Analysis of Intraoperative Capsular Trauma Induced by a ：术中囊损伤诱导的分析.ppt

Analysis of Intraoperative Capsular Trauma Induced by a New Single-Use Polymer Irrigation/Aspiration Tip During Posterior Capsule Polishing Don Davis, MD, Peter Ness, MD, Surekha Maddula, MD, Liliana Werner, MD, PhD, Nick Mamalis, MD The authors have no financial interest in this productThe authors have no financial interest in this product This project was supported in part by a grant from Alcon and by an unrestricted grant from This project was supported in part by a grant from Alcon and by an unrestricted grant from Research to Prevent Blindness to the Department of Ophthalmology at the University of UtahResearch to Prevent Blindness to the Department of Ophthalmology at the University of Utah Background Posterior capsule rupture is a serious complication of cataract surgery. Roughly one-third of posterior capsule ruptures occur during the irrigation/aspiration stage of phacoemulsification1. Although posterior capsular polishing does not influence rates of posterior capsule opacification2, anterior capsular polishing can decrease rates of anterior capsule opacification/fibrosis3 and capsular contraction4. Because of this effect, some have advocated the use of routine capsular polishing with implantation of multifocal and other premium intraocular lenses that are extremely susceptible to decentration from mild capsular contraction5. The single-use polymer tip studied here was manufactured to decrease posterior capsular trauma during irrigation/aspiration and capsular polishing. Purpose To compare the safety and capsular friendliness of a new single-use polymer irrigation/aspiration (I/A) port with a standard metal I/A port in a Miyake cadaver eye model. A. Photomicrograph (20X) of metal I/A tip used in the A. Photomicrograph (20X) of metal I/A tip used in the Pathology laboratory for research purposes. Note the Pathology laboratory for research purposes. Note the small metal discontinuity on the proximal irrigation port small metal discontinuity on the proximal irrigation port opening that is common to reusable metal I/A tips.opening that is common to reusable metal I/A tips. B. Photomicrograph (20X) of single-use polymer I/A tip B. Photomicrograph (20X) of single-use polymer I/A tip without sleeve. Note the smooth irrigation port opening. without sleeve. Note the smooth irrigation port opening. The tip is distensible with moderate pressure, and the The tip is distensible with moderate pressure, and the aspiration port edges are regular and smooth. aspiration port edges are regular and smooth. BA Material/Methods uOne eye of each cadaver pair was treated with a standard metal I/A tip (OD) while the contralateral eye was treated with a single use polymer I/A tip (OS). uNine pairs of cadaver eyes were prepared using the Miyake/Apple technique under open sky for better capsular visualization. uFollowing capsulorrhexis, and nucleus expression by hydrodissection, cortex was removed by each respective I/A tip. uThe aspiration port was then occluded on the posterior capsule and swept in several 2-3 mm arcs in order to induce either capsular rupture or zonular dehiscence. Miyake view of Miyake view of posterior capsule posterior capsule cleaned with cleaned with metal (A) or metal (A) or silicone polymer silicone polymer tip (B). Note the tip (B). Note the striaestriae in the in the posterior capsule posterior capsule as the aspiration as the aspiration port is occluded port is occluded and swept in 2-and swept in 2- 3mm arcs.3mm arcs. A B Material/Methods II uIf the posterior capsule/ zonular apparatus remained intact, the vacuum was increased in a stepwise fashion to a maximum of 600 mmHg. uFlow rate and bottle height were fixed. uThe eyes were assessed by subjectively documenting zonular stretching/ dehiscence and objectively measuring maximum vacuum withstood without capsular rupture. Due to the small sample size and combination of two variables into one graded scale (with emphasis on maximum vacuum), the data was analyzed with the Wilcoxon Ranked Sum test for non-parametric data. Miyake view of posterior capsule occluded Miyake view of posterior capsule occluded within the aspiration port of the I/A tip. within the aspiration port of the I/A tip. Note Note zonularzonular compromise. compromise. Eye * Number Donor Age (years) Time from Enucleation to Study Tip Test EndpointComments 1652 DaysMetalPosterior capsule tear at 320 mmHg- 2652 DaysPolymer4+ zonular stretching at 600 mmHg- 3693 Days - -Tear in posterior capsule before test 4693 DaysPolymer3+ zonular stretching at 600 mmHg- 5503 DaysMetalPosterior capsule tear at 250 mmHgSignificant zonular dialysis before test 6503 DaysPolymer3+ zonular stretching at 600 mmHgSignificant zonular dialysis before test 7563 DaysMetalPosterior capsule tear at 600 mmHg- 8563 DaysPolymerZonular and posterior capsule tear at 450mmHgComplete zonular failure during test 9692 DaysMetal3+ zonular stretching at 600 mmHg- 10692 DaysPolymer2+ zonular stretching at 600 mmHg- 11462 DaysMetalPosterior capsule tear at 320 mmHg- 12462 DaysPolymerPosterior capsule tear at 320 mmHg- 13782 DaysMetalZonular tear at 320 mmHg- 14782 DaysPolymer2+ zonular stretching at 600 mmHg- 15863 DaysMetal3+ zonular stretching at 600 mmHg- 16863 DaysPolymer1+ zonular stretching at 600 mmHg- 17592 DaysMetalPosterior capsule tear at 450 mmHg- 18592 DaysPolymer1+ zonular stretching at 600 mmHg- 19862 DaysMetal2+ zonular stretching at 600 mmHg- 20862 DaysPolymer1+ zonular stretching at 600 mmHg- Results: Table of Study DataResults: Table of Study Data *Eye Numbers with the same color represent eye pairs*Eye Numbers with the same color represent eye pairs Data was discarded because of tear in posterior capsule prior to study inceptionData was discarded because of tear in posterior capsule prior to study inception ZonularZonular Stretching from 0-4+ was noted in the study. No Stretching from 0-4+ was noted in the study. No zonularzonular dehiscence was noted. dehiscence was noted. Results Summary uTen of 18 eyes were able to tolerate a maximum I/A vacuum of 600 mmHg (3/9 metal tips and 7/9 polymer tips) without structural compromise (zonular dehiscence or posterior capsular rupture). uMetal I/A tips induced 5 capsular tears and one zonular dehiscence uPolymer I/A tips induced 2 capsular tears. uThere is a statistically significance difference between the metal and polymer tips with respect to structural compromise (p= 0.015). Miyake view of posterior capsule after capsular rupture was Miyake view of posterior capsule after capsular rupture was induced by a metal I/A tip.induced by a metal I/A tip. Conclusion uCortical removal and capsular polishing with the new single-use polymer I/A port is a safe alternative to using metal I/A tips and may induce less trauma than metal I/A tips. uUtilization of single-use I/A tips is also suitable to reduce the likelihood of toxic anterior segment syndrome (TASS)6. Anterior segment photo of a patient with TASS Post-operative Day 1 from phacoemulsification with intraocular lens placement. References 1. Gimbel H, Sun R, Ferensowicz M, Penno EA, Kamal A. Intraoperative Management of Posterior Capsule Tears in Phacoemulsification and Intraocular Lens Implantation. Ophthalmology. 2001;108:218692. 2. Shah SK, Praveen MR, Kaul A, Vasavada AR, Shah GD, Nihalani BR. Impact of anterior capsule polishing on anterior capsule opacification after catarac