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Home , Keratoconus, Presbyopia

ALLOGRAFT LENTICULES FOR THE TREATMENT OF A new option in lieu of synthetic corneal inlays.

BY ARTHUR B. CUMMINGS, MB ChB, FCS(SA), MMed(Ophth), FRCS(Edin) TECHNOLOGIES THAT TELL US WHERE IS HEADING ALLOGRAFT INLAYS

onovision, as a strategy for the Kamra (CorneaGen), the Raindrop Those who were happy with these addressing presbyopia, has (ReVision ; no longer available), implants were truly happy with their been used in contact and the Presbia Flexivue Microlens vision, but, despite being meticulous since the 1960s in Ireland. The (Presbia; withdrawn from the market). in selection, I could not refine Wellington Eye Clinic started Of the three, I have had experience the selection process to the point Mimplementing monovision in laser with the Kamra and the Raindrop. where the number of who vision correction shortly after the Both provided reading vision with were unhappy was low enough to introduction of excimer lasers, and, by less loss of UDVA in the reading eye warrant the device’s use. Although I 1998, monovision was in common use than is possible with monovision. never implanted the Presbia inlay, I in our clinic. Over some months of neural adapta- have heard similar comments about Over time, we developed a diagnostic tion, most patients with these inlays that from colleagues. In the workup routine that gave us a very reached a point when they felt as meantime, the Raindrop has been good indication as to whether a patient though there was no loss of UDVA discontinued, and the Presbia has was suitable for monovision or not binocularly but there was a significant been withdrawn from the market. The (http://bit.ly/Cummings0619). With improvement in near vision. Kamra is still available, and surgeons the patient binocularly corrected for When these inlays worked, they gave continue to use it and to report distance (reference = 100%), we added very satisfactory results. The Raindrop satisfactory outcomes. near vision correction in the nondomi- was well tolerated optically but not so nant eye with the auto-phoropter. We well tolerated by the . The Kamra A NEW OPTION used preselected adds (0.00 and -1.00 D was better tolerated by the cornea, but, In my experience, patient for mini-monovision and 0.00 and in my view, too many patients simply satisfaction was higher with the -1.75 D for full monovision) and asked were not happy with their vision. Raindrop than with the Kamra. the patient to score the monovision selection for distance viewing. If the score was above 80%, the odds were high that monovision would work. If the score was below 80%, the odds decreased significantly. One thing was certain, though: When the target for the reading eye was -1.75 D, that eye’s uncorrected distance (UDVA) was typically in the range of 6/48 Snellen, or 20/160 (0.9 logMAR). Despite this poor UDVA in the reading eye, for patients with a good aptitude for monovision, their binocular UDVA was satisfactory, and this was then a small sacrifice for the bonus of greatly increased reading or near vision.

CORNEAL INLAYS In the past decade, several corneal inlays have aimed to provide a modified form of monovision Figure. Postoperative topographies from four patients, obtained within 10 minutes of completion of , presbyopia correction. These include demonstrating centration of the lenticule on anterior segment OCT.

JUNE 2019 | & TODAY 77 To perform PEARL, the donor lenticule is marked at is marked at the donor lenticule To perform PEARL, [email protected] Financial disclosure: Dr. Jacob has a patent pending Director and Chief, Dr. Agarwal’s Refractive and Director and Chief, Dr. Agarwal’s Refractive and Cornea Foundation, and Senior Consultant, Cataract Cornea Foundation, and Senior Consultant, Cataract and Service, Dr. Agarwal’s Eye Hospital, Chennai, India for shaped corneal segments and for the devices and processes used to manufacture them   n n Figure 2. The PEARL lenticule (arrow) is inserted under a Figure 2. The PEARL lenticule (arrow) is inserted under a cap in the patient’s nondominant eye. oxygen and nutrients to pass freely through the This inlays. cornea, unlike some synthetic corneal decreases the risks of cornea, stable ensures a been seen with and melt that have corneal necrosis related inflammation synthetic inlays, and avoids the cornea. into the synthetic material to insertion of a diameter. 1-mm a to trephine a with cut and center its underneath the cornea It is then implanted in centered on a a 120-µm femtosecond laser cap, lenticule coaxially sighted light reflex (Figure 2). The provide eye to implanted in the nondominant is a primer (For vision. intermediate improved near and see http://bit.ly/Jacob0619c). the technique, on binocular In my experience, patients have good but they uncorrected distance and near visual acuity, decrease in some expect be cautioned to do need to uncorrected distance visual acuity in the treated eye. SOOSAN JACOB, MS, FRCS, DNB n Another procedure I have developed is is developed Another procedure I have Once implanted, the PEARL inlay alters the inlay alters the Once implanted, the PEARL PEARL. I have performed CAIRS in a large series of series of a large CAIRS in I have performed cornea’s central radius of curvature and results in and results in of curvature cornea’s central radius a hyperprolate central corneal contour. Made of allows the biocompatible inlay allogenic material, used the technique for all stages of , of keratoconus, the technique for all stages used good results. mild to advanced, with very from (PEARL) refractive lenticule presbyopic allogenic to treat presbyopia implantation. PEARL is designed For this purpose, donor tissue. by using allogenic we used a lenticule of suitable thickness obtained procedure a small-incision lenticule extraction from for performed on a young myopic donor planned to obtain in was easy refractive surgery, as it and sized the absence of other precisely shaped allogenic tissue. within the channels. After the segments are in are in the segments the channels. After within CXL or contact -off accelerated place, –assisted CXL is performed, depending on on a primer the minimum corneal thickness. (For the technique, see http://bit.ly/Jacob0619 and http://bit.ly/Jacob0619b). patients achieve good In my experience, patients. refractive and topographic outcomes, including regularization of the cornea and centralization of the cone, decreased aberrations, and decreased have (Figure 1). I and irregular regular incisions 180º apart. The allogenic tissue is pushed pushed apart. The allogenic tissue is incisions 180º of the channel arc with a in gently from one side side from the other pulled in blunt rod and then hook. The same is repeated Sinskey reverse a with of half arc second segment for the other the with positioned and trimmed the channel. The ends are 9 201 JUNE |

I have developed two novel two novel I have developed allogenic donor cornea treatment one for the therapies, the of keratoconus and one for presbyopia. treatment of Corneal allogenic intrastromal ring intrastromal ring Corneal allogenic In the CAIRS procedure, a femtosecond femtosecond In the CAIRS procedure, a Each allogenic ICRS is obtained from a donor is obtained from a donor allogenic ICRS Each CAIRS. Figure 1. Preoperative (left), postoperative (middle), and topographical difference maps (right) after CAIRS implantation. laser–dissected channel is created with two entry two entry created with laser–dissected channel is 50% corneal depth rather than at 75% to 80%, as with 50% corneal depth rather than at 75% to 80%, as with insertion plane can The shallower synthetic implants. to reshape the cornea, enhance the ability of the ICRS of eyes with more be used in a wider range it can and and/or steepening. severe thinning corneoscleral rim that has been de–endothelialized de–endothelialized that has been corneoscleral rim and de–epithelialized and cut to shape with a double- are bladed trephine (patent pending). Allogenic ICRSs Because they are synthetic ones. more flexible than less likely to more biocompatible than ICRSs, they are can be inserted at or migrated and they be extruded ICRSs avoids the possible complications associated associated complications ICRSs avoids the possible in the cornea, material with implanting synthetic or migration; including implant extrusion, intrusion necrosis; corneal melt; neovascularization; corneal infection. and (ICRSs) are fashioned from human donor corneal corneal donor fashioned from human (ICRSs) are that for similar to implanted in a manner tissue and on whether ICRSs. Depending standard synthetic can or not, CAIRS progressive keratoconus is the cornea. CXL to strengthen the with be combined synthetic of corneal tissue instead Using donor segment (CAIRS) implantation can be performed be performed can segment (CAIRS) implantation this with CXL. For isolation or in combination in segments intrastromal corneal ring procedure, New treatments using allogenic donor tissue are on the horizon. donor tissue are using allogenic treatments New FRCS, DNB BY SOOSAN JACOB, MS, CAIRS FOR KERATOCONUS AND PEARL FOR PRESBYOPIA PEARL AND FOR KERATOCONUS CAIRS CATARACT & REFRACTIVE SURGERY TODAY

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not available in the United States), TABLE. RESULTS FOR READING VISION WITH THE TRANSFORM CORNEAL ALLOGRAFT which allows me to confirm the Preoperative Day 1 Week 1 Month 1 Month 3 centration (Figure) and see the len- 60630 N8 N8 N4 N5 N4 ticule’s position on the OCT cross- section. The MS39 also allows the 60747 N10 N10 N6 N5- N5 measurement of the lenticule thick- 60721 N8 N8 N5 N5 N5 ness using calipers, and it has recorded 60720 N18 N10 N8 N6 N6- thicknesses within 1 µm of the expect- ed thickness of the in vivo lenticule. 60624 N8- N8 N8 N8 N6 Patients are placed on a tapering 60719 N24 N8 N5 N4 N5- dose of topical prednisolone acetate 60716 N14 N4 N5 N4 N5 1% ophthalmic suspension (Pred Forte, 60546 N10 N5 N5 N4 N4 Allergan) over a 4-week period. Even though the look pristine at 60799 N12 N6 N5 N4- N4 the 1-month visit, we continue with 57149 N10 N8 N6 N5 N5 an 8-week taper of flurometholone 60480 N18 N8 N5 N4- N4 ophthalmic suspension 0.1% (FML, Allergan), going from four times per 54436 N14 N8 N6- N5- N5- day down to once per day. 60027 N18 N14 N14- N14 N10 Average N12.2 N7.9 N6.3 (N5.6) N5.6 (N4.9) N6.25 (N5) RESULTS Postoperative data include visits at Average row shows the averages for the entire group and, in parentheses, the averages without the latent hyperopia outlier. day 1, week 1, and months 1, 3, and 6 and will include 12- and 24-month visits Therefore, when an allograft product difference, however, is that the UDVA when patients reach those intervals. that worked on the same principles in the reading eye is in the range I have treated 15 eyes in the as the Raindrop became available, I of 6/12 Snellen (0.5 or 0.3 logMAR) study to date, and my findings are was eager to participate in a European or better rather than the 6/30 to encouraging. Patient satisfaction is clinical trial of the device sponsored by 6/60 Snellen range (0.7 to 1.0 logMAR). higher than with any other corneal the manufacturer. inlay that I have used, and UDVA is The allogenic lenticules (TransForm METHOD significantly better in the reading eye Corneal Allograft, Allotex) are To prepare the lenticule, the than it would be in a monovision obtained from an and package supplied by Allotex is opened, patient with the same reading ability. processed by Allotex into 2.50 D add and the lenticule is bathed in balanced The Table shows the reading vision lenses with a diameter of 2.65 mm and solution to wash away the at the last visit and the trend over time a central thickness of around 29 µm. albumin in which it is stored. In pilot in the eyes of 13 patients who have The lenticules for the ongoing study in studies, when the albumin was not reached 3-month follow-up. All but which I am participating are provided washed from the lenticule, an early one can read at N6 or better; the one by Allotex. inflammatory response could occur. eye that cannot has latent hyperopia The optical effect of the TransForm A LASIK flap is created, normally at of 1.50 D, which is discussed in a subse- inlay produces a controlled induction 100 to 120 µm depth, and the lenticule quent paragraph. All patients are very of negative spherical aberration in the is visually placed over the constricted satisfied with their distance vision. implanted eye, allowing light from . Once the surgeon is satisfied Of the three patients who have distance to enter the eye around the with the centration of the lenticule, passed the 6-month mark, all have the inlay through a large pupil. When the the flap is carefully replaced. I have same level of reading vision that they pupil constricts with convergence and found that waiting a few minutes displayed at the 3-month postopera- attempted , only the allows the lenticule to stick well to the tive visit. There seems to be no further part of the corneal optics that includes cornea, after which there is less chance epithelial remodeling eroding the the lenticule is involved, and there is of the lenticules moving when the flap induced spherical aberration. higher power for reading. is replaced. No inlays have been removed. In my experience, this is equivalent I routinely then acquire a tangential Two patients would like to change the to what one would find with a topography map with the MS39 power of their inlay if a commercial -2.00 D target in a monovision eye. The anterior segment OCT unit (CSO Italia; option becomes available. One of

JUNE 2019 | CATARACT & REFRACTIVE SURGERY TODAY 79 - CRST Europe B, FCS(SA), B, FCS(SA), h ) n din ), FRCS(E phth (O ed My early experience with thewith experience early My [email protected] Financial disclosure: Paid clinical investigator Medical Director, Wellington Eye Clinic Medical Director, Wellington Eye Clinic Associate Chief Medical Editor, (Allotex clinical trial)    ready to go the intraocular route quite route intraocular the go to ready theprefer who patients for and yet inlayan with eye one treating of idea presbyopia- with eyes two than rather IOLs. correcting been has Allograft Corneal TransForm satisfac patient excellent with positive, excitedam I biocompatibility. and tion trialthe continuing of prospect the at haspause mandatory the after now completed. been ARTHUR B. CUMMINGS, MB C MM n n n n - The two patients who are slightlyare who patients two The eyes20 after paused was study The were enrolled to allow determina allow to enrolled were endpointsefficacy and safety of tion mark.postoperative 1-month the at haseyes 120 next the of Enrollment encouragingour Given started. now allograft that believe I results, early successfuland viable a be may inlays managementthe to solution corneal notare who patients for presbyopia of tightened to a range of plano to 0.75 D 0.75 to plano of range a to tightened . cycloplegic that, reported overcorrected or under- theremove to was option only the if Theis. as it keep would both lenticule, highin results replaced be can it that fact on confidence preoperative of degrees patient. and surgeon both of parts the MORE TO COME - 9 201 JUNE |

For the study, there is only oneonly is there study, the For The other patient was -0.50 D prior D -0.50 was patient other The again, a simple excimer laser ablationlaser excimer simple a again, replace lenticule as time same the at issue. refractive any resolve could ment D), (2.50 available power lenticule beenhave criteria inclusion the and performed on the flap.the on performed muchtoo has now and surgery to mustpatient (The power. reading Thisclose.) too materials reading hold or, lenticule, weaker a requires patient (1.50 D) to allow use of the inlay, but inlay, the of use allow to D) (1.50 becould vision reading patient’s this inlay.powerful more a with improved performed be could LASIK better, Even foraiming and flap the lifting by thereplacing then and becould PRK Alternatively, lenticule. these patients had latent hyperopia latent had patients these enough low was believed we that CATARACT & REFRACTIVE SURGERY TODAY

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