Comparison of cerebral oxygen extraction fraction using ASE and TRUST methods in patients with sickle cell disease and healthy controls.

Abnormal oxygen extraction fraction (OEF), a putative biomarker of cerebral metabolic stress, may indicate compromised oxygen delivery and ischemic vulnerability in patients with sickle cell disease (SCD). Elevated OEF was observed at the tissue level across the brain using an asymmetric spin echo (ASE) MR method, while variable global OEFs were found from the superior sagittal sinus (SSS) using a T2-relaxation-under-spin-tagging (TRUST) MRI method with different calibration models. In this study, we aimed to compare the average ASE-OEF in the SSS drainage territory and TRUST-OEF in the SSS from the same SCD patients and healthy controls. 74 participants (SCD: N = 49; controls: N = 25) underwent brain MRI. TRUST-OEF was quantified using the Lu-bovine, Bush-HbA and Li-Bush-HbS models. ASE-OEF and TRUST-OEF were significantly associated in healthy controls after controlling for hematocrit using the Lu-bovine or the Bush-HbA model. However, no association was found between ASE-OEF and TRUST-OEF in patients with SCD using either the Bush-HbA or the Li-Bush-HbS model. Plausible explanations include a discordance between spatially volume-averaged oxygenation brain tissue and flow-weighted volume-averaged oxygenation in SSS or sub-optimal calibration in SCD. Further work is needed to refine and validate non-invasive MR OEF measurements in SCD.

Centrifuge-Simulated Spaceflight After Aortic Valve Replacement and Atrial Septal Defect Repair.

INTRODUCTION: Human access to space is expanding rapidly in the commercial environment, with various private companies offering commercial flights to spaceflight participants (SFPs). SFPs are more likely than career astronauts to have medical conditions novel to spaceflight and may not have undergone as rigorous a medical screening process as that used for career astronauts, representing new and unstudied risks in the spaceflight environment. We report participation of a subject with recent median sternotomy for aortic valve replacement and atrial septal defect closure in centrifuge-simulated dynamic phases of orbital and suborbital spaceflight.CASE REPORT: A 40-yr-old man with a history of congenital bicuspid aortic valve and atrial septal defect with successful repair 8 mo prior participated in an ongoing human centrifuge research study. The subject had the opportunity to participate in up to five centrifuge runs in an 8-h period, with profiles simulating commercial spaceflight. Maximum exposures included +4.0 Gz, +4.5 Gx, 6.1 G resultant, and maximum onset rate < 0.5 Gz · s-1 and +1 Gx · s-1. Physiological data acquisition included hemodynamics, electrocardiogram, neurovestibular exams, and postrun questionnaires covering motion sickness, disorientation, and similar. The subject tolerated the physiological aspects of hypergravity well, noting progressive sternal pain with increasing +Gx, ultimately leading him to opt out of the final profile.DISCUSSION: Postcardiothoracic surgery risks to SFPs are largely unknown, especially within 12 mo of a significant surgical procedure. This case provides an approach for risk stratification, preparticipation evaluation, and medical management of a postsurgical patient with significant cardiac history in spaceflight and analog environments.Fernandez WL, Blue RS, Harrison MF, Powers W, Shah R, Auñón-Chancellor S. Centrifuge-simulated spaceflight after aortic valve replacement and atrial septal defect repair. Aerosp Med Hum Perform. 2024; 95(2):123-131.

Word differences in news media of lower and higher peace countries revealed by natural language processing and machine learning.

Language is both a cause and a consequence of the social processes that lead to conflict or peace. "Hate speech" can mobilize violence and destruction. What are the characteristics of "peace speech" that reflect and support the social processes that maintain peace? This study used existing peace indices, machine learning, and on-line, news media sources to identify the words most associated with lower-peace versus higher-peace countries. As each peace index measures different social properties, they can have different values for the same country. There is however greater consensus with these indices for the countries that are at the extremes of lower-peace and higher-peace. Therefore, a data driven approach was used to find the words most important in distinguishing lower-peace and higher-peace countries. Rather than assuming a theoretical framework that predicts which words are more likely in lower-peace and higher-peace countries, and then searching for those words in news media, in this study, natural language processing and machine learning were used to identify the words that most accurately classified a country as lower-peace or higher-peace. Once the machine learning model was trained on the word frequencies from the extreme lower-peace and higher-peace countries, that model was also used to compute a quantitative peace index for these and other intermediate-peace countries. The model successfully yielded a quantitative peace index for intermediate-peace countries that was in between that of the lower-peace and higher-peace, even though they were not in the training set. This study demonstrates how natural language processing and machine learning can help to generate new quantitative measures of social systems, which in this study, were linguistic differences resulting in a quantitative index of peace for countries at different levels of peacefulness.

Extracranial-Intracranial Bypass and Risk of Stroke and Death in Patients With Symptomatic Artery Occlusion: The CMOSS Randomized Clinical Trial.

Importance: Prior trials of extracranial-intracranial (EC-IC) bypass surgery showed no benefit for stroke prevention in patients with atherosclerotic occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA), but there have been subsequent improvements in surgical techniques and patient selection. Objective: To evaluate EC-IC bypass surgery in symptomatic patients with atherosclerotic occlusion of the ICA or MCA, using refined patient and operator selection. Design, Setting, and Participants: This was a randomized, open-label, outcome assessor-blinded trial conducted at 13 centers in China. A total of 324 patients with ICA or MCA occlusion with transient ischemic attack or nondisabling ischemic stroke attributed to hemodynamic insufficiency based on computed tomography perfusion imaging were recruited between June 2013 and March 2018 (final follow-up: March 18, 2020). Interventions: EC-IC bypass surgery plus medical therapy (surgical group; n = 161) or medical therapy alone (medical group; n = 163). Medical therapy included antiplatelet therapy and stroke risk factor control. Main Outcomes and Measures: The primary outcome was a composite of stroke or death within 30 days or ipsilateral ischemic stroke beyond 30 days through 2 years after randomization. There were 9 secondary outcomes, including any stroke or death within 2 years and fatal stroke within 2 years. Results: Among 330 patients who were enrolled, 324 patients were confirmed eligible (median age, 52.7 years; 257 men [79.3%]) and 309 (95.4%) completed the trial. For the surgical group vs medical group, no significant difference was found for the composite primary outcome (8.6% [13/151] vs 12.3% [19/155]; incidence difference, -3.6% [95% CI, -10.1% to 2.9%]; hazard ratio [HR], 0.71 [95% CI, 0.33-1.54]; P = .39). The 30-day risk of stroke or death was 6.2% (10/161) in the surgical group and 1.8% (3/163) in the medical group, and the risk of ipsilateral ischemic stroke beyond 30 days through 2 years was 2.0% (3/151) and 10.3% (16/155), respectively. Of the 9 prespecified secondary end points, none showed a significant difference including any stroke or death within 2 years (9.9% [15/152] vs 15.3% [24/157]; incidence difference, -5.4% [95% CI, -12.5% to 1.7%]; HR, 0.69 [95% CI, 0.34-1.39]; P = .30) and fatal stroke within 2 years (2.0% [3/150] vs 0% [0/153]; incidence difference, 1.9% [95% CI, -0.2% to 4.0%]; P = .08). Conclusions and Relevance: Among patients with symptomatic ICA or MCA occlusion and hemodynamic insufficiency, the addition of bypass surgery to medical therapy did not significantly change the risk of the composite outcome of stroke or death within 30 days or ipsilateral ischemic stroke beyond 30 days through 2 years. Trial Registration: ClinicalTrials.gov Identifier: NCT01758614.

Layperson Physiological Tolerance and Operational Performance in Centrifuge-Simulated Spaceflight.

INTRODUCTION: Prior study has indicated that individuals of varied age, medical history, and limited-to-no experience tolerate spaceflight conditions. We sought to expand upon the understanding of layperson response to hypergravity conditions expected in commercial spaceflight by exposing subjects, following minimal training, to centrifuge-simulated, high-fidelity commercial spaceflight profiles. We further explored how these individuals perform in simulated operational activities during and following hypergravity.METHODS: Volunteer subjects participated in up to five centrifuge runs (maximum +4.0 Gz, +4.5 Gx, 6.1 G resultant; onset rate <0.5 Gz · s-1, ≤1 Gx · s-1). Profiles included two winged spacecraft simulations with sequential and combined +Gx/+Gz and two capsule simulations representing nominal +Gx launch and reentry. The final profile simulated a capsule launch abort, with a more dynamic cycling of +Gx exposures and oscillatory multi-axis exposures simulating parachutes and water motion. Touchscreen tablets were used to administer pattern-replication tasks during and after profiles.RESULTS: A total of 46 subjects participated, including 4 diabetics and 9 with cardiac disease. There was increased frequency of motion sickness, subjectively associated with capsule-type profiles, and increased termination of participation compared to prior studies. There was no association between medical history, age, sex, or motion sickness history and tolerance or noncompletion. Tablet test errors were common; accuracy and time to completion were associated with age. There was no association between any time metric or accuracy and sex.DISCUSSION: This study improves understanding of layperson tolerance in commercial spaceflight analog conditions, and the capsular profiles broaden the applicability of the findings. The frequency of task errors highlights the potential for mistakes in operational activities when performed by laypersons.Blue RS, Ong KM, Ray K, Menon A, Mateus J, Auñón-Chancellor S, Shah R, Powers W. Layperson physiological tolerance and operational performance in centrifuge-simulated spaceflight. Aerosp Med Hum Perform. 2023; 94(8):584-595.

Thromboelastography Use to Guide Resuscitation and Antivenom Administration after Gaboon Viper Bite.

The Gaboon viper (Bitis gabonica) is an exotic snake native to sub-Saharan Africa. Gaboon viper venom is an extremely toxic hemotoxin, causing severe coagulopathy and local tissue necrosis. These are not aggressive snakes and therefore bites involving humans are rare and there is not a substantial amount of literature documenting how to manage these injuries and resultant coagulopathies. We report a 29-year-old male presenting 3 hours after a Gaboon viper envenomation resulting in coagulopathy requiring massive resuscitation and multiple doses of antivenom. The patient received various blood products based on thromboelastography (TEG) and also underwent early continuous renal replacement therapy (CRRT) to assist in correction of severe acidosis and acute renal failure. The combination of TEG to guide resuscitation, administration of antivenom, and early implementation of CRRT allowed our team to correct venom-induced consumptive coagulopathy and ultimately allow the patient to survive following this extremely deadly Gaboon viper envenomation.

The Trauma Activation Review Committee: Response to Undertriage During a Period of Rapid Growth at a Level II Trauma Center.

Trauma triage criteria are constantly being refined for improved identification of severely injured patients. When errors occur, they should be tracked, and triage criteria adjusted to minimize these events. Two time periods of trauma registry data at a single rural level II trauma center were retrospectively compared to evaluate demographics, injuries, and outcomes to identify triage errors. In 300 activated trauma patients during 2011, overtriage was 23% and undertriage was 3.7%. In 1035 activated trauma patients during 2019, overtriage was 20.5% and undertriage was 2.2%. Mortality decreased over time overall. In 2019, Trauma I patients were older, spent more time on the ventilator, and in the ICU (all P < .001). Trauma II patients were also older, had lower ISS, hospital days, and ventilator days (all P < .001). During rapid growth, evaluation of overtriage and undertriage can provide useful feedback for hospital staff to refine triage choices and improve patient outcomes.

Emergency General Surgery Transfers to Definitive Care: An Assessment of Patient and Systemic Factors in Appendicitis Referrals.

Patients presenting to the emergency department (ED) with an Emergency General Surgery (EGS) problem often require transfer to a tertiary facility. Issues impacting EGS mirror the same issues trauma surgery faced prior to the implementation of current trauma guidelines. This study analyzed the cost, time, and transport resource utilization of EGS patients with acute appendicitis when transferred from network hospitals to a level II trauma center. This was a retrospective study. Patients were transferred by a critical or specialty care transport team 62% of the time, although no skills performed required a critical or specialty care provider. The median time from decision to transfer to incision was 254 minutes, with an average transport time of 27 minutes. This study suggests that there is an opportunity to improve access to the operating room and to decrease resource utilization of specialty care and critical care transport for patients.

Tolerance of Centrifuge-Simulated Commercial Spaceflight in a Subject with Hemophilia A.

INTRODUCTION: With increasing engagement of commercial spaceflight participants in spaceflight activities, the evaluation of individuals with medical conditions not previously characterized in the spaceflight environment is of particular interest. Factors such as acceleration forces experienced during launch, reentry, and landing of spacecraft could pose an altered risk profile in some individuals due to known disease. Bleeding diatheses present a unique concern in the spaceflight environment given hypergravity exposure and, particularly, the potential for injury resulting from transient or impact acceleration.CASE REPORT: A 26-yr-old Caucasian man with severe hemophilia A and no detectable endogenous Factor VIII (FVIII) volunteered for participation in hypergravity exposures simulating spaceflight. His treatment regimen included 50 IU · kg-1 FVIII-Fc fusion protein intravenous administration every 96 h, with supplemental FVIII administration as needed for injury or bleeding. The subject experienced two profiles at the National Aerospace Training and Research Center (NASTAR), with maximum exposure +4.0 Gz, +4.5 Gx, 6.1 G resultant, and maximum onset rate <0.5 Gz · s-1 and +1 Gx · s-1. The subject reported no abnormal events during the profiles other than brief mild vertigo. No petechial hemorrhage, ecchymosis, or other bleeding was noted during or after profiles. Supplemental FVIII was not required before, during, or after exposure.DISCUSSION: Inherited bleeding disorders present several potential concerns that must be evaluated prior to spaceflight participation. Cautious review and management of medical history, adherence and barriers to treatment, duration of spaceflight and longitudinal management concerns, and a thorough and detailed risk/benefit assessment may provide a future pathway for inclusion of individuals with hematological disorders in commercial spaceflight.Reeves IA, Blue RS, Auñon-Chancellor S, Harrison MF, Shah R, Powers WE. Tolerance of centrifuge-simulated commercial spaceflight in a subject with hemophilia A. Aerosp Med Hum Perform. 2023; 94(6):470-474.

In vivo detection of penetrating arteriole alterations in cerebral white matter in patients with diabetes with 7 T MRI.

Cerebral small vessel disease (SVD) is responsible for primary intracerebral hemorrhages, lacunar infarcts and white matter hyperintensity in T2 weighted images. While the brain lesions attributed to small vessel disease can be characterized by conventional MRI, it remains challenging to noninvasively measure the early pathological changes of the small underlying vessels. We evaluated the feasibility of detecting alterations in white matter penetrating arterioles (PA) in patients with diabetes with ultra-high field 7 T MRI. 19 participants with diabetes mellitus (DM) and 19 age- and sex-matched healthy controls were scanned with whole brain T2 and susceptibility weighted MRI and a single slice phase contrast MRI 15 mm above the corpus callosum. The PC-MRI scans were repeated three times. PA masks were manually drawn on the first images after anonymization or automatically segmented on all three images. For each PA, lumen diameter, flow velocity and volume flow rate were derived by model-based analyses of complex difference images. Quasi-Poisson regression was performed for PA count using disease condition, age, and sex as independent variables. Linear mixed effect model analyses were performed for the other measurements using disease condition and age as fixed effect and participant pair specific disease condition as random effect. No severe radiological features of SVD were observed in T2 and susceptibility weighted images in any of the participants except for white matter hyperintensities with Fazekas score of 1 or 2 in 68% and 26% of patients and controls, respectively. The minimum diameter of visible PA was 78 µm and the majority had diameters <250 µm. Among the manually segmented PA with tilt angle less than 30o from the slice normal direction, flow velocities were lower in the DM group (1.9 ± 0.6 vs. 2.2 ± 0.6; p = 0.022), while no significant difference was observed in count, diameter, or volume flow rate. Similar results were observed in the automatically segmented PA. We also observed significantly increased diameter or decreased velocity with age in some of the scans. This study suggests that early PA alterations that are discriminative of disease state and age might be detectable in human cerebral white matter with 7 T MRI in vivo.

Youth sport specialization associated with poorer lower extremity function & pain as young adults.

OBJECTIVE: Examine the link between youth sports specialization and long-term lower extremity joint health after sports by comparing lower extremity function, pain, and history of sport-related injuries between young adults that were highly, moderately, and low specialized in youth sports. METHODS: We used a cross-sectional design, and all data was collected using an electronic survey. Our sample included N = 356 young adults who participated in a primary sport during youth and high school sports but were no longer participating in that sport as a young adult. Participants were stratified into high (n = 111), moderate (n = 119), and low (n = 126) specialization groups using a 3-criteria sport specialization questionnaire based on youth sports participation prior to high school. We compared participants current Lower Extremity Functional Scale (LEFS) score (0-80), the proportion of participants with clinically important deficits in LEFS score (≤71/80), current lower extremity (foot/ankle, knee, hip) pain scores (0-10), and history of lower extremity (foot/ankle, knee, hip) injuries between the high, moderate, and low specialization groups. RESULTS: The high specialization group reported significantly lower overall LEFS scores, and a greater proportion (40%) reported clinically important deficits in LEFS scores compared to the low specialization group (20%). The high specialization group also reported greater foot/ankle and knee pain and a greater proportion of sport-related knee injuries than the low specialization group (49% vs 25%). CONCLUSIONS: Our findings suggest that even after discontinuing sports, young adults who were highly specialized in youth sports before high school reported clinically important deficits in lower extremity function, greater foot/ankle and knee pain, and a greater history of knee injuries than young adults who were not specialized in youth sports, suggesting a possible link between youth sports specialization and long-term lower extremity health after sports.

Effects of early human immunodeficiency virus infection on cerebral white matter blood flow autoregulation.

Blood flow autoregulation in cerebral white matter was measured before and after acute nicardipine-induced changes in mean arterial pressure of 10-21% in 21 treatment naïve HIV-positive adults and 32 controls. The autoregulatory index (-% cerebral blood flow change/% mean arterial pressure change) was not different at baseline ( P  = 0.71) or after 1 year of treatment ( n  = 11, P  = 0.17). We found no autoregulatory defect to explain the increased stroke risk or the development of cerebral white damage in people with HIV.

ACR Appropriateness Criteria® Cranial Neuropathy: 2022 Update.

Cranial neuropathy can result from pathology affecting the nerve fibers at any point and requires imaging of the entire course of the nerve from its nucleus to the end organ in order to identify a cause. MRI with and without intravenous contrast is often the modality of choice with CT playing a complementary role. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Prehospital Administration of Cefazolin in Trauma Patients.

OBJECTIVE: A lack of research has become a barrier to the common use of prehospital antibiotics. The objective of this study is to further the limited research of prehospital antibiotics through evaluating the clinical impact, safety, and reliability of prehospital cefazolin administration in trauma patients. METHODS: We completed a retrospective evaluation of adult trauma patients who were transported by a single air and ground critical care transport program between January 1, 2014, and June 30 2017. Two hundred eighty-two patients received prehospital cefazolin for deep wounds or open fractures before their arrival at a single level 2 trauma center during the study period. Patient demographics, mechanism of injury, injury type, infection rate, and identification of allergic reactions to cefazolin were also collected. RESULTS: Of 278 patients in the final analysis, 35.3% (n = 98) were diagnosed with an open fracture and 58.6% (n = 163) had a deep tissue injury. Eighty-two percent of prehospital open fracture diagnoses were confirmed in the emergency department. The overall infection rate was 6%; 31.3% of patients received a second dose of cefazolin in the emergency department during the study period. No patients receiving prehospital cefazolin had allergic or anaphylactic reactions. The overadministration rate was 5% (n = 14). CONCLUSION: Prehospital providers reliably identified open fractures, and prehospital cefazolin administration was not associated with anaphylactic reactions. This study population's infection rate of open fractures caused by traumatic injury was found to be 6%, and there was a low inappropriate administration rate.

Comparison of Outcomes of Ischemic Stroke Initially Imaged With Cranial Computed Tomography Alone vs Computed Tomography Plus Magnetic Resonance Imaging.

Importance: Patients with acute ischemic stroke often undergo magnetic resonance imaging (MRI) in addition to computed tomography (CT), but its association with clinical outcomes is uncertain. Objective: To assess whether clinical outcomes of patients with acute ischemic stroke with initial CT alone were noninferior to those with additional MRI. Design, Setting, and Participants: A retrospective observational propensity score-matched cohort study of clinical outcomes at discharge and 1 year for patients hospitalized with acute ischemic stroke was conducted at an academic medical center between January 2015 and December 2017. Data collection from an electronic medical record system performed from May 2020 through January 2022 was not completely blinded. Noninferiority margins were based on the designs of previous randomized clinical trials of ischemic stroke treatments. Statistical analysis was performed in January 2022. Participants were adults hospitalized with acute ischemic stroke with admission diagnosis based on CT. Exclusion criteria were primarily missing data. From 508 eligible patients, all 123 cases with additional MRI were propensity-score matched to 123 controls without. Exposure: MRI after initial diagnosis. Main Outcomes and Measures: Death or dependence at hospital discharge (modified Rankin Scale score of 3-6) and stroke or death occurring in survivors within 1 year after discharge. Results: Among 246 participants, the median age was 68 years (IQR, 58-78.8 years) and 131 (53.0%) were men. Death or dependence at discharge occurred more often in patients with additional MRI (59 of 123 [48.0%]) than in those with CT alone (52 of 123 [42.3%]; absolute difference, 5.7%; 95% CI, -6.7% to 18.1%), meeting the -7.50% criterion for noninferiority. Stroke or death within 1 year after discharge determined for 225 of 235 (96%) survivors occurred more often in patients with additional MRI (22 of 113 [19.5%]) than in those with CT alone (14 of 112 [12.5%]; relative risk, 1.14; 95% CI, 0.86-1.50), meeting the 0.725 relative risk criterion for noninferiority. Conclusions and Relevance: This propensity score-matched cohort study of patients hospitalized with acute ischemic stroke found that a diagnostic imaging strategy of initial CT alone was noninferior to initial CT plus additional MRI with regard to clinical outcomes at discharge and at 1 year. Further research is needed to determine which patients hospitalized with acute ischemic stroke benefit from MRI.

Patient Care Alterations After Point-of-Care Laboratory Testing During Critical Care Transport.

OBJECTIVE: Point-of-care laboratory testing (POCT) is associated with a reduced time to testing results and critical decision making within emergency departments. POCT is an essential clinical assessment tool because laboratory data are used to support timely critical decisions regarding acute medical conditions onditions ; however, there is currently limited research to support the use of POCT in the critical care transport environment. Few studies have evaluated the changes in patient care that occur after POCT during critical care transport. This study aims to contribute to the limited data available correlating prehospital POCT and changes in patient care. METHODS: After institutional review board approval, a retrospective review of patients transported by a critical care transport team between October 1, 2013 and September 31, 2015 was completed. During the study period, 11,454 patients were transported, and 632 (5.51%) received POCT testing. RESULTS: Patient care changes were noted in 244 (38.6%) patient tests. The most frequent patient care alterations were ventilator settings (10.9%), electrolyte changes (10.4%), and unit bed upgrades (7.1%). POCT most frequently altered care for patients with post-cardiac arrest syndrome (64.7%), sepsis/septic shock (61.8%), diabetic ketoacidosis (54.5%), or pneumonia (49.3%). CONCLUSION: Patient care alterations occurred in 38.6% of patients undergoing POCT. Patient care was most frequently changed when patients were diagnosed with post-arrest, sepsis/septic shock, diabetic ketoacidosis, and pneumonia.

Prospective motion correction and automatic segmentation of penetrating arteries in phase contrast MRI at 7 T.

PURPOSE: To develop a prospective motion correction (MC) method for phase contrast (PC) MRI of penetrating arteries (PAs) in centrum semiovale at 7 T and to evaluate its performance using automatic PA segmentation. METHODS: Head motion was monitored and corrected during the scan based on fat navigator images. Two convolutional neural networks (CNN) were developed to automatically segment PAs and exclude surface vessels. Real-life scans with MC and without MC (NoMC) were performed to evaluate the MC performance. Motion score was calculated from the ranges of translational and rotational motion parameters. MC versus NoMC pairs with similar motion scores during MC and NoMC scans were compared. Data corrupted by motion were reacquired to further improve PA visualization. RESULTS: PA counts (NPA ) and PC and magnitude contrasts (MgC) relative to neighboring tissue were significantly correlated with motion score and were higher in MC than NoMC images at motion scores above 0.5-0.8 mm. Data reacquisition further increased PC but had no significant effect on NPA and MgC. CNNs had higher sensitivity and Dice similarity coefficient for detecting PAs than a threshold-based method. CONCLUSIONS: Prospective MC can improve the count and contrast of segmented PAs in the presence of severe motion. CNN-based PA segmentation has improved performance in delineating PAs than the threshold-based method.