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1.
Diabetes Care ; 47(3): 393-400, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38151474

ABSTRACT

OBJECTIVE: This multicenter prospective cohort study compared pancreas volume as assessed by MRI, metabolic scores derived from oral glucose tolerance testing (OGTT), and a combination of pancreas volume and metabolic scores for predicting progression to stage 3 type 1 diabetes (T1D) in individuals with multiple diabetes-related autoantibodies. RESEARCH DESIGN AND METHODS: Pancreas MRI was performed in 65 multiple autoantibody-positive participants enrolled in the Type 1 Diabetes TrialNet Pathway to Prevention study. Prediction of progression to stage 3 T1D was assessed using pancreas volume index (PVI), OGTT-derived Index60 score and Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), and a combination of PVI and DPTRS. RESULTS: PVI, Index60, and DPTRS were all significantly different at study entry in 11 individuals who subsequently experienced progression to stage 3 T1D compared with 54 participants who did not experience progression (P < 0.005). PVI did not correlate with metabolic testing across individual study participants. PVI declined longitudinally in the 11 individuals diagnosed with stage 3 T1D, whereas Index60 and DPTRS increased. The area under the receiver operating characteristic curve for predicting progression to stage 3 from measurements at study entry was 0.76 for PVI, 0.79 for Index60, 0.79 for DPTRS, and 0.91 for PVI plus DPTRS. CONCLUSIONS: These findings suggest that measures of pancreas volume and metabolism reflect distinct components of risk for developing stage 3 type 1 diabetes and that a combination of these measures may provide superior prediction than either alone.


Subject(s)
Diabetes Mellitus, Type 1 , Humans , Diabetes Mellitus, Type 1/diagnosis , Prospective Studies , Pancreas/diagnostic imaging , Pancreas/metabolism , Risk Factors , Autoantibodies , Magnetic Resonance Imaging
2.
J Perinatol ; 43(9): 1131-1138, 2023 09.
Article in English | MEDLINE | ID: mdl-37391509

ABSTRACT

OBJECTIVE: Congenital Diaphragmatic Hernia (CDH) is diagnosed prenatally in ~60% of cases. Prenatal measures typically guide management and prognostication. Simple postnatal prognosticators are needed when prenatal diagnosis is lacking. We hypothesized that preoperative orogastric tube (OGT) tip position relative to the contralateral diaphragm correlates with defect severity, resource utilization, and clinical outcomes regardless of diagnostic status. STUDY DESIGN: 150 neonates with left-posterolateral CDH were analyzed. Impact of intrathoracic and intraabdominal preoperative tip position on clinical outcomes was compared. RESULTS: Ninety-nine neonates were prenatally diagnosed. Overall, intrathoracic position significantly correlated with larger diaphragmatic defects, advanced postnatal pulmonary support requirements (HFOV, pulmonary vasodilators, and ECMO), operative complexity, longer hospitalization, and poorer survival to discharge. These observations persisted when analyzing only cases lacking prenatal diagnosis. CONCLUSIONS: Preoperative OGT tip position predicts defect severity, resource utilization, and outcomes in CDH. This observation enhances postnatal prognostication and care planning for neonates without a prenatal diagnosis.


Subject(s)
Hernias, Diaphragmatic, Congenital , Pregnancy , Infant, Newborn , Female , Humans , Hernias, Diaphragmatic, Congenital/diagnostic imaging , Hernias, Diaphragmatic, Congenital/surgery , Prenatal Diagnosis , Radiography , Hospitalization , Retrospective Studies
3.
Pediatr Radiol ; 53(5): 825-826, 2023 05.
Article in English | MEDLINE | ID: mdl-37067566
4.
J Clin Endocrinol Metab ; 108(10): 2699-2707, 2023 09 18.
Article in English | MEDLINE | ID: mdl-36938587

ABSTRACT

CONTEXT: Individuals with type 1 diabetes (T1D) have a smaller pancreas, but longitudinal changes in pancreas size and shape are unclear. OBJECTIVE: We monitored changes in pancreas size and shape after diagnosis with T1D. DESIGN: We conducted a prospective cohort study at an academic medical center between 2014 and 2022. PATIENTS AND HEALTHY CONTROLS: Individuals with T1D (n = 91) or controls (n = 90) underwent magnetic resonance imaging (MRI) of the pancreas, including longitudinal MRI in 53 individuals with new-onset T1D. INTERVENTION: Interventions included MRI and continuous glucose monitoring (CGM). MAIN OUTCOME MEASURES: Pancreas size and shape were measured from MRI. For participants who used CGM, measures of glycemic variability were calculated. RESULTS: On longitudinal imaging, pancreas volume and pancreas volume index normalized for body weight declined during the first year after diagnosis. Pancreas volume index continued to decline through the fifth year after diagnosis. A cross-sectional study of individuals with diabetes duration up to 60 years demonstrated that pancreas size in adults negatively correlated with age and disease duration, whereas pancreas volume and pancreas volume index remained stable in controls. Pancreas volume index correlated inversely with low blood glucose index, a measure of risk for hypoglycemia. Pancreas shape was altered in individuals with T1D and further diverged from controls over the first 5 years after diagnosis. Pancreas size and shape are altered in nondiabetic individuals at genetic risk for T1D. Combined pancreas size and shape analysis better distinguished the pancreas of individuals with T1D from controls than size alone. CONCLUSIONS: Pancreas size declines most rapidly near the clinical diagnosis of T1D and continues to decline throughout adulthood. Declines in pancreas size are accompanied by changes in pancreas shape.


Subject(s)
Diabetes Mellitus, Type 1 , Adult , Humans , Blood Glucose , Blood Glucose Self-Monitoring/methods , Cross-Sectional Studies , Prospective Studies , Pancreas/diagnostic imaging , Magnetic Resonance Imaging
5.
Diabetes Care ; 46(4): 773-776, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36724370

ABSTRACT

OBJECTIVE: To determine the mechanism of reduced pancreas size in type 1 diabetes and the significance of islet-derived insulin in pancreatic growth. RESEARCH DESIGN AND METHODS: Using a validated and standardized MRI protocol, we measured pancreas volume and shape in a family with an autosomal-dominant insulin gene mutation that results in insulin deficiency similar in severity to that of type 1 diabetes but without autoimmunity. DNA sequencing confirmed the mutation in all four affected individuals and none of the four control family members. Insulin secretory capacity was determined by measuring postprandial urinary C-peptide. RESULTS: Family members with this form of monogenic diabetes had a markedly smaller pancreas and a severely impaired postprandial C-peptide level than family members without diabetes. CONCLUSIONS: These results suggest that severe insulin deficiency, rather than islet-directed autoimmunity, leads to reduced pancreas size in type 1 diabetes and that insulin is a major trophic factor for the exocrine pancreas.


Subject(s)
Diabetes Mellitus, Type 1 , Insulin , Pancreas , Diabetes Mellitus, Type 1/diagnostic imaging , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/pathology , Organ Size , Insulin/deficiency , Insulin/genetics , Pancreas/diagnostic imaging , Pancreas/pathology , Pedigree , Magnetic Resonance Imaging , Heterozygote , Humans , Male , Female , Adult , Middle Aged , Mutation
6.
J Interprof Care ; 37(2): 316-319, 2023.
Article in English | MEDLINE | ID: mdl-36739558

ABSTRACT

Students in their second year of the Vanderbilt Program of Interprofessional Learning (VPIL) complete team-based quality improvement (QI) projects in their assigned clinic as part of the core curriculum. This report describes the creation and implementation of the student teams' QI curriculum and investigates how clinical preceptors view the project impact. Between 2012-2019, the VPIL teams designed and implemented 69 improvement projects. Improvement projects fell primarily into three categories: improving clinic care delivery (n = 25, 36%), patient education and health coaching (n = 21, 30%), and quality measures such as screening tests/prophylaxis (n = 10, 14%). Clinic preceptors received a survey about the sustainability and effectiveness of the projects. Survey feedback was received from 44/69 (64%) preceptors. Many (70%) projects resulted in perceived improvements, and some projects (34%) had improvements that are still in use. Despite barriers and challenges, interprofessional student teams can successfully learn the basics of QI and work together to design and implement a project. These projects have the potential to make meaningful changes in clinic practices and are helpful to the clinic preceptors.


Subject(s)
Internship and Residency , Quality Improvement , Humans , Interprofessional Relations , Curriculum , Students
7.
Am Surg ; 89(5): 1449-1456, 2023 May.
Article in English | MEDLINE | ID: mdl-34855532

ABSTRACT

BACKGROUND: Solid pseudopapillary tumors (SPTs) of the pancreas arise rarely in children, are often large, and can associate intimately with splenic vessels. Splenic preservation is a fundamental consideration when resecting distal SPT. Occasionally, the main splenic vessels must be divided to resect the SPT with negative margins, but the spleen can be preserved if the short gastric vessels remain intact (ie, Warshaw procedure). The purpose of this study was to evaluate outcomes of distal pancreatectomy (DP) for SPT in children and to highlight 2 cases of splenic preservation using the Warshaw procedure. METHODS: Patients 19 years and younger who were treated at a single children's hospital between July 2004 and January 2021 were examined. Patient characteristics were collected from the electronic medical record. A pediatric radiologist calculated SPT and pre- and post-operative (ie, non-infarcted) splenic volumes. RESULTS: Eleven patients received DP for SPT. Six DPs were performed open and 5 laparoscopically. The spleen was preserved in 3 open and 4 laparoscopic DPs. A laparoscopic Warshaw procedure was performed in 2 patients. Laparoscopic resection associated with less frequent epidural use (P = .015), shorter time to full diet (P = .030), and post-operative length of stay (P = .009), compared to open resection. Average residual splenic volume after the laparoscopic Warshaw procedure was 70% of preoperative volume. DISCUSSION: Laparoscopic DP for pediatric SPT achieved similar oncologic goals to open resection. Splenic preservation was feasible with laparoscopy in most cases and was successfully supplemented with the Warshaw procedure, which has not been previously reported for SPT resection in children.


Subject(s)
Laparoscopy , Pancreatic Neoplasms , Humans , Child , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/pathology , Pancreas/surgery , Spleen/surgery , Pancreatectomy/methods , Laparoscopy/methods , Treatment Outcome
8.
BMC Med Imaging ; 22(1): 5, 2022 01 05.
Article in English | MEDLINE | ID: mdl-34986790

ABSTRACT

Pancreas volume is reduced in individuals with diabetes and in autoantibody positive individuals at high risk for developing type 1 diabetes (T1D). Studies investigating pancreas volume are underway to assess pancreas volume in large clinical databases and studies, but manual pancreas annotation is time-consuming and subjective, preventing extension to large studies and databases. This study develops deep learning for automated pancreas volume measurement in individuals with diabetes. A convolutional neural network was trained using manual pancreas annotation on 160 abdominal magnetic resonance imaging (MRI) scans from individuals with T1D, controls, or a combination thereof. Models trained using each cohort were then tested on scans of 25 individuals with T1D. Deep learning and manual segmentations of the pancreas displayed high overlap (Dice coefficient = 0.81) and excellent correlation of pancreas volume measurements (R2 = 0.94). Correlation was highest when training data included individuals both with and without T1D. The pancreas of individuals with T1D can be automatically segmented to measure pancreas volume. This algorithm can be applied to large imaging datasets to quantify the spectrum of human pancreas volume.


Subject(s)
Deep Learning , Diabetes Mellitus, Type 1/diagnostic imaging , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Pancreas/diagnostic imaging , Adolescent , Algorithms , Diabetes Mellitus, Type 1/pathology , Humans , Imaging, Three-Dimensional/methods , Male , Organ Size , Pancreas/pathology , Retrospective Studies
9.
PLoS One ; 16(8): e0256029, 2021.
Article in English | MEDLINE | ID: mdl-34428220

ABSTRACT

Magnetic resonance imaging (MRI) has detected changes in pancreas volume and other characteristics in type 1 and type 2 diabetes. However, differences in MRI technology and approaches across locations currently limit the incorporation of pancreas imaging into multisite trials. The purpose of this study was to develop a standardized MRI protocol for pancreas imaging and to define the reproducibility of these measurements. Calibrated phantoms with known MRI properties were imaged at five sites with differing MRI hardware and software to develop a harmonized MRI imaging protocol. Subsequently, five healthy volunteers underwent MRI at four sites using the harmonized protocol to assess pancreas size, shape, apparent diffusion coefficient (ADC), longitudinal relaxation time (T1), magnetization transfer ratio (MTR), and pancreas and hepatic fat fraction. Following harmonization, pancreas size, surface area to volume ratio, diffusion, and longitudinal relaxation time were reproducible, with coefficients of variation less than 10%. In contrast, non-standardized image processing led to greater variation in MRI measurements. By using a standardized MRI image acquisition and processing protocol, quantitative MRI of the pancreas performed at multiple locations can be incorporated into clinical trials comparing pancreas imaging measures and metabolic state in individuals with type 1 or type 2 diabetes.


Subject(s)
Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/standards , Pancreas/diagnostic imaging , Adult , Diffusion Magnetic Resonance Imaging/methods , Female , Healthy Volunteers , Humans , Image Processing, Computer-Assisted , Male , Phantoms, Imaging , Prospective Studies , Reproducibility of Results
10.
Sci Rep ; 10(1): 4767, 2020 03 16.
Article in English | MEDLINE | ID: mdl-32179809

ABSTRACT

Reduced pancreas volume, as measured by non-contrast magnetic resonance imaging (MRI), is observed in individuals with newly-diagnosed type 1 diabetes (T1D) and declines over the first year after diagnosis. In this study, we determined the repeatability and inter-reader reproducibility of pancreas volume measurements by MRI. Test-retest scans in individuals with or without T1D (n = 16) had an intraclass correlation coefficient (ICC) of 0.985 (95% CI 0.961 to 0.995) for pancreas volume. Independent pancreas outlines by two board-certified radiologists (n = 30) yielded an ICC of 0.945 (95% CI 0.889 to 0.973). The mean Dice coefficient, a measurement of the degree of overlap between pancreas regions of interest between the two readers, was 0.77. Prandial state did not influence pancreatic measurements, as stomach volume did not correlate with pancreas volume. These data demonstrate that MRI measurements of pancreas volume between two readers are repeatable and reproducible with ICCs that correspond to excellent clinical significance (ICC > 0.9), are not related to changes in stomach volume, and could be a useful tool for clinical investigation of diabetes and other pancreas pathologies.


Subject(s)
Diabetes Mellitus, Type 1/diagnostic imaging , Diabetes Mellitus, Type 1/pathology , Magnetic Resonance Imaging/methods , Pancreas/diagnostic imaging , Pancreas/pathology , Adolescent , Adult , Child , Female , Humans , Male , Organ Size , Reproducibility of Results , Young Adult
11.
Acad Med ; 95(4): 553-558, 2020 04.
Article in English | MEDLINE | ID: mdl-31876566

ABSTRACT

PROBLEM: Designing and sustaining a longitudinal, clinic-based interprofessional learning experience is logistically challenging, which has limited the educational opportunities available in health professions schools. The authors discuss the Vanderbilt Program in Interprofessional Learning (VPIL), which addresses some of the challenges facing clinic-based interprofessional experiences. APPROACH: VPIL places first- and second-year students from 4 professional degree programs (medicine, nursing, pharmacy, social work) in Nashville, Tennessee, on teams where they work and learn together in authentic clinical environments over a 2-year period. The program was implemented in 2010 and includes 3 components: a summer immersion experience, seminar-based classroom and simulation sessions, and a weekly clinical experience. Students also complete a capstone quality improvement project. VPIL administrators have set up structures at the institutional, clinic, faculty, and student levels that have contributed to the sustainability of the program. OUTCOMES: Between 2010 and 2019, VPIL admitted 398 students who participated on 91 clinical teams. In addition, 55 clinical preceptors and 12 core faculty trained students for future collaborative practice. The program has received consistently high ratings from students, who have produced 69 quality improvement projects at their clinics. These projects have addressed aspects of the care delivery process and produced durable materials, showing that the program has contributed to important innovations in the health system. NEXT STEPS: VPIL faculty continue to improve the curriculum and administrative structures and work to expand the program to reach a wider variety of health professions students. Going forward, lessons from the program could assist educators in creating opportunities for students to learn interprofessionally and deliver high value health care in increasingly complex delivery systems.


Subject(s)
Education, Medical, Undergraduate/methods , Education, Nursing/methods , Education, Pharmacy/methods , Interdisciplinary Placement , Social Work/education , Curriculum , Humans , Tennessee
12.
J Pediatr Surg ; 54(6): 1184-1191, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30885556

ABSTRACT

BACKGROUND: The current neuroblastoma (NBL) staging system employs image-defined risk factors (IDRFs) to assess numerous anatomic features, but the impact of IDRFs on surgical and oncologic outcomes is unclear. METHODS: The Vanderbilt Cancer Registry identified children treated for NBL from 2002 to 2017. Tumor volume (TV) and IDRFs were measured radiographically at diagnosis and before resection. Perioperative and oncologic outcomes were evaluated. RESULTS: At diagnosis of 106 NBL, 61% were IDRF positive. MYCN-amplified and undifferentiated NBL had more IDRFs than nonamplified and more differentiated tumors (p = 0.001 and p = 0.01). Of 86 NBLs resected, 43% were IDRF positive, which associated with higher stage, risk, and TV (each p < 0.001). The presence of IDRF at resection was also associated with increased blood loss (p < 0.001), longer operating times (p < 0.001), greater incidence of intraoperative complications (p = 0.03), more frequent ICU admissions postoperatively (p < 0.001), and longer hospital stays (p < 0.001). IDRF negative and positive tumors did not have significantly different rates of gross total resection (p = 0.2). Five-year relapse-free and overall survival was similar for IDRF negative and positive NBL (p = 0.9 and p = 0.8). CONCLUSIONS: IDRFs at diagnosis were associated with larger, less differentiated, advanced stage, and higher risk NBL and at resection with increased operative difficulty and perioperative morbidity. However, the frequency of gross total resection and patient survival after resection were not associated with the presence of IDRFs. TYPE OF STUDY: Retrospective cohort study. LEVEL OF EVIDENCE: Level III.


Subject(s)
Neoplasm Staging , Neuroblastoma , Disease-Free Survival , Humans , Neoplasm Staging/methods , Neoplasm Staging/statistics & numerical data , Neuroblastoma/diagnostic imaging , Neuroblastoma/epidemiology , Neuroblastoma/mortality , Neuroblastoma/surgery , Retrospective Studies , Risk Factors
13.
Diabetes Care ; 42(2): 248-257, 2019 02.
Article in English | MEDLINE | ID: mdl-30552135

ABSTRACT

OBJECTIVE: This study investigated the temporal dynamics of pancreas volume and microstructure in children and adolescents with recent-onset type 1 diabetes (T1D) and individuals without diabetes, including a subset expressing autoantibodies associated with the early stages of T1D. RESEARCH DESIGN AND METHODS: MRI was performed in individuals with recent-onset stage 3 T1D (n = 51; median age 13 years) within 100 days after diagnosis (mean 67 days), 6 months, and 1 year postdiagnosis. Longitudinal MRI measurements were also made in similarly aged control participants (n = 57) and in autoantibody-positive individuals without diabetes (n = 20). The MRI protocol consisted of anatomical imaging to determine pancreas volume and quantitative MRI protocols interrogating tissue microstructure and composition. RESULTS: Within 100 days of diabetes onset, individuals with T1D had a smaller pancreas (median volume 28.6 mL) than control participants (median volume 48.4 mL; P < 0.001), including when normalized by individual weight (P < 0.001). Longitudinal measurements of pancreas volume increased in control participants over the year, consistent with adolescent growth, but pancreas volume declined over the first year after T1D diagnosis (P < 0.001). In multiple autoantibody-positive individuals, the pancreas volume was significantly larger than that of the T1D cohort (P = 0.017) but smaller than that of the control cohort (P = 0.04). Diffusion-weighted MRI showed that individuals with recent-onset T1D had a higher apparent diffusion coefficient (P = 0.012), suggesting a loss of cellular structural integrity, with heterogeneous pancreatic distribution. CONCLUSIONS: These results indicate that pancreas volume is decreased in stages 1, 2, and 3 of T1D and decreases during the first year after diabetes onset and that this loss of pancreatic volume is accompanied by microstructural changes.


Subject(s)
Diabetes Mellitus, Type 1/diagnosis , Pancreas/diagnostic imaging , Pancreas/pathology , Adolescent , Adult , Atrophy/diagnosis , Atrophy/etiology , Autoantibodies/analysis , Autoantibodies/blood , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/pathology , Female , Glucose Tolerance Test , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Organ Size , Pancreas/ultrastructure , Time Factors , Young Adult
14.
Article in English | MEDLINE | ID: mdl-29887665

ABSTRACT

Abdominal image segmentation is a challenging, yet important clinical problem. Variations in body size, position, and relative organ positions greatly complicate the segmentation process. Historically, multi-atlas methods have achieved leading results across imaging modalities and anatomical targets. However, deep learning is rapidly overtaking classical approaches for image segmentation. Recently, Zhou et al. showed that fully convolutional networks produce excellent results in abdominal organ segmentation of computed tomography (CT) scans. Yet, deep learning approaches have not been applied to whole abdomen magnetic resonance imaging (MRI) segmentation. Herein, we evaluate the applicability of an existing fully convolutional neural network (FCNN) designed for CT imaging to segment abdominal organs on T2 weighted (T2w) MRI's with two examples. In the primary example, we compare a classical multi-atlas approach with FCNN on forty-five T2w MRI's acquired from splenomegaly patients with five organs labeled (liver, spleen, left kidney, right kidney, and stomach). Thirty-six images were used for training while nine were used for testing. The FCNN resulted in a Dice similarity coefficient (DSC) of 0.930 in spleens, 0.730 in left kidneys, 0.780 in right kidneys, 0.913 in livers, and 0.556 in stomachs. The performance measures for livers, spleens, right kidneys, and stomachs were significantly better than multi-atlas (p < 0.05, Wilcoxon rank-sum test). In a secondary example, we compare the multi-atlas approach with FCNN on 138 distinct T2w MRI's with manually labeled pancreases (one label). On the pancreas dataset, the FCNN resulted in a median DSC of 0.691 in pancreases versus 0.287 for multi-atlas. The results are highly promising given relatively limited training data and without specific training of the FCNN model and illustrate the potential of deep learning approaches to transcend imaging modalities.

15.
Surgery ; 164(2): 333-343, 2018 08.
Article in English | MEDLINE | ID: mdl-29751968

ABSTRACT

BACKGROUND: Embryonal tumors arise typically in infants and young children and are often massive at presentation. Operative resection is a cornerstone in the multimodal treatment of embryonal tumors but potentially disrupts therapeutic timelines. When used appropriately, minimally invasive surgery can minimize treatment delays. The oncologic integrity and safety attainable with minimally invasive resection of embryonal tumors, however, remains controversial. METHODS: Query of the Vanderbilt Cancer Registry identified all children treated for intracavitary, embryonal tumors during a 15-year period. Tumors were assessed radiographically to measure volume (mL) and image-defined risk factors (neuroblastic tumors only) at time of diagnosis, and at preresection and postresection. Patient and tumor characteristics, perioperative details, and oncologic outcomes were compared between minimally invasive surgery and open resection of tumors of comparable size. RESULTS: A total of 202 patients were treated for 206 intracavitary embryonal tumors, of which 178 were resected either open (n = 152, 85%) or with minimally invasive surgery (n = 26, 15%). The 5-year, relapse-free, and overall survival were not significantly different after minimally invasive surgery or open resection of tumors having a volume less than 100 mL, corresponding to the largest resected with minimally invasive surgery (P = .249 and P = .124, respectively). No difference in margin status or lymph node sampling between the 2 operative approaches was detected (p = .333 and p = .070, respectively). Advantages associated with minimally invasive surgery were decreased blood loss (P < .001), decreased operating time (P = .002), and shorter hospital stay (P < .001). Characteristically, minimally invasive surgery was used for smaller volume and earlier stage neuroblastic tumors without image-defined risk factors. CONCLUSION: When selected appropriately, minimally invasive resection of pediatric embryonal tumors, particularly neuroblastic tumors, provides acceptable oncologic integrity. Large tumor volume, small patient size, and image-defined risk factors may limit the broader applicability of minimally invasive surgery.


Subject(s)
Neoplasms, Germ Cell and Embryonal/surgery , Child, Preschool , Early Diagnosis , Female , Humans , Infant , Male , Minimally Invasive Surgical Procedures , Neoadjuvant Therapy , Neoplasms, Germ Cell and Embryonal/diagnostic imaging , Neoplasms, Germ Cell and Embryonal/mortality , Neuroblastoma/mortality , Neuroblastoma/surgery , Registries , Tennessee/epidemiology , Tomography, X-Ray Computed , Treatment Outcome , Ultrasonography, Prenatal
16.
J Pediatr Orthop ; 38(5): 249-253, 2018.
Article in English | MEDLINE | ID: mdl-27280894

ABSTRACT

BACKGROUND: Factors that impact radiation exposure during operative fixation of pediatric supracondylar humerus (SCH) fractures have been investigated; however, no studies have measured the equivalent dose at the patient's radiosensitive organs. Our hypothesis was that intraoperative fluoroscopy exposes pediatric patients to a significant radiation load and lead shielding of radiosensitive organs is important. The goal of the study was to quantify the patient's radiation exposure during the procedure by measuring the radiation load at the thyroid and gonads. METHODS: A prospective quality improvement project of radiation exposure during percutaneous fixation of isolated SCH fractures was performed over a 4-week period. The c-arm image intensifier was used as the operating table and radiation dosimeters were positioned over the thyroid and gonadal lead shields. Fluoroscopy times were recorded, doses were calculated, and the dosimeters were analyzed. To assure that the prospective cohort was representative of a larger population of SCH fractures, demographics and fluoroscopy time of the prospective cohort were compared with a 12-month retrospective cohort in which dosimetry was not performed. RESULTS: Prospective cohort-18 patients with type 2 (8) and type 3 (10) fractures were prospectively studied with intraoperative measurement of thyroid and gonadal radiation equivalent doses. Mean age was 4.9 years (1.9 to 9.5 y) and mean weight was 21.4 kg (13.1 to 33.5 kg). Mean fluoroscopy time was 65.0 seconds (25.3 to 168.4 s), and absorbed skin dose at the elbow was 0.47 mGy (0.18 to 1.21 mGy). The radiation dosimeters overlying the thyroid and gonads measured minimal radiation indicating equivalent doses of <0.01 mSv for all patients in the prospective cohort.Retrospective cohort-163 patients with type 2 (60) and type 3 (103) fractures were retrospectively studied. The mean age was 5.5 years (0.02 to 13.7 y) and weight was 21.6 kg (2.0 to 71.9 kg). Mean fluoroscopy time was 74.1 seconds (10.2 to 288.9 s), and absorbed skin dose at the elbow was 0.53 mGy (0.07 to 2.07 mGy).There were no statistically significant differences between the cohorts. CONCLUSIONS: The smaller prospective cohort had fluoroscopy times and radiation doses that were not statistically different from the larger retrospective cohort, suggesting that the dosimeter measurements are representative of intraoperative radiation exposure during fixation of pediatric SCH fractures. The equivalent dose to the thyroid and gonads was minimal and approximates daily background radiation. Shielding of radiosensitive organs is appropriate when practical to minimize cumulative lifetime radiation exposure, particularly in smaller patients and when longer fluoroscopy times are anticipated. LEVEL OF EVIDENCE: Level 2.


Subject(s)
Fluoroscopy/methods , Fracture Fixation , Humeral Fractures/surgery , Radiation Exposure/prevention & control , Child , Child, Preschool , Female , Fracture Fixation/adverse effects , Fracture Fixation/methods , Fracture Fixation/statistics & numerical data , Humans , Male , Occupational Exposure/adverse effects , Prospective Studies , Protective Devices , Quality Improvement , Radiation Dosage , United States
17.
Am J Emerg Med ; 36(5): 769-773, 2018 May.
Article in English | MEDLINE | ID: mdl-29137905

ABSTRACT

BACKGROUND: Acute asthma exacerbations (AAE) account for many Pediatric Emergency Department (PED) visits. Chest radiography (CXR) is often performed in these patients to identify practice-changing findings such as pneumonia (PNA). Limited knowledge exists to balance the cost and radiation dose of CXR with expected yield of clinically meaningful information. OBJECTIVE: To determine in children with AAE with CXR, whether patient characteristics are associated with radiographic PNA; and significant practice change by initiation of antibiotic. DESIGN/METHODS: Retrospective chart review of AAE patients with CXR performed in a PED in 2014. We examined univariate associations between patient characteristics and PNA on CXR and administration of antibiotic. Multiple logistic regression models then subsequently examined adjusted associations between patient characteristics and both outcomes. RESULTS: Of 288 patients, 43 (15%) had PNA on CXR and 51 (17.8%) received antibiotics. There were no statistically significant univariate associations between either outcome and age, race, gender, insurance status, mode of PED arrival, fever or hypoxia (all p>0.11). Crackles were associated with antibiotic administration (p=0.03), but not PNA on CXR (p=0.07). Only previous antibiotic use within 7days had both significant univariate associations (p=0.002) and adjusted associations with both PNA on CXR (aOR 3.6) and antibiotic administration (aOR 3.3). CONCLUSION: CXR infrequently adds valuable information in children with AAE. Patients treated with antibiotic within 7days are more likely to have PNA identified on CXR and receive antibiotics. A larger study is needed to examine potential significance of hypoxia and crackles.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Asthma/diagnostic imaging , Emergency Service, Hospital , Pneumonia/diagnostic imaging , Radiography, Thoracic/methods , Adolescent , Asthma/complications , Child , Child, Preschool , Disease Progression , Female , Humans , Male , Pneumonia/drug therapy , Practice Guidelines as Topic , Radiation Dosage , Retrospective Studies
18.
Pediatr Radiol ; 47(13): 1745-1750, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28831577

ABSTRACT

BACKGROUND: Human metapneumovirus (HMPV) was identified in 2001 and is a common cause of acute respiratory illness in young children. The radiologic characteristics of laboratory-confirmed HMPV acute respiratory illness in young children have not been systematically assessed. OBJECTIVE: We systematically evaluated the radiographic characteristics of acute respiratory illness associated with HMPV in a prospective cohort of pediatric patients. MATERIALS AND METHODS: We included chest radiographs from children <5 years old with acute respiratory illness who were enrolled in the prospective New Vaccine Surveillance Network (NVSN) study from 2003 to 2009 and were diagnosed with HMPV by reverse transcription-polymerase chain reaction (RT-PCR). Of 215 HMPV-positive subjects enrolled at our tertiary care children's hospital, 68 had chest radiographs obtained by the treating clinician that were available for review. Two fellowship-trained pediatric radiologists, independently and then in consensus, retrospectively evaluated these chest radiographs for their radiographic features. RESULTS: Parahilar opacities were the most commonly observed abnormality, occurring in 87% of children with HMPV. Hyperinflation also occurred frequently (69%). Atelectasis (40%) and consolidation (18%) appeared less frequently. Pleural effusion and pneumothorax were not seen on any radiographs. CONCLUSION: The clinical presentations of HMPV include bronchiolitis, croup and pneumonia. Dominant chest radiographic abnormalities include parahilar opacities and hyperinflation, with occasional consolidation. Recognition of the imaging patterns seen with common viral illnesses like respiratory syncytial virus (RSV) and HMPV might facilitate diagnosis and limit unnecessary antibiotic treatment.


Subject(s)
Metapneumovirus , Paramyxoviridae Infections/diagnostic imaging , Radiography, Thoracic , Respiratory Tract Infections/diagnostic imaging , Respiratory Tract Infections/virology , Acute Disease , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Prospective Studies
19.
PLoS One ; 11(7): e0158825, 2016.
Article in English | MEDLINE | ID: mdl-27391588

ABSTRACT

AIMS: This study harnessed the electronic medical record to assess pancreas volume in patients with type 1 diabetes (T1D) and matched controls to determine whether pancreas volume is altered in T1D and identify covariates that influence pancreas volume. METHODS: This study included 25 patients with T1D and 25 age-, sex-, and weight-matched controls from the Vanderbilt University Medical Center enterprise data warehouse. Measurements of pancreas volume were made from medical imaging studies using magnetic resonance imaging (MRI) or computed tomography (CT). RESULTS: Patients with T1D had a pancreas volume 47% smaller than matched controls (41.16 ml vs. 77.77 ml, P < 0.0001) as well as pancreas volume normalized by subject body weight, body mass index, or body surface area (all P < 0.0001). Pancreatic volume was smaller with a longer duration of T1D across the patient population (N = 25, P = 0.04). Additionally, four individual patients receiving multiple imaging scans displayed progressive declines in pancreas volume over time (~ 6% of volume/year), whereas five controls scanned a year apart did not exhibit a decline in pancreas size (P = 0.03). The pancreas was uniformly smaller on the right and left side of the abdomen. CONCLUSIONS: Pancreas volume declines with disease duration in patients with T1D, suggesting a protracted pathological process that may include the exocrine pancreas.


Subject(s)
Diabetes Mellitus, Type 1/diagnostic imaging , Magnetic Resonance Imaging , Medical Records Systems, Computerized , Organ Size , Pancreas, Exocrine/diagnostic imaging , Tomography, X-Ray Computed , Adult , Female , Humans , Male , Young Adult
20.
J Am Coll Radiol ; 13(3): 320-5, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26482815

ABSTRACT

PURPOSE: Traditionally, the pediatric radiology elective for medical students and pediatric residents constituted a morning teaching session focused mainly on radiography and fluoroscopy. A more structured elective was desired to broaden the exposure to more imaging modalities, create a more uniform educational experience, and include assessment tools. METHODS: In 2012, an introductory e-mail and formal syllabus, including required reading assignments, were sent to participants before the start date. A rotating weekly schedule was expanded to include cross-sectional imaging (ultrasound, CT, MR) and nuclear medicine. The schedule could accommodate specific goals of the pediatric resident or medical student, as requested. Starting in 2013, an online pre-test and post-test were developed, as well as an online end-of-rotation survey specific to the pediatric radiology elective. Taking the Image Gently pledge was required. A scavenger hunt tool, cue cards, and electronic modules were added. RESULTS: Pre-test and post-test scores, averaged over 2 years, showed improvement in radiology knowledge, with scores increasing by 27% for medical students and 21% for pediatric residents. Surveys at the end of the elective were overwhelmingly positive, with constructive criticism and complimentary comments. CONCLUSIONS: We have successfully created an elective experience in radiology that dedicates time to education while preserving the workflow of radiologists. We have developed tools to provide a customized experience with many self-directed learning opportunities. Our tools and techniques are easily translatable to a general or adult radiology elective.


Subject(s)
Curriculum , Diagnostic Imaging , Education, Medical/organization & administration , Models, Organizational , Radiology/education , Teaching/organization & administration , Educational Measurement/methods , Models, Educational , Tennessee
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