Towards an understanding of the role of intravesical capsaicin in the treatment of detrusor hyperreflexia

Capsaicin is the pungent extract of red-hot chilli peppers. Chillies were grown as early as 5000 BC in Mexico and have been used medicinally, for a variety of seemingly unrelated disorders, for thousands of years. Animal experiments have demonstrated that capsaicin blocks a C-fibre mediated micturition reflex in spinal cats. The aim of this study was to investigate its role in the treatment of detrusor hyperreflexia due to spinal cord disease. Intravesical instillations of 1-2 mmol/l of capsaicin, dissolved as a powder in 30% alcohol in saline, were effective in 70% of patients with refractory detrusor hyperreflexia. After initial deterioration in voiding symptoms capsaicin caused an increase in the functional bladder capacity and decrease in the amplitude of hyperreflexic detrusor contractions. The beneficial effect of a single instillation lasted for 3-6 months. Even after repeated instillations over 5 years there was no evidence of pre-malignant or malignant changes in biopsies from bladders thus treated. Suprapubic discomfort during instillations was reduced by the prior use of intravesical lignocaine (40ml of 2% for 20 mins) or by anaesthetising the bladder with iontophoresis of intravesical lignocaine (electromotive drug administration) before capsaicin. Cryostat sections of flexible cystoscopic biopsies before and 6 weeks after capsaicin treatment were stained with the neuronal markers S 100 and PGP 9.5. By using computerized image analysis of lamina propria nerve densities ('MiniMOP' for S 100 and 'Seescan' imaging for PGP 9.5) it was found that intravesical capsaicin caused a reduction in densities of the presumptive sensory suburothelial nerves. Early data using electron microscopy seemed to show a reduction in the densities of clear and dense cored vesicles after capsaicin treatment. These findings indicate that capsaicin causes a sensory denervation the bladder in these patients. Intravesical capsaicin is a significant advance in Uro-Neurology and is likely to lead to the application of other vanilloids, such as resiniferatoxin, in the treatment of detrusor hyperreflexia

Pseudo-Haptics for Rigid Tool/Soft Object Interaction Feedback in Virtual Environments

This paper proposes a novel pseudo-haptics soft object stiffness simulation technique which is a marked improvement to currently used simulation methods and an effective low-cost alternative to expensive 3-DOF haptic devices. Soft object stiffness simulation is achieved by maneuvering an indenter avatar over the surface of a virtual soft object by means of an input device, such as a mouse, a joystick, or a touch-sensitive tablet. The alterations to the indenter avatar behavior produced by the proposed technique create for the user the illusion of interaction with a hard inclusion embedded in the soft object. The proposed pseudo-haptics technique is validated with a series of experiments conducted by employing three types of 2-DOF force-sensitive haptic surfaces, including a touchpad, a tablet with an S-pen input, and a tablet with a bare finger input. It is found that both the sensitivity and the positive predictive value of hard inclusion detection can be significantly improved by 33.3% and 13.9% respectively by employing tablet computers. Using tablet computers could produce results comparable to direct hand touch in detecting hard inclusions in a soft object. The experimental results presented here confirm the potential of the proposed technique for conveying haptic information in rigid tool / soft object interaction in virtual environments

Has robotic prostatectomy determined the fall of the laparoscopic approach?

© The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).Robotic Assisted Laparoscopic Prostatectomy (RALP) has revolutionised the surgical management of localised Prostate Cancer in the modern era. The surgeon is provided with greater precision, more versatile dexterity and an immersive three-dimensional visual field. The impressive hardware facilitates, for example, the dissection of the peri-prostatic fascia, whilst preserving the neurovascular bundle, or the suturing of the vesico-urethral anastomosis. Prior to RALP, Laparoscopic Radical Prostatectomy (LRP) represented the first venture into the minimally invasive world. Associated with more cumbersome ergonomics, LRP has a significant learning curve when compared with the robotic approach. There has been a paucity, until recently, of high-quality literature comparing outcomes between the two operations, including the attainment of the Pentafecta of survivorship: biochemical recurrence-free, continence, potency, no postoperative complications and negative surgical margins.Peer reviewedFinal Published versio

Immune checkpoint blockade – a treatment for urological cancers?

In the last few years there have been concerted attempts at using the power of the immune system as an effective treatment option for cancer. This has become possible since our understanding of the workings of the immune system improved. Tumours form because of failure of the organism to destroy a rogue, mutated cell in an appropriate way.This article is protected by copyright. All rights reserved

Morphological Computation of Haptic Perception of a Controllable Stiffness Probe

When people are asked to palpate a novel soft object to discern its physical properties such as texture, elasticity, and even non-homogeneity, they not only regulate probing behaviors, but also the co-contraction level of antagonistic muscles to control the mechanical impedance of fingers. It is suspected that such behavior tries to enhance haptic perception by regulating the function of mechanoreceptors at different depths of the fingertips and proprioceptive sensors such as tendon and spindle sensors located in muscles. In this paper, we designed and fabricated a novel two-degree of freedom variable stiffness indentation probe to investigate whether the regulation of internal stiffness, indentation, and probe sweeping velocity (PSV) variables affect the accuracy of the depth estimation of stiff inclusions in an artificial silicon phantom using information gain metrics. Our experimental results provide new insights into not only the biological phenomena of haptic perception but also new opportunities to design and control soft robotic probes

Alpha blockers in the management of ureteric lithiasis:A meta-analysis

INTRODUCTION: Effective medical expulsion for ureteric stones with α-blockers offers numerous advantages over surgical alternatives. However, its effectiveness remains uncertain and with the publication of new trial data, the available evidence requires reappraisal.OBJECTIVE: The aim of this study was to assess the efficacy of α-blockers the management of ureteric lithiasis.METHODS: A systematic review of the literature, with predefined search criteria, was conducted using PubMed and Embase. All randomised trials comparing α-blocker monotherapy to placebo or standard therapy were included. Stone expulsion rate was the primary outcome measure. Secondary outcome measures were time to stone expulsion, analgesic usage and pain scores. Subgroup analyses assessed individual adrenergic antagonists and variations in standard therapy. Sensitivity analysis was based on stone location, stone size, Cochrane Risk of Bias score and study protocol. Summary effects were calculated using a random-effect model and presented as Relative risks (RR) and mean differences (MD) for dichotomous and continuous outcome measures, respectively.RESULTS: Sixty-seven studies randomising 6654 patients were included in the meta-analysis. Stone expulsion rates improved with α-blockers (RR, 1.49; 95% CI 1.38-1.61). Contrast enhanced funnel showed evidence of publication bias. Stone expulsion time was 3.99 days (CI -4.75 to -3.23) shorter with α-blockers. Similarly, patients required 106.53 mg [CI -148.20 to -64.86] less diclofenac compared with control/placebo, and had 0.80 [CI -1.07 to -0.54] fewer pain episodes. Visual Analogue Scores were also reduced, -2.43 [CI -3.87 to -0.99]. All formulations of α-antagonists all demonstrated beneficial effects over conservative treatment/placebo. Sensitivity analysis demonstrated significant effects of stone location, stone size and study design.CONCLUSIONS AND RELEVANCE: Despite the opposing results of recently published trial, current evidence continues to demonstrate a potential benefit of α-blocker treatment particularly for distal stones over 5 mm.</p