Penile rehabilitation for postprostatectomy erectile dysfunction.

BACKGROUND: Despite efforts to preserve the neurovascular bundles with nerve-sparing surgery, erectile dysfunction remains common following radical prostatectomy. Postoperative penile rehabilitation seeks to restore erectile function but results have been conflicting. OBJECTIVES: To evaluate the effects of penile rehabilitation strategies in restoring erectile function following radical prostatectomy for prostate cancer. SEARCH METHODS: We performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase), the Cochrane Library, Web of Science, clinical trial registries (ClinicalTrials.gov, International Clinical Trials Registry Platform) and a grey literature repository (Grey Literature Report) from their inception through to 3 January 2018. We also searched the reference lists of other relevant publications and abstract proceedings. We applied no language restrictions. SELECTION CRITERIA: We included randomised or quasi-randomised trials with a parallel or cross-over design. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. Two review authors independently screened the literature, extracted data, assessed risk of bias and rated quality of evidence according to GRADE on a per-outcome basis. Primary outcomes were self-reported potency, erectile function measured by validated questionnaires (with potency defined as an International Index of Erectile Function (IIEF-EF) score of 19 or greater and or an IIEF-5 of score of 17 or greater) and serious adverse events. For all quality of life assessments on a continuous scale, higher values indicated better quality of life. MAIN RESULTS: We included eight randomised controlled trials with 1699 participants across three comparisons. This abstract focuses on the primary outcomes of this review only.Scheduled phosphodiesterase type 5 inhibitors (PDE5I) versus placebo or no treatmentScheduled PDE5I may have little or no effect on short-term (up to 12 months) self-reported potency (risk ratio (RR) 1.13, 95% confidence interval (CI) 0.91 to1.41; very low quality evidence), which corresponds to 47 more men with self-reported potency per 1000 (95% CI 33 fewer to 149 more) and short-term erectile function as assessed by a validated instrument (RR 1.11, 95% CI 0.80 to 1.55; very low quality evidence), which corresponds to 28 more men per 1000 (95% CI 50 fewer to 138 more), but we are very uncertain of both of these findings. Scheduled PDE5I may result in fewer serious adverse events compared to placebo (RR 0.32, 95% CI 0.11 to 0.94; low quality evidence), though this does not appear biologically plausible and may represent a chance finding. We are also very uncertain of this finding. We found no long-term (longer than 12 months) data for any of the three primary outcomes.Scheduled PDE5I versus on-demand PDE5I Daily PDE5I appears to result in little to no difference in both short-term and long-term (greater than 12 months) self-reported potency (short term: RR 0.97, 95% CI 0.62 to 1.53; long term: RR 1.00, 95% CI 0.60 to 1.67; both very low quality evidence); this corresponds to nine fewer men with self-reported short-term potency per 1000 (95% CI 119 fewer to 166 more) and zero fewer men with self-reported long-term potency per 1000 (95% CI 153 fewer to 257 more). We are very uncertain of these findings. Daily PDE5I appears to result in little to no difference in short-term and long-term erectile function (short term: RR 1.00, 95% CI 0.65 to 1.55; long term; RR 0.74, 95% CI 0.48 to 1.14; both very-low quality evidence), which corresponds to zero men with short-term erectile dysfunction per 1000 (95% CI 80 fewer to 125 more) and 119 fewer men with long-term erectile dysfunction per 1000 (95% CI 239 fewer to 64 more). We are very uncertain of these findings. Scheduled PDE5I may result in little or no effects on short-term adverse events (RR 0.69 95% CI 0.12 to 4.04; very low quality evidence), which corresponds to seven fewer men with short-term serious adverse events (95% CI 18 fewer to 64 more), but we are very uncertain of these findings. We found no long-term data for serious adverse events.Scheduled PDE5I versus scheduled intraurethral prostaglandin E1At short-term follow-up, daily PDE5I may result in little or no effect on self-reported potency (RR 1.10, 95% CI 0.79, to 1.52; very low quality evidence), which corresponds to 46 more men per 1000 (95% CI 97 fewer to 241 more). Daily PDE5I may result in a small improvement of erectile function (RR 1.64, 95% CI 0.84 to 3.20; very low quality evidence), which corresponds to 92 more men per 1000 (95% CI 23 fewer to 318 more) but we are very uncertain of both these findings. We found no long-term (longer than 12 months) data for any of the three primary outcomes.We found no evidence for any other comparisons and were unable to perform any of the preplanned subgroup analyses based on nerve-sparing approach, age or baseline erectile function. AUTHORS' CONCLUSIONS: Based on mostly very-low and some low-quality evidence, penile rehabilitation strategies consisting of scheduled PDE5I use following radical prostatectomy may not promote self-reported potency and erectile function any more than on demand use.

Camera phone-based quantitative analysis of C-reactive protein ELISA.

We demonstrate the use of a camera phone as a low-cost optical detector for quantitative analysis of a high-sensitivity C-reactive protein (hs-CRP) enzyme-linked immunosorbent assay (ELISA). The camera phone was used to acquire images of the ELISA carried out in a conventional 96 well plate. Colorimetric analysis of the images was used to determine a standard curve that exhibited excellent agreement with a fitted 4-parameter logistic model (R²=0.998). The limit of detection (LOD) for this approach was determined to be 0.026 ± 0.002 µg/ml (1.035 ± 0.079 µM) CRP. Furthermore, these results were found to be in very close agreement with measurements obtained for the same assay using a laboratory-based instrument. These findings indicate the basic technology to enable low-cost quantitative home-based monitoring of an important clinical biomarker of inflammatory disease may already be present in the patient's home.

Implant positioning system using mutual inductance.

Surgical placement of implantable medical devices (IMDs) has limited precision and post-implantation the device can move over time. Accurate knowledge of the position of IMDs allows better interpretation of data gathered by the devices and may allow wireless power to be focused on the IMD thereby increasing power transfer efficiency. Existing positioning methods require device sizes and/or power consumptions which exceed the limits of in-vivo mm-sized IMDs applications. This paper describes a novel implant positioning system which replaces the external transmitting (TX) coil of a wireless power transfer link by an array of smaller coils, measures the mutual inductance between each coil in the TX array and the implanted receiving (RX) coil, and uses the spatial variation in those mutual inductances to estimate the location of the implanted device. This method does not increase the hardware or power consumption in the IMD. Mathematical analysis and electromagnetic simulations are presented which explain the theory underlying this scheme and show its feasibility. A particle swarm based algorithm is used to estimate the position of the RX coil from the measured mutual inductance values. MATLAB simulations show the positioning estimation accuracy on the order of 1 mm.

Fundamental sensing limit of electrochemical glucose sensors.

This paper investigates the inherent sensitivity limit, deactivation of glucose oxidase, of a glucose oxidase based electrochemical glucose sensor for in vivo monitoring of blood glucose concentration. Results in this paper show that the current density sensitivity to glucose decreases from 1200 nA/mm(2)/mM at initial implantation to 100 nA/mm(2)/mM after an implantation time of 2 years, when degradation due to glucose oxidase deactivation only is considered. Even as the sensor signal strength decreases, if the sensing electronics are sufficiently discriminating then a useful measure of blood glucose concentration can be extracted. This work aims to determine both how the glucose oxidase based sensor's signal-to-noise ratio degrades over long time scales and the electronic circuit requirements to achieve multi-year device lifetimes. Two sensing amplifier techniques are presented which can be used to detect the signal generated by the sensor. The noise performance of each technique is compared with the noise performance of the sensor and mutli-year lifetimes are shown to be feasible.

Adaptive resolution ADC array for neural implant.

This paper describes an ADC array for an implantable prosthetic processor which digitizes neural signals sensed by a microelectrode array. The ADC array consists of 96 variable resolution ADC base cells. The base ADC has been implemented in 0.13 microm CMOS as a 100kS/s SAR ADC whose resolution can be varied from 3 to 8-bits with corresponding power consumption of 0.23 microW to 0.90 microW achieving an ENOB of 7.8 at the 8-bit setting. The resolution of each ADC cell in the array is varied according to neural data content of the signal from the corresponding electrode. Resolution adaptation reduces power consumption by a factor of 2.3 whilst maintaining an effective 7.8-bit resolution across all channels.

Optimal operating frequency in wireless power transmission for implantable devices.

This paper examines short-range wireless powering for implantable devices and shows that existing analysis techniques are not adequate to conclude the characteristics of power transfer efficiency over a wide frequency range. It shows, theoretically and experimentally, that the optimal frequency for power transmission in biological media can be in the GHz-range while existing solutions exclusively focus on the MHz-range. This implies that the size of the receive coil can be reduced by 10(4) times which enables the realization of fully integrated implantable devices.

Power feasibility of implantable digital spike sorting circuits for neural prosthetic systems.

A new class of neural prosthetic systems aims to assist disabled patients by translating cortical neural activity into control signals for prosthetic devices. Based on the success of proof-of-concept systems in the laboratory, there is now considerable interest in increasing system performance and creating implantable electronics for use in clinical systems. A critical question that impacts system performance and the overall architecture of these systems is whether it is possible to identify the neural source of each action potential (spike sorting) in real-time and with low power. Low power is essential both for power supply considerations and heat dissipation in the brain. In this paper we report that state-of-the-art spike sorting algorithms are not only feasible using modern complementary metal oxide semiconductor very large scale integration processes, but may represent the best option for extracting large amounts of data in implantable neural prosthetic interfaces.