A virtual model to assess maximum treatable area in LASIK and feasibility of a temporal hinge.

PURPOSE: To generate virtual models using different hinge locations and to investigate the advantages of a temporal hinge to a superior in LASIK. METHODS: The study design was cross sectional. An image processing software was used to construct virtual LASIK models of 56 slit lamp photos of eyes. For a given hinge location and width, the largest flap diameter and maximum treatable stromal bed area were calculated, comparing temporal hinge to superior. RESULTS: Temporal hinge allowed a greater flap diameter than superior and thus a greater treatment zone area for a given hinge width. A temporal hinge allowed a greater hinge width than a superior hinge for a given treatment zone area. CONCLUSION: We provide a rational basis for a mechanically stable temporal hinge. Moreover, we provide a method to pre-operative model flap size and hinge location, using a slit lamp camera and an image editing software.

Simultaneous Descemet's membrane endothelial keratoplasty and posterior iris-claw-fixated intra ocular lens implantation (IOL) in management of aphakic bullous keratopathy.

To evaluate the efficacy of combined procedure of Descemet's membrane endothelial keratoplasty (DMEK) and posterior iris-claw-fixated intra ocular lens (IOL) implantation in the management of aphakic bullous keratopathy (ABK). Sankara eye centre, a tertiary eye care centre. A prospective case series analysis. A prospective study comprised ten eyes of ten patients who underwent DMEK and posterior iris-claw-fixated IOL. Mean follow-up period was 12-36 months. Pre-operative and post-operative best corrected visual acuity (BCVA), endothelial cell density (ECD) and complications were noted. A total ten eyes of ten patients underwent DMEK. Out of ten patients BCVA improved from 1.00 to 1.60 LogMAR with mean and SD of 1.40 ± 0.20 to +0.20-0.40 LogMAR with mean and SD of 0.30 ± 0.07, with a significant p value of <0.001, Mean ECD of the donor tissue pre-operatively was 2367 cells, whereas 24 months post-operatively it was reduced to 1798 cells. Mean reduction in ECD pre procedure and post procedure was 569 (24 %). Iris-fixated IOL appears to offer simplicity in implantation and may be combined with DMEK in ABK. This procedure provides a faster visual recovery than other endothelial keratoplasties with iris-fixated IOL.

A simple surgical technique for splitting a single donor cornea for performing deep anterior lamellar keratoplasty and Descemet membrane endothelial keratoplasty without using a microkeratome.

PURPOSE: To describe a simple manual surgical technique for splitting a single-donor eye for performing both deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK) without using a microkeratome. METHODS: Twenty-three eyes with anterior stromal pathology and 23 eyes with irreversible endothelial dysfunction were evaluated for keratoplasty at a tertiary eye care referral center. Twenty-three healthy donor corneas were split into two parts. The Descemet's membrane was stripped and used for DMEK. The stripped stroma was used for DALK. Best-corrected visual acuity (BCVA) of both DALK and DMEK, endothelial cell density, and endothelial cell loss in DMEK were noted at 1-year follow-up, along with any intraoperative or postoperative complications and failures. RESULTS: In the DALK group, mean BCVA improved from 1.264 ± 0.25 log Mar preoperatively to 0.355 ± 0.27 log Mar at 12 months follow-up. There were no complications and failures. In the DMEK group, mean BCVA improved from 1.537 ± 0.61 log Mar preoperatively to 0.592 ± 0.67 log Mar and the mean donor ECD was 3071.66 (range, 2783-3487) cells/mm2 preoperatively, which was reduced to 1989.33 (range, 1546-2543) cells/mm2 at 12 months follow-up indicating a mean endothelial cell loss of 35%. The failure rate was 21.7%. CONCLUSION: This study demonstrates that with a single donor corneal tissue, both DALK and DMEK can be performed successfully without any complications. Our technique will help corneal surgeons in all developing countries to cost effectively perform more lamellar surgeries and help in reducing the magnitude of corneal blindness without the need for expensive microkeratomes.

Four in one: Four recepients with a single donor tissue - A novel concept for eye transplantation surgery post-COVID-19.

A donor corneo-scleral button was dissected into four parts using a simple manual technique. The anterior corneal lamellae was stripped from the Descemet's Membrane (DM) and Deep Anterior Lamellar Keratoplasty (DALK) was performed in a patient with advanced keratoconus after removing the recipient's stroma using the big bubble technique. Descemet's Membrane Endothelial Keratoplasty (DMEK) was done with the stripped donor DM in a patient with Fuch's endothelial dystroph (FECD). The cadaveric limbal stem cells from the tissue were used for simple limbal epithelial transplantation (SLET) in a Steven- Johnson Syndrome (SJS) with localized limbal stem deficiency and symblepharon. The sclera was used to revise a leaking hypotonus bleb in an advanced single-eyed glaucoma patient. No intraoperative or postoperative complications were observed. At 1 year, all the 4 cases retained healthy transplanted tissues with good visual outcomes. Shortage of donor eyes is a global problem and with the present COVID-19 scenario the situation is bound to worsen. The advent of customized component corneal transplantation using simple cost-effective techniques will be the future trend in the years to come.

Two-year clinical outcome after Descemet membrane endothelial keratoplasty using a standardized protocol.

PURPOSE: The purpose of this study is to evaluate 2-year clinical outcome after Descemet membrane endothelial keratoplasty (DMEK) in a variety of endothelial dysfunctions using a standardized protocol. METHODS: : From a group of 230 eyes which underwent DMEK for Fuchs' endothelial corneal dystrophy (FECD), aphakic and pseudophakic bullous keratopathy, failed full thickness corneal transplants, ICE syndrome, failed DSEK, and TASS the clinical outcomes [best spectacle-corrected visual acuity (BSCVA), central endothelial cell density (ECD)] were evaluated before, and at 6, 12, and 24 months and the success rate, failure rate and postoperative complications were also analyzed. RESULTS: Out of 230 eyes, 144 eyes (70%) had BSCVA 6/9 or better 2 years postoperatively. Mean donor ECD was 2692.23 (range, 2300-3436) cells/mm2 preoperatively, which was reduced to 1433.64 (range, 619.0-2272.0) cells/mm2 2 years after DMEK surgery, indicating a mean reduction of 1258 cells/mm2 (46%) in ECD. CONCLUSION: DMEK is a highly successful surgical procedure when following a standard protocol for treating diseases of the corneal endothelium providing a near perfect anatomic restoration and a high degree of visual rehabilitation.

Long-term clinical outcomes after Descemet Membrane Endothelial Keratoplasty (DMEK) in Irido-Corneal Endothelial Syndrome.

PURPOSE: To evaluate the long-term clinical outcomes after Descemet Membrane Endothelial Keratoplasty (DMEK) in Irido-Corneal Endothelial Syndrome (ICE). OBSERVATION: Four eyes of four patients diagnosed with ICE syndrome were treated with DMEK. Postoperatively, best corrected visual acuity (BCVA) and central endothelial cell density (ECD) were documented at 6, 12, 24 and 36 months for all the cases. All procedures were uneventful. Average follow-up time was 36 months. BCVA improved in all eyes. Mean BCVA improved significantly from 1.54 ± 0.71 log MAR preoperatively to 0.11 ± 0.14 logMAR at the final follow-up. Average donor ECD was 2895 ± 357 cells/mm2 preoperatively and 1992 ± 321 cells/mm2, 1816 ± 395 cells/mm2, 1571 ± 299 cells/mm2 and 1305 ± 246 cells/mm2 at 6, 12, 24 and 36 months after DMEK surgery respectively. This represented an average endothelial cell loss (ECL) of 31.3%, 37.7%, 46.8% and 55.1% at 6, 12, 24 and 36 months respectively. Postoperative intraocular pressure (IOP) rise was seen in 3 eyes at 1 month which normalized under topical antiglaucoma medications. CONCLUSION: DMEK is a relatively safe procedure providing favourable clinical outcomes in eyes with ICE syndrome. Since angle closure is progressive in these condition, regular IOP monitoring and glaucoma control is critical for long term survival of the graft. IMPORTANCE: Till date management of ICE syndrome has always been a great challenge due to its varied presentation and complex anatomical abnormalities. Replacing the endothelial cells in an irregular anterior chamber poses additional difficulty. Even well-trained DMEK surgeons find it difficult to appose the Descemet's Membrane (DM) in such a scenario and we in this article provide key surgical tips for successful long term management of these cases.

Risk for uveitis after laser in situ keratomileusis in patients positive for human leukocyte antigen-B27.

PURPOSE: To assess the incidence of, risk for, and visual outcomes of acute anterior uveitis (AAU) in human leukocyte antigen (HLA)-B27 positive patients who had laser in situ keratomileusis (LASIK). SETTING: University-based center. METHODS: This study comprised 46 eyes of 23 HLA-B27 positive patients with a 5-year follow-up. Data on episodes of uveitis were reviewed retrospectively and the incidence rates calculated for LASIK and non-LASIK eyes. Kaplan-Meier survival probabilities were calculated for uveitis occurring during the final 36 to 60 months of the study. Survival probabilities between LASIK and non-LASIK eyes were compared. RESULTS: Twenty eyes (10 patients) had LASIK a mean of 36 months+/-2 (SD) after the diagnosis of HLA-B27. In the HLA-B27 positive patients, the incidence rates of uveitis between eyes that had and eyes that did not have LASIK were not significantly different. The incidence rates of uveitis after LASIK did not differ significantly between eyes with and eyes without episodes of uveitis before LASIK (P=.135). The probability of an eye having no episode of uveitis in the fourth and fifth year of follow-up was not significantly different between eyes that had LASIK and those that did not (P=.668). CONCLUSIONS: The occurrence rate of post-LASIK AAU in the HLA-B27 positive population was not higher than the general incidence in a similar HLA-B27 population without previous LASIK. A previous episode of uveitis did not appear to increase the risk for uveitis after LASIK in HLA-B27 positive patients.

Bilateral Mooren's ulcer - Customised corneal graft with additional amniotic membrane graft.

Mooren's ulcer (MU) is a rare and painful peripheral corneal ulceration which occurs in the absence of any associated scleritis, and any detectable systemic disease. A 60-year-old male patient was referred to us with bilateral peripheral corneal ulceration. Best corrected visual acuity (BCVA) in both eyes was counting finger at one metre. The right eye showed a 180° thinning with perforation at 8 o'clock position. The left eye showed a 360° thinning with central contact lens type cornea. After complete blood analysis we started the patient on cyclophosphamide orally along with high doses of oral steroids. A crescentic excision of the thinned cornea and crescentic customised corneal graft with additional amniotic membrane graft (AMG) was done first for the right eye and a 360° peripheral lamellar corneal graft with additional AMG for the left eye. The BCVA of RE was 1/60 improving to 6/36 with plus ten aphakic glasses and LE was 3/60. Hand fashioned full thickness crescentic customised corneal graft with additional AMG and a peripheral 360° lamellar corneal graft with additional AMG in these cases are a novel approach to Mooren's ulcer with gratifying results.

Clinical features and management of ocular lesions after stings by hymenopteran insects.

We describe the ocular alterations and the management after stings from Hymenopteran insects. In all the five patients, the insect was identified as bee. The patients presented with significant corneal edema, which resolved dramatically in three of them after removal of stingers. Among the other two one went for permanent corneal decompensation and the other developed Intumuscent cataract with increased intraocular pressure. Although a rare occurrence, ocular trauma caused by Hymenopteran insects has a potential to cause severe ocular damage in humans. A high level of clinical suspicion and immediate removal of the stingers along with administration of high doses of topical and systemic steroids is a must to prevent chances of permanent corneal damage and intraocular complications.