Citations

Abstract Background To utilize high spatial resolution reconstructions for cardiac imaging at energy‐integrating detector CT (EID)‐CT with comparable noise to similar reconstructions at photon‐counting detector (PCD)‐CT, methods to control EID‐CT image noise are needed. Supervised convolutional neural networks (CNN) have shown promise for denoising, but a challenge remains to efficiently create high‐quality and unbiased estimates of noise without access to dedicated software or proprietary information, such that natural noise texture is retained in CNN‐denoised CT images. Purpose This study aims to develop and test image‐based noise estimation methods that can be used to train a CNN model, and to evaluate denoising performance and noise texture preservation for EID‐CT coronary CT angiography (cCTA) images reconstructed with high‐resolution kernels. Methods U‐net CNN models were trained for denoising. To supervise training, noise‐only images were estimated directly from high‐resolution kernel (Bv59) reconstructed EID‐CT (HR EID‐CT) patient images using two different methods: subtraction of low‐ and high‐strength iterative reconstruction (IR); subtraction of adjacent image slices with the same IR strength. The noise estimates from these methods contain differing noise texture and anatomical information. Networks were trained and validated separately for three data sets: the training data from each of the two noise‐estimation methods, and a 50%–50% partition of training data between the two methods. The trained models were applied to two sets of testing data: CT images of a uniform water phantom to measure noise power spectra (NPS), and an independent cohort of seven patient cCTA HR EID‐CT exams. The denoised patient images were compared to standard resolution EID‐CT reconstructions (Bv40). As a low‐noise reference, patient images acquired on the same day with a PCD‐CT and reconstructed using a similar kernel as HR EID‐CT were used for comparison. Results Models trained with each noise‐image estimation method denoised the HR EID‐CT images by 74%–79% to achieve a comparable noise magnitude to the HR PCD‐CT images. The peak, average, and 10% peak frequencies of the NPS of the input images (6.08, 6.24, and 12.0 cm −1 ) were better approximated by the model trained on adjacent slice subtraction (6.56, 5.87, and 11.5 cm −1 ) than by the model trained on subtraction of low‐ and high‐IR images (4.64, 5.44, and 11.3 cm −1 ). In cCTA images, the IR subtraction model images retained anatomic structures from input images but resulted in undesirable salt‐and‐pepper noise texture and CT number bias. The model trained on adjacent slice subtraction images had more natural texture and no significant bias, but the model sometimes removed small anatomic structures. The model trained on the mixed training dataset preserved both noise texture and anatomy from the model inputs and enabled visualization of small structures seen in PCD‐CT images that were previously unresolved by EID‐CT. Conclusions The noise texture and anatomical accuracy in CT images denoised with an image‐based supervised CNN are greatly influenced by the characteristics and partitioning of training data. With higher‐resolution reconstructions and noise texture‐preserving deep learning denoising, the quality of cCTA images from EID‐CT can be enhanced to enable resolvability of subtle anatomy similar to PCD‐CT.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Adult Cancer Pain provide recommendations for the comprehensive management of pain in patients with cancer. This article will focus on methods for screening for pain, safe and appropriate prescription of opioid and miscellaneous analgesics, and the optimization of nonpharmacologic interventions including integrative and interventional strategies for treatment of cancer-related pain. Additionally, the NCCN Guidelines discuss methods for the safe reduction of opioids when appropriate, as well as techniques for encouraging the judicious use of opioids. The complete version of the NCCN Guidelines for Adult Cancer Pain addresses additional issues that are not covered here, including management of pain during a pain crisis, management of procedure-related pain and anxiety, pain management for cancer survivors, and the use of nonopioid and adjuvant analgesics for cancer-related pain.

OBJECTIVE Mechanical thrombectomy (MT) is well established for large-vessel occlusion (LVO) strokes, but its safety in distal and medium-vessel occlusions (DMVOs) requires further investigation. This study analyzed the relationship between procedural approaches, petechial hemorrhage (PetH), and clinical outcomes in DMVO thrombectomy, with particular attention to technical considerations and the complex interplay between tissue injury and hemorrhagic complications. METHODS A retrospective cohort study was conducted on DMVO stroke patients treated with MT at 37 stroke centers worldwide from 2016 to 2024. Patients were categorized based on follow-up imaging into those with or without PetH. Four logistic regression models analyzed the association of PetH with favorable functional outcomes (modified Rankin Scale score ≤ 2) at 90 days, early neurological improvement (≥ 4-point National Institutes of Health Stroke Scale score decrease at 24 hours), all-cause mortality, and independent determinants of PetH. Adjusted odds ratios (aORs), 95% confidence intervals, and p values were reported. RESULTS Of 1428 patients, 439 (30.7%) developed PetH. Factors independently associated with PetH were multiple thrombectomy passes (aOR 1.58, 95% CI 1.21–2.06; p = 0.001), IV thrombolysis (aOR 1.31, 95% CI 1.01–1.69; p = 0.04), and the combined use of a stent retriever with aspiration as the first-line method compared with aspiration alone (aOR 1.66, 95% CI 1.15–2.38; p = 0.007). Conversely, general anesthesia (aOR 0.55, 95% CI 0.40–0.77; p < 0.001), higher Alberta Stroke Program Early CT Scores (aOR 0.76, 95% CI 0.69–0.83; p < 0.001), and successful recanalization (aOR 0.56, 95% CI 0.39–0.80; p = 0.002) were significantly associated with a lower odds of PetH. PetH was associated with a decreased odds of favorable functional outcomes (aOR 0.51, 95% CI 0.36–0.73; p < 0.001), reduced early neurological improvement (aOR 0.59, 95% CI 0.44–0.79; p < 0.001), and increased all-cause mortality (aOR 1.84, 95% CI 1.23–2.76; p < 0.001). CONCLUSIONS PetH is a frequent sequela following MT in DMVO strokes and is associated with poorer outcomes, likely reflecting underlying ischemic injury rather than direct causation. Procedural factors influence PetH risk, suggesting medical treatment as first-line therapy for DMVOs, with MT reserved for refractory cases using less aggressive approaches.

Pneumocystis pneumonia (PCP) is a serious fungal infection affecting immunocompromised hosts. Decompensated cirrhosis leads to cirrhosis-associated immune dysfunction (CAID), a form of impaired cellular immunity that may predispose patients to opportunistic infections such as PCP. We conducted a retrospective review of 727 patients with proven or probable PCP from 2017 to 2025. Of these, 33 had decompensated cirrhosis. These patients were stratified into two groups: Cirrhosis Only (n = 16) and Cirrhosis with Additional Immunocompromising Conditions (n = 17). Among the patients with cirrhosis, the overall mortality was 48%, with the 90-day mortality reaching 57.6% (95% CI: 39.2–74.5%). Compared with those without cirrhosis, the patients with cirrhosis had a higher risk of mortality (OR: 4.08, 95% CI: 2.01–8.30, p < 0.001), increased intensive care unit (ICU) admission (87% vs. 42%, p < 0.001), and greater need for renal replacement therapy (54.6% vs. 7.5%, p < 0.001). These findings suggest that decompensated cirrhosis alone may represent a sufficient and underrecognized risk factor for PCP, with a high associated mortality. Given the preventable nature of this infection, future studies are needed to assess the incidence, define the risk, and investigate the role of prophylaxis in this vulnerable population.

Purpose: In 2022, the American Board of Physical Medicine and Rehabilitation (ABPMR) contracted with Professional Services Industries LLC to complete a Pediatric Rehabilitation Medicine (PRM) practice analysis. The goal was to develop an updated examination content outline that accurately depicts the knowledge and skills expected for a competent PRM physician following completion of training. The purpose of this paper is to describe the process of practice analysis and to present candidate perceptions of scope of practice and relevancy of content from the first two examinations in which the new outline was applied. Methods: The practice analysis process was undertaken in four distinct stages: subject matter expert meetings to determine the tasks and knowledge areas; the development, issuance and analysis of a national survey; development of exam specifications; and results verification. Results were analyzed by a psychometrician and team to determine mean relative importance of task and knowledge items. A new outline was then created and used for the administration of the 2023 and 2024 ABPMR PRM Certification Examinations. Results: All active board certified PRM physicians identified were sent surveys via e-mail. One hundred ninety six (61.1%) respondents completed the survey. The top five task statements in order of perceived importance were performing history and physical examinations, managing muscle and tone abnormalities, prescribing orthoses and equipment, prescribing therapy services, and making appropriate specialty care referrals. The top five knowledge statements in order of perceived importance were cerebral palsy, spinal cord injury, abnormal growth and development, neuromuscular disorders, and musculoskeletal conditions. The new PRM Examination content outline created included six domains and 22 subdomains of knowledge content areas. A higher percentage of initial certification candidates sitting for the 2023 and 2024 ABPMR PRM Certification Examinations selected “Strongly Agree” or “Agree” when responding to the examination content reflecting both scope of training and relevancy. Conclusion: A practice analysis process was undertaken resulting in a new content outline for the ABPMR PRM Certification Examination. Following the implementation of the new content outline, initial certification candidate survey responses showed improved favorability regarding content reflecting scope of training and relevancy.

Sympathetic control of human blood pressure is mechanistically regulated by α 2 -adrenergic receptors distributed throughout the nervous system and cardiovascular end-targets. Recently, we discovered the sympathoinhibitory effects of central α 2 -adrenergic mechanisms on human sympathetic neuronal emission patterns. However, our knowledge remains incomplete regarding the impact of α 2 -adrenergic mechanisms on beat-by-beat transduction of muscle sympathetic nerve activity (MSNA) bursts to changes in blood pressure and heart rate (HR). Based on evidence of α 2 -adrenergic receptors within central and peripheral sympathetic neural sites and on the vasculature, this study tested the hypothesis that activation of α 2 -adrenergic receptors with dexmedetomidine (DEX) would reduce sympathetic transduction to blood pressure. In eight healthy participants (5 females; 28 ± 7 years), diastolic blood pressure (DBP; brachial arterial catheter), HR (ECG), and MSNA (peroneal microneurography) were recorded during a 5-minute supine baseline (BSL) and an intravenous DEX infusion consisting of a loading dose (10 minutes at 0.225 μg/kg/hr) and a maintenance dose (~0.15 μg/kg/hr). Signal averaging quantified sympathetic transduction to DBP and HR for 12 cardiac cycles following integrated MSNA bursts. We also quantified sympathetic transduction to DBP using a transduction gain estimate derived from the slope of the linear relationship between the peak DBP response and the number of cardiac cycles until peak DBP response. Data (mean ± SD) are reported for the 5-minute BSL and the last 5-minute period during the DEX infusion. Mixed-effects modeling and t -tests were performed. Non-parametric tests were performed for non-normally distributed data. DEX reduced resting MAP (BSL: 92 ± 7, DEX: 82 ± 6 mmHg: p < 0.001) but did not affect resting HR (BSL: 62 ± 14, DEX: 61 ± 14 bpm; p = 0.853). DEX reduced resting integrated MSNA burst frequency (BSL: 14 ± 6, DEX: 4 ± 3 bursts/min; p = 0.001) and total integrated MSNA (BSL: 663 ± 252, DEX: 188 ± 142 AU/min; p < 0.001). DEX attenuated the DBP transduction response, particularly for the cardiac cycle associated with peak DBP during BSL (cardiac cycle 6: BSL: 4.3 ± 3.2, DEX: 3.3 ± 2.0 mmHg; p = 0.025) and prolonged the time to peak DBP transduction (BSL: 6 ±1, DEX: 10 ± 3 cardiac cycles; p = 0.014). Also, DEX reduced DBP transduction gain (BSL: 1.6 ± 2.4, DEX: 0.9 ± 1.3 mmHg/cardiac cycle; p = 0.029). By contrast, DEX did not affect the mean transduction of MSNA bursts to changes in HR (BSL: 3.2 ± 3.1, DEX: 3.9 ± 4.6 mmHg; p = 0.668). These data suggest that α 2 -adrenergic mechanisms distributed among central and peripheral sympathetic neural regions and the cardiovascular system influence moment-to-moment sympathetic regulation of blood pressure homeostasis, but not HR, in humans. This work was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) and the National Institutes of Health (NIH). This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Biological sex impacts baroreflex control of integrated muscle sympathetic nerve activity (MSNA), yet our knowledge remains incomplete regarding sex differences in baroreflex regulation of the differently sized APs contributing to variations in MSNA burst frequency and size. We hypothesized that sex differences in baroreflex control of sympathetic action potential (AP) discharge contribute to higher resting AP activity in males compared to females. We measured diastolic blood pressure (DBP; Finometer or brachial arterial catheter) and MSNA (peroneal microneurography and continuous wavelet transform, APs normalized to 10 clusters) in 24 healthy individuals (aged 18-30, 12 females) during a 5-minute supine baseline. Sympathetic AP baroreflex threshold gain was measured as the slope of the linear relationship between AP discharge probability and DBP. Sympathetic AP baroreflex sensitivity gain was measured as the slope of the linear relationship between AP clusters per burst and DBP. Analyses were performed during DBP rises and falls to explore baroreflex hysteresis. Mixed-effects analyses and t-tests were performed. Data are reported as mean ± SD. In the aggregate cohort, baroreflex control of medium-sized APs exhibited hysteresis. Compared to rises in DBP, DBP falls were associated with greater AP firing probabilities (cluster 3; DBP rise: 20 ± 11, DBP fall: 26 ± 12%; p < 0.01) and greater AP baroreflex gains (cluster 3; DBP rise: -4.36 ± 2.43, DBP fall: -5.32 ± 3.09 %/mmHg; p < 0.01). In the aggregate cohort, baroreflex hysteresis was not detected for small- or large-sized AP clusters (both p ≥ 0.56). Similar observations were detected for medium-sized APs in male (M) and female (F) cohorts when analyses were stratified by sex. Compared to females, males exhibited greater medium-sized AP firing probabilities during DBP rises (cluster 3; M: 23 ± 12, F: 16 ± 8%; p < 0.01) and falls (cluster 3; M: 32 ± 13, F: 20 ± 8%; p < 0.01). However, AP baroreflex gains were not different between sexes during DBP rises (cluster 3; M: -4.87 ± 2.05, F: -3.84 ± 2.75%/mmHg; p = 0.13) and falls (cluster 3; M: -5.87 ± 2.25, F: -4.76 ± 3.77 %/mmHg; p = 0.15). In the aggregate cohort, the number of AP clusters per burst and the AP baroreflex sensitivity gain were not different between rises and falls in DBP. However, compared to females, males demonstrated a greater number of AP clusters per burst during DBP rises (M: 4 ± 0.9, F: 3 ± 0.6 clusters/burst; p < 0.01) and falls (M: 4 ± 0.8, F: 3 ± 0.7 clusters/burst; p < 0.01). No sex differences in AP baroreflex sensitivity gain were detected during DBP rises (M: -0.08 ± 0.09, F: -0.30 ± 0.07 clusters/burst/mmHg; p = 0.14) or falls (M: -0.08 ± 0.08, F: -0.02 ± 0.08 clusters/burst/mmHg; p = 0.09). These data suggest that 1) hysteresis exists in baroreflex regulation of medium-sized but not small or large sympathetic APs firing under baseline conditions and 2) in line with earlier integrated MSNA studies, compared to females, males demonstrate greater resting sympathetic outflow from greater sympathetic AP discharge and more AP clusters firing per burst in periods of rising and falling DBPs. This work was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) and the National Institutes of Health (NIH). This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

OBJECTIVE Coexisting medical conditions are increasingly prevalent in surgical populations. The impact of multiple comorbidities on patient-reported outcomes (PROs) and endotypes of frequently co-occurring conditions for cervical spondylotic myelopathy (CSM) remain unclear. This study explores whether CSM patients with multimorbidity have worse baseline and postoperative PROs and less functional improvement after surgery compared to those with few or no comorbidities. The authors also investigated whether distinct comorbidity endotypes exist among CSM surgical patients and whether they influence postoperative outcomes. METHODS The prospective Quality Outcomes Database (QOD) was used to assess patients undergoing surgery for CSM. Multimorbidity was defined as ≥ 2 chronic conditions, including diabetes, coronary artery disease, peripheral vascular disease, arthritis, chronic renal disease, chronic obstructive pulmonary disease, Parkinson’s disease, multiple sclerosis, depression, and anxiety. Baseline characteristics and 24-month PROs were assessed across multiple-comorbidity status, including modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), visual analog scale for neck and arm pain, EQ-5D, and patient satisfaction scores. Clusters were identified from the full cohort using k-medoids, revealing subgroups with similar comorbidity endotypes. RESULTS The final cohort included 1141 CSM patients (83.1% reaching 24-month follow-up), with 761 (66.7%) having 0 or 1 comorbidity and 380 (33.3%) ≥ 2 comorbidities. The multimorbidity cohort was older (mean age 62.6 ± 11.2 vs 59.5 ± 12.0 years, p < 0.001), more likely to be female (52.9% vs 44.7%, p = 0.011), and had a higher BMI (mean 31.1 ± 6.7 vs 29.7 ± 6.2 kg/m 2 , p < 0.001). Multimorbidity patients exhibited worse mJOA, NDI, and EQ-5D scores at baseline and 24 months (p < 0.05). On multivariable analysis, the total number of comorbidities was not significantly associated with any PRO measures. Four comorbidity clusters were identified: low burden, arthritis, diabetes, and high burden. On one-way ANOVA, the baseline mJOA score was significantly different across clusters (p = 0.003). At 24 months, the mJOA score was significantly lower in the diabetes and high-burden endotypes. Twenty-four-month score change and minimal clinically important difference (MCID) achievement of all PROs remained similar across clusters (p > 0.05). CONCLUSIONS While patients with multimorbidity have worse baseline and postoperative PROs, they achieve similar functional and pain-related improvements following CSM surgery. Similarly, the comorbidity endotypes identified in this QOD cohort suggest that certain patterns of coexisting chronic conditions, such as overlapping diabetes and arthritis, are associated with different levels of disability but may not diminish the effectiveness of surgical intervention.