Dhruvil J. Pandya

Measurement of Antiplatelet Inhibition during Neurointerventional Procedures: The Effect of Antithrombotic Duration and Loading Dose

Symptomatic thromboembolic events are the most common complications associated with aneurysm coiling, and carotid and intracranial stenting. Our objective is to assess the effect of aspirin (ASA) and clopidogrel dose and duration on platelet inhibition using a point of care assay in neurointerventional (NI) suite.

Endovascular embolization of head and neck tumors

Endovascular tumor embolization as adjunctive therapy for head and neck cancers is evolving and has become an important part of the tools available for their treatment. Careful study of tumor vascular anatomy and adhering to general principles of intra-arterial therapy can prove this approach to be effective and safe. Various embolic materials are available and can be suited for a given tumor and its vascular supply. This article aims to summarize current methods and agents used in endovascular head and neck tumor embolization and discuss important angiographic and treatment characteristics of selected common head and neck tumors.

Merci mechanical thrombectomy retriever for acute ischemic stroke therapy Literature review

Background: Mechanical thrombectomy is a promising adjuvant or stand-alone therapy for acute ischemic stroke (AIS) caused by occlusion of a large vessel in patients beyond the systemic thrombolysis therapeutic window. This review focuses on the clinical and angiographic outcomes of mechanical thrombectomy with use of the Merci retriever device. Methods: Available literature published to date on the major trials and observational studies involving the Merci retriever was reviewed. In addition to the review, results from studies involving the Merci retriever were compared to results from Prolyse in Acute Cerebral Thromboembolism II (PROACT II) and the Penumbra device studies. The predictors for favorable outcome following revascularization with the Merci device were reviewed on the basis of published stratified analyses. Favorable clinical outcome was defined in the Merci experience by a modified Rankin Scale (mRS) score of ≤2 at 90 days following AIS. Results: Presented in this review are a total of 1,226 patients treated with the Merci device; 305 patients are from 2 pivotal trials involving the device, and the remaining 921 patients are from observational studies in the Merci registry. The 90-day mRS of ≤2 was achieved in 32% of the patient group, with an overall mortality rate of 35.2%. Symptomatic intracerebral hemorrhage was identified in 7.3% of patients treated with Merci retriever, a result comparable to that in the PROACT II and Penumbra thrombectomy trials. Successful recanalization, lower NIH Stroke Scale score, and younger age were identified as the strongest predictors of favorable outcomes. Conclusion: Mechanical thrombectomy with the Merci retriever device is a safe treatment modality for AIS patients presenting with a large-vessel occlusion within 8 hours of symptom onset. Although the Merci retriever showed a good recanalization rate, there are currently no randomized clinical trials to assess its clinical efficacy in comparison with systemic thrombolysis within a window of 3 to 4.5 hours or with standard of care beyond a 4.5-hour window.

Dissecting Aneurysms of Posterior Cerebral Artery: Clinical Presentation, Angiographic Findings, Treatment, and Outcome

Background: The dissecting posterior cerebral artery (PCA) aneurysms are very rare. These aneurysms pose significant treatment challenge and need careful evaluation to formulate an optimal treatment plan in case of ruptured or un-ruptured presentations. Methods: Retrospective review of a prospectively collected data. Results: Seven patients with dissecting aneurysms of the PCA were identified. Six out of seven presented with subarachnoid hemorrhage (SAH) and one with ischemic stroke. Three out of seven were treated with endovascular coil embolization without sacrifice of the parent artery and the rest had parent artery occlusion (PAO) with coil embolization. None of the patients developed new neurological deficits post-procedure. Aneurysm re-occurred in two patients that were treated without PAO. Conclusion: Endovascular treatment of the dissecting PCA aneurysm is safe and feasible. It can be performed with or without PAO. Recurrence is more common without PAO and close follow-up is warranted.

Safety and predictors of aneurysm retreatment for remnant intracranial aneurysm after initial endovascular embolization

Introduction Aneurysmal subarachnoid hemorrhage (SAH) is a rare but devastating form of stroke. Endovascular therapy has been criticized for its higher rate of recanalization and retreatment. The safety and predictors of retreatment are unknown. We report the clinical outcomes, imaging outcomes and predictors for aneurysm retreatment after initial endovascular embolization. Method We identified patients who underwent endovascular retreatment from July 2005 through November 2011. Aneurysm and patient data were collected. Periprocedural complications were reported as intraoperative perforation (IOP) or thromboembolic event (TEE). Aneurysm and patient characteristics were compared between aneurysms requiring retreatment and those not requiring retreatment to evaluate aneurysm retreatment predictors. Results A total of 111/871 (13%) aneurysms underwent retreatment. Two (0.2%) were retreated for recurrent acute SAH, 82 (74%) aneurysms were located in the anterior circulation, 47 (42%) required stent and 5 (5%) required balloon assist during retreatment. There were a total of 5 (5%) IOP and 6 (5%) TEE from which 2 (2%) and 1 (1%) were symptomatic, respectively. Overall symptomatic events rate were 2.7%. Patients were followed up for an average of 15±14 months. Seven (0.8%) aneurysms required a second retreatment without any recurrent SAH. Multivariable analysis revealed an OR for aneurysms requiring retreatment of 2.965 for aneurysms presenting as aneurysmal SAH, 1.791 for aneurysms in the posterior circulation and 1.053 for aneurysms with large dome size. Conclusions Aneurysm retreatment is a safe option without a significant increase in morbidity or mortality. SAH, posterior circulation aneurysms and larger aneurysm dome size are predictors of aneurysms requiring retreatment.

Neurologic complications in non-neurological intensive care units.

Background:Neurologists are frequently called to evaluate patients in the intensive care units who are not waking up. This often poses a diagnostic and prognostic dilemma. Review Summary:The initial evaluation starts with abstracting the prehospital and in-hospital history, followed by bedside clinical and neurologic examination to establish a differential diagnosis. The subsequent work-up is based on clinical suspicion where reversible life-threatening causes should be immediately identified. After confirming the diagnosis and implementation of the appropriate medical management, a prompt family meeting and counseling is recommended. The role of neurologists in clinical diagnosis and prognostication of the coma patient, as well as diagnosing brain death is instrumental. Conclusions:In this review, we explore a practical systematic approach to patients with decreased level of consciousness. The most common causes of impaired alertness in different non-neurologic critical care units and commonly used prognostication tools are presented. Finally a brief introduction of hypothermia, a novel therapeutic approach is also discussed.