Investigating Microinvasive Intra-Ocular Biopsy

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Surgical Innovation

Background:

• Current intraocular biopsy methods using small gauge needles and subretinal cannulae risk wound leakage.
• Investigating microneedles with internal diameters as small as 49G for improved intraocular biopsy.
• Focus on both posterior and anterior segments of the eye.

Purpose of the Study:

• To evaluate the feasibility of using microneedles for intraocular biopsy.
• To assess cell viability after aspiration with microneedles.
• To determine the wound sealing properties of microneedle punctures in ocular tissues.

Main Methods:

• Aspiration of human uveal melanoma and retinoblastoma cell lines using various microneedle sizes.
• In vitro analysis of cell viability post-aspiration.
• Ex vivo porcine eye model for simulating retinal puncture and anterior chamber puncture with microneedles.
• Optical coherence tomography (OCT) and histology for imaging and analysis.

Main Results:

• Microneedles successfully aspirated ocular cancer cells (retinoblastoma, uveal melanoma) with high cell viability (72.83% for 49G).
• A 49G microneedle created a self-sealing retinal wound in ex vivo porcine eyes, preventing reflux of 200nm microbeads.
• Anterior chamber puncture with microneedles resulted in 0% aqueous leakage, significantly outperforming larger gauge needles.

Conclusions:

• A microinvasive approach using microneedles for intraocular biopsy is feasible.
• Microneedles offer a promising alternative to current methods, minimizing leakage.
• Further in vivo studies are warranted to validate these findings.