Dissertation Defense: Kenneth Marcelino, "Development of a Portable In Vivo Confocal Ophthalmoscope (PICO) for Non-Contact Corneal Imaging"

When

April 8, 2026, 10 a.m. – 1 p.m.

Where

Meinel 821

Title

Development of a Portable In Vivo Confocal Ophthalmoscope (PICO) for Non-Contact Corneal Imaging

Abstract

Microbial keratitis is a leading cause of visual impairment and blindness worldwide. Diagnostic uncertainty is greatest in advanced cases, where progressive ulceration and stromal destruction obscure clinical features needed to reliably distinguish between fungal and bacterial etiologies. In these cases, even brief delays in diagnosis can lead to rapid disease progression and irreversible corneal damage. Consequently, substantial effort has been focused on developing diagnostic approaches that shorten the time to definitive diagnosis and enable earlier, targeted treatment. In vivo confocal microscopy (IVCM) can aid highly specific and sensitive diagnosis of corneal ulcers through real-time, non-invasive cellular imaging of the cornea. While the commercial IVCM device, Heidelberg Retinal Tomograph 3 with the Rostock Corneal Module (HRT3-RCM, Heidelberg Engineering), has been successfully evaluated for the diagnosis of microbial keratitis, its widespread adoption has been hindered by high costs (>$75,000), limited field of view (0.4 × 0.4 mm²), and limited imaging speed (30 frames/sec). Furthermore, the requirement for physical corneal contact necessitates specialized training, and the recent discontinuation of the device has left a critical gap in ophthalmic care.

 
This dissertation describes the development of the portable in vivo confocal ophthalmoscope (PICO), a non-contact, cost-effective confocal imaging device designed to address this gap. The microscope device was engineered to meet three primary development goals: (1) high-speed image acquisition, (2) non-contact operation, and (3) low-cost system architecture. Ex vivo imaging studies conducted using freshly excised animal eyes demonstrated the ability of PICO to visualize cellular and morphological features throughout the corneal depth. In addition, compliance analysis studies against the ISO and ANSI laser safety standards were conducted to ensure safe use of the device on human subjects. Collectively, these results establish the technical foundation for translating PICO into a clinically deployable diagnostic tool.
 

Please email Jini at jini@optics.arizona.edu or Kenneth at kmarcelino@arizona.edu for a Zoom link.

Dissertation Defense