Pattern Electroretinogram Detects Localized Glaucoma Defects.

PURPOSE: We evaluated the clinical ability of pattern electroretinogram (PERG) to detect functional losses in the affected hemifield of open-angle glaucoma patients with localized perimetric defects. METHODS: Hemifield (horizontally-defined) steady-state PERGs (h-PERGs) were recorded in response to 1.7 c/deg alternating gratings from 32 eyes of 29 glaucomatous patients with a perimetric, focal one-hemifield defect, 10 eyes of 10 glaucomatous patients with a diffuse perimetric defect, and 18 eyes of 18 age-matched normal subjects. Standard automated perimetry (SAP) and spectral-domain optical coherence tomography (SD-OCT) for retinal nerve fiber layer (RNFL) thickness also were performed. h-PERG amplitudes and ratios, calculated corresponding hemifield perimetric deviations, as well as hemiretina RNFL thicknesses were analyzed. RESULTS: h-PERG amplitudes, perimetric deviations, and RNFL thicknesses showed losses (P < 0.001) when comparing affected with unaffected hemifields of localized glaucomatous eyes. No differences were found in h-PERG amplitudes between hemifields of normal or diffuse glaucomatous eyes. h-PERG amplitude ratios (affected/unaffected hemifield) in localized glaucoma were lower (P < 0.001) than the ratios from normal or diffuse glaucomatous eyes. The areas under the receiver operating characteristic curves for h-PERG amplitude ratios, comparing localized-defect glaucomatous eyes with normal or diffuse glaucomatous eyes, were 0.93 and 0.91, respectively. CONCLUSIONS: h-PERG assessment showed good diagnostic accuracy to confirm localized glaucomatous defects detected perimetrically. This test may be particularly useful in cognitively impaired patients or young/nonverbal patients unable to provide reliable visual fields. TRANSLATIONAL RELEVANCE: h-PERG provides a sensitive objective measure to confirm focal losses detected with SAP and/or RNFL thickness analysis.

Potential Effect of Cyclophosphamide on Bleb Survival in Five Patients with Multiple Sclerosis Who Underwent Glaucoma Surgery.

INTRODUCTION: The purpose of this case series was to report the potential role of cyclophosphamide (CY) on bleb survival and to evaluate the safety of the trabeculectomy procedure under immunosuppressant systemic therapy. CASE SERIES: Five eyes of five patients with unresponsive to intraocular pressure (IOP) lowering medication, progressive glaucoma, underwent mytomicin C (MMC) augmented phaco-trabeculectomy, performed by the same surgeon, A.G., during the period from May 2015 to January 2016. All patients were treated with low doses of systemic CY at the time of surgery, to control their relapsing progressive multiple sclerosis (MS) form. RESULTS: During a mean follow-up period of 20.6 ± 8.1 months, for cases of "complete success" (when the IOP was < 15 mmHg without glaucoma therapy) were observed, while one case was classified as a "qualified success" since the IOP was ≤ 15 mmHg with ß-blocker drops. There were no bleb infections, nor bleb-related complications. CONCLUSION: This study reports the safety of performing the filtration surgical procedure under immunosuppressant systemic therapy and provides a possible explication of CY anti-fibrotic mechanism and its possible role on bleb survival. Our findings may suggest new perspectives of study in this field.

ARCUATE NERVE FIBER LAYER CHANGES AFTER INTERNAL LIMITING MEMBRANE PEELING IN IDIOPATHIC EPIRETINAL MEMBRANE.

PURPOSE: To analyze the relationship between swelling of the arcuate nerve fiber layer (SANFL) and long-term decrease of retinal nerve fiber layer thickness after internal limiting membrane peeling for idiopathic epiretinal membrane, and to investigate if SANFL is related to a mechanical surgical damage. METHODS: Prospective, interventional consecutive case series of 46 eyes that underwent combined epiretinal membrane/internal limiting membrane peeling for idiopathic epiretinal membrane. Infrared, blue autofluorescence, color fundus imaging and measurement of retinal nerve fiber layer thickness in six peripapillary sectors by spectral-domain optical coherence tomography were performed preoperatively and at 2 weeks, 1, 3, 6, and 12 months after surgery. The presence of SANFL was checked postoperatively on infrared and blue autofluorescence fundus imaging, and the extent of each SANFL was measured on infrared fundus images. RESULTS: Areas of SANFL were identified in 39 eyes (84.8%) at 2-week follow-up. Retinal nerve fiber layer thickness significantly decreased in the temporal sectors at 1, 6, and 12 months (P < 0.0001). The linear extent of SANFL was significantly correlated with the percentage of reduction in retinal nerve fiber layer thickness in the temporal (R = 0.45; P < 0.0001) and infero-temporal (R = 0.23; P = 0.0008) sectors at 12 months of follow-up. Correspondence between sites of surgical grasping and the points of origin of SANFL was demonstrated on blue autofluorescence fundus images superimposed on intraoperative surgical frames. CONCLUSION: Early postoperative SANFL is correlated with late focal retinal nerve fiber layer thinning in the temporal sectors. Intraoperative surgical grasping seems to be a leading factor for the onset of SANFL.

Combined deep sclerectomy and descemet stripping automated endothelial keratoplasty.

PURPOSE: The aim of this study was to evaluate a novel surgical combination of Descemet stripping automated endothelial keratoplasty (DSAEK) and deep sclerectomy (DS) for the management of concomitant corneal endothelial decompensation and uncontrolled glaucoma. METHODS: This retrospective case series noncomparative study included 9 eyes of 6 consecutive patients with coexistence of corneal edema resulting from Fuchs dystrophy or pseudoexfoliation keratopathy and medically uncompensated glaucoma; these patients underwent combined DSAEK and DS with mitomycin C and an absorbable collagen implant. Corneal graft clarity, endothelial cell density, visual acuity, intraocular pressure (IOP), and identification of complications were assessed over a 2-year follow-up. RESULTS: All eyes obtained graft clarity throughout the follow-up, with a final average endothelial cell decrease of -36% from baseline, and showed improved vision and good IOP control without hypotensive therapy. Measured at 3 and 24 months postoperation, the mean visual acuity improvement was 154% and 372% and IOP decrease was 51.1% and 46.4%, respectively. Two anterior segment complications occurred in 2 (22%) patients' eyes. This consisted of a graft dislocation and a modest IOP elevation, treated successfully. CONCLUSIONS: Combined DSAEK and DS was longitudinally associated with good corneal graft survival and IOP control, with few complications. These findings suggest that this surgical approach is a viable option for patients with coexisting glaucoma and corneal endothelial dysfunction. Our study should stimulate a multicenter, randomized, controlled trial of our technique.

Underestimate of tonometric readings after photorefractive keratectomy increases at higher intraocular pressure levels.

PURPOSE: To determine whether tonometric readings of increases in intraocular pressure (IOP) during the water-drinking test (WDT) are affected by variations in central corneal thickness (CCT) induced by photorefractive keratectomy (PRK). METHODS: Data from 30 randomly selected eyes of 30 patients (18 men and 12 women; mean age, +/- SD: 33.9 +/- 7.6 years) undergoing bilateral PRK for myopia (-6.57 +/- 2.39 D) were obtained. Objective refraction, anterior radius of corneal curvature (R), CCT, and IOP measurements at baseline and at different time intervals after ingestion of 1 L of water within 5 minutes, were performed before and 6 months after PRK. All measured IOPs were recalculated by a correction factor for R and CCT and expressed as corrected intraocular pressure (IOPC) measurements. RESULTS: The mean R +/- SD was 7.84 +/- 0.20 and 8.76 +/- 0.34 mm, and the mean CCT was 544.83 +/- 19.69 and 453.97 +/- 29.95 microm, before and after PRK, respectively. The mean IOP at baseline was 15.05 +/- 2.78 and 9.83 +/- 2.56 mm Hg, and during WDT was 18.32 +/- 3.42 and 11.42 +/- 3.10 mm Hg at 10 minutes, 18.59 +/- 2.99 and 11.54 +/- 2.54 mm Hg at 20 minutes, 17.80 +/- 2.85 and 10.87 +/- 2.22 mm Hg at 30 minutes, 16.35 +/- 3.02 and 10.26 +/- 2.21 mm Hg at 45 minutes, and 14.90 +/- 2.52 and 9.81 +/- 2.32 mm Hg at 60 minutes, before and after PRK, respectively. The mean IOPC at baseline was 13.64 +/- 2.33 and 13.05 +/- 2.98 mm Hg, and during WDT was 16.61 +/- 2.77 and 15.08 +/- 3.59 mm Hg at 10 minutes, 16.96 +/- 2.69 and 15.33 +/- 2.96 mm Hg at 20 minutes, 16.10 +/- 2.50 and 14.42 +/- 2.60 mm Hg at 30 minutes, 14.92 +/- 2.72 and 13.62 +/- 2.65 mm Hg at 45 minutes, 13.82 +/- 2.27 and 13.05 +/- 2.55 mm Hg at 60 minutes, before and after excimer laser treatment, respectively. Pre- and postoperative IOPs and percentages of IOP increase differed significantly (P < 0.05), in particular at the peak, as did IOPCs but not the percentages of increase in IOPC, apart from the highest values. CONCLUSIONS: Corneal changes after PRK for myopia may induce an uneven underestimate of the IOP increases. The inadequacy of a correction factor to compensate for CCT and R at high IOP levels indicates that other biomechanical factors may play a role when the cornea is subjected to dynamic actual IOP variation. Such increase of the well-known underestimate of IOP after PRK at higher actual IOPs may have significant clinical implications in tonometric assessment of subjects at risk of glaucomatous damage.