Prevalence of Ocular Demodicosis and Ocular Surface Conditions in Patients Selected for Cataract Surgery

Abstract

The aim of the study was to analyze the prevalence of ocular demodicosis and ocular surface conditions in patients selected for cataract surgery. Eyelashes from 73 patients selected for cataract surgery were evaluated at × 40 and × 100 magnification using light microscopy. The anterior segment was assessed with the slit lamp. Additionally, Schirmer I and break up time (BUT) tests were carried out before surgery and 1 and 3 months postoperatively. A specially designed questionnaire containing e.g. information about chronic skin and eye diseases, previous ophthalmic surgeries, and patient's hygiene habits was used to assess the demographic variables. A majority of patients were at the age of 70–79 years, and there were more females (83%) in the study group. Demodex folliculorum was found in 48% of the patients. There was a correlation between the number of parasites and the presence of blepharitis, discharge at eyelid margins, and conjunctival hyperemia. Schirmer I and BUT test results were lower in patients with Demodex infestation before and after cataract surgery. The higher number of mites was correlated with lower Schirmer I test results postoperatively. The presence of Demodex mites influences the conjunctiva and lid margins leading to inflammation. The higher number of Demodex mites disturbs the tear film over time after cataract surgery.

Age differences in ocular demodicosis: Demodex profiles and clinical manifestations

“…Our results showed that there was no significant difference in Demodex counts between young and elderly patients, which was inconsistent with previous studies showing that demodicosis is highly age-dependent (8,13,26). We further discovered that the D. brevis counts and D. brevis % of the young group were higher than that of the elderly group.…”

“…In the present study, it can be clearly seen that the young group had a higher prevalence of corneal changes involving the stroma, such as infiltration or ulceration, while SPK was the main corneal change in elderly people. Our previous research and the findings in this study provide strong support to D. brevis or D. brevis % as a risk factor for corneal changes in young patients with ocular demodicosis (13)(14)(15). This study revealed that there are relatively fewer D. brevis mites and milder corneal changes in elderly patients, which further supports our notions that D. brevis plays a more important role in the pathogenesis of ocular demodicosis.…”

“…Ocular demodicosis has been implicated in ocular surface inflammation, including blepharitis, eyelash disorders, meibomian gland dysfunction (MGD), chalazia, and blepharoconjunctivitis (BKC) (5)(6)(7)(8)(9)(10). The incidence of Demodex infestation increases with age: it is observed in 84% of the general population aged over 60 years and Original Article 100% of the general population over 70 years old but is reported to be very rare in healthy children under 16 years of age (11)(12)(13). However, we previously reported ocular Demodex infestation in 12 paediatric patients who were diagnosed with BKC but failed to respond to conventional treatments (8).…”

“…Among these symptoms, itching and eye dryness were the two most common in both groups. Young patients had more blurred vision (40.7% vs. 9.8%, P<0.001), more redness (36.3% vs. 21.7%, P=0.030), and more eye pain (24.2% vs. 2.2%, P<0.001), while older patients had more eye fatigue (67.4% vs 13…”

Cataract Surgery by Intraoperative Surface Irrigation with 0.25% Povidone–Iodine

“…It is also known that the incidence and severity of dry eye symptoms may increase after cataract surgery. To achieve the best outcome in cataract surgery, a healthy ocular surface is crucial [83]. In patients who have already developed corneal epithelial cell damage caused by diabetes or dry eye, ocular surface irrigation with 0.25% povidone-iodine may transiently exacerbate the corneal damage.…”