Photoacoustic imaging for non-invasive assessment of biomarkers of intestinal injury in experimental necrotizing enterocolitis.

BACKGROUND: Necrotizing enterocolitis (NEC) is an often-lethal disease of the premature infant intestinal tract, exacerbated by significant diagnostic difficulties. In NEC, the intestine exhibits hypoperfusion and dysmotility, contributing to disease pathogenesis. However, these features cannot be accurately and quantitively assessed with current imaging modalities. We have previously demonstrated the ability of photoacoustic imaging (PAI) to non-invasively assess intestinal tissue oxygenation and motility in a healthy neonatal rat model. METHODS: In this first-in-disease application, we evaluated NEC using PAI to assess intestinal health biomarkers in an experimental model of NEC. NEC was induced in neonatal rats from birth to 4-days. Healthy breastfed (BF) and NEC rat pups were imaged at 2- and 4-days. RESULTS: Intestinal tissue oxygen saturation was measured with PAI, and NEC pups showed significant decreases at 2- and 4-days. Ultrasound and PAI cine recordings were used to capture intestinal peristalsis and contrast agent transit within the intestine. Intestinal motility, assessed using computational intestinal deformation analysis, demonstrated significant reductions in both early and established NEC. NEC damage was confirmed with histology and dysmotility was confirmed by small intestinal transit assay. CONCLUSION: This preclinical study presents PAI as an emerging diagnostic imaging modality for intestinal disease assessment in premature infants. IMPACT: Necrotizing enterocolitis (NEC) is a devastating intestinal disease affecting premature infants with significant mortality. NEC presents significant clinical diagnostic difficulties, with limited diagnostic confidence complicating timely and effective interventional efforts. This study is an important foundational first-in-disease preclinical study that establishes the utility for PAI to detect changes in intestinal tissue oxygenation and intestinal motility with NEC disease induction and progression. This study demonstrates the feasibility and exceptional promise for the use of PAI to non-invasively assess oxygenation and motility in the healthy and diseased infant intestine.

Neonatal complicated intraabdominal infection.

PURPOSE OF REVIEW: The purpose of this review is to summarize the treatment of complicated intraabdominal infections (cIAIs) in premature infants. RECENT FINDINGS: Recent work has continued to define the complex nature of cIAIs and necrotizing enterocolitis (NEC). This includes new findings on the microbiome, breast milk and risk factors associated with NEC. The treatment of cIAIs employs a combination of both surgical and medical treatment. Further look at what type and timing of surgical intervention is used as well as the ideal antibiotic regimen. Upcoming research is highlighted in future directions of NEC treatment. SUMMARY: cIAIs in premature infants is a challenging disease with more research needed to further delineate the pathophysiology and treatment options.

Myxoid liposarcoma: local relapse and metastatic pattern in 43 patients.

BACKGROUND: Liposarcomas are the second most common type of soft tissue sarcomas, 30-50% of these are of myxoid subtype. The aim of this retrospective study was to analyze the local control rate, the metastatic pattern and survival of patients in a consecutive single-institution series. METHODS: From 1983 to 2015, 43 patients with myxoid liposarcoma of the extremities and trunk wall underwent resections. The margin was defined as R0 (wide) or R1 (marginal). Patients were followed for evidence of local recurrence or distant metastasis. Overall and recurrence-free survival was calculated. RESULTS: The mean age was 48.6 years. The lower extremity was involved in 40 cases, the mean tumour size was 12 cm. In 31 cases a wide and in 12 cases a marginal resection was performed. Grading was G1 in 14, G2 in 25 and G3 in 4 cases. Nine patient died in follow-up, 4 of them with metastatic disease, all nonpulmonary. 5-year local recurrence (LR) free survival was 82%. 4 (9.3%) patients developed LR (all R1). Overall survival (OS) was 81% after 5 and 72% after 10 years. In multivariate analysis age and Grading proved to be significant on OS. According to univariate analysis, only age over 48 years and distant metastasis had a significant impact on overall survival. CONCLUSIONS: Patients with myxoid liposarcomas have a good prognosis. Myxoid liposarcoma has a distinct pattern of nonpulmonary metastatic disease. Therefore, patients with high-risk extremity myxoid liposarcoma should undergo imaging studies of the chest, abdomen, spine and pelvis as part of their staging and follow-up examinations preferably with whole body MRI, or CT scans and MRI of the spine and pelvic region for detection of suspected metastatic disease.

The role of surgical margins in atypical Lipomatous Tumours of the extremities.

BACKGROUND: Atypical lipomatous tumours (ALT) are common adipocytic tumours. Due to their large size and deep-seated location, wide resection might result in severe functional deficits. The question which margins should be aimed is hence discussed controversially. METHODS: Forty consecutive patients underwent limb-sparing resections. Margins were defined as R0 (wide resection), R1 (marginal resection) or R2 if tumour was left. All patients were followed for evidence of local recurrence or remote metastases. Overall and recurrence-free survival was calculated. RESULTS: The mean age at the time of surgery was 61.9 years. The mean tumour diameter was 17 cm with no patient having metastatic disease. In 8 cases a wide (R0) resection, in 31 cases a marginal (R1) and in one patient a R2-resection was performed. The median follow-up time was 40 months. Four patients died due to causes that were not tumour-related. 3 (7.5%) patients (all R1) developed local recurrences. Two of our 3 recurrences in this series occurred in 6 already recurring cases. We observed no dedifferentiation of tumours and no metastatic disease. CONCLUSIONS: ALT represents a comparatively common diagnosis in large deep-seated lesions of the extremities, especially in patients over 60 years. Marginal resection shows an acceptable rate of local recurrence. The risk of dedifferentiation as proven also in a metaanalysis of the English literature of the last 30 years is close to 1%, metastatic disease is exceedingly rare.

The Effect of 4-Factor Prothrombin Complex Concentrate to Reverse Factor Xa Inhibitors in Patients With Traumatic Intracranial Hemorrhage.

The utility of 4-factor prothrombin complex concentrate (4F-PCC) for reversal in patients on factor Xa inhibitors (XaI) is unclear, specifically in mild traumatic brain injury (mTBI). This is a retrospective review over 6 years at a level 1 trauma center of patients presenting with mTBI on XaI comparing outcomes for those that received 4F-PCC to those that did not. 140 patients were included, 103 (74%) of these patients received 4F-PCC while 37 (26%) did not. There was no significant difference in neurologic decline within 48 hours of admission or need for neurosurgical intervention. Interestingly, there was no difference in ICH progression (16% vs 14%, P = .77). In this study, 4F-PCC given after mild traumatic brain injury did not impact ICH progression, neurologic decline, or need for neurosurgical intervention. Although limited in numbers, this study suggests that 4F-PCC is not necessarily required in mTBI and further studies are indicated.

Contemporary management and outcomes of blunt traumatic American Association for the Surgery of Trauma Organ Injury Scale grades III and IV pancreatic injuries in children: A Trauma Quality Improvement Program analysis.

BACKGROUND: The Trauma Quality Improvement Program (TQIP) database has delineated management strategies and outcomes for adults with American Association for the Surgery of Trauma Organ Injury Scale grades III and IV pancreatic injuries and suggests that nonoperative management (NOM) is a viable option for these injuries. However, management strategies vary for children following significant pancreatic injuries and outcomes for these intermediate/high-grade injuries have not been sufficiently studied. Our aim was to describe the management and outcomes for grades III and IV pancreatic injuries using TQIP. We hypothesize that pediatric patients with intermediate/high-grade injuries can be safely managed with NOM. METHODS: All pediatric patients (younger than 18 years) registered in TQIP between 2013 and 2021 who suffered a grade III or IV pancreatic injury due to blunt trauma were included in the current study. Patient demographics, clinical characteristics, complications, and in-hospital mortality were compared between the different treatment strategies for pancreatic injury: NOM versus drainage and/or pancreatic resection. RESULTS: A total of 580 patients meeting the inclusion criteria were identified. A total of 416 pediatric patients suffered a grade III pancreatic injury; 79% (n = 332) were NOM, 7% (n = 27) received a drain, and 14% (n = 57) underwent a pancreatic resection. A further 164 patients suffered a grade IV pancreatic injury; 77% (n = 126) were NOM, 11% (n = 18) received a drain, and 12% (n = 20) underwent a pancreatic resection. No differences in overall injury severity or demographical data were observed between the treatment groups. No difference in in-hospital mortality was detected between the different management strategies. Patients who received a drain had a longer hospital length of stay. CONCLUSION: The majority of children with American Association for the Surgery of Trauma Organ Injury Scale grades III and IV pancreatic injuries are managed nonoperatively. Nonoperative management is a reasonable strategy for these injuries and results in equivalent in-hospital adverse outcome profiles as pancreatic drainage or resection with a shorter hospital length of stay. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Photoacoustic Imaging as a Novel Non-invasive Biomarker to Assess Intestinal Tissue Oxygenation and Motility in Neonatal Rats.

BACKGROUND: Within the premature infant intestine, oxygenation and motility play key physiological roles in healthy development and disease such as necrotizing enterocolitis. To date, there are limited techniques to reliably assess these physiological functions that are also clinically feasible for critically ill infants. To address this clinical need, we hypothesized that photoacoustic imaging (PAI) can provide non-invasive assessment of intestinal tissue oxygenation and motility to characterize intestinal physiology and health. METHODS: Ultrasound and photoacoustic images were acquired in 2-day and 4-day old neonatal rats. For PAI assessment of intestinal tissue oxygenation, an inspired gas challenge was performed using hypoxic, normoxic, and hyperoxic inspired oxygen (FiO2). For intestinal motility, oral administration of ICG contrast agent was used to compare control animals to an experimental model of loperamide-induced intestinal motility inhibition. RESULTS: PAI demonstrated progressive increases in oxygen saturation (sO2) as FiO2 increased, while the pattern of oxygen localization remained relatively consistent in both 2-day and 4-day old neonatal rats. Analysis of intraluminal ICG contrast enhanced PAI images yielded a map of the motility index in control and loperamide treated rats. From PAI analysis, loperamide significantly inhibited intestinal motility, with a 32.6% decrease in intestinal motility index scores in 4-day old rats. CONCLUSION: These data establish the feasibility and application of PAI to non-invasively and quantitatively measure intestinal tissue oxygenation and motility. This proof-of-concept study is an important first step in developing and optimizing photoacoustic imaging to provide valuable insight into intestinal health and disease to improve the care of premature infants.

Does the Timing of Surgical Intervention Impact Outcomes in Necrotizing Enterocolitis?

OBJECTIVES: The optimal time for intervention in surgical necrotizing enterocolitis (sNEC) remains to be elucidated. Surgical management varies between peritoneal drain (PD), laparotomy (LAP), and PD with subsequent LAP (PD + LAP). We propose that some infants with surgical NEC benefit from late (>48 h) operative intervention to allow for resuscitation. METHODS: A retrospective comparison of clinical information in infants with sNEC from 2012 to 2022 was performed. Early intervention was defined as less than 48 hours from time of NEC diagnosis to surgical intervention. RESULTS: 118 infants were identified, 92 underwent early intervention (62 LAP; 22 PD; 8 PD + LAP) and 26 underwent late intervention (20 LAP; 2 PD; 4 PD + LAP). Infants with early intervention were diagnosed younger (DOL 8 [6, 15] vs 20 [11, 26]; P=< .05) with more pneumoperitoneum (76% vs 23%; P=< .05). The early intervention group had a higher mortality (35% vs 15%; P=< .05). When excluding infants with pneumoperitoneum, the early intervention group had a higher mortality rate (10/22 (45%), 4/26 (15%); P < .05) and had more bowel resected (29 ± 17 cm vs 9 ± 8 cm; P < .05), with the same number of patients scoring above 3 on the MD7 criteria. CONCLUSION: Infants with NEC who underwent early surgical intervention had a higher mortality and more bowel resected. While this study has a provocative finding, it is severely limited by the non-specific 48-hour cut off. However, our data suggests that a period of medical optimization may improve outcomes in infants with sNEC and thus more in-depth studies are needed.

A Comparative Analysis of "Surgery First" vs. "Endoscopy First" for Pediatric Choledocholithiasis Presenting at the End of the Week.

BACKGROUND: Choledocholithiasis in children is commonly managed with an "endoscopy first" (EF) strategy (endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy (LC) under a separate anesthetic). Endoscopic Retrograde Cholangiopancreatography is limited at the end of the week (EoW). We hypothesize that a "surgery first" (SF) approach with LC, intraoperative cholangiogram (IOC), and possible laparoscopic common bile duct exploration (LCBDE) can decrease length of stay (LOS) and time to definitive intervention (TTDI). METHODS: This is a retrospective single-center cohort study conducted between 2018 and 2023 in pediatric patients with suspected choledocholithiasis. Work week (WW) presentation included admission between Monday and Thursday. Time to definitive intervention was defined as time to LC. RESULTS: 88 pediatric patients were identified, 61 managed with SF (33 WW and 28 EoW) and 27 managed with EF (18 WW and 9 EoW). Both SF groups had shorter mean LOS for WW and EoW presentation (64.5 h, 92.4 h, 112.9 h, and 113.0 h; P < .05). There was a downtreading TTDI in the SF groups (SF: WW 24.7 h and EoW 21.7 h; EF: WW 31.7 h and EoW 35.9 h; P = .11). 44 patients underwent LCBDE with similar success rates (91.6% WW and 85% EoW; P = 1.0). All EF patients received 2 procedures; 69% of SF patients were definitively managed with one. CONCLUSION: Children with choledocholithiasis at the EoW have a longer LOS and TTDI. These findings are amplified when children enter an EF treatment pathway. An SF approach results in shorter LOS with fewer procedures, regardless of the time of presentation.

Patient Safety and Radiation Exposure in Transcystic Laparoscopic Common Bile Duct Exploration: A CARES Working Group Multicenter Study.

BACKGROUND: Treatment of choledocholithiasis with laparoscopic cholecystectomy (LC) and intraoperative cholangiogram (IOC) ± transcystic laparoscopic common bile duct exploration (LCBDE) is associated with fewer procedures and shorter length of stay (LOS) compared to preoperative endoscopic retrograde cholangiopancreatography (ERCP) followed by LC. Fluoroscopy is required for both LCBDE and ERCP but fluoroscopic time (FT) and radiation dose (RD) in LCBDE has not been studied. METHODS: The Choledocholithiasis Alliance for Research, Education, and Surgery (CARES) Working Group conducted this retrospective study on pediatric patients with suspected choledocholithiasis who received IOC. Demographics, type of LCBDE, FT and RD during IOC ± LCBDE, were analyzed. Statistical analysis was completed using Microsoft Excel and R software. RESULTS: From five centers, 157 patients were identified (79 without LCBDE, 78 with LCBDE). Wire access into the duodenum was successful in 67 patients (86%) and 64 patients (82%) had successful duct clearance. Median FT for all LCBDE cases was 3.3 min [1.6, 6.7] and RD was 59.8 mGy [30.1, 125.0] with no difference between successful and unsuccessful duct clearance (66.7 mGy [29.0, 115.0], 55.8 mGy [35.8, 154.1], respectfully; p = 0.51). CONCLUSION: Although both ERCP and LCBDE approaches result in fluoroscopic radiation exposure, FT, and RD in LCBDE have not previously been studied and are inadequately described in ERCP. Limiting radiation exposure in children is essential and fluoroscopy stewardship is a key component of pediatric safety in LCBDE. LEVEL OF EVIDENCE: Level III.

Reducing MRCP Utilization Through a "Surgery First" Approach for Pediatric Choledocholithiasis: A CARES Working Group Retrospective Study.

BACKGROUND: Choledocholithiasis in children is rising and frequently managed with an endoscopy-first (EF) approach that utilizes endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy (LC). Magnetic resonance cholangiopancreatography (MRCP) is a resource intensive modality that often precedes ERCP to gain further assurance of choledocholithiasis prior to intervention. MRCP can lead to a longer length of stay (LOS) and strain healthcare resources. We hypothesized that the use of MRCP is decreased with a surgery-first (SF) approach. METHODS: The Choledocholithiasis Alliance for Research, Education, and Surgery (CARES) Working Group conducted this retrospective study on pediatric patients with suspected choledocholithiasis. SF patients underwent LC + intraoperative cholangiogram (IOC) ± laparoscopic common bile duct exploration (LCBDE). Imaging studies included ultrasound (US), MRCP, and computed tomography (CT). RESULTS: From seven institutions, 357 pediatric patients were identified. The SF (n = 220) group received fewer imaging studies then EF (n = 137) (1.29 vs. 1.62; p < 0.05). US was more commonly employed and the number of US and CT scans was similar. The SF group had lower MRCP utilization than EF (29% vs. 59%; p < 0.05). EF patients that received an MRCP had the longest LOS (4.0 d [2.4, 6.3]) compared to SF that did not (1.9 d [1.2, 3.2]) (p < 0.05). CONCLUSION: Children with choledocholithiasis managed with an EF approach receive more diagnostic imaging, especially MRCP. While MRCP remains a powerful diagnostic tool, a surgery-first approach can minimize the resource utilization and LOS associated with magnetic resonance imaging. LEVEL OF EVIDENCE: Level III.

Multi-institutional Analysis of Choledocholithiasis in Pediatric vs Adult Patients.

BACKGROUND: In adults, upfront intraoperative cholangiogram with laparoscopic common bile duct exploration (LCBDE) is well accepted for management of choledocholithiasis. Despite recent evidence supporting LCBDE utility in children, there has been hesitation to adopt this surgery first (SF) approach over ERCP first (EF) due to perceived technical challenges. We compared rates of successful stone clearance during LCBDE between adult and pediatric patients to evaluate if pediatric surgeons could anticipate similar rates of successful clearance. METHODS: A multicenter, retrospective review of pediatric (<18 years) and adult patients with choledocholithiasis managed from 2018 to 2024 was performed. Demographic and clinical data were obtained. Rate of successful duct clearance with LCBDE was compared. Surgical and endoscopic complications (infections, bleeding, pancreatitis, bile leak) were also compared. RESULTS: 724 patients, 333 (45.9%) pediatric and 391 (54.0%) adults, were included. The median age of pediatric vs adult patients was 15.2 years [13.1, 16.6] vs 55.5 years [34.1, 70.5], respectively. Of these, 201 (60.4%) pediatric vs 169 (43.2%) adult patients underwent SF, p < 0.001. LCBDE was attempted in 84 (41.7%) pediatric vs 140 (82.8%) adults, p = 0.002. LCBDE success was higher in pediatric vs adult patients (82.1% vs 71.4%, p = 0.004). Complications rates were similar however, pediatric patients who underwent EF had higher endoscopic complications (9.1% vs 3.6%, p = 0.03). CONCLUSION: LCBDE is highly successful in children vs adults with no increased surgical complications. This data, coupled with the limited ERCP access for children, supports that LCBDE is an equally effective tool for managing choledocholithiasis in children as is accepted in adults. LEVEL OF EVIDENCE: Level III.

A Novel Taxonomy of Intraoperative Cholangiograms in Suspected Choledocholithiasis: A Tool for Advancing Laparoscopic Common Bile Duct Exploration Outcomes Research.

BACKGROUND: Cholangiography for visualization of the biliary tree during laparoscopic cholecystectomy is an important diagnostic roadmap in the context of suspected choledocholithiasis (CDL). The renewed interest in transcystic laparoscopic common bile duct exploration (LCBDE) necessitates a general description of the range of CDL presentations. Our aim was to establish a novel classification system of intraoperative cholangiograms (IOCs) to advance research efforts in this field. METHODS: A novel cholangiogram classification system, featuring 8 distinct presentations of choledocholithiasis, was applied to a data set of 80 preintervention IOCs for suspected choledocholithiasis. The classification system is as follows: A (no common bile duct stones, duodenal filling present, and concern for air bubbles), B (no common bile duct stones, no duodenal filling, and concern for sludge), C1 (stone(s) < 2x size of cystic duct with duodenal filling), C2 (stone(s) < 2x size of cystic duct without duodenal filling), D1 (stone(s) ≥ 2x size of cystic duct with duodenal filling), D2 (stone(s) ≥ 2x size of cystic duct without duodenal filling), E1 (congenital anatomical variant and/or common duct stricture), and E2 (surgically altered biliary anatomy). RESULTS: Cholangiogram review yielded preintervention classifications for 6 of 8 variants (A-E): A (7.5%), B (3.75%), C1 (23.75%), C2 (42.5%), D1 (15%), and D2 (7.5%). Analysis of cystic duct diameter yielded no significant differences among classification groups, indicating no predominant pattern of cystic duct anatomy within a given classification. DISCUSSION: An IOC classification system for suspected choledocholithiasis is foundational to answering key clinical questions for transcystic laparoscopic common bile duct exploration.

Transcystic Laparoscopic Common Bile Duct Exploration for Pediatric Patients with Choledocholithiasis: A Multi-Center Study.

BACKGROUND: Patients with choledocholithiasis are often treated with endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy (LC). Upfront LC, intraoperative cholangiogram (IOC), and possible transcystic laparoscopic common bile duct exploration (LCBDE) could potentially avoid the need for ERCP. We hypothesized that upfront LC + IOC ± LCBDE will decrease length of stay (LOS) and the total number of interventions for children with suspected choledocholithiasis. METHODS: A multicenter, retrospective cohort study was performed on pediatric patients (<18 years) between 2018 and 2022 with suspected choledocholithiasis. Demographic and clinical data were compared for upfront LC + IOC ± LCBDE and possible postoperative ERCP (OR1st) versus preoperative ERCP prior to LC (OR2nd). Complications were defined as postoperative pancreatitis, recurrent choledocholithiasis, bleeding, or abscess. RESULTS: Across four centers, 252 children with suspected choledocholithiasis were treated with OR1st (n = 156) or OR2nd (n = 96). There were no differences in age, gender, or body mass index. Of the LCBDE patients (72/156), 86% had definitive intraoperative management with the remaining 14% requiring postoperative ERCP. Complications were fewer and LOS was shorter with OR1st (3/156 vs. 15/96; 2.39 vs 3.84 days, p < 0.05). CONCLUSION: Upfront LC + IOC ± LCBDE for children with choledocholithiasis is associated with fewer ERCPs, lower LOS, and decreased complications. Postoperative ERCP remains an essential adjunct for patients who fail LCBDE. Further educational efforts are needed to increase the skill level for IOC and LCBDE in pediatric patients with suspected choledocholithiasis. LEVEL OF EVIDENCE: Level III.

"Surgery First" vs. "Endoscopy First" for Pediatric Choledocholithiasis Presenting at the End of the Week - A CARES Working Group Study.

BACKGROUND: Choledocholithiasis in children is commonly managed with an "endoscopy-first" (EF) strategy (endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy (LC)). Because ERCP availability is often limited at the end of the week (EoW), we hypothesized that a "surgery-first" (SF) approach (LC with intraoperative cholangiogram (IOC) ± transcystic laparoscopic common bile exploration (LCBDE)) would decrease length of stay (LOS) and time to definitive intervention (TTDI). METHODS: A multicenter, retrospective cohort study was conducted on pediatric patients from 2018 to 2023 with suspected choledocholithiasis. Work week (WW) presentation was defined as admission between Monday to Thursday. TTDI was defined as time to LC or postoperative ERCP (if required). RESULTS: Among seven hospitals, there were 354 pediatric patients; 217 (61%) managed with SF (125 WW, 92 EoW) and 137 (39%) managed with EF (74 WW, 63 EoW). SF groups had a shorter LOS for both WW and EoW presentation (60.2 h and 58.3 h vs 88.5 h and 93.6 h respectively; p < 0.05). TTDI decreased in SF (26.4 h and 28.9 h vs 61.4 h and 72.8 h; p < 0.05). All EF patients underwent at least two anesthetics (preoperative ERCP followed by LC) while the majority (79%) of the SF group had only one procedure (LC + IOC ± LCBDE). CONCLUSION: Children who present with choledocholithiasis at EoW have a longer LOS and TTDI. These findings are amplified when children enter an EF pathway. A surgery-first approach results in fewer procedures, decreased TTDI, and shorter LOS, regardless of the time of presentation. LEVEL OF EVIDENCE: Level III.

Oral 'Board Style' Examination for Surgery Clerkship.

Evaluating medical students during surgical clerkships relies on multifactorial methods of evaluation. Clinical evaluations, combined with standardized multiple-choice exams, are often the foundation of evaluation highlighting the challenge of combining subjective and objective measurements. Oral board exams are standard amongst medical certification and employ an additional element to evaluate students more holistically. Course evaluations from years that incorporated an oral board exam were compared to a year that omitted the exam. We found course satisfaction was higher in the years that included the oral exam (3.25 /5) than years without the oral board exam (3/ 5). The oral exam adds a novel element to the evaluation of a medical student that allows for a comprehensive understanding of a student's fund of knowledge and helps prepare them for future board certifications. Because students have an opportunity to demonstrate knowledge in a standard, more comprehensive format, they have higher satisfaction with the course.

Mesothelial Inclusion Cyst in an Infant with Beckwith-Weidemann Syndrome.

Mesothelial inclusion cysts are rare benign tumors not frequently reported in the literature. When reported, they are primarily found in adults. One report from 2006 reports an association with Beckwith-Weideman syndrome, but no other reported cases discuss this correlation. We describe a case of an infant with Beckwith-Weideman syndrome who, in the setting of omphalocele repair, was found to have hepatic cysts with pathology revealing mesothelial inclusion cysts.

Storage Practices, Devices, and Presence of Children Among Owners of Firearms: Informing Pediatric Firearm Safety.

BACKGROUND: Firearm injury is the leading cause of death in children and prevention is the most effective method to reduce severe morbidity and mortality. Injury prevention programs have used community firearm lock giveaway events to promote safe firearm storage practices. The locks are generally simple and inexpensive devices suitable for mass distribution but may not possess the owner-desired attributes for use in the home. Because data on owner preferences for firearm lock type is lacking, we conducted a community survey to inform firearm safety outreach efforts. METHODS: We performed an anonymous cross-sectional survey at a large community fair. We elicited responses regarding reasons for firearm ownership, current storage practices, and preferences for firearm storage devices. Participants were offered a choice of a free trigger lock or cable lock and education on its use. RESULTS: Two-hundred and sixty-seven of 394 (67.7%) respondents reported firearm ownership, with 64.8% reporting children in the home regularly. Most (60.7%) owned handguns and cited personal protection as the main reason for ownership (88.4%). The ability to store the firearm loaded and the need for rapid access were identified as the main storage considerations. Respondents preferred trigger locks over cable locks at a rate of almost 2:1. CONCLUSIONS: The majority of firearm owners had handguns for self-defense. Owners preferred simple locking mechanisms that allowed the firearm to remain loaded. The pragmatic pediatric injury prevention program will include firearm owners' preferences when considering which lock to purchase and distribute during firearm injury prevention programs. LEVEL OF EVIDENCE: IV, Epidemiological.

Photoacoustic Imaging as a Novel Non-Invasive Biomarker to Assess Intestinal Tissue Oxygenation and Motility in Neonatal Rats.

Background: Within the premature infant intestine, oxygenation and motility play key physiological roles in healthy development and disease such as necrotizing enterocolitis. To date, there are limited techniques to reliably assess these physiological functions that are also clinically feasible for critically ill infants. To address this clinical need, we hypothesized that photoacoustic imaging (PAI) can provide non-invasive assessment of intestinal tissue oxygenation and motility to characterize intestinal physiology and health. Methods: Ultrasound and photoacoustic images were acquired in 2-day and 4-day old neonatal rats. For PAI assessment of intestinal tissue oxygenation, an inspired gas challenge was performed using hypoxic, normoxic, and hyperoxic inspired oxygen (FiO2). For intestinal motility, oral administration of ICG contrast agent was used to compare control animals to an experimental model of loperamide-induced intestinal motility inhibition. Results: PAI demonstrated progressive increases in oxygen saturation (sO2) as FiO2 increased, while the pattern of oxygen localization remained relatively consistent in both 2-day and 4-day old neonatal rats. Analysis of intraluminal ICG contrast enhanced PAI images yielded a map of the motility index in control and loperamide treated rats. From PAI analysis, loperamide significantly inhibited intestinal motility, with a 32.6% decrease in intestinal motility index scores in 4-day old rats. Conclusion: These data establish the feasibility and application of PAI to non-invasively and quantitatively measure intestinal tissue oxygenation and motility. This proof-of-concept study is an important first step in developing and optimizing photoacoustic imaging to provide valuable insight into intestinal health and disease to improve the care of premature infants. Highlights: Intestinal tissue oxygenation and intestinal motility are important biomarkers of intestinal physiology in health and disease of premature infants.This proof-of-concept preclinical rat study is the first to report application of photoacoustic imaging for the neonatal intestine.Photoacoustic imaging is demonstrated as a promising non-invasive diagnostic imaging method for quantifying intestinal tissue oxygenation and intestinal motility in premature infants.

Photoacoustic Imaging for Non-Invasive Assessment of Physiological Biomarkers of Intestinal Injury in Experimental Necrotizing Enterocolitis.

Background: Necrotizing enterocolitis (NEC) is an often-lethal disease of the premature infants' intestinal tract that is exacerbated by significant difficulties in early and accurate diagnosis. In NEC disease, the intestine often exhibits hypoperfusion and dysmotility, which contributes to advanced disease pathogenesis. However, these physiological features cannot be accurately and quantitively assessed within the current constraints of imaging modalities frequently used in the clinic (plain film X-ray and ultrasound). We have previously demonstrated the ability of photoacoustic imaging (PAI) to non-invasively and quantitively assess intestinal tissue oxygenation and motility in a healthy neonatal rat model. As a first-in-disease application, we evaluated NEC pathogenesis using PAI to assess intestinal health biomarkers in a preclinical neonatal rat experimental model of NEC. Methods: NEC was induced in neonatal rat pups from birth to 4 days old via hypertonic formula feeding, full-body hypoxic stress, and lipopolysaccharide administration to mimic bacterial colonization. Healthy breastfed (BF) controls and NEC rat pups were imaged at 2- and 4-days old. Intestinal tissue oxygen saturation was measured with PAI imaging for oxy- and deoxyhemoglobin levels. To measure intestinal motility, ultrasound and co-registered PAI cine recordings were used to capture intestinal peristalsis motion and contrast agent (indocyanine green) transit within the intestinal lumen. Additionally, both midplane two-dimensional and volumetric three-dimensional imaging acquisitions were assessed for oxygenation and motility. Results: NEC pups showed a significant decrease of intestinal tissue oxygenation as compared to healthy BF controls at both ages (2-days old: 55.90% +/- 3.77% vs 44.12% +/- 7.18%; 4-days old: 56.13% +/- 3.52% vs 38.86% +/- 8.33%). Intestinal motility, assessed using a computational intestinal deformation analysis, demonstrated a significant reduction in the intestinal motility index in both early (2-day) and established (4-day) NEC. Extensive NEC damage was confirmed with histology and dysmotility was confirmed by small intestinal transit assay. Conclusions: This study presents PAI as a successful emerging diagnostic imaging modality for both intestinal tissue oxygenation and intestinal motility disease hallmarks in a rat NEC model. PAI presents enormous significance and potential for fundamentally changing current clinical paradigms for detecting and monitoring intestinal pathologies in the premature infant.