Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
24,837
result(s) for
"Confocal"
Sort by:
Machine Learning Based Prediction of Squamous Cell Carcinoma in Ex Vivo Confocal Laser Scanning Microscopy
by
Daniela Hartmann
,
Cristel Ruini
,
Benjamin Kendziora
in
Algorithms
,
Artificial intelligence
,
Big Data
2021
Image classification with convolutional neural networks (CNN) offers an unprecedented opportunity to medical imaging. Regulatory agencies in the USA and Europe have already cleared numerous deep learning/machine learning based medical devices and algorithms. While the field of radiology is on the forefront of artificial intelligence (AI) revolution, conventional pathology, which commonly relies on examination of tissue samples on a glass slide, is falling behind in leveraging this technology. On the other hand, ex vivo confocal laser scanning microscopy (ex vivo CLSM), owing to its digital workflow features, has a high potential to benefit from integrating AI tools into the assessment and decision-making process. Aim of this work was to explore a preliminary application of CNN in digitally stained ex vivo CLSM images of cutaneous squamous cell carcinoma (cSCC) for automated detection of tumor tissue. Thirty-four freshly excised tissue samples were prospectively collected and examined immediately after resection. After the histologically confirmed ex vivo CLSM diagnosis, the tumor tissue was annotated for segmentation by experts, in order to train the MobileNet CNN. The model was then trained and evaluated using cross validation. The overall sensitivity and specificity of the deep neural network for detecting cSCC and tumor free areas on ex vivo CLSM slides compared to expert evaluation were 0.76 and 0.91, respectively. The area under the ROC curve was equal to 0.90 and the area under the precision-recall curve was 0.85. The results demonstrate a high potential of deep learning models to detect cSCC regions on digitally stained ex vivo CLSM slides and to distinguish them from tumor-free skin.
Journal Article
Line-Field Confocal Optical Coherence Tomography: A New Tool for the Differentiation between Nevi and Melanomas?
by
Cristel Ruini
,
Maria Katharina Elisabeth Perwein
,
Elke Christina Sattler
in
Cameras
,
Confocal microscopy
,
ddc:610
2022
Until now, the clinical differentiation between a nevus and a melanoma is still challenging in some cases. Line-field confocal optical coherence tomography (LC-OCT) is a new tool with the aim to change that. The aim of the study was to evaluate LC-OCT for the discrimination between nevi and melanomas. A total of 84 melanocytic lesions were examined with LC-OCT and 36 were also imaged with RCM. The observers recorded the diagnoses, and the presence or absence of the 18 most common imaging parameters for melanocytic lesions, nevi, and melanomas in the LC-OCT images. Their confidence in diagnosis and the image quality of LC-OCT and RCM were evaluated. The most useful criteria, the sensitivity and specificity of LC-OCT vs. RCM vs. histology, to differentiate a (dysplastic) nevus from a melanoma were analyzed. Good image quality correlated with better diagnostic performance (Spearman correlation: 0.4). LC-OCT had a 93% sensitivity and 100% specificity compared to RCM (93% sensitivity, 95% specificity) for diagnosing a melanoma (vs. all types of nevi). No difference in performance between RCM and LC-OCT was observed (McNemar’s p value = 1). Both devices falsely diagnosed dysplastic nevi as non-dysplastic (43% sensitivity for dysplastic nevus diagnosis). The most significant criteria for diagnosing a melanoma with LC-OCT were irregular honeycombed patterns (92% occurrence rate; 31.7 odds ratio (OR)), the presence of pagetoid spread (89% occurrence rate; 23.6 OR) and the absence of dermal nests (23% occurrence rate, 0.02 OR). In conclusion LC-OCT is useful for the discrimination between melanomas and nevi.
Journal Article
Confocal Microscopy for Diagnosis and Management of Cutaneous Malignancies: Clinical Impacts and Innovation
by
Atak, Mehmet Fatih
,
Navarrete-Dechent, Cristian
,
Rajadhyaksha, Milind
in
Accuracy
,
Biopsy
,
Care and treatment
2023
Cutaneous malignancies are common malignancies worldwide, with rising incidence. Most skin cancers, including melanoma, can be cured if diagnosed correctly at an early stage. Thus, millions of biopsies are performed annually, posing a major economic burden. Non-invasive skin imaging techniques can aid in early diagnosis and save unnecessary benign biopsies. In this review article, we will discuss in vivo and ex vivo confocal microscopy (CM) techniques that are currently being utilized in dermatology clinics for skin cancer diagnosis. We will discuss their current applications and clinical impact. Additionally, we will provide a comprehensive review of the advances in the field of CM, including multi-modal approaches, the integration of fluorescent targeted dyes, and the role of artificial intelligence for improved diagnosis and management.
Journal Article
Role of VivaScope 2500 ex vivo confocal microscopy in skin pathology: Advantages, limitations, and future prospects
by
Khan, Samavia
,
Razi, Shazli
,
Oh, Kei Shing
in
Acids
,
Basal Cell Carcinoma - pathology
,
Cancer
2023
Background Vivascope 2500 ex vivo confocal microscopy (EVCM) is an emerging optical imaging device that allows nuclear level resolution of freshly excised tissues. EVCM provides, rapid real‐time pathological examination in many subspecialties of pathology including skin, prostate, breast, liver, etc. In contrast to traditional time‐consuming frozen sectioning and histological analysis. Aims To evaluate the current state of EVCM utilization. Materials and Methods This study highlights the advantages, limitations, and prospects of EVCM in skin pathology. Results Our findings demonstrate that EVCM is a promising adjunctive tool to assess margins in Mohs surgery and to provide rapid, accurate diagnosis of cutaneous tumors, infectious and inflammatory diseases. Conclusion EVCM is a revolutionary device that can be used as an adjunct to paraffin‐fixed, hematoxylin and eosin‐stained slides and frozen sectioning. Additional refinements are required before EVCM can be used as an alternative to frozen sectioning or traditional tissue processing.
Journal Article
Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities
2017
To assess the effect of applying a protocol for image selection and the number of images required for adequate quantification of corneal nerve pathology using in vivo corneal confocal microscopy (IVCCM).
IVCCM was performed in 35 participants by a single examiner. For each participant, 4 observers used a standardized protocol to select 6 central corneal nerve images to assess the inter-observer variability. Furthermore, images were selected by a single observer on two occasions to assess intra-observer variability and the effect of sample size was assessed by comparing 6 with 12 images. Corneal nerve fiber density (CNFD), branch density (CNBD) and length (CNFL) were quantified using fully automated software. The data were compared using the intra class correlation coefficient (ICC) and Bland-Altman agreement plots for all experiments.
The ICC values for CNFD, CNBD and CNFL were 0.93 (P<0.0001), 0.96 (P<0.0001) and 0.95 (P<0.0001) for inter-observer variability and 0.95 (P<0.0001), 0.97 (P<0.001) and 0.97 (P<0.0001) for intra-observer variability. For sample size variability, ICC values were 0.94 (P<0.0001), 0.95 (P<0.0001), and 0.96 (P<0.0001) for CNFD, CNBD and CNFL. Bland-Altman plots showed excellent agreement for all parameters.
This study shows that implementing a standardized protocol to select IVCCM images results in high intra and inter-observer reproducibility for all corneal nerve parameters and 6 images are adequate for analysis. IVCCM could therefore be deployed in large multicenter clinical trials with confidence.
Journal Article
Multiview confocal super-resolution microscopy
2021
Confocal microscopy
1
remains a major workhorse in biomedical optical microscopy owing to its reliability and flexibility in imaging various samples, but suffers from substantial point spread function anisotropy, diffraction-limited resolution, depth-dependent degradation in scattering samples and volumetric bleaching
2
. Here we address these problems, enhancing confocal microscopy performance from the sub-micrometre to millimetre spatial scale and the millisecond to hour temporal scale, improving both lateral and axial resolution more than twofold while simultaneously reducing phototoxicity. We achieve these gains using an integrated, four-pronged approach: (1) developing compact line scanners that enable sensitive, rapid, diffraction-limited imaging over large areas; (2) combining line-scanning with multiview imaging, developing reconstruction algorithms that improve resolution isotropy and recover signal otherwise lost to scattering; (3) adapting techniques from structured illumination microscopy, achieving super-resolution imaging in densely labelled, thick samples; (4) synergizing deep learning with these advances, further improving imaging speed, resolution and duration. We demonstrate these capabilities on more than 20 distinct fixed and live samples, including protein distributions in single cells; nuclei and developing neurons in
Caenorhabditis elegans
embryos, larvae and adults; myoblasts in imaginal disks of
Drosophila
wings; and mouse renal, oesophageal, cardiac and brain tissues.
A combination of multiview imaging, structured illumination, reconstruction algorithms and deep-learning predictions realizes spatial- and temporal-resolution improvements in fluorescence microscopy to produce super-resolution images from diffraction-limited input images.
Journal Article
An artificial intelligence-based deep learning algorithm for the diagnosis of diabetic neuropathy using corneal confocal microscopy: a development and validation study
by
Lim, Jonathan
,
Williams, Bryan M
,
Ma Baikai
in
Algorithms
,
Artificial intelligence
,
Automation
2020
Aims/hypothesisCorneal confocal microscopy is a rapid non-invasive ophthalmic imaging technique that identifies peripheral and central neurodegenerative disease. Quantification of corneal sub-basal nerve plexus morphology, however, requires either time-consuming manual annotation or a less-sensitive automated image analysis approach. We aimed to develop and validate an artificial intelligence-based, deep learning algorithm for the quantification of nerve fibre properties relevant to the diagnosis of diabetic neuropathy and to compare it with a validated automated analysis program, ACCMetrics.MethodsOur deep learning algorithm, which employs a convolutional neural network with data augmentation, was developed for the automated quantification of the corneal sub-basal nerve plexus for the diagnosis of diabetic neuropathy. The algorithm was trained using a high-end graphics processor unit on 1698 corneal confocal microscopy images; for external validation, it was further tested on 2137 images. The algorithm was developed to identify total nerve fibre length, branch points, tail points, number and length of nerve segments, and fractal numbers. Sensitivity analyses were undertaken to determine the AUC for ACCMetrics and our algorithm for the diagnosis of diabetic neuropathy.ResultsThe intraclass correlation coefficients for our algorithm were superior to those for ACCMetrics for total corneal nerve fibre length (0.933 vs 0.825), mean length per segment (0.656 vs 0.325), number of branch points (0.891 vs 0.570), number of tail points (0.623 vs 0.257), number of nerve segments (0.878 vs 0.504) and fractals (0.927 vs 0.758). In addition, our proposed algorithm achieved an AUC of 0.83, specificity of 0.87 and sensitivity of 0.68 for the classification of participants without (n = 90) and with (n = 132) neuropathy (defined by the Toronto criteria).Conclusions/interpretationThese results demonstrated that our deep learning algorithm provides rapid and excellent localisation performance for the quantification of corneal nerve biomarkers. This model has potential for adoption into clinical screening programmes for diabetic neuropathy.Data availabilityThe publicly shared cornea nerve dataset (dataset 1) is available at http://bioimlab.dei.unipd.it/Corneal%20Nerve%20Tortuosity%20Data%20Set.htm and http://bioimlab.dei.unipd.it/Corneal%20Nerve%20Data%20Set.htm.
Journal Article
Classification and Segmentation of Nanoparticle Diffusion Trajectories in Cellular Micro Environments
by
Wagner, Thorsten
,
Kroll, Alexandra
,
Lipinski, Hans-Gerd
in
Cell Biology
,
Cells (Biology)
,
Classification
2017
Darkfield and confocal laser scanning microscopy both allow for a simultaneous observation of live cells and single nanoparticles. Accordingly, a characterization of nanoparticle uptake and intracellular mobility appears possible within living cells. Single particle tracking allows to measure the size of a diffusing particle close to a cell. However, within the more complex system of a cell's cytoplasm normal, confined or anomalous diffusion together with directed motion may occur. In this work we present a method to automatically classify and segment single trajectories into their respective motion types. Single trajectories were found to contain more than one motion type. We have trained a random forest with 9 different features. The average error over all motion types for synthetic trajectories was 7.2%. The software was successfully applied to trajectories of positive controls for normal- and constrained diffusion. Trajectories captured by nanoparticle tracking analysis served as positive control for normal diffusion. Nanoparticles inserted into a diblock copolymer membrane was used to generate constrained diffusion. Finally we segmented trajectories of diffusing (nano-)particles in V79 cells captured with both darkfield- and confocal laser scanning microscopy. The software called \"TraJClassifier\" is freely available as ImageJ/Fiji plugin via https://git.io/v6uz2.
Journal Article
Mapping mechanical properties of biological materials via an add-on Brillouin module to confocal microscopes
2021
Several techniques have been developed over the past few decades to assess the mechanical properties of biological samples, which has fueled a rapid growth in the fields of biophysics, bioengineering, and mechanobiology. In this context, Brillouin optical spectroscopy has long been known as an intriguing modality for noncontact material characterization. However, limited by speed and sample damage, it had not translated into a viable imaging modality for biomedically relevant materials. Recently, based on a novel spectroscopy strategy that substantially improves the speed of Brillouin measurement, confocal Brillouin microscopy has emerged as a unique complementary tool to traditional methods as it allows noncontact, nonperturbative, label-free measurements of material mechanical properties. The feasibility and potential of this innovative technique at both the cell and tissue level have been extensively demonstrated over the past decade. As Brillouin technology is rapidly recognized, a standard approach for building and operating Brillouin microscopes is required to facilitate the widespread adoption of this technology. In this protocol, we aim to establish a robust approach for instrumentation, and data acquisition and analysis. By carefully following this protocol, we expect that a Brillouin instrument can be built in 5–9 days by a person with basic optics knowledge and alignment experience; the data acquisition as well as postprocessing can be accomplished within 2–8 h.
A protocol for implementing Brillouin microscopy to study biological materials. The procedure contains instructions for integrating an add-on Brillouin module with an existing confocal microscope as well as for its calibration and use in data collection and processing.
Journal Article
The Relationship between the Bcl-2/Bax Proteins and the Mitochondria-Mediated Apoptosis Pathway in the Differentiation of Adipose-Derived Stromal Cells into Neurons
by
Zhang, Lili
,
Zhu, Xuhong
,
Wang, Quanquan
in
Adipose Tissue - cytology
,
Apoptosis
,
BAX protein
2016
Our objective is to study the relationship between the regulatory proteins Bcl-2/Bax and mitochondria-mediated apoptosis during the differentiation of adipose-derived stromal cells (ADSCs) into neurons. Immunocytochemistry and western blotting showed that the cells weakly expressed neuron-specific enolase (NSE) in the non-induced group and expressed NSE more strongly in the groups induced for 1 h, 3 h, 5 h and 8 h. NSE expression peaked at 5 h (P < 0.05), although there was no significant difference between 5 and 8 h (P > 0.05). Bcl-2 expression gradually decreased over time in the non-induced group (P < 0.05). However, Bax, caspase-9, Cyt-c and caspase-3 expression gradually increased and peaked at 8 h (P < 0.05). Transmission electron microscopy revealed karyopyknosis, chromatin edge setting, mitochondria swelling and cavitation in cells at 5 h, and the mitochondrial membrane potential decreased over time, as demonstrated by laser scanning confocal microscopy. After a 5 h induction, cells differentiated into typical neurons and expressed Bcl-2, which inhibited apoptosis. Bax showed a strong apoptosis-promoting capacity, leading to changes in the mitochondrial membrane potential and structure, and then triggered the caspase-independent apoptotic response through the mitochondrial pathway. At the same time, Cyt-c was directly or indirectly released from the mitochondria to the cytoplasm to trigger the caspase-dependent apoptotic response through the mitochondrial pathway. Therefore, Bcl-2/Bax play an important role in regulating caspase-dependent and caspase-independent apoptosis mediated by the mitochondrial pathway during the differentiation of ADSCs into neurons.
Journal Article