A hybrid method for 3D mosaicing of OCT images of macula and Optic Nerve Head

The role of ultra-widefield imaging with navigated central and peripheral cross-sectional and three-dimensional swept source optical coherence tomography in ophthalmology: Clinical applications

PURPOSE

To assess central and peripheral retinal and choroidal diseases using ultra-widefield (UWF) fundus imaging in combination with navigated central and peripheral cross-sectional and three-dimensional (3D) swept source optical coherence tomography (SS-OCT) scans.

METHODS

Retrospective study involving 332 consecutive patients, with a nearly equal distribution of males and females. The mean age of patients was 52 years (range 18-92 years). Average refractive error was -3.80 D (range +7.75 to -20.75 D).

RESULTS

The observations in this study demonstrate the efficacy of peripheral navigated SS-OCT in assessing various ocular conditions. The technology provides high-quality images of the peripheral vitreous, vitreoretinal interface, retina, and choroid, enabling visualization of vitreous floaters and opacities, retinal holes and tears, pigmented lesions, and peripheral retinal degenerations. 3D OCT scans enhance the visualization of these abnormalities and improve diagnostic and therapeutic decisions.

CONCLUSION

Navigated central and peripheral cross-sectional and 3D SS-OCT scans offer significant complementary benefits in the assessment and management of retinal diseases. Their addition to UWF imaging provides a comprehensive view of central and peripheral ocular structures, aiding in early detection, precise anatomical measurements, and objective monitoring of disease progression. In addition, this technology serves as a valuable tool for patient education, a teaching tool for trainees, and documentation for medico-legal purposes.

Comparison of exosomes derived from induced pluripotent stem cells and mesenchymal stem cells as therapeutic nanoparticles for treatment of corneal epithelial defects

Induced pluripotent stem cells and mesenchymal stem cells are pluripotent stem cells that represent promising therapies for treating various tissue injuries and wound healing. Exosomes are nanosized extracellular vesicles that have been identified as important mediators of therapeutic functions, which are performed via cell communication. In this study, we compared the efficacy of induced pluripotent stem cells-derived exosomes (iPSCs-Exos) and mesenchymal stem cells-derived exosomes (MSCs-Exos) in treating corneal epithelial defects. The characteristics of the two types of exosomes were not significantly different. Compared to MSCs-Exos, iPSCs-Exos had a better in vitro effect on the proliferation, migration, cell cycle promotion and apoptosis inhibition of human corneal epithelial cells. iPSCs/MSCs-Exos promoted cell regeneration by upregulating cyclin A and CDK2 to drive HCECs to enter the S phase from the G0/G1 phase. In vivo results from a corneal epithelial defect model showed that both iPSCs-Exos and MSCs-Exos accelerated corneal epithelium defect healing while the effects of iPSCs-Exos were much stronger than those of MSCs-Exos. This study demonstrated that iPSCs-Exos had a better therapeutic effect on corneal epithelial defect healing. Thus, a novel potential nanotherapeutic strategy for treating corneal epithelial defects and even more ocular surface disease could be undertaken by using iPSCs-Exos dissolved in eye drops.

Three-dimensional surface presentation of optic nerve head from SPECTRALIS OCT images: observing glaucoma patients

PURPOSE

To propose an innovative three-dimensional surface presentation of the optic nerve head (ONH) from the SPECTRALIS optical coherence tomography (OCT) device.

METHOD

A dataset of OCT ONH files from eight glaucoma follow-up patients was obtained. The set consisted of OCT ONH images for 20 right eyes (OD) and 17 left eyes (OS). Preprocessing steps followed with OCT reconstruction procedures were designed. The three-dimensional (3D) surface rendering was generated for all OCT ONH images. A set of eight International Organization for Standardization (ISO) roughness parameters were calculated to assess the disparities in the 3D ONH surface morphology during follow-up visit.

RESULTS

The 3D ONH surface presents a new OCT display to ophthalmology; so, the physician can examine the surface morphology of the OCT ONH region. The 3D ONH surface's shape varied noticeably during follow-up visits in glaucoma patients. The percentage disparity of ONH surface roughness's can be as small as 3% or almost zero, but it can be as large as 56% or 100%.

CONCLUSIONS

The approximation of OCT ONH 3D surface is feasible; it may possibly be beneficial to ophthalmology. It allows ophthalmologist to perceive the entire changes in the ONH surface morphology during the follow-up attendances; so, it can be used to observe patient health. The ISO roughness measurements are suggestive complementary factors to observe the alterations in the OCT ONH region.