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![MRI of Crohn's disease. Virtual endoscopy views of the displayed diseased small bowel segment (arrow) shows mucosal nodularity, ileo-caecal narrowing and minor prestenotic dilatation. Modified from [36].](profile/Jens-Brondum-Frokjaer/publication/23767522/figure/fig2/AS:339198692347907@1457882678349/MRI-of-Crohns-disease-Virtual-endoscopy-views-of-the-displayed-diseased-small-bowel.png)
MRI of Crohn's disease. Virtual endoscopy views of the displayed diseased small bowel segment (arrow) shows mucosal nodularity, ileo-caecal narrowing and minor prestenotic dilatation. Modified from [36].
Source publication
Imaging of the gastrointestinal tract is very useful for research and clinical studies of patients with symptoms arising from the gastrointestinal tract and in visualising anatomy and pathology. Traditional radiological techniques played a leading role in such studies for a long time. However, advances in non-invasive modalities including ultrasoun...
Context in source publication
Context 1
... research group performed MRI and conventional enteroclysis in 36 patients with suspected Crohn's disease who underwent oral administration of plum juice and bulk fibre laxative [36] . Virtual endoscopy was performed with excellent demonstration of the mucosal surface ( Figure 7). The main limitation of virtual endoscopy is the long and cumbersome computer post- processing and a high image quality is needed for this technique. ...
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Citations
... Additionally, co-registration techniques allow for the acquisition of multimodal data, which can further enhance the classification of tissue pathology. These technological advancements will surely cement gastroenterology as a distinct medical specialty [21]. ...
... Additionally, co-registration techniques to acquire multimodal data can further enhance the ability to classify tissue pathology. These developments will solidify the importance of gastroenterology as a distinct medical specialty [21]. ...
... Additionally, there is a trend towards developing and refining "new sub-modalities" based on traditional methods and fusing different modalities into new multimodal concepts. Overall, the future of GI imaging looks very promising and will significantly benefit clinical and research studies of GI diseases [21]. ...
Imaging techniques play a crucial role in the modern era of medicine, particularly in gastroenterology. Nowadays, various non-invasive and invasive imaging modalities are being routinely employed to evaluate different gastrointestinal (GI) diseases. However, many instrumental as well as clinical issues are arising in the area of modern GI imaging. This minireview article aims to briefly overview the clinical issues and challenges encountered in imaging GI diseases while highlighting our experience in the field. We also summarize the advances in clinically available diagnostic methods for evaluating different diseases of the GI tract and demonstrate our experience in the area. In conclusion, almost all imaging techniques used in imaging GI diseases can also raise many challenges that necessitate careful consideration and profound expertise in this field. Core Tip: Accurately diagnosing gastrointestinal (GI) diseases mainly relies on imaging the GI tract. With the latest techniques, one can explore the detailed morphology, biomechanical properties, function, and pathology of the GI tract. Technological advancements are happening rapidly, and there is enormous innovation potential. The main developing trends include faster image acquisition, higher resolution, increased computer power, and improved software for post-processing. Additionally, there is a trend towards developing and refining "new sub-modalities" based on traditional methods and fusing different modalities into new multimodal concepts. Overall, the future of GI imaging looks promising and will significantly benefit clinical and research studies of GI diseases. Citation: Gulinac M, Kiprin G, Tsranchev I, Graklanov V, Chervenkov L, Velikova T. Clinical issues and challenges in imaging of gastrointestinal diseases: A minireview and our experience.
... Visual inspection of gastrointestinal pathology and anatomy has become an important tool for the diagnosis and prognosis of GI diseases. At present, multiple imaging modalities are applied to diagnose these diseases in clinical and basic research, such as endoscopic techniques [3], fluorescence imaging [4,5], X-ray imaging [6], computed tomography (CT) [7,8], magnetic resonance imaging (MRI) [9,10], single-photon emission computed tomography (SPECT) [11], photo acoustic imaging [12,13], and multimodal imaging [14][15][16][17]. However, the endoscopic technique is invasive, which is suboptimal and unfavourable for patient follow-up study [18][19][20][21]. ...
... MRI provides excellent spatial resolution while high cost and time-consuming [23]. X-ray and CT imaging have become the most widely used imaging modes to clinical diagnose of GI diseases for the advantages of simple imaging process, low price and no tissue damage in various non-intrusive imaging techniques [3,24]. In particular, the rising energy spectrum CT technique, which can image an object using two X-ray sources with different properties, has attracted increasing attention [25,26]. ...
Background
Non-intrusive imaging of gastrointestinal (GI) tract using computed tomography (CT) contrast agents is of the most significant issues in the diagnosis and treatment of GI diseases. Moreover, spectral CT, which can generate monochromatic images to display the X-ray attenuation characteristics of contrast agents, provides a better imaging sensitivity for diagnose inflammatory bowel disease (IBD) than convention CT imaging.
Methods
Herein, a convenient and one-pot synthesis method is provided for the fabrication of small-molecule lanthanide complex Holmium-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (Ho-DOTA) as a biosafe and high-performance spectral CT contrast agent for GI imaging with IBD. In vivo CT imaging was administered with both healthy mice and colitis mice induced by dextran sodium sulfate.
Results
We found that Ho-DOTA accumulated in inflammation sites of large intestines and produced high CT contrast compared with healthy mice. Both in vitro and in vivo experimental results also showed that Ho-DOTA provided much more diagnostic sensitivity and accuracy due to the excellent X-ray attenuation characteristics of Ho-DOTA compared with clinical iodinate agent. Furthermore, the proposed contrast media could be timely excreted from the body via the urinary and digestive system, keeping away from the potential side effects due to long-term retention in vivo.
Conclusion
Accordingly, Ho-DOTA with excellent biocompatibility can be useful as a potential high-performance spectral CT contrast agent for further clinical imaging of gastrointestinal tract and diagnosis of intestinal system diseases.
Graphical Abstract
Supplementary Information
The online version contains supplementary material available at 10.1186/s40824-023-00463-x.
... It is one of the most accurate methods for diagnosis of abdominal and gastrointestinal (GI) diseases. The imaging of GI tract nevertheless requires the employment of contrast agents due to the low X-ray absorption of soft tissues [3][4][5]. Barium sulphate is one of the conventional GI contrasting agents which is orally delivered to improve sensitivity and resolution of imaging. However, its use is quite often related to side effects for a patient and sometimes causes imaging artefacts due to insufficient contrast and polydispersity of the low-soluble powder [6]. ...
Bismuth-based compounds are considered to be the best candidates for computed tomography (CT) imaging of gastrointestinal (GI) tract due to high X-ray absorption. Here, we report the introduction of polymer-coated bismuth oxychloride (BiOCl) nanosheets for highly efficient CT imaging in healthy mice and animal with colitis. We demonstrate simple, low cost and fast aqueous synthesis protocol which provides gram-quantity yield of chemically stable BiOCl nanosheets. The developed contrast gives 2.55-fold better CT enhancement compared to conventional contrast with negligible in vivo toxicity. As a major finding we report a regioselective CT imaging of GI tract by using nanoparticles coated with differentially charged polymers. Coating of nanoparticles with a positively charged polymer leads to their fast accumulation in small intestine, while the coating with negatively charged polymers stimulates prolonged stomach retention. We propose that this effect may be explained by a pH-controlled aggregation of nanoparticles in stomach. This feature may become the basis for advancement in clinical diagnosis of entire GI tract.
... A complete understanding of the dissolution and absorption behavior of oral formulations demands an in vivo setup that tracks the movement of formulation inside the GI tract and subsequent diffusion and absorption of API molecules. In fact, recent advances in medical imaging techniques [15,16] allow tracking the fate of a formulation within the GI tract. However, in practice, the dissolution behavior of formulation is often studied using in vitro experiments and the in vivo experiments are limited to the measurement of the plasma drug concentration profile C p (t) of the absorbed API. ...
Bioavailability of oral drug formulations is strongly dependent on the composition of the gastric and intestinal fluids and hydrodynamic conditions in the gastrointestinal tract. These affect the dissolution behavior of oral formulations and their subsequent absorption to the bloodstream. A detailed characterization of all these factors is almost impossible in an in vivo setting, which necessitates the use of in vitro experiments. However, the drug release/drug solubility information in the media representing the gastrointestinal tract obtained in an in vitro study is typically not directly determined in an in vivo experiment. Instead, it is more convenient to determine in vivo the drug concentration in plasma. In vitro–in vivo correlation (IVIVC) typically refers to mathematical relationships between in vitro dissolution behavior and in vivo drug concentration in plasma. IVIVC may be improved by approaches that better mimic in vivo conditions in an in vitro setting. These include mimicking of drug absorption and the composition and hydrodynamics of the release medium. Artificial gastrointestinal (GI) systems are designed to meet this objective. In this review, we discuss our current understanding of the IVIVC and the experimental approaches to improve the IVIVC. Some ex vivo approaches also fall within the scope of this review.
... Various imaging modalities can be used to capture signs of inflammation and gastrointestinal dysfunction. Abdominal CT is also commonly used to visualize the bowels and adjacent structures to uncover obstructions and other anatomical problems affecting the gastrointestinal tract (173). Similarly, FDG-PET/CT is an excellent method for the non-invasive quantification of bowel inflammation, and has been studied extensively in patients with IBD (174). ...
The central nervous system (CNS) is an important regulator of the gastrointestinal tract, and CNS dysfunction can result in significant and disabling gastrointestinal symptom manifestation. For patients with neuroimmunologic and neuroinflammatory conditions, the recognition of gastrointestinal symptoms is under-appreciated, yet the gastrointestinal manifestations have a dramatic impact on quality of life. The current treatment strategies, often employed independently by the neurologist and gastroenterologist, raise the question of whether such patients are being treated optimally when siloed in one specialty. Neuroimmunogastroenterology lies at the borderlands of medical specialties, and there are few resources to guide neurologists in this area. Here, we provide an overview highlighting the potential mechanisms of crosstalk between immune-mediated neurological disorders and gastrointestinal dysfunction.
... Advances in noninvasive imaging modalities including contrast enhanced ultrasound (CEUS), computed tomography (CT), positron emission tomography (PET) and magnetic resonance imaging (MRI) have in the last decades revolutionised the way in which the gastrointestinal tract can be studied. Avoiding radiation exposure, MRI is, besides CEUS, the most favourable technique combining excellent soft tissue contrast, spatial resolution, and depth of penetration [167]. A variety of contrast agents has been evaluated for MRI enterography including paramagnetic gadolinium chelates which reduce the longitudinal T1-relaxation property and result in a brighter signal, and superparamagnetic iron oxide based nanoparticles (SPION) which show size dependent T1-or T2-effects. ...
Nanoscience has flourished with increasing use of nanoparticles in many products. The particles enter the environment and affect both biotic and abiotic components of the ecosystem. Via the water supply and the food chain, humans could be affected by ingesting those particles. In this chapter, we will discuss mechanisms by which nanoparticles or their constituents can be translocated from the gastrointestinal tract, what their fate may be and how relevant this is for human health.
... In the clinic, imaging techniques such as X-ray fluoroscopy, magnetic resonance imaging (MRI), endoscopic ultrasound (EUS) or high-definition white light endoscopy (hWLE) are typically used to evaluate morphological abnormalities, followed by biopsy for diagnosing upper gastrointestinal (GI) disorders [8][9][10][11][12]. Multiple optical imaging techniques such as confocal laser endomicroscopy (CLE) [13], chromoendoscopy [14], narrow band imaging [15] and optical coherence tomography (OCT) [16][17][18][19][20][21][22][23][24][25] have been used in conjunction with hWLE for detecting GI diseases. ...
Pre-clinical studies using murine models are critical for understanding the pathophysiological mechanisms underlying immune-mediated disorders such as Eosinophilic esophagitis (EoE). In this study, an optical coherence tomography (OCT) system capable of providing three-dimensional images with axial and transverse resolutions of 5 µm and 10 µm, respectively, was utilized to obtain esophageal images from a murine model of EoE-like disease ex vivo. Structural changes in the esophagus of wild-type (Tslpr+/+) and mutant (Tslpr−/−) mice with EoE-like disease were quantitatively evaluated and food impaction sites in the esophagus of diseased mice were monitored using OCT. Here, the capability of OCT as a label-free imaging tool devoid of tissue-processing artifacts to effectively characterize murine EoE-like disease models has been demonstrated.
... 4,5 Transabdominal real-time sonography is a non-invasive and versatile tool for imaging the intestines and has gained substantial progress in the last decade when newer techniques were introduced. 6,7 In this study, we report the use of sonography in demonstrating the characteristic images of phase III in three fasting patients. ...
Background:
Migrating motor complex phase III (MMC phase III) of intestine is an important physiological mechanism traditionally recognized by myoelectric recordings or pressure tracings. Direct imaging is difficult and sonographic visualization in human has not been reported.
Methods:
We have demonstrated this unique phenomenon in three patients who underwent abdominal sonographic examinations. Characteristic images were recorded by videotape and both spatial and temporal features were analyzed.
Key results:
Occurrences of multiple equally spaced, rhythmic intestinal contractions were observed. Parameters including wave frequency, propagation velocity, and duration of the events agreed with those of the well-known phase III. The presence of distinct cyclic patterns observed in two and abolition by meal in the other patient further support our conclusion.
Conclusions & inferences:
We conclude that the migrating waves observed in our study represent the human MMC phase III. This unique finding in human subjects merits further investigation.
... In the current issue of World J Gastroenterol, different techniques which are either commercially available or in development are presented. The technologies cover the selected methods to evoke and assess gut pain experimentally and in the clinic [1] ; neuroimaging of the brain-gut axis [2] ; new methods for ultrasound and imaging [3] ; devices to assess sphincter functions and force measurements [4][5][6] ; emerging experimental methods to measure blood flow and histochemical changes in the tissue [7,8] ; manometry and impedance measurements as well as pharmacological and modelling techniques [9,10] . There is no doubt that these methods will revolutionize the diagnostic approach in near future. ...
This issue presents different new techniques aiming to increase our understanding of the gastrointestinal system and to improve treatment. The technologies cover selected methods to evoke and assess gut pain, new methods for imaging and physiological measurements, histochemistry, pharmacological modelling etc. There is no doubt that the methods will revolutionize the diagnostic approach in near future.
The diagnosis of gastrointestinal (GI) tract diseases is frequently performed in clinic, so it is crucial to develop high-performance contrast agents for real-time and non-invasive imaging examination of GI tract. Herein, we show a novel method to synthesize neodymium (Nd) chelate, Nd-diethylenetriaminepentaacetic acid (Nd-DTPA), on a large scale without byproducts for spectral computed tomography (CT) and second near-infrared window imaging of GI tract in vivo. The Nd-DTPA was simply generated by heating the mixture of Nd2O3 and DTPA in water at 85°C for 2 h. This dual-modal imaging agent owns the advantages of a simple and green synthesis route, no need of purification process, high yield (86.24%), large-scale production capability (>10 g in lab synthesis), good chemical stability and excellent water solubility (≈2 g/mL). Moreover, the Nd-DTPA emitted strong near-infrared fluorescence at 1308 nm, and exhibited superior X-ray attenuation ability compared to clinical iohexol. The proposed Nd-DTPA can integrate the complementary merits of dual-modal imaging to realize spatial-temporally and highly sensitive imaging of GI tract in vivo, accurate diagnosis the location of intestinal obstruction and monitor its recovery after surgery. The developed high-efficient method for gram-scale synthesis of Nd-DTPA and the proposed spectral CT and second near-infrared window dual-modal imaging strategy provides a promising way for accurate visualization of GI tract in vivo.
