014 were reviewed to identify patients with digital subtraction angiography-confirmed intracranial aneurysms. Demographics, presentation, subtype of aneurysm, treatment strategy, and outcome were evaluated.Of 763 pediatric cases, 33 were of children harboring cerebral aneurysms. Overall, 48% were male, 24% presented with hemorrhage and 67% harbored fusiform/dissecting aneurysms. Patients aged 0-10 years were significantly more likely to harbor nonsaccular, dissecting/fusiform aneurysms (84 vs. 43%, p = 0.02). A total of 13/22 pediatric patients harboring dissecting/fusiform aneurysms were male (59%) compared to 3/11 with saccular aneurysms (27%, p = 0.14). Overall, 15 patients underwent endovascular treatment (45%) and 8 underwent microsurgical treatment (24%). There was no significant difference in treatment approach based on patient age or aneurysm morphology. Overall, 19/23 aneurysms were occluded after initial treatment (83%); there were 2 procedure-related complications with neurological sequelae (9%).We demonstrate that the youngest patients (10 years and under) have aneurysms even more distinct and less similar to adult aneurysms than those in the larger pediatric cohort.
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300 Longwood Ave Children's Hospital Boston - Neuroradiology Boston, MA 02115
75 Francis St, Pbb-A 4Th Floor Brigham And Women's Hsptl, Infectious Disease Div.
75 Francis St Department Of Ob Gyn
Channing Lab Room 461 181 Longwood Avenue
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