Comparison of scleral tensile strength after transscleral retinal cryopexy, diathermy, and diode laser photocoagulation.
OBJECTIVE
To determine the effect of transscleral diode photocoagulation on the tensile strength of sclera in an experimental rabbit model and to compare it with that of transscleral cryotherapy and diathermy.


METHODS
Twenty-four Dutch-belted rabbits received one of the following three treatment modalities in one eye: (1) transscleral cryotherapy, (2) transscleral diathermy, or (3) transscleral diode laser photocoagulation. The opposite eye served as a paired control. Tensile strength measurements of scleral strips excised from areas of treatment were obtained 6 weeks later.


RESULTS
No statistically significant difference in mean tensile strength was observed between eyes receiving transscleral cryopexy (n = 7) or transscleral diode photocoagulation (n = 8) and their corresponding, paired, control eyes. In contrast, transscleral diathermy reduced mean scleral tensile strength to 26% of that of the paired control eyes (n = 8, P = .0001).


CONCLUSIONS
In this rabbit model, scleral weakening is significant following transscleral diathermy while transscleral cryopexy or transscleral diode photocoagulation produces no significant weakening relative to paired, untreated controls.
Han
D P
DP
Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, USA.
Nash
R W
RW
Blair
J R
JR
O'Brien
W J
WJ
Medina
R R
RR
D000818:Animals; D017679:Cryotherapy; D003972:Diathermy; D005654:Fundus Oculi; D017075:Laser Coagulation; D011817:Rabbits; D012160:Retina / Q000601:surgery*; D012590:Sclera / Q000502:physiology*; D013718:Tensile Strength