Don Davis, MD, Peter Ness, MD, Surekha Maddula, MD, Liliana Werner, MD, PhD, Nick Mamalis, MD

Analysis of Intraoperative Capsular Trauma Induced by a Analysis of Intraoperative Capsular Trauma Induced by a New Single-Use Polymer Irrigation/Aspiration Tip During New Single-Use Polymer Irrigation/Aspiration Tip During

Posterior Capsule PolishingPosterior Capsule Polishing

Don Davis, MD, Peter Ness, MD, Surekha Maddula, Don Davis, MD, Peter Ness, MD, Surekha Maddula, MD, Liliana Werner, MD, PhD, Nick Mamalis, MD 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

BackgroundBackground Posterior capsule rupture is a serious complication of Posterior capsule rupture is a serious complication of

cataract surgery. Roughly one-third of posterior capsule cataract surgery. Roughly one-third of posterior capsule ruptures occur during the irrigation/aspiration stage of ruptures occur during the irrigation/aspiration stage of phacoemulsificationphacoemulsification11. Although posterior capsular polishing . Although posterior capsular polishing does not influence rates of posterior capsule opacificationdoes not influence rates of posterior capsule opacification22, , anterior capsular polishing can decrease rates of anterior anterior capsular polishing can decrease rates of anterior capsule opacification/fibrosiscapsule opacification/fibrosis3 3 and capsular contractionand capsular contraction44. . Because of this effect, some have advocated the use of Because of this effect, some have advocated the use of routine capsular polishing with implantation of multifocal routine capsular polishing with implantation of multifocal and other premium intraocular lenses that are extremely and other premium intraocular lenses that are extremely susceptible to decentration from mild capsular contractionsusceptible to decentration from mild capsular contraction55. . The single-use polymer tip studied here was manufactured The single-use polymer tip studied here was manufactured to decrease posterior capsular trauma during to decrease posterior capsular trauma during irrigation/aspiration and capsular polishing.irrigation/aspiration and capsular polishing.

PurposePurpose To compare the safety and capsular friendliness of a To compare the safety and capsular friendliness of a

new single-use polymer irrigation/aspiration (I/A) port new single-use polymer irrigation/aspiration (I/A) port with a standard metal I/A port in a Miyake cadaver eye with a standard metal I/A port in a Miyake cadaver eye model.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/MethodsMaterial/Methods One eye of each cadaver pair was treated with a standard metal I/A One 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 tip (OD) while the contralateral eye was treated with a single–use polymer I/A tip (OS). polymer I/A tip (OS).

Nine pairs of cadaver eyes were prepared using the Miyake/Apple Nine pairs of cadaver eyes were prepared using the Miyake/Apple technique under open sky for better capsular visualization. technique under open sky for better capsular visualization.

Following capsulorrhexis, and nucleus expression by Following capsulorrhexis, and nucleus expression by hydrodissection, cortex was removed by each respective I/A tip.hydrodissection, cortex was removed by each respective I/A tip.

The aspiration port was then occluded on the posterior capsule and The aspiration port was then occluded on the posterior capsule and swept in several 2-3 mm arcs in order to induce either capsular swept in several 2-3 mm arcs in order to induce either capsular rupture or zonular dehiscence. 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 striae in the striae 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 IIMaterial/Methods II If the posterior capsule/ zonular apparatus remained If the posterior capsule/ zonular apparatus remained

intact, the vacuum was increased in a stepwise fashion intact, the vacuum was increased in a stepwise fashion to a maximum of 600 mmHg.to a maximum of 600 mmHg.

Flow rate and bottle height were fixed. Flow rate and bottle height were fixed. The eyes were assessed by subjectively documenting The eyes were assessed by subjectively documenting

zonular stretching/ dehiscence and objectively zonular stretching/ dehiscence and objectively measuring maximum vacuum measuring maximum vacuum withstood without capsular rupture. withstood without capsular rupture. Due to the small sample Due to the small sample size and combination of two size and combination of two variables into one graded variables into one graded scale (with emphasis on scale (with emphasis on maximum vacuum), the maximum vacuum), the data was analyzed with the data was analyzed with the Wilcoxon Ranked Sum test Wilcoxon Ranked Sum test for non-parametric data. 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. Note within the aspiration port of the I/A tip. Note zonular compromise.zonular compromise.

Eye * Eye * Number Number

Donor Age Donor Age (years)(years)

Time from Time from Enucleation Enucleation

to Studyto StudyTip Tip Test EndpointTest Endpoint§§ CommentsComments

11 6565 2 Days2 Days MetalMetal Posterior capsule tear at 320 mmHgPosterior capsule tear at 320 mmHg --

22 6565 2 Days2 Days PolymerPolymer 4+ zonular stretching at 600 mmHg4+ zonular stretching at 600 mmHg --

33†† 6969 3 Days3 Days -- -- Tear in posterior capsule before testTear in posterior capsule before test

44†† 6969 3 Days3 Days PolymerPolymer 3+ zonular stretching at 600 mmHg3+ zonular stretching at 600 mmHg --

55 5050 3 Days3 Days MetalMetal Posterior capsule tear at 250 mmHgPosterior capsule tear at 250 mmHg Significant zonular dialysis before testSignificant zonular dialysis before test

66 5050 3 Days3 Days PolymerPolymer 3+ zonular stretching at 600 mmHg3+ zonular stretching at 600 mmHg Significant zonular dialysis before testSignificant zonular dialysis before test

77 5656 3 Days3 Days MetalMetal Posterior capsule tear at 600 mmHgPosterior capsule tear at 600 mmHg --

88 5656 3 Days3 Days PolymerPolymer Zonular and posterior capsule tear at 450mmHgZonular and posterior capsule tear at 450mmHg Complete zonular failure during testComplete zonular failure during test

99 6969 2 Days2 Days MetalMetal 3+ zonular stretching at 600 mmHg3+ zonular stretching at 600 mmHg --

1010 6969 2 Days2 Days PolymerPolymer 2+ zonular stretching at 600 mmHg2+ zonular stretching at 600 mmHg --

1111 4646 2 Days2 Days MetalMetal Posterior capsule tear at 320 mmHgPosterior capsule tear at 320 mmHg --

1212 4646 2 Days2 Days PolymerPolymer Posterior capsule tear at 320 mmHgPosterior capsule tear at 320 mmHg --

1313 7878 2 Days2 Days MetalMetal Zonular tear at 320 mmHgZonular tear at 320 mmHg --

1414 7878 2 Days2 Days PolymerPolymer 2+ zonular stretching at 600 mmHg2+ zonular stretching at 600 mmHg --

1515 8686 3 Days3 Days MetalMetal 3+ zonular stretching at 600 mmHg3+ zonular stretching at 600 mmHg --

1616 8686 3 Days3 Days PolymerPolymer 1+ zonular stretching at 600 mmHg1+ zonular stretching at 600 mmHg --

1717 5959 2 Days2 Days MetalMetal Posterior capsule tear at 450 mmHgPosterior capsule tear at 450 mmHg --

1818 5959 2 Days2 Days PolymerPolymer 1+ zonular stretching at 600 mmHg1+ zonular stretching at 600 mmHg --

1919 8686 2 Days2 Days MetalMetal 2+ zonular stretching at 600 mmHg2+ zonular stretching at 600 mmHg --

2020 8686 2 Days2 Days PolymerPolymer 1+ zonular stretching at 600 mmHg1+ 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§§Zonular Stretching from 0-4+ was noted in the study. No zonular dehiscence was noted.Zonular Stretching from 0-4+ was noted in the study. No zonular dehiscence was noted.

Results SummaryResults Summary Ten of 18 eyes were able to tolerate a maximum I/A Ten of 18 eyes were able to tolerate a maximum I/A

vacuum of 600 mmHg (3/9 metal tips and 7/9 polymer vacuum of 600 mmHg (3/9 metal tips and 7/9 polymer tips) without structural compromise (zonular dehiscence or tips) without structural compromise (zonular dehiscence or posterior capsular rupture). posterior capsular rupture).

Metal I/A tips induced 5 Metal I/A tips induced 5 capsular tears and one zonular capsular tears and one zonular dehiscencedehiscence

Polymer I/A tips induced 2 Polymer I/A tips induced 2 capsular tears. capsular tears.

There is a statistically There is a statistically significance difference between significance difference between the metal and polymer tips with the metal and polymer tips with respect to structural respect to structural compromise (p= 0.015). 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.

ConclusionConclusion

Cortical removal and capsular polishing Cortical removal and capsular polishing with the new single-use polymer I/A port is with the new single-use polymer I/A port is a safe alternative to using metal I/A tips a safe alternative to using metal I/A tips and may induce less trauma than metal I/A and may induce less trauma than metal I/A tips. tips.

Utilization of single-use I/A Utilization of single-use I/A tips is also suitable to tips is also suitable to

reduce the likelihood of reduce the likelihood of toxic anterior segment toxic anterior segment syndrome (TASS)syndrome (TASS)6.6. Anterior segment photo of a patient

with TASS – Post-operative Day 1 from phacoemulsification with intraocular lens placement.

ReferencesReferences

1. 1. Gimbel H, Sun R, Ferensowicz M, Penno EA, Kamal A. Intraoperative Gimbel H, Sun R, Ferensowicz M, Penno EA, Kamal A. Intraoperative Management of Posterior Capsule Tears in Phacoemulsification and Management of Posterior Capsule Tears in Phacoemulsification and Intraocular Lens Implantation. Intraocular Lens Implantation. Ophthalmology. Ophthalmology. 2001;108:2186–92. 2001;108:2186–92.

2. Shah SK, Praveen MR, Kaul A, Vasavada AR, Shah GD, Nihalani BR. 2. Shah SK, Praveen MR, Kaul A, Vasavada AR, Shah GD, Nihalani BR. Impact of anterior capsule polishing on anterior capsule opacification Impact of anterior capsule polishing on anterior capsule opacification after cataract surgery: a randomized clinical trial. after cataract surgery: a randomized clinical trial. J Cataract Refract J Cataract Refract SurgSurg. 2010 Feb;36(2):208-14. . 2010 Feb;36(2):208-14.

3. Sacu S, Menapace R, Wirtitsch M, Buehl W, Rainer G, Findl O. Effect of 3. Sacu S, Menapace R, Wirtitsch M, Buehl W, Rainer G, Findl O. Effect of anterior capsule polishing on fibrotic capsule opacification: three-year anterior capsule polishing on fibrotic capsule opacification: three-year results. results. J Cataract Refract Surg.J Cataract Refract Surg. 2004 Nov; 30(11):2322-7. 2004 Nov; 30(11):2322-7.

4. Tadros A, Bhatt UK, Karim A, Zaheer A, and Thomas PW, Removal of lens 4. Tadros A, Bhatt UK, Karim A, Zaheer A, and Thomas PW, Removal of lens epithelial cells and the effect on capsulorhexis size. epithelial cells and the effect on capsulorhexis size. J Cataract Refract J Cataract Refract SurgSurg. 2005 Aug; 31(8):1569–74. . 2005 Aug; 31(8):1569–74.

5. Ossma IL, Galvis A, Vargas LG, Trager MJ, Vagefi MR, McLeod SD. 5. Ossma IL, Galvis A, Vargas LG, Trager MJ, Vagefi MR, McLeod SD. Synchrony dual-optic accommodating intraocular lens. Part 2: pilot Synchrony dual-optic accommodating intraocular lens. Part 2: pilot clinical evaluation. clinical evaluation. J Cataract Refract Surg.J Cataract Refract Surg. 2007 Jan;33(1):47-52. 2007 Jan;33(1):47-52.

6. Mamalis N, Edelhauser HF, Dawson DG, Chew J, LeBoyer RM, Werner L. 6. Mamalis N, Edelhauser HF, Dawson DG, Chew J, LeBoyer RM, Werner L. Toxic Anterior Segment Syndrome. J Cataract Refract Surg. 2006 Toxic Anterior Segment Syndrome. J Cataract Refract Surg. 2006 Feb;32(2):324-33. Feb;32(2):324-33.