During Descemet Stripping Automated Endothelial Keratoplasty Research Articles

Immunohistochemical Findings in Retrocorneal Membranes of Eyes with Corneal Decompensation after Complicated Intraocular Surgery.

Retrocorneal membranes (RCMs) may result from epithelial ingrowth, stromal keratocytic downgrowth, fibrous metaplasia of the corneal endothelium, or a combination of these processes. In an institutional case series, the clinical history, ocular findings, and immunohistochemical staining results of RCMs were analysed in patients with unilateral corneal decompensation after complicated intraocular surgery. Between January 2021 and September 2022, six retrocorneal membranes were excised during Descemet's stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) procedures and classified after screening with haematoxylin and eosin, periodic acid-Schiff, elastic van Gieson staining, and immunohistochemical screening with cytokeratin 7 (CK7), anti-cytokeratin (CAM5.2 and AE1/3), cell surface glycoprotein CD34, smooth muscle actin (α-SMA), and vimentin. On the basis of the immunohistochemical screening, the majority of excised RCMs (5 of 6) could histopathologically be classified as membranes originating from fibrous metaplasia of the corneal endothelium. All these RCMs were positive for CK7, α-SMA, and vimentin and negative for CAM5.2 and CD34. In one patient, an RCM had developed after 18 days of corneal contact to a free-floating dexamethasone implant in the anterior chamber and was classified as originating from stromal keratocyte downgrowth (α-SMA- and vimentin-positive, all others negative). All eyes in this series had a previous history of complicated cataract surgery, partially with subsequent intraocular lens exchange. No eyes after previous penetrating keratoplasty were in this series. In this series of eyes with previous complicated intraocular interventions (in most cases cataract surgery and revisions), the dominating RCM belonged to the type originating from fibrous metaplasia of the corneal endothelium.

Intraoperative Interface Fluid Dynamics and Clinical Outcomes for Intraoperative Optical Coherence Tomography–Assisted Descemet Stripping Automated Endothelial Keratoplasty From the PIONEER Study

To correlate intraoperative interface fluid dynamics during Descemet stripping automated endothelial keratoplasty (DSAEK) using intraoperative optical coherence tomography (iOCT) in the Prospective Intraoperative and Perioperative Ophthalmic Imaging with Optical Coherence Tomography (PIONEER) study with postoperative outcomes. Prospective consecutive, interventional, comparative case series. One hundred seventy-eight eyes of 173 patients undergoing DSAEK from the Cole Eye Institute, Cleveland, Ohio. Eyes that underwent DSAEK between October 2011 and March 2014 from the PIONEER intraoperative and perioperative OCT study were included. An automated interface fluid segmentation algorithm evaluated intraoperative dynamics of interface fluid before and after surgical manipulations. iOCT images were also captured at multiple intraoperative time points for 2 different DSAEK techniques, 1 that used an active air infusion system and 1 that did not. Interface fluid metrics, graft nonadherence. iOCT measurements of interface fluid after final surgical manipulations and immediately before leaving the operating room identified that total fluid volume (P= .002), largest fluid volume pocket (P= .002), max fluid area (P= .006), mean fluid thickness (P=.03), and max fluid thickness (P= .01) significantly correlated with graft nonadherence rates within the first postoperative week. After placement and optimization of intraoperative lenticle adherence, iOCT revealed a significant difference between the area, volume, and thickness of maximum fluid pockets between the 2 surgical techniques, but both techniques resulted in significant reduction of interface fluid during the procedure. Larger residual interface fluid volume, area, and thickness at the end of surgery detected with iOCT are associated with early graft nonadherence and can be quantified with an automated algorithm. iOCT imaging can successfully capture technique-dependent differences in fluid dynamics during DSAEK.

Double-Ring Sign to Confirm Correct Orientation of Donor Lenticules During Descemet Stripping Automated Endothelial Keratoplasty.

To describe a sign that can confirm the correct position of donor lenticules during Descemet stripping automated endothelial keratoplasty (DSAEK). In this clinical and laboratory study, DSAEK was performed in 3 eyes with a diagnosis of pseudophakic bullous keratopathy. Additionally, 2 whole globes and 2 precut corneoscleral buttons were procured for the purpose of the laboratory part of the study. After removal of recipient Descemet membrane, the donor graft was inserted into the anterior chamber, unfolded, and attached to the posterior corneal stroma with an air bubble. A similar procedure was performed in the eye-bank eyes with lenticules attached in both correct and upside-down orientations. After the anterior chamber was completely filled with air, 2 or more concentric shiny rings were formed at the border of the donor lenticule because of total internal reflection in the graft. In the live and eye-bank eyes with a donor graft attached in the correct orientation, the innermost shiny ring, indicating the stromal side of the graft, was observed under the recipient cornea, whereas the outermost ring, indicating the endothelial side, was formed deeper. When the donor lenticule was intentionally implanted upside down in the eye-bank eyes, the reverse situation occurred, and the largest ring was observed just beneath the recipient cornea. The correct anterior-posterior orientation of the donor lenticule during DSAEK could be identified by the shiny rings formed at the border of the graft after the anterior chamber was completely filled with air.

Outcomes of Descemet Stripping Automated Endothelial Keratoplasty in Patients With an Anterior Chamber Versus Posterior Chamber Intraocular Lens

The aim of this study was to assess the implications of a retained anterior chamber intraocular lens (ACIOL) during Descemet stripping automated endothelial keratoplasty (DSAEK) and to compare the outcomes in this group with those in patients who underwent DSAEK and had a posterior chamber intraocular lens (PCIOL). This is a retrospective cohort study conducted in a tertiary medical center, which compares patients who underwent DSAEK and had a retained ACIOL with patients who underwent DSAEK and had a PCIOL regarding operative and postoperative complications, visual acuity, endothelial cell density, and long-term graft survival. Eleven eyes with an ACIOL and 50 eyes with a PCIOL met the study criteria. No significant differences were found between the groups in terms of operative complications, change in visual acuity, graft survival, and endothelial cell loss. DSAEK in the setting of an ACIOL produced similar results to those of uncomplicated PCIOL cases. Although further studies are needed to gain more accurate information on this subject, it seems that DSAEK can be performed while retaining an ACIOL with favorable results.

Efficacy of Intraoperative Anterior Segment Optical Coherence Tomography during Descemet's Stripping Automated Endothelial Keratoplasty

Purpose. To examine the graft-host interface during Descemet's stripping automated endothelial keratoplasty (DSAEK) surgery with optical coherence tomography (OCT). Design. Prospective, interventional case series. Patients and Methods. Eight patients who underwent a DSAEK were included. A handheld OCT was used intraoperatively to examine the presence of interface fluid between the host cornea and the graft. Results. In 3 patients, no interface fluid was detected between the host cornea and the graft after the graft was attached by air injection. In 4 patients, interface fluid was detected after the graft was attached by air injection. The remaining interface fluid was drained through corneal stab incisions. One patient required a second surgery because the first surgery failed due to persistence of the interface fluid. All patients showed a complete attachment of the graft at one month after the DSAEK surgery. Conclusion. A handheld OCT is useful to detect the interface fluid between the host cornea and the graft during a DSAEK.

Posterior Dislocation and Immediate Retrieval of a Descemet Stripping Automated Endothelial Keratoplasty Graft

To report a case of intraoperative graft dislocation into the vitreous cavity during Descemet stripping automated endothelial keratoplasty (DSAEK) in an aniridic eye despite the presence of an iris prosthetic lens, and the surgical technique for immediate rescue of the donor lenticule. A 30-year-old man, who had undergone previous pars plana vitrectomy, penetrating keratoplasty, and iris prosthetic lens implantation (Morcher Aniridia Implants 67G) for traumatic aniridia, underwent DSAEK for failed penetrating keratoplasty. Intraoperatively, the graft dislocated into the posterior segment through the gap between the lens implant and the scleral wall. The dislocated graft was grasped with a 23-gauge vitrectomy forceps inserted through the temporal scleral incision and the implant-scleral wall gap. The straight endoglide insertion forceps was then introduced through a nasal paracentesis and used to pull the donor from the posterior segment into the anterior chamber through the implant-scleral wall gap. Postoperatively, the patient did well with no evidence of graft dislocation or retinal detachment, and rapid clearing of the donor and recipient cornea. Donor endothelial cell loss was only 11% at 6 months after DSAEK. Graft dislocation into the vitreous cavity can occur during DSAEK, even in the presence of a large iris prosthetic lens implant. In a previously vitrectomized eye, immediate retrieval of the donor from the retina can be performed using a vitrectomy forceps inserted through the existing temporal scleral DSAEK incision into the posterior segment, thus obviating the need for further pars plana incisions.

Chandelier Illumination for Use During Descemet Stripping Automated Endothelial Keratoplasty in Patients With Advanced Bullous Keratopathy

We demonstrate a technique that uses chandelier illumination during Descemet stripping automated endothelial keratoplasty (DSAEK) in cases of severe bullous keratopathy. A chandelier illumination fiber inserted through the corneal side port provides sclerotic scattering-like illumination from the sclerocorneal margin and endoillumination from the anterior chamber, resulting in excellent visibility for Descemet stripping and intraocular manipulation without obstruction from a hazy cornea. In cases complicated by dense cataract, the chandelier fiber can be inserted transconjunctivally into the pars plana, providing sufficient retroillumination to perform phacoemulsification with intraocular lens implantation combined with Descemet stripping for a DSAEK triple procedure. Because of the powerful illumination and hands-free nature of the chandelier fiber, the Descemet membrane can be visualized clearly and stripped as 1 sheet without inadvertent complications. We have developed a new 25-gauge illuminated anterior chamber maintainer comprising a 25-gauge infusion cannula through which a 29-gauge chandelier fiber probe passes. Because of the resulting bright illumination and adequate irrigation flow, excellent visibility with stable anterior chamber maintenance can be concurrently obtained for Descemet stripping, endothelial graft insertion, and subsequent intraocular manipulations without the need for biological staining or ophthalmic viscosurgical products, even in patients with severe corneal haze. This technique and new device facilitates safe and simple intraocular manipulation during DSAEK and encourages surgeons to perform DSAEK in challenging cases.

Anterior chamber air–fluid exchange for graft adhesion during Descemet stripping automated endothelial keratoplasty surgery

One of the most important steps during Descemet stripping automated endothelial keratoplasty (DSAEK) is attaching the donor Descemet lenticule to the host's cornea. This is usually carried out by injecting air into the anterior chamber with a syringe and needle. We present an alternative technique using an air fluid exchange system connected to an anterior chamber maintainer used in 22 cases in our institute. This technique has proven to be simple and fast, thus facilitating the successful performance of DSAEK surgery.

Descemet Stripping Automated Endothelial Keratoplasty With a Graft Insertion Device: Surgical Technique and Early Clinical Results

To present the surgical technique and the early clinical results of the EndoGlide, a graft insertion device for use during Descemet stripping automated endothelial keratoplasty (DSAEK). Prospective interventional case series. Graft insertion with the EndoGlide was performed in 25 eyes of Asian patients with endothelial dysfunction suitable for DSAEK. Demographic and clinical details, best-corrected visual acuity, postoperative complications, and endothelial cell density (ECD) loss were documented. The prepared graft is transferred onto a preparation base and pulled into the glide capsule with forceps. Drawing the graft into the capsule curls it into a "double-coil" configuration. The assembled EndoGlide is inserted into the eye, and the graft is pulled into the anterior chamber with forceps, where it uncoils in the correct orientation with minimal manipulation. Average age was 70 years (range 28-91) and the commonest diagnosis was pseudophakic bullous keratopathy (12 eyes). Preoperative donor ECD was 2957 ± 242 cells/mm(2), median graft diameter was 8.75 mm, and all surgeries were completed successfully by 2 surgeons. There was a short learning curve in loading of the graft into the EndoGlide and in uncoiling the graft in the recipient eye. No patient had graft dislocation or primary iatrogenic graft failure. At 6 months, the mean ECD was 2586 ± 338 cells/mm(2) and mean cell loss was 13.1% in 20 eyes. At 12 months, the mean ECD was 2575 ± 289 cells/mm(2) and mean cell loss was 15.6% in 10 eyes. Graft insertion with the EndoGlide is safe in DSAEK, with a short learning curve and a low endothelial cell loss at 6 and 12 months.

Use of Intraoperative Fourier-Domain Anterior Segment Optical Coherence Tomography During Descemet Stripping Endothelial Keratoplasty

To evaluate the intraoperative use of handheld Fourier-domain optical coherence tomography (OCT) during Descemet stripping automated endothelial keratoplasty (DSAEK) to assess the donor-host interface. Prospective, observational case series. Six patients undergoing DSAEK surgery were included. OCT scans of the cornea were performed intraoperatively after insertion of the donor disc, after instillation of air in the anterior chamber beneath the disc, after vent incisions in the host cornea in each quadrant, following air-fluid exchange at the end of operation, and on day 1 after surgery. The central 3 mm of each cornea was scanned. The broadest gap between donor and host cornea (interface space) was measured. Adequate readings could be obtained from all patients without any complications. In 2 patients there was a decrease in the width of the interface space after each surgical step documented by the OCT scans. At the end of their operation, no interface space was detectable. In 2 patients, interface space disappeared after the vent incisions and did not reappear during the further course of the surgery. In further 2 patients the separation between the host and donor was still detectable at the end of the operation. All patients had no detectable interface gap on day 1. Handheld anterior segment OCT can be used to assess the host-donor interface in lamellar corneal transplantation surgery. Donor adherence can occur in spite of residual interface space at the end of surgery. Further studies should be conducted to answer the question of which surgical steps are useful in assisting with donor adhesion.

Endothelial damage of a donor cornea depending on the donor insertion method during Descemet-stripping automated endothelial keratoplasty in porcine eyes

To compare endothelial damage of the donor cornea in relation to the method of inserting the donor cornea into the recipient anterior chamber during Descemet-stripping automated endothelial keratoplasty (DSAEK). Fifteen enucleated pig eyes were used. The donor corneoscleral buttons were mounted in an artificial anterior chamber. The anterior lamella was excised using a microkeratome and punched using a trephine. The following methods were employed to insert the donor cornea into the recipient anterior chamber: (1) The donor was folded over, grasped using forceps, and inserted ("taco" technique). (2) The forceps were inserted and the edge of the donor was grasped and dragged into the chamber. (3) A loop was made at the edge of the donor by suturing with nylon. A hook was inserted to drag the donor by the loop into the chamber. After insertion, the incision on the recipient eye was extended, and the donor cornea was removed for examination. After vital staining, the samples were examined under a light microscope and a scanning electron microscope. With the taco technique, endothelial damage (17.9%) was observed in areas where the forceps held the donor. In the drag technique using forceps, endothelial damage (17.3%) was observed where the forceps made contact and in the folds in this area. In the drag technique using a suture, endothelial damage (18.8%) was observed in the area of the needle puncture and in folds in this area. The amount of endothelial damage did not differ significantly among the three different methods of donor insertion during DSAEK in this animal model, but each method exhibited a different endothelial damage pattern.

Chandelier illumination to complete Descemet stripping through severe hazy cornea during Descemet-stripping automated endothelial keratoplasty

We describe a technique that uses chandelier illumination during Descemet-stripping automated endothelial keratoplasty (DSAEK) in severe bullous keratopathy. A 25-gauge or 27-gauge chandelier illumination fiber inserted through the corneal side port serves as sclera-scattering illumination from the sclerocorneal margin and endoillumination from the anterior chamber and provides excellent visibility for Descemet stripping and intraocular manipulation without obstruction by a hazy cornea. In cases complicated by dense cataract, the chandelier fiber can be inserted transconjunctivally into the pars plana, providing sufficient retroillumination to perform phacoemulsification with intraocular lens implantation combined with Descemet stripping for a DSAEK triple procedure. Because of the powerful illumination and hands-free nature of the chandelier fiber, Descemet membrane can be visualized clearly and stripped as 1 sheet without inadvertent complications. This new technique is safe and might encourage surgeons to perform DSAEK in challenging cases.

Graft insertion during Descemet-stripping automated endothelial keratoplasty: Pulling the graft inward

We describe a technique to facilitate insertion of the folded donor graft during Descemet-stripping automated endothelial keratoplasty (DSAEK). Surgery is performed using a standard technique, and the graft is pulled into the anterior chamber using a double-armed 10-0 polypropylene suture with straight 16 mm needles. The technique of pulling the graft inside the anterior chamber is easy and ensures that the graft is inserted and unfolded in the right direction. There is no compression of tissue so mechanical trauma to the endothelium is less than when an inserting forceps is used. The results in 12 cases are presented.

Closed-chamber pulling-injection system for donor graft insertion in endothelial keratoplasty

I describe the closed-chamber pulling-injection (CCPI) technique to improve surgical control and safety of graft insertion into the anterior chamber during Descemet-stripping automated endothelial keratoplasty (DSAEK). In CCPI, the graft is rolled up (endothelium facing inward) in a closed transparent insertion device, allowing it to be drawn into a well-formed anterior chamber and unfolded smoothly. The technique has been used successfully to treat corneal decompensation in 72 consecutive cases. The results indicate that using the CCPI technique, both average and complicated cases can benefit from the numerous advantages provided by endothelial keratoplasty.