An experimental and clinical study on the initial experiences of Brazilian vitreoretinal surgeons with heads-up...

To evaluate the initial experiences of several vitreoretinal surgeons in Brazil, both experienced and beginners, with a three-dimensional (3D) system, and to report the advantages and disadvantages of this technology. We also report surgical manipulations performed using the heads-up method in porcine eyes. For full-thickness idiopathic macular holes (MHs), we analyzed the times required for pars plana vitrectomy (PPV) and internal limiting membrane (ILM) rhexis by using traditional microscopy and 3D system, and to evaluate anatomical surgical results.

During experimental vitreoretinal surgery on porcine eyes, two retinal surgeons applied the heads-up method. In clinical surgery, 14 retinal surgeons performed almost all types of vitreoretinal surgeries in association with facectomy, Ahmed glaucoma valve implant, or minimally invasive glaucoma surgery using an iStent®. The Ngenuity® 3D Visualization System was digitally integrated with intraoperative optical coherence tomography, the Verion™ Image-Guided System, and an endoscope (with a modified GoPro® camera). To compare the 3D system with traditional microscopy, ergonomics, educational value, image sharpness, depth perception, field of view, advantages and disadvantages, and technical feasibility were assessed using a questionnaire. One year later, the 14 surgeons answered the same questionnaire again, in order to assess whether they became more comfortable or not with 3D. For treating MHs, four surgeons (surgeon 1, fellows 1, 2, 3) performed the total of 40 surgeries. Each one performed 10 surgeries (5 with traditional microscopy and 5 with 3D visualization). The completion time for PPV and ILM rhexis were determined by using both methods.

In porcine eyes, disabling the color channels allowed better visualization of the ILM, either with Brilliant Blue G (BBG), indocyanine green chorioangiography (ICG), or açai dye; transillumination through the sclera was also better without a color channel, but visualization of the peripheral vitreous was better with a blue channel. Regarding clinical experience, the questionnaire responses showed that the respondents generally favored the heads-up method compared with traditional microscopy (p < 0.05); however, despite a slightly higher average score, the 3D system was not statistically significantly preferred in terms of technical feasibility (p = 0.1814). Answering again the same questionnaire 1 year later, the 14 surgeons felt more comfortable with 3D (p < 0.05). The type of surgery benefitting most from the 3D system was peeling of the ILM or epiretinal membrane (p < 0.001), and that receiving the least benefit was anterior segment surgery (p < 0.001). In addition, surgeons did not report benefits of color channels, preferring to disable it (p < 0.001). Comparisons between the average time for full PPV and ILM rhexis by using the two methods were non-significant, neither in each individual case of 3D surgery for each surgeon. Surgeon 1 had always been faster than his fellows. Thirty-six (90%) full-thickness MHs were successfully closed with one surgery.

The 3D system was preferred to traditional microscopy. The 3D system was especially helpful for certain specific types of surgeries and served as an educational tool, having reduced illumination and allowing precise focusing. Concerning MH surgery, heads-up method was similar to traditional microscopy regarding length of time and anatomical surgical results. As a digital platform, it will be amenable to constant upgrades and may ultimately become the new standard for ophthalmic surgery.