Glasses-Assisted 3D Display System-Guided Descemet Membrane Endothelial Keratoplasty Tissue Preparation

3D Heads-up digital filters for cataract surgery and corneal transplantation

PURPOSE

To describe the advantages of Ngenuity 3D digital filters for enhancing visualization during cataract and corneal transplant surgery.

METHODS

All surgeries were performed by the same experienced surgeon (L.M.) using the Ngenuity 3D heads-up visualization system connected to a microscope. Images were simultaneously captured with and without the filter in each of the following phases: endothelial evaluation, capsulorhexis, capsule rupture, vitreous leak, cortex removal, visco removal, corneal suture, descemetorhexis, DMEK graft preparation and insertion.

RESULTS

In cataract surgery, green and monochrome filters facilitate capsulorhexis in difficult situations by highlighting the anterior capsule and can improve visualization of a posterior capsular tear. The enhanced contrast of the monochrome filter is also useful for cortex and viscoelastic removal. In corneal surgery, the green filter highlights the rim of the DMEK graft during tissue preparation, the yellow filter enhances the contrast of the stained DMEK graft in the anterior chamber, the monochrome filter simplifies descemetorhexis by improving visualization of the Descemet/endothelial layer and allows a better view in red saturated images while performing sutures.

CONCLUSIONS

Ngenuity digital filters have the potential to enhance tissue visualization during cataract and corneal surgeries, especially in poor visibility conditions.

Descemet Membrane Endothelial Keratoplasty and Descemet Stripping Only Using a 3D Visualization System

(1) Purpose: The aim was to analyze the outcomes of Descemet's membrane endothelial keratoplasty (DMEK) and Descemet stripping only (DSO) surgeries using a glasses-assisted NGENUITY® 3D visualization system (Alcon Laboratories, Fort Worth, TX, USA). (2) Methods: Five consecutive cases of DMEK surgery and four consecutive cases of DSO were performed using the NGENUITY® system in this prospective study carried out at the Arruzafa Hospital, Córdoba, Spain. Only one eye from each patient received surgery. Best corrected distance visual acuity (CDVA) using EDTRS charts, central corneal thickness using the Casia II optical coherence tomograph (Tomey Co., Nagoya, Japan), and endothelial cell count using the Tomey EM-4000 (Tomey Co., Nagoya, Japan) for DMEK cases or the Nidek CEM-530 (Nidek Co., Ltd., Gamagori, Japan) specular microscopes for DSO cases were recorded preoperatively and at 1 and 3 months postsurgery. (3) Results: DMEK cases included one male and four female subjects, with a mean age of 73.6 ± 9.5 years. Average improvement in CDVA 3 months after surgery was 0.46 ± 0.16 decimal. Average change in cell count between 1 and 3 months postsurgery was 360.75 ± 289.38 cells/mm2. DSO cases included four female subjects, with a mean age of 64.2 ± 9.7 years. The average improvement in CDVA 3 months after surgery was 0.09 ± 0.17 decimal. All cases also had phacoemulsification carried out. He average change in cell count between 1 and 3 months after surgery was 460 ± 515.69 cells/mm2. There were no associated complications during surgery or the follow-up period in any of the cases. (4) Conclusions: In addition to the known benefits of the use of a 3D visualization system during surgery, the present study shows that the system can be successfully used in both DMEK and DSO procedures with a very short learning curve for the surgeon.

3D Visualization System in Descemet Membrane Endothelial Keratoplasty (DMEK): A Six-Month Comparison with Conventional Microscope

Background: To compare the efficacy and safety of Descemet membrane endothelial keratoplasty (DMEK) surgery using the three-dimensional (3D) display system NGENUITY to DMEK surgery performed with the traditional microscope (TM) in patients affected by Fuchs Endothelial Corneal Disease (FECD). Methods: Retrospective comparative study of 40 pseudophakic eyes of 40 patients affected by FECD who underwent DMEK surgery. Twenty patients (3D group) were operated on using the 3D display system and 20 patients (TM group) were operated on using the traditional microscope. Best spectacle corrected visual acuity (BSCVA), central corneal thickness (CCT), endothelial cell density (ECD) and corneal densitometry (CD) values were documented before and at 1, 3 and 6 months after DMEK. Intra- and postoperative complications were recorded. Results: The baseline assessments did not differ between the two groups (p > 0.05). Global surgical time and time to perform descemetorhexis were significantly lower in the TM group (p = 0.04 and p = 0.02, respectively). BSCVA, CCT, ECD and CD values did not differ significantly in the two groups at all follow-ups (p > 0.05). Complication rate was similar between the two groups. Conclusion: Three-dimensional display systems can be securely employed in DMEK surgery considering the satisfactory clinical outcomes, including Scheimpflug CD. Nevertheless, the slightly longer surgical time of the 3D DMEKs may lead to surgeons’ hesitancy. The main advantages of the heads-up approach may be the improved ergonomic comfort during surgery and the utility of assistants in surgical training.