Forward-Looking Ultrasound Wearable Scanner System for Estimation of Urinary Bladder Volume

Accurate measurement of bladder volume is an important tool for evaluating bladder function. In this study, we propose a wearable bladder scanner system that can continuously measure bladder volume in daily life for urinary patients who need urodynamic studies. The system consisted of a 2-D array, which included integrated forward-looking piezoelectric transducers with thin substrates. This study aims to estimate the volume of the bladder using a small number of piezoelectric transducers. A least-squares method was implemented to optimize an ellipsoid in a quadratic surface equation for bladder volume estimation. Ex-vivo experiments of a pig bladder were conducted to validate the proposed system. This work presents the potential of the approach for wearable bladder monitoring, which has similar measurement accuracy compared to the commercial bladder imaging system. The wearable bladder scanner can be improved further as electronic voiding diaries by adding a few more features to the current function.

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Simple calculation using anatomical features on pre-treatment verification CT for bladder volume estimation during radiation therapy for rectal cancer

BMC Cancer ◽

10.1186/s12885-020-07405-z ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Nalee Kim ◽

Hong In Yoon ◽

Jin Sung Kim ◽

Woong Sub Koom ◽

Jee Suk Chang ◽

...

Keyword(s):

Radiation Therapy ◽

Cone Beam Ct ◽

Ct Images ◽

Volume Estimation ◽

Bladder Volume ◽

Cone Beam ◽

Anatomical Features ◽

Treatment Verification ◽

Pre Treatment ◽

Bladder Scanner

Abstract Background Despite detailed instruction for full bladder, patients are unable to maintain consistent bladder filling during a 5-week pelvic radiation therapy (RT) course. We investigated the best bladder volume estimation procedure for verifying consistent bladder volume. Methods We reviewed 462 patients who underwent pelvic RT. Biofeedback using a bladder scanner was conducted before simulation and during treatment. Exact bladder volume was calculated by bladder inner wall contour based on CT images (Vctsim). Bladder volume was estimated either by bladder scanner (Vscan) or anatomical features from the presacral promontory to the bladder base and dome in the sagittal plane of CT (Vratio). The feasibility of Vratio was validated using daily megavoltage or kV cone-beam CT before treatment. Results Mean Vctsim was 335.6 ± 147.5 cc. Despite a positive correlation between Vctsim and Vscan (R2 = 0.278) and between Vctsim and Vratio (R2 = 0.424), Vratio yielded more consistent results than Vscan, with a mean percentage error of 26.3 (SD 19.6, p < 0.001). The correlation between Vratio and Vctsim was stronger than that between Vscan and Vctsim (Z-score: − 7.782, p < 0.001). An accuracy of Vratio was consistent in megavoltage or kV cone-beam CT during treatment. In a representative case, we can dichotomize for clinical scenarios with or without bowel displacement, using a ratio of 0.8 resulting in significant changes in bowel volume exposed to low radiation doses. Conclusions Bladder volume estimation using personalized anatomical features based on pre-treatment verification CT images was useful and more accurate than physician-dependent bladder scanners. Trial registration Retrospectively registered.

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Morpho-molecular ex vivo detection and grading of non-muscle-invasive bladder cancer using forward imaging probe based multimodal optical coherence tomography and Raman spectroscopy

The Analyst ◽

10.1039/c9an01911a ◽

2020 ◽

Vol 145 (4) ◽

pp. 1445-1456 ◽

Cited By ~ 1

Author(s):

Fabian Placzek ◽

Eliana Cordero Bautista ◽

Simon Kretschmer ◽

Lara M. Wurster ◽

Florian Knorr ◽

...

Keyword(s):

Raman Spectroscopy ◽

Optical Coherence Tomography ◽

Imaging System ◽

Ex Vivo ◽

Large Field ◽

Optical Coherence ◽

Fiber Optic Probe ◽

Optic Probe ◽

Muscle Invasive

Characterization of bladder biopsies, using a combined fiber optic probe-based optical coherence tomography and Raman spectroscopy imaging system that allows a large field-of-view imaging and detection and grading of cancerous bladder lesions.

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Performance of a novel protease-activated fluorescent imaging system for intraoperative detection of residual breast cancer during breast conserving surgery

Breast Cancer Research and Treatment ◽

10.1007/s10549-021-06106-w ◽

2021 ◽

Vol 187 (1) ◽

pp. 145-153

Author(s):

Conor R. Lanahan ◽

Bridget N. Kelly ◽

Michele A. Gadd ◽

Michelle C. Specht ◽

Carson L. Brown ◽

...

Keyword(s):

Breast Cancer ◽

Real Time ◽

Imaging System ◽

Ex Vivo ◽

Menopausal Status ◽

Fluorescent Imaging ◽

Cancer Subtypes ◽

Surgical Workflow ◽

Tumor Types

Abstract Purpose Safe breast cancer lumpectomies require microscopically clear margins. Real-time margin assessment options are limited, and 20–40% of lumpectomies have positive margins requiring re-excision. The LUM Imaging System previously showed excellent sensitivity and specificity for tumor detection during lumpectomy surgery. We explored its impact on surgical workflow and performance across patient and tumor types. Methods We performed IRB-approved, prospective, non-randomized studies in breast cancer lumpectomy procedures. The LUM Imaging System uses LUM015, a protease-activated fluorescent imaging agent that identifies residual tumor in the surgical cavity walls. Fluorescent cavity images were collected in real-time and analyzed using system software. Results Cavity and specimen images were obtained in 55 patients injected with LUM015 at 0.5 or 1.0 mg/kg and in 5 patients who did not receive LUM015. All tumor types were distinguished from normal tissue, with mean tumor:normal (T:N) signal ratios of 3.81–5.69. T:N ratios were 4.45 in non-dense and 4.00 in dense breasts (p = 0.59) and 3.52 in premenopausal and 4.59 in postmenopausal women (p = 0.19). Histopathology and tumor receptor testing were not affected by LUM015. Falsely positive readings were more likely when tumor was present < 2 mm from the adjacent specimen margin. LUM015 signal was stable in vivo at least 6.5 h post injection, and ex vivo at least 4 h post excision. Conclusions Intraoperative use of the LUM Imaging System detected all breast cancer subtypes with robust performance independent of menopausal status and breast density. There was no significant impact on histopathology or receptor evaluation.

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A Tumbling Magnetic Microrobot System for Biomedical Applications

Micromachines ◽

10.3390/mi11090861 ◽

2020 ◽

Vol 11 (9) ◽

pp. 861

Author(s):

Elizabeth E. Niedert ◽

Chenghao Bi ◽

Georges Adam ◽

Elly Lambert ◽

Luis Solorio ◽

...

Keyword(s):

Ultrasound Imaging ◽

Biomedical Applications ◽

Imaging System ◽

Ex Vivo ◽

Negative Control ◽

Circular Path ◽

Rotational Axis ◽

Significant Difference

A microrobot system comprising an untethered tumbling magnetic microrobot, a two-degree-of-freedom rotating permanent magnet, and an ultrasound imaging system has been developed for in vitro and in vivo biomedical applications. The microrobot tumbles end-over-end in a net forward motion due to applied magnetic torque from the rotating magnet. By turning the rotational axis of the magnet, two-dimensional directional control is possible and the microrobot was steered along various trajectories, including a circular path and P-shaped path. The microrobot is capable of moving over the unstructured terrain within a murine colon in in vitro, in situ, and in vivo conditions, as well as a porcine colon in ex vivo conditions. High-frequency ultrasound imaging allows for real-time determination of the microrobot’s position while it is optically occluded by animal tissue. When coated with a fluorescein payload, the microrobot was shown to release the majority of the payload over a 1-h time period in phosphate-buffered saline. Cytotoxicity tests demonstrated that the microrobot’s constituent materials, SU-8 and polydimethylsiloxane (PDMS), did not show a statistically significant difference in toxicity to murine fibroblasts from the negative control, even when the materials were doped with magnetic neodymium microparticles. The microrobot system’s capabilities make it promising for targeted drug delivery and other in vivo biomedical applications.

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Numerical Analysis of a Flexible Dual Loop Coil and its Experimental Validation for pre-Clinical Magnetic Resonance Imaging of Rodents at 7 T

Measurement Science Review ◽

10.1515/msr-2016-0037 ◽

2016 ◽

Vol 16 (6) ◽

pp. 294-299 ◽

Cited By ~ 1

Author(s):

S. Solis-Najera ◽

F. Vazquez ◽

R. Hernandez ◽

O. Marrufo ◽

A.O. Rodriguez

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Imaging System ◽

Ex Vivo ◽

Small Animal ◽

Magnetic Resonance Imaging System ◽

External Diameter ◽

Rf Coil ◽

Resonance Imaging ◽

Clinical Magnetic Resonance Imaging

Abstract A surface radio frequency coil was developed for small animal image acquisition in a pre-clinical magnetic resonance imaging system at 7 T. A flexible coil composed of two circular loops was developed to closely cover the object to be imaged. Electromagnetic numerical simulations were performed to evaluate its performance before the coil construction. An analytical expression of the mutual inductance for the two circular loops as a function of the separation between them was derived and used to validate the simulations. The RF coil is composed of two circular loops with a 5 cm external diameter and was tuned to 300 MHz and 50 Ohms matched. The angle between the loops was varied and the Q factor was obtained from the S11 simulations for each angle. B1 homogeneity was also evaluated using the electromagnetic simulations. The coil prototype was designed and built considering the numerical simulation results. To show the feasibility of the coil and its performance, saline-solution phantom images were acquired. A correlation of the simulations and imaging experimental results was conducted showing a concordance of 0.88 for the B1 field. The best coil performance was obtained at the 90° aperture angle. A more realistic phantom was also built using a formaldehyde-fixed rat phantom for ex vivo imaging experiments. All images showed a good image quality revealing clearly defined anatomical details of an ex vivo rat.

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Synthetic Aperture Imaging Using High-Frequency Convex Array for Ophthalmic Ultrasound Applications

Sensors ◽

10.3390/s21072275 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2275

Author(s):

Hae Gyun Lim ◽

Hyung Ham Kim ◽

Changhan Yoon

Keyword(s):

Image Quality ◽

Penetration Depth ◽

Spatial Resolution ◽

High Frequency ◽

Imaging System ◽

Ex Vivo ◽

Synthetic Aperture ◽

Single Element ◽

High Frequency Ultrasound ◽

Synthetic Aperture Imaging

High-frequency ultrasound (HFUS) imaging has emerged as an essential tool for pre-clinical studies and clinical applications such as ophthalmic and dermatologic imaging. HFUS imaging systems based on array transducers capable of dynamic receive focusing have considerably improved the image quality in terms of spatial resolution and signal-to-noise ratio (SNR) compared to those by the single-element transducer-based one. However, the array system still suffers from low spatial resolution and SNR in out-of-focus regions, resulting in a blurred image and a limited penetration depth. In this paper, we present synthetic aperture imaging with a virtual source (SA-VS) for an ophthalmic application using a high-frequency convex array transducer. The performances of the SA-VS were evaluated with phantom and ex vivo experiments in comparison with the conventional dynamic receive focusing method. Pre-beamformed radio-frequency (RF) data from phantoms and excised bovine eye were acquired using a custom-built 64-channel imaging system. In the phantom experiments, the SA-VS method showed improved lateral resolution (>10%) and sidelobe level (>4.4 dB) compared to those by the conventional method. The SNR was also improved, resulting in an increased penetration depth: 16 mm and 23 mm for the conventional and SA-VS methods, respectively. Ex vivo images with the SA-VS showed improved image quality at the entire depth and visualized structures that were obscured by noise in conventional imaging.

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Mesenchymal stem cells accelerated growth and metastasis of neuroblastoma and preferentially homed towards both primary and metastatic loci in orthotopic neuroblastoma model

BMC Cancer ◽

10.1186/s12885-021-08090-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jiao-Le Yu ◽

Shing Chan ◽

Marcus Kwong-Lam Fung ◽

Godfrey Chi-Fung Chan

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Primary Tumor ◽

Imaging System ◽

Ex Vivo ◽

Tumor Formation ◽

Human Neuroblastoma Cell ◽

Fluorescence Signal ◽

Human Neuroblastoma

Abstract Background Majority of neuroblastoma patients develop metastatic disease at diagnosis and their prognosis is poor with current therapeutic approach. Major challenges are how to tackle the mechanisms responsible for tumorigenesis and metastasis. Human mesenchymal stem cells (hMSCs) may be actively involved in the constitution of cancer microenvironment. Methods An orthotopic neuroblastoma murine model was utilized to mimic the clinical scenario. Human neuroblastoma cell line SK-N-LP was transfected with luciferase gene, which were inoculated with/without hMSCs into the adrenal area of SCID-beige mice. The growth and metastasis of neuroblastoma was observed by using Xenogen IVIS 100 in vivo imaging and evaluating gross tumors ex vivo. The homing of hMSCs towards tumor was analyzed by tracing fluorescence signal tagged on hMSCs using CRI Maestro™ imaging system. Results hMSCs mixed with neuroblastoma cells significantly accelerated tumor growth and apparently enhanced metastasis of neuroblastoma in vivo. hMSCs could be recruited by primary tumor and also become part of the tumor microenvironment in the metastatic lesion. The metastatic potential was consistently reduced in lung and tumor when hMSCs were pre-treated with stromal cell derived factor-1 (SDF-1) blocker, AMD3100, suggesting that the SDF-1/CXCR4 axis was one of the prime movers in the metastatic process. Conclusions hMSCs accelerated and facilitated tumor formation, growth and metastasis. Furthermore, the homing propensity of hMSCs towards both primary tumor and metastatic loci can also provide new therapeutic insights in utilizing bio-engineered hMSCs as vehicles for targeted anti-cancer therapy.

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An Egg Volume Measurement System Based on the Microsoft Kinect

Sensors ◽

10.3390/s18082454 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2454 ◽

Cited By ~ 11

Author(s):

Ting Chan ◽

Derek Lichti ◽

Adam Jahraus ◽

Hooman Esfandiari ◽

Herve Lahamy ◽

...

Keyword(s):

Least Squares ◽

Point Cloud ◽

Least Squares Method ◽

Point Clouds ◽

Volume Estimation ◽

Microsoft Kinect ◽

Estimation Accuracy ◽

Shape Parameters ◽

Post Processing ◽

Egg Volume

Measuring the volume of bird eggs is a very important task for the poultry industry and ornithological research due to the high revenue generated by the industry. In this paper, we describe a prototype of a new metrological system comprising a 3D range camera, Microsoft Kinect (Version 2) and a point cloud post-processing algorithm for the estimation of the egg volume. The system calculates the egg volume directly from the egg shape parameters estimated from the least-squares method in which the point clouds of eggs captured by the Kinect are fitted to novel geometric models of an egg in a 3D space. Using the models, the shape parameters of an egg are estimated along with the egg’s position and orientation simultaneously under the least-squares criterion. Four sets of experiments were performed to verify the functionality and the performance of the system, while volumes estimated from the conventional water displacement method and the point cloud captured by a survey-grade laser scanner serve as references. The results suggest that the method is straightforward, feasible and reliable with an average egg volume estimation accuracy 93.3% when compared to the reference volumes. As a prototype, the software part of the system was implemented in a post-processing mode. However, as the proposed processing techniques is computationally efficient, the prototype can be readily transformed into a real-time egg volume system.

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Proof of concept of a multimodal intravital molecular imaging system for tumour transpathology investigation

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-021-05574-y ◽

2021 ◽

Author(s):

Zhen Liu ◽

Tao Cheng ◽

Stephan Düwel ◽

Ziying Jian ◽

Geoffrey J. Topping ◽

...

Keyword(s):

Molecular Imaging ◽

Imaging System ◽

Ex Vivo ◽

Fiducial Markers ◽

Proof Of Concept ◽

Registration Accuracy ◽

Microscopic Imaging ◽

Window Chamber

Abstract Background Transpathology highlights the interpretation of the underlying physiology behind molecular imaging. However, it remains challenging due to the discrepancies between in vivo and in vitro measurements and difficulties of precise co-registration between trans-scaled images. This study aims to develop a multimodal intravital molecular imaging (MIMI) system as a tool for in vivo tumour transpathology investigation. Methods The proposed MIMI system integrates high-resolution positron imaging, magnetic resonance imaging (MRI) and microscopic imaging on a dorsal skin window chamber on an athymic nude rat. The window chamber frame was designed to be compatible with multimodal imaging and its fiducial markers were customized for precise physical alignment among modalities. The co-registration accuracy was evaluated based on phantoms with thin catheters. For proof of concept, tumour models of the human colorectal adenocarcinoma cell line HT-29 were imaged. The tissue within the window chamber was sectioned, fixed and haematoxylin–eosin (HE) stained for comparison with multimodal in vivo imaging. Results The final MIMI system had a maximum field of view (FOV) of 18 mm × 18 mm. Using the fiducial markers and the tubing phantom, the co-registration errors are 0.18 ± 0.27 mm between MRI and positron imaging, 0.19 ± 0.22 mm between positron imaging and microscopic imaging and 0.15 ± 0.27 mm between MRI and microscopic imaging. A pilot test demonstrated that the MIMI system provides an integrative visualization of the tumour anatomy, vasculatures and metabolism of the in vivo tumour microenvironment, which was consistent with ex vivo pathology. Conclusions The established multimodal intravital imaging system provided a co-registered in vivo platform for trans-scale and transparent investigation of the underlying pathology behind imaging, which has the potential to enhance the translation of molecular imaging.

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