Applied Anatomy of the Corneal Stroma

  • Harminder Singh DuaEmail author
  • Dalia G. Said
Part of the Essentials in Ophthalmology book series (ESSENTIALS)


The corneal stroma is made of Bowman’s layer (BL) anteriorly; the stromal lamellae, which form the bulk of its thickness, centrally; and the pre-Descemet’s layer (Dua’s layer) (PDL) which lines the posterior stroma, lying just anterior to Descemet’s membrane. The BL and PDL are believed to be derived from the embryonic primary stroma, and the central lamellae are derived from collagen laid down by the third wave of migration of neural crest cells. The BL is an acellular, homogenous layer of uniform thickness, made primarily of type I and type III collagen. It is present in human corneas but not in all mammals. Its exact function is unknown. When destroyed, like after laser corneal surgery, it does not regenerate. The bulk of the stroma is made of orthogonally arranged lamellae of predominantly type I collagen. These lamellae run at right angles but are more compact with some obliquely oriented fibres, anteriorly. At the periphery near the limbus, they run a tangential or circular course. The lamellae are more ‘intertwined’ at the periphery than in the centre of the cornea. The predominant cell of the stroma is the keratocyte. Keratocytes lie in between lamellae and have long processes that extend from the cell bodies and make connection with corresponding processes from neighbouring cells. They lay down collagen and, following injury, can transform to fibroblasts and myofibroblasts. Posteriorly there is a distinct cleavage plane between the stroma and the PDL, which is exploited in lamellar surgery and also becomes manifest in posterior cornea pathology. The PDL is largely acellular, is made of 5–8 compactly arranged thin lamellae of type III and type VI collagen and a high concentration of elastin. It is impervious to air and at the periphery has single or clusters of microscopic fenestrations all along the circumference. The collagen lamellae disassociate and open out along the periphery to continue as the collagen/elastin core of the trabecular meshwork.


Bowman’s layer Keratocytes Pre-Descemet’s layer Dua’s layer Corneal biometrics 


Declaration of Interest

None of the authors have any conflict of interest related to the subject matter and content of the chapter. HS Dua is Consultant for Dompe, Santen, Thea and Shire. He has shares in NuVision BioTherapeutics and GlaxoSmithKline. No human or animal studies were carried out by the authors for this chapter.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Academic Section of Ophthalmology, Division of Clinical NeuroscienceUniversity of NottinghamNottinghamUK
  2. 2.Department of OphthalmologyQueens Medical Centre, University Hospitals NHS TrustNottinghamUK
  3. 3.Research Institute of Ophthalmology (RIO)CairoEgypt

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