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Purpose: To validate the ability of theranostic imaging biomarkers in assessing corneal cross-linking (CXL) efficacy in flattening the maximum keratometry (K max ) index., Design: Prospective, randomized, multicenter, masked clinical trial (ClinicalTrails.gov identifier, NCT05457647)., Participants: Fifty patients with progressive keratoconus., Intervention: Participants were stratified to undergo epithelium-off (25 eyes) and epithelium-on (25 eyes) CXL protocols using an ultraviolet A (UV-A) medical device with theranostic software. The device controlled UV-A light both for performing CXL and assessing the corneal riboflavin concentration (riboflavin score) and treatment effect (theranostic score). A 0.22% riboflavin formulation was applied onto the cornea for 15 minutes and 20 minutes in epithelium-off and epithelium-on protocols, respectively. All eyes underwent 9 minutes of UV-A irradiance at 10 mW/cm 2 ., Main Outcome Measures: The primary outcome measure was validation of the combined use of theranostic imaging biomarkers through measurement of their accuracy (proportion of correctly classified eyes) and precision (positive predictive value) to classify eyes correctly and predict a K max flattening at 1 year after CXL. Other outcome measures included change in K max , endothelial cell density, uncorrected and corrected distance visual acuity, manifest spherical equivalent refraction and central corneal thickness 1 year after CXL., Results: Accuracy and precision of the theranostic imaging biomarkers in predicting eyes that had >0.1 diopter (D) of K max flattening at 1 year were 91% and 95%, respectively. The K max value significantly flattened by a median of -1.3 D (IQR, -2.11 to -0.49 D; P < 0.001); both the uncorrected and corrected distance visual acuity improved by a median of -0.1 logarithm of the minimum angle of resolution (logMAR; IQR, -0.3 to 0.0 logMAR [P < 0.001] and -0.2 to 0.0 logMAR [P < 0.001], respectively). No significant changes in endothelial cell density (P = 0.33) or central corneal thickness (P = 0.07) were noted 1 year after surgery., Conclusions: The study demonstrated the efficacy of integrating theranostics in a UV-A medical device for the precise and predictive treatment of keratoconus with epithelium-off and epithelium-on CXL protocols. Concentration of riboflavin and its UV-A light mediated photoactivation in the cornea are the primary factors determining CXL efficacy., Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article., (Copyright © 2024 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the outcomes of a 9-mm deep anterior lamellar keratoplasty (DALK) with removal of the deep stroma limited to the central 6-mm optical zone., Design: Prospective, noncomparative, interventional case series., Participants: A total of 80 consecutive keratoconic eyes without deep stromal scarring, with at least 1 postoperative examination 1 month after complete suture removal., Intervention: A standardized DALK was performed, including (1) deep trephination of the recipient bed 450 to 550 μm in depth and 9 mm in diameter; (2) pneumatic dissection; (3) debulking of approximately 80% of the anterior stroma; (4) removal of the deep stroma (bubble roof) from a central 6-mm optical zone; and (5) transplantation of a 9-mm anterior corneal lamella cut by microkeratome-assisted dissection (400-μm head) and sutured with a double running 10-0 nylon suture., Main Outcome Measures: Success rate and type of pneumatic dissection obtained; best spectacle-corrected visual acuity (BSCVA), refractive astigmatism (RA), and topographic astigmatism (TA), central corneal thickness (CCT) and endothelial cell density 12 months postoperatively; and intraoperative and postoperative complications., Results: Pneumatic dissection created a "big bubble" in 67 of 80 eyes (83.7%), all of them but 1 (1.5%) being of type 1 according to the classification by Dua et al. After complete suture removal, BSCVA averaged 0.09±0.72 logarithm of the minimum angle of resolution (logMAR) and was ≥20/20 in 28 eyes (35%), ≥20/25 in 54 eyes (67.5%), and ≥20/40 in 76 eyes (95%); RA averaged 3.10±1.30 diopters (D), with 73 eyes (91%) within 4.5 D and none above 6 D; regular TA was detected in 72 eyes (90%); mean CCT was 492±62.10 μm; postoperative endothelial cell density averaged 2026±397cells/mm 2 with a mean cell loss of 11.2%. Intraoperative complications included loss of suction (n = 1) and perforation (n = 4). No conversion to penetrating keratoplasty was necessary. After surgery, double anterior chamber was observed in 2 cases (2.5%), both managed successfully by air filling of the anterior chamber. Stromal rejection was observed in 6 eyes (7.5%) and was reversed with topical steroids in all cases., Conclusions: In keratoconic eyes without deep stromal scars, the combination of a graft larger than conventional ones with limited removal of deep stroma can improve visual and refractive outcomes of DALK, while minimizing the rate of complications., (Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the feasibility and outcomes of contact lens-assisted bimanual pull-through delivery of Descemet membrane endothelial keratoplasty (DMEK) tissue trifolded with the endothelium inward., Design: Prospective, noncomparative, interventional case series., Participants: Forty-two consecutive eyes of 42 patients with Fuchs endothelial dystrophy with or without cataract., Intervention: Standardized DMEK was performed as a single procedure (n = 9) or in combination with phacoemulsification and implantation of a posterior chamber intraocular lens (n = 33) using prestripped donor tissue punched to a diameter of 8.25 mm and then trifolded with the endothelium in. Using a sterile soft contact lens as scaffold, the tissue was loaded in this configuration into a disposable cartridge and delivered into the anterior chamber under continuous irrigation using a bimanual pull-through technique to facilitate spontaneous proper unfolding., Main Outcome Measures: Surgical time, intraoperative and postoperative complications, visual acuity 3 and 6 months after surgery, and endothelial cell loss 6 months after surgery., Results: Surgery was uneventful in all cases and the time required for the DMEK procedure (from Descemet scoring until final air filling) never exceeded 20 minutes (average, 17.1±1.6 minutes). The only complication observed after surgery was graft detachment (10 of 42 eyes [23.8%]), successfully managed in all cases by single rebubbling within 6 days from surgery. In all eyes with a minimum postoperative follow-up of 6 months (n = 20), best spectacle-corrected visual acuity was 20/25 or better and the average endothelial cell density (±standard deviation) was 2363.8±82.7 cells/mm(2) (range, 2258-2490 cells/mm(2)). The cell loss calculated as a percentage of the preoperative value determined at the eye bank (range, 2500-2700 cells/mm(2)) was 9.9±2.1% (range, 4.1%-11.9%)., Conclusions: Delivering DMEK tissue, trifolded with the endothelium inward, reduces surgical trauma to donor cells and facilitates spontaneous unfolding, thus minimizing surgical time., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the outcomes and graft survival rates after ultrathin (UT) Descemet's stripping automated endothelial keratoplasty (DSAEK) using the microkeratome-assisted double-pass technique., Design: Prospective, consecutive, interventional case series., Participants: Patients with endothelial decompensation of various causes (Fuchs endothelial dystrophy, pseudophakic or aphakic bullous keratopathy, failed previous graft, herpetic endotheliitis, or buphthalmus; n = 285 grafts)., Intervention: Donor preparation was performed using the microkeratome-assisted double-pass technique. Stripping of the Descemet's membrane was performed under air and the graft was delivered into the anterior chamber using the pull-through technique through a 3-mm clear-cornea incision using a modified Busin glide., Main Outcome Measures: Best spectacle-corrected visual acuity (BSCVA), manifest refraction, endothelial cell density, and graft thickness (GT)., Results: Excluding all eyes with pre-existing ocular comorbidities, mean BSCVA at 3, 6, 12, and 24 months was 0.16, 0.11, 0.08, and 0.04 logarithm of the minimum angle of resolution units, respectively. The percentage of patients achieving BSCVA of 20/20 or better at 3, 6, 12, and 24 months was 12.3%, 26.3%, 39.5%, and 48.8%, respectively. A statistically significant (P < 0.0001) hyperopic shift of 0.78 ± 0.59 diopters (D; range, -0.75 to 1.75 D) was found at 1 year. The endothelial cell loss at 3, 6, 12, and 24 months was 29.8 ± 14.3%, 33 ± 15.5%, 35.6 ± 14.1%, and 36.6 ± 16.0%, respectively. The mean central GT recorded 3 months after surgery was 78.28 ± 28.89 μm. Complications included microkeratome failure to achieve perfect dissection in 21 donor tissues (7.2%), with 6 (2.1%) being discarded; total graft detachment in 11 cases (3.9%); primary failure in 4 cases (1.4%); and secondary failure in 4 additional cases (1.4%). Kaplan-Meier cumulative probability of a rejection episode at 3, 6, 12, and 24 months was 0%, 0.4%, 2.4%, and 3.3%, respectively., Conclusions: The visual outcomes of UT DSAEK are comparable with those published for Descemet's membrane endothelial keratoplasty and better than those reported after DSAEK in terms of both speed of visual recovery and percentage of patients with 20/20 final visual acuity. However, unlike with Descemet's membrane endothelial keratoplasty, preparation and delivery of donor tissue are neither difficult nor time consuming. Complications of UT DSAEK do not differ substantially from those recorded with standard DSAEK but are much less frequent than those reported after Descemet's membrane endothelial keratoplasty., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., (Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the feasibility of intraoperative anterior segment (AS) optical coherence tomography (OCT) for quantification of the corneal depth reached with the dissecting cannula used for deep anterior lamellar keratoplasty, as well as its correlation with the success rate of big-bubble formation., Design: Retrospective, noncomparative, interventional case series., Participants: One hundred consecutive keratoconus patients., Intervention: Deep anterior lamellar keratoplasty was performed using the big-bubble technique. During surgery, the cannula used for pneumatic dissection was inserted into the peripheral stroma and advanced as deep and far toward the center as believed adequate by the surgeon. Then, after retracting the cannula, AS OCT was performed. The cannula was placed back in position and creation of the big bubble was attempted., Main Outcome Measures: Stromal depth reached with the cannula tip, success rate in achieving big-bubble formation, and complication rate., Results: Bubble formation was obtained in 70 of 100 eyes (70%). In all remaining eyes, the procedure was completed by manual deep lamellar dissection. The average depth reached by the cannula tip was 104.3±34.1 μm from the internal corneal surface; the mean value recorded in cases of successful big-bubble formation (90.4±27.7 μm) was statistically lower than that measured in failed procedures (136.7±24.2 μm). In 1 case, corneal perforation occurred during the insertion of the cannula and required conversion to penetrating keratoplasty (PK). In 8 eyes, small microperforations occurred during stromal excision but could be managed conservatively, avoiding conversion to PK. In 2 advanced cones, an incomplete bubble formation was obtained, necessitating manual peripheral stromal removal., Conclusions: Successful big-bubble formation can be anticipated if pneumatic dissection is attempted at a sufficiently deep level. Although an ideal depth could not be defined, AS OCT allows objective evaluation of the depth reached by the cannula tip used for pneumatic dissection. The AS OCT findings may confirm the decision to proceed with air injection. It is possible that cannula repositioning based on the AS OCT depth may improve the success rate for big-bubble formation., (Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the use of a peripheral stromal support to facilitate and improve the outcomes of Descemet's membrane endothelial keratoplasty (DMEK)., Design: Prospective case series., Participants: Ten patients with Fuchs' endothelial dystrophy., Intervention: Pneumatic dissection was used to detach the central part of the Descemet's membrane and endothelium from the deep stroma. Endothelial grafts including a peripheral stromal support were obtained by eccentric punching of donor tissue and used to perform DMEK surgery in 10 patients., Main Outcome Measures: Operative time, graft attachment rate, best spectacle-corrected visual acuity (BSCVA), endothelial cell loss, refraction, and complications., Results: In all cases the surgical time was ≤ 1 hour. The postoperative course was uneventful in all but 2 cases, which required rebubbling owing to early graft detachment. Final attachment rate was 100%. The average follow-up was 8.4 months (range, 6-12). Postoperative BSCVA was ≥ 20/40 in all cases and no substantial change in refraction was recorded. Postoperative endothelial cell loss averaged 24.1% (range, 8%-34.9%)., Conclusions: Stromal support facilitates surgery, reduces complications, and appears to maintain the favorable outcomes of DMEK., (Copyright © 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the feasibility of pneumatic dissection of donor endothelium and the effect of 7 days of storage in tissue culture medium on the endothelial cell count., Design: Experimental study., Participants: We used 20 human donor corneoscleral tissues deemed unsuitable for transplantation., Intervention: Donor corneas were mounted on an artificial anterior chamber and the anterior stroma removed with a 300-micron microkeratome head. Air was injected into the residual donor tissue with a 30-G needle from the endothelial side to detach Descemet's membrane. The "bubble" was expanded as far as possible into the periphery. A silicone weight was attached to the scleral ring and the prepared tissue was stored in tissue culture medium for 7 days., Main Outcome Measures: Complete detachment of Descemet's membrane, size of detachment, pre- and post-storage endothelial cell counts., Results: Complete detachment of Descemet's membrane was achieved in 19 of 20 (95%) cases. In 12 (60%) cases, this was achieved with a single injection; 7 (35%) cases required repeat injections. In 1 case, Descemet's membrane could not be detached despite repeat air injections. The average size of detachment was 8.11+/-2.0 mm. Endothelial cell loss after 7 days of tissue culture medium storage was 4.44+/-4.3%., Conclusions: Descemet's membrane and endothelium can be separated from the overlying stroma with a simple technique using air dissection. An adequate size of graft tissue is obtained without the need to manually handle the tissue. The technique allows storage of the tissue in tissue culture medium with low endothelial cell loss., (Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate changes in posterior corneal curvature as a possible cause of the hyperopic refractive shift observed after Descemet's stripping automated endothelial keratoplasty (DSAEK)., Design: Prospective, noncomparative, interventional case series., Participants: Thirty-four eyes of 29 patients with Fuchs' endothelial dystrophy or pseudophakic bullous keratopathy., Methods: A standard DSAEK procedure was performed in 34 eyes using the pull-through technique for graft delivery. When cataract was present (n = 7), phacoemulsification with posterior chamber intraocular lens implantation was combined. Each eye underwent Pentacam (Oculus, Wetzlar, Germany) evaluation 1, 3, and 12 months after surgery. Corneal graft thickness was calculated on Scheimpflug scans at 9 locations (1 central, 4 peripheral, and 4 mid peripheral). The mean radius of posterior corneal curvature (Rm) was recorded. At each postoperative examination time, manifest refraction was determined and compared with pre-DSAEK values in simple procedures or with intended postoperative refraction, if cataract surgery had been performed., Main Outcome Measures: Manifest refraction, Rm, and corneal graft thickness at 1, 3, and 12 months after surgery., Results: The mean+/-standard deviation posterior corneal curvature was 6.5+/-0.56 mm before surgery and varied from 5.52+/-0.39 mm 1 month after surgery to 5.83+/-0.37 mm at 3 months after surgery and 5.92+/-0.35 mm at 12 months after surgery. The grafts were significantly thicker in the periphery and mid periphery than in the center at all examination times. Thickening diminished significantly over time at all locations. The average reduction of corneal thickness was higher at the edges (91.5 microm) than in the mid periphery (38.3 microm) or in the center (24.2 microm). The average postoperative spherical equivalent+/-standard deviation changed from -0.31+/-2.35 diopters (D) before surgery to 1.03+/-2.21 D 1 month after surgery, 0.61+/-2.07 D 3 months after surgery, and +0.31+/-2.03 D 12 months after surgery., Conclusions: The difference in thickness between center and periphery of the DSAEK graft induces a change in posterior corneal curvature, resulting in a hyperopic shift that decreases with time and is negligible for spectacle correction. However, when performing a triple procedure, intraocular lens selection should take into account the refractive change induced by DSAEK., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.