There are no disease modifying therapies for Huntington's (HD), a rare but fatal genetic neurodegenerative condition. To develop and test new management strategies, better understanding of the mechanisms underlying HD progression is needed. Aberrant changes in thalamo-cortical striato-cerebellar circuitry have been observed asymptomatic HD, along with transient enlargement dentate nucleus. evaluate relationship between thalamo-cerebellar connectivity progression. Prospective retrospective....

Background Pathophysiological changes of Huntington's disease (HD) can precede symptom onset by decades. Robust imaging biomarkers are needed to monitor HD progression, especially before the clinical onset. Purpose To investigate iron dysregulation and microstructure alterations in subcortical regions as biomarkers, associate such with motor cognitive impairments. Study Type Prospective. Population Fourteen individuals premanifest (38.0 ± 11.0 years, 9 females; far‐from‐onset N = 6,...

The Gyro centrifugal pump, PI (permanently implantable) series, is being developed as a totally implantable artificial heart. Our final goal to establish "functional TAH," biventricular assist system (BiVAS) with pumps. A plastic prototype 601, was evaluated through in vitro and vivo studies single ventricular device (VAD). Based upon these results, the pump head material converted titanium alloy, actuator modified. These pumps, 700 also were subjected studies. 601 series have same inner...

Abstract: The Baylor Gyro permanently implantable centrifugal blood pump (Gyro PI pump) has been under development since 1995 at College of Medicine. Excellent results were achieved as a left ventricular assist device (LVAD) with survival up to 284 days. Based on these results, we are now focusing the biventricular (BVAD) system, which requires 2 pumps be implanted simultaneously in preperitoneal space. Our hypothesis was that would an appropriate for BVAD system. 700 is fabricated from...

Abstract: A majority of the cardiopulmonary bypass (CPB) systems still utilize bulky roller pumps. direct‐drive small centrifugal pump intended for second‐generation CPB has been developed. The a 50 mm diameter impeller and provides 6 L/min flow at 3,000 rpm against 300 Hg. flexible drive shaft allows us to separate head from console resulting in easier manipulation. An vitro study showed that generated less hemolysis (index = 0.0011, comparable value Bio‐medicus BP‐80). To improve blood...

Abstract: A small and light direct‐drive centrifugal pump has been developed for cardiopulmonary bypass. In the development process, blood compatibility studies including a hemolysis study, an in vitro fluid dynamic performance vivo durability feasibility were performed. The with 50 mm diameter impeller resulted almost same index of value as did Bio‐Medicus pump. Heat dissipation from motor was prevented by using flexible drive cable. Forty‐eight‐hour sealing around driving axis accomplished...

Quantitative susceptibility mapping (QSM) is a promising tool for investigating iron dysregulation in neurodegenerative diseases, including Huntington's disease (HD). Many diverse methods have been proposed to generate accurate and robust QSM images. In this study, we evaluated the performance of different dipole inversion algorithms iron-sensitive imaging at 7T on healthy subjects large age range patients with HD. We compared an iterative least-squares-based method (iLSQR), that use...

A totally implantable centrifugal artificial heart has been developed. The plastic prototype, the Gyro PI 601, passed 2 day hemodynamic tests as a functional total (TAH), week screening for anti‐thrombogenecity, and 1 month system feasibility study. Based upon these results, metallic 700 series, was subjected to long‐term in vivo left ventricular assist device (LVAD) studies of over month. series same inner dimension characteristics 601 such an eccentric inlet port, double pivot bearing...

Abstract: An implantable electromechanical ventricular assist system (VAS) intended for permanent use has been developed. It consists of a conically shaped pumping chamber, polyolefin (Hexsyn) rubber diaphragm attached to pusher‐plate, and compact roller‐screw actuator. Design stroke volume is 63 ml. The device weighs 620 g, total 348 mi. pump can provide 8 Limin flow against 120 mm Hg afterload with preload 10 Hg. inner surfaces are biolized by dry gelatin coating, inflow outflow ports...

Abstract: Pulmonary congestion due to inappropriate pump flow management is one major problem necessary avoid during long‐term biventricular assist device (BVAD) implantation. Our objective was assess the effects of pulmonary arterial rate and rates both (right left) bypass pumps. Six healthy calves, which had been implanted with a BVAD system, were selected for this retrospective study. artery flows, rates, oxygen saturation blood, pressures assessed as parameters function routine clinical...

Abstract: A permanently implantable biventricular assist device (BVAD) system has been developed with a centrifugal pump which is activated by hydraulically‐levitated impeller. The impeller floats hydraulically into the top contact position; this position prevents thrombus formation creating washout effect at bottom bearing area, common stagnant region. was subjected to in vitro studies using pulsatile mock circulation loop confirm impeller's and swinging motion produced pulsation. Eleven...

A totally implantable centrifugal artificial heart has been developed. The plastic prototype, Gyro PI 601, passed 2 day hemodynamic tests as a functional total heart, week screening for antithrombogenicity, and 1 month system feasibility. Based on these results, metallic 702, was subjected to in vivo left ventricular assist device (LVAD) studies. pump employed the which same inner dimensions characteristics including an eccentric inlet port, double pivot bearing system, magnet coupling...

The Gyro pumps were developed for long‐term circulatory support. first generation pump (C1E3) achieved 1 month paracorporeal support in chronic animal experiments; the second (PI702) implantable ventricular assist device (VAD) was successful over 6 months. objective of next is use as a totally VAD and pediatric This tiny (KP101) fabricated with same design concept other pumps. possibility an determined after performance hemolysis test results compared to those housing impeller from...

Coil-type silicone membrane oxygenators can only be used with roller blood pumps due to the resistance from high flow. Therefore, during extracorporeal oxygenation (ECMO) treatment, combination of a pump and an oxygenator flow will induce severe hemolysis, which is serious problem. A rubber, hollow fiber that has low was developed evaluated centrifugal pumps. During in vitro tests, sufficient gas transfer demonstrated less than 3 L/min. Blood 18 mm Hg at 1 L/min This module combined Gyro...

Abstract: Centrifugal pumps are generally employed as nonpulsatile blood flow pumps; however, these can produce pulsatile by periodically alternating the impeller rotation speed. This study investigates trauma due to effect of pulse frequency and various ranges pump The hemolysis tests were conducted using Gyro C1E3 pump. was divided into following categories: Group 1 in a mode; 2 operated at 40 bpm with 30% speed variance; 3, 60 4, 70% 5, variance. A rate 3 L/min total pressure head 200 mm...

Since 1995, the Baylor College of Medicine group has been developing NEDO Gyro permanent implantable (PI) pump. The PI pump achieved outstanding results up to 284 days with no thrombus formation during left ventricular assist device (LVAD) animal experiments. However, in biventricular (BVAD) experiments, did occur. An vitro experiment showed reason for was caused by missed magnetic balance between impeller and actuator. On basis this result, revolutions per minute (RPM) suspension system...

Abstract: The Gyro C1E3 pump was developed not only for cardiopulmonary bypass but also as a short‐term assist device. main purpose of this study to examine the correlation between thrombus formation factor and pumps. Seven pumps were implanted into 3 calves evaluated different periods duration paracorporeal left ventricular device (LVAD). One subjected percutaneous support condition (PCPS) (total pressure head 500 mm Hg with flow rate L/min). anticoagulation treatment consisted continuous...

The control system for an implantable rotary blood pump is not clearly defined. A detection considered to be necessary flow monitoring and abnormal conditions such as back or a sucking phenomenon where the septum left ventricle wall sucked into cannula, etc. ultrasound flowmeter durable reliable but should totally dependent on flowmeter. If breaks, pumps have no mechanism. Therefore, authors suggest controlling by intrinsic parameter. One ventricular assist device (LVAD) calf model was...

Abstract: Due to the fact that centrifugal and axial pumps do not require valves, there is a possibility of back flow when pump speed low. To estimate minimum required prevent this regurgitation, an in vitro simulation test was conducted. A pulsatile simulated natural heart while continuous left ventricular assist device (LVAD). The LVAD attained from atrial (LA) drainage or (LV) drainage. regurgitate observed systolic phase with LA diastolic LV always provided higher than at same speed....

We proposed and developed a practical effective servo control system for rotary blood pumps. A pump assisting the failing natural heart should be operated only in physiologically acceptable conditions. The operation of is based on rotational speed impeller pressure head. If flow head are set within an range, driving condition deemed normal condition, this maintains preset operating point by applying proportional detective (PD control). or outside determined to abnormal operates recovery...

We used QSM and DTI at 7T to investigate iron dysregulation microstructure disruption in subcortical regions Huntington’s disease (HD). observed significant volume loss increased deposition the striatum globus pallidus, FA striatum. The deep cerebellar nuclei (dentate nuclei) showed a unique transient increase susceptibility premanifest patients, implicating it as new marker of HD progression that is sensitive pre-symptomatic window HD. also found varying relationships between imaging...

Physiological adaptation of the recipient to a nonpulsatile biventricular assist system (NPBVAS) is not well understood. The aim this study evaluate physiological experimental animals after NPBVAS implantation. Since May 2001, four long-term implant experiments in calves were performed. blood gas and hemodynamic data analyzed retrospectively. An additional prospective experiment was performed confirm retrospective findings. All (n = 5) lived longer than 5 weeks without complication. In...

Abstract: The NEDO Gyro PI‐710 centrifugal pump (Gyro pump) incorporates a double pivot bearing system of which the male and female bearings are fabricated from Al 2 O 3 ceramic ultrahigh molecular weight polyethylene. top is critical component because impeller levitated by hydraulic force maintained in contact position. A long‐term vitro examination was conducted using biventricular assist model. In 7 animal experiments, depth change examined. Animal experiments up to 90 days revealed that...