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Purpose: To investigate the effects of deep learning reconstruction on depicting arteries and providing suitable images for the evaluation of hemorrhages with abdominopelvic contrast-enhanced computed tomography (CT) compared with hybrid iterative reconstruction., Methods: This retrospective study included 16 patients (mean age: 54.2 ± 22.1 years; 8 men and 8 women) with acute hemorrhage who underwent contrast-enhanced CT. Unenhanced axial, arterial phase axial, arterial phase coronal, and delayed phase axial images were reconstructed with deep learning reconstruction, hybrid iterative reconstruction, and filtered back projection, which was used as a control in qualitative analyses. Circular and line regions of interest were placed on the aorta and superior mesenteric artery (SMA), respectively, in quantitative analyses. Using a blind process, 2 radiologists independently evaluated image noise, depiction of arteries, and suitability for the evaluation of hemorrhage in qualitative image analyses., Results: Image noise in deep learning reconstruction was significantly reduced compared with hybrid iterative reconstruction in the quantitative ( P < .001) and qualitative analyses (Reader 1, P ≤ .001 for all series; Reader 2, P = .002, .001, and < .001). The slope at the half maximum in deep learning reconstruction (123.8 ± 63.2 HU/mm) significantly improved compared with hybrid iterative reconstruction (105.3 ± 51.0 HU/mm) in the CT attenuation profile of the SMA ( P < .001). Qualitative analyses revealed a significantly improved depiction of arteries (Reader 1, P < .001 for all series; Reader 2, P = .037, .008, and < .001) and suitability for evaluating acute hemorrhage in the arterial phase image (Reader 1, P < .001 for both series; Reader 2, P = .041 and .004) with deep learning reconstruction compared with hybrid iterative reconstruction., Discussion: Deep learning reconstruction provided images with a significantly better depiction of arteries and more suitable quality arterial phase images for the evaluation of abdominopelvic hemorrhage compared with hybrid iterative reconstruction., Conclusion: Deep learning reconstruction is better for reconstructing abdominopelvic contrast-enhanced CT images when evaluating hemorrhages; however, a prospective study including a large number of patients is needed to strengthen the findings of this study., (© 2024 American Society of Radiologic Technologists.)

Background: Focused Assessment with Sonography in Trauma (FAST) examination is a point-of-care ultrasound study used to evaluate for abdominal hemorrhage, pneumothorax, or pericardial blood in trauma patients as an adjunct to their initial assessment. The quality of the image can be limited, and its diagnostic value is heavily dependent on operator skill. Our objective was to determine whether a standardized review process improved image quality and reduced incidence of nondiagnostic or insufficient imaging by 10% over a 6-month period. Study Design: Between July 1, 2021, and March 31, 2022, we evaluated 1106 trauma activations at our level II trauma center. Two exams per practitioner per month were reviewed by an emergency medicine trained traumatologist with specialized training in point-of-care ultrasound and board certification in echocardiography. Priority was given to exams on patients with known injuries identified on other studies. If there were no exams that matched these criteria, random exams were selected. Images were reviewed for image quality, diagnostic accuracy, and labeling with counseling given to the provider if indicated. Categorical variables were compared using chi squared analysis, while continuous non-normally distributed variables were compared using the Mann-Whitney U test. Results: A total of 305 FAST exams were reviewed (186 pre-intervention and 119 during intervention). Image quality improved from 46.3% (n = 31/65) to 79.0% (n = 94/119) ( P < .01) with need for counseling falling from 63.1% (n = 41/65) pre-QI to 42.0% (n = 50/119) post-QI ( P < .01). Incidence of detectable injury, BMI, ISS, and AIS body regions were consistent across the study period. This was seen in both the geriatric and non-geriatric cohorts despite a significant increase in ISS in the post-intervention geriatric patients. Discussion: A FAST review program is associated with improvement in image quality and decreased need for counseling of trauma providers., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction: Patients who present with hemorrhage from pelvic fractures have an increased risk of mortality with prolonged time to intervention. Identifying risk factors associated with hemorrhage can expedite treatment. In this study we explore clinical and radiographic predictors for angiography in trauma patients with pelvic fractures., Method: Retrospective, single-center review between 2009 and 2019 at a level 1 trauma center of all trauma patients with pelvic fractures. We excluded patients who died prior to arrival or in the trauma bay who did not undergo computed tomography ("CT"). Finalized attending descriptions of CT findings were reviewed, including size of hematomas, and presence of extravasation. Chi-square, Mann-Whitney U and multi-variate regressions were performed., Results: We analyzed 1,703 trauma patients with pelvic fractures. Most common mechanisms of injury included MVC (45 %), fall (27 %) and motorcycle accident (12 %). 48 % (819/1703) of patients had pelvic hematomas on CT scan. 17 %(138/819) of patients with a hematoma also had evidence of extravasation. Significant predictors for extravasation on CT included large hematoma on CT, AIS extremity ≥2, binder placement, increased ISS, HR, and decreased GCS and SBP (p < 0.005). Significant predictors for angiography were similar, including AIS extremity ≥2, binder placement, presence of moderate and large hematoma and active extravasation on CT (p < 0.01). Stepwise logistic regression model incorporated ISS, HR, AIS extremity score, binder placement, and contrast extravasation with an AUC = 0.9345., Conclusion: In this large retrospective review of traumatic pelvic fractures, specific clinical and radiographic factors were significantly associated with pelvic hematomas, extravasation and/or need for angiography. Future collaborative work with orthopedics and interventional radiology is planned to better triage pelvic fracture patients and identify those at risk for bleeding that require earlier intervention., Competing Interests: Declaration of competing interest All authors declare no relevant conflicts of interest pertinent to this work. Caroline Park and Adam Starr are advisors to TraumaCare.AI., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: Hemorrhage in osteoporotic pelvic ring fractures is a rare, but serious complication. Most bleeding comes from the bone or venous plexuses, but arterial injury does occur. The purpose of this study was to characterize a large geriatric pelvic fracture cohort and determine the prevalence of pelvic CT angiography (CTA) and subsequent need for arterial embolization., Methods: A cohort of geriatric pelvic fracture patients at two level 1 trauma centers was reviewed. Many epidemiologic and patient factors were collected for cohort characterization. The primary outcome was if patients underwent a CTA of the pelvis and subsequently underwent arterial embolization., Results: There were 457 patients included and mean age was 83.1 years (range 65-100). Most patients had a low energy mechanism (91.4 %). In-hospital mortality was recorded for 30 cases (6.6 %). Of these deaths, two received a pelvic CTA and two had an embolization procedure. Pelvic CTA was performed on 33 patients (7.2 %). Fourteen patients (3.0 %) had an arterial embolization procedure. A high energy mechanism of injury was associated with receiving a pelvic CTA (p = 0.0067). Mechanism of injury was not associated with undergoing an embolization procedure (p = 0.685)., Discussion: In the geriatric population, even patients with stable pelvic fractures can present with life-threatening arterial bleeding. A non-insignificant percentage of patients will require CTA for suspected bleeding (7.2 %) and embolization to treat confirmed arterial bleeding (3.0 %)., Conclusions: Bleeding events in geriatric pelvic ring injuries is a previously under researched area of orthopedic trauma. Further research is needed to elucidate the exact pathomechanisms of arterial injury and what patients or injury patterns are most significantly associated. Specifically, larger cohort sizes and evaluating our existing cohort with different injury classification systems may yield useful results., Competing Interests: Declaration of competing interest None of the authors have any conflicts of interest related to this manuscript to disclose., (Copyright © 2024. Published by Elsevier Ltd.)

Background and Purpose: Quantitative susceptibility mapping has been proposed to assess intraplaque hemorrhage (IPH) in the carotid artery. The purpose of this study was to compare the diagnostic accuracy of preoperative quantitative susceptibility mapping with that of the conventional T1-weighed 3D-FSE sequence for detecting IPH in cervical ICA stenosis in patients undergoing carotid endarterectomy by using histology as the reference standard., Materials and Methods: Carotid T1-weighted 3D-FSE and QSM images were obtained from 16 patients with cervical ICA stenosis before carotid endarterectomy. Relative signal intensity and susceptibility of the ICA were measured on 3 axial images, including the location of most severe stenosis on T1-weighted 3D-FSE and quantitative susceptibility mapping images, respectively. Three transverse sections of carotid plaques excised by carotid endarterectomy, which corresponded with images on MR imaging, were stained with H&E, antibody against glycophorin A, and Prussian blue, and the relative area of histologic IPH was calculated., Results: The correlation coefficient was significantly greater between susceptibility and relative area-histologic IPH ( ρ = 0.691) than between relative signal intensity and relative area-histologic IPH ( ρ = 0.413; P = .0259). The areas under the receiver operating characteristic curves for detecting histologic sections consisting primarily of IPH (relative area-histologic IPH > 40.7%) tended to be greater for susceptibility (0.964) than for T1WI FSE-relative signal intensity (0.811). Marginal homogeneity was observed between susceptibility and histologic sections consisting primarily of IPH ( P = .0412), but not between T1-weighted FSE-relative signal intensity and histologic sections consisting primarily of IPH ( P = .1824)., Conclusions: Pre-carotid endarterectomy quantitative susceptibility mapping detects histologic IPH in cervical ICA stenosis more accurately than preoperative T1-weighted 3D-FSE imaging., (© 2024 by American Journal of Neuroradiology.)

Abdominal hemorrhage is an important clinical disease that can be life-threatening in severe cases. Therefore, timely detection and treatment of abdominal hemorrhage is crucial for the health and safety of patients. Magnetic induction tomography is a non-invasive, nonradioactive, and non-contact electromagnetic imaging technology with potential application value for disease screening and continuous monitoring. In this paper, a simulation model of electrical impedance distribution close to the real human abdominal tissue was constructed, and based on this model, the magnetic induction tomography simulation method of internal bleeding was studied by the finite element numerical method, and the comparison was verified by phantom experiments. The eddy current density distribution inside the abdominal tissue and the magnetic induction phase data at the tissue boundary are solved, and sensitivity analysis of phase differences caused by changes in the radius and position of bleeding volume was conducted, and three sensitivity indicators were proposed. Both the simulation and phantom experiment show that when there are six types of tissues with different conductivity in the abdomen, the radius of bleeding increases from 10 to 30 mm, and the radius phase difference sensitivity index Ar increases approximately linearly monotonically. Its radius transformation sensitivity Kr is 3.0961 × 10-5°/cm. When the position of the bleeding volume changes, the sensitivity index Ax of the x-axis displacement phase difference shows a quasilinear monotonic decrease, and the x-axis displacement sensitivity Kx is -6.3744 × 10-6°/cm. The y-axis displacement phase difference sensitivity Ay index shows a quasilinear relationship and monotonically increases, with a y-axis displacement sensitivity Ky of 5.2870 × 10-4°/cm. The results indicate that the phase difference sensitivity before and after the occurrence of bleeding can be used as a quantitative monitoring indicator to monitor the occurrence and trend of intra-abdominal hemorrhage, laying the foundation for the preliminary screening and continuous monitoring of abdominal hemorrhage diseases using magnetic induction imaging., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Purpose: To evaluate patient and procedure-related factors contributing to the radiation dose, cumulative fluoroscopy time (CFT), and procedural time (PT) of Arterial Embolization (AE) for suspected active bleeding., Methods: Data on patients who underwent AE for suspected bleeding was retrospectively gathered between January 2019 and April 2022. Data collected included the dependent variables consisting of dose-area product (DAP), CFT, PT, and independent variables consisting of demographic, bleeding-specific, and procedure-specific parameters. All statistical computations were performed in SPSS statistics. The alpha value was set at 0.05., Results: Data from a total of 148 AE were collected with an average patient's age of 61.06 ± 21.57 years. Higher DAP was independently associated with male sex (p < 0.002), age ranges between 46 and 65 years (p = 0.019) and > 66 years (p = 0.027), BMI above 30 (p = 0.016), attending with less than 10 years of experience (p = 0.01), and bleeding in the abdomen and pelvis (p = 0.027). Longer CFT was independently associated with attending with less than 10 years of experience (p < 0.001), having 2 (p = 0.004) or > 3 (p = 0.005) foci of bleed, and age between 46 and 65 years (p = 0.007) and ≥ 66 years (p = 0.017). Longer PT was independently associated with attending with less than 10 years of experience (p < 0.001) and having 2 (p = 0.014) or > 3 (p = 0.005) foci of bleed., Conclusion: The interventionist experience influenced radiation dose, CFT and PT. Dose was also affected by patients' sex, age, BMI, as well as bleeding location. CFT was also affected by patients' age, and both CFT and PT were also affected by the number of bleeding foci. These findings highlight the multifaceted factors that affect radiation dose and procedural time, emphasizing the importance of interventionist expertise, patient's age, sex, BMI, location and number of bleeds., (© 2024. The Author(s), under exclusive licence to American Society of Emergency Radiology (ASER).)

Competing Interests: Competing interests: None declared.

Purpose: Intraplaque haemorrhage (IPH) is a well-known risk factor for faster plaque progression (volume increase); however, its etiology is unclear. We aimed at determining what other local plaque- and systemic factors contribute to plaque progression and to the development and progression of IPH., Methods: We examined 98 asymptomatic participants with carotid plaque using serial multi-contrast magnetic resonance imaging. We measured the percent of wall volume (%WV=100 x [wall volume] / [total vessel volume]) and measured IPH and calcification volumes. We used generalized estimating equations-based regression to analyze predictors of %WV change and new IPH while accounting for covariates (sex, age and statin use), and multiple non-independent observations per participant., Results: Total follow-up was 1.8 ± 0.8 years on average. The presence of IPH (β: 0.6 %/y, p = 0.033) and calcification (β: 1.2 %/y, p = 0.028) were each associated with faster plaque progression. New IPH, detected on a subsequent scan in 4 % of arteries that did not initially have IPH, was associated with larger calcification (odds ratio [OR]: 2.6 per 1-SD increase, p = 0.038) and higher pulse pressure (OR: 2.3 per 1-SD increase, p = 0.016). Larger calcification was associated with greater increases in pulse pressure (β: 1.4 mm Hg/y per 1-SD increase, p = 0.040)., Conclusions: IPH and calcification are each independently associated with faster plaque progression. The association of carotid calcification to increased pulse pressure and new IPH development suggests a possible mechanism by which calcification drives IPH development and plaque progression., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: We hypothesize that delayed phase imaging does not provide additional diagnostic information in patients who undergo multi-phasic CTA for suspected active bleeding., Methods: Data on patients who underwent multiphasic CTA (pre-contrast, arterial, porto-venous, and delayed phases) for suspected acute bleed were retrospectively collected between January 2019 and November 2021. CTA images were reviewed by a general radiologist, an interventional radiologist, and a body imaging radiologist independently. Each reader evaluated if delayed phase images provided additional information that would change the final impression of the CTA report. Additional information regarding bleeding location, time needed for delayed image acquisition, and radiation exposure were also obtained., Results: A total of 104 patients with CTAs were analyzed with an average age of 58 years ± 22. Studies rated with absent additional findings on delayed images were 102 (98.1%) by the interventional radiologist, 101 (97.1%) by the body imaging radiologist, and 100 (96.1%) by the general radiologist with percent agreement of 96.15% (kappa 0.54, p < 0.001). All the findings were characterized as unlikely to be clinically significant. Mean time added to complete a delayed phase images was 3.61 ± 3.4 min. The average CT dose length product (DLP) for the total exam was 3621.78 ± 2129.57 mGy.cm with delayed acquisition adding a mean DLP of 847.75 ± 508.8 mGy.cm., Conclusion: Delayed phase imaging does not provide significant additional diagnostic information in evaluating patients with suspected active bleeding but is associated with increased examination time and radiation exposure., (© 2024. The Author(s), under exclusive licence to American Society of Emergency Radiology (ASER).)

Spontaneous renal hemorrhage (SRH) is a diagnostic challenge and a significant cause of morbidity, and sometimes mortality. Early identification is essential to institute lifesaving and reno-protective interventions. In this review, we classify spontaneous renal hemorrhage by location, presentation and etiology. We also discuss the diagnostic approach to renal hemorrhage and optimum imaging modalities to arrive at the diagnosis. Finally, we review strategies to avoid missing a diagnosis of SRH and discuss the pitfalls of imaging in the presence of renal hemorrhage., (© 2024. The Author(s), under exclusive licence to American Society of Emergency Radiology (ASER).)

Objective: Patient with carotid blowout syndrome (CBS) may demonstrated non-bleeding digital subtraction angiography (DSA) without identifying pseudoaneurysm or contrast extravasation. Our objective is to evaluate the clinical outcomes for this specific subset of patients., Materials and Methods: A retrospective observational study was conducted on 172 CBS patients who received DSA for evaluation of transarterial embolization (TAE) between 2005 and 2022, of whom 19 patients had non-bleeding DSA and did not undergo TAE., Results: The age (55.2 ± 7.3 vs. 54.8 ± 11.1), male sex (17/19 vs. 135/153), tumor size (5.6 ± 2.4 vs. 5.2 ± 2.2), cancer locations were similar (P > 0.05) between both groups; except for there were more pseudoaneurysm/active bleeding (85.6% vs. 0%) and less vascular irregularity (14.4% vs. 94.7%) in the TAE group (P < 0.001). In the multivariable Cox regression model adjusting for age, sex, and tumor size, non-bleeding DSA group was independently associated with recurrent bleeding compared to TAE group (adjusted hazard ratio = 3.5, 95% confidence interval: 1.9-6.4, P < 0.001). Furthermore, the presence of vascular irregularity was associated with segmental recurrent bleeding (adjusted HR = 8.0, 95% CI 2.7-23.3, P < 0.001)., Conclusion: Patient showing non-bleeding DSA thus not having TAE had higher risk of recurrent bleeding, compared to patient who received TAE. Level of Evidence Level 4, Case Series., (© 2024. Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE).)

Background and Purpose: The objective is to demonstrate feasibility of quantitative susceptibility mapping (QSM) in autosomal dominant polycystic kidney disease (ADPKD) patients and to compare imaging findings with traditional T1/T2w magnetic resonance imaging (MRI)., Methods: Thirty-three consecutive patients (11 male, 22 female) diagnosed with ADPKD were initially selected. QSM images were reconstructed from the multiecho gradient echo data and compared to co-registered T2w, T1w, and CT images. Complex cysts were identified and classified into distinct subclasses based on their imaging features. Prevalence of each subclass was estimated., Results: QSM visualized two renal calcifications measuring 9 and 10 mm and three pelvic phleboliths measuring 2 mm but missed 24 calcifications measuring 1 mm or less and 1 larger calcification at the edge of the field of view. A total of 121 complex T1 hyperintense/T2 hypointense renal cysts were detected. 52 (43%) Cysts appeared hyperintense on QSM consistent with hemorrhage; 60 (49%) cysts were isointense with respect to simple cysts and normal kidney parenchyma, while the remaining 9 (7%) were hypointense. The presentation of the latter two complex cyst subtypes is likely indicative of proteinaceous composition without hemorrhage., Conclusion: Our results indicate that QSM of ADPKD kidneys is possible and uniquely suited to detect large renal calculi without ionizing radiation and able to identify properties of complex cysts unattainable with traditional approaches., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Microvascular injury immediately following reperfusion therapy in acute myocardial infarction (MI) has emerged as a driving force behind major adverse cardiovascular events in the postinfarction period. Although postmortem investigations and animal models have aided in developing early understanding of microvascular injury following reperfusion, imaging, particularly serial noninvasive imaging, has played a central role in cultivating critical knowledge of progressive damage to the myocardium from the onset of microvascular injury to months and years after in acute MI patients. This review summarizes the pathophysiological features of microvascular injury and downstream consequences, and the contributions noninvasive imaging has imparted in the development of this understanding. It also highlights the interventional trials that aim to mitigate the adverse consequences of microvascular injury based on imaging, identifies potential future directions of investigations to enable improved detection of disease, and demonstrates how imaging stands to play a major role in the development of novel therapies for improved management of acute MI patients., Competing Interests: Funding Support and Author Disclosures This work was funded in part by National Institutes of Health (HL133407, HL136578, and HL147133) to Dr Dharmakumar. Dr Dharmakumar has an ownership interest in Cardio-Theranostics, LLC. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Neonatal adrenal haemorrhage (NAH) is more frequently described in neonates due to their relatively larger size and increased vascularity. While most are asymptomatic, they can present with anaemia, jaundice, abdominal mass, scrotal haematoma or more severe complications such as shock and adrenal insufficiency. Scrotal haematoma seen with NAH may be mistaken for other more serious conditions causing acute scrotum. Prompt sonographic examination that includes the bilateral adrenal glands may help to detect NAH early and to avoid unnecessary interventions. Cases of NAH causing ipsilateral inguinal ecchymosis and scrotal haematoma have been reported, but contralateral haematomas are very rare. In this report, we present a unique case of a neonate with an antenatally acquired adrenal haematoma complicated with an acute peripartum rebleeding manifesting as a contralateral scrotal haematoma and inguinal ecchymosis. The NAH was treated conservatively and resolved on follow-up imaging., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Anticoagulant rodenticide toxicity is commonly encountered in veterinary practice that can result in internal bleeding. We have observed dogs with retroperitoneal hemorrhage secondary to anticoagulant rodenticide toxicity. However, abdominal radiographic changes in dogs with rodenticide toxicity have not been studied and retroperitoneal hemorrhage secondary to rodenticide toxicity has rarely been reported., Aim: The objective is to describe abdominal radiographic features of anticoagulant rodenticide toxicity and concurrent thoracic radiographic changes in dogs and cats., Methods: Dogs and cats diagnosed with rodenticide toxicity and with available abdominal radiographs were included in this retrospective analysis. Board-certified radiologists reviewed the abdominal and thoracic radiographs. Evaluation of abdominal radiographic changes included assessment of peritoneal or retroperitoneal effusion, subcutaneous hemorrhage, and internal hemorrhage of abdominal organs., Results: Fourteen dogs and two cats with confirmed rodenticide toxicity were included in the study. In dogs, retroperitoneal effusion (28.6%) was the most commonly observed abdominal radiographic change, followed by peritoneal effusion (14.3%). Thoracic radiographic changes in dogs included pleural effusion (63.6%) and mediastinal widening (63.6%) as the most common findings, followed by pulmonary hemorrhage (36.4%) and tracheal narrowing (36.4%). Subcutaneous hemorrhage or edema (9.1%) was also noted. No abdominal radiographic changes consistent with hemorrhage secondary to rodenticide toxicity were noted in the two cats., Conclusion: Based on our findings, it is suggested that rodenticide toxicity may result in retroperitoneal effusion even in the absence of thoracic disease. Therefore, abdominal radiographs may be valuable when suspecting hemorrhage due to coagulopathy. However, abdominal radiographic changes associated with rodenticide toxicity are considered rare in cats., Competing Interests: The authors declare no conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Hamartoma is a common benign tumor that usually occurs in the kidney, liver, lung, and pancreas. Large renal hamartomas may spontaneously rupture and hemorrhage, which is potentially life-threatening., Case Presentation: This report describes a 46-year-old Han Chinese female patient with multiple renal and hepatic hamartomas with rupture and hemorrhage of giant hamartoma in the left kidney. She underwent arterial embolization three times successively, and her condition was stable during the 2-year follow-up. This report includes a review of the relevant literature CONCLUSIONS: the findings in this report and previous literature suggest that arterial embolization can not only rapidly treat hamartoma hemorrhage in the acute phase but can also effectively control multiple lesions in the long term after repeated multisite arterial embolization., (© 2024. The Author(s).)

Case 1 : A 75-year-old man was emergently admitted to our hospital with a complaint of continuous bleeding from the ileal conduit. The conduit was constructed by a total pelvic resection for sigmoid colon cancer that invaded the urinary bladder 24 years ago. Swollen cutaneous mucosa was seen around the ileal conduit, but no obvious bleeding spot was observed. The contrast-enhanced computed tomographic (CT) scan and 3D visualization revealed varices extending to the abdominal wall. Percutaneous transhepatic embolization successfully stopped the bleeding, but it was needed again after two years. Case 2 : A 72-yearold man with a history of open cystectomy and ileal conduit for bladder cancer came to our hospital two years after the surgery, complaining of continuous bleeding from the conduit. The skin around the stoma site was discolored purple, but no obvious bleeding site or bloody urine was observed. The CT scan similar to Case 1 revealed varices in the ileal conduit, and percutaneous transhepatic embolization successfully stopped the bleeding, but it was needed again after five months. After that, three months passed without recurrence.

Purpose: To describe the clinical characteristics, multimodal imaging features, and anatomic basis of a distinctive pattern of deep retinal hemorrhages located in the central fovea, a presentation referred to as "central bouquet hemorrhage.", Methods: Retrospective, observational, multicenter case series of eyes with central bouquet hemorrhage. Multimodal imaging features were reviewed and analyzed., Results: Ten eyes from 10 patients (4 women and 6 men), with a mean age of 55.6 ± 21.7 years (range 25-84 years) were included. Underlying etiologies were neovascular age-related macular degeneration (40%), lacquer cracks in pathological myopia (30%), macular telangiectasia Type 2 (10%), proliferative diabetic retinopathy (10%), and ocular trauma associated with angioid streaks (10%). On ophthalmoscopy, all eyes with central bouquet hemorrhage displayed a deep retinal hemorrhage with round margins in the central fovea and associated with petaloid hemorrhages radiating in the surrounding Henle fiber layer. Cross-sectional optical coherence tomography showed a well-delineated round hyperreflective lesion involving the central foveal Henle fiber layer/outer nuclear layer in all cases. Accompanying hyperreflective hemorrhages tracking along the obliquely oriented Henle fiber layer were present in all eyes. Resolution occurred in all patients, either spontaneously (30%) or after treatment with intravitreal anti-vascular endothelial growth factor injections (70%), and was associated with partial visual acuity improvement (from 20/113 to 20/36)., Conclusion: "Central bouquet hemorrhage" is a novel descriptive term describing a characteristic round pattern of intraretinal blood in the fovea associated with Henle fiber layer hemorrhage and encountered in a spectrum of macular disease.

Iatrogenic arterial injuries are rare but well-recognised complications of spinal surgery. This paper presents a case of an iatrogenic arterial injury during a total en bloc spondylectomy resulting in significant haemorrhage and the patient's haemodynamic instability. The devastating complication was successfully treated with an emergency thoracic endovascular aortic repair via a percutaneous popliteal approach, while the patient remained in prone position. The patient had an uneventful recovery with no subsequent arterial injury or pseudoaneurysm to the access vessel., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: The aim of this study is to develop a nomogram model for predicting the occurrence of intramyocardial hemorrhage (IMH) in patients with Acute Myocardial Infarction (AMI) following Percutaneous Coronary Intervention (PCI). The model is constructed utilizing clinical data and the SYNTAX Score (SS), and its predictive value is thoroughly evaluated., Methods: A retrospective study was conducted, including 216 patients with AMI who underwent Cardiac Magnetic Resonance (CMR) within a week post-PCI. Clinical data were collected for all patients, and their SS were calculated based on coronary angiography results. Based on the presence or absence of IMH as indicated by CMR, patients were categorized into two groups: the IMH group (109 patients) and the non-IMH group (107 patients). The patients were randomly divided in a 7:3 ratio into a training set (151 patients) and a validation set (65 patients). A nomogram model was constructed using univariate and multivariate logistic regression analyses. The predictive capability of the model was assessed using Receiver Operating Characteristic (ROC) curve analysis, comparing the predictive value based on the area under the ROC curve (AUC)., Results: In the training set, IMH post-PCI was observed in 78 AMI patients on CMR, while 73 did not show IMH. Variables with a significance level of P < 0.05 were screened using univariate logistic regression analysis. Twelve indicators were selected for multivariate logistic regression analysis: heart rate, diastolic blood pressure, ST segment elevation on electrocardiogram, culprit vessel, symptom onset to reperfusion time, C-reactive protein, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, creatine kinase-MB, high-sensitivity troponin T (HS-TnT), and SYNTAX Score. Based on multivariate logistic regression results, two independent predictive factors were identified: HS-TnT (Odds Ratio [OR] = 1.61, 95% Confidence Interval [CI]: 1.21-2.25, P = 0.003) and SS (OR = 2.54, 95% CI: 1.42-4.90, P = 0.003). Consequently, a nomogram model was constructed based on these findings. The AUC of the nomogram model in the training set was 0.893 (95% CI: 0.840-0.946), and in the validation set, it was 0.910 (95% CI: 0.823-0.970). Good consistency and accuracy of the model were demonstrated by calibration and decision curve analysis., Conclusion: The nomogram model, constructed utilizing HS-TnT and SS, demonstrates accurate predictive capability for the risk of IMH post-PCI in patients with AMI. This model offers significant guidance and theoretical support for the clinical diagnosis and treatment of these patients., (© 2024. The Author(s).)

Competing Interests: Competing interests: None declared.

Introduction: Adrenal hemorrhage (AH) can occur due to multiple etiologies with variable radiographic appearance, often indistinguishable from underlying adrenal neoplasms. There is a lack of AH literature and evidence-based guidelines. Our study aimed to understand the prevalence and etiology of AH, follow-up, and incidence of underlying neoplasm., Methods: An institutional database was queried from January 2006 to October 2021 for patients with AH on imaging, excluding patients with known malignancies, adrenal masses, or prior adrenal surgery. Demographics, medical history, hematoma size, laterality, biochemical evaluation, intervention, and additional imaging were reviewed., Results: Of 490,301 imaging reports queried, 530 (0.11%) with AH met inclusion criteria. Most imaging (n = 485, 91.5%) was performed during trauma evaluation. Two patients underwent dedicated intervention at presentation. Interval imaging was performed in 114 (21.5%) patients at a median of 2.6 (interquartile range 0.99-13.4) mo, with resolution (n = 84, 73.7%) or decreased size of AH (n = 21, 18.4%) in most patients. Only 10 patients (1.9%) saw an outpatient provider in our system to address AH or evaluate for underlying mass, and 9 (1.7%) underwent biochemical screening. Thirteen patients (11% of 118 patients with any follow-up) had evidence of an adrenal mass, confirmed on serial imaging (n = 10) or adrenalectomy (n = 3). Scans performed for nontrauma indications were significantly more likely to have an underlying mass (n = 6/26 [23.1%]) than those performed for trauma evaluation (n = 7/92 [7.6%], P = 0.04)., Conclusions: AH is a rare finding associated with an increased rate of underlying adrenal mass, particularly when unrelated to trauma. Most AH resolves spontaneously without intervention. Follow-up imaging at 6 mo can help distinguish mass-associated AH from simple hemorrhage., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: Trauma to the pelvic ring and associated haemorrhage represent a management challenge for the multidisciplinary trauma team. In up to 10% of patients, bleeding can be the result of an arterial injury and mortality is reported as high as 89% in this cohort. We aimed to assess the mortality rate after pelvic trauma embolisation and whether earlier embolisation improved mortality., Methods: Retrospective study at single tertiary trauma and referral centre, between 1 January 2009 and 30 June 2022. All adult patients who received embolisation following pelvic trauma were included. Patients were excluded if angiography was performed but no embolisation performed., Results: During the 13.5-year time period, 175 patients underwent angiography and 28 were excluded, leaving 147 patients in the study. The all-cause mortality rate at 30-days was 11.6% (17 patients). The median time from injury to embolisation was 6.3 h (range 2.8-418.4). On regression analysis, time from injury to embolisation was not associated with mortality (OR 1.01, 95% CI 0.952-1.061). Increasing age (OR 1.20, 95% CI 1.084-1.333) and increasing injury severity score (OR 1.14, 95% CI 1.049-1.247) were positively associated with all-cause 30-day mortality, while non-selective embolisation (OR 0.11, 95% CI 0.013-0.893) was negatively associated., Conclusion: The all-cause mortality rate at 30-days in or cohort was very low. In addition, earlier time from injury to embolisation was not positively associated with all-cause 30-day mortality. Nevertheless, minimising this remains a fundamental principle of the management of bleeding in pelvic trauma., (© 2024 The Authors. Journal of Medical Imaging and Radiation Oncology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Radiologists.)

Aims: This study aims to report on safety and effectiveness of glue embolization of acute hemorrhages performed by US-guided percutaneous direct puncture, in patients where the standard endovascular approach is technically unfavourable., Methods: In this single center retrospective analysis, patients affected by traumatic or non traumatic acute hemorrhages were treated with glue embolization technically performed by US-guided direct puncture. Patients suffered from active bleeding detected at contrast-enhanced Computer Tomography and confirmed at Digital Subtracted Arteriography, with concomitant hemoglobin drop and blood pressure reduction. Six patients were reviewed; hemorrhages occurred in liver parenchima (1), gallbladder (1) and lower limbs (4). Bleedings etiologies were post-traumatic (5) and inflammatory (1); four had extraluminal blushes while 2 were pseudoaneurysms. In five cases (4 limbs and 1 hepatic bleedings) the direct-puncture approach was adopted because of technically unfavourable vascular anatomy for superselective embolization; in one case (cystic artery pseudoaneurysm), an endovascular embolization would entail a high risk of gallbladder ischemia because of its terminal arterial supply. Technical success was defined disappearance of bleeding signs at last arteriography; clinical success was considered stabilization and/or improvement of hemoglobin values and arterial pressure without additional interventions., Results: Both technical and clinical successes were obtained in 100% of the cases without major complications. No needle occlusion occurred during glue injection., Conclusions: In this study percutaneous US-guided embolization by direct puncture was a safe and effective approach to manage acute bleedings; it could be considered as an alternative in patients with unfavourable vascular anatomy for the standard catheter-directed endovascular embolization., (© 2023. Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB).)

A woman in her 80s experienced a life-threatening complication of pacemaker implant consisting of subacute right ventricular lead perforation causing iatrogenic injury to an intercostal artery, resulting in a large haemothorax. A CT scan confirmed active bleeding from the fourth intercostal artery. The patient underwent cardiothoracic surgery via a median sternotomy approach, during which the source of the bleeding was sealed, a new epicardial lead was positioned, and the original lead was extracted. This case emphasises the potentially severe consequences of pacemaker lead perforation and secondary injury to adjacent structures. It underscores the importance of early recognition and timely intervention, preferably in a tertiary specialist unit equipped for cardiothoracic surgery and confirms the value of pacemaker interrogation and CT scans for diagnosis., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To explore the feasibility of using marking and fusion image-guided technique with cone-beam CT (CBCT) in cases of kidney ruptured haemorrhage without extravascular leakage in digital subtraction angiography (DSA) images., Methods: This is a retrospective case-control study that included 43 patients who underwent transcatheter arterial embolization for kidney ruptured haemorrhage and difficult haemostasis. The patients were divided into two groups: the CBCT group (cases without extravascular leakage observed in angiography) and the control group (cases with clearly identifiable target vessels in angiography). The baseline characteristics and clinical outcomes were collected and analysed., Results: The results showed no statistically significant differences in the duration of the procedure and intraoperative blood transfusion between the control and CBCT groups (P > .05). The study clarified that the CBCT group had a significantly higher rate of improvement of gross haematuria compared to the control group (P < .05). The CBCT group showed a greater increase in haemoglobin and a lesser increase in creatinine. The clinical success rates were 87.5% in the control group and 90.9% in the CBCT group (P > .05)., Conclusions: The marking and fusion image-guided technique is useful in cases of kidney ruptured haemorrhage without extravascular leakage of contrast agent. The technique is safe, feasible, and effective, and we believe it is superior to purely DSA-guidance., Advances in Knowledge: The use of the marking and fusion image-guided technique is recommended to overcome the challenge of undetectable target vessels during interventional procedures. This technique is considered as non-inferior to purely DSA-guided interventional procedures where the target vessels are clearly identifiable., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Institute of Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Purpose: To assess the safety and clinical effectiveness of empiric embolization (EE) compared with targeted embolization (TE) in the treatment of delayed postpancreatectomy hemorrhage (PPH)., Materials and Methods: The data of patients with delayed PPH between January 2012 and August 2022 were analyzed retrospectively. In total, 312 consecutive patients (59.6 years ± 10.8; 239 men) were included. The group was stratified into 3 cohorts according to angiographic results and treatment strategies: TE group, EE group, and no embolization (NE) group. The χ 2 or Fisher exact test was implemented for comparing the clinical success and 30-day mortality. The variables related to clinical failure and 30-day mortality were identified by univariable and multivariable analyses., Results: Clinical success of transcatheter arterial embolization was achieved in 70.0% (170/243) of patients who underwent embolization. There was no statistical difference in clinical success and 30-day mortality between the EE and TE groups. Multivariate analyses demonstrated that malignant disease (odds ratio [OR] = 5.76), Grade C pancreatic fistula (OR = 7.59), intra-abdominal infection (OR = 2.54), and concurrent extraluminal and intraluminal hemorrhage (OR = 2.52) were risk factors for clinical failure. Moreover, 33 patients (13.6%) died within 30 days after embolization. Advanced age (OR = 2.59) and intra-abdominal infection (OR = 5.55) were identified as risk factors for 30-day mortality., Conclusions: EE is safe and as effective as TE in preventing rebleeding and mortality in patients with angiographically negative delayed PPH., (Copyright © 2023 SIR. Published by Elsevier Inc. All rights reserved.)

Background: To identify subjects with rupture-prone atherosclerotic plaques before thrombotic events occur is an unmet clinical need. Thus, this proof-of-concept study aims to determine which rupture-prone plaque features can be detected using clinically available photon-counting computed tomography (PCCT)., Methods: In this retrospective study, advanced atherosclerotic plaques (ex vivo, paraffin-embedded) from the Carotid Plaque Imaging Project were scanned by PCCT with reconstructed energy levels (45, 70, 120, 190 keV). Density in HU was measured in 97 regions of interest (ROIs) representing rupture-prone plaque features as demonstrated by histopathology (thrombus, lipid core, necrosis, fibrosis, intraplaque haemorrhage, calcium). The relationship between HU and energy was then assessed using a mixed-effects model for each plaque feature., Results: Plaques from five men (age 79 ± 8 [mean ± standard deviation]) were included in the study. Comparing differences in coefficients (b 1diff ) of matched ROIs on plaque images obtained by PCCT and histology confirmed that calcium was distinguishable from all other analysed features. Of greater novelty, additional rupture-prone plaque features proved discernible from each other, particularly when comparing haemorrhage with fibrous cap (p = 0.017), lipids (p = 0.003) and necrosis (p = 0.004) and thrombus compared to fibrosis (p = 0.048), fibrous cap (p = 0.028), lipids (p = 0.015) and necrosis (p = 0.017)., Conclusions: Clinically available PCCT detects not only calcification, but also other rupture-prone features of human carotid plaques ex vivo., Relevance Statement: Improved atherosclerotic plaque characterisation by photon-counting CT provides the ability to distinguish not only calcium, but also rupture-prone plaque features such as haemorrhage and thrombus. This may potentially improve monitoring and risk stratification of atherosclerotic patients in order to prevent strokes., Key Points: • CT of atherosclerotic plaques mainly detects calcium. • Many components, such as intra-plaque haemorrhage and lipids, determine increased plaque rupture risk. • Ex vivo carotid plaque photon-counting CT distinguishes haemorrhage and thrombus. • Improved plaque photon-counting CT evaluation may refine risk stratification accuracy to prevent strokes., (© 2024. The Author(s).)

Intraplaque neovascularization (IPN) is considered a leading mechanism causing carotid plaque destabilization. We provide an objective and comprehensive summary of the biology, imaging techniques, and treatment options related to carotid IPN. Plaque neovascularization has been reported to originate mainly from the adventitial vasa vasorum as a response to hypoxia. The leakage and rupture of neovessels lead to the formation of extravasations and foci of inflammation that destabilize the plaque. Vascular endothelial growth factor and its receptors are key regulators of neoangiogenesis. Neovascularization can be analyzed by advanced computed tomography and magnetic resonance imaging. The basic tools for the ultrasound assessment of IPN are contrast-enhanced ultrasound, superb microvascular imaging, and ultrasound molecular imaging. A promising direction of research seems to be the identification of patients with advanced plaque neovascularization. A simple test assessing low-velocity flow in the IPN can detect patients at risk of stroke before they experience rupture of defective neovessels and intracerebral embolism. In addition to surgical treatment, the stabilization of carotid atherosclerotic plaque can be supported pharmacologically. Statins have the best-documented role in this respect. The ideal moment of intensified therapeutic intervention in patients with previously stable carotid plaque is its increased neovascularization. However, the time frame in which intracerebral embolization may occur is unknown, and therapeutic intervention may be too late. The formation of deficient neovessels can currently be non-invasively evaluated with ultrasound. Superb microvascular imaging may change the clinical approach for asymptomatic patients at risk of cerebral ischemia., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: The management of pediatric trauma with trans-arterial embolization is uncommon, even in level 1 trauma centers; hence, there is a dearth of literature on this subject compared to the adult experience., Objective: To describe a single-center, level 1 trauma center experience with arterial embolization for pediatric trauma., Materials and Methods: A retrospective review was performed to identify demographics, transfusion requirements, pre-procedure imaging, procedural details, adverse events, and arterial embolization outcomes over a 19-year period. Twenty children (age 4.5 months to 17 years, median 13.5 years; weight 3.6 to 108 kg, median 53 kg) were included. Technical success was defined as angiographic resolution of the bleeding-related abnormality on post-embolization angiography or successful empiric embolization in the absence of an angiographic finding. Clinical success was defined as not requiring additional intervention after embolization., Results: Seventy-five percent (n=15/20) of patients required red blood cell transfusions prior to embolization with a mean volume replacement 64 ml/kg (range 12-166 ml/kg) and the median time from injury to intervention was 3 days (range 0-16 days). Technical success was achieved in 100% (20/20) of children while clinical success was achieved in 80% (n=16/20). For the 4 children (20%) with continued bleeding following initial embolization, 2 underwent repeat embolization, 1 underwent surgery, and 1 underwent repeat embolization and surgery. Mortality prior to discharge was 15% (n=3). A post-embolization mild adverse event included one groin hematoma, while a severe adverse event included one common iliac artery pseudoaneurysm requiring open surgical ligation., Conclusions: In this single-center experience, arterial embolization for hemorrhage control in children after trauma is feasible but can be challenging and the clinical failure rate of 20% in this series reflects this complexity. Standardization of pre-embolization trauma assessment parameters and embolic techniques may improve outcomes., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Carotid atherosclerotic intraplaque hemorrhage (IPH) predicts stroke. Patients with a history of stroke are treated with antiplatelet agents to prevent secondary cardiovascular events. A positive association between previous antiplatelet use and IPH was reported in a cross-sectional analysis. We investigated the changes in IPH over 2 years in patients who recently started versus those with continued antiplatelet use., Methods: In the Plaque at Risk (PARISK) study, symptomatic patients with &lt;70% ipsilateral carotid stenosis underwent carotid plaque magnetic resonance imaging (MRI) at the baseline and after 2 years to determine IPH presence and volume. Participants were categorized into new users (starting antiplatelet therapy following the index event) and continued users (previous use of antiplatelet therapy before the index event). The association between previous antiplatelet therapy and the presence of IPH at baseline MRI was investigated using multivariable logistic regression analysis. The IPH volume change over a period of 2 years, defined as the difference in volume between follow-up and baseline, was investigated in each group with a Wilcoxon signed-rank test. The IPH volume change was categorized as progression, regression, or no change. Using multivariable logistic regression, we investigated the association between new antiplatelet use and (1) newly developed ipsilateral or contralateral IPH and (2) IPH volume progression., Results: A total of 108 patients underwent carotid MRI at the baseline and follow-up. At the baseline, previous antiplatelet therapy was associated with any IPH (OR = 5.6, 95% CI: 1.3-23.1; p = 0.02). Ipsilateral IPH volume did not change significantly during the 2 years in patients who continued receiving antiplatelet agents (86.4 mm3 [18.2-235.9] vs. 59.3 mm3 [11.4-260.3]; p = 0.6) nor in the new antiplatelet users (n = 31) (61.5 mm3 [0.0-166.9] vs. 27.7 mm3 [9.5-106.4]; p = 0.4). Similar results of a nonsignificant change in contralateral IPH volume during those 2 years were observed in both groups (p &gt; 0.05). No significant associations were found between new antiplatelet use and newly developed IPH at 2 years (odds ratio [OR] = 1.0, 95% CI: 0.1-7.4) or the progression of IPH (ipsilateral: OR = 2.4, 95% CI: 0.3-19.1; contralateral: OR = 0.3, 95% CI: 0.01-8.5)., Conclusion: Although the baseline association between IPH and previous antiplatelet therapy was confirmed in this larger cohort, the new onset of antiplatelet therapy after transient ischemic attack/stroke was not associated with the newly developed IPH or progression of IPH volume over the subsequent 2 years., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Abstract: Background: After severe injury, optical measures of microvascular blood flow (MBF) decrease and do not normalize with resuscitation to normal blood pressure. These changes are associated with organ dysfunction, coagulopathy, and death. However, the pathophysiology is not well understood. Several possible pathways could also contribute to the development of trauma-induced coagulopathy (TIC). A small-animal model of trauma-related MBF derangement that persists after resuscitation and includes TIC would facilitate further study. Parametric contrast-enhanced ultrasound (CEUS) is particularly advantageous in this setting, because it noninvasively assesses MBF in large, deep vascular beds. We sought to develop such a model, measuring MBF with CEUS. Methods: Sixteen male Sprague-Dawley rats were anesthetized, ventilated, and cannulated. Rats were subjected to either no injury (sham group) or a standardized polytrauma and pressure-targeted arterial catheter hemorrhage with subsequent whole blood resuscitation (trauma group). At prespecified time points, CEUS measurements of uninjured quadriceps muscle, viscoelastic blood clot strength, and complete blood counts were taken. Results: After resuscitation, blood pressure normalized, but MBF decreased and remained low for the rest of the protocol. This was primarily driven by a decrease in blood volume with a relative sparing of blood velocity. Viscoelastic blood clot strength and platelet count also decreased and remained low throughout the protocol. Conclusion: We present a rat model of MBF derangement in uninjured skeletal muscle and coagulopathy after polytrauma that persists after resuscitation with whole blood to normal macrohemodynamics. Parametric CEUS analysis shows that this change is primarily due to microvascular obstruction. This platform can be used to develop a deeper understanding of this important process., (Copyright © 2023 by the Shock Society.)

Purpose: Studies have shown that double-inversion-recovery (DIR) prepared dark-blood T2*-weighted images result in lower SNR, CNR and diagnostic accuracy for intramyocardial hemorrhage (IMH) detection compared to non-DIR-prepared (bright-blood) T2*-weighted images; however, the mechanism contributing to this observation has not been investigated and explained in detail. This work tests the hypothesis that the loss of SNR on dark-blood cardiac T2*-weighted images of IMH stems from spin-relaxation during the long RF pulses in double inversion preparation, as a result, compromising image contrast for intramyocardial hemorrhage detection., Methods: Phantom and in-vivo animal studies were performed to test the hypothesis of the study. An agar phantom was imaged with multi-gradient-echo T2* imaging protocols with and without double-inversion-recovery (DIR) preparation. Image acquisitions were placed at different delay times (TD) after DIR preparation. SNR, T2* and Coefficient of Variation (COV) were measured and compared between DIR-prepared and non-DIR-prepared images. Canines with hemorrhagic myocardial infarctions were scanned at 3.0 T with DIR-prepared (dark-blood) and non-DIR-prepared (bright-blood) T2* imaging protocols. DIR-prepared T2* images were acquired with short, medium, and long delay times (TD). SNR, CNR, intramyocardial hemorrhage (IMH) extent, T2* and COV were measured and compared between DIR-prepared T2* images with short, medium, and long delay times (TD) to non-DIR-prepared bright-blood T2* images., Results: Phantom studies confirmed the hypothesis that the SNR loss on DIR-prepared T2* images originated from signal loss during DIR preparation. SNR followed T1 recovery curve with increased delay times (TD) indicating that SNR can be recovered with longer time delay between DIR and image acquisition. Myocardial T2* values were not affected by DIR preparation but COV of T2* was elevated. Animal studies supported the hypothesis and showed that DIR-prepared T2* images with insufficient delay time (TD) had impaired sensitivity for IMH detection due to lower SNR and CNR, and higher COV., Conclusion: We conclude that lower SNR and CNR on DIR-prepared T2* images originate from signal loss during DIR preparation and insufficient recovery between DIR preparation and image acquisition. Although, the impaired sensitivity can be recovered by extending delay time (TD), it will extend the scan time. Bright-blood T2* imaging protocols should remain the optimal choice for assessment of intramyocardial hemorrhage. DIR-prepared dark-blood T2* imaging protocols should be performed with extra attention on image signal-to-noise ratio when used for intramyocardial hemorrhage detection., Competing Interests: Declaration of Competing Interest This is to certify that all authors have seen and approved the final version of the manuscript. This manuscript is the author's original work, is not under consideration anywhere else and none of its contents have been previously published. Collectively we have no conflicts of interest to report that pertain to this work., (Copyright © 2023 Elsevier Inc. All rights reserved.)