Tiny Wireless Pacemaker

New development by a start-up company called Nanostim that was recently acquired by st. Jude Medical of a pacemaker about the size of a AAA battery that can be inserted into the heart using a catheter and will last for 9 to 13 years without any leads or wires required.

Check out the coverage on: Teeny Tiny Pacemaker Fits Inside the Heart

CARS 2013 - Cardiovascular and Angiographic Imaging

The first presentation in this session was by Tuncay on segmentation of the aortic valve area on CT. They have deviced a novel method to semi automatically segment the opening area of the aortic valve. They created an adaptive grayscale image to get the boundaries more clear and an adaptive algorithm to remove the calcium from the image. The technique proved effective and more reproducible in 21 patient datasets.

The second presentation by Haase was on Model based 3D registration of a CS catheter: application to single X-ray projections from a rotational angiographic sequence. They use a model of the catheter and combine this with the recorded Xray data to obtainna 3D representation of the orientation and movement of the catheter in 3D. They showed high accracy in the tracking in a simulated phantom setup. In clinical datasets also a high accuracy was obtained. Overall accuracy was 0.33 mm in 2D and 2.04 mm in 3D.

The third and final presentation by Masuda was on full automatic calculation of ejection fraction of left ventricle from either of short-axis view by processing succesive ultrasound images. The aim of their study was to design a method that does not require any initial input of the user. They envision to include this algorithm into a portable echography device for use in emergency situations. They demonstrate an interactive real-time detection of the LV cavity during the acquisition of the ultrasound. A subjective scoring by sonographers showed a high level of correct segmentation. Their algortihm was succesfull both in two and four chamber view. Good correlation was shown of the EF based on the new and conventional method.

Publication: Postprocessing Pitfalls in Using CT for Global LV Function

This paper is a overview of the work we did on the evaluation of Left Ventricular (LV) function using Computed Tomography (CT). Earlier papers have already covered several aspects of this measurement. This paper, based on our poster presentation at RSNA 2010 provides a good overview of the problems that can arise in LV measurement.

Informatics in Radiology: Postprocessing Pitfalls in Using CT for Automatic and Semiautomatic Determination of Global Left Ventricular Function.
van Ooijen PM, de Jonge GJ, Oudkerk M.
Radiographics. 2012 Mar;32(2):589-99. 


Abstract
Recent advances in technical capabilities of computed tomographic (CT) scanners, including an increasing number of detector rows, improved spatial and temporal resolution, and the development of retrospective gating, have allowed the acquisition of four-dimensional (4D) datasets of the beating heart. As a result, the heart can be visualized in different phases and CT datasets can be used to assess cardiac function. Many software packages currently exist that allow automatic or semiautomatic evaluation of left ventricular function on the basis of 4D CT datasets. The level of automation varies from extensive, completely manual segmentation by the user to fully automatic evaluation of left ventricular function without any user interaction. Although the reproducibility of functional parameter assessment is reported to be high and intersoftware variability low for larger groups of patients, significant differences can exist among measurements obtained with different software tools from the same dataset. Thus, careful review of automatically or semiautomatically obtained results is required.

Enhanced four-dimensional presentation of cardiac CT data

Demonstrated again at the ESCR 2011 in Amsterdam last week, the PhyZiodynamic software of Ziosoft Inc. Incredible what they can do based on 4D imaging data obtained from CT. With advanced computing techniques they compute a fluent 4D moving heart with increased temporal and spatial resolution. Technically it is possible, as they demonstrate, and now they are looking for the clinical applications.

PhyZiodynamic solutions are based on uncompressed imaging data, using off-the-shelf hardware. Ziosoft's revolutionary PhyZiodynamic algorithms utilizes non-rigid (deformable) registration on lossless temporal images to reduce noise, improve motion coherence, and enable functional analytics.
 
Look at their website for some example movies.