A surgical alternative of fusiform penetrating keratoplasty for the management of severe infectious keratitis

AIM:To describe the surgical procedure of fusiform penetrating keratoplasty(FPK)using multiple trephines of different sizes for treating patients with severe infectious keratitis.METHODS:Fourteen eyes underwent FPK,and 15 eyes received conventional penetrating keratoplasty(PK)were included in the study.The best-corrected visual acuity(BCVA),refractive outcomes,endothelial cell density,and postoperative complications were recorded.RESULTS:The FPK group was followed for an average of 15.3±2.1mo,whereas the PK group was followed for 16.1±1.9mo.The corneal ulcers were elliptical-shaped in all 14 eyes in the FPK group.The mean BCVA(logMAR,0.26±0.13)showed no statistically significant differences from that in the PK group(logMAR,0.21±0.12,P>0.05)at 1y after surgery.But the mean curvature,mean astigmatism,and mean spherical equivalent in the FPK group were lower than those in the PK group(P<0.05).Peripheral anterior synechia was observed in one patient in the FPK group,whereas 6 patients in the PK group.Suture loosening and neovascularization were observed in 4 and 5 eyes in the PK group,respectively.No graft immune rejection or elevation of intraocular pressure was observed in the two groups.CONCLUSION:For patients with elliptical-shaped corneas or corneal ulcers,FPK can avoid disrupting of corneal limbus,reduce the risk of postoperative complications,and can result in satisfactory visual quality.

Epidemiological,clinical and laboratory findings of infectious keratitis at Mansoura Ophthalmic Center,Egypt

AIM： To analyze the epidemiological, clinical and laboratory findings of infectious keratitis.METHODS： A retrospective study on cases of infective keratitis, attended our institution from Mar. 2013 to Feb. 2015, was done at Mansoura Ophthalmic Center, Egypt. Corneal scrapings were performed and processed for direct microscopy and culture in appropriate media using standard laboratory protocols.RESULTS： Out of 245 patients enrolled for study, 247 corneal scrapings were obtained. Ocular trauma was the most common predisposing factor （51.4%）, followed by diabetes mellitus （15.1%）. Cultures were positive in 110 scraping samples （44.5%）： 45.5% samples had pure fungal infection, 40% had pure bacterial infections and 10% had mixed fungal and bacterial growths. Acanthamoeba was detected in 5 （4.5%） samples. The most common fungal pathogen was Aspergillus spp. （41%）. The most common bacterial isolates were Staphylococcus aureus （38.2%） and Pseudomonas aeruginosa （21.8%）.CONCLUSION： Incidence of fungal keratitis is high in our region. Therapeutic approach can initially be based on clinical features and sensitivity/resistance patterns. Microbiological research should direct the antimicrobial treatment. Antibiotic resistance to fluoroquinolones and aminoglycosides is an important consideration.

Infectious keratitis in Vietnam:etiology,organisms,and management at Vietnam National Eye Hospital

AIM:To report the etiologies,risk factors,treatments,and outcomes of infectious keratitis(IK)at a major Vietnamese eye hospital.METHODS:This is a retrospective review of all cases of IK at Vietnam National Eye Hospital(VNEH)in Hanoi,Vietnam.Medical histories,demographics,clinical features,microbiological results,and treatment outcomes were reviewed.RESULTS:IK was diagnosed in 1974 eyes of 1952 patients,with ocular trauma being the greatest risk factor for IK(34.2%),frequently resulting from an agriculturerelated injur y(53.3%).The mean duration between symptom onset and presentation to VNEH was 19.3±14.4 d,and 98.7%of patients had been treated with topical antibiotic and/or antifungal agents prior to evaluation at VNEH.Based on smear results of 1706 samples,the most common organisms identified were bacteria(n=1107,64.9%)and fungi(n=1092,64.0%),with identification of both bacteria and fungi in 614(36.0%)eyes.Fifty-five of 374 bacterial cultures(14.7%)and 426 of 838 fungal cultures(50.8%)were positive,with the most commonly cultured pathogens being Pseudomonas aeruginosa,Streptococcus pneumonia,Fusarium spp.,and Aspergillus spp.Corneal perforation and descemetocele developed in 391(19.8%)and 93(4.7%)eyes,respectively.Medical treatment was successful in resolving IK in 50.4%eyes,while 337(17.1%)eyes underwent penetrating or anterior lamellar keratoplasty.Evisceration was performed in 7.1%of eyes,most commonly in the setting of fungal keratitis.CONCLUSION:Ocular trauma is a major risk factor for IK in Vietnam,which is diagnosed in almost 400 patients each year at VNEH.Given this,and as approximately one quarter of the eyes that develop IK require corneal transplantation or evisceration,greater emphasis should be placed on the development of prevention and treatment programs for IK in Vietnam.

PACK-CXL vs.antimicrobial therapy for bacterial,fungal,and mixed infectious keratitis:a prospective randomized phase 3 trial

Background:Infectious keratitis is a major cause of global blindness.We tested whether standalone photoactivated chromophore corneal cross-linking(PACK-CXL)may be an efective frst-line treatment in early to moderate infectious keratitis,compared with standard antimicrobial treatment.Methods:This is a randomized,controlled,multinational phase 3 clinical trial.Participants in fve centers in Egypt,India,Iran,Israel,and China,aged≥18 years,with infectious keratitis of presumed bacterial,fungal,or mixed origin,were randomly assigned(1:1)to PACK-CXL,or antimicrobial therapy.Outcomes measures included healing,defned as time to re-epithelialization of the corneal epithelial defect in the absence of infammatory activity in the anterior chamber and clearance of stromal infltrates.Treatment success was defned as the complete resolution of signs of infection.Results:Between July 21,2016,and March 4,2020,participants were randomly assigned to receive PACK-CXL(n=18)or antimicrobial therapy per American Academy of Ophthalmology(AAO)guidelines(n=21).No participants were lost to follow-up.Four eyes were excluded from the epithelialization time analysis due to treatment failure:two in the antimicrobial therapy group,and two in the PACK-CXL group.Success rates were 88.9%(16/18 patients)in the PACK-CXL group and 90.5%(19/21 patients)in the medication group.There was no signifcant diference in time to complete corneal re-epithelialization(P=0.828)between both treatment groups.Conclusions:PACK-CXL may be an alternative to antimicrobial drugs for frst-line and standalone treatment of early to moderate infectious keratitis of bacterial or fungal origin.

PACK-CXL: Corneal cross-linking in infectious keratitis

Background:Corneal cross-linking(CXL)using ultraviolet light-A(UV-A)and riboflavin is a technique developed in the 1990’s to treat corneal ectatic disorders such as keratoconus.It soon became the new gold standard in multiple countries around the world to halt the progression of this disorder,with good long-term outcomes in keratometry reading and visual acuity.The original Dresden treatment protocol was also later on used to stabilize iatrogenic corneal ectasia appearing after laser-assisted in situ keratomileusis(LASIK)and photorefractive keratectomy(PRK).CXL efficiently strengthened the cornea but was also shown to kill most of the keratocytes within the corneal stroma,later on repopulated by those cells.Review:Ultraviolet-light has long been known for its microbicidal effect,and thus CXL postulated to be able to sterilize the cornea from infectious pathogens.This cytotoxic effect led to the first clinical trials using CXL to treat advanced infectious melting corneal keratitis.Patients treated with this technique showed,in the majority of cases,a stabilization of the melting process and were able to avoid emergentàchaud keratoplasty.Following those primary favorable results,CXL was used to treat beginning bacterial keratitis as a first-line treatment without any adjunctive antibiotics with positive results for most patients.In order to distinguish the use of CXL for infectious keratitis treatment from its use for corneal ectatic disorders,a new term was proposed at the 9th CXL congress in Dublin to rename its use in infections as photoactivated chromophore for infectious keratitis-corneal collagen cross-linking(PACK-CXL).Conclusion:PACK-CXL is now more frequently used to treat infections from various infectious origins.The original Dresden protocol is still used for this purpose.Careful modifications of this protocol could improve the efficiency of this technique in specific clinical situations regarding certain types of pathogens.

Trends in the indications for penetrating keratoplasty in Shandong,2005-2010

AIM: To identify the current indications and the trend shifts for penetrating keraboplasty (PKP) in Shandong. METHODS: The medical charts of all patients who underwent PKP at Shandong Eye Institute from June 1, 2005 to May 31, 2010 were analysed retrospectively. RESULTS: A total of 875 patients (875 eyes) received PKP in this 5-year period, accounting for 61.6% of all corneal transplantation surgeries. The leading indications for PKP were infectious keratitis (37.1%), HSK (19.1%), keratoconus (11.2%), bullous keratopathy (8.5%), regrafting (6.7%) and corneal scarring (4.8%). The percentage of PKP for keratoconus declined year by year, whereas the percentage of bullous keratopathy had a mild annual increase. Fungal infections accounted for 65.2% of the infectious keratitis cases, remaining the leading cause of corneal infection. In addition, 54.1% of bullous keratopathy cases were associated with cataract surgery. The leading initial diagnoses associated with regrafting were infectious keratitis (38.9%), HSK (18.6%) and corneal burn (16.9%). The major causes of regrafting included graft endothelial dysfunction (39.0%), graft ulcer (28.8%) and primary disease recurrence (15.3%). CONCLUSION: Infectious keratitis remained the leading indication for PKP in Shandong, and fungal infections were still the major cause of corneal infections. There was an increasing trend in the percentage of PKP cases indicated for bullous keratopathy but a decline in the same for keratoconus. Even with a decline in the overall proportion among all corneal transplantation surgeries, PKP is still the major corneal transplant choice in Shandong.

Prevalence and associated factors of corneal blindness in Ningxia in northwest China

AIM:To describe the prevalence and demographic characteristics of corneal blindness in an urban and rural region of Ningxia,located in the northwest part of China.METHODS:A stratified,randomized sampling procedure was employed in the study,including urban and rural area of all age group.Visual acuity,anterior segment and ocular fundus were checked.Related factor of corneal disease,including age,gender,education status,ethnic group,location and occupation,were identified according to uniform customized protocol.An eye was defined to be corneal blindness if the visual acuity was【20/400 due to a corneal disease.RESULTS:Three thousand individuals(1290 from urban area and 1710 from rural area)participated in the investigation,with a response rate of 80.380%.The prevalence of corneal blindness was 0.023%in both eyes and 0.733%in at least one eye.The blindness in at least one eye with varied causes was present in 106participants(3.533%)and in bilateral eyes in 34participants(1.133%).The corneal diseases accounted for 20.754%of blindness in at least one eye and 20.588%of bilateral blindness.The prevalence of corneal disease was higher in older and Han ethnic group,especially those who occupied in agriculture and outdoor work.People with corneal blindness were more likely to be older and lower education.Rural population were more likely to suffer from bilateral corneal blindness than the urban population in≥59-year group(χ2=6.716,P=0.019).Infectious,trauma and immune corneal disease were the three leading causes of corneal disease.Trauma cornealdisease was more likely leading to blindness in one eye.However,infectious and immune corneal diseases make more contribution to the bilateral corneal blindness.CONCLUSION:Corneal blindness is a significant burden of in Ningxia population,encompassing a variety of corneal infections and trauma;the majority of those were avoidable.Health promotion strategies and good hygienic conditions have to be developed.

Etiology and failure analysis of anterior lamellar keratoplasty

AIM：To analyze indications and reasons for failure of anterior lamellar keratoplasty（ALK）.METHODS：The clinical records were retrospectively reviewed.Main outcome measures included indications for ALK and reasons for failure of ALK.RESULTS：A total of 434 patients（462 eyes） were treated with ALK at Qingdao Eye Hospital,Shandong Eye Institute from June 1,2009 to May 31,2016.The main indications were infectious keratitis（33.3%）,keratoconus（23.6%）,corneal dystrophy and degeneration（9.8%）,Mooren＇s ulcer（8.4%）,corneal neoplasm（7.8%）,viral keratitis（6.5%） and regrafting（3.7%）.Fungal keratitis accounted for 73.4% in the infectious keratitis cases.ALKs were failed in 36 patients,with the major causes being recurrence of primary diseases（63.9%）.The leading causes of graft failure was Mooren＇s ulcer（36.1%）,followed by infectious keratitis（30.6%）.Recurrence of fungal keratitis accounted for 81.8% in the failed cases after ALK for infectious keratitis cases.CONCLUSION：Infectious keratitis and keratoconus are the main indications for ALK,of which fungal keratitis was the major cause of corneal infections.Recurrence of primary disease is the main reason of graft failure after ALK,in which the main primary diseases associated with graft failure are Mooren＇s ulcer and fungal keratitis.

Changing indications for lamellar keratoplasty in Shandong, 1993-2008

Background With the advancement of microsurgical techniques, lamellar keratoplasty （LK） has been more valued and performed to treat corneal blindness. This study aimed to evaluate the indications and changing trends for LK during the past 16 years in Shandong Eye Institute, an eye center in China. Methods A total of 1529 eyes, predominantly from male （70.7%） patients undergoing LK between January 1993 and December 2008, were enrolled in this study. Data were collected by reviewing patient medical records for demographic characteristics, clinical diagnosis, laboratory findings and risk factors. Surgical times, initial diagnoses and causes of regrafting were recorded. All LKs were sequentially divided into period 1 （from 1993 to 2000） and period 2 （from 2001 to 2008）. Results Rural-dwelling patients in this study numbered 1089 （71.2%）; in all cases of infectious keratitis, rural patients accounted for 90.5%. The leading indications for LK were infectious keratitis （31.0%）, corneal trauma （21.1%）, keratoconus （18.7%）, corneal dystrophy and degeneration （7.3%）, regrafting （7.1%）, immunologic disorders （6.7%）, congenital abnormalities and corneal tumor （4.1%） and corneal scarring （3.1%）. The most common subcategory of infectious keratitis was fungal keratitis （67.5%）. Fusarium solani was the most morbigenous fungi. Among the patients, 73.1% of thermal burns were caused by hot molten metal, and 47.8% of alkali burns by lime. Dermoid was the most common indication for congenital abnormalities. The two main initial diagnoses from 109 regrafting cases were corneal trauma （45.9%） and Mooren＇s ulcer （27.5%）. The most common cause for regrafting was immune rejection （35.8%）. Infectious keratitis was the most common indication for LK from 16.0% in period 1 to 41.1% in period 2, followed by keratoconus （16.8%） and corneal trauma （14.5%）. Conclusions During the past 16 years, there have been major changes in the constituent ratios of leading indications for LK in Shangdong. Infectious keratitis has become the most common indication for LK. Fungal keratitis was the most common subcategory of infectious keratitis.