Objective: Phantoms that mimic healthy or diseased organ properties can complement animal models for surgical planning, training, and medical device development. If urodynamic studies rely on pressure-volume curves to assess lower urinary tract symptoms, there is an unsatisfied need for a bladder phantom that accurately mimics the bladder stretching capabilities and compliant behaviour during physiological filling. 
Approach: We demonstrate the suitability of water-soluble 3D-printed moulds as a versatile method to fabricate accurate phantoms with anatomical structures reconstructed from medical images. We report a phantom fabricated with silicone rubber. A wire net limits the silicone expansion to model the cystometric capacity. A mathematical model describes the pressure increase due to passive hyperelastic properties. 
Main results: The phantom reproduces the bladder’s mechanical properties during filling. The pressure-volume curve measured on the phantom is typical of cystometric studies, with a compliance of 25.2 ± 1 mL cmH_2O^(-1). The root-mean-square error between the theoretical model and experimental data is 2.7 cmH_2O. The compliance, bladder wall thickness, cystometric capacity and pressure near the cystometric capacity of the phantom can be tuned to mimic various pathologies or human variability. 
Significance: The manufacturing method is suitable for fabricating bladder and other soft and hollow organ phantoms. The mathematical model provides a method to determine design parameters to model healthy or diseased bladders. Soft hollow organ phantoms can be used to complement animal experimentations for developing and validating medical devices aiming to be anchored on these organs or monitor their activity through pressure and strain measurement. 

This work presents a setup for chronic monitoring of spontaneous epileptic seizures in rats under kainic acid. The system allows to record the vagus nerve electroneurogram at 40 kS/s and the electroencephalogram at 250 S/s using an USB-6212 multifunction I/O-device. The system includes a video channel (20 fps) controlled by a Raspberry Pi 4 Model B.A slipring allows the rat to move freely. Quick cage cleaning is possible through a movable base. The chronic setup was tested on a Wistar rat after status epilepticus induction, using kainic acid. The system appears to be robust and reliable enough to record status epilepticus, making it suitable for more extended experiments in epileptic rats.

This work presents an automated analysis algorithm to detect action potentials (APs) in a nerve and quantify its activity. The algorithm is based on template matching. The templates are automatically adapted to individual AP shapes that vary depending on the nerve fibers from which the AP originates, and the recording setup used. The algorithm was validated by quantifying vagus nerve activity recorded during in vivo experiments in a rat model. The MATLAB version of the code is available in open access on GitHub 1 .

Infrared Neural Stimulation (INS) is a novel neuromodulation technique involving a rapid temperature increase of the neuron membrane, resulting in action potential triggering. This paper describes an experimental setup developed to measure the spatiotemporal temperature gradients at the surface of an ex vivo sciatic nerve. The setup is also designed to measure the conduction velocity of the nervous fibers excited by INS, with the aim of determining the type of fibers activated during optical stimulation. Two animal experiments successfully validated the setup and provided encouraging results on (1) the impact of heat accumulation on INS and (2) the difference in nerve fibers excited by optical and electrical nerve stimulation.

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