Hepatitis C and ocular surface disease

PURPOSE: To assess the frequency of changes in the ocular surface and the presence of hepatitis C virus (HCV) in tear samples of patients with chronic HCV infection. DESIGN: Prospective, nonrandomized, clinical, interdisciplinary, single-center study. METHODS: Seventy-one patients with previously untreated chronic HCV infection and a control group consisting of 66 patients without systemic HCV infection were enrolled in the trial. The patients with HCV infection were screened for ocular symptoms, visual acuity, and ocular changes. Tear production was measured by the Jones test. Conjunctival impression cytologic analysis was performed. The presence of HCV ribonucleic acid (RNA) in tear and blood samples was determined by quantitative polymerase chain reaction. RESULTS: On examination, systemic HCV infection was present for a median of 30 months. Fifty percent of all HCV patients showed a decrease in tear production measured by the Jones test. Apart from epithelial changes related to dry eye syndrome in 12 patients, two patients presented mild peripheral corneal thinning. Polymerase chain reaction analysis detected HCV RNA in five (10%) of 52 tear samples. HCV RNA levels in tear samples (mean, 1.0 x 10(4) copies/ml) were considerably lower than in blood samples (mean, 5.3 x 10(5) copies/ml). CONCLUSIONS: Dry eye syndrome is the most frequently observed ocular feature in HCV infection. Patients with HCV infection (age range, 21 to 60 years) compared with the controls had a significant lower tear production (P = .05). The presence of HCV RNA in 10% of tear samples emphasizes the potential risk of viral transmission through tears.     

Conjunctival grafting for ocular surface disease

The procedure of transplanting healthy conjunctiva onto eyes with damaged ocular surface epithelium was first described by Thoft in 1977. Today, conjunctival autografting is widely used in pterygium surgery and has been shown to be both safe and effective in reducing pterygium recurrence. Several randomized, controlled, clinical trials have been reported in the literature, and conjunctival autografting is now recognized to have an efficacy equal to that of such adjunct therapies as beta-irradiation and mitomycin C, and yet it is safer than these treatments. Recent modifications of the conjunctival autograft include the conjunctival rotation autograft and the inferior conjunctival transposition flap, both of which have been reported to be associated with low rates of recurrence. With the discovery of the role of limbal stem cells in the maintenance and stability of the corneal surface, recent forms of ocular surface transplantation that have supplanted Thoft's conjunctival transplantation procedure include limbal autograft transplantation and limbal allograft transplantation. In addition, the adjunct use of human amniotic membrane in these ocular surface transplantation procedures has improved success and survival rates in the management of ocular surface disease, which still presents significant challenges to clinicians today.     

眼表疾病研究进展

眼表疾病是常见的眼科疾病，可以引起视觉障碍。眼表疾病的研究是近年来眼科界发展较快、成果较多的领域之一。本文对近年来眼表疾病研究的新进展进行综述。     

Toll-like receptors in ocular surface disease

The ability of the ocular surface to mount an immune response is in part attributed to a family of proteins called toll-like receptors (TLRs). The latter are evolutionary conserved receptors that recognize and respond to various microbes and endogenous ligands. In addition to their recognition function, TLR activation triggers a complex signal transduction cascade that induces the production of inflammatory cytokines and co-stimulatory molecules, thus initiating innate and adaptive immunity. Toll-like receptor expression at the ocular surface is modulated during infection (e.g. Herpes simplex, bacterial keratitis and fungal keratitis) as well as during various inflammatory conditions (allergic conjunctivitis and dry-eye syndrome). Here recent findings regarding TLR expression and their involvement in various ocular surface diseases are discussed.     

新鲜羊膜移植治疗眼表疾病的临床观察

目的:探讨新鲜羊膜移植治疗眼表疾病的可行性并对其疗效进行评价。方法:选择本院就诊的翼状胬肉40例(50眼),广泛睑球粘连2例(4眼),急性碱烧伤5例(9眼)、结膜乳头状瘤3例(6眼)共50例(69眼)。分别进行羊膜移植术。术后观察视力、裂隙灯检查角膜上皮修复情况,羊膜成活情况及新生血管长入情况。随访观察3～24mo。结果:69眼均未发生新鲜羊膜植片的急性排斥反应和感染现象。急性严重碱烧伤5例抢救成功。视力有不同程度提高。睑球粘连2例(4眼)恢复了眼球运动并提高了视力。40例(50眼)翼状胬肉有4眼复发,复发率为8%,与其它2种术式相比本法复发率较低。结论:新鲜羊膜移植治疗翼状胬肉能有效地降低复发率。治疗化学伤能减轻炎症、减少新生血管形成,减少并发症,为眼表重建提供了一种有效的生物材料。     

Clinical management of severe ocular surface disease

Severe ocular surface diseases, such as Stevens-Johnson syndrome, ocular cicatricial pemphigoid or severe ocular burns may result in a significant loss of corneal stem cells, eventually leading to vision impairment or even corneal blindness. In case of unilateral involvement, limbal autografting, by means of transplanting limbal stem cells from the healthy fellow eye, has proved to be an effective procedure for restoring the integrity of the ocular surface. Limbal allografts may be performed in patients with bilateral disease, however, systemic immunosuppression is mandatory in these cases, with a long-term outcome that is frequently reduced compared to limbal autografts due to acute or chronic graft rejection. In recent years, amniotic membrane transplantation has been successfully employed as an additional tool in ocular surface reconstruction. The AlphaCor synthetic cornea, which is made of flexible acrylic may be considered as an alternative in patients with repeated corneal graft failures. Both limbal transplantation and the AlphaCor have been shown to be effective in eyes with an adequate tear film, but are most likely to fail in severe dry eyes or in patients with cicatrising diseases. Such conditions are the domain of keratoprostheses (KPros) with rigid optics, which certainly can be considered as the 'last resort' to restore vision in patients with profound corneal blindness not amenable to conventional corneal and limbal grafting. The osteo-odonto-keratoprosthesis according to Strampelli and modified by Falcinelli makes use of a "biological" support consisting of a longitudinal section of one of the patient's teeth that is also supported by the surrounding alveolar bone tissue. Compared to other devices favourable long-term results have been reported. In patients lacking any usable teeth, implantation of a keratoprosthesis with haptics made of Dacron (Pintucci-KPro) or tibial bone (Temprano-KPro) might be considered.     

Adnexal surgery for severe ocular surface disease

Secondary causes of ocular surface disease are-to a large extent-due to disorders of the ocular adnexae. The main pathomechanisms involved include exposure, abrasion and malnutrition, resulting from a multitude of disorders such as ec- or entropion (e.g. in cicatrizing conjunctivitis), lid retraction and severe aqueous deficiency. In the presence of these problems, surgical attempts of ocular surface reconstruction frequently fail. Here we review established and evolving new techniques in the field of adnexal surgery to specifically address these problems.     

人体血清在眼表疾病中的应用

清在眼科疾病中的应用概况作综述.     

羊膜移植在眼表疾病中的应用

目的：探讨羊膜移植治疗眼表疾病的疗效，寻找有效降低翼状胬肉术后复发率的新方法。方法：对34例翼状胬肉，1例硷烧伤致睑球粘连患者进行保存羊膜移植手术，并在术后3月，6月分别取患眼部位羊膜植片进行组织细胞学检查，随访3－18月，结果：羊膜移植片生长良好，术后复发率为5．7％，无感染现象。细胞学检查表明，羊膜能够在免疫条件下成活后适应生长。结论：羊膜移植可用于治疗多种眼表疾病，尤其可以有效降低翼状胬肉术后复发率，是一种能够重建正常眼表，值得推广的新手术。     

Imaging of vascular abnormalities in ocular surface disease

The vascular system of the ocular surface plays a central role in infectious, autoimmune, inflammatory, traumatic and neoplastic diseases. The development, application, and monitoring of treatments for vascular abnormalities depends on the in vivo analysis of the ocular surface vasculature. Until recently, ocular surface vascular imaging was confined to biomicroscopic and color photographic assessment, both limited by poor reproducibility and the inability to image lymphatic vasculature in vivo. The evolvement and clinical implementation of innovative imaging modalities including confocal microscopy, intravenous, and optical coherence tomography–based angiography now allows standardized quantitative and functional vascular assessment with potential applicability to automated analysis algorithms and diagnostics.     

Methodologies for the study of ocular surface disease

The ability to obtain reliable results from clinical trials of therapies for ocular allergic disease and dry eye disease is often limited because of inadequate control of variables, such as environment, patient life style, compliance, and individual fluctuations that occur from one assessment visit to another. The controlled allergen challenge (CAC) model of allergic conjunctivitis allows signs and symptoms of the disease to be elicited in a physiologically accurate and reproducible manner. The rigid criteria for subject selection, the controlled allergic reaction, and the standardized and quantified grading systems allow for a reproducible baseline from which statistically and clinically significant differences between formulations can be assessed. Similarly, the controlled adverse environment (CAE) model for dry eye mimics the environmental stimuli that lead to ocular surface drying. Preselected subjects have a reproducible, homogeneous baseline reaction from which the effects of various treatments can be significantly evaluated and compared. CAC and CAE provide accurate means to study highly variable and individual ocular surface disease.     

Classification of ocular surface disease. Part 1

The ocular surface consists of the lid margin, conjunctiva and cornea which together with the tear system represent a functional entity. The diagnosis of ocular surface disease can be very difficult due to the similarity of various disease entities. The classification should be made on the pathological and pathophysiological characteristics of ocular surface disease. The first part of the classification comprises diseases of the lid margin, the tear system as well as diseases of the conjunctiva. Both the clinical presentation as well as the underlying pathophysiological and pathological characteristics of the most important ocular surface diseases are reviewed.     

Deep lamellar keratoplasty in severe ocular surface disease

PURPOSE: To demonstrate the efficacy and safety of deep lamellar keratoplasty(DLKP) in the treatment of corneal opacity in severe ocular surface disease. METHODS: A total of 12 eyes of 11 patients were analyzed in this retrospective case series. The original diseases were Stevens Johnson syndrome (SJS : 3 eyes), ocular ciccatricial pemphigoid(OCP : 2 eyes), thermal burns (2 eyes), limbal deficiency due to unknown cause (2 eyes), and corneal scarring due to trachoma (3 eyes). Cases with total limbal deficiency (6 eyes) were also treated with secondary or simultaneous limbal transplantation. Cataract surgery was also performed in 4 eyes following DLKP. RESULTS: DLKP was successfully done in all cases. One case with SJS experienced an immunological rejection against the limbal graft. Two eyes with SJS eventually developed ulcers that required therapeutic penefrating keratoplasty. Visual improvement was observed in 9 out of 12 eyes, of which 2 cases maintained a corrected visual acuity of 0.1 despite conjunctivalization of the ocular surface. CONCLUSION: DLKP is an effective means to treat stromal opacity in patients with ocular surface disease.