Although the patients with cancer on pancreas or pancreaticobiliary duct have been increased, it is very difficult to detect and to treat the pancreatic cancer because of its low accessibility and obtuseness. The pancreatic cancer has been diagnosed using ultrasonography, blood test, CT, endoscopic retrograde cholangiopancreatography (ERCP), endoscopic ultrasonography (EUS) and etc. Normally, light can be delivered to the target by optical fibers through the ERCP or EUS. Diffusing optical fibers have been developed with various methods. However, many of them have mechanical and biological problems in the use of small-bend-radius apparatus or in tissue area. This study developed a therapeutic cylindrical diffusing optical fiber probe (CDOFP) for ERCP and EUS which has moderate flexibility and solidity to treat the cancer on pancreaticobiliary duct or pancreas. The CDOFP consists of a biocompatible Teflon tube and multimode glass fiber which has diffusing area processed with laser and high refractive index resin. The CDOFP was characterized to investigate the clinical feasibility and other applications of light therapy using diffusing optical fiber. The results presented that the CDOFP may be used in clinic by combining with endoscopic method, such as ERCP or EUS, to treat cancer on pancreas and pancreaticobiliary duct.
A stereoscopic imaging modality was developed for the application of ophthalmology surgical microscopes. A previous study has already introduced a single-channel stereoscopic video imaging modality based on a transparent rotating deflector (SSVIM-TRD), in which two different view angles, image disparity, are generated by imaging through a transparent rotating deflector (TRD) mounted on a stepping motor and is placed in a lens system. In this case, the image disparity is a function of the refractive index and the rotation angle of TRD. Real-time single-channel stereoscopic ophthalmology microscope (SSOM) based on the TRD is improved by real-time controlling and programming, imaging speed, and illumination method. Image quality assessments were performed to investigate images quality and stability during the TRD operation. Results presented little significant difference in image quality in terms of stability of structural similarity (SSIM). A subjective analysis was performed with 15 blinded observers to evaluate the depth perception improvement and presented significant improvement in the depth perception capability. Along with all evaluation results, preliminary results of rabbit eye imaging presented that the SSOM could be utilized as an ophthalmic operating microscopes to overcome some of the limitations of conventional ones.
Tibial defect is very common musculoskeletal disorder which makes patient painful and uncomfortable. Many studies
about bone regeneration tried to figure out fast bone healing on early phase. It is already known that low level laser
therapy (LLLT) is very convenient and good for beginning of bone disorder. However, light scattering and absorption
obstruct musculoskeletal therapy which need optimal photon energy delivery. This study has used an interstitial laser
probe (ILP) to overcome the limitations of light penetration depth and scattering. Animals (mouse, C57BL/6) were
divided into three groups: laser treated test group 1 (660 nm; power 10 mW; total energy 5 J) and test group 2 (660 nm;
power 20 mW; total energy 10 J); and untreated control group. All animals were taken surgical operation to make tibial
defect on right crest of tibia. The test groups were treated every 48 hours with ILP. Bone volume and X-ray attenuation
coefficient were measured on 0, 14th and 28th day with u-CT after treatment and were used to evaluate effect of LLLT.
Results show that bone volume of test groups has been improved more than control group. X-ray attenuation coefficients
of each groups have slightly different. The results suggest that LLLT combined with ILP may affect on early phase of
bone regeneration and may be used in various musculoskeletal disease in deep tissue layer.
As the interest in skin was increased, number of studies on skin care also have been increased. The reduction of skin
density is one of the symptoms of skin aging. It reduces elasticity of skin and becomes the reason of wrinkle formation.
Low level laser therapy (LLLT) has been suggested as one of the effective therapeutic methods for skin aging as in
hasten to change skin density. This study presents the effect of a minimally invasive laser needle system (MILNS)
(wavelength: 660nm, power: 20mW) in skin density. Rabbits were divided into three groups. Group 1 didn't receive any
laser stimulation as a control group. Group 2 and 3 as test groups were exposed to MILNS with energy of 8J and 6J on
rabbits' dorsal side once a week, respectively. Skin density of rabbits was measured every 12 hours by using an
ultrasound skin scanner.
Stereoscopic retinal image can effectively help doctors. Most of stereo imaging surgical microscopes are based on dual optical channels and benefit from dual cameras in which left and right cameras capture corresponding left and right eye views. This study developed a single-channel stereoscopic retinal imaging modality based on a transparent rotating deflector (TRD). Two different viewing angles are generated by imaging through the TRD which is mounted on a motor synchronized with a camera and is placed in single optical channel. Because of the function of objective lens in the imaging modality which generate stereo-image from an object at its focal point, and according to eye structure, the optical set up of the imaging modality can compatible for retinal imaging when the cornea and eye lens are engaged in objective lens.
This study investigates the feasibility of an endoscopic laser speckle imaging modality (ELSIM) in the measurement of perfusion of flowing fluid in optical bone tissue phantom(OBTP). Many studies suggested that the change of cochlear blood flow was correlated with auditory disorder. Cochlear microcirculation occurs under the 200μm thickness bone which is the part of the internal structure of the temporal bone. Concern has been raised regarding of getting correct optical signal from hard tissue. In order to determine the possibility of the measurement of cochlear blood flow under bone tissue using the ELSIM, optical tissue phantom (OTP) mimicking optical properties of temporal bone was applied.
This paper introduces a stereoscopic video imaging modality based on a transparent rotating deflector (TRD). Sequential two-dimensional (2D) left and right images were obtained by rotating the TRD on a stepping motor synchronized with a complementary metal-oxide semiconductor camera, and the components of the imaging modality were controlled through general purpose input/output ports using a microcontroller unit. In this research, live stereoscopic videos were visualized on a personal computer by both active shutter 3D and passive polarization 3D methods. The imaging modality was characterized by evaluating the stereoscopic video image generation, rotation characteristics of the TRD. The level of 3D conception was estimated in terms of simplified human stereovision. The results show that singlechannel stereoscopic video imaging modality has the potential to become an economical compact stereoscopic device as the system components are amenable to miniaturization; and could be applied in a wide variety of fields.
Although the mechanism of low level laser therapy (LLLT) is unclear, many studies demonstrated the positive clinical performance of LLLT for skin rejuvenation. An increase in dermal collagen plays an important role in skin rejuvenation and wound healing. This study aimed to investigate collagen generation after interstitial low level laser stimulation (ILLS). Rabbits were divided into two groups: surfacing irradiation and minimally invasive irradiation. 660nm diode laser of 20mW with 10J, 13J and 15J was applied to the backside of rabbits. Collagen formation was evaluated with ultrasound skin scanner every 12 hours. Results shows that ILLS groups have denser collagen density than surfacing groups.