Reproducibility of minimum rim width and retinal nerve fibre layer thickness using the Anatomic Positioning System in glaucoma patients.

OBJECTIVE: To determine the test-retest repeatability of minimum rim width and retinal nerve fibre layer thickness measurements obtained by spectral-domain optical coherence tomography using the Anatomic Positioning System protocol in glaucoma patients and controls. Also, to assess the ability of the minimum rim width and retinal nerve fibre layer thickness to diagnose glaucoma in 2 circular peripapillary locations. METHODS: Spectral domain optical coherence tomography scans of the optic nerve head were obtained twice during the same visit using the Anatomic Positioning System eye-tracking protocol. The minimum rim width and retinal nerve fibre layer thickness were measured at 3 circular diameters (3.5 mm, 4.1 mm, and 4.7 mm). Intraclass correlation coefficients and area under the receiver operating characteristic were calculated for these parameters. RESULTS: A total of 36 glaucomatous eyes and 59 control eyes were included in the analysis. The intraclass correlation coefficients of minimum rim width and retinal nerve fibre layer thickness global measurement for 3.5 mm and 4.1 mm circles ranged between 0.98 and 1.00 and for 4.7 mm circle was between 0.76 and 1.00. The minimum rim width had an area under the receiver operating characteristic of 0.97, while the retinal nerve fibre layer thickness measurements had an area under the receiver operating characteristic of 0.95, 0.95, and 0.96 for the 3.5 mm, 4.1 mm, and 4.7 mm circles, respectively. CONCLUSIONS: The minimum rim width and retinal nerve fibre layer thickness measurements using the Anatomic Positioning System protocol had overall excellent reproducibility and diagnostic performance. Using this protocol and the novel minimum rim width parameter may be useful in more accurate diagnosis and follow-up of patients with glaucoma.

Adherence to Follow-up Recommendations Among Individuals in the Philadelphia Glaucoma Detection and Treatment Project.

PURPOSE: To evaluate rates of adherence to free follow-up eye exam appointments among participants in the Philadelphia Glaucoma Detection and Treatment Project. PATIENTS AND METHODS: Ophthalmologists and testing equipment were brought directly to participants at risk for glaucoma at 43 community sites in Philadelphia. Those diagnosed with glaucoma-related pathology were recommended to return for follow-up to be reexamined on site. Rates of adherence and clinical and demographic risk factors for adherence were evaluated. RESULTS: Five hundred thirty-one participants were diagnosed with glaucoma-related conditions and recommended to attend community-based follow-up exams. Follow-up adherence rate was 61.2% (n=325/531). Significant factors associated with greater eye exam appointment adherence, based on our univariable analysis, included final diagnosis of glaucoma (risk ratio [RR]=1.33; 95% confidence interval [CI], 1.13-1.57), male sex (RR=1.19; 95% CI, 1.04-1.36), white race (RR=1.26; 95% CI, 1.08-1.48), age (RR=1.17; 95% CI, 1.00-1.37) recommendation for glaucoma medication (RR=1.52; 95% CI, 1.35-1.71), recommendation for laser peripheral iridotomy (RR=1.18; 95% CI, 1.02-1.35), diagnosis of age-related macular degeneration (RR=1.42; 95% CI, 1.13-1.77) and an increased intraocular pressure (>22 mm Hg in the worse eye) (RR=1.23; 95% CI, 1.06-1.42). On the basis of our multivariable model, diagnosis, sex, and recommended glaucoma medications were significantly associated with follow-up adherence. CONCLUSIONS: This study demonstrates that individuals living in underserved urban communities would take advantage of free eye exams in community sites and return for follow-up eye exams in these same settings. Future studies could investigate interventions to improve eye exam appointment adherence in community-based settings to detect glaucoma-eye conditions.

Impossibility to eliminate observer effect in the assessment of adherence in clinical trials.

PURPOSE: To utilize the Travoprost Dosing Aid (DA) in the assessment of patient medication adherence, while also determining whether or not altering the functionality of the DA in three randomized subject groups can reduce observer effect. METHODS: Forty-five subjects were randomized into three groups: two with monitored DAs and one without monitoring. One group of subjects was given a DA that both monitored drop usage and had visual and audible alarms, while the other monitored group included subjects given a DA that had no alarms but continued to monitor drop usage. The third group was given a DA that had no alarm reminders or dose usage monitoring. Subjects were informed that some monitors would not be functional, in an attempt to reduce observer effect, or the effect of being monitored on subject behavior and adherence. A six-item questionnaire was also utilized to assess how the subjects felt about their adherence and DA use. RESULTS: The overall adherence rates were found to be 78% in the fully functional group (95% confidence interval: 70-88) and 76% in the no alarms group (95% confidence interval: 65-89). No association was seen between questionnaire response and medication adherence. The patients in the DA group without alarms had a significantly higher odds ratio of medication adherence if they reported on the questionnaire that using the DA did affect how much they used their drops. CONCLUSION: Though the use of DA was expected to reveal different rates of adherence depending on the functionality of the DA between groups, patients with a nonfunctioning DA did not have a significant difference in medication adherence compared to those given a fully functional DA. This supports that an observer effect was not reduced despite these interventions, and that the subjects adhered to taking their medications as if they had a functioning DA and were being monitored.

Explantation of the novel Ahmed glaucoma valve M4 implant.

PURPOSE: To report a series of cases involving Ahmed Glaucoma Valve M4 (AGV) explantation and to discuss the surgical technique to remove the drainage device. METHODS: Four cases were identified that presented with AGV M4 postoperative complications necessitating tube shunt removal. Three patients presented with conjunctival erosion and 1 patient with persistent diplopia. AGV M4 implants were removed successfully between 1.5 and 9 months after implantation. RESULTS: Successful explantation of the AGV M4 novel implant was achieved in all cases without intraoperative or postoperative complications. CONCLUSIONS: If necessary, AGV M4 explantation can be successfully performed in the early postoperative period.