COVID-19-induced Esophageal Necrosis Requiring Emergent Total Esophagectomy in a Vaccinated Patient.

Acute esophageal necrosis may be a potential complication of Coronavirus Disease 2019 (COVID-19). COVID-19 has been associated with a variety of sequelae, including acute respiratory distress syndrome, myocarditis, and thromboembolic events. Here, we present a case of a 43-year-old male who was admitted for acute necrotizing pancreatitis and found to have COVID-19 pneumonia. He subsequently developed acute esophageal necrosis requiring a total esophagectomy. Currently, there are at least five other reported cases of esophageal necrosis with concomitant COVID-19 infection. This case is the first requiring esophagectomy. Future studies may establish esophageal necrosis as a known complication of COVID-19.

Examining Implicit Bias Differences in Pediatric Surgical Fellowship Letters of Recommendation Using Natural Language Processing.

OBJECTIVE: We analyzed the prevalence and type of bias in letters of recommendation (LOR) for pediatric surgical fellowship applications from 2016-2021 using natural language processing (NLP) at a quaternary care academic hospital. DESIGN: Demographics were extracted from submitted applications. The Valence Aware Dictionary for sEntiment Reasoning (VADER) model was used to calculate polarity scores. The National Research Council dataset was used for emotion and intensity analysis.  The Kruskal-Wallis H-test was used to determine statistical significance.  SETTING: This study took place at a single, academic, free standing quaternary care children's hospital with an ACGME accredited pediatric surgery fellowship. PARTICIPANTS: Applicants to a single pediatric surgery fellowship were selected for this study from 2016 to 2021. A total of 182 individual applicants were included and 701 letters of recommendation were analyzed. RESULTS: Black applicants had the highest mean polarity (most positive), while Hispanic applicants had the lowest.  Overall differences between polarity distributions were not statistically significant.   The intensity of emotions showed that differences in "anger" were statistically significant (p=0.03).  Mean polarity was higher for applicants that successfully matched in pediatric surgery. DISCUSSION: This study identified differences in LORs based on racial and gender demographics submitted as part of pediatric surgical fellowship applications to a single training program. The presence of bias in letters of recommendation can lead to inequities in demographics to a given program. While difficult to detect for humans, natural language processing is able to detect bias as well as differences in polarity and emotional intensity. While the types of emotions identified in this study are highly similar among race and gender groups, the intensity of these emotions revealed differences, with "anger" being most significant. CONCLUSION: From this work, it can be concluded that bias in LORs, as reflected as differences in polarity, which is likely a result of the intensity of the emotions being used and not the types of emotions being expressed.   Natural language processing shows promise in identification of subtle areas of bias that may influence an individual's likelihood of successful matching.

Association Between the Modified Frailty Index and Outcomes Following Lobectomy.

INTRODUCTION: Elective thoracic surgery is safe in well-selected elderly patients. The association of frailty with postoperative morbidity in elective-lobectomy patients is understudied. We examined frailty as defined by abbreviated modified frailty index (mFI-5), mFI-11 in the thoracic surgery population, and the correlation between frailty and postoperative complications. METHODS: We studied outcomes of patients in two cohorts, 2010-2012 and 2013-2019, from the National Surgical Quality Improvement Program (NSQIP) database and used multivariable logistic regression models to predict all postoperative morbidity, mortality, and major morbidity. The mFI-5 could be calculated for all subjects (both 2010-2012, and 2013-2019); the mFI-11 could only be calculated for the 2010-2012 cohort. Patient frailty was defined as mFI≥3 (with either index). We used odds ratios (ORs) to examine associations of preoperative characteristics with postoperative complications and C-statistics to assess overall predictive power. RESULTS: Complications were less prevalent in the 2013-2019 cohort (17.9% versus 19.5%, P = 0.008). Open lobectomies were more common in the 2010-2012 cohort (53.9% versus 34.6%) and were strongly associated with postoperative morbidity and mortality (ORs >1.5) in both cohorts. Each frailty measure was associated with morbidity and mortality (ORs >1.4) after adjusting for other significant preoperative factors. Models on the 2010-2012 cohort had nearly identical C-statistics using the mFI-11 versus mFI-5 frailty indices (0.6142 versus 0.6139; P > 0.8). CONCLUSIONS: Frailty, as captured in the mFI-5, is a significant associated factor of postoperative morbidity and mortality following elective lobectomies. As a modifiable risk factor, frailty should be considered in surgical decision-making and when counseling patients regarding perioperative risks.

Thymectomy for treatment of anti-NMDA receptor encephalitis.

In this case report, we present a 25-year-old woman who was diagnosed with anti-N-methyl-D-aspartate (NMDA) receptor encephalitis and subsequently was found to have thymic hyperplasia. She underwent robotic bilateral access thymectomy for treatment of her anti-NMDA receptor encephalitis and has remained asymptomatic after her operation without any medication. This is only the second reported case of thymectomy for treatment of this condition. This case may further suggest thymic tissue is involved in the development of anti-NMDA receptor encephalitis and that thymectomy is an appropriate treatment for a subset of patients with this disease.

Use of In-Situ Simulation Based Clinical Systems Test of Thoracic Robotic Surgery Emergencies.

INTRODUCTION: With the advancement of robotic surgery, some thoracic surgeons have been slow to adopt to this new operative approach, in part because they are un-scrubbed and away from the patient while operating. Aiming to allay surgeon concerns of intra-operative emergencies, an insitu simulation-based clinical system's test (SbCST) can be completed to test the current clinical system, and to practice low-frequency, high-stakes clinical scenarios with the entire operating room (OR) team. METHODS: Six different OR teams completed an insitu SbCST of an intra-operative pulmonary artery injury during a robot-assisted thoracic surgery at a single tertiary care center. The OR team consisted of an attending thoracic surgeon, surgery resident, anesthesia attending, anesthesia resident, circulating nurse, and a scrub technician. This test was conducted with an entire OR team along with study observers and simulation center staff. Outcomes included the identified latent safety threats (LSTs) and possible solutions for each LST, culminating in a complete failure mode and effects analysis (FMEA). A Risk Priority Number (RPN) was determined for each LST identified. Pre- and post-simulation surveys using Likert scales were also collected. RESULTS: The six FMEAs identified 28 potential LSTs in four categories. Of these 28 LSTs, nine were considered high priority based on their Risk Priority Number (RPN) with seven of the nine being repeated multiple times. Pre- and post-simulation survey responses were similar, with the majority of participants (94%) agreeing that high fidelity simulation of intra-operative emergencies is helpful and provides an opportunity to train for high-stakes, low-frequency events. After completing the SbCST, more participants felt confident that they knew their role during an intra-operative emergency than their pre-simulation survey responses. All participants agreed that simulation is an important part of continuing education and is helpful for learning skills that are infrequently used. Following the SbCST, more participants agreed that they knew how to safely undock the da Vinci robot during an emergency. CONCLUSIONS: SbCSTs provide an opportunity to test the current clinical system with a low-frequency, high-stakes event and allow medical personnels to practice their skills and teamwork. By completing multiple SbCSTs, we were able to identify multiple LSTs within different OR teams, allowing for a broader review of the current clinical systems in place. The use of these SbCSTs in conjunction with debriefing sessions and FMEA completion allows for the most significant potential improvement of the current system. This study shows that SbCST with FMEA completion can be used to test current systems and create better systems for patient safety.

Resolution of Severe Graft Steatosis Before Living-Donor Liver Transplant After 86 Pounds of Weight Loss.

Living-donor liver transplant allows for expedited transplant, with outcomes shown to be superior compared with deceased-donor liver transplant due to earlier intervention, with reduced hospital costs. However, they only comprise about 5% of liver transplants nationally. This is due to a limited pool of willing donors and donor exclusions for medical and psycho-social reasons. The leading reason for why potential living liver donors are not eligible is nonalcoholic fatty liver disease. Donor hepatic steatosis limits the number of potential living-donor liver transplants because it is associated with perioperative complications in both donors and recipients. Here, we describe a 37-year-old male potential living donor who presented with hepatic steatosis based on preoperative imaging. Over a 1-year period, he was able to completely reverse his hepatic steatosis by losing about 86 pounds (from 279 to 193 pounds), reducing his body mass index from 40 to 28.55 kg/m². Computed tomography and biopsy results after his weight loss showed that he had no hepatic steatosis, allowing him to become a living donor for his mother. Postoperative periods for both the donor and recipient were uncomplicated. This case suggests that the pool of living liver donors could be expanded through dietary and behavior modifications, thus increasing the number of potential living donors and providing potential recipients with more transplant options. Enlarging this pool of donors will also improve transplant outcomes for donors and recipients and lower overall health care costs compared with deceased-donor liver transplant.

Assessing screening, brief intervention, and referral to treatment (SBIRT) compliance and disparities for pediatric inpatients at a tertiary care facility.

BACKGROUND: Pediatric trauma centers are required to screen patients for alcohol or other drug use (AOD), Briefly Intervene, and Refer these patients to Treatment (SBIRT) to meet Level 1 and 2 trauma center requirements set by the American College of Surgeons. We evaluated if a mandatory electronic medical record tool increased SBIRT screening compliance for all trauma and non-trauma adolescent inpatients. METHODS: A SBIRT electronic medical record tool was implemented for pediatric inpatient AOD screening. A positive screen prompted brief intervention and referral for treatment in coordination with social work and psychiatric consultants. We compared pre and post- implementation screening rates among inpatients age 12-18 years and performed sub-group analyses. RESULTS: There were 873 patients before and 1,091 after implementation. Questionnaire screening increased from 0% to 34.4% (p < 0.001), without an increase in positivity rate, and lab screening decreased by 4.2% (p = 0.003). Females were more likely to receive a social work consultation than males (14.5 vs 7.5%, p < 0.001), despite a greater number of positive questionnaires among males (9.5 vs 17.9%, p = 0.013). White patients were more likely to receive a social work consultation (12.9%) compared to Asian (2%), Black (6.3%), and Other (6.9%) (p = 0.007), despite comparable rates of positive screenings. When comparing English to non-English speakers, English speakers were more likely to have a social work consult (12.0% vs 2.4%, p < 0.001) and psychiatry/psychology consult (13.6 vs 5.6%, p = 0.011). CONCLUSION: Multidisciplinary training along with an electronic medical record tool increased SBIRT protocol compliance. Demographic disparities in intervention rates may exist.

Paraconduit Hiatal Hernia Following Esophagectomy: Incidence, Risk Factors, Outcomes and Repair.

BACKGROUND: Paraconduit hiatal hernia (PCHH) is a known complication of esophagectomy with significant morbidity. PCHH may be more common with the transition to a minimally invasive approach and improved survival. We studied the PCHH occurrence following minimally invasive esophagectomy to determine the incidence, treatment, and associated risk factors. METHODS: We retrospectively reviewed records of patients who underwent esophagectomy at an academic tertiary care center between 2013-2020. We divided the cohort into those who did and did not develop PCHH, identifying differences in demographics, perioperative characteristics and outcomes. We present video of our laparoscopic repair with mesh. RESULTS: Of 49 patients who underwent esophagectomy, seven (14%) developed PCHH at a median of 186 d (60-350 d) postoperatively. They were younger (57 versus 64 y, P< 0.01), and in cases of resection for cancer, more likely to develop tumor recurrence (71% versus 23%, P= 0.02). There was a significant difference in 2-y cancer free survival of patients with a PCHH (PCHH 19% versus no hernia 73%, P< 0.01), but no significant difference in 5-y overall survival (PCHH 36% versus no hernia 68%, P= 0.18). Five of seven PCHH were symptomatic and addressed surgically. Four PCHH repairs recurred at a median of 409 d. CONCLUSIONS: PCHH is associated with younger age and tumor recurrence, but not mortality. Safe repair of PCHH can be performed laparoscopically with or without mesh. Further studies, including systematic video review, are needed to address modifiable risk factors and identify optimal techniques for durable repair of post-esophagectomy PCHH.

Patterns of General Surgery Residency Social Media Use in the Age of COVID-19.

OBJECTIVE: The role for social media use by General Surgery departments continues to expand and social media accounts have been increasingly implemented as a tool for residency program for promotion and engagement. The importance of these accounts appears to have increased given the unprecedented changes with COVID-19 and the dramatic and unpredictable change to the application cycle including the use of virtual interviews, suggesting a perceived need for increased online engagement with applicants. The purpose of this study was to determine the patterns of creation and usage of Twitter and Instagram accounts of Accreditation Council for Graduate Medical Education (ACGME)-accredited General Surgery residency programs and their associated surgical departments. METHORDS: A cross-sectional study of the use of Twitter and Instagram by the 332 ACGME-accredited General Surgery residency programs and their associated departments was conducted in February 2021. Twitter and Instagram accounts were identified by accessing program/department websites as well as social media platform and internet searches. Year of creation, number of followers, and number of posts (July 1, 2018-December 31, 2020) were collected. Trends in usage were compared across years stratified by platform and by account owner (department vs. residency). RESULTS: Instagram accounts are more than five-times greater for residencies compared to departments (42% vs 8%, p < 0.001). There was not a significant difference between the number of department and residency Twitter accounts (26% vs 23%, p = 0.37). Significantly more residency Instagram and Twitter accounts were created or first posted in 2020 compared to department accounts (Instagram: 100 vs 7, p < 0.001; Twitter: 31 vs 6, p = 0.001). Over 18% of residency programs had both Twitter and Instagram accounts compared to only 6% of departments (p < 0.001). However, department Twitter and Instagram accounts had significantly higher median total posts from 7/1/2018-12/31/2020 (Twitter: p = 0.0001, Instagram p = 0.004). While the number of Instagram followers and accounts being followed were similar between residencies and departments, department Twitter accounts had a larger median number of followers (1141 vs. 430, p=0.003) and account followings (308 vs. 192, p = 0.001) compared to residency accounts. CONCLUSIONS: The number of residency social media accounts has significantly increased in 2020 compared to account creation of departments, with Instagram account creation exceeding that of Twitter and of departments. The opposite pattern in usage was seen related to number of posts, and with Twitter, followers, and number of followings, with departments outpacing residencies. This significant increase in account creation may have been influenced by the COVID-19 pandemic and the change to a virtual interview season, suggesting an unprecedented need for online engagement with applicants. As the increased social media presence will likely persist in future application cycles, further study about the impact of residency social media use on recruitment and applicant decision-making as well as effective strategies, is needed.

Does speed matter? A look at NSQIP-P outcomes based on operative time.

BACKGROUND: Appendicitis is a common pediatric surgical condition, comprising a large burden of healthcare costs. We aimed to determine if prolonged operative times were associated with increased 30-day complication rates when adjusting for pre-operative risk factors. METHODS: Patients <18 years old, diagnosed intraoperatively with acute uncomplicated appendicitis and undergoing laparoscopic appendectomy were identified from the NSQIP-P 2012-2018 databases. The primary outcome, "infectious post-operative complications", is a composite of sepsis, deep incisional surgical site infections, wound disruptions, superficial, and organ space infections within 30-days of the operation. Secondary outcomes included return to the operating room and unplanned readmissions within 30 days. Logistic regression models were used to assess associations between operative time and each outcome. A Receiver Operating Characteristic (ROC) curve was generated from the predicted probabilities of the multivariate model for infectious post-operative complications to examine operative times. RESULTS: Between 2012 and 2018, 27,763 pediatric patients with acute uncomplicated appendicitis underwent a laparoscopic appendectomy. Over half the population was male (61%) with a median operative time of 39 min (IQR 29-52 min). Infectious post-operative complication rate was 2.8% overall and was highest (8%) among patients with operative time ≥ 90 min (Fig. 1). Unplanned readmission occurred in 2.9% of patients, with 0.7% returning to the operating room. Each 30-min increase in operating time was associated with a 24% increase in odds of an infectious post-operative complication (OR=1.24, 95% CI=1.17-1.31) in adjusted models. Operative time thresholds predicted with ROC analysis were most meaningful in younger patients with higher ASA class and pre-operative SIRS/Sepsis/Septic shock. Longer operative times were also associated with higher odds of unplanned readmission (OR=1.11, 95% CI=1.05-1.18) and return to the operating room (OR=1.13, 95% CI=1.02-1.24) in adjusted models. CONCLUSION: There is a risk-adjusted association between prolonged operative time and the occurrence of infectious post-operative complications. Infectious postoperative complications increase healthcare spending and are currently an area of focus in healthcare value models. Future studies should focus on addressing laparoscopic appendectomy operative times longer than 60 min, with steps such as continuation of antibiotics, shifting roles between attending and resident surgeons, and simulation training. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Letters of recommendation for pediatric surgery fellowship: Analysis of linguistic differences based on gender of the applicant.

BACKGROUND: Gender bias in letters of recommendation (LOR) has been reported for candidate selection in academic medicine, typically with females frequently described with communal terms (e.g. helpful, kind, interpersonal) and males described more with agentic terms (e.g. assertive, intellectual, ambitious). This study examined the presence of linguistic gender differences in LOR for Pediatric Surgery Fellowship. METHODS: LOR submitted to a single pediatric surgery fellowship program between 2014 and 2018 were retrospectively reviewed and analyzed using a previously validated Linguistic Inquiry and Word Count Software (LIWC) program. Descriptive statistics and bivariate analysis were employed in our analysis. Multivariable logistic regression models were built to assess independent association of LIWC variables with applicant gender, LOR writer gender, and applicant-writer gender concordance. RESULTS: 1264 LOR from 325 applicants (51% female) were analyzed. Of the letter writers, 83% were male, 57% were professors, and 7.6% were Pediatric Surgery Fellowship Program Directors. The overall median average word count was 518 words, with no significant difference in LOR word count between applicant genders. Compared to male applicants, female applicants were described significantly more with work words (e.g. excellent, work; p = 0.04). Male LOR writers used authentic words (e.g. honest, humble; p = 0.006) and home words (e.g. family, house; p = 0.04) significantly more than female LOR writers. There were no significant differences in the use of agentic and communal words between genders. CONCLUSION: While there are linguistic differences in LOR for candidates in the Pediatric Surgery match based on gender, previously described overt gender bias was not seen in this study. Interestingly, female candidates were described more with work words, like excellent; a reversal of previously described gender bias in academic medicine. These findings may be due to the unique interpersonal and multidisciplinary skills required in pediatric surgery and may represent a unique form of gender bias that warrants further study.

Outcomes of Pediatric Central Venous Access Device Placement With Concomitant Surgical Procedures.

BACKGROUND: Children frequently undergo placement of a tunneled central venous catheter or port (CVAD) concomitantly with other surgical procedures (CVAD-CP), but the risk factors for early CVAD complications with this practice are unclear. METHODS: Children undergoing CVAD-CP were identified from the National Surgical Quality Improvement Program-Pediatric 2012-2016 database. Predictor variables included demographics, CP characteristics, malignancy, and CVAD type. Outcome variables were CVAD-associated bloodstream infection (CLABSI) or new deep venous thrombosis (nDVT) within 30 d. Patients with and without CLABSI or nDVT were compared, and the temporal relationship of nDVT and CLABSI was investigated. Multivariable logistic regression modeling was used to assess independent risk factors for CLABSI. RESULTS: Of 2036 patients included, median age was 1.5 y, 35% had malignancy, and 40% had a clean concomitant procedure. Overall, 1.3% developed CLABSI and 0.7% developed nDVT. Multivariable regression modeling revealed higher risk of CLABSI with clean CPs (odds ratio [OR] 2.4, 95% confidence interval [CI] 1.06-5.34, P = 0.035), tunneled catheters (OR 3.2, 95% CI 1.18-8.56, P = 0.022), and longer anesthesia duration (OR 1.02 per 10 min, 95% CI 1.00-1.04, P = 0.042). nDVT was strongly associated with CLABSI (21% CLABSI among those with DVT, 0.5% among those without, P ≤ 0.0001). In all cases of nDVT with CLABSI, the diagnosis of DVT preceded diagnosis of CLABSI, by a median of 7 d. CONCLUSIONS: The type of CVAD and characteristics of the concomitant procedure influence early CLABSI after CVAD-CP. The unexpected finding of higher CLABSI rates among clean concomitant procedures suggests that perioperative prophylactic antibiotics should not be withheld in this setting, but requires prospective validation. nDVT is frequently diagnosed prior to CLABSI, suggesting a possible role for antibiotics in the treatment of postoperative DVT after CVAD placement.

Risk factors for complications after abdominal surgery in children with sickle cell disease.

BACKGROUND: Abdominal surgery in children with sickle cell disease (SCD) carries an increased risk of postoperative complications. Preoperative transfusions are frequently given to decrease the risk of vasoocclusive events. However, risk factors for postoperative complications are not well-defined in the pediatric population. METHODS: Pediatric patients with SCD undergoing common abdominal operations were identified from the National Surgical Quality Improvement Program-Pediatric (NSQIP-P) database from 2012 to 2018. Outcomes of interest were the incidence rates of 1) any complication or readmission, and 2) serious SCD-related complications (stroke, new onset seizure, ventilator support >24 h postoperatively, or readmission with SCD crisis within 30 days of surgery). Patients were categorized by transfusion approach (transfusion within 48 h before surgery vs. no transfusion) and preoperative hematocrit (<21.0, 21.0-23.9, 24.0-26.9, 27.0-29.9, ≥30.0). Stratified bivariate analyses and multivariable logistic regression were used to identify independent risk factors for complications. RESULTS: A total of 813 patients met inclusion criteria. There were 470 cholecystectomy, 251 splenectomy, 39 appendectomy, and 53 combination procedures; 13% of cases were urgent or emergent. Preoperative hematocrit levels were <21.0 in 3%, 21.0-23.9 in 10%, 24.0-26.9 in 17%, 27.0-29.9in 30%, and ≥30.0 in 41% of patients; 52% received perioperative transfusion. The 30-day incidences of any complication/readmission and SCD-related complications were 12% and 4%, respectively. On bivariate analyses, urgent/emergent case status was the only significant predictor of complications, carrying risk of 20% and 8% for overall and SCD-related complications, respectively; this finding persisted on multivariable logistic regression (OR 1.83, 95% CI 1.0.2-3.29, p = 0.04). Neither preoperative transfusion nor preoperative hematocrit level was associated with complication risk, although there was a trend toward higher SCD-related complications in patients with preoperative hematocrit <21.0 (p = 0.07). CONCLUSION: In this large cohort of pediatric SCD patients undergoing abdominal surgery, there was no clear association between postoperative complications and the transfusion approach or the preoperative hematocrit level within the range above 21.0. Urgent/emergent surgical procedures carried a nearly two-fold higher complication risk compared to elective procedures. Future studies should prospectively evaluate preoperative transfusion approaches and compare immediate and delayed operative management to nonoperative management in this population. LEVEL OF EVIDENCE: III Retrospective review.

30-Day Outcomes Following Esophageal Replacement in Children: A National Surgical Quality Improvement Project Pediatric Analysis.

INTRODUCTION: The optimal method of esophageal replacement remains controversial. The aim of this study was to evaluate 30-d outcomes of children in the National Surgical Quality Improvement Project Pediatric (NSQIP-P) database who underwent esophageal replacement from 2012 to 2018. METHODS: Demographics, comorbidities, and procedural technique was identified in NSQIP-P and reviewed. Thirty-day outcomes were assessed and stratified by gastric pull-up or tube interposition versus small bowel or colonic interposition. Categorical and continuous variables were assessed by Pearson's chi-square, Fisher's exact, and Wilcoxon rank-sum tests, respectively. Multivariate logistic regression was performed to estimate the effects of procedure technique and clinical risk factors on patient outcomes. RESULTS: Of the 99 cases of esophageal replacement included, 52 (52.5%) utilized a gastric conduit, whereas 47 (47.5%) involved small bowel/colonic esophageal interposition. Overall risk of complications was 52.5%, the most common of which were perioperative transfusion (30.3%), surgical site infection (11.1%), and sepsis (9.1%). Risk of unplanned reoperation was 17.2%, and risk of mortality was 3.0%. Risk for complications, reoperation, and readmission did not differ significantly between those who underwent gastric esophageal replacement and those who underwent small bowel or colonic interposition. Median operative time was shorter in the gastric esophageal replacement group (5.2 versus 8.1 h, P = 0.009). CONCLUSIONS: Among children in NSQIP-P who underwent esophageal replacement from 2012 to 2018, the risk of 30-d complications, unplanned reoperation, and mortality was relatively frequent and was similar across operative techniques. Opportunities exist to improve preoperative optimization, utilization of blood transfusion services, and infectious complications in the perioperative period irrespective of operative technique. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

External caliper-based measurements of the modified percent depth as an alternative to cross-sectional imaging for assessing the severity of pectus excavatum.

BACKGROUND: Cross-sectional imaging (CSI) may be clinically unnecessary in the evaluation of pectus excavatum (PE). The purpose of our study was to prospectively evaluate the accuracy and reliability of the modified percent depth (MPD), derived from caliper-based external measurements, in identifying PE. METHODS: Children 11-21 years old presenting for evaluation of PE or to obtain thoracic cross-sectional imaging for other indications were measured to derive the Modified Percent Depth. The Haller Index (HI) and Correction Index (CI) were calculated from CSI. Receiver-Operator Characteristic (ROC) analysis was used to compare the sensitivity and specificity of MPD, HI, and CI. Interrater reliability was assessed using Spearman's correlation coefficient and Cohen's Kappa coefficient. RESULTS: Of 199 patients, 76 (38%) had severe PE. Median age was 16 years (range = 11-21). The median Modified Percent Depth was 21.4% (IQR = 16.2-26.3) among those with PE versus 4.1% (IQR = 1.7-6.4) in those without (p < 0.001). MPD ≥ 11% exhibited similar sensitivity and specificity to HI ≥ 3.25 and CI ≥ 10 for identifying PE (ROC 0.98 vs. 0.97 vs. 0.98, respectively, p = 0.41). With respect to interrater reliability, independent clinicians' caliper measurements exhibited 87% agreement when identifying MPD ≥ 11% (p < 0.001) with excellent correlation (Spearman's ρ > 0.71, p < 0.001). CONCLUSION: Caliper-based, physical examination measurements of the Modified Percent Depth reliably identify pectus excavatum and represent an alternative to CSI-based measurements for the assessment of PE. TYPE OF STUDY: Diagnostic test. LEVEL OF EVIDENCE: Level II.