Electromagnetic and Acoustic Waves in Bioengineering Applications

The textbook deals with the analysis of oscillations, mechanical and electromagnetic waves and their use in medicine. The individual chapters are based on the theoretical foundations of the issue and describe the use of relevant disciplines in medical practice. The chapter on oscillations is a starting point for explaining the basic principles of waves and focuses on explaining the nature of magnetic resonance. The chapter on mechanical waves explains the nature and properties of sound, infrasound, ultrasound, and medical applications, such as lithotripsy or ultrasonography. The chapter on electromagnetic waves discusses their basic principles, origin and properties, and applications of individual frequency bands from long wavelengths to gamma radiation in therapy and diagnostics. The chapter on wave manifestations explains phenomena such as interference and diffraction and their use in applications such as optical imaging systems, holography, virtual reality, etc. The description complements the explanation of the quantum properties of radiation, which are essential for understanding applications such as laser scalpel, fluorescence microscopy, spectroscopy, generation and detection of X-rays and gamma rays. Special attention is paid to the perception of EM waves by the human eye and the perception of sound by the human ear.

Analyzing Branch‐specific Dendritic Spikes Using an Ultrafast Laser Scalpel

Dendritic spikes facilitate neuronal computation and they have been reported to occur in various regions of the dendritic tree of cortical neurons. Spikes that occur only on a select few branches are particularly difficult to analyze especially in complex and intertwined dendritic arborizations where highly localized application of pharmacological blocking agents is not feasible. Here, we present a technique based on highly targeted dendrotomy to tease out and study dendritic spikes that occur in oblique branches of cortical layer five pyramidal neurons. We first analyze the effect of cutting dendrites in silico and then confirmed in vitro using an ultrafast laser scalpel. A dendritic spike evoked in an oblique branch manifests at the soma as an increase in the afterdepolarization (ADP). The spikes are branch-specific since not all but only a few oblique dendrites are observed to evoke spikes. Both our model and experiments show that cutting certain oblique branches, where dendritic spikes are evoked, curtailed the increase in the ADP. On the other hand, cutting neighboring oblique branches that do not evoke spikes maintained the ADP. Our results show that highly targeted dendrotomy can facilitate causal analysis of how branch-specific dendritic spikes influence neuronal output.

Portable Diode Laser Scalpel in Treatment of Ingrown Toenails in Children

Introduction.The ingrown nail (onychocryptosis) is a disease that is common both among children and in adult population. Despite the fact that there is a large number of methods available for the treatment of ingrown nails, a large percentage of recurrence of the disease remains unconquered. Traditional methods of treatment today are often complemented by chemical matrixectomy, cryodestruction, electrocoagulation or laser destruction of the growth zone of the nail plate piece being removed. The purpose of all of these methods of treatment is the reduction of the recurrence of the disease. This study aims to examine the possibilities of using a portable diode laser scalpel for the treatment of ingrown nails in children.Materials and methods.In this study the authors compared treatment outcomes in patients with ingrown toenails treated with the original Winograd procedure (30 patients) with those treated with the same procedure complemented by the laser destruction of the growth zone (50 patients).Results and discussion.There was one relapse case in the study group (n=50, 2%), and two — in the control group (n=30, 6.7 %). The healing period of the postoperative wound amounted to 17.3±2.05 days in the study group and to 12.25±1.24 days in control. Pain VAS scores on the first day following the surgery were 6.2±1.24 in the study group, and 5.8±0.816 in control. Staphylococcus aureus was the pathogen responsible for the local infection process in most patients with ingrown nails.Conclusion. This study demonstrates that using the method proposed results in the reduction of the risk of recurrence of the disease from 6.7% down to 2%, increasing, however, the healing time of the postoperative wound from 12.25±1.24 to 17.3±2.05 days. This makes the use of the method proposed advisable in patients with: a stage III ingrown nail; an apparent local infectious process; a recurrent ingrown nail.