Crowd-Sourced Deep Learning for Intracranial Hemorrhage Identification: Wisdom of Crowds or Laissez-Faire.

BACKGROUND AND PURPOSE: Researchers and clinical radiology practices are increasingly faced with the task of selecting the most accurate artificial intelligence tools from an ever-expanding range. In this study, we sought to test the utility of ensemble learning for determining the best combination from 70 models trained to identify intracranial hemorrhage. Furthermore, we investigated whether ensemble deployment is preferred to use of the single best model. It was hypothesized that any individual model in the ensemble would be outperformed by the ensemble. MATERIALS AND METHODS: In this retrospective study, de-identified clinical head CT scans from 134 patients were included. Every section was annotated with "no-intracranial hemorrhage" or "intracranial hemorrhage," and 70 convolutional neural networks were used for their identification. Four ensemble learning methods were researched, and their accuracies as well as receiver operating characteristic curves and the corresponding areas under the curve were compared with those of individual convolutional neural networks. The areas under the curve were compared for a statistical difference using a generalized U-statistic. RESULTS: The individual convolutional neural networks had an average test accuracy of 67.8% (range, 59.4%-76.0%). Three ensemble learning methods outperformed this average test accuracy, but only one achieved an accuracy above the 95th percentile of the individual convolutional neural network accuracy distribution. Only 1 ensemble learning method achieved a similar area under the curve as the single best convolutional neural network (Δarea under the curve = 0.03; 95% CI, -0.01-0.06; P = .17). CONCLUSIONS: None of the ensemble learning methods outperformed the accuracy of the single best convolutional neural network, at least in the context of intracranial hemorrhage detection.

Personalized biomechanical tongue models based on diffusion-weighted MRI and validated using optical tracking of range of motion.

For advanced tongue cancer, the choice between surgery and organ-sparing treatment is often dependent on the expected loss of tongue functionality after treatment. Biomechanical models might assist in this choice by simulating the post-treatment function loss. However, this function loss varies between patients and should, therefore, be predicted for each patient individually. In the present study, the goal was to better predict the postoperative range of motion (ROM) of the tongue by personalizing biomechanical models using diffusion-weighted MRI and constrained spherical deconvolution reconstructions of tongue muscle architecture. Diffusion-weighted MRI scans of ten healthy volunteers were obtained to reconstruct their tongue musculature, which were subsequently registered to a previously described population average or atlas. Using the displacement fields obtained from the registration, the segmented muscle fiber tracks from the atlas were morphed back to create personalized muscle fiber tracks. Finite element models were created from the fiber tracks of the atlas and those of the individual tongues. Via inverse simulation of a protruding, downward, left and right movement, the ROM of the tongue was predicted. This prediction was compared to the ROM measured with a 3D camera. It was demonstrated that biomechanical models with personalized muscles bundles are better in approaching the measured ROM than a generic model. However, to achieve this result a correction factor was needed to compensate for the small magnitude of motion of the model. Future versions of these models may have the potential to improve the estimation of function loss after treatment for advanced tongue cancer.

In-vivo tongue stiffness measured by aspiration: Resting vs general anesthesia.

Tongue cancer treatment often results in impaired speech, swallowing, or mastication. Simulating the effect of treatments can help the patient and the treating physician to understand the effects and impact of the intervention. To simulate deformations of the tongue, identifying accurate mechanical properties of tissue is essential. However, not many succeeded in characterizing in-vivo tongue stiffness. Those who did, measured the tongue At Rest (AR), in which muscle tone subsides even if muscles are not willingly activated. We expected to find an absolute rest state in participants 'under General Anesthesia' (GA). We elaborated on previous work by measuring the mechanical behavior of the in-vivo tongue under aspiration using an improved volume-based method. Using this technique, 5 to 7 measurements were performed on 10 participants both AR and under GA. The obtained Pressure-Shape curves were first analyzed using the initial slope and its variations. Hereafter, an inverse Finite Element Analysis (FEA) was applied to identify the mechanical parameters using the Yeoh, Gent, and Ogden hyperelastic models. The measurements AR provided a mean Young's Modulus of 1638 Pa (min 1035 - max 2019) using the Yeoh constitutive model, which is in line with previous ex-vivo measurements. However, while hoping to find a rest state under GA, the tongue unexpectedly appeared to be approximately 2 to 2.5 times stiffer under GA than AR. Explanations for this were sought by examining drugs administered during GA, blood flow, perfusion, and upper airway reflexes, but neither of these explanations could be confirmed.

Utilization of a 3D printed dental splint for registration during electromagnetically navigated mandibular surgery.

PURPOSE: A dental splint was developed for non-invasive rigid point-based registration in electromagnetically (EM) navigated mandibular surgery. Navigational accuracies of the dental splint were compared with the common approach, that is, using screws as landmarks. METHODS: A dental splint that includes reference registration notches was 3D printed. Different sets of three points were used for rigid point-based registration on a mandibular phantom: notches on the dental splint only, screws on the mandible, contralateral screws (the side of the mandible where the sensor is not fixated) and a combination of screws on the mandible and notches on the dental splint. The accuracy of each registration method was calculated using 45 notches at one side of the mandible and expressed as the target registration error (TRE). RESULTS: Average TREs of 0.83 mm (range 0.7-1.39 mm), 1.28 mm (1.03-1.7 mm), 2.62 mm (1.91-4.0 mm), and 1.34 mm (1.30-1.39 mm) were found, respectively, for point-based registration based on the splint only, screws on the mandible, screws on the contralateral side only, and screws combined with the splint. CONCLUSION: For dentate patients, rigid point-based registration performs best utilizing a dental splint with notches. The dental splint is easy to implement in the surgical, and navigational, workflow, and the notches can be pinpointed and designated on the CT scan with high accuracy. For edentate patients, screws can be used for rigid point-based registration. However, a new design of the screws is recommended to improve the accuracy of designation on the CT scan.

Compulsory treatment in patients' homes in the Netherlands: what do mental health professionals think of this?

BACKGROUND: Compulsory treatment in patients' homes (CTH) will be introduced in the new Dutch mental health legislation. The aim of this study is to identify the opinions of mental health workers in the Netherlands on compulsory community treatment (CCT), and particularly on compulsory treatment in the patients' home. METHODS: This is a mixed methods study, comprising a semi-structured interview and a survey. Forty mental health workers took part in the semi-structured interview about CCT and 20 of them, working in outpatient services, also completed a questionnaire about CTH. Descriptive analyses were performed of indicated (dis) advantages and problems of CCT and of mean scores on the CTH questionnaire. RESULTS: Overall, the mental health workers seemed to have positive opinions on CCT. With respect to CTH, all mean scores were in the middle of the range, possibly indicating that clinicians were uncertain regarding safety issues and potential practical problems accompanying the use of CTH. CONCLUSIONS: The majority of the participating mental health workers in this study had a positive attitude towards CCT, but they seemed relative uncertain about potential possibilities and problems of working with CTH.

Interactive 3D U-net for the segmentation of the pancreas in computed tomography scans.

The increasing incidence of pancreatic cancer will make it the second deadliest cancer in 2030. Imaging based early diagnosis and image guided treatment are emerging potential solutions. Artificial intelligence (AI) can help provide and improve widespread diagnostic expertise and accurate interventional image interpretation. Accurate segmentation of the pancreas is essential to create annotated data sets to train AI, and for computer assisted interventional guidance. Automated deep learning segmentation performance in pancreas computed tomography (CT) imaging is low due to poor grey value contrast and complex anatomy. A good solution seemed a recent interactive deep learning segmentation framework for brain CT that helped strongly improve initial automated segmentation with minimal user input. This method yielded no satisfactory results for pancreas CT, possibly due to a sub-optimal neural network architecture. We hypothesize that a state-of-the-art U-net neural network architecture is better because it can produce a better initial segmentation and is likely to be extended to work in a similar interactive approach. We implemented the existing interactive method, iFCN, and developed an interactive version of U-net method we call iUnet. The iUnet is fully trained to produce the best possible initial segmentation. In interactive mode it is additionally trained on a partial set of layers on user generated scribbles. We compare initial segmentation performance of iFCN and iUnet on a 100CT dataset using dice similarity coefficient analysis. Secondly, we assessed the performance gain in interactive use with three observers on segmentation quality and time. Average automated baseline performance was 78% (iUnet) versus 72% (FCN). Manual and semi-automatic segmentation performance was: 87% in 15 min. for manual, and 86% in 8 min. for iUNet. We conclude that iUnet provides a better baseline than iFCN and can reach expert manual performance significantly faster than manual segmentation in case of pancreas CT. Our novel iUnet architecture is modality and organ agnostic and can be a potential novel solution for semi-automatic medical imaging segmentation in general.

Quantification of tongue mobility impairment using optical tracking in patients after receiving primary surgery or chemoradiation.

PURPOSE: Tongue mobility has shown to be a clinically interesting parameter on functional results after tongue cancer treatment which can be objectified by measuring the Range Of Motion (ROM). Reliable measurements of ROM would enable us to quantify the severity of functional impairments and use these for shared decision making in treatment choices, rehabilitation of speech and swallowing disturbances after treatment. METHOD: Nineteen healthy participants, eighteen post-chemotherapy patients and seventeen post-surgery patients were asked to perform standardized tongue maneuvers in front of a 3D camera system, which were subsequently tracked and corrected for head and jaw motion. Indicators, such as the left-right tongue range and the deflection angle with the horizontal axis were extracted from the tongue trajectory to serve as a quantitative measure for the impaired tongue mobility. RESULTS: The range and deflection angle showed an excellent intra- and interrater reliability (ICC 0.9) The repeatability experiment showed an average standard deviation of 2.5 mm to 3.5 mm for every movement, except the upward movement. The post-surgery patient group showed a smaller tongue range and higher deflection angle overall than the healthy participants. Post-chemoradiation patients showed less difference in tongue ROM compared with healthy participants. Only a few patients showed asymmetrical movement after treatment, which could not always be explained by T-stage or the side of treatment alone. CONCLUSION: We introduced a reliable and reproducible method for measuring the ROM and to quantify for motion impairments, that was able to show differences in tongue ROM between healthy subjects and patients after chemoradiation or surgery. Future research should focus on measuring patients with oral cancer pre- and post-treatment in combination with the collection of detailed information about the individual tongue anatomy, so that the full ROM trajectory can be used to identify changes over time and to quantify functional impairment.

An interactive surgical simulation tool to assess the consequences of a partial glossectomy on a biomechanical model of the tongue.

Oral cancer surgery has a negative influence on the quality of life (QOL). As a result of the complex physiology involved in oral functions, estimation of surgical effects on functionality remains difficult. We present a user-friendly biomechanical simulation of tongue surgery, including closure with suturing and scar formation, followed by an automated adaptation of a finite element (FE) model to the shape of the tongue. Different configurations of our FE model were evaluated and compared to a well-established FE model. We showed that the post-operative impairment as predicted by our model was qualitatively comparable to a patient case for five different tongue maneuvers.

[Euthanasia and physician-assisted suicide for patients with psychiatric illnesses: opinions of residents in psychiatry]. / Euthanasie en hulp bij zelfdoding bij psychiatrische patiënten; wat vinden aiossen psychiatrie?

BACKGROUND: In the Netherlands there is an increasing amount of euthanasia and physician-assisted suicide (eas) for patients with psychiatric illnesses. However, in recent years, psychiatrists have become more reluctant to assist with or apply eas. In 1995, 47% of psychiatrists were prepared to grant a request for eas, compared with 37% in 2016. In the literature various personal, medical and ethical arguments are mentioned for reluctance or willingness regarding eas.
AIM: To determine the point of view of residents in psychiatry about requests for eas, to gain insight into their arguments for being reluctant or willing regarding eas, and to determine their opinion on attention paid to eas during the medical training of a psychiatrist.
METHOD: A survey on eas was developed based on a literature study. Residents in psychiatry from the consortium Zuid-Nederland-Noord (znn) (n=78) were asked to complete this survey online.
RESULTS: A total of 37 residents (47%) responded. Of these, most residents (73%) found it conceivable that they would grant a request for eas from a patient with psychiatric illness. Residents did not agree with the classical arguments for reluctance. The training of psychiatrists paid insufficient structural attention to eas.
CONCLUSION: This study shows that a majority of Dutch residents in psychiatry find it conceivable that they would grant a request for eas. According to these residents, more attention is warranted on eas in the medical training to psychiatrist.

[Physician assistant for the somatic care in the mental health care]. / Physician assistant voor de somatische zorg binnen de ggz.

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Validation of low-cost smartphone-based thermal camera for diabetic foot assessment.

AIMS: Infrared thermal imaging (IR) is not yet routinely implemented for early detection of diabetic foot ulcers (DFU), despite proven clinical effectiveness. Low-cost, smartphone-based IR-cameras are now available and may lower the threshold for implementation, but the quality of these cameras is unknown. We aim to validate a smartphone-based IR-camera against a high-end IR-camera for diabetic foot assessment. METHODS: We acquired plantar IR images of feet of 32 participants with a current or recently healed DFU with the smartphone-based FLIR-One and the high-end FLIR-SC305. Contralateral temperature differences of the entire plantar foot and nine pre-specified regions were compared for validation. Intra-class correlations coefficient (ICC(3,1)) and Bland-Altman plots were used to test agreement. Clinical validity was assessed by calculating statistical measures of diagnostic performance. RESULTS: Almost perfect agreement was found for temperature measurements in both the entire plantar foot and the combined pre-specified regions, respectively, with ICC values of 0.987 and 0.981, Bland-Altman plots' mean Δ = -0.14 and Δ = -0.06. Diagnostic accuracy showed 94% and 93% sensitivity, and 86% and 91% specificity. CONCLUSIONS: The smartphone-based IR-camera shows excellent validity for diabetic foot assessment.

[Compulsory treatment in the community for persons in need of mental health care]. / Gedwongen behandeling van mensen met een psychiatrische stoornis in de thuissituatie.

BACKGROUND: Clinical admissions and inpatient services are increasingly replaced by enhanced community treatment in Western countries. Currently the Dutch mental health legislation is being revised, making compulsory community treatment a novel legal option in The Netherlands. AIM: To summarize the current literature on compulsory community treatment and to review studies relating to efficacy, patients' and carers' perspectives, and costs. METHOD: We conducted a systematic review of the literature, using PubMed and Trip. RESULTS: Current literature does not provide evidence for positive effects of cct in comparison to voluntary care in terms of admission duration, time-to-readmission, and clinical outcomes. CONCLUSION: Results from England and the United States do not provide support for efficacy of cct in terms of number and/or duration of hospital admissions, and in terms of clinical outcomes compared to voluntary treatment. There is a pressing need for studies designed to allow for direct comparisons between outcomes after compulsory hospital admission and compulsory community treatment.

A new method for three-dimensional evaluation of the cranial shape and the automatic identification of craniosynostosis using 3D stereophotogrammetry.

Craniosynostosis is a congenital defect which can result in abnormal cranial morphology. Three dimensional (3D) stereophotogrammetry is potentially an ideal technique for the evaluation of cranial morphology and diagnosis of craniosynostosis because it is fast and harmless. This study presents a new method for objective characterization of the morphological abnormalities of scaphocephaly and trigonocephaly patients using 3D photographs of patients and healthy controls. Sixty 3D photographs of healthy controls in the age range of 3-6 months were superimposed and scaled. Principal component analysis (PCA) was applied to find the mean cranial shape and the cranial shape variation in this normal population. 3D photographs of 20 scaphocephaly and 20 trigonocephaly patients were analysed by this PCA model to test whether cranial deformities of scaphocephaly and trigonocephaly patients could be objectively identified. PCA was used to find the mean cranial shape and the cranial shape variation in the normal population. The PCA model was able to significantly distinguish scaphocephaly and trigonocephaly patients from the normal population. 3D stereophotogrammetry in combination with the presented method can be used to objectively identify and classify the cranial shape of healthy newborns, scaphocephaly and trigonocephaly patients.

[Wernicke encephalopathy and dry beriberi; late complications after bariatric surgery performed on a patient with a psychiatric history]. / Wernicke-encefalopathie en droge beriberi als late complicaties van bariatrische chirurgie bij patiënte met psychiatrisch belast verleden.

A 38-year-old woman was admitted in a psychiatric hospital because of memory disorders. Dry beriberi and Korsakoff's syndrome, as a late neuropsychiatric manifestation of Wernicke's encephalopathy, were established. The beriberi symptoms decreased slowly, but the patient's memory impairments persisted. These clinical features were caused by a thiamine deficiency. Gastric bypass surgery is associated with an increased risk of thiamine deficiency. Excessive alcohol consumption and poor compliance with vitamin deficiency treatment both contributed to the rapid onset of these disorders. The case we describe demonstrates how important it is that patients who have undergone bariatric surgery are prescribed the correct vitamin supplements and that the treatment is continued for an appropriate period of time; this treatment is particularly important in the case of patients who are also suffering from an comorbid alcohol-related disorder.

Construct failure after open reduction and plate fixation of displaced midshaft clavicular fractures.

INTRODUCTION: Worldwide, implants mostly used for fixation of displaced midshaft clavicular fractures (DMCF) are the easily to bend reconstruction plate and the stiffer small fragment locking compression plate. Construct failure rates after plate fixation of DMCF are reported around 5 percent. Possible risk factors for construct failure are implant type and fracture type. However, little is known about the influence of fracture fixation method on construct failure. The aim of this study was to assess construct failure in plate fixation of DMCF and to identify possible risk factors. METHODS: All consecutive patients treated in a level 1 trauma centre with open reduction and fixation of DMCF using a 3.5-mm reconstruction plate or 3.5-mm small fragment locking compression plate between 2007 and 2015 were evaluated. Potential risk factors for construct failure were analysed using univariate analysis. RESULTS: Two hundred and fifty-nine patients were analysed. Fifty DMCF (19%) were fixated with a reconstruction plate and 209 (81%) with a small fragment locking compression plate. Construct failure was seen in 18 patients (6.9%), including 5 broken plates and 13 with screw loosening. Eight percent of all reconstruction plates broke in contrast to 0.5 percent of all small fragment locking compression plates (p=0.001). All broken implants were used as a bridging plate. Loosening of screws was seen in older patients and when the plate was fixated with less than three bicortical screws on one side of the fracture (p=0.002). CONCLUSIONS: Overall construct failure after open reduction and plate fixation of DMCF occurred in 6.9 percent. Risk factors for plate breakage were the use of a reconstruction plate and a bridging method for fracture fixation. Risk factors for screw loosening were an increasing patient age and plate fixation with less than three bicortical screws on one side of the fracture. RECOMMENDATIONS: Based on the results of this study our recommendation is to use a small fragment locking compression plate for open reduction and internal fixation of DMCF. The surgeon should always strive to fixate the plate on both sides of the fracture with at least three bicortical screws.

[Management of blunt renal trauma in paediatric patients]. / Behandeling van stomp nierletsel bij kinderen.

- In 90% of children, blunt abdominal trauma is the cause of renal, splenic or hepatic injury or an injury affecting a combination of these organs.- Because children's kidneys are anatomically less protected than those of adults, potential renal injury following direct trauma affecting the child's flank, for example by a handlebar or knee should be considered.- Symptoms of renal trauma include excoriations or haematoma on the flank, a 'seatbelt-sign', macroscopic haematuria and fractures of the ribs and vertebra.- As haematuria does not correlate with the severity of renal injury, all children with persistent haematuria should undergo renal imaging.- Children without abnormalities on Doppler ultrasound examination and without macroscopic haematuria can be discharged from the emergency room.- Conservative management of blunt renal trauma is indicated for all haemodynamically stable children. However, haemodynamically unstable children need to undergo an urgent laparotomy. The routine use of bed rest is only indicated for grade V renal injuries.- A DMSA scan is recommended 6-12 weeks after trauma for grade IV-V renal injury.

Feasibility of automated target centralization in colonoscopy.

PURPOSE: Early detection of colorectal cancer is key to full recovery. This urged governments to start population screening programs for colorectal cancer, often using flexible endoscopes. Flexible endoscopy is difficult to learn and time-consuming. Automation of flexible endoscopes may increase the capacity for the screening programs. The goal of this pilot study is to investigate the clinical and technical feasibility of an assisting automated navigation algorithm for a colonoscopy procedure. METHODS: Automated navigation (lumen centralization) was implemented in a robotized system designed for conventional flexible endoscopes. Ten novice and eight expert users were asked to perform a diagnostic colonoscopy on a colon model twice: once using the conventional and once using the robotic system. Feasibility was evaluated using time and location data as measures of the system's added value. RESULTS: Automated target centralization (ATC) was turned on by the novices for a median of 4.2% of the time during insertion and 0.3% during retraction. Experts turned ATC on for 4.0% of the time during insertion and 11.6% during retraction. Novices and experts showed comparable times to reach the cecum with the conventional or the robotic setup with ATC. CONCLUSION: The ATC algorithm combined with the robotized endoscope setup works in an experimental setup that closely resembles the clinical environment and is considered feasible, although ATC use was lower than expected. For novices, it was unclear whether the low usage was due to unfamiliarity with the system or because they did not need ATC. Experts used ATC also during the retraction phase of the procedure. This was an unexpected finding and may indicate an added value of the system.

Technical errors and complications in orthopaedic trauma surgery.

INTRODUCTION: Adverse events and associated morbidity and subsequent costs receive increasing attention in clinical practice and research. As opposed to complications, errors are not described or analysed in literature on fracture surgery. The aim of this study was to provide a description of errors and complications in relation to fracture surgery, as well as the circumstances in which they occur, for example urgency, type of surgeon, and type of fracture. METHODS: All errors and complications were recorded prospectively in our hospital's complication registry, which forms an integral part of the electronic medical patient file. All recorded errors and complications in the complication registry linked to fracture surgery between 1 January, 2000 and 31 December, 2010 were analysed. RESULTS: During the study period 4310 osteosynthesis procedures were performed. In 78 (1.8 %) procedures an error in osteosynthesis was registered. The number of procedures in which an error occurred was significantly lower (OR = 0.53; p = 0.007) when an orthopaedic trauma surgeon was part of the operating team. Of all 3758 patients who were admitted to the surgical ward for osteosynthesis, 745 (19.8 %) had one or more postoperative complications registered. There was no significant difference in the number of postoperative complications after osteosynthesis procedures in which an orthopaedic trauma surgeon was present or absent (16.7 vs. 19.1 %; p = 0.088; OR 0.85). DISCUSSION: In the present study the true error rate after osteosynthesis may have been higher than the rate found. Errors that had no significant consequence may be especially susceptible to underreporting. CONCLUSION: The present study suggests that an osteosynthesis procedure performed by or actively assisted by an orthopaedic trauma surgeon decreases the probability of an error in osteosynthesis. Apart from errors in osteosynthesis, the involvement of an orthopaedic trauma surgeon did not lead to a significant reduction in the number of postoperative complications.

[Mechanisms of catatonia]. / Mechanismen van katatonie.

BACKGROUND: Catatonia is being increasingly viewed as a unique syndrome consisting of specific motor signs that respond characteristically and uniformly to benzodiazepines and electroconvulsive therapy. This interpretation is also reflected in changes in the classification of catatonia in DSM-5. An all-embracing pathogenesis of catatonia remains elusive. AIM: To review the mechanisms of catatonia. METHOD: We reviewed the literature. RESULTS: Certain aspects of catatonia can be explained by a number of different mechanisms. We present a new, more comprehensive model involving the vagal nerve. CONCLUSION: Further research into the underlying mechanisms of catatonia is needed in order to to find new therapies.

Make it spin: individual trapping of sperm for analysis and recovery using micro-contact printing.

In this article, we describe the development of a high throughput platform to spatially manipulate viable sperm for motility measurements and recovery of the best single sperm for fertilization purposes. Micro-contact printing was used to pattern islands of adhesive proteins (fibronectin) separated by sperm repellent species (Pluronic acid F-127) on commercially available polystyrene substrates. Following washing, arrays of viable single sperm were captured onto the islands demonstrating for the first time that sperm can be trapped by micro-contact printing with patterning efficiency of 90% while retaining 100% viability. These were then subjected to motility analysis whilst remaining spatially confined to the islands. Single sperm motility was assessed (n = 37) by software analysis measuring the number of rotations per second (degrees s⁻¹). The assignment of array coordinates allows the more active single sperm to be easily identified and recovered by a simple micromanipulator pipette aspiration step with automated possibility for assisted reproductive technologies or further quality correlation analysis. Taken together, we show for the first time a technique to simultaneously screen thousands of viable single sperm for motility assessment while retaining the ability for single species recovery for enhanced fertilization purposes.