Magnifying prismatic lenses for vitrectomy.
OBJECTIVE
Viewing the fundus at higher magnification during vitrectomy makes surgical procedures much safer; however, the scope of magnification of the peripheral fundus has been limited. For better visualization of the periphery of the fundus, we have developed two new contact lenses called magnifying prismatic lenses.


METHODS
The magnifying 15 degrees and 30 degrees prismatic lenses are made of a glass with a high index of refraction (n = 1.883). The lenses have a convex upper surface to provide a magnified view of the peripheral fundus.


RESULTS
These magnifying 15 degrees and 30 degrees prismatic lenses provide an approximately 2x magnified view of the peripheral fundus. They also provide a more extensive view of the peripheral fundus than a regular (plano-concave) prismatic lens when the eye is tilted.


CONCLUSIONS
The magnifying prismatic lenses are useful for viewing into the peripheral fundus with higher magnification.
Ohji
M
M
Department of Ophthalmology, Osaka University Medical School, Osaka, Japan.
Futamura
H
H
Sanger
D
D
Nakata
K
K
Hayashi
A
A
Kusaka
S
S
Tano
Y
Y
D005654:Fundus Oculi; D006801:Humans; D007909:Lenses; D055095:Optics and Photonics; D014821:Vitrectomy