David G. Godfrey

Glaucoma Diagnostic Accuracy of Ganglion Cell–Inner Plexiform Layer Thickness: Comparison with Nerve Fiber Layer and Optic Nerve Head

PURPOSE To determine the diagnostic performance of macular ganglion cell-inner plexiform layer (GCIPL) thickness measured with the Cirrus high-definition optical coherence tomography (HD-OCT) ganglion cell analysis (GCA) algorithm (Carl Zeiss Meditec, Dublin, CA) to discriminate normal eyes and eyes with early glaucoma and to compare it with that of peripapillary retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) measurements. DESIGN Evaluation of diagnostic test or technology. PARTICIPANTS Fifty-eight patients with early glaucoma and 99 age-matched normal subjects. METHODS Macular GCIPL and peripapillary RNFL thicknesses and ONH parameters were measured in each participant, and their diagnostic abilities were compared. MAIN OUTCOME MEASURES Area under the curve (AUC) of the receiver operating characteristic. RESULTS The GCIPL parameters with the best AUCs were the minimum (0.959), inferotemporal (0.956), average (0.935), superotemporal (0.919), and inferior sector (0.918). There were no significant differences between these AUCs and those of inferior quadrant (0.939), average (0.936), and superior quadrant RNFL (0.933); vertical cup-to-disc diameter ratio (0.962); cup-to-disc area ratio (0.933); and rim area (0.910), all P>0.05. CONCLUSIONS The ability of macular GCIPL parameters to discriminate normal eyes and eyes with early glaucoma is high and comparable to that of the best peripapillary RNFL and ONH parameters. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

Prevalence of ocular surface complaints in patients with glaucoma using topical intraocular pressure-lowering medications.

Purpose: To determine the prevalence of ocular surface disease (OSD) in patients with glaucoma using topical intraocular pressure (IOP)-lowering therapy. Methods: This prospective observational study enrolled patients with primary open-angle glaucoma or ocular hypertension who were on a topical IOP-lowering medication regimen. Enrolled patients completed the ocular surface disease index (OSDI) and OSDI scores (0-100, with 0 representing no symptoms) were calculated for each patient. Medical history, demographics, and concomitant medication information were also collected. Results: Overall, 630 patients from 10 sites participated. Of these, 305 patients (48.4%) had an OSDI score indicating either mild (n = 134, 21.3%), moderate (n = 84, 13.3%), or severe (n = 87, 13.8%) OSD symptoms. OSDI scores were significantly different between patients with and without a prior diagnosis of dry eye syndrome (25.2 ± 15.4 vs 15.4 ± 15.8, respectively; P = 0.0036) and between patients who did and did not use artificial tears at the time of study participation (23.0 ± 15.6 vs 15.3 ± 15.8, respectively; P = 0.0046). Mean OSDI scores varied significantly with the number of topical IOP-lowering medications used, with higher (more severe) OSDI scores in patients using multiple IOP-lowering medications. Specifically, patients on a single medication had a mean OSDI score of 12.9 ± 13.1, which was significantly lower than those of patients on 2 (16.7 ± 17.0; P = 0.007) or 3 medications (19.4 ± 18.1; P = 0.0001). Conclusions: OSD is prevalent among medically treated patients with glaucoma. The severity of OSD symptoms is positively correlated to the number of IOP-lowering medications used.

Treatment Outcomes in the Ahmed Baerveldt Comparison Study after 1 Year of Follow-up

PURPOSE To determine the relative efficacy and complications of the Ahmed glaucoma valve (AGV) model FP7 (New World Medical, Ranchos Cucamonga, CA) and the Baerveldt glaucoma implant (BGI) model 101-350 (Abbott Medical Optics, Abbott Park, IL) in refractory glaucoma. DESIGN Multicenter, randomized, controlled clinical trial. PARTICIPANTS Two hundred seventy-six patients, including 143 in the AGV group and 133 in the BGI group. METHODS Patients 18 to 85 years of age with refractory glaucoma having intraocular pressure (IOP) of 18 mmHg or more in whom an aqueous shunt was planned were randomized to undergo implantation of either an AGV or a BGI. MAIN OUTCOME MEASURES The primary outcome was failure, defined as IOP >21 mmHg or not reduced by 20% from baseline, IOP ≤5 mmHg, reoperation for glaucoma or removal of implant, or loss of light perception vision. Secondary outcomes included mean IOP, visual acuity, use of supplemental medical therapy, and complications. RESULTS Preoperative IOP (mean±standard deviation [SD]) was 31.2±11.2 mmHg in the AGV group and 31.8±12.5 mmHg in the BGI group (P = 0.71). At 1 year, mean±SD IOP was 15.4±5.5 mmHg in the AGV group and 13.2±6.8 mmHg in the BGI group (P = 0.007). The mean±SD number of glaucoma medications was 1.8±1.3 in the AGV group and 1.5±1.4 in the BGI group (P = 0.071). The cumulative probability of failure was 16.4% (standard error [SE], 3.1%) in the AGV group and 14.0% (SE, 3.1%) in the BGI group at 1 year (P = 0.52). More patients experienced early postoperative complications in the BGI group (n = 77; 58%) compared with the AGV group (n = 61; 43%; P = 0.016). Serious postoperative complications associated with reoperation, vision loss of ≥2 Snellen lines, or both occurred in 29 patients (20%) in the AGV group and in 45 patients (34%) in the BGI group (P = 0.014). CONCLUSIONS Although the average IOP after 1 year was slightly higher in patients who received an AGV, there were fewer early and serious postoperative complications associated with the use of the AGV than the BGI.

Intermediate-term outcomes of 350-mm2 baerveldt glaucoma implants

OBJECTIVE To determine the intermediate-term outcome of 350-mm(2) Baerveldt glaucoma implants. DESIGN Retrospective, noncomparative case series. PARTICIPANTS Sixty-five patients (65 eyes). INTERVENTION Implantation of 350-mm(2) Baerveldt glaucoma drainage device. MAIN OUTCOME MEASURES Intraocular pressure, number of glaucoma medications, best-corrected Snellen visual acuity, length of follow-up, risk factors for failure, and complications. RESULTS Mean intraocular pressure was reduced from a preoperative value of 32 mmHg to a 2-year postoperative value of 14 mmHg (56% reduction, P < 0.001). Success rates at 2-year follow-up were 71%, 81%, 78%, 60%, and 47% for the overall group, primary open-angle glaucoma group, neovascular group, uveitic group, and other group, respectively. After accounting for the effect of diagnosis group, significant risk factors in the overall group for failure at 2 years included younger age, high preoperative intraocular pressure, and more prior incisional surgeries. Glaucoma medication use in our overall study population was reduced from 2.5 mean preoperative medications to 0.8 postoperative medications (68%). Median change in Snellen visual acuity between preoperative and 2-year postoperative visits was not significant in the overall group. Postoperative complications included choroidal effusion in 15 patients (23%), tube obstruction by blood or vitreous in five patients (8%), phthisis in four patients (6%), aqueous misdirection in two patients (3%), strabismus in two patients (3%), tube-cornea touch in two patients (3%), endophthalmitis in two patients (3%), and retinal detachment in two patients (3%). No patients had suprachoroidal hemorrhage. CONCLUSIONS The 350-mm(2) Baerveldt glaucoma implants are a safe and effective treatment for intermediate-term intraocular pressure control in patients with refractory glaucoma.

Three-year Treatment Outcomes in the Ahmed Baerveldt Comparison Study

PURPOSE To compare 3-year outcomes and complications of the Ahmed FP7 Glaucoma Valve (AGV) (New World Medical, Cucamonga, CA) and the Baerveldt Glaucoma Implant (BGI) 101-350 (Abbott Medical Optics, Abbott Park, IL) for the treatment of refractory glaucoma. DESIGN Multicenter, randomized, controlled clinical trial. PARTICIPANTS A total of 276 patients: 143 in the AGV group and 133 in the BGI group. METHODS Patients aged 18 to 85 years with refractory glaucoma and intraocular pressures (IOPs) ≥ 18 mmHg in whom an aqueous shunt was planned were randomized to an AGV or a BGI. MAIN OUTCOME MEASURES The IOP, visual acuity (VA), supplemental medical therapy, complications, and failure (IOP >21 mmHg or not reduced by 20% from baseline, IOP <5 mmHg, reoperation for glaucoma or removal of implant, or loss of light perception vision). RESULTS At 3 years, IOP (mean ± standard deviation) was 14.3 ± ± 4.7 mmHg (AGV group) and 13.1 ± 4.5 mmHg (BGI group) (P = 0.086) on 2.0 ± 1.4 and 1.5 ± 1.4 glaucoma medications, respectively (P = 0.020). The cumulative probabilities of failure were 31.3% (standard error [SE], 4.0%) (AGV) and 32.3% (4.2%) (BGI) (P = 0.99). Postoperative complications associated with reoperation or vision loss of >2 Snellen lines occurred in 24 patients (22%) (AGV) and 38 patients (36%) (BGI) (P = 0.035). The mean change in the logarithm of the minimum angle of resolution VA at 3 years was similar (AGV: 0.21 ± 0.88, BGI: 0.26 ± 0.74) in the 2 treatment groups at 3 years (P = 0.66). The cumulative proportion of patients (SE) undergoing reoperation for glaucoma before the 3-year postoperative time point was 14.5% (3.0%) in the AGV group compared with 7.6% (2.4%) in the BGI group (P = 0.053, log rank). The relative risk of reoperation for glaucoma in the AGV group was 2.1 times that of the BGI group (95% confidence interval, 1.0-4.8; P = 0.045, Cox proportional hazards regression). CONCLUSIONS Implantation of the AGV was associated with the need for significantly greater adjunctive medication to achieve equal success relative to implantation of the BGI and resulted in a greater relative risk of reoperation for glaucoma. More subjects experienced serious postoperative complications in the BGI group than in the AGV group.

Diagnostic performance of optical coherence tomography ganglion cell-inner plexiform layer thickness measurements in early glaucoma

PURPOSE To evaluate the glaucoma diagnostic performance of ganglion cell inner-plexiform layer (GCIPL) parameters used individually and in combination with retinal nerve fiber layer (RNFL) or optic nerve head (ONH) parameters measured with Cirrus HD-OCT (Carl Zeiss Meditec, Inc, Dublin, CA). DESIGN Prospective cross-sectional study. PARTICIPANTS Fifty patients with early perimetric glaucoma and 49 age-matched healthy subjects. METHODS Three peripapillary RNFL and 3 macular GCIPL scans were obtained in 1 eye of each participant. A patient was considered glaucomatous if at least 2 of the 3 RNFL or GCIPL scans had the average or at least 1 sector measurement flagged at 1% to 5% or less than 1%. The diagnostic performance was determined for each GCIPL, RNFL, and ONH parameter as well as for binary or-logic and and-logic combinations of GCIPL with RNFL or ONH parameters. MAIN OUTCOME MEASURES Sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR). RESULTS Among GCIPL parameters, the minimum had the best diagnostic performance (sensitivity, 82.0%; specificity, 87.8%; PLR, 6.69; and NLR, 0.21). Inferior quadrant was the best RNFL parameter (sensitivity, 74%; specificity, 95.9%; PLR, 18.13; and NLR, 0.27), as was rim area (sensitivity, 68%; specificity, 98%; PLR, 33.3; and NLR, 0.33) among ONH parameters. The or-logic combination of minimum GCIPL and average RNFL provided the overall best diagnostic performance (sensitivity, 94%; specificity, 85.7%; PRL, 6.58; and NLR, 0.07) as compared with the best RNFL, best ONH, and best and-logic combination (minimum GCIPL and inferior quadrant RNFL; sensitivity, 64%; specificity, 100%; PLR, infinity; and NPR, 0.36). CONCLUSIONS The binary or-logic combination of minimum GCIPL and average RNFL or rim area provides better diagnostic performances than those of and-logic combinations or best single GCIPL, RNFL, or ONH parameters. This finding may be clinically valuable for the diagnosis of early glaucoma.

Canal surgery in adult glaucomas.

Purpose of review Outflow procedures for glaucoma surgery have remained popular in the last decade, including trabeculectomy, glaucoma drainage devices, and deep sclerectomy/viscocanalostomy. In the last few years, the surgical armamentarium for glaucoma has vastly increased. Surgeons are using more procedures aimed at creating bleb-free surgery. Schlemms canal surgery is experiencing a renaissance. This article concentrates on three of the more commonly performed canal procedures: trabeculotomy ab interno (Trabectome), Canaloplasty, and trabeculotomy ab externo. Recent findings Trabeculotomy ab interno performed with the Trabectome has been shown to lower intraocular pressure (IOP) almost 40% by 12 months with minimal complications. Trabectome alone, as well as combined with cataract surgery, appears to lower IOP quite well. Canaloplasty has also been shown to lower IOP by 38% and combined with cataract surgery, IOP was lowered 44% at 24 months. Trabeculotomy lowers IOP well, especially in older adults. Phacotrabeculotomy lowers IOP to 21 mmHg or less in 84% of patients with supplemental use of medications, and in 36% of patients without at 3 years. Summary Canal surgery has proven to be an alternative to traditional glaucoma surgery, lowering IOP relatively well. Surgeons must be comfortable with the anatomy and proceed with the procedure in eyes that are amenable to various new surgical advances.

Central corneal thickness in patients with congenital aniridia.

Purpose. To compare the mean central corneal thickness (CCT) in patients with congenital aniridia to that of a group of age-matched control subjects. The findings of specular and confocal microscopy in a patient with aniridia are discussed. Methods. The mean values of five consecutive pachymetry measurements of patients with aniridia and control subjects were used for analysis. Statistical analysis was performed with a Mann–Whitney rank sum test. Specular microscopy was performed on one patient with aniridia using a Konan Specular Microscope Noncon ROBO CA (Hyogo, Japan). Confocal microscopy through focusing was performed with the Tandem Scanning Confocal Microscope (Reston, VA). Results. Mean CCT measured 691.8 ± 75.4 μm for patients with aniridia (16 eyes of 10 patients) and 548.2 ± 21.2 μm for control subjects (P<0.001). Specular microscopy in a patient with aniridia showed normal endothelial cell counts and structure. Confocal microscopy through focusing of this patient showed normal-appearing keratocytes and a thick corneal stroma. Conclusions. Patients with congenital aniridia have significantly thicker corneas than do age-matched control subjects. This difference can have important implications for the treatment of those patients who develop secondary glaucoma. The increased CCT in patients with aniridia is not a result of endothelial dysfunction but appears to be the result of the production of a thickened but otherwise healthy cornea by the mutated PAX6 gene.

Postoperative Complications in the Ahmed Baerveldt Comparison Study During Five Years of Follow-up

PURPOSE To compare the late complications in the Ahmed Baerveldt Comparison Study during 5 years of follow-up. DESIGN Multicenter, prospective randomized clinical trial. METHODS setting: Sixteen international clinical centers. STUDY POPULATION Two hundred seventy-six subjects aged 18-85 years with previous intraocular surgery or refractory glaucoma with intraocular pressure of >18 mm Hg. INTERVENTIONS Ahmed Glaucoma Valve FP7 or Baerveldt Glaucoma Implant BG 101-350. MAIN OUTCOME MEASURES Late postoperative complications (beyond 3 months), reoperations for complications, and decreased vision from complications. RESULTS Late complications developed in 56 subjects (46.8 ± 4.8 5-year cumulative % ± SE) in the Ahmed Glaucoma Valve group and 67 (56.3 ± 4.7 5-year cumulative % ± SE) in the Baerveldt Glaucoma Implant group (P = .082). The cumulative rates of serious complications were 15.9% and 24.7% in the Ahmed Glaucoma Valve and Baerveldt Glaucoma Implant groups, respectively (P = .034), although this was largely driven by subjects who had tube occlusions in the 2 groups (0.8% in the Ahmed Glaucoma Valve group and 5.7% in the Baerveldt Glaucoma Implant group, P = .037). Both groups had a relatively high incidence of persistent diplopia (12%) and corneal edema (20%), although half of the corneal edema cases were likely due to pre-existing causes other than the aqueous shunt. The incidence of tube erosion was 1% and 3% in the Ahmed Glaucoma Valve and Baerveldt Glaucoma Implant groups, respectively (P = .04). CONCLUSIONS Long-term rates of vision-threatening complications and complications resulting in reoperation were higher in the Baerveldt Glaucoma Implant than in the Ahmed Glaucoma Valve group over 5 years of follow-up.

Gonioscopy assisted transluminal trabeculotomy: an ab interno circumferential trabeculotomy for the treatment of primary congenital glaucoma and juvenile open angle glaucoma.

Background/aims To introduce a novel ab interno 360° trabeculotomy for treating primary congenital glaucoma (PCG) and juvenile open angle glaucoma (JOAG) and report preliminary results. Methods A retrospective chart review of patients who underwent a gonioscopy assisted transluminal trabeculotomy (GATT) procedure by four of the authors (DSG, OS, RLF and DGG) between October 2011 and October 2013. The surgery was performed in patients ≤30 years old with a dysgenic anterior segment angle and uncontrolled PCG and JOAG. Results Fourteen eyes of 10 patients underwent GATT with follow-up >12 months (12–33 months; mean 20.4). Patients ranged in age from 17 months to 30 years (mean=18.4 years), and five (50%) were female patients. No complications occurred during or following surgery except for early postoperative hyphema in five (36%) of eyes, all cleared by 1 month. The mean intraocular pressure (IOP) decreased from 27.3 to 14.8 mm Hg and the mean number of medications required decreased from 2.6 to 0.86. Five eyes had a drop in IOP ≥15 mm Hg (range 15–39). Conclusions The preliminary results and safety for GATT, a minimally invasive conjunctival sparing circumferential trabeculotomy, are promising and at least equivalent to previous results for ab externo trabeculotomy for the treatment of PCG and JOAG. All eyes in the study were considered a clinical success.