Management of cataract in dry eye disease: Preferred practice pattern guidelines

Cataract surgery is one of the most commonly performed ophthalmic surgeries in the world. Dry eye disease (DED) is found to coexist in most patients with cataracts due to the overlapping age groups of both these conditions. Preoperative evaluation for DED is important to improve outcomes. A pre-existing DED affecting the tear film is likely to affect biometry. Moreover, special intraoperative considerations are needed in eyes with DED to reduce complications and improve postoperative outcomes. Dry eye disease (DED) is known to occur following an uneventful cataract surgery or a pre-existing DED is likely to worsen following cataract surgery as well. In these situations, despite a good visual outcome, patient dissatisfaction is common owing to the distressing DED symptoms. This review aims to summarize the preoperative, intraoperative, and postoperative considerations when performing cataract surgery in the presence of a coexisting DED.

Phototherapeutic keratectomy for recurrent granular dystrophy in postpenetrating keratoplasty eyes.

Purpose: The purpose is to assess the clinical and visual outcome after phototherapeutic keratectomy (PTK) procedure in eyes with prior penetrating keratoplasty (PKP) for granular corneal dystrophy (GCD) and the time of performance of repeat PTK for recurrence. Methods: PTK was performed for visually significant recurrence: A reduction in best‑corrected visual acuity (BCVA) by >2 lines over BCVA before recurrence was considered as visually significant recurrence. Three eyes had amniotic membrane patch performed with PTK. The main outcome measures were a recurrence of GCD, clinical course, and visual outcome. Intervals between repeat PTK procedures were noted. Results: Six patients (n = 10 eyes; males: 4, mean age 39 ± 13.97 years) underwent PTK. The mean pachymetry before first PTK was 527.1 ± 34 microns. The mean duration between PKP and first PTK was 85.1 months (range: 37–108 months). Two and three PTK procedures were done for seven and five eyes, respectively. Mean duration between first and second and second and third PTK was 62.12 ± 34.41 and 42.8 ± 13.54 months respectively. The average cut depth was 43.66 ± 19.57, 75 ± 43.30 and 39 ± 19.79 microns after the first, second and third PTK procedures, respectively. All eyes had a corneal haze. Prefirst PTK mean BCVA was 20/200 and improved significantly after the first two PTK procedures to 20/40 and after the third PTK procedure to 20/32 (P < 0.001). Five eyes had hyperopia. One acute graft rejection was managed successfully at 5 months with medical therapy. Conclusion: Multiple PTK procedures can be performed safely with improved visual acuity in grafts without compromising graft survival.

Keratoglobus: An experience at a tertiary eye care center in India.

Context: This study was carried out as a part of an internal audit and is the largest series of patients having keratoglobus, published in the literature. Poor visual acuity of the patients indicates the blinding nature of the disease. Aims: We report our experience with patients having keratoglobus at a tertiary eye care center in India. Settings and Design: Retrospective study. Materials and Methods: We analyzed adults and pediatric patients (<16 years) with keratoglobus, seen during 2008–2012. The age, gender, consanguinity, presenting ocular signs, ocular and systemic associations, visual acuity, corneal topography, and surgeries were documented. Results: Forty‑eight patients (mean age 22 ± 15 years, 31 males) having keratoglobus were analyzed. 21 patients (42 eyes) were <16 years. Twelve eyes (16 events) had positive history of trauma. The presenting clinical signs were corneal scars/scars of tear repair (15 eyes), hydrops, healed and acute (14 eyes) and corneal or globe rupture (9 eyes). Best‑corrected visual acuity was >20/40 in 6/42 (14.3%) pediatric eyes and 15/53 (28.30%) adults. Visual acuity ranging from counting of fingers to no light perception was noted in 20/53 (37.74%) adults and 21/42 (50%) pediatric patients; 13/20 (65%) with blue sclera and 8/22 eyes (36.37%) without blue sclera. Vernal keratoconjunctivitis was present in one pediatric patient. Choroidal osteoma, retinitis pigmentosa, and retinal detachment were present in adults. Surgeries performed were corneal tear repair (5 eyes), tissue adhesive application (2 eyes), descematopexy (4 eyes) and penetrating keratoplasty (PK ‑ 8 eyes: Three had post‑PK glaucoma, graft failure‑one eye, 4 patients wore scleral lens ‑ prosthetic replacement of the ocular surface ecosystem). Conclusions: About 50% of pediatric eyes (65% having blue sclera) had no functional vision. Trivial trauma was responsible for corneal rupture indicating need for protective glasses. About 50% patients had post‑PK glaucoma though grafts were clear.

Oral epithelial cells transplanted on to corneal surface tend to adapt to the ocular phenotype.

To understand the response of oral epithelial cells, transplanted on corneal surface to the ocular cues in vivo. The corneal bu􀄴 on obtained after penetrating keratoplasty (PK) of an eye of a patient with total limbal stem cell defi ciency (LSCD), previously treated with cultured oral mucosal epithelial transplantation (COMET) was examined by immunohistochemistry for the expression of keratins, p63, p75, PAX6, Ki-67, CD31, and CD34. COMET followed by optical-PK has improved visual acuity to 20/40 and rendered a stable ocular surface. The excised corneal tissue showed the presence of stratifi ed epithelium with vasculatures. The epithelial cells of the corneal bu􀄴 on expressed K3, K19, Ki- 67, p63, p75 and the cornea-specifi c PAX6 and K12. This study confi rms that the oral cells, transplanted to corneal surface, survive and stably reconstruct the ocular surface. They maintain their stemness at the ectopic site and acquire some of the corneal epithelial-like characters.

Transforming ocular surface stem cell research into successful clinical practice.

It has only been a quarter of a century since the discovery of adult stem cells at the human corneo-scleral limbus. These limbal stem cells are responsible for generating a constant and unending supply of corneal epithelial cells throughout life, thus maintaining a stable and uniformly refractive corneal surface. Establishing this hitherto unknown association between ocular surface disease and limbal dysfunction helped usher in therapeutic approaches that successfully addressed blinding conditions such as ocular burns, which were previously considered incurable. Subsequent advances in ocular surface biology through basic science research have translated into innovations that have made the surgical technique of limbal stem cell transplantation simpler and more predictable. This review recapitulates the basic biology of the limbus and the rationale and principles of limbal stem cell transplantation in ocular surface disease. An evidence-based algorithm is presented, which is tailored to clinical considerations such as laterality of affl iction, severity of limbal damage and concurrent need for other procedures. Additionally, novel fi ndings in the form of factors infl uencing the survival and function of limbal stem cells aft er transplantation and the possibility of substituting limbal cells with epithelial stem cells of other lineages is also discussed. Finally this review focuses on the future directions in which both basic science and clinical research in this fi eld is headed.

Demographic and clinical profile of vernal keratoconjunctivitis at a tertiary eye care center in India.

Purpose: To study the demographic and clinical profile of patients with vernal keratoconjunctivitis (VKC) at a tertiary eye care center in India. Materials and Methods: Retrospective chart analysis of 468 patients of VKC seen from January 2006 to December 2006. Results: Mean age at presentation was 12 years. Majority of the patients had mixed pattern disease (72%). Chronic perennial disease was seen in 36% patients. Personal or family history of allergies was noted in 5% patients. Severe disease based on clinical grading was present in 37% patients. Moderate to severe vision loss was seen in 12% of total population. Persistent disease beyond 20 years of age was found in 12% patients. VKC‑related complications such as corneal scarring (11%), shield ulcer (3%), keratoconus (6%), and limbal stem cell deficiency (1.2%) were seen. Treatment‑related complications like corticosteroid‑induced cataract and glaucoma were seen in 6% and 4% of patients, respectively. Conclusion: Clinical pattern of VKC seen in the tropical climate of India is essentially similar to that seen in other tropical countries. Few distinct features that we noted represent chronic perennial disease, low association with atopy, and higher propensity for disease and treatment‑related complications.

Surgical management in patient with uveitis.

Surgery in the management of uveitis can be divided based on indication: either for therapeutic or can be for diagnostic purposes or to manage complications. The commonest indications include: Visual rehabilitation: surgery for removal of cataract, band keratopathy, corneal scars, pupillary membranes, removal of dense vitreous membranes, management of complications: anti-glaucoma surgery, vitreous hemorrhage, retinal detachment and chronic hypotony and diagnostic: aqueous tap, vitreous biopsy, tissue biopsy (iris, choroid). In this review, we shall describe the surgical technique for visual rehabilitation and for management of complications.

Coculture of autologous limbal and conjunctival epithelial cells to treat severe ocular surface disorders: Long-term survival analysis.

Background: Cultivated limbal epithelium for reconstruction of corneal surface is a well-established procedure; however, it is not adequate for damage which also extensively involves the conjunctiva. In severe cases of ocular surface damage that warrant additional conjunctival transplantation apart from cultivated limbal stem cell transplantation, we describe the long-term survival of a novel method of cocultivating autologous limbal and conjunctival epithelium on a single substrate. Materials and Methods: Forty eyes of 39 patients with severe limbal stem cell deficiency and conjunctival scarring or symblepharon underwent transplantation of autologous cocultivated epithelium on human amniotic membrane. A ring barrier was used to segregate the central limbal and peripheral conjunctival epithelia in vitro. Patients were followed up at regular intervals to assess stability of the ocular surface, defined by absence of conjunctivalization into the central 4 mm of the cornea and absence of diffuse fluorescein staining. Penetrating keratoplasty (PKP) was subsequently performed, where indicated, in patients with surface stability. Results: The cumulative survival probability was 60% at 1 year and 45% at 4 years by Kaplan–Meier analysis (mean follow-up duration: 33 ± 29 months, range: 1–87 months). Best-corrected visual acuity improved to greater than 20/200 in 38% eyes at the last follow-up, compared with 5% eyes before surgery. Immunohistochemistry in five of the corneal buttons excised for PKP showed an epithelial phenotype similar to cornea in all five. Conclusions: Synchronous use of cultured limbal and conjunctival epithelium offers a feasible alternative and a simpler one-step surgical approach to treat severe ocular surface disorders involving limbus and conjunctiva.

Growth of the human lens in the Indian adult population: Preliminary observations.

Context: The eye lens grows throughout life by the addition of new cells inside the surrounding capsule. How this growth affects the properties of the lens is essential for understanding disorders such as cataract and presbyopia. Aims: To examine growth of the human lens in the Indian population and compare this with the growth in Western populations by measuring in vitro dimensions together with wet and dry weights. Settings and Design: The study was conducted at the research wing of a tertiary eye care center in South India and the study design was prospective. Materials and Methods: Lenses were removed from eye bank eyes and their dimensions measured with a digital caliper. They were then carefully blotted dry and weighed before being placed in 5% buffered formalin. After 1 week fixation, the lenses were dried at 80 °C until constant weight was achieved. The constant weight was noted as the dry weight of the lens. Statistical Analysis Used: Lens parameters were analyzed as a function of age using linear and logarithmic regression methods. Results: Data were obtained for 251 lenses, aged 16–93 years, within a median postmortem time of 22 h. Both wet and dry weights increased linearly at 1.24 and 0.44 mg/year, respectively, throughout adult life. The dimensions also increased continuously throughout this time. Conclusions: Over the age range examined, lens growth in the Indian population is very similar to that in Western populations.

Short-term outcome of Boston Type 1 keratoprosthesis for bilateral limbal stem cell deficiency.

This study reports the short-term functional and anatomical outcome of Boston Type 1 keratoprosthesis (Boston Kpro) implantation for bilateral limbal stem cell deficiency (LCSD). Retrospective analysis was done on eight eyes of eight patients who underwent Boston Kpro implantation between July 2009 and October 2009. The best corrected visual acuity (BCVA) and slit-lamp biomicroscopy findings were assessed at 1, 3 and 6 months postoperatively. All eight eyes retained the prosthesis. BCVA of 20/40 or better was achieved in 8, 6, and 5 eyes at 1, 3, and 6 months, respectively, postoperatively. One patient each developed epithelial defect, sterile stromal melt and fungal keratitis in the late postoperative period associated with antecedent loss of the soft contact lens from the eye. Boston Kpro has good short-term visual and anatomical outcome in patients with bilateral LSCD, provided compliance with postoperative care can be ensured.

Phototherapeutic keratectomy.

Phototherapeutic keratectomy (PTK) is done regularly for anterior corneal diseases such as corneal dystrophies, corneal degenerations, scars, and band-shaped keratopathy. The various indications include both therapeutic and visual. The aim of this article is to discuss the therapeutic indications for PTK, the specific technique pertaining to a specific etiology, the various other procedures like amniotic membrane graft combined with PTK or PTK being done for recurrences in the grafts, and PTK done before cataract surgery when the anterior corneal pathology coexists with the cataract. Post PTK management such as healing of an epithelial defect, use of steroids in the post PTK period, recurrences of primary disease pathology, and infections, will be discussed. Methods of literature search: A Medline search was carried out for articles in the English language, with the keywords, phototherapeutic keratectomy, band-shaped keratopathy, spheroidal degeneration, scars, bullous keratopathy, and corneal dystrophy. The relevant references are mentioned here.

Late occurrence of granular dystrophy in bilateral keratoconus: Penetrating keratoplasty and long-term follow-up.

We report a rare case of keratoconus with granular dystrophy with a follow-up of two decades, documenting the sequential presentation of two diseases confirmed by histology and genetic studies. A 13-year-old boy was diagnosed in 1988 with keratoconus in both eyes (BE) based on slit-lamp biomicroscopy findings of corneal ectasia in BE accompanied by Fleischer's ring, Vogt's striae, a small, old, healed hydrops. The left eye (LE) had central corneal thinning and scar in the central area involving the mid and posterior stroma secondary to healed hydrops. Penetrating keratoplasty (PKP) was advised. The boy was lost to follow-up till 1991 and presented with white, dot-like opacities in the central cornea in the RE only, suggestive of granular corneal dystrophy. Similar findings of white, dot-like opacities were noted in the LE in 1995 and the patient subsequently underwent PKP in BE. Histopathology of corneal buttons confirmed the presence of patchy, crystal-like orange deposits, which stained bright red with Masson's trichrome. Mutational analysis of the TGFBI gene in patient's DNA revealed a heterozygous mutation corresponding to a change in Arg555Trp in the keratoepithelin protein. Granular dystrophy recurred after 8 years in the RE.

Boston ocular surface prosthesis: An Indian experience.

Context: Boston ocular surface prosthesis (BOSP) is a scleral contact lens used in the management of patients who are rigid gas permeable (RGP) failures as with corneal ectasias such as keratoconus and in those patients who have ocular surface disease such as Stevens–Johnson syndrome (SJS). Aim: To report utilization of BOSP in a tertiary eye care center in India. Materials and Methods: We retrospectively reviewed charts of 32 patients who received BOSP from July 2008 to May 2009. Indications for fitting these lenses, improvement in visual acuity (VA) before and after lens fitting and relief of symptoms of pain and photophobia were noted. Paired t-test was used for statistical analysis using SPSS version 16.0 for Windows. Results: Thirty-two patients (43 eyes) received these lenses. These consisted of 23 eyes of 17 patients who failed RGP trials for irregular astigmatism and corneal ectasia such as keratoconus and post radial keratotomy and scar and 20 eyes of 15 patients with SJS. Mean age of RGP failures was 27.94 years. Pre- and post-BOSP wear mean LogMAR VA was 1.13 and 0.29, respectively, in RGP failures. The P value was statistically significant (P < 0.001). In patients with SJS, LogMAR VA was 0.84 ± 0.92 before and 0.56 ± 0.89 after lens wear. The P value was statistically significant (P < 0.001). VA improved by >2 lines in 7/20 eyes (35%) with SJS, with improvement in symptoms. Conclusion: BOSP improves VA in patients who have irregular astigmatism as in ectasias and RGP failures and improves vision and symptoms in patients with SJS.

Amniotic membrane transplantation: a review of current indications in the management of ophthalmic disorders.

Amniotic membrane transplantation is currently being used for a continuously widening spectrum of ophthalmic indications. It has gained widespread attention as an effective method of reconstruction of the ocular surface. Amniotic membrane has a unique combination of properties, including the facilitation of migration of epithelial cells, the reinforcement of basal cellular adhesion and the encouragement of epithelial differentiation. Its ability to modulate stromal scarring and its anti-inflammatory activity has led to its use in the treatment of ocular surface pathology as well as an adjunct to limbal stem cell grafts. Amniotic membrane transplantation has been used for reconstruction of the corneal surface in the setting of persistent epithelial defects, partial limbal stem cell deficiency, bullous keratopathy and corneoscleral ulcers. It has also been used in conjunction with limbal stem cell transplantation for total limbal stem cell deficiency. Amniotic membrane grafts have been effectively used as a conjunctival substitute for reconstruction of conjunctival defects following removal of pterygia, conjunctival lesions and symblephara. More recently, amniotic membrane has been used as a substrate for ex vivo cultivation of limbal, corneal and conjunctival epithelial cells. This article reviews the current literature on the applications of amniotic membrane transplantation and its outcome in various ophthalmic conditions.

Expansive mortar-induced ocular injury.

We describe here a case of bilateral chemical injury (with an expansive mortar which is being used in recent times to cut the rocks). On examination limbal ischemia was more in the left eye (9 clock hours) than the right eye (2 clock hours). The case was managed by bilateral removal of foreign bodies, along with conjunctival resection and amniotic membrane transplantation in the left eye. At six-month follow-up, patient had best corrected visual acuity of 20/30 and 20/60 in the right and left eyes respectively. Since this being an occupational hazard, proper eye protection gear should be used by persons using this expansive mortar.

Clinical outcome of autologous cultivated limbal epithelium transplantation.

PURPOSE: To report the clinical outcome of autologous cultivated limbal epithelial transplantation. METHODS: Eighty-six patients' records and their clinical photographs were reviewed for demographics, primary etiology, type of limbal transplantation, ocular surface stability, visual acuity, final outcome and possible factors affecting outcome and complications. RESULTS: Eighty-eight eyes of 86 patients with limbal stem cell deficiency (LSCD) underwent autologous cultivated limbal epithelium transplantation between March 2001 and May 2003, with a mean follow-up of 18.3 months. The etiology of LSCD was alkali burns in 64% patients. Sixty-one eyes had total LSCD. Thirty-two of the 88 eyes had undergone amniotic membrane transplantation and 10 eyes had previously undergone limbal transplantation with unfavorable outcome. Nineteen eyes underwent penetrating keratoplasty, of which 11 grafts survived at the final follow-up. Finally, 57 eyes (73.1%, 95% CI: 63.3-82.9) had a successful outcome with a stable ocular surface without conjunctivalization, 21 eyes (26.9%, 95%CI: 17.1-36.7) were considered failures and 10 patients were lost to follow-up. CONCLUSION: LSCD can be successfully treated by autologous cultivated limbal epithelium transplantation in majority of the cases.

Early results of penetrating keratoplasty following limbal stem cell transplantation.

PURPOSE: To describe the early results of penetrating keratoplasty (PKP) in patients who had earlier received limbal transplantation (LT). METHODS: Prospective, non-comparative interventional case series comprising of four patients with limbal stem cell deficiency (LSCD) due to chemical injury (Cases 1, 2, 4) and xeroderma pigmentosum (Case 3). Cadaveric kerato-limbal allografts or living-related conjunctival-limbal allografts were done in four eyes followed by PKP for visual rehabilitation 3-4.5 months later. The following details were noted: demographics, primary aetiology, type of limbal transplant (cadaveric or living-related), immunosuppression, vision and ocular surface stability before and after LT and PKP, surgical complications and outcome of PKP. RESULTS: Three eyes received living-related conjunctival-limbal allotransplantation and one received cadaveric kerato-limbal allograft. Duration of follow up after PKP ranged from 4 to 11 months. Visual acuity improved in the early postoperative period in all patients but reduced in 2 due to endothelial rejection and after trans-scleral cyclophotocoagulation for medically uncontrolled glaucoma. The ocular surface remained stable in all patients. All patients were started on immunosuppression on the first postoperative day. This was continued till the last follow-up visit. Post-PKP complications were punctate epithelial keratopathy, corneal allograft rejection and secondary glaucoma (one patient each). CONCLUSION: Satisfactory visual rehabilitation is possible after PKP following LT without compromising ocular surface stability. However, a prolonged and close follow-up is warranted to avert complications.

Amniotic membrane transplantation for reconstruction of corneal epithelial surface in cases of partial limbal stem cell deficiency.

PURPOSE: To assess the efficacy of amniotic membrane for treatment of partial limbal stem cell deficiency (LSCD). METHODS: Medical records of four patients with partial LSCD who underwent pannus resection and amniotic membrane transplantation (AMT) were reviewed for ocular surface stability and improvement in visual acuity. Clinico-histopathological correlation was done with the resected pannus tissue. RESULTS: All the eyes exhibited stable corneal epithelial surface by an average of 7 weeks postoperatively with improvement in subjective symptoms. Best corrected visual acuity improved from preoperative (range: 6/9p-6/120) to postoperative (range: 6/6p-6/15) by an average of 4.5 lines on Snellen visual acuity charts. Histopathological examination of excised tissue showed features of conjunctivalisation. CONCLUSION: Amniotic membrane transplantation appears to be an effective means of reconstructing the corneal epithelial surface and for visual rehabilitation of patients with partial limbal stem cell deficiency. It may be considered as an alternative primary procedure to limbal transplantation in these cases.

Ex-vivo potential of cadaveric and fresh limbal tissues to regenerate cultured epithelium.

PURPOSE: To evaluate and compare the ex-vivo growth potential and formation of cultured corneal epithelium from residual corneo-limbal rings obtained from the operating room after penetrating keratoplasty, and fresh limbal tissues from patients undergoing routine cataract surgery. METHODS: With the approval of the Institutional Review Board and informed consent from patients, 1-2 mm of limbal tissues from 15 patients and 31 tissues from the cadaveric limbal ring preserved in MK medium (16 tissues) and Optisol (15 tissues) were used for the study. Donor data included age, time lapse between death and collection, collection and preservation and preservation and culture. Tiny bits of the limbal tissue were explanted on the de-epithelialised human amniotic membrane prepared following standard guidelines, and cultured using Human Corneal Epithelial cell medium. Radial growth from the explant was observed and measured by phase contrast microscopy over 2-4 weeks. After adequate confluent growth, whole mount preparation of the membrane was made and stained with haematoxylin and eosin. Part of the membrane was fixed in formalin and processed for routine histologic examination. The sections were stained with haematoxylin and eosin. RESULTS: Forty-six tissues were evaluated from 42 eyes (15 from patients, 31 from cadaveric eyes) with a mean age of 55.3 years +/- 21.23 years (range 18 years - 110 years). The growth pattern observed was similar in all the positive cases with clusters of cells budding from the explant over 24-72 hours, and subsequent formation of a monolayer over the next 2-3 weeks. The stained whole mount preparation showed a radial growth of cells around explants with diameter ranging from 5 to 16mm. Histologic evaluation of the membrane confirmed the growth of 2-3 cell-layered epithelium over the amniotic membrane. Cultivated epithelium around explant cell cultures was observed in 100% (15/15) of limbal tissue obtained from patients, as against 56% (9/16) of MK medium preserved tissues and 46.7% (7/15) of Optisol preserved tissues. This was statistically significant (P=0.0131) There was no significant statistical difference in the growth properties, i.e, the mean percentage of fragments showing growth (P=0.229) or the mean diameter of growth (P=0.479) in the cultures obtained from fresh and preserved tissues. The time lapse at various stages between death and utilisation and donor age had no significant influence on the growth potential of the limbal tissues. CONCLUSION: The potential for generating cultured corneal epithelium from fresh limbal tissues obtained from living subjects is higher than that observed with preserved tissues. It would also be worthwhile to address the factors that could further enhance the proliferative potential of the cadaveric tissues obtained from eye banks.