Iodine Allergy Research Articles

Chronic thromboembolic pulmonary hypertension and iodine allergy successfully treated using gadolinium contrast and pressure catheter.

Chronic thromboembolic pulmonary hypertension and iodine allergy successfully treated using gadolinium contrast and pressure catheter.

Imaging technology to assess tissue oxygen saturation of the gastric conduit in thoracic esophagectomy

ObjectiveThe objective of the study was to evaluate a novel imaging technology for assessing tissue oxygen saturation (StO2) in the gastric conduit during thoracic esophagectomy, comparing it to the traditional method of indocyanine green (ICG) fluorescence angiography, which has several limitations. MethodsThis prospective study included 60 patients with thoracic esophageal cancer undergoing thoracic esophagectomy, approved by the National Cancer Center Hospital’s institutional review board. A new videoscope system with oxygen saturation imaging (OXEI) mode was tested. Intraoperative StO2 and ICG measurements were taken at the tip of the gastric conduit, the demarcation line of visible perfusion, and the end of the right gastroepiploic artery. The study aimed to compare the correlation between StO2 and ICG values and evaluate the incidence of postoperative anastomotic leakage. ResultsOut of 60 patients, 57 were analyzed after excluding three for oncological reasons. Anastomotic leakage occurred in three patients. StO2 values decreased towards the tip of the conduit and were significantly lower at the tip compared to the demarcation line (P = 0.001). The mean StO2 at the anastomosis site was significantly lower in patients with leakage (P = 0.04). There was a negative correlation between StO2 and ICG values at the end of the right gastroepiploic artery (r = -0.361; P = 0.03). Two of the three patients with leakage had normal ICG values but low StO2 values and marked congestion. ConclusionStO2 imaging proved useful in determining the anastomotic site and addressed the limitations of the ICG method, which is contraindicated in patients with iodine allergy and subject to measurement biases. The OXEI method, being non-invasive and capable of real-time assessment, shows promise in predicting anastomotic leakage. Further prospective studies in larger, multi-center trials are planned to confirm these findings and evaluate the efficacy of OXEI compared to ICG.

P-313 Additional tubal flushing with ethiodized oil during transvaginal hydrolaparoscopy; feasibility and live birth rate, a pilot study in subfertile women

Abstract Study question Is tubal flushing with ethiodized oil during transvaginal hydrolaparoscopy (THL) feasible and what is the live birth rate within 6 months after THL? Summary answer Additional flushing with ethiodized oil during THL is feasible and safe with a live birth rate of 32.0% compared to 23.4% using solely water-based-contrast (p = 0.25). What is known already The use of ethiodized oil during hysterosalpingography (HSG), an alternative method to test tubal patency, has shown to have a positive effect on the live birth rate, compared to the use of water-based contrast (methylene blue). The benefit of THL over HSG as a tubal testing method is the possibility to also explore tubo-ovarian structures and the pouch of Douglas. Currently, only water-based media are used for tubal flushing during THL. Study design, size, duration A single-center cohort study at Máxima MC, the Netherlands, including 50 subfertile women who underwent THL and in whom there was at least unilateral tubal patency for methylene blue. Outcomes of interest included feasibility, safety and 6- months live birth rate. Our data were compared with a historical cohort of 111 subfertile women who underwent THL using solely water-based contrast (van Kessel MA. et al., 2021). Univariate – and multivariate logistic regression analysis were performed. Participants/materials, setting, methods Women with an iodine allergy and/or manifest thyroid dysfunction were excluded. Participants received additional tubal flushing with ethiodized oil (Lipiodol® Ultra Fluid). Main outcomes were appearance of oil and cell/mucus debris at the tubal fimbriae, pain scores (Visual Analogue Scale, VAS) and acceptability scores (0-10, completely unacceptable-acceptable). Secondary outcomes included; amount of ethiodized oil used, thyroid function four weeks afterwards, adverse events and live birth rate within 6 months after THL. Main results and the role of chance In 48 of the 50 THL procedures there was bilateral patency to methylene blue, ethiodized oil appeared from the tubal fimbriae bilateral in 77% (37/48), unilateral in 17% (8/48), while it did not appear in 6% (3/48). In two procedures there was unilateral patency to methylene blue. Ethiodized oil appeared unilateral in one and did not appear during the other THL. The amount of ethiodized oil used was 5 mL [3.4–6.3). The median reported pain scores on the VAS were 2.9 [IQR 1.0–5.0] after flushing with methylene blue and 3.0 [IQR 1.0–5.0] after ethiodized oil. The acceptability of the procedure was rated as 10 out of 10 [IQR 8–10]. Four weeks after the procedure 14% (6/42) had developed subclinical hypothyroidism, one woman had overt hypothyroidism (FT4 slightly decreased to 11.0 pmol/L, TSH 5.60 mU/L) and one woman had isolated hypothyroxinemia (FT4 11.0 pmol/L, TSH 3.40 mU/L). One adverse event, persistent bleeding at the trocar insertion site was reported, for which a diagnostic laparoscopy was performed. The live birth rate within 6 months after a THL was 32% (16/50), compared to 23% (26/111) in our historical cohort using solely water-based contrast (OR = 1.54, 95% CI 0.74–3.22, P = 0.25). Limitations, reasons for caution As this is a pilot study without a power analysis, the study is presumably underpowered to show an effect on the live birth rate. Also, the control group was historical. Wider implications of the findings By proving feasibility of using ethiodized oil during THL we encourage further research on its effect on pregnancy rates. Furthermore, the direct observation of tubal flushing with ethiodized oil during THL enables further investigation of the contrast characteristics, which are presumably responsible for its positive effect on live birth rate. Trial registration number NL8696

Real-time detection of gastrointestinal leaks via bismuth chelate-enhanced X-ray gastroenterography

Anastomotic leaks are among the most dreaded complications following gastrointestinal (GI) surgery, and contrast-enhanced X-ray gastroenterography is considered the preferred initial diagnostic method for GI leaks. However, from fundamental research to clinical practice, the only oral iodinated contrast agents currently available for GI leaks detection are facing several challenges, including low sensitivity, iodine allergy, and contraindications in patients with thyroid diseases. Herein, we propose a cinematic contrast-enhanced X-ray gastroenterography for the real-time detection of GI leaks with an iodine-free bismuth chelate (Bi-DTPA) for the first time. The Bi-DTPA, synthesized through a straightforward one-pot method, offers distinct advantages such as no need for purification, a nearly 100 % yield, large-scale production capability, and good biocompatibility. The remarkable X-ray attenuation properties of Bi-DTPA enable real-time dynamic visualization of whole GI tract under both X-ray gastroenterography and computed tomography (CT) imaging. More importantly, the leaky site and severity can be both clearly displayed during Bi-DTPA-enhanced gastroenterography in a rat model with esophageal leakage. The proposed movie-like Bi-DTPA-enhanced X-ray imaging approach presents a promising alternative to traditional GI radiography based on iodinated molecules. It demonstrates significant potential in addressing concerns related to iodine-associated adverse effects and offers an alternative method for visually detecting gastrointestinal leaks.

The Myth of “Iodine Allergy”

The Myth of “Iodine Allergy”

Effective local treatment of necrotizing fasciitis using a chlorine solution obtained by electrolysis

Introduction. Severe surgical wound infection as necrotizing fasciitis is one of the leading causes of death in the postoperative period. Large wounds affecting the skin and soft tissues are a particular problem, as such wounds are difficult to heal, especially in immunocompromised patients. Local treatment is important, and different antiseptics are in clinical use. Case outline. A 45-year-old woman with terminal kidney failure, with hypothyroidism and iodine allergy was admitted to the hospital with multiple abscess formation in abdominal wall. After first surgery necrotic fasciitis and sepsis were diagnosed. Complete parenteral therapy, including antibiotics, other supportive therapy and hemodialysis was performed. Successive debridement and local treatment with chlorine solution obtained by electrolysis as irrigation solution and wet wound dressing used daily lead to complete healing. Delayed wound closure was performed. She was discharged in good general condition, and the wound was healed completely. Conclusion. The application of a chlorine solution obtained by electrolysis (Aqualor H 200, Serbia) in a concentration of 0.2 mg/l is effective for local treatment of wounds by washing and applying wet dressing in the wound on skin and soft tissue, especially necrotizing fasciitis as wound with mixed bacterial infection.

Clinical Issues - December 2023.

Head lice Key words: lice, nit, hair, infestation, transmission. Patients with iodine and chlorhexidine allergies Key words: antiseptic, skin preparation, alcohol, chloroxylenol, soap. Storing sterile and unsterile supplies together Key words: storage, shelves, event-related sterility, package integrity, handling. Using indwelling urinary catheters during general surgery Key words: indwelling urinary catheter, Michigan Appropriate Perioperative (MAP) criteria, urinary retention, bladder scanner, routine use.

Gadolinium as a contrast agent for infusion sialograms in patients with iodine allergy.

To assess the adequacy of gadolinium in sialography as an alternative contrast agent for patients with iodine allergies. To directly compare images taken with gadolinium versus iodine-based contrast agents using the Iowa Sialography Classification System. Retrospective chart review was performed on patients undergoing sialography between February 2008 and July 2022. Patients with sialograms obtained with gadolinium were identified and matched to similar sialograms obtained with iodine-based contrast agent. Patients were matched based on duct location, duct side, and initial radiology findings. Blinded reevaluation of sialograms was performed first independently and then by consensus by two head and neck radiologists to evaluate overall image adequacy and grade using the Iowa Sialography Classification System. Four patients with six sialograms (one bilateral parotid and one parotid + submandibular) obtained with gadolinium were identified and reevaluated. Five patients with six sialograms (one bilateral parotid) obtained with iodine-based were matched to the gadolinium sialograms. The overall adequacy of images for gadolinium sialograms was graded at an average of 4.25 (4 = good and 5 = excellent); whereas, the overall adequacy of iodine-based sialograms was graded at an average of 5. Inter-observer variability was observed in three sialograms obtained with gadolinium (50%), while no interobserver variability was observed in sialograms obtained with iodine-based contrast agent. Gadolinium is an adequate alternative to use in sialography for patients with iodine allergies undergoing contemporary digital infusion sialography. Adverse reactions to iodine contrast agents are rare in sialography; however, the precautionary use of gadolinium is acceptable for the diagnostic and therapeutic benefits in sialography.Level of Evidence: IV.

Extrapolation of CT aortic annulus derived diameter/CT aortic annulus area from 2D echocardiography aortic annulus diameter in TAVR: not a reliable tool

Abstract Funding Acknowledgements Type of funding sources: None. Background Computed tomography (CT) aortic annulus area, CT area derived diameter and two-dimensional echocardiography (2D ECHO) diameters are used for valvular sizing in transcutaneous aortic valve replacement (TAVR). According to our previous study, 2D ECHO annulus diameter was smaller in comparison to CT derived diameter (22.6±2.9 vs 25.0±5.5mm, p = 0.013), but both CT aortic annulus area derived diameter/CT aortic annulus and 2D ECHO diameter predicted correct valve size selection with the same accuracy of 79–80%. However, CT requires radiation and iodine contrast administration, which might be the limitation in patients with chronic kidney disease or history of iodine allergy. Purpose To determine if 2D ECHO diameter can be used for reliable estimation of CT area derived diameter/CT aortic annulus area. Methods 139 consecutive patients with favourable outcome of Sapien XT/Sapien S3 TAVR (no more than mild aortic regurgitation, only one valve implanted) were included in the study. 2D ECHO diameter was measured from mid oesophageal three-chamber view (110–135°) just below the anatomical aortic valve annulus. CT aortic annulus was obtained as double oblique plane by manual multiplanar reconstruction of CT dataset, defined by three lowest attachment points of valvular leaflets. Aortic annulus area was measured by manual tracking of lumen contours, area derived diameter as 2*√(area/π). Linear regression analysis between pre-implant CT area derived diameter and 2D ECHO diameter was performed; extrapolated CT annulus area diameter and CT aortic annulus area [π*(d/2)2] were calculated from 2D ECHO diameter. Concordance of valve size selection based on extrapolated CT area derived diameter vs original CT area derived diameter and extrapolated CT aortic annulus area vs original CT aortic annulus area was determined on patients where CT aortic annulus area/annulus derived diameter were falling outside the overlap of the manufacturer recommended ranges for neighbouring valve sizes. Results Significant relationship between CT aera derived diameter and 2D ECHO diameter was found (r=0.720, p<0.001, Fig 1,2). Extrapolated CT area derived diameter would have led to inappropriate size selection in 33/100 more cases (undersizing in 16%, oversizing in 17%), similar to extrapolated aortic annulus area, where both undersizing and oversizing was observed in 18/106 (17%) more cases in comparison to original CT based parameters. Conclusion Extrapolation of CT aortic annulus area/area derived diameter from 2D ECHO diameter is not a reliable tool in valvular sizing for balloon expandable Sapien valve. In patients with chronic kidney disease or history of iodine allergy, three-dimensional (3D) ECHO aortic annulus assessment remains the only viable alternative tool.

Iodine Allergy and the Orthopaedic Patient.

Fraval, Andrew MD, FRACS1,a; Mont, Michael A. MD2; Parvizi, Javad MD, FRCS1 Author Information

Vaginal Preparation Prior to Planned Cesarean Delivery to Reduce Postpartum Endometritis: A Quality Improvement Study [ID: 1378331

INTRODUCTION: Infection prophylaxis is an important part of perioperative care. Studies have demonstrated that incorporation of pre-cesarean vaginal preparation reduces postoperative rates of endometritis in laboring patients or those with ruptured membranes. Our study aimed to identify whether vaginal preparation decreases the risk of postpartum endometritis among scheduled cesarean deliveries. METHODS: We retrospectively reviewed all pregnant people with scheduled cesarean deliveries in one urban, teaching hospital between April 2018 and November 2020. Deliveries were excluded if they were laboring, had ruptured membranes prior to surgery, had known iodine allergy, or had other intraoperative complications. Deliveries were divided into three groups based on vaginal preparation protocol implementation: preimplementation (April 2018 to March 2019), implementation (April 2019 to November 2019), and postimplementation (December 2019 to November 2020). Only deliveries in the preimplementation versus postimplementation group were compared given implementation learning curve. Descriptive and inferential statistics were computed; χ2 or Fisher’s exact test was used to assess differences in rates of endometritis or other postpartum complications. RESULTS: Overall, 320 scheduled cesarean deliveries were included (N=162 preimplementation; N=158 postimplementation). Rates of endometritis was not different between groups (1.2% versus 2.5% postimplementation; P=.44). Similarly, postpartum complication rates for fever (1.2% versus 3.8% postimplementation, P=.17), wound infection (3.7% versus 3.2% postimplementation, P=.79), sepsis (0% versus 0.6% postimplementation, P=.49), and 30-day readmission unrelated to preeclampsia (3.7% versus 3.3% postimplementation, P=.12) were not different between groups. CONCLUSION: While there was no reduction in postpartum endometritis in patients undergoing planned cesarean delivery, universal implementation may still be a reasonable intervention given its low cost and known benefit in laboring patients or those with ruptured membranes.

Perioperative anaphylaxis to povidone-iodine in breast prosthesis surgery: a case report

The authors describe an unusual case of anaphylaxis to PVP-I resulting in cardiorespiratory collapse and dispel some recurrent misconceptions around allergies to PVP-I and so-called ‘iodine allergy’.

Prophylaxis of Ocular Infection in the Setting of Intraocular Surgery: Implications for Clinical Practice and Risk Management.

In this review we discuss the role of intraocular surgery preoperative prophylaxis. The correct choice of antimicrobial drug is variable in each surgical setting, according to the available strengths of evidence, the anatomical district involved, and the type of procedure. In the ophthalmic surgical field, there has been a progressive shift from antibiotic formulations, which are known to cause antibiotic resistance, to a new class of antiseptic compounds, which proved to be effective not only against bacteria, but also against fungi, protozoa, and viruses. Among these, povidone-iodine (PVI) is a water-soluble polymer that can form a complex with iodine, and the perioperative application of PVI 5-10% eye drop for 3min is the gold standard for infection prophylaxis. A new formulation of 0.6% PVI eye drop is a new option for infection prophylaxis in the days before surgery. Chlorhexidine is a biguanide compound, which is a valid alternative with a good safety and efficacy profile and is the antiseptic of choice in patients with iodine allergy. New compounds that are currently being studied include polyhexamethylene biguanide (PHMB), picloxydine, ozone, hypochlorous acid (HOCl), and Biosecur. PHMB is a biguanide polymer that was found to be more effective than PVI in invitro studies for reducing microorganisms and extending the duration of antisepsis, but to date, there are no formulations available on the market for preoperative ocular surgery in which it is present as main ingredient. Ozone is a molecule with oxidizing effect, which showed interesting preliminary results but is not effective against virus, Staphylococcusaureus and Candidaalbicans. HOCl has a natural bactericidal propriety but its applicability to prophylaxis of ocular infection in the setting of ocular surgery is not established. Biosecur is a non-toxic organic alcohol-free compound that exhibited bactericidal and fungicidal effect versus all common microorganisms and is currently available as an ocular spray.

A Deep Learning Approach to Visualize Aortic Aneurysm Morphology Without the Use of Intravenous Contrast Agents.

Intravenous contrast agents are routinely used in CT imaging to enable the visualization of intravascular pathology, such as with abdominal aortic aneurysms. However, the injection is contraindicated in patients with iodine allergy and is associated with renal complications. In this study, we investigate if the raw data acquired from a noncontrast CT image contains sufficient information to differentiate blood and other soft tissue components. A deep learning pipeline underpinned by generative adversarial networks was developed to simulate contrast enhanced CTA images using noncontrast CTs. Two generative models (cycle- and conditional) are trained with paired noncontrast and contrast enhanced CTs from seventy-five patients (total of 11,243 pairs of images) with abdominal aortic aneurysms in a 3-fold cross-validation approach with a training/testing split of 50:25 patients. Subsequently, models were evaluated on an independent validation cohort of 200 patients (total of 29,468 pairs of images). Both deep learning generative models are able to perform this image transformation task with the Cycle-generative adversarial network (GAN) model outperforming the Conditional-GAN model as measured by aneurysm lumen segmentation accuracy (Cycle-GAN: 86.1% ± 12.2% vs Con-GAN: 85.7% ± 10.4%) and thrombus spatial morphology classification accuracy (Cycle-GAN: 93.5% vs Con-GAN: 85.7%). This pipeline implements deep learning methods to generate CTAs from noncontrast images, without the need of contrast injection, that bear strong concordance to the ground truth and enable the assessment ofimportant clinical metrics. Our pipeline is poised to disrupt clinical pathways requiring intravenous contrast.

PS-R07-7: USE OF GADOLINIUM CONTRAST MEDIUM ENABLES ADRENAL VEIN SAMPLING IN A FLORID PRIMARY ALDOSTERONISM PATIENT WITH IODINE ALLERGY

Case: A 35-year-old woman was allergic to iodine contrast medium and was diagnosed with primary aldosteronism (PA) based on functional confirmatory tests. She was suspected to have unilateral PA because of marked hypertension, spontaneous hypokalemia, high plasma aldosterone, reduced plasma renin activity, and a right hypodense adrenal tumor. She wanted to become pregnant and requested adrenalectomy instead of medical treatment with mineralocorticoid receptor antagonists. Localization of PA by adrenal vein sampling (AVS) was necessary, but angiography with iodine contrast medium was not possible because of her allergy. AVS was performed using gadolinium contrast agent (gadoterate meglumine) instead of iodine, in combination with computed tomography angiography (CTA) because the American College of Radiology manual does not recommend prior steroid administration for high-risk patients who have already exhibited adverse reactions to iodine contrast medium. In AVS, before and after adrenocorticotropic hormone (ACTH) loading, 12 blood samples were drawn from the right adrenal vein, left adrenal central vein, left adrenal common duct, left and right renal veins, and the lower inferior vena cava with only 5 mL of gadolinium medium. There were no complications during AVS. Examination revealed an elevated aldosterone/cortisol ratio on the right side, lateralized ratio of 7.4, and contralateral ratio of 0.76; the patient was diagnosed with right unilateral PA. She underwent right adrenalectomy and showed improvements in aldosterone level from 312.4 pg/mL to 83.0 pg/mL, potassium from 3.0 mEq/L to 3.9 mEq/L, and systolic blood pressure from 138 mmHg to 117 mmHg. She is currently off her medications. Conclusion: In PA patients with iodine allergy, AVS can be performed safely and precisely using gadolinium contrast combined with CTA.

A model established for predicting natural pregnancy possibility based on the imaging characteristics of 4-dimensional hysterosalpingo-contrast sonography.

The incidence of infertility is increasing, more than 30% of them having related abnormal tubal patency. Four-dimensional (4D) hysterosalpingo-contrast sonography (HyCoSy) overcomes the shortcomings of 3D HyCoSy in the diagnosis of tubal patency, showing high specificity and accuracy. In addition, 4D HyCoSy discards iodine allergy and X-ray radiation and possesses easy-operating, contributing to good acceptance in clinical practice. However, there is no research to explore the imaging standards related to the possibility of natural pregnancy after 4D HyCoSy. If a predictive model of postoperative natural pregnancy was established using the analysis of clinical data combined with imaging characteristics of 4D HyCoSy of patients with tubal factor infertility, clinical decision-making can be wisely guided in the future. This study aims to establish a predictive model of natural pregnancy after 4D HyCoSy based on clinical data and imaging characteristics of patients with tubal factor in fertility. A retrospective study was conducted for patients who were diagnosed with tubal factor infertility in Hunan Guangxiu Hospital from February 2017 to May 2018. The patients ought to possess complete 4D HyCoSy imaging data and at least one-side-unobstructed fallopian tube. General clinical data and imaging data were collected. Pregnancy outcome was followed up till 3 months after 4D HyCoSy. According to pregnancy outcome, patients were divided into a pregnancy group and a non-pregnancy group. Binary logistic regression was used to analyze the correlation between various variables and natural pregnancy after 4D HyCoSy. The variables with significant difference (P<0.05) in single-factor logistic regression were included in the natural pregnancy probability prediction model. The classification accuracy was further verified with 10-fold cross-validation. A total of 1 085 patients with clinically suspected tubal factor infertility who met the requirements and followed the doctors' prescription were collected. Clinical characteristics (age and duration of infertility) and 4D HyCoSy imaging characteristics (thickness of endometrium from the 3rd to the 7th day after the end of menstruation, visualization of the left fallopian tube, the diffusion of contrast agent around the left ovary, and the diffusion of contrast agent around the right ovary) were independent predictors for natural pregnancy 3 months after 4D HyCoSy. A natural pregnancy probability prediction model was established with the area under the curve (AUC) verified by the 10-fold cross-validation all greater than 0.75, and the best AUC was 0.868. The Q value obtained by the prediction model was the probability of natural pregnancy, and the cutoff value was 0.5. When the Q value was greater than 0.5, it was recommended to attempt natural pregnancy for 3 months, and when the Q value was less than 0.5, in vitro fertilization was adviced. A predictive model for the evaluating probability of natural pregnancy in women with tubal factor infertility after 4D HyCoSy is successfully established based on the analysis for clinical data and imaging characteristics. This model shows a great potential in assisting clinical decision making.

CHARACTERIZING OVERLAPPING RADIOCONTRAST MEDIA, SHELLFISH, AND IODINE ALLERGIES

<h3>Introduction</h3> Patients with documented radiocontrast media (RCM) hypersensitivity reactions may require allergy testing or pretreatment prior to imaging with RCM, which may delay studies and is not without side effects. An RCM allergy is often incorrectly associated with iodine and shellfish allergies, but the frequency of this is not well characterized. <h3>Methods</h3> This is a retrospective chart review of patients within the electronic medical record (EMR). Terms used to indicate RCM, iodine, and shellfish allergies were obtained and the EMR was searched in October 2021 for patients with one or more qualifying allergies. Demographic information and allergy data was obtained for these patients. <h3>Results</h3> 21745 patients were identified: 14968 female, 6775 male, and 2 other. Among these patents, there were 24333 qualifying allergies: 6752 RCM (31.05%), 7398 iodine (34.02%), and 10183 shellfish (46.83%). 19338 patients (88.93%) had one qualifying allergy, 2226 patients (10.24%) had two (840 contrast and iodine, 363 contrast and shellfish). 181 patients (0.83%) had all 3. Contrast reactions were: 581 anaphylaxis (8.6%), 1961 cutaneous (29%), 183 gastrointestinal (2.71%), 187 respiratory (2.77%), 3578 other/unknown (52.99%). <h3>Conclusion</h3> The majority of patients with documented RCM allergies had cutaneous or unspecified reactions, with 17.82% of these patients having overlapping contrast and iodine (12.44%) or shellfish (5.38%) allergies. It is unclear whether this represents true IgE mediated allergic reactions. More work is needed to standardize reaction documentation to identify true hypersensitivity reactions versus adverse reactions or side effects and to prevent unnecessary testing.

Development and evaluation of a radiomics model of resting 13N-ammonia positron emission tomography myocardial perfusion imaging to predict coronary artery stenosis in patients with suspected coronary heart disease.

Coronary angiography (CAG) is usually performed in patients with coronary heart disease (CHD) to evaluate the coronary artery stenosis. However, patients with iodine allergy and renal dysfunction are not suitable for CAG. We try to develop a radiomics machine learning model based on rest 13N-ammonia (13N-NH3) positron emission tomography (PET) myocardial perfusion imaging (MPI) to predict coronary stenosis. Eighty-four patients were included with the inclusion criteria: adult patients; suspected CHD; resting MPI and CAG were performed; and complete data. Coronary artery stenosis >75% were considered to be significant stenosis. Patients were randomly divided into a training group and a testing group with a ratio of 1:1. Myocardial blood flow (MBF), perfusion defect extent (EXT), total perfusion deficit (TPD), and summed rest score (SRS) were obtained. Myocardial static images of the left ventricular (LV) coronary segments were segmented, and radiomics features were extracted. In the training set, the conventional parameter (MPI model) and radiomics (Rad model) models were constructed using the machine learning method and were combined to construct a nomogram. The models' performance was evaluated by area under the curve (AUC), accuracy, sensitivity, specificity, decision analysis curve (DCA), and calibration curves. Testing and subgroup analysis were performed. MPI model was composed of MBF and EXT, and Rad model was composed of 12 radiomics features. In the training set, the AUC/accuracy/sensitivity/specificity of the MPI model, Rad model, and the nomogram were 0.795/0.778/0.937/0.511, 0.912/0.825/0.760/0.936 and 0.911/0.865/0.924/0.766 respectively. In the testing set, the AUC/accuracy/sensitivity/specificity of the MPI model, Rad model, and the nomogram were 0.798/0.722/0.659/0.841, 0.887/0.810/0.744/0.932 and 0.900/0.849/0.854/0.841 respectively. The AUC of Rad model and nomogram were significantly higher than that of MPI model. The DCA curve also showed that the clinical net benefit of the Rad model and nomogram was similar but greater than that of MPI model. The calibration curve showed good agreement between the observed and predicted values of the Rad model. In the subgroup analysis of Rad model, there was no significant difference in AUC between subgroups. The Rad model is more accurate than the MPI model in predicting coronary stenosis. This noninvasive technique could help improve risk stratification and had good generalization ability.

The use of CO2 to create an optical window during intravascular optical coherence tomography in a patient with an allergic reaction to iodine contrast

A necessary condition for obtaining a high-quality image with optical coherence tomography (OCT) is the displacement of blood from the visualized segment of the vessel to provide a transparent medium between the vascular wall and the photo detector. Traditionally, liquid iodine-containing contrast is used for this, which can be dangerous in patients with iodine allergy or renal insufficiency. We present a clinical case of successful OCT using CO2 in a patient with anaphylactic reaction to iodine-containing contrast. OCT was performed to monitor the safety of radiofrequency renal denervation. CO2 was injected as standard into a guide catheter located in the renal artery. With the help of CO2, it was possible to effectively displace blood from the renal artery and obtain high-quality OCT images of the vascular wall microstructure.

Evaluating pharmacists' knowledge, attitude, and practices toward amiodarone cross-reactivity with iodine: a cross-sectional pilot study.

IntroductionIodine is a vital mineral of the human body that acts by maintaining the health of the thyroid gland. Research has shown that iodine-rich food allergy (i.e., seafood allergy) is not caused by iodine itself; instead, it is caused by other proteins including tropomyosin and parvalbumin in shellfish and fish, respectively. Amiodarone is a commonly used antiarrhythmic agent containing a significant amount of iodine.ObjectiveThis study’s objective was to assess pharmacists’ knowledge, attitude, and practices toward the misconception of iodine allergy and the cross-reactivity with amiodarone.MethodsIn February 2020, a cross-sectional study was conducted by sending out an online survey to three pharmaceutical organizations (Saudi Pharmaceutical Society, Kuwait Pharmaceutical Association, and Oman Pharmaceutical Society). Additionally, an electronic questionnaire was administered to pharmacists attending the Dubai International Pharmaceuticals and Technologies Conference and Exhibition 2020 (DUPHAT). Chi-square or Fisher’s exact test, when appropriate, were used to compare categorical variables. The statistical analyses were carried out using SPSS software.ResultsData were collected from 66 respondents. However, only 61 (92.4%) were included in the final analysis following the exclusion of incomplete responses. The mean age of participants was 35 ± 8.48 years. The majority of participants did not have the Board of Pharmacy Specialties Certification (54.1%). Moreover, (41%) of participants licensed as pharmacists with more than 10 years of initial pharmacy licensure. Forty-three (70.5%) of participants had the misconception that iodine allergy should be considered before amiodarone administration, 20/32 (62.5%) of whom considered iodine allergy alone thought that premedication with corticosteroids and/or antihistamines is necessary. Concerning iodine allergy and amiodarone use, there was no significant difference in knowledge between the pharmacists who have board certification and those who did not.ConclusionPharmacists’ misconception concerning iodine allergy and cross-reactivity with amiodarone was evident. Implementation of educational programs targeting pharmacists is necessary to correct these misconceptions.