Color enhancement and achromatization to increase the visibility of indocyanine green-stained internal limiting membrane during digitally assisted vitreoretinal surgery.

PURPOSE: To investigate the impact of using digital assisted vitrectomy (DAV) for color enhancement in color channel and achromatization in color profile on the visibility of indocyanine green (ICG)-stained internal limiting membrane (ILM). STUDY DESIGN: Retrospective observational study. METHODS: Twenty eyes from 20 patients (7 men, 13 women) who underwent 27-gauge pars plana vitrectomy for epiretinal membrane removal were included. The presettings of five different imaging modes of the NGENUITY® 3D visualization system (Alcon laboratories, Inc.), were adjusted, and intraoperative images of ILM removal were captured under each presetting. The color contrast ratios (CCR) between the ICG-stained ILM area and peeled ILM area were compared across presettings objectively. Subjective visibility of ILM in each patient for different presettings was ranked using a Likert scale and evaluated by five examiners. Data on sex, age, preoperative and postoperative best-corrected visual acuity (BCVA), preoperative and postoperative intraocular pressure (IOP), and postoperative complications were analyzed. RESULTS: Compared to other presettings the best CCR was achieved by adjusting the color channel to enhance red and by modifying the color profile to create a monochrome image (P<0.01). The same presetting resulted in a highest subjective visibility (P<0.01). Mean preoperative BCVA and 6-month postoperative BCVA (logMAR) were 0.11±0.18 and 0.05±0.19, respectively (p=0.24). Mean preoperative IOP and 6-month postoperative IOP were 13.8±2.8 mmHg and 13.3±3.4 mmHg, respectively (p=0.51). No apparent intra- and post-operative complications were observed. CONCLUSION: Color enhancement and achromatization using DAV may offer potential advantages to enhance the visibility of ICG-stained ILM.

Usefulness of intraoperative optical coherence tomography to minimize the intraocular lens tilt during the intrascleral fixation: a clinical and experimental evaluation.

To report the usefulness of intraoperative real-time adjustment of intraocular lens (IOL) tilt during the intrascleral fixation with intraoperative optical coherence tomography (iOCT) as a clinical evaluation and investigate the factors contributing to IOL tilt using iOCT as an experimental evaluation. Retrospective cohort study and experimental research. As a clinical evaluation, the medical records of 43 eyes of 41 patients who underwent intrascleral IOL fixation combined with real-time iOCT observation were retrospectively reviewed. As an experimental evaluation, in order to investigate the factors contributing to IOL tilt, the four experiments were performed using iOCT. The mean IOL tilt angle (°) at the end of surgery and 3 months after surgery were 1.81 ± 1.15 and 2.10 ± 1.66, respectively (p = 0.46). No apparent intra- or postoperative complications occurred during the follow-up period. The experimental evaluation indicated that the IOL tilt was influenced by the insertion angle of the haptic in the vertical direction. The mean IOL tilt angle (°) was 1.94 ± 0.09, 4.67 ± 0.11, 8.90 ± 0.11, and 15.78 ± 0.85 when the insertion angle of the haptic was 0°, 10°, 27.5°, and 45° in the vertical direction, respectively (p < 0.01). Clinical and experimental IOL tilt assessment using iOCT is interactively useful for better quality surgery and better postoperative outcome.

Removal of Sub-Internal Limiting Membrane Hemorrhage Secondary to Retinal Arterial Macroaneurysm Rupture: Internal Limiting Membrane Non-Peeling Technique.

The appropriate surgical technique to improve the closure rate of perioperative full-thickness macular hole (FTMH) secondary to submacular hemorrhage (SMH) with sub-internal limiting membrane (ILM) hemorrhage caused by retinal arterial macroaneurysm (RAM) rupture remains an unsolved clinical problem. Several ILM transplantation techniques have been attempted, but these are challenging. Our new technique can remove sub-ILM hemorrhage with the central fovea ILM intact, without peeling the ILM. The medical records of three eyes from three patients with SMH and sub-ILM hemorrhage secondary to RAM rupture were retrospectively reviewed. During the surgery, a small ILM fissure was made outside the central fovea with ILM forceps, and sub-ILM hemorrhage was washed out through it by manually spraying balanced salt solution. Sub-ILM hemorrhage removal was achieved successfully in all eyes, with no occurrences of FTMH or other complications. Best-corrected decimal visual acuity improved from 0.05 (Snellen equivalent (SE), 20/400), 0.05 (SE, 20/400), and 0.05 (SE, 20/400) preoperatively to 0.3 (SE, 20/63), 0.4 (SE, 20/50), and 0.15 (SE, 20/125) at 3 months postoperatively, respectively. This new technique may help keep the foveal ILM intact and prevent perioperative FTMH formation.

INTRAOPERATIVE OPTICAL COHERENCE TOMOGRAPHY FOR REAL-TIME VISUALIZATION OF THE POSITIONAL RELATIONSHIP BETWEEN BUCKLING MATERIAL AND RETINAL BREAKS DURING SCLERAL BUCKLING FOR RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To report the usefulness of a new surgical method using intraoperative optical coherence tomography that can more accurately place the buckling material for scleral buckling using a noncontact wide-angle viewing system with a cannula-based chandelier endoilluminator for the treatment of rhegmatogenous retinal detachment. METHODS: The medical records of 12 eyes of 11 patients with rhegmatogenous retinal detachment treated with scleral buckling combined with real-time intraoperative optical coherence tomography observation were retrospectively reviewed. RESULTS: Real-time observations of the positional relationship between the protrusion of buckling material and retinal breaks with intraoperative optical coherence tomography revealed that retinal breaks were not properly placed on the protrusion of the buckling material in five eyes, requiring the intraoperative repositioning of the buckling material. Eventually, the scleral buckling combined with real-time intraoperative optical coherence tomography observation yielded the initial anatomical success rates of 100% without noteworthy intraoperative or postoperative complications. CONCLUSION: This procedure is a novel approach that enables safer and more accurate placement of the buckling material and may contribute to improving the outcomes of scleral buckling in the future.

Removal of Subfoveal Massive Hard Exudates through an Intentional Macular Hole in Patients with Diabetic Maculopathy: A Report of Three Cases.

Recently, good postoperative visual acuity has been reported using surgical removal of hard exudates (HEs) through an intentional macular hole (iMH). We report 3 cases of subfoveal HE secondary to diabetic maculopathy (DM) treated with HE removal via an iMH. Pars plana vitrectomy (PPV) was performed in three eyes of 3 patients with subfoveal HE secondary to DM. In all eyes, after PPV, internal limiting membrane (ILM) peeling of the lower half was performed within the range of papilla diameter 2 centered on the fovea, leaving the upper half for subsequent inverted ILM flap technique. Then, by grabbing the inner layer of the fovea using ILM forceps, an iMH was created. The HE was then flushed from the iMH with a balanced salt solution as much as possible. Finally, the inverted ILM flap technique was performed using the upper half of the ILM that was left during the previous maneuver. At the end of the surgery, the eyes were flushed with 50 mL of 20% sulfur hexafluoride (SF6) after the fluid-air exchange of the vitreous cavity. After surgery, HE was adequately removed, iMH was completely closed, and visual acuity improved in all eyes. This surgical procedure did not cause a central scotoma but rather improved the central sensitivity of the visual field in all eyes. No serious surgery-related complications occurred. In conclusion, HE removal via an iMH hole can be one of the treatment options for patients with subfoveal HE secondary to DM.

Comparison of Two Cases of Foveal Laceration Caused by a Mower.

We report and compare 2 cases of open globe injury with foveal damage incurred while mowing. Case 1 is a healthy 67-year-old man presenting with an intraocular metallic foreign body and eye pain in his right eye after using a mower. The foreign body perforated the cornea's inferior area and damaged the foveal centralis, leading to central scotoma and decreased visual acuity. 27G pars plana vitrectomy was performed, and the final corrected decimal visual acuity was 0.1, but the visual field was preserved, except for the central scotoma. Case 2 is a healthy 50-year-old man presenting open globe injury with an intraocular metallic foreign body while using a mower. The foreign body damaged the fovea and triggered extensive retinal detachment. One month after surgery, proliferative vitreoretinopathy occurred, requiring additional surgery. The final corrected decimal visual acuity dropped to 0.05, resulting in an extensive visual field defect. Both cases of eye trauma were caused by mower injury, but the visual function outcomes differed with the size of the foreign body and the injury severity at the time of onset. Mower eye trauma is preventable, and efforts to educate users on safety measures are needed.

Role of macrophage migration inhibitory factor (MIF) in the effects of oxidative stress on human retinal pigment epithelial cells.

Proliferative vitreoretinopathy (PVR) is the major cause of treatment failure in individuals who undergo surgery for retinal detachment. The epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE) cells contributes to the pathogenesis of PVR. Oxidative stress is thought to play a role in the progression of retinal diseases including PVR. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line. We found that H2 O2 induced the contraction of RPE cells in a three-dimensional collagen gel. Analysis of a cytokine array revealed that H2 O2 specifically increased the release of macrophage migration inhibitory factor (MIF) from RPE cells. Reverse transcription-polymerase chain reaction and immunoblot analyses showed that H2 O2 increased the expression of MIF in RPE cells. Immunoblot and immunofluorescence analyses revealed that H2 O2 upregulated the expression of α-SMA and vimentin and downregulated that of ZO-1 and N-cadherin. Consistent with these observations, the transepithelial electrical resistance of cell was reduced by exposure to H2 O2 . The effects of oxidative stress on EMT-related and junctional protein expression as well as on transepithelial electrical resistance were inhibited by antibodies to MIF, but they were not mimicked by treatment with recombinant MIF. Finally, analysis with a profiling array for mitogen-activated protein kinase signalling revealed that H2 O2 specifically induced the phosphorylation of p38 mitogen-activated protein kinase. Our results thus suggest that MIF may play a role in induction of the EMT and related processes by oxidative stress in RPE cells and that it might thereby contribute to the pathogenesis of PVR. Proliferative vitreoretinopathy is a major complication of rhegmatogenous retinal detachment, and both oxidative stress and induction of the EMT in RPE cells are thought to contribute to the pathogenesis of this condition. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line ARPE19. Our results thus implicate MIF in induction of the EMT and related processes by oxidative stress in RPE cells and the regulated expression of EMT markers. They further suggest that MIF may play an important role in the pathogenesis of PVR.