The Influence of Corneal Volume in Surgical Planning: Insights for a New Parameter for the Ferrara Ring Nomogram
Leonardo Torquetti, Wagner Gomes Dias
Citation Information :
Torquetti L, Dias WG. The Influence of Corneal Volume in Surgical Planning: Insights for a New Parameter for the Ferrara Ring Nomogram. Int J Kerat Ect Cor Dis 2013; 2 (1):12-15.
To evaluate the corneal volume (CV) before and after Ferrara intrastromal corneal ring segments (ICRS) implantation and its influence in clinical outcomes in keratoconus patients.
Materials and methods
A total of 77 eyes of 42 keratoconus patients consecutively implanted with the Ferrara ICRS were evaluated with a Pentacam (Oculus Optikgerate GmbH). The following parameters were obtained: Anterior corneal asphericity (Q), CV and thinnest corneal thickness (TCT). The inter-relation between Q and CV was evaluated.
Results
In patients with CV inside two standard deviation (SD: 53.51-60.65) of the mean CV, the postoperative asphericity values roughly agreed with expected asphericity values. In patients with CV outside two SD intervals (<53.51 and >60.65) of the mean CV, the postoperative asphericity values did not agreed with expected asphericity values. Corneas with high volumes (>60.65) had less change of asphericity than corneas with low volumes.
Conclusion
The CV is a new parameter, to be better studied, as it seems to be important in ICRS selection. Corneas with high volumes may require more tissue to get flattened and properly reshaped.
How to cite this article
Torquetti L, Ferrara G, Dias WG, Ferrara P. The Influence of Corneal Volume in Surgical Planning: Insights for a New Parameter for the Ferrara Ring Nomogram. Int J Kerat Ect Cor Dis 2013;2(1):12-15.
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