Iodinated Contrast Research Articles

Risks of Iodine Excess.

Iodine is a micronutrient that is required for thyroid hormone synthesis. The iodide cycle in thyroid hormone synthesis consists of a series of transport, oxidation, organification, and binding/coupling steps in thyroid follicular cells. Common sources of iodine include the consumption of an iodine-rich diet or iodine fortified foods, the administration of amiodarone, iodine-containing supplements, or iodinated contrast media, and other miscellaneous sources. Methods to assess population iodine status include the measurement of urinary iodine concentrations, blood thyroglobulin levels, prevalence of elevated neonatal TSH levels, and thyroid volume. Although excessive iodine intake or exposure is generally well tolerated, an acute iodine load may result in thyroid dysfunction (hypothyroidism or hyperthyroidism) in certain susceptible individuals due to the failure to escape from the Wolff-Chaikoff effect and to the Jod-Basedow phenomenon, respectively. In this review, we discuss the associations between excessive iodine intake or exposure, with particular focus on iodinated contrast media as a common source of excess iodine in healthcare settings, and risks of incident thyroid dysfunction. We also summarize the risks of iodine excess in vulnerable populations and review current guidelines regarding the screening and monitoring of iodinated contrast-induced thyroid dysfunction. Finally, we discuss the long-term potential nonthyroidal health risks associated with iodine excess and suggest the need for more data to define safe upper limits for iodine intake, particularly in high-risk populations.

Virtual noncontrast images reveal gouty tophi in contrast-enhanced dual-energy CT: a phantom study

BackgroundDual-energy computed tomography (DECT) is useful for detecting gouty tophi. While iodinated contrast media (ICM) might enhance the detection of monosodium urate crystals (MSU), higher iodine concentrations hamper their detection. Calculating virtual noncontrast (VNC) images might improve the detection of enhancing tophi. The aim of this study was to evaluate MSU detection with VNC images from DECT acquisitions in phantoms, compared against the results with standard DECT reconstructions.MethodsA grid-like and a biophantom with 25 suspensions containing different concentrations of ICM (0 to 2%) and MSU (0 to 50%) were scanned with sequential single-source DECT using an ascending order of tube current time product at 80 kVp (16.5–220 mAs) and 135 kVp (2.75–19.25 mAs). VNC images were equivalently reconstructed at 80 and 135 kVp. Two-material decomposition analysis for MSU detection was applied for the VNC and conventional CT images. MSU detection and attenuation values were compared in both modalities.ResultsFor 0, 0.25, 0.5, 1, and 2% ICM, the average detection indices (DIs) for all MSU concentrations (35–50%) with VNC postprocessing were respectively 25.2, 36.6, 30.9, 38.9, and 45.8% for the grid phantom scans and 11.7, 9.4, 5.5, 24.0, and 25.0% for the porcine phantom scans. In the conventional CT image group, the average DIs were respectively 35.4, 54.3, 45.4, 1.0, and 0.0% for the grid phantom and 19.4, 17.9, 3.0, 0.0, and 0.0% for the porcine phantom scans.ConclusionsVNC effectively reduces the suppression of information caused by high concentrations of ICM, thereby improving the detection of MSU.Relevance statementContrast-enhanced DECT alone may suffice for diagnosing gout without a native acquisition.Key points• Highly concentrated contrast media hinders monosodium urate crystal detection in CT imaging• Virtual noncontrast imaging redetects monosodium urate crystals in high-iodinated contrast media concentrations.• Contrast-enhanced DECT alone may suffice for diagnosing gout without a native acquisition.Graphical

The Effect of Iodinated Contrast Media Sensitivity on the Prognosis of Patients with STEMI

Background and Objectives: Iodinated Contrast Media (ICM) is used daily in many imaging departments worldwide. The main risk associated with ICM is hypersensitivity. When a severe hypersensitivity reaction is not properly managed and treated swiftly, it may be fatal. Currently, there is no data to demonstrate how ICM sensitivity affects the prognosis of cardiac patients, especially those diagnosed with ST elevation myocardial infarction (STEMI), in whom urgent coronary angiography is indicated. This study aimed to identify and characterize this relationship. Materials and Methods: We included patients hospitalized with STEMI between 2016 and 2019 from the National Inpatient Sample. The population was compared based on ICM sensitivity status, sensitive vs. non-sensitive. The primary endpoint was in-hospital mortality, with additional endpoints: length of stay and in-hospital complications. Results: The study included 664,620 STEMI patients, of whom 4905 (0.7%) were diagnosed with ICM sensitivity. ICM-sensitive patients were older, more often white, females, and had more comorbidities and cardiovascular risk factors. Both groups show similarities in management but are slightly less probable to undergo PCI or CABG. Multivariable logistic regression models found that the ICM-sensitive population had similar odds of in-hospital mortality (OR: 1.02, 95% CI: 0.89–1.16) and MACCE (OR: 1.05, 95% CI: 0.95–1.16), and less major bleeding (OR: 0.73, 95% CI: 0.60–0.87). Conclusions: Our study found that ICM sensitivity status was not a significant factor for worse prognosis in patients hospitalized with STEMI.

Successful Embolization of a Direct Carotid Cavernous Fistula under Gadolinium-Based Angiography.

Endovascular neurointervention is typically performed with iodinated contrast medium (ICM) under fluoroscopy. However, some patients may be contraindicated to such procedures based on their sensitivity to ICM. In this report, we describe a case of successful coil embolization of a direct carotid cavernous fistula using angiography with gadolinium-based contrast agents in a patient with severe allergic reaction to ICM. The clinical decision-making for this patient was further complicated by comorbidities of renal impairment, drug allergies, and previously severe gastrointestinal bleeding.

Assessment of Biological Damage Induced during Multidetector Computed Tomography (MDCT) Examination.

Computed tomography (CT) is known for its non-invasiveness, fast procedure, and also for providing detailed diagnostic information to physicians. It also utilises low-dose-rate ionising radiation (X-rays) as a source for imaging. Multidetector computed tomography (MDCT) is an advanced system that uses iodinated contrast media for more accurate diagnostic results. Studies suggest using these contrasts will lead to greater radiation adsorption with significant DNA damage. No studies have been taken comparing the physical dose with the biological effect. The present study sheds light on the same by assessing the biological effect of CT with and without contrast intervention. The present study is timebound; thus, 21 participants attending for CT thorax and abdomen with no history of any cancer were included. The same participants underwent both pre-contrast and post-contrast studies. The blood sample was taken before the procedure and used as a control. Physical parameters like DLP and CTDI obtained from the instrument were compared with the MN frequency obtained (CBMN Assay). The study showed a significant increase (p-value < 0.05) in the Physical and MN frequency in the Post-Contrast group compared to the pre-contrast group. Although a positive correlation was observed between pre and post-contrast groups, the results were not found to be statistically significant (p-value < 0.05). The study confirms increased physical dose and MN frequency upon contrast intervention. This study recommends the judicial use of MDCT in disease diagnostics.

Gadolinium-Based Contrast Agents: Rationale for Use in Patients with Iodine Contrast or Shellfish Allergy?

Gadolinium-Based Contrast Agents: Rationale for Use in Patients with Iodine Contrast or Shellfish Allergy?

Incidence of contrast-associated acute kidney injury: a prospective cohort.

Contrast-associated acute kidney injury (CA-AKI) is a deterioration of kidney function that occurs after the administration of a iodinated contrast medium (ICM). Most studies that defined this phenomenon used older ICMs that were more prone of causing CA-AKI. In the past decade, several articles questioned the true incidence of CA-AKI. However, there is still a paucity of a data about the safety of newer ICM. To assess the incidence of CA-AKI in hospitalized patients that were exposed to computed tomography (CT) with and without ICM. Prospective cohort study with 1003 patients who underwent CT in a tertiary hospital from December 2020 through March 2021. All inpatients aged > 18 years who had a CT scan during this period were screened for the study. CA-AKI was defined as a relative increase of serum creatinine of ≥ 50% from baseline or an absolute increase of ≥ 0.3 mg/dL within 18 to 48 hours after the CT. Chi-squared test, Kruskal-Wallis test, and linear regression model with restricted cubic splines were used for statistical analyses. The incidence of CA-AKI was 10.1% in the ICM-exposed group and 12.4% in the control group when using the absolute increase criterion. The creatinine variation from baseline was not significantly different between groups. After adjusting for baseline factors, contrast use did not correlate with worse renal function. The rate of CA-AKI is very low, if present at all, with newer ICMs, and excessive caution regarding contrast use is probably unwarranted.

Ultrahigh-Resolution K-Edge Imaging of Coronary Arteries With Prototype Deep-Silicon Photon-Counting CT: Initial Results in Phantoms.

Background Photon-counting CT (PCCT) represents a recent advancement in CT, offering improved spatial resolution and spectral separability. By using multiple adjustable energy bins, PCCT enables K-edge imaging, allowing mixed contrast agent distinction. Deep-silicon is a new type of photon-counting detector with different characteristics compared with cadmium photon-counting detectors. Purpose To evaluate the performance of a prototype deep-Si PCCT scanner and compare it with that of a state-of-the-art dual-energy energy-integrating detector (EID) scanner in imaging coronary artery plaques enhanced with iodine and K-edge contrast agents. Materials and Methods A series of 10 three-dimensional-printed inserts (diameter, 3.5 mm) was prepared, and materials mimicking soft and calcified plaques were added to simulate stenosed coronary arteries. Inserts filled with an iodine- or gadolinium-based contrast agent (GBCA) were scanned. Virtual monoenergetic images (VMIs) and iodine maps were generated using two- and eight-energy bin data from EID CT and PCCT, respectively. Gadolinium maps were calculated for PCCT. The CT numbers of VMIs and iodine maps were compared. Spatial resolution and blooming artifacts were compared on the 70-keV VMIs in plaque-free and calcified coronary arteries. Results No evidence of a significant difference in the CT number of 70-keV images was found except in inserts containing GBCAs. In the absence of a GBCA, excellent (r > 0.99) agreement for iodine was found. PCCT could quantify the GBCA within 0.2 mg Gd/mL ± 0.8 accuracy of the ground truth, whereas EID CT failed to detect the GBCA. Lumen measurements were more accurate for PCCT than for EID CT, with mean errors of 167 versus 442 µm (P < .001) compared with the 3.5-mm ground truth. Conclusion Deep-Si PCCT demonstrated good accuracy in iodine quantification and could accurately decompose mixtures of two contrast agents. Its improved spatial resolution resulted in sharper images with blooming artifacts reduced by 50% compared with a state-of-the-art dual-energy EID CT scanner. © RSNA, 2024.

Cardiovascular Imaging, Climate Change, and Environmental Sustainability.

Environmental exposures including poor air quality and extreme temperatures are exacerbated by climate change and are associated with adverse cardiovascular outcomes. Concomitantly, the delivery of health care generates substantial atmospheric greenhouse gas (GHG) emissions contributing to the climate crisis. Therefore, cardiac imaging teams must be aware not only of the adverse cardiovascular health effects of climate change, but also the downstream environmental ramifications of cardiovascular imaging. The purpose of this review is to highlight the impact of climate change on cardiovascular health, discuss the environmental impact of cardiovascular imaging, and describe opportunities to improve environmental sustainability of cardiac MRI, cardiac CT, echocardiography, cardiac nuclear imaging, and invasive cardiovascular imaging. Overarching strategies to improve environmental sustainability in cardiovascular imaging include prioritizing imaging tests with lower GHG emissions when more than one test is appropriate, reducing low-value imaging, and turning equipment off when not in use. Modality-specific opportunities include focused MRI protocols and low-field-strength applications, iodine contrast media recycling programs in cardiac CT, judicious use of US-enhancing agents in echocardiography, improved radiopharmaceutical procurement and waste management in nuclear cardiology, and use of reusable supplies in interventional suites. Finally, future directions and research are highlighted, including life cycle assessments over the lifespan of cardiac imaging equipment and the impact of artificial intelligence tools. Keywords: Heart, Safety, Sustainability, Cardiovascular Imaging Supplemental material is available for this article. © RSNA, 2024.

Diagnostic efficacy of dual energy CT in differentiating intracerebral hemorrhage from iodinated contrast material staining

Diagnostic efficacy of dual energy CT in differentiating intracerebral hemorrhage from iodinated contrast material staining

Prevention of Hypersensitivity Reaction to Iodinated Contrast Media during Vascular Access Procedure

Prevention of Hypersensitivity Reaction to Iodinated Contrast Media during Vascular Access Procedure

Impact of ACIST CVi contrast delivery system on iodinated contrast media administration and waste.

The COVID-19 pandemic led to disruptions in iodinated contrast media (ICM) production and produced a global product shortage in the spring of 2022. The ACIST CVi system is an automated contrast injector system approved by the FDA for multi-patient dosing of ICM from a single container. A transition from the traditional manifold system for contrast injection to the ACIST CVi automated injector system in our cardiac angiographic labs during the COVID-19 pandemic led to reductions in contrast waste and cost while limiting patient exposure to ICM.

Atrial fibrillation cryoablation guided by pressure waveform: a prospective multicentre registry

Abstract Background Cryoballoon ablation (CA) procedures require optimal occlusion of the pulmonary veins (PV), which is conventionally evaluated by iodine contrast injection through the catheter tip. This technique has some weaknesses such as risk of allergic reactions, nephrotoxicity, requirement of fluoroscopy (sometimes at high doses), requirement of a second operator, among others. PV pressure waveform assessment is an alternative method for confirming occlusion, however, multicentre assessment of periprocedural efficacy and safety is lacking. Purpose To describe the intra-procedural performance and safety of routine pressure-based CA. Methods In this independent prospective multicentre observational study, baseline and procedure data from consecutive pressure-guided CB ablations were collected. Operators were not required to have experience in pressure-guided CA for participating in the registry. They were asked to classify the pressure waveform curves into type 1 (presence of "a-wave" and/or symmetric "v-wave", meaning incomplete PV occlusion) and type 2 (absence of "a-wave" and asymmetric "v-wave", meaning complete PV occlusion), Figure 1. The primary endpoint was PV isolation in all veins without use of contrast. Procedure performance and adverse events were also analyzed. Results A total of 150 patients (mean age: 61 ± 10 y.) with paroxysmal (62%) or persistent AF (38%) were included and underwent pressure-guided CA in 9 centres from Spain. Complete PV isolation was achieved in 148 patients (98%). The operators switched to contrast use in 14 cases (9%), mainly to double check the occlusion. Total procedure and fluoroscopy time were 97 ± 39 and 19 ± 10 min respectively. There were 7 (4.7%) procedure related adverse events: 4 phrenic nerve palsy (3 of them were transient), 1 transient coronary ST elevation (before ablation), 1 gastroparesis and 1 femoral pseudoaneurysm. Most relevant results are summarized in Figure 2. Conclusion In this multicentre and multi-brand assessment, CA guided by pressure waveforms provided outstanding procedural outcomes, which were equivalent to those reported with the conventional approach. All operators could easily obtain and identify the waveform without a specific learning curve, avoiding the use of iodine contrast in most cases. The long-term efficacy of this approach will be presented in future analyses.Pressure waveforms types in cryoablationProcedural data

#1983 In vitro iohexol adsorption in cartridges with mesoporous styrene-divinylbenzene sorbent

Abstract Background and Aims Patients with pre-existing chronic kidney disease (CKD) present the highest risk of developing contrast-associated acute kidney injury (CA-AKI). Iodinated contrast agents such as iohexol (molecular weight 821 Da) don't bind to proteins and are easily removed by hemodialysis filters. However, the session time necessary to remove approximately 75% of the injected iohexol load is around six hours. Due to lack of evidence, current guidelines do not recommend to start hemodialysis in CKD patients in conservative management after the administration of iodinated contrast media to prevent or mitigate CA-AKI. Still, a strong rationale supports the removal of iodinated contrast media because of its nephrotoxicity. In this study, we aimed to investigate the capability of a mesoporous styrene-divinylbenzene sorbent to bind iohexol in vitro. Method We used 1,000 mL of saline solution spiked with 40 mL of iohexol 350 mg/mL in a closed-loop configuration. Iohexol concentration was 14 mg/mL. The amount of the iodinated radiocontrast was proportional to the amount used in complex percutaneous coronary interventions (worst-case scenario), around 200 mL, in a 70 kg person with an estimated blood volume of 5,000 mL. The solution circulated through a HA380 mini-module cartridge filled with 75g of mesoporous styrene-divinylbenzene sorbent beads at 250 ml/min. The experiment was carried out twice with the same setup. Samples were collected at eight-time points (0, 5, 10, 15, 20, 30, 40, and 60 minutes) from the reservoir to measure iohexol concentration. The analysis of the samples was carried out in duplicate. The removal ratio (RR) was calculated considering the initial concentration (C(0)) and the variation of the concentration during the experiment (C(t), where t is the time point), as follows: $RR( \% ) = \frac{{C( 0 ) - C( t )}}{{C( 0 )}}100$ Results In the first experiment, the removal ratios after 5, 30, and 60 minutes were 23.4%, 45.8%, and 52.9%, respectively on average. In the second experiment, the reduction ratios after 5, 30, and 60 minutes were 23.4%, 45.5%, and 53.1%, respectively on average. After 30 minutes, the adsorption curved plateaued, indicating cartridge saturation (Fig. 2). Conclusion This in vitro model demonstrated that HA380 sorbent cartridge was effective in removing iohexol. The use of hemoadsorption as a strategy to remove iodinated contrast media warrants further investigation because of its clinical potential to reduce the exposure to nephrotoxic contrast agents and CA-AKI.

A deep learning approach for virtual contrast enhancement in Contrast Enhanced Spectral Mammography

Contrast Enhanced Spectral Mammography (CESM) is a dual-energy mammographic imaging technique that first requires intravenously administering an iodinated contrast medium. Then, it collects both a low-energy image, comparable to standard mammography, and a high-energy image. The two scans are combined to get a recombined image showing contrast enhancement. Despite CESM diagnostic advantages for breast cancer diagnosis, the use of contrast medium can cause side effects, and CESM also beams patients with a higher radiation dose compared to standard mammography. To address these limitations, this work proposes using deep generative models for virtual contrast enhancement on CESM, aiming to make CESM contrast-free and reduce the radiation dose. Our deep networks, consisting of an autoencoder and two Generative Adversarial Networks, the Pix2Pix, and the CycleGAN, generate synthetic recombined images solely from low-energy images. We perform an extensive quantitative and qualitative analysis of the model’s performance, also exploiting radiologists’ assessments, on a novel CESM dataset that includes 1138 images. As a further contribution to this work, we make the dataset publicly available. The results show that CycleGAN is the most promising deep network to generate synthetic recombined images, highlighting the potential of artificial intelligence techniques for virtual contrast enhancement in this field.

#2921 The SOFA score: predictive factor of nephrotoxicity post injection of iodized PDC in the emergency room

Abstract Background and Aims Nephrotoxicity following injection of iodinated contrast media is the leading cause of iatrogenic acute renal failure. Its incidence is variable taking into account the study population as well as associated factors. The aim: To study the contribution of the SOFA score in the prediction of nephrotoxicity post injection of iodized PDCs in septic patients. Method This was a prospective, single-center study over a six-month period. Patients aged over 14 years and having undergone an injection of iodinated contrast products were included. Nephropathy in this context is defined by an elevation in plasma creatinine of more than 25% within 48 to 72 hours following injection and in the absence of other etiologies. Results During the study period, 135 patients were collected with a mean age of 46 ± 18 years and range of 16 to 97 years. The gender ratio was 3.2 with a male predominance. Hypertension and diabetes were the most noted comorbidities (20.7%, 20%). Clinical examination revealed polypnea in 26% of cases, desaturation in 11.8%, tachycardia (27%) and oliguria (5.2%). Fourteen patients had an altered state of consciousness with coma in 10.4% of cases. Twenty-one patients (15.6%) were febrile on admission. The incidence of nephropathy post injection of iodized PDCs was 15.6%. 111 patients (82.8%) benefited from per-procedure hydration. Emergency mortality was 4.4% (n=6). The SOFA score was calculated in 24 patients with a median score of three. Nineteen patients (14.1%) had a score ranging from two to six, which predicts an intra-hospital mortality risk of 10%. Four patients (2.9%) had a score between 7 and 9, which reflects a risk of death of 15 to 20%. In univariate analysis, the SOFA score was calculated in six patients with nephrotoxicity and in 18 patients who did not develop nephrotoxicity. A score between seven and nine was significantly associated with the risk of developing nephrotoxicity (14.3% vs 0.9%) with p=0.012 and ORb=19.2, 95% CI [1.8-196.8]. Conclusion The incidence of post-iodized PDC injection nephropathy was high in emergency rooms. Among the independent factors associated with nephrotoxicity, the SOFA score was found to be.

#2994 Nephrotoxicity post injection of iodized PDC in patients with renal failure in the emergency room

Abstract Background and Aims Nephropathy following injection of iodinated contrast media (PDC) is the leading cause of iatrogenic acute renal failure. Several associated factors have been identified, including renal function before the procedure. Objective To study the incidence of nephrotoxicity post venous-injection of iodinated PDC in patients with impaired renal function. Method This was a prospective, descriptive, single-center study over a six-month period. Patients aged over 14 years and having undergone an injection of iodinated contrast products for diagnostic or therapeutic purposes were included. We excluded patients with stage IV renal insufficiency (Cl ≤ 29 ml/min) with or without indication for extra-renal purification. Nephropathy in this context was defined by an elevation in baseline plasma creatinine of more than 25% in the 48 to 72 hours following injection. Results During the study period, 135 patients were collected with a mean age of 46 ± 18 years and range of 16 to 97 years. The gender ratio was 3.2 with a male predominance. Thirty-two patients had impaired renal function on admission, of which seven patients (5.2%) were known to have chronic renal failure and twenty-five patients (18.5%) had impaired renal function discovered on admission. The mean renal clearance was 90.9 ± 36.3 ml/min with extremes ranging from 30 ml/min to 176 ml/min. More than half of the patients had normal renal function (Stage G1 according to the KDIGO 2022 classification) (n = 79, 58.5%). The incidence of nephropathy post venous-injection of iodized PDCs was 15.6%. 111 patients (82.8%) benefited from per-procedure hydration protocol. In univariate analysis, chronic renal failure or discovered on admission was associated with the risk of worsening renal function with a statistically significant difference, p respectively at 0.007 and 0.009. Furthermore, the correlation between the worsening of renal function as a function of initial plasma creatinine showed that initial plasma creatinine was higher in patients who developed iodinated contrast nephropathy with a statistically significant difference, p = 0.005, a sensitivity of 57% and a specificity of 78%. ROC curve analysis showed an AUC of 0.691; 95% CI [0.567-0.815], with a discriminant Cut off of plasma creatinine at 90.5 µmol/l. Conclusion The incidence of post-iodized PDC injection nephropathy was high in emergency room. Among the independent associated factors identified, chronic renal insufficiency or discovered on admission which requires special precautions, especially through optimal hydration.

#1119 Iodine contrast does not contribute to impaired kidney function or need for dialysis

Abstract Background and Aims Imaging diagnostics play a crucial role in the management of patients with acute and critical conditions or suspected underlying disease like infections or malignancy. These examinations are often enhanced by intravenous iodine-based contrast, to improve the imaging quality and the diagnostic accuracy. For long, there has been a conception that these contrast materials are nephrotoxic, but the last decade has provided a significant quantity of modern studies suggesting that this is not the case. The present study evaluates if earlier contrast exposure has contributed to progress in CKD and the need of initiating dialysis treatment in patients who were in maintenance dialysis treatment at the Västerås hospital at the time of inclusion. Method All patients admitted to the dialysis ward in Västerås the 1st of January 2022 were included and copies of all radiology surveys and all lab values from the electronical records for this study population for the last 10 years were extracted to check for contrast exposure. For some patients, this occurred when they were already on maintenance dialysis treatment, others were pre-dialytic at the time or had not yet developed any kidney impairment. For every contrast exposure, we checked the previous creatinine and the earliest creatinine after the examination to check for acute kidney injury, AKI, as defined by KDIGO. As a secondary outcome, we investigated the frequency of examinations where contrast otherwise would be indicated, but was withhold, due to fear of contrast induced AKI. Results In total, 83 patients were included in this study, and among them there were 121 cases of contrast exposure. There were no events of AKI when eGFR was &amp;gt; 30 ml/min. In the subgroup of patients with eGFR &amp;lt; 30 ml/min, but not in dialysis at the time of the examination, there were only 25 cases of contrast exposure, and only one event of AKI, but this was considered largely due to overhydration and decompensated heart failure and resolved with proper treatment. Among the patients already in dialysis, there were 65 contrast exposures, and no event where any subjects lost their residual kidney function due to contrast induced AKI. In the meantime, there were 249 examinations where contrast material was withheld due to low eGFR, even though it normally would be indicated by the reason of the examination. Conclusion There was none significant event of potential contrast induced AKI among the patients in our study and no patient had any lasting impact on their kidney function from contrast exposure. Contrast exposure does not seem to be a common contributing cause of progressing to end stage renal disease. This is well in line with previous, modern observation studies, suggesting that the risk of contrast induced nephropathy is overrated or possible even a myth. Perhaps even more importantly, contrast enhancement was often inadequately withheld, even though it normally would be necessary to accurately make the diagnosis that was the purpose of ordering the study. Poor imaging quality limits the ability to make correct diagnoses, resulting in substandard treatment for the CKD-population.

Subpleural pulmonary nodule marking with patent blue V dye prior to surgical resection.

Subpleural located pulmonary nodules are perioperatively invisible to the surgeon. Their precise identification is conventionally possible by palpation, but often at the cost of performing a thoracotomy. The aim of the study was to evaluate the success rate and feasibility of the pre-operative CT-guided marking subpleural localized nodule using a mixture of Patent Blue V and an iodine contrast agent prior to the extra-anatomical video-assisted thoracoscopic surgery (VATS) resection in patients for whom the primary anatomical resection in terms of segmentectomy or lobectomy was not indicated. The data of consecutive patients with pulmonary nodules located ≤ 30 mm from the parietal pleura, who were indicated for VATS extra-anatomical resection between 2017 to 2023, were retrospectively reviewed and analyzed. All patients indicated for VATS resection underwent color marking of the area with the pulmonary lesion under CT-guided control immediately before the surgery. The primary outcome was the marking success. Morphological lesion characteristics, time from marking to the surgery, procedure related complications, final histology findings and 30day mortality were analyzed. Additionally, we assessed the association of the successful marking and the patient's smoking history. A total of 62 lesions were marked. The successful marking was observed in 56/62 (90.3%) patients. The median time from the lesion marking to the beginning of surgery was 75.0 (IQR 65.0-85.0) minutes. The procedure related pneumothorax was observed in 6 (9.7%) patients, intraparenchymal hematoma in 1 (1.6%) patient. No statistically significant association of the depth of the subpleural lesion's location, occurrence of complications or time from the marking to surgery and the successful marking was observed. The 30day mortality was zero. No association of smoking and successful marking was observed. The method of marking the subpleural pulmonary lesions under CT-guided control with a mixture of Patent Blue V and iodine contrast agent is a safe and effective method with minimal complications. It provides surgeons the precise visualization of the affected pulmonary parenchyma before the planned extra-anatomical VATS resection.

Stability testing of iomeprol and iopamidol formulations subjected to X-ray radiation

IntroductionExposure of iodinated contrast media (ICM) to X-rays is not uncommon, as contrast media are often stored in close proximity to radiological equipment. However, the interaction between X-rays and ICM is not widely investigated in literature. The present study aims to investigate the chemical stability of iomeprol and iopamidol, two commercial iodinated ICM commonly used in diagnostic imaging, under X-rays exposure. MethodsDifferent formulations of iopamidol and iomeprol (iodine concentration 9 to 400 mgI/mL, volume 50–500 mL) were exposed to three different conditions of X-ray irradiation: i) 1 month storage in CT room (≈5–15 mGy); (ii) low-dose protocol (≈10 mGy); (ii) stressed protocol (≈100 mGy). Unexposed and exposed solutions were characterized by high-performance liquid chromatography in terms of concentration of active pharmaceutical ingredient (API), iodine species and by products. In addition, appearance and colour of the solutions were inspected and pH measured. ResultsAPI concentrations, appearance, colour and pH of the exposed formulations remained unaffected by X-rays. Measured concentrations of iodine species and by products were observed well within the acceptability criteria, i.e. values turned out to be lower than specifications limits established by the manufacturer, considering both release and shelf-life values. ConclusionsUp to 100 mGy X-ray exposure did not induce any alteration of iomeprol and iopamidol formulation, nor a detectable increase in the concentration of iodine species or by-products. Implications for practiceOur study strengthens the hypothesis that ICM are stable under X-rays exposure up to 100 mGy.