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.

Barriers to Receiving Follow-Up Eye Care and Detection of Non-Glaucomatous Ocular Pathology in the Philadelphia Glaucoma Detection and Treatment Project.

This cross-sectional study aimed to evaluate adherence rates and identify barriers to receiving follow-up eye care in participants diagnosed with significant non-glaucomatous eye pathology in the Philadelphia Glaucoma Detection and Treatment Project. This community-based project aimed to improve detection, management, treatment, and follow-up eye care of individuals at high risk for glaucoma in community-based settings. Participants throughout Philadelphia, Pennsylvania, USA were enrolled. After a comprehensive eye examination, follow-up recommendations were given to each participant. A telephone survey was administered to individuals diagnosed with non-glaucomatous ocular pathology 3 months after initial eye examination to assess rates of follow-up and to evaluate potential barriers to follow-up. Of the 1649 participants enrolled in this project, 249 (15 %) were diagnosed with significant non-glaucomatous ocular pathology requiring follow-up care. There were 143 (57 %) who responded to the telephone survey. Respondents had a median age of 72 years, and were predominately female (69 %) and African-American (64 %). Of the respondents, 36 (25 %) attended a follow-up appointment. Participants who did not remember the results of their examinations, did not remember their recommendations, and had not seen an eye doctor within the past year were less likely to make a follow-up appointment (P = 0.04, 0.001 and 0.005, respectively). The Philadelphia Glaucoma Detection and Treatment Program was able to detect a significant amount of non-glaucomatous ocular pathology requiring follow-up care. Actual follow-up rates were sub-optimal. Further research is needed to determine interventions to overcome barriers and increase adherence with follow-up recommendations.

Outcomes of Sequential Glaucoma Drainage Implants in Refractory Glaucoma.

PURPOSE: To describe the outcomes of eyes that have undergone a second glaucoma drainage implant (GDI) surgery. METHODS: A retrospective review of eyes that underwent a second GDI surgery from 2006 to 2013 was conducted. Primary outcome measures included intraocular pressure (IOP) reduction and success rates. Secondary outcome measures included glaucoma medication use, visual acuity, and number of reoperations. Success was defined as 6 ≤ IOP ≤ 21 with at least 20% IOP reduction, and no increase in the number of glaucoma medications from baseline at 3 months of follow-up or more. RESULTS: Sixty-five eyes (63 patients) had a mean follow-up of 22.4 ± 19.9 months. The most frequently placed second GDIs were an Ahmed FP7 (49%) or a Baerveldt 250 (26%) in the inferotemporal (46%) or inferonasal (35%) quadrant. At 3-year follow-up, IOP was reduced from 25.8 ± 7.7 to 17.4 ± 9.9 mm Hg (P = 0.004) and the number of glaucoma medications decreased from 3.6 ± 1.2 to 2.5 ± 1.4 (P = 0.01) compared with baseline. The median time to failure was 24.7 ± 5.8 months. There was no significant difference in failure rates for type of sequential GDI (P = 0.80) or plate location (P = 0.34). There was no significant difference in visual acuity between baseline and 3-year follow-up (P = 1.0). The most common postoperative complication was corneal edema (n = 9, 14%). CONCLUSIONS: Most eyes undergoing a second GDI achieve adequate IOP control with fewer antiglaucoma medications. Failure rates were similar regardless of quadrant selection or GDI type.

Tube shunt coverage with gamma-irradiated cornea allograft (VisionGraft).

PURPOSE: To investigate the clinical outcomes of tube shunt coverage using sterile gamma-irradiated cornea allograft. PATIENTS AND METHODS: The Wills Eye Hospital Glaucoma Research Center retrospectively reviewed the medical records of 165 patients who underwent glaucoma tube shunt procedures using sterile gamma-irradiated cornea allograft (VisionGraft) between December 2012 and November 2013. Demographic characteristics, type of tube shunt, and position were noted. Complications were recorded at 1 day; 1 week; 1, 3, 6, and 12 months; and on the final postoperative visit. RESULTS: One hundred and sixty-nine eyes of 165 patients were included. The mean follow-up time was 4.8±3.5 (ranging from 1 to 16) months. There was no evidence of immunological reaction, infection, or exposure in 166 eyes (98.2%). Three eyes (1.8%) experienced graft or tube exposure within the first 3 postoperative months. Two of the cases had underlying diseases: bullous pemphigoid and chronic allergic conjunctivitis. CONCLUSION: Coverage of tube shunts using gamma-irradiated cornea allograft had a low exposure rate and was well tolerated. The graft can be stored long term at room temperature and has an excellent postoperative cosmetic appearance.

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.

Radiographic analysis of extraocular muscle volumetric changes in thyroid-related orbitopathy following orbital decompression.

PURPOSE: To evaluate radiographic volume changes in extraocular muscles (EOM) following orbital decompression for thyroid-related orbitopathy (TRO). METHODS: Medical records of 22 orbits in 12 patients undergoing postoperative orbital CT after orbital decompression for TRO were retrospectively reviewed. All orbits demonstrated no signs of clinical reactivation of TRO. EOM volumes were determined by the summation of each EOM's cross-sectional area in the coronal plane of the CT scans and multiplying the sum by the slice thickness. Main outcome measure was a comparison of EOM volumes preoperatively and postoperatively. RESULTS: All orbits demonstrated proptosis reduction postoperatively with a mean of 4.8 mm +/- 2.1 mm (p < 0.0001). The significant increase in the medial rectus muscle (p = 0.0010) postoperatively accounted for the primary change in the postoperative enlargement of total EOM volume (p = 0.028). The medial rectus muscle increased 27% from the preoperative volume. The lateral rectus, superior rectus/levator complex, inferior rectus, and superior oblique muscles did not demonstrate a significant volume increase postoperatively (p = 0.23, 0.21, 0.17, 0.40, respectively). Two patients who underwent unilateral orbital decompression demonstrated EOM enlargement postoperatively in the operative orbit only. CONCLUSIONS: There is a significant increase in medial rectus muscle volume postoperatively in orbits undergoing orbital decompression for TRO despite lacking clinical evidence of disease reactivation.

Adenosine suppresses exocytosis from cone terminals of the salamander retina.

In the retina, adenosine is released in the dark and has been shown to inhibit Ca2+ influx through voltage-gated Ca2+ channels in cones. Therefore, we tested whether adenosine can inhibit exocytosis from isolated cone photoreceptors. Simultaneous measurements of membrane exocytosis and Ca2+ were made from cones using the activity-dependent dye, Synaptored-C2, and the Ca2+ indicator dye, Fluo-4. Adenosine suppressed exocytosis in cones, indicating that transmitter release is also reduced from cone terminals, and further supports an inhibitory mechanism for modulating transmitter release onto second-order neurons. Furthermore, this raises the possibility that adenosine might be neuroprotective for photoreceptors and second-order neurons by suppressing Ca2+ levels in cones and reducing exocytosis of L-glutamate, respectively.

Adenosine inhibits voltage-dependent Ca2+ influx in cone photoreceptor terminals of the tiger salamander retina.

Endogenous adenosine has already been shown to inhibit transmitter release from the rod synapse by suppressing Ca(2+) influx through voltage-gated Ca(2+) channels. However, it is not clear how adenosine modulates the cone synapse. Cone photoreceptors, like rod photoreceptors, also possess L-type Ca(2+) channels that regulate the release of L-glutamate. To assess the impact of adenosine on Ca(2+) influx though voltage-gated Ca(2+) channels in cone terminals, whole-cell perforated-patch clamp recording and Ca(2+) imaging with fluo-4 were used on isolated cones and salamander retinal slices. Synaptic markers (VAMP and piccolo) and activity-dependent dye labeling revealed that tiger salamander cone terminals contain a broad, vesicle-filled cytoplasmic extension at the base of the somatic compartment, which is unlike rod terminals that contain one or more thin axons, each terminating in a large bulbous synaptic terminal. The spatiotemporal Ca(2+) responses of the cone terminals do not differ significantly from the Ca(2+) responses of the soma or inner segment like that observed in rods. Whole-cell recording of cone I(Ca) and Ca(2+) imaging of synaptic terminals in cones demonstrate that adenosine inhibited both I(Ca) and the depolarization-evoked Ca(2+) increase in cone terminals in a dose-dependent manner from 1 to 50 muM. These results indicate that, as in rods, adenosine's ability to suppress voltage-dependent Ca(2+) channels at the cone synapse will limit the amount of L-glutamate released. Therefore, adenosine has an inhibitory effect on L-glutamate release at the first synapse, which likely favors elevated adenosine levels in the dark or during dark-adapted conditions.