Thermal Stimulation of the Retina Reduces Bruch's Membrane Thickness in Age Related Macular Degeneration Mouse Models.

Purpose: To investigate the effect of thermal stimulation of the retina (TS-R) on Bruch's membrane (BrM) thickness in age-related macular degeneration (AMD) mouse models as a novel concept for the prophylaxis and treatment of dry AMD.

Methods: Two knockout AMD mouse models, B6.129P2-Apoe/J (ApoE-/-) and B6.

Release of Different Cell Mediators During Retinal Pigment Epithelium Regeneration Following Selective Retina Therapy.

Purpose: To investigate the effect of selective retina therapy (SRT) on the release of AMD-relevant cell mediators, such as matrix metalloproteinases (MMPs), VEGF, and pigment epithelium derived factor (PEDF) using different laser spot sizes and densities.

Methods: Porcine RPE-choroid explants were treated with a pulsed 532 nm Nd:YAG laser using (1) large spot sizes, (2) small spot sizes with a high-density (hd) treatment, and (3) small spot sizes with a low-density (ld) treatment. Explants were cultivated in modified Ussing chambers.

Novel endoscope with increased depth of field for imaging human nasal tissue by microscopic optical coherence tomography.

Intravital microscopy (IVM) offers the opportunity to visualize static and dynamic changes of tissue on a cellular level. It is a valuable tool in research and may considerably improve clinical diagnosis. In contrast to confocal and non-linear microscopy, optical coherence tomography (OCT) with microscopic resolution (mOCT) provides intrinsically cross-sectional imaging.

Expression of heat shock protein 70 and cell death kinetics after different thermal impacts on cultured retinal pigment epithelial cells.

Recent technologies are broadening the possibility to treat the retinal pigment epithelium (RPE) with different thermal impacts, from sublethal to lethal ranges. Thus temperature-dependent subcellular molecular responses need to be elucidated in more detail. In this study, RPE cell viability and expression of heat shock protein 70 (Hsp70) were investigated after thermal irradiation with different temperature increase using an in-vitro model.

Comment on "Retinal pulse wave velocity measurement using spectral-domain optical coherence tomography".

This paper comments on the article "Retinal pulse wave velocity measurement using spectral-domain optical coherence tomography" by Qian Li et al. The authors propose a method to determine the pulse wave velocity in retinal arteries and veins. This method should enable a noninvasive determination of biomechanical properties of the vessel network, particularly the elasticity of the vessel walls.

Continuous-wave Thulium Laser for Heating Cultured Cells to Investigate Cellular Thermal Effects.

An original method to heat cultured cells using a 1.94 µm continuous-wave thulium laser for biological assessment is introduced here. Thulium laser radiation is strongly absorbed by water, and the cells at the bottom of the culture dish are heated through thermal diffusion.

Reduction of frame rate in full-field swept-source optical coherence tomography by numerical motion correction [Invited].

Full-field swept-source optical coherence tomography (FF-SS-OCT) was recently shown to allow new and exciting applications for imaging the human eye that were previously not possible using current scanning OCT systems. However, especially when using cameras that do not acquire data with hundreds of kHz frame rate, uncorrected phase errors due to axial motion of the eye lead to a drastic loss in image quality of the reconstructed volumes. Here we first give a short overview of recent advances in techniques and applications of parallelized OCT and finally present an iterative and statistical algorithm that estimates and corrects motion-induced phase errors in the FF-SS-OCT data.

Biomedical optics centers: forty years of multidisciplinary clinical translation for improving human health.

Despite widespread government and public interest, there are significant barriers to translating basic science discoveries into clinical practice. Biophotonics and biomedical optics technologies can be used to overcome many of these hurdles, due, in part, to offering new portable, bedside, and accessible devices. The current JBO special issue highlights promising activities and examples of translational biophotonics from leading laboratories around the world.

In vivo optical imaging of physiological responses to photostimulation in human photoreceptors.

Noninvasive functional imaging of molecular and cellular processes of vision may have immense impact on research and clinical diagnostics. Although suitable intrinsic optical signals (IOSs) have been observed ex vivo and in immobilized animals in vivo, detecting IOSs of photoreceptor activity in living humans was cumbersome and time consuming. Here, we observed clear spatially and temporally resolved changes in the optical path length of the photoreceptor outer segment as a response to an optical stimulus in the living human eye.

Aberration-free volumetric high-speed imaging of in vivo retina.

Certain topics in research and advancements in medical diagnostics may benefit from improved temporal and spatial resolution during non-invasive optical imaging of living tissue. However, so far no imaging technique can generate entirely diffraction-limited tomographic volumes with a single data acquisition, if the target moves or changes rapidly, such as the human retina. Additionally, the presence of aberrations may represent further difficulties.

Lesion strength control by automatic temperature guided retinal photocoagulation.

Laser photocoagulation is an established treatment for a variety of retinal diseases. However, when using the same irradiation parameter, the size and strength of the lesions are unpredictable due to unknown inter- and intraindividual optical properties of the fundus layers. The aim of this work is to investigate a feedback system to generate desired lesions of preselectable strengths by automatically controlling the irradiation time.

Retinal sensitivity after selective retina therapy (SRT) on patients with central serous chorioretinopathy.

Purpose: To assess retinal sensitivity after selective retina therapy (SRT) in patients with central serous chorioretinopathy (CSCR).

Methods: Seventeen eyes of 17 patients with CSCR lasting longer than 3 months were treated with SRT (wavelength 527 nm Nd: YLF laser, 50-150 μJ/pulse, spot diameter 200 μm). Measurement of best-corrected visual acuity (BCVA), optical coherence tomography, fluorescence angiography, and microperimetry (MAIA™) were conducted before, and 1 and 3 months after treatment.

Retinal Pigment Epithelium Responses to Selective Retina Therapy in Mouse Eyes.

Purpose: To investigate the characteristics of retinal pigment epithelium (RPE) and retinal damage induced by selective retina therapy (SRT) in mice, and to elucidate longitudinal changes in RPE cells.

Methods: C57BL/6J mice received SRT and continuous-wave laser photocoagulation (cwPC). The cell death pattern was evaluated using TUNEL assay, and proliferative potential of the RPE cells was evaluated using 5-ethynyl-2'-dexoyuridine (EdU) assay.

Selective Retina Therapy in Patients With Chronic Central Serous Chorioretinopathy: A Pilot Study.

We evaluated visual outcomes, changes of maximum macular thickness (MMT) and subretinal fluid (SRF), and safety in patients with chronic central serous chorioretinopathy (CSC) after treatment with selective retina therapy (SRT). Retrospective cohort study of patients with chronic CSC presenting to a university-based hospital from January 2014 through January 2015 was conducted. A total of 12 eyes of 12 patients with chronic CSC lasting for at least 3 months was recruited.

Safety and efficacy of selective retina therapy (SRT) for the treatment of diabetic macular edema in Korean patients.

Purpose: Selective retina therapy (SRT) stimulates retinal pigment epithelium (RPE) cell migration and proliferation into irradiated areas. The objective of this study was to evaluate the efficacy and safety of SRT in Korean patients with clinically significant diabetic macular edema (DME).

Methods: Prospective non-randomized interventional case series study.

A Comparative Study of Retinal Function in Rabbits after Panretinal Selective Retina Therapy versus Conventional Panretinal Photocoagulation.

Purpose. This study evaluates functional changes in electroretinographic findings after selective retina therapy (SRT) compared to panretinal photocoagulation (PRP) in rabbits. Methods.

Full-field speckle interferometry for non-contact photoacoustic tomography.

A full-field speckle interferometry method for non-contact and prospectively high speed Photoacoustic Tomography is introduced and evaluated as proof of concept. Thermoelastic pressure induced changes of the objects topography are acquired in a repetitive mode without any physical contact to the object. In order to obtain high acquisition speed, the object surface is illuminated by laser pulses and imaged onto a high speed camera chip.

Functional evaluation using multifocal electroretinogram after selective retina therapy with a microsecond-pulsed laser.

Purpose: To evaluate the changes of retinal function with multifocal electroretinogram (mfERG), and estimate the association between functional and structural changes after selective retina therapy (SRT) with microsecond-pulsed laser in comparison to continuous wave laser photocoagulation (cwPC).

Methods: Selective retina therapy and cwPC were applied with 10 × 10 shots and 1/2 lesion-width on the retina in the right and left eyes of 20 healthy Chinchilla Bastard rabbits, respectively. Optical coherence tomography (OCT), fundus fluorescein angiography (FFA), and mfERG were performed before, and on days 1, 7, and 30 after both laser treatments.

Protective effect of a laser-induced sub-lethal temperature rise on RPE cells from oxidative stress.

Recently introduced new technologies that enable temperature-controlled laser irradiation on the RPE allowed us to investigate temperature-resolved RPE cell responses. In this study we aimed primarily to establish an experimental setup that can realize laser irradiation on RPE cell culture with the similar temperature distribution as in the clinical application, with a precise time/temperature history. With this setup, we conducted investigations to elucidate the temperature-dependent RPE cell biochemical responses and the effect of transient hyperthermia on the responses of RPE cells to the secondary-exposed oxidative stress.

A novel sponge-based wound stasis dressing to treat lethal noncompressible hemorrhage.

Background: Noncompressible hemorrhage is the leading cause of preventable death caused by hemorrhage on the battlefield. Currently, there are no hemostatic agents with the ability to control noncompressible hemorrhage. A wound stasis dressing based upon rapidly expanding cellulose minisponges (MS) was developed and tested in a lethal noncompressible model in swine, by fully transecting subclavian artery and vein.

Photochemical internalisation: the journey from basic scientific concept to the threshold of clinical application.

Efficient delivery of therapeutic agents to subcellular targets is a major challenge in pharmacology. Physical properties including size and charge may adversely affect the cellular uptake of molecules, and consequently reduce the accessibility of intracellular targets. For example macromolecules, which do not pass freely through the phospholipid membrane, are internalised via endocytosis and subsequently retained in endosomes or lysosomes before enzymatic degradation or cell efflux.

Mechanical property characterization of electrospun recombinant human tropoelastin for vascular graft biomaterials.

The development of vascular grafts has focused on finding a biomaterial that is non-thrombogenic, minimizes intimal hyperplasia, matches the mechanical properties of native vessels and allows for regeneration of arterial tissue. In this study, the structural and mechanical properties and the vascular cell compatibility of electrospun recombinant human tropoelastin (rTE) were evaluated as a potential vascular graft support matrix. Disuccinimidyl suberate (DSS) was used to cross-link electrospun rTE fibers to produce a polymeric recombinant tropoelastin (prTE) matrix that is stable in aqueous environments.

Structural and cellular characterization of electrospun recombinant human tropoelastin biomaterials.

An off-the-shelf vascular graft biomaterial for vascular bypass surgeries is an unmet clinical need. The vascular biomaterial must support cell growth, be non-thrombogenic, minimize intimal hyperplasia, match the structural properties of native vessels, and allow for regeneration of arterial tissue. Electrospun recombinant human tropoelastin (rTE) as a medial component of a vascular graft scaffold was investigated in this study by evaluating its structural properties, as well as its ability to support primary smooth muscle cell adhesion and growth.

Light-guided lumpectomy: device and case report.

We describe the development, design, fabrication, and testing of an optical wire to assist in the surgical removal of small lesions during breast-conserving surgery. We modify a standard localization wire by adding a 200-μm optical fiber alongside it; the resulting optical wire fit through an 18 gauge needle for insertion in the breast. The optical wire is anchored in the lesion by a radiologist under ultrasonic and mammographic guidance.

Hemostasis after liver resection improves after single application of albumin and argon beam coagulation.

Background: Bleeding from the liver surface is common after hepatic resection. Animal studies have demonstrated superiority of argon beam coagulation (ABC) and 38% human serum albumin when applied together after partial liver resection when compared to ABC alone. There are no data addressing the combination of albumin and argon beam coagulation (ABCA) applied to the bleeding liver after resection in humans.