Comparative evaluation of progression rate in keratoconus before and after collagen crosslinking

Posted Posted in cornea

progression, keratoconus, collagen, crosslinking

2017 Nov 9. pii: bjophthalmol-2017-311017. doi: 10.1136/bjophthalmol-2017-311017. [Epub ahead of print]

Comparative evaluation of progression rate in keratoconus before and after collagen crosslinking.

Abstract

PURPOSE:

To compare the rate of disease progression in keratoconus before and after corneal collagen crosslinking (CXL).

METHODS:

145 eyes were followed without CXL (no-CXL group) for a median duration of 31 months whereas 45 eyes were followed up for 41 months before (pre-CXL) and after (post-CXL) accelerated, epithelium-off crosslinking. Progression was defined based on significant slope found in linear mixed effect models against time. Swept-source optical coherence tomography was used for measurement of anterior steep keratometry, anterior flat keratometry (Ant Kf), anterior average keratometry (Ant Avg K); posterior steep keratometry, posteriorflat keratometry (Post Kf), posterior average keratometry (Post Avg K) and corneal thickness.

RESULTS:

The patients in pre-CXL group were significantly younger (26.3±5.48 years) compared with the patients in no-CXL group (32.7±10.24 years) (P=0.004). Significant differences were observed during baseline examination for all parameters (P≤0.035) between pre-CXL and no-CXL groups except Ant Cyl and Post Cyl. During observation period, statistically significant differences were noted between pre-CXL and no-CXL groups in the progression rate of Ant Kf, Ant Avg K, Post Kf and Post Avg K (P≤0.045). After CXL, the progression rate in post-CXL group was comparable to that in no-CXL group. All corneal parameters remained stable in no-CXL group throughout the follow-up period.

CONCLUSIONS:

Serial tomographic examination is useful to document disease progression before and after CXL. In our study, a decrease in progression rate of corneal parameters was noted after CXL. In cases with stable corneal parameters over time, careful monitoring can be considered instead of collagen crosslinking.

progression, keratoconus, collagen, crosslinking:

cornea; imaging; treatment other

PMID:
29122823
DOI:
10.1136/bjophthalmol-2017-311017

Effect of Cornea Preservation Time on Success of Descemet Stripping Automated Endothelial Keratoplasty: A Randomized Clinical Trial

Posted Posted in cornea

Cornea Preservation, Descemet Stripping Automated Endothelial Keratoplasty

2017 Nov 10. doi: 10.1001/jamaophthalmol.2017.4989. [Epub ahead of print]

Effect of Cornea Preservation Time on Success of Descemet Stripping Automated Endothelial Keratoplasty: A Randomized Clinical Trial.

Abstract

IMPORTANCE:

Demonstrating that success of Descemet stripping automated endothelial keratoplasty is similar across donor cornea preservation times (PTs) could increase the donor pool.

OBJECTIVE:

To determine whether the 3-year rate of graft success using corneal donor tissue preserved 8 to 14 days is noninferior to that of donor tissue preserved 7 days or less.

DESIGN, SETTING, AND PARTICIPANTS:

A multicenter, double-masked, randomized noninferiority clinical trial was conducted from April 16, 2012, to June 5, 2017, at 40 clinical sites (70 surgeons) in the United States, with donor corneas provided by 23 US eye banks. A total of 1090 individuals (1330 study eyes) underwent Descemet stripping automated endothelial keratoplasty (1255 eyes [94.4%] for Fuchs endothelial corneal dystrophy).

INTERVENTIONS:

Descemet stripping automated endothelial keratoplasty with random assignment of a donor cornea with a PT of 7 days or less (0-7d PT) or 8 to 14 days (8-14d PT).

MAIN OUTCOMES AND MEASURES:

Graft success at 3 years.

RESULTS:

Of the 1090 participants (1330 study eyes; 60.2% women and 39.8% men; median age at enrollment, 70 years [range, 42-90 years]), the 3-year cumulative probability of graft success was 95.3% (95% CI, 93.6%-96.9%) in the 0-7d PT group and 92.1% (95% CI, 89.9%-94.2%) in the 8-14d PT group (difference, 3.2%). The upper limit of the 1-sided 95% CI on the difference was 5.4%, exceeding the prespecified noninferiority limit of 4%. The difference was mostly owing to more primary donor failures in the 8-14d PT group, with the conditional probability of failure after the first month being 2.4% in the 0-7d PT group and 3.1% in the 8-14d PT group. In preplanned secondary analyses, longer PT was associated with a lower rate of graft success (unadjusted hazard ratio for graft failure per additional day of PT, 1.10; 95% CI, 1.03-1.18; P = .008 [PT analyzed as days]), with success rates of 96.5% (95% CI, 92.3%-98.4%) for PT of 4 days or less, 94.9% (95% CI, 92.5%-96.6%) for PT of 5 to 7 days, 93.8% (95% CI, 91.0%-95.8%) for PT of 8 to 11 days, and 89.3% (95% CI, 84.4%-92.7%) for PT of 12 to 14 days (P = .01 [PT analyzed as categorical variable]).

CONCLUSIONS AND RELEVANCE:

The 3-year success rate in eyes undergoing Descemet stripping automated endothelial keratoplasty was high irrespective of PT. However, the study was unable to conclude that the success rate with donor corneas preserved 8 to 14 days was similar to that of corneas preserved 7 days or less with respect to the prespecified noninferiority limit. Although longer PT was associated with a lower success rate, the difference in rates was small when PT was less than 12 days.

Cornea Preservation, Descemet Stripping Automated Endothelial Keratoplasty REGISTRATION:

clinicaltrials.gov Identifier: NCT01537393.

PMID:
29127431
DOI:
10.1001/jamaophthalmol.2017.4989

Comparison of central corneal thickness with four different optical devices

Posted Posted in cornea

corneal thickness, optical devices

2017 Oct 11. doi: 10.1007/s10792-017-0736-7. [Epub ahead of print]

Comparison of central corneal thickness with four different optical devices.

Abstract

BACKGROUND:

To compare the consistency between the average scores of the contact central corneal thickness measurements from ultrasound pachymetry devices still gold standard, such as iPac® and Echoscan US-500, and noncontact measurements via Pentacam HR and Sirius topography.

METHODS:

This prospective study, subsequently admitted to the ophthalmology department, 76 healthy individuals were performed. The measurements were repeated three times for each eye, and average scores were statistically analyzed on the same day and almost at the same time. While measuring the eyes, Pentacam HR, Sirius topography, iPac®, and Echoscan US-500 were used, respectively. The inter-rater agreement of measurements from the devices was assessed with intraclass correlation coefficient, and 95% Confidence Interval and p values demonstrating statistically significance were also presented. In the graphical assessment of the agreement, the Bland-Altman graph was used.

RESULTS:

Among 76 study participants, 43 (56.6%) were composed of women, and age level was 38.6 ± 12.5 years, ranging between 18 and 69. It was observed that the highest agreement was between the measurements obtained from Echoscan US-500 and iPac® devices, but the agreement between the measurements of different devices was higher than 0.90. Bland-Altman graphics were also investigated; the results of four different devices were seen to be consistent with one another.

CONCLUSIONS:

Therefore, the devices we compared in the study can be used as alternatives to one another due to the higher consistency between CCT measurements provided with through UP devices of Echoscan US-500 and iPac®, and Pentacam HR and Sirius topography devices.

CLINICAL TRIAL REGISTRATION NUMBER:

2016/112.

corneal thickness, optical devices

KEYWORDS:

Central corneal thickness; ,®

PMID:
29022163
DOI:
10.1007/s10792-017-0736-7

Meta-Analysis of Postoperative Outcome Parameters Comparing Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty

Posted Posted in cornea
Analysis,Postoperative,Descemet Membrane Endothelial Keratoplasty, Descemet Stripping Automated Endothelial Keratoplasty
2017 Sep 26. doi: 10.1097/ICO.0000000000001384. [Epub ahead of print]

Meta-Analysis of Postoperative Outcome Parameters Comparing Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty.

Abstract

PURPOSE:

This meta-analysis compares Descemet membrane endothelial keratoplasty (DMEK) with Descemet stripping automated endothelial keratoplasty (DSAEK) to evaluate their strength and weakness profiles.

DESIGN:

Meta-analysis.

METHODS:

We performed a meta-analysis and searched the peer-reviewed literature in PubMed, Cochrane Library, Web of Science, and Embase following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Prospective and retrospective trials performing and comparing DMEK and DSAEK were included. Effects were calculated as odds ratios or standardized mean differences.

RESULTS:

A total of 11 studies with a total of 723 eyes (350 DMEK and 373 DSAEK) were included. No significant difference was found regarding the total detachment rate, graft failure, and rejection. One of 340 eyes undergoing DMEK showed total detachment and 5 of 363 eyes undergoing DSAEK showed total detachment (P = 0.28). Six of 280 eyes undergoing DMEK showed graft failure; 1 of 313 eyes undergoing DSAEK developed this complication (P = 0.18). No rejection was observed in 158 eyes undergoing DMEK; 4 cases of rejection occurred in 196 eyes undergoing DSAEK (P = 0.37). No significant difference was found regarding endothelial cell loss (P = 0.48). There was a significantly higher partial detachment rate with DMEK: 88 of 340 eyes undergoing DMEK showed partial detachment; 16 of 363 eyes undergoing DSAEK showed this complication (P < 0.00001). DMEK was superior in best-corrected visual acuity after 6 months (P < 0.001), subjective evaluation of visual acuity (P = 0.001), patient satisfaction (P < 0.001), and was the method preferred by patients (P = 0.001).

CONCLUSIONS:

DMEK and DSAEK have a similar complication profile. However, the superiority in the visual outcome and patient satisfaction makes DMEK the preferred option for most patients.

Analysis,Postoperative,Descemet Membrane Endothelial Keratoplasty, Descemet Stripping Automated Endothelial Keratoplasty

 

PMID:
28957976
DOI:
10.1097/ICO.0000000000001384

Comparison of 5% Sulfur Hexafluoride Versus 100% Air Tamponade in Descemet Membrane Endothelial Keratoplasty

Posted Posted in cornea

 5% Sulfur Hexafluoride,100% Air Tamponade , Descemet Membrane Endothelial Keratoplasty

2017 Jul 24. doi: 10.1097/ICO.0000000000001299. [Epub ahead of print]

Comparison of 5% Sulfur Hexafluoride Versus 100% Air Tamponade in Descemet Membrane Endothelial Keratoplasty.

Abstract

PURPOSE:

To compare the rebubbling rate and clinical outcomes of Descemet membrane endothelial keratoplasty (DMEK) with 5% sulfur hexafluoride (SF6) gas versus 100% air as a tamponade for graft attachment.

METHODS:

Retrospective, comparative, interventional case series including 368 consecutive pseudophakic eyes with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy that underwent DMEK in a tertiary referral center between October 2010 and August 2015 using either air (group 1, 191 eyes) or 5% SF6 (group 2, 177 eyes) as a tamponade. The rebubbling rate, complications, best-corrected distance visual acuity (BCVA), manifest refraction, and endothelial cell density were analyzed before and at 1 week, 1, 3, 6, 12, 24, and 36 months after surgery.

RESULTS:

The rebubbling rate was 20.4% (39/191, group 1) versus 6.8% (12/177, group 2; P < 0.001). Complications included cystoid macular edema (n = 5, group 1, and n = 10, group 2; P = 0.14) and 1 case of presumed allograft rejection (n = 1, group 2). The follow-up period was 12 ± 8 months for group 1 and 6 ± 4 months for group 2. BCVA (logarithm of the minimum angle of resolution) had improved after 12 months from 1.43 ± 0.63 to 0.18 ± 0.26 (group 1, P < 0.001) and from 1.8 ± 0.63 to 0.18 ± 0.17 (group 2, P < 0.001). The percentage of eyes with BCVA ≥0.2 logarithm of the minimum angle of resolution at 12 months was 70.9% (90/127, group 1) and 78.4% (40/51, group 2; P = 0.3). Endothelial cell loss at 12 months after DMEK was 44 ± 18% (group 1) versus 33 ± 15% (group 2, P = 0.07).

CONCLUSIONS:

The use of a tamponade with 5% SF6 yielded a significantly lower incidence of graft detachment requiring surgical reintervention with no detrimental effect on graft endothelial cells. Thus, routine use of 5% SF6 for a graft tamponade in DMEK is recommended.

 5% Sulfur Hexafluoride,100% Air Tamponade , Descemet Membrane Endothelial Keratoplasty

PMID:
28742620

The percentage of eyes with BCVA ≥0.2 logarithm of the minimum angle of resolution at 12 months was 70.9% (90/127, group 1) and 78.4% (40/51, group 2; P = 0.3). Endothelial cell loss at 12 months after DMEK was 44 ± 18% (group 1) versus 33 ± 15% (group 2, P = 0.07).

CONCLUSIONS:

The use of a tamponade with 5% SF6 yielded a significantly lower incidence of graft detachment requiring surgical reintervention with no detrimental effect on graft endothelial cells. Thus, routine use of 5% SF6 for a graft tamponade in DMEK is recommended.

 5% Sulfur Hexafluoride,100% Air Tamponade , Descemet Membrane Endothelial Keratoplasty
 5% Sulfur Hexafluoride,100% Air Tamponade , Descemet Membrane Endothelial Keratoplasty
DOI:
10.1097/ICO.0000000000001299

Four-year Follow-up of the Changes in Anterior Segment After Phakic Collamer Lens Implantation

Posted Posted in Cataracts and Cataract Surgery, cornea
Anterior segment, phakic, collamer, lens implantation
Am J Ophthalmol. 2017 Jun;178:140-149. doi: 10.1016/j.ajo.2017.03.020. Epub 2017 Mar 23.

Four-year Follow-up of the Changes in Anterior Segment After Phakic Collamer Lens Implantation.

Author information

 Anterior segment, phakic, collamer, lens implantation

Abstract

PURPOSE:

To assess the changes and relationship in central vaulting, flare intensity, and crystalline lens thickness during a follow-up period of 4 years after implantable collamer lens (ICL) implantation in eyes with high myopia.

DESIGN:

Retrospective observational study.

METHODS:

Ninety-eight eyes of 50 patients were followed up with routine measurements of central vaulting, crystalline lens thickness, endothelial cell density, and aqueous flare postoperatively. Data were analyzed by repeated-measures analysis of variance. The relationship between the annual change in crystal lens thickness after surgery and age was evaluated by Pearson correlation coefficient and linear regression.

RESULTS:

There was a continuous reduction in central vaulting and endothelial cell density as well as an increase in crystalline lens thickness in ICL eyes from 1 month onward to 5 years postoperatively (P < .001). Although the trend of variation during the individual visit period was accentuated, the variation turned out to be smaller between 12 and 36 months or 60 months postoperatively (P = .42, P = .65). Aqueous flare intensity increased significantly after surgery and returned to normal 1 year later. Additionally, a positive correlation between patient age and crystalline lens thickness (r = 0.617, P < .0001) was observed in eyes with ICL implantation.

CONCLUSIONS:

The changes in central vaulting, endothelial cell density, and crystalline lens thickness are more prominent during the first year after ICL implantation, tending to be relatively stable afterwards. The anterior inflammation during the early postoperative period synchronizes with the sharp progression of crystalline lens changes within the first year.

Anterior segment, phakic, collamer, lens implantation
Not from article but Anterior segment, phakic, collamer, lens implantation

The Utility of Repeat Culture in Fungal Corneal Ulcer Management

Posted Posted in cornea
Repeat, Culture, Fungal, Cornea, Corneal Ulcer, Clinical Trial
Am J Ophthalmol. 2017 Jun;178:157-162. doi: 10.1016/j.ajo.2017.03.032. Epub 2017 Apr 4.

The Utility of Repeat Culture in Fungal Corneal Ulcer Management: A Secondary Analysis of the MUTT-I Randomized Clinical Trial.

Abstract

PURPOSE:

To determine whether patients who had a positive repeated culture was predictive of worse clinical outcome than those who achieved microbiological cure at 6 days in the Mycotic Ulcer Treatment Trial I (MUTT-I).

DESIGN:

Secondary analysis from a multicenter, double-masked, randomized clinical trial.

METHODS:

setting: Multiple hospital sites of the Aravind Eye Care System, India.

STUDY POPULATION:

Patients with culture-positive filamentous fungal ulcers and visual acuity of 20/40 to 20/400 reexamined 6 days after initiation of treatment.

INTERVENTION:

Corneal scraping and cultures were obtained from study participants at day 6 after enrollment.

MAIN OUTCOME MEASURES:

We assessed 3-month best spectacle-corrected visual acuity (BSCVA), 3-month infiltrate/scar size, corneal perforation, and re-epithelialization rates stratified by culture positivity at day 6.

RESULTS:

Of the 323 patients with smear-positive ulcers enrolled in MUTT-I, 299 (92.6%) were scraped and cultured 6 days after enrollment. Repeat culture positivity was 31% (92/299). Among patients who tested positive at enrollment, those with positive 6-day cultures had significantly worse 3-month BSCVA (0.39 logMAR; 95% confidence interval [CI]: 0.24-0.44; P < .001), had larger 3-month scar size (0.39 mm; 95% CI: 0.06-0.73; P = .02), were more likely to perforate or require therapeutic penetrating keratoplasty (odds ratio: 6.27; 95% CI: 2.73-14.40; P < .001), and were slower to re-epithelialize (hazard ratio: 0.33; 95% CI: 0.21-0.50; P < .001) than those with a negative 6-day culture result.

CONCLUSIONS:

Early microbiological cure on culture is a predictor of clinical response to treatment.

PMID:
28385473
DOI:
10.1016/j.ajo.2017.03.032

Repeat, Culture, Fungal, Cornea, Corneal Ulcer, Clinical Trial

Collagen crosslinking with conventional and accelerated ultraviolet-A irradiation using riboflavin with hydroxypropyl methylcellulose

Posted Posted in cornea

Collagen crosslinking,ultraviolet, irradiation,riboflavin,methylcellulose

J Cataract Refract Surg. 2017 Apr;43(4):511-517. doi: 10.1016/j.jcrs.2017.01.013.

Collagen crosslinking with conventional and accelerated ultraviolet-A irradiation using riboflavin with hydroxypropyl methylcellulose.

Abstract

PURPOSE:

To evaluate corneal collagen crosslinking (CXL) with conventional and accelerated ultraviolet-A (UVA) irradiation using riboflavin with methylcellulose.

SETTING:

Department of Ophthalmology, Oslo University Hospital, Oslo, Norway.

DESIGN:

Prospective randomized case series.

METHODS:

Patients with keratoconus were randomized to have CXL using conventional 3 mW/cm2 UVA irradiation for 30 minutes (CXL30) or accelerated 9 mW/cm2 UVA irradiation for 10 minutes (CXL10). In both groups, a solution of riboflavin 0.1% with hydroxypropyl methylcellulose 1.1% (methylcellulose-riboflavin) was used. The endothelial cell density (ECD), visual acuity, and tomography were measured at baseline and after 12 months. Anterior segment optical coherence tomography and in vivo confocal microscopy (IVCM) were performed after 1 month.

RESULTS:

The study comprised 40 patients (40 eyes). A complete absence of keratocytes in all eyes at 100 μm depths was found on IVCM. At 300 μm, 400 μm, and preendothelial levels, the differences were 83.3% versus 31.3% (P = .02), 64.7% versus 20.0% (P = .01), and 42.1% versus 5.9% (P = .02) in the CXL30 and CXL10 groups. No statistically significant differences were found in the change in visual acuity or maximum keratometry between the groups after 12 months. There was no relationship between the depth of keratocyte absence and the ECD change after 12 months.

CONCLUSIONS:

Marked deep structural changes with an absence of keratocytes occurred when CXL was used with conventional or accelerated UVA irradiation; however, the changes were more pronounced with the use of conventional UVA irradiation. The use of methylcellulose-riboflavin might explain the deep alterations and raises a long-term safety concern.

PMID:
28532937
DOI:
10.1016/j.jcrs.2017.01.013

Guiding flying-spot laser transepithelial phototherapeutic keratectomy with optical coherence tomography

Posted Posted in cornea, lasik

 flying spot, laser, transepithelial, phototherapeutic keratectomy, optical coherence tomography

J Cataract Refract Surg. 2017 Apr;43(4):525-536. doi: 10.1016/j.jcrs.2017.03.004.

Guiding flying-spot laser transepithelial phototherapeutic keratectomy with optical coherence tomography.

Abstract

PURPOSE:

To analyze transepithelial phototherapeutic keratectomy (PTK) results using optical coherence tomography (OCT) and develop a model to guide the laser dioptric and depth settings.

SETTING:

Casey Eye Institute, Portland, Oregon, USA.

DESIGN:

Prospective nonrandomized case series.

METHODS:

Patients with superficial corneal opacities and irregularities had transepithelial PTK with a flying-spot excimer laser by combining wide-zone myopic and hyperopic astigmatic ablations. Optical coherence tomography was used to calculate corneal epithelial lenticular masking effects, guide refractive laser settings, and measure opacity removal. The laser ablation efficiency and the refractive outcome were investigated using multivariate linear regression models.

RESULTS:

Twenty-six eyes of 20 patients received PTK to remove opacities and irregular astigmatism due to scar, dystrophy, radial keratotomy, or previous corneal surgeries. The uncorrected distance visual acuity and corrected distance visual acuity were significantly improved (P < .01) by 3.7 Snellen lines and 2.0 Snellen lines, respectively, to a mean of 20/41.2 and 20/22.0, respectively. Achieved laser ablation depths were 31.3% (myopic ablation) and 63.0% (hyperopic ablation) deeper than the manufacturer’s nomogram. The spherical equivalent of the corneal epithelial lenticular masking effect was 0.73 diopter ± 0.61 (SD). The refractive outcome highly correlated to the laser settings and epithelial lenticular masking effect (Pearson R = 0.96, P < .01). The ablation rate of granular dystrophy opacities appeared to be slower. Smoothing ablation under masking fluid was needed to prevent focal steep islands in these cases.

CONCLUSIONS:

The OCT-measured ablation depth efficiency could guide opacity removal. The corneal epithelial lenticular masking effect could refine the spherical refractive nomogram to achieve a better refractive outcome after transepithelial ablation.

Biomarkers and Endpoints for Dry Eye Clinical Research

Posted Posted in cornea
Biomarkers,Endpoints,Dry Eye, Clinical Research
Invest Ophthalmol Vis Sci. 2017 May 1;58(6):BIO1-BIO19. doi: 10.1167/iovs.17-21709.

The Growing Need for Validated Biomarkers and Endpoints for Dry Eye Clinical Research.

Biomarkers,Endpoints,Dry Eye, Clinical Research

Abstract

PURPOSE:

Biomarkers with minimally invasive and reproducible objective metrics provide the key to future paradigm shifts in understanding of the underlying causes of dry eye disease (DED) and approaches to treatment of DED. We review biomarkers and their validity in providing objective metrics for DED clinical research and patient care.

METHODS:

The English-language literature in PubMed primarily over the last decade was surveyed for studies related to identification of biomarkers of DED: (1) inflammation, (2) point-of-care, (3) ocular imaging, and (4) genetics. Relevant studies in each group were individually evaluated for (1) methodological and analytical details, (2) data and concordance with other similar studies, and (3) potential to serve as validated biomarkers with objective metrics.

RESULTS:

Significant work has been done to identify biomarkers for DED clinical trials and for patient care. Interstudy variation among studies dealing with the same biomarker type was high. This could be attributed to biologic variations and/or differences in processing, and data analysis. Correlation with other signs and symptoms of DED was not always clear or present.

CONCLUSIONS:

Many of the biomarkers reviewed show the potential to serve as validated and objective metrics for clinical research and patient care in DED. Interstudy variation for a given biomarker emphasizes the need for detailed reporting of study methodology, including information on subject characteristics, quality control, processing, and analysis methods to optimize development of nonsubjective metrics. Biomarker development offers a rich opportunity to significantly move forward clinical research and patient care in DED.

OVERVIEW:

DED is an unmet medical need – a chronic pain syndrome associated with variable vision that affects quality of life, is common with advancing age, interferes with the comfortable use of contact lenses, and can diminish results of eye surgeries, such as cataract extraction, LASIK, and glaucoma procedures. It is a worldwide medical challenge with a prevalence rate ranging from 8% to 50%. Many clinicians and researchers across the globe are searching for better answers to understand the mechanisms related to the development and chronicity of DED. Though there have been many clinical trials for DED, few new treatments have emerged over the last decade. Biomarkers may provide the needed breakthrough to propel our understanding of DED to the next level and the potential to realize our goal of truly personalized medicine based on scientific evidence. Clinical trials and research on DED have suffered from the lack of validated biomarkers and less than objective and reproducible endpoints. Current work on biomarkers has provided the groundwork to move forward. This review highlights primarily ocular biomarkers that have been investigated for use in DED, discusses the methodologic outcomes in providing objective metrics for clinical research, and suggests recommendations for further work.Biomarkers,Endpoints,Dry Eye, Clinical Research