Virtual keratoconus monitoring clinic in a tertiary university hospital in the United Kingdom

Purpose: To describe a new pathway for virtual keratoconus (KC) monitoring in the corneal department of a tertiary referral center in the UK during the coronavirus disease 2019 (COVID?19) pandemic. Methods: A virtual outpatient clinic to monitor KC patients (KC PHOTO clinic) was created. All patients from the KC database in our department were included. At each hospital visit, patients’ visual acuity and tomography (Pentacam; Oculus, Wetzlar, Germany) were collected by a health?care assistant and an ophthalmic technician, respectively. The results were virtually reviewed by a corneal optometrist to identify stability or progression of KC and discussed with a consultant if needed. Those with progression were contacted by telephone and listed for corneal crosslinking (CXL). Results: From July 2020 until May 2021, 802 patients were invited to attend the virtual KC outpatient clinic. Of them, 536 patients (66.8%) attended and 266 (33.2%) did not attend. After corneal tomography analysis, 351 (65.5%) were stable, 121 (22.6%) showed no definite evidence of progression, and 64 (11.9%) showed progression. Forty?one (64%) patients with progressive KC were listed for CXL and the remaining 23 patients deferred treatment after the pandemic. By converting a face?to?face clinic to a virtual clinic, we were able to increase our capacity by nearly 500 appointments per year. Conclusion: In pandemic times, hospitals have developed novel methods of delivering safe patient care. KC PHOTO is a safe, effective, and innovative method of monitoring KC patients and diagnosing progression. In addition, virtual clinics can increase the clinic capacity tremendously and reduce the need of face?to?face appointments, which is beneficial in pandemic conditions.

Clinical efficacy evaluation of accelerated epithelium-off corneal collagen cross-linking on corneal ectasia after keratorefractive surgery / 中华实验眼科杂志

Objective:To investigate the efficacy and safety of accelerated epithelium-off corneal collagen cross-linking (CXL) in the treatment of corneal ectasia after keratorefractive surgery.Methods:An observational case series study was performed.Twelve patients (22 eyes) diagnosed with corneal ectasia after keratorefractive surgery in the First Affiliated Hospital of Army Medical University were enrolled from January 2016 to December 2018.All the patients received accelerated epithelium-off CXL and were followed up for 12 months.Before and 1 week, 1, 3, 6, and 12 months after the operation, the uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) converted to the logarithm of the minimum angle of resolution (LogMAR) unit were measured.The sphericity, cylindricity, and spherical equivalent were examined by Topcon auto refractor.The maximum keratometry (Kmax) of the front surface, mean keratometry (Km) of the front surface, Km of the back surface, symmetry index of front surface (SIf), symmetry index of back surface (SIb), thinnest corneal thickness (TCT), total aberrations, total high-order aberrations, coma aberration, trefoil aberration and spherical aberration were detected by the Sirius analyzer.The depth of corneal demarcation lines was determined by optical coherence tomography.The intraocular pressure was measured by the non-contact tonometry.The corneal endothelial cell density was assayed by the endothelial cell densitometry.The inflammatory reaction and haze were observed with a slit lamp at different time points after surgery.This study adhered to the Declaration of Helsinki.The study protocol was approved by the First Affiliated Hospital of Army Medical University (No.KY2020063). Written informed consent was obtained from each patient before entering the cohort.Results:Among the 22 eyes of 12 cases, 3 eyes of 2 cases (13.64%) underwent small incision lenticule extraction, and 19 eyes of 10 cases (86.36%) underwent excimer laser in situ keratomileusis.The UCVA (LogMAR), BCVA (LogMAR), cylindricity and spherical equivalent before the operation were 0.61±0.42, 0.24±0.23, (-2.83±2.39)D, (-3.60±2.66)D, which were significantly worse than 0.45±0.31, 0.12±0.15, (-2.11±1.67)D, (-3.12±2.31)D at 12 months after the operation ( t=4.054, 4.956, -3.728, -2.742; all at P<0.05). The front surface Kmax, front surface Km and SIf at 12 months after the operation were (48.37±5.80), (41.49±3.04), (5.36±4.07)D, which were significantly lower than (49.61±5.97), (41.66±2.97), (5.85±4.18)D before the operation ( t=5.949, 2.278, 2.719; all at P<0.05). There was no significant difference in sphericity, Km of the back surface, SIb, TCT, total aberrations, total high-order aberrations, coma aberration, trefoil aberration, spherical aberration, intraocular pressure and endothelial cell density between before and 12 months after the operation (all at P>0.05). Grade 0.5-2 haze occurred in 8 eyes of 4 patients one month postoperatively.After administration of prednisolone acetate eye drops, haze decreased or disappeared 3 months postoperatively, with UCVA and BCVA unchanged.A corneal demarcation line with a depth of (285.40±51.61)μm was found in 11 eyes of 6 cases at 1 month after operation. Conclusions:Accelerated epithelium-off CXL can significantly improve visual acuity, reduce corneal astigmatism and corneal curvature, as well as effectively prevent the progress of corneal ectasia.

Comparative study of corneal thickness and thinnest point position of keratoconus measured by Pentacam HR and RTVue OCT / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the difference, correlation, and consistency of corneal thickness and the thinnest point position detected by Pentacam HR corneal topography map and RTVue optical coherence tomography(OCT)in patients with keratoconus.METHODS: Cross-sectional comparative study. The corneal curvature map, corneal thickness map, thinnest point position, and thinnest point thickness were detected by Pentacam HR and RTVue OCT. Paired sample t-test was used for data consistent with normal distribution, and paired sample rank sum test was used for data inconsistent with normal distribution. Spearman correlation analysis and Bland-Altman analysis were used for the correlation and consistency of the two measurement methods.RESULTS: A total of 63 patients(105 eyes)with keratoconus were included in this study, including 49 males(77.8%)and 14 females(22.2%), aged 22.24±6.19 years; among them, relevant data of Pentacam HR topographic map: Km was 47.85±4.73D and Kmax was 55.43±8.72D. In measuring central corneal thickness and the thinnest point thickness of keratoconus, the Pentacam HR was 4.70μm and 19.46μm thicker than the mean value measured by RTVue OCT(P&#x003C;0.05). There was no significant difference between the horizontal and vertical coordinates of the thinnest points measured by the two devices(P&#x003E;0.05). The central corneal thickness and the thinnest point thickness measured by the two devices were highly correlated, the horizontal coordinate of the thinnest point was moderately correlated, and the vertical coordinate of the thinnest point was weakly correlated. Bland-Altman analysis showed that the central corneal thickness, the thinnest point thickness, the horizontal coordinate of the thinnest point, and the vertical coordinate of the thinnest point were 95.2%(100/105)and 93.3%(98/105), 95.2%(100/105), 95.2%(100/105)respectively, which were within the 95% consistency limit, while the consistency ranges were -36.00～+26.62μm, -42.27～+3.36μm, -0.80～+0.84mm, and -1.95～+1.06mm, respectively.CONCLUSION: In keratoconus, the central corneal thickness and the thinnest point thickness measured by Pentacam HR were higher than those measured by RTVue OCT. It is not recommended that the central corneal thickness and the thinnest point thickness measured by the two instruments be interchangeable in clinical use because of the wide range of consistency between the two instruments' results. The position of the thinnest corneal point measured by the two instruments is similar and consistent, so it could be considered to replace the measured values of the two instruments in clinical use.

Repetibilidade do estudo tomográfico da córnea com Scheimpflug rotacional, em olhos normais, olhos com ceratocone e olhos com ceratocone operados por crosslinking / Repeatability of the tomographic study of the cornea with a rotational Scheimpflug in normal eyes, eyes with keratoconus and eyes with crosslinking for keratoconus

RESUMO Objetivo Avaliar a precisão da tomografia corneana com imagens de Scheimpflug (Pentacam® AXL, OCULUS, Wetzlar, Alemanha) nos padrões de escaneamento com 25 e 50 imagens, verificando sua repetibilidade e reprodutibilidade em olhos normais, com ceratocone e com ceratocone após crosslinking. Métodos Estudo prospectivo, transversal, misto, no qual foram incluídos os pacientes que tinham córneas normais, ou com ceratocone; e não tinham realizado cirurgias corneanas, com exceção do crosslinking. Foram excluídos os pacientes que tivessem realizado outras cirurgias, como implante de anel intracorneano ou transplante de córnea. Foram realizadas três medidas com 25 imagens e três medidas com 50 imagens em cada olho incluído no estudo. Resultados O estudo avaliou 54 olhos de 41 pacientes. Destes, dez (18,52%) olhos eram com córneas normais e sem cirurgia ocular prévia aleatoriamente selecionados de 5 pacientes; 22 (40,74%) olhos aleatoriamente selecionados de 18 pacientes com ceratocone, sem cirurgia ocular prévia; e 22 (40,74%) olhos com ceratocone de 18 pacientes operados por crosslinking. No estudo da repetibilidade, percebemos uma maior variação de valores em todos os índices nos pacientes com ceratocone comparados aos de pacientes com olhos normais, em grande parte dos parâmetros analisados. Conclusão Não houve diferença significativa entre os métodos de escaneamento por 25 e 50 imagens, sendo o escaneamento por 25 imagens mais conveniente. A presença de ceratocone teve impacto negativo na repetibilidade de ambos os tipos de exame, e foi grande a concordância entre os métodos nos três grupos estudados. O coeficiente de repetibilidade permite considerar a relevância clínica dos dados para avaliar a progressão de ceratocone.

ABSTRACT Objective To evaluate the accuracy of corneal tomography with Scheimpflug images (Pentacam® AXL, OCULUS, Wetzlar, Germany) in scanning patterns with 25 and 50 images, by analyzing their repeatability and reproducibility in normal eyes, eyes with keratoconus and with keratoconus after crosslinking. Methods Prospective, cross-sectional, mixed study including patients who had normal corneas, or who had keratoconus, who had not undergone corneal surgery, with the exception of crosslinking. Patients who had undergone surgery for intracorneal ring implantation or corneal transplantation were excluded. Three measurements were performed with 25 images and three measurements were performed with 50 images on each eye included in the study. Results The study evaluated a total of 54 eyes of 41 patients. Of these, 10 (18.52%) eyes had normal corneas, without previous eye surgery, 22 (40.74%) were eyes with keratoconus, without previous eye surgery, and 22 (40.74%) were eyes with keratoconus, with crosslinking for keratoconus. In the study of repeatability, we noticed a greater variation of values in all indices in patients with KC compared to those with normal eyes, in most of the parameters analyzed. Conclusion There is no significant difference between the scanning methods with 25 and 50 images. However, 25 scans has advantages that make it the main method suggested. The presence of keratoconus has a negative impact on the repeatability of both types of examination, and there is great agreement between the methods in the three groups studied. The high repeatability coefficient in some parameters suggests that these data should be used with care in the assessment of keratoconus progression.

Efficacy of epithelial-off accelerated corneal cross-linking in the treatment of advanced keratoconus / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the efficacy of epithelial-off accelerated corneal cross-linking(CXL)in the treatment of advanced keratoconus.METHODS: A retrospective study was performed on data collected from 32 patients(43 eyes)with advanced keratoconus who underwent epithelial-off accelerated CXL at Ningxia Eye Hospital from April 2020 to December 2021. Slit-lamp, intraocular pressure, uncorrected visual acuity(UCVA), corrected visual acuity, specular microscope, Pentacam and Corvis ST were tested before and at 1, 3 and 6mo after surgery. Preoperative and postoperative corneal condition, UCVA, best corrected visual acuity(BCVA)and the values of corneal endothelial, maximum keratometry(Kmax), thinnest corneal thickness(TCT), anterior and posterior surfaces of the cornea K1, K2, biomechanically corrected intraocular pressure(bIOP), applanation time 1(A1T), applanation length 1(A1L), applanation velocity 1(A1V), applanation time 2(A2T), applanation length 2(A2L), applanation velocity 2(A2V), highest concavity deformation amplitude(HCDA), radius at highest curvature(HCR), highest concavity peak distance(HCPD)and stiffness parameter at first applanation(SP-A1)were recorded.RESULTS: There were differences between UCVA(LogMAR; 1.06±0.49, 0.78±0.39)and BCVA(LogMAR; 0.48±0.34, 0.38±0.29)before and at 6mo after surgery(P&#x003C;0.05), but there were no differences in corneal endothelial cells(2917.39±288.38 vs. 2959.19±336.27 cells/mm2, P=0.477). There were differences among Kmax, TCT, anterior surface K1 and K2 and posterior surface K1 before and after surgery(P&#x003C;0.05), and all increased at 1mo after surgery then returned to preoperative level at 3mo after surgery, while there was no difference in the posterior K2. Furthermore, there were statistical significance in A1T, HCPD and SP-A1 before and after surgery(P&#x003C;0.05), while there were no statistical significance in A1L, A1V,A2T, A2L, A2V, HCDA, HCR and bIOP(P&#x003E;0.05).CONCLUSION: Epithelial-off accelerated CXL can prevent the progression of keratoconus within half year after surgery, and it has certain safety.

Assessment of the postoperative effect of corneal cross-linking on keratoconus using the ABCD grading system

Purpose: To monitor the changes in the ABCD grading system during a one?year follow?up after a corneal cross?linking (CXL) procedure. Methods: This prospective study included 30 eyes of 25 patients with keratoconus, who received the CXL treatment. The patients with a history of ocular trauma or surgery and other corneal pathology were excluded from the study. The patients were examined at the baseline visit and followed up at 3, 6, and 12 months after the CXL. All the patients underwent a standard CXL procedure with visual acuity and Scheimpflug tomography testing at each visit. The corneal parameters and ABCD grading were monitored throughout the follow?up period. Results: There were no significant changes of parameter A and anterior radius curvature (ARC) in the ABCD grading system. Parameters B and D showed progression postoperatively, with an improvement of parameter D on the final visit. Parameter C showed a statistically significant increase at all three post?CXL visits, but a constant gradual decrease in the value over time. Conclusion: The ABCD grading system can be very useful in monitoring the progression of keratoconus (KC), but it can also help in monitoring the efficacy of corneal cross?linking. The anterior surface parameters in the ABCD grading system did not show progression in the post?CXL period, and parameters C and D showed improvement and stability a year after the procedure.

Prophylactic corneal crosslinking in myopic small-incision lenticule extraction - Long-term visual and refractive outcomes

Purpose: To analyze the efficacy, safety, predictability, and stability in myopic and astigmatic small?incision lenticule extraction (SMILE) with simultaneous prophylactic corneal crosslinking (CXL) in thin corneas. Methods: A total of 48 eyes from 24 patients who underwent myopic and astigmatism SMILE with simultaneous prophylactic CXL were included in this retrospective study. All patients had a 24?month follow?up. A femtosecond laser was performed with VisuMax (Carl Zeiss Meditec). CXL treatment was applied when the predicted stromal thickness was less than 330 ?m. Results: The patients’ mean age was 31.58 ± 6.23 years. The previous mean spherical equivalent was ? 6.85 ± 1.80 (?9.75 to ? 2.00) D. The postoperative mean spherical equivalent was ? 0.50 ± 0.26 (?1.00 to + 0.25) D; 60% of the eyes had 20/20 or better; 19% lost one line; 58% were within ± 0.50 D; and 8.3% of the eyes changed 0.50 D or more between 3 and 24 months. Conclusion: Prophylactic CXL with simultaneous SMILE for myopia and astigmatism femtosecond laser surgery technique appears to be partially effective, safe, predictable, and stable after 24 months of follow?up

Clinical observation on transepithelial rapid cross-linking combined with RGPCL in the treatment of keratoconus / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the clinical effect of transepithelial rapid cross-linking combined with wearing rigid gas permeable contact lens(RGPCL)in keratoconus patients.<p>METHODS: This was a retrospective study of patients with progressive keratoconus diagnosed in the Second Affiliated Hospital of Fujian University of Traditional Chinese Medicine in October 2014, and underwent transepithelial rapid keratoplasty. After surgery 16 patients(25 eyes)used RGPCL. Average age was 25.31±5.92 years old, maximum preoperative corneal curvature was 58.96±6.76D, thinnest corneal thickness was 439.52±53.24μm. Rapid cross-linking was performed using riboflavin and 45mW/cm² ultraviolet light(UV)irradiation with a total energy of 7.2J/cm². RGPCL was used after surgery. Follow up of 3-6a, average follow-up time was 52.44±11.39mo. The best corrected visual acuity \〖(BCVA), in RGPCL\〗, corneal curvature of flat meridian(K₁), corneal curvature of steep meridian(K₂), maximum corneal curvature(Kmax), corneal refractive power(MPP), Baiocchi Calossi Versaci index of anterior and posterior surface(BCVf and BCVb)asymmetry index of anterior surface curvature(SIf), asymmetry index of posterior surface curvature(SIb), the highest point of anterior cone cornea(KVf), the highest point of posterior cone cornea(KVb), the change of corneal thickness(ThkMin), lens opacity, and corneal endothelial cell count were observed.<p>RESULTS: All patients had a successful operation, and no intraoperative complications. On the first day after surgery, all cases felt slight tingling and slight photophobia tears. After 1d of operation, the corneal epithelium was removed in two eyes. While 3d after re-wearing the bandage, the epithelium healed. None of lens in the patients was opacified during follow-up, and there was no significant difference in corneal endothelial cell count compared with preoperative(<i>P</i>>0.05). The BCVA(wearing RGPCL)after operation is obviously improved compared with preoperative. All postoperative Kmax, SIf, KVf, BCVf, BCVb were lower than preoperative(<i>P</i><0.05). <p>CONCLUSION: Transepithelial rapid corneal cross-linking combined with RGPCL is safe and effective in controlling the progress of keratoconus. And the long-term effect is stable.

Repeatability and comparison of Corvis ST parameters before and after accelerated transepithelial corneal cross-linking in keratoconus eyes / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To evaluate the repeatability and comparison of corneal visualization scheimpflug technology(Corvis ST)parameters in keratoconus eyes before and after accelerated transepithelial corneal cross-linking(ATE-CXL).<p>METHODS: Thirty eyes of 30 progressive keratoconus patients were included in the prospective study. Three repeated corneal biomechanical measurements were performed preoperatively and one month postoperatively by Corvis ST. The interclass correlation coefficient(ICC)and 95% confidence interval(<i>CI</i>), Cronbach'α, repeatability coefficient(RC), and coefficient of variation(CV)were used to evaluate the repeatability of Corvis ST parameters. Paired <i>t</i>-test or Wilcoxon rank test was used to evaluate the differences between preoperative and postoperative data.<p>RESULTS: At preoperative, 26 of 39(66.67%)parameters showed good to excellent repeatability, 6(15.38%)showed moderate, and 7(17.95%)showed poor repeatability. Similarly, 34(87.18%)parameters showed good to excellent repeatability, 3(7.69%)showed moderate, and 2(5.13%)showed poor repeatability after ATE-CXL. After ATE-CXL 1mo, the intraocular pressure(IOP), biomechanical corrected IOP(bIOP), first applanation time(A1T), Radius, deformation amplitude at the first applanation(A1DA), deflection length at the maximum deformation(HCDLL)and stiffness parameter at first applanation(SP A1)parameters increased, while the steep keratometry(Ks), flat keratometry(Kf), mean keratometry(Kmean), second applanation time(A2T), DA Ratio Max(2 mm)and integrated radius parameters decreased(all <i>P</i><0.05). <p>CONCLUSION:The repeatability of the Corvis ST parameters before and 1mo ATE-CXL follow up were both acceptable, and the corneal stiffness was improved after 1mo ATE-CXL.

Effect of accelerated corneal crosslinking on ocular response analyzer waveform-derived parameters in progressive keratoconus / Efeito do crosslimking corneano acelerado nos parâmetros derivados da forma de onda do analisador de resposta ocular no ceratocone progressivo

ABSTRACT Purpose: To evaluate the effect of accelerated corneal crosslinking on corneal biomechanics with an ocular response analyzer in patients with progressive keratoconus. Methods: In this retrospective study, 50 eyes of 45 patients with progressive keratoconus who underwent accelerated corneal crosslinking were evaluated with ocular response analyzer waveform parameters before and one year after corneal crosslinking. Paired two-tailed Student's t-test was performed to compare the parameters before vs. after corneal crosslinking. Results: Mean patient age was 17.6 ± 3.6 (range 9-25) years. A significant increase was observed in p1 area, p2 area, h2, and dive2 values. No significant difference in corneal hysteresis, corneal resistance factor, or other waveform-derived parameters was observed at one year postoperatively. Conclusion: For estimating the effect of accelerated corneal crosslinking on corneal biomechanics, parameters such as p1 area, p2 area, h2, and dive2 are more sensitive than corneal hysteresis and corneal resistance factor. These results may help us to find out which corneal crosslinking method is most effective for stiffening the cornea.

RESUMO Objetivo: Avaliar o efeito do cross-linking corneano acelerado na biomecânica corneana com analisador de resposta ocular em pacientes com ceratocone progressivo. Métodos: Neste estudo retrospectivo, 50 olhos de 45 pacientes com ceratocone progressivo submetidos à cross-linking corneano acelerado foram avaliados com os parâmetros da forma de onda do analisador de resposta ocular antes e um ano após o tratamento com cross-linking corneano. O teste t de Student pareado bicaudal foi realizado para comparar os parâmetros antes e depois do cross-linking corneano. Resultados: A média de idade dos pacientes foi de 17,6 ± 3,6 (variação de 9 a 25) anos. Um aumento significativo foi observado nos valores de p1area, p2area, h2 e dive2. Nenhuma diferença significativa foi encontrada na histerese da córnea, fator de resistência da córnea ou outros parâmetros derivados da forma de onda foi observada em um ano de pós-operatório. Conclusão: Para estimar o efeito do cross-linking corneano acelerado na biomecânica corneana, parâmentros como p1area, p2area, h2 e dive2 são mais sensíveis que histerese da córnea e fator de resistência corneana. Esses resultados podem nos ajudar a descobrir qual método cross-linking corneano é mais eficaz no enrijecimento da córnea.

Long-term Results of Mini Asymmetric Radial Keratotomy and Corneal Cross-linking for the Treatment of Keratoconus

PURPOSE: To investigate the long-term results (at least 5 years of follow-up) of the mini asymmetric radial keratotomy (MARK) and corneal cross-linking (CXL) combined intervention, also known as the ‘Rome protocol,’ for patients with progressive stage I and II keratoconus and contact lens intolerance. METHODS: This was a retrospective observational case series. Fifteen eyes of 12 patients were evaluated, with a mean follow-up of 6.9 years. To assess the efficacy and stability of the MARK + CXL combined protocol, best spectacle-corrected visual acuity, mean pachymetry, and mean keratometry were recorded preoperatively and at least 1, 3, and 5 years postoperatively. Statistical analysis was performed using the R platform and involved the Wilcoxon signed-rank and Kruskal-Wallis non-parametric tests. RESULTS: Best spectacle-corrected visual acuity improved for all patients, from 0.46 ± 0.69 logarithm of the minimum angle of resolution (20 / 60) to 0.15 ± 0.69 logarithm of the minimum angle of resolution (20 / 30, p = 0.0006), while mean pachymetry increased in 93% of patients, from 442.80 ± 61.02 to 464.50 ± 62.72 µm (p = 0.003). Lastly, mean keratometry improved in 87% of patients after 6.9 years of observation from 48.82 ± 5.00 to 43.25 ± 3.58 diopters (p = 0.008). No intraoperative or postoperative complications were observed. CONCLUSIONS: The MARK + CXL combined protocol was effective in treating keratoconus by halting corneal thinning and bulging. In addition, this procedure significantly improved visual acuity based on long-term follow-up data. Analysis of data from a larger cohort of patients would be useful to support these findings.

Clinical efficacy of lamellar keratoplasty combined with acelerated corneal collagen cross-linking on refractory fungal corneal ulcer / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the efficacy of lamellar keratoplasty(LKP)combined with accelerated(45mW/cm2)corneal cross-linking(A-CXL)on refractory fungal corneal ulcer.<p>METHODS: Eighteen eyes of 18 patients with refractory fungal corneal ulcer were enrolled in the Department of Ophthalmology, First Affiliated Hospital of Jiangxi Medical College from January 2017 to November 2018. The postoperative visual acuity, corneal graft transparency, the incidence and prognosis of complications such as fungal recurrence, graft rejection, secondary glaucoma and complicated cataract were all recorded.<p>RESULTS: All the patients succeeded in avoiding enucleation or evisceration. Postoperatively, 16 eyes(89%)gained one or more lines in uncorrected distance visual acuity 2 eyes(11%)had unchanged in uncorrected distance visual acuity. Three eyes(17%)had a graft rejection. Secondary glaucoma were detected in 2 eyes(11%), and concomitant cataract were found in 3 eyes(17%). Thirteen eyes(72%)had transparent grafts, 4 eyes(22%)had translucent transects, and the remaining one eye(6%)had a turbid graft.<p>CONCLUSION: LK combined with A-CXL may be feasible for refractory fungal corneal ulcer treatment by improving the cure rate.

Results of accelerated trans - epithelial corneal collagen cross-linking protocol for the treatment of progressive keratoconus / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To report the long- term clinical outcomes of accelerated trans-epithelial corneal cross-linking ( CXL ) protocols using KXL System ( Avedro, USA ) in the treatment of progressive keratoconus. · METHODS: Totally 52 patients ( 102 eyes ) with progressive keratoconus between December 2014 and February 2017 [ maximum keratometry values ( Kmax) ≤60.0D, minimum corneal thickness(Thk) ≥400m] were treated with an accelerate trans-epithelial CXL protocol (UV-A irradiation intensity 45mW/cm2 with a total fluence of 7. 2J/cm2 ) using KXL system ( Avedro, USA ) in Southwest Hospital. The average follow-up time was 11. 65mo (range: 9-26mo). Uncorrected distance visual acuity ( UDVA) , corrected distance visual acuity ( CDVA) , intra- ocular pressure ( IOP ) , slit-lamp microscope examination, Kmax and average keratometry values ( AveK ) , corneal stromal demarcation line depth and endothelial cell density ( ECD) were evaluated. ·RESULTS:The 52 patients (102 eyes) were included in this research, male 36 (70 eyes) and female 16 (32 eyes), average age was 19. 5±4. 6 years. Preoperative CDVA was 0. 84±0. 89 (LogMAR), postoperative CDVA was 0. 69±0. 72 ( P = 0. 398 ). Preoperative UDVA was 1. 02 ± 0. 62 (LogMAR), postoperative UDVA was 0. 85 ± 0. 59 ( P =0. 154 ). Preoperative IOP was 12. 95 ± 4. 40mmHg, postoperative IOP was 11.92±3. 66mmHg (P=0. 272). No statistical difference (P=0. 552) has been found between preoperative and postoperative ECD. Nevertheless, on the Sirius anterior system ( Sirius, CSO, Itlay) , significant statistical difference (P=0. 017) was confirmed between preoperative Kmax ( 50. 83 ± 3. 48D ) and postoperative Kmax (52. 05±3. 63D). Meanwhile, the postoperative Avek (47.74±2. 51D) was significantly lower (P=0. 041) than the preoperative Avek ( 48. 73 ± 4. 33D ). The average corneal stromal demarcation line depth ( 192 ± 23. 6μm ) was detected by the anterior segment OCT. No statistical difference ( P = 0. 816 ) has been found between preoperative and postoperative Thk. No severe complication was observed in all cases. ·CONCLUSION: Accelerated trans-epithelial CXL was effective in decreasing keratometry values for progressive keratoconus in this research, and the outcomes remained stable during the follow-up time. No endothelium damage or other severe complications were observed in this clinical research. The accelerated trans-epithelial CXL is as effective as the standard CXL.

Comparison of corneal thickness reduction after corneal crosslinking in three different protocols / 眼科新进展

Objective To evaluate the differences of the thinnest-point corneal thickness (TCT) decrease after three different corneal crosslinking (CXL) protocols for progressive keratoconus.Methyds Retrospective clinical case study.From August 2010 to November 2015,consecutive 85 patients (110 eyes) with progressive keratoconus were enrolled and treated with CXL in Department of Opthalmology,Navy General Hospital.21 patients of 25 eyes underwent standard epithelium-off corneal crosslinking (S-CXL),14 patients of 22 eyes underwent 1 g · L-1 riboflavin-sodium lactate Ringer's solution iontophoresis-assisted CXL (I-CXLa),and 50 patients of 63 eyes underwent 0.1％ riboflavin-distilled water solution I-CXLb.Preoperative and postoperative TCT were measured by ALLEGRO oculyzer.The differences of TCT decrease after treatment were compared among the three CXL protocols.Results The differences of TCT from baseline after 3 months,6 months and 12 months in the S-CXL group were (-14.93 ±27.16) μm,(-31.94 ±22.89) μm,(-27.71 ±26.01) μm,respectively,the I-CXLa group were (-20.14 ± 19.09) μm,(-10.10 ± 24.28) μm,(-7.11 ± 22.26)μm,respectively,the I-CXLb group were (-28.08 ± 26.14) μm,(-21.08 ± 25.62) μm,(-15.91 ± 19.19)μm,respectively.Three months after treatment,the differences of TCT decrease in the three groups was not statistically significant (P =0.188);Six and 12 months after treatment,the differences between S-CXL and I-CXLa were statistically significant (all P ＜0.05),but the differences between S-CXL and I-CXLb,between I-CXLb and I-CXLa showed no significant difference (all P ＞ 0.05).Conclusion Six and 12 months after treatment,TCT decrease is related to the CXL protocol.TCT decrease degree may reflect the intensity of crossinking.TCT decrease in I-CXLb is smaller than that in S-CXL,but there is no statistical difference.

Tratamiento de queratitis micótica con voriconazol y crosslinking corneal: reporte de un caso / Successful treatment of fungal keratitis with voriconazole and crosslinking: a case report

La queratitis micótica es una causa importante de morbilidad y discapacidad visual, especialmente en los países en vía de desarrollo. Se considera una entidad de difícil manejo, con evolución usualmente tórpida, debido a diversos factores, dentro de los cuales destacan la agresividad de la infección, la dificultad para orientar una terapia basada en los resultados de las pruebas microbiológicas, la ausencia de un protocolo terapéutico estandarizado respaldado por estudios con buen nivel de evidencia, que garantice cubrimiento adecuado contra todos los tipos de hongos, disminucíon de la progresión de la infección, y mejoría clínica. Actualmente ante la presencia de casos con evolución tórpida tras el manejo médico se recurre a otras asociaciones en busca de buenos resultados, es ahí donde juega un papel importante el uso de crosslinking corneal como terapia adyuvante en el manejo de casos refractarios o que no tengan una adecuada evolución con la terapia habitual tópica. Presentamos el caso de un paciente joven de sexo masculino, quien fue tratado exitosamente con una terapia combinada consistente en Voriconazol tópico, sistémico y ante la no adecuada respuesta, se recurrió a un crosslinking corneal, lo cual se encuentra en concordancia con diversos reportes y estudios publicados en la literatura, que sugieren que el Voriconazol combinado con crosslinking corneal, podrían ser considerados una alternativa eficiente en el manejo de casos difíciles o que no tengan buena respuesta a la terapia antimicótica tradicional, teniendo en cuenta que aún hay mucho por investigar en este campo.

Fungal keratitis is an important cause of morbidity and visual disability primarily in developing countries. It is considered as a difficult to manage entity, usually with a torpid progression due to various factors, among these factors are the aggressiveness of the infection, the difficulty for orienting a therapy based on the results of the microbiological tests, the absence of a standardized therapeutic protocol backed by studies with a good level of evidence that guarantees adequate covering against all types of fungus, reduction of the infection progression and clinical improvement. Currently in response to cases with torpid progression after medical management you resort to other combinations in search of good results, this is where the use of corneal crosslinking plays an important role as adjuvant therapy in the treatment of refractory cases or in those cases that don´t have an adequate progress with the habitual topical therapy. We hereby present the case of a male young patient who was successfully treated with a combined therapy consisting of topic Voriconazole, systemic and in the presence of a non-adequate response, we resorted to a corneal crosslinking, which is in line with different reports and studies published in the literature that suggest that the Voriconazole combined with corneal crosslinking might be considered as an effective alternative in the treatment of intractable cases or cases that do not have a good response to the traditional antifungal therapy, bearing in mind that there is still too much research to be done in this field.

Newer protocols and future in collagen cross-linking.

Corneal Cross-Linking (CXL) is an established surgical procedure for the treatment of corneal disorders such as corneal ectasia and keratoconus. This method of treatment stabilises the corneal structure and increases rigidity, reducing the requirement for corneal transplantation. Since its development, many scientific studies have been conducted to investigate ways of improving the procedure. Biomechanical stability of the cornea after exposure to UV-A light, and the effect of shortening procedure time has been some of the many topics explored.

The theory and art of corneal cross-linking.

Before the discovery of corneal cross-linking (CXL), patients with keratoconus would have had to undergo corneal transplantation, or wear rigid gas permeable lenses (RGPs) that would temporarily flatten the cone, thereby improving the vision. The RGP contact lens (CL) would not however alter the corneal stability and if the keratoconus was progressive, the continued steepening of the cone would occur under the RGP CL. To date, the Siena Eye has been the largest study to investigate long term effects of standard CXL. Three hundred and sixty-three eyes were treated and monitored over 4 years, producing reliable long-term results proving long-term stability of the cornea by halting the progression of keratoconus, and proving the safety of the procedure. Traditionally, CXL requires epithelial removal prior to corneal soakage of a dextran-based 0.1% riboflavin solution, followed by exposure of ultraviolet-A (UV-A) light for 30 min with an intensity of 3 mW/cm2. A series of in vitro investigations on human and porcine corneas examined the best treatment parameters for standard CXL, such as riboflavin concentration, intensity, wavelength of UV-A light, and duration of treatment. Photochemically, CXL is achieved by the generation of chemical bonds within the corneal stroma through localized photopolymerization, strengthening the cornea whilst minimizing exposure to the surrounding structures of the eye. In vitro studies have shown that CXL has an effect on the biomechanical properties of the cornea, with an increased corneal rigidity of approximately 70%. This is a result of the creation of new chemical bonds within the stroma.

Anterior Elevation Changes Following Corneal Crosslinking for Keratoconus

PURPOSE: To report the results according to anterior elevation changes following corneal crosslinking (CXL) treatment for keratoconus. METHODS: The present retrospective study included 14 patients (15 eyes) with progressive keratoconus who underwent CXL with a follow-up of 12 months. Patients were classified into 2 groups according to pre and postoperative anterior elevation difference maps. On the preoperative anterior elevation map, distances from maximum anterior elevation to pupil center were compared between the 2 groups. The outcome of best correct visual acuity (BCVA), maximum keratometry and parameters of corneal topography were compared between the 2 groups before CXL as well as 6 and 12 months after CXL. RESULTS: The anterior elevation changes were classified as group 1 (-7.88 +/- 10.53 micrometer) or group 2 (8.71 +/- 5.99 micrometer) (p = 0.001). The preoperative corneal topography of eyes observed in group 1 (0.19 +/- 0.13 mm) had shorter mean distances from maximum anterior elevation to pupil center than eyes in group 2 (0.47 +/- 0.23 mm) (p = 0.018). BCVA (log MAR) improved from 0.68 +/- 0.78 to 0.57 +/- 0.81 (p = 0.115) 12 months after CXL in group 1 and decreased from 0.51 +/- 0.34 to 0.56 +/- 0.38 (p = 0.109) 12 months after CXL in group 2. The maximum keratometry decreased from 63.01 +/- 19.07D to 58.95 +/- 16.32D (p = 0.017) in group 1 and increased from 60.70 +/- 9.46D to 61.29 +/- 7.51D (p = 0.674) in group 2. CONCLUSIONS: Clinical and optical effects improved postoperatively in group 1, and were stabilized in group 2. The preoperative distance from maximum anterior elevation to pupil center and the anterior elevation changes after CXL were factors in predicting the CXL outcome.

Corneal Crosslinking in Far-Advanced Keratoconus

PURPOSE: To report 2 cases of far-advanced keratoconus with a high value of maximum keratometry and very thin corneas treated with corneal crosslinking (CXL). CASE SUMMARY: The thinnest corneal thickness of an 18-year-old woman with maximum keratometry of 106.5 D (case 1) was 335 microm. The thinnest corneal thickness of a 43-year-old man with maximum keratometry of 120.3 D (case 2) was 345 microm. The two cases underwent a customized topography and pachymetry-guided epithelial debridement technique to preserve the epithelium where the cornea was within 2 mm around the cone and subsequent CXL. Postoperative maximum keratometry was 97.2 D 24 months after CXL in case 1 and 109.3 D 18 months after CXL in case 2. Postoperatively, the thinnest corneal thickness was 343 microm in case 1 and 162 microm in case 2. The corneal thickness in case 1 was stabilized during the follow-up examination. The pupil center and apex of the corneal thickness in case 2 with the higher maximum keratometry was stabilized, but the thinnest corneal thickness was decreased immediately after CXL and did not recover before CXL. CONCLUSIONS: CXL was performed in 2 cases of far-advanced keratoconus. Results showed reduced maximum keratometry but, variable values in corneal thickness during the follow-up examination in the 2 cases. Longer follow-up is necessary, and CXL should be performed cautiously, especially for patients with far-advanced keratoconus.