Busin Glide Research Articles

Clinical Outcomes of the Intraocular Lens Injector and Busin Glide for Descemet Stripping Automated Endothelial Keratoplasty in Patients with Iridocorneal Endothelial Syndrome.

Purpose: To report the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) performed in iridocorneal endothelial (ICE) syndrome patients using the intraocular lens injector (injector), in comparison with those using the Busin glide. Methods: In this retrospective, interventional comparative study, we evaluated the outcomes of DSAEK performed using the injector (n = 12) or the Busin glide (n = 12) for patients with ICE syndrome. Their graft position and postoperative complications were recorded. Their best-corrected visual acuity (BCVA) and endothelial cell loss (ECL) were monitored over a 12-month follow-up period. Results: DSAEK was conducted successfully in the 24 cases. The BCVA improved from the preoperative 0.99 ± 0.61 to 0.36 ± 0.35 at 12 months after operation (p < 0.001), with no significant difference between the two groups (the injector group and the Busin group) (p = 0.933). ECL at 1 month after DSAEK was 21.80 ± 15.01% in the injector group, which was significantly lower than 33.69 ± 9.75% of the Busin group (p = 0.031). No surgery-related complications were observed in the 24 cases intraoperatively or postoperatively except that one case suffered from postoperative graft dislocation, without statistical difference between the two groups. Conclusions: At 1 month after surgery, the use of graft injector for delivering DSAEK-based endothelial graft may cause significantly less endothelial cell damage than the pull-through technique used in the application of Busin glide. The injector allows safe endothelial graft delivery without the need of anterior chamber irrigation, which increases the ratio of successful graft attachment.

Descemet Stripping Automated Endothelial Keratoplasty (DSAEK)

Purpose: The purpose of this study to analyze the visual outcome and complications of DSAEK with their management.&#x0D; Study Design: Interventional case series.&#x0D; Place and Duration of Study: Department of ophthalmology Khyber Teaching Hospital Peshawar, from January 2017 to April 2019.&#x0D; Material and Methods: Twenty-one patients were selected by convenient sampling method from the outpatient department of Khyber Teaching Hospital Peshawar. Informed written consent was obtained from all patients. Ethical approval of the study was obtained from institutional review board (IRB) of Khyber Medical College, in accordance with the declaration of Helsinki. All cases of DSAEK were performed by a single surgeon. We received the precut DSAEK tissue and then endoglide was used in 5 (23.8%) and Busin Glide in 16 (76.19%) of cases. The unfolding of the donor tissue was performed by preplaced anterior chamber maintainer using balance salt solution. Any complication either intra operative or post operative, which happened, were recorded and managed either medically, or by appropriate surgical means.&#x0D; Results: The average visual acuity before surgery was CF-1m. After DSAEK procedure, average best-corrected visual acuity was 6/36. Per-operative complications included incomplete stripping of the Descemet membrane and loss of donor button during mounting in glide. Complications in the early post-operative period were pupillary block glaucoma in 3 eyes and donor tissue dislocation in 2eyes. Late post-operative complications included edema and non-attachment after re-bubbling, late secondary glaucoma, cystoids macular edema (CME) and interface opacification.&#x0D; Conclusion: DSAEK is a promising alternative in corneal endothelial de-compensation to penetrating Keratoplasty.

Five-Year Outcomes of Ultrathin Descemet Stripping Automated Endothelial Keratoplasty.

To report 5-year outcomes of ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) with a central graft thickness intended to be <100 μm. This retrospective, consecutive, interventional case series included 354 eyes with endothelial decompensation due to various causes (Fuchs endothelial dystrophy, pseudophakic or aphakic bullous keratopathy, failed previous graft, herpetic endothelitis, or buphthalmos). Donor tissue was prepared using the microkeratome-assisted double-pass technique aiming at a graft thickness <100 μm. The Descemet membrane was stripped under air. The graft was delivered into the anterior chamber using the pull-through technique through a 3.2-mm clear corneal incision using a modified Busin glide. The best spectacle-corrected visual acuity (BSCVA), endothelial cell loss, graft survival rates, and immunologic rejection rates were evaluated. Follow-up data at 1, 2, 3, and 5 years after UT-DSAEK were collected from 214, 172, 147, and 105 eyes, respectively. After excluding eyes with comorbidities, BSCVA better than or equal to 20/20 was recorded in 36.3%, 37.4%, 46.4%, and 53.4% of eyes, respectively, whereas BSCVA better than or equal to 20/40 was documented in 95.5%, 95.3%, 96.0%, and 96.6% of eyes, respectively. The mean endothelial cell loss was 35.4%, 42.3%, 43.3%, and 52.3%; Kaplan-Meier graft survival probability was 99.1%, 96.2%, 94.2%, and 94.2%, and Kaplan-Meier cumulative probability of a rejection episode was 3.4%, 4.3%, 5%, and 6.9% at 1, 2, 3, and 5 years, respectively. UT-DSAEK grafts allow excellent 5-year outcomes, including BSCVA, endothelial cell density, and survival rates comparable with those recorded post-Descemet membrane endothelial keratoplasty, but with a higher immunologic rejection rate.

Clinical evaluation of a newly developed graft inserter (NS Endo-Inserter) for Descemet stripping automated endothelial keratoplasty.

PurposeThe aim of this study was to describe the postoperative outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) performed using our newly developed graft inserter (NS Endo-Inserter) and compare the findings with those for DSAEK performed using the Busin glide.Patients and methodsIn this retrospective, case-control, institutional study, we studied the clinical outcomes of DSAEK performed using the NS Endo-Inserter (NS group, n=13) or the Busin glide (Busin group, n=10) for patients with corneal endothelial dysfunction. Clinical parameters, including the distance-corrected visual acuity (DCVA), endothelial cell (EC) loss, and intraoperative/postoperative complications, were assessed over a 6-month follow-up period.ResultsAt 6 months after surgery, the mean DCVA showed no significant difference between the two groups. EC loss at 3 and 6 months after DSAEK was 9.1%±20.7% and 18.2%±22.6%, respectively, in the NS group and 44.0%±25.5% and 46.5%±23.3%, respectively, in the Busin group; differences between groups were statistically significant at both 3 and 6 months (P=0.024 and P=0.016, respectively). Anterior chamber hemorrhage was observed in one patient in the Busin group. Rebubbling after surgery was required for one eye in the Busin group. No complications were observed in the NS group.ConclusionOur newly developed graft inserter for DSAEK may cause significantly less EC damage than the conventional pull-through technique using the Busin glide. Our inserter permits safe endothelial graft delivery without anterior chamber collapse and can result in successful graft attachment without complications at 6 months after surgery.

Hypoxia and the Prolyl Hydroxylase Inhibitor FG-4592 Protect Corneal Endothelial Cells From Mechanical and Perioperative Surgical Stress.

To determine whether hypoxia preconditioning can protect corneal endothelial cells from mechanical stress and perioperative procedures mimicking Descemet stripping automated endothelial keratoplasty (DSAEK). Preconditioning was delivered by 2 hours of 0.5% oxygen incubation in a hypoxia chamber or by exposure to the prolyl hydroxylase inhibitor FG-4592, which prevents hypoxia-inducible factor-1 alpha degradation. Damage to whole corneas was produced by brief sonication. To mimic use with DSAEK, FG-4592-preconditioned and control donor corneas were dissected with a microkeratome, and the posterior donor button was pulled through a transplant insertion device (Busin glide). The area of endothelial damage was determined by trypan blue staining. In all cases, hypoxia preconditioning or incubation with FG-4592 protected corneal endothelial cells from death by mechanical stress. Hypoxia-preconditioned human and rabbit corneas showed 19% and 29% less cell loss, respectively, relative to controls, which were both significant at P < 0.05. FG-4592 preconditioning reduced endothelial cell loss associated with preparation and insertion of DSAEK grafts by 23% relative to the control (P < 0.01). These results support the hypothesis that preconditioning by hypoxia or exposure to FG-4592 improves corneal endothelial cell survival and may also provide protection during surgical trauma.

New Graft Inserter for Descemet Stripping Automated Endothelial Keratoplasty

The aim of this study was to introduce a newly developed graft inserter for Descemet stripping automated endothelial keratoplasty, which can be readily used with 1 hand, and to examine endothelial cell loss (ECL) after graft insertion using this new inserter in an ex vivo rabbit model. Rabbit corneal grafts (∼150 μm) were prepared by using a femtosecond laser. The grafts were inserted into an artificial anterior chamber by the pull-through technique using a Busin glide or the push-out technique using our new inserter. ECL was evaluated by means of trypan blue and alizarin red S staining. Grafts that were not injected served as a control group. The mean percentages of ECL area in the control, Busin glide, and new inserter groups were 18.7 ± 1.79%, 25.4 ± 2.32%, and 24.7 ± 1.56%, respectively. The mean percentages of the ECL area in both the Busin glide group and new inserter groups were significantly greater than that in the control group (P = 0.001). There was no statistically significant difference between the Busin glide group and the new inserter group. Our new inserter may provide a favorable option for donor tissue insertion in Descemet stripping automated endothelial keratoplasty procedures.

Challenges in pediatric endothelial keratoplasty

We performed endothelial keratoplasty (EK) in three eyes of two siblings (2.5 years, male and 3.5 years, female) with congenital hereditary endothelial dystrophy (CHED) and report the intraoperative and postoperative difficulties. Repeated iris prolapse, apprehension of crystalline lens touch due to positive vitreous pressure, and need for frequent air injections to attach the graft were intraoperative challenges in all three eyes. These were addressed by use of Sheet's glide instead of Busin's glide during graft insertion and suturing of main and side ports before air injection. One eye had graft dislocation on second postoperative day due to eye rubbing by the child. Graft was repositioned with air and a venting incision was created. Postoperative examination required repeated general anesthesia. Corneal edema resolved completely in all three eyes. Present case series highlights the possible intraoperative and postoperative challenges and their solutions in pediatric EK for CHED.

Thin lenticule Descemet's stripping automated endothelial keratoplasty: single, slow pass technique

To evaluate the outcomes of single pass thin lenticule sutureless Descemet's stripping automated endothelial keratoplasty with donor lenticules prepared using a 400 μm microkeratome head. Interventional case series. Cases with corneal endothelial dysfunction. Fifteen cases with corneal endothelial dysfunction (eight pseudophakic bullous keratopathy, three Fuchs' endothelial dystrophy, three congenital hereditary endothelial dystrophy and one failed graft) underwent thin lenticule Descemet's stripping automated endothelial keratoplasty at a tertiary care hospital. Donor lenticule was prepared with a single pass 400 μm Carriazo Barraquer microkeratome (Moria, Antony, France) head. Sutureless Descemet's stripping automated endothelial keratoplasty was performed in all the cases through a 3.5 mm corneoscleral tunnel using a Busin glide for graft insertion. Main parameters evaluated were postoperative donor lenticule thickness and best-corrected visual acuity. Donor lenticules were harvested successfully for all 15 cases without any complications. At 6-months follow up, the mean logMAR best-corrected visual acuity improved from 1.87 ± 0.52 to 0.109 ± 0.11 (P = < 0.0001). The mean donor lenticule thickness was 111 ± 17.62 μm (range 70-134 μm) at the last follow up. The mean endothelial cell loss was 26.33 ± 1.34%. Thin donor lenticules for Descemet's stripping automated endothelial keratoplasty can be safely harvested using a single pass technique with 400 μm microkeratome head and can be used for a successful Descemet's stripping automated endothelial keratoplasty surgery.

Ultrathin Descemet's Stripping Automated Endothelial Keratoplasty with the Microkeratome Double-Pass Technique: Two-Year Outcomes

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. Prospective, consecutive, interventional case series. 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). 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. Best spectacle-corrected visual acuity (BSCVA), manifest refraction, endothelial cell density, and graft thickness (GT). 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. 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. Proprietary or commercial disclosure may be found after the references.

Descemet&amp;rsquo;s stripping and non-Descemet&amp;rsquo;s stripping automated endothelial keratoplasty for microcornea using 6.0 mm donor grafts

BackgroundThe purpose of this paper is to report our experience of Descemet’s stripping and non-Descemet’s stripping automated endothelial keratoplasty (DSAEK/nDSAEK) for microcorneas using 6.0 mm donor grafts.MethodsThree eyes of two patients (a 56-year-old woman and a 59-year-old woman) with microcornea and suffering from bullous keratopathy were treated with either DSAEK or nDSAEK. A small donor graft (6.0 mm) was inserted into the anterior chamber using a double glide (Busin glide and intraocular lens sheet glide) donor insertion technique. Both patients were followed for at least 12 months. Clinical outcomes, including intraoperative and postoperative complications, visual acuity, and endothelial cell density were evaluated.ResultsIn all three cases (100%), no intraoperative complications were noted. In one case with a flat keratometry value (32.13 D), a partial donor detachment was noted one day postoperatively, but it was reattached by rebubbling. In another case, rejection was noted 8 months postoperatively, but treatment with systemic corticosteroids was successful. A clear cornea remained in all three cases (100%), with best-corrected visual acuity greater than 20/100 (mean 20/50) at 12 months. Mean postoperative endothelial cell counts were 2,603 ± 18 cells/mm2 at 6 months (7.4% decrease from preoperative donor cell counts) and 1,799 ± 556 cells/mm2 at 12 months (36.5% decrease).ConclusionWe report for the first time the successful use of a small donor graft (6.0 mm) for DSAEK/nDSAEK in cases of microcornea. Additional stud ies using a large number of patients are required to evaluate fully the potential advantages and drawbacks of small diameter donor grafts for microcornea.

Double-Glide Method Using Cathereep Protective Sheet As a Substitute in Descemet's Stripping Automated Endothelial Keratoplasty

Purpose. For the insertion of the donor graft in Descemet's stripping automated endothelial keratoplasty (DSAEK), the double-glide method using a Busin glide and intraocular lens (IOL) glide concomitantly has been shown to be effective. The aim of this report is to evaluate the results for the double-glide method using Cathereep (Nichiban, Tokyo, Japan), a protective sheet made of polyurethane film for medical use, as a substitute for an IOL glide. Materials and Methods. The subjects were 10 eyes of 10 patients with bullous keratopathy. The DSAEK operation was performed, and the double-glide method was used for the donor graft insertion. During the operation, an IOL glide was used for the 5 eyes, and the Cathereep protection sheet was used for the remaining 5 eyes. We trimmed approximately 5 mm wide strips from the nonadhesive area surrounding the Cathereep protection sheet. Results. The donor graft was inserted equally easily with the Cathereep protective sheet and IOL glides and improvement of visual acuity was noted in both groups significantly. A favorable postoperative course was obtained with no perioperative complications including endothelial damage. Conclusions. Cathereep protective sheet can be used as a substitute for an IOL glide for double-glide method in DSAEK.

Descemet stripping automated endothelial keratoplasty for microcornea

Our aim was to evaluate the surgical technique and postoperative results of Descemet stripping automated endothelial keratoplasty (DSAEK) for bullous keratopathy in eyes with microcornea. Two patients with microcornea (8.8 mm in case 1 and 9.3 mm in case 2) and bullous keratopathy after cataract surgery or after laser iridotomy were treated by DSAEK. A donor lamella with a smaller diameter (7.5 mm) was inserted into the anterior chamber using the double-glide donor insertion technique (Busin glide with intraocular lens sheet glide). No intraoperative or postoperative complications occurred. Corrected visual acuity improved from counting fingers to 0.222 logMAR in case 1 and from 1.000 to 0.155 logMAR in case 2 over 6 months. Corneal endothelial cell loss was 6.5 % in case 1 and 1.9 % in case 2. DSAEK was useful for bullous keratopathy in patients with microcornea. However, surgery should be done with meticulous care, and modification of the diameter of the donor lamella and of the donor insertion technique may be required.

Descemet stripping automated endothelial keratoplasty in pediatric age group

PurposeTo report the outcomes of DSAEK surgery performed in pediatric patients. DesignNoncomparative interventional case series. Subjects and methodsAll pediatric patients (age up to 16years) undergoing Descemet automated stripping endothelial keratoplasty (DSAEK) at our Institution since January 2008 have been enrolled in a prospective study. A standard DSAEK, involving delivery of an 8.5–9.5mm graft by Busin glide, was performed under general anesthesia in 19 eyes of 11 pediatric patients (congenital hereditary endothelial dystrophy n=13; congenital glaucoma n=2; posterior polymorphous dystrophy n=2, and failed penetrating keratoplasty n=2). Slit-lamp examination, refraction and visual acuity as well as endothelial cell density were evaluated preoperatively as well as 1, 3, 6, 12, and 18months postoperatively. ResultsAll surgical procedures were uneventful. Graft detachment occurred in 4 cases and was managed successfully with repeat air injection. All corneas cleared within a week from surgery. Follow-up was 3–18months. At last follow-up examination, best-corrected visual acuity (BCVA) was better than 20/40 in 8 of the 13 cases of patients old enough to assess vision. A graft rejection episode was seen in 1 case within 3months from surgery but was reverted with steroidal treatment. No graft failures were observed. ConclusionsDSAEK is an appropriate surgical intervention for children with corneal endothelial failure. In contrast to penetrating keratoplasty (PK), DSAEK is performed under “closed system” conditions, thus minimizing intraoperative risks. Finally, healing is much faster than with PK and all sutures can be removed within 2–4weeks from surgery, thus allowing fast visual recovery and prompt starting of amblyopia treatment.

A sliding technique to load thin endothelial donor lamella onto Busin glide for Descemet-stripping automated endothelial keratoplasty

We describe a modified technique for loading donor corneal endothelial lamella onto a Busin glide® without causing wrinkles, as part of the procedure of Descemet-stripping automated endothelial keratoplasty. Briefly, after punching out a composite of the donor-endothelial lamella and a microkeratome-dissected cap, several drops of dispersive ophthalmic viscosurgical device are placed onto the endothelial surface. The Busin glide surface is then wetted with several drops of balanced salt solution. After the composite is transferred onto the Busin glide, hydrodissection of the potential space between the donor-endothelial lamella and the microkeratome-dissected cap is carefully performed to enable smooth detachment of these two lamellae. Whereas simply dragging the donor-endothelial lamella directly onto the glide can cause wrinkling or folding of the donor lamella, this technique enables smooth detachment of the composite without wrinkle or fold formation, and results in less endothelial cell damage.

A Prospective Study Comparing EndoGlide and Busin Glide Insertion Techniques in Descemet Stripping Endothelial Keratoplasty

To compare a new insertion method using an EndoGlide (Angiotech/Network Medical Products) with the standard Busin glide (Moria USA) assisted insertion of the posterior lamellar corneal graft in Descemet stripping endothelial keratoplasty (DSEK). Prospective, consecutive, comparative, nonrandomized study. Surgery was performed between October 2008 and October 2010 in 52 eyes of 52 consecutive patients with endothelial dysfunction suitable for DSEK. Twenty-two consecutive eyes underwent the new EndoGlide-assisted insertion of donor lenticule and 30 eyes underwent the surgery using the Busin glide. Six-month follow-up data are available for all patients. Clinical details, best-corrected visual acuity, manifest refraction, intraoperative and postoperative complications, and corneal endothelial cell loss were assessed at 6 months after DSEK. At 6 months after surgery, the best-corrected visual acuity was similar in both groups (0.13 logarithm of the minimal angle of resolution in the EndoGlide eyes as compared with 0.15 logarithm of the minimal angle of resolution in the Busin group; P = .34). Mean spherical equivalent was 0.65 diopter (D) and 0.51 D, and mean refractory cylinder was 1.39 D and 1.08 D, respectively (P = .40). The endothelial cell loss was much lower in the EndoGlide group (25.76%) as compared with the Busin group (47.46%; P < .0001). In conclusion, the new EndoGlide results in significantly less endothelial cell loss than Busin glide donor insertion in DSEK. The visual outcomes and refractive changes were similar in both groups.

Successful Descemet Stripping Endothelial Keratoplasty in Congenital Hereditary Endothelial Dystrophy

To report successful Descemet stripping endothelial keratoplasty (DSEK) in a patient with congenital hereditary endothelial dystrophy (CHED). A 19-year-old boy presented with complaints of decreased vision, hazy corneas, and nystagmus since birth. Six months prior, the right eye had undergone penetrating keratoplasty. In the left eye, he was planned for DSEK. Successful Descemet membrane (DM) scoring and stripping was achieved with a reverse Sinskey hook after trypan blue staining. Manually dissected posterior stromal donor tissue was transplanted using Busin glide. Corneal edema resolved completely with a final best-corrected visual acuity of 20/100 at 6 months. Serial anterior segment optical coherence tomography scans showed maximum decrease in stromal thickness in the first month. Despite resolution of corneal edema, mild stromal haze persisted, which decreased with time. Histopathology of removed DM showed thickened DM and absence of endothelial cells which was suggestive of CHED. To the best of our knowledge, this is the first reported case of successful DSEK in a patient with CHED.

Descemet Stripping Automated Endothelial Keratoplasty Using Cultured Corneal Endothelial Cells in a Rabbit Model

To investigate the feasibility of Descemet stripping automated endothelial keratoplasty (DSAEK) using cultured human corneal endothelial cells (HCECs) in an animal model. Descemet stripping automated endothelial keratoplasty grafts were produced by seeding cultured HCEC suspensions onto human corneal stromal discs. Three insertion techniques were assessed in an ex vivo model. The feasibility of DSAEK grafts with cultured HCECs was examined in a rabbit model. Rabbits received stromal disc transplants with cultured HCECs (c-DSAEK) or without HCECs (controls). The HCECs on the DSAEK grafts had a consistent size and polygonal shape. Mean (SD) percentage of cell loss in the taco-folding group (38.7% [5.2%]) was significantly greater than that in the Busin glide (11.6% [1.5%]; P = .001) and lens glide (18.0% [5.4%]; P = .007) groups. Corneal transparency gradually recovered in the c-DSAEK group, whereas edema persisted for up to 28 days in controls. Histologic examination after surgery revealed donor HCECs covering the posterior surface of the graft in the c-DSAEK group. Further enhancements of the efficacy and safety of DSAEK using cultured HCECs will make this a clinically feasible alternative therapy for corneal endothelial dysfunction. Descemet stripping automated endothelial keratoplasty using cultured HCECs may be a novel therapeutic approach to treat corneal endothelial dysfunction.

Endothelial Keratoplasty: The Influence of Insertion Techniques and Incision Size on Donor Endothelial Survival

To determine the acute endothelial cell damage from trephination and tissue insertion in endothelial keratoplasty (EK) surgery. The influence of insertion technique (forceps insertion vs "pull-through" insertion) of donor tissue and incision size (3 vs 5 mm length) was assessed. Forty precut 8.-mm-diameter donor posterior buttons were used in this study. Thirty-five buttons were inserted through a limbal incision of either 3 or 5 mm length into the anterior chamber of cadaver eyes and then removed through an open sky technique without further trauma. Five buttons that were trephined but not inserted served as a control group. Vital dye staining and computer digitized planimetry were used to analyze the tissue and quantify the total damaged area over the entire endothelial surface. Five buttons for each of 7 insertion techniques were used. The 8 tissue groups evaluated were as follows: group 1: control group of trephination only, with no insertion; group 2: forceps with folded tissue through 5-mm incision; group 3: suture pull through of nonfolded tissue through a 5-mm incision; group 4: forceps pull through of Busin glide folded tissue through a 5-mm incision; group 5: forceps with folded tissue through a 3-mm incision; group 6: suture pull through with folded tissue through a 3-mm incision; group 7: suture pull through with nonfolded tissue through a 3-mm incision; and group 8: forceps pull through of Busin glide folded tissue through a 3-mm incision. The control group demonstrated 9% +/- 2% peripheral cell damage from simple trephination of the tissue but without insertion. In the 5-mm incision surgeries, forceps insertion (group 2) caused 18% +/- 3% loss, suture pull-through insertion (group 3) caused 18% +/- 2% loss, and Busin glide pull through (group 4) caused 20% +/- 5% loss. There were no significant differences in damage between any of the 5-mm incision group techniques (P > 0.99). In the 3-mm incision surgeries, forceps insertion (group 5) caused a 30% +/- 3% loss, pull through with folded tissue (group 6) caused 30% +/- 5% loss, pull through with nonfolded tissue (group 7) caused 56% +/- 4% loss, and Busin glide pull through (group 8) caused a 28%+/- 5% loss. There was no difference in damage among the 3-mm groups (P > 0.96), with the exception of group 7 where pulling the unfolded tissue through a 3-mm incision was significantly worse than all other techniques (P < 0.001). There was significantly greater cell area damage in the 3-mm groups (36%) than in the 5-mm groups (19%) (P <0.001). Large patterns of striae with cell loss were seen in the 3-mm groups emanating from the peripheral traction site, regardless of whether the traction to pull the tissue through the incision and into the chamber was generated by a suture or cross-chamber forceps. Direct forceps insertion caused circular patterns of injury at the tip compression site regardless of incision size, but this damage was multiplied and exacerbated by insertion through a smaller incision. Smaller size (3 mm) incisions for EK surgery result in greater acute endothelial area damage than larger size (5 mm) incisions. Pull-through insertion techniques through a 5-mm incision seem equivalent in the amount of induced area damage to that of forceps insertion. Compressive injury from the incision appeared less when the tissue was folded than when not folded. Insertion with any technique through a 3-mm incision resulted in larger areas of endothelial damage. All these iatrogenic death zones outside the central endothelial area would be missed clinically by standard early specular microscopy after EK surgery.

Descemet Stripping with Automated Endothelial Keratoplasty for Bullous Keratopathies Secondary to Argon Laser Iridotomy-Preliminary Results and Usefulness of Double-Glide Donor Insertion Technique

Manipulation of the endothelial donor lamella in the anterior chamber during Descemet stripping with automated endothelial keratoplasty (DSAEK) is often difficult, especially in cases with bullous keratopathies (BK) secondary to argon laser iridotomy (ALI). We developed a novel nonfolding donor insertion technique using a Busin glide and an intraocular lens (IOL) sheet glide and evaluated post-DSAEK outcomes for ALI-induced BK using several insertion techniques. Fourteen patients (mean age, 74.2 +/- 4.9 years) with ALI-induced BK underwent DSAEK; simultaneous cataract surgery was performed in 12 patients. Donor insertions were done by taco-folding (n = 4), spatula-assisted (n = 3), Busin glide-assisted (n = 2), and Busin glide/IOL glide-assisted methods (n = 5). Endothelial cell counts, postoperative visual acuity, induced astigmatism, and complications were examined over a mean follow-up period of 228.3 +/- 132.2 days (range 58-458 days). In 1 case, DSAEK was converted to penetrating keratoplasty because of difficulties in donor insertion by the taco-folding method, resulting in vitreous prolapse. Overall, mean postoperative endothelial cell count was 1654.2 +/- 532.3 cells/mm2 (range 853-2610 cells/mm2), a 44.9% reduction compared with donor counts (mean 3003.3 +/- 425.5 cells/mm2). All patients reached acuity >20/40, with 3 (23.1%) reaching 20/20. Mean induced astigmatism in measurable cases was 0.53D +/- 0.38D. Although nonsignificant due to the small sample size, use of Busin glide with (37.9%) or without IOL glide (37.0%) tended to cause less endothelial damage than taco-folding (49.0%) or pull-through with spatula (44.2%) at 3 months postoperatively. DSAEK is effective in eyes with ALI-induced BK. Our results suggest that insertion with a Busin glide is reliable and associated with less endothelial cell damage than the conventional taco-folding technique. Simultaneous use of IOL glide (Kobayashi double-glide method) to help prevent iris prolapse is our preferred insertion method for narrow-angle eyes.

A Modified Technique for Descemet Membrane Stripping Automated Endothelial Keratoplasty to Minimize Endothelial Cell Loss

In an attempt to enhance postoperative survival of donor endothelium, the conventional technique for Descemet membrane stripping automated endothelial keratoplasty (DSAEK) was modified using the prototype of a glide specially designed to facilitate graft delivery and minimize surgical trauma. Instead of using the so-called taco technique, the Busin glide is loaded with the donor lamella, and a microincision forceps is inserted into a temporal side entry and passed across the anterior chamber, exiting through a nasal clear cornea tunnel to grab the graft and drag it into the eye. In 10 patients who underwent DSAEK, mean (SD) postoperative endothelial cell loss was 20.0% (2.6%) at 6 months, 23.5% (2.8%) at 12 months, and 26.4% (2.7%) at 18 to 24 months. Reduced trauma to the graft using our modified technique limits endothelial cell loss after DSAEK to the level recorded after conventional penetrating keratoplasty (PK).