Noninvasive and Noncontact Sequential Imaging of the Iridocorneal Angle and the Cornea of the Eye

Abstract

High-resolution imaging of the critical anatomic structures of the eye, especially of the anterior chamber, in vivo, remains a challenge, even with currently available state-of-the-art medical imaging techniques. This study aims for the noninvasive and noncontact sequential imaging of the iridocorneal angle, especially the trabecular meshwork (TM) and the cornea of the eye in high-resolution using a newly developed imaging platform. Methods: Bessel beam scanned light sheet fluorescence microscopy is used to attain high-resolution images of the TM. The ability of the Bessel beam to self-reconstruct around obstacles increases the image contrast at the TM region inside eye by reducing scattering and shadow artifacts. With minimal modifications, the excitation arm of the developed imaging system is adapted for noncontact, high-resolution corneal imaging. Results: High-resolution images of the TM structures and cellular-level corneal structures are obtained in ex vivo porcine eyes, and subsequently in New Zealand white rabbit, in vivo. The spatial resolution of the developed system is 2.19 μm and has a noncontact working distance of 20 mm. Conclusions: A high-resolution imaging platform for noncontact sequential imaging of the TM and the cornea of the eye is developed. This imaging system is expected to be of potential interest in the evaluation and diagnosis of glaucoma and corneal diseases. Translational Relevance: The developed prototype offers the plausibility of in vivo, noncontact, and high-resolution imaging of the iridocorneal angle and cornea of the eye that will aid clinicians in diagnosing open-angle glaucoma and corneal diseases better.

Advancements in high-resolution imaging of the iridocorneal angle

“…They only reported images in ex vivo porcine eyes and reported many user difficulties. Hong et al reported a prototype system also implementing an axicon lens to generate Bessel beam illumination in a light sheet fluorescence microscopy (LSFM) scheme (60,61). This resulted in a more accessible system with a long working-distance objective, to impart a noncontact nature to image acquisition.…”

Bessel Beams in Ophthalmology: A Review

“…nal-to-noise ratio, reduced scattering and shadowing artefacts, and higher axial res The self-reconstruction property of the Bessel beam was instrumental in increasing t trast in the scattering environment. They later reported a sequential imaging system high-resolution imaging of the ICA and the cornea of the eye and demonstrated imaging in New Zealand white rabbits [55,72]. Figure 5 shows the reported sequen aging system utilizing Bessel beam-based LSFM for TM imaging [72].…”

“…They later reported a sequential imaging system high-resolution imaging of the ICA and the cornea of the eye and demonstrated imaging in New Zealand white rabbits [55,72]. Figure 5 shows the reported sequen aging system utilizing Bessel beam-based LSFM for TM imaging [72]. Suchand Sandeep et al reported the three-dimensional (3D) visualization of the TM on an intact ex vivo porcine eye utilizing a modified version of the Bessel beam-based system [59].…”

“…In addition, it also serves the important function of transporting oxygen and nutrition to ocular tissues such as the cornea and the crystalline lens. Irregularities in the AOS can lead to an increase in intra-ocular pressure (IOP), which in turn can cause irreversible damage to the optical nerve leading to blindness [ 5 , 72 ]. This condition is known as glaucoma.…”

Non-invasive multimodal imaging of Diabetic Retinopathy: A survey on treatment methods and Nanotheranostics

“…Imaging of the retinal layers using the advanced techniques is challenging due to the non-availability of the sophisticated non-invasive system where the retinal size animal models is ten-fold smaller than that of humans. Also, there are very limited in vivo ocular non-invasive imaging methods available for retinopathy with in depth resolution [102][103][104][105][106][107]. Recently, an early detection of DR using a non-mydriatic, full field electroretinopathy, easy to operate devise was reported.…”