Corneal graft melting: a systematic review.

Corneal graft melting is a severe complication of keratoplasty. This review is to summarize the incidence, the pathogenesis, the risk factors, the prognosis and the prevention of corneal graft melting after keratoplasty. We systematically searched PubMed, Web of Science and WanFang database to retrieve potentially eligible articles about relevant clinical reports and animal experiments. We read the full texts to identify eligible articles. The selection of studies and data extraction were performed independently by two reviewers. In conclusion, the pathogenesis of corneal graft melting is complicated, and many risk factors are closely related to corneal graft melting. Analysis of pathogenesis and risk factors of corneal graft melting can facilitate the development of targeted therapies to better guide clinical practice.

Baicalin Alleviates Age-Related Macular Degeneration via miR-223/NLRP3-Regulated Pyroptosis.

BACKGROUND: Age-related macular degeneration (AMD), a major eye degenerative disease, ultimately causes irreversible vision loss. Baicalin was identified to attenuate laser-induced chorodial neovascularization, indicating a therapeutic role in AMD. However, the exact mechanisms for baicalin in AMD remain unknown. METHODS: MTT assay was performed to access the suitable concentration of baicalin or Aß for treating ARPE-19 cells. CCK-8, morphology, and flow cytometry analysis were performed to evaluate cell viability and pyroptosis of baicalin in Aß-envoked ARPE-19 cells. Quantitative real-time polymerase chain reaction and western blot analysis were subjected to measure the correlation between miR-223 and NLRP3. Luciferase reporter assay was performed to determine their direct relationship. Western blot analysis was subjected to determine pyroptosis-related proteins. RESULTS: Baicalin inhibited Aß-envoked pyroptosis in ARPE-19 cells. Mechanistically, baicalin significantly induced upregulation of miR-223 and downregulation of NLRP3, thus suppressing pyroptosis triggered by NLRP3 inflammasome signaling, yet such beneficial effects were reversed by miR-223 knockdown. Additionally, MCC950, a NLRP3 inhibitor, restored anti-pyroptosis activity of baicalin under miR-223 silencing. CONCLUSION: Baicalin alleviates intracellular pyroptosis and viability damage resulted from Aß inducement in human retinal pigment epithelium cells via negative crosstalk of miR-223/NLRP3 inflammasome signaling, indicating that baicalin may be considered as a potential candidate for AMD therapy.

Evaluation of artificial tears on cornea epithelium healing.

AIM: To observe the efficacy of different artificial eye drops on corneal epithelium healing in rabbit. METHODS: Thirty-five rabbits with 6 mm diameter central corneal epithelium removed were randomly assigned to six groups: 0.9% normal saline (NS) group, 0.1% hyaluronate (HA) group, 0.3% HA group, Tears Naturale Free® (TNF) group, 0.4% polyethylene glycol (PEG) group, 0.5% carboxymethyl cellulose (CMC) group and blank control group. Treatments were administered topically four times daily. Corneal epithelium healing was evaluated by the percentage reduction in wound area at 24, 36, 48, 60, and 72h after removal of the corneal epithelium. Cornea re-epithelialization was also assessed by histological analysis and electron microscopy. RESULTS: All corneal wounds completely re-epithelialized in less than 72h. The average re-epithelialization time was 47.61±4.25h in the 0.3% HA group and 49.72±1.05h in the 0.9% NS group, followed by 0.1% HA, TNF, 0.4% PEG, 0.5% CMC, and lastly by the control group. Compared to the control group, there were significant differences among 0.3% HA, 0.9% NS, PEG, and TNF (P<0.05) groups. At the first 24h, re-epithelialization at the 0.3% HA, TNF, and 0.9% NS treatment groups were significantly faster than the other groups. At 48h post-wounding, corneal epithelium is nearly completing re-epithelialization at 0.3% HA and 0.9% NS treatment groups. Electron microscopy revealed that there were a large number of vacuoles in the cells of the 0.9% NS group at 72h. CONCLUSION: Artificial tears promote corneal re-epithelium varied in the efficacy. Obviously, all artificial eye drops better than blank group. In the process of corneal healing, corneal epithelium cells suffered from hypoxia caused by NS.

Use of the Crawford tube for symptomatic epiphora without nasolacrimal obstruction.

AIM: To evaluate the effectiveness of the Crawford tube in treating symptomatic epiphora without nasolacrimal obstruction. METHODS: A protocol was adopted for the management of symptomatic epiphora without nasolacrimal obstruction. Patients who suffered symptomatic epiphora without nasolacrimal obstruction in both eyes were included in the study. One eye was treated with Crawford tube intubation and the other eye was treated with medication therapy. Degree of watering, patient satisfaction, and symptomatic improvement were carefully evaluated by one of the authors at the end of the follow-up period, after Crawford tube removal, to ascertain functional results. RESULTS: Thirty-seven adult patients (37 eyes) underwent Crawford tube intubation for functional epiphora. The mean follow-up time after removal of the tube was 14.8±4.8mo. The procedure was an overall success in 28 eyes (75.7%), with symptoms improving significantly. Two eyes (5.4%) were relieved of indoor epiphora, two (5.4%) had minimal epiphora outdoors, but only with wind or cold, and five (13.5%) continued to experience tearing both indoors and outdoors. Thirty of the patients (81%) expressed satisfaction with the procedure. CONCLUSION: Crawford tube insertion is an effective, safe, simple, and relatively noninvasive treatment strategy for functional lacrimal system obstruction.

Corneal injury and its protection using hydro-gel patch during general anesthesia.

AIM: To evaluate corneal injury during general anesthesia and analyze the protective effect of medical hydro-gel eye patch in clinics. METHODS: Seventy-six patients with 152 eyes undergoing general anesthesia were included. None had positive corneal fluorescein staining before surgery. Both eyes of each patient were analyzed, with one randomly allocated to receive medical hydro-gel eye patch, and the other to receive common adhesive tape as a control. Corneal injuries were evaluated by scoring fluorescein staining under a hand-held slit lamp immediately after surgery in postanesthesia care unit and 24h thereafter. Patients' discomforts were also evaluated. RESULTS: Twelve eyes (15.8%) in the hydro-gel patch group and 30 eyes (39.5%) in the adhesive tape group showed corneal injury immediately after surgery. The eyes protected with hydro-gel patch showed statistically less corneal fluorescein staining than the control group. Four eyes in hydro-gel patch group and 6 eyes in adhesive tape group suffered discomfort immediately after surgery without intergroup difference and all discomforts disappeared after 24h (P=0.257). No side effect was observed in hydro-gel patch group, while 5 eyes had brow avulsion and 2 got skin itching in adhesive tape group. CONCLUSION: Corneal injury complication was more frequent than we thought following general anesthesia. The medical hydro-gel eye patch can protect the occurrence of corneal injury following general anesthesia.

[Clinical features of 233 cases of keratoconus].

OBJECTIVE: To analyze clinical features of keratoconus. METHODS: The case history of keratoconus patients who underwent penetrating keratoplasty, epikeratophakia or deep lamellar keratoplasty in our hospital during January 1993 to March 2002 was reviewed, and inquiry form was sent to those who without complete data. Patients were followed during January 2000 to March 2002. Two hundred and thirty three cases of keratoconus were enrolled in this study with 216 males and 17 females. Patient's family history, systemic complications, refractive status, progress of disease, eye axial length and anterior chamber depth were recorded. RESULTS: The clinical natural history of these patients followed the model of "myopia-astigmatism-poor spectacle correction-acute corneal hydrops or stromal scar". The presenting age of myopia ranged from 6 to 29 years, with a mean age of 13.8 years, 10.1% (22/219) of the patients were younger than 10 years, 67.1% (147/219) were between 11 and 15 years. The interval time between emerging myopia and poor spectacle correction (best corrected visual acuity less than 20/200) was ranged from 1 to 20 years, of which 85.2% (161/189) were shorter than 6 years. Twenty percent (47/233) of the patients had acute corneal hydrops in one eye at the age of 12 to 31 years, and 4.3% of them (2/47) resulted in corneal perforation. Thirty-four patients had corneal stromal scars 1 to 13 years after keratoconus developed, and 94.1% of them (32/34) were within 8 years. Topography examination demonstrated a tendency of the cone base position progress: first, paracentral-enlargement following dominant astigmatism axis, then, enlargement along smaller astigmatism axis, and finally, the cone base moving centrally. The eye axial length averaged at (25.9 +/- 1.4) mm, the depth of anterior chamber (AC) were (4.3 +/- 0.3) mm, 89.7% (279/311) eyes had an axial length longer than 24 mm. All cases had an asymmetry clinical progress course. Two cases had Down syndrome, 2 with intelligence defect. No family history was noted in this study. CONCLUSIONS: Keratoconus in Han nationality of Shandong Province has a relatively earlier age onset. These eyes tend to have a deeper AC with higher incidence of longer axial length.

[Combined penetrating keratoplasty with keratolimbal allograft transplantation in the treatment of severe corneal burns].

OBJECTIVE: To study the clinical results of combined penetrating keratoplasty with keratolimbal allograft transplantation in the treatment of severe corneal burns. METHODS: The present study consisted of 35 eyes (34 patients) with full thickness corneal opacities and extensive corneal conjunctivalization after severe corneal burns. The duration between the injury and the time of presentation ranged from four months to 23 years. Group A: Combined penetrating keratoplasty (PK) with annular keratolimbal allograft transplantation (KLAT) was performed in 19 eyes (18 patients). Group B: Total PK with a scleral rim was performed in 16 eyes (16 patients). Post-operative visual acuity, intraocular pressure, graft rejection and complications were monitored. The average follow up time was 24 (range from 15 to 28) months. RESULTS: (1) Vision: The number of eyes that obtained best corrected visual acuity > 0.05 was 18 eyes (95%) in group A and 14 eyes (84%) in group B at 6 months postoperatively (P = 0.582); 16 eyes (88%) in group A and 6 eyes (38%) in group B at 12 months (P = 0.006); 12 eyes (63%) in group A and 3 (7%) in group B at 24 months (P = 0.016). (2) Graft rejection: Nine allografts (47%) in group A and 8 grafts (50%) in group B developed limbal stem cell rejection (P = 1.000); 6 allografts (32%) in group A and 11 allografts (69%) in group B developed endothelium rejection (P = 0.044). The difference of endothelium rejection rate between group A and B was not significant at different times postoperatively. (3)COMPLICATIONS: Corneal epithelium defect occurred in 2 eyes (11%) in group A and 7 (44%) eyes in group B (P = 0.049); hyphema occurred in 2 eyes (11%) in group A and 8 eyes (50%) in group B (P = 0.022); hypotony occurred in 1 eye (5%) in group A and 6 eyes (38%) in group B (P = 0.032). CONCLUSIONS: PK combined with KLAT is an effective treatment for severe corneal burns at a late stage irrespective of the etiology. This procedure can restore visual function in severely damaged eyes. Patients treated with PK combined with KLAT show less complication and better prognosis as compared with patients treated with total PK with a scleral rim.

[A retrospective medical history analysis of the patients with severe fungal keratitis].

OBJECTIVE: To investigate the cause of delayed diagnosis and treatment in severe fungal keratitis. METHODS: Retrospective analysis of the treatment history was performed in patients with severe fungal keratitis which attended to our hospital during 2000 to 2001. The main parameters evaluated were nature of access with the health care services, examinations undertaken, initiated treatment, and the time interval between presentation to each medical contact and to our center. Finally, the management undertaken at our center was evaluated. RESULTS: 69 patients (eyes) were enrolled into this investigation, of which 86% (59/69) was local residents in Shandong province, 93% (64/69) was farmer. Penetrating keratoplasty (PKP) were performed for 63 cases with a transplantation of donor cornea > 8.0 mm. However, 6 eyes were enucleated because of the severe endophthalmitis. Most of patients sought medical care following a same procedure: village and towns medical service, county hospital, city medical center. The time interval between the first medical contact and presentation to our center was 22.9 days on average. 78% (54/69) patients attended to county hospitals, only 24% (13/54) patients got correct diagnosis of fungal keratitis. Smear examination had been undertaken only in 22% (12/54) of cases, the positive rate was 50%. In 30 patients who initially contact to city medical centers, 63% (19/30) was diagnosed as fungal keratitis, 73% (22/30) was given smear examination with positive result of 73% (16/22). The positive rate of corneal scraping for fungus was 93% (64/69). 46% (35/69) patients were prescribed antifungal agents of fluoconazole. CONCLUSION: Several factors, including ignoring traumatic history and basic examination techniques, lacking of effective ophthalmic antifungal agents, cornea donor, without qualified ophthalmologists, lead to inappropriate management in fungal keratitis.