Contrast Agents

Author(s):  
Resmi A. Charalel ◽  
Martin R. Prince

Imaging is reliant upon the contrast between different body elements, which may be present naturally or may require the introduction of extrinsic contrast agents. Since the 1920s, the use of contrast agents has been refined to enhance the diagnostic potential of multiple imaging modalities. Contrast agents are a vital part of diagnosis and treatment algorithms involving image guidance. Given the wealth of contrast agents on the market, a basic understanding of the various types is critical for budding interventional radiologists who need to use such agents judiciously on a daily basis. Such contrast agents may be administered intravenously, intraarterially, intrathecally, orally, via inhalation, transrectally, or via indwelling tubes or catheters cannulating a specific viscus. In this chapter, we review the key categories, contraindications, and alternatives for such agents, with special attention to their use in an interventional radiology (IR) practice.

VASA ◽  
2018 ◽  
Vol 47 (5) ◽  
pp. 361-375 ◽  
Author(s):  
Harold Goerne ◽  
Abhishek Chaturvedi ◽  
Sasan Partovi ◽  
Prabhakar Rajiah

Abstract. Although pulmonary embolism is the most common abnormality of the pulmonary artery, there is a broad spectrum of other congenital and acquired pulmonary arterial abnormalities. Multiple imaging modalities are now available to evaluate these abnormalities of the pulmonary arteries. CT and MRI are the most commonly used cross-sectional imaging modalities that provide comprehensive information on several aspects of these abnormalities, including morphology, function, risk-stratification and therapy-monitoring. In this article, we review the role of state-of-the-art pulmonary arterial imaging in the evaluation of non-thromboembolic disorders of pulmonary artery.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A422-A422
Author(s):  
Ravi Murthy ◽  
Rahul Sheth ◽  
Alda Tam ◽  
Sanjay Gupta ◽  
Vivek Subbiah ◽  
...  

BackgroundImage guided intra-tumor administration of investigational immunotherapeutic agents represents an expanding field of interest. We present a retrospective review of the safety, feasibility & technical nuances of real-time image guidance for injection & biopsy across a spectrum of extracranial solid malignancies utilizing the discipline of Interventional Radiology.MethodsPatients who were enrolled in image guided intratumoral immunotherapy injection (ITITI) clinical trials over a 6 year period (2013–19) at a single tertiary care cancer center were included in this analysis. Malignancy, location, imaging guidance utilized for ITITI & biopsy for injected (adscopal) & non-injected (abscopal) lesions were determined and categorized. Peri-procedural adverse events were noted.Results262 pts (146 female, 61 yrs median) participating in 29 immunotherapeutic clinical trials (TLR & STING agonists, gene therapy, anti CD-40, viral/bacterial/metabolic oncolytics) met study criteria. Malignancies included melanoma 88, sarcoma 32, colorectal 29, breast 23, lung 17, head & neck 15, ovarian 8, neuroendocrine 7, pancreatic adenocarcinoma 6, 3 each (cholangioCA, endometrial, bladder, GI tract), 2 each (RCC, thymicCA, lymphoma, merkel cell, prostate) & others 1 each (CUP, GIST, dermatofibrosarcoma, DSRT, neuroblastoma, thyroid). All 169 & 93 patients received the intended 1371 ITITI in parietal (abdominal/chest wall, extremity, neck, pelvis) or visceral (liver, lung, peritoneum, adrenal) locations respectively; 83 patients received lymph node injections within either location. Imaging guidance was US in 68% of the cohort (US 161, CT+US 19); CT was used in 30% (81) & MRI in 1 patient. Median diameter of the ITITI lesion was 32 mm (8–230 mm). Median volume of the ITITI therapeutic material/session was 2 ml (1–6.9 ml). Lesions were accessed using a coaxial technique. ITITI delivery needles used at operator preference & tailored to lesion characteristics were either a 21G/22G Chiba, 21G Profusion (Cook Medical), 22G Morrison (AprioMed), 25G hypodermic (BD) & 18G Quadrafuse (Rex Medical). 2840 core biopsies (>18G Tru-cut core, Mission, Bard Medical) were performed in 237 patients during 690 procedures; biopsy sessions were often concurrent & of the ITITI site. 137 patients also underwent biopsy of a non-ITITI site (89 parietal location). Dimensions of the non-ITITI lesion were median 10 mm (7–113 mm); US image guidance was used in 97 patients (72%) to obtain a total of 1257, >18G Tru-core samples. 1.3% of injections resulted in SAE (NCI CTC AE >3) and 0.5% of 4097 biopsies developed major complications (SIR Criteria); both categories were manageable.ConclusionsUtilizing real time image guidance, ITITI to the administration of a myriad of investigational immunotherapeutic agents with concomitant biopsy procedures to date are associated with a high technical success rate & favorable safety profile.AcknowledgementsJoshua Hein, Mara Castaneda, Jyotsna Pera, Yunfang Jiang,Shuang Liu, Holly Liu and Anna LuiTrial RegistrationN/AEthics ApprovalThe study was approved by Institution’s Ethics Board, approval number 2020-0536: A retrospective study to determine the safety, feasibility and technical challenges of real-time image guidance for intra-tumor injection and biopsy across multiple solid tumors.Consent2020-0536 Waiver of Informed ConsentReferenceSheth RA, Murthy R, Hong DS, et al. Assessment of image-guided intratumoral delivery of immunotherapeutics in patients with cancer. JAMA Netw Open 2020;3(7):e207911. doi:10.1001/jamanetworkopen.2020.7911


Neurosurgery ◽  
2020 ◽  
Author(s):  
Bledi C Brahimaj ◽  
Ryan B Kochanski ◽  
John J Pearce ◽  
Melike Guryildirim ◽  
Carter S Gerard ◽  
...  

Abstract The goal of glioma surgery is maximal safe resection in order to provide optimal tumor control and survival benefit to the patient. There are multiple imaging modalities beyond traditional contrast-enhanced magnetic resonance imaging (MRI) that have been incorporated into the preoperative workup of patients presenting with gliomas. The aim of these imaging modalities is to identify cortical and subcortical areas of eloquence, and their relationship to the lesion. In this article, multiple modalities are described with an emphasis on the underlying technology, clinical utilization, advantages, and disadvantages of each. functional MRI and its role in identifying hemispheric dominance and areas of language and motor are discussed. The nuances of magnetoencephalography and transcranial magnetic stimulation in localization of eloquent cortex are examined, as well as the role of diffusion tensor imaging in defining normal white matter tracts in glioma surgery. Lastly, we highlight the role of stimulated Raman spectroscopy in intraoperative histopathological diagnosis of tissue to guide tumor resection. Tumors may shift the normal arrangement of functional anatomy in the brain; thus, utilization of multiple modalities may be helpful in operative planning and patient counseling for successful surgery.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Tomoko Mizota ◽  
Masato Suzuoki ◽  
Saya Kaku ◽  
Kenichi Mizunuma ◽  
Kazuto Ohtaka ◽  
...  

Abstract Background Sarcoid-like reaction (SLR) is a histological pattern of granulomatous inflammation that is clinically differentiated from sarcoidosis. Since SLR is known to occur in several neoplasias and occasionally causes lymphadenopathy and mimics metastatic malignancy, it needs to be considered whether lymphadenopathy is due to metastasis or SLR for the choice of cancer treatment. Few cases of hepatocellular carcinoma (HCC) with SLR have been reported. Here, a case of HCC with lymphadenopathy diagnosed as SLR without metastasis is presented. Case presentation A 69-year-old woman was admitted to our hospital because of upper abdominal pain. She tested positive for hepatitis C virus ribonucleic acid. Imaging modalities showed an 81 × 65-mm-sized tumor with multiple nodules in segment 3 and a 17 × 12-mm-sized tumor in segment 5 with a common HCC enhancement pattern. In addition, a lymph node in the hepatoduodenal ligament was enlarged at 13 mm in size, suggesting the metastasis of HCC. Hepatectomy of the lateral segment and segment 5 and lymph node dissection in the hepatoduodenal ligament were performed. Both tumors in segments 3 and 5 were pathologically diagnosed as HCC without vessel invasion. The tumors contained necrotic cells and epithelioid cell granulomas with multinucleated giant cells, which is typically observed in sarcoidosis. The dissected lymph nodes also contained epithelioid cell granulomas, as well as giant cells with asteroid bodies. There was no malignancy in the lymph nodes. The pathological findings suggested the coexistence of malignancy and sarcoidosis. However, since the patient did not show any typical findings of pulmonary or cardiac sarcoidosis, the case was diagnosed as HCC with SLR in the primary lesion and regional lymph nodes. Conclusions SLR needs to be considered in the differential diagnosis when a cancer patient develops lymphadenopathy. However, lymphadenopathy due to SLR is indistinguishable from that due to metastasis even when using multiple imaging modalities. Pathological examinations may be helpful for the diagnosis.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1950
Author(s):  
Rossella Canese ◽  
Federica Vurro ◽  
Pasquina Marzola

Starting from the mid-1990s, several iron oxide nanoparticles (NPs) were developed as MRI contrast agents. Since their sizes fall in the tenths of a nanometer range, after i.v. injection these NPs are preferentially captured by the reticuloendothelial system of the liver. They have therefore been proposed as liver-specific contrast agents. Even though their unfavorable cost/benefit ratio has led to their withdrawal from the market, innovative applications have recently prompted a renewal of interest in these NPs. One important and innovative application is as diagnostic agents in cancer immunotherapy, thanks to their ability to track tumor-associated macrophages (TAMs) in vivo. It is worth noting that iron oxide NPs may also have a therapeutic role, given their ability to alter macrophage polarization. This review is devoted to the most recent advances in applications of iron oxide NPs in tumor diagnosis and therapy. The intrinsic therapeutic effect of these NPs on tumor growth, their capability to alter macrophage polarization and their diagnostic potential are examined. Innovative strategies for NP-based drug delivery in tumors (e.g., magnetic resonance targeting) will also be described. Finally, the review looks at their role as tracers for innovative, and very promising, imaging techniques (magnetic particle imaging-MPI).


2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
J Hunter

Abstract Aim To highlight the importance of appropriate imaging modalities for abnormal clinical presentations. Method Xyo woman presented with severe right upper-quadrant pain to the emergency department. Prior history of colicky abdominal pain for 1 year, right-sided nephrectomy and hypertension. She stated that the current epsiode of pain was the worst so far, becoming more persistent, prompting her to call an ambulance. Cholecystitis was suspected, so a Computed Tomography abdomen/pelvis was performed. A dilated, inflamed gallbladder was noted in contact with the right psoas major, with what appeared to be an abscess in the right psoas major. Results A Magnetic Resonance Cholangiopancreatography was performed, which demonstrated that the aforementioned abscess was in fact a large cavity within the psoas major, containing up to 15 gallstones. Cholelithiasis was also seen, with common bile duct dilatation and evidence of a common bile duct stone. An Endoscopic Retrograde Cholangiopancreatography was performed, and X recovered well post-procedure with analgesia and antibiotics. Conclusions Acute cholecystitis/intra-abdominal gallstones may result in abscess/cavity formations and abnormal biliary clinical presentations. It is important therefore to fully investigate abnormal hepatobiliary imaging with multiple imaging modalities to allow for accurate diagnosis and appropriate further management of presentations.


ACS Nano ◽  
2010 ◽  
Vol 4 (11) ◽  
pp. 6579-6586 ◽  
Author(s):  
Jai Il Park ◽  
Dinesh Jagadeesan ◽  
Ross Williams ◽  
Wendy Oakden ◽  
Siyon Chung ◽  
...  

2021 ◽  
pp. 289-304
Author(s):  
F. Gonca Eldem ◽  
Bora Peynircioğlu

2020 ◽  
Vol 98 (5) ◽  
pp. 612-623
Author(s):  
Adam Tepperman ◽  
David Jiao Zheng ◽  
Maria Abou Taka ◽  
Angela Vrieze ◽  
Austin Le Lam ◽  
...  

Using multiple imaging modalities while performing independent experiments in parallel can greatly enhance the throughput of microscopy-based research, but requires the provision of appropriate experimental conditions in a format that meets the optical requirements of the microscope. Although customized imaging chambers can meet these challenges, the difficulty of manufacturing custom chambers and the relatively high cost and design inflexibility of commercial chambers has limited the adoption of this approach. Herein, we demonstrate the use of 3D printing to produce inexpensive, customized, live-cell imaging chambers that are compatible with a range of imaging modalities, including super-resolution microscopy. In this approach, biocompatible plastics are used to print imaging chambers designed to meet the specific needs of an experiment, followed by adhesion of the printed chamber to a glass coverslip, producing a chamber that is impermeant to liquids and that supports the growth and imaging of cells over multiple days. This approach can also be used to produce moulds for casting microfluidic devices made of polydimethylsiloxane. The utility of these chambers is demonstrated using designs for multiplex microscopy, imaging under shear, chemotaxis, and general cellular imaging. Together, this approach represents an inexpensive yet highly customizable approach for producing imaging chambers that are compatible with modern microscopy techniques.


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