Yoav Nahum

Preloaded donor corneal lenticules in a new validated 3D printed smart storage glide for Descemet stripping automated endothelial keratoplasty

Purpose To design and validate the efficacy of three-dimensional (3D) printed smart storage glide (SSG) which is capable of preserving and delivering posterior lenticules for Descemet stripping automated endothelial keratoplasty (DSAEK). Methods Laboratory investigation (A) was followed by clinical validation (B). Unsuitable corneas for transplantation (n=20) were used for study A. These tissues were cut using a standard microkeratome, punched and loaded into the SSG and preserved for 7 days in transport media. Endothelial cell density (ECD), Trypan blue and Alizarin red staining for endothelial morphology, thickness measurements and glucose uptake, cell apoptosis and immunostaining post preservation were analysed. For study B, clinical grade corneas (n=14) were preloaded in SSG and grafted in patients with indications of Fuchs’ dystrophy (n=8), pseudophakic bullous keratopathy (n=3), posterior polymorphous dystrophy (n=2), and previous DSAEK failure (n=1). Standard DSAEK included descemetorhexis under air and bimanual delivery of the tissue under infusion of buffered saline solution through an anterior chamber maintainer placed at the 12 o’clock position. Main outcome measures for study B were less surgical time, best spectacle-corrected visual acuity (BSCVA), speed of visual recovery, and ECD. Results For study A, an average ECD loss was 2.30±3.21%, thickness increased by 30.80±20.85% and one-third of glucose was utilised during the preservation phase. Alizarin red showed hexagonality of the cells. Cell apoptosis was not observed and expression of ZO-1 was noted on the preserved tissues. In study B, 25% ECD loss was observed after 6 months. BSCVA improved to 20/25 or better within 3 months after DSAEK. Mean surgical time recorded was 21 min. Conclusions This paper describes the development, design, laboratory and clinical validation of a 3D printed SSG which helps to store and deliver posterior lenticules, therefore allowing transportation of quality-controlled precut tissues.

Risk Factors Predicting the Need for Graft Exchange After Descemet Stripping Automated Endothelial Keratoplasty.

Purpose: To identify the risk factors predicting the need for graft exchange after Descemet stripping automated endothelial keratoplasty (DSAEK). Methods: This is a retrospective cohort study. The study group included all 117 eyes that underwent or necessitated repeat DSAEK performed between January 2005 and June 2014 at Villa Serena–Villa Igea private hospitals (Forlì, Italy). The control group consisted of 1033 eyes that underwent only primary DSAEK during the same period. Demographic details, indications for primary surgery, ocular preoperative status and comorbidities, donor endothelial cell density (ECD), and postoperative complications were compared between the groups using univariate and multivariate analyses. Results: The prevalence of graft failure necessitating graft exchange was 10.2% (117 of 1150 eyes). In univariate analysis, a diagnosis of Fuchs endothelial dystrophy was a protective factor against the risk of repeat DSAEK. Prior trabeculectomy or aqueous shunt implantation, postoperative graft detachment, lower donor ECD, and a rejection episode were all associated with a significantly higher risk of requiring repeat DSAEK. The presence of buphthalmos, anterior chamber intraocular lens, aphakia, or prior penetrating keratoplasty were not risk factors for the failure of DSAEK. Of these variables, multivariate analysis showed that only prior aqueous shunt implantation [odds ratio (OR) = 5.5, 95% confidence interval (CI), 1.4–22.2], lower donor ECD (OR = 0.99, 95% CI, 0.997–0.999), and a documented postoperative rejection episode (OR = 18.2, 95% CI, 7.9–45.0) predicted the need for repeat DSAEK. Conclusions: DSAEK grafts have similarly good long-term survival regardless of the indication for surgery, lens status, or ocular comorbidities, with the only exception being the presence of an aqueous shunt.

Postoperative Graft Thickness Obtained With Single-Pass Microkeratome-Assisted Ultrathin Descemet Stripping Automated Endothelial Keratoplasty.

Purpose: To evaluate the results of microkeratome-assisted ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) using a nomogram developed for the single-pass technique. Methods: A retrospective study of eyes operated between September 2014 and March 2015 at Villa Serena-Villa Igea Private Hospitals (Forlì, Italy) by a single surgeon (M.B.). Study eyes underwent UT-DSAEK performed using a linear microkeratome-assisted lamellar dissection with disposable heads of different sizes (Moria ALTK system; Moria SA) chosen according to a pachymetry-based nomogram developed at our department. The main outcome measure was the graft thickness as assessed by means of anterior segment optical coherence tomography, measured between 1 and 3 months postoperatively. Results: Forty-two eyes were included in this study. Mean follow-up time was 5.0 ± 1.8 months (range 1.2–6.9 months). No perforation or other complication occurred during graft preparation. Mean postoperative central thickness of donor grafts was 63 ± 29 &mgr;m. Thickness ranged between 23 and 177 &mgr;m, and the second thickest graft measured 116 &mgr;m. By 3 months postoperatively, 41/42 (97%) of the grafts were of thickness ⩽130 &mgr;m and 38/42 (90%) of the grafts were of central thickness ⩽100 &mgr;m. The mean nasal-to-temporal absolute thickness difference at the grafts central 3-mm zone was 5 ± 7 &mgr;m at the last available measurement. Conclusions: The nomogram developed at our institution allowed reliable single-pass microkeratome-assisted dissection of donor tissue, creating consistently thin and symmetric grafts without loss of tissue. The results obtained compare favorably with those reported in the past for double-pass microkeratome-assisted dissection of UT-DSAEK.

Interface infection after descemet stripping automated endothelial keratoplasty: outcomes of therapeutic keratoplasty.

Purpose: The aim of this study was to evaluate the visual outcomes and graft survival rate after therapeutic keratoplasty performed for interface infection after Descemet stripping automated endothelial keratoplasty (DSAEK). Methods: This is a retrospective, interventional case series. The study population comprised 7 patients who developed unilateral post-DSAEK interface infection unresponsive to conservative treatment, with or without graft exchange, and were treated with penetrating keratoplasty (PK), 9 to 9.5 mm in diameter, with en bloc excision of the recipient cornea and DSAEK graft. The main outcome measures included best spectacle-corrected visual acuity, refractive error, histological examination, reinfection, and rejection and graft survival rates. Results: Interface infection was diagnosed in 10 (0.92%) of 1088 eyes that underwent DSAEK at our institution between 2005 and 2013. Seven of 10 eyes (0.64% of the total) were unresponsive to conservative treatment and underwent therapeutic keratoplasty. Candida and Staphylococcus species were identified in 3 cases each, and Nocardia species was identified in 1 case. With a mean post-PK follow-up of 25.4 months (range 4–60 months), no recurrence of infection was seen in any eye, and 5 of 7 PK grafts remained clear. Best spectacle-corrected visual acuity was 20/20 in 2 eyes, better than 20/50 in 4 eyes, and 20/100 or worse in 3 eyes, in 2 of which the graft had failed within 1 year of performing the PK. Conclusions: Therapeutic keratoplasty is instrumental in eliminating interface infection after DSAEK, possibly leading to excellent visual outcomes with a relatively high graft survival rate.

Factors Associated With Graft Detachment After Primary Descemet Stripping Automated Endothelial Keratoplasty

Purpose: To identify risk factors associated with postoperative graft detachment after Descemet stripping automated endothelial keratoplasty (DSAEK). Methods: In this retrospective institutional cohort study, the study group included all consecutive eyes that underwent primary DSAEK between January 2005 and October 2015 at Villa Serena-Villa Igea private hospitals (Forlì, Italy) and developed postoperative graft detachment (n = 45). The control group included all eyes that underwent primary DSAEK during the same period and did not develop graft detachment (n = 1167). The main outcome measure was whether or not postoperative graft detachment occurred. Results: Main indications for surgery included Fuchs endothelial dystrophy (525/1212 = 41%), pseudophakic bullous keratopathy (422/1212 = 35%), and a failed penetrating keratoplasty (PK) graft (190/1212 = 16%). Postoperative graft detachment occurred in 45 of 1212 (3.7%) eyes. Medically treated glaucoma, previous trabeculectomy, previous aqueous shunt procedure, and failed PK were all associated with an increased risk for graft detachment in univariate analysis. No particular lens status at the time of graft implantation was significantly associated with graft detachment, including the presence of an anterior chamber intraocular lens [odds ratio (OR), 1.5; 95% confidence interval (CI), 0.35–6.46, P = 0.58] or aphakia at the time of graft transplantation (OR, 1.37; 95% CI, 0.41–4.57, P = 0.74). Cataract removal during surgery was not associated with an increased risk for detachment (OR, 0.77; 95% CI, 0.39–1.5, P = 0.47). Previous trabeculectomy (OR, 4.21; 95% CI, 1.53–11.56, P = 0.005) and a previous failed PK graft (OR, 3.04; 95% CI, 1.6–5.78, P = 0.001) were the only independent risk factors for graft detachment in multivariate analyses. Conclusions: Previous PK and trabeculectomy are independent risk factors for postoperative graft detachment in primary DSAEK.

Two cases of ultrathin Descemet stripping automated endothelial keratoplasty utilizing a graft that had undergone radial keratotomy.

This is a report of two cases in which tissue that had undergone radial keratotomy (RK) was utilized for double-pass ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK). Postoperative slit-lamp examination, visual acuity, anterior segment optical coherence tomography, and specular microscopy were available 30 months after surgery. Both corneas from a donor, who had undergone RK several years before his demise, and were otherwise suitable for endothelial keratoplasty were prepared for UT-DSAEK using double-pass dissection using first a 300 mm microkeratome head and then a 130μm microkeratome head (ALTK system, Moria, Antony, France). After the second cut, the tissue was punched to 9.0 mm and transplanted in two eyes with endothelial decompensation according to standard technique. As early as 3 months after surgery, both patients had 20/25 best-corrected visual acuity, which remained stable for the following 27 months. Postoperative endothelial cell loss was 34% and 57% at 2.5 years. In conclusion, post-RK donor tissue can be used for UT-DSAEK.

Tectonic Descemet Stripping Automated Endothelial Keratoplasty for the Management of Sterile Corneal Perforations in Decompensated Corneas.

Purpose: To report the use of Descemet stripping automated endothelial keratoplasty (DSAEK) for treatment of sterile corneal perforations accompanying endothelial decompensation. Methods: In this multicenter interventional case series, we reviewed the medical records of all tectonic DSAEK surgeries performed at Villa Serena-Villa Igea private Hospitals (Forlì, Italy) and Rabin Medical Center (Petach Tikva, Israel) between January 2014 and March 2016. Results: Three patients with endothelial decompensation and sterile corneal perforation (n = 2) or impending corneal perforation (n = 1) underwent DSAEK between 2014 and 2015 at Villa Igea Hospital, Forlì, Italy, and Rabin Medical Center, Petach Tikva, Israel. All 3 surgeries were performed in eyes with a history of progressive stromal thinning without signs of infection, using the standard DSAEK technique. In 1 eye, surgery was complicated by bleeding into the graft–recipient interface that resolved after intraoperative interface washout. The other 2 procedures were uneventful. In all cases, the graft formed an airtight and watertight barrier, restoring the globes mechanical integrity. All grafts remained clear throughout follow-up. One eye underwent deep anterior lamellar keratoplasty (DALK on DSAEK) with resulting improvement of visual acuity. Conclusions: Standard DSAEK can be performed in the presence of corneal perforation. Surgery can be a simple technique for closure of sterile corneal perforations while treating endothelial decompensation. Internal tamponade by a lamellar graft can possibly be used in cases of corneal perforations in eyes with a healthy endothelium.

Graft–recipient Collagen Lamellar Axis Discrepancy Is Compatible With Excellent Visual Acuity After Descemet Stripping Automated Endothelial Keratoplasty

Purpose: To evaluate whether a discrepancy between the orientation of graft and recipient collagen lamellae can significantly limit the visual acuity after Descemet stripping automated endothelial keratoplasty (DSAEK). Methods: A multicenter cohort study of eyes that underwent DSAEK for Fuchs endothelial dystrophy or pseudophakic bullous keratopathy at Villa Serena-Villa Igea private Hospitals (Forlì, Italy) and at Santa Maria Nuova public hospital (Reggio Emilia, Italy), which were scheduled for a postoperative examination between July and September 2014. We have included eyes with a distance-corrected visual acuity of 8/10 or better, no ocular comorbidities, and a clear cornea. The main outcome measure was graft–recipient axis discrepancy of lamellar orientation around the visual axis as assessed by polarimetric interferometry. Results: Twelve eyes were included in this study. Eight eyes had a spectacle-corrected distance visual acuity of 8/10, 3 eyes had 9/10, and 1 eye had 10/10. In 8/12 (66.7%) eyes, 2 discernible axes of collagen lamellar orientation were identified and were all 30 degrees or more apart (range 30–90). In 2 eyes, only 1 axis was identified and in another 2 eyes, 2 axes 20 and 17 degrees apart were identified. The eye with 10/10 visual acuity presented a discrepancy of 17 degrees between lamellar axes. Conclusions: A discrepancy between the lamellar orientation of the graft and the recipient is compatible with excellent visual acuity after DSAEK.

Visual disability rates in a ten-year cohort of patients with anterior visual pathway meningiomas

Abstract Purpose: To examine the visual outcome of anterior visual pathway meningioma (AVPM) patients followed for at least one year. Methods: Data were collected on demographics, clinical course and management. Visual disability was classified at the first and last examination as follows: I – no visual disability; II – mild visual defect in one eye; III – mild visual defect in both eyes; IV – loss of driver’s license; V – legally blind. Results: Eight-one AVPM patients had their tumor originate in the clinoid process in 23 (28%), sphenoid-wing area in 18 (22%), cavernous sinus in 15 (19%), tuberculum sellae in 8 (10%), and mixed in 17 (21%). On last examination, 46 patients (57%) had good visual acuity in one or both eyes (Class I or II) and 17 (21%) were mildly affected in both eyes. The rate of Class IV disability was 16%, and Class V disability was 6%. Conclusions: Attention needs to be addressed to the considerable proportion of patients with AVPM (22% in this study) who may lose their driver’s license or become legally blind. Occupational therapists should play an important role in the multidisciplinary management of those patients to help them adapt to their new physical and social situation. Implications for Rehabilitation Anterior visual pathway meningiomas (AVPMs) are commonly not life-threatening but they can lead to profound visual disability, especially when the tumor originates in the tuberculum sellae and cavernous sinus. Particular attention should be paid to visual acuity and visual field deficits, as these can profoundly affect the patient’s quality of life including ability to drive and activities of daily living. The interdisciplinary management of patients with AVPM should include the neurosurgeon, neuro-ophthalmologist and occupational therapist. Also, early intervention by the occupational therapist can help patients adapt to their current physical and social situation and return to everyday tasks more rapidly.

Prevalence of guttae in the graft following corneal transplantation

Aim To evaluate the prevalence of guttae in donor grafts following corneal transplantation and to examine the possible effect of guttae on postoperative results. Methods Retrospective cohort study. We reviewed the medical records of all keratoplasties performed at the Villa Serena-Villa Igea private hospitals (Forlì, Italy) between January 2005 and July 2014. Endothelial specular microscopy images were examined to identify the presence of guttae. Donors age, patients age, indication for surgery, surgical procedure, postoperative visual acuity, and endothelial cell density were also noted. Results A total of 11 068 postoperative specular microscopy pictures were available for 1116 of 2332 eyes (47.9%) that underwent keratoplasty at our institution. Guttae were identified in 42 of 946 eyes (4.44%) following penetrating or endothelial keratoplasty, and in 3 of 170 eyes (1.76%) following anterior lamellar keratoplasty. Twenty-seven of these photos demonstrated a few isolated scattered guttae, nine showed widespread guttae with small patches, and nine demonstrated large patches of guttae. Last documented best spectacle-corrected visual acuity did not differ between patients with or without guttae (logarithm of the minimum angle of resolution (logMAR) 0.22±0.24 (approximately 20/32) vs 0.29±0.45 (approximately 20/40), p=0.25) nor did the groups differ in their 24-month postoperative endothelial cell density (1633±427 vs 1555±454 cells/mm2, p=0.56). No graft with postoperative guttae failed during the follow-up period of this study. Conclusions Guttae can be found in approximately 4% of post-keratoplasty grafts. At least for the initial two postoperative years, they do not negatively affect vision, endothelial cell density or graft survival.