Risa Yamazaki-Hokama

Background: Anemia is a common systemic condition associated with adverse maternal, perioperative, and cardiovascular outcomes. Although timely screening is clinically important, diagnosis still relies on invasive blood testing. Palpebral conjunctival pallor has traditionally been used as a noninvasive indicator of anemia, but its diagnostic accuracy remains limited. This study aimed to develop and validate a deep learning system to estimate hemoglobin (Hb) concentration and screen for anemia using palpebral conjunctiva images captured with a smartphone-compatible slit-lamp microscope. Methods: In this prospective observational study, 225 Japanese participants (20–92 years) underwent conjunctival imaging and blood testing. Palpebral conjunctiva videos were obtained using the Smart Eye Camera. Video frames were processed using automated anterior-segment segmentation and conjunctiva extraction. A ConvNeXt-based regression model was trained to predict Hb values. Anemia was defined using sex-specific Hb thresholds. Results: From 225 videos, 53,776 frames were extracted, yielding 9903 quality-filtered conjunctiva images (training: 8082; test: 1821). Video-level predicted Hb values moderately correlated with measured Hb (r = 0.42). For anemia screening, frame-level analysis achieved an AUC of 0.75, with accuracy of 0.76, sensitivity of 0.71, and specificity of 0.79. Video-level aggregation achieved 69% accuracy. Conclusions: Deep learning analysis of palpebral conjunctiva images acquired with a portable slit-lamp microscope demonstrated the feasibility of non-invasive hemoglobin estimation and anemia screening. Although the proposed approach achieved moderate performance, further improvements in model accuracy and prospective multi-center validation are required before clinical implementation.

Biological extracellular vesicles in tear fluids, such as exosomes, are thought to have physiological functions in the management of healthy ocular surface epithelium, including corneal epithelium. However, the physiological roles of tear extracellular vesicles in the ocular surface remain unclear. In this study, we investigated the physiological function of tear extracellular vesicles in mouse tear fluids in the ocular surface epithelium in vitro. Morphological analysis of the isolated extracellular vesicles from mouse tear fluids was performed using nanoparticle tracking analysis and transmission electron microscopy. The identified particles were characterised by immunoblotting for exosomal markers. After confirming the uptake of tear exosomes in cultured corneal epithelial cells, gene expression changes in mouse cultured corneal epithelial cells after tear exosome treatment were analysed. Immunostaining analysis was performed to confirm cell proliferation in the cultured corneal epithelial cells with tear exosome treatment. Tear fluids from mice contain nanoparticles with exosome-like morphologies, which express the representative exosomal markers CD9 and TSG101. The extracellular vesicles can be taken up by cultivated murine corneal epithelial cells in vitro and induce expression changes in genes related to the cell cycle, cell membranes, microtubules, and signal peptides. Treatment with the tear extracellular vesicles promoted cell proliferation of cultured murine corneal epithelial cells. Our study provides evidence that murine tear fluids contain extracellular vehicles like exosomes and they may contribute to the maintenance of the physiological homeostatic environment of the ocular surface.

Rationale: Patients with atopic dermatitis undergoing penetrating keratoplasty (PKP) face a high risk of postoperative complications. Endothelial keratoplasty may be a safer alternative for such patients, including those with abnormal anterior chamber anatomy. Patient concerns: 3 male patients, aged 33 to 44, presented with blurred vision at Keio University Hospital. Diagnosis: Bullous keratopathy was diagnosed through slit-lamp examination and specular microscopy. Two patients had well-controlled systemic atopic dermatitis, while 1 had blepharitis associated with atopic dermatitis. Two patients had peripheral anterior synechia, and 2 had undergone glaucoma surgery before keratoplasty. Interventions: Non-Descemet stripping endothelial keratoplasty (nDSAEK) was performed by a single surgeon. Outcomes: The best-corrected visual acuity ranged from 0.7 to 1.5 logMAR before surgery and from 0.2 to 2.3 logMAR after surgery. One year post-surgery, the graft remained clear in 2 cases; however, in the case of repeated glaucoma surgeries after nDSAEK, the graft became edematous. Corneal endothelial cell density was 1586 and 1988 cells/mm² in 2 cases and undetectable in the failed case. The follow-up period ranged from 2.5 to 9 years. Lessons: Despite the presence of peripheral anterior synechia or prior glaucoma surgery, some patients experienced a favorable long-term postoperative course following nDSAEK. This procedure may offer a safer alternative for treating patients with atopic dermatitis who have ocular complications that present a high risk for PKP.