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1.
Bayesian Anal ; 19(2): 623-647, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39183822

RESUMEN

Current protocols to estimate the number, size, and location of cancerous lesions in the prostate using multiparametric magnetic resonance imaging (mpMRI) are highly dependent on reader experience and expertise. Automatic voxel-wise cancer classifiers do not directly provide estimates of number, location, and size of cancerous lesions that are clinically important. Existing spatial partitioning methods estimate linear or piecewise-linear boundaries separating regions of local stationarity in spatially registered data and are inadequate for the application of lesion detection. Frequentist segmentation and clustering methods often require pre-specification of the number of clusters and do not quantify uncertainty. Previously, we developed a novel Bayesian functional spatial partitioning method to estimate the boundary surrounding a single cancerous lesion using data derived from mpMRI. We propose a Bayesian functional spatial partitioning method for multiple lesion detection with an unknown number of lesions. Our method utilizes functional estimation to model the smooth boundary curves surrounding each cancerous lesion. In a Reversible Jump Markov Chain Monte Carlo (RJ-MCMC) framework, we develop novel jump steps to jointly estimate and quantify uncertainty in the number of lesions, their boundaries, and the spatial parameters in each lesion. Through simulation we show that our method is robust to the shape of the lesions, number of lesions, and region-specific spatial processes. We illustrate our method through the detection of prostate cancer lesions using MRI.

2.
MAGMA ; 37(4): 721-735, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39042205

RESUMEN

OBJECTIVE: Quantitative parameter mapping conventionally relies on curve fitting techniques to estimate parameters from magnetic resonance image series. This study compares conventional curve fitting techniques to methods using neural networks (NN) for measuring T2 in the prostate. MATERIALS AND METHODS: Large physics-based synthetic datasets simulating T2 mapping acquisitions were generated for training NNs and for quantitative performance comparisons. Four combinations of different NN architectures and training corpora were implemented and compared with four different curve fitting strategies. All methods were compared quantitatively using synthetic data with known ground truth, and further compared on in vivo test data, with and without noise augmentation, to evaluate feasibility and noise robustness. RESULTS: In the evaluation on synthetic data, a convolutional neural network (CNN), trained in a supervised fashion using synthetic data generated from naturalistic images, showed the highest overall accuracy and precision amongst the methods. On in vivo data, this best performing method produced low-noise T2 maps and showed the least deterioration with increasing input noise levels. DISCUSSION: This study showed that a CNN, trained with synthetic data in a supervised manner, may provide superior T2 estimation performance compared to conventional curve fitting, especially in low signal-to-noise regions.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Redes Neurales de la Computación , Próstata , Relación Señal-Ruido , Humanos , Masculino , Próstata/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Reproducibilidad de los Resultados
3.
AJR Am J Roentgenol ; 221(6): 788-804, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37377363

RESUMEN

The first commercially available 7-T MRI scanner (Magnetom Terra) was approved by the FDA in 2017 for clinical imaging of the brain and knee. After initial protocol development and sequence optimization efforts in volunteers, the 7-T system, in combination with an FDA-approved 1-channel transmit/32-channel receive array head coil, can now be routinely used for clinical brain MRI examinations. The ultrahigh field strength of 7-T MRI has the advantages of improved spatial resolution, increased SNR, and increased CNR but also introduces an array of new technical challenges. The purpose of this article is to describe an institutional experience with the use of the commercially available 7-T MRI scanner for routine clinical brain imaging. Specific clinical indications for which 7-T MRI may be useful for brain imaging include brain tumor evaluation with possible perfusion imaging and/or spectroscopy, radiotherapy planning; evaluation of multiple sclerosis and other demyelinating diseases, evaluation of Parkinson disease and guidance of deep brain stimulator placement, high-detail intracranial MRA and vessel wall imaging, evaluation of pituitary pathology, and evaluation of epilepsy. Detailed protocols, including sequence parameters, for these various indications are presented, and implementation challenges (including artifacts, safety, and side effects) and potential solutions are explored.


Asunto(s)
Neoplasias Encefálicas , Epilepsia , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Neuroimagen/métodos , Neoplasias Encefálicas/diagnóstico por imagen
4.
J Appl Stat ; 50(3): 805-826, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36819087

RESUMEN

Multi-parametric MRI (mpMRI) is a critical tool in prostate cancer (PCa) diagnosis and management. To further advance the use of mpMRI in patient care, computer aided diagnostic methods are under continuous development for supporting/supplanting standard radiological interpretation. While voxel-wise PCa classification models are the gold standard, few if any approaches have incorporated the inherent structure of the mpMRI data, such as spatial heterogeneity and between-voxel correlation, into PCa classification. We propose a machine learning-based method to fill in this gap. Our method uses an ensemble learning approach to capture regional heterogeneity in the data, where classifiers are developed at multiple resolutions and combined using the super learner algorithm, and further account for between-voxel correlation through a Gaussian kernel smoother. It allows any type of classifier to be the base learner and can be extended to further classify PCa sub-categories. We introduce the algorithms for binary PCa classification, as well as for classifying the ordinal clinical significance of PCa for which a weighted likelihood approach is implemented to improve the detection of less prevalent cancer categories. The proposed method has shown important advantages over conventional modeling and machine learning approaches in simulations and application to our motivating patient data.

5.
NMR Biomed ; 36(5): e4874, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36368912

RESUMEN

The purpose of this work is to propose a tier-based formalism for safety assessment of custom-built radio-frequency (RF) coils that balances validation effort with the effort put in determinating the safety factor. The formalism has three tier levels. Higher tiers require increased effort when validating electromagnetic simulation results but allow for less conservative safety factors. In addition, we propose a new method to calculate modeling uncertainty between simulations and measurements and a new method to propagate uncertainties in the simulation into a safety factor that minimizes the risk of underestimating the peak specific absorption rate (SAR). The new safety assessment procedure was completed for all tier levels for an eight-channel dipole array for prostate imaging at 7 T and an eight-channel dipole array for head imaging at 10.5 T, using data from two different research sites. For the 7 T body array, the validation procedure resulted in a modeling uncertainty of 77% between measured and simulated local SAR distributions. For a situation where RF shimming is performed on the prostate, average power limits of 2.4 and 4.5 W/channel were found for tiers 2 and 3, respectively. When the worst-case peak SAR among all phase settings was calculated, power limits of 1.4 and 2.7 W/channel were found for tiers 2 and 3, respectively. For the 10.5 T head array, a modeling uncertainty of 21% was found based on B1 + mapping. For the tier 2 validation, a power limit of 2.6 W/channel was calculated. The demonstrated tier system provides a strategy for evaluating modeling inaccuracy, allowing for the rapid translation of novel coil designs with conservative safety factors and the implementation of less conservative safety factors for frequently used coil arrays at the expense of increased validation effort.


Asunto(s)
Imagen por Resonancia Magnética , Ondas de Radio , Masculino , Humanos , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Simulación por Computador , Próstata/diagnóstico por imagen
6.
J Orthop Res ; 41(7): 1449-1463, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36484124

RESUMEN

Current clinical MRI of patients with juvenile osteochondritis dissecans (JOCD) is limited by the low reproducibility of lesion instability evaluation and inability to predict which lesions will heal after nonoperative treatment and which will later require surgery. The aim of this study is to verify the ability of apparent diffusion coefficient (ADC) to detect differences in lesion microstructure between different JOCD stages, treatment groups, and healthy, unaffected contralateral knees. Pediatric patients with JOCD received quantitative diffusion MRI between January 2016 and September 2020 in this prospective research study. A disease stage (I-IV) and stability of each JOCD lesion was evaluated. ADCs were calculated in progeny lesion, interface, parent bone, cartilage overlying lesion, control bone, and control cartilage regions. ADC differences were evaluated using linear mixed models with Bonferroni correction. Evaluated were 30 patients (mean age, 13 years; 21 males), with 40 JOCD-affected and 12 healthy knees. Nine patients received surgical treatment after MRI. Negative Spearman rank correlations were found between ADCs and JOCD stage in the progeny lesion (ρ = -0.572; p < 0.001), interface (ρ = -0.324; p = 0.041), and parent bone (ρ = -0.610; p < 0.001), demonstrating the sensitivity of ADC to microstructural differences in lesions at different JOCD stages. We observed a significant increase in the interface ADCs (p = 0.007) between operative (mean [95% CI] = 1.79 [1.56-2.01] × 10-3 mm2 /s) and nonoperative group (1.27 [0.98-1.57] × 10-3 mm2 /s). Quantitative diffusion MRI detects microstructural differences in lesions at different stages of JOCD progression towards healing and reveals differences between patients assigned for operative versus nonoperative treatment.


Asunto(s)
Cartílago Articular , Osteocondritis Disecante , Masculino , Humanos , Niño , Adolescente , Osteocondritis Disecante/diagnóstico por imagen , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Reproducibilidad de los Resultados , Estudios Prospectivos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Imagen de Difusión por Resonancia Magnética
7.
Biometrics ; 79(2): 604-615, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-34806765

RESUMEN

Spatial partitioning methods correct for nonstationarity in spatially related data by partitioning the space into regions of local stationarity. Existing spatial partitioning methods can only estimate linear partitioning boundaries. This is inadequate for detecting an arbitrarily shaped anomalous spatial region within a larger area. We propose a novel Bayesian functional spatial partitioning (BFSP) algorithm, which estimates closed curves that act as partitioning boundaries around anomalous regions of data with a distinct distribution or spatial process. Our method utilizes transitions between a fixed Cartesian and moving polar coordinate system to model the smooth boundary curves using functional estimation tools. Using adaptive Metropolis-Hastings, the BFSP algorithm simultaneously estimates the partitioning boundary and the parameters of the spatial distributions within each region. Through simulation we show that our method is robust to shape of the target zone and region-specific spatial processes. We illustrate our method through the detection of prostate cancer lesions using magnetic resonance imaging.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Teorema de Bayes , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética , Algoritmos , Simulación por Computador
8.
World J Pediatr Surg ; 5(4): e000440, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36474746

RESUMEN

Objective: With few studies investigating the effectiveness of telemedicine (TM) in pediatric otolaryngology (ear, nose, and throat; ENT), its role in clinical practice is unclear. The objective of this study was to investigate provider perspectives regarding utility of TM in pediatric ENT practice. Methods: A survey gauging the relative merits of TM visits for common pediatric ENT chief complaints and postoperative visits was distributed to all pediatric ENT providers at a tertiary care, free-standing children's hospital. Respondents were asked to assess the effectiveness of TM visits compared with in-person visits for completing the following tasks: history collection, physical examination, medical decision-making, and patient counseling. Results: Providers rated TM visits as less useful than in-person visits for completing the most predefined tasks but did identify advantages in history taking via TM for the majority of complaints. Compared with providers with ≥10 years of experience, those with <10 years of experience found TM to be more effective than the in-person appointment for making clinical decisions for patients presenting with recurrent/chronic pharyngitis, neck masses, and stridor/noisy breathing. Opinions regarding the utility of TM for postoperative visits were mixed, with adenoidectomy, tonsillectomy and superficial procedures being most frequently deemed appropriate for TM. Conclusions: The introduction of TM to pediatric ENT faces limitations in detailed examination of areas not accessible without specialized instrumentation. Due to its strength in history taking, results suggest an asynchronous, 'store and forward' encounter followed by an in-person physical examination to confirm the diagnosis and treatment plan could be beneficial.

9.
Magn Reson Med ; 88(6): 2645-2661, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35906923

RESUMEN

PURPOSE: To present electromagnetic simulation setups for detailed analyses of respiration's impact on B 1 + $$ {B}_1^{+} $$ and E-fields, local specific absorption rate (SAR) and associated safety-limits for 7T cardiac imaging. METHODS: Finite-difference time-domain electromagnetic field simulations were performed at five respiratory states using a breathing body model and a 16-element 7T body transceiver RF-coil array. B 1 + $$ {B}_1^{+} $$ and SAR are analyzed for fixed and moving coil configurations. SAR variations are investigated using phase/amplitude shimming considering (i) a local SAR-controlled mode (here SAR calculations consider RF amplitudes and phases) and (ii) a channel-wise power-controlled mode (SAR boundary calculation is independent of the channels' phases, only dependent on the channels' maximum amplitude). RESULTS: Respiration-induced variations of both B 1 + $$ {B}_1^{+} $$ amplitude and phase are observed. The flip angle homogeneity depends on the respiratory state used for B 1 + $$ {B}_1^{+} $$ shimming; best results were achieved for shimming on inhale and exhale simultaneously ( | Δ C V | < 35 % $$ \mid \Delta CV\mid <35\% $$ ). The results reflect that respiration impacts position and amplitude of the local SAR maximum. With the local-SAR-control mode, a safety factor of up to 1.4 is needed to accommodate for respiratory variations while the power control mode appears respiration-robust when the coil moves with respiration (SAR peak decrease: 9% exhale→inhale). Instead, a spatially fixed coil setup yields higher SAR variations with respiration. CONCLUSION: Respiratory motion does not only affect the B 1 + $$ {B}_1^{+} $$ distribution and hence the image contrast, but also location and magnitude of the peak spatial SAR. Therefore, respiration effects may need to be included in safety analyses of RF coils applied to the human thorax.


Asunto(s)
Campos Electromagnéticos , Imagen por Resonancia Magnética , Simulación por Computador , Humanos , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Ondas de Radio
10.
JAMA Netw Open ; 5(5): e229712, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35499827

RESUMEN

Importance: The factors associated with the failure of nonoperative management of appendicitis and the differences in patient-reported outcomes between successful and unsuccessful nonoperative management remain unknown. Objectives: To investigate factors associated with the failure of nonoperative management of appendicitis and compare patient-reported outcomes between patients whose treatment succeeded and those whose treatment failed. Design, Setting, and Participants: This study was a planned subgroup secondary analysis conducted in 10 children's hospitals that included 370 children aged 7 to 17 years with uncomplicated appendicitis enrolled in a prospective, nonrandomized clinical trial between May 1, 2015, and October 31, 2018, with 1-year follow-up comparing nonoperative management with antibiotics vs surgery for uncomplicated appendicitis. Statistical analysis was performed from November 1, 2019, to February 12, 2022. Interventions: Nonoperative management with antibiotics vs surgery. Main Outcomes and Measures: Failure of nonoperative management and patient-reported outcomes. The relative risk (RR) of failure based on sociodemographic and clinical characteristics was calculated. Patient-reported outcomes were compared based on the success or failure of nonoperative management. Results: Of 370 patients (34.6% of 1068 total patients; 229 boys [61.9%]; median age, 12.3 years [IQR, 10.0-14.6 years]) enrolled in the nonoperative group, treatment failure occurred for 125 patients (33.8%) at 1 year, with 53 patients (14.3%) undergoing appendectomy during initial hospitalization and 72 patients (19.5%) experiencing delayed treatment failure after hospital discharge. Higher patient-reported pain at presentation was associated with increased risk of in-hospital treatment failure (RR, 2.1 [95% CI, 1.0-4.4]) but not delayed treatment failure (RR, 1.3 [95% CI, 0.7-2.3]) or overall treatment failure at 1 year (RR, 1.5 [95% CI, 1.0-2.2]). Pain duration greater than 24 hours was associated with decreased risk of delayed treatment failure (RR, 0.3 [95% CI, 0.1-1.0]) but not in-hospital treatment failure (RR, 1.2 [95% CI, 0.5-2.7]) or treatment failure at 1 year (RR, 0.7 [95% CI, 0.4-1.2]). There was no increased risk of treatment failure associated with age, white blood cell count, sex, race, ethnicity, primary language, insurance status, transfer status, symptoms at presentation, or imaging results. Health care satisfaction at 30 days and patient-reported, health-related quality of life at 30 days and 1 year were not different. Satisfaction with the decision was higher with successful nonoperative management at 30 days (28.0 vs 27.0; difference, 1.0 [95% CI, 0.01-2.0]) and 1 year (28.1 vs 27.0; difference, 1.1 [95% CI, 0.2-2.0]). Conclusions and Relevance: This analysis suggests that a higher pain level at presentation was associated with a higher risk of initial failure of nonoperative management and that a longer duration of pain was associated with lower risk of delayed treatment failure. Although satisfaction was high in both groups, satisfaction with the treatment decision was higher among patients with successful nonoperative management at 1 year. Trial Registration: ClinicalTrials.gov Identifier: NCT02271932.


Asunto(s)
Apendicitis , Antibacterianos/uso terapéutico , Apendicitis/complicaciones , Apendicitis/epidemiología , Apendicitis/terapia , Niño , Femenino , Humanos , Masculino , Dolor/tratamiento farmacológico , Estudios Prospectivos , Calidad de Vida
11.
MAGMA ; 35(4): 631-644, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35579785

RESUMEN

Multiparametric MRI of the prostate at clinical magnetic field strengths (1.5/3 Tesla) has emerged as a reliable noninvasive imaging modality for identifying clinically significant cancer, enabling selective sampling of high-risk regions with MRI-targeted biopsies, and enabling minimally invasive focal treatment options. With increased sensitivity and spectral resolution, ultra-high-field (UHF) MRI (≥ 7 Tesla) holds the promise of imaging and spectroscopy of the prostate with unprecedented detail. However, exploiting the advantages of ultra-high magnetic field is challenging due to inhomogeneity of the radiofrequency field and high local specific absorption rates, raising local heating in the body as a safety concern. In this work, we review various coil designs and acquisition strategies to overcome these challenges and demonstrate the potential of UHF MRI in anatomical, functional and metabolic imaging of the prostate and pelvic lymph nodes. When difficulties with power deposition of many refocusing pulses are overcome and the full potential of metabolic spectroscopic imaging is used, UHF MR(S)I may aid in a better understanding of the development and progression of local prostate cancer. Together with large field-of-view and low-flip-angle anatomical 3D imaging, 7 T MRI can be used in its full strength to characterize different tumor stages and help explain the onset and spatial distribution of metastatic spread.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias de la Próstata , Estudios de Factibilidad , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Ondas de Radio
12.
J Surg Res ; 277: 138-147, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35489219

RESUMEN

INTRODUCTION: Telemedicine use within pediatric surgery fields has been growing, but research on the utility of remote evaluation in the perioperative period remains scarce. The objective of this study was to examine the utility of perioperative telemedicine care for the pediatric patient by evaluating the outcomes following completion of an outpatient appointment with a surgical provider. MATERIALS AND METHODS: We performed a retrospective chart review of all patients who completed a telemedicine appointment with a provider across nine pediatric surgery divisions, without a limitation based on patient-specific characteristics or telemedicine platform. We examined the result of the initial telemedicine appointment and the outcome of any surgical procedure that was performed as a result. RESULTS: A total of 803 patients were evaluated by telemedicine during the study period. Of the 164 encounters (20.2%) that were followed by a surgery, nearly 70% were performed using a video. There was no discordance in the preoperative and postoperative diagnoses for more than 98% of patients. Nearly 25% of operations were followed by at least a 1-night hospital stay and 6.7% of patients developed a postoperative complication. CONCLUSIONS: Telemedicine is a safe tool for evaluating pediatric patients in the preoperative and postoperative phases of care and offers potential value for families seeking an alternative to the traditional in-person appointment. Ongoing support will require permanent legislative changes aimed at ensuring comparable compensation and the development of strategies to adapt the outpatient healthcare model to better accommodate the evolving requirements of remotely evaluating and treating pediatric patients.


Asunto(s)
Especialidades Quirúrgicas , Telemedicina , Niño , Humanos , Tiempo de Internación , Cuidados Preoperatorios , Estudios Retrospectivos , Telemedicina/métodos
13.
J Pediatr Surg ; 57(8): 1614-1621, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35430030

RESUMEN

BACKGROUND: There has been increased telemedicine use secondary to the COVID-19 pandemic. The objective of this study was to assess patient/parent satisfaction with their telemedicine experience, gauge provider perspective on telemedicine for the management of pediatric colorectal disease and evaluate the quality of telemedicine care being provided. METHODS: A cross sectional study was performed at a single institution from March 2020-February 2021. Patients who completed a patient/parent telemedicine survey after a telemedicine appointment and nurse practitioners/surgeons who completed a provider telemedicine survey were included. Patient and provider characteristics and responses were analyzed using descriptive statistics. Differences between the levels of provider confidence to provide telemedicine care were analyzed using Pearson's chi-square test. RESULTS: 118 patients/parents completed the survey. The median age of patients was 7 years. Most patients were male (59%) and White (73%). The most common diagnosis was anorectal malformation (49%). 71% of parents felt the telemedicine visit was as effective or better than an in-person visit and over 70% said they prefer a telemedicine visit to an in-person visit. Ten surgeons and 8 nurse practitioners completed the provider survey. 28% had previous telemedicine experience and 94% planned to continue offering telemedicine appointments. Providers felt significantly more confident performing clinical duties via video telemedicine compared to telephone telemedicine. CONCLUSIONS: Telemedicine is a useful adjunct or alternative in pediatric surgery for complex patients who require multidisciplinary care. Providers show confidence with the use of video telemedicine and parents show high satisfaction, with the majority preferring telemedicine visits over in-person visits. LEVEL OF EVIDENCE: IV.


Asunto(s)
COVID-19 , Telemedicina , COVID-19/epidemiología , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Pandemias , Satisfacción del Paciente
14.
Stat Med ; 41(3): 483-499, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-34747059

RESUMEN

Multi-parametric magnetic resonance imaging (mpMRI) has been playing an increasingly important role in the detection of prostate cancer (PCa). Various computer-aided detection algorithms were proposed for automated PCa detection by combining information in multiple mpMRI parameters. However, there are specific features of mpMRI, including between-voxel correlation within each prostate and heterogeneity across patients, that have not been fully explored but could potentially improve PCa detection if leveraged appropriately. This article proposes novel Bayesian approaches for voxel-wise PCa classification that accounts for spatial correlation and between-patient heterogeneity in the mpMRI data. Modeling the spatial correlation is challenging due to the extreme high dimensionality of the data, and we propose three scalable approaches based on Nearest Neighbor Gaussian Process (NNGP), reduced-rank approximation, and a conditional autoregressive (CAR) model that approximates a Gaussian Process with the Matérn covariance, respectively. Our simulation study shows that properly modeling the spatial correlation and between-patient heterogeneity can substantially improve PCa classification. Application to in vivo data illustrates that classification is improved by all three spatial modeling approaches considered, while modeling the between-patient heterogeneity does not further improve our classifiers. Among the proposed models, the NNGP-based model is recommended given its high classification accuracy and computational efficiency.


Asunto(s)
Próstata , Neoplasias de la Próstata , Algoritmos , Teorema de Bayes , Humanos , Imagen por Resonancia Magnética , Masculino , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología
15.
J Pediatr Surg ; 57(1): 80-85, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34686377

RESUMEN

PURPOSE: Due to the COVID-19 pandemic, we transitioned from an in-person bowel management program (BMP) to a telemedicine BMP. The telemedicine BMP consisted of video and/or phone call visits (remote) or a single initial in-person visit followed by remote visits (hybrid). We hypothesized that patient/family satisfaction of a telemedicine BMP would be comparable to an in-person BMP and that there would be improvement in quality of life and functional outcomes after the telemedicine BMP. METHODS: After IRB approval, demographic and outcomes data were obtained for patients who underwent the telemedicine BMP from May-October 2020. Outcomes included a parent/patient satisfaction survey, Pediatric Quality of Life Inventory (PedsQL), and parent/patient-reported outcome measures (Vancouver, Baylor, and Cleveland scores) at baseline, 1 and 3 month follow-up. Variables were compared using Chi-square or Wilcoxon-Mann-Whitney tests and a generalized mixed model was used to evaluate outcomes scores at follow-up compared to baseline. RESULTS: Sixty-seven patients were included in our analysis with an average age of 8.6 years (SD: 3.9). Patients had the following diagnoses anorectal malformation (52.2%), Hirschsprung's disease (20.9%), functional constipation (19.4%), myelomeningocele (6.0%), and spinal injury (1.5%). Forty-eight patients (72%) underwent the remote BMP and 19 (28%) underwent the hybrid BMP. Sixty-two percent of parents completed the satisfaction survey, with a median score of 5 (very satisfied) for all questions. Over 75% of parents said they would prefer a telemedicine program over an in-person program. There was significant improvement in the Baylor and Vancouver scores after the BMP (p < 0.01), but no difference in the PedsQL or Cleveland scores (p > 0.05). There was a significant improvement in stool continence after the BMP (p < 0.01). CONCLUSION: A telemedicine BMP can be an acceptable alternative to a traditional in-person program. There was high parental/patient satisfaction and significant improvement in outcomes. Further research is needed to assess long-term outcomes. LEVEL OF EVIDENCE: III.


Asunto(s)
COVID-19 , Telemedicina , Niño , Humanos , Pandemias , Satisfacción del Paciente , Calidad de Vida , SARS-CoV-2
16.
IEEE Access ; 9: 109214-109223, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34527506

RESUMEN

Multi-zonal segmentation is a critical component of computer-aided diagnostic systems for detecting and staging prostate cancer. Previously, convolutional neural networks such as the U-Net have been used to produce fully automatic multi-zonal prostate segmentation on magnetic resonance images (MRIs) with performance comparable to human experts, but these often require large amounts of manually segmented training data to produce acceptable results. For institutions that have limited amounts of labeled MRI exams, it is not clear how much data is needed to train a segmentation model, and which training strategy should be used to maximize the value of the available data. This work compares how the strategies of transfer learning and aggregated training using publicly available external data can improve segmentation performance on internal, site-specific prostate MR images, and evaluates how the performance varies with the amount of internal data used for training. Cross training experiments were performed to show that differences between internal and external data were impactful. Using a standard U-Net architecture, optimizations were performed to select between 2D and 3D variants, and to determine the depth of fine-tuning required for optimal transfer learning. With the optimized architecture, the performance of transfer learning and aggregated training were compared for a range of 5-40 internal datasets. The results show that both strategies consistently improve performance and produced segmentation results that are comparable to that of human experts with approximately 20 site-specific MRI datasets. These findings can help guide the development of site-specific prostate segmentation models for both clinical and research applications.

17.
J Surg Res ; 267: 605-611, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34271267

RESUMEN

BACKGROUND: Pilonidal disease is common amongst adolescent males and females and often leads to recurrent symptoms and life-altering morbidity. The traditional surgical approach includes wide excision of the involved area and carries a high rate of postoperative morbidity. A minimally invasive surgical approach using trephines was described by Gips in 2008 and has since been widely adopted by many surgeons. The aim of this study was to explore outcomes of the trephination procedure for pediatric and adolescent patients by evaluating postoperative wound healing and disease recurrence. MATERIALS AND METHODS: A retrospective cohort study for patients that underwent the trephination procedure as part of standard of care for the treatment of pilonidal disease from November 1, 2019-November 1, 2020 was performed. Patient demographics, presenting characteristics, and previous treatment history were identified. Outcome measures included healing time, recurrent disease, and need for reoperation. RESULTS: A total of 19 patients underwent the trephination procedure at a mean age of 16.4 years of age. An average of 3.8 pits were excised and there were no reported intraoperative complications. Following trephination, 26.3% of patients were healed at 30-day's, with just over 40% showing complete healing by 6-months. The recurrence rate was 16.1% at 6-months and approximately 15% of patients required a second surgery. CONCLUSION: Early results for trephination at our institution show a high rate of healing complications and frequent reoperation. Future research is needed to establish the role of the trephination procedure in the context of defining the best practices for treating this challenging disease.


Asunto(s)
Seno Pilonidal/cirugía , Trepanación , Adolescente , Niño , Humanos , Complicaciones Posoperatorias , Reoperación/estadística & datos numéricos , Estudios Retrospectivos
18.
BMJ Case Rep ; 14(6)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34167993

RESUMEN

A 72-year-old man presented to clinic with a 1-week history of worsening groin pain. He had a normal hip examination and tenderness worsened with valsalva, but no mass palpated in the inguinal region. He was found to have a large saccular aneurysm of the iliofemoral vein on ultrasound and subsequently started on anticoagulation and referred to vascular surgery.


Asunto(s)
Aneurisma , Hernia Inguinal , Anciano , Aneurisma/diagnóstico por imagen , Ingle/diagnóstico por imagen , Hernia Inguinal/diagnóstico por imagen , Humanos , Masculino , Ultrasonografía , Venas
20.
J Surg Res ; 267: 274-283, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34171563

RESUMEN

BACKGROUND: Prior to the COVID-19 pandemic, the use of telemedicine to evaluate pediatric surgery patients was uncommon. Due in part to restrictions imposed to mitigate the spread of the virus, the use of telemedicine within pediatric surgery has significantly expanded. METHODS: Prior to the use of telemedicine within surgery divisions at our institution, pediatric surgeons were surveyed to determine their perspectives on the use of telemedicine. Following the expanded use of telemedicine in response to the COVID-19 pandemic, a follow up survey was distributed to determine the impact of telemedicine and the perceived benefits and barriers of continuing its use going forward. RESULTS: The pre-COVID survey was completed by 37 surgeons and the post-COVID survey by 36 surgeons and advanced practice providers across 10 pediatric surgical divisions. General surgeons were the most represented division for both the pre- (25%) and post-COVID (33.3%) survey. Less than 25% of providers reported use of telemedicine at any point in their career prior to COVID-19; but following the expanded use of telemedicine 95% of respondents reported interest in continuing its use. After expansion, 25% of respondents were concerned with the possibility of inaccurate diagnoses when using telemedicine compared to nearly 50% prior to expanded use. CONCLUSION: Following the expanded use of telemedicine within pediatric surgery, there was a decrease in the concern for inaccurate diagnoses and a near uniform desire to continue its use. Going forward, it will be imperative for pediatric surgeons to take an active role in creating a process for implementing telemedicine that best fits their needs and the needs of their patients and patients' families.


Asunto(s)
COVID-19 , Pediatría , Cirujanos , Telemedicina , Niño , Humanos , Pandemias , Encuestas y Cuestionarios , Telemedicina/tendencias
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