Lower Extremity Growth according to AI Automated Femorotibial Length Measurement on Slot-Scanning Radiographs in Pediatric Patients

Background Commonly used pediatric lower extremity growth standards are based on small, dated data sets. Artificial intelligence (AI) enables creation of updated growth standards. Purpose To train an AI model using standing slot-scanning radiographs in a racially diverse data set of pediatric patients to measure lower extremity length and to compare expected growth curves derived using AI measurements to those of the conventional Anderson-Green method. Materials and Methods This retrospective study included pediatric patients aged 0-21 years who underwent at least two slot-scanning radiographs in routine clinical care between August 2015 and February 2022. A Mask Region-based Convolutional Neural Network was trained to segment the femur and tibia on radiographs and measure total leg, femoral, and tibial length; accuracy was assessed with mean absolute error. AI measurements were used to create quantile polynomial regression femoral and tibial growth curves, which were compared with the growth curves of the Anderson-Green method for coverage based on the central 90% of the estimated growth distribution. Results In total, 1874 examinations in 523 patients (mean age, 12.7 years ± 2.8 [SD]; 349 female patients) were included; 40% of patients self-identified as White and not Hispanic or Latino, and the remaining 60% self-identified as belonging to a different racial or ethnic group. The AI measurement training, validation, and internal test sets included 114, 25, and 64 examinations, respectively. The mean absolute errors of AI measurements of the femur, tibia, and lower extremity in the test data set were 0.25, 0.27, and 0.33 cm, respectively. All 1874 examinations were used to generate growth curves. AI growth curves more accurately represented lower extremity growth in an external test set (n = 154 examinations) than the Anderson-Green method (90% coverage probability: 86.7% [95% CI: 82.9, 90.5] for AI model vs 73.4% [95% CI: 68.4, 78.3] for Anderson-Green method; χ2 test, P < .001). Conclusion Lower extremity growth curves derived from AI measurements on standing slot-scanning radiographs from a diverse pediatric data set enabled more accurate prediction of pediatric growth. © RSNA, 2024 Supplemental material is available for this article.

Inpatient Resource Utilization for Hypoplastic Left Heart Syndrome from Birth Through Fontan

Completing 3-stage palliation for hypoplastic left heart syndrome requires significant resources. An analysis of recent data has not been performed. We aimed to determine total charges necessary to complete all 3 stages of single-ventricle palliation, including interstage encounters. We also aimed to determine overall resource utilization, including hospital days, interstage admissions, and interstage procedures. We performed a retrospective cohort study using data from the Pediatric Health Information System database between 2016 and 2021, including all patients who completed 3-stage palliation for hypoplastic left heart syndrome. We identified 199 patients who underwent 3-stage palliation of hypoplastic left heart syndrome between 2016 and 2021. Median total adjusted charges (interquartile range, IQR) over the course of 3-stage palliation were $1,475,800 ($1,028,900-2,191,700). Median adjusted charges (IQR) for stage 1, 2, and 3 hospitalizations were $604,300 ($419,000-891,400), $234,000 ($164,300-370,800), and $256,260 ($178,300-345,900), respectively. Median hospital length of stay (IQR) for stages 1, 2, and 3 was 36 (26,53), 9 (6,17), and 10 (7,14) days, respectively. Pulmonary artery stenosis was the most common admitting diagnosis for interstage hospitalizations (3.4% of hospitalizations). Cardiac catheterization (24.1% of procedures) and feeding tube placement (10.0% of procedures) were the most common principal procedures during interstage hospitalizations. Total inpatient charges incurred throughout 3-stage palliation of hypoplastic left heart syndrome are substantial and have risen since prior studies. Gastrointestinal comorbidities and feeding optimization contribute considerably to this resource utilization.

Diagnostic Accuracy of Laryngeal Ultrasound for Evaluating Vocal Fold Movement Impairment in Children

PURPOSE

Vocal fold movement impairment (VFMI) secondary to recurrent laryngeal nerve (RLN) injury is a common source of morbidity after pediatric cervical, thoracic, and cardiac procedures. Flexible laryngoscopy (FL) is the gold standard to diagnose VFMI yet can be challenging to perform and/or risks possible clinical decompensation in some children and is an aerosolizing procedure. Laryngeal ultrasound (LUS) is a potential non-invasive alternative, but limited data exists in the pediatric surgical population regarding its efficacy. We aimed to investigate the diagnostic accuracy of LUS compared to FL in evaluating VFMI.

METHODS

A prospective, single-center, single-blinded (rater) cohort study was undertaken on perioperative pediatric patients at risk for RLN injury. Patients underwent FL and LUS. Cohen's kappa was used to determine chance-corrected agreement.

RESULTS

Between 2021 and 2023, 85 paired evaluations were performed with patients having a median (IQR) age of 10 (4, 42) months and weight of 7.5 (5.4, 13.4) kilograms. The prevalence of VFMI was 27.1%. Absolute agreement between evaluations was 98.8% (kappa 0.97, 95% CI: 0.91-1.00, P < 0.001). The sensitivity and specificity of LUS in detecting VFMI was 95.7% and 100%, yielding a positive predictive value (PPV) of 100% and negative predictive value (NPV) of 98.4% (95% CI: 90-100%). Diagnostic accuracy was 98.8% (95% CI: 93-100%).

CONCLUSION

LUS is a highly accurate modality in evaluating VFMI in children. While FL remains the gold standard for diagnosis, LUS offers a low-risk screening modality for children at risk for VFMI such that only those with an abnormal LUS or presence of clinical symptoms discordant with LUS findings should undergo FL.

TYPE OF STUDY

Prospective, single-center, single blinded (rater), cohort study.

LEVEL OF EVIDENCE

Level II.

Cancer risks from cosmic radiation exposure in flight: A review

Aircrew (consisting of flight attendants, pilots, or flight engineers/navigators) are exposed to cosmic ionizing radiation (CIR) at flight altitude, which originates from solar activity and galactic sources. These exposures accumulate over time and are considerably higher for aircrew compared to the general population, and even higher compared to U.S. radiation workers. Many epidemiological studies on aircrew have observed higher rates of specific cancers compared to the general population. Despite high levels of CIR exposure and elevated rates of cancer in aircrew, a causal link between CIR and cancer has yet to be established. Many challenges still exist in effectively studying this relationship, not the least of which is evaluating CIR exposure separately from the constellation of factors that occur as part of the flight environment. This review concentrates on cancer incidence and mortality observed among aircrew in epidemiologic studies in relation to CIR exposure and limitation trends observed across the literature. The aim of this review is to provide an updated comprehensive summary of the literature that will support future research by identifying epidemiological challenges and highlighting existing increased cancer concerns in an occupation where CIR exposure is anticipated to increase in the future.

Presentation and outcomes of post-transplant lymphoproliferative disorder at a single institution pediatric transplant center

BACKGROUND

This study aimed to characterize features present at the time of diagnosis and describe outcomes in patients with post-transplant lymphoproliferative disorder (PTLD) following pediatric solid organ transplantation.

METHODS

We performed a retrospective review of solid organ transplant patients who developed pathologically confirmed PTLD at our center from 2006 to 2016.

RESULTS

Of 594 patients included in this study, 41(6.9%) were diagnosed with PTLD. Median age at transplant was 5.6(IQR 1.7-16.1) years. Proportion of PTLD cases by organ transplanted and median time (IQR) to disease onset were: heart 11/144(7.6%) at 13.6(8.5-55.6) months, lung 7/52(13.5%) at 9.1(4.9-35) months, kidney 8/255(3.1%) at 39.5(13.9-57.1) months, liver 12/125(9.6%) at 7.7(5.5-22) months, intestine 0/4(0%), and multi-visceral 3/14(21.4%) at 5.4(5.4-5.6) months. No significant correlation was seen between recipient EBV status at transplant and timing of development of PTLD. There were six early lesions, 15 polymorphic, 19 monomorphic, and one uncharacterizable PTLD. Following immunosuppression reduction, 30 patients received rituximab, and 14 required chemotherapy. At median 25(IQR 12-53) months follow-up from the onset of PTLD, eight patients died secondary to transplant related complications, three are alive with active disease, and 30 have no evidence of disease.

CONCLUSION

PTLD is a significant complication following pediatric solid organ transplantation. EBV levels in conjunction with symptomatic presentation following transplant may assist in detection of PTLD. Most patients can achieve long-term disease-free survival through immunosuppression reduction, anti-CD20 treatment, and chemotherapy in refractory cases.

Are SER-II Ankle Fractures Anatomic? Computed Tomography Demonstrates Mortise Malalignment in the Setting of Apparently Normal Radiographs

BACKGROUND

Ankle fracture treatment is predicated on minimal displacement, leading to abnormal joint contact area. The purpose of this investigation is to determine whether computed tomography (CT) detects subtle mortise malalignment undetectable by x-ray in supination-external rotation-II (SER-II) injuries.

METHODS

A total of 24 patients with SER-II injuries, as demonstrated by negative gravity stress radiography, were included. Medial clear space (MCS) measurements were performed on bilateral ankle x-rays (injured and contralateral, uninjured side) at several time points as well as bilateral non-weight-bearing CT performed once clinical and radiographic healing was demonstrated (mean = 66 days post injury, range = 61-105 days). Statistical analyses examined differences in measurements between both sides.

RESULTS

Final x-rays demonstrated no differences between normal and injured ankle MCS (P = .441). However, CT coronal/axial MCS measurements were different (P < .05). CT coronal MCS measured wider by a mean difference of 0.67 mm (P < .001).

CONCLUSION

There is a high incidence of subtle mortise malalignment in SER-II ankle fractures, as demonstrated by CT, which is undetectable when assessed by plain radiographs. Although clinical outcomes are yet unknown, there are important implications of the finding of confirmed, subtle mortise malalignment in SER-II injuries and the limitations of x-ray to detect it.

LEVEL OF EVIDENCE

Level III.

Risk Factors for Aseptic Revision of Operatively Treated Ankle Fractures

BACKGROUND

Early revision rates within 12 months after ankle fracture open reduction internal fixation (AF-ORIF) are fairly low; however, they remain relevant given the volume of ankle fractures occurring annually. Understanding these rates is complex because reoperation due to technical or mechanical complications is typically reported alongside soft tissue-related problems such as symptomatic hardware, wound dehiscence, or infection. There are limited data identifying risk factors specifically for revision of ankle fracture fixation in the absence of soft tissue complications. Understanding variables that predispose to aseptic technical and mechanical failure without this confounder may provide insight and improve patient care.

METHODS

A retrospective cohort study was performed at 2 large academic medical centers. Research Patient Data Registry (RPDR) data available from 2002 to 2019 were used to identify patients who underwent aseptic revision of AF-ORIF within 12 months (n = 33). A control group (n = 100) was selected by identifying sequential patients who underwent AF-ORIF not requiring revision within 12 months. Multiple factors were recorded for all patients in both cohorts. Each fracture was also evaluated according to the Ankle Reduction Classification System (ARCS) of Chien et al,⁸ which categorizes biplanar talar displacement in relation to a central tibial plumb line into 1 of 3 grades: A (0-2 mm), B (3-10 mm), and C (>10 mm). Adapted from its original purpose of grading reduction quality, we applied ARCS to pre-reduction radiographs to assess initial fracture displacement. All variables collected were compared in univariate analysis. Variables that achieved significance in univariate comparisons were included as candidates for multivariable analysis.

RESULTS

Final multivariable logistic regression modeling demonstrated the following factors to independently predict the need for aseptic revision surgery: documented falls in the early postoperative period (aOR, 298; 95% CI, 15.4, 5759; P < .001), movement-altering disorders (aOR, 81.7; 95% CI, 4.12, 1620; P = .004), a nonanatomic mortise (medial clear space [MCS] > superior clear space [SCS]) on immediate postoperative imaging (aOR, 38.4; 95% CI, 5.53, 267; P < .001), initial coronal plane tibiotalar displacement >10 mm and sagittal plane tibiotalar dislocation (ARCS-C) (aOR vs ARCS-A, 25.8; 95% CI, 2.81, 237; P = .004), substance abuse (aOR, 15.7; 95% CI, 2.66, 92.8; P = .002), and polytrauma (aOR, 12.3; 95% CI, 2.02, 74.8; P = .006).

CONCLUSION

In this investigation we found a notable increase in risk for revision surgery after AF-ORIF for patients who had one of the following: (1) falls in the early postoperative period, (2) movement-altering disorders, (3) a nonanatomic mortise (MCS > SCS) on immediate postoperative imaging, (4) more severe initial fracture displacement, (5) substance abuse, or (6) polytrauma. Identifying these factors may allow surgeons to better understand risk and counsel patients, and may serve as future targets for intervention aimed at improving patient safety and outcomes after ankle fracture ORIF.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Predictors and Outcomes of Fully Covered Stent Treatment for Anastomotic Esophageal Strictures in Esophageal Atresia

BACKGROUND AND AIMS

Anastomotic strictures following surgical repair is one of the most common complications in esophageal atresia (EA). The utility of esophageal stenting to treat anastomotic esophageal strictures in pediatrics is unclear. Our primary aim was to evaluate whether esophageal stenting, in conjunction with dilation and other endoscopic therapies, prevented surgical stricture resection (SR). Our secondary aims were to evaluate predictors of successful esophageal stenting and evaluate adverse events from stent placement.

METHODS

A retrospective review of pediatric patients with EA complicated by esophageal strictures was performed. The change in stricture diameter in millimeters from the time of stent removal to subsequent endoscopy was defined as delta diameter (ΔD). A receiver operating characteristic (ROC) curve analysis was performed to determine the discriminatory ability of ΔD. Youden J index was used to identify optimal cutoff-point in predicting stent success. A univariate and multivariate analysis were done to assess predictors of success.

RESULT

Forty-nine esophageal anastomoses were stented to treat esophageal strictures. Stents prevented SR in 41% of patients. ROC curve analysis utilizing Youden J index identified ΔD of ≤4 mm (area under the curve = 0.790; 95% confidence interval: 0.655-0.924; P < 0.001) as the optimal cutoff point in differentiating stent success. The most common adverse events were erosions/ulcerations, granulation tissue formation, and vomiting/retching.

CONCLUSION

Stent therapy in preventing SR at the site of EA repair was successful in 41% in our population with good long term follow-up. The most significant predictor of success in this study was the change in luminal diameter (≤4 mm) at initial poststent follow-up.

Initial Esophageal Anastomosis Diameter Predicts Treatment Outcomes in Esophageal Atresia Patients With a High Risk for Stricture Development

Background and Aims: Children with esophageal atresia (EA) who undergo surgical repair are at risk for anastomotic stricture, which may need multiple dilations or surgical resection if the stricture proves refractory to endoscopic therapy. To date, no studies have assessed the predictive value of anastomotic diameter on long-term treatment outcomes. Our aim was to evaluate the relationship between anastomotic diameter in the early postoperative period and need for frequent dilations and stricture resection within 1 year of surgical repair. Methods: A retrospective chart review was performed of patients who had EA repair or stricture resection (SR). Medical records were reviewed to evaluate the diameter of the anastomosis at the first endoscopy after surgery, number and timing of dilations needed to treat the anastomotic stricture, and need for stricture resection. A generalized estimating equations (GEE) modeling with a logit link and binomial family was done to analyze the relationship between initial endoscopic anastomosis diameter and the outcome of needing a stricture resection. Median regression was implemented to estimate the association between number of dilations needed based on initial diameter. Results: A total of 121 patients (56 females) with a history of EA (64% long-gap EA) were identified who either underwent Foker repair at 46% or stricture resection with end-to-end esophageal anastomosis at 54%. The first endoscopy occurred a median of 22 days after surgery. Among all cases, a narrower anastomoses were more likely to need stricture resection with an OR of 12.9 (95% CI, 3.52, 47; p < 0.001) in patients with an initial diameter of <3 mm. The number of dilations that patients underwent also decreased as anastomotic diameter increased. This observation showed a significant difference when comparing all diameter categories when looking at all surgeries taken as a whole (p < 0.008). Conclusion: Initial anastomotic diameter as assessed via endoscopy performed after high-risk EA repair predicts which patients will require more esophageal dilations as well as the likelihood for stricture resection. This data may serve to stratify patients into different endoscopic treatment plans.

Ascending Aortoplasty in Pediatric Patients Undergoing Aortic Valve Procedures

BACKGROUND

The risks of ascending aortic dilation and indications for intervention in pediatric patients are unclear. Given the concern for aortic size mismatch with growth, larger ascending aortic diameters have been accepted in pediatric patients. The purpose of this study was to evaluate the effectiveness of ascending aortic reduction at the time of aortic valve surgery and its effect on recurrent aortic regurgitation.

METHODS

A retrospective 8-year observational review (2010-2018) was conducted in pediatric patients with dilated ascending aorta undergoing aortic valve surgery at a single institution.

RESULTS

Forty-seven patients underwent ascending aortoplasty during aortic valve surgery, of which 39 patients with complete data points had preoperative mean ascending aortic Z-scores of 5.35 ± 1.52 reduced to 1.22 ± 1.63 (P < .001) postoperatively. Ascending aortic Z-scores remained similar at 1.37 ± 1.72 at latest follow-up (P = .306). In contrast our matched control group (n = 39) without ascending aortoplasty had preoperative mean ascending aortic Z-scores of 4.15 ± 1.65 reduced to 3.26 ± 2.0 at the midterm follow-up. This reduction was significantly larger in the aortoplasty group, with an average difference in these changes of 3.12 (95% confidence interval, 2.43-3.8; P < .001). Multivariable logistic regression (controlling for aortic valve intervention type and body surface area) showed a 6.84 odds of moderate to severe aortic regurgitation at follow-up in the control group compared with the aortoplasty group (95% confidence interval, 1.43-32.8; P = .016). There were no complications associated with ascending aortoplasty.

CONCLUSIONS

Ascending aortoplasty is effective in reducing ascending aortic dimensions and recurrent aortic regurgitation in pediatric patients. Longer-term follow-up is necessary to determine continued rate of growth.

Legacy health effects among never smokers exposed to occupational secondhand smoke

OBJECTIVES

Secondhand tobacco smoke (SHTS) is a tremendous public health hazard, leading to morbidity and premature mortality worldwide, with racial and ethnic minorities and those of lower socioeconomic status disproportionately affected. Flight attendants were historically exposed to high levels of SHTS in the aircraft cabin. The health effects of active smoking are known to persist for up to a lifetime, but the legacy effects of SHTS exposure have not been well characterized.

DESIGN

We aimed to evaluate the legacy health effects of occupational SHTS exposure among never smoking workers using the resources of the Harvard Flight Attendant Health Study, a large study of cabin crew health. We evaluated associations between SHTS exposure and a range of diagnoses using multivariate logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs), employing a case-control sampling method and applying the bootstrap method to increase accuracy and precision of results.

RESULTS

We found no evidence of positive associations between SHTS and any cancer, but observed associations between SHTS and cardiac outcomes, including myocardial infarction (OR = 140, 95% CI: 1·04, 3·27) and peripheral artery disease (OR = 1·27, 95% CI: 1·00, 1·97). We also found associations between SHTS exposure and repeated pneumonia (OR = 1·06, 95% CI: 1·02, 1·10).

CONCLUSIONS

Our study reports associations between legacy SHTS exposure going back decades and severe cardiac and respiratory health outcomes. Given the high prevalence of ongoing and historical SHTS exposure, our findings, if confirmed, have important implications for smoking cessation efforts, health education, and clinical guidelines.

Cancer prevalence among flight attendants compared to the general population

BACKGROUND

Flight attendants are an understudied occupational group, despite undergoing a wide range of adverse job-related exposures, including to known carcinogens. In our study, we aimed to characterize the prevalence of cancer diagnoses among U.S. cabin crew relative to the general population.

METHODS

In 2014-2015, we surveyed participants of the Harvard Flight Attendant Health Study. We compared the prevalence of their self-reported cancer diagnoses to a contemporaneous cohort in the National Health and Nutrition Examination Survey (NHANES 2013-2014) using age-weighted standardized prevalence ratios (SPRs). We also analyzed associations between job tenure and the prevalence of selected cancers, using logistic regression and adjusting for potential confounders.

RESULTS

Compared to NHANES participants with a similar socioeconomic status (n = 2729), flight attendants (n = 5366) had a higher prevalence of every cancer we examined, especially breast cancer, melanoma, and non-melanoma skin cancer among females. SPR for these conditions were 1.51 (95% CI: 1.02, 2.24), 2.27 (95% CI: 1.27, 4.06), and 4.09 (95% CI: 2.70, 6.20), respectively. Job tenure was positively related to non-melanoma skin cancer among females, with borderline associations for melanoma and non-melanoma skin cancers among males. Consistent with previous studies, we observed associations between job tenure and breast cancer among women who had three or more children.

CONCLUSIONS

We observed higher rates of specific cancers in flight attendants compared the general population, some of which were related to job tenure. Our results should be interpreted in light of self-reported health information and a cross-sectional study design. Future longitudinal studies should evaluate associations between specific exposures and cancers among cabin crew.