The association of demodex infestation with pediatric chalazia.

PURPOSE: This study aimed to investigate the association of Demodex infestation with pediatric chalazia. METHODS: In a prospective study, 446 children with chalazia and 50 children with non-inflammatory eye disease (controls) who underwent surgical treatment were enrolled from December 2018 to December 2019. Patient ages ranged from 7 months to 13 years old. All patients underwent eyelash sampling for light microscope examination, and statistical correlation analysis between Demodex infestation and chalazia, including the occurrence, recurrence, and course of disease, morphological characteristics, and meibomian gland dysfunction (MGD) in chalazia patients was performed. RESULTS: Demodex was found in 236 (52.91%) patients with chalazia and zero control patients. Demodicosis was significantly more prevalent in chalazia patients than the control group (P < 1 × 10- 14). Recurrent chalazia (P = 0.006) and skin surface involvement (P = 0.029) were highly correlated with Demodex infestation. Demodicosis was also associated with multiple chalazia (P = .023) and MGD(P = .024). However, Demodex infestation was comparable in the course of disease (P = 0.15), seasonal change (P = 0.68) and blepharitis subgroups (P = 0.15). Within the group of chalazia patients who underwent surgical removal of cysts, 4 (0.9%) patients with concurrent demodicosis experienced recurrence. CONCLUSIONS: Demodex infestation was more prevalent in pediatric chalazia patients than healthy children, and was associated with recurrent and multiple chalazia. Demodicosis should be considered as a risk factor of chalazia. In children with chalazia, Demodex examination and comprehensive treatment of Demodex mites should be applied to potentially prevent recurrence.

[Effects of pericytes on the leakage of rat corneal neovascularization].

OBJECTIVE: To explore the effects of pericytes on the leakage of rat corneal neovascularization (CNV). METHODS: CNV was induced by micropocket assay in rats. Two eyes of the same rat were divided randomly into experimental and control groups. The experimental group received the VEGF + anti-PDGF-B pellet while the control group the VEGF + PBS pellet. Corneal samples were excised at Day 5 postoperation. CNV leakage was measured by Evans blue method. Pericyte coverage index (MPI) was applied to quantify the pericyte coverage through double immunofluorescent stain of frozen sections of corneas with CD31 as endothelial and α-smooth muscle actin (α-SMA) as pericyte marker. Corneal weight was measured. RESULTS: In the control group, MPI was 56.5%, cornea weight (7.36 ± 0.56) mg and CNV permeability rate (0.24 ± 0.07) µg×ml(-1)×mm(-2). In the experimental group, MPI was 11.3%, cornea weight (8.96 ± 1.09) mg and CNV permeability rate (0.68 ± 0.36) µg×ml(-1)×mm(-2). The intergroup difference was statistically significant (P MPI<0.01, P permeability= 0.01, P weight = 0.01). CONCLUSION: Pericytes inhibit the leakage of rat CNV. Such findings may guide the clinical management of hyperpermeability.

[A preliminary study on intravitreal injection of bevacizumab for treatment of neovascular age-related macular degeneration].

OBJECTIVE: To evaluate the short-term safety of intravitreous bevacizumab (Avastin) and its effects on visual acuity (VA) and subfoveal choroidal neovascularization (CNV) in patients with neovascular age-related macular degeneration (ARMD). METHODS: Single-center, uncontrolled clinical study. Five ARMD patients (5 eyes) with subfoveal CNV and best-corrected VA (BCVA) less than 0.1 were participated. Patients were treated with an intravitreous injection of bevacizumab (1.5 mg, 0.06 ml). Ophthalmologic evaluations included BCVA test, ocular examination, intraocular pressure (IOP) measurement, optical coherence tomography (OCT) imaging and fluorescein angiography (FFA). RESULTS: There were no ocular or systemic adverse events observed, except a mild elevation of IOP [26 mm Hg (1 mm Hg = 0.133 kPa)] in 1 case on the 3rd day after injection, which was controlled by topical medication. One out of 5 eyes had a significant improvement of BCVA (from 0.1 improved to 0.4) in one week after injection. By 2 months, the BCVA increased in 4 cases (increased 1 to 6 lines) and 3 of them remained stable for 4 to 6 months and 1 decreased at the 4 th month post injection. The thickness of central retina reduced 5.9% to 41.4% and FFA revealed a remarkable reduction or an absence of leakage from CNV in 3 eyes by the 4th month. CONCLUSION: Our preliminary results are promising, showing that intravitreous bevacizumab therapy is well tolerated with an improvement in VA, OCT, and FFA outcomes. A multi-center randomized controlled clinical trial is needed to evaluate the long-term safety and effectiveness of intravitreous bevacizumab therapy on neovascular ARMD.