The Inflammation Level and a Microbiological Analysis of the Anophthalmic Cavities of Unilateral Ocular Prosthesis Users: A Blind, Randomized Observational Study

Tear secretion is preserved while the area of meibomian glands is reduced in patients with prosthetic eyes, contributing to the symptoms of dry eye

BACKGROUND/AIMS

It is unclear whether a reduction in tear secretion contributes to the discomfort experienced by those with prosthetic eyes. Tear secretion has hitherto only been measured with the Schirmer test which may be affected by the pooling of tears behind the prosthesis. In this study, direct imaging of the lacrimal gland has been performed to measure tear secretion in anophthalmic sockets. The relation between the area of meibomian glands and dry eye symptoms was also assessed.

METHODS

12 patients were included. The amount of tear secretion was measured by direct imaging of the lacrimal gland while the presence of meibomian glands was determined using meibography. The 5-item Dry Eye Questionnaire was used to assess symptoms of dry eye.

RESULTS

No difference was found in tear secretion between the anophthalmic socket and the contralateral eye. The area of meibomian glands was significantly reduced in eyelids on the side of the prosthetic eye, compared with the contralateral eye. Seven patients reported symptoms indicative of dry eye in the anophthalmic socket, compared with only two in the contralateral eye.

CONCLUSIONS

The effects of an eye prosthesis on meibomian glands may contribute to the frequently perceived symptoms of dry eye despite unaffected in tear secretion.

Microbiological evaluation of conjunctival anopthalmic flora after using digital 3D-printed ocular prosthesis compared to conventional one: a randomized clinical trial

BACKGROUND

This study aims to assess the influence of using 3D-printed acrylic resin versus conventional Poly-methyl methacrylate (PMMA) for fabricating ocular prostheses on the biofilm and microbial flora of anophthalmic socket.

METHODS

A randomized controlled trial was designed as a parallel group study. Participants were allocated randomly into two groups: the control group, which received conventionally fabricated ocular prostheses (CG, n = 11), and the test group, which received digitally 3D-printed ocular prostheses (DG, n = 11). Microbiological analysis was conducted before prosthesis insertion and three months after using the ocular prosthesis. Swab samples were inoculated on blood agar, MacConkey's agar, and Sabouraud's dextrose agar (SDA) for isolating Gram-positive, Gram-negative, and fungal organisms, respectively. Subsequently, the plates were incubated at 37 degrees Celsius for 48 h. Additionally, a validated questionnaire was used for subjective clinical evaluation, including parameters such as comfort level, socket discharge, lacrimation, and frequency of lubrication for each ocular prosthesis patient in both groups.

RESULTS

Test group (DG, n = 11) exhibited a positive, though statistically insignificant, difference (p > 0.001) in microbial growth when compared to the control group (CG, n = 11). A statistically significant difference was observed in comfort levels between the two groups, with more comfort level within group II (test group) patients. While parameters such as discharge amount, discharge location, lacrimation and lubrication frequency displayed statistically insignificant differences between the two groups, all parameters showed improved results after three months of prosthesis use.

CONCLUSIONS

The choice of ocular prosthesis fabrication technique did not yield a statistically significant difference in anophthalmic flora. However, the 3D-printed acrylic resin, as an artificial eye material, displayed potential advantages in reducing the colonization of opportunistic pathogens. All subjective clinical evaluation parameters exhibited enhanced outcomes after three months of prosthesis use, emphasizing the need for an adaptation period during which patients complains are alleviated. In comparison with PMMA, 3D-printed acrylic resin showcased a certain degree of anti-colonization ability against pathogenic bacteria, along with a significant level of patient comfort, suggesting its potential as a promising material for ocular prostheses.

TRIAL REGISTRATION

This parallel double-blinded RCT has been registered at ClinicalTrials.gov with identification number: NCT05584865, 18/10/2022.

Analysis of microbial communities of ocular prostheses and anophthalmic sockets using 16S rRNA gene sequencing

Ocular prostheses are liable to host microbial adhesion, which can favor conjunctival inflammation. Knowing the microbiota of the ocular prosthesis and anophthalmic socket is important for predicting infection-related pathogens. This study evaluated the microbiota of the prostheses and anophthalmic sockets of six individuals by 16S rRNA sequencing. The microbial abundance and diversity were analyzed using the Operational Taxonomic Units at the genus level. Forty-seven phyla, capturing 1,258 named genera, were recorded in the sample set. In both sites, the most frequent genera were Fusobacterium, Staphylococcus, Prevotella, and Streptococcus. The microbial abundance was higher for the anophthalmic socket than for the prosthesis. Alpha diversity showed no significant differences in bacterial richness or diversity between sites. Although the microbial abundance in the anophthalmic socket was higher, both sites had similar microbiota with high diversity and low dominance among the genera.