Case Report: Signal Drop on MRA Imaging of the Internal Carotid Artery after Neuroform Stent Placement

Magnetic resonance angiography (MRA) is an important tool in evaluating the patency of vessels which have previously been stented. Neuroform stents (Boston Scientific, Natick, MA, U.S.A.) are utilized to provide a scaffold across the neck of an aneurysm. These stents are synthesized from Nitinol (nickel and titanium) and thus cause minimal distortion upon imaging with MRA. Patients who have undergone Neuroform stent assisted coiling of aneurysms are routinely followed with MRA to delineate stenosis of the stented segment of vessel as well as recurrence of the aneurysms. While numerous reports show that Neuroform stents do not lead to MRA imaging artifact, we report of a case where the utilization of the Neuroform stent led to a signal drop out at the site of the stent upon evaluation with MRA and thus led to further invasive radiological procedures

Sensitivity-analysis method for inverse simulation application

An important criticism of traditional methods of inverse simulation that are based on the Newton–Raphson algorithm is that they suffer from numerical problems. In this paper these problems are discussed and a new method based on sensitivity-analysis theory is developed and evaluated. The Jacobian matrix may be calculated by solving a sensitivity equation and this has advantages over the approximation methods that are usually applied when the derivatives of output variables with respect to inputs cannot be found analytically. The methodology also overcomes problems of input-output redundancy that arise in the traditional approaches to inverse simulation. The sensitivity- analysis approach makes full use of information within the time interval over which key quantities are compared, such as the difference between calculated values and the given ideal maneuver after each integration step. Applications to nonlinear HS125 aircraft and Lynx helicopter models show that, for this sensitivity-analysis method, more stable and accurate results are obtained than from use of the traditional Newton–Raphson approach

Redefining Onyx HD 500 in the Flow Diversion Era

We report the largest US case series results using Onyx HD-500 (EV3), a new liquid embolic agent, in the successful treatment of 21 patients with wide-neck intracranial aneurysms (mean size 4.5 mm), which are at increased risk of incomplete occlusion or recanalization with standard endovascular intervention utilizing detachable platinum coils. All aneurysms were located in the anterior circulation, and three aneurysms presented as acute subarachnoid hemorrhages. Complete aneurysm occlusion was present in 19 of 21 patients (90%). On six-month followup, one patient with an initially small residual neck progressed to total occlusion. Aneurysm recanalization was not detected in any patients on mean follow up of 8.9 months in 11 patients. Four patients experienced transient neurologic deficits in the immediate postoperative period and one in a delayed fashion. Embolization with the liquid embolic agent Onyx appears to be a safe and effective endovascular modality of treatment for wide-neck aneurysms or recurrent aneurysms that had previously failed treatment with detachable coils

Ensuring Healthy American Indian Generations for Tomorrow through Safe and Healthy Indoor Environments

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author’s publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.American Indians (AI) have the highest rate of severe physical housing problems in the U.S. (3.9%). Little information exists about the environmental hazards in AI homes. The purposes of this paper are to discuss challenges that were encountered when recruiting AI for a home-and employment-based environmental health assessments, highlight major successes, and propose recommendations for future indoor environmental health studies. The Center for American Indian Community Health (CAICH) and Children’s Mercy Hospital’s Center for Environmental Health and Allergy and Immunology Research Lab collaborated to provide educational sessions and healthy home assessments for AI. Through educational trainings, more than 240 AI were trained on the primary causes of health problems in homes. A total of 72 homes and places of employment were assessed by AI environmental health specialists. The top three categories with the most concerns observed in the homes/places of employment were allergens/dust (98%), safety/injury (89%) and chemical exposure (82%). While some information on smoking inside the home was collected, these numbers may have been underreported due to stigma. This was CAICH’s first endeavor in environmental health and although challenges arose, many more successes were achieved

Paradoxical Worsening of Ocular Symptoms after Spontaneous Closure of a Carotid Cavernous Fistula: Case Report

We report an interesting case of a spontaneous occlusion of a carotid cavernous fistula (CCF) causing a paradoxical worsening of orbital symptoms. A 59-year-old woman presented to our institution with conjunctival injection, raised intraocular pressures (IOP) and mild exophthalmos of her left eye. A digital subtraction angiography (DSA) demonstrated a Type-D CCF draining into the left superior ophthalmic vein (SOV). The patient declined endovascular treatment. She presented 15 months later with acute exacerbation of her orbital signs and symptoms. A DSA showed no evidence of arteriovenous fistula, and a brain MRI was consistent with spontaneous thrombosis of the SOV. At her 2-week clinical assessment, the patient showed clinical improvement and her IOP were within normal limits. Spontaneous thrombosis of the SOV can trigger the obliteration of a CCF with possible paradoxical worsening of orbital symptoms. DSA is the gold standard of diagnosis and management is directed toward decreasing IOP. Introduction We present an interesting case of a type-D carotid cavernous fistula (CCF) that closed spontaneously with a paradoxical worsening of the symptoms due to thrombosis of the superior ophthalmic vein (SOV). The authors also give directives for the management of these extremely rare cases

Understanding the strong intervening O VI absorber at z_abs 0.93 towards PG1206+459

Large scale structure and cosmolog

The evolution of the low-density H i intergalactic medium from z = 3.6 to 0: Data, transmitted flux, and H i column density

We present a new, uniform analysis of the H i transmitted flux (F) and H i column density (N_{mathrm{H,{small I}}}) distribution in the low-density IGM as a function of redshift z for 0 < z < 3.6 using 55 HST/COS FUV (Δz = 7.2 at z < 0.5), five HST/STIS + COS NUV (Δz = 1.3 at z ∼1) and 24 VLT/UVES, and Keck/HIRES (Δz = 11.6 at 1.7 < z < 3.6) AGN spectra. We performed a consistent, uniform Voigt profile analysis to combine spectra taken with different instruments, to reduce systematics and to remove metal-line contamination. We confirm previously known conclusions on firmer quantitative grounds in particular by improving the measurements at z ∼1. Two flux statistics at 0 < F < 1, the mean H i flux and the flux probability distribution function (PDF), show that considerable evolution occurs from z = 3.6 to z = 1.5, after which it slows down to become effectively stable for z < 0.5. However, there are large sightline variations. For the H i column density distribution function (CDDF, f ∝ N_{ m H,{small I}}^{-eta }) at log (N_{mathrm{H,{small I}}}/1, {mathrm{cm}^{-2}}) [13.5, 16.0], β increases as z decreases from β = 1.60 at z ∼3.4 to β = 1.82 at z ∼0.1. The CDDF shape at lower redshifts can be reproduced by a small amount of clockwise rotation of a higher-z CDDF with a slightly larger CDDF normalization. The absorption line number per z (dn/dz) shows a similar evolutionary break at z ∼1.5 as seen in the flux statistics. High-N_{mathrm{H,{small I}}} absorbers evolve more rapidly than low-N_{mathrm{H,{small I}}} absorbers to decrease in number or cross-section with time. The individual dn/dz shows a large scatter at a given z. The scatter increases towards lower z, possibly caused by a stronger clustering at lower z

Acute Stroke Intervention In Young Patients

Purpose: Stroke is a disease of the elderly, however it can affect the younger patients. We present a retrospective review of our series of young patients (55 years old and younger), treated at our institution from 2007 to 2012, to assess the safety, efficacy and patient outcome of multimodal endovascular treatment in this patient population. Methods: A total of 42 patients underwent multimodal endovascular revascularization for acute ischemic events. Recanalization rates were assessed using the Thrombolysis in Myocardial Infarction (TIMI)and clinical outcomes were assessed using the Modified Rankin Scale (mRS) obtained at discharge and follow-up visits. Patient demographics, medical co-morbidities, treatment complications and mortality data were collected and analyzed. Results: Of 42 patients, an improvement in Thrombolysis in Myocardial Infarction score (TIMI score) was noted in 38 patients (90.47%). The average modified Rankin Scale score on discharge was 3.2 with 25 patients (60%) having a favorable score of 0-3. All 21 patients (100%) with available clinical follow-up had a favorable mRS score (mean follow-up of 10.4 months). Symptomatic intracranial hemorrhage occurred in four patients (9.5%); none required surgery. Three fatalities resulted from intraoperative vessel rupture (7.14%). Conclusion: We observed good recanalization rates and favorable clinical outcomes after endovascular stroke intervention in young patients. Also, there was a low morbidity and mortality rate overall. Therefore multimodal endovascular recanalization of acute ischemic stroke is an effective treatment in younger patients, which justifies aggressive management of those patients