Amniotic membrane transplant with superficial keratectomy in superficial corneal degenerations: efficacy in a rural population of north India

Anterior segment optical coherence tomography for superficial keratectomy

PURPOSE

To report the use of anterior segment optical coherence tomography (AS-OCT) for superficial keratectomy (SK) in anterior corneal opacity.

METHODS

The characteristics of 43 eyes (39 patients) with various lesions responsible for anterior corneal opacity were included in this retrospective non-comparative study. AS-OCT was performed on all eyes before surgery. The thickness of corneal opacity and the underlying healthy stroma were measured. SK was performed on each individual.

RESULTS

Four types of anterior corneal opacity were evaluated, including corneal degeneration (26/43), Reis-Bücklers corneal dystrophy (8/43), alkali burn (1/43) and corneal tumors (8/43). Based on AS-OCT images, all eyes showed abnormal hyper-reflective signals in the superficial cornea to less than one-third of the normal corneal thickness in the deepest corneal opacity. All 43 eyes underwent an SK procedure. In addition, 1 eye with alkali burns and 7 eyes with corneal tumors were combined with amniotic membrane transplantation. All eyes restored transparency without significant complications.

CONCLUSION

AS-OCT is a valuable method for objective preoperative and noninvasive assessments of anterior corneal opacities and is useful for guiding SK.

Combined superficial keratectomy, alcohol delamination and amniotic membrane patch with fibrin glue in Salzmann nodular degeneration

PURPOSE

To describe the outcomes of five Salzmann's Nodular Degeneration (SND) cases treated with a combination of alcohol delamination, superficial keratectomy and amniotic membrane patch with fibrin glue.

METHODS

Five patients affected by SND with significant discomfort and decreased visual acuity were evaluated with refraction, best corrected visual acuity, Break-up time test, corneal topography, Anterior Segment of Optical Coherence Tomography and images of anterior segment with a full slit lamp examination. All the patients underwent alcohol delamination of the corneal epithelium followed by superficial keratectomy to remove the subepithelial nodules. A patch of amniotic membrane was applied to all of them with a ring shape and a banana shape in two patients due to the location of the disease. A bandage contact lens was inserted. The patch was kept in place for 14 days. Another bandage contact lens was inserted for 21 days until the corneal epithelium had completely healed.

RESULTS

The surgical procedure was successful in removing the nodules in all patients. Vision was restored in all cases with a significant regularization of the corneal surface and reduction of ocular discomfort. After a 12-month follow-up, none of the patients showed recurrence of the disease.

CONCLUSIONS

Combining alcohol delamination with superficial keratectomy and amniotic membrane patch with fibrin glue is an effective procedure for the management of SND to regularize the corneal surface and avoid the recurrence of subsequent nodules. This report is the first description of the outcomes of SND cases treated with a combination of the aforementioned techniques.

Integrated analysis of microRNA expression in tears of Kazakh patients with climatic droplet keratopathy in Xinjiang, China

Climatic droplet keratopathy (CDK) is a corneal diseases, which is characterized by increased oil-like deposits on the anterior elastic lamina and anterior stromal layer. Severe CDK can even cause blindness, with no specific available treatment. Besides. CDK is poorly understood in terms of its pathogenic mechanisms. Thus, to determine potential biomarkers for CDK, we analyzed the microRNA expression profile in tear samples from CDK patients and investigated their putative roles in the pathogenesis of CDK. Herein, miRNA sequencing and following bioinformatics analysis was performed to explore the roles of their target genes in CDK. A total of 67 differentially expressed miRNAs were identified, of which 25 were upregulated and 42 were downregulated. qPCR verification showed that among the up- and down-regulated miRNAs, expression of five and six, respectively, was most significantly different.The target genes of the differentially expressed miRNAs are involved in the FoxO signaling pathway, tumor necrosis factor (TNF) signaling pathway, and steroid hormone biosynthesis. Protein-protein interaction network analyses identified 20 hub genes, including PTEN, GSK3B, and SMAD3. In conclusion, the panel of differentially expressed miRNAs identified may have potential utility as early diagnostic biomarkers for CDK. Moreover, the TNF signaling pathway is a new potential target in CDK for the development of treatments.

Superficial Keratectomy: A Review of Literature

Superficial keratectomy (SK) is the manual dissection of the superficial corneal layers (epithelium, Bowman's layer, and sometimes superficial stroma). SK is done using a surgical blade or diamond burr. Some surgeons use intraoperative mitomycin C 0.02% or amniotic membrane transplantation to improve surgical outcomes. This literature review shows that SK remains an effective method for different indications, including tissue diagnosis, excision of corneal degenerations, dystrophies, scarring, recurrent corneal erosions, and retained corneal foreign body.

Prevalence and associated factors for climatic droplet keratopathy in Kazakhs adults: a cross-sectional study in Tacheng, Xinjiang, China

Background

Investigation of the prevalence of climatic droplet keratopathy (CDK) in Tacheng, Xinjiang, China.

Methods

A total of 1030 participants, in their 40s or older, from the Kazakh ethnic group in Tacheng, were randomly sampled by stratification method. Ophthalmic examinations and surveys were carried out on these participants. Factors associated with CDK were analyzed with logistic regression models.

Results

CDK was found in 66 (6.4%; 95% confidence interval [CI]: 4.9–7.9%) Kazakh individuals.

After multiple regression model analysis, it demonstrated that age (< 0.001), exposure time (< 0.001), exposure protection (< 0.001), and vegetable intake (< 0.001) were of correlation with CDK, of which age (OR = 1.21[CI]: 1.16–1.27) and long-term outdoor exposure (OR = 2.42[CI]: 1.26–4.67) were the risk factors, and that vegetable intake (OR = 0.29[CI]: 0.14–0.59) and wearing a hat (OR = 0.24[CI]: 0.10–0.56) were protective factors.

Conclusions

This study has revealed the risk and protective factors of CDK, providing a new insight on related research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-02065-4.

Salzmann nodular degeneration: prevalence, impact, and management strategies

Purpose

This review will summarize the clinical and histological presentation of Salzmann nodular degeneration (SND), its prevalence and risk factors, potential underlying mechanisms, diagnostic tools, management options, and impact on cataract surgery and co-morbid ocular surface diseases.

Method

PubMed review of 44 articles published between 1976 and 2018.

Results

SND is a corneal disease characterized by whitish gray or bluish nodules on the peripheral or central cornea. The clinical presentation of SND is variable and the nodules can be asymptomatic or cause foreign body sensation and/or blurred vision. Histologically, SND appears as subepithelial nodules with thin overlying epithelium, disrupted or absent Bowman’s layer, and activated fibroblasts within the nodule. SND pathogenesis is not fully understood but is thought to involve poor epithelial protection and disruption of the epithelial–stromal interface, allowing for penetration of epithelially derived growth factors into the stroma and subsequent activation of stromal fibroblasts, eventually leading to sub-epithelial deposition of disorganized extracellular membrane components. SND most commonly occurs in Caucasian females in a bimodal distribution, occurring in the fifth or eighth and ninth decades of life. Risk factors for SND include ocular surface diseases and surgery. Surgical intervention is recommended in individuals with symptomatic nodules – primarily superficial keratectomy performed with or without intraoperative mitomycin C, photokeratectomy, and/or amniotic membrane transplantation. These procedures have been successful in removing the lesion and reducing corneal irregularity, but have variable recurrence rates (0–31%).

Conclusion

The pathogenesis of SND is complex and multifactorial. Advances in diagnostic and treatment modalities have allowed for earlier and more accurate diagnosis and effective treatment of SND.

Band-shaped keratopathy in Chinese patients with Vogt-Koyanagi-Harada syndrome

PURPOSE

To determine the incidence and characterize the clinical features of band-shaped keratopathy in Chinese patients with Vogt-Koyanagi-Harada (VKH) syndrome.

METHODS

The data of 360 consecutive VKH patients examined from November 2000 to December 2008 were reviewed. The patients were diagnosed with VKH syndrome according to international criteria. The data of VKH patients with band-shaped keratopathy, including age at disease onset, gender, intervals between disease onset and emergence of this complication, other complications, and therapy were collected and analyzed.

RESULTS

Of the 360 VKH patients, 66 patients (132 eyes) visited us at the stage of posterior uveitis or anterior uveal involvement. None of these 132 eyes had band-shaped keratopathy develop. The other 294 VKH patients (587 eyes) visited us at the stage of recurrent, granulomatous, anterior uveitis, and band-shaped keratopathy was observed in 21 eyes of 13 patients (3.6%). Of these 13 patients, there were 6 men and 7 women. Band-shaped keratopathy in 21 eyes was observed from 9 months to 32 years, with a mean of 12.7 years after the first uveitis attack. These patients had been intermittently treated with systemic corticosteroids and occasionally in combination with a transient use of either chlorambucil or azathioprine. All the eyes with band-shaped keratopathy showed recurrent and chronic intraocular inflammation. Complicated cataract, increased intraocular pressure and decreased intraocular pressure were observed in 18, 12, and 5 eyes, respectively. Ocular phthisis was observed in 1 eye. The best-corrected vision of 0.3 or less was observed in 85.1% of the affected eyes.

CONCLUSIONS

Band-shaped keratopathy is a relatively uncommon complication in VKH syndrome and mostly occurs in relatively younger patients with a long course of chronic intraocular inflammation. It was frequently associated with complicated cataract and secondary glaucoma and was a marker for poor visual outcome.