Contrast-enhanced Examinations Research Articles

Risk of acute kidney injury following repeated contrast exposure in trauma patients.

This study investigates the risk of contrast-associated acute kidney injury (CA-AKI) in trauma patients, focusing on the impact of cumulative contrast medium doses. A retrospective review was conducted at a level 1 trauma center (2019-2021). The study included patients who underwent intravascular contrast-enhanced examinations for torso trauma within 7 days post-injury. The total contrast medium volume within 7 days was calculated. Multivariate logistic regression (MLR) identified AKI risk factors. Among the 264 patients, 7.2% (19/264) developed AKI, with 3.4% (9/264) classified as KDIGO stage 3. Approximately 42.8% of patients underwent at least two contrast-enhanced examinations. The mean total contrast medium given was 129.5mL (range 80-410ml). Multiple logistic regression (MLR) analysis identified four independent risk factors for AKI: diabetes mellitus, initial eGFR < 30, use of inotropic agents, and contrast medium exposure. The odds ratio of AKI increased by 2.92 (95% CI 1.30-6.53) for every 100ml increase in contrast dose. The contrast volume exposure only plays an important role in severe trauma patients (ISS ≥ 25). Moreover, when correlated with eGFR, the contrast medium exposure volume demonstrated better predictive ability for AKI with a best cut-off value of Contrast volume to eGFR ratio > 1.86. While repetitive contrast-enhanced examinations are sometimes inevitable, they do come with costs. The CA-AKI risk increases as the amount of contrast medium accumulates in trauma patients who require repetitive examinations.

Contrast Media-driven Anthropogenic Gadolinium: Knowns and Unknowns.

Gadolinium-based contrast agents (GBCAs) have augmented the capabilities of MRI, which has led to their widespread and increasing use in radiology practice. GBCAs are introduced into the environment through disposal of unused product and elimination after intravenous injection, both primarily via liquid dispersion into the environment. This human introduction of gadolinium into the environment, referred to as anthropogenic gadolinium, is associated with the detection of gadolinium in water systems, raising concerns for potential adverse impact and prompting certain mitigation actions. This article summarizes the existing knowledge and problem scope, conveys the relevant underlying chemical principles of chelate dissociation, and offers an inferred perspective that the magnitude of the problem is most unlikely to cause human harm. The merits and limitations regarding possible mitigation tactics, such as collecting urine after GBCA administration, use of lower-dose high-relaxivity macrocyclic GBCAs, and the option for virtual contrast-enhanced examinations, will be discussed. Finally, the potential for monitoring gadolinium uptake in bone will be presented, and recommendations for future research will be offered. © RSNA, 2024 See also the article by Ibrahim et al in this issue. See also the article by McKee et al in this issue.

CT Urology에서 가돌리늄 조영제 제거를 위한 이중에너지 CT의 Virtual Non-Contrast 기술의 평가

Residual gadolinium contrast agents in the urinary tract following MRI contrast-enhanced examinations often presents as elevated Hounsfield Unit (HU) values on CT scans, impeding the efficacy of CT urology procedures. This study aims to explore the feasibility of addressing this challenge through the application of the Dual-Energy Computed Tomography (DECT) Virtual Non-Contrast (VNC) technique across various energy levels. HU values of residual gadolinium contrast agent in the renal pelvis and ureter were measured in patients who underwent MRI contrast-enhanced examinations followed by non-contrast CT chest examinations. Subsequently, gadolinium contrast agent mixtures, such as Max, Mean, and Min Mixtures, were created and scanned together with normal saline using DECT at various energy levels. Additionally, an iodine mixture and a virtual stone representing urolithiasis were fabricated and evaluated. The results demonstrated a significant reduction in contrast enhancement of gadolinium contrast agent with DECT VNC at 70 kV and Sn150 kV. The Min Mixture closely resembled normal saline in both HU and Contrast-to-Noise Ratio (CNR), facilitating the differentiation between iodine contrast agent and virtual urolithiasis. Therefore, utilizing DECT VNC after a 1-hour and 30-minute interval following MRI contrast-enhanced examinations effectively eliminates gadolinium contrast agents, improving the efficacy of CT Urology imaging procedures.

Outpatient Renal Function Screening Before Contrast-Enhanced CT Examinations.

Intravascular administration of iodinated contrast media can cause contrast-induced acute kidney injury, especially in patients with an estimated glomerular filtration rate (eGFR) less than 30 mL/min/1.73 m². The American College of Radiology (ACR) and the European Society of Urogenital Radiology (ESUR) guidelines recommend renal function screening based on medical history, but their effectiveness has been under-evaluated. This retrospective study included 2,560 consecutive adult outpatients without eGFR measurements within 180 days before contrast-enhanced computed tomography (CT) at a single tertiary hospital from July through September 2023. On the day of CT, they underwent eGFR tests and 1.1% had an eGFR < 30 mL/min/1.73 m², preferentially with histories of gout and renal disease. According to the ACR and ESUR strategies, 16.9% and 38.8% of all study participants were positive, respectively, identifying 92.6% and 96.3% of patients with renal insufficiency. Both strategies demonstrated high negative predictive values. These results support selective renal function screening before contrast-enhanced examinations.

Antireflux laparoscopic intervention

To study the safety and efficacy of laparoscopic fundoplication and hiatal hernia repair for gastroesophageal reflux disease following hiatal hernia. We retrospectively analyzed 56 patients with gastroesophageal reflux disease and hiatal hernia .They underwent laparoscopic fundoplication and hiatal hernia repair between January 2020 and January 2023. All surgeries were successful without conversion to open surgery. Surgery time was 56-180 min (mean 68.4±3.6), blood loss 30-200 ml (mean 40.3±5.6). No mortality and severe complications occurred. All patients were followed-up for 6-24 months. The GERD-Q and De Meester scores were significantly lower after 6 months compared to baseline values (p <0.05), and resting pressure was lower. Tone of lower esophageal sphincter was significantly higher compared to preoperative level (p <0.05). In 1-2 years after surgery, symptoms completely disappeared in 48 patients and significantly improved in 6 patients. Two patients had no improvement. Contrast-enhanced examination found no recurrent hiatal hernia and digestive tract obstruction. Aparoscopic fundoplication and hiatal hernia repair is safe and effective for gastroesophageal reflux disease with hiatal hernia.

Influence of Body Mass Index and Abdominal Circumference on Radiation Dose During Abdominopelvic Computed Tomography

Background: Contrast-enhanced examinations of the abdomen region have a greater radiation exposure due to the multiphase abdominal computed tomography (CT) protocols. The use of automatic tube current modulation is known to reduce radiation dose and maintain or improve image quality for abdominal CT. However, using automatic tube current modulation can increase radiation dose for individuals with a larger body habitus. Objectives: The study aimed to assess the influence of body mass index and abdominal circumference on the effective dose for routinely performed contrast-enhanced abdomen and pelvis scans. Methods: A total of 160 subjects referred for routine CT abdomen and pelvis were included in the study and categorised into three groups according to their body mass index (BMI) [underweight: &lt;18.5 kg/m2, normal: 18.5-24.9 kg/m2, overweight: 25-29.9 kg/m2 and obese: (≥30 kg/m2]. All the scans were performed on a 128 MDCT scanner by Philips. The effective dose was calculated from the dose length product using region-specific conversion factors. Results: The effective dose was found to be 21.47 ± 2 mSv for the underweight group, 22.75± 2.3 mSv for the normal group, 25.02 ± 2.8 for the overweight group, and 29.7 ± 6.7 mSv for the obese group. Conclusion: The study reported a 32.39 % increase in effective dose for obese patients. The study also reported a significant increase in effective dose as BMI and abdominal circumference increased.

Mesentero-axial gastric volvulus treated with laparoscopic gastropexy: a case report

BackgroundMesentero-axial gastric volvulus (MAGV) is an uncommon subtype of gastric volvulus (GV). However, reports of such cases in adult patients are very rare. We present an unusual case of idiopathic MAGV in an old woman.Case presentationAn 84-year-old woman was referred to the emergency department for vomiting and abdominal pain. An abdominal computed tomography scan revealed a mesentero-axial gastric volvulus, which could be corrected endoscopically, and the symptoms were relieved. Contrast-enhanced examination was performed before the elective surgery to confirm the presence of short-axis dorsal 180-degree volvulus. The patient underwent laparoscopic surgery on a wait-and-watch basis. After releasing the torsion, the stomach returned to normal position. The gastric fornix was sutured to the left diaphragm and the gastric body and antrum were sutured to the abdominal wall using non-absorbable thread. Symptoms did not flare after the surgery.ConclusionsWe experienced a rare case of adult MAGV presenting with incomplete obstruction. Laparoscopic gastropexy is useful when gastric decompression is achieved.

Efficacy of diffusion weighted imaging in sacroiliac joint MRI in children.

Because of the immature bone marrow signal in children, assessment of the sacroiliac joint is more difficult than in adults. Aim of this study is to evaluate the efficacy of diffusion-weighted imaging (DWI) in sacroiliac joint magnetic resonance imaging (MRI). Sacroiliac joint MRI, including DWI sequences, were evaluated by two pediatric radiologists in 54 patients with sacroiliitis and 85 completely normal controls. In MRI evaluation, subchondral bone marrow edema and contrast enhancement in the sacroiliac joints were considered as active sacroiliitis. Apparent diffusion coefficient (ADC) measurements were made in six areas from each sacroiliac joint. A total of 1668 fields were evaluated retrospectively without their diagnosis being known. When the postcontrast T1W series were referenced, the sensitivity, specificity, positive predictive value, and negative predictive value of short time inversion recovery (STIR) images in the diagnosis of sacroiliitis were 88%, 92%, 83% and 94% respectively, compared to contrast-enhanced images. False positive results in STIR images were observed secondary to the flaring signal in the immature bone marrow. ADC measurements obtained from diffusion-weighted images were recorded in all patients and healthy groups. The ADC values were 1.35x10-3 mm2/s (SD: 0.21) in the areas of sacroiliitis, 0.44x10-3 mm2/s (SD: 0.71) in the normal bone marrow and 0.72x10-3 mm2/s (SD: 0.76) in the immature bone marrow areas. Although STIR studies are an effective sequence in the diagnosis of sacroiliitis, they cause false positive results in immature bone marrow in children in inexperienced hands. DWI is an objective method that prevents errors in the assessment of sacroiliitis by means of ADC measurements in the immature skeleton. In addition, it is a short and effective MRI series that makes important contributions to the diagnosis without the need for contrast-enhanced examinations in children.

COMPUTED TOMOGRAPHY FINDINGS OF INTRACRANIAL CALCIFICATIONS

Objective&#x0D; In this study, the anatomical localization and&#x0D; distribution of intracranial calcifications detected on&#x0D; brain computed tomography (CT) were determined&#x0D; and their relationship with age and gender was&#x0D; investigated.&#x0D; Material and Method&#x0D; Images of 887 patients who underwent brain CT&#x0D; examinations for various reasons between March&#x0D; 2010 and May 2013 were analyzed. Images of 124&#x0D; patients were excluded from the study because of&#x0D; contrast-enhanced examination, bleeding, trauma,&#x0D; hydrocephalus, and image distortion. Seven hundred&#x0D; sixty three patients whose non-contrasted brain CT&#x0D; images were analyzed were divided into age groups&#x0D; according to decades. The pineal gland, choroid&#x0D; plexus, habenula, basal ganglia, tentorium cerebelli,&#x0D; falx cerebri, dural and arachnoid granulation,&#x0D; petroclinoid ligament, arterial wall, orbital, dystrophic&#x0D; and tumoral calcifications were evaluated. The&#x0D; distribution of intracranial calcifications according to&#x0D; age groups and gender were examined.&#x0D; Results&#x0D; Of the patients included in the study, 382 (50.1%)&#x0D; were female and 381 (49.9%) were male. Intracranial&#x0D; calcification was detected in 672 (88.1%) of the patients.&#x0D; The choroid plexus (78.2%) calcifications were most&#x0D; common, followed by habenula (62.4%), pineal gland&#x0D; (55.3%), arterial wall (31.2%), petroclinoid ligament&#x0D; (28.7%), and falx cerebri (20.7%). Calcifications of&#x0D; dural and arachnoid granulation (7.5%), basal ganglia&#x0D; (6.3%), tentorium cerebelli (2.9%), tumoral (1.2%)&#x0D; and orbital (0.5%) were detected less frequently,&#x0D; while dystrophic calcifications (0.4%) were the least&#x0D; common. A statistically significant difference was&#x0D; found in the distribution of calcifications according&#x0D; to age groups, in calcifications located in the pineal&#x0D; gland, choroid plexus, habenula, basal ganglia,&#x0D; tentorium cerebelli, falx cerebri, dural and arachnoid&#x0D; granulation, petroclinoid ligament and arterial wall. A&#x0D; statistically significant difference was found in choroid&#x0D; plexus, habenula, dural and arachnoid granulation&#x0D; and petroclinoid ligament calcifications in distribution&#x0D; according to gender.&#x0D; Conclusion&#x0D; Intracranial calcifications are most frequently detected&#x0D; in the choroid plexus, habenula and pineal gland,&#x0D; while dystrophic calcifications are seen the least.&#x0D; The incidence of intracranial calcifications generally&#x0D; increases from the age of 10. Tentorium cerebelli and&#x0D; dural and arachnoid granulation calcifications are&#x0D; more common in female.

Contrast-Enhanced 3D Spin Echo T1-Weighted Sequence Outperforms 3D Gradient Echo T1-Weighted Sequence for the Detection of Multiple Sclerosis Lesions on 3.0 T Brain MRI.

Using reliable contrast-enhanced T1 sequences is crucial to detect enhancing brain lesions for multiple sclerosis (MS) at the time of diagnosis and over follow-up. Contrast-enhanced 3D gradient-recalled echo (GRE) T1-weighted imaging (WI) and 3D turbo spin echo (TSE) T1-WI are both available for clinical practice and have never been compared within the context of this diagnosis. The aim of this study was to compare contrast-enhanced 3D GRE T1-WI and 3D TSE T1-WI for the detection of enhancing lesions in the brains of MS patients. This single-center prospective study enrolled patients with MS who underwent a 3.0 T brain MRI from August 2017 to April 2021 for follow-up. Contrast-enhanced 3D GRE T1-WI and 3D TSE T1-WI were acquired in randomized order. Two independent radiologists blinded to all data reported all contrast-enhanced lesions in each sequence. Their readings were compared with a reference standard established by a third expert neuroradiologist. Interobserver agreement, contrast ratio, and contrast-to-noise ratio were calculated for both sequences. A total of 158 MS patients were included (mean age, 40 ± 11 years; 95 women). Significantly more patients had at least 1 contrast-enhanced lesion on 3D TSE T1-WI than on 3D GRE T1-WI for both readers (61/158 [38.6%] vs 48/158 [30.4%] and 60/158 [38.6%] vs 47/158 [29.7%], P < 0.001). Significantly more contrast-enhanced lesions per patient were detected on 3D TSE T1-WI (mean 2.47 vs 1.56 and 2.56 vs 1.39, respectively, P < 0.001). Interobserver agreement was excellent for both sequences, κ = 0.96 (confidence interval [CI], 0.91-1.00) for 3D TSE T1-WI and 0.92 (CI, 0.86-0.99) for 3D GRE T1-WI. Contrast ratio and contrast-to-noise ratio were significantly higher on 3D TSE T1-WI (0.84 vs 0.53, P < 0.001, and 87.9 vs 57.8, P = 0.03, respectively). At 3.0 T, contrast-enhanced 3D TSE-T1-WI supports the detection of significantly more enhancing lesions than 3D GRE T1-WI and should therefore be used for MS patients requiring contrast-enhanced examination.

Dose estimation in abdominal CT scans using CT-Exposoftware

The application of ionizing radiation in diagnostic medicine has increased worldwide in the last decades. Computed Tomography (CT) is the main radiological procedure that contributes to the increase of the collective dose in the population. The aim of this study was to estimate the doses received by patients undergoing CT scans in a public hospital in Santa Catarina - Brazil, employing data from the DICOM header and utilizing the CT-Expo V. 2.7 software. The data were selected from 45 abdominal CT scans, performed consisted of two series: pre-contrast and one post-contrast intravenous, of adult patients performed in December 2020 in a public hospital located in Santa Catarina - Brazil. The spreadsheets with the data extracted from the DICOM headers were provided by the Santa Catarina Telemedicine System (STT). The effective dose and organ doses were calculated by CTDIvol and DLP values using the software. Overall, the organs that showed the higher equivalent doses were kidneys (19.5 mSv), spleen (18.5 mSv), stomach (18.9 mSv), and liver (18.1 mSv). The estimated effective doses were 7.31 and 8.41 mSv, for non-contrast and contrast-enhanced examinations. The use of software such as CT-Expo can support the estimation of effective doses received by patients through the information extracted from the DICOM header. The presented methodology can be a useful tool to retrospectively estimate the doses in CT services in Brazil.

Two nomograms based on radiomics models using triphasic CT for differentiation of adrenal lipid-poor benign lesions and metastases in a cancer population: an exploratory study.

To investigate the effectiveness of CT-based radiomics nomograms in differentiating adrenal lipid-poor benign lesions and metastases in a cancer population. This retrospective study enrolled 178 patients with cancer history from three medical centres categorised as those with adrenal lipid-poor benign lesions or metastases. Patients were divided into training, validation, and external testing cohorts. Radiomics features were extracted from triphasic CT images (unenhanced, arterial, and venous) to establish three single-phase models and one triphasic radiomics model using logistic regression. Unenhanced and triphasic nomograms were established by incorporating significant clinico-radiological factors and radscores. The models were evaluated by the receiver operating characteristic curve, Delong's test, calibration curve, and decision curve. Lesion side, diameter, and enhancement ratio resulted as independent factors and were selected into nomograms. The areas under the curves (AUCs) of unenhanced and triphasic radiomics models in validation (0.878, 0.914, p = 0.381) and external testing cohorts (0.900, 0.893, p = 0.882) were similar and higher than arterial and venous models (validation: 0.842, 0.765; testing: 0.814, 0.806). Unenhanced and triphasic nomograms yielded similar AUCs in validation (0.903, 0.906, p = 0.955) and testing cohorts (0.928, 0.946, p = 0.528). The calibration curves showed good agreement and decision curves indicated satisfactory clinical benefits. Unenhanced and triphasic CT-based radiomics nomograms resulted as a useful tool to differentiate adrenal lipid-poor benign lesions from metastases in a cancer population. They exhibited similar predictive efficacies, indicating that enhanced examinations could be avoided in special populations. • All four radiomics models and two nomograms using triphasic CT images exhibited favourable performances in three cohorts to characterise the cancer population's adrenal benign lesions and metastases. • Unenhanced and triphasic radiomics models had similar predictive performances, outperforming arterial and venous models. • Unenhanced and triphasic nomograms also exhibited similar efficacies and good clinical benefits, indicating that contrast-enhanced examinations could be avoided when identifying adrenal benign lesions and metastases.

Heterotaxy polysplenia syndrome presenting with bleeding from the greater curvature of stomach: a case report

BackgroundThe “heterotaxy syndrome” also called “situs ambiguus” is a rare condition in which the internal organs of the chest and abdomen are abnormally arranged. This syndrome is usually associated with a spectrum of health-related conditions involving birth defects in organs like the heart, spleen, liver, lungs and others.Case presentationWe present a case of a 29-year-old male who came with an episode of massive upper gastrointestinal bleeding. On arrival he was vitally unstable and after resuscitation underwent a contrast-enhanced CT scan examination. The CT scan identified the features of heterotaxy syndrome with left isomerism and an abnormal blush from the branch of splenic artery supplying the greater curvature of the stomach. Embolization of the splenic artery branches was performed with the help of gel foam. No abnormal blush was identified post-embolization. Later on, in his hospital stay the patient went into pulse less electrical activity and died.ConclusionUpper gastrointestinal bleed in the patients with heterotaxy syndrome is a rare presentation of a rare condition. Our case highlights the importance of diagnostic and interventional radiology in diagnosing such patients and identifying the site of bleed especially where endoscopic visualization is not possible and managing the bleeding efficiently.

Short-, Mid-, and Long-term Strategies to Manage the Shortage of Iohexol.

The recent iohexol shortage has precipitated disruptions in a pharmaceutical supply chain critical to radiologic imaging and has impacted global availability of iodinated contrast media (ICM). The shortage has created a national crisis in radiology departments, curtailing their ability to provide health care to patients who need contrast-enhanced examinations. Radiology departments are familiar with crisis management after more than 2 years of clinical and operational disruptions associated with the COVID-19 pandemic. The iohexol and subsequent ICM shortage has short-term (weeks), midterm (months), and long-term (years) implications. The purpose of this report is to provide strategies for dealing with the shortage in the near term and to discuss long-term issues and potential solutions to supply chain problems impacting radiology departments.

The Evaluation of Hepatocellular Carcinoma with Biphasic Contrast Enhanced Spiral CT Scan

Background: Hepatocellular Carcinoma (HCC) is the most common malignant neoplasm of the liver worldwide. Liver cancer ranks third among all cancer deaths in Bangladesh as the clinical presentation is non-specific, the modern imaging modalities can play an important role in the diagnosis of HCC and the radiologist is often the first to suggest the correct diagnosis. With the advent of multi-detector spiral CT, detection and characterization of HCC has markedly improved. Multi-detector spiral CT with its increased spatial and temporal resolution allows multiple perfusion phases of liver to be acquired.Multi-detector biphasic spiral CT techniques have been increasingly promising with respect to accurate preoperative diagnosis and assessment of the extent of HCC. This study was carried out to evaluate the role of biphasic contrast-enhanced spiral CT including Hepatic Arterial Phase (HAP) imaging with Portal Venous Phase (PVP) imaging, in the detection and characterization of HCC.&#x0D; Methods: The study included 35 patients (M=31, F=4) with histopathologically proven HCC. Age range was between 21-75 years (mean=51) by following consecutive patients in whom HCC was diagnosed or suspected either by raised serum a (alpha)-fetoprotein level or byultrasound imaging.&#x0D; Results: Biphasic contrast-enhanced examination in these 35 patients could reveal a total of 65 lesions, out of which 48% were unifocal and 46% were multifocal HCCs. On HAP imaging 92% lesions were detected. (hyper attenuating = 56, hypo attenuating = 4) while on PVP imaging delectability was only 51% (hyper attenuating=2, hypo attenuating=30). Hence delectability was significantly superior in HAP as compared to PVP imaging (p &lt;0.0001, 95% CI 25.2-54.7). In 49% tumor was visible only on HAP images. Venous invasion was present in 11 patients (31%).&#x0D; Conclusion: Biphasic contrast enhanced spiral CT is a useful method in detection and characterization of HCC.&#x0D; Sir Salimullah Med Coll J 2022; 30: 61-66

The differential diagnosis algorithm of ovarian tumors in reproductive patients: a prospective study

Aim. The aim of the study was to evaluate the efficiency of different methods of preoperative diagnostics and to develop an algorithm for examining patients of reproductive age with ovarian tumors.&#x0D; Materials and methods. The study included 100 patients operated in the gynecological and oncogynecological departments of Pletnev State Clinical Hospital (Moscow) in the period from Sep 2019 to Dec 2020. The inclusion criteria were reproductive age (1840 years); unilateral/bilateral nature of ovarian lesion; ovarian tumor existing for at least 3 months and confirmed by the data of instrumental research methods; the size of the pathological formation of the ovary according to instrumental examination 30 mm; normal/elevated level of biochemical markers and diagnostic calculation indices: Carbohydrate Antigen 125 (СА 125), Carbohydrate Antigen 19-9, Carcinoembryonic Antigen, Human Epididymis protein 4 (HE4), Risk of Ovarian Malignancy Algorithm (ROMA), Risk of Malignancy Index (RMI). All patients underwent determination of the level of cancer markers CA 125 and HE4, followed by calculation of the RMI and ROMA indices for premenopause, gray scale ultrasound examination with Doppler blood flow assessment was performed. Next, a contrast-enhanced ultrasound examination (CEUS) was performed.&#x0D; Results. Sensitivity (Se) of the Ovarian-Adnexal Imaging-Reporting-Data System (O-RADS) in predicting tumor malignancy was 84.8% (95% confidence interval 95% CI 8088), specificity (Sp) 88.1% (95% CI 8591), accuracy (Acc) 0.86 (95% CI 0.820.90), odds ratio (OR) 41.18 (95% CI 21.080.7), area under the curve (AUC) 0.744. Se of CEUS in predicting malignancy was 90.9% (95% CI 8595), Sp 92.5% (95% CI 8997), Acc 0.92 (95% CI 0.880.96), OR 150.0 (95% CI 76.5294.0), AUC 0.895.&#x0D; Conclusion. Patients with O-RADS 2 are shown to be monitored by a gynecologist for 6 months with a control ultrasound examination once every 3 months. When O-RADS 3 criteria are identified, it is recommended to include the determination of cancer markers and surgical treatment in a gynecological hospital with subsequent morphological examination of the obtained material as a preoperative diagnosis. The identification of O-RADS 4 and O-RADS 5 criteria requires additional examination methods, such as the study of cancer markers (CA 125, HE4, ROMA, RMI), contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging. CEUS showed high diagnostic efficiency in the presence of O-RADS 4 criteria, which made it possible to determine the necessary management tactics for patients with complex tumors. If the characteristics of the tumor are unclear, it is necessary to consider the possibility of surgical treatment in an oncological hospital.

Experience of using contrast-enhanced ultrasound examination in the most common malignant neoplasms of the liver

Aim. To study the features of contrast enhancement of malignant neoplasms of the liver in patients with and without cirrhosis (LC), to study the differences in the dynamics of contrast enhancement of liver are metastatic lesions (MTS) and hepatocellular carcinoma (HCC).Material and methods. A retrospective analysis results 58 patients with HCC (group 1) and 51 patients with liver metastases (group 2) was carried out based on morphological data. According to the criterion for the presence of LC, group 1 was divided into two subgroups. The main method of radiological diagnostics was contrast enhancement ultrasound (CEUS).Results. The indicators of the dynamics of the Wash-in of an ultrasound contrast agent into the HCC node and the dynamics of the drug WASH-OUT from the focus in patients with LC did not significantly differ from those in patients without cirrhosis. HCC is characterized by the onset of leaching of the ultrasound contrast agent after 62 seconds from the beginning of the study, which significantly differs from MTS (p &lt;0.05). The parameters in predicting the G3 stage of the tumor were as follows: the parameter “onset of WASH-OUT” of the from the focus &lt;79 sec, the parameter “time of maximum WASH-OUT” of the ultrasound contrast agent &lt;270 seconds. In our opinion, certain difficulties are presented by the diagnosis of highly differentiated carcinomas due to the absence of the WASH-OUT phenomenon in 50% of patients. Differential diagnosis of metastases should be based on a combination of a number of signs, the most important of which, in our opinion, are: early onset of elution of ultrasound contrast agent, “black hole” symptom, peripheral ring-shaped enhancement in arterial phase.Conclusion. The data obtained with the help of CEUS confirm the effect of “arterialization of hepatic blood flow” in patients with LC. Differences in the parameters of contrasting HCC nodes in subgroups of patients with and without LC are not statistically significant. The polymorphism of the signs detected in MTS in the liver is due to the morphology of the primary tumor and the size of the neoplasms. Differential diagnosis should be based on a combination of signs of the dynamics of ultrasound contrast agents.

A Method for Reducing Variability Across Dual-Energy CT Manufacturers in Quantification of Low Iodine Content Levels.

BACKGROUND. Clinical use of the dual-energy CT (DECT) iodine quantification technique is hindered by between-platform (i.e., across different manufacturers) variability in iodine concentration (IC) values, particularly at low iodine levels. OBJECTIVE. The purpose of this study was to develop in an anthropomorphic phantom a method for reducing between-platform variability in quantification of low iodine content levels using DECT and to evaluate the method's performance in patients undergoing serial clinical DECT examinations on different platforms. METHODS. An anthropomorphic phantom in three body sizes, incorporating varied lesion types and scanning conditions, was imaged with three distinct DECT implementations from different manufacturers at varying radiation exposures. A cross-platform iodine quantification model for correcting between-platform variability at low iodine content was developed using the phantom data. The model was tested in a retrospective series of 30 patients (20 men, 10 women; median age, 62 years) who each underwent three serial contrast-enhanced DECT examinations of the abdomen and pelvis (90 scans total) for routine oncology surveillance using the same three DECT platforms as in the phantom. Estimated accuracy of phantom IC values was summarized using root-mean-square error (RMSE) relative to known IC. Between-platform variability in patients was summarized using root-mean-square deviation (RMSD). RMSE and RMSD were compared between platform-based IC (ICPB) and cross-platform IC (ICCP). ICPB was normalized to aorta and portal vein. RESULTS. In the phantom study, mean RMSE of ICPB across platforms and other experimental conditions was 0.65 ± 0.18 mg I/mL compared with 0.40 ± 0.08 mg I/mL for ICCP (38% decrease in mean RMSE; p < .05). Intrapatient between-platform variability across serial DECT examinations was higher for ICPB than ICCP (RMSD, 97% vs 88%; p < .001). Between-platform variability was not reduced by normalization of ICPB to aorta (RMSD, 97% vs 101%; p = .12) or portal vein (RMSD, 97% vs 97%; p = .81). CONCLUSION. The developed cross-platform method significantly decreased between-platform variability occurring at low iodine content with platform-based DECT iodine quantification. CLINICAL IMPACT. With further validation, the cross-platform method, which has been implemented as a web-based app, may expand clinical use of DECT iodine quantification, yielding meaningful IC values that reflect tissue biologic viability or treatment response in patients who undergo serial examinations on different platforms.

Experience of using contrast-enhanced ultrasound examination in the most common malignant neoplasms of the liver

Aim. To study the features of contrast enhancement of malignant neoplasms of the liver in patients with and without cirrhosis (LC), to study the differences in the dynamics of contrast enhancement of liver are metastatic lesions (MTS) and hepatocellular carcinoma (HCC).Material and methods. A retrospective analysis results 58 patients with HCC (group 1) and 51 patients with liver metastases (group 2) was carried out based on morphological data. According to the criterion for the presence of LC, group 1 was divided into two subgroups. The main method of radiological diagnostics was contrast enhancement ultrasound (CEUS).Results. The indicators of the dynamics of the Wash-in of an ultrasound contrast agent into the HCC node and the dynamics of the drug WASH-OUT from the focus in patients with LC did not significantly differ from those in patients without cirrhosis. HCC is characterized by the onset of leaching of the ultrasound contrast agent after 62 seconds from the beginning of the study, which significantly differs from MTS (p &lt;0.05). The parameters in predicting the G3 stage of the tumor were as follows: the parameter “onset of WASH-OUT” of the from the focus &gt;&lt;79 sec, the parameter “time of maximum WASH-OUT” of the ultrasound contrast agent &gt;&lt;270 seconds. In our opinion, certain difficulties are presented by the diagnosis of highly differentiated carcinomas due to the absence of the WASH-OUT phenomenon in 50% of patients. Differential diagnosis of metastases should be based on a combination of a number of signs, the most important of which, in our opinion, are: early onset of elution of ultrasound contrast agent, “black hole” symptom, peripheral ring-shaped enhancement in arterial phase.&gt;Conclusion. The data obtained with the help of CEUS confirm the effect of “arterialization of hepatic blood flow” in patients with LC. Differences in the parameters of contrasting HCC nodes in subgroups of patients with and without LC are not statistically significant. The polymorphism of the signs detected in MTS in the liver is due to the morphology of the primary tumor and the size of the neoplasms. Differential diagnosis should be based on a combination of signs of the dynamics of ultrasound contrast agents.

Adrenal Mass Characterization in the Era of Quantitative Imaging: State of the Art.

Simple SummaryNon-invasive characterization of adrenal lesions requires a rigorous approach. Although CT is the cornerstone of adrenal lesion characterization, a multimodality multiparametric imaging approach helps improve confidence in adrenal lesion characterization. Detection and characterization of adrenal lesions have evolved during the past two decades. Although the role of imaging in adrenal lesions associated with hormonal secretion is usually straightforward, characterization of non-functioning adrenal lesions may be challenging to confidently identify those that need to be resected. Although many adrenal lesions can be readily diagnosed when they display typical imaging features, the diagnosis may be challenging for atypical lesions. Computed tomography (CT) remains the cornerstone of adrenal imaging, but other morphological or functional modalities can be used in combination to reach a diagnosis and avoid useless biopsy or surgery. Early- and delayed-phase contrast-enhanced CT images are essential for diagnosing lipid-poor adenoma. Ongoing studies are evaluating the capabilities of dual-energy CT to provide valid virtual non-contrast attenuation and iodine density measurements from contrast-enhanced examinations. Adrenal lesions with attenuation values between 10 and 30 Hounsfield units (HU) on unenhanced CT can be characterized by MRI when iodinated contrast material injection cannot be performed. 18F-FDG PET/CT helps differentiate between atypical benign and malignant adrenal lesions, with the adrenal-to-liver maximum standardized uptake value ratio being the most discriminative variable. Recent studies evaluating the capabilities of radiomics and artificial intelligence have shown encouraging results.