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Updated: Aug 3, 2026

A Simplified Technique for In situ Excision of Cornea and Evisceration of Retinal Tissue from Human Ocular Globe
Published on: June 12, 2012
Reduction of hyperopia associated with manual excision of Salzmann's nodular degeneration
J G Oster1, R F Steinert, R N Hogan
1New England Eye Center, Tufts University School of Medicine, Boston, MA, USA.
Purpose:
Removing central corneal pathology often leads to a hyperopic shift secondary to corneal flattening. A myopic shift, or reduction in hyperopia, would be expected after removal of peripheral corneal pathology with central corneal steepening. This case illustrates the refractive changes induced by Salzmann's nodular degeneration and the myopic shift associated with their excision.
Methods:
A 53-year-old female presented with a slowly progressive increase in hyperopia. Vision in the right eye was 20/40 with a refraction of +10.00 -4.00 x 90 degrees. Vision in the left eye was 20/30 with a refraction of +5.75 -2.00 x 105 degrees. Both corneas exhibited nodular subepithelial opacities in the mid-periphery. A superficial keratectomy was performed on each eye, 1 year apart.
Results:
Twelve days postoperatively, uncorrected visual acuity in the right eye was 20/25, and 20/20 with a refraction of -0.75 -0.50 x 31 degrees, 6 months later. Six days postoperatively, uncorrected visual acuity in the left eye was 20/40, and 20/30 with a refraction of -1.25 D, 1 month later.
Conclusion:
Superficial keratectomy provides a means of restoring the original corneal contour, especially when the pathology is easily dissected from Bowman's layer. The surgeon should investigate the refractive status prior to the development of the nodules and be aware of the possible refractive change upon removal of the pathology.
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