e-VF Handheld Electronic Von Frey of original design

The UB Electronic Von Frey of original design, for automatic assessment of Hypersensitivity and Allodynia in rats and mice, automatically records the animal response to user-controlled application of force rate.

A touch stimulator transducer is mounted on a Perspex handle, so that routine procedures may be employed to examine and test the animal skin sensitivity. A prism of original design is of great help to localize the aimed stimulation area

The completion of each test may be indicated either by the sudden release of the paw or by pressing the external foot-pedal. The display then gives the operator a summary of the results of the test (i.e. force and time corresponding to the animal response).

The rate of application of the force is set by the operator and the e-VF includes software tools that help the operator in consistently applying the force at the desired rate.

The device includes as standard both a control unit with internal memory and the NEW DCA software for signal monitoring, data transfer and analysis. The results of several hundred tests may be stored in the e-VF, be browsed on the control unit and/or trasferred to a PC in proprietary, Excel (.xls) or text (.txt) format, to be managed by most statistical analysis packages available on the market.

The instrument includes:

an electronic unit
a touch stimulator with a viewing prism of original design
the software

The 37450-278 Base assembly for plantar stimulation, or with the self-supporting perforated platforms 37450-045 / 37450-085 (see picture), can be purchased separately to complete the set-up, when the stimulation target is the rodent plantar surface.

e-VF

View the embedded image gallery online at:
https://www.ugobasile.com/products/catalogue/pain-and-inflammation/item/78-38450-e-vf-electronic-von-frey#sigProId211ceedb05

Additional Info

Resolution: 0.1g	DCA Software included - NEW 2014 Release
Maximum Applicable Force: 1000g	Location of the target via the original prism-design
User-controlled application of force rate	Automatic recording of animal response

* Speaking about force, although the sensor can detect forces from 0 to 1000g, it is reasonable to set the device lower limit to 5g, given by difficulty, even for the most skilled user, to apply forces below this threshold.

Operation
Commands	via soft-buttons
Read-out	multifunction graphic display
Starting	via keys on the Controller front panel
Force Range	up to 1000 grams (maximum force can be preset)
Force increasing rate	monitored via the Ratemeter on the electronic unit, or via the slope function on the PC
Latency Time	read-out on the graphic display, in 0.1 s steps
Connection to PC	via USB cable (A to mini-B)
Power Requirement	either battery operated, or via USB cable connected to PC or universal converter (85-264 VAC, 50-60Hz)
Operating Temperature	10° to 40° C
Sound Level	negligible
Pollution Degree	≤ 2
Physical
Total Weight	0.8 Kg
Shipping Weight	2.7 Kg approx.
Packing Dimensions	46 x 38 x 27 cm
Warranty
38450 is covered by a 24-month warranty

Impaired cutaneous sensation is usually first manifested in a loss of light touch detection. The Electronic Von Frey was developed to quantify light touch in the laboratory animal.

The classic instrument for test of touch sensitivity is the Von Frey hair or, more specifically, the Semmes- Weinstein set of Von Frey Hairs, i.e., 20 monofilaments in a linear scale of physical force.

The hair is pressed against the skin, the force applied increases with increasing hand pressure, until the hair bends; once the hair is bent, increasing hand approach causes further bend, but negligible additional force on the skin. In this way, a given filament always applies the same force, not subject to variation by the energy of the operator.

The Semmes-Weinstein set can be used on rodents (which respond to light touch of the paw, if they feel it, by a paw withdrawal reflex). However, the involved procedure is tedious and time-consuming because several stimulations must be performed for a single test (i.e. a different filament for each force level).

Compared to the classic Von Frey Hairs, the Electronic Von Frey device (e-VF) has the advantage of ensuring a continuous force application along the whole force capacity of the sensor (i.e. 1-1000 gf), by using a rigid metal tip, and the capability to record the animal response automatically.

Moreover, the metal tip used in the e-VF is the same as the one used in the classic Ugo Basile Dynamic Plantar Aesthesiometer (PN 37450), allowing consistent comparison of results among the two instruments.

38450	EVF Electronic Von Frey consisting of:
38450-001	Electronic Unit
38450-004	Touch Stimulator Transducer, with handle, including
	38450-310 Glass Prism
	38450-330 Filament, with magnetic fixing
38450-323	External trigger switch (foot pedal)
52010-325	USB Lead
E-AU 059	Universal Power Supply
E-AU 041	USB pen-drive, including
	38450-302 Instruction Manual
	DCA Software

Optional

37450-278	Base assembly for plantar stimulation, including support with columns, perforated metal sheet and multiple-configuration animal-enclosure, from 3 to 12 spaces.
37450-005	Large Perforated Metal Sheet
37450-045	Large Perforated Metal Sheet, with 4 legs, 40cm height (animal enclosure 37000-006 is not included and should be ordered separately)
37450-085	Large Perforated Metal Sheet, with 4 legs, 80cm height (animal enclosure 37000-006 is not included and should be ordered separately)