7 documents found, page 1 of 1

Non-invasive derivation of instantaneous free-wave ratio from invasive coronary...

Invasive coronary physiology is underused and carries risks/costs. Artificial Intelligence (AI) might enable non-invasive physiology from invasive coronary angiography (CAG), possibly outperforming humans, but has seldom been explored, especially for instantaneous wave-free Ratio (iFR). We aimed to develop binary iFR lesion classification AI models and compare them with human performance. single-center retrospe...

Preface

Old habits die hard: Can AI help bring coronary angiography Into the 21st Century?

Coronary angiography (CAG) was pioneered in the 1950s by Eduardo Coelho (who performed the first nonselective in vivo CAG in 1952 at the Santa Marta Hospital in Lisbon, Portugal) and Frank Mason Sones Jr (who performed the first selective CAG in vivo in 1958 at the Cleveland Clinic in Ohio, USA). Sones further developed the technique by contributing to the development of the C-arm, enabling multiangular views a...

Coronary X-ray angiography segmentation using Artificial Intelligence: a multic...

Introduction: We previously developed an artificial intelligence (AI) model for automatic coronary angiography (CAG) segmentation, using deep learning. To validate this approach, the model was applied to a new dataset and results are reported. Methods: Retrospective selection of patients undergoing CAG and percutaneous coronary intervention or invasive physiology assessment over a one month period from four cen...

On the suitability of suffix arrays for lempel-ziv data compression

Lossless compression algorithms of the Lempel-Ziv (LZ) family are widely used nowadays. Regarding time and memory requirements, LZ encoding is much more demanding than decoding. In order to speed up the encoding process, efficient data structures, like suffix trees, have been used. In this paper, we explore the use of suffix arrays to hold the dictionary of the LZ encoder, and propose an algorithm to search ove...

On the use of suffix arrays for memory-efficient Lempel-Ziv data compression

The Lempel-Ziv 77 (LZ77) and LZ-Storer-Szymanski (LZSS) text compression algorithms use a sliding window over the sequence of symbols, with two sub-windows: the dictionary (symbols already encoded) and the look-ahead-buffer (LAB) (symbols not yet encoded). Binary search trees and suffix trees (ST) have been used to speedup the search of the LAB over the dictionary, at the expense of high memory usage [1]. A suf...

Suffix Arrays: A competitive choice for fast Lempel-Ziv Compression

Lossless compression algorithms of the Lempel-Ziv (LZ) family are widely used in a variety of applications. The LZ encoder and decoder exhibit a high asymmetry, regarding time and memory requirements, with the former being much more demanding. Several techniques have been used to speed up the encoding process; among them is the use of suffix trees. In this paper, we explore the use of a simple data structure, n...