Nonionic Contrast Research Articles

Abstract 4119169: Navigating Complexity: The Carlino Technique in Multivessel Percutaneous Coronary Intervention for Chronic Total Occlusion

Introduction: Since the advent of percutaneous coronary intervention (PCI), the scope of this therapeutic intervention has broadened to include cases of life-threatening multivessel coronary artery disease that previously may have only been corrected surgically. PCI has become a common treatment of chronic total occlusion, and techniques continue to be developed to tackle more challenging cases. We present a complex case of NSTEMI with multi-vessel coronary artery disease treated with PCI via the Carlino technique. Case Description: A 60-year-old female with a history of hypertension, diabetes mellitus, and ischemic heart disease presented with severe chest pain that radiated to the neck and was associated with nausea and vomiting. Her EKG showed marked left-axis deviation, ST depressions in V2-V4, and RBBB. She was diagnosed with NSTEMI with a thrombolysis in myocardial infarction (TIMI) score of 5. She was loaded with aspirin and clopidogrel and was taken for left heart catheterization (LHC), which demonstrated three-vessel coronary artery disease with chronic 100% occlusion of the proximal left anterior descending artery, ostial 60-70% stenosis, and proximal 90-95% diseased left circumflex artery, while her right coronary artery had proximal 20-30% obstruction and mid 50-60% with right to left filling. The patient was advised CABG by the heart team, but the patient refused, and PCI was attempted on a shared decision basis. PCI was successful with the use of the Carlino technique: 0.5 ml of contrast dye was injected through a microcatheter to hydraulically recanalise the occlusion. The patient showed dramatic improvement and was discharged home on oral medications. Discussion: Treating multi-vessel coronary artery disease and CTO is challenging. PCI, particularly with the Carlino technique, offers a reliable approach. This technique, a modification of contrast-guided STAR, involves gentle contrast injection via microcatheter to modify plaque compliance and provide topographic information with regards to equipment location within vasculature, enhancing procedural success, especially in cases with impenetrable caps or calcified areas. Conclusion: This case is an example of how adaptive PCI techniques, such as the Carlino technique, can be employed to tackle complex instances of MvCAD that previously may have only been surgically corrected.

Quantifying Lower Extremity Blood Flow using Low-Dose CT Perfusion: Validation in a swine model

Abstract Background Quantitative assessment of blood flow in peripheral extremities in conjunction with simultaneous CT angiography measurements can improve risk assessment and provide a critical decision-making tool for patients across a wide spectrum of vascular disease severity. Purpose This study assessed the reproducibility and accuracy of lower extremity blood flow measurements with a low-dose first-pass analysis CT perfusion technique. Materials and Methods This prospective study utilized 16 Yorkshire Swine to obtain lower extremity blood flow CT measurements at baseline and under induced femoral stenosis using a vascular occluder. Thirty-three pairs of CT measurements evaluated reproducibility, and 43 CT measurements assessed accuracy against ultrasound flow probe references. Contrast agent and saline chaser were both injected peripherally at a rate of 5 mL/s. Bolus tracking was used, and a pre-contrast and post-contrast helical scan were acquired at the base and approximately the peak of the femoral enhancement (CT angiogram), respectively. The acquired data were then used as analytical inputs into a first-pass analysis model to derive perfusion in mL/min/g. The reproducibility and accuracy of lower extremity perfusion measurements were assessed via Mixed model regression and Bland-Altman analysis. Results Calculated CT perfusion measurements derived from first-pass analysis technique (PCT), and the reference standard ultrasound perfusion measurements (Pref) were related by PCT = 1.06 Pref + 0.00 (r2= 0.90, Root-Mean-Square Error = 0.01 mL/min/g). The first (P1) and second (P2) CT perfusion measurements were related by P2 = 0.98 P1 + 0.02 (r = 0.97, Root-Mean-Square Error = 0.11 mL/min/g). The average effective dose of perfusion measurement using first-pass analysis technique was calculated to be only 2.13 mSv. Conclusion : The low-dose quantitative CT perfusion technique can accurately measure lower extremity perfusion (mL/min/g) using only two helical scans. The CT angiogram and perfusion measurements can be used as a comprehensive technique for morphological and physiological assessment of limb ischemia.

Bladder Adenocarcinoma in a Constellation of Multiple Site Malignancies: An Unusual Case and Systematic Review

Background and Objectives: Multiple primary malignant tumors represent a small percentage of the total number of oncological cases and can involve either metachronous or synchronous development and represent challenges in diagnosis, staging, and treatment planning. Our purpose is to present a rare case of bladder adenocarcinoma in a female patient with multiple primary malignant tumors and to provide systematic review of the available literature. Materials and Methods: A 67-year-old female patient was admitted with altered general condition and anuria. The past medical history of the patient included malignant melanoma (2014), cervical cancer (2017), colon cancer (2021), obstructive anuria (2023), and liver metastasectomy (2023). Transurethral resection of bladder tumor was performed for bladder tumors. Results: Contrast CT highlighted multiple pulmonary metastases, a poly nodular liver conglomerate, retroperitoneal lymph node, II/III grade left ureterohydronephrosis, and no digestive tract tumor masses. The pathological result of the bladder resection showed an infiltrative adenocarcinoma. Conclusions: The difference between primary bladder adenocarcinoma tumor and metastatic colorectal adenocarcinoma is the key for the future therapeutic strategy. Identification and assessment of risk factors such as viral infection, radiotherapy, chemotherapy, smoking, and genetics are pivotal in understanding and managing multiple primary malignant tumors. Personalized prevention strategies and screening programs may facilitate the early detection of these tumors, whether synchronous or metachronous. The use of multicancer early detection (MCED) blood tests for early diagnosis appears promising. However, additional research is needed to standardize these techniques for cancer detection.

Detailed Images of Deep Brain Stimulation Leads Using Micro-CT

Introduction: One of the challenges in directional deep brain stimulation (DBS) is to determine the orientation of implanted electrodes relative to targeted regions. Post-operative images must be aligned with a model of the implanted lead, usually a computer-based model provided by the manufacturer. This paper shows that models can alternatively be obtained by capturing images of individual leads using micro-CT, a high-resolution CT technique. Contrary to computer-aided design models, lead models generated this way provide realistic X-ray contrast and finer details. Methods: We scanned DBS leads from various vendors using a Bruker SkyScan 1276 micro-CT system. To reduce beam-hardening artefacts, samples were scanned at maximum X-ray tube voltage (100 kV) and with copper filtering. Images were made publicly available for download and 3D visualisation. Conclusion: Detailed images of single DBS leads can be generated using standard micro-CT systems. Their use as reference models could improve lead orientation algorithms, in particular those dedicated to X-ray modalities. Furthermore, the possibility to share models online could broaden access for clinical research.

Supracostal ultrasound guided approach percutaneous nephrolithotomy (SUGA-PNL) versus retrograde intrarenal surgery for large volume isolated upper calyceal stones: a prospective randomized analysis

To assess outcomes of supracostal ultrasound guided approach percutaneous nephrolithotomy (SUGA-PNL) and retrograde intrarenal surgery (RIRS) in isolated large volume upper calyceal stones (UCS). This was a prospective randomized study including patients with isolated UCS > 20mm. The patients were randomized into two groups: group (P) (SUGA-PNL) and group (R) (RIRS). Patients’ demographics, stones characteristics, operative, and postoperative outcomes essentially the stone free rate (SFR) and complications rate were documented. The stone clearance was defined as no fragments or residual fragments less than 2mm in the one month non contrast CT scan follow up. Eighty-nine patients opted to undergo the procedure according to the preoperative randomization. Four patients, 2 patients from each group, lost to follow up and other 2 patients were excluded from group (R) due to a tight ureter. Both groups were comparable as regards the preoperative demographics and stone characteristics. There were statistically significant differences regarding total operative time, the change in hemoglobin level, and postoperative pain score (P: 0.024, 0.010 and 0.032 respectively). The SFR was 88.1% in group (P) compared to 73.2% in group (R) (P: 0.019). Moreover, it did not differ significantly between both groups regarding the intraoperative and postoperative complications. No visceral and thoracic injuries were documented in group (P). On other side, 6 patients (14.6%) from group (R) had different grades of ureteral injury during access sheath placement. SUGA-PNL is a safe and effective treatment modality for UCS > 20mm with a higher SFR than RIRS.

Role of liver enzymes in patients with blunt trauma to liver on conservative management

Background: When blunt abdominal trauma occurs, the liver is the organ most often affected. The liver enzymes are often elevated in blunt trauma to the liver. However, the variation of liver enzymes among various grades of liver injury is not clear. The aim of our investigation is to determine the variation of liver enzymes across various grades of liver injury as well as whether it affects any change in management including surgical intervention. Methods: Our research was a prospective observational study. Patients of blunt abdominal trauma having a liver damage which was detected on a contrast CT scan and managed conservatively were included. They were categorized as per the AAST (American Association for the Surgery of Trauma) system. Various biochemical markers including liver enzymes were compared between the groups. Any change in management or need for intervention was found out. Results: A total of 35 patients has been included. Ages between 31 and 40 accounted for the majority of cases (34.3%). Our study showed male preponderance (85.7%). Most patients presented to the hospital within 24 hours of trauma (82.9%). Most of our patients had blood transfusions during their hospital stay (71.4%). AAST grade III injury was predominant (48.6%). Subgroup analysis between minor and major liver injury patients was done. No significant distinction was seen among the two groups concerning the assessed biochemical parameters. No significant variation was observed regarding the necessity for intervention. Conclusions: Liver enzymes can not be used to differentiate among various grades of liver injury. Patients who are managed conservatively can be managed so with close monitoring and supportive treatment without the need for any intervention. However, larger and randomized studies are needed to validate the results.

Non-contrast-enhanced MR-angiography of the abdominal arteries: intraindividual comparison between relaxation-enhanced angiography without contrast and triggering (REACT) and 4D contrast-enhanced MR-angiography.

To evaluate Relaxation-Enhanced Angiography without Contrast and Triggering (REACT), a novel 3D isotropic flow-independent non-contrast-enhanced magnetic resonance angiography (non-CE-MRA) for imaging of the abdominal arteries, by comparing image quality and assessment of vessel stenosis intraindidually with 4D CE-MRA. Thirty patients (mean age 35.7 ± 16.8years; 20 females) referred for the assessment of the arterial abdominal vasculature at 3T were included in this retrospective, single-centre study. The protocol comprised both 4D CE-MRA and REACT (navigator-triggering, Compressed SENSE factor 10, nominal scan time 02:54min, and reconstructed voxel size 0.78 × 0.78 × 0.85 mm3). Two radiologists independently evaluated 14 abdominal artery segments for stenoses, anatomical variants, and vascular findings (aortic dissection, abdominal aorta aneurysms and its branches). Subjective image quality was assessed using a 4-point Likert scale (1 = non-diagnostic, 4 = excellent). REACT had a total acquisition time of 5:36 ± 00:40min, while 4D CE-MRA showed a total acquisition time (including the native scan and bolus tracking sequence) of 3:45 ± 00:59min (p = 0.001). Considering 4D CE-MRA as the reference standard, REACT achieved a sensitivity of 87.5% and specificity of 100.0% for relevant (≥ 50%) stenosis while detecting 89.5% of all vascular findings other than stenosis. For all vessels combined, subjective vessel quality was slightly higher in 4D CE-MRA (3.0 [IQR: 2.0; 4.0.]; P = 0.040), although comparable to REACT (3.0 [IQR: 2.0; 3.5]). In a short scan time of about 5min, REACT provides good diagnostic performance for detection of relevant stenoses, variants, and vascular findings of the abdominal arteries, while yielding to 4D CE-MRA comparable image quality.

Peroral endoscopic myotomy as a new approach in the treatment of patients with achalasia cardia

Background. Achalasia cardia is a disease characterized by an esophageal motility disorder in which the lower esophageal sphincter fails to fully relax in response to swallo-wing and esophageal motility progressively decreases. The aim of the work is to improve the outcomes of endoscopic treatment for esophageal achalasia by modifying peroral endoscopic myotomy (POEM) in stage II–III achalasia cardia. Materials and methods. In 2019–2023, 35 (100.0 %) patients with stage II–III achalasia cardia were examined and underwent POEM at the multidisciplinary surgical department in the Educational and Scientific Medical Center “University Clinic” of the Zaporizhzhia State Medical and Pharmaceutical University. The diagnosis was made based on the following data: complaints, clinical course, esophagram, endoscopic diagnosis, and computed tomography. The average age of the patients was 50.0 ± 15.7 years. Analyzing the frequency of this disease according to the WHO age classification, there were 16 (45.7 %) young, 8 (22.9 %) middle-aged, 10 (28.6 %) elderly, and 1 (2.8 %) senile patient. The group was equal in terms of gender: 16 men (45.7 %) and 19 women (54.3 %), p = 0.9654. Inclusion criteria: age over 18 years, stage II–III achalasia cardia, informed consent of a patient. Exclusion criteria: achalasia cardia stage I, as we believe that at this stage only conservative treatment and balloon dilatation are indicated; achalasia cardia stage IV for which only Heller myotomy with Dor fundoplication are indicated. Results. All patients of the study group were operated by the method of POEM under total intravenous ane-sthesia with artificial lung ventilation. Esophageal myotomy was performed along the posterior wall, considering the risk of recurrence and preservation of the anterior wall for repeated peroral myotomy or laparoscopic Heller myotomy. The length of the myotomy was determined depending on the stage of achalasia. So, for stage II, the beginning of the endoscopic tunnel formation and myotomy was determined from the first persistent esophageal spasm, which most often corresponded to a distance of 25.0 ± 2.0 cm from the incisors and, accordingly, myotomy of the esophagus, lower esophageal sphincter, and gastric myotomy averaged 15.0 ± 3.0 cm. We noted that in all operated patients six months after the operation, a propulsive activity appeared during contrast X-ray of the esophagus, and its volume decreased from 5.6 ± 0.4 cm at stage II to 2.3–4.1 cm (p = 0.0324) and from 7.4 ± 0.2 cm at stage III to 3.6 ± 0.8 cm (p = 0.0267), which indicates a decreased pressure in the lower esophageal sphincter after surgery. Based on the evaluation of the results of multichannel esophageal gastric pH monitoring, reflux was confirmed in 1 (6.7 %) patient with achalasia stage II and in 1 (5.0 %) case with achalasia stage III. Conclusions. Peroral endoscopic myotomy is an effective minimally invasive method of treating patients with achalasia cardia stage II–III. According to the Eckardt symptom score, reliable results were achieved already one month after surgery: 7.6 ± 1.1 points before surgery and 2.1 ± 0.4 points when evaluated one month after surgical treatment (p < 0.0001, U = 475.0). Given the effectiveness and minimal trauma, the low risk of postoperative complications, a significant reduction in hospital stay and rapid postoperative rehabilitation, POEM can be an alternative to laparoscopic Heller myotomy.

The osteohistology of Orthosuchus stormbergi using synchrotron radiation microcomputed tomography.

Orthosuchus stormbergi was a small-bodied crocodyliform, representative of a diverse assemblage of Early Jurassic, early branching crocodylomorph taxa from the upper Elliot Formation of South Africa. The life history of these early branching taxa remains poorly understood, with only sparse investigations into their osteohistology, yet species like Orthosuchus have potential to inform about the macroevolution of growth strategies on the stem leading to crown crocodilians. In order to elucidate the growth patterns of Orthosuchus, we used propagation phase contrast X-ray synchrotron micro-computed tomography to virtually image the osteohistology of the postcrania of two specimens, including multiple elements from the type (SAM-PK-K409), and the femur of a referred specimen (BP/1/4242). In total, we scanned nine mid-diaphyseal sections of the humerus, radius, ulna, radiale, femur, tibia, fibula, and a rib. We then compared our results to osteohistological sections of crocodylomorph taxa from the published literature. Our results show that the most predominant bone tissue type in Orthosuchus is lamellar, with a few patches of woven and parallel-fibred bone. The type specimen contains four to five lines of arrested growth and the hindlimb elements present outer circumferential lamellae, whereas the referred specimen contains six to seven. Both specimens grew at similar rates, reaching adult skeletal body size at year four or five. The sectioned bones, most notably the radius and ulna, are comparatively thick walled and compact. Our virtual osteohistological sections are one of the first for an early branching crocodyliform, and the broad sample of skeletal elements makes Orthosuchus a key anchor point for understanding the plesiomorphic life history traits of the clade.

Advanced three-dimensional X-ray imaging unravels structural development of the human thymus compartments

BackgroundThe thymus, responsible for T cell-mediated adaptive immune system, has a structural and functional complexity that is not yet fully understood. Until now, thymic anatomy has been studied using histological thin sections or confocal microscopy 3D reconstruction, necessarily for limited volumes.MethodsWe used Phase Contrast X-Ray Computed Tomography to address the lack of whole-organ volumetric information on the microarchitecture of its structural components. We scanned 15 human thymi (9 foetal and 6 postnatal) with synchrotron radiation, and repeated scans using a conventional laboratory x-ray system. We used histology, immunofluorescence and flow cytometry to validate the x-ray findings.ResultsApplication to human thymi at pre- and post-natal stages allowed reliable tracking and quantification of the evolution of parameters such as size and distribution of Hassall’s Bodies and medulla-to-cortex ratio, whose changes reflect adaptation of thymic activity. We show that Hassall’s bodies can occupy 25% of the medulla volume, indicating they should be considered a third thymic compartment with possible implications on their role. Moreover, we demonstrate compatible results can be obtained with standard laboratory-based x-ray equipment, making this research tool accessible to a wider community.ConclusionsOur study allows overcoming the resolution and/or volumetric limitations of existing approaches for the study of thymic disfunction in congenital and acquired disorders affecting the adaptive immune system.

The polar vessel sign: insights from CT imaging analysis in Asian Indian primary hyperparathyroidism.

Data on the polar vessel sign (enlarged feeding vessel terminating in parathyroid lesions) on four-dimensional computed tomography (4D-CT) is limited. We performed a retrospective analysis to determine the prevalence, predictors, and adjunctive utility of polar vessel sign in pre-operative 4D-CT of patients with primary hyperparathyroidism (PHPT). One radiologist blinded to the patients' details reported the 4D-CT of eighty-four operated patients with histopathology-proven single-gland PHPT. Two protocols were used to obtain arterial-phase images: timed via bolus tracking (n = 41) or fixed at 20 s after contrast injection (n = 43). Seventy-one patients were symptomatic for PHPT, with median serum calcium 12.1 mg/dL. On the arterial phase of 4D-CT, 88.1% of lesions had the polar vessel sign, including 7/9 asymptomatic patients, 6/6 parathyroid carcinomas, and 3/4 ectopic(1:mediastinum, 2:thyro-thymic ligament). Predictors of polar vessel sign were maximum lesion dimension (2.2 vs. 1.4 cm; P = 0.03), solid-cystic CT morphology (47.3% vs. none; P = 0.004), and bolus tracking-timed arterial phase (55.4% vs. none; P = 0.001). Of these, bolus tracking improved the polar vessel's visualization (100% vs. 76.7%; P = 0.001) independent of lesion dimension and solid-cystic morphology. The latter two predicted polar vessel sign in images obtained at a fixed interval (20 s). A significantly lower proportion of bolus tracking-timed scans had lesion percentage arterial enhancement (PAE) < 128.9% (2/41 vs. 9/43; P = 0.04). Even with suboptimal PAE, the polar vessel helped identify 9/11 lesions. The polar vessel sign demonstrated an additive role to PAE during CT reporting. Bolus tracking is valuable in optimizing vessel and tumor arterial enhancement and is easily incorporated into parathyroid 4D-CT protocol.

Image Quality and Lesion Detectability of Low-Concentration Iodine Contrast and Low Radiation Hepatic Multiphase CT Using a Deep-Learning-Based Contrast-Boosting Model in Chronic Liver Disease Patients.

This study investigated the image quality and detectability of double low-dose hepatic multiphase CT (DLDCT, which targeted about 30% reductions of both the radiation and iodine concentration) using a vendor-agnostic deep-learning-based contrast-boosting model (DL-CB) compared to those of standard-dose CT (SDCT) using hybrid iterative reconstruction. The CT images of 73 patients with chronic liver disease who underwent DLDCT between June 2023 and October 2023 and had SDCT were analyzed. Qualitative analysis of the overall image quality, artificial sensation, and liver contour sharpness on the arterial and portal phase, along with the hepatic artery clarity was conducted by two radiologists using a 5-point scale. For quantitative analysis, the image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured. The lesion conspicuity was analyzed using generalized estimating equation analysis. Lesion detection was evaluated using the jackknife free-response receiver operating characteristic figures-of-merit. Compared with SDCT, a significantly lower effective dose (16.4 ± 7.2 mSv vs. 10.4 ± 6.0 mSv, 36.6% reduction) and iodine amount (350 mg iodine/mL vs. 270 mg iodine/mL, 22.9% reduction) were utilized in DLDCT. The mean overall arterial and portal phase image quality scores of DLDCT were significantly higher than SDCT (arterial phase, 4.77 ± 0.45 vs. 4.93 ± 0.24, AUCVGA 0.572 [95% CI, 0.507-0.638]; portal phase, 4.83 ± 0.38 vs. 4.92 ± 0.26, AUCVGA 0.535 [95% CI, 0.469-0.601]). Furthermore, DLDCT showed significantly superior quantitative results for the lesion contrast-to-noise ratio (7.55 ± 4.55 vs. 3.70 ± 2.64, p < 0.001) and lesion detectability (0.97 vs. 0.86, p = 0.003). In patients with chronic liver disease, DLDCT using DL-CB can provide acceptable image quality without impairing the detection and evaluation of hepatic focal lesions compared to SDCT.

Bolus tracking from pulsed x-ray projections: A feasibility study using a five-dimensional cardiac CT contrast dynamics model.

Cardiac computed tomography (CT) exams are some of the most complex CT exams due to the need to carefully time the scan when the heart chambers are near the peak contrast concentration. With current "bolus tracking" and "timing bolus" techniques, after contrast medium is injected, a target vessel or chamber is scanned periodically, and images are reconstructed to monitor the opacification. Both techniques have opportunities for improvement, such as reducing the contrast medium volume, the exam time, the number of manual steps, and improving the robustness of correctly timing the peak opacification. The objective of our study is to (1) develop a novel autonomous cardiac CT clinical workflow to track contrast bolus dynamics directly from pulsed x-ray projections, (2) develop a new five-dimensional virtual cardiac CT data generation tool with programmable cardiac profiles and bolus dynamics, and (3) demonstrate the feasibility of projection-domain prospective bolus tracking using a neural network trained and tested with the virtual data to find the contrast peak. In our proposed workflow, pulsed mode projections (PMPs) are acquired with a wide-open collimator under sparse view conditions (monitoring phase). Each time a new PMP is acquired, the neural network is used to estimate the contrast enhancement inside the target chambers. To train such a network, we introduce a new approach to generate clinically realistic virtual scan data based on a five-dimensional cardiac model, by synthesizing user-defined contrast bolus dynamics and patient electrocardiogram profiles. In this study, we investigated a scenario with one single PMP per rotation. To find the optimal PMP view angle, 20 angles were explored. For each angle, 300 virtual exams were generated from 115 human subject datasets and divided into training, validation, and testing groups. Twenty neural networks were trained and evaluated in total to find the optimal network. Finally, a simple bolus peak time estimation algorithm was developed and evaluated by comparing to the ground truth bolus peak time. To evaluate the accuracy of a bolus time-intensity curve estimated by the network, the cosine similarity between the estimation and the ground truth was computed. The cosine similarity was larger than 0.97 for all projection angles. A view angle corresponding to the x-ray tube at 30 degrees from vertical (left-anterior of subject) showed the lowest errors. The amplitude of the estimated bolus curves (in Hounsfield Units) was not always correctly predicted, but the shape was accurately predicted. This resulted in an RMSE of 1.23s for the left chambers and 0.78s for the right chambers in the contrast peak time estimation. In this study, we proposed an innovative real-time way to predict the contrast bolus peak in cardiac CT as well as an innovative approach to train a neural network using virtual but clinically realistic data. Our trained network successfully estimated the shape of the time-intensity curve for the target chambers, which led to accurate bolus peak time estimation. This technique could be used for autonomous diagnostic cardiac CT to trigger a diagnostic scan for optimal contrast enhancement.

Successful management of megaoesophagus associated with hypothyroidism in a dog: A case report

A seven-year-old male Dachshund was presented with a history of chronic regurgitation and weight loss for two months. On clinical examination, dry and rough hair coat with alopecia on nose bridge and rat tail appearance were observed. Elevated rectal temperature and increased respiratory rate were noticed. Auscultation of lung field revealed mild crackles. Leucocytosis and mild anaemia were evident on complete blood count. Hypercholesterolaemia, hypertriglyceridaemia and elevation of Lactate dehydrogenase (LDH) and Alkaline phosphatase (ALP) were observed in serum biochemistry. The total T4 (TT4) value was low and canine-specific thyroid stimulating hormone (cTSH) was elevated. Megaoesophagus was confirmed by plain radiography. Barium contrast radiograph revealed generalised dilatation with pooling of barium in the oesophagus. The animal was treated with levothyroxine sodium at 0.02 mg/kg BW PO BID and bethanechol at 10 mg PO TID. Supportive therapy included antibiotics, antacids and antiemetics. Elevated feeding was advised. The animal had no episodes of regurgitation even after one month Keywords: Megaoesophagus, hypothyroidism, bethanechol, elevated feeding

X-ray Endovascular Embolization for Splenic Artery Aneurysm Complicated by Intestinal Bleeding

Introduction. Splenic artery aneurysms refer to the most common visceral artery aneurysms. However, they are diagnosed quite rarely, since about 80% of them appear asymptomatic. Clinically, splenic artery aneurysms manifest themselves through their complications, including hemorrhage into pancreatic cysts or intra­abdominal bleeding due to their rupture, leading to lethality up to 8.5%. Other complications of splenic artery aneurysms appear extremely rare. The gold standard for the diagnosis of splenic artery aneurysms refers to digital subtraction angiography that enables their exact localization to be determined and aneurysm embolization to be performed. Materials and methods. In the period from 2015 to 2023, we observed 51 patients who underwent endovascular interventions on the splenic artery for hypersplenism (n = 32) and aneurysms (n = 19). In most cases, the aneurysms were asymptomatic. The paper presents a rare clinical case of splenic artery aneurysm complicated by recurrent intestinal bleeding. Results and discussion. Examination (EGD, CS) did not detect the source of recurrent intestinal bleeding. Contrast CT revealed a splenic artery aneurysm. Celiac angiography detected a large aneurysm (52×41 mm) of the splenic artery, closely adjacent to the lower horizontal branch of the duodenum. Endovascular embolization of the splenic artery was performed proximal to the aneurysm, resulting in complete occlusion of blood flow through the splenic artery and aneurysm. No repeated episodes of intestinal bleeding were observed after the intervention, thereby indicating the effectiveness of hemostasis. No signs of splenic ischemization were detected by clinical and examination data due to the preservation of blood flow through short splenic vessels. Conclusion. Endovascular embolization of the splenic artery is found to be an effective treatment for its complicated aneurysms.

Oral CT Contrast Agents: What's New and Why, From the AJR Special Series on Contrast Media.

Current CT oral contrast agents improve the conspicuity of and confidence in bowel and peritoneal findings in many clinical scenarios, particularly for outpatient and oncologic abdominopelvic imaging. Yet, existing positive and neutral oral contrast agents may diminish the detectability of certain radiologic findings, frequently in the same scans in which the oral contrast agent improves the detectability of other findings. With ongoing improvements in CT technology, particularly multienergy CT, opportunities are opening for new types of oral contrast agents to further improve anatomic delineation and disease detection using CT. The CT signal of new dark oral contrast agents and of new high-Z oral contrast agents promises to combine the strengths of both positive and neutral oral CT contrast agents by providing distinct CT appearances in comparison with bodily tissues, iodinated IV contrast agents, and other classes of new CT contrast agents. High-Z oral contrast agents will unlock previously inaccessible capabilities of multienergy CT, particularly photon-counting detector CT, for differentiating simultaneously administered IV and oral contrast agents; this technique will allow generation of rich 3D, intuitive, perfectly coregistered, high-resolution image sets with individual contrast agent "colors" that provide compelling clarity for intertwined intraabdominal anatomy and disease processes.

Solid-pseudopapillary neoplasm of the pancreas in a 12-year-old female; case report

Introduction and Importance: A solid pseudopapillary tumor of the pancreas is a rare solid neoplasm. It is an uncommon exocrine tumor that accounts for 1–3% of exocrine pancreatic tumors. Case Presentation: We have reported 2 cases of solid pseudopapillary neoplasm of the pancreas with a median age of 12 years, both in females with abdominal pain. Clinical Discussion: Both cases are in females with different treatment modalities. The patient underwent distal pancreatectomy in the first case and enucleation of mass from the distal pancreas in the second case because the size of the tumor is 5 cm and does not involve the bile duct and major pancreatic duct. Conclusion: We discussed 2 cases of solid pseudopapillary neoplasm of the pancreas both in a 12-year-old female—both the Patients presented with abdominal pain. The patient underwent a different treatment. The diagnosis was confirmed by radiological investigation through Non-contrast and Contrast CT and supported by histopathology findings.

Successful Neoadjuvant Chemotherapy and Surgical Removal of a Nonmetastatic Testicular Round Cell Tumor in a Solomon Island Eclectus Parrot (Eclectus roratus solomonensis).

An intracoelomic mass was palpated on an annual exam of a 24-year-old male Solomon Island eclectus parrot (Eclectus roratus solomonensis). The initial diagnostic workup included a complete blood count, plasma biochemistry panel, and coelomic ultrasound. Computed tomography was highly suggestive of a testicular mass. Tamoxifen and the gonadotropin-releasing hormone agonists leuprolide and deslorelin were administered as neoadjunctive endocrine therapies. Biopsy and histologic examination confirmed a testicular mass consistent with a round cell tumor. Four doses of carboplatin 15 mg/kg IV were administered as neoadjunctive chemotherapy, and testicular size decreased by approximately 95%. The remaining gross tumor was removed via orchidectomy with clean but narrow margins. Seven months following surgery, a contrast CT scan did not show any evidence of recurrence of or metastasis from the original mass. This is the first report of successful treatment of a testicular tumor in a psittacine with neoadjuvant chemotherapy and orchidectomy.

8774 An Uncommon Presentation Of A Large Silent Pheochromocytoma

Abstract Disclosure: M. Lozano: None. A. Pinero-Pilona: None. Background: The reported estimated incidence of pheochromocytoma is approximately 2-8 cases per 1 million people per year. Of those, silent pheochromocytomas will make up about 8%. Thus, biochemically silent and non-secreting pheochromocytomas are a very rare phenomenon. Clinical Case: A 74-year-old Caucasian female with significant past medical history of primary hypothyroidism, hypercholesterolemia, and nasal sinus carcinoma s/p surgery (in remission) presented to the clinic for endocrine evaluation of a right adrenal mass. The patient was asymptomatic and denied headaches, tachycardia, sweating, severe hypertension, diabetes, muscle weakness, easy bruising, or striae. The mass was initially diagnosed as an incidental finding after a contrast CT scan of the abdomen was performed for diverticulitis. The right adrenal enhancing mass was 2.3 x 3.9 x 4.1 cm in diameter. Subsequent MRI abdomen with and without contrast ordered by the referring physician showed that the adrenal mass had grown to 4.9 x 3.8 x 5.4 cm and was hyperenhancing in nature with central T2 hyperintense signal. Notably, multiple “parasitized and arborealized” vessels were detected within the mass. Such findings led us to suspect metastatic versus primary adrenal neoplasm such as cortical carcinoma as a working diagnosis. Other laboratory studies including plasma free metanephrines (&amp;lt;10 pg/mL, normal 0-88 pg/mL), plasma normetanephrines (29.2 pg/mL, normal 0-285.2 pg/mL) and 24-hour urine collections (24 hr urine epinephrine - 3 ug/24 hr [normal 0-20 ug/24 hr]; 24 hr urine norepinephrine - 75 ug/24 hr [normal 0-135 ug/24 hr]; 24 hr urine VMA - 3 mg/24 hr [normal 0-7.5 mg/24 hr]) were negative for pheochromocytoma. As her mass was greater than 4 cm in diameter, surgical referral was then recommended to the patient. Right adrenalectomy was performed. Pathology report was consistent with pheochromocytoma as supported by immunohistochemistry. Ki-67 proliferation index was 0-10% (average 3-4%, rare hotspots 10%). Atrophy and vascular ectasia were present in residual non-neoplastic adrenal cortex and medulla. Histology showed a nested growth pattern, absence of composite tumor elements, absence of necrosis, and no atypical mitoses. The incidence of non-secreting pheochromocytomas has been quoted to be 0.000064% (1). Conclusion: The case illustrates an uncommon presentation of a large, silent pheochromocytoma with negative plasma metanephrines accompanied by negative urine studies, which have a negative predictive value close to 100% in ruling out a pheochromocytoma. Our case emphasizes the importance of considering pheochromocytoma on the differential of adrenal masses with high attenuation or high enhancement even when biochemical studies suggest otherwise. Reference: (1) Radojkovic, D., et al. "CLINICALLY" SILENT GIANT PHEOCHROMOCYTOMA. CASE REPORT." Acta Endocrinologica (1841-0987) 9.1 (2013). Presentation: 6/1/2024

7029 Changes In Adrenal Gland Size Seen By Linear Assessment On Routine Abdominal CT During Critical Illness

Abstract Disclosure: D.R. Vangipuram: None. N. Bhagat: None. R. Borkar: None. N.T. Mazengia: None. S. Williams, MD: None. S.K. Majumdar: None. Introduction: During acute stress, the hypothalamus-pituitary-adrenal (HPA) axis is activated, ultimately releasing adrenocorticotropic hormone (ACTH) from the pituitary gland, which stimulates cortisol synthesis and release from the adrenal gland. During this process, ACTH also increases adrenal blood flow which may result in noticeable changes in adrenal gland size on imaging. A previous study compared adrenal gland volume in patients with and without sepsis and concluded that adrenal gland volume was found to be nearly double in sepsis compared with patients without sepsis(1). Another study that evaluated adrenal gland size on MDCT, to provide normal values for volumetry and linear dimensions, found a concordance between volumetric and linear assessment (by cumulative width), though volumetry was more reproducible(2). Method: This is a retrospective study that included 50 adult patients (age 18 and over) who underwent a non-contrast or contrast CT scan of the abdomen within 5 years prior to admission to the Intensive Care Unit (ICU) with any critical illness, and then had another CT of the abdomen during the admission to the ICU. We measured the maximum width of the body (corpus) and that of the medial and lateral limbs of both the adrenal glands, perpendicular to the long axis, as seen on CT. The total (cumulative) width was calculated by adding the width of the corpus and both the limbs of each adrenal gland. The measurements were made by two different radiologists, who were blinded both to the before/after ICU admission CTs, and to each other’s measurements. Results: There was concordance in the measurements made by both the radiologists. We used the averages of both their measurements for analysis. The mean cumulative width of each adrenal gland, i.e., corpus+medial limb+lateral limb (in mm), was: Right adrenal before ICU admission 13.52 (± 3.20); during ICU admission 13.24 (± 3.13); p 0.444. Left adrenal before ICU admission 16.03 (± 3.18); during ICU admission 15.12 (± 3.47); p 0.021. Conclusion: There was a statistically significant decrease in the size of the left adrenal gland during critical illness, but no significant change in the right. Our findings do not suggest an increase in adrenal gland size during ICU admission.