V tomto sdělení chceme prezentovat přínos MRI/TRUS softwarové fúze při cílené biopsii prostaty a demonstrovat naše praktické zkušenosti se softwarovou fúzí za dvouleté období. Všichni pacienti s PSA < 20 ng/ml, měli provedeno triparametrické MR vyšetření prostaty, byli klasifikování systémem PI RADS v 2. Fúze byla prováděna s ultrazvukovým přístrojem BK Medical Flex Focus 400 s transrektální sondou 8808e – 10 Hz. Prezentujeme soubor vyšetřovaných pacientů včetně jejich histologických výsledků, kde prokazujeme efekt cílené biopsie Ta u všech provedených biopsií verifikovala karcinom prostaty u 48,25 % pacientů, systematická biopsie verifikovala karcinom prostaty u 35,46 % pacientů. U rebiopsií prostaty cílená biopsie verifikovala karcinom prostaty u 49,21 % pacientů, systematická biopsie verifikovala karcinom prostaty u 29,68 % pacientů. Naše práce potvrdila efekt cílené biopsie prostaty i u primobiopsií, kdy jsme prokázali, že bychom v našem souboru nezachytili karcinom prostaty u 9,09 % pacientů, pokud bychom cílenou biopsii neprovedli. Naše výsledky se shodují s doporučenými postupy Evropské urologické společnosti (EAU) z roku 2019.
We would like to present the benefits of the MRI/TRUS fusion software targeted at prostate biopsies and demonstrate our practical experience with the fusion software over the course of two years. All patients with PSA < 20 ng/ml underwent three parametric prostate MRI, they were classified by the PI RADS v 2 systém. The fusion was carried out with the ultrasound device BK Medical Flex Focus 400 with transrectal probe 8808 – 10Hz. We present a group of examined patients and their histological results, where we demonstrate the effect of the targeted biopsy. For all the biopsies performed, it verified prostate carcinoma in 48 25% of patients, and systematic biopsy verified prostate carcinoma in 35 46% of patients. For rebiopsy of the prostate, the targeted biopsy verified prostate carcinoma in 49 21% of the patients, and systematic biopsy verified prostate carcinoma in 29 68% of patients. Our work confirmed the effect of targeted prostate biopsy for primobiopsy, where we have shown that in our group prostate carcinoma in 9 09% of patients would have been missed if we had not performed targeted biopsy. Our results are consistent with the 2019 recommendations of the European Association of Urology (EAU).
Recently, the demand for hybrid PET/MRI imaging techniques has increased significantly, which has sparked the investigation into new ways to simultaneously track multiple molecular targets and improve the localization and expression of biochemical markers. Multimodal imaging probes have recently emerged as powerful tools for improving the detection sensitivity and accuracy-both important factors in disease diagnosis and treatment; however, only a limited number of bimodal probes have been investigated in preclinical models. Herein, we briefly describe the strengths and limitations of PET and MRI modalities and highlight the need for the development of multimodal molecularly-targeted agents. We have tried to thoroughly summarize data on bimodal probes available on PubMed. Emphasis was placed on their design, safety profiles, pharmacokinetics, and clearance properties. The challenges in PET/MR probe development using a number of illustrative examples are also discussed, along with future research directions for these novel conjugates.
- MeSH
- Magnetic Resonance Imaging * MeSH
- Multimodal Imaging MeSH
- Positron-Emission Tomography * MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
In clinical practice the imaging of bone tissue is based almost exclusively on x-ray or radiochemical methods. Alternative methods, such as MRI and optical imaging, can provide not only anatomical, but also physiological information, due to their ability to reflect the properties of body fluids (temperature, pH and concentration of ions). In this article we review bone targeting probes for MRI and fluorescence imaging. As bone targeting is mainly associated with phosphonate and bisphosphonate derivatives, we also focus on their sorption behavior. Also discussed in detail is the limitation of using bone-targeting probes for MRI and optical imaging mainly due to their long-time retention in bone tissue and the low permeability of tissues for light.
- MeSH
- Fluorescent Dyes chemistry metabolism MeSH
- Bone and Bones cytology metabolism MeSH
- Metals chemistry MeSH
- Humans MeSH
- Magnetic Resonance Imaging methods MeSH
- Molecular Structure MeSH
- Molecular Imaging methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
Over the last few years, the development and relevance of 19F magnetic resonance imaging (MRI) for use in clinical practice has emerged. MRI using fluorinated probes enables the achievement of a specific signal with high contrast in MRI images. However, to ensure sufficient sensitivity of 19F MRI, fluorine probes with a high content of chemically equivalent fluorine atoms are required. The majority of 19F MRI agents are perfluorocarbon emulsions, which have a broad range of applications in molecular imaging, although the content of fluorine atoms in these molecules is limited. In this review, we focus mainly on polymer probes that allow higher fluorine content and represent versatile platforms with properties tailorable to a plethora of biomedical in vivo applications. We discuss the chemical development, up to the first imaging applications, of these promising fluorine probes, including injectable polymers that form depots that are intended for possible use in cancer therapy.
- MeSH
- Fluorine chemistry MeSH
- Fluorocarbons chemistry MeSH
- Hydrogen-Ion Concentration MeSH
- Contrast Media chemistry MeSH
- Humans MeSH
- Molecular Probes chemistry MeSH
- Molecular Imaging instrumentation methods MeSH
- Mice MeSH
- Polymers chemistry MeSH
- Scattering, Radiation MeSH
- Reactive Oxygen Species metabolism MeSH
- Light MeSH
- Temperature MeSH
- Fluorine-19 Magnetic Resonance Imaging methods trends MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
In this work, we present the synthesis and evaluation of magnetic resonance (MR) properties of novel phosphorus/iron-containing probes for dual 31P and 1H MR imaging and spectroscopy (MRI and MRS). The presented probes are composed of biocompatible semitelechelic and multivalent phospho-polymers based on poly(2-methacryloyloxyethyl phosphorylcholine) (pMPC) coordinated with small paramagnetic Fe3+ ions or superparamagnetic maghemite (γ-Fe2O3) nanoparticles via deferoxamine group linked to the end or along the polymer chains. All probes provided very short 1H T1 and T2 relaxation times even at low iron concentrations. The presence of iron had a significant impact on the shortening of 31P relaxation, with the effect being more pronounced for probes based on γ-Fe2O3 and multivalent polymer. While the water-soluble probe having one Fe3+ ion per polymer chain was satisfactorily visualized by both 31P-MRS and 31P-MRI, the probe with multiple Fe3+ ions could only be detected by 31P-MRS, and the probes consisting of γ-Fe2O3 nanoparticles could not be imaged by either technique due to their ultra-short 31P relaxations. In this proof-of-principle study performed on phantoms at a clinically relevant magnetic fields, we demonstrated how the different forms and concentrations of iron affect both the 1H MR signal of the surrounding water molecules and the 31P MR signal of the phospho-polymer probe. Thus, this double contrast can be exploited to simultaneously visualize body anatomy and monitor probe biodistribution.
Three magnetic resonance (MR)/fluorescence imaging probes were tested for visualization, cellular distribution, and survival of labeled pancreatic islets in vitro and following transplantation. As T(1) contrast agents (CAs), gadolinium(III) complexes linked to β-cyclodextrin (Gd-F-βCD) or bound to titanium dioxide (TiO2 @RhdGd) were tested. As a T(2) CA, perovskite manganite nanoparticles (LSMO@siF@si) were examined. Fluorescein or rhodamine was incorporated as a fluorescent marker in all probes. Islets labeled with gadolinium(III) CAs were visible as hyperintense spots on MR in vitro, but detection in vivo was inconclusive. Islets labeled with LSMO@siF@si CA were clearly visible as hypointense spots or areas on MR scans in vitro as well as in vivo. All CAs were detected inside the islet cells by fluorescence. Although the vitality and function of the labeled islets was not impaired by any of the tested CAs, results indicate that LSMO@siF@si CA is a superior marker for islet labeling, as it provides better contrast enhancement within a shorter scan time.
- MeSH
- beta-Cyclodextrins chemistry MeSH
- Fluorescent Dyes chemistry MeSH
- Microscopy, Fluorescence MeSH
- Gadolinium chemistry MeSH
- Contrast Media chemistry diagnostic use MeSH
- Metal Nanoparticles chemistry diagnostic use MeSH
- Rats MeSH
- Cells, Cultured MeSH
- Islets of Langerhans cytology metabolism radiography MeSH
- Magnetic Resonance Imaging MeSH
- Rats, Inbred Lew MeSH
- Manganese Compounds chemistry MeSH
- Titanium chemistry MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
Focal cortical dysplasias (FCDs) are a range of malformations of cortical development each with specific histopathological features. Conventional radiological assessment of standard structural MRI is useful for the localization of lesions but is unable to accurately predict the histopathological features. Quantitative MRI offers the possibility to probe tissue biophysical properties in vivo and may bridge the gap between radiological assessment and ex-vivo histology. This review will cover histological, genetic and radiological features of FCD following the ILAE classification and will explain how quantitative voxel- and surface-based techniques can characterise these features. We will provide an overview of the quantitative MRI measures available, their link with biophysical properties and finally the potential application of quantitative MRI to the problem of FCD subtyping. Future research linking quantitative MRI to FCD histological properties should improve clinical protocols, allow better characterisation of lesions in vivo and tailored surgical planning to the individual.
- MeSH
- Phenotype * MeSH
- Humans MeSH
- Magnetic Resonance Imaging methods utilization MeSH
- Malformations of Cortical Development diagnostic imaging genetics pathology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
In magnetic resonance imaging (MRI), paramagnetic complexes are utilized as contrast agents. Much attention has been paid to the development of new contrast agents responsive to pH, temperature or concentration of various components of body liquids. We report a new type of MRI probe sensing the concentrations of calcium and magnesium in biological media. The ligand do3ap(BP) combines a dota-like chelator with a bisphosphonate group. In the complex, the Gd(III) ion is entrapped in the macrocyclic cavity whereas the bisphosphonate group is not coordinated and therefore is available for coordination with endogenous metal ions. In the presence of metal ions, Gd-do3ap(BP) appears to show formation of coordination oligomers leading to an unprecedented increase in r(1) up to 200-500%. The extremely high relaxivity response makes this type of compound interesting for further studies as MRI ion-responsive probes for biomedical research.
Tissue hypoxia becomes the driver of the micro-environmental transformation of the malignant tumorous tissue in majority of solid tumors. Even more, during the development of solid tumors, a large amount of nutrients is consumed due to rapid proliferation of tumor cells. The way of use of nutrients could be assessed using the probes during positron emission tomography (PET), the most frequent is the use of 18F-fluorodeoxyglucose (18F-FDG) demonstrating the turn-over of glucose exploitation in a manner of Warburg phenomenon. Even tumor cells can undergo metabolic reprogramming by changing the expression of glycolysis-related proteins, development of hypoxic condition increases glucose uptake to promote their growth. The hypoxic conditions are stimulation also the development of drug and/or radiation resistance, thus, the identification of the hypoxic tissue could play an important role in therapy planning. The process that enables use of hypoxia specific PET radiopharmaceutical starts when it enters cell by passive diffusion. Intracellularly, a model substance - 18F-fluoromisonidazol (18F-FMISO) is reduced by nitroreductase enzymes to become trapped in cells within reduced tissue oxygen partial pressure. The identification of the hypoxic tissue aids to plan the target to radiotherapy in squamous cell carcinomas of head and neck or cervical carcinoma, when 18F-FMISO-PET/CT is used as a planning procedure for a target volume, while 18F-FDG-PET/MRI is being the local and whole body staging procedure. Hypoxia imaging helps to identify the high-grade component of an astrocytic tumor before stereotactic biopsy.
- MeSH
- Fluorodeoxyglucose F18 MeSH
- Hypoxia MeSH
- Humans MeSH
- Magnetic Resonance Imaging MeSH
- Tumor Microenvironment MeSH
- Head and Neck Neoplasms * MeSH
- Positron Emission Tomography Computed Tomography MeSH
- Tomography, X-Ray Computed MeSH
- Positron-Emission Tomography methods MeSH
- Radiopharmaceuticals MeSH
- Carcinoma, Squamous Cell * MeSH
- Check Tag
- Humans MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Functional MRI (fMRI) has become an important tool for probing network-level effects of deep brain stimulation (DBS). Previous DBS-fMRI studies have shown that electrical stimulation of the ventrolateral (VL) thalamus can modulate sensorimotor cortices in a frequency and amplitude dependent manner. Here, we investigated, using a swine animal model, how the direction and orientation of the electric field, induced by VL-thalamus DBS, affects activity in the sensorimotor cortex. Adult swine underwent implantation of a novel 16-electrode (4 rows x 4 columns) directional DBS lead in the VL thalamus. A within-subject design was used to compare fMRI responses for (1) directional stimulation consisting of monopolar stimulation in four radial directions around the DBS lead, and (2) orientation-selective stimulation where an electric field dipole was rotated 0°-360° around a quadrangle of electrodes. Functional responses were quantified in the premotor, primary motor, and somatosensory cortices. High frequency electrical stimulation through leads implanted in the VL thalamus induced directional tuning in cortical response patterns to varying degrees depending on DBS lead position. Orientation-selective stimulation showed maximal functional response when the electric field was oriented approximately parallel to the DBS lead, which is consistent with known axonal orientations of the cortico-thalamocortical pathway. These results demonstrate that directional and orientation-selective stimulation paradigms in the VL thalamus can tune network-level modulation patterns in the sensorimotor cortex, which may have translational utility in improving functional outcomes of DBS therapy.
- MeSH
- Electric Stimulation methods MeSH
- Deep Brain Stimulation * methods MeSH
- Magnetic Resonance Imaging methods MeSH
- Motor Cortex physiology MeSH
- Neural Pathways physiology MeSH
- Ventral Thalamic Nuclei physiology MeSH
- Subthalamic Nucleus physiology MeSH
- Swine MeSH
- Thalamus physiology MeSH
- Animals MeSH
- Check Tag
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
