Effects of Superficial Keratectomy in Peripheral Hypertrophic Subepithelial Corneal Opacification on Front and Back Corneal Astigmatism

Peripheral hypertrophic subepithelial corneal opacification - Role of tear secretion, medication and systemic diseases

BACKGROUND

Peripheral hypertrophic subepithelial corneal opacification (PHSCO) is a corneal disease that may severely affect vision. The major goal of this study was to test the hypothesis that tear secretion, medication and systemic diseases are associated with PHSCO.

METHODS

This is a retrospective, case-control study conducted at the Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz. We analysed medical records of patients diagnosed with PHSCO. Sex, age, Schirmer's test II, general medication and medical history were assessed and compared to an age- and sex-matched control group from the Gutenberg Health Study (GHS).

RESULTS

One hundred ninety-five eyes of 112 patients with PHSCO were included. Eighty-eight patients were female with a mean age of 55.3 ± 14.7 years (23-89 years) and 24 patients were male with a mean age of 59.3 ± 12.6 years (38-84 years). In 83 patients (74.1%) both eyes were involved. The Schirmer's test II was significantly reduced in patients with PHSCO compared to the GHS control group (p < 0.001). Patients with PHSCO were more frequently administered artificial tears and steroid eye drops (p < 0.001) and were more hyperopic than healthy controls (p = 0.01). Systemic diseases or medication did not differ markedly between PHSCO and healthy controls.

CONCLUSION

Reduced tear secretion and more frequent use of artificial tears in patients with PHSCO suggest a link between PHSCO and dry eye disease. The results of the study do not support our hypothesis that PHSCO is associated with systemic diseases. Interestingly, patients with PHSCO were less frequently on β-blockers than control subjects.

Risk factors for peripheral hypertrophic subepithelial corneal opacification

BACKGROUND

To evaluate the phenotype, tear secretion and refractive changes of patients diagnosed with peripheral hypertrophic subepithelial corneal opacification (PHSCO).

METHODS

This is a retrospective, interventional case series conducted at the Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz. Medical records of patients diagnosed with PHSCO were analysed. Sex, age, fluorescein tear film breakup time (FTBUT), Schirmer Test II, iris colour and hair colour were assessed. Objective refraction was evaluated at different time points and, in case of surgery, 1 month and 1 year postoperatively.

RESULTS

One hundred ninety-five eyes of 112 patients (78.6% female, 21.4% male; mean age 56.2 ± 14.3) were included. The median FTBUT was 6 sec. (Q1: 4/Q3: 8.75; range 1-20 s) (measured in 70 eyes of 36 patients), the median Schirmer Test II was 8 mm (Q1: 5/ Q3:15; range 1-35 mm). In 83 patients (74.1%) both eyes were involved. In 86 eyes of 64 patients (55.3%) superficial keratectomy was performed. Sphere and cylinder changed significantly 1 month and 1 year postoperative compared to the pre-operative objective refraction, while there was no significant change between 1 month and 1 year postoperatively.

CONCLUSION

We found that PHSCO occurs mostly bilaterally in middle-aged women and appears to be associated with decreased tear production and reduced tear film stability.

The role of preterm birth, retinopathy of prematurity and perinatal factors on corneal aberrations in adulthood: Results from the Gutenberg prematurity eye study

INTRODUCTION

Prematurity and retinopathy of prematurity (ROP) are associated with altered corneal shape and reduced visual acuity in childhood, but their long-term effects on corneal shape in later life are still unclear. This study evaluated whether prematurity and related perinatal factors are associated with corneal aberrations in adulthood.

METHODS

The Gutenberg Prematurity Eye Study (GPES) is a cohort study using Scheimpflug imaging of the cornea. Associations were assessed between corneal Zernike aberrations and gestational age (GA), birth weight (BW), BW percentile, ROP occurrence, ROP treatment and other perinatal factors using univariate and multivariable linear regression analyses.

RESULTS

This study involved 444 eyes of 256 individuals born preterm (aged 28.1 ± 8.4 years, 146 females) and 231 eyes of 132 individuals born full-term (aged 29.8 ± 8.9 years, 77 females). Multivariable analyses revealed an association between corneal higher-order aberrations and lower birth weight percentile (B = -0.001, p < 0.001) as well as ROP treatment (B = 0.120, p = 0.03). Corneal lower-order aberrations were also associated with lower birth weight percentile (B = -0.004; p = 0.001) and ROP treatment (B = 0.838, p = 0.01) but not with ROP occurrence. Increased corneal aberrations were correlated with lower visual acuity and the spherical equivalent refractive error.

CONCLUSIONS

Perinatal factors, particularly low birth weight percentile and ROP treatment lead to a more irregular corneal shape in adulthood, thereby reducing optical image quality and potentially contributing to reduced visual acuity and altered refractive error.

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.