What are the functions of medical nickel-titanium guidewires?

What are the functions of medical nickel-titanium guidewires?

The different structures of guidewires (design of the guidewire sheath and core wire) determine the different characteristics of the guidewires. Different manufacturers and series of guidewires each have their own features. So, what are the functions of medical nickel-titanium guidewires?

What are the functions of medical nickel-titanium guidewires?

1. The front end of the guidewire is elastic, which does not damage tissue and is very smooth when wet. It can explore the bile duct or pancreatic duct lumen, enter the bile duct or pancreatic duct, pass through obstructions or narrow areas, guide accessories, and improve the success rate. It is the foundation for successful diagnosis and treatment. In angiography, guidewires can be used to explore the target catheter. Placing the catheter at the opening, the guidewire can enter at the 11 o'clock direction to guide entry into the bile duct. When used in combination with other instruments, attention should be paid to adjusting the distance between the guidewire and the catheter. A longer segment of guidewire can also be inserted to bounce and fold into a loop to hook into the target bile duct. The guidewire entering the target bile duct is key to the smooth progress of the surgery and achieving the expected diagnostic and therapeutic effect.

2. Using guidewires to exchange various instruments makes surgery more accurate and safer. Flexible use of guidewires shortens surgery time. During angiography, an intelligent knife with a guidewire can be used directly, deciding whether to cut as needed. If cutting the guidewire inserted into the bile duct is required, the cutter will not easily slip out of the bile duct, saving surgery time. After cutting, if treatment is needed, the guidewire can be advanced again into the bile duct or pancreatic duct, the cutting knife withdrawn, and the corresponding instruments replaced again. It is important not to remove the guidewire during the operation, as re-entering the original duct can be difficult after removal. When implanting double or multiple stents for hilar tumors, double guidewires can be used. Flexible and successful use of guidewires can significantly improve work efficiency. This group showed an average surgery time reduction of about 9 minutes.

3. Behind the front end of the guidewire is a steel wire, so the strength of the guidewire can be used to increase insertion force, guiding baskets and stents to the target position. The rigidity of the guidewire can also be used to change the direction of the duodenum, making angiography and cutting smoother and reducing complications. When removing intrahepatic bile duct stones, the guidewire needs to be placed into the target bile duct, then a stone retrieval balloon or basket is advanced along the guidewire to remove the stones. Also, whether the guidewire can be placed into the target bile duct before stent placement is key to success. Without the rigidity of the guidewire, this work cannot be done.

4. When operation is difficult and the catheter repeatedly enters the pancreatic duct, the diaphragm between the bile duct and pancreatic duct can be pulled toward the pancreatic duct side, slightly separating the openings of the bile duct and pancreatic duct. The originally curved pancreatic duct will slightly straighten, facilitating catheter advancement into the bile duct. During EST, excessive injection of contrast agent can cause high pressure in the pancreatic duct, damaging the duct wall epithelium and acinar cells due to the toxicity of the contrast agent. The pancreatic duct and parenchyma can be damaged by activation of pancreatic enzymes by duodenal contents, causing autodigestion. Damage to the pancreatic duct wall is minimal, reducing the incidence of postoperative pancreatitis and hyperamylasemia. The radiopacity of the guidewire can reduce the use of contrast agents, lowering the incidence of cholangitis and pancreatitis.

What are the specifications of medical nickel-titanium guidewires?

Like guidewire catheters, the specifications of guidewires produced by different manufacturers vary, and the expression of specifications also differs. There are two types of domestic guidewires: one is a long guidewire longer than 1.3 meters, thicker and suitable for large catheters over 6F in length. The other is a short guidewire less than 1.3 meters, thinner and suitable for small catheters less than 5F in length. This guidewire has a straight fixed core with a soft segment of about 5 cm at the front end.