Objective To evaluate the clinical features of acute macular neuroretinopathy (AMN) associated with COVID-19. MethodsA retrospective case series studies. A total of 12 eyes of 8 patients diagnosed of AMN associated with COVID-19 at Peking University People’s Hospital from December 5, 2022 to January 5, 2023 were included. Of the 8 patients, 2 were male (4 eyes) and 6 were female (8 eyes), with an average age of (29.38±8.60) years. All patients underwent best-corrected visual acuity (BCVA), spectral-domain optical coherence tomography (OCT), and infra-red fundus photography (IR). After definite diagnosis, the patients were given symptomatic treatment such as local vasodilation, anti-inflammatory and systemic circulation improvement and nutritional nerve. Follow-up time was 21-30 days weeks. Clinical manifestations, OCT and IR image characteristics, and treatment outcomes were retrospectively analyzed. ResultsThe time from diagnosis of COVID-19 to the onset of ocular symptoms was (3.00±0.93) days. Among 12 eyes, 6 had complaints of paracentral scotoma, with 2 of them accompanied by visual acuity loss; and 6 had complaints of dark shadows in the vision, with 2 of them accompanied by visual acuity loss. At the initial examination, 2 eyes had a BCVA of less than 0.05, 2 eyes had a BCVA between 0.4 and 0.6, and 8 eyes had a BCVA between 0.8 and 1.0. At the last follow-up, visual symptoms improved in 7 eyes and remained unchanged in 5 eyes. Fundus color photography showed reddish-brown lesions in the macular area. Spectral-domain OCT revealed localized thickening and strong reflection of the outer plexiform layer (OPL) in the macular area, patchy strong reflections in the outer nuclear layer (ONL), and varying degrees of local discontinuity in the adjacent external limiting membrane, ellipsoid zone/interdigitation zone (EZ/IZ), with reduced local reflection in the adjacent retinal pigment epithelium layer in 2 eyes. The strong reflection area of the ONL on corresponding structural OCT was observed more clearly as a lesion range with strong reflection on en-face OCT. The incomplete structure of the EZ/IZ band was observed more clearly as a lesion range with weak reflection on en-face OCT. IR showed several clear-bordered and weakly reflecting lesions at the center of the macula, with the tip pointing to the fovea. ConclusionsAMN associated with COVID-19 tends to occur in young females. The OCT findings of AMN are characterized by strong reflections in the OPL and ONL, and lesion ranges can be observed more clearly at different levels using en-face OCT. The lesions on IR appear as weak reflections.
ObjectiveTo explore the differences in metabolomic changes and metabolic pathways between the vitreous humor and serum of patients with early-onset proliferative diabetic retinopathy (PDR). MethodsA prospective observational study. From January to June 2025, 30 patients with PDR who underwent pars plana vitrectomy (PPV) in the Department of Ophthalmology, Peking University People's Hospital were included in the study. Patients were categorized into an early-onset PDR group (diagnosis age ≤40 years, n=10) and a late-onset PDR group (diagnosis age ＞40 years, n=20) based on the age at diabetes diagnosis. Fasting serum samples collected preoperatively and vitreous humor samples obtained intraoperatively were analyzed using untargeted metabolomics via ultra-high-performance liquid chromatography coupled with electrostatic field orbitrap tandem mass spectrometry. Differential metabolites were screened with thresholds of P＜0.05, variable importance in projection＞1, and fold change＞1.200 or ＜0.833. Pathway enrichment analysis was performed using the Kyoto Encyclopedia of Genes and Genomes (KEGG). The Mann-Whitney U test was used to compare clinical data between the two groups. ResultsSignificant differences were observed between the early-onset and late-onset PDR groups in the age at diabetes diagnosis and diabetes duration (Z=?4.41, ?2.62; P＜0.05). Metabolomic analysis identified 37 differential metabolites in the vitreous humor (34 upregulated, 3 downregulated) and 42 in the serum (10 upregulated, 32 downregulated). The two most abundant classes of differential metabolites common to both sample types were carboxylic acids and derivatives (16.2% in vitreous, 16.7% in serum) and fatty acyls (13.5% in vitreous, 11.9% in serum). KEGG enrichment analysis revealed the tryptophan metabolism pathway was significantly enriched in the vitreous humor (enrichment factor=0.024, P＜0.05), with L-kynurenine and indole-3-acetamide as key differential metabolites. In the serum, the taurine and hypotaurine metabolism pathway was significantly enriched (enrichment factor=0.042, P＜0.05), with hydroxyethanesulfonic acid identified as a differential metabolite. ConclusionsEarly-onset PDR has characteristic metabolic disorders. The dual activation of the kynurenine and indole branches of tryptophan metabolism in the vitreous humor, alongside increased consumption in the taurine pathway in serum, may underlie its pathophysiology. Additionally, abnormalities in serum steroids and steroid derivatives suggest that dysregulated steroid hormone metabolism might contribute to disease progression.