Outcomes of trabecular microbypass surgery: Comparison of resident trainees and attending surgeons

PURPOSE

To determine the efficacy, safety, and surgical outcomes of trabecular microbypass stent (iStent) surgery performed by resident trainees and attending surgeons.

SETTING

Wills Eye Hospital, Philadelphia, Pennsylvania, USA.

DESIGN

Retrospective case series.

METHODS

Records of all patients who had microbypass stent surgery by a resident at Wills Eye Hospital were retrospectively reviewed. The attending-performed group included any patient who had a microbypass stent implanted by an attending surgeon on the same day a resident case was performed.

RESULTS

Between 2016 and 2018, 31 microbypass stents were implanted by a resident supervised by an attending and 93 microbypass stents were implanted by an attending surgeon on the day a resident case was performed. The mean follow-up was 16.2 months ± 17.9 (SD). The mean intraocular pressure (IOP) decreased from 16.0 ± 4.6 mm Hg at baseline to 14.0 ± 3.1 mm Hg at most recent follow-up visit in the resident group (P = .02) and from 17.5 ± 4.8 mm Hg to 15.1 ± 4.3 mm Hg, respectively, in the attending group (P < .001). The final mean IOP and mean number of hypotensive medications were similar between the 2 groups (P = .83 and P = .12, respectively). Self-resolving hyphema occurred in 1 resident case and 2 attending cases. The resident group had 1 case of iridodialysis, which did not require additional surgery. One eye in the attending group ultimately required a trabeculectomy.

CONCLUSION

Microbypass stent implantation by resident trainees with attending supervision had similar efficacy and safety as surgery performed by attending surgeons.

Philadelphia Telemedicine Glaucoma Detection and Follow-Up Study: Cataract Classifications Following Eye Screening

Background: Cataracts are a major cause of visual impairment and blindness in the United States and worldwide. Introduction: Risk factors for cataracts include age over 40 years, smoking, diabetes, low socioeconomic status, female sex, steroid use, ocular trauma, genetic factors, and exposure to ultraviolet-B light. Community-based telemedicine vision screenings can be an efficient method for detecting cataracts in underserved populations. The Philadelphia Telemedicine Glaucoma Detection and Follow-Up Study reports the prevalence and risk factors for cataracts in individuals screened and examined for glaucoma and other eye diseases. Materials and Methods: A total of 906 high-risk individuals were screened for glaucoma using telemedicine in seven primary care practices and four Federally Qualified Health Centers in Philadelphia. Participants with suspicious nerves or other abnormalities on fundus photographs, unreadable images, and ocular hypertension returned for an eye examination with an ophthalmologist at the same community location. Results: Of the participants screened through telemedicine, 347 (38.3%) completed a follow-up eye examination by an ophthalmologist. Of these, 267 (76.9%) were diagnosed with cataracts, of which 38 (14.2%) had visually significant cataracts. Participants who were diagnosed with visually significant cataract were more likely to be older (p < 0.001), have diabetes (p = 0.003), and worse visual acuity (p < 0.001). Discussion: Our study successfully detected and confirmed cataracts in a targeted, underserved urban population at high risk for eye disease. Conclusions: Telemedicine programs offer an opportunity to identify and refer individuals who would benefit from continuous follow-up eye care and treatment to improve visual function and quality of life.

Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: Ocular Findings at Two Health Centers

Blindness from glaucoma can be prevented by early detection and treatment. Telemedicine improves access to treatment in high-risk populations that face barriers to receiving adequate ophthalmic care. We used a practice-based telemedicine screening model at two health centers. Telemedicine imaging of the fundus and optic nerve, followed by a complete eye exam at the same location for participants with abnormal findings, unreadable images, or ocular hypertension (OHTN), was performed. A total of 182 participants were screened, of whom 108 qualified for a complete eye exam. Of these, 62 (34.1%) had abnormal images, 12 (6.6%) had OHTN, and 34 (18.7%) had unreadable images. Eighty-nine of the 108 (82%) returned for the complete eye exam. Predominantly, participants were African American with glaucoma suspect and cataract. Screening location was an important factor for follow-up. Assessment of the fundus and optic disc using telemedicine resulted in early detection of glaucoma and other ocular pathology.

Awareness of ocular diagnosis, transportation means, and barriers to ophthalmology follow-up in the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study

Purpose: The purpose of this study was to assess factors affecting follow-up eye care in participants enrolled in the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study, such as awareness of ocular diagnosis, availability of transportation methods, and reasons for missing eye care appointments. Methods: The sample included 172 participants who were randomized to the intervention group and contacted by the social worker. Results: A total of 155 participants completed the assessment form, which was used as an instrument to assess factors affecting adherence to follow-up eye care. The main reasons for missing eye exam appointments were feeling ill (38.1%, n = 59) and forgetting the appointment (34.2%, n = 53). In addition, 45 (29.2%) participants were unaware of or did not comprehend the severity of their ocular diagnosis. Common methods of transportation included public transportation (31.6%, n = 49), driving (29.7%, n = 46), and being driven (27.7%, n = 43) to their appointment. Conclusion: These results suggest that individuals in need of eye care may benefit from additional assistance of a social worker regarding ongoing eye exam appointment reminders and in-depth explanation of their ocular diagnosis.

Validation and reproducibility of the Heidelberg Edge Perimeter in the detection of glaucomatous visual field defects

AIM

To validate the ability of the Heidelberg Edge Perimeter (HEP) in detecting glaucomatous visual field (VF) defects compared to the Octopus Visual Field (OVF) Analyzer and to determine the test-retest repeatability of both modalities.

METHODS

This prospective, cross-sectional study was conducted at Wills Eye Hospital, Philadelphia, PA. Glaucoma subjects and unaffected controls underwent VF testing using HEP standard automated perimetry (SAP) III 30-2 Adaptive Staircase Thresholding Algorithm (ASTA) FAST protocol and OVF G-TOP white-on-white strategy. Testing order was randomized. Pearson's correlation coefficient was calculated for both mean deviation (MD) and pattern standard deviation/square root of loss of variance (PSD/sLV). Receiver operating characteristic (ROC) curves were used to determine the diagnostic abilities of both modalities. Glaucoma subjects returned for repeat testing and intraclass correlation coefficients (ICCs) were calculated to assess test-retest repeatability.

RESULTS

Seventy-nine subjects with glaucoma and 36 unaffected controls were enrolled. HEP and OVF were significantly correlated for both MD (r=-0.84; P<0.01) and PSD/sLV (r=0.79; P<0.01). Areas under the ROC curves (AUCs) were also comparable between HEP and OVF for both MD (0.74 and 0.79, respectively; P=0.26) and PSD/sLV (0.74 and 0.82; P=0.08). ICC was high for both HEP (0.96 for MD, 0.95 for PSD/sLV) and OVF (0.82 and 0.88, respectively). Mean test duration (min) was significantly shorter for OVF (2.63) compared to HEP (5.15; P<0.01).

CONCLUSION

HEP and OVF show strong correlation for both MD and PSD/sLV, and have similar validity for detecting glaucoma. The test-retest repeatability is high for both HEP and OVF, however the average testing duration of HEP is significantly longer than that of OVF.

Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: confirmation between eye screening and comprehensive eye examination diagnoses

AIMS

To evaluate agreement between ocular findings of a telemedicine eye screening (visit 1) with diagnoses of a comprehensive eye examination (visit 2).

METHODS

A primary care practice (PCP)-based telemedicine screening programme incorporating fundus photography, intraocular pressure (IOP) and clinical information was conducted. Eligible individuals were African American, Hispanic/Latino or Asian over the age of 40; Caucasian individuals over age 65; and adults of any ethnicity over age 40 with a family history of glaucoma or diabetes. Participants with abnormal images or elevated IOP were invited back for a complete eye examination. Both visit 1 and visit 2 were conducted at participants' local PCP. Ocular findings at visit 1 and eye examination diagnoses at visit 2 are presented, including a cost analysis.

RESULTS

Of 906 participants who attended visit 1, 536 were invited to visit 2 due to ocular findings or unreadable images. Among the 347 (64.9%) who attended visit 2, 280 (80.7%) were diagnosed with at least one ocular condition. Participants were predominately women (59.9%) and African American (65.6%), with a mean age (±SD) of 60.6±11.0 years. A high diagnostic confirmation rate (86.0%) was found between visit 1 and visit 2 for any ocular finding. Of 183 with suspicious nerves at visit 1, 143 (78.1%) were diagnosed as glaucoma or glaucoma suspects at visit 2.

CONCLUSIONS

This screening model may be adapted and scaled nationally and internationally. Referral to an ophthalmologist is warranted if abnormal or unreadable fundus images are detected or IOP is >21 mm Hg.

TRIAL REGISTRATION NUMBER

NCT02390245.

Is primary open-angle glaucoma an ocular manifestation of systemic disease?

Primary open-angle glaucoma is currently characterized by a pattern of progressive retinal ganglion cell loss that stems from a complex underlying pathophysiology that remains poorly elucidated. The roles of blood flow and intraocular pressure (IOP) in glaucoma pathogenesis have been extensively studied. Further, it has been established that lowering IOP can slow the progression of glaucoma. In addition, a number of influential factors have emerged and gained momentum over the years. Increasing evidence implicates the contributions of low cerebrospinal fluid pressure, autoimmunity, neurodegeneration, and impaired autoregulation towards glaucoma pathophysiology. We aggregate and explore these different camps of thought that have garnered attention over the last few decades, and, in doing so, aim to challenge the long-standing view of glaucoma as a primary disease of the eye. A shift in our perspective towards understanding glaucoma as an ocular manifestation of systemic dysregulation may lead ultimately to better clinical management of the disease.

Prospective Evaluation of Two iStent® Trabecular Stents, One iStent Supra® Suprachoroidal Stent, and Postoperative Prostaglandin in Refractory Glaucoma: 4-year Outcomes

Introduction

This study evaluates long-term outcomes of two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin in eyes with refractory open angle glaucoma (OAG).

Methods

Prospective ongoing 5-year study of 80 eligible subjects (70 with 4-year follow-up) with OAG and IOP ≥ 18 mmHg after prior trabeculectomy and while taking 1–3 glaucoma medications. Subjects received two iStent^® trabecular micro-bypass stents, one iStent Supra^® suprachoroidal stent, and postoperative travoprost. Postoperative IOP was measured with medication and annually following medication washouts. Performance was measured by the proportion of eyes with ≥ 20% IOP reduction on one medication (the protocol-specified prostaglandin) versus preoperative medicated IOP (primary outcome); and the proportion of eyes with postoperative IOP ≤ 15 and ≤ 18 mmHg on one medication (secondary outcome). Additional clinical and safety data included medications, visual field, pachymetry, gonioscopy, adverse events, visual acuity, and slit-lamp and fundus examinations.

Results

Preoperatively, mean medicated IOP was 22.0 ± 3.1 mmHg on 1.2 ± 0.4 medications, and mean unmedicated IOP was 26.4 ± 2.4 mmHg. Postoperatively, among eyes without later cataract surgery, mean medicated IOP at all visits through 48 months was ≤ 13.7 mmHg (≥ 37% reduction), and annual unmedicated IOP was ≤ 18.4 mmHg (reductions of ≥ 30% vs. preoperative unmedicated IOP and ≥ 16% vs. preoperative medicated IOP). At all postoperative visits among eyes without additional surgery or medication, ≥ 91% of eyes had ≥ 20% IOP reduction on one medication versus preoperative medicated IOP. At month 48, 97 and 98% of eyes achieved IOP ≤ 15 and ≤ 18 mmHg, respectively, on one medication. Six eyes required additional medication, no eyes required additional glaucoma surgery, and safety measurements were favorable throughout follow-up.

Conclusion

IOP control was achieved safely with two trabecular micro-bypass stents, one suprachoroidal stent, and postoperative prostaglandin. This microinvasive, ab interno approach introduces a possible new treatment option for refractory disease.

Trial Registration

NCT01456390.

Funding

Glaukos Corporation.

Electronic supplementary material

The online version of this article (10.1007/s12325-018-0666-4) contains supplementary material, which is available to authorized users.

Two Phase 3 Clinical Trials Comparing the Safety and Efficacy of Netarsudil to Timolol in Patients With Elevated Intraocular Pressure: Rho Kinase Elevated IOP Treatment Trial 1 and 2 (ROCKET-1 and ROCKET-2)

PURPOSE

To evaluate the efficacy and ocular and systemic safety of netarsudil 0.02% ophthalmic solution, a rho-kinase inhibitor and norepinephrine transporter inhibitor, in patients with open-angle glaucoma and ocular hypertension.

DESIGN

Double-masked, randomized noninferiority clinical trials: Rho Kinase Elevated IOP Treatment Trial 1 and 2 (ROCKET-1 and ROCKET-2).

METHODS

After a washout of all pre-study ocular hypotensive medications, eligible patients were randomized to receive netarsudil 0.02% once daily (q.d.), timolol 0.5% twice a day (b.i.d.), and (ROCKET-2 only) netarsudil 0.02% b.i.d. Data through 3 months from both studies are provided in this report.

RESULTS

Enrolled into the 2 studies were 1167 patients. Treatment with netarsudil q.d. produced clinically and statistically significant reductions from baseline intraocular pressure (P < .001), and was noninferior to timolol in the per-protocol population with maximum baseline IOP < 25 mm Hg in both studies (ROCKET-2, primary outcome measure and population, ROCKET-1, post hoc outcome measure). Netarsudil b.i.d. was also noninferior to timolol (ROCKET-2). The most frequent adverse event was conjunctival hyperemia, the incidence of which ranged from 50% (126/251, ROCKET-2) to 53% (108/203, ROCKET-1) for netarsudil q.d., 59% (149/253, ROCKET-2) for netarsudil b.i.d., and 8% (17/208, ROCKET-1) to 11% (27/251, ROCKET-2) for timolol (P < .0001 for netarsudil vs timolol).

CONCLUSIONS

In 2 large, randomized, double-masked trials reported here, once-daily dosing of netarsudil 0.02% was found to be effective and well tolerated for the treatment of patients with ocular hypertension and open-angle glaucoma. The novel pharmacology and aqueous humor dynamic effects of this molecule suggest it may be a useful addition to the armamentarium of ocular hypotensive medications.

Long-term titrated IOP control with one, two, or three trabecular micro-bypass stents in open-angle glaucoma subjects on topical hypotensive medication: 42-month outcomes

Purpose

Evaluate long-term outcomes after one, two, or three trabecular micro-bypass stents implanted in a standalone procedure in eyes with open-angle glaucoma taking ocular hypotensive medication.

Patients and methods

Prospective randomized ongoing study of 119 subjects (109 with 42-month follow-up) with open-angle glaucoma, preoperative intraocular pressure (IOP) 18-30 mmHg on one to three glaucoma medications, and unmedicated (post-washout) IOP 22-38 mmHg. Subjects were randomized to receive one (n=38), two (n=41), or three (n=40) iStent trabecular micro-bypass stents in a standalone procedure. Postoperatively, IOP was measured with medication and annually following washout. Data included IOP, medications, gonioscopy, pachymetry, visual field, visual acuity, adverse events, and slit-lamp and fundus examinations.

Results

Preoperative mean medicated IOP was 19.8±1.3 mmHg on 1.71 medications in one-stent eyes, 20.1±1.6 mmHg on 1.76 medications in two-stent eyes, and 20.4±1.8 mmHg on 1.53 medications in three-stent eyes. Post-washout IOP prior to stent implantation was 25.0±1.2, 25.0±1.7, and 25.1±1.9 mmHg in the three groups, respectively. Postoperatively, Month 42 medicated IOP was 15.0±2.8, 15.7±1.0 and 14.8±1.3 mmHg in the three groups, and post-washout IOP (Months 36-37) was 17.4±0.9, 15.8±1.1 and 14.2±1.5 mmHg, respectively. IOP reduction ≥20% without medication was achieved in 89%, 90%, and 92% of one-, two-, and three-stent eyes, respectively, at Month 12; and in 61%, 91%, and 91% of eyes, respectively, at Month 42. The need for additional medication remained consistent at Months 12 and 42 in multi-stent eyes (four two-stent eyes and three three-stent eyes at both time points), whereas it increased in single-stent eyes (four eyes at Month 12 versus 18 eyes at Month 42). Safety parameters were favorable in all groups.

Conclusion

The standalone implantation of either single or multiple iStent^® device(s) produced safe, clinically meaningful IOP and medication reductions through 42 months postoperatively, with incrementally greater and more sustained reductions in multi-stent eyes.

Visual Field Changes in Professional Wind versus Non-wind Musical Instrument Players in the Philadelphia Orchestra

Purpose:

We compare the prevalence of glaucoma in professional wind versus non-wind instrument players in the Philadelphia Orchestra. Visual field changes in individuals with glaucoma and glaucoma suspects were evaluated, and the results were correlated with cumulative practice time.

Methods:

In this cross-sectional, observational study, fifty-one Philadelphia Orchestra musicians were enrolled and categorized as wind or non-wind instrument players. All study participants underwent screening fundus photography. Participants with optic discs suspicious for glaucoma underwent further evaluation, including standard automated visual field perimetry and a comprehensive eye examination by a glaucoma specialist.

Results:

Of the 51 musicians enrolled, 9 of the 21 wind instrument players (43%) and 8 of the 30 non-wind instrument players (27%) were suspected of developing glaucoma in at least one eye (P = 0.25), with examinations performed on 12 of the 17 returning musicians (71%) for further confirmation. Wind instrument players exhibited significantly higher Octopus visual field mean defect scores (1.08 ± 1.5 dB) than non-wind instrument players (−0.43 ± 0.7 dB; P < 0.001). There was a significant association between cumulative hours playing wind instruments and visual field mean defect (P < 0.001).

Conclusion:

Among members of the Philadelphia Orchestra, the difference in prevalence of glaucoma suspicious optic discs between wind and non-wind instrument players was not significant. The clinical significance of the greater visual field mean defect found in wind instrument players, and the association between the degree of visual field mean defect and the cumulative practice-time of playing wind instruments, needs further investigation.

Applying RE-AIM to evaluate two community-based programs designed to improve access to eye care for those at high-risk for glaucoma

INTRODUCTION

Glaucoma is a leading cause of vision loss and blindness in the U.S. Risk factors include African American race, older age, family history of glaucoma, and diabetes. This paper describes the evaluation of a mobile eye health and a telemedicine program designed to improve access to eye care among people at high-risk for glaucoma.

METHODS

The RE-AIM (reach, efficacy, adoption, implementation, and maintenance) evaluation framework was used to harmonize indicators. Both programs provided community-based eye health education and eye services related to glaucoma detection and care. Each program reported data on participants and community partners. An external evaluator conducted site visit interviews with program staff and community partners. Quantitative and qualitative data were integrated and analyzed using the RE-AIM dimensions.

DISCUSSION

By targeting high-risk populations and providing comprehensive eye exams, both programs detected a large proportion of new glaucoma-related cases (17-19%) - a much larger proportion than that found in the general population (<2%). The educational intervention increased glaucoma knowledge; evidence that it led people to seek eye care was inconclusive.

CONCLUSIONS

Evaluation findings from the mobile eye health program and the telemedicine program may provide useful information for wider implementation in public health clinics and in optometrist clinics located in retail outlets.

Evaluation of Nonmydriatic Hand-held Optic Disc Photography Grading in the Philadelphia Glaucoma Detection and Treatment Project

PURPOSE

To determine the reproducibility of optic disc photograph grading obtained by a hand-held fundus camera and to determine the diagnostic value of these photographs in detecting patients with glaucoma in a community-based glaucoma-detection program.

MATERIALS AND METHODS

Patients underwent slit-lamp examination by an ophthalmologist who graded each patient's optic discs using 2 methods: cup-to-disc ratio (CDR) and disc damage likelihood scale (DDLS). After a comprehensive glaucoma evaluation, patients were diagnosed as having "glaucoma," "glaucoma suspect," or "no glaucoma." Nonmydriatic, monoscopic optic disc photographs were then taken with a portable digital imaging device. On a different day, the same examiner and a second observer graded the disc photographs in a masked manner and determined a diagnostic impression based only on the disc photographs.

RESULTS

Of the 1649 patients examined, 119 subjects were randomly selected according to 3 groups of diagnoses: "glaucoma" (n=36), "glaucoma suspect" (n=50), and "no glaucoma" (n=33). For CDR, the intraobserver agreement was 0.71 and the interobserver agreement was 0.69. For disc DDLS, the intraobserver agreement was 0.65 and the interobserver agreement was 0.67. The area under the receiver-operating characteristic distinguishing between normal and glaucoma was 0.88 and 0.86 for CDR and disc DDLS, respectively.

CONCLUSIONS

Nonmydriatic, monoscopic disc photographs obtained by a hand-held camera had only moderate disc grading reproducibility. This could be due to a reduced quality of images, making interpretation more challenging, due to taking photographs through small pupils by a hand-held camera and the high percentage of patients with significant cataracts.

Mutations of conserved non-coding elements of PITX2 in patients with ocular dysgenesis and developmental glaucoma

Mutations in FOXC1 and PITX2 constitute the most common causes of ocular anterior segment dysgenesis (ASD), and confer a high risk for secondary glaucoma. The genetic causes underlying ASD in approximately half of patients remain unknown, despite many of them being screened by whole exome sequencing. Here, we performed whole genome sequencing on DNA from two affected individuals from a family with dominantly inherited ASD and glaucoma to identify a 748-kb deletion in a gene desert that contains conserved putative PITX2 regulatory elements. We used CRISPR/Cas9 to delete the orthologous region in zebrafish in order to test the pathogenicity of this structural variant. Deletion in zebrafish reduced pitx2 expression during development and resulted in shallow anterior chambers. We screened additional patients for copy number variation of the putative regulatory elements and found an overlapping deletion in a second family and in a potentially-ancestrally-related index patient with ASD and glaucoma. These data suggest that mutations affecting conserved non-coding elements of PITX2 may constitute an important class of mutations in patients with ASD for whom the molecular cause of their disease have not yet been identified. Improved functional annotation of the human genome and transition to sequencing of patient genomes instead of exomes will be required before the magnitude of this class of mutations is fully understood.

Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: Methods and Screening Results

PURPOSE

To describe methodology and screening results from the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study.

DESIGN

Screening program results for a prospective randomized clinical trial.

METHODS

Individuals were recruited who were African-American, Hispanic/Latino, or Asian over age 40 years; white individuals over age 65 years; and any ethnicity over age 40 years with a family history of glaucoma or diabetes. Primary care offices and Federally Qualified Health Centers were used for telemedicine (Visit 1). Two posterior fundus photographs and 1 anterior segment photograph were captured per eye in each participant, using a nonmydriatic, autofocus, hand-held fundus camera (Volk Optical, Mentor, Ohio, USA). Medical and ocular history, family history of glaucoma, visual acuity, and intraocular pressure measurements using the ICare rebound tonometer (ICare, Helsinki, Finland) were obtained. Images were read remotely by a trained retina reader and a glaucoma specialist.

RESULTS

From April 1, 2015, to February 6, 2017, 906 individuals consented and attended Visit 1. Of these, 553 participants were female (61.0%) and 550 were African-American (60.7%), with a mean age of 58.7 years. A total of 532 (58.7%) participants had diabetes, and 616 (68%) had a history of hypertension. During Visit 1, 356 (39.3%) participants were graded with a normal image. Using image data from the worse eye, 333 (36.8%) were abnormal and 155 (17.1%) were unreadable. A total of 258 (28.5%) had a suspicious nerve, 62 (6.8%) had ocular hypertension, 102 (11.3%) had diabetic retinopathy, and 68 (7.5%) had other retinal abnormalities.

CONCLUSION

An integrated telemedicine screening intervention in primary care offices and Federally Qualified Health Centers detected high rate of suspicious optic nerves, ocular hypertension, and retinal pathology.

Comparing glaucomatous disc change using stereo disc viewing and the MatchedFlicker programme in glaucoma experts and trainees

BACKGROUND/AIMS

The objective of this study is to evaluate the accuracy and speed of trainees and experienced glaucoma specialists using the MatchedFlicker software against the manual examination of stereoscopic disc photographs for detecting glaucomatous optic disc change.

METHODS

Three experienced glaucoma specialists, two resident ophthalmologists and one glaucoma fellow from multiple institutions independently evaluated the same 140 image pairs from 100 glaucomatous/ocular hypertensive eyes using a handheld stereo viewer and the MatchedFlicker programme. Fifty had progression to glaucoma as determined by the Ocular Hypertension Treatment Study (OHTS) Optic Disc Reading Group and endpoint committee, and 50 more were negative controls for progression with photos taken a few minutes apart. Twenty photo pairs from each of the two groups were duplicated for reviewer variability analysis. The initial viewing method was randomised and then alternated for each group of 70 image pairs. Reviewer accuracy and evaluation time for each method were measured.

RESULTS

Evaluators averaged 8.6 s faster per image pair (26%) with the MatchedFlicker programme than with the stereo viewer (p=0.0007). Evaluators correctly identified more image pairs when using the MatchedFlicker software over the stereo viewer (p=0.0003). There was no significant difference between the expert and trainee group in speed or overall accuracy for either method. Experts were significantly more consistent than trainees with the duplicate image pairs (p=0.029). Trainees appeared more reluctant to designate eyes as showing glaucoma progression than experts.

CONCLUSIONS

Both expert glaucoma specialists and ophthalmologists in various stages of training had greater accuracy and speed with the MatchedFlicker programme than with a handheld stereoscopic viewer.

Cost-comparison of two trabecular micro-bypass stents versus selective laser trabeculoplasty or medications only for intraocular pressure control for patients with open-angle glaucoma

AIM

Patients with open-angle glaucoma (OAG) whose intraocular pressure is not adequately controlled by one medication have several treatment options in the US. This analysis evaluated direct costs of unilateral eye treatment with two trabecular micro-bypass stents (two iStents) compared to selective laser trabeculoplasty (SLT) or medications only.

MATERIALS AND METHODS

A population-based, annual state-transition, probabilistic, cost-of-care model was used to assess OAG-related costs over 5 years. Patients were modeled to initiate treatment in year zero with two iStents, SLT, or medications only. In years 1-5, patients could remain on initial treatment or move to another treatment option(s), or filtration surgery. Treatment strategy change probabilities were identified by a clinician panel. Direct costs were included for drugs, procedures, and complications.

RESULTS

The projected average cumulative cost at 5 years was lower in the two-stent treatment arm ($4,420) compared to the SLT arm ($4,730) or medications-only arm ($6,217). Initial year-zero costs were higher with two iStents ($2,810) than with SLT ($842) or medications only ($996). Average marginal annual costs in years 1-5 were $322 for two iStents, $777 for SLT, and $1,044 for medications only. The cumulative cost differences between two iStents vs SLT or medications only decreased over time, with breakeven by 5 or 3 years post-initiation, respectively. By year 5, cumulative savings with two iStents over SLT or medications only was $309 or $1,797, respectively.

LIMITATIONS

This analysis relies on clinical expert panel opinion and would benefit from real-world evidence on use of multiple procedures and treatment switching after two-stent treatment, SLT, or polypharmaceutical initial approaches.

CONCLUSIONS

Despite higher costs in year zero, annual costs thereafter were lowest in the two-stent treatment arm. Two-stent treatment may reduce OAG-related health resource use, leading to direct savings, especially over medications only or at longer time horizons.

Costs of a community-based glaucoma detection programme: analysis of the Philadelphia Glaucoma Detection and Treatment Project

Background

Glaucoma is the foremost cause of irreversible blindness, and more than 50% of cases remain undiagnosed. Our objective was to report the costs of a glaucoma detection programme operationalised through Philadelphia community centres.

Methods

The analysis was performed using a healthcare system perspective in 2013 US dollars. Costs of examination and educational workshops were captured. Measures were total programme costs, cost/case of glaucoma detected and cost/case of any ocular disease detected (including glaucoma). Diagnoses are reported at the individual level (therefore representing a diagnosis made in one or both eyes). Staff time was captured during site visits to 15 of 43 sites and included time to deliver examinations and workshops, supervision, training and travel. Staff time was converted to costs by applying wage and fringe benefit costs from the US Bureau of Labor Statistics. Non-staff costs (equipment and mileage) were collected using study logs. Participants with previously diagnosed glaucoma were excluded.

Results

1649 participants were examined. Mean total per-participant examination time was 56 min (SD 4). Mean total examination cost/participant was $139. The cost/case of glaucoma newly identified (open-angle glaucoma, angle-closure glaucoma, glaucoma suspect, or primary angle closure) was $420 and cost/case for any ocular disease identified was $273.

Conclusion

Glaucoma examinations delivered through this programme provided significant health benefit to hard-to-reach communities. On a per-person basis, examinations were fairly low cost, though opportunities exist to improve efficiency. Findings serve as an important benchmark for planning future community-based glaucoma examination programmes.