Objective: To evaluate subclinical macular findings in premature patients at risk of retinopathy of prematurity (ROP) with the use of handheld spectral-domain optical coherence tomography (SD-OCT).Design: Prospective, observational case series.Particip…
Category: Peer-reviewed
Photodynamic Therapy Versus Combination Therapy in Polypoidal Choroidal Vasculopathy: Changes of Aqueous Vascular Endothelial Growth Factor – Corrected Proof
Purpose: To investigate the influence of photodynamic therapy (PDT) and combination of PDT and ranibizumab on aqueous humor levels of vascular endothelial growth factor (VEGF) in polypoidal choroidal vasculopathy (PCV).Design: Prospective randomized cl…
American Joint Committee on Cancer Classification of Posterior Uveal Melanoma (Tumor Size Category) Predicts Prognosis in 7731 Patients – Corrected Proof
Purpose: To evaluate the clinical features and prognosis of posterior uveal (ciliary body and choroid) melanoma based on the American Joint Committee on Cancer (AJCC) classification (7th edition) of primary tumor (T).Design: Retrospective, interventional case series.Participants: Seven thousand seven hundred thirty-one patients.Intervention: Ocular management including plaque radiotherapy, enucleation, local resection, or laser therapy.Main Outcome Measures: Melanoma-related metastasis and death.Results: Of 7731 patients with posterior uveal melanoma, the AJCC classification based on T was category T1 in 3557 (46%), T2 in 2082 (27%), T3 in 1599 (21%), and T4 in 493 (6%). Based on tumor categories T1, T2, T3, and T4, respectively, features that showed significant increase with tumor category included patient age at presentation (57, 58, 58, and 61 years; P<0.001), tumor base (8, 12, 15, and 20 mm; P<0.001), tumor thickness (3.5, 5.2, 8.9, and 11.4 mm; P<0.001), mushroom configuration (8%, 20%, 38%, and 39%; P<0.001), associated subretinal fluid (64%, 80%, 82%, and 83%; P<0.001), intraocular hemorrhage (5%, 12%, 17%, and 18%; P<0.001), rupture of Bruch’s membrane (9%, 24%, 40%, and 40%; P<0.001), and extraocular extension (1%, <1%, 4%, and 12%; P<0.001). After therapy, Kaplan-Meier estimates of metastasis at 5, 10, and 20 years were 8%, 15%, and 25% for category T1, 14%, 25%, and 40% for category T2, 31%, 49%, and 62% for category T3, and 51%, 63%, and 69% for category T4, respectively (P<0.001). Kaplan-Meier estimates of death at 5, 10, and 20 years were 4%, 8%, and 11% for category T1, 8%, 13%, and 24% for category T2, 19%, 27%, and 36% for category T3, and 30%, 43%, and 51% for category T4, respectively (P<0.001). Compared with category T1, the hazard ratio for metastasis and death for T2 was 1.8 and 1.9, respectively, that for T3 was 4.5 and 4.7, respectively, and that for T4 was 8.2 and 8.8, respectively.Conclusions: Based on the AJCC classification, increasing tumor category was associated with older age, larger tumor, and greater incidence of subretinal fluid, hemorrhage, and extraocular extension. Compared with uveal melanoma classified as T1, the rate of metastasis and death was 2 times greater for T2, 4 times greater for T3, and 8 times greater for T4. The risk for metastasis and death increased 2-fold with each increasing melanoma category.Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Impairment of Lacrimal Secretion in the Unaffected Fellow Eye of Patients with Recurrent Unilateral Herpetic Keratitis – Corrected Proof
Purpose: To assess the impact of recurrent unilateral herpetic keratitis (HK) on the tear secretion of the unaffected fellow eye.Design: Prospective, noninterventional study.Participants and Controls: Thirty-five patients with a history of recurrent unilateral HK (clinically quiescent for at least 3 months) (HK group) and 35 patients who were age- and sex-matched with no history of corneal disease (control group).Methods: Tear osmolarity, tear instability (tear break-up time [TBUT]), tear reflex (Schirmer’s I test), and central corneal sensitivity with the Cochet–Bonnet esthesiometer (Luneau, France) were measured in the HK and control groups.Main Outcome Measures: Tear osmolarity, TBUT, Schirmer’s I, and central corneal sensitivity were compared between the affected and unaffected eyes of the HK and control groups.Results: Tear osmolarity and tear secretion reflex were similar between the affected and unaffected eyes of the HK group. Corneal sensitivity and TBUT were statistically lower in the affected eyes compared with the unaffected eyes in the HK group (P = 0.001 and P<0.001, respectively). The central corneal sensitivity of unaffected eyes in the HK group was not significantly different from that in the control group (P>0.05). The tear stability and tear secretion reflex were decreased and tear osmolarity was increased in the unaffected eyes of the HK group compared with the control group (P<0.05, all cases). The difference between unaffected and control eyes varied according to the type of HK. All 4 tests were modified in patients with neurotrophic keratitis (KN). In the keratouveitis subgroup, only corneal sensitivity was normal, whereas Schirmer’s I results were also normal in patients with archipelago keratitis. Tear osmolarity was consistently affected in both eyes of herpetic patients.Conclusions: Tear function is impaired in the unaffected eyes of patients with unilateral recurrent HK, even when the disease is apparently quiescent. The higher severity of results in the unaffected fellow eye of patients with KN in comparison with other herpes subgroups suggests that recurrent HK induces a reduction in the afferent pathways of the tear secretion reflex from the affected eye, leading to tear dysfunction in the unaffected eye.Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Utility and Uncorrected Refractive Error – Corrected Proof
Purpose: To investigate utility (a preference-based quality of life [QoL] measure) associated with uncorrected refractive error (URE).Design: Cross-sectional study.Participants: A cohort of 341 consecutive patients 40 to 65 years of age with refractive error and no ocular disease impairing vision worse than 20/25 (0.1 logarithm of the minimum angle of resolution [logMAR] units) in the better eye. Without vision correction, 30 had no vision impairment, 65 had only distance vision impairment (DVI), 97 had only near vision impairment (NVI), 112 had moderate amounts of both distance and near vision impairment (DNVI), and 37 had severe impairment (distance or near worse than 20/200 [>1.0 logMAR]) in the better eye.Methods: All participants underwent a comprehensive eye examination with refraction, aided and unaided visual acuity (VA) at 6 m and 40 cm, and ocular health assessment. Utilities were elicited for a number of scenarios using a standardized, face-to-face time trade-off (TTO) interview method.Main Outcome Measures: The main outcome measure was TTO utility for the participant’s own uncorrected vision state. Utilities ranged from 0 to 1, where 0 = death and 1 = perfect vision, and were scaled to account for comorbidities so that 1 = perfect health (adjusted utility).Results: Unaided VA was 0.50±0.24 logMAR at distance in the DVI group, 0.43±0.17 logMAR at near in the NVI group, and 0.72±0.36 and 0.56±0.29 at distance and near, respectively, in the DNVI group. Adjusted utilities for the 3 groups were 0.82±0.16 in the DVI group, 0.81±0.17 in the NVI group, and 0.68±0.25 in the DNVI group. The DVI and NVI group utilities (adjusted and unadjusted) did not differ significantly (P = 0.73 and P = 0.77, respectively). The DNVI utility was significantly worse than that of the DVI and NVI groups (adjusted and unadjusted, P<0.01).Conclusions: The URE is associated with measurable reductions in utility (and therefore QoL). Reductions are similar regardless of whether near or distance vision is impaired, but worse when both are impaired. The results underscore the significance of the effect of URE on QoL, particularly with respect to uncorrected presbyopia, which has been a relatively neglected area in research and policy. The utility figures in this study can be used as inputs for cost-effectiveness studies relating to URE to assist resource allocation decisions.Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Analysis of Choroidal Morphologic Features and Vasculature in Healthy Eyes Using Spectral-Domain Optical Coherence Tomography – Corrected Proof
Objective: To analyze the morphologic features and vasculature of the choroid in healthy eyes using spectral-domain (SD) optical coherence tomography (OCT).Design: Cross-sectional retrospective review.Participants: Forty-two healthy subjects (42 eyes) …
Ocular Demodicosis as a Risk Factor of Pterygium Recurrence – Corrected Proof
Purpose: To evaluate ocular demodicosis as a potential risk factor in pterygium recurrence.Design: Cross-sectional study to correlate clinical findings with laboratory data.Participants: We retrospectively reviewed 94 patients (43 with primary and 51 with recurrent pterygia), among whom 68 patients received surgical correction, and prospectively enrolled another 23 pterygium patients and 14 nonpterygium controls for measuring the tear level of interleukin (IL)-17.Methods: All patients had microscopically confirmed ocular demodicosis. Statistical correlations were analyzed among age, sex, aqueous tear deficiency, dry eye, ocular demodicosis, follow-up period, surgical outcome, and tear levels of IL-17 measured by enzyme-linked immunosorbent assay.Main Outcome Measures: Correlation between ocular demodicosis or IL-17 levels and pterygium recurrence.Results: Among 94 patients, ocular demodicosis was more prevalent in patients with recurrent pterygium than those with primary pterygium (P = 0.015). During follow-up of 16.5±11.5 months, 68 postsurgical patients developed 7 corneal recurrences, which constituted 7.4% of primary and 12.2% of recurrent pterygium (P = 0.820). They also developed 8 conjunctival recurrences. Kaplan–Meier survival analysis showed combined (P = 0.000), corneal (P = 0.044), and conjunctival (P = 0.002) recurrence was significantly higher among patients with demodicosis than those without. Conjunctival recurrence occurred within 6 months in eyes without demodicosis but extended beyond 6 months in eyes with demodicosis. In 34 postsurgical patients with demodicosis, the mite count of 14 patients with recurrence was significantly higher than that of 20 without (P = 0.005). The IL-17 level was significantly higher in patients with either pterygium or demodicosis than controls (P = 0.049 and 0.040, respectively), and the IL-17 level was further elevated in patients with both pterygium and demodicosis (all P<0.05).Conclusions: Ocular demodicosis is a risk factor for pterygium recurrence, especially for conjunctival recurrence, presumably by perpetuating chronic inflammation mediated by T-helper (Th)17 lymphocytes.Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article.
Ocular Adnexal Lymphoma: Assessment of a Tumor-Node-Metastasis Staging System – Corrected Proof
Purpose: To assess distribution, correlations, and prognostic effect of tumor (T), node (N), and metastasis (M) staging on relapse and survival.Design: Retrospective clinical review.Participants: Sixty-three patients diagnosed with primary ocular adnex…
A Population-based Survey of the Prevalence and Types of Glaucoma in Central Iran: The Yazd Eye Study – Corrected Proof
Purpose: To describe the prevalence and types of glaucoma in Yazd, central Iran.Design: Population-based, cross-sectional study.Participants: Iranian adults aged 40 to 80 years, residing in Yazd, Iran, in 2010 and 2011.Methods: Eligible samples were s…
Correction of Visual Impairment by Cataract Surgery and Improved Survival in Older Persons: The Blue Mountains Eye Study Cohort – Corrected Proof
Objective: We assessed whether correction of visual impairment (VI) by cataract surgery was associated with improved long-term survival in an older Australian population.Design: Population-based cohort study.Participants: In the Blue Mountains Eye Study, 354 participants, aged ≥49 years, had both cataract and VI or had undergone cataract surgery before baseline examinations. They were subsequently examined after 5- and 10-year follow-ups.Methods: Associations between the mortality risk and the surgical correction of VI (visual acuity [VA] <20/40, attributable to cataract) were assessed in Cox proportional hazard regression models, after multivariate adjustment, using time-dependent variables for the study factor.Main Outcome Measures: All-cause mortality.Results: The 15-year crude mortality of participants who had undergone cataract surgery at baseline with no subsequent VI (71.8%) was relatively similar to that in participants with cataract-related VI who had not yet undergone surgery (79.4%). However, after adjusting for age and sex, participants who underwent cataract surgery before baseline or during follow-up and no longer had VI had significantly lower long-term mortality risk (hazard ratio [HR], 0.60; 95% confidence interval [CI], 0.46–0.77) than participants with VI due to cataract who had not undergone cataract surgery. This lower mortality risk in the group with surgically corrected VI (HR, 0.54; 95% CI, 0.41–0.73) persisted after further adjustment for smoking, body mass index, home ownership, qualifications, poor self-rated health, the presence of poor mobility, hypertension, diabetes, self-reported history of angina, myocardial infarction, stroke, cancer, asthma, and arthritis. This finding remained significant (HR, 0.55; 95% CI, 0.41–0.73) after additional adjustment for the number of medications taken (continuous variable) and the number (≥5 vs. <5) of comorbid conditions (poor mobility, hypertension, diabetes, angina, myocardial infarction, stroke, cancer, asthma, or arthritis) as indicators of frailty.Conclusions: Surgical correction of VI due to cataract was associated with significantly better long-term survival of older persons after accounting for known cataract and mortality risk factors, and indicators of general health. Whether some uncontrolled factors (frailty or general health) could have influenced decisions not to perform cataract surgery in some participants is unknown. However, this finding strongly supports many previous reports linking VI with poor survival.Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.
Subfoveal Fibrosis in Eyes With Neovascular Age-Related Macular Degeneration Treated With Intravitreal Ranibizumab – Corrected Proof
Purpose: To assess baseline and follow-up characteristics of choroidal neovascularization (CNV) lesions in age-related macular degeneration in relation to the development of subfoveal subretinal fibrosis.Design: Retrospective, observational case series…
Short-Term Outcomes of Aflibercept for Neovascular Age-Related Macular Degeneration in Eyes Previously Treated With Other Vascular Endothelial Growth Factor Inhibitors – Corrected Proof
Purpose: To report results of aflibercept therapy in eyes with neovascular age-related macular degeneration previously treated with bevacizumab, ranibizumab, or both.Design: Retrospective, interventional, noncomparative, consecutive case series.Methods…
Assessment of Retinal Function Before and After Idiopathic Macular Hole Surgery – Corrected Proof
Purpose: To evaluate preoperative and postoperative retinal function in patients who underwent macular surgery for idiopathic macular hole.Design: Prospective, comparative, interventional case series.Methods: Thirty eyes of 30 patients with idiopathic macular hole were included in the study. Patients underwent pars plana vitrectomy and peeling of the internal limiting membrane (ILM). ILM visualization was improved in 15 patients by using triamcinolone acetonide and in the remaining 15 patients by using infracyanine green dye. Spectral-domain optical coherence tomography examination was performed to document macular hole closure. Retinal function was assessed preoperatively and postoperatively over a period of 12 months by best-corrected visual acuity (BCVA) measurement (ETDRS chart), MP-1 microperimetry, and focal electroretinogram recording (fERG). Focal electroretinograms were recorded in response to a sinusoidally modulated (41 Hz), uniform field presented to the macular (18 degrees) and foveal (2.25 degrees) region.Results: Macular hole closure was achieved in all patients in both groups. At 12 months, visual acuity improved in both groups (P < .001), and there were no statistically significant differences between groups. Mean macular sensitivity within the central 2 and 8 degrees increased in both groups, and there were no statistically significant differences between groups at any follow-up. In the triamcinolone acetonide group, 12 months after surgery the amplitude of the fERG’s first harmonic (1F) increased both in the macular region (P < .001) and in the foveal region (P < .05). In the infracyanine green group, at 12 months the amplitude of the first harmonic (1F) decreased in both areas. The decrease was significant in the macular region (P < .05) and not significant in the foveal region (P = .095).Conclusion: Vitrectomy and ILM peeling assisted with either triamcinolone acetonide or infracyanine green staining improves visual acuity and mean macular sensitivity at 12 months in patients affected by idiopathic macular hole. However, triamcinolone acetonide staining is associated with an increase of fERG’s first harmonic amplitude in the foveal and macular region, whereas in the case of infracyanine green staining it seems to decrease after surgery. The reduction of the amplitude of fERG’s first harmonic suggests that infracyanine green may have a late toxic effect on photoreceptor cells.
Accuracy and Speed of Electronic Health Record Versus Paper-Based Ophthalmic Documentation Strategies – Corrected Proof
Purpose: To compare accuracy and speed of keyboard and mouse electronic health record (EHR) documentation strategies with those of a paper documentation strategy.Design: Prospective cohort study.Methods: Three documentation strategies were developed: (1) keyboard EHR, (2) mouse EHR, and (3) paper. Ophthalmology trainees recruited for the study were presented with 5 clinical cases and documented findings using each strategy. For each case-strategy pair, findings and documentation time were recorded. Accuracy of each strategy was calculated based on sensitivity (fraction of findings in actual case that were documented by subject) and positive ratio (fraction of findings identified by subject that were present in the actual case).Results: Twenty subjects were enrolled. A total of 258 findings were identified in the 5 cases, resulting in 300 case-strategy pairs and 77 400 possible total findings documented. Sensitivity was 89.1% for the keyboard EHR, 87.2% for mouse EHR, and 88.6% for the paper strategy (no statistically significant differences). The positive ratio was 99.4% for the keyboard EHR, 98.9% for mouse EHR, and 99.9% for the paper strategy (P < .001 for mouse EHR vs paper; no significant differences between other pairs). Mean ± standard deviation documentation speed was significantly slower for the keyboard (2.4 ± 1.1 seconds/finding) and mouse (2.2 ± 0.7 seconds/finding) EHR compared with the paper strategy (2.0 ± 0.8 seconds/finding). Documentation speed of the mouse EHR strategy worsened with repetition.Conclusions: No documentation strategy was perfectly accurate in this study. Documentation speed for both EHR strategies was slower than with paper. Further studies involving total physician time requirements for ophthalmic EHRs are required.
Use of a Comprehensive Polymerase Chain Reaction System for Diagnosis of Ocular Infectious Diseases – Corrected Proof
Purpose:
To measure the genomic DNA of ocular infectious pathogens in ocular fluids and to analyze the clinical relevance of these pathogens in uveitis and endophthalmitis.
Design:
Prospective clinical case series.
Participants:
A total of 500 pa…
Correction of Ocular Shape in Retinal Optical Coherence Tomography and Effect on Current Clinical Measures – Corrected Proof
Purpose: To address the misrepresentation of the eye in retinal optical coherence tomography (OCT) images and to examine the effect of this misrepresentation on retinal thickness measurements.Design: Prospective case series.Methods: Five subjects with recent orbital magnetic resonance imaging (MRI) scans and normal eye examinations were consented from the clinics of the Duke Eye Center. Each subject had both eyes imaged using a retinal spectral-domain OCT system and ocular biometry measured. Two types of individualized optical models of the subject eyes—numerical and analytical—were used to determine the spatial paths of the OCT A-scans. These paths were used to reorient the A-scans in the associated retinal OCT images and generate corrected images. Using curvature as a general measure of shape, the radii of curvature of the retinal pigment epithelium in the original and corrected OCT images were compared to the ocular radii of curvature in the MRI images. Differences between the retinal thickness maps derived from the original and corrected OCT images were then determined.Results: The retinal curvatures were substantially flatter in the original OCT than in the MRI images (mean paired difference: 52.8 ± 41.8 mm, P < .001). Correcting the OCT images decreased the paired differences between OCT and MRI (numerical: 1.6 ± 2.3 mm, P = .091; analytical: 1.9 ± 4.3 mm, P = .278). Retinal thickness measurements between the corrected and uncorrected images differed, with a root mean square difference of 5.61 μm over the entire 6-mm extent of the image; this difference was greater peripherally (6.02 μm) than centrally (2.54 μm).Conclusions: Optically based algorithms can be used to correct the shape of the retina as represented in OCT; this correction makes OCT more consistent with other clinical imaging techniques. Resultant retinal thickness maps were minimally affected by the change in shape. Ocular shape correction should be considered in future development of posterior segment OCT-based morphologic measurements.
Correction of Lower Lid Retraction Using TarSys Bioengineered Grafts for Graves Ophthalmopathy – Corrected Proof
Purpose: To investigate the efficacy of decellularized porcine-derived membrane (tarSys; IOP Inc), a bioengineered eyelid spacer graft, for lower lid retraction correction in patients with Graves ophthalmopathy.Design: Retrospective observational case series study.Methods: This was a retrospective review of patients with Graves ophthalmopathy undergoing lower eyelid retraction surgery using decellularized porcine-derived membrane bioengineered eyelid spacer grafts from 2008 through 2011. Outcome measures included lower eyelid height (measured from the corneal light reflex to the lower eyelid margin, or marginal reflex distance-2 [MRD2]), reduction of lagophthalmos, cosmetic appearance, complications, and need for further surgery. Presurgery and postreconstruction photographs were reviewed for functional and cosmetic outcome.Results: A total of 32 Graves patients and 37 eyelids underwent lower eyelid retraction surgery using decellularized porcine-derived membrane. There were 10 male and 22 female patients with mean age of 41.8 ± 8.6 years. Mean improvement in MRD2 was 1.4 ± 0.4 mm. Mean reduction of lagophthalmos was 1.3 ± 0.4 mm. There are statistically significant differences between preoperative and postoperative MRD2 and lagophthalmos (paired t test, both P < .0001). No evidence of infection and corneal erosion was noted and none of the patients needed further surgeries. Prolonged lower lid swelling and slight puffy appearance were noted for 6 patients. The swelling and puffy appearance resolved completely 3 months after surgery. Conjunctival granuloma formation was found in 1 patient. The cosmetic result was satisfactory in all cases.Conclusions: Decellularized porcine-derived membrane, a bioengineered graft, is effective for the management of lower lid retraction in patients with Graves ophthalmopathy. It can offer an alternate graft for eyelid reconstruction.
Seven-Year Outcomes in Ranibizumab-Treated Patients in ANCHOR, MARINA, and HORIZON: A Multicenter Cohort Study (SEVEN-UP) – Corrected Proof
Purpose: To assess long-term outcomes 7 to 8 years after initiation of intensive ranibizumab therapy in exudative age-related macular degeneration (AMD) patients.Design: Multicenter, noninterventional cohort study.Participants: Sixty-five AMD patients originally treated with ranibizumab in the phase 3 Anti-VEGF Antibody for the Treatment of Predominantly Classic Choroidal Neovascularization in AMD (ANCHOR) trial, Minimally Classic/Occult Trial of the Anti-VEGF Antibody Ranibizumab in the Treatment of Neovascular AMD (MARINA) trial, and Open-Label Extension Trial of Ranibizumab for Choroidal Neovascularization Secondary to Age-Related Macular Degeneration (HORIZON).Methods: Fourteen clinical trial sites recruited their original subjects for a return evaluation. Individual subject comparisons were obtained from the ANCHOR, MARINA, and HORIZON databases.Main Outcome Measures: The primary end point was percentage with best-corrected visual acuity (BCVA) of 20/70 or better; secondary outcomes included mean change in letter score compared with previous time points and anatomic results on fluorescein angiography, spectral-domain ocular coherence tomography (OCT), and fundus autofluorescence (FAF).Results: At a mean of 7.3 years (range, 6.3–8.5 years) after entry into ANCHOR or MARINA, 37% of study eyes met the primary end point of 20/70 or better BCVA, with 23% achieving a BCVA of 20/40 or better. Thirty-seven percent of study eyes had BCVA of 20/200 or worse. Forty-three percent of study eyes had a stable or improved letter score (≥0-letter gain) compared with ANCHOR or MARINA baseline measurements, whereas 34% declined by 15 letters or more, with overall a mean decline of 8.6 letters (P<0.005). Since exit from the HORIZON study, study eyes had received a mean of 6.8 anti-vascular endothelial growth factor (VEGF) injections during the mean 3.4-year interval; a subgroup of patients who received 11 or more anti-VEGF injections had a significantly better mean gain in letter score since HORIZON exit (P<0.05). Active exudative disease was detected by spectral-domain OCT in 68% of study eyes, and 46% were receiving ongoing ocular anti-VEGF treatments. Macular atrophy was detected by FAF in 98% of eyes, with a mean area of 9.4 mm2; the area of atrophy correlated significantly with poor visual outcome (P<0.0001).Conclusions: Approximately 7 years after ranibizumab therapy in the ANCHOR or MARINA trials, one third of patients demonstrated good visual outcomes, whereas another third had poor outcomes. Compared with baseline, almost half of eyes were stable, whereas one third declined by 15 letters or more. Even at this late stage in the therapeutic course, exudative AMD patients remain at risk for substantial visual decline.Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.
Editorial board/title page
Publication date: July 2013Source:Progress in Retinal and Eye Research, Volume 35
Corneal Hysteresis as a Risk Factor for Glaucoma Progression: A Prospective Longitudinal Study – Corrected Proof
Purpose: To evaluate the role of corneal hysteresis (CH) as a risk factor for the rate of visual field progression in a cohort of patients with glaucoma followed prospectively over time.Design: Prospective observational cohort study.Participants: The study group included 114 eyes of 68 patients with glaucoma followed for an average of 4.0±1.1 years. Visual fields were obtained with standard automated perimetry. Included eyes had a median number of 7 (range, 5–12) tests during follow-up.Methods: The CH measurements were acquired at baseline using the Ocular Response Analyzer (Reichert Instruments, Depew, NY). Evaluation of rates of visual field change during follow-up was performed using the visual field index (VFI). Linear mixed models were used to investigate the relationship between rates of visual field loss and baseline CH, baseline intraocular pressure (IOP), and central corneal thickness (CCT), while adjusting for potentially confounding factors. An interaction term between IOP and CH was included in the model to investigate whether the effect of IOP on rates of progression depended on the level of CH.Main Outcome Measures: Effects of CH, IOP, and CCT on rates of VFI loss over time.Results: The CH had a significant effect on rates of visual field progression over time. In the univariable model including only CH as a predictive factor along with time and their interaction, each 1 mmHg lower CH was associated with a 0.25%/year faster rate of VFI decline over time (P < 0.001). The multivariable model showed that the effect of IOP on rates of progression depended on CH. Eyes with high IOP and low CH were at increased risk for having fast rates of disease progression. The CH explained a larger proportion of the variation in slopes of VFI change than CCT (17.4% vs. 5.2%, respectively).Conclusions: The CH measurements were significantly associated with risk of glaucoma progression. Eyes with lower CH had faster rates of visual field loss than those with higher CH. The prospective longitudinal design of this study supports the role of CH as an important factor to be considered in the assessment of the risk of progression in patients with glaucoma.Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.