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Pathophysiology and Histopathology of Keratoconus

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Keratoconus

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Abstract

From the widely held concept of keratoconus being a bilateral noninflammatory corneal disorder, more insights into its pathophysiology have led us to understand about this disease being multifactorial in origin. The origins of the disease are determined only partly by genetic factors, and it appears to have a complex pathogenesis. The progression and association have been noted with environmental stimuli and coexisting ocular disease such as allergy and several systemic conditions. Histopathologically, changes are noted in all layers of the cornea; however, the hallmark of this condition is stromal thinning. An interplay between proteinase enzymes leading to their upregulation and downregulation of proteinase inhibitors leads to biomechanical corneal instability. Early changes do not affect the vision, and some patients have mild disease with slow or no progression. In others, there appears to be a precipitous progression leading to extremely poor vision if left untreated. In this chapter, we describe the potential pathophysiological mechanisms in keratoconus and discuss in detail the histopathological changes.

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Acknowledgments

  1. 1.

    Dr. Vijayalakshmi Idimadakala for editing help.

  2. 2.

    Mr. Chenchu Naidu and Mr. B Sreedhar for histopathology slides.

Funding Support

Hyderabad Eye Research Foundation, Hyderabad, India.

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Authors and Affiliations

  1. The Cornea Institute, L V Prasad Eye Institute, Hyderabad, Telangana, India

    Somasheila I. Murthy

  2. Ophthalmic Pathology Laboratory, L V Prasad Eye Institute, Hyderabad, Telangana, India

    Dilip K. Mishra

  3. Allen Foster Community Eye Health Research Centre, Gullapalli Pratibha Rao International Centre for Advancement of Rural Eye Care, L V Prasad Eye Institute, Hyderabad, Telangana, India

    Varsha M. Rathi

  4. Indian Health Outcomes, Public Health and Economics (IHOPE) Research Centre, L V Prasad Eye Institute, Hyderabad, Telangana, India

    Varsha M. Rathi

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  1. Somasheila I. Murthy
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Correspondence to Somasheila I. Murthy .

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  1. L V Prasad Eye Institute, Bhubaneswar, Odisha, India

    Sujata Das

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Murthy, S.I., Mishra, D.K., Rathi, V.M. (2022). Pathophysiology and Histopathology of Keratoconus. In: Das, S. (eds) Keratoconus. Springer, Singapore. https://doi.org/10.1007/978-981-19-4262-4_4

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  • DOI: https://doi.org/10.1007/978-981-19-4262-4_4

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