OCT Segmentation Errors with Bruch's Membrane Opening-Minimum Rim Width as Compared with Retinal Nerve Fiber Layer Thickness.

OBJECTIVE: To compare the magnitude and location of automated segmentation errors of the Bruch's membrane opening-minimum rim width (BMO-MRW) and retinal nerve fiber layer thickness (RNFLT). DESIGN: Cross-sectional study. PARTICIPANTS: We included 162 glaucoma suspect or open-angle glaucoma eyes from 162 participants. METHODS: We used spectral-domain optic coherence tomography (Spectralis 870 nm, Heidelberg Engineering) to image the optic nerve with 24 radial optic nerve head B-scans and a 12-degree peripapillary circle scan, and exported the native "automated segmentation only" results for BMO-MRW and RNFLT. We also exported the results after "manual refinement" of the measurements. MAIN OUTCOME MEASURES: We calculated the absolute and proportional error globally and within the 12 30-degree sectors of the optic disc. We determined whether the glaucoma classifications were different between BMO-MRW and RNFLT as a result of manual and automatic segmentation. RESULTS: The absolute error mean was larger for BMO-MRW than for RNFLT (10.8 µm vs. 3.58 µm, P < 0.001). However, the proportional errors were similar (4.3% vs. 4.4%, P = 0.47). In a multivariable regression model, errors in BMO-MRW were not significantly associated with age, location, magnitude, or severity of glaucoma loss (all P ≥ 0.05). However, larger RNFLT errors were associated with the superior and inferior sector location, thicker nerve fiber layer, and worse visual field (all P < 0.05). Errors in BMO-MRW and RNFLT were not likely to occur in the same sector location (R2 = 0.001; P = 0.15). With manual refinement, the glaucoma classification changed in 7.8% and 6.2% of eyes with BMO-MRW and RNFLT, respectively. CONCLUSIONS: Both BMO-MRW and RNFLT measurements included segmentation errors, which did not seem to have a common location, and may result in differences in glaucoma classification. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Patients with Low Vision Struggle with Placing Eye Drops and Benefit from an Eye Drop Aid.

PURPOSE: To evaluate eye drop self-administration in a low-vision patient population and test whether a nose-pivoted drop delivery device (NPDD, GentleDrop) can improve eye drop delivery in these patients. DESIGN: Repeated-measures case series. PARTICIPANTS: Thirty subjects (58 eyes) with low vision, defined as best-corrected visual acuity worse than 20/60 or visual field worse than 20° in the better-seeing eye. METHODS: We video-recorded subjects while self-administering eye drops using their own traditional delivery at baseline, after a standardized teaching, and with an NPDD. Two masked graders independently reviewed each drop delivery. Primary success was defined as the drop reaching the eye without the bottle touching the eye or eyelids. Subjects rated ease-of-use (1-10 scale, 10 = easiest) after each drop delivery and completed a satisfaction survey, which included asking whether subjects could place drops independently (1-5 scale, 5 = most independent). MAIN OUTCOME MEASURES: Logistic-transformed generalized estimating equation regression to compare technique satisfaction, ease-of-use, independence, no contact, and success. RESULTS: Primary success was observed in 30 (52%) of 58 eyes at baseline and increased to 44 eyes (76%) with an NPDD (P = 0.013). Bottle tip contact occurred in 23 (40%) of 58 eyes at baseline and 8 eyes (14%) with an NPDD (P = 0.004). Mean ease-of-use scores were 6.7 ± 3.1 at baseline and 8.3 ± 1.8 (P < 0.001) with an NPDD. Likewise, the NPDD improved success, bottle tip contact, and ease-of-use compared with post-teaching traditional delivery (P < 0.01). Twenty-two (73%) of 30 subjects preferred the NPDD to traditional delivery. Twenty-nine (97%) thought the NPDD was comfortable to use, and all would recommend the device. A subgroup analysis was performed on 16 subjects that self-reported difficulty instilling drops at baseline. The NPDD showed similar results, and it increased confidence in placing drops independently (4.6 ± 0.9) compared with baseline (2.7 ± 1.6, P < 0.001). Fifteen (94%) subjects in this subgroup preferred the NPDD. CONCLUSIONS: Low-vision subjects struggled to self-administer eye drops. An NPDD can improve bottle tip contact, ease-of-use, satisfaction, and independence. Eye care providers could consider screening low-vision patients about difficulty with eye drop self-administration and recommending eye drop aids. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Eye Drop Adherence With an Eye Drop Bottle Cap Monitor.

PRCIS: An eye drop bottle cap monitor with audio and visual alarms measured eye drop adherence in 50 subjects with glaucoma. Baseline adherence rates were too high to test if the alarms could improve adherence. PURPOSE: To determine if an eye drop bottle cap monitor can measure and improve adherence. MATERIALS AND METHODS: The Devers Drop Device (D3, Universal Adherence LLC) was designed to measure eye drop adherence by detecting bottle cap removal and replacement, and it can provide text, visual and audio alerts when a medication is due. In Stage 1, we determined baseline adherence for 50 subjects using a nightly eye drop over a 25-day period. Subjects with less than 90% baseline adherence were eligible for Stage 2. In Stage 2, we randomized subjects to receive either no reminder or automated D3 alerts for their nightly eye drop over a subsequent 25-day period. We defined adherence as the proportion of drops administered within 3 hours of the subjects' scheduled dosing time. Subjects completed 3 questions regarding satisfaction with the device and willingness to pay. RESULTS: The D3 monitor remained attached to the eye drop bottle cap for the duration of the study and collected adherence data in all 50 patients. In Stage 1, the mean adherence rate was 90 ± 18% (range 32-100%). Forty (80%) subjects had an adherence rate greater than 90%. Adherence rates were too high in Stage 1 to adequately test the effects of reminders in Stage 2. Ninety-eight percent (49/50) and 96% (48/50) of subjects agreed "the device always stayed attached to the bottle cap" and "I was able to use the device to take the drops", respectively. Patients would pay $61±83 (range $0-400) for a similar device to improve adherence. CONCLUSIONS: The D3 can measure eye drop adherence. Research subjects reported high satisfaction and willingness to pay for an eye drop bottle cap monitor. Glaucoma patients have high adherence when they are being monitored, and future studies with research subjects screened for poor adherence may further determine the benefit of electronic monitoring of adherence with and without electronic reminders.

Geospatial analysis of blindness within rural and urban counties.

PURPOSE: To determine the associations of blindness within rural and urban counties using a registry of blind persons and geospatial analytics. METHODS: We used the Oregon Commission for the Blind registry to determine the number of persons who are legally blind, as well as licensure data to determine the density of eye care providers (optometrists and ophthalmologists) within each county of the State of Oregon. We used geospatial statistics, analysis of variance, and logistic regression to determine the explanatory variables associated with blindness within counties. RESULTS: We included 8350 individuals who are legally blind within the state of Oregon in the calendar year 2015. The mean observed prevalence of registered blindness was 0.21% and ranged almost 9-fold from 0.04% to 0.58% among counties (p < .001). In univariate models, higher blindness was associated with increasing median age (p = .027), minority race (p < .001), decreased median household income (p < .001), increased poverty within a county (p < .001), and higher density of ophthalmologists (p = .003). Density of optometrists was not associated with prevalence of blindness (p = .89). The final multivariable model showed higher blindness to be associated with lower median household income, higher proportion of black race, and lower proportion of Hispanic race (p < .001 for all). CONCLUSION: Geospatial analytics identified counties with higher and lower than expected proportions of blindness even when adjusted for sociodemographic factors. Clinicians and researchers may use the methods and results of this study to better understand the distribution of individuals with blindness and the associated factors to help design public health interventions.

Intraocular Pressure and Medication Burden With Cataract Surgery Alone, or Cataract Surgery Combined With Trabecular Bypass or Goniotomy.

PRCIS: When compared with cataract surgery in glaucoma patients, trabecular micro-bypass and goniotomy resulted in a large decrease in the incidence of intraocular pressure (IOP) spikes, a modest effect on IOP, and a minimal effect on medication burden. PURPOSE: To compare changes in IOP and ocular hypotensive medications in 3 surgical cohorts: cataract surgery, cataract surgery with trabecular micro-bypass (cataract/trabecular), and cataract surgery with goniotomy (cataract/goniotomy). MATERIALS AND METHODS: We included 138 eyes diagnosed with open-angle glaucoma: (1) 84 eyes with cataract surgery alone, (2) 25 eyes with cataract/trabecular surgery, and (3) 29 eyes with cataract/goniotomy surgery. We compared the groups for postoperative IOP and the number of ocular hypotensive medications. We adjusted for preoperative IOP, and preoperative and postoperative number of ocular hypotensive medications. We defined an IOP spike as IOP ≥21 mm Hg and 10 mm Hg higher than preoperative on postoperative day 1. RESULTS: All 3 surgeries showed a decrease in IOP (P≤0.004) and medication burden (P≤0.001) at 3 and 6 months postoperatively when compared with their own preoperative baselines. When compared with cataract surgery alone, cataract/trabecular and cataract/goniotomy had similar IOP lowering at 1 month postoperatively, and variable results at 3 and 6 months. The change in ocular hypotensive medications was not statistically different between the surgical groups at any postoperative visit. Cataract/trabecular and cataract/goniotomy decreased IOP on postoperative day 1, and had relative risk reduction of ~70% for IOP spikes (P≤0.001 for both). CONCLUSION: Trabecular micro-bypass and goniotomy when added to cataract surgery resulted in a large decrease in IOP spikes, a modest effect on IOP, and a minimal effect on medication burden when compared with cataract surgery alone in glaucoma patients.

MicroPulse® Transscleral Laser Therapy - Fluence May Explain Variability in Clinical Outcomes: A Literature Review and Analysis.

Since the first peer-reviewed publication on MicroPulse® Transscleral Laser Therapy (MP-TLT) in 2010, authors worldwide have used a wide range of treatment parameter combinations with varying clinical efficacy in terms of the magnitude of intraocular pressure reduction, success rate, durability, and safety profile. This has made it difficult to determine the proper parameters necessary to optimize efficacy and safety, and has made comparison of results from one investigation to another difficult. The first goal of this paper is to explain and highlight the impact of the choices of exposure time and the number of sweeps per hemisphere in terms of "sweep velocity" on energy delivery to the eye. These treatment parameters are underreported in the literature. The second goal is to introduce fluence as a "dose" metric, that combines all the treatment parameters and constants into a single number. Fluence may be a better light-dose metric and a more reliable indicator of clinical outcomes compared to total energy.

Novel Eye Drop Delivery Aid Improves Outcomes and Satisfaction.

PURPOSE: To compare a nose-pivoted drop delivery device (NPDD) with traditional eye drop delivery in glaucoma subjects. DESIGN: Repeated-measures case series. PARTICIPANTS: Fifty glaucoma subjects (100 eyes) who reported difficulty self-administering eye drops. METHODS: We compared eye drop delivery using a NPDD against traditional delivery techniques at baseline (baseline traditional) and after standardized teaching (post-teaching traditional). Subjects used a 1-to-10 scale (10 being easiest) to rate the ease of delivery with each technique and completed a satisfaction survey. Two graders used digital video to independently review eye drop delivery and recorded: (1) accurate placement: the eye drop reached the ocular surface; (2) no contact: no bottle tip contact against the ocular or periocular surface; and (3)number of eye drops dispensed. We defined primary success as accurate placement and no contact; secondary success as primary success with only 1 drop dispensed. MAIN OUTCOME MEASURES: We used logistic-transformed generalized estimating equation (GEE) regression to compare technique satisfaction, accuracy, no contact, and primary and secondary success. Number of drops dispensed was compared using a Cox model. RESULTS: Forty-seven of 50 subjects (94%) preferred the NPDD over traditional eye drop delivery. The mean score for ease of use was higher for the NPDD (8.9 ± 1.1) than baseline traditional (6.7 ± 2.1; P < 0.001) and post-teaching traditional (7.0 ± 2.0; P < 0.001). Forty-nine of 50 (98%) subjects thought the NPDD was comfortable to use and would recommend the device. The eye drop reached the ocular surface in a similar percentage of subjects (>90%) with each method. The bottle tip contacted fewer eyes with the NPDD (10 eyes) than baseline traditional (33 eyes; P < 0.001) and post-teaching traditional (25 eyes; P = 0.009). The number of drops dispensed was lower with the NPDD (1.7 ± 1.2) than baseline traditional (2.2 ± 1.6; P = 0.017) and post-teaching traditional (2.4 ± 1.8; P = 0.006). The NPDD increased primary and secondary success of eye drop delivery (86% and 54%, respectively) compared to baseline traditional (66% [P = 0.001] and 28% [P < 0.001]) and post-teaching traditional (70% [P = 0.005] and 40% [P = 0.018]). CONCLUSIONS: Eye drop users preferred the NPDD over traditional eye drop delivery. The NPDD improved eye drop delivery success, reduced bottle tip contact, and decreased the number of eye drops wasted.

Predicting Adherence With the Glaucoma Treatment Compliance Assessment Tool.

PRéCIS:: Univariate and multivariable models using the Glaucoma Treatment Compliance Assessment Tool (GTCAT) statements identified multiple, patient-specific factors associated with adherence that could be used to inform personalized interventions to optimize glaucoma adherence. PURPOSE: The purpose of this study was to determine the health behavior factors related to glaucoma adherence in patients with self-reported poor adherence. METHODS: A research coordinator used the Chang Adherence Measure and the Morisky Medication Adherence Scale to identify subjects with poor self-reported glaucoma medication adherence and enrolled them in a 3-month study to electronically monitor medication adherence. At enrollment, the coordinator administered the GTCAT. We calculated the percentage of prescribed doses taken over a 3-month period using an electronic dose monitor (AdhereTech). We used Rasch analysis, and univariate and multivariable regression to determine the GTCAT statements that predicted electronically monitored adherence. RESULTS: The mean adherence was 73.8% (SD=21.04%, range: 13% to 100%). Rasch analysis showed that the GTCAT had a good overall fit and no differential bias (Anderson likelihood ratio test >0.05). Multiple GTCAT statements were associated with adherence, which represented increased knowledge, increased cues-to-action, decreased barriers, less depression, and increased self-efficacy (P<0.09 for each). The full GTCAT or a subset of statements had a high association with adherence (R range: 0.44 to 0.51, P<0.005 for all). The GTCAT identified >50% of patients who wanted more education about glaucoma; >68% who did not use reminders; and >40% who reported having difficulty using the eye drops. CONCLUSIONS: The GTCAT identified multiple factors associated with adherence. Clinicians and researchers could use this tool to identify specific barriers to adherence and develop potential interventions to improve adherence.

Effect of Trabeculectomy on OCT Measurements of the Optic Nerve Head Neuroretinal Rim Tissue.

Purpose: Ophthalmologists commonly perform glaucoma surgery to treat progressive glaucoma. Few studies have examined the stability of OCT neuroretinal rim parameters after glaucoma surgery for ongoing detection of glaucoma progression. Design: Longitudinal cohort study. Participants: 20 eyes (16 subjects) with primary open angle glaucoma who had undergone a trabeculectomy. Methods: We calculated the change in OCT parameters (minimum rim area (MRA), minimum rim width (MRW), Bruch's membrane opening (BMO) area, mean cup depth (MCD), anterior lamina cribrosa surface depth (ALCSD), prelaminar tissue thickness (PLTT), retinal nerve fiber layer thickness (RFNLT) during an interval from the visit before the surgery to the visit after the surgery, a span of approximately 6-months. We also calculated changes in the same eyes over two separate 6-month intervals that did not contain trabeculectomy to serve as control. We compared these intervals using a generalized linear model (with compound symmetry correlation structure), accounting for the correlation between time intervals for the same eye. Main outcomes measures: MRW, MRA, angle above the reference plane for MRW and MRA, BMO area, MCD, mean ALCSD, PLTT, RNFLT and visual field parameters (mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI)). Results: The intervals containing trabeculectomy showed a significant decrease in intraocular pressure (-9.2 mmHg, p<.001) when compared to control intervals. Likewise, the following neuroretinal rim parameters showed significant changes with trabeculectomy: increased MRW (+6.04µm, p=.001), increased MRA (+0.014mm2, p=.024), increased angle above reference plane of MRW (+2.64°, p<.001), decreased MCD (-11.6µm, p=.007), and decreased mean ALCSD (-18.91µm, p=.006). This is consistent with an increase in rim tissue thickness and a more anterior position of the ILM and ALCS relative to the BMO plane. Conversely, RNFLT change was not significantly different between trabeculectomy and control intervals (p=.37). Conclusion: Trabeculectomy resulted in anatomical changes to the ONH rim associated with reduced glaucomatous cupping. The RNFL thickness may be a more stable measure of disease progression that clinicians can use to monitor across time intervals containing glaucoma surgery.

Update on Micropulse Transscleral Cyclophotocoagulation.

Micropulse transscleral cyclophotocoagulation is a promising and relatively new technique that uses repetitive micropulses of diode laser energy, delivered with the Cyclo G6 Glaucoma Laser System (Iridex Corporation), in an off-and-on cyclical manner. This review article provides an update on the latest data available for this technique, including a discussion of the aspects in which there is still limited data, such as the precise mechanism of action, the ideal laser parameters based on total energy levels, as well as an overview of other potentially relevant variables that may be playing an important role in outcomes.

Micropulse Transscleral Cyclophotocoagulation: A Hypothesis for the Ideal Parameters.

MicroPulse transscleral cyclophotocoagulation (IRIDEX Corp., Mountain View, CA) is a novel technique that uses repetitive micropulses of active diode laser (On cycles) interspersed with resting intervals (Off cycles). It has been proposed that the OFF cycles allow thermal dissipation and, therefore, reduce collateral damage. The literature suggests that Micropulse has a better safety profile compared to traditional continuous-wave cyclophotocoagulation. However, because it is a relatively new technique, there are no clear guidelines stating the ideal laser parameters that would allow the best balance between high and sustained effectiveness with minimal side effects. This research reviewed the literature to approximate ideal parameters for single-session treatment. To simplify the comparison between studies, this study used Joules (J) as a way to standardize the energy levels employed. The reviewed clinical publications allowed reduction of these parameters to a range between 112 and 150 J of total energy, which allows a moderate IOP lowering effect of around 30% with few/no complications. An additional narrowing of the parameters was achieved after analyzing recently published experimental data. These data suggest a different mechanism of action for the Micropulse, similar to that of the pilocarpine. This effect was maximum at 150 J. Since clinical studies show few or no complications, even at those energy levels, it could be hypothesized that the ideal parameters can be located at a point closer to 150 J. This data also leads to the concept of dosimetry; the capacity to dose mTSCPC treatment based on desired IOP lowering effect and risk exposure. Further prospective studies are needed to test the proposed evidence-based hypothesis.