Optical imaging method to quantify spatial dose variation due to the electron return effect in an MR‐linac

AbstractIntraoperative Optical Imaging (IOI) is a neuro-imaging technique that allows the visualization of changes in optical properties of the brain cortex. Recent developments enhanced the method regarding the robustness under intraoperative conditions. However, the necessity of additional hardware still limits the use in the operating room (OR). Since modern surgical microscopes are potentially equipped with all required hardware for imaging, we investigated the possible use of such standard RGB camera for IOI. Measurements were performed on eight patients. Changes in optical properties of the cortical surface were acquired with a monochrome CCD camera (AxioCam MRm) and simultaneously with a standard RGB camera (Trio 610). Maps of cortical activity were calculated from the image data and the quality of these maps was assessed with a spatial signal-to-noise ratio. Activity maps calculated from AxioCam MRm data showed highest SNR in six out of eight patients. In two patients the activity map calculated from Trio 610 red channel performed best overall. The Trio 610 maps calculated from red channel data performed best in three out of eight cases like the activity maps calculated from green channel data, whereas the activity map calculated from blue channel data performed best in only two cases. If the color channel with the highest SNR is chosen in each patient for comparison to AxioCam MRm, the median of the SNR (SNRAxioCam/SNRBestColorChannel) is 84 % (Quartile 1 (Q1): 78 %, Quartile 3 (Q3): 99%). Results reveal that the integration of the Intraoperative Optical Imaging method into the OR and surgical workflow can be further improved by using RGB camera equipment. A robust identification of somato-sensory areas seems possible. Due to the gain of information from different wavelength bands the need for intelligent evaluation algorithms is increased and should therefore be topic of future research.

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Optical imaging of single-protein size, charge, mobility, and binding

Nature Communications ◽

10.1038/s41467-020-18547-w ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Guangzhong Ma ◽

Zijian Wan ◽

Yunze Yang ◽

Pengfei Zhang ◽

Shaopeng Wang ◽

...

Keyword(s):

Optical Imaging ◽

Single Molecule ◽

Near Field ◽

Disease Diagnosis ◽

Imaging Method ◽

Charge Mobility ◽

Single Molecule Level ◽

Protein Size ◽

Flexible Polymer ◽

Detection And Identification

Abstract Detection and identification of proteins are typically achieved by analyzing protein size, charge, mobility and binding to antibodies, which are critical for biomedical research and disease diagnosis and treatment. Despite the importance, measuring these quantities with one technology and at the single-molecule level has not been possible. Here we tether a protein to a surface with a flexible polymer, drive it into oscillation with an electric field, and image the oscillation with a near field optical imaging method, from which we determine the size, charge, and mobility of the protein. We also measure antibody binding and conformation changes in the protein. The work demonstrates a capability for comprehensive protein analysis and precision protein biomarker detection at the single molecule level.

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Analysis of distribution and severity of inflammation in patients with osteoarthitis compared to rheumatoid arthritis by ICG-enhanced fluorescence optical imaging and musculoskeletal ultrasound: a pilot study

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2015-207345 ◽

2015 ◽

Vol 75 (3) ◽

pp. 566-570 ◽

Cited By ~ 26

Author(s):

A-M Glimm ◽

S G Werner ◽

G R Burmester ◽

M Backhaus ◽

S Ohrndorf

Keyword(s):

Rheumatoid Arthritis ◽

Optical Imaging ◽

Joint Inflammation ◽

Musculoskeletal Ultrasound ◽

Imaging Method ◽

Hand Osteoarthritis ◽

Dominant Hand ◽

Fluorescence Optical Imaging ◽

Inflammatory Status ◽

Inflammatory Changes

BackgroundIn rheumatoid arthritis (RA), hand synovitis appears especially in wrist, metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. In hand osteoarthritis (OA), potential inflammatory changes are mainly present in PIP and distal interphalangeal (DIP) joints. Joint inflammation can be visualised by fluorescence optical imaging (FOI) and musculoskeletal ultrasound (US).ObjectiveComparison of the amount and distribution of inflammatory signs in wrist and finger joints of the clinically dominant hand in patients with OA and RA by FOI and gray-scale (GSUS) and power Doppler US (PDUS).MethodsFOI and GSUS/PDUS were performed in 1.170 joints (wrists, MCP, PIP, DIP) in 90 patients (67 RA, 23 OA). Joint inflammation was graded by a semiquantitative score (0–3) for each imaging method.ResultsGSUS/PDUS showed wrist and MCP joints mostly affected in RA. DIP joints were graded higher in OA. In FOI, RA and OA featured inflammatory changes in the respective joint groups depending on the phase of fluorescence dye flooding.ConclusionsUS and FOI detected inflammation in both RA and OA highlighting the inflammatory component in the course of OA. The different inflammatory patterns and various shapes of fluorescence enhancement in FOI may offer opportunities to distinguish and determine the inflammatory status in both diseases.

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