Thyroid nodules are common; up to 67% of adults will show nodules on high-quality ultrasound, and 95% of these nodules are benign. FNA cytology is a crucial step in determining the risk of ...malignancy, and a false negative diagnosis at this stage delays cancer treatment. The purpose of this study is to develop a predictive model using machine learning which can identify false negative FNA results based on less-invasive clinical data.
We conducted a retrospective medical record review at one academic and one community center. Inclusion criteria were thyroid nodules evaluated by ultrasound and FNA with a Bethesda II (benign) result or malignancy detected on pathology or FNA. Linear, non–linear, and ensemble models were generated with scikit-learn using 10-fold cross validation with repetition and compared with AUROC. The classification task was the prediction of malignancy using information acquired from less-invasive ultrasound and FNA.
A total of 604 subjects met inclusion criteria; 38 were diagnosed with malignancy. Of all algorithms tested, a Random Forest method achieved the best AUROC (0.64) in separating benign and malignant nodules, though the improvement over other tested algorithms was not statistically significant.
A Random Forest model performed better than random chance using readily available data obtained via standard evaluation of thyroid nodules. The diagnostic probability threshold of this model can be varied to minimize false positives at the cost of increasing the number of false negatives. Future studies will prospectively evaluate the model's performance.
Up to 30% of thyroid nodules are classified as indeterminate after fine needle aspiration biopsy. These indeterminate thyroid nodules (ITNs) require surgical pathology for definitive diagnosis. ...Molecular testing provides additional pre-operative cancer risk stratification but adds expense and invasive testing. The purpose of this study is to utilize a machine learning (ML) algorithm to predict malignancy of ITNs using data available from less invasive tests.
We conducted a retrospective study using medical records from one academic and one community center. Thyroid nodules with an indeterminate diagnosis on fine needle aspiration biopsy and completed diagnostic pathology were included. Linear, non–linear, and non–linear-ensemble ML methods were tested for accuracy when predicting malignancy using 10-fold cross-validation. Classifiers were evaluated using area under the receiver operating characteristics curve (AUROC).
A total of 355 nodules met inclusion criteria. Of these, 171 (48.2%) were diagnosed with cancer. A Random Forest classifier performed the best, producing an accuracy of 79.1%, a sensitivity of 75.5%, specificity of 82.4%, positive predicative value of 80.3%, negative predictive value of 79.0%, and an AUROC of 0.859.
ML methods accurately risk stratify ITNs using data gathered from existing, non–invasive, and inexpensive diagnostic tests. Applying an ML model with existing data can become a cost-effective alternative to molecular testing. Future studies will prospectively evaluate the performance of this ML approach when combined with expert judgment.
A 300 μm thick thin p-on-n silicon sensor was connected to an energy sensitive pixel readout ASIC and exposed to a beam of highly energetic charged particles. By exploiting the spectral information ...and the fine segmentation of the detector, we were able to measure the evolution of the transverse profile of the charge carriers cloud in the sensor as a function of the drift distance from the point of generation. The result does not rely on model assumptions or electric field calculations. The data are also used to validate numerical simulations and to predict the detector spectral response to an X-ray fluorescence spectrum for applications in X-ray imaging.
The Medipix device is a silicon pixelated detector designed by CERN for the detection of different types of radiation. The detector response features can be exploited to identify different types of ...particles: heavy charged particles, mips, electrons or photons. However, while heavily ionizing charged particles are clearly recognizable, electrons and photons can hardly be distinguished from each other and thus, mistagging of radiation quanta has to be considered. Experiments were performed to quantify the mistag rate in different experimental situations. A GEANT4 simulation of the detector and the experimental setup was used to further understand the results. The detection efficiency for photons was studied and the advantages of using a Timepix device highlighted.
Hypothesis: We hypothesized that players in the National Basketball Association (NBA) who sustained a shoulder destabilizing injury could return to play (RTP) successfully at a high rate regardless ...of treatment type.
We used publicly available data to identify and evaluate 50 players who sustained an in-season shoulder instability event (subluxation/dislocation) while playing in the NBA. Demographic variables, return to NBA gameplay, incidence of surgery, time to RTP, recurrent instability events, and player efficiency rating (PER) were collected. Overall RTP was determined, and players were compared by type of injury and mode of treatment.
All players (50/50) returned to game play after sustaining a shoulder instability event. In those treated nonoperatively, athletes who sustained shoulder subluxations returned after an average of 3.6 weeks, compared with 7.6 weeks in those who sustained a shoulder dislocation (P = .037). Players who underwent operative management returned after an average of 19 weeks. Athletes treated operatively were found to have a longer time interval between a recurrent instability event (70 weeks vs. 28.5 weeks, P = .001).
We found 100% rate of RTP after a shoulder instability event in an NBA athlete. Players who experience shoulder dislocations were found to miss more time before RTP and were more likely to undergo surgical intervention compared with those who experienced a subluxation. Surgical repair maintained a longer interval between recurrent instability. Future investigations should aim to evaluate outcomes based on surgical procedures and identify possible risk factors predictive of recurrent instability or failure to RTP.
Arthrodesis of an osteoarthritic second metatarsophalangeal (MTP) joint is suboptimal because of altered gait mechanics; hence, joint-preserving procedures are of value. Autograft interpositional ...arthroplasty is one available option with excellent results, but there are potential concerns regarding donor site morbidity and insufficiency of the autograft material. We present here an alternative technique, an interpositional arthroplasty using allograft. Our technique includes a dorsal incision and joint exposure, removal of cartilage from the metatarsal head, and interposition of human decellularized dermal allograft sutured to the metatarsal head. Allograft interpositional arthroplasty is a feasible technique and can be further investigated as an alternative procedure for patients with second MTP osteoarthritis.
Level of Evidence:
Level V, expert opinion.
In this paper, we describe some of the computational challenges that need to be addressed when developing active Space Radiation Monitors and Dosimeters using the Timepix detectors developed by the ...Medipix2 Collaboration at CERN. Measurement of the Linear Energy Transfer (LET), the source and velocity of incident ionizing radiation, are of initial interest when developing such operational devices because they provide the capability to calculate the Dose-equivalent, and to characterize the radiation field for the design of radiation protective devices. In order to facilitate the LET measurement, we first propose a new method for calculating azimuth direction and polar angle of individual tracks of penetrating charged particles based on the pixel clusters they produce. We then describe an energy compensation method for heavy ion tracks suffering from saturation and plasma effects. Finally, we identify interactions within the detector that need to be excluded from the total effective Dose-Equivalent assessment. We make use of data taken at the HIMAC (Heavy Ion Medical Accelerator Center) facility in Chiba, Japan and NSRL (NASA Space Radiation Laboratory) at the Brookhaven National Laboratory in New York, USA for evaluation purposes.
Category:
Other
Introduction/Purpose:
Patients are often made weight-bearing as tolerated (WBAT) in a controlled ankle motion (CAM) boot for the management of various foot and ankle conditions. The ...CAM boot causes a leg-length discrepancy (LLD) between the booted (longer) and contralateral (shorter) lower extremities. This discrepancy can potentially cause balance problems, undue strain on joints, and discomfort in patients. We hypothesized that a leg-length evening orthotic placed on the plantar aspect of the contralateral shoe improves balance among patients who are WBAT in a CAM boot.
Methods:
Patients made WBAT in a CAM boot were randomized to either the leg-length-evening orthotic intervention group or to a control group in which patients wore a normal shoe of their choice. Patients were followed for two weeks and asked a series of questions pertaining to balance and pain experienced at their knees, hips, and back. Balance was the primary outcome and was scored from 0 (no difficulty with balance) to 10 (great difficulty with balance).
Results:
Out of 107 subjects enrolled and randomized, 95 (88.8%) completed the study, satisfying the a priori sample size requirement of 94 patients. There were no differences in baseline characteristics between groups (p>0.05 for each). Intervention patients reported less difficulty with balance than control patients (intention-to-treat analysis: 2.0+-1.5 versus 3.2+-1.8, p=0.001; as-treated analysis: 2.1+-1.7 versus 3.0+-1.7, p=0.009). Intervention and control patients did not differ with respect to pain experienced at their knees, hips, or back, or in a composite total pain score (p>0.05 for each).
Conclusion:
This multicenter randomized controlled trial found that adding a limb-length-evening orthotic to the plantar aspect of the contralateral shoe in a patient that is WBAT in a CAM boot improves balance. The trial was powered to identify a difference in the primary outcome measure of balance and may have been insufficiently powered to identify differences in knee, hip, back, or total pain.
Background:
Patients are often made weightbearing as tolerated (WBAT) in a controlled ankle motion (CAM) boot for the management of various foot and ankle conditions. The CAM boot causes a leg length ...discrepancy (LLD) between the booted (longer) and contralateral (shorter) lower extremities. This discrepancy can potentially cause balance problems, undue strain on joints, and discomfort in patients. We hypothesized that a leg length–evening orthotic placed on the plantar aspect of the contralateral shoe improves balance among patients who are WBAT in a CAM boot.
Methods:
Patients made WBAT in a CAM boot were randomized to either the leg length–evening orthotic intervention group or to a control group in which patients wore a normal shoe of their choice. Patients were followed for 2 weeks and asked a series of questions pertaining to balance and pain experienced at their knees, hips, and back. Balance was the primary outcome and was scored from 0 (no difficulty with balance) to 10 (great difficulty with balance). Of 107 subjects enrolled and randomized, 95 (88.8%) completed the study, satisfying the a priori sample size requirement of 94 patients. There were no differences in baseline characteristics between groups (P > .05 for each).
Results:
Intervention patients reported less difficulty with balance than control patients (intention-to-treat analysis: 2.0±1.5 vs 3.2±1.8, P = .001; as-treated analysis: 2.1±1.7 vs 3.0±1.7, P = .009). Intervention and control patients did not differ with respect to pain experienced at their knees, hips, or back, or in a composite total pain score (P > .05 for each).
Conclusion:
This multicenter randomized controlled trial found that adding a limb length–evening orthotic to the plantar aspect of the contralateral shoe in a patient that is WBAT in a CAM boot improved patient-reported self-assessment of balance. The trial was powered to identify a difference in the primary outcome measure of balance and may have been insufficiently powered to identify differences in knee, hip, back, or total pain.
Level of Evidence:
Level II, prospective comparative study.
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