Utilization and Patient-Reported Outcomes of Direct-to-Consumer Telemedicine During the First 6 Weeks of the COVID-19 Pandemic in the Largest Pediatric Ambulatory Network in New York State.

Objective: We aimed to (1) describe telemedicine utilization and usability during the first 6 weeks of the pandemic and (2) determine if usability varied by individual- or visit-level characteristics. Methods: We conducted a retrospective cohort study of ambulatory pediatric telemedicine visits occurring between March 10, 2020, and April 18, 2020, across a large academic health system. We performed manual chart review to assess individual- and visit-level characteristics and invited caregivers to respond to an adapted Telehealth Usability Questionnaire (TUQ). We used multiple logistic regression to determine predictors of high usability. Results: There were 3,197 ambulatory pediatric telemedicine visits, representing 2,967 unique patients. Patients were racially/ethnically diverse (42.5% non-Hispanic White) and primarily English-speaking (89.2%). Surveys were completed by 441 (17%) of those invited. Every item of the TUQ had agreement or strong agreement from the majority of respondents. Compared with non-Hispanic White, non-Hispanic Asian identity was associated with lower usability in three domains and overall, and non-Hispanic Black identity was associated with higher satisfaction and future use. As compared with caregivers of infants younger than 1 year, caregivers of older patients reported lower usability in the three domains. Conclusions: Telemedicine was successfully implemented across 18 ambulatory pediatric specialties in the largest health system in New York State at the onset of COVID-19, and caregivers found it usable and acceptable. Usability scores did not vary by visit-level characteristics but did vary by race/ethnicity and age. Further research is necessary to identify modifiable drivers of the patient experience, particularly in non-Hispanic Asian communities and older adolescents.

Rib-based Distraction Device Implantation Before Age 3 Associated With Higher Unplanned Rate of Return to the Operating Room.

BACKGROUND: Surgical treatment of early-onset scoliosis (EOS) with rib-based implants such as the vertical expandable prosthetic titanium rib (VEPTR) is associated with a high rate of complications including surgical site infection, skin breakdown, and implant migration. Many of these complications warrant the need for unplanned reoperations, increasing the burden on an already vulnerable patient population, and introducing the further risk of infection. To provide insight into the risks of early intervention, we investigate the relationship between initial device implantation before the age of 3 and the rate of unplanned reoperation. METHODS: A retrospective review was performed of all patients at a single institution who had undergone VEPTR insertion for EOS with at least a 2-year follow-up from 2007 to 2016. Patients were stratified into the case-cohort (0 to 2 y of age) or the comparison cohort (3 to 10 y of age) based on age at the time of device implantation. Multivariate regression accounting for age and scoliosis etiology was performed to identify factors predictive of unplanned reoperation. RESULTS: A total of 137 of 185 patients treated with VEPTR were identified with 76 (56%) undergoing at least 1 unplanned reoperation during the study time period. There were 68 and 69 patients in the age 0- to 2-year and 3- to 10-year cohorts, respectively. Patients aged 0 to 2 years underwent a higher number of total procedures compared with those aged 3 to 10 (13.1±6.5 vs. 10.6±4.8, P=0.032). A significant difference was found in the rate of unplanned reoperation between the 2 cohorts with 44 (65%) patients aged 0 to 2 and 32 (46%) patients aged 3 to 10 undergoing at least 1 unplanned reoperation (P=0.031). Binary logistic multivariate regression accounting for age and scoliosis etiology demonstrated that patients aged 0 to 2 had a significantly greater odds of undergoing an unplanned reoperation (odds ratio=3.050; 95% confidence interval: 1.285-7.241; P=0.011) compared with patients aged 3 to 10 years. CONCLUSION: Overall, EOS patients aged 0 to 2 at initial VEPTR implantation are up to 3 times higher risk of undergoing an unplanned reoperation compared with those aged 3 to 10. LEVEL OF EVIDENCE: Level III.

Can We Save the Implant: Rib-based Implant Removal Rates and Risk Factors Following Irrigation and Debridement (I&D) Surgery?

BACKGROUND: In the event of a surgical site infection, management includes surgical debridement in an attempt to treat the infection and retain the implant; however they are often unsuccessful in this regard. Although studies have described the incidence of complications, current literature does not have sufficient evidence to provide clear recommendations regarding retention versus removal of implants. This study aims to identify predictive factors associated with the need for implant removal to decrease unnecessary attempts at implant retention. METHODS: A retrospective review of early-onset scoliosis patients at a single institution treated with rib-based vertical expandable prosthetic titanium rib implants who developed infection requiring irrigation and debridement (I&D) due to wound problems including surgical site infection, skin slough, and wound dehiscence. All patients had a minimum of a 2-year follow-up. Univariate and multivariate logistic regression analyses were conducted to determine the odds of implant removal. RESULTS: Fifty-nine of 181 patients (32%) required an I&D due to a wound problem. These patients underwent the initial implant procedure at a mean age of 4.6±3.8 years. In total, 29 patients ultimately underwent implant removal. Significant predictive factors for removal included total number of wound problems, total number of I&Ds, days from identification of wound problem to I&D procedure, days on antibiotics, total number of surgeries, presence of gastrostomy tube, and nonambulatory status (P<0.0001, 0.001, 0.095, 0.093, 0.082, 0.054, and 0.026, respectively). Multiple logistic regression results indicated a total number of wound problems [odds ratio (OR): 6.00, P=0.001], average days from identification of wound problem to I&D (OR: 1.03, P=0.039), and presence of a gastrostomy tube (OR: 5.7, P=0.07) as independent predictors for implant removal. CONCLUSIONS: Data suggests that time from the onset of signs of infection until debridement surgery inversely correlates with the ability to retain the implants. In addition, gastrostomy tube and history of previous wound infections may be predictive clinical factors for implant removal in patients with a rib-based vertical expandable prosthetic titanium rib instrumentation. Such information can be useful for clinicians in deciding on whom to attempt implant retention versus removal when a wound problem presents itself. LEVEL OF EVIDENCE: Level III.

Quantitative Dynamic Thoracic MRI: Application to Thoracic Insufficiency Syndrome in Pediatric Patients.

Background Available methods to quantify regional dynamic thoracic function in thoracic insufficiency syndrome (TIS) are limited. Purpose To evaluate the use of quantitative dynamic MRI to depict changes in regional dynamic thoracic function before and after surgical correction of TIS. Materials and Methods Images from free-breathing dynamic MRI in pediatric patients with TIS (July 2009-August 2015) were retrospectively evaluated before and after surgical correction by using vertical expandable prosthetic titanium rib (VEPTR). Eleven volumetric parameters were derived from lung, chest wall, and diaphragm segmentations, and parameter changes before versus after operation were correlated with changes in clinical parameters. Paired analysis from Student t test on MRI parameters and clinical parameters was performed to detect if changes (from preoperative to postoperative condition) were statistically significant. Results Left and right lung volumes at end inspiration and end expiration increased substantially after operation in pediatric patients with thoracic insufficiency syndrome, especially right lung volume with 22.9% and 26.3% volume increase at end expiration (P = .001) and end inspiration (P = .002), respectively. The average lung tidal volumes increased after operation for TIS; there was a 43.8% and 55.3% increase for left lung tidal volume and right lung tidal volume (P < .001 for both), respectively. However, clinical parameters did not show significant changes from pre- to posttreatment states. Thoracic and lumbar Cobb angle were poor predictors of MRI tidal volumes (chest wall, diaphragm, and left and right separately), but assisted ventilation rating and forced vital capacity showed moderate correlations with tidal volumes (chest wall, diaphragm, and left and right separately). Conclusion Vertical expandable prosthetic titanium rib operation was associated with postoperative increases in all components of tidal volume (left and right chest wall and diaphragm, and left and right lung tidal volumes) measured at MRI. Clinical parameters did not demonstrate improvements in postoperative tidal volumes. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Paltiel in this issue.

OxyR2 Modulates OxyR1 Activity and Vibrio cholerae Oxidative Stress Response.

Bacteria have developed capacities to deal with different stresses and adapt to different environmental niches. The human pathogen Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, utilizes the transcriptional regulator OxyR to activate genes related to oxidative stress resistance, including peroxiredoxin PrxA, in response to hydrogen peroxide. In this study, we identified another OxyR homolog in V. cholerae, which we named OxyR2, and we renamed the previous OxyR OxyR1. We found that OxyR2 is required to activate its divergently transcribed gene ahpC, encoding an alkylhydroperoxide reductase, independently of H2O2 A conserved cysteine residue in OxyR2 is critical for this function. Mutation of either oxyR2 or ahpC rendered V. cholerae more resistant to H2O2 RNA sequencing analyses indicated that OxyR1-activated oxidative stress-resistant genes were highly expressed in oxyR2 mutants even in the absence of H2O2 Further genetic analyses suggest that OxyR2-activated AhpC modulates OxyR1 activity by maintaining low intracellular concentrations of H2O2 Furthermore, we showed that ΔoxyR2 and ΔahpC mutants were less fit when anaerobically grown bacteria were exposed to low levels of H2O2 or incubated in seawater. These results suggest that OxyR2 and AhpC play important roles in the V. cholerae oxidative stress response.

Correlation of Pulmonary Function to Novel Radiographic Parameters of Collapsing Parasol Deformity in Spinal Muscular Atrophy.

Spinal muscular atrophy (SMA) is a neuromuscular disease with manifestations of scoliosis, pulmonary function decline, and, uniquely, collapse of the ribs. Methods to quantify rib deformity and its impact on pulmonary function are sparse. The authors propose new radiographic measurements to quantify the aspect of SMA known as collapsing parasol deformity and correlate these measurements with pulmonary function. Twenty-eight full-spine radiographs of pediatric SMA patients were measured twice by 3 independent investigators, with 2 weeks separating each measurement. Radiographic measurements, demographics, spirometry results, and assisted ventilation rating were obtained. Twenty-one patients with spirometry metrics were assessed to correlate pulmonary function and spinal measurements. The intrarater intraclass correlation coefficient (ICC) for the measurements ranged from 0.706 to 0.99, and the interrater ICC ranged from 0.64 to 0.97. Eighteen of 19 variables had ICC values greater than 0.75 for inter- and intrarater reliability. Twenty-one patients with forced expiratory volume in 1 second and forced vital capacity were assessed in terms of these measurements. Ratio of the concave hemithoracic width at T6/convex hemithoracic width at T6 (P=.004) and ratio of convex vertical rib displacement at the apical rib/concave vertical rib displacement (P=.021) were both significantly correlated with decreased pulmonary function. No significant correlation was found examining the average vertical rib displacement at the apical rib. High inter-and intrarater reliability can be obtained in a variety of spinal measurements of SMA patients. Various measurements are correlated to diminished pulmonary function, specifically variables showing asymmetric changes in the chest cavity. [Orthopedics. 2021;44(2):e287-e293.].

OFx: A method of 4D image construction from free-breathing non-gated MRI slice acquisitions of the thorax via optical flux.

PURPOSE: Since real-time 4D dynamic magnetic resonance imaging (dMRI) methods with adequate spatial and temporal resolution for imaging the pediatric thorax are currently not available, free-breathing slice acquisitions followed by appropriate 4D construction methods are currently employed. Self-gating methods, which extract breathing signals only from image information without any external gating technology, have much potential for this purpose, such as for use in studying pediatric thoracic insufficiency syndrome (TIS). Patients with TIS frequently suffer from extreme malformations of the chest wall, diaphragm, and spine, leading to breathing that is very complex, including deep or shallow respiratory cycles. Existing 4D construction methods cannot perform satisfactorily in this scenario, and most are not fully automatic, requiring manual interactive operations. In this paper, we propose a novel fully automatic 4D image construction method based on an image-derived concept called flux to address these challenges. METHODS: We utilized 25 dMRI data sets from 25 pediatric subjects with no known thoracic anomalies and 58 dMRI data sets from 29 patients with TIS where each patient had a dMRI scan before and after surgery. A time sequence of 80 slices are acquired at each sagittal location continuously at a rate of ~480 ms per slice under free-breathing conditions, with 30-40 sagittal locations across the chest for each subject depending on the thoracic size. In our approach, we first extract the breathing signal for each sagittal location based on the flux of the optical flow vector field of the body region from the image time series. Here, for each time point of respiratory phase, the net flux of the body region can be regarded as the flux going into or out of the body region, which we term Optical Flux (OFx). OFx provides a very robust representation of the real breathing motion of the thorax. OFx allows us to perform a full analysis of all respiratory cycles, extract only normal cycles in a robust manner, and map all extracted normal cycles on to one cosine respiration model for each sagittal location. Subsequently, we re-sample one normal cycle from the respiration model for each location independently. The normal cycle models associated with the different sagittal locations are finally composited to form the final constructed 4D image. RESULTS: We employ several metrics to evaluate the quality of the 4D construction results: Eie - error in locating time instants corresponding to end inspiration and end expiration; Eto - deviation from correct temporal order in each detected normal cycle; Ess - deviation in spatial smoothness; and Esc - deviation from spatial continuity as scored by a reader. The means and standard deviations of these metrics for normal subjects and TIS patients are found to be, respectively: Eie: 0.25 ± 0.05 and 0.38 ± 0.16 in units of time instance (ideal value = 0); Eto: 2.7% ± 2.3% and 1.8% ± 2% (ideal value = 0%); Ess: 0.5 ± 0.17 and 0.54 ± 0.25 in pixel units (ideal value = 0); Esc: 4.6 ± 0.48 and 4.56 ± 0.98 (score range: best = 5, worst = 1). The results show that the OFx method achieves excellent spatial and temporal continuity and its yield was 100% meaning that it successfully performed 4D construction on every data set tested. Compared to a recently published method, OFx is fully automatic requiring about 5 min of computational time per study starting from acquired dMRI scans. The method achieves high temporal and spatial continuity even on complex TIS data sets that include many abnormal respiratory cycles. CONCLUSIONS: A new 4D dMRI construction method based on the concept of optical flux is presented which is fully automatic and very robust in deriving respiratory signals purely from dynamic image sequences even when presented with complex breathing patterns due to severe disease conditions like TIS. Evaluations show that its accuracy is comparable to the variations found in manual annotations. An important characteristic of the method is that it is independent of the number of sagittal locations used in the construction process, which suggests that it is applicable to imaging techniques where data are acquired at only a few sagittal locations instead of the full width of the thorax. The method is not tied to any specific imaging modality, as demonstrated in this paper on not just dMRI but dynamic computed tomography (CT) as well.

Thoracic Quantitative Dynamic MRI to Understand Developmental Changes in Normal Ventilatory Dynamics.

BACKGROUND: A database of normative quantitative measures of regional thoracic ventilatory dynamics, which is essential to understanding better thoracic growth and function in children, does not exist. RESEARCH QUESTION: How to quantify changes in the components of ventilatory pump dynamics during childhood via thoracic quantitative dynamic MRI (QdMRI)? STUDY DESIGN AND METHODS: Volumetric parameters were derived via 51 dynamic MRI scans for left and right lungs, hemidiaphragms, and hemichest walls during tidal breathing. Volume-based symmetry and functional coefficients were defined to compare left and right sides and to compare contributions of the hemidiaphragms and hemichest walls with tidal volumes (TVs). Statistical analyses were performed to compare volume components among four age-based groups. RESULTS: Right thoracic components were significantly larger than left thoracic components, with average ratios of 1.56 (95% CI, 1.41-1.70) for lung TV, 1.81 (95% CI, 1.60-2.03) for hemidiaphragm excursion TV, and 1.34 (95% CI, 1.21-1.47) for hemichest wall excursion TV. Right and left lung volumes at end-expiration showed, respectively, a 44% and 48% increase from group 2 (8 ≤ age < 10) to group 3 (10 ≤ age < 12). These numbers from group 3 to group 4 (12 ≤ age ≤ 14) were 24% and 28%, respectively. Right and left hemichest wall TVs exhibited, respectively, 48% and 45% increases from group 3 to group 4. INTERPRETATION: Normal right and left ventilatory volume components have considerable asymmetry in morphologic features and dynamics and change with age. Chest wall and diaphragm contributions vary in a likewise manner. Thoracic QdMRI can provide quantitative data to characterize the regional function and growth of the thorax as it relates to ventilation.