Feline ocular diseases can cause irreversible vision loss if they are not detected early. However, early diagnosis is often difficult. This is due to limited access to veterinary ophthalmology services and the challenge of distinguishing between visually similar eye conditions. Illumination changes, glare, and strong visual similarity among diseases substantially limit the performance of conventional RGB-based classification models. This paper proposes the Color Space Fusion Network (CSF-Net), an attention-guided color interaction framework for robust feline ocular disease classification in real-world environments.

Blepharitis is a chronic inflammation of the eyelid margin that is mediated by the immune system. It is one of the common ocular surface diseases and often leads to serious sequelae that threaten vision, such as dry eye syndrome due to insufficient tear secretion, corneal neovascularization, and stubborn chalazion. Elucidating its precise etiology is therefore imperative. Emerging high-throughput sequencing and metagenomic analyses have unveiled a quantitative and qualitative disruption of the periocular microbiome (dysbiosis), characterized by the expansion of specific bacterial species such as Staphylococcus aureus, coupled with episodic blooms of Demodex. These perturbations are no longer considered epiphenomena. In this review, we reveal the possible mechanisms of the role of blepharitis and microbiota dysbiosis.

Demodex blepharitis is a chronic inflammatory ocular condition caused by Demodex mite infestation of the eyelid that can negatively impact quality of life. Currently, lotilaner ophthalmic solution 0.25% is the only FDA-approved treatment for Demodex blepharitis. The Demodex Expert Panel on Treatment and Eyelid Health has established consensus that lotilaner ophthalmic solution 0.25% should be considered the preferred first-line treatment for Demodex blepharitis. We report a patient who presented with collarettes, the pathognomonic sign of Demodex blepharitis, meibomian gland dysfunction, and poor visual acuity. The patient also had a history of neovascular age-related macular degeneration. Consistent with the Demodex Expert Panel on Treatment and Eyelid Health consensus recommendations, the patient was treated with lotilaner ophthalmic solution 0.25%, lid scrubs, and warm compresses. At the 2-month follow-up, collarettes had resolved, and signs of meibomian gland dysfunction had improved. This case supports the Demodex Expert Panel on Treatment and Eyelid Health recommendation that lotilaner ophthalmic solution 0.25% should be considered the preferred first-line treatment for Demodex blepharitis.

A 19-year-old male undergoing systemic isotretinoin therapy presented with bilateral corneal nodules resembling Salzmann nodular degeneration (SND). He had no prior ocular comorbidities and reported mild itching. Slitlamp examination revealed inflammatory nodules with pannus and blepharitis; optical coherence tomography (OCT) confirmed no stromal involvement. Systemic retinoid therapy was discontinued, and topical antiinflammatory treatment initiated. Despite transient visual decline, the patient improved over six months, with resolution of symptoms and stabilization of the corneal lesions. The temporal relationship between isotretinoin use and lesion onset, in the absence of other risk factors, suggests a possible association between systemic retinoids and SND-like pathology. This case highlights the importance of ophthalmologic monitoring in patients on retinoid therapy and raises awareness of potential corneal complications.

Conjunctivitis, keratitis, endophthalmitis, and blepharitis are among the most prevalent bacterial eye infections. Topical eye drops are convenient but often exhibit low ocular bioavailability due to anatomical and physiological barriers, which may contribute to subtherapeutic exposure and antimicrobial resistance. Besifloxacin (BFX), a fourth-generation fluoroquinolone approved exclusively for ophthalmic use, has poor aqueous solubility at tear pH and is currently marketed as a suspension requiring frequent instillation. This study aimed to develop and optimize besifloxacin-loaded nanostructured lipid carriers (BFX-NLCs) to improve delivery. BFX-NLCs were prepared by high-pressure homogenization and optimized using response surface methodology, with particle size (Z-average) as the primary response. The optimized formulation exhibited a mean particle size of ~100 nm, a polydispersity index <0.25, and an entrapment efficiency of ~75%. In vitro release in simulated tear fluid showed a sustained release profile, reaching ~65% BFX release at 24 h, best described by the Korsmeyer-Peppas model (diffusion exponent n = 0.86), indicating anomalous (non-Fickian) diffusion. The minimum inhibitory concentrations of BFX-NLC against Staphylococcus aureus ATCC 23235 and Pseudomonas aeruginosa ATCC 9027 were comparable to those of free BFX, demonstrating preservation of antimicrobial activity. BFX-NLCs were non-toxic in the Galleria mellonella larvae model and exhibited suitable viscosity and osmolality for ophthalmic use, as well as physical stability and entrapment efficiency over nine months of storage. These findings support BFX-NLCs as a promising lipid-based platform for topical ocular delivery of besifloxacin, with potential to enhance therapeutic efficacy and reduce dosing frequency in bacterial eye infections.

This report describes the case of a four-year-old girl with idiopathic facial aseptic granuloma (IFAG) who developed persistent, treatment-resistant eyelid and facial inflammation despite multiple courses of antibiotics and corticosteroids. Her presentation included recurrent hordeola, severe blepharitis, and a cheek nodule, with a clinical picture more consistent with IFAG than pilomatrixoma despite histologic evidence of the latter. Standard therapies provided only transient benefit and were limited by systemic side effects. Initiation of topical tacrolimus 0.03% ointment led to rapid and sustained improvement in redness, irritation, and nodularity. This case highlights topical tacrolimus as a promising non-steroidal option for children with prolonged or refractory IFAG.

Background/Objectives: The ocular surface is continuously exposed to microorganisms, and disruption of host-microbial balance may lead to infection or postoperative complications. Increasing antimicrobial resistance and biofilm formation have highlighted the need for alternative or complementary non-antibiotic strategies to control ocular surface microbial burden. Liposomal ozonated oil eyedrops have demonstrated antimicrobial and antibiofilm activity in preclinical and preliminary clinical studies. The aim of this study was to evaluate changes in ocular surface microbiological culture results before and after treatment with liposomal ozonated oil eyedrops in a real-world clinical setting. Methods: This was a prospective, observational, real-world pre-post study including 101 eyes from 101 patients undergoing ocular surface microbiological sampling in routine clinical practice. Two samples were obtained per patient: Sample I immediately before treatment and Sample II at the routine follow-up visit after short-course treatment with liposomal ozonated oil eyedrops (1 drop, four times daily, for 4 days). The interval between samples ranged from 3 to 5 days (median 3 days). Microbiological cultures were classified as positive or showing no growth. Paired changes in culture positivity were analyzed using McNemar's exact test. Results: At baseline, 87 of 101 samples (86.1%) yielded positive cultures, while 14 (13.9%) showed no growth. Following treatment, culture positivity decreased to 11 of 101 samples (10.9%), with 90 samples (89.1%) showing no growth. Among baseline-positive samples, microbiological clearance was observed in 76 cases (87.4%). No cases converted from culture-negative to culture-positive at follow-up. The reduction in culture positivity after treatment was statistically significant (McNemar's exact test, p < 0.001). Recent antibiotic exposure within 14 days prior to baseline sampling was reported in 8 patients (7.9%). Persistent positive cultures were observed in a minority of cases and were mainly associated with common ocular surface pathogens. Conclusions: In routine clinical practice, short-term treatment with liposomal ozonated oil eyedrops was associated with a significant reduction in ocular surface culture positivity over a short follow-up interval.

Phlyctenular keratoconjunctivitis (PKC) goes beyond limbal nodules. This pediatric ocular surface condition caused by delayed-type hypersensitivity to microbial antigens. The trigger is context-dependent: Mycobacterial antigens in tuberculosis-endemic areas; staphylococcal eyelid disease and rosacea in high-income areas. Although classically bacterial-driven, virus-associated presentations like herpes simplex virus (HSV)-linked phlyctenular disease, pediatric PKC during acute coronavirus disease 2019 (COVID-19) infection, and molluscum contagiosum-driven keratoconjunctivitis suggest the same antigen-mediated pathway. Photophobia and discomfort are prevalent, and corneal involvement can cause neovascularization, scarring, amblyopia, and perforation. This minireview combines epidemiologic, clinical, and immunopathologic data to identify causes and update care. Practical takeaways: (1) Treat the antigen source (blepharitis/rosacea, chlamydia, parasites) and screen for tuberculosis when risk factors exist. Consider viral triggers when history or exam suggest HSV, recent COVID-19, or eyelid molluscum; (2) Suppress inflammation promptly with a short, carefully tapered course of topical corticosteroids; (3) Use topical cyclosporine as a steroid-sparing agent in recurrent or steroid-dependent disease; and (4) Reduce antigen load with lid hygiene and targeted antimicrobials. Start antitubercular treatment for tuberculosis. If a viral cause is anticipated, add antiviral medication or molluscum lesion eradication to the steroid-sparing regimen. Trigger-focused, steroid-sparing treatment reduces recurrences, vision-threatening consequences, and steroid exposure.

Herpes zoster ophthalmicus results from the reactivation of latent varicella zoster virus involving the ophthalmic branch of the trigeminal nerve and may lead to severe ocular complications. Hutchinson's sign, defined by vesicular or crusted lesions on the nasal tip, is a key predictor of ocular involvement.  We describe a 57-year-old woman with no relevant past medical history who presented with a 15-day history of pruritus and burning in the right eye. She was initially misdiagnosed with blepharitis and later periorbital cellulitis, receiving topical tobramycin and systemic antibiotics without improvement. On further evaluation, necrotic crusted lesions on the nasal tip and right frontal region were observed. The integration of clinical features, including dermatomal involvement, nasal tip lesions, and necrosis, established the diagnosis of herpes zoster with associated bacterial superinfection. Oral valaciclovir and clindamycin were initiated, resulting in a favorable clinical response with the progressive resolution of lesions and no ocular complications, underscoring the benefit of combined antiviral and timely antibiotic therapy. This case highlights the importance of early recognition of Hutchinson's sign and timely initiation of antiviral therapy to prevent visual sequelae while also emphasizing the need to identify and adequately manage bacterial superinfection in herpes zoster lesions, including the prompt initiation of appropriate antibiotic therapy when indicated.