No abstract

To investigate the influence of elevated intraocular pressure on the posterior chamber-anterior hyaloid membrane (PC-AHM) barrier during cataract operations in ex vivo porcine eyes. Methods: A pressure transducer was connected to porcine eye anterior chambers (ACs). In experiment 1, ACs were perfused for 20 seconds with balanced salt solution containing 1.0-µm fluorescein beads (10 eyes per bottle height: 45, 85, 145, and 285 cm). In experiment 2, 5 ophthalmic viscosurgical devices with different molecular weights and sodium hyaluronate concentrations were infused into the ACs (20 eyes per ophthalmic viscosurgical device). After continuous curvilinear capsulorrhexis, hydrodissection was performed. After both experiments, PC-AHM barrier staining was evaluated through the Miyake-Apple view. Results: Types of fluorescein staining patterns were classified as AC, zonule of Zinn, AHM, AHM tear, and ruptured capsule. In experiment 1, plateau intraocular pressure and staining type were positively correlated (Spearman rank correlation; r=0.703, P Ͻ.001). In experiment 2, mean peak intraocular pressure was significantly greater in the ruptured capsule-type eyes than in the AC-, zonule of Zinn-, AHM (P Ͻ .001), or AHMtear-(P=.02) type eyes, as well as in the AHM-and AHMtear-type eyes compared with the AC and zonule of Zinn type eyes (P Ͻ .001). Intraocular pressure was significantly higher in eyes infused with ophthalmic viscosurgical devices with a higher molecular weight or sodium hyaluronate concentration (P Ͻ.05). Conclusions: Stress on the PC-AHM barrier increases as intraocular pressure increases. Ophthalmic viscosurgical devices with a higher molecular weight or sodium hyaluronate concentration might induce increased IOP during cataract operations. Clinical Relevance: To maintain normal PC-AHM barrier function, excessive intraocular pressure should be avoided during cataract operations.

The LVFX IC was effective at suppressing endophthalmitis caused by E. faecalis in eyes with a PCR.

BackgroundTo determine if a method for irrigation and aspiration (I/A) during cataract surgery provides effective removal of ophthalmic viscoelastic device (OVD).MethodsJapanese porcine eyes were used to evaluate I/A performance with Technique 1 (the I/A tip placed on the center of the anterior surface of the IOL), Technique 2 (the I/A tip alternately pressed near the edge of the IOL optic anterior surface on one side and then the other to tilt the IOL back and forth), and Technique 3 (the I/A tip inserted behind the IOL optic, between it and the posterior capsule). Techniques 1 and 2 were compared using the Miyake-Apple posterior view video technique to visualize the flow of irrigation fluid containing triamcinolone acetonide particles behind the IOL. To check the efficacy of OVD removal from behind the IOL for of all three I/A techniques, OVD with fluorescein beads were inserted inside the lens capsule before implantation of the IOL. After each I/A technique, eyes were prepared for Miyake–Apple viewing and pictures of the lens capsule were taken using fluorescent microscopy. Residual fluorescein beads in the capsular bag were analyzed.ResultsTechnique 1 resulted in a straight flow of fluid behind the IOL, while Technique 2 resulted in a vortex flow. The average amount of OVD retained inside the capsule after using Technique 2 or 3 was significantly lower than after using Technique 1 (p <0.0001).ConclusionsTechnique 2 proved to remove more effectively fluorescein bead-labelled OVD under the IOL than Technique 1.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2415-14-129) contains supplementary material, which is available to authorized users.