Multimodal optical imaging platform for the early diagnosis for oral neoplasia

Early diagnosis is critical to reducing the global burden of oral cancer. In the US, 65% of oral cancer patients are diagnosed after regional metastasis; these patients have a 50% five-year mortality compared to 17% for those with localized disease. A major reason for late diagnosis is that clinicians are unable to accurately distinguish neoplastic lesions, which require treatment, from benign lesions. Furthermore, clinicians are unable to accurately select to biopsy the site with the worst diagnosis within a larger lesion. Please download the file below for full content

Real-time video mosaicing with a high-resolution microendoscope

Microendoscopes allow clinicians to view subcellular features in vivo and in real-time, but their field-of-view is inherently limited by the small size of the probe's distal end. Video mosaicing has emerged as an effective technique to increase the acquired image size. Current implementations are performed post-procedure, which removes the benefits of live imaging. In this manuscript we present an algorithm for real-time video mosaicing using a low-cost high-resolution microendoscope. We present algorithm execution times and show image results obtained from in vivo tissue

A Lateral Flow Assay for Quantitative Detection of Amplified HIV-1 RNA

Although the accessibility of HIV treatment in developing nations has increased dramatically over the past decade, viral load testing to monitor the response of patients receiving therapy is often unavailable. Existing viral load technologies are often too expensive or resource-intensive for poor settings, and there is no appropriate HIV viral load test currently available at the point-of-care in low resource settings. Here, we present a lateral flow assay that employs gold nanoparticle probes and gold enhancement solution to detect amplified HIV RNA quantitatively. Preliminary results show that, when coupled with nucleic acid sequence based amplification (NASBA), this assay can detect concentrations of HIV RNA that match the clinically relevant range of viral loads found in HIV patients. The lateral flow test is inexpensive, simple and rapid to perform, and requires few resources. Our results suggest that the lateral flow assay may be integrated with amplification and sample preparation technologies to serve as an HIV viral load test for low-resource settings

Development of a multimodal foveated endomicroscope for the detection of oral cancer

A multimodal endomicroscope was developed for cancer detection that combines hyperspectral and confocal imaging through a single foveated objective and a vibrating optical fiber bundle. Standard clinical examination has a limited ability to identify early stage oral cancer. Optical detection methods are typically restricted by either achievable resolution or a small field-of-view. By combining high resolution and widefield spectral imaging into a single probe, a device was developed that provides spectral and spatial information over a 5 mm field to locate suspicious lesions that can then be inspected in high resolution mode. The device was evaluated on ex vivo biopsies of human oral tumors

Development of a single-board computer high-resolution microendoscope (PiHRME) to increase access to cervical cancer screening in underserved areas

Over 85% of cervical cancer deaths occur in developing countries.1 Even though the early detection and treatment of cervical precancerous lesions has been shown to prevent invasive cervical cancer, limited resources make it difficult to implement standard cervical cancer screening methods, such as the Pap Smear, in low-resource areas. Instead, many developing countries rely on the visual inspection of the cervix with acetic acid (VIA) to help identify precancerous and cancerous lesions. While VIA has a high sensitivity (82.14%), it has a poor specificity (50.00%), resulting in the overtreatment of women and misallocation of limited resources.2 Recent studies have shown that combining VIA with high-resolution microendoscope (HRME) imaging increases the specificity of cervical cancer screening.3-4 The HRME is a low-cost imaging system (~$2,100) that allows the user to image epithelial tissue in vivo at sub-cellular resolutions at the point-of-care. The current HRME imaging system is also accompanied with automatic image analysis software to distinguish normal and low-grade lesions from high-grade precancerous and cancerous lesions of the cervix. Please click Additional Files below to see the full abstract

AutoSyP: A Low-Cost, Low-Power Syringe Pump for Use in Low-Resource Settings

This article describes the design and evaluation of AutoSyP, a low-cost, low-power syringe pump intended to deliver intravenous (IV) infusions in low-resource hospitals. A constant-force spring within the device provides mechanical energy to depress the syringe plunger. As a result, the device can run on rechargeable battery power for 66 hours, a critical feature for low-resource settings where the power grid may be unreliable. The device is designed to be used with 5- to 60-mL syringes and can deliver fluids at flow rates ranging from 3 to 60 mL/hour. The cost of goods to build one AutoSyP device is approximately $500. AutoSyP was tested in a laboratory setting and in a pilot clinical study. Laboratory accuracy was within 4% of the programmed flow rate. The device was used to deliver fluid to 10 healthy adult volunteers and 30 infants requiring IV fluid therapy at Queen Elizabeth Central Hospital in Blantyre, Malawi. The device delivered fluid with an average mean flow rate error of −2.3% ± 1.9% for flow rates ranging from 3 to 60 mL/hour. AutoSyP has the potential to improve the accuracy and safety of IV fluid delivery in low-resource settings

Rollerball microendoscope for mosaicking in high-resolution oral imaging

Only 40% of oral cancers are diagnosed at an early, localized stage, when treatment is most effective [1]. Thus, implementing diagnostic imaging tools for early detection of highgrade dysplasia and cancer may help improve the survival rate of oral cancer patients [2]. The highresolution microendoscope (HRME) is a compact, portable, fiberbased imaging device that can image cell nuclei in tissue labeled with the fluorescent contrast agent proflavine [3]. The HRME allows clinicians to noninvasively image the size, shape and distribution of epithelial cell nuclei in vivo, enabling realtime evaluation of potentially neoplastic lesions [3]. The primary limitation of the HRME is the small field of view of its fiber probe (720 μm), which makes it timeconsuming to examine large areas of tissue. Mosaicking algorithms have previously been implemented to allow realtime generation of image mosaics during HRME imaging, thus interrogating a larger field of view than the fiber probe’s diameter [4]. However, this approach has had limited success in vivo due to the practical difficulty of translating the fiber probe across the tissue in a smooth, controlled manner in order for the mosaicking software to function properly. Here we report the construction and initial testing of a rollerball HRME probe that permits smooth, rolling translation across the tissue surface while maintaining image quality with subcellular resolution. The rollerball HRME consists of a standard HRME probe interfaced with a rollerball mechanism. The mechanism is composed of two 5mm sapphire ball lenses enclosed within a 3D printed penlike casing. The ball lenses serve as an optical relay, while the distal ball lens also serves as a rolling contact point with the tissue surface. Figure 1 shows the use of the rollerball HRME to generate a realtime mosaic of a calibration target (field finder slide) as it rolls across the surface of the target. Figure 2 shows the use of the rollerball HRME to generate a realtime mosaic showing cell nuclei on the lateral tongue of a healthy volunteer as it rolls across the tissue surface. The rollerball HRME will allow clinicians to more rapidly examine large areas of tissue with subcellular resolution, potentially aiding in the early detection of highgrade oral dysplasia and cance. Please click Additional Files below to see the full abstract