**Author details**

Jeffery G. Grigsby1,2,3 and Andrew T.C. Tsin<sup>4</sup> \*

\*Address all correspondence to: andrew.tsin@utsa.edu

1 Vision Health Specialties, Midland, Texas, USA

2 College of Optometry, University of Houston, Houston, Texas, USA

3 Texas Tech University Health Science Center, Midland, Texas, USA

4 Department of Biomedical Sciences, University of Texas Rio Grande Valley, School of Medicine, Edinburg, Texas, USA

**Early Events in Diabetic Retinopathy**

cially for those whose control of systemic conditions is less than optimal. Genetics obviously also plays a role, but this is still not clearly understood. In this book, we review areas under investigation to help us better screen, predict, and understand some mechanisms relating to development of DR. Progress has been made, but much work remains because current treatments are available only near the endpoints of DR. Innovative and effective advances allowing the early detection and intervention of DR are especially relevant and urgently needed.

\*

4 Department of Biomedical Sciences, University of Texas Rio Grande Valley, School of

**Author details**

Jeffery G. Grigsby1,2,3 and Andrew T.C. Tsin<sup>4</sup>

6 Early Events in Diabetic Retinopathy and Intervention Strategies

Medicine, Edinburg, Texas, USA

\*Address all correspondence to: andrew.tsin@utsa.edu

2 College of Optometry, University of Houston, Houston, Texas, USA 3 Texas Tech University Health Science Center, Midland, Texas, USA

1 Vision Health Specialties, Midland, Texas, USA

**Chapter 2**

**Provisional chapter**

**Potential Imaging Biomarkers in the Development and**

**Potential Imaging Biomarkers in the Development and** 

Diabetic retinopathy (DR) is the most prevalent microvascular complication of diabetes and a leading cause of preventable blindness in the working-age population. However, due to a lack of suitable biomarkers, its prediction in asymptomatic patients is insufficient. Currently, DR is diagnosed at a stage when typical morphologic lesions become fundoscopically visible. Yet, chronically elevated blood glucose levels lead to characteristic alterations in retinal vessel caliber, blood flow, oxygen saturation, and the capillary network, which precede DR lesions. Furthermore, emerging evidence suggests that retinal neurodegenerative changes occur early in diabetes, initiating a disintegration of the retinal neurovascular unit prior to the appearance of microvasculopathy in DR. This chapter will discuss recent research achievements toward understanding the complexities of DR pathophysiology. It will focus on the nomination of potential imaging biomarkers for the prediction of DR development and progression using innovative structural, functional, and metabolic imaging techniques, including optical coherence tomography angiography (OCTA), retinal oximetry, ultra-wide field FA, and corneal confocal microscopy (CCM). Validation of these biomarkers would allow the identification of patients at high risk of developing DR and might initiate a swift move to early diagnosis and individualized care.

**Keywords:** diabetic retinopathy, biomarker, retinal blood flow, retinal oxygen saturation, retinal neurodegeneration, corneal confocal microscopy, ultra-wide field

The prevalence of diabetes mellitus is increasing worldwide. The International Diabetes Federation estimated that 415 million people had diabetes in 2015, 90% of whom were

imaging, disorganization of the inner retinal layers, imaging, OCT, OCTA

**1. Introduction: the role of biomarkers in disease prediction**

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

DOI: 10.5772/intechopen.71747

**Progression of Diabetic Retinopathy**

**Progression of Diabetic Retinopathy**

Julia Hafner, Sonja Karst and Ursula Schmidt-Erfurth

Julia Hafner, Sonja Karst and Ursula Schmidt-ErfurthAdditional information is available at the end of the chapter

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71747

**Abstract**

#### **Potential Imaging Biomarkers in the Development and Progression of Diabetic Retinopathy Potential Imaging Biomarkers in the Development and Progression of Diabetic Retinopathy**

DOI: 10.5772/intechopen.71747

Julia Hafner, Sonja Karst and Ursula Schmidt-Erfurth Julia Hafner, Sonja Karst and Ursula Schmidt-Erfurth

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71747

#### **Abstract**

Diabetic retinopathy (DR) is the most prevalent microvascular complication of diabetes and a leading cause of preventable blindness in the working-age population. However, due to a lack of suitable biomarkers, its prediction in asymptomatic patients is insufficient. Currently, DR is diagnosed at a stage when typical morphologic lesions become fundoscopically visible. Yet, chronically elevated blood glucose levels lead to characteristic alterations in retinal vessel caliber, blood flow, oxygen saturation, and the capillary network, which precede DR lesions. Furthermore, emerging evidence suggests that retinal neurodegenerative changes occur early in diabetes, initiating a disintegration of the retinal neurovascular unit prior to the appearance of microvasculopathy in DR. This chapter will discuss recent research achievements toward understanding the complexities of DR pathophysiology. It will focus on the nomination of potential imaging biomarkers for the prediction of DR development and progression using innovative structural, functional, and metabolic imaging techniques, including optical coherence tomography angiography (OCTA), retinal oximetry, ultra-wide field FA, and corneal confocal microscopy (CCM). Validation of these biomarkers would allow the identification of patients at high risk of developing DR and might initiate a swift move to early diagnosis and individualized care.

**Keywords:** diabetic retinopathy, biomarker, retinal blood flow, retinal oxygen saturation, retinal neurodegeneration, corneal confocal microscopy, ultra-wide field imaging, disorganization of the inner retinal layers, imaging, OCT, OCTA
