Multi-frequency VEMPs improve detection of present otolith responses in bilateral vestibulopathy

Objective

To investigate whether multi-frequency Vestibular Evoked Myogenic Potential (VEMP) testing at 500, 750, 1,000, and 2,000 Hz, would improve the detection of present dynamic otolith responses in patients with bilateral vestibulopathy (BV).

Methods

Prospective study in a tertiary referral center. BV patients underwent multi-frequency VEMP testing. Cervical VEMPs and ocular VEMPs were recorded with the Neuro-Audio system (v2010, Neurosoft, Ivanovo, Russia). The stimuli included air-conducted tone bursts of 500, 750, 1,000, and 2,000 Hz, at a stimulation rate of 13 Hz. Outcome measures included the percentage of present and absent VEMP responses, and VEMP thresholds. Outcomes were compared between frequencies and type of VEMPs (cVEMPs, oVEMPs). VEMP outcomes obtained with the 500 Hz stimulus, were also compared to normative values obtained in healthy subjects.

Results

Forty-nine BV patients completed VEMP testing: 47 patients completed cVEMP testing and 48 patients completed oVEMP testing. Six to 15 % more present VEMP responses were obtained with multifrequency testing, compared to only testing at 500 Hz. The 2,000 Hz stimulus elicited significantly fewer present cVEMP responses (right and left ears) and oVEMP responses (right ears) compared to the other frequencies (p ≤ 0.044). Using multi-frequency testing, 78% of BV patients demonstrated at least one present VEMP response in at least one ear. In 46% a present VEMP response was found bilaterally. BV patients demonstrated a significantly higher percentage of absent VEMP responses and significantly higher VEMP thresholds than healthy subjects, when corrected for age (p ≤ 0.002). Based on these results, a pragmatic VEMP testing paradigm is proposed, taking into account multi-frequency VEMP testing.

Conclusion

Multi-frequency VEMP testing improves the detection rate of present otolith responses in BV patients. Therefore, multi-frequency VEMPs should be considered when evaluation of (residual) otolith function is indicated.

[Intervention planning in modern renal surgery]

BACKGROUND

Three-dimensional (3D) reconstruction in renal surgery offers significant benefits in planning of the operation itself, in patient education and training fellows.

OBJECTIVE

The goal was to study the possible application and use of 3D reconstruction in modern renal surgery.

METHODS

A literature search in PubMed using keywords "3D" and "renal surgery" within the last 10 years of publication was performed.

RESULTS

The search revealed 655 articles among them 53 reviews. Relevant for this article were 120 articles which included 14 reviews. The publication statistics showed a strong increase in the last 10 years which may reflect the increasing application and demand for 3D technology in the field of renal surgery. Especially in robot-assisted minimally invasive surgery applications, the use of 3D technology was studied more often. The technical standards are not yet uniform and 3D printing in complex renal surgery remains cost- and time-intensive. Nevertheless, the results of the pioneering clinical studies showed positive results, and 3D technology can be used not only in planning the operation, but in patient education and also the training of fellows and staff. A limitation to more complex cases seems to be sensible for this is still a costly tool. To identify complex cases in renal surgery, the established renometric scoring systems should be used more broadly in daily practice to identify patients who would profit most from this technique.

CONCLUSION

In complex renal surgery, 3D reconstruction and modelling is rational; furthermore, it can be useful in patient education and in training of fellows.

Reported thresholds of self-motion perception are influenced by testing paradigm

Background/objective

Different testing paradigms have been proposed to investigate perceptual self-motion thresholds. They can differ regarding the amount of possible motions that patients have to choose from. Objective of this study was to compare the two-option paradigm and twelve-option paradigm, to investigate whether reducing the choice options significantly influences the reported thresholds of self-motion perception of healthy subjects.

Methods

Thirty-three volunteers with no prior vestibular complaints were included and sequentially tested with both paradigms at a random sequence. Perceptual self-motion thresholds were measured using a hydraulic motion platform in the absence of external visual and auditory cues. The platform delivered twelve different movements: six translations and six rotations. Each subject had to report the correct type and direction of movements. Thresholds were determined by a double confirmation of the lowest threshold, in combination with a double rejection of the one-step lower stimulus. Perceptual self-motion thresholds of both paradigms were compared using the mixed model analysis.

Results

The twelve-option paradigm showed significantly higher reported thresholds for yaw rotations and translations left, right and down (p < 0.001), compared to the two-option paradigm. No statistical difference was found for rolls and translations up. No significant gender effect, learning effect and carry-over effect were present in any of the applied motion directions.

Conclusion

Reported thresholds of self-motion perception of healthy subjects are influenced by the testing paradigm. The twelve-option paradigm showed significantly higher thresholds than the two-option paradigm. Results obtained with each testing paradigm should, therefore, be compared to paradigm-specific normative data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11032-y.

Explainable artificial intelligence (XAI): closing the gap between image analysis and navigation in complex invasive diagnostic procedures

Literature review

Cystoscopy is the gold standard for initial macroscopic assessments of the human urinary bladder to rule out (or diagnose) bladder cancer (BCa). Despite having guidelines, cystoscopic findings are diverse and often challenging to classify. The extent of the false negatives and false positives in cystoscopic diagnosis is currently unknown. We suspect that there is a certain degree of under-diagnosis (like the failure to detect malignant tumours) and over-diagnosis (e.g. sending the patient for unnecessary transurethral resection of bladder tumors with anesthesia) that put the patient at risk.

Conclusions

XAI robot-assisted cystoscopes would help to overcome the risks/flaws of conventional cystoscopy. Cystoscopy is considered a less life-threatening starting point for automation than open surgical procedures. Semi-autonomous cystoscopy requires standards and cystoscopy is a good procedure to establish a model that can then be exported/copied to other procedures of endoscopy and surgery. Standards also define the automation levels—an issue for medical product law. These cystoscopy skills do not give full autonomy to the machine, and represent a surgical parallel to ‘Autonomous Driving’ (where a standard requires a human supervisor to remain in the ‘vehicle’). Here in robotic cystoscopy, a human supervisor remains bedside in the ‘operating room’ as a ‘human‐in‐the‐loop’ in order to safeguard patients. The urologists will be able to delegate personal- and time-consuming cystoscopy to a specialised nurse. The result of automated diagnostic cystoscopy is a short video (with pre-processed photos from the video), which are then reviewed by the urologists at a more convenient time.

Microwave observations reveal the deep extent and structure of Jupiter's atmospheric vortices

[Figure: see text].

AB0915-PARE DEVELOPMENT AND USABILITY OF A WEB-BASED PATIENT-TAILORED TOOL TO SUPPORT ADHERENCE TO URATE-LOWERING THERAPY IN GOUT PATIENTS

Background:

Adherence to prescribed urate-lowering therapy (ULT) among gout patients is considered to be among the poorest of all chronic conditions. eHealth programs can be a possible opportunity to foster ULT adherence.

Objectives:

This study describes the development and usability evaluation of a web-based tool to support ULT adherence among gout patients, specifically designed for a complement to usual care.

Methods:

The Integrated Change (I-Change) model was used as theoretical basis for the development. The model combines various socio-cognitive theories and differentiates between three phases: a pre-motivational, a motivational, and a post-motivational phase. In practices, the I-Change gout tool contains three sessions, following the three phases of the I-Change model. Patients receive tailored feedback based on their answers in the form of animated videos and text messages after each session, and are prompted to set specific goals and action plans for their ULT adherence. The content and development of the I-Change gout tool was determined along an iterative process within a steering group of clinicians and researchers, supported by patient interviews and gout specific literature related to key aspects of medication adherence behavior. A cross-sectional mixed methods design was used to test usability of the support tool consisting of a think aloud method and a usability questionnaire.

Results:

The steering group decided on the content of the three sessions of the I-Change gout tool. Depending on the intention to change ULT adherence behavior patients were navigated through the I-Change gout tool, patients with a low intention go through all 3 sessions and patients with a high intention go through the pre- and post-motivational session (figure 1). In total, the I-Change gout tool contains three sessions with 80 questions, 66 tailored textual feedback messages, and 40 tailored animated videos.

Figure 1.

Flowchart of the computer-tailored I-Change gout tool for urate-lowering therapy adherence.

Twenty gout patients and seven healthcare professionals participated in the usability tests. The program end score rating for the gout tool was on average 8.4±0.9 (range 6-10) for patients and 7.7±1.0 (range 6-9) for healthcare professionals. Furthermore, participants reported a high intention to use and/or recommend the program in the future. Yet, participants identified some issues for further improvement of the systems user-friendliness by addressing barriers (e.g. more explicitly navigation) and weaknesses (e.g. technical and health literacy). The I-Change gout tool was updated according suggestions of improvements of the participants.

Conclusion:

This study provides initial support for the usability by patients and healthcare professionals of a ULT adherence I-Change gout tool. Further studies need to be conducted to assess its efficacy and (cost-) effectiveness in daily practice.

Disclosure of Interests:

None declared

Evaluating hearing performance with cochlear implants within the same patient using daily randomization and imaging-based fitting - The ELEPHANT study

Background

Prospective research in the field of cochlear implants is hampered by methodological issues and small sample sizes. The ELEPHANT study presents an alternative clinical trial design with a daily randomized approach evaluating individualized tonotopical fitting of a cochlear implant (CI).

Methods

A single-blinded, daily-randomized clinical trial will be implemented to evaluate a new imaging-based CI mapping strategy. A minimum of 20 participants will be included from the start of the rehabilitation process with a 1-year follow-up period. Based on a post-operative cone beam CT scan (CBCT), mapping of electrical input will be aligned to natural place-pitch arrangement in the individual cochlea. The CI’s frequency allocation table will be adjusted to match the electrical stimulation of frequencies as closely as possible to corresponding acoustic locations in the cochlea. A randomization scheme will be implemented whereby the participant, blinded to the intervention allocation, crosses over between the experimental and standard fitting program on a daily basis, and thus effectively acts as his own control, followed by a period of free choice between both maps to incorporate patient preference. With this new approach the occurrence of a first-order carryover effect and a limited sample size is addressed.

Discussion

The experimental fitting strategy is thought to give rise to a steeper learning curve, result in better performance in challenging listening situations, improve sound quality, better complement residual acoustic hearing in the contralateral ear and be preferred by recipients of a CI. Concurrently, the suitability of the novel trial design will be considered in investigating these hypotheses.

Trial registration

ClinicalTrials.gov: NCT03892941. Registered 27 March 2019.

Comparative Study of Real-Life Management Strategies in Gout: Data From Two Protocolized Gout Clinics

OBJECTIVE

To compare outcomes of 2 gout clinics that implemented different treatment strategies.

METHODS

Patients newly diagnosed with gout and a follow-up of 9-15 months were included. Co-primary outcomes were the proportion of patients reaching a serum uric acid (UA) ≤0.36 mmoles/liter and free of flares. Secondary outcomes were the proportion of patients requiring treatment intensification and experiencing adverse events. One clinic adopted a strict serum UA (≤0.30 mmoles/liter target) strategy, with early addition of a uricosuric to allopurinol, and the other clinic adopted a patient-centered (PC) strategy emphasizing a shared decision based on serum UA and patient satisfaction with gout control. Independent t-tests or chi-square tests were used to test differences in outcomes, and logistic regressions were used to adjust the effect of the treatment center on outcomes for confounders.

RESULTS

In total, 126 and 86 patients had a follow-up mean ± SD of 11.3 ± 1.8 versus 11.1 ± 1.9 months. In the UA strategy, 105 of 126 patients (83%) compared to 63 of 86 (74%) in the PC strategy (P = 0.10) reached the threshold of ≤0.36 mmoles/liter; and 58 of 126 (46%) versus 31 of 86 (36%) were free of flares (P = 0.15). In the UA strategy, 76 of 126 patients (60%) were on allopurinol monotherapy compared to 63 of 86 (73%) in the PC strategy (P = 0.05), yet the number of adverse events was not different (n = 25 [20%] versus n = 20 [23%]; P = 0.55). Adjusting for confounders did not substantially change these associations.

CONCLUSION

A strict UA strategy resulted in a nonsignificantly higher proportion of patients reaching a serum UA ≤0.36 mmoles/liter and being free of flares. This result was accomplished with significantly more therapy intensification. The small sample size plays a role in the significance of results.

Impact of hydraulic retention time on community assembly and function of photogranules for wastewater treatment

Photogranules are dense, spherical agglomerates of cyanobacteria, microalgae and non-phototrophic microorganisms that have considerable advantages in terms of harvesting and nutrient removal rates for light driven wastewater treatment processes. This ecosystem is poorly understood in terms of the microbial community structure and the response of the community to changing abiotic conditions. To get a better understanding, we investigated the effect of hydraulic retention time (HRT) on photogranule formation and community assembly over a period of 148 days. Three laboratory bioreactors were inoculated with field samples from various locations in the Netherlands and operated in sequencing batch mode. The bioreactors were operated at four different HRTs (2.00, 1.00, 0.67, 0.33 days), while retaining the same solid retention time of 7 days. A microbial community with excellent settling characteristics (95-99% separation efficiency) was established within 2-5 weeks. The observed nutrient uptake rates ranged from 24 to 90 mg_N L^-1 day^-1 and from 3.1 to 5.4 mg_P L^-1 day^-1 depending on the applied HRT. The transition from single-cell suspension culture to floccular agglomeration to granular sludge was monitored by microscopy and 16S/18S sequencing. In particular, two important variables for driving aggregation and granulation, and for the structural integrity of photogranules were identified: 1. Extracellular polymeric substances (EPS) with high protein to polysaccharide ratio and 2. specific microorganisms. The key players were found to be the cyanobacteria Limnothrix and Cephalothrix, the colony forming photosynthetic eukaryotes within Chlamydomonadaceae, and the biofilm producing bacteria Zoogloea and Thauera. Knowing the makeup of the microbial community and the operational conditions influencing granulation and bioreactor function is crucial for successful operation of photogranular systems.

Telemonitoring with an implantable loop recorder in outpatient heart failure care : One year follow-up report from a prospective observational Dutch multicentre study

Introduction

In the care of heart failure patients, telemonitoring is receiving growing attention. The main purpose of this study was to determine the effect of continuous telemonitoring with an implantable loop recorder (ILR, Reveal XT), a novel strategy in the management of stable heart failure patients without a cardiac implantable device. Furthermore, little is known about the incidence of subclinical arrhythmias in this specific group of patients.

Materials and Methods

Stable heart failure patients, New York Heart Association Class II and III, without recent hospitalisation or upcoming intervention, were included. After implantation of the ILR there was regular contact with the research nurse on a pre-specified basis. Clinic visits and telephonic interviews were alternated for a minimum of 1 year. Parallel visits to their treating physician continued according to standard care. The treating physician was blinded for the ILR findings, accept for pre-specified, significant arrhythmic events.

Results

Thirty patients were included and followed for a median duration of 12 months. In 13 patients, data from the loop recorder led to therapeutic changes. One patient received a pacemaker. Eight patients developed atrial fibrillation, all subclinical, with a mean burden of 65.8 ± 173.2 min/day.

Conclusion

The use of an ILR could potentially impact patient management. Additional study is needed in different patient populations (e. g. higher risk groups) to assess if an ILR could also impact on endpoints such as heart failure hospitalisation.

Jupiter's interior and deep atmosphere: The initial pole-to-pole passes with the Juno spacecraft

On 27 August 2016, the Juno spacecraft acquired science observations of Jupiter, passing less than 5000 kilometers above the equatorial cloud tops. Images of Jupiter's poles show a chaotic scene, unlike Saturn's poles. Microwave sounding reveals weather features at pressures deeper than 100 bars, dominated by an ammonia-rich, narrow low-latitude plume resembling a deeper, wider version of Earth's Hadley cell. Near-infrared mapping reveals the relative humidity within prominent downwelling regions. Juno's measured gravity field differs substantially from the last available estimate and is one order of magnitude more precise. This has implications for the distribution of heavy elements in the interior, including the existence and mass of Jupiter's core. The observed magnetic field exhibits smaller spatial variations than expected, indicative of a rich harmonic content.

Patients with gout have short telomeres compared with healthy participants: association of telomere length with flare frequency and cardiovascular disease in gout

AIM AND BACKGROUND

Chronic inflammation associates with increased senescence, which is a strong predictor for cardiovascular disease. We hypothesised that inflammation accelerates senescence and thereby enhances the risk of cardiovascular disease in gout.

METHODS

We assessed replicative senescence by quantifying telomere length (TL) in a discovery cohort of 145 Dutch patients with gout and 273 healthy individuals and validated our results in 474 patients with gout and 293 healthy participants from New Zealand. Subsequently, we investigated the effect of cardiovascular disease on TL of all participants. Also, we measured TL of CD4⁺ and CD8⁺ T lymphocytes, B lymphocytes, monocytes, natural killer cells and plasmacytoid dendritic cells. Additionally, we assessed the potential temporal difference in TL and telomerase activity.

RESULTS

TL in PBMCs of healthy donors decreased over time, reflecting normal ageing. Patients with gout demonstrated shorter telomeres (p=0.001, R²=0.01873). In fact, the extent of telomere erosion in patients with gout was higher at any age compared with healthy counterparts at any age (p<0.0001, R²=0.02847). Patients with gout with cardiovascular disease had the shortest telomeres and TL was an independent risk factor for cardiovascular disease in patients with gout (p=0.001). TL was inversely associated with the number of gouty flares (p=0.005).

CONCLUSIONS

Patients with gout have shorter telomeres than healthy participants, reflecting increased cellular senescence. Telomere shortening was associated with the number of flares and with cardiovascular disease in people with gout.

Ethanol gas-phase ammoxidation to acetonitrile: the reactivity of supported vanadium oxide catalysts

The gas-phase ammoxidation of ethanol, a bio-based platform molecule, has been investigated as a possible more sustainable route for the production of acetonitrile, using supported vanadium oxide catalysts. The nature of the interaction between the support and the active species greatly affected the catalytic performance.

TRPV1 dysfunction in cystinosis patients harboring the homozygous 57 kb deletion

Cystinosis is a rare autosomal recessive disorder characterized by lysosomal cystine accumulation due to loss of function of the lysosomal cystine transporter (CTNS). The most common mutation in cystinosis patients of Northern Europe consists of a 57-kb deletion. This deletion not only inactivates the CTNS gene but also extends into the non-coding region upstream of the start codon of the TRPV1 gene, encoding the capsaicin- and heat-sensitive ion channel TRPV1. To evaluate the consequences of the 57-kb deletion on functional TRPV1 expression, we compared thermal, mechanical and chemical sensitivity of cystinosis patients with matched healthy controls. Whereas patients heterozygous for the 57-kb deletion showed normal sensory responses, homozygous subjects exhibited a 60% reduction in vasodilation and pain evoked by capsaicin, as well as an increase in heat detection threshold. Responses to cold, mechanical stimuli or cinnamaldehyde, an agonist of the related nociceptor channel TRPA1, were unaltered. We conclude that cystinosis patients homozygous for the 57-kb deletion exhibit a strong reduction of TRPV1 function, leading to sensory deficiencies akin to the phenotype of TRPV1-deficient mice. These deficits may account for the reported sensory alterations and thermoregulatory deficits in these patients, and provide a paradigm for life-long TRPV1 deficiency in humans.

Hypophosphatemic osteomalacia: an unusual clinical presentation of multiple myeloma

An unusual case of a 75-year-old man is presented who had multiple stress fractures due to adult onset hypophosphatemic osteomalacia, which was the result of Fanconi syndrome, with light chain cast proximal tubulopathy due to multiple myeloma. A 75-year-old man presented with diffuse pain and muscle weakness. He had multiple stress fractures, low serum phosphate, decreased renal tubular reabsorption of phosphate, and normal PTH and FGF23, indicating adult onset hypophosphatemic osteomalacia. Phosphate supplements with calcitriol resulted in clinical recovery and healing of stress fractures. Because of proteinuria, a renal biopsy was performed that revealed Fanconi syndrome with light chain cast proximal tubulopathy and light kappa chains were found in serum and urine. A bone biopsy confirmed the diagnosis of multiple myeloma, and treatment with chemotherapy resulted in cytological and clinical recovery.

Joint position sense error in people with neck pain: A systematic review

BACKGROUND

Several studies in recent decades have examined the relationship between proprioceptive deficits and neck pain. However, there is no uniform conclusion on the relationship between the two. Clinically, proprioception is evaluated using the Joint Position Sense Error (JPSE), which reflects a person's ability to accurately return his head to a predefined target after a cervical movement.

OBJECTIVES

We focused to differentiate between JPSE in people with neck pain compared to healthy controls.

STUDY DESIGN

Systematic review according to the PRISMA guidelines.

METHOD

Our data sources were Embase, Medline OvidSP, Web of Science, Cochrane Central, CINAHL and Pubmed Publisher. To be included, studies had to compare JPSE of the neck (O) in people with neck pain (P) with JPSE of the neck in healthy controls (C).

RESULTS/FINDINGS

Fourteen studies were included. Four studies reported that participants with traumatic neck pain had a significantly higher JPSE than healthy controls. Of the eight studies involving people with non-traumatic neck pain, four reported significant differences between the groups. The JPSE did not vary between neck-pain groups.

CONCLUSIONS

Current literature shows the JPSE to be a relevant measure when it is used correctly. All studies which calculated the JPSE over at least six trials showed a significantly increased JPSE in the neck pain group. This strongly suggests that 'number of repetitions' is a major element in correctly performing the JPSE test.

Amyloid beta-42 (Aβ-42), neprilysin and cytokine levels. A pilot study in patients with HIV related cognitive impairments

HIV-associated dementia (HAD) is associated with amyloid-beta (Aβ) deposition. This study measured CSF and plasma amyloid beta-42 (Aβ-42), neprilysin (NEP) and cytokine levels in HIV-related cognitive impairments (HCI), HIV normal cognitive functioning (NF) and non-HIV controls. Our data showed a trend towards detectable plasma Aβ-42 levels more frequently in HCI (67%), when compared to NF (29%) and controls (10%). We showed elevated IL-8 levels in CSF of HCI compared to NF, although not significant values. The data from this pilot study indicates that CSF IL-8 and plasma Aβ-42 may be interesting biomarkers for the presence of HCI.

[Reliability of Selected Parameters of Cycling Ergospirometry from the PowerCube-Ergo Respiratory Gas Analyser]

This study aimed to investigate the reliability of 1) the key parameters of cycling ergospirometry (maximum power output [Pmax] and oxygen uptake [V̇O2peak], ventilatory thresholds 1 [VT 1] and 2 [VT 2], and cycling efficiency [CE] and gross efficiency [GE]), 2) the commonly used parameters to quantify exhaustion (maximum heart rate [HFmax], respiratory quotient [RQmax], blood lactate concentration [BLAmax], and ratings of perceived exhaustion [RPEmax]), and 3) the kinetics of exercise induced gas exchange measurements (oxygen uptake [V̇O2], carbon dioxide output [V̇CO2], and minute ventilation [V̇E]) using the PowerCube-Ergo metabolic system in consideration of international statistical recommendations. 12 women and 12 men (28 ± 4 years; 23.2 ± 2.4 kg/m(2)) performed two cycling tests (20 watt/min) separated by one week. The reliability was calculated based on differences in means (t test and effect sizes), retest correlation (intraclass correlation coefficient [ICC]), and within-subject variation (standard error of measurement [SEM]). Of the key parameters of cycling ergospirometry, an excellent reliability (ICC ≥ 0.969; p = 0.000) and high accuracy (%SEM ≤ 4.6) were found for Pmax, V̇O2peak, and VT 1. Of the most commonly used parameters to quantify exhaustion, an excellent reliability (ICC = 0.922; p = 0.000) and high accuracy (%SEM = 1.0) existed only for HFmax. The gas exchange measurements (V̇O2, V̇CO2 und V̇E) of the PowerCube-Ergo were all excellently reliable (ICC ≥ 0,991; p = 0.000) and the accuracy of V̇O2 (SEM = 0.10 l/min) and V̇E (SEM = 3.13 l/min) fulfilled the quality guidance of exercise physiology laboratories. For future studies and practical purposes, the results are vital for the decision as to whether a difference between two tests represents a true intervention effect or just a measurement error and for the estimation of required sample sizes.

[Radical prostatectomy. Detection and management of intra- and postoperative complications]

Radical prostatectomy is the most common treatment for organ-confined prostate cancer. Performed without complications and limitations, surgery will allow complete removal of the tumor and, therefore, cure the patient. Operative techniques have been improved during the last few decades to reduce invasiveness of the procedure. Furthermore, optimized perioperative management has shortened hospital stay. To ensure rapid recovery of each patient, early detection of complications is highly relevant. Herein, different scenarios for peri- and postoperative complications are described, and recommendations for best practice solutions are reviewed.