Severe chemical eye injuries - clinical outcomes and associated socio-economic factors.

Aims: To describe clinical outcomes, management, and socio-economic impact of severe acute chemical eye injuries in a tertiary hospital. Methods: 37 patients required emergency admission to the Royal Victoria Infirmary eye ward between April 2013 and September 2015. Demographics, best corrected distance visual acuity (BCDVA), causative agent, degree of limbal stem cell deficiency (LSCD), management and socio-economic data were evaluated. Results: Mean age on admission was 34.5 years (SD 16.3; range 16-82); 30 males (81.1%); 22 bilateral (59.5%). Causative agent: alkali in 30 cases (81.1%); acid in three cases (8.1%); and unknown in four cases (10.8%). Fifteen cases (40.5%) were assaults, 12 (32.5%) work-related accidents, nine (24.3%) domestic accidents and one (2.7%) undetermined. Eleven patients (29.7%) were unemployed, 18 (48.6%) were labourers, three (8.1%) were students, three (8.1%) were retired and two (5.4%) were professionals. Mean admission time was five days (SD 3.2; range 1-12). Mean follow-up time was 170.5 days (range 1-946). Mean cost of admission was £2478 (range £274-5785). Five patients (13%; seven eyes) developed total or partial limbal stem cell deficiency, all being assaults. Conclusions: Main causative agent in our study was alkali, with young men in the working age being most frequently involved. Many patients required prolonged hospital admission and costly follow-up. The majority of cases were assaults, mostly occurring in unemployed patients. All the limbal stem cell deficiency cases were due to assaults. We believe that socio-economic factors play an important role in the cause, severity and cost of chemical eye injuries. Lay Summary: Acute chemical eye injuries have a significant and extensive impact on patients' visual function outcomes and vision-related quality of life, with consequent enormous burden to affected individuals, their families and society. We believe that by understanding the socio-economic environment, we may not only be able to enforce safety measures to tackle the increasing rate of severe chemical eye injuries in our community, but also to develop collaborative programmes with the community, educating the population on the seriousness of chemical eye injuries, and with the local authorities, trying to understand the clustering of assaults in areas and tackling the associated socio-economic risk factors, such as unemployment. Given the increasing rate of assaults using chemicals in recent times, it is also important to assess availability of adequate victim support programmes and develop good interaction with relevant local, regional and national authorities to ensure all aspects of community security service are in place to be able to address any potential deficiencies in line with police and home office guidelines. Keeping in mind that the best action plan is always prevention. However, when an ocular injury does occur it is evident that significant morbidity and visual sequelae can result and affect the socio-economic status of the victims despite our best current medical and surgical care.

Understanding Ocular Surface Inflammation in Tears Before and After Autologous Cultivated Limbal Epithelial Stem Cell Transplantation.

INTRODUCTION: We aimed to determine the expression of inflammatory cytokines in the tears of patients with unilateral total limbal stem cell deficiency (TLSCD) caused by chemical burns before and after autologous cultivated limbal epithelial stem cell transplantation (CLET). METHODS: Tear samples were collected from both eyes of 23 patients with unilateral TLSCD and 11 healthy controls, at fixed timepoints before and after CLET. Dissolved molecules were extracted from Schirmer's strips using a standardised method and analysed on an array plate of ten inflammatory cytokines (V-Plex Proinflammatory Panel 1 Human Kit, MSD). RESULTS: IL1ß expression was significantly elevated in the TLSCD eye compared with the unaffected eye at baseline (p < 0.0001) but decreased to normal 3 months post-CLET (p = 0.22). IL6 and IL8 were unaffected at baseline but significantly elevated in the TLSCD eyes at 1 month post-CLET (p = 0.001 and p < 0.0001, respectively). IL6 returned to normal at 3 months and IL8 at 6 months post-CLET. There was a significant renewed increase in IL1ß, IL6 and IL8 expression at 12 months post-CLET (p < 0.0001, p = 0.0001 and p = 0.0003, respectively). IFNγ, IL10 and IL12p70 expression were significantly reduced in both eyes of patients with unilateral TLSCD at all timepoints. CONCLUSION: IL1ß is a specific marker of inflammation in TLSCD eyes that could be therapeutically targeted pre-CLET to improve stem cell engraftment. At 12 months post-CLET the spike in levels of IL1ß, IL6 and IL8 coincides with cessation of topical steroids, suggesting ongoing subclinical inflammation. We therefore recommend not discontinuing topical steroid treatment in cases where penetrating keratoplasty is indicated; however, further investigation is needed to ascertain this. TRIAL REGISTRATION: European Union Drug Regulating Authorities Clinical Trials Database (EuDRACT 2011-000608-16); ISRCTN (International Standard Randomised Controlled Trial Number (isrctn51772481).

Conjunctival Biopsy Site in Mucous Membrane Pemphigoid.

PURPOSE: To investigate if there is an association between the location of the conjunctival biopsy site (lesional, perilesional, or nonaffected) and the result of the direct immunofluorescence (DIF) test in patients with suspected mucous membrane pemphigoid (MMP) involving the ocular surface. DESIGN: Retrospective case series. METHODS: Records of patients with clinically suspected ocular MMP were reviewed to determine the location of the conjunctival biopsy. Conjunctival biopsy locations were defined as "lesional," "perilesional," and "nonaffected" conjunctiva. The DIF was considered positive when there was deposition of at least 1 of either IgM, IgG, IgA, or C3 at the basement membrane of the specimen; nondiagnostic when only fibrinogen was found at the same location; and negative when none of these features were present. RESULTS: The records of 41 patients were analyzed. Of these, 32 were eligible to be included in the study. Biopsies were lesional in 22% of cases (7/32), perilesional in 22% (7/32), and from nonaffected conjunctiva in 56% (18/32). DIF results were positive in 14% of lesional biopsies, in 86% of perilesional biopsies, and in 17% of those from nonaffected conjunctiva (P = .003). Perilesional biopsies gave higher positive DIF than lesional biopsies (P = .029). CONCLUSIONS: Perilesional conjunctival biopsies are associated with an increase in positive DIF results. These results support the need to sample perilesional conjunctival tissue in patients with suspected MMP.

A case of ocular cystinosis associated with two potentially severe CTNS mutations.

BACKGROUND: Ocular cystinosis is a rare autosomal recessive disorder caused by one severe and one mild mutation in the CTNS gene. It is characterised by cystine deposition within the cornea and conjunctiva however, the kidneys are not affected. We report a case of ocular cystinosis caused by two potentially severe CTNS mutations and discuss the possible mechanism of renal sparing. METHODS: This is an observational case report of the proband and her unaffected relatives. All subjects underwent ophthalmic examination, whilst in the proband, In vivo laser scanning confocal microscopy was used to demonstrate cystine crystals within her corneas and conjunctiva. Genetic diagnosis was confirmed by DNA sequencing of the proband and the segregation of the mutations was established in her relatives. RT-PCR of leukocyte RNA was undertaken to determine if aberrant splicing of the CTNS gene was taking place Results: The proband was found to have cystine crystals limited to the anterior corneal stroma and the conjunctiva. Sequencing of the proband's CTNS gene found her to be a compound heterozygote for a 27bp deletion in exon8/intron 8 (c.559_561 + 24del) and a novel c.635C>T variant in exon 9 that is predicted be pathogenic and to result in the substitution of alanine with valine at amino acid position 212 (p.Ala212Val), which is within the 3rd transmembrane spanning domain of the CTNS protein. Examination of the proband's leukocyte RNA failed to demonstrate any aberrant CTNS gene splicing. CONCLUSION: We present a case of ocular cystinosis caused by two potentially severe CTNS gene mutations. The lack of renal involvement may be due to localised (ocular) aberrant CTNS RNA splicing.

Outcomes of Penetrating Keratoplasty Following Autologous Cultivated Limbal Epithelial Stem Cell Transplantation.

The purpose of this study is to investigate the outcomes of penetrating keratoplasty (PKP) following autologous cultivated limbal epithelial stem cell transplantation (CLET). A prospective, single center, interventional cohort study investigating patients with unilateral total limbal stem cell deficiency (LSCD) treated with CLET who underwent PKP. Patients with confirmed corneal re-epithelialization > 6 months post-CLET, and with best-corrected visual acuity (BCVA) <0.3 logMAR were offered PKP. CLET survival assessed by slit lamp, corneal impression cytology (CIC), and in vivo confocal microscopy. Confirmation of corneal re-epithelialization by histological and immunocytochemical (ICC) examination of trephined corneal buttons. Mean change in best-corrected visual acuity (logMAR) following PKP and PKP survival at 12 months were calculated. Twenty patients underwent PKP. Mean time of PKP was 19 months (range 11-41 months, SD 7.26) post-CLET. Median follow-up time post-PKP was 15 months (range 1-32, SD 10.2). CIC and ICC of all corneas confirmed corneal re-epithelialization before PKP. Mean pre-PKP BCVA was 1.46 (range 0.3-2.7, SD 0.94) improving to a mean post-PKP BCVA of 0.74 (range 0-2.7, SD 0.87); mean improvement in BCVA post-PKP of 36 letters (95% CI 15.0-57.1, p = .002). Kaplan-Meier mean graft survival was 90.9% (95% CI 50.8-98.7) at 12 months. We recommend a two-stage approach with CLET followed by PKP >12 months later. Patients experienced a significant improvement in BCVA following PKP. PKP did not have a detrimental effect on CLET survival. PKP survival post-CLET is better than that reported for high risk PKP. Stem Cells 2018;36:925-931.

Corneal Neurotization for Neurotrophic Keratopathy: Clinical Outcomes and In Vivo Confocal Microscopic and Histopathological Findings.

PURPOSE: To describe the long-term outcomes and in vivo confocal microscopic (IVCM) and histopathological findings after corneal neurotization surgery. METHODS: We included 2 patients who underwent corneal neurotization surgery for severe unilateral neurotrophic keratopathy secondary to cerebellopontine angle meningioma. Corneal sensation was measured using the Cochet-Bonnet esthesiometer (CBE) (0-60 mm). IVCM was performed using the Heidelberg HRT3 Rostock Corneal Module. Histopathological examination was performed on the excised corneoscleral disc of patient 2. RESULTS: In patient 1, corneal sensation improved from 0 mm preoperatively to 60 mm in all 4 quadrants by 2 years postoperatively and was maintained at 5 years postoperatively with identifiable subbasal and stromal corneal nerves on IVCM. In patient 2, corneal sensation improved from 0 mm preoperatively to 10 mm in 3 quadrants (9 months postoperatively) but returned to 0 mm in all quadrants by 2 years postoperatively. IVCM failed to identify any subbasal and stromal corneal nerves. At 5 years postoperatively, evisceration was performed to ameliorate uncontrolled and persistent ocular pain and poor cosmesis. Histopathological examination of the excised corneoscleral disc confirmed the presence of normal-sized, central corneal stromal nerve fascicles but without direct continuity with the transplanted perilimbal nerve bundles. CONCLUSIONS: Our study elucidates the mechanism of corneal neurotization surgery at a cellular level. Although only 1 patient achieved long-term improvement in corneal sensation postoperatively, the findings on IVCM and histopathological examination suggest that partial regeneration/maintenance of corneal nerves after corneal neurotization surgery is likely attributed to the paracrine neurotrophic support, instead of direct sprouting, from the perilimbal transplanted nerve fascicles.

An important role for adenine, cholera toxin, hydrocortisone and triiodothyronine in the proliferation, self-renewal and differentiation of limbal stem cells in vitro.

The cornea is a self-renewing tissue located at the front of the eye. Its transparency is essential for allowing light to focus onto the retina for visual perception. The continuous renewal of corneal epithelium is supported by limbal stem cells (LSCs) which are located in the border region between conjunctiva and cornea known as the limbus. Ex vivo expansion of LSCs has been successfully applied in the last two decades to treat patients with limbal stem cell deficiency (LSCD). Various methods have been used for their expansion, yet the most widely used culture media contains a number of ingredients derived from animal sources which may compromise the safety profile of human LSC transplantation. In this study we sought to understand the role of these components namely adenine, cholera toxin, hydrocortisone and triiodothyronine with the aim of re-defining a safe and GMP compatible minimal media for the ex vivo expansion of LSCs on human amniotic membrane. Our data suggest that all four components play a critical role in maintaining LSC proliferation and promoting LSC self-renewal. However removal of adenine and triiodothyronine had a more profound impact and led to LSC differentiation and loss of viability respectively, suggesting their essential role for ex vivo expansion of LSCs. Replacement of each of the components with GMP-grade reagents resulted in equal growth to non-GMP grade media, however an enhanced differentiation of LSCs was observed, suggesting that additional combinations of GMP grade reagents need to be tested to achieve similar or better level of LSC maintenance in the same manner as the traditional LSC media.

Urrets-Zavalia syndrome following penetrating keratoplasty for keratoconus.

BACKGROUND: Urrets-Zavalia syndrome (UZS) consists of a fixed dilated pupil associated with iris atrophy. It is a poorly understood complication following penetrating keratoplasty (PKP) for keratoconus (KC). In this work, we aim to establish the incidence, visual outcomes, and an understanding of UZS. METHODS: This was a retrospective single-center study in a tertiary eye service in the United Kingdom of consecutive patients with UZS following PKP for KC in a 10-year period. Post-operative complications, including raised intraocular pressure (IOP), were recorded. UZS patients and age-matched control patients who had undergone PKP for KC without developing UZS attended a comprehensive clinical assessment. Anterior segment indocyanine green (ICG) angiography assessed iris perfusion. RESULTS: The incidence of UZS was 16.2 %. There was no difference in LogMAR VA or Pelli-Robson contrast sensitivity between groups. There was higher first-day post-operative IOP in UZS (p = 0.02). UZS patients had increased pupil size (p = 0.09) with reduced response to pilocarpine 2 % (p < 0.001). ICG angiography revealed delayed/reduced iris vasculature filling in UZS compared with normal filling patterns of controls. CONCLUSIONS: Elevated post-operative IOP within 24 h was a significant factor in the development of UZS. Visual function in UZS patients was unaffected. UZS patients developed longstanding mydriasis with reduced reactivity to topical pilocarpine 2 %. ICG angiography confirmed iris vessel ischemia; supporting the theory that iris ischemia resulting from occlusion of iris root vessels due to elevated IOP causes UZS. We advocate rigorous intraoperative management of ocular viscoelastic devices and aggressive postoperative IOP control in patients undergoing PKP for KC.