Ultrasound probe cables are prone to breakage. How can this be addressed?

As an important component of ultrasound, the transducer is expensive (usually equivalent to half the value of the ultrasound machine) and must be used frequently. During the pulling process, its cable is inevitably subjected to bending, pulling, stretching, and squeezing, eventually resulting in disconnection (often occurring at the root of the transducer), causing the ultrasound machine to malfunction.

Composition of Ultrasound Transducer and Cable

Ultrasound transmits ultrasonic waves through the transducer and receives echoes through the transducer. The transducer is an important component of the ultrasonic diagnostic instrument. The task of the ultrasound transducer is to continuously convert electrical signals into ultrasonic signals and ultrasonic signals into electrical signals using the piezoelectric effect and the inverse piezoelectric effect.

Common ultrasound transducers include convex array transducers, linear array transducers, high-frequency linear array transducers, cavity transducers, phased array transducers, and 3D transducers.

Ultrasound transducer components include the plug component, the transducer component (chip, acoustic lens, matching layer, sound-absorbing block, support frame, acoustic head housing), and the cable.

The transducer is connected to the ultrasound machine via a plug (and its pins); the transducer generally has multiple chips, with upper and lower electrodes set inside the transducer, and each is welded with a lead wire to transmit electrical signals; the sound-absorbing block mainly focuses or emits ultrasonic waves through acoustic focusing; the matching layer is located between the chip array and the acoustic lens to reduce the loss of ultrasonic energy; the absorbing block is used to reduce the ultrasonic energy back-radiated by the piezoelectric vibrator.

The cable generally consists of signal lines, ground lines, control lines, power supplies, etc. Some cables have 48 cores, while others have 264 cores. The wires inside the cable are tightly packed, numbering in the hundreds or even hundreds, as thin as hair. The cable must be impedance-matched with the host and transducer, otherwise it will affect the image quality.

Transducer Malfunction

Any transducer cannot avoid natural wear and tear. After exceeding its service life, it will age, wear, deteriorate, and leak electricity;

The temperature, humidity, dust, and prolonged direct sunlight and large temperature differences in the working environment of the ultrasound machine will also adversely affect the transducer; misoperation by the operator during use, or strong vibration of the transducer, or large fluctuations in its operating voltage, may all cause transducer malfunction.

Common transducer malfunctions include: crystal failure, acoustic lens failure, housing damage, and cable failure.

When dark channels or shadows appear in the ultrasound image, a chip short circuit may have occurred, requiring chip replacement; when the ultrasound image is blurry, the transducer may have exceeded its service life, or the ultrasound machine's working environment is poor, requiring transducer replacement and cleaning, and improvement of the ultrasound machine's working environment; when vertical dark stripes appear in the ultrasound image, an acoustic lens malfunction may have occurred, requiring acoustic lens repair.

Transducers are expensive. Only after ruling out ultrasound machine malfunctions (such as power supply failure or monitor failure) should the transducer be disassembled for inspection.

Cable Disconnection Failure and Troubleshooting

When the ultrasound image shows dark channels, interference ripples, snowflake-like flashes, ghosting, or image defects, the ultrasound transducer cable should be suspected of disconnection. This may be caused by the transducer cable being in a bent or twisted state for a long time during actual use or by the operator pulling it forcefully (another reason for wire disconnection is damage to the outer insulation layer). Transducer sheath damage will also affect the transducer cable.

The following are the troubleshooting methods:

(1) Strengthen the transducer cable surface.

If the transducer cable has minor external damage, the damaged area should be immediately wrapped with electrical tape for protection.。

(2) Perform "Minimally Invasive Surgery".

Cut open the outer sheath of the cable, then cut open the outermost overall shielding wire horizontally. Find the broken wire among the hundreds of wires as thin as hair, weld it, and wrap it with transparent tape; use a multimeter to test whetherthe power has been restored to normal. If the test result is good, reconnect the shielding of the damaged wire and wrap it with transparent tape; then test the machine. When the ultrasound machine resumes normal operation, re-weld the outermost overall shielding wire and secure the outer sheath with electrical tape.

Repairing cable disconnections involves a large amount of work, high cost, long time, and low efficiency. Therefore, it is necessary to consider replacing the entire cable when necessary.

(3) Transplant the transducer.

Some transducer cables only contain shielding wires, power wires, and signal wires. After disconnection, they are difficult to repair, and after repair, they cannot be used for a long time. The transducer and cable can be cut at the point of disconnection, and a special protective sleeve can be put on the cable, and its three wires can be pulled out and welded to the circuit board and fixed with hot glue; at the same time, a copper-clad circuit board is installed at the tail of the transducer, and finally the three wires are welded to the circuit board at the tail of the transducer, and the transducer can be restored to use.

This method is only applicable to ultrasound transducers with simple internal cable structures (such as the German Multi-DOPP and Multi-DOPX2 Doppler diagnostic instruments).

Daily Maintenance of Ultrasound

Transducer cable disconnection failures are difficult, high-precision, labor-intensive, and often counterproductive. Therefore, prevention should be prioritized, and daily maintenance of the ultrasound should be strengthened.

(1) Maintain the transducer sheath.

At the connection between the transducer and the cable, there is a rubber sleeve that plays a reinforcing role. It is used to prevent the wire from being bent at a right angle. If the sheath is not properly maintained, resulting in breakage or detachment, it may break the cable. Therefore, the maintenance of the transducer sheath must be strengthened. Once damage is found, it must be replaced immediately (another method is to refill the cable sheath, this method is low in cost and effective).

(2) Standardized operation.

When using the probe, handle it with care. Do not pull it hard, do not allow the cable to be bent, do not strike the probe, drop the probe, or allow the probe to collide with hard objects.

When using ultrasound couplant, strictly prohibit the use of corrosive or self-made couplant. Only use qualified products from regular manufacturers (non-oily couplant).

After using the probe, it must be wiped clean with soft paper (ethanol can be used, absolutely no water, and no organic solvents or acetone). Be sure to wipe off the couplant to prevent mice and cockroaches from biting the cable.

The probe protective box must be kept dry and clean at all times.

The temperature and humidity in the ultrasound room must be controlled within a reasonable range. The power supply must be stable, and the ground wire must be good.

During use, do not ignore any minor abnormalities. If any abnormalities are found, they must be checked immediately.

This information comes from the internet. Please contact us for deletion if there is any infringement.。