Options for producing intraoperative, high-definition educational videos
The use of high-definition video in surgical education is becoming increasingly popular. Orthopaedic surgeons, trainees, and patients can view thousands of free and paid-access surgical technique videos on the Internet. The AAOS and orthopaedic specialty organizations have recognized the unique educational value associated with this content and have highlighted surgical video theaters during their annual educational meetings.
Thanks to relatively inexpensive, consumer-grade video cameras, surgeons with minimal video production experience can produce high-quality surgical videos. However, the learning curve is steep, with few resources to guide the collection or editing of this content. Bright surgical field lighting, against the dim background of the operative suite, makes obtaining properly exposed video challenging. Adjusting field of view and image resolution may improve image detail or surgical subject centering, but may lead to inappropriate image exposure or distortion due to the camera's wide-angle lens. As a result of these variables, many surgical videos are of poor quality, encumbered by excessive camera movement, an uncentered or overexposed surgical site, or lack of sufficient anatomic detail.
A number of intraoperative video capture methods are available, with varying degrees of production quality, economic constraint, and level of attention required from the operating surgeon. This article provides an overview of the advantages and disadvantages of several options.
Unmanned tripod-mounted cameras
Many surgical videos are produced with the use of stationary, tripod-mounted cameras. After positioning the patient, the surgeon assembles and positions the video camera. The entire surgical procedure is filmed with few changes in camera positioning.
Although a fairly inexpensive option, video produced with this method tends to be of poor quality, because the surgeon's hands, body, or instruments frequently obscure the operative subject. Considerable attention is required to perform the procedure without blocking the camera's view of the operative subject. Additionally, many procedures require repositioning of the operative extremity, necessitating the help of an unscrubbed individual to reposition the camera during the procedure.
Although fewer surgical videos are filmed with the assistance of an unscrubbed videographer, this option typically results in high-quality content, because the videographer can mobilize during the procedure, ensuring appropriate visualization of the operative field. Videographers have access to professional-grade, modular equipment, which is capable of producing content of extraordinary quality. The surgeon can focus on performing the procedure and give little attention to video production.
Unfortunately, video produced with this method is often shot outside the surgeon’s perspective. The surgeon’s hands or instruments may obscure the surgical field during key portions of the procedure, and the economic burden of contracting a videographer is considerable. Additionally, the presence of an unscrubbed videographer may elevate the risk of sterile field contamination.
Ceiling-mounted surgical light cameras
Several surgical light manufacturers produce models that integrate a high-definition video camera into the central handle of an overhead lighting system. This enables relatively unobscured video capture from a bird’s-eye perspective. Even with frequent repositioning of the operative extremity, the surgeon can be fairly confident that the subject is contained within the camera’s field of view, provided the surgical site is well lit.
Although these systems can produce high-definition video from a relatively unobscured point of view, they cost up to $40,000. In addition, the use of this equipment is limited to operating suites in which they are installed.
Head-mounted surgical video cameras
These devices are marketed to surgeons for the purpose of obtaining intraoperative footage and are small enough to fit within the ventilation helmets typically used for arthroplasty. They can also be mounted directly to surgical loupes. This point of view is rarely obscured by the surgeon’s hands or instruments, and repositioning of the operative extremity does not require camera modification mid-case. The surgeon can focus on performing the procedure without diverting attention to video production. This option does not require specialized operating room equipment and is highly portable.
However, these cameras are considerably more expensive than consumer video cameras and typically cost $3,000 to $4,000. They require a wired connection between the video camera and computer that functions to record the video, which limits surgeon mobility. Wearing the device may produce inadvertent camera motion due to head movement.
Furthermore, if surgeons are unable to review a live feed of the video capture, they may be unaware of inappropriate centering of the operative field or a poor lighting environment. Most head-mounted cameras offer video resolutions limited to 720p (1280 pixels wide × 720 pixels tall). The absence of an ultrahigh-definition option limits postproduction editing with the use of cropping or motion-stabilizing software, because using these techniques will produce videos of less than 720p resolution.
Head-mounted consumer video cameras
The use of a head-mounted consumer camera to record surgical procedures was first described in 2011, when a Contour HD camera was mounted to a standard Welch Allyn headlight to record otolaryngology procedures. This technique has expanded over the past 5 years with the use of a number of head-mounted consumer cameras to film ophthalmologic, orthopaedic, urologic, general, and plastic surgery procedures.
Several small consumer video cameras may be worn on the surgeon’s head, providing an ideal point of view for the production of educational content while minimizing surgeon distraction during the procedure. These cameras are relatively inexpensive, ranging from $200 to $500. They do not require either the use of an unscrubbed individual or a wired connection to record content. Some models allow for the recording of ultrahigh-definition video of up to 4k (3840 pixels × 2160 lines).
Potential drawbacks of this option include inadvertent camera movement, limitations in recording time due to battery or removable media capacity, and the difficulty associated with live review of the video recording. These cameras have wide-angle lenses; this makes it easier to capture the surgical subject at the expense of peripheral field distortion, which may be distracting to the viewer. Several of these disadvantages may be successfully mitigated utilizing the techniques described below.
Our preferred technique
After trying several options for intraoperative video production, we have found that a head-mounted consumer video camera provides the best combination of video quality and portability, at the lowest cost. One such device is the GoPro Hero 4 action camera. Its small size, light weight, ultrahigh-definition recording capabilities, exposure options, and wireless video transmission capabilities make it an excellent choice for shooting surgical videos.
The camera is mounted to a surgical headlamp, a set-up that has proven comfortable for procedures in excess of 3 hours. An external battery pack is used to extend the camera's recording time from 1 hour to approximately 10 hours. The battery pack fits in the surgeon's scrub pant pocket and is connected to the camera via a USB cable. A 128GB microSD card enables up to 9 hours of 1080p, 30FPS high-definition video recording.
Using spot metering rather than autoexposure increases the likelihood of appropriate surgical subject exposure under bright operating suite lights. The GoPro App enables the surgeon to monitor a live view of the recording on a tablet device, to ensure appropriate surgical subject centering and exposure. The tablet may be placed in a clear, sterile bag, allowing the camera to be controlled wirelessly during the procedure.
Lens modifications enable the user to swap the original wide-angle "fish-eye" lens with a narrow field-of-view lens more appropriate for surgical application. These lenses minimize wide angle distortion and maximize anatomic detail, drastically improving intraoperative video quality. We have found that the use of a 3.97mm or 4.35mm lens provides the best footage when we desire capturing the entire sterile field. This wide field of view is still narrower than that of the original GoPro Hero 2.92mm lens, and more appropriately records patient positioning, C-arm position, and closed reduction techniques. Use of a 5.4mm or 7.2mm lens more appropriately records fine anatomic detail within the area of dissection. Finally, using motion stabilization software during video editing will artificially stabilize inadvertent head movement, improving the video aesthetics.
Intraoperative video remains a valuable educational tool, second only to direct observation of a surgical procedure. As technology improves, digital video cameras will continue to shrink in size and cost, and produce higher quality content, enabling surgeons to single-handedly produce intraoperative videos of extraordinary educational value. Propagation of this media through surgical video theaters or Internet repositories will undoubtedly enhance the training of surgeons around the world and become a prominent feature of orthopaedic residency education.
Matthew Avery, MD, is a trauma fellow at Washington University School of Medicine, Barnes-Jewish Hospital in St. Louis.
Joshua Tennant, MD, is assistant professor in the department of orthopaedic surgery, University of North Carolina in Chapel Hill.