A comprehensive review describes the evolution of surgical microscopes

A clear view of anatomical structures is critical to the success of surgery – especially in microsurgery where narrow anatomical cavities or proximity to vulnerable organs and bones can pose a serious threat to a patient’s health. The surgical microscope has become a powerful tool for improving surgical vision.

A comprehensive review of surgical microscopes, authored by Baowei Fei, professor of biotechnology and radiation at the University of Texas at Dallas, and doctoral candidate of bioengineering Ling Ma, tells the evolution of surgical microscopes as they have developed with wider expansion ranges, longer working distances. , better lighting, and more stable support structures. Ma and Fei explain how surgical microscopes are converted to slightly different optical configurations and equipped with special imaging methods and platforms for different surgical applications.

Past the loupe

The first surgical microscope reported in an operating room was used by a young otolaryngology surgeon named Carl Olof Nylén in 1921 at Stockholm University. Nylén used a Brinell-Leitz monocular microscope during surgery on a patient with chronic ear infection. This was a step up from the loupe of a single lens. The device was upgraded a year later by Gunnar Holmgren who developed a binocular microscope for depth perception and a connected light source to accompany the augmentation. Holmgren hardly recognizes modern surgical microscopes with adjustable magnification, clear shadowless lighting, variable working speed to allow surgical instruments to be handled, and a stable, unobstructed view of the entire work area.

Although surgical microscopes were not introduced into neurosurgical operating rooms until 1957, when Theodor Kurze at the University of Southern California removed inflammatory tumors from cranial nerve in 5-year-old patients, surgery is now a major market. for surgical microscopes.

Multi-image, integrated image modes

A surgical microscope has come a long way. In addition to high-precision optics and flexible mechanical design, multivariate visualization features such as 3D display are now introduced, as well as integrated imaging modes. Augmented reality displays, which overlap real-life structures with, say, MRI or OCT images of the structures, improve visibility of the surgical field as well as the multifocal images. Such advanced capabilities are transforming clinical use in the operating room, enabling surgeons to see better and make challenging procedures easier and more successful.

Hyperspectral imaging (HSI) methods and laser speckle differential imaging (LSCI) are particularly promising as they can be used on-demand at any time during surgery and provide real-time diagnostic data as non-invasive imaging methods. and unlabeled. Ma and Fei note that both HSI and LSCI add little complexity to the system and take little effort for physicians to adopt.

The visual capabilities and integrated technologies in surgical microscopes are ever expanding. With advanced communication technologies and advanced platforms supported by virtual reality, large organizations will be able to participate remotely in surgical procedures, sharing a clear view of the surgical field through headsets, smartphones, or screens. large conference room.

Robotic visual platforms allow freedom of movement for the surgeon and allow the entire team to view detailed structures. Integrated technologies, such as an endoscopic microscopy device, can enable the surgeon to “mark” the position of the surgical field and see the same structure at different angles. Such systems enrich the concept of the surgical microscope with state-of-the-art multimodal technology and also provide clear advantages in time, functionality and ergonomics.

Originally used for otolaryngology, surgical microscopes contribute to a wide range of microsurgeries, from lymphatic reconstruction to zero repair. Increased clinical use of surgical microscopes can be expected, and in a wider range of surgical applications.