Intravenous Injection Of Contrast Medium Research Articles

CEM immediately after contrast-enhanced CT: a one-step staging of breast cancer

BackgroundContrast-enhanced mammography (CEM) is a promising technique. We evaluated the diagnostic potential of CEM performed immediately after contrast-enhanced computed tomography (CE-CT).MethodsFifty patients with breast cancer underwent first CE-CT and then CEM without additional contrast material injection. Two independent radiologists evaluated CEM images. The sensitivity of CEM for detecting index and additional malignant lesions was compared with that of mammography/ultrasonography by the McNemar test, using histopathology as a reference standard. Interobserver agreement for detection of malignant lesions, for classifying index tumors, and for evaluating index tumor size and extent was assessed using Cohen κ. Pearson correlation was used for correlating index tumor size/extent at CEM or mammography/ultrasonography with histopathology.ResultsOf the 50 patients, 30 (60%) had unifocal disease while 20 (40%) had multicentric or multifocal disease; 5 of 20 patients with multicentric disease (25%) had bilateral involvement, for a total of 78 malignant lesions, including 72 (92%) invasive ductal and 6 (8%) invasive lobular carcinomas. Sensitivity was 63/78 (81%, 95% confidence interval 70.27–88.82) for unenhanced breast imaging and 78/78 (100%, 95.38–100) for CEM (p < 0.001). The interobserver agreement for overall detection of malignant lesions, for classifying index tumor, and for evaluating index tumor size/extent were 0.94, 0.95, and 0.86 κ, respectively. For index tumor size/extent, correlation coefficients as compared with histological specimens were 0.50 for mammography/ultrasonography and 0.75 for CEM (p ≤ 0.010).ConclusionsCEM acquired immediately after CE-CT without injection of additional contrast material showed a good performance for local staging of breast cancer.Relevance statementWhen the CEM suite is near to the CE-CT acquisition room, CEM acquired immediately after, without injection of additional contrast material, could represent a way for local staging of breast cancer to be explored in larger prospective studies.Key points• CEM represents a new accurate tool in the field of breast imaging.• An intravenous injection of iodine-based contrast material is required for breast gland evaluation.• CEM after CE-CT could provide a one-stop tool for breast cancer staging.Graphical

Effect of Nonionic Iodinated Contrast Media on Blood Pressure during Contrast-enhanced Computed Tomography of Abdomen Examination: A Cross-sectional Study

ABSTRACT Introduction: Computed tomography (CT) scan has high sensitivity and specificity for numerous conditions. The images produced by a CT scanner can be enhanced using iodinated contrast media. Significant hemodynamic changes are seen with rapid intravenous contrast media injection. The average acceptable blood pressure (BP) value is 120/80 mmHg. Many studies have related hypertensive crises with high-osmolar contrast media, whereas its relation with low-osmolar contrast media is still unclear. This study aims to evaluate the effect of nonionic iodinated contrast media on BP during contrast-enhanced CT (CECT) of the abdomen. Materials and Methods: A cross-sectional study was conducted from April 2022 to August 2023. A total of 146 subjects (73 males and 73 females were included in the study). Statistical analysis of data was done using SPSS 23.0. A comparison of systolic BP and diastolic BP across the three periods was done using repeated measures of ANOVA. A between-group comparison was performed by unpaired t-test. The level of significance was set as 5%. All subjects underwent a CECT abdomen, including a plain, arterial, and venous phase. A bolus of 80 mL of Ultravist was administered. BP was measured before the contrast injection (baseline value), between the arterial and venous phases, and 3 min after the contrast injection. Results: Injection of nonionic contrast media caused a decrease in BP among subjects. The mean systolic BP readings before contrast injection in males and females were 127.5 ± 8 mmHg and 122.8 ± 8.4 mmHg, respectively. The mean diastolic BP before contrast injection was 79.2 ± 6.4 and 76 ± 6.4 mmHg among males and females, respectively. For systolic, these values decreased to 123 ± 10.3 mmHg in males and in females to 115 ± 14.6 mmHg when measured between arterial and venous phases. Similarly, for diastolic BP, the mean values recorded between the arterial-venous phase reduced to 76.7 ± 9.3 mmHg and 72.3 ± 10 mmHg, respectively. The BP readings, however, increased near baseline value when measured 3 min after the injection. The mean systolic BP measured 126.1 ± 8.5 mmHg and 124.9 ± 11.8 mmHg for males and females at 3 min after injection. Similarly, the mean diastolic BP values taken after 3 min of contrast injection were 78.3 ± 6.5 mmHg and 76.2 ± 7 mmHg in males and females, respectively, P &lt; 0.001. BP in both male and female groups was affected similarly. Conclusion: Bolus administration of 80 mL of Ultravist reduced BP. This reduction was short-term and got back to normal within a few minutes. The contrast media similarly affected both genders. The BP changes had no clinical significance.

Use of New Ultrasonography Methods for Detecting Neoplasms in Dogs and Cats: A Review.

The aim of this literature review was to present the novel imaging modalities elastography and contrast-enhanced ultrasonography. We provided an overview of the concepts and applications of each technique for the investigation of neoplastic and metastatic tumors in dogs and cats. Studies on elastography are based on the elasticity and deformation of the evaluated tissue. The information obtained from the different types of elastography can aid in the detection and differentiation of malignant and benign structures. Descriptions of elastography studies in several organs and tissue in veterinary medicine reported that, in general, malignant tumors tend to be more rigid and, therefore, less deformable than benign lesions or in comparison to the healthy parenchyma. Contrast-enhanced ultrasonography is based on the intravenous injection of contrast media constituted by microbubbles. This imaging modality can be performed in nonsedated animals and provides information on the tissue perfusion, allowing the investigation of macro- and micro-circulation. Studies on different organs and tissues were performed in dogs and cats and revealed a tendency of malignant tumors to present faster transit of the contrast media (time to wash-in, peak and wash-out). These advanced techniques can be associated with other imaging modalities, aiding important information to the well-established exams of B-mode and Doppler ultrasonography. They can be used as screening tests, potentially representing an alternative to the invasive sampling methods required for cytological and histopathological analysis.

Exploring the implementation of role extension for Namibian radiographers: Perspectives on intravenous injection of contrast media

IntroductionRole extension to include intravenous (IV) injection of contrast media has been formally embraced by radiographers and their regulatory bodies in developed countries. The revised scope of practice, in our Namibian context, has formalised IV injection as an extended role for radiographers. This study aimed to explore the perspectives of radiographers regarding this new role of IV injection of contrast media. MethodsA qualitative design with a descriptive phenomenological approach was employed to collect data from 15 radiographers working in both public and private radiology facilities. Participants were purposively selected to participate in focus group discussions and individual interviews. An interview guide was used to facilitate the discussions and interviews, and a voice recorder was used for recording. Data were transcribed verbatim and analysed using Tesch's 8-step method. ResultsFrom the 15 participants, three themes were developed: enhanced service delivery with two subthemes (improved departmental workflow and patient care), training needs with two subthemes (inadequate contrast media reaction training and standardised training requirement), and medical-legal issues with two subthemes (regulatory blurriness and role conflict distress). ConclusionThe participants expressed mixed perceptions towards the IV injection role of radiographers, emphasising the benefits for the department and patients while raising concerns regarding standardisation of training and associated medico-legal issues. Furthermore, a large-scale evaluation is necessary to uncover the challenges and barriers to the successful adoption of this new role. Implications for practiceThe role extension for radiographers to include IV injections is a long-awaited development, but it should be accompanied by the necessary training and guidelines to fully realise its benefits.

Transarterial ethiodised oil marking before CT-guided renal cryoablation: evaluation of tumour visibility in various renal cell carcinoma subtypes

To evaluate ethiodised oil retention of transarterial embolisation using ethiodised oil (ethiodised oil marking) before computed tomography (CT)-guided percutaneous cryoablation (PCA) according to renal cell carcinoma (RCC) subtype. Ethiodised oil marking was performed 1-3 days before PCA in 99 patients with 99 RCCs from 2016 to 2020. Ethiodised oil retention on CT images was evaluated retrospectively and CT attenuation values in the tumour were measured. Regions of interest (ROI) were placed on the tumours to calculate: average (ROI-average), maximal (ROI-max), minimum (ROI-min), and standard deviation (ROI-SD). Qualitative scores comprising a five-point scale (5, excellent; 1, poor) were evaluated for the retention scores (RS) of ethiodised oil in the tumour (ethiodised oil-RS) and the visualisation scores (VS) of the boundary between the tumour and renal parenchyma (boundary-VS). The histological subtypes comprised clear cell (ccRCC; n=85), papillary (pRCC; n=6), and chromophobe/oncocytoma renal cell carcinoma (chrRCC; n=8). The mean ROI-average, ROI-max, and ROI-SD were significantly higher in ccRCCs than in chrRCCs and pRCCs (p<0.05). The mean ethiodised oil-RS was significantly lower in pRCCs than in ccRCCs (p=0.039), and the mean boundary-VS was >4 in all subtypes. Even with poor intratumour ethiodised oil retention (n=6), sufficient boundary-VS was obtained due to "inverted marking." All PCA procedures were completed without additional intravenous contrast material injection at the time of PCA. Regardless of the tumour subtypes, ethiodised oil marking aids in visualising the boundary between the tumour and parenchyma on non-contrast CT in PCA.

Transient Small Bowel Angio-oedema Secondary to Intravenous Iodinated Contrast Medium

We report the clinical profile and computed tomography (CT) findings of a rare case of transient angio-edema of the small bowel following intravenous administration of non-ionic iodinated contrast material in a 36-year-old woman. The pre-contrast CT showed normal small bowel and large bowel wall thickness. Findings included long segment, circumferential bowel wall thickening involving the duodenum, jejunum, and almost the entire ileum on CT scan obtained following the intravenous contrast material injection. The large bowel wall appeared normal in post contrast images also. There was no mesenteric fat stranding, ascites or significant lymphadenopathy. This entity, like most contrast-induced adverse reactions, has a favorable clinical outcome with aggressive clinical monitoring and supportive measures.

Embolic Events After Computed Tomography Contrast Injection in Patients With Interatrial Shunts: A Cohort Study.

Patients with interatrial shunts (patient foramen ovale/atrial septal defect) are potentially at increased risk for paradoxical air embolism following computed tomography (CT) scans with intravenous (IV) contrast media injection. IV in-line filters aim to prevent such embolisms but are not compatible with power injection required for diagnostic CT. The purpose of this study was to determine whether the incidence of paradoxical embolism to the heart and brain in patients with an interatrial shunt is higher compared with controls within 48 hours following injection of IV contrast media without IV in-line filter. This is a retrospective cohort study conducted at a large tertiary academic center, which included a total of 2929 consecutive patients who underwent 8983 CT scans with IV contrast media injection between July 1, 2000 and April 30, 2018. Diagnosis of an interatrial shunt was confirmed by transthoracic or transesophageal echocardiography. Incidence and risk of cardiac embolic events (new troponin elevation, >0.1ng/mL) and neurological embolic events (new diagnosis of stroke/transient ischemic attacks) were evaluated. Among the 2929 patients analyzed (mean±SD age, 61±14y), 475/2929 (16.2%) patients had an interatrial shunt. After applying the exclusion criteria, new elevated troponin was found in 8/329 (2.4%; 95% confidence interval [CI]: 1.1-4.7) patients with an interatrial shunt compared with 25/1687 (1.5%; 95% CI: 0.9-2.2) patients without an interatrial shunt. New diagnosis of stroke occurred in 2/169 (1%; 95% CI: 0.3-4.2) of patients with an interatrial shunt compared with 7/870 (0.8%; 95% CI: 0.4-1.7) without interatrial shunt. Among patients with echocardiographic evidence of an interatrial shunt, IV CT contrast administration without an in-line filter does not increase the incidence of cardiac or neurological events.

The Effect of Fluorescein Angiography on Renal Function: A Meta-analysis and Systematic Review

Background. Contrast-induced nephropathy (CIN) is a complication that occurs in patients undergoing an imaging procedure with intravenous injection of contrast media, most notably iodinated dyes. Fluorescein angiography is a diagnostic procedure performed by ophthalmologists to determine abnormalities in retinal blood vessels. It uses sodium fluorescein, an organic dye, to capture and visualize these blood vessels. There have been conflicting data and practices on how to approach the procedure especially in patients with renal insufficiency. Objective. To determine the risk of CIN among patients undergoing fluorescein angiography. Methods. We searched PubMed, HerdIn, Cochrane Library, and Google Scholar, for published articles on the topic. Other sources were searched for unpublished data or ongoing clinical trials. All research articles pertaining to fluorescein angiography and its effect on renal function with serum creatinine monitoring were included. Two independent authors separately screened records, assessed full texts, and extracted data. We used RevMan computer software to analyze data from the included studies. The primary outcome was the risk of CIN among patients undergoing fluorescein angiography based on the differences on serum creatinine levels and estimated glomerular filtration rates pre- and post-angiography, while the secondary outcome included risk factors for CIN. Results. A total of 6 studies were included in the meta-analysis. Four studies had poor quality as assessed using the Newcastle-Ottawa Scale. One study was deemed to have good quality. Data analysis showed that hemoglobin (p = 0.002) and albumin (p &lt; 0.001) levels may be associated with CIN using sodium fluorescein but were not independent risk factors for CIN (multivariable logistic regression, p = 0.648 and p = 0.069, respectively); while sex, diabetes mellitus and chronic kidney disease were not significantly associated. As a primary outcome, only 6.8% of included patients had CIN with serum creatinine levels post-exposure showed significant differences from baseline values (mean difference 0.05; 95% CI 0.02, 0.07; I2 = 49%), but translating it to eGFR yielded non-significant differences (mean difference -0.37; 95% CI -2.33, 1.59; I2 = 0%). Conclusion. Among patients undergoing fluorescein angiography, sodium fluorescein does not pose an increased risk for CIN.

Power-Injectable Peripherally Inserted Central Catheter Tip Malposition After Power Injection of Intravenous Contrast Media for Computed Tomography Examinations

The aim of this study is to describe the incidence of peripherally inserted catheter tip (PICC) migration after power injection of intravenous contrast for computed tomography (CT) examinations. Retrospective review was conducted of all PICC power injections for CT examinations during the study period: October 16, 2017 through October 23, 2018. Review included evaluation of preinjection and postinjection topograms to assess PICC tip position. Chi-squared statistical analysis was applied. A total of 594 topograms were obtained of power-injectable PICCs during the study period in anticipation of power injection with iodinated contrast media. Of those, 550 patients had satisfactory preinjection topograms and available postinjection topograms; 43 (7.8%) demonstrated tip malposition attributable to power injection of contrast media. Anatomic side of PICC placement and subsequent malposition were independent variables by chi-square test (chi-square = .09, P = .76); 32 of 429 (7.5%) right-sided PICCs versus 11 of 121 (9.1%) left-sided PICCs demonstrated new malposition after contrast media power injection. No complications related to power injection of contrast media through these PICCs were observed. PICC tip malposition secondary to power injection of iodinated contrast media is common and readily identifiable. Obtaining both preinjection and postinjection topograms ensures appropriate catheter position during injection and upon patient departure. Rapid saline flush is a noninvasive maneuver that allows a high chance of successful repositioning of catheter tips. Power injection of contrast media through a power injectable PICC is safe.

EEG NEUROFEEDBACK IN THE TREATMENT OF COGNITIVE DYSFUNCTIONS AFTER THE INFECTION OF SARS-COV-2 AND LONG COVID-19

Coronavirus disease 2019 (COVID-19) is likely to have long-term mental health effects on individuals who have recovered from COVID-19. According to Centers for Disease Control and Prevention (CDC), individuals diagnosed with COVID-19 can see a range of long-term side effects. The aim of the study was to evaluate the effectiveness of neurotherapy (EEG neurofeedback and goal-oriented cognitive training) in the treatment of neurocognitive dysfunctions in a patient after the infection of SARS-CoV-2 and the long long-term side effects after the contraction of COVID-19. The 48-year-old woman ZR, an accountant by profession, an employee of the administration of the Municipal Board of Municipal Resources, fell ill on October 13, 2020. The disease began with very severe burning headache, eyeballs pain, muscle aches. Ten days later more symptoms joined: loss of smell (anosmia) and loss of taste (ageusia), hearing disorders, shortness of breath and chest pains. The symptoms were associated with SARS-CoV-2 coron- avirus infection confirmed by an rt-PCR genetic test. Brain MRI with intravenous paramagnetic contrast medium injection did not show either lesions of acute microischemic significance or areas of pathological enhancement after paramagnetic contrast medium ad- ministration. The patient was treated at home. In mid-November 2020, about a month after the infection of SARS-CoV-2 and con- tracting NeuroCOVID-19, neurocognitive impairment developed and after half a year she was deteriorating and not able to live in- dependently in society because of her condition. She called her problem "brain fog", and was referred for further diagnosis and therapy to the Reintegration and Training Center of the Polish Neuropsychological Society. We diagnosed a range of long-term side effects and introduced neurotherapy (EEG neurofeedback and goal-oriented cognitive training) in the treatment of neurocognitive dysfunctions. It was found that almost all the long-term side effects were reduced in magnitude. The patient improved and she was able to return to work. EEG neurofeedback and goal-oriented cognitive training might be helpful in the reduction of neurocognitive dysfunctions in patients following the infection of SARS-CoV-2 and long-term side effects after the contraction of COVID-19.

Contrast-enhanced MRI T1 Mapping for Quantitative Evaluation of Putative Dynamic Glymphatic Activity in the Human Brain in Sleep-Wake States.

Background Evaluation of the glymphatic system with intrathecal contrast material injection has limited clinical use. Purpose To investigate the feasibility of using serial intravenous contrast-enhanced T1 mapping in the quantitative evaluation of putative dynamic glymphatic activity in various brain regions and to demonstrate the effect of sleep on glymphatic activity in humans. Materials and Methods In this prospective study from May 2019 to February 2020, 25 healthy participants (mean age, 25 years ± 2 [standard deviation]; 15 men) underwent two cycles of MRI (day and night cycles). For each cycle, T1 maps were acquired at baseline and 0.5, 1, 1.5, 2, and 12 hours after intravenous contrast material injection. For the night cycle, participants had a normal night of sleep between 2 and 12 hours. The time (tmin) to reach the minimum T1 value (T1min), the absolute difference between baseline T1 and T1min (peak ΔT1), and the slope between two measurements at 2 and 12 hours (slope[2h-12h]) were determined from T1 value-time curves in cerebral gray matter (GM), cerebral white matter (WM), cerebellar GM, cerebellar WM, and putamen. Mixed-model analysis of variance (ANOVA), Friedman test, and repeated-measures ANOVA were used to assess the effect of sleep on slope(2h-12h) and to compare tmin and peak ΔT1 among different regions. Results The slope(2h-12h) increased from the day to night cycles in cerebral GM, cerebellar GM, and putamen (geometric mean ratio [night/day] = 1.4 [95% CI: 1.2, 1.7], 1.3 [95% CI: 1.1, 1.4], and 2.4 [95% CI: 1.6, 3.6], respectively; P = .001, P < .001, and P < .001, respectively). Median tmin values were 0.5 hour in cerebral and cerebellar GM and putamen for both cycles. Cerebellar GM had the highest mean peak ΔT1, followed by cerebral GM and putamen in both day (159 msec ± 6, 99 msec ± 4, and 62 msec ± 5, respectively) and night (152 msec ± 6, 104 msec ± 6, and 58 msec ± 4, respectively) cycles. Conclusion Clearance of a gadolinium-based contrast agent was greater after sleep compared with daytime wakefulness. These results suggest that sleep was associated with greater glymphatic clearance compared with wakefulness. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Anzai and Minoshima in this issue.

State of art and optimization perspectives for breast imaging

Breast screening with mammography is the most effective method of detecting early-stage breast cancer and reducing related mortality. Among the intrinsic limits of mammography, in terms of clinical performance, the overlapping of normal and pathological tissues is one of the most influential. Some new techniques as Digital Breast Tomosynthesis (DBT) is expected to overcome this limitation by providing a quasi-three-dimensional (3D) image that could lead to improve the accuracy of mammography. Another way to increase accuracy and sensitivity is represented by a double exposure of the patient before and after intravenous injection of contrast media, this technique is called Contrast-enhanced digital (or spectral) mammography (CEDM, CESM). Furthermore, highly specialized software has been developed which is able to detect suspicious mammographic findings. This technology is very interesting especially in the screening field, in fact there are multiple ongoing studies evaluating the use of Artificial Intelligence (AI) as a second reader.To date, screening mammography is the only imaging modality that has proven to significantly lower breast cancer mortality. Tomosynthesis demonstrated excellent sensitivity and specificity but the technique did not meet the expectations given the risk of over diagnosis as well as the lack of reduction in the number of interval breast cancer. CESM could in some cases serve as an alternative imaging tool to MRI. AI, seems to be competing with the breast radiologist and its use as a second reader in breast screening programs is already being proposed.

POS-024 THE EFFECT OF FLUORESCEIN ANGIOGRAPHY ON RENAL FUNCTION: A META-ANALYSIS AND SYSTEMATIC REVIEW

Contrast-induced nephropathy is one of the complications occurring in patients undergoing an imaging procedure requiring intravenous injection of contrast media, most notably iodinated dyes. Fluorescein angiography is a diagnostic procedure offered by ophthalmologists in determining abnormalities in retinal blood vessels. It uses sodium fluorescein, an organic dye, to capture and visualize these blood vessels. There has been conflicting data and practices on how to approach the procedure especially in patients with renal insufficiency.

Frontal Cystic Meningioma Removed by a Partial Transfrontal Craniotomy in a Cat

Background: Meningiomas are the most frequently reported intracranial tumors in cats. It is known to arise at the point of arachnoid cells project into the dural venous sinuses. Cats with intracranial meningiomas are treated by surgical management as the tumors are commonly delineated from normal brain tissue and are not likely to adhere to the cerebral parenchyma. Although meningioma is the most common intracranial tumor in cats, the incidence of cystic meningioma is low. The objective of the current study is to report a case of frontal cystic meningioma with peritumoral cystic structure removed by a partial transfrontal craniotomy. Case: A 10-year-old castrated British shorthair cat was referred to the Baeksan Feline Medical Center with a recent onset of seizures. On the physical examination, the patient was bright and alert. Neurological examinations were unremarkable at the time of presentation. Hematologic examinations were within normal limits. Thoracic and abdominal radiography, and abdominal ultrasonography revealed unremarkable findings. Magnetic resonance imaging revealed an extra-axial mass cranial to the frontal lobe. On the sagittal plane, a cystic structurewas identified in the frontal areaon post-contrast T1W images. No contrast enhancement of the cystic wall was identified after intravenous injection of contrast medium on T1W. On the transverse plane of T2W images, midline shift to the left due to peritumoral edema was observed. The mass was removed via partial transfrontal craniotomy. Postoperative radiography was performed to ensure appropriate placement of the mesh. The patient recovered uneventfully after anesthesia. After the surgery, the patient was closely monitored in an intensive care unit between 24 and 48 h. Based on the histologic findings, the final diagnosis was a fibroblastic meningioma. Nineteen months after the surgery, there was no seizure activity identified by the owner.Discussion: Depending on the location of the cyst, meningiomas can be classified into 4 types according to the human literature. In types 1 and 2, the whole cyst is located within the tumor, resulting in contrast enhancement of the cystic wall. In types 3 and 4, the cysts are located outside the tumor, and no contrast enhancement of the cystic wall is observed. In type 3, the cyst lies adjacent to the brain parenchyma rather than adjacent to the tumor and the meningioma is related to a cerebrospinal fluid cyst bordered by the arachnoid. It is important to classify the type of cystic meningioma prior to surgery in order to decide whether to remove the cystic wall. In type 2, the cystic wall is infiltrated by tumor cells, while the cystic wall of type 3 meningioma is composed of gliotic tissue without any tumor cells. Therefore, in type 2, the meningiomas with cystic walls should be removed for the prevention of recurrence, while in type 3 meningioma, the tumor can be managed by cyst decompression and excision of the solid component. Based on the Nauta classification, the cystic meningioma reported here was considered to be type 3. Therefore, the surgical procedure aimed to remove the solid component of the mass, leaving the cystic wall attached to the normal brain. As the solid part of the meningioma was located beneath the internal plate of the left frontal bone, the partial transfrontal craniotomy was sufficient to expose and remove the entire mass. To the author’s knowledge, this is first case report describing a patient with frontal meningioma with a peritumoral cyst removed by a partial transfrontal craniotomy based on the Nauta classification.

Effects of Water-Based Contrast Media on Experimentally Induced Established Atherosclerotic Plaques in Rabbits

INTRODUCTION: Imaging techniques involving optical coherence tomography, computed tomography (CT) and high-resolution magnetic resonance imaging (MRI) are used as tools to identify atherosclerotic plaques. However, the effects of water-based contrast media used in Post Mortem Computed Tomography Angiography (PMCTA) on the histopathology of atherosclerotic plaques have not been widely explored. The objective of this study is to determine the effects of water-based contrast media used in PMCTA on the histopathology of atherosclerotic plaques and biomarkers of atherosclerosis in experimentally induced established atherosclerotic rabbits. MATERIALS AND METHODS: Twenty male New Zealand white rabbits were divided into 2 groups. One group was given a high cholesterol diet (HCD) for 12 weeks to establish atherosclerosis and the control group normal diet (ND). Five rabbits from each group were then given intravenous water-based contrast media before being sacrificed. The entire length of aorta was dissected and submitted for histopathological examination and determination of tissue biomarkers α-SMA and MMP-9. RESULTS: Histopathological examination of the aorta including percentage of area covered by plaque and foam cell formation showed no significant difference in atheromatous plaque formation in both groups of HCD rabbits with or without intravenous contrast media injection (plaque: 55±41 vs. 63±15, p=0.731; foam cells: 124±83 vs. 171±55, p=0.325). Similarly, α-SMA and MMP-9 protein expression also showed no significant difference in both groups (α-SMA: 70±20 vs. 67±26, p=0.807; MMP-9: 60±12 vs. 57±17, p=0.785). CONCLUSION: Water-based contrast media used in PMCTA does not affect the morphology or the immunohistochemistry staining of SMA and MMP-9 in atherosclerotic plaques.

Imaging alternatives to colonoscopy: CT colonography and colon capsule. European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guideline - Update 2020.

1. ESGE/ESGAR recommend computed tomographic colonography (CTC) as the radiological examination of choice for the diagnosis of colorectal neoplasia. Strong recommendation, high quality evidence. ESGE/ESGAR do not recommend barium enema in this setting. Strong recommendation, high quality evidence.2. ESGE/ESGAR recommend CTC, preferably the same or next day, if colonoscopy is incomplete. The timing depends on an interdisciplinary decision including endoscopic and radiological factors. Strong recommendation, low quality evidence. ESGE/ESGAR suggests that, in centers with expertise in and availability of colon capsule endoscopy (CCE), CCE preferably the same or the next day may be considered if colonoscopy is incomplete. Weak recommendation, low quality evidence.3. When colonoscopy is contraindicated or not possible, ESGE/ESGAR recommend CTC as an acceptable and equally sensitive alternative for patients with alarm symptoms. Strong recommendation, high quality evidence. Because of lack of direct evidence, ESGE/ESGAR do not recommend CCE in this situation. Very low quality evidence. ESGE/ESGAR recommend CTC as an acceptable alternative to colonoscopy for patients with non-alarm symptoms. Strong recommendation, high quality evidence. In centers with availability, ESGE/ESGAR suggests that CCE may be considered in patients with non-alarm symptoms. Weak recommendation, low quality evidence.4. Where there is no organized fecal immunochemical test (FIT)-based population colorectal screening program, ESGE/ESGAR recommend CTC as an option for colorectal cancer screening, providing the screenee is adequately informed about test characteristics, benefits, and risks, and depending on local service- and patient-related factors. Strong recommendation, high quality evidence. ESGE/ESGAR do not suggest CCE as a first-line screening test for colorectal cancer. Weak recommendation, low quality evidence.5. ESGE/ESGAR recommend CTC in the case of a positive fecal occult blood test (FOBT) or FIT with incomplete or unfeasible colonoscopy, within organized population screening programs. Strong recommendation, moderate quality evidence. ESGE/ESGAR also suggest the use of CCE in this setting based on availability. Weak recommendation, moderate quality evidence.6. ESGE/ESGAR suggest CTC with intravenous contrast medium injection for surveillance after curative-intent resection of colorectal cancer only in patients in whom colonoscopy is contraindicated or unfeasible. Weak recommendation, low quality evidence. There is insufficient evidence to recommend CCE in this setting. Very low quality evidence.7. ESGE/ESGAR suggest CTC in patients with high risk polyps undergoing surveillance after polypectomy only when colonoscopy is unfeasible. Weak recommendation, low quality evidence. There is insufficient evidence to recommend CCE in post-polypectomy surveillance. Very low quality evidence.8. ESGE/ESGAR recommend against CTC in patients with acute colonic inflammation and in those who have recently undergone colorectal surgery, pending a multidisciplinary evaluation. Strong recommendation, low quality evidence.9. ESGE/ESGAR recommend referral for endoscopic polypectomy in patients with at least one polyp ≥6 mm detected at CTC or CCE. Follow-up CTC may be clinically considered for 6-9-mm CTC-detected lesions if patients do not undergo polypectomy because of patient choice, comorbidity, and/or low risk profile for advanced neoplasia. Strong recommendation, moderate quality evidence. Source and scope This is an update of the 2014-15 Guideline of the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR). It addresses the clinical indications for the use of imaging alternatives to standard colonoscopy. A targeted literature search was performed to evaluate the evidence supporting the use of computed tomographic colonography (CTC) or colon capsule endoscopy (CCE). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendations and the quality of evidence.

Imaging of facial neuritis using T2-weighted gradient-echo fast imaging employing steady-state acquisition after gadolinium injection.

MRI is the modality of choice for the imaging of facial neuritis. Previously, gadolinium-enhanced T1-weighted imaging of the petrous bone, then FLAIR sequences were thought to be most informative for acute facial neuritis imaging. The aim of this study is to evaluate the value of contrast-enhanced T2-weighted sequence for the diagnosis of acute facial neuritis and compare it to contrast-enhanced T1-weighted and FLAIR sequences. We included 50 patients with an acute unilateral idiopathic peripheral facial neuritis. An MRI (3T) with three sequences was performed (T1-weighted, T2-weighted and FLAIR), all acquired after intravenous contrast-media injection. The contrast-enhanced T2-weighted sequence appeared to be the most accurate one for the diagnosis of acute facial neuritis (Se 94%, Sp 100%, accuracy 98.2%, p < 0.001), with a pathological facial nerve strongly (grade 2-3) enhancing and a homogenous enhancement along the course of the entire facial nerve. Contrast-enhanced T1-weighted (Se 80%, Sp 100%, accuracy 94.1%) and FLAIR sequences (92%, Sp 88%, accuracy 90%, p < 0.001) showed lower accuracy. On T1-weighted sequence, a strong enhancement (blurred margins) of the canalicular segment was observed in 80% of the cases when it was never observed in normal nerves. A strong (= iso to hyperintense to the petrous fat signal) and diffuse (all segments) enhancement of the facial nerve on T2-weighted steady-state free precession sequence is a sensitive and specific sign for the diagnosis of acute idiopathic facial neuritis, and appears superior to T1WI and FLAIR sequences.

Air Bubbles in the Heart: A Case of Contrast Media Injection-Induced Venous Air Embolism

Venous air embolism (VAE) is more frequently recognized nowadays with the increased use of computed tomography (CT). It may be detected during or even after intravenous contrast media injection. A wide range of clinical manifestations exist, ranging from an incidental finding in a clinically asymptomatic patient to obstructive shock and circulatory failure. Those found incidentally are usually small and have no significant effect on circulatory physiology. Larger air emboli, however, may be potentially fatal, and therefore it is important to recognize such a phenomenon in the setting of intravenous contrast media injection.

Contrast-associated acute kidney injury in elderly; a mini-review on nursing prospectives

Contrast medium is used daily for accurate and effective diagnostic procedures. They are often necessary to provide an exact diagnosis and are almost safe and effective when used correctly. However contrast media can sometimes be life-threatening especially in elderly, since the elderly suffer from several problems. Aging is frequently accompanied by chronic diseases like chronic renal failure, comorbidity, frailty and disability. Therefore, it is important to know how reactions to contrast agents manifest and how to manage them immediately. Decreased kidney functions are sometimes seen after intravenous contrast media injection therefore radiologists should monitor all stages of the contrast injection. Accordingly, the medical team should have information on the complications, prevention and care of the patients under contrast media.

Dual-energy CT angiography in suspected pulmonary embolism: influence of injection protocols on image quality and perfused blood volume

To compare intravenous contrast material (CM) injection protocols for dual-energy CT pulmonary angiography (CTPA) in patients with suspected acute pulmonary embolism with regard to image quality and pulmonary perfused blood volume (PBV) values. A total of 198 studies performed with four CM injection protocols varying in CM volume and iodine delivery rates (IDR) were retrospectively included: (A) 60 ml at 5 ml/s (IDR = 1.75gI/s), (B) 50 ml at 5 ml/s (IDR = 1.75gI/s), (C) 50 ml at 4 ml/s (IDR = 1.40gI/s), (D) 40 ml at 3 ml/s (IDR = 1.05gI/s). Image quality and PBV values at different resolution settings were compared. Pulmonary arterial tract attenuation was highest for protocol A (397 ± 110 HU; p vs. B = 0.13; vs. C = 0.02; vs. D < 0.001). CTPA image quality of protocol A was rated superior compared to protocols B and D by reader 1 (p = 0.01; < 0.001), and superior to protocols B, C and D by reader 2 (p < 0.001; 0.02; < 0.001). Otherwise, there were no significant differences in CTPA quality ratings. Subjective iodine map ratings did not vary significantly between protocols A, B, and C. Both readers rated protocol D inferior to all other protocols (p < 0.05). PBV values did not vary significantly between protocols A and B at resolution settings of 1, 4 and 10 (p = 0.10; 0.10; 0.09), while otherwise PBV values displayed a decreasing trend from protocol A to D (p < 0.05). Higher CM volume and IDR are associated with superior CTPA and iodine map quality and higher absolute PBV values.