AJ-500A radiofrequency ablation system for tumours

Effective, versatile and relatively inexpensive, radiofrequency thermocoagulation remains the front-runner among the many minimally invasive tumour-ablation options on the market today. In recent years, studies have explored an array of options for controlling and enhancing the ablation effect, including internal probe cooling, slow or pulsed heating, saline infusion and multiprobe arrays.

Luckily, the AJ-500A supports them all.

Simply connect the peristaltic pump and plug in up to three needle electrodes, and the corresponding display(s) will automatically appear on the intuitive tilted touchscreen:

Pulsed (P) mode: once a certain multiple of the initial impedance level has been reached, RF energy automatically switches off to allow cooling until impedance drops below the defined threshold. This impedance-controlled environment is ideal for treating larger tumours, such as hepatic neoplasms.

Often used with the L-shaped internally cooled electrode: has a hollow needle bar that circulates up to 130ml of water per minute from the peristaltic pump, which helps prevent adhesion and carbonation.

Manual (M) mode: RF energy is delivered continuously; once a defined impedance threshold has been reached, a signal tone prompts the user to reposition the probe, for example when performing multi-point ablation.

Often used with the straight internally cooled electrode: has an ergonomic handle to allow quick repositioning when ablating multiple superficial growths. Like its L-shaped counterpart, it features an integrated hollow needle bar with circulation cooling.

TEMP mode: both internally cooled electrodes can also be used in temperature-control mode, in which the RF energy cuts off when a certain temperature is reached. Users can adjust the target temperature depending on the desired ablation width. This mode is particularly useful in “Moving Shot” ablation of thyroid nodules.

C-track mode: a special mode to ensure accurate Cool Needle tract ablation and prevent tumour seeding. When the temperature drops below a specified threshold, the generator prompts the user to stop withdrawing the needle and wait until the target temperature has been re-established.

A-track (affusion) mode: provides precise temperature control while gradually releasing liquid into the environment.

Used with: Adjustable-length water injection needle electrode have small holes approximately 5 mm from the tip to allow saline-modulated ablation, which enhances ablation shape and range when ablating solid, higher-impedance tumours such as pulmonary growths.

Technical specifications

Technology: monopolar RF generator
Applied parts classification: type CF
Generator dimensions: L 444 mm × W 387 mm × H 153 mm
Generator weight: 9.4 kg
Peristaltic pump dimensions: L 335 mm × W 172 mm × H 253 mm
Peristaltic pump weight: 6.3 kg
Working frequency: 471kHz ±10%
Input voltage: 230 V AC
Input power: 500V A
Rated load: 50Ω

Output specifications

Working mode	Rated power	Max. output
Affusion	200 W	450 V
A-track	50 W	450 V
Cool Needle(M)	150 W	670 V
Cool Needle (P)	150 W	670 V
Cool Needle (TEMP)	80 W	550 V
C-track	50 W	330 V