Magnetization in Microsurgery: Causes and Potential Solutions

Abstract

Microsurgery is a surgical technique to connect blood vessels and nerves of approximately 1mm in diameter. During microsurgery, surgeons use operating microscopes to magnify the operative field and use needles with diameters as small as 0.10mm. The microscopic scale of the needle introduces unique challenges. For example, even a small amount of magnetization of the needle or surgical instrument can create a small magnetic force that interferes with the surgeon’s ability to perform the operation. Over 50 members of the Canadian Society of Plastic Surgeons completed a national survey and it showed that on average, magnetization occurs in 38% of cases. The consequences of magnetization may include damage to the patient’s blood vessels and/or nerves, sub-optimal post-operative recovery, and increased operating room time. We determined that magnetization occurs during microsurgery and identified the magnetic surgical mats and magnetic needle counters as sources of magnetization. Additionally, we propose and demonstrate two possible solutions to magnetization of microsurgical instruments and needles:

1. Thermal annealing treatment of either the surgical instruments or needles,

2. The use of a medical grade handheld demagnetizer in the operating room.

Thermal annealing treatment of manufactured instruments or needles will cause unwanted change in their material properties; hence this treatment has to be performed during the manufacturing process. The use of a medical grade handheld demagnetizer can readily be used during surgery in the operating room and is the recommended solution.