Accurate diagnosis of tumors needs much detailed information. However, available single imaging modality cannot provide complete or comprehensive data. Nanomedicine is the application of nanotechnology to medicine, and multimodality imaging based on nanoparticles has been receiving extensive attention. This new hybrid imaging technology could provide complementary information from different ima...

Photoacoustic (PA) imaging, also called optoacoustic imaging, is a new biomedical imaging modality based on the use of laser-generated ultrasound that has emerged over the last decade. It is a hybrid modality, combining the high-contrast and spectroscopic-based specificity of optical imaging with the high spatial resolution of ultrasound imaging. In essence, a PA image can be regarded as an ult...

Optical coherence tomography (OCT) is a well-established optical imaging technique with micrometer-scale resolution. OCT is based on low-coherence interferometry to measure the amplitude of light backscattered by the sample being imaged [1-4]. The most significant impact of OCT is in ophthalmology for in situ examination of the pathologic changes of the retina [5-8] and measurement of the dimen...

Optoacoustic imaging emerged in early 1990s as a new biomedical imaging technology that generates images by illuminating tissues with short laser pulses and detecting resulting ultrasound waves. This technique takes advantage of the spectroscopic approach to molecular imaging, and delivers high-resolution images in the depth of tissue. Resolution of the optoacoustic imaging is scalable, so that...

The inverse transport problem consists of recovering the spatially varying absorption and scattering coefficients of the interior of a highly scattering medium from measurements taken on its boundary [2]. The problem has been widely studied in the context of optical tomography (OT)—a biomedical imaging modality that makes use of multiply-scattered light to visualize structural variations in the...

Microresonator-based frequency comb generation at or near visible wavelengths would enable applications in precise optical clocks, frequency metrology, and biomedical imaging. Comb generation in the visible has been limited by strong material dispersion and loss at short wavelengths, and only very narrowband comb generation has reached below 800 nm. We use the second-order optical nonlinearity ...

Light and optical techniques have made profound impacts on modern medicine, with numerous lasers and optical devices being currently used in clinical practice to assess health and treat disease. Recent advances in biomedical optics have enabled increasingly sophisticated technologies - in particular those that integrate photonics with nanotechnology, biomaterials and genetic engineering. In thi...

We describe results of theoretical and experimental investigations of artifacts that can arise in spectral-domain optical coherence tomography (SD-OCT) and optical frequency domain imaging (OFDI) as a result of sample or probe beam motion. While SD-OCT and OFDI are based on similar spectral interferometric principles, the specifics of motion effects are quite different because of distinct signa...

A major problem for optical biomedical imaging methods, e.g. near-infrared optical tomography (NIROT), using time resolved SPAD sensors is a slow acquisition time, resulting in motion artefacts and decreased patient comfort. We present a new SPAD sensor module optimised for the NIROT application. Dynamic TDC reallocation is employed to reduce the die area occupied by timing circuitry whilst als...

Teknillinen korkeakoulu Informaatio-ja luonnontieteiden tiedekunta Lääketieteellisen tekniikan ja laskennallisen tieteen laitos Article dissertation (summary + original articles) Monograph Faculty Department Field of research Opponent(s) Supervisor Instructor Abstract Keywords diffuse optical imaging, monte carlo, biomedical optics Accurate modelling of tissue properties in diffuse optical imag...