Posterior capsular radial sign: a novel method to confirm anterior vitreous cortex resection in phacovitrectomy.

BACKGROUND: The main purpose of this paper is to introduce a method that can accurately locate the posterior capsule of the lens to facilitate a relatively complete resection of the anterior vitreous body. METHODS: A total of 51 patients in the experimental group and control group were enrolled in this study. Phacoemulsification combined with vitrectomy was performed in all cases. After the cataract procedure was completed in the control group, the surgeon performed a conventional anterior vitrectomy with the operative eye. In the experimental group, anterior vitrectomy was performed according to the threadiness corrugation of the posterior capsule of the lens. During the operation, with the help of triamcinolone, two surgeons confirmed the resection of the anterior vitreous cortex; the best corrected visual acuity and intraocular pressure of all patients were recorded at 1 week, 1 month and 3 months after surgery. RESULTS: Fifty patients underwent phacoemulsification combined with vitrectomy, except one patient in the experimental group who was lost to follow-up. After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. There was no significant difference in preoperative visual acuity between the two groups (t = 0.83, P = 0.25). Both groups had varying degrees of improvement in best corrected visual acuity at 1 week, 1 month and 3 months after surgery. Moreover, there was no significant difference in BCVA between the two groups at the three follow-up time points (t=-1.15, -1.65, -1.09, P = 0.53, 0.21, 0.23). After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. Incomplete resection of the anterior vitreous cortex was observed in 2 patients in each group, but there was no significant difference (χ2 = 7.81, P > 0.05). CONCLUSION: In the process of cataract surgery combined with vitrectomy, thready corrugation appears in the posterior capsule of the lens and is an important sign of its localization. Anterior vitrectomy can be accomplished safely and effectively with the help of thread-like corrugation, and the surgical effect is almost the same as that of traditional surgery. Especially suitable for beginners in vitreous surgery.

Redirection of lower eyelid eyelashes by eyelid margin splitting and anterior lamellar repositioning for patients with non-entropion trichiasis.

OBJECTIVE: To report outcomes of a surgical technique of eyelid margin splitting and anterior lamellar repositioning with lower eyelid non-entropion trichiasis. METHOD: A total of 13 patients (5 males and 8 females) with lower eyelid non-entropion trichiasis who had undergone eyelid margin splitting and anterior lamellar repositioning at Tongji Hospital from January 2018 to June 2018 were retrospectively reviewed. RESULT: All patients underwent surgery successfully, and 13 patients (23 eyes) were followed up for 9-18 months (mean 12.23±3.14 months). Symptoms were entirely relieved in all patients without the need for further surgery, and all patients were satisfied with the appearance after surgery. The lower lid margin was a flat platform with normal anatomical landmarks, and the lower eyelid eyelashes were no longer in contact with the globe. However, one patient relapsed 7 months after surgery. CONCLUSION: Patients with lower eyelid non-entropion trichiasis can be treated effectively through eyelid margin splitting and anterior lamellar repositioning with inapparent skin scarring.

Stepwise Decreasing of Vitreous Pressure by Anterior Vitrectomy: A Novel Method for Preventing Positive Vitreous Pressure During Penetrating Keratoplasty.

BACKGROUND: This study evaluates the clinical effects of the stepwise anterior vitrectomy on the prevention of positive vitreous pressure (PVP) during penetrating keratoplasty (PKP). METHODS: PKP in conjunction with stepwise anterior vitrectomy was performed on 15 eyes of 15 patients under retrobulbar anesthesia. A preset vitrectomy trocar-cannula was inserted into the vitreous cavity before PKP. During the opening of the anterior chamber, intermittent vitrectomy and corneal incision expansion were performed alternately to keep the lens or artificial intraocular lens (IOL) and iris flat until the entirety of the pathological cornea had been dissected. The main outcome measures include visual acuity, crystalline lens rise (CLR), corneal curvature and diopter, and corneal endothelial cell loss. RESULTS: All surgical procedures were performed successfully without any PVP-related intraoperative complications. The mean time of the stepwise vitrectomies was 3.1 ± 0.7 s, the duration of each vitrectomy was 8.1 ± 5.3 s, and the duration of the total surgery was 60.5 ± 5.3 min. The anterior segment reaction was mild and the shape of the pupil remained normal 1 day after surgery. The mean preoperative and mean 3-month postoperative CLR values were 0.48 ± 0.09 mm and - 0.16 ± 0.04 mm, respectively (p < 0.0001). The mean preoperative endothelial cell density in donor buttons was 2570 ± 171 cells/mm2, and the mean 6- and 12-month postoperative endothelial cell density in donor buttons was 2207 ± 127 cells/mm2 and 2000 ± 198 cells/mm2, respectively. CONCLUSIONS: The novel and stabilized PKP procedure, performed in conjunction with the stepwise anterior vitrectomy, effectively avoided the PVP during open-sky surgery. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900021227.

Phacoemulsification in eyes with corneal opacities after deep anterior lamellar keratoplasty.

To evaluate the maneuverability and efficacy of phacoemulsification and intraocular lens (IOL) implantation in eyes with corneal opacities after deep anterior lamellar keratoplasty (DALK), twelve eyes of 12 patients with mild to moderate corneal opacities after DALK and coexisting cataracts were analyzed retrospectively. Phacoemulsification and IOL implantation assisted with anterior capsule staining, as well as non-invasive optical fiber illumination, were performed on all eyes. No intraoperative or postoperative complications were noted. Mean corrected distance visual acuity (logMAR) improved from 1.24±0.17 to 0.73±0.22. Post-phaco intraocular pressure was maintained between 13 to 20 mm Hg in all cases throughout the follow-up period. Mean endothelial cell density decreased from 2258.42±205.94 to 1906.25±174.23 cells/mm2. Phacoemulsification and IOL implantation are safe and valid in eyes with mild to moderate corneal opacities after DALK and coexisting cataracts when assisted with anterior capsule staining and non-invasive optical fiber illumination.

Ex vivo construction of rabbit corneal endothelial cell sheets on a porcine descemet membrane graft.

The aim of the present study was to investigate the feasibility of a new graft construction method using rabbit corneal endothelial cells (RCECs) and a porcine descemet membrane (DM) carrier. RCECs were isolated and the experimental group was treated with Y-27632, whereas the control group were cultured in medium without Y-27632. RCEC morphology was observed using an inverted microscope, and cell proliferation and apoptosis were detected by flow cytometry. To confirm the presence of RCECs, reverse transcription-quantitative PCR was used to detect gene expression levels of Na+-K+-ATPase, aquaporin 1, collagen α2 (IV), collagen α1 (VIII) and keratin-12. Histocompatibility testing was used to detect porcine DM antigenicity. A DM-RCEC graft was constructed, and morphology was observed using alizarin red-trypan blue and haematoxylin and eosin staining. Cell membrane potential was measured to evaluate the physical function of the DM-RCEC graft. Complex graft tension was measured using a modified tension detector and compared with fresh porcine DM-endothelium complex. In vitro-cultured RCECs formed a monolayer with a polygon morphology and cobblestone-like arrangement. In vitro-cultured RCECs exhibited typical RCEC characteristics before and after transplantation. The proliferation rates of the experimental and control groups were 62.68 and 34.50%, respectively (P<0.05); the apoptosis rates of the experimental and control groups were 8.99 and 35.68%, respectively (P<0.05). There was no antigenicity observed with the porcine DM. The action potential amplitude of the experimental and control groups was over -80 mV, reflecting normal RCEC physiological function. The tension measurements of the experimental and control groups were 20.0248±1.048 and 20.5013±0.657 g, respectively (P>0.05). Taken together, the results of the present study demonstrated that Y-27632 enhanced RCEC proliferation. In addition, the findings revealed the successful ex vivo construction of a RCEC sheet on a porcine DM graft.

Individualized penetrating keratoplasty using edge-trimmed glycerol-preserved donor corneas for perforated corneal ulcers.

PURPOSE: To report a surgical technique and the surgical outcomes of individualized penetrating keratoplasty (PK) using edge-trimmed glycerol-preserved donor corneas for perforated corneal ulcers. METHODS: Fourteen perforated eyes from 14 patients who underwent individualized PK using edge-trimmed glycerol-preserved donor corneas, were included in the retrospective study. The perforations were mainly 1-2 mm in size except for one that was 2.5 × 4 mm. Three patients were treated with PK; one patient was treated with PK and a conjunctival flap; ten patients who had large ulcer areas were treated with PK combined with lamellar keratoplasty (LK). Donor corneas were preserved in sterile pure glycerol at - 80 °C. Corneal grafts were specially edge-trimmed to match the perforation, and then sutured onto the recipient bed avoiding the visual axis. RESULTS: All 14 patients recovered anatomical integrity without reinfections of the treated eyes. All patients had improved graft transparency and uncorrected visual acuity after surgery. Among them, four patients suffered from short-term postoperative complications and recovered quickly; four patients suffered from long-term postoperative complications, of them, one was performed further treatment. CONCLUSION: After individualized PK using glycerol-preserved donor corneas, all perforated corneal ulcers were stably controlled by the end of the follow-up period. This modified surgical technique can be a potential treatment choice for patients with perforated corneal ulcers.

BMP4 is required for the initial expression of MITF in melanocyte precursor differentiation from embryonic stem cells.

Although the differentiation of melanoblasts to melanocytes is known to depend on many distinct factors, it is still poorly understood which factors lead to the induction of melanoblasts. To determine which factors might induce melanoblasts, we examined a set of candidate factors for their ability to induce expression of MITF, a master regulator of melanoblast development, in an ES cell-based melanocyte differentiation system. It appears that BMP4 is capable of inducing MITF expression in stem cells. In contrast, a number of other factors normally implicated in the development of the melanocyte lineage, including WNT1, WNT3a, SCF, EDN3, IGF1, PDGF, and RA, cannot induce MITF expression. Nevertheless, BMP4 alone does not allow MITF-expressing precursors to become differentiated melanocytes, but the addition of EDN3 further promotes differentiation of the precursors into mature melanocytes. Our results support a model in which BMP4 induces MITF expression in pluripotent stem cells and EDN3 subsequently promotes differentiation of these MITF expressing cells along the melanocyte lineage.