Johannes Rebling

METER Group · Research and Development

Optoacoustic mesoscopy (OAM) retrieves anatomical and functional contrast in vivo at depths not resolvable with optical microscopy. Recent progress on reconstruction algorithms have further advanced its imaging performance to provide high lateral resolution ultimately limited by acoustic diffraction. In this work, a new broadband model‐based OAM (M...

Skull bone development is a dynamic and well‐coordinated process playing a key role in maturation and maintenance of the bone marrow (BM), fracture healing and progression of diseases such as osteoarthritis or osteoporosis. At present, dynamic transformation of the growing bone (osteogenesis) as well as its vascularization (angiogenesis) remain lar...

Background: Microcirculation is essential for skin homeostasis and repair. A variety of growth factors have been identified as important regulators of wound healing. However, direct observation and longitudinal monitoring of skin remodeling in an unperturbed in vivo environment remains challenging. Methods: We report on non-invasive longitudinal im...

Dynamics of tissue revascularization, vessel maturation and remodeling remain poorly understood due to lack of suitable in vivo imaging tools. The new LSOM method offers a versatile tool for tissue engineering and regenerative medicine by empowering label‐free, noninvasive, longitudinal, highthroughput, and quantitative studies of microcirculation...

Optoacoustic microscopy (OAM) retrieves anatomical and functional contrast in vivo at depths not resolvable with optical microscopy. Recent progress on reconstruction algorithms have further advanced its imaging performance to provide high lateral resolution ultimately limited by acoustic diffraction. In this work, we suggest a new broadband model-...

Wound healing is a well‐coordinated process, necessitating efficient formation of new blood vessels. Vascularization defects are therefore a major risk factor for chronic, non‐healing wounds. The dynamics of mammalian tissue revascularization, vessel maturation, and remodeling remain poorly understood due to lack of suitable in vivo imaging tools....

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Acoustic-resolution optoacoustic microscopy (AR-OAM) retrieves anatomical and functional contrast from living tissues at depths not reachable with optical microscopy. The imaging performance of AR-OAM has been advanced with image reconstruction algorithms providing high lateral resolution ultimately limited by acoustic diffraction. In this work, we...

The recently introduced large‐field multifocal illumination (LMI) fluorescence microscopy technique opened new possibilities for transcranial observations of mouse brain dynamics with a unique combination of capillary level resolution and centimeter‐scale field‐of‐view (FOV). Here we report on a new acceleration scheme for LMI based on raster scan...

Optoacoustic (OA) imaging has the capacity to effectively bridge the gap between macroscopic and microscopic realms in biological imaging. High-resolution OA microscopy has so far been performed via point-by-point scanning with a focused laser beam, thus greatly restricting the achievable imaging speed and/or field of view. Herein we introduce mult...

Optoacoustic microscopy (OAM) can image intrinsic optical absorption contrast at depths of several millimeters where state-of-the-art optical microscopy techniques fail due to intense light scattering in living tissues. Yet, wide adoption of OAM in biology and medicine is hindered by slow image acquisition speed, small field of view (FOV), and/or l...

Bone microvasculature plays a paramount role in bone marrow maintenance, development, and hematopoiesis. Studies of calvarian vascular patterns within living mammalian skull with the available intravital microscopy techniques are limited to small scale observations. We developed an optical-resolution optoacoustic microscopy method combined with ult...

In article number 1900070, Daniel Razansky and co‐workers report on a novel optical microscopy concept termed large‐field multifocal illumination (LMI) microscopy based on a beam‐splitting grating and an acousto‐optic deflector synchronized with a high speed camera. The method offers a unique combination between centimeter scale field‐of‐view, enha...

Angiogenesis is critical in bone development and growth. Dense, large-scale, and multi-layered vascular networks formed by thin-walled sinusoidal vessels perfuse the plate bones and play an important role in bone repair. Yet, the intricate functional morphology of skull microvasculature remains poorly understood as it is difficult to visualize usin...

Scanning optical microscopy techniques are commonly restricted to a sub‐millimeter field‐of‐view (FOV) or otherwise employ slow mechanical translation, limiting their applicability for imaging fast biological dynamics occurring over large areas. A rapid scanning large‐field multifocal illumination (LMI) fluorescence microscopy technique is devised...

Functional optoacoustic (OA) imaging assisted with genetically encoded calcium ion indicators (GECIs) holds promise for imaging large-scale neuronal activity at depths and spatiotemporal resolutions not attainable with existing optical microscopic techniques. However, currently available GECIs optimized for fluorescence (FL) imaging lack sufficient...

Efforts to scale neuroimaging towards the direct visualization of mammalian brain-wide neuronal activity have faced major challenges. Although high-resolution optical imaging of the whole brain in small animals has been achieved ex vivo, the real-time and direct monitoring of large-scale neuronal activity remains difficult, owing to the performance...

Real-time visualization of large-scale neural dynamics in whole mammalian brains is hindered with existing neuroimaging methods having limited capacity when it comes to imaging large tissue volumes at high speeds. Optoacoustic imaging has been shown to be capable of real-time three-dimensional imaging of multiple cerebral hemodynamic parameters in...

Video of a concurrent fluorescence and optoacoustic recording of a GCaMP6f-brain. The video shows the changes in fluorescence (planar image) and the optoacoustic signal (MIP, maximum intensity projection) upon injection of the epileptic drug pentylenetetrazol (PTZ, injection at time 0). Clear neuronal activation by PTZ as reflected by calcium chang...

Optoacoustic imaging is a highly scalable and versatile method that can be used for optical resolution (OR) microscopy applications at superficial depth yet can be adapted for tomographic imaging with acoustic resolution at centimeter penetration scales. However, imaging speed of the commonly employed scanning-based microscopy methods is slow as fa...

Accurate image reconstruction in volumetric optoacoustic tomography implies the efficient generation and collection of ultrasound signals around the imaged object. Non‐uniform delivery of the excitation light is a common problem in optoacoustic imaging often leading to a diminished field of view, limited dynamic range and penetration, as well as im...

Mounting experimental evidence reveals severe long-term alterations of bone vasculature following ionizing irradiation procedures. Dense, large-scale, and multi-layered vascular networks formed by thin-walled sinusoidal vessels perfuse the plate bones and are essential for their development, hematopoiesis, and maintenance of the bone marrow. Microv...

We present a hybrid dual‐wavelength optoacoustic and ultrasound bio‐microscope capable of rapid transcranial visualization of morphology and oxygenation status of large‐scale cerebral vascular networks. Imaging of entire cortical vasculature in mice is achieved with single capillary resolution and complemented by simultaneously acquired pulse‐echo...

Radio frequency (RF) catheter ablation is commonly used to eliminate dysfunctional cardiac tissue by heating via an alternating current. Clinical outcomes are highly dependent on careful anatomical guidance, electrophysiological mapping, and careful RF power titration during the procedure. Yet, current treatments rely mainly on the expertise of the...

Contains a detailed description of the model and the optimization procedure of the Virtual Craniotomy algorithm

A critical link exists between pathological changes of cerebral vasculature and diseases affecting brain function. Microscopic techniques have played an indispensable role in the study of neurovascular anatomy and functions. Yet, investigations are often hindered by sub‐optimal trade‐offs between the spatiotemporal resolution, field‐of‐view and typ...

Ultrasound-mediated transcranial images of the brain often suffer from acoustic distortions produced by the skull bone. In high-resolution optoacoustic microscopy, the skull-induced acoustic aberrations are known to impair image resolution and contrast, further skewing the location and intensity of the different absorbing structures. We present a v...

Ultrasound waves propagating in water or soft biological tissue are strongly reflected when encountering the skull, which limits the use of ultrasound-based techniques in transcranial imaging and therapeutic applications. Current knowledge on the acoustic properties of the cranial bone is restricted to far-field observations, leaving its near-field...

The skull bone, a curved solid multilayered plate protecting the brain, constitutes a big challenge for the use of ultrasound-mediated techniques in neuroscience. Ultrasound waves incident from water or soft biological tissue are mostly reflected when impinging on the skull. To this end, skull properties have been characterized for both high-intens...

Whole-body optical imaging of post-embryonic stage model organisms is a challenging and long sought-after goal. It requires a combination of high-resolution performance and high-penetration depth. Optoacoustic (photoacoustic) mesoscopy holds great promise, as it penetrates deeper than optical and optoacoustic microscopy while providing high spatial...

Frequency characteristics of ultrasound detectors used in optoacoustic tomography have a major impact on imaging performance. It is common practice to select transducers based on their sensitivity at the central frequency and under normal incidence. However, the bandwidth and angular sensitivity play an equally important role in establishing the qu...

The acoustically-mismatched skull bone poses significant challenges for the application of ultrasonic and optical techniques in neuroimaging, still typically requiring invasive approaches using craniotomy or skull thinning. Optoacoustic imaging partially circumvents the acoustic distortions due to the skull because the induced wave is transmitted o...

The angular reception performance of ultrasound transducers is a critical parameter in the design of a photoacoustic imaging system. Here we present a quantitative comparison between cMUT and PZT ultrasound transducers. We analyze the requirements of an ideal transducer for conventional pulse-echo ultrasound versus those of a photoacoustic imaging...

It has been well recognized that the presence of a skull imposes harsh restrictions on the use of ultrasound and optoacoustic techniques in the study, treatment and modulation of the brain function. We propose a rigorous modeling and experimental methodology for estimating the insertion loss and the elastic constants of the skull over a wide range...

Despite the great promise behind the recent introduction of optoacoustic technology into the arsenal of small-animal neuroimaging methods, a variety of acoustic and light-related effects introduced by adult murine skull severely compromise the performance of optoacoustics in transcranial imaging. As a result, high-resolution noninvasive optoacousti...

To achieve optimal, diffraction limited images with the best possible resolution has always been a challenging topic and an important goal in science and in biophotonics in particular. Although many new techniques to acquire superesolution images were developed in the last decade, unwanted aberrations often still compromise the resolution and brigh...

Rotational spectra of a chiral epoxy ester, methyl glycidate, were measured using a chirped-pulse and a cavity based Fourier transform microwave spectrometer. The two lowest energy conformers where the epoxy oxygen and the ester oxygen atoms are in the syn and anti relative orientation with respect to each other were identified experimentally. Spec...

We investigate a power tunable junction formed by two interacting spatial solitons self-trapped in nematic liquid crystals. By launching a counter-propagating copolarized probe we assess the guided-wave behavior induced by the solitons and demonstrate a novel all-optical switch. Varying soliton power the probe gets trapped into one or two or three...

This work presents a detailed investigation of the properties and attractive interaction of spatial solitons in nematic liquid crystals for all-optical switching devices. This includes a description of basic properties such as their multimode behavior, as well as their power dependent interactions and signal steering. Furthermore, the temporal perf...

This letter reports the first experimental observation, to our knowledge, of optical vector solitons composed of two incoherently coupled vortex components. We employ nematic liquid crystal to generate stable vector solitons with counterrotating vortices and hidden vorticity. In contrast, the solitons with explicit vorticity and corotating vortex c...