Risk Factors and Outcomes Associated with Gaps in Care in Children with Congenital Heart Disease.

Adults with congenital heart disease (CHD) benefit from cardiology follow-up at recommended intervals of ≤ 2 years. However, benefit for children is less clear given limited studies and unclear current guidelines. We hypothesize there are identifiable risks for gaps in cardiology follow-up in children with CHD and that gaps in follow-up are associated with differences in healthcare utilization. Our cohort included children < 10 years old with CHD and a healthcare encounter from 2008 to 2013 at one of four North Carolina (NC) hospitals. We assessed associations between cardiology follow-up and demographics, lesion severity, healthcare access, and educational isolation (EI). We compared healthcare utilization based on follow-up. Overall, 60.4% of 6,969 children received cardiology follow-up within 2 years of initial encounter, including 53.1%, 58.1%, and 79.0% of those with valve, shunt, and severe lesions, respectively. Factors associated with gaps in care included increased drive time to a cardiology clinic (Hazard Ratio (HR) 0.92/15-min increase), EI (HR 0.94/0.2-unit increase), lesion severity (HR 0.48 for shunt/valve vs severe), and older age (HR 0.95/month if < 1 year old and 0.94/year if > 1 year old; p < 0.05). Children with a care gap subsequently had more emergency department (ED) visits (Rate Ratio (RR) 1.59) and fewer inpatient encounters and procedures (RR 0.51, 0.35; p < 0.05). We found novel factors associated with gaps in care for cardiology follow-up in children with CHD and altered health care utilization with a gap. Our findings demonstrate a need to mitigate healthcare barriers and generate clear cardiology follow-up guidelines for children with CHD.

Third-Grade Academic Performance and Episodes of Cardiac Care Among Children with Congenital Heart Defects.

Children with congenital heart defects (CHDs) are at risk for poor academic performance. The degree to which receipt of health care services is associated with adverse academic outcomes is not known. We examined the association between episodes of cardiac care and third-grade performance in children with CHD. We identified subjects between 1/1/2008 and 4/30/2012 among 5 centers in North Carolina. We classified children by CHD type and linked subjects to the state educational records. Any inpatient or outpatient cardiac encounter on a date of service was considered an encounter. We calculated the number of encounters by adding the number of inpatient or outpatient cardiac visits prior to the date of the end-of-grade (EOG) tests. We estimated the odds of failing third-grade reading or math EOG tests by episodes of care stratified at the 50th percentile, controlling for CHD type, maternal education, sex, race/ethnicity, birth weight, and gestational age. A total of 184 children had third-grade EOG scores linked to health care records. The median number of episodes of care was 4 (range: 1-60). Those with visits ˃ 50th percentile (> 4 encounters/year over the 4.3 year observation period) had 2.09 (95% CI 1.04, 4.21) greater odds of failing the math EOG compared to those ≤ 50th percentile (1-4 encounters). The third-grade math score declined by 1.5 points (P < 0.008) for every 10 episodes of care. There was no association of episodes of care on third-grade reading performance. Children with CHD with > 4 episodes of cardiac care/year may be at risk for delays in third-grade academic performance. Strategies to minimize school absenteeism may improve academic success in this population.

Impact of Prenatal Diagnosis of Critical Congenital Heart Disease on Preoperative and Postoperative Outcomes.

The objective of this study was to assess the relationship of prenatal diagnosis of critical congenital heart disease (CHD) to preoperative and postoperative patient findings. Retrospective analysis of neonates with critical CHD who underwent cardiothoracic surgery at one of four centers in North Carolina between 2008 and 2013. Surgical data collected by sites for submission to the Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) and the North Carolina CHD Lifespan Database were queried. There were 715 patients with STS records; 558 linked to the NC-CHD database. Patients with prenatal diagnosis had a lower incidence of preoperative risk factors, including need for mechanical ventilation and presence of shock. However, prenatally diagnosed patients had worse short-term outcomes, including higher operative mortality, higher incidence of select postoperative complications, and longer LOS. There was no difference in one-year mortality. Our findings are consistent with current literature which suggests that prenatal diagnosis of critical CHD is associated with a more optimized preoperative clinical status. However, we found that patients with prenatal diagnoses had less favorable postoperative outcomes. This needs to be investigated further, but may be secondary to patient-specific factors, such as CHD disease severity.

Hot Water Tuber Treatments for Management of Meloidogyne Arenaria in Caladium Cultivars.

Hot water treatment was evaluated for its efficacy in controlling Meloidogyne arenaria on caladium. Caladium tubers pre-infested with M. arenaria were immersed in hot water at 50°C for 0 min, 30 min, and 45 min before being planted into 16.5-cm pots filled with sterilized sandy soil. Two caladium cultivars Florida Sweetheart PP 8526 (SWT) and Postman Joyner (PJR), each with three tuber sizes [#3 (<1.5 inch), #1 (1.5-2.5 inch), and Jumbo (>2.5 inch)], were evaluated. Ninety days after the first shoot observation, the number of nematode eggs in roots and second-stage juveniles in soil were significantly reduced, but not eliminated, in both 30 min and 45 min treatments; the 45 min treatment had better results than the 30 min treatment. The efficacy of hot water treatment was affected by caladium cultivar, but not by tuber size. The treated PJR tubers had lower nematode numbers than those of the cultivar SWT. The difference in nematode number between the two caladium cultivars might be related to the morphological characteristics of caladium tubers, as the scale-like tissue on SWT tubers might provide refuge for root-knot nematodes from heat damage. Further research needs to be conducted on determining heat-tolerant thresholds for different Meloidogyne spp. and different caladium cultivars, which will help improve nematode management strategies for caladium growers.

Prevention of Allergic-like Reactions at Repeat CT: Steroid Pretreatment versus Contrast Material Substitution.

Background It is unclear whether steroid premedication is an effective means of preventing repeat allergic-like reactions in high-risk patients with a previous allergic-like reaction to iodinated contrast material (ICM). Purpose To compare the effectiveness of ICM substitution (ie, using iohexol in a patient with a previous iopromide reaction) with 12- and 2-hour steroid premedication for preventing repeat acute allergic-like reactions in high-risk patients. Materials and Methods This retrospective study identified all high-risk (ie, having a previous allergic-like reaction) adult and pediatric patients who underwent a contrast-enhanced CT examination at the institution from June 1, 2009, to May 9, 2017. Prophylactic treatments and repeat reactions were identified using chart review. The effectiveness of prophylactic treatments on repeat reaction rates was examined with multivariable regression models that used generalized estimating equations. Results A total of 1973 high-risk patients who underwent 4360 subsequent ICM-enhanced CT examinations were included. Of the 4360 examinations, a total of 280 allergic-like reactions occurred (6%) in 224 of the 1973 patients (11% of patients), with only 19 of 280 reactions (7%) that were more severe than the previous reaction being demonstrated. After adjustment, patients who received a different ICM with and without steroid premedication had a significantly lower rate of repeat reactions than did patients who received steroid premedication and the same ICM (same ICM and steroid premedication: 80 of 423 examinations [19%]; different ICM and no steroid premedication: 10 of 322 examinations [3%]; odds ratio [OR], 0.14 [95% CI: 0.06, 0.33]; P < .001; different ICM and steroid premedication: five of 166 patients [3%]; OR, 0.12 [95% CI: 0.04, 0.36]; P < .001). When examining the first scan only, patients who received the same ICM had a similar risk of repeat reactions regardless of whether they received steroid premedication (steroid premedication: 44 of 172 patients [26%] vs no premedication: 73 of 298 patients [25%]; OR, 1.00 [95% CI: 0.64, 1.57]; P = .99). Conclusion In this cohort, using an iodinated contrast material (ICM) substitution was more effective for preventing repeat allergic-like reactions than using steroid premedication and the same ICM that caused the previous reaction. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Davenport and Weinstein in this issue.

Acute Adverse Events Following Gadolinium-based Contrast Agent Administration: A Single-Center Retrospective Study of 281 945 Injections.

Background Acute allergic-like and physiologic reactions occur following administration of gadolinium-based contrast agents (GBCAs) for MRI examinations. Because these reactions are uncommon, it is challenging to compare reaction rates between GBCAs and to determine risk factors. Purpose To compare reaction rates between the four GBCAs gadodiamide, gadobutrol, gadobenate dimeglumine, and gadoterate meglumine, and to determine potential risk factors for reactions. Materials and Methods This retrospective study identified all intravenous GBCA injections for MRI examinations performed at a single institution from June 1, 2009, to May 9, 2017. Reactions were identified by reviewing records from the MRI technologist, MRI nursing staff, radiologist, emergency department, and provider. Reactions were classified as allergic-like or physiologic and as mild, moderate, or severe by using American College of Radiology criteria. GBCA reaction rates and other potential risk factors were examined by using multivariable regression models with generalized estimating equations. Results Analysis included a total of 158 100 patients (median age, 55 years [interquartile range, 40-67 years], 51% women) who received a total of 281 945 GBCA injections (140 645 gadodiamide, 94 109 gadobutrol, 39 138 gadobenate, and 8053 gadoterate). At multivariate analysis, gadobenate or gadobutrol had higher rates of allergic-like reactions compared with gadodiamide (gadobenate: odds ratio [OR], 3.9 [95% confidence interval {CI}: 3.0, 5.1]; P < .001; gadobutrol: OR, 2.3 [95% CI: 1.8, 2.9]; P < .001) or gadoterate (gadobenate: OR, 4.8 [95% CI: 1.0, 23]; P = .049; gadobutrol: OR, 2.8 [95% CI: 0.6, 14]; P = .20). Physiologic reactions were more frequently observed with gadoterate (OR, 7.7 [95% CI: 2.3, 25; P = .001), gadobenate (OR, 1.8 [95% CI: 1.3, 2.5; P < .001), and gadobutrol (OR, 1.6 [95% CI: 1.3, 2.1; P < .001) administration compared with gadodiamide. Six severe allergic-like reactions (three gadobutrol, three gadobenate) occurred requiring hospitalization. Patient age (P values .025 to < .001), sex (P < .001), location (P = .006), and MRI type (P = .003 and P = .006) were associated with acute reactions. Conclusion Gadobenate and gadobutrol are associated with higher rates of allergic-like reactions compared with gadodiamide or gadoterate, and gadoterate, gadobenate, and gadobutrol are associated with higher rates of physiologic reactions compared with gadodiamide. Patient sex, age, location, and MRI type correlate with acute reaction rates. © RSNA, 2019 Online supplemental material is available for this article.

Multi-column ultra-high performance liquid chromatography screening with chaotropic agents and computer-assisted separation modeling enables process development of new drug substances.

Modern process research and development can often be hampered by the tedious method development required to chromatographically resolve mixtures of chemical species with very similar physical properties. Herein, we describe a simple approach for the development and implementation of an efficient ultra-high performance liquid chromatography (UHPLC) assay that is extensively applied to the separation and analysis of multicomponent reaction mixtures of closely related pharmaceutical intermediates and impurities. Methods are optimized using multi-column and multi-solvent UHPLC screening in conjunction with chromatography simulation software (ACD Labs/LC Simulator). This approach is implemented to enable the separation, identification, mapping and control of impurities formed within the process chemistry optimization of the dimeric catalyst used in the synthesis of new drug substances. The final method utilized a sub-2 µm C18 stationary phase (2.1 mm I.D. × 50 mm length, 1.7 µm particle size ACQUITY UPLC BEH C18) with a non-conventional chaotropic mobile phase buffer (35 mM potassium hexafluorophosphate in 0.1% phosphoric acid/acetonitrile) in order to achieve baseline separation of all reaction components. The chromatographic simulation and modeling strategy served to generate 3D resolution maps with robust separation conditions that match the outcome of subsequent experimental data (overall ΔtR < 0.35%). Our multi-column UHPLC screening with computer-assisted chromatographic modeling is a great addition to the toolbox of synthetic chemists and can be a powerful tool for streamlining process chemistry optimization in organic chemistry laboratories across both academic and industrial sectors.

Serum and nutrient deprivation increase autophagic flux in intervertebral disc annulus fibrosus cells: an in vitro experimental study.

PURPOSE: The loss of nutrient supply is a suspected contributor of intervertebral disc degeneration. However, the extent to which low nutrition affects disc annulus fibrosus (AF) cells is unknown as nutrient deprivation has mainly been investigated in disc nucleus pulposus cells. Hence, an experimental study was designed to clarify the effects of limited nutrients on disc AF cell fate, including autophagy, the process by which cells recycle their own damaged components. METHODS: Rabbit disc AF cells were cultured in different media with varying serum concentrations under 5% oxygen. Cellular responses to changes in serum and nutrient concentrations were determined by measuring proliferation and metabolic activity. Autophagic flux in AF cells was longitudinally monitored using imaging cytometry and Western blotting for LC3, HMGB1, and p62/SQSTM1. Apoptosis (TUNEL staining and cleaved caspase-3 immunodetection) and cellular senescence (senescence-associated ß-galactosidase assay and p16/INK4A immunodetection) were measured. RESULTS: Markers of apoptosis and senescence increased, while cell proliferation and metabolic activity decreased under the withdrawal of serum and of nutrients other than oxygen, confirming cellular stress. Time-dependent increases in autophagy markers, including LC3 puncta number per cell, LC3-II expression, and cytoplasmic HMGB1, were observed under conditions of reduced nutrition, while an autophagy substrate, p62/SQSTM1, decreased over time. Collectively, these findings suggest increased autophagic flux in disc AF cells under serum and nutrient deprivation. CONCLUSION: Disc AF cells exhibit distinct responses to serum and nutrient deprivation. Cellular responses include cell death and quiescence in addition to reduced proliferation and metabolic activity, as well as activation of autophagy under conditions of nutritional stress. These slides can be retrieved under Electronic Supplementary Material.

Verification of a Portable Motion Tracking System for Remote Management of Physical Rehabilitation of the Knee.

Rehabilitation following knee injury or surgery is critical for recovery of function and independence. However, patient non-adherence remains a significant barrier to success. Remote rehabilitation using mobile health (mHealth) technologies have potential for improving adherence to and execution of home exercise. We developed a remote rehabilitation management system combining two wireless inertial measurement units (IMUs) with an interactive mobile application and a web-based clinician portal (interACTION). However, in order to translate interACTION into the clinical setting, it was first necessary to verify the efficacy of measuring knee motion during rehabilitation exercises for physical therapy and determine if visual feedback significantly improves the participant's ability to perform the exercises correctly. Therefore, the aim of this study was to verify the accuracy of the IMU-based knee angle measurement system during three common physical therapy exercises, quantify the effect of visual feedback on exercise performance, and understand the qualitative experience of the user interface through survey data. A convenience sample of ten healthy control participants were recruited for an IRB-approved protocol. Using the interACTION application in a controlled laboratory environment, participants performed ten repetitions of three knee rehabilitation exercises: heel slides, short arc quadriceps contractions, and sit-to-stand. The heel slide exercise was completed without feedback from the mobile application, then all exercises were performed with visual feedback. Exercises were recorded simultaneously by the IMU motion tracking sensors and a video-based motion tracking system. Validation showed moderate to good agreement between the two systems for all exercises and accuracy was within three degrees. Based on custom usability survey results, interACTION was well received. Overall, this study demonstrated the potential of interACTION to measure range of motion during rehabilitation exercises for physical therapy and visual feedback significantly improved the participant's ability to perform the exercises correctly.

General fluid/inductive reasoning battery for a high-ability population.

The validity of studies investigating interventions to enhance fluid intelligence (Gf) depends on the adequacy of the Gf measures administered. Such studies have yielded mixed results, with a suggestion that Gf measurement issues may be partly responsible. The purpose of this study was to develop a Gf test battery comprising tests meeting the following criteria: (a) strong construct validity evidence, based on prior research; (b) reliable and sensitive to change; (c) varying in item types and content; (d) producing parallel tests, so that pretest-posttest comparisons could be made; (e) appropriate time limits; (f) unidimensional, to facilitate interpretation; and (g) appropriate in difficulty for a high-ability population, to detect change. A battery comprising letter, number, and figure series and figural matrix item types was developed and evaluated in three large-N studies (N = 3,067, 2,511, and 801, respectively). Items were generated algorithmically on the basis of proven item models from the literature, to achieve high reliability at the targeted difficulty levels. An item response theory approach was used to calibrate the items in the first two studies and to establish conditional reliability targets for the tests and the battery. On the basis of those calibrations, fixed parallel forms were assembled for the third study, using linear programming methods. Analyses showed that the tests and test battery achieved the proposed criteria. We suggest that the battery as constructed is a promising tool for measuring the effectiveness of cognitive enhancement interventions, and that its algorithmic item construction enables tailoring the battery to different difficulty targets, for even wider applications.

A multi-reader in vitro study using porcine kidneys to determine the impact of integrated circuit detectors and iterative reconstruction on the detection accuracy, size measurement, and radiation dose for small (<4 mm) renal stones.

Background Detection of small renal calculi has benefitted from recent advances in computed tomography (CT) scanner design. Information regarding observer performance when using state-of-the-art CT scanners for this application is needed. Purpose To assess observer performance and the impact of radiation dose for detection and size measurement of <4 mm renal stones using CT with integrated circuit detectors and iterative reconstruction. Material and Methods Twenty-nine <4 mm calcium oxalate stones were randomly placed in 20 porcine kidneys in an anthropomorphic phantom. Four radiologists used a workstation to record each calculus detection and size. JAFROC Figure of Merit (FOM), sensitivity, false positive detections, and calculus size were calculated. Results Mean calculus size was 2.2 ± 0.7 mm. The CTDIvol values corresponding to the automatic exposure control settings of 160, 80, 40, 25, and 10 Quality Reference mAs (QRM) were 15.2, 7.9, 4.2, 2.7, and 1.3 mGy, respectively. JAFROC FOM was ≥ 0.97 at ≥ 80 QRM, ≥ 0.89 at ≥ 25 QRM, and was inferior to routine dose (160 QRM) at 10 QRM (0.72, P < 0.05). Per-calculus sensitivity remained ≥ 85% for every reader at ≥ 25 QRM. Mean total false positive detections per reader were ≤ 3 at ≥ 80 QRM, but increased substantially for two readers ( ≥ 12) at ≤ 40 QRM. Measured calculus size significantly decreased at ≤ 25 QRM ( P ≤ 0.01). Conclusion Using low dose renal CT with iterative reconstruction and ≥ 25 QRM results in high sensitivity, but false positive detections increase for some readers at very low dose levels (≤ 40 QRM). At very low doses with iterative reconstruction, measured calculus size will artifactually decrease.

Seeing What You Want to See: How Imprecise Uncertainty Ranges Enhance Motivated Reasoning.

In this article, we consider a novel criterion for evaluating representations of uncertainty ranges, namely, the extent to which a representation enhances motivated reasoning. In two studies, we show that perceptions of the distribution underlying ambiguous numerical ranges are affected by the motivations and worldviews of end users. This motivated reasoning effect remained after controlling for objective numeracy and fluid intelligence but was attenuated when the correct interpretation was made clear. We suggest that analysts and communicators explicitly consider the potential for motivated evaluation when evaluating uncertainty displays.

Susceptibility of Seven Caladium (Caladium × hortulanum) Cultivars to Meloidogyne arenaria, M. enterolobii, M. floridensis, M. incognita, and M. javanica.

There is no known root-knot nematode (Meloidogyne spp.) resistance in caladium (Caladium × hortulanum), an ornamental foliage crop grown from tubers, but cultivars have been reported to differ in their level of susceptibility. Research was conducted to assess the relative susceptibility of seven widely grown caladium cultivars to the species of Meloidogyne which occur in the southeastern United States, where caladium cultivars are commonly planted in commercial and residential landscapes. Root-knot nematode species tested were Meloidogyne arenaria, Meloidogyne enterolobii (=M. mayaguensis), Meloidogyne floridensis, Meloidogyne incognita, and Meloidogyne javanica. All of the caladium cultivars tested were susceptible to galling by all species of Meloidogyne tested; however M. javanica caused the least severe galling. Meloidogyne enterolobii produced high numbers of eggs per gram of fresh root on all cultivars tested, with cv. Freida Hemple having the highest number (14,799 eggs/g fresh root). Meloidogyne javanica also reproduced at a high level on most cultivars tested. Overall, the number of eggs of M. arenaria, M. floridensis, and M. incognita was low on all caladium cultivars tested. Meloidogyne javanica was isolated from caladium roots in high numbers regardless of the cultivar. Meloidogyne incognita had low numbers of second stage root-knot nematode juveniles (J2) isolated from soil of all cultivars. The high level of reproduction of M. enterolobii and the high rate of isolation of M. javanica from roots, as well as the low rate of isolation of M. incognita from soil, are not reflected in gall ratings where M. javanica ratings were low but high numbers of eggs and J2 were present in roots. An increased understanding of cultivar susceptibility levels and the reproductive capacity of common root-knot nematode on caladium under various environmental conditions is needed to better manage nematode-infested planting sites and improve caladium growth.

Mechanical role of the posterior column components in the cervical spine.

PURPOSE: To quantify the mechanical role of posterior column components in human cervical spine segments. METHODS: Twelve C6-7 segments were subjected to resection of (1) suprasinous/interspinous ligaments (SSL/ISL), (2) ligamenta flavum (LF), (3) facet capsules, and (4) facets. A robot-based testing system performed repeated flexibility testing of flexion-extension (FE), axial rotation (AR), and lateral bending (LB) to 2.5Nm and replayed kinematics from intact flexibility tests for each state. Range-of-motion, stiffness, moment resistance and resultant forces were calculated. RESULTS: The LF contributes largely to moment resistance, particularly in flexion. Facet joints were primary contributors to AR and LB mechanics. Moment/force responses were more sensitive and precise than kinematic outcomes. CONCLUSIONS: The LF is mechanically important in the cervical spine; its injury could negatively impact load distribution. Damage to facets in a flexion injury could lead to AR or LB hypermobility. Quantifying the contribution of spinal structures to moment resistance is a sensitive, precise process for characterizing structural mechanics.

Detection of Local Recurrence of Prostate Cancer After Radical Prostatectomy Using Endorectal Coil MRI at 3 T: Addition of DWI and Dynamic Contrast Enhancement to T2-Weighted MRI.

OBJECTIVE: The purpose of this study was to assess the utility of DWI and dynamic contrast enhancement (DCE) in MRI at 3 T with an endorectal coil in identifying local prostate cancer recurrence after radical prostatectomy. MATERIALS AND METHODS: Eighty men underwent MRI for suspected local recurrence. The reference standards were histopathologic result, decrease in prostate-specific antigen level after salvage radiation therapy, and follow-up findings. Using a 5-point scoring system, two reviewers independently interpreted T2-weighted images alone (protocol A), a combination of T2-weighted and DW images (protocol B), a combination of T2-weighted and DCE images (protocol C), and a combination of T2-weighted, DW, and DCE images (protocol D). ROC analysis was used to compare the four protocols. RESULTS: Local recurrence was found in 57 of the 80 patients (71.3%). The ROC AUCs for protocols A, B, C, and D were 0.71, 0.72, 0.90, and 0.89 for reader 1 and 0.65, 0.62, 0.84, and 0.83 for reader 2. Protocols C and D had statistically better performance than protocols A and B for both readers (p < 0.001). For local recurrence lesions with a long-axis diameter less than 10 mm visualized with protocol C, protocol B had detection rates of 25.0-29.4% and for lesions measuring 10 mm or greater, 67.9-69.0%. The rates of detection of local recurrence with protocol C or D were 76.5-82.4% for prostate-specific antigen levels less than 0.4 ng/mL, 60-73.3% for 0.4-1.0 ng/mL, and 80-88.0% for greater than 1.0 ng/mL. CONCLUSION: Addition of DCE to T2-weighted imaging in 3-T MRI with an endorectal coil improves the accuracy of detection of local cancer recurrence after radical prostatectomy. The addition of DWI is of limited incremental value for detection, especially of small lesions.

Needle puncture in rabbit functional spinal units alters rotational biomechanics.

STUDY DESIGN: An in vitro biomechanical study for rabbit lumbar functional spinal units (FSUs) using a robot-based spine testing system. OBJECTIVE: To elucidate the effect of annular puncture with a 16 G needle on mechanical properties in flexion/extension, axial rotation, and lateral bending. SUMMARY OF BACKGROUND DATA: Needle puncture of the intervertebral disk has been shown to alter mechanical properties of the disk in compression, torsion, and bending. The effect of needle puncture in FSUs, where intact spinal ligaments and facet joints may mitigate or amplify these changes in the disk, on spinal motion segment stability subject to physiological rotations remains unknown. METHODS: Rabbit FSUs were tested using a robot testing system whose force/moment and position precision were assessed to demonstrate system capability. Flexibility testing methods were developed by load-to-failure testing in flexion/extension, axial rotation, and lateral bending. Subsequent testing methods were used to examine a 16 G needle disk puncture and No. 11 blade disk stab (positive control for mechanical disruption). Flexibility testing was used to assess segmental range-of-motion (degrees), neutral zone stiffness (N m/degrees) and width (degrees and N m), and elastic zone stiffness before and after annular injury. RESULTS: The robot-based system was capable of performing flexibility testing on FSUs-mean precision of force/moment measurements and robot system movements were <3% and 1%, respectively, of moment-rotation target values. Flexibility moment targets were 0.3 N m for flexion and axial rotation and 0.15 N m for extension and lateral bending. Needle puncture caused significant (P<0.05) changes only in flexion/extension range-of-motion and neutral zone stiffness and width (N m) compared with preintervention. No. 11 blade-stab significantly increased range-of-motion in all motions, decreased neutral zone stiffness and width (N m) in flexion/extension, and increased elastic zone stiffness in flexion and lateral bending. CONCLUSIONS: These findings suggest that disk puncture and stab can destabilize FSUs in primary rotations.

Intravenous contrast material exposure is not an independent risk factor for dialysis or mortality.

PURPOSE: To determine the risk of emergent dialysis and short-term mortality following intravenous iodinated contrast material exposure. MATERIALS AND METHODS: This single-center retrospective study was HIPAA compliant and institutional review board approved. All contrast material-enhanced (contrast group) and unenhanced (noncontrast group) abdominal, pelvic, and thoracic computed tomography scans from 2000-2010 were identified. Patients in the contrast and noncontrast groups were compared following propensity score-based 1:1 matching to reduce intergroup selection bias. Patients with preexisting diabetes mellitus, congestive heart failure, or chronic or acute renal failure were identified as high-risk patient subgroups for nephrotoxicity. The effects of contrast material exposure on the rate of acute kidney injury ( AKI acute kidney injury ) (serum creatinine level ≥ 0.5 mg/dL [44.2 µmol/L] above baseline within 24-72 hours of exposure) and dialysis or death within 30 days of exposure were determined by using odds ratios ( OR odds ratio s) and covariate-adjusted Cox proportional hazards models. Results were validated with a bootstrapped sensitivity analysis. RESULTS: The 1:1 matching on the basis of the propensity score yielded a cohort of 21 346 patients (10 673 in the contrast group, 10 673 in the noncontrast group). Within this cohort, the risks of AKI acute kidney injury ( OR odds ratio , 0.94; 95% confidence interval [ CI confidence interval ]: 0.83, 1.07; P = .38), emergent dialysis ( OR odds ratio , 0.96; 95% CI confidence interval : 0.54, 1.60; P = .89), and 30-day mortality (hazard ratio [ HR hazard ratio ], 0.97; 95% CI confidence interval : 0.87, 1.06; P = .45) were not significantly different between the contrast group and the noncontrast group. Although patients who developed AKI acute kidney injury had higher rates of dialysis and mortality, contrast material exposure was not an independent risk factor for either outcome for dialysis ( OR odds ratio , 0.89; 95% CI confidence interval : 0.40, 2.01; P = .78) or for mortality ( HR hazard ratio , 1.03; 95% CI confidence interval : 0.82, 1.32; P = .63), even among patients with compromised renal function or predisposing comorbidities. CONCLUSION: Intravenous contrast material administration was not associated with excess risk of AKI acute kidney injury , dialysis, or death, even among patients with comorbidities reported to predispose them to nephrotoxicity.

Premedication of patients for prior urticarial reaction to iodinated contrast medium.

PURPOSE: The purpose of this study was to determine whether premedication of patients with a history of urticaria after low osmolality contrast media (LOCM) results in fewer subsequent reactions, and if a benefit is seen, to determine which premedication regimen results in the fewest reactions. MATERIALS AND METHODS: The subsequent contrast enhanced studies of patients who experienced urticaria after intravenous LOCM between 2002 and 2009 were reviewed to determine whether an additional reaction occurred. Patients undergoing subsequent studies received either no premedication, or premedication with diphenhydramine alone, corticosteroid alone, or corticosteroid plus diphenhydramine. Reactions occurring without premedication were termed repeat reactions and reactions occurring after premedication were termed breakthrough reactions. RESULTS: Fifty patients with a history of urticaria after LOCM met the inclusion criteria and underwent 133 subsequent contrast enhanced studies. Repeat reactions occurred in 7.6% (5/66) of subsequent studies in patients receiving no premedication. Breakthrough reactions occurred in 8% (2/25), 46% (12/26), and 44% (7/16) of subsequent studies in patients receiving premedication with diphenhydramine, corticosteroid, and corticosteroid plus diphenhydramine, respectively. All subsequent reactions consisted of urticaria as the most severe manifestation; no hemodynamic instability or respiratory compromise occurred. In multivariate analysis, premedication with corticosteroid was significantly associated with higher rate of breakthrough reaction relative to no premedication (OR 14.3, 95% CI: 4.1-50.4), as was premedication with corticosteroid plus diphenhydramine (OR 8.3, 95% CI: 1.8-37.9). CONCLUSION: The results suggest that premedication of patients with a history of urticaria after LOCM may not be necessary.

Noninvasive cardiovascular imaging.

Over the past 2 decades, use of noninvasive cardiovascular imaging has increased dramatically. This article provides a brief synopsis of the current state of several technologies-- echocardiography, cardiac magnetic resonance imaging, and cardiac computed tomography--as well as a glimpse at future possibilities in cardiac imaging.

A Classification-Based Adaptive Segmentation Pipeline: Feasibility Study Using Polycystic Liver Disease and Metastases from Colorectal Cancer CT Images.

Automated segmentation tools often encounter accuracy and adaptability issues when applied to images of different pathology. The purpose of this study is to explore the feasibility of building a workflow to efficiently route images to specifically trained segmentation models. By implementing a deep learning classifier to automatically classify the images and route them to appropriate segmentation models, we hope that our workflow can segment the images with different pathology accurately. The data we used in this study are 350 CT images from patients affected by polycystic liver disease and 350 CT images from patients presenting with liver metastases from colorectal cancer. All images had the liver manually segmented by trained imaging analysts. Our proposed adaptive segmentation workflow achieved a statistically significant improvement for the task of total liver segmentation compared to the generic single-segmentation model (non-parametric Wilcoxon signed rank test, n = 100, p-value << 0.001). This approach is applicable in a wide range of scenarios and should prove useful in clinical implementations of segmentation pipelines.