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author:("Shah, vaisar")
1.  Enrollment of Research Subjects through Telemedicine Networks in a Multicenter Acute Intracerebral Hemorrhage Clinical Trial: Design and Methods 
Enrollment of subjects in acute stroke trials is often hindered by narrow timeframes, because a large proportion of patients arrive via transfers from outside facilities rather than primary arrival at the enrolling hospital.
Telemedicine networks have been increasingly utilized for provision of care for acute stroke patients at facilities outside of major academic centers. Treatment decisions made through Telemedicine networks in patients with acute ischemic stroke have been shown to be safe, reliable, and effective. With the expanding use of this technology and the impediments to enrolling subjects into clinical trials, this approach can be applied successfully to the field of clinical research.
Methods and Conclusions:
The antihypertensive treatment of acute cerebral hemorrhage II trial is a phase III randomized multicenter trial that has developed a protocol in collaboration with participating sites to implement the use of Telemedicine networks for the enrollment of research subjects. The protocol describes the operating procedures and legal and Institutional Review Board perspectives for its implementation.
PMCID: PMC3693995  PMID: 23826435
2.  Reversal of CT hypodensity after acute ischemic stroke 
We report a man admitted to the hospital after sustaining an ischemic stroke, with a return to isodensity on repeat computed tomography (CT) scan noted at day 9 of his hospital stay. This finding, known as the “fogging effect,” has never been noted so early in a patient’s course on CT imaging.
computed tomography
magnetic resonance imaging
PMCID: PMC3693996  PMID: 23826437
3.  Clinical Outcome of Patients with Acute Posterior Circulation Stroke and Bilateral Vertebral Artery Occlusion 
Background and Introduction:
Patients presenting with posterior circulation acute ischemic events are occasionally noted to have occlusion of bilateral vertebral arteries with basilar artery blood flow entirely dependent from the anterior circulation. There is limited data about prognosis of such patients in literature.
Patients with acute posterior circulation ischemic stroke and bilateral vertebral artery occlusion (including contra-lateral hypoplastic vertebral artery without contribution to the basilar artery system) were identified prospectively from two academic centers. Data including clinical presentation, medical management, angiographic findings, recurrent events and outcome were collected and reported.
A total of 4 patients presenting with acute ischemic events in the posterior circulation were identified to have bilateral vertebral artery occlusion at our center. One additional patient had a vertebral artery occlusion and a contra-lateral hypoplastic vertebral artery. In the functional evaluation of the blood flow with catheter angiography, the basilar artery was filling from the anterior circulation, with no antegrade flow from bilateral vertebral arteries injection in all 5 patients. Patients were treated with anti-platelets (n=4) or started on anti-coagulation after failing anti-platelet therapy (n=2). All patients had recurrent ischemic stroke with new ischemic lesions proven by diffusion weighted images on MRI within 2 to 70 days after the initial event.
Patients with acute posterior circulation ischemic stroke and bilateral vertebral artery occlusion are at high risk of having early recurrent ischemic events. Reestablishment of the antegrade vertebro-basilar blood flow through endovascular re-canalization might be an option to decrease stroke recurrence in selected patients with acute posterior circulation stroke and bilateral vertebral artery occlusion.
PMCID: PMC3317285  PMID: 22518265
vertebral artery occlusion; bilateral; ischemic stroke; prognosis
4.  Transcranial Optical Monitoring of Cerebrovascular Hemodynamics in Acute Stroke Patients 
Optics express  2009;17(5):3884-3902.
“Diffuse correlation spectroscopy” (DCS) is a technology for non-invasive transcranial measurement of cerebral blood flow (CBF) that can be hybridized with “near-infrared spectroscopy” (NIRS). Taken together these methods hold potential for monitoring hemodynamics in stroke patients. We explore the utility of DCS and NIRS to measure effects of head-of-bed (HOB) positioning at 30°, 15°, 0°, −5° and 0° angles in patients with acute ischemic stroke affecting frontal cortex and in controls. HOB positioning significantly altered CBF, oxy-hemoglobin (HbO2) and total-hemoglobin (THC) concentrations. Moreover, the presence of an ipsilateral infarct was a significant effect for all parameters. Results are consistent with the notion of impaired CBF autoregulation in the infarcted hemisphere.
PMCID: PMC2724658  PMID: 19259230
5.  Spontaneous Recanalization after Complete Occlusion of the Common Carotid Artery with Subsequent Embolic Ischemic Stroke 
Acute carotid artery occlusion carries a high morbidity and mortality. Acute angioplasty and stenting is a feasible option with little known about the long term outcome. Limiting factor for this approach is hyperperfusion syndrome or hemorrhagic infarction. Spontaneous early or late recanalization for extracranial vessel is in the range of 5% –30%, with no well defined clinical outcome data. We describe a case of spontaneous common carotid recanalization.
Case Report:
An 88 year old man presented with right sided weakness, global aphasia and visual field loss and was discovered to have common carotid occlusion at its origin. Within 12 hours of symptom onset patient improved neurologically to his baseline exam and repeat imaging demonstrated spontaneous recanalization. This was followed symptomatic occlusion of left middle cerebral artery The patient was treated with multimodality approach resulting in complete revascularization of the middle cerebral artery and angioplasty and stent placement of the internal carotid artery. Patient had a good neurological outcome at 3 months followup.
The present case report demonstrates the risk of spontaneous recanalization acutely in patients presenting with common carotid artery occlusion and associated risk of embolic strokes. In such a patient, concomitant treatment for intracranial occlusion and extracranial high grade stenosis may be performed safely after 30 hours from the initial symptom onset.
PMCID: PMC3317333  PMID: 22518244
Carotid artery occlusion; Recanalization; Acute Stroke
6.  Bilateral Tri-Arterial Embolization for the Treatment of Epistaxis 
Intractable epistaxis is treated by ipsilateral trans-arterial embolization of the internal maxillary artery, but there is 13–26% recurrence of bleeding. Preemptive embolization of both internal maxillary arteries along with the ipsilateral facial artery could provide maximal protection against recurrent epistaxis. We report our experience with 8 patients treated with bilateral tri-arterial embolization.
We performed a retrospective review of the patients who were treated with bilateral internal maxillary artery and ipsilateral facial artery embolization from January 2005 to January 2007. All patients had bleeding that was refractory to nasal packing.
Eight patients were treated with bilateral tri-arterial embolization. The median age was 65 years (range, 35–90 years). Risk factors included hypertension (n=4), smoking (n=2), alcohol (n=2), and use of anticoagulation (n=2). All but 2 of the patients were treated under local anesthesia. All patients had complete obliteration of bleeding during the procedure, with no residual vascular blush. No major peri- or post-procedural complications were noted. Patients stayed in the hospital for 2–4 days (average 2.6 days). One patient developed ipsilateral temporofacial pain which resolved during hospitalization. Another patient had minor recurrent epistaxis on post operative day 2 which resolved with temporary repacking and the patient was discharged the next day.
In our experience with 8 cases, bilateral internal maxillary artery and/or ipsilateral facial artery embolization was achieved without complication and was associated with complete obliteration of vascular blush and no significant recurrent epistaxis.
PMCID: PMC3317326  PMID: 22518233
Epistaxis; arterial embolization; internal maxillary artery; polyvinyl alcohol particles
7.  Adjunct bivalirudin dosing protocol for neuro-endovascular procedures 
To introduce a protocol for anticoagulation using bivalirudin in neuro-endovascular procedures.
Three different bivalirudin dosing protocols were used in four consecutive patients undergoing neuro-endovascular procedures. Activated clotting time (ACT) was closely monitored to assess the effect of bivalirudin on ACT. Target ACT was set at 300–350 seconds.
The first dosing protocol led to largely supra-therapeutic ACT values. With the second protocol, ACT remained sub-therapeutic for 25 minutes (33% of monitoring time). The third protocol was applied to two patients and it showed the best results with the ACT being in the therapeutic range for 72% of the combined monitoring time and never exceeding 366 seconds.
The dosing of bivalirudin needs to be adjusted for the use in neuro-endovascular procedures. We are proposing a protocol that seems to provide safe and effective anticoagulation. The safety and efficacy of bivalirudin in neuroendovascular procedures will need to be further validated in future studies.
PMCID: PMC3317312  PMID: 22518219
anticoagulation; bivalirudin; carotid angioplasty; intracranial angioplasty

Results 1-7 (7)