Scleral Expansion Procedure for the Correction of Presbyopia

@article{Kleinmann2006ScleralEP,
  title={Scleral Expansion Procedure for the Correction of Presbyopia},
  author={Guy Kleinmann and Hee Joon Kim and Richard W. Yee},
  journal={International Ophthalmology Clinics},
  year={2006},
  volume={46},
  pages={1-12}
}
Since 1855, the dominant theory for accommodation is that of Hermann von Helmholtz. The Helmholtz mechanism of accommodation states that contraction of the ciliary muscle results in a release of the tension on the zonular fibers allowing the lens to round up and become more convex during accommodation to allow near objects to be brought into focus. Thus, according to Helmholtz, accommodation results in the movement of the equatorial edge of the lens away from the sclera and disaccommodation… 
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References

SHOWING 1-10 OF 45 REFERENCES
The mechanism of accommodation and presbyopia in the primate
TLDR
It is demonstrated that the lens is under increased zonular tension during accommodation and that presbyopia is not due to lens sclerosis or ciliary muscle atrophy, which disprove Helmholtz's longstanding, widely accepted theory of accommodation.
Mechanism of Accommodation
TLDR
No working model lens, based on the Helmholtz’s theory, that has been developed can mimic the properties of the human crystalline lens during accommodation and does not explain the peripheral surface flattening and reduction in spherical aberration that have been reported to occur during accommodation.
In vivo increase of the human lens equatorial diameter during accommodation.
TLDR
The results indicate that the lens equator is under increased zonular tension during accommodation, in contradiction to Helmholtz's widely accepted theory of accommodation.
The mechanism of accommodation in primates.
Presbyopic Surgery
  • R. Schachar
  • Medicine
    International ophthalmology clinics
  • 2002
TLDR
Nonlinear finite element analysis was used to determine the proper design, placement, and important surgical parameters necessary to obtain optimal scleral expansion in order to reverse presbyopia and treat ocular hypertension and primary open-angle glaucoma.
Implantation of scleral expansion band segments for the treatment of presbyopia.
TLDR
It appears that the thickness and uniformity of the scleral belt loop is critical to the proper positioning and efficacy of the SEB segments, and changes in spherical equivalence, axial length, and central keratometry readings were not statistically significant.
The ciliary body in accommodation.
  • R. Fisher
  • Medicine, Biology
    Transactions of the ophthalmological societies of the United Kingdom
  • 1986
TLDR
The ciliary muscle ring contracts about 0.8 mm in radius during maximum accommodation and this change in radius does not significantly alter as the eye ages between 15 and 45 years, but the force of contraction steadily increases over the same age period.
The increasing sclerosis of the human lens with age and its relevance to accommodation and presbyopia
  • H. Pau, J. Kranz
  • Medicine
    Graefe's Archive for Clinical and Experimental Ophthalmology
  • 2004
TLDR
A distinct hardening of the nucleus as opposed to the cortex has been found to occur in lenses as young as 20 years of age, and coincides with the decrease in accommodation range and the onset of presbyopia.
High resolution MRI study of circumlental space in the aging eye.
TLDR
MRI is used to directly detect age related changes in circumlental space of 47 emmetropes and mild myopes and provides unparalleled soft tissue contrast, providing differentiation between muscle and other soft tissue, thus allowing the ciliary muscle to be visualized.
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