HD, UHD, 4K in mono and stereo – or: how much video does the surgeon need?

Introduction:

All-digital image processing has recently been developed for operation microscopes. The discussion about video microscopy is focused mostly on resolution issues, as it has been the case with consumer electronics. This presentation addresses the aforementioned question as well as other parameters influencing image quality.

Methods:

We fitted two operation microscopes (OpMi Vario, Zeiss, Oberkochen) with a pair of video camera heads each; the first pair consisting of two 3-CCD-video cameras (Panasonic GP-US 932) with HD-(1920 × 1080) pixel resolution at 50 frames per second. The second operation microscope was fitted with two UHD cameras (BM Design Production Camera 4K) with 3820 × 2160 pixel resolution at 25 frames per second. We assessed both systems in terms of spatial resolution of fine structures during microvascular anastomosis with 9/0 suture material under swift movements as well as for colour and greyscale resolution while detecting the blue line during temporal bone dissection.

Results:

Both systems were capable of showing fine suture material even under rapid movements while the operative site filled the frame. In temporal bone dissection, however, the limited colour space of ITU 709 for HD cameras was inferior to the expanded colour space as in UHD (ITU 2020), mostly in terms of greyscale resolution.

Conclusions:

Results show that spatial resolution of the camera image alone does not play the dominant role in electronic image transmission. To represent the operative site true to life, colour and greyscale space is just as important in order to assess anatomic structures. In case video transmission replaces the direct vision through the microscope's binoculars, latency-free image rendering is also a prerequisite for safe surgery.

Publication History

Publication Date:
18 April 2018 (online)