This chapter discusses the problem of continuously monitoring intraocular pressure (IOP) from an engineering perspective. It is aimed to all public in general although we think that medical staff and engineers may benefit the most from it. Although equations are included for engineers to get a glimpse of how the system works, this chapter does not go into great detail in mathematics and physics to make it understandable to medical staff. It provides though references for engineers who wish to get a better understanding of key subjects tackled in this chapter. The chapter is organized as follows: Section 1 introduces intraocular pressure (IOP) and need for its continuous monitoring. Section 2 describes the most recent efforts to develop a continuous IOP monitoring system. Section 3 shows what medical and engineering considerations must be taken into account to effectively measure IOP. Section 4 deals with health issues due to tissue warming and how to prevent them. Section 5 explains how an implant can be fabricated using either passive electronic components or active ones. Finally, Section 6 explains how the pressure sensor and the electronic circuits can be integrated.
Part of the book: Glaucoma
This Chapter focuses in the electrophysiological bases to support Trans Palpebral Electrical Stimulation TPES as a new alternative to control Intraocular Pressure IOP. Primary open Angle Glaucoma POAG is described in our approach as a dysfunction of the membrane potential of TM cells due to the dysfunction of the Maxi potassium depended Calcium Channels BKCa2+ of the Trabecular Mesh TM. We review through the paper the main contributions about Trabecular mesh dysfunction related with Voltage dependent ionic channels. We also present in this paper new results in controlling intra ocular pressure IOP during one year of trans palpebral Electric stimulation in patients with Primary open-angle glaucoma (POAG).
Part of the book: Ocular Hypertension
Conventional OCT gray scale images hidden information that do not let the physician to measure the retina oxygen blood saturation. We discuss in this chapter a new approach to extract valuable information from conventional OCT images. The main idea is to convert OCT images to colored images that let the physician to identify more easily the complex structures at the retina circulatory network. A key point in this chapter is not only to identify OCT differences through illness, but also to find a metrics to predict the percent (%) of oxygen saturation in the eye fundus. We will focus on the difficulties to measure oxygen saturation within the ocular vasculature from light reflection. Discussion concerns about a new metric to measure the oxygen saturation within the blood vessels from OCT images. We propose to transmit the lecturer the need to take advantage of the properties within HbO2 and Hb when absorbing light and how that absorption reflected in gray color intensity can be converted as an algorithm to measure the oxygen saturation numerically.
Part of the book: Optical Coherence Tomography