International Ophthalmology

, Volume 38, Issue 6, pp 2627–2633 | Cite as

A virtual model to assess maximum treatable area in LASIK and feasibility of a temporal hinge

  • Ameya Rajas Deepak IngawaleEmail author
  • Jagadeesh K. Reddy
  • K. S. Siddharthan
  • Neeraj Apoorva Shah
  • Shadab Rafat Khan
Case Report



To generate virtual models using different hinge locations and to investigate the advantages of a temporal hinge to a superior in LASIK.


The study design was cross sectional. An image processing software was used to construct virtual LASIK models of 56 slit lamp photos of eyes. For a given hinge location and width, the largest flap diameter and maximum treatable stromal bed area were calculated, comparing temporal hinge to superior.


Temporal hinge allowed a greater flap diameter than superior and thus a greater treatment zone area for a given hinge width. A temporal hinge allowed a greater hinge width than a superior hinge for a given treatment zone area.


We provide a rational basis for a mechanically stable temporal hinge. Moreover, we provide a method to pre-operative model flap size and hinge location, using a slit lamp camera and an image editing software.


Compliance with ethical standards

Conflict of interest

All authors certify that they have no affiliations with or involvement in any organisation or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript.


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Copyright information

© Springer Science+Business Media B.V. 2017

Authors and Affiliations

  1. 1.Cornea and Refractive SurgerySankara Eye Care InstitutionsCoimbatoreIndia

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