We are delighted to share a new STARSTEM publication – Nanosensitive optical coherence tomography to assess wound healing within the cornea. Team members from the TOMI, NUI Galway recently published this article in Biomedical Optics Express. The journal’s scope encompasses fundamental research, technology development, biomedical studies and clinical applications.

We asked the team to discuss their work.

What were you aiming to find out in this publication?

The aim of the study is to demonstrate the capability of nsOCT to detect structural changes deep in the cornea following superficial corneal injury and subsequent healing.

Why is this important?

Studying nanoscale structural and dynamic changes in vivo is fundamental to understanding changes occurring at cellular level before the changes manifest at the tissue level. Detecting these submicron structural changes can help scientists and clinicians to diagnose the onset of a disease, its progression and in determining treatment effectiveness of drugs.

The cornea is the transparent, avascular layer of the eye that controls the entry of light into the eye and helps to refract the light onto the retina. Corneal transparency is vital to preserve its structure and function. Corneal injuries generally arise from thermal and chemical burns. Of these, 11.5–22% of all ocular injuries occur from chemical burns, from both acids and alkali. Among chemical induced corneal burns, alkali burn causes more damage to the corneal stroma and anterior chamber compared to acid injury. Alkali ions being lipophilic, penetrate into the corneal stroma disrupting the cells and denaturing the collagen matrix, which promotes further penetration into the anterior chamber.

Hence, it is imperative to understand the nanoscale structural changes occurring during ocular injury and subsequent wound healing process in vivo for assessment of wound repair and monitoring treatment efficacy.

Describe the methods chosen.

In this paper, we have elucidated the capability of the nanosensitive OCT (nsOCT) technique to detect structural changes within the cornea to assess the impact of alkali injury and also to study the wound healing process. nsOCT offers much higher sensitivity to structural changes within the cornea compared to conventional OCT processing. The study reveals that nsOCT is able to detect structural changes with nanoscale sensitivity between healthy cornea, injured cornea and also during the reparative phase of the injury at all depths within the cornea with high statistical significance (p < 10−10).

How could this benefit citizens and patients?

The method presented offers potential for in vivo imaging applications especially in clinical imaging where sensitivity to changes in structure is of significance either to detect the onset of a disease or to evaluate the efficacy of treatment which cannot be obtained from conventional OCT processing.

It can be used for real time monitoring of corneal health following ocular trauma or ocular diseases.

What are the next steps?

Future steps will be the application of nsOCT technique to spatial and temporal structural changes within cornea following injury, treatment and healing and changes occurring due to elevated intra-ocular pressure. The technique can also be used to detect pathophysiological changes in retina following diabetic retinopathy, glaucoma and other retinal diseases.

Further applications of the technique can be used to study morphological changes in biomedical samples, for example, to image progression of cancerous cells and tumours as they are known to undergo nanoscale structural changes within their vicinity long before the manifestation of the disease.

 

Conventional OCT B-scans (a) uninjured cornea (b) after alkali induced corneal burn (c) injured cornea on 7th day (d) nsOCT B-scan of corresponding uninjured cornea (e) nsOCT B-scan following alkali induced corneal burn (f) nsOCT B-scan on 7th day following the injury. Scale bars – 500 µm.

You can find out more about the publication and download the full text over on our publications page.