Pneumonia is a common complication in organ transplantation patients. Multiple respiratory pathogens such as bacteria, viruses and fungi are potentially coexisted. A 60-year-old male with left eye post corneal transpl...Pneumonia is a common complication in organ transplantation patients. Multiple respiratory pathogens such as bacteria, viruses and fungi are potentially coexisted. A 60-year-old male with left eye post corneal transplantation developed acute severe pneumonia caused by <em>Pneumocystis jiroveci</em> (PJP) coinfection with <em>Nocardia spp</em>. and <em>Cytomegalovirus</em> (CMV). He was hospitalized due to acute respiratory failure. Chest radiographs and chest Computed Tomography (CT) revealed extensive ground-glass opacities. PJP was diagnosed from Bronchoalveolar Lavage Fluid (BALF). The pneumonia was persistent despite of receiving intravenous cotrimoxazole. Tracheal aspirate showed faint gram-positive filamentous beaded branching organisms. Consequently <em>Nocardia spp</em>. was proven. Intravenous cotrimoxazole was continued and intravenous imipenem was added. After a course of dual antibiotics, pneumonia was gradually improved. A week after, he developed the worsened acute respiratory failure. The bronchoscopy was performed. The new pathogens were not detected from BALF microbiology. The BALF cytology was unremarkable. PJP was detected by Polymerase Chain Reaction (PCR) from BALF. CMV antigenemia was detected from BALF and blood. Intravenous ganciclovir was given. This report describes PJP coinfected with <em>Nocardia spp</em>. and CMV in post corneal transplantation patient suffering from severe pneumonia. Multiple respiratory pathogens are common among transplantation patients representing host immunosuppression and inadequate antimicorbial prophylaxis.展开更多
This short report includes 5 eyes of 5 patients(mean age 63.2±12 years)who underwent a tectonic keratoplasty[deep anterior lamellar keratoplasty(DALK)or penetrating keratoplasty(PK)]in order to rehabilitate the e...This short report includes 5 eyes of 5 patients(mean age 63.2±12 years)who underwent a tectonic keratoplasty[deep anterior lamellar keratoplasty(DALK)or penetrating keratoplasty(PK)]in order to rehabilitate the eye after the extrusion of the non-perforating keratoprosthesis(Kpro)KeraKlear(KeraMed,USA).The non-perforating Kpro was extruded after a mean period of 21.4±21.8 months due to melting.In two cases,the keratoplasty was performed the same day of the non-perforating Kpro removal due to a severe melting,while in the other three cases it was performed one to 3 months later.Two eyes received a DALK,but in 3 eyes a macroscopic Descemet membrane perforation forced the conversion into a PK.The mean follow-up period after the keratoplasty was 16.8±6.6 months.No cases of rejection were recorded.All the 5 eyes achieved“anatomical success”(transparent graft,with no signs of infection or inflammation).Two eyes showed limited“functional success”because the achievement of the best visual potential was prevented by the development of glaucomatous optic atrophy during the follow-up period.In conclusion,this short report presents an unexpected success of a keratoplasty performed with a tectonic purpose after the extrusion of the non-perforating Kpro because the corneal graft remained transparent,without neovascularization or scarring during the follow-up period.This initial evidence shows some encouraging results regarding graft survival rate and the achievement of a useful visual rehabilitation with keratoplasty after a nonperforating Kpro failure instead of repeating the Kpro implantation.展开更多
AIM: To examine the therapeutic effects of tocilizumab on experimental corneal transplantation and its effect on Treg/Th17 balance. METHODS: Allograft corneal graft was performed between host Sprague Dawley and Wistar...AIM: To examine the therapeutic effects of tocilizumab on experimental corneal transplantation and its effect on Treg/Th17 balance. METHODS: Allograft corneal graft was performed between host Sprague Dawley and Wistar donor rats.The rats were randomly divided into four groups: normal,autograft, allograft, and allograft treated with tocilizumab.Kaplan-Meier was performed to draw the survival curve.The protein levels of interleukin-17A(IL-17A), vascular endothelial growth factor(VEGF), and forkhead box protein3(Foxp3) were measured by immunohistochemistry.The mRNA levels of IL-17A, VEGF, retinoid-related orphan receptor gammat(RORγt), interleukin-6(IL-6) and Foxp3 were detected by reverse transcription real-time polymerase chain reaction(RT-PCR). The Treg and Th17 cells were investigated by flow cytometry. RESULTS: The survival time of tocilizumab group was(24±1.27 d) longer than that of allograft group(10±0.55 d).Moreover, immunohistochemical examination revealed that IL-17A and VEGF protein levels in the allograft group were significantly higher than that of tocilizumab group(P<0.01),while Foxp3 levels in the allograft group was significantly lower than that of the tocilizumab treated group(P<0.001).Flow cytometry showed that the number of Th17 cellsin allograft group was significantly higher than that in tocilizumab group(P<0.001). Meanwhile, the number of Tregs was significantly lower than in tocilizumab group(P<0.001). Simultaneously, Foxp3 m RNA expression level in corneal tissues of tocilizumab treated group was significantly higher than other groups(P<0.001). CONCLUSION: These findings suggest that tocilizumab may promote corneal allograft survival, possibly by modulating Treg-Th17 balance.展开更多
Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on d...Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.展开更多
Background:Disruption of the microstructure in corneal stroma can lead to the loss of transparency.The lack of a characterization method for the microstructure prevents such scaffolds to be implemented in tissue trans...Background:Disruption of the microstructure in corneal stroma can lead to the loss of transparency.The lack of a characterization method for the microstructure prevents such scaffolds to be implemented in tissue transplantation.The non-invasive,three-dimensional(3D)rendering multiphoton microscopy(MPM)poses the potential to solve this problem.Methods:MPM images and data analyses were performed with three kinds of samples with known and different quality.Isosurfaces(ISOs)were constructed for the evaluation of void volume and collagen distribution.Results:The differences in the microstructures of these samples were revealed with clear indications and links to their behaviours in rehydration and possible transparency.According to this analysis,the scaffold with the highest void space ratio amongst the three presented the highest successful rates to be thoroughly rehydrated.Conclusions:Such a method can be developed for assessing the quality of tissue engineered corneas,or donated corneas,and be useful as a powerful research tool in cornea related research.展开更多
Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases requir...Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases require surgical intervention.This review provides an update on the current treatment modalities of corneal surgery available for the management of advanced corneal ectasias.展开更多
Cellular therapy of the corneal stroma,with either ocular or extraocular stem cells,has been gaining a lot of interest over the last decade.Multiple publications from different research groups are showing its potentia...Cellular therapy of the corneal stroma,with either ocular or extraocular stem cells,has been gaining a lot of interest over the last decade.Multiple publications from different research groups are showing its potential benefits in relation to its capacity to improve or alleviate corneal scars,improve corneal transparency in metabolic diseases by enhancing the catabolism of the accumulated molecules,generate new organized collagen within the host stroma,and its immunosuppressive and immunomodulatory properties.Autologous extraocular stem cells do not require a healthy contralateral eye and they do not involve any ophthalmic procedures for their isolation.Mesenchymal stem cells have been the most widely assayed and have the best potential to differentiate into functional adult keratocytes in vivo and in vitro.While embryonic stem cells have been partially abandoned due to ethical implications,the discovery of the induced pluripotent stem cells(iPSC)has opened a new and very promising field for future research as they are pluripotent cells with the capacity to theoretically differentiate into any cell type,with the special advantage that they are obtained from adult differentiated cells.Cellular delivery into the corneal stroma has been experimentally assayed in vivo in multiple ways:systemic versus local injections with or without a carrier.Encouraging preliminary human clinical data is already available although still very limited,and further research is necessary in order to consolidate the clinical applications of this novel therapeutic line.展开更多
Background:To assess the knowledge of Singaporean youth regarding corneal donation and gauge their willingness to donate their corneas.Methods:We conducted a cross-sectional study among 500 students from five tertiary...Background:To assess the knowledge of Singaporean youth regarding corneal donation and gauge their willingness to donate their corneas.Methods:We conducted a cross-sectional study among 500 students from five tertiary institutions in Singapore.All students answered self-administered questionnaires which included seven questions that tested knowledge and three questions that determined willingness to donate corneas.Results:Among 500 Singaporean youth aged 18 to 25,most students(73.2%)answered 3 or fewer of the 7 questions about corneal donation correctly.With regards to the willingness to donate,155(31%)were willing to donate their corneas,111(22.2%)were not willing to donate their corneas,and 234(46.8%)were undecided.Willingness to donate corneas was associated with an older age group(21 to 25 years old),those who are non-Muslims,and have good basic knowledge.Particularly,students with good basic knowledge were 1.71 times more likely to willingly donate their corneas.Conclusion:The knowledge of the Singaporean youth regarding corneal donation and transplantation is poor.Since insufficient information was cited as the most common reason for being undecided in regards to corneal donation,specific and tailored programs to increase knowledge and awareness are needed to convince the youth to support corneal donation.展开更多
Background:Cytomegalovirus(CMV)can manifest as corneal endotheliitis in immunocompetent individuals.Early diagnosis is prudent to prevent endothelial cell loss,which could ultimately lead to corneal decompensation.CMV...Background:Cytomegalovirus(CMV)can manifest as corneal endotheliitis in immunocompetent individuals.Early diagnosis is prudent to prevent endothelial cell loss,which could ultimately lead to corneal decompensation.CMV DNA was first detected in an eye with corneal endotheliitis in 2006;since then,clinical evidence from numerous case reports and case series have accumulated.Main text:In this narrative review,we identified several drugs,including ganciclovir,valganciclovir,and their combination in oral,intravenous,intravitreal,and topical forms in different concentrations,together with the judicious use of topical steroids,have reported variable success.There has yet to be any prospective comparative study evaluating the efficacy and safety of these assorted forms of treatment;clinical evidence is based on case reports and case series.CMV endotheliitis presenting with corneal edema can masquerade as other corneal diseases and thus poses a great challenge especially in post-keratoplasty eyes.Heightened awareness is needed before and after keratoplasty to start prompt prophylaxis and treatment.Conclusion:There is no consensus on the management of CMV endotheliitis.Further studies are much needed to elucidate the optimal treatment modality,regime,and duration in the treatment and prophylaxis of CMV endotheliitis.展开更多
Background:In the general population,1 in 2000 people has keratoconus.Indians and other people from Southeast Asia have a higher incidence of keratoconus.Children with keratoconus typically present earlier in life and...Background:In the general population,1 in 2000 people has keratoconus.Indians and other people from Southeast Asia have a higher incidence of keratoconus.Children with keratoconus typically present earlier in life and with a more severe disease.Rubbing the eyes has been identified as a risk factor.Children have a higher incidence and a faster rate of keratoconus progression.Visual rehabilitation in children with keratoconus is challenging.They have a low compliance with contact lens use.Many of these children require penetrating keratoplasty at an early age.Therefore,stopping the progression of keratoconus in children is of paramount importance.Main text:Compared to treatment,keratoconus progression prophylaxis is not only preferable,but also easier.Corneal collagen cross-linking has been shown to be safe and effective in stopping its progression in children.The Dresden protocol,which involves central corneal deepithelization(7-9 mm),saturation of the stroma with riboflavin(0.25%),and 30 min UV-A exposure,has proven to be the most successful.Two significant disadvantages of the typical Dresden regimen are the prolonged operating time and the significant post-operative pain.Accelerated-CXL(9 mW/cm^(2) x 10 min)has been studied to reduce operative time and has been shown to be equally effective in some studies.Compared to accelerated CXL or traditional CXL,epi-off procedures,transepithelial treatment without the need for de-epithelialization and without postoperative discomfort,have been shown to be safer but less effective.Corneal crosslinking should only be performed after treating children with active vernal keratoconjunctivitis.Corneal opacity,chronic corneal edema,sterile infiltrates,and microbial keratitis have been reported after cross-linking of corneal collagen.Conclusions:The"Dresden protocol",also known as the conventional corneal cross-linking approach,should be used to halt the progression of keratoconus in young patients.However,if the procedure needs to be completed more rapidly,accelerated corneal crosslinking may be considered.Transepithelial corneal cross-linking has been proven to be less effective at stabilizing keratoconus,although being more safer.展开更多
文摘Pneumonia is a common complication in organ transplantation patients. Multiple respiratory pathogens such as bacteria, viruses and fungi are potentially coexisted. A 60-year-old male with left eye post corneal transplantation developed acute severe pneumonia caused by <em>Pneumocystis jiroveci</em> (PJP) coinfection with <em>Nocardia spp</em>. and <em>Cytomegalovirus</em> (CMV). He was hospitalized due to acute respiratory failure. Chest radiographs and chest Computed Tomography (CT) revealed extensive ground-glass opacities. PJP was diagnosed from Bronchoalveolar Lavage Fluid (BALF). The pneumonia was persistent despite of receiving intravenous cotrimoxazole. Tracheal aspirate showed faint gram-positive filamentous beaded branching organisms. Consequently <em>Nocardia spp</em>. was proven. Intravenous cotrimoxazole was continued and intravenous imipenem was added. After a course of dual antibiotics, pneumonia was gradually improved. A week after, he developed the worsened acute respiratory failure. The bronchoscopy was performed. The new pathogens were not detected from BALF microbiology. The BALF cytology was unremarkable. PJP was detected by Polymerase Chain Reaction (PCR) from BALF. CMV antigenemia was detected from BALF and blood. Intravenous ganciclovir was given. This report describes PJP coinfected with <em>Nocardia spp</em>. and CMV in post corneal transplantation patient suffering from severe pneumonia. Multiple respiratory pathogens are common among transplantation patients representing host immunosuppression and inadequate antimicorbial prophylaxis.
基金This publication has been carried out in the framework of the Red Temática de Investigación Cooperativa en Salud(RETICS),reference number RD16/0008/0012financed by the Instituto Carlos III–General Subdirection of Networks and Cooperative Investigation Centers(R&D&I National Plan 2008–2011)the European Regional Development Fund(Fondo Europeo de Desarrollo Regional FEDER).
文摘This short report includes 5 eyes of 5 patients(mean age 63.2±12 years)who underwent a tectonic keratoplasty[deep anterior lamellar keratoplasty(DALK)or penetrating keratoplasty(PK)]in order to rehabilitate the eye after the extrusion of the non-perforating keratoprosthesis(Kpro)KeraKlear(KeraMed,USA).The non-perforating Kpro was extruded after a mean period of 21.4±21.8 months due to melting.In two cases,the keratoplasty was performed the same day of the non-perforating Kpro removal due to a severe melting,while in the other three cases it was performed one to 3 months later.Two eyes received a DALK,but in 3 eyes a macroscopic Descemet membrane perforation forced the conversion into a PK.The mean follow-up period after the keratoplasty was 16.8±6.6 months.No cases of rejection were recorded.All the 5 eyes achieved“anatomical success”(transparent graft,with no signs of infection or inflammation).Two eyes showed limited“functional success”because the achievement of the best visual potential was prevented by the development of glaucomatous optic atrophy during the follow-up period.In conclusion,this short report presents an unexpected success of a keratoplasty performed with a tectonic purpose after the extrusion of the non-perforating Kpro because the corneal graft remained transparent,without neovascularization or scarring during the follow-up period.This initial evidence shows some encouraging results regarding graft survival rate and the achievement of a useful visual rehabilitation with keratoplasty after a nonperforating Kpro failure instead of repeating the Kpro implantation.
基金Supported by Science and Technology Planning Project of Guangdong Province (No.2017A020211005)Science and Technology Programme of Guangzhou, China 2016 (No.201607010386)
文摘AIM: To examine the therapeutic effects of tocilizumab on experimental corneal transplantation and its effect on Treg/Th17 balance. METHODS: Allograft corneal graft was performed between host Sprague Dawley and Wistar donor rats.The rats were randomly divided into four groups: normal,autograft, allograft, and allograft treated with tocilizumab.Kaplan-Meier was performed to draw the survival curve.The protein levels of interleukin-17A(IL-17A), vascular endothelial growth factor(VEGF), and forkhead box protein3(Foxp3) were measured by immunohistochemistry.The mRNA levels of IL-17A, VEGF, retinoid-related orphan receptor gammat(RORγt), interleukin-6(IL-6) and Foxp3 were detected by reverse transcription real-time polymerase chain reaction(RT-PCR). The Treg and Th17 cells were investigated by flow cytometry. RESULTS: The survival time of tocilizumab group was(24±1.27 d) longer than that of allograft group(10±0.55 d).Moreover, immunohistochemical examination revealed that IL-17A and VEGF protein levels in the allograft group were significantly higher than that of tocilizumab group(P<0.01),while Foxp3 levels in the allograft group was significantly lower than that of the tocilizumab treated group(P<0.001).Flow cytometry showed that the number of Th17 cellsin allograft group was significantly higher than that in tocilizumab group(P<0.001). Meanwhile, the number of Tregs was significantly lower than in tocilizumab group(P<0.001). Simultaneously, Foxp3 m RNA expression level in corneal tissues of tocilizumab treated group was significantly higher than other groups(P<0.001). CONCLUSION: These findings suggest that tocilizumab may promote corneal allograft survival, possibly by modulating Treg-Th17 balance.
基金Supported by The Ophthalmic Research Center,Shahid Beheshti University of Medical Sciences,Tehran,Iran
文摘Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.
文摘Background:Disruption of the microstructure in corneal stroma can lead to the loss of transparency.The lack of a characterization method for the microstructure prevents such scaffolds to be implemented in tissue transplantation.The non-invasive,three-dimensional(3D)rendering multiphoton microscopy(MPM)poses the potential to solve this problem.Methods:MPM images and data analyses were performed with three kinds of samples with known and different quality.Isosurfaces(ISOs)were constructed for the evaluation of void volume and collagen distribution.Results:The differences in the microstructures of these samples were revealed with clear indications and links to their behaviours in rehydration and possible transparency.According to this analysis,the scaffold with the highest void space ratio amongst the three presented the highest successful rates to be thoroughly rehydrated.Conclusions:Such a method can be developed for assessing the quality of tissue engineered corneas,or donated corneas,and be useful as a powerful research tool in cornea related research.
文摘Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases require surgical intervention.This review provides an update on the current treatment modalities of corneal surgery available for the management of advanced corneal ectasias.
文摘Cellular therapy of the corneal stroma,with either ocular or extraocular stem cells,has been gaining a lot of interest over the last decade.Multiple publications from different research groups are showing its potential benefits in relation to its capacity to improve or alleviate corneal scars,improve corneal transparency in metabolic diseases by enhancing the catabolism of the accumulated molecules,generate new organized collagen within the host stroma,and its immunosuppressive and immunomodulatory properties.Autologous extraocular stem cells do not require a healthy contralateral eye and they do not involve any ophthalmic procedures for their isolation.Mesenchymal stem cells have been the most widely assayed and have the best potential to differentiate into functional adult keratocytes in vivo and in vitro.While embryonic stem cells have been partially abandoned due to ethical implications,the discovery of the induced pluripotent stem cells(iPSC)has opened a new and very promising field for future research as they are pluripotent cells with the capacity to theoretically differentiate into any cell type,with the special advantage that they are obtained from adult differentiated cells.Cellular delivery into the corneal stroma has been experimentally assayed in vivo in multiple ways:systemic versus local injections with or without a carrier.Encouraging preliminary human clinical data is already available although still very limited,and further research is necessary in order to consolidate the clinical applications of this novel therapeutic line.
文摘Background:To assess the knowledge of Singaporean youth regarding corneal donation and gauge their willingness to donate their corneas.Methods:We conducted a cross-sectional study among 500 students from five tertiary institutions in Singapore.All students answered self-administered questionnaires which included seven questions that tested knowledge and three questions that determined willingness to donate corneas.Results:Among 500 Singaporean youth aged 18 to 25,most students(73.2%)answered 3 or fewer of the 7 questions about corneal donation correctly.With regards to the willingness to donate,155(31%)were willing to donate their corneas,111(22.2%)were not willing to donate their corneas,and 234(46.8%)were undecided.Willingness to donate corneas was associated with an older age group(21 to 25 years old),those who are non-Muslims,and have good basic knowledge.Particularly,students with good basic knowledge were 1.71 times more likely to willingly donate their corneas.Conclusion:The knowledge of the Singaporean youth regarding corneal donation and transplantation is poor.Since insufficient information was cited as the most common reason for being undecided in regards to corneal donation,specific and tailored programs to increase knowledge and awareness are needed to convince the youth to support corneal donation.
文摘Background:Cytomegalovirus(CMV)can manifest as corneal endotheliitis in immunocompetent individuals.Early diagnosis is prudent to prevent endothelial cell loss,which could ultimately lead to corneal decompensation.CMV DNA was first detected in an eye with corneal endotheliitis in 2006;since then,clinical evidence from numerous case reports and case series have accumulated.Main text:In this narrative review,we identified several drugs,including ganciclovir,valganciclovir,and their combination in oral,intravenous,intravitreal,and topical forms in different concentrations,together with the judicious use of topical steroids,have reported variable success.There has yet to be any prospective comparative study evaluating the efficacy and safety of these assorted forms of treatment;clinical evidence is based on case reports and case series.CMV endotheliitis presenting with corneal edema can masquerade as other corneal diseases and thus poses a great challenge especially in post-keratoplasty eyes.Heightened awareness is needed before and after keratoplasty to start prompt prophylaxis and treatment.Conclusion:There is no consensus on the management of CMV endotheliitis.Further studies are much needed to elucidate the optimal treatment modality,regime,and duration in the treatment and prophylaxis of CMV endotheliitis.
文摘Background:In the general population,1 in 2000 people has keratoconus.Indians and other people from Southeast Asia have a higher incidence of keratoconus.Children with keratoconus typically present earlier in life and with a more severe disease.Rubbing the eyes has been identified as a risk factor.Children have a higher incidence and a faster rate of keratoconus progression.Visual rehabilitation in children with keratoconus is challenging.They have a low compliance with contact lens use.Many of these children require penetrating keratoplasty at an early age.Therefore,stopping the progression of keratoconus in children is of paramount importance.Main text:Compared to treatment,keratoconus progression prophylaxis is not only preferable,but also easier.Corneal collagen cross-linking has been shown to be safe and effective in stopping its progression in children.The Dresden protocol,which involves central corneal deepithelization(7-9 mm),saturation of the stroma with riboflavin(0.25%),and 30 min UV-A exposure,has proven to be the most successful.Two significant disadvantages of the typical Dresden regimen are the prolonged operating time and the significant post-operative pain.Accelerated-CXL(9 mW/cm^(2) x 10 min)has been studied to reduce operative time and has been shown to be equally effective in some studies.Compared to accelerated CXL or traditional CXL,epi-off procedures,transepithelial treatment without the need for de-epithelialization and without postoperative discomfort,have been shown to be safer but less effective.Corneal crosslinking should only be performed after treating children with active vernal keratoconjunctivitis.Corneal opacity,chronic corneal edema,sterile infiltrates,and microbial keratitis have been reported after cross-linking of corneal collagen.Conclusions:The"Dresden protocol",also known as the conventional corneal cross-linking approach,should be used to halt the progression of keratoconus in young patients.However,if the procedure needs to be completed more rapidly,accelerated corneal crosslinking may be considered.Transepithelial corneal cross-linking has been proven to be less effective at stabilizing keratoconus,although being more safer.
