Application of a newly developed, highly sensitive camera and a 3-dimensional high-definition television system in experimental ophthalmic surgeries

Magnification and Refocusing Comparison in Cataract Surgery Using a Heads-Up Three-Dimensional Visualization System versus Conventional Binocular Microscopy

Purpose

To compare magnification and refocusing during phacoemulsification with the NGENUITY® 3-D Visualization System (3-D) versus the conventional microscope (CM) OPMI LUMERA 700.

Setting

This study was performed in the Department of Anterior Segment of the Fundación Hospital Nuestra Señora de la Luz.

Design

Prospective, randomized, cross-sectional, multi-surgeon, and comparative study.

Methods

This study enrolled 100 patients (eyes) scheduled for phacoemulsification to measure the number of times changes in focusing and magnification were needed during cataract surgery.

Results

Our study included 100 patients. From the endpoints evaluated, "zoom-in" showed statistically significant differences for all of the four predefined cataract surgery steps (means: Step 1, 0.38 (CM) vs 0.08 (3-D); Step 2, 0.36 (CM) vs 0.06 (3-D); Step 3, 0.54 (CM) vs 0.22 (3-D); Step 4, 0.56 (CM) vs 0.24 (3-D); all comparisons, p <0.05). In Step 4, there was a statistically significant increased use of "focus-out" for the 3-D system (mean 0.16 (CM) vs 0.58 (3-D); p <0.05). "Focus-in" and "zoom-out" showed no group differences for all steps. The duration of surgery with the 3-D system was longer at each step and overall. The percentage of light intensity did not show a statistically significant difference between both systems, with a mean of 99.45 for CM vs 98.43% for the heads-up system.

Conclusion

The heads-up 3-D system is a safe option that offers excellent magnification for anterior segment visualization. The surgical time is longer, but adjusting settings like light intensity and brightness may facilitate some surgical steps early in the learning curve.

Initial experience with three-dimensional heads-up display system for cataract surgery - A comparative study

Purpose:

To compare the complication rates, surgical time and learning curve using the 3-D Heads up display system in comparison with the conventional microscope for routine cataract surgery.

Methods:

Consecutive consenting adults with uncomplicated cataract were offered phacoemulsification using the 3-D Heads up display system (ARTEVO 800 Carl Zeiss Meditec) or the conventional microscope (Zeiss Lumera 700) by two experienced surgeons. Surgical time, measured from start of corneal incision to removal of microscope from the surgical field and complication rates were compared between the groups.

Results:

Of the 343 eyes enrolled, 100 (29%) underwent surgery using the 3-D Heads up display system. The surgical time for 3-D Heads up display system was significantly higher in the 3-D group (8.4 ± 2.1 vs. 6.5 ± 1.8 minutes, P < 0.001). There were no group differences in surgical complications (2% in 3-D vs. 2.5% in conventional microscope, P = 0.28). Comparing across 4 quartiles within the 3-D group, the mean surgical time was slightly higher during the 1^st quartile (n = 25, 9.1 ± 1.9 minutes) compared to the last quartile (n = 25, 8.2 ± 1.9 minutes) (p = 0.17). Complications in the 3-D group occurred only in the initial 50% of cases. Seven (7%) cases in the 3-D group were converted to conventional binocular microscope of which 3 each were due to difficulty in depth perception and low illumination while one was due to intraoperative pupillary constriction.

Conclusion:

Phacoemulsification with the 3-D Heads up display system takes longer time but offers excellent visualization, ergonomics and safety compared to conventional microscopes. Experienced surgeons should be able to adapt easily after their first 50 surgeries.

Endoscopic vitreoretinal surgery: principles, applications and new directions

Purpose

To analyze endoscopic vitreoretinal surgery principles, applications, challenges and potential technological advances.

Background

Microendoscopic imaging permits vitreoretinal surgery for tissues that are not visible using operating microscopy ophthalmoscopy. Evolving instrumentation may overcome some limitations of current endoscopic technology.

Analysis

Transfer of the fine detail in endoscopic vitreoretinal images to extraocular video cameras is constrained currently by the caliber limitations of intraocular probes in ophthalmic surgery. Gradient index and Hopkins rod lenses provide high resolution ophthalmoscopy but restrict surgical manipulation. Fiberoptic coherent image guides offer surgical maneuverability but reduce imaging resolution. Coaxial endoscopic illumination can highlight delicate vitreoretinal structures difficult to image in chandelier or endoilluminator diffuse, side-scattered lighting. Microendoscopy’s ultra-high magnification video monitor images can reveal microscopic tissue details blurred partly by ocular media aberrations in contemporary surgical microscope ophthalmoscopy, thereby providing a lower resolution, invasive alternative to confocal fundus imaging. Endoscopic surgery is particularly useful when ocular media opacities or small pupils restrict or prevent transpupillary ophthalmoscopy. It has a growing spectrum of surgical uses that include the management of proliferative vitreoretinopathy and epiretinal membranes as well as the implantation of posterior chamber intraocular lenses and electrode arrays for intraretinal stimulation in retinitis pigmentosa. Microendoscopy’s range of applications will continue to grow with technological developments that include video microchip sensors, stereoscopic visualization, chromovitrectomy, digital image enhancement and operating room heads-up displays.

Conclusion

Microendoscopy is a robust platform for vitreoretinal surgery. Continuing clinical and technological innovation will help integrate it into the modern ophthalmic operating room of interconnected surgical microscopy, microendoscopy, vitrectomy machine and heads-up display instrumentation.

Potential Utility of a 4K Consumer Camera for Surgical Education in Ophthalmology

Purpose. We evaluated the potential utility of a cost-effective 4K consumer video system for surgical education in ophthalmology. Setting. Tokai University Hachioji Hospital, Tokyo, Japan. Design. Experimental study. Methods. The eyes that underwent cataract surgery, glaucoma surgery, vitreoretinal surgery, or oculoplastic surgery between February 2016 and April 2016 were recorded with 17.2 million pixels using a high-definition digital video camera (LUMIX DMC-GH4, Panasonic, Japan) and with 0.41 million pixels using a conventional analog video camera (MKC-501, Ikegami, Japan). Motion pictures of two cases for each surgery type were evaluated and classified as having poor, normal, or excellent visibility. Results. The 4K video system was easily installed by reading the instructions without technical expertise. The details of the surgical picture in the 4K system were highly improved over those of the conventional pictures, and the visual effects for surgical education were significantly improved. Motion pictures were stored for approximately 11 h with 512 GB SD memory. The total price of this system was USD 8000, which is a very low price compared with a commercial system. Conclusion. This 4K consumer camera was able to record and play back with high-definition surgical field visibility on the 4K monitor and is a low-cost, high-performing alternative for surgical facilities.

Endoscopic visualisation to aid deep anterior lamellar keratoplasty

AIMS

The aim of this study was to assess the value of endoscopy during deep anterior lamellar keratoplasty (DALK) by visualising the posterior cornea. This allows the surgeon to determine whether air injection had succeeded in stripping Descemet's membrane and endothelium from the posterior corneal stroma.

METHODS

Four whole globes for research were obtained from the Florida eye bank with consent. A 2 mm incision was placed at the limbus and the endoscope was introduced through this into the anterior chamber. A 26-gauge needle was introduced into the cornea with the bevel positioned as deep as possible and air injected into the corneal stroma. Air was injected until the whole cornea became opaque and repeated air injections were made even after an opaque cornea was noted. The endoscopic camera was used to visualise the posterior corneal surface during this procedure.

RESULTS

The view of the posterior corneal surface was clear and introduction of the probe did not interfere with the air dissection. In all four eyes, despite ease of air injection and diffuse corneal air infiltration, no large air bubble dissection of Descemet's membrane from adjacent stroma occurred. Instead multiple blistering of the posterior corneal surface could be seen.

CONCLUSIONS

Endoscopy provides an effective tool to visualise the posterior corneal surface during DALK, using air dissection. This technique may become a standard adjunctive procedure during DALK.

Is telesurgery a new reality? Our experience with laparoscopic and percutaneous procedures

BACKGROUND

Minimally invasive surgery offers many advantages, but its correct practice is associated with a steep learning curve. Telesurgery allows a surgeon at a remote site to guide and teach surgeons at a primary site by utilizing robotic devices, telecommunications, and video technology, thereby reducing complications.

PATIENTS AND METHODS

From September 1998 to July 2000, 17 procedures were telementored between two sites 9230 km apart: a primary operating room at the Policlinico Casilino "Tor Vergata" University of Rome and a remote site at the Johns Hopkins Medical Institutions in Baltimore. Of these procedures, 14 were laparoscopic cases: 8 spermatic vein ligations, 2 retroperitoneal renal biopsies, 3 simple nephrectomies, and 1 pyeloplasty. Three procedures were carried out to obtain percutaneous renal access. All procedures were performed with the help of two robots: the first robot, AESOP, for the orientation of the laparoscope, and the second one, PAKY, to perform the percutaneous renal access. In addition to the robotic device, the system provided four ISDN lines, a PC with dedicated software to manage the connection, audio and video connections, an external video camera with a panoramic view of the operating room, and remote control of the electrocautery and the Telestrator.

RESULTS

All the procedures were accomplished with an uneventful postoperative course. Ten operative cases were telementored successfully. In five cases, it was not possible to establish a connection to the remote site, and two procedures were converted to open surgery because of intraoperative complications. The time delay of the image transmission was <1 second.

CONCLUSION

This preliminary experience has demonstrated the feasibility of international telementoring. It could provide education to surgeons and decrease the likelihood of complications attributable to inexperience with new techniques.