P07.02.B Neuro-oncological augmented reality planning (NOA-p)

Background

When preparing for the resection of an intracranial lesion, neuronavigation with a tracked pointer is most often used to determine lesion borders and the optimal approach. This can sometimes prove challenging, especially for deep-seated lesions. Augmented Reality (AR), directly displaying the lesion on the patient’s skin, can simplify and improve this step.

Material and Methods

We developed a system for inside-out infrared tracking that does not require an external tracking camera or external computer and allows for heads-up displaying an AR scene on the Microsoft HoloLens II. Twenty patients planned for the resection of an intracerebral lesion were included in our study. After patient registration, the lesion outlines were marked on the patient’s skin by different participants, consecutively using the Brainlab neuronavigation system and the HoloLens. Each registration on both systems provided a registration transform that was compared for accuracy and consistency. The performance of the participants was measured in terms of duration and accuracy and compared to expert registration and delineation.

Results

Both registration and delineation were significantly faster with AR (p=0.02 and p<0.001, respectively, and p<0.001 for the total duration), taking 79.23±17.48 and 39.58±39.10 seconds while neuronavigation required 96.61±24.54 and 90.80±44.09 seconds. AR had a registration offset of 3.3mm and 3.4°, and was more consistent compared to neuronavigation. AR facilitated more accurate and detailed lesion delineation, while neuronavigation often overestimated lesion size.

Conclusion

Augmented reality provides a faster and more accurate alternative for resection planning. Lesion delineation is more intuitive while remaining high in accuracy. Future research should focus on further intraoperative implementations.

Fatigue and the prediction of negative health outcomes: A systematic review with meta-analysis

INTRODUCTION

Fatigue is a common complaint among older adults. Evidence grows that fatigue is linked to several negative health outcomes. A general overview of fatigue and its relationship with negative health outcomes still lacks in the existing literature. This brings complications for healthcare professionals and researchers to identify fatigue-related health risks. Therefore, this study gives an overview of the prospective predictive value of the main negative health outcomes for fatigue in community-dwelling older adults.

METHODS

PubMed, Web of Knowledge and PsycINFO were systematically screened for prospective studies regarding the relationship between fatigue and negative health outcomes resulting in 4595 articles (last search 5th March 2020). Meta-analyses were conducted in RevMan using Odds ratios (ORs), Hazard ratios (HRs) and relative risk ratios (RR) that were extracted from the included studies. Subgroup-analyses were performed based on (1) gender (male/female), (2) length of follow-up and (3) fatigue level (low, medium and high).

RESULTS

In total, thirty articles were included for this systematic review and meta-analysis encompassing 152 711 participants (age range 40-98 years), providing information on the relationship between fatigue and health outcomes. The results showed that fatigue is related to an increased risk for the occurrence of all studied health outcomes (range OR 1.299-3.094; HR/RR 1.038-1.471); for example, mortality OR 2.14 [1.74-2.63]; HR/RR 1.44 [1.28-1.62]), the development of disabilities in basic activities of daily living (OR 3.22 [2.05-5.38]), or the occurrence of physical decline (OR 1.42 [1.29-1.57]).

CONCLUSION

Overall fatigue increases the risk for developing negative health outcomes. The analyses presented in this study show that fatigue related physical decline occurs earlier than hospitalization, diseases and mortality, suggesting the importance of early interventions.

The operationalization of fatigue in frailty scales: a systematic review

PURPOSE

To identify the different fatigue items in existing frailty scales.

METHODS

PubMed, Web of Knowledge and PsycINFO were systematically screened for frailty scales. 133 articles were included, describing 158 frailty scales. Fatigue items were extracted and categorized in 4 fatigue constructs: "mood state related tiredness", "general feeling of tiredness", "activity based feeling of tiredness" and "resistance to physical tiredness".

RESULTS

120 fatigue items were identified, of which 100 belonged to the construct "general feeling of tiredness" and only 9 to the construct "resistance to physical tiredness". 49,4% of the frailty scales included at least 1 fatigue item, representing 15 ± 9,3% of all items in these scales. Fatigue items have a significantly higher weight in single domain (dominantly physical frailty scales) versus multi domain frailty scales (21 ± 3.2 versus 10.6 ± 9.8%, p=<0,05).

CONCLUSION

Fatigue is prominently represented in frailty scales, covering a great diversity in fatigue constructs and underlying pathophysiological mechanisms by which fatigue relates to frailty. Although fatigue items were more prevalent and had a higher weight in physical frailty scales, the operationalization of fatigue leaned more towards psychological constructs. This review can be used as a reference for choosing a suitable frailty scale depending on the type of fatigue of interest.

Validation of the Wii Balance Board to assess balance modifications induced by increased respiratory loads in healthy subjects

BACKGROUND

There is a link between breathing and balance and posture. When the inspiratory loads are increased by pathologies, there is a decrease of postural control. The increase of the inspiratory load on respiratory muscles is a common feature in various chronic pulmonary pathologies. Consequently, the balance of those patients is likely affected.

RESEARCH QUESTION

The aim of this study is to validate the use of the Nintendo Wii Balance Board (WBB) to assess balance modifications induced by increased respiratory loads in healthy subjects.

METHODS

Thirty-seven healthy young participants (25 ± 4 years old, 17 women) participated in this study. Five different conditions were tested: without anything (control), throughout a mouthpiece, and throughout three inspiratory threshold loads (ITL) at 10% (low), 40% (mid) and 60% (high) of the maximal inspiratory pressure. Each trial lasted for 60 s. Nine parameters were extracted based on center of pressure displacement based on a previously-validated method. ANOVA tests were used to compare the different conditions followed by Bonferroni's corrections.

RESULTS

Highly statistically significant differences (all p <  0.01) and large effect sizes (all ω² > 0.24) were obtained for all parameters between the different loads and the mouthpiece condition. There is a linear relationship between the load and balance perturbation.

SIGNIFICANCE

In this study, we demonstrated the validity of the WBB to detect the effect of the inspiratory load on balance in young healthy subjects. Further studies are needed to determine if such a kind of evaluation can be used in clinics with patients suffering from chronic respiratory disease.

Essential diseases in prescribing: A national Delphi study towards a core curriculum in pharmacotherapy education

AIMS

Prescribing is a core skill for junior doctors, yet 8-10% of their prescriptions contain errors. To ensure adequate training in prescribing, it is important to define the diseases for which junior doctors should be competent to prescribe. The aim of the present study was therefore to identify the essential diseases in prescribing for junior doctors.

METHODS

A two-round Delphi consensus study was conducted among medical specialists, general practitioners, junior doctors, pharmacists and pharmacotherapy teachers from all eight academic hospitals in the Netherlands. Using a five-point Likert scale, the participants indicated for each item on an initial questionnaire whether it should be considered an essential disease for junior doctors. The items for which ≥80% of all respondents agreed or strongly agreed were accepted as essential diseases.

RESULTS

Sixty-two participants completed the Delphi survey. In total, 63 of 220 items were considered to be essential diseases.

CONCLUSION

This is the first Delphi consensus study identifying exact conditions that junior doctors must be able to prescribe for. The essential diseases can be used for training in prescribing and assessment of junior doctors' prescribing competence.

Modern Strategies in the Prevention of Implant-Associated Infections

The application of medical devices either for temporary or permanent use has become an indispensible part of almost all fields of medicine. However, foreign bodies are associated with a substantial risk of bacterial and fungal infections. Implant-associated infections significantly contribute to the still increasing problem of nosocomial infections.

To reduce the incidence of such infections, specific guidelines providing evidence-based recommendations and comprising both technological and nontechnological strategies for prevention have been established. Strict adherence to hygienic rules during insertion or implantation of the device are aspects of particular importance. Besides such basic and indispensable aspects, the development of new materials which could withstand microbial adherence and colonization has become a major topic in recent years. Modification of surface by primarily physico-chemical methods may lead to a change in specific and unspecific interactions with microorganisms and, thus, to a reduction in microbial adherence. Medical devices made out of a material that would be ideally antiadhesive or at least colonization-resistant would be the most suitable candidates to avoid colonization and subsequent infection. However, it appears impossible to create a surface with an absolute “zero”-adherence due to thermodynamical reasons and due to the fact that a modified material surface is in vivo rapidly covered by plasma and connective tissue proteins. Therefore, another concept for the prevention of implant-associated infections involves the impregnation of devices with various antimicrobial substances such as antibiotics, antiseptics, and/or metals.

In fact, already commercially available materials for clinical use such as antimicrobial catheters have been introduced, in part with considerable impact on subsequent infections. However, future studies are warranted to translate the knowledge on the pathogenesis of device-associated infections into applicable prevention strategies.

[Who does my leg belong to after amputation?; informed consent on amputation of body parts]

In the Netherlands, when body parts are amputated as part of a medical procedure the patient's consent is required if this body part is used for, or subjected to, medical tests. The patient's consent is, however, rarely obtained, when body parts are discarded as 'pathological waste'. This can raise concerns, as patients have good reasons and distinct rights to demand a different fate, such as a burial or cremation, for their amputated limb. This article analyses the legal status of an amputated body part. We conclude that, legally, the amputated part does not belong to the hospital or doctor and can therefore not be disposed of at whim, in accordance with the hospital's wishes. Doctors have an obligation to actively inform their patients of their property rights over the amputated limbs and of the alternatives to disposal that are available. Doctors might find themselves exposed to tortuous liability procedures if they dispose of amputated body parts without proper consent.

Interaction Detection with Depth Sensing and Body Tracking Cameras in Physical Rehabilitation

INTRODUCTION

This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation".

OBJECTIVES

This paper presents a camera based method for identifying the patient and detecting interactions between the patient and the therapist during therapy. Detecting interactions helps to discriminate between active and passive motion of the patient as well as to estimate the accuracy of the skeletal data.

METHODS

Continuous face recognition is used to detect, recognize and track the patient with other people in the scene (e.g. the therapist, or a clinician). We use a method based on local binary patterns (LBP). After identifying users in the scene we identify interactions between the patient and other people. We use a depth map/point cloud for estimating the distance between two people. Our method uses the association of depth regions to user identities and computes the minimal distance between the regions.

RESULTS

Our results show state-of-the-art performance of real-time face recognition using low-resolution images that is sufficient to use in adaptive systems. Our proposed approach for detecting interactions shows 91.9% overall recognition accuracy what is sufficient for applications in the context of serious games. We also discuss limitations of the proposed method as well as general limitations of using depth cameras for serious games.

CONCLUSIONS

We introduced a new method for frame-by-frame automated identification of the patient and labeling reliable sequences of the patient's data recorded during rehabilitation (games). Our method improves automated rehabilitation systems by detecting the identity of the patient as well as of the therapist and by detecting the distance between both over time.

Can serious games be incorporated with conventional treatment of children with cerebral palsy? A review

The use of video games in rehabilitation is becoming more popular to clinicians. These games are embedded in off-the-shelf commercial entertainment applications or especially-developed for clinical purposes. Treatment of cerebral palsy (CP) children is a challenging task for clinicians. Lack of motivation and progress monitoring are two important factors clinicians need to deal with. The use of serious games (SG), sometimes referred to as Virtual Rehabilitation (VR), could therefore be an interesting adjuvant to conventional treatment for these patients. This is however a new discipline and many scientific issues remain to be solved. The aim of this paper is to describe available conventional treatment for CP children together with the level of evidence of each approach. A systematic review of the use of SG in rehabilitation is then conducted. 31 papers (7 randomized clinical trials, 16 cohort studies and 8 single-cases studies) were selected and analyzed, and their level of evidence compared to the conventional treatment. These studies reported outcomes for 352 patients. In summary, this review shows that it is difficult to compare those studies despite the large amount of patients. This is due to the lack of standardization in patient rehabilitation strategy and to the use of various clinical scales and scores. This non-standardization in patient follow-up between previously-published works make evidence-based conclusions difficult to obtain in order to support these techniques objectively. The use of SG for rehabilitation purposes currently meets similar issues. This paper proposes standardization strategies in order to improve treatment comparison and SG use in rehabilitation.

Reliability of clinician rated physical effort determination during functional capacity evaluation in patients with chronic musculoskeletal pain

INTRODUCTION

Functional capacity evaluation (FCE) can be used to make clinical decisions regarding fitness-for-work. During FCE the evaluator attempts to assess the amount of physical effort of the patient. The aim of this study is to analyze the reliability of physical effort determination using observational criteria during FCE.

METHODS

Twenty-one raters assessed physical effort in 18 video-recorded FCE tests independently on two occasions, 10 months apart. Physical effort was rated on a categorical four-point physical effort determination scale (PED) based on the Isernhagen criteria, and a dichotomous submaximal effort determination scale (SED). Cohen's Kappa, squared weighted Kappa and % agreement were calculated.

RESULTS

Kappa values for intra-rater reliability of PED and SED for all FCE tests were 0.49 and 0.68 respectively. Kappa values for inter-rater reliability of PED for all FCE tests in the first and the second session were 0.51, and 0.72, and for SED Kappa values were 0.68 and 0.77 respectively. The inter-rater reliability of PED ranged from κ = 0.02 to κ = 0.99 between FCE tests. Acceptable reliability scores (κ > 0.60, agreement ≥80 %) for each FCE test were observed in 38 % of scores for PED and 67 % for SED. On average material handling tests had a higher reliability than postural tolerance and ambulatory tests.

CONCLUSION

Dichotomous ratings of submaximal effort are more reliable than categorical criteria to determine physical effort in FCE tests. Regular education and training may improve the reliability of observational criteria for effort determination.

Surgery for acquired cardiovascular disease: antiseptic treatment of contaminated vein grafts

AIM

Saphenous vein grafts harvested for use as bypass conduits can be contaminated intraoperatively, e.g. by being inadvertently dropped to the floor of the operating room (OR). This study was performed to investigate microorganisms most likely contaminating vein grafts and to assess the possible efficacy of measures to treat potentially contaminated vein grafts antiseptically for further use.

METHODS

In a first step we determined the microbiological flora of the OR using surface cultures and cultures from intentionally dropped vein grafts. Several antiseptic agents (PVP-iodine 10%, octenidinhydrochloride 0.1%, polyhexanide 1%) were evaluated for their in vitro efficacy to disinfect artificially contaminated vein segments. The most promising antiseptic regimen was tested on veins contaminated in a real OR setting. Finally, we tested for possible alterations in mechanical properties of the veins caused by antiseptic treatment.

RESULTS

Coagulase-negative staphylococci where the predominant bacteria recovered from the OR with 59.9%. Antiseptic treatment with a combination of octenidine and PVP-iodine resulted in a higher rate of negative cultures than any single agent. Treatment of 50 saphenous vein grafts contaminated in the OR with the combination regimen resulted in only 3 positive cultural results within 7 days. Mechanical tear-stress testing comparing antiseptically treated vein grafts with controls showed no difference in their resistance to tear stress.

CONCLUSION

Antiseptic treatment of contaminated vein grafts was shown to be effective in a high percentage of cases without altering mechanical properties of grafts and may be an option for the surgeon in case of a contamination.