Abstract
Purpose: :
To evaluate and visualize anterior chamber maintenance by Scheimpflug photography for the new Healon Ophthalmic Viscosurgical Systems (Healon D+GV and Healon D+H, Advanced Medical Optics Inc.) along with DuoVisc (Viscoat + Provisc, Alcon Inc.) during simulated cataract surgery.
Methods: :
Cataract surgery was simulated ex vivo in porcine eyes, using dual injection of OVDs according to the softshell technique. Dispersive and cohesive OVDs were stained with fluorescein, 8 µg/ml and 3 µg/ml respectively, for detection purposes. Standard Healon delivery system was used for all samples. Anterior chamber depth (ACD) was measured before surgery, after injection of dispersive OVD, after injection of cohesive OVD, and after phacoemulsification (Sovereign® Compact system, AMO) as monitored by Scheimpflug photographs (Pentacam HR, Oculus) and presented as relative ACD of each eye before surgery. Results were grouped according to product used at each step of the surgical procedure. The non-parametric Kruskal-Wallis test was used to evaluate differences between the medians of relative ACDs of the products at each step of the surgical procedure.
Results: :
Scheimpflug photographs visualizes in a novel way the softshell OVD distribution within the anterior chamber, 75-80% of ACD was filled with cohesive OVD covered by a smooth layer of ~0.7 mm dispersive OVD along cornea. After phacoemulsification the contribution of OVD to ACDs were (median values) 36% (Healon D+GV, n=10), 28% (Healon D+H, n=9), and 4.7% (DuoVisc, n=14). The Kruskal-Wallis test showed significant variation between these medians (P<0.05). The medians of relative ACDs after phacoemulsification did not vary significantly. Before phacoemulsification no significant variation between the three groups was observed regarding relative ACDs or for individual OVD contribution to ACD.
Conclusions: :
The new Healon Ophthalmic Viscosurgical Systems (Healon D+GV and Healon D+H) are equivalent to DuoVisc in creating and maintaining the anterior chamber depth during simulated cataract surgery including the phacoemulsification step.
Keywords: small incision cataract surgery • imaging/image analysis: non-clinical • anterior chamber