Development of point-of-care medical devices for improved healthcare
Translation of research from 'Lab-to-Land' is an essential requirement for efficient healthcare management in developing countries like India. Necessity of affordable, rapid and reliable technologies is fast increasing in the field of medical diagnosis. Recent research has shown significant potential of optics and photonics technology for rapid and reliable diagnosis of diseases. Optical techniques are inherently advantageous for being rapid and sensitive and also for their capability in providing minimally invasive disease diagnosis. We at LBAD, are dedicated towards research and development of point-of care devices based on optical imaging and spectroscopy for healthcare.
Biophotonics was initially explored at LBAD for understanding laser/ light tissue interaction. The transformation of a normal tissue towards malignancy results in several biochemical changes which are reflected in the optical signatures obtained from the tissue. Subsequently laser- induced fluorescence (LIF) was explored to identify characteristic differences in the fluorescence emitted from normal and malignant tissue sites. Further, intensive studies to identify the excitation wavelength(s) which can lead to large differences in the fluorescence characteristics of normal and diseased tissue sites and development of algorithms which can exploit these differences for diagnosis were performed.
Building on the expertise developed through these previous studies, LBAD has developed three point-of-care devices for applications in actual clinical settings - TuBerculoScope, OncoVision (a vision enhanced module) and OncoDiagnoScope. These devices are targeted for early diagnosis of two ubiquitous diseases in India- Tuberculosis and cancer (oral and cervical). TuBerculoScope is a portable and affordable fluorescence imaging device that is intended for rapid detection of tuberculosis causing bacteria in dye-stained sputum smears. OncoVision helps identifying oral tissue transforming towards malignancy based on the differences in the fluorescence emission characteristics from an abnormal and normal tissue type. OncoDiagnoScope is a point-of-care optical device for non-invasive screening of oral cavity for abnormalities leading to cancer. It performs fluorescence and diffuse reflectance spectroscopy based characterization of oral tissue into normal and abnormal types (tissues transforming towards cancer).
(1) TuBerculoScope - A low cost and compact fluorescence imaging device for rapid detection of tuberculosis
TuBerculoScope, developed at RRCAT, is a low cost, compact and user friendly fluorescence imaging device useful for rapid detection of pulmonary tuberculosis (TB). The device displays fluorescence images of Mycobacterium tuberculi bacteria (Mtb) from a patient’s sputum smeared on a microscope glass slide following its staining with an appropriate fluorescent dye and illumination with a light emitting diode (LED).
A Graphical User Interface (GUI) software enables hardware control of the device and automated counting of the Mtb bacteria in the field of view of the microscope objective. The device has significantly low cost as compared to presently used general purpose fluorescence microscope routinely used for TB diagnosis in clinical pathology labs.
TB is a major health concern in India. Fluorescence microscopy is one of the WHO recommended methods for initial diagnosis of TB. However, the utility of this method largely remains inaccessible in rural and developing areas due to prohibitive cost of the equipment (fluorescence microscope) and its maintenance apart from the cost of trained technicians and laboratory infrastructure. Deployment of TuBerculoScope will facilitate convenient and low-cost monitoring of TB patients resulting in better patient follow up which is an important step in TB eradication.
The technology of the device has been transferred to M/s RTK Meditech, Indore. One unit of the device has been deployed at Homi Bhabha Cancer Hospital, Varanasi and the other at the Department of Biochemistry, Banaras Hindu University, Varanasi where they are undergoing clinical validation.
TuBerculoScope along with the Graphic User Interface (GUI) software
(2) OncoVision – A low cost fluorescence imaging tool for identification of malignant and potentially malignant lesions of oral cavity
OncoVision is a simple, hand-held device for real-time, non-contact and in-situ imaging of fluorescence from superficial tissues like human oral cavity, cervix, skin etc. intended for improved visual assessment.
The device utilizes the fact established by previous studies that the fluorescence emission properties of a tissue transforming to a cancerous stage is different from that of a healthy tissue. Using this instrument, regions of lesions in oral, cervical or skin can be better identified against the healthy tissues based on their natural characteristics in response to light. The method involves shining light from the multiple UV light emitting diodes (LEDs), onto the tissues for inducing fluorescence in the native tissues. The fluorescence emitted from the tissues is detected by a CCD camera attached to a high-pass optical filter to generate two dimensional fluorescence spectral images. All the components of the system, including the LEDs, the CCD and the optical high-pass filter are accommodated in an in-house fabricated cylindrical case. The device is powered through a USB port. The system facilitates acquisition of fluorescence emission information from larger areas of the tissue surface for the purpose of rapid screening of the oral cavity and identifying the abnormal regions.
OncoVision can easily be augmented with the point-spectroscopy based system, the ‘OncoDiagnoScope’, for simultaneous use. The synergistic use of the two devices may lead to better management of cancer in a real-time diagnostic setting. This is because while the former allows better visual identification of regions of lesions (often time missed by visual examination under white light illumination) against the healthy tissues, the later can be used to quantitatively ascertain the pathology of these lesions.
OncoVision -Vision Enhancement Module
(3) OncoDiagnoScope - A stand-alone, field-usable optical spectroscopy based point-of-care device for instant non-invasive diagnosis of oral cavity cancer
OncoDiagnoScope, developed at LBAD, is a compact and portable, easy to use, optical spectroscopy based health-care device to help doctors non-invasively detect, in real-time, whether any pre-cancerous or cancerous lesion is present in the oral cavity of the subject he is examining.
This point-of-care device uses two types of light (fluorescence and reflectance) returned from the tissue to determine its tissue type without disturbing or destroying the tissue. The method involves putting a fiber optic probe in contact with the suspected tissue site in the oral cavity. The light coming out of the tissue is captured and fed to the integrated tablet computer where it is analyzed by a specially developed machine-learning algorithm which can instantly determine whether the tissue is cancerous or not and gives the result on the computer screen in real-time. Further, it provides quantitative diagnosis unlike the biopsy results which is qualitative and subjective, as a human being interprets the results looking at the tissue slides. The entire investigation procedure per subject, using this device, takes less than 15 minutes as compared to several hours required by the conventional procedure of biopsy followed by histopathology.
The technology of this device has been transferred to M/s Applied Optical Technologies Pvt. Ltd., Ambernath, Thane. The device is also fabricated by Electronics Corporation of India Ltd. (ECIL), Hyderabad through technology absorption and available for supply. Units of OncoDiagnoScope have been given to Homi Bhabha Cancer hospital, Sangrur, Homi Bhabha Cancer Hospital, Varanasi and S.S. Hospital & Research Center, Patna for large scale clinical validation. OncoDiagnoScope has also been validated in several cancer screening camps as well various hospitals including Tata Memorial Hospital, Mumbai. Validation of the device, on around 3000 patients with different oral tissue abnormalities as on date, have shown that the device can detect cancer with an accuracy of over 90%.
OncoDiagnoScope along with the Graphic User Interface (GUI) software
