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J S Schuman

Publications and source records attributed to J S Schuman.

At least 19 recordsLinked to original sources
PubMed2006

Location of glaucoma drainage devices relative to the optic nerve.

BACKGROUND: Limited data are available to guide optimal positioning of glaucoma drainage devices (GDD) in relation to the limbus and optic nerve. The authors aim to provide guidelines for appropriate and safe GDD implantation. METHOD: The optimal positioning of five different GDD were evaluated using necropsy eyes of varying axial lengths. The dependent variable that was measured was the maximum distance that a GDD could be placed posterior to the limbus while remaining 2 mm away from the optic nerve. RESULTS: The average maximum distance posterior to the limbus of the anterior plate edge ranged between 9.0-15.0 mm in the superotemporal quadrant for the GDD tested. The distances for superonasal, inferonasal, and inferotemporal quadrants ranged between 8.0-14.0 mm, 9.0-14.0 mm, and 11.0-17.0 mm, respectively. The Molteno device could be placed most posteriorly while remaining 2 mm away from the nerve. The Ahmed FP7 and S2 were the least amenable to posterior placement before encroaching on the 2 mm limit. CONCLUSION: The maximum distance that a GDD can be placed posterior to the limbus, before encroachment around the optic nerve, varies between different devices and quadrants of placement. Taking a measurement of the exact distance of the plate from the limbus during GDD surgery is recommended.

Eye↗
PubMed2006

A new quality assessment parameter for optical coherence tomography.

AIM: To create a new, automated method of evaluating the quality of optical coherence tomography (OCT) images and to compare its image quality discriminating ability with the quality assessment parameters signal to noise ratio (SNR) and signal strength (SS). METHODS: A new OCT image quality assessment parameter, quality index (QI), was created. OCT images (linear macular scan, peripapillary circular scan, and optic nerve head scan) were analysed using the latest StratusOCT system. SNR and SS were collected for each image. QI was calculated based on image histogram information using a software program of our own design. To evaluate the performance of these parameters, the results were compared with subjective three level grading (excellent, acceptable, and poor) performed by three OCT experts. RESULTS: 63 images of 21 subjects (seven each for normal, early/moderate, and advanced glaucoma) were enrolled in this study. Subjects were selected in a consecutive and retrospective fashion from our OCT imaging database. There were significant differences in SNR, SS, and QI between excellent and poor images (p = 0.04, p = 0.002, and p<0.001, respectively, Wilcoxon test) and between acceptable and poor images (p = 0.02, p<0.001, and p<0.001, respectively). Only QI showed significant difference between excellent and acceptable images (p = 0.001). Areas under the receiver operating characteristics (ROC) curve for discrimination of poor from excellent/acceptable images were 0.68 (SNR), 0.89 (IQP), and 0.99 (QI). CONCLUSION: A quality index such as QI may permit automated objective and quantitative assessment of OCT image quality that performs similarly to an expert human observer.

Aged↗
PubMed2006

Ultrahigh resolution optical coherence tomography in non-exudative age related macular degeneration.

AIM: To describe the appearance of the non-exudative forms of age related macular degeneration (AMD) as imaged by ultrahigh resolution optical coherence tomography (UHR-OCT). METHODS: A UHR-OCT ophthalmic imaging system, which utilises a femtosecond laser light source capable of approximately 3 mum axial resolution, was employed to obtain retinal cross sectional images of patients with non-exudative AMD. Observational studies of the resulting retinal images were performed. RESULTS: 52 eyes of 42 patients with the clinical diagnosis of non-exudative AMD were imaged using the UHR-OCT system. 47 of the 52 (90%) eyes had the clinical diagnosis of drusen and/or retinal pigment epithelial (RPE) changes. In these patients, three patterns of drusen were apparent on UHR-OCT: (1) distinct RPE excrescences, (2) a saw toothed pattern of the RPE, and (3) nodular drusen. On UHR-OCT, three eyes (6%) with a clinical diagnosis of non-exudative AMD had evidence of fluid under the retina or RPE. Two of these three patients had findings suspicious for subclinical choroidal neovascularisation on UHR-OCT. CONCLUSION: With the increased resolution of UHR-OCT compared to standard OCT, the involvement of the outer retinal layers are more clearly defined. UHR-OCT may allow for the detection of early exudative changes not visible clinically or by angiography.

Aged↗
PubMed2001

Activation of a tissue-specific stress response in the aqueous outflow pathway of the eye defines the glaucoma disease phenotype.

The glaucomas are a group of optic neuropathies comprising the leading cause of irreversible blindness worldwide. Elevated intraocular pressure due to a reduction in normal aqueous outflow is a major causal risk factor. We found that endothelial leukocyte adhesion molecule-1 (ELAM-1), the earliest marker for the atherosclerotic plaque in the vasculature, was consistently present on trabecular meshwork (TM) cells in the outflow pathways of eyes with glaucomas of diverse etiology. We determined expression of ELAM-1 to be controlled by activation of an interleukin-1 (IL-1) autocrine feedback loop through transcription factor NF-kappaB, and activity of this signaling pathway was shown to protect TM cells against oxidative stress. These findings characterize a protective stress response specific to the eye's aqueous outflow pathways and provide the first known diagnostic indicator of glaucomatous TM cells. They further indicate that common mechanisms contribute to the pathophysiology of the glaucomas and vascular diseases.

Adolescent↗
PubMed2000

Antiglaucoma medications: a review of safety and tolerability issues related to their use.

BACKGROUND: Much experience has been gained with the use of older classes of antiglaucoma agents--topical beta-adrenergic-receptor antagonists, nonselective adrenergic-receptor agonists, oral carbonic anhydrase inhibitors, and cholinergic agents. In the past decade, new drugs and classes of drugs used to treat glaucoma have become available, including topical carbonic anhydrase inhibitors, prostaglandin analogues, and alpha2-adrenergic-receptor agonists. Extensive community-based use of antiglaucoma medications has led to an increased understanding of the acute and long-term safety and tolerability issues associated with their use. OBJECTIVE: This paper reviews the side effects associated with the various classes of topical antiglaucoma drugs, with a particular focus on long-term safety issues.

Administration, Topical↗
PubMed2000

Effects of systemic beta-blocker therapy on the efficacy and safety of topical brimonidine and timolol. Brimonidine Study Groups 1 and 2.

PURPOSE: To determine the impact of coadminstration of systemic beta-blockers on the ocular hypotensive efficacy and safety of topical timolol, a nonselective, beta-blocker, and that of brimonidine, an alpha2-selective adrenergic agonist, in patients with glaucoma or ocular hypertension. DESIGN: Post hoc evaluation of data collected from two prospective, multicenter, randomized, double-masked, parallel-group, actively-controlled, 12-month clinical trials. PARTICIPANTS: Of the 926 subjects with ocular hypertension or glaucoma that were enrolled in the two prospective trials, 66 (7.1%) were concurrently maintained on systemic beta-blocker therapy. Of these patients, 34 had been assigned to the brimonidine group and 32 to the timolol group. METHODS: Subjects instilled into each eye either 1 drop of brimonidine 0.2% or timolol 0.5% twice daily for 1 year. Study subjects within medication treatment groups were classified as to their use or nonuse of concurrent systemic beta-blockers, and mean intraocular pressure (IOP) reduction, adverse events, heart rate, and blood pressure were compared. MAIN OUTCOME MEASURES: Mean IOP reduction from baseline was the primary efficacy variable. Adverse events and mean changes in heart rate and blood pressure from baseline were the primary safety variables. RESULTS: Timolol-treated subjects concurrently taking systemic beta-blockers had smaller decreases in IOP, a greater mean change in systolic (at week 2, months 1, 2, 6, and 9; P < or = 0.001) and diastolic blood pressure (months 2 and 6; P < or = 0.02), and a significantly greater mean decrease in heart rate (month 6; P = 0.004) compared with timolol subjects not taking systemic beta-blockers. By contrast, there was a modest enhancement of IOP-lowering efficacy at trough and no effect on blood pressure or heart rate in brimonidine-treated subjects who were concurrently receiving systemic beta-blocker therapy compared with brimonidine subjects not receiving systemic beta-blockers. CONCLUSIONS: Concurrent systemic beta-blocker therapy had no deleterious effect on ocular hypotensive efficacy and no impact on systemic safety parameters with topical brimonidine, whereas efficacy was reduced and systemic safety parameters were impacted with topical timolol. Ocular hypotensive agents other than beta-blockers, such as the alpha2 agonist brimonidine, may be a more appropriate first-line therapy for ocular hypertension and glaucoma patients concurrently taking systemic beta-blockers.

Administration, Oral↗
PubMed2000

Increased intraocular pressure and visual field defects in high resistance wind instrument players.

OBJECTIVE: In this twofold study, part 1 aimed to determine whether the playing of high resistance wind instruments elevates intraocular pressure (IOP) and if so, to investigate the mechanism of IOP elevation and whether its magnitude differs while playing high resistance versus low resistance instruments. The purpose of part 2 was to evaluate whether high resistance players have a greater incidence of glaucomatous changes than other musicians. DESIGN: Three case reports and a cross-sectional study. PARTICIPANTS: Two players of high resistance instruments and one player of high and low resistance wind instruments participated in part 1 of the study. Nine high resistance wind players, 12 low resistance wind players, and 24 nonwind players were recruited among professional musicians in the Boston area to participate in part 2. INTERVENTION: In part 1, IOP and uveal thickness changes were measured by pneumatonometry and ultrasound biomicroscopy in two participants playing their high resistance wind instruments (trumpet and oboe) and in a third participant playing both high (trumpet) and low (clarinet and saxaphone) resistance instruments. Each musician in part 2 underwent medical and musical history, measurement of IOP, Humphrey visual field testing, slit-lamp examination, gonioscopy, and dilated examination. MAIN OUTCOME MEASURES: Intraocular pressure and uveal thickness changes, and visual field loss and optic nerve head appearance were the main parameters measured in part 1 and part 2, respectively. RESULTS: In part 1, pneumatonometry showed IOP elevation dependent on the force of blowing, and ultrasound biomicroscopy revealed uveal thickening associated with IOP elevation. The magnitude of IOP elevation was dependent on the amount of expiratory resistance provided by the particular instrument. Part 2 showed that life hours of high resistance wind instrument playing had a significant relationship to abnormal visual field (P = 0.03) and corrected pattern standard deviation (CPSD) scores (P = 0.007) in univariate logistic regression and univariate linear regression, respectively. A 0.011-unit increase in CPSD for each 1000 life hours of high resistance wind playing was found. CONCLUSIONS: High and low resistance wind musicians experience a transient rise in their IOP while playing their instruments as a result least in part of uveal engorgement. The magnitude of IOP increase is greater in high resistance wind players versus low resistance wind players. High resistance wind musicians had a small but significantly greater incidence of visual field loss (abnormal fields and increased CPSD scores) than other musicians, which was related to life hours of playing. The cumulative effects of long-term intermittent IOP elevation during high resistance wind instrument playing may result in glaucomatous damage, which could be misdiagnosed as normal-tension glaucoma.

Aged↗
PubMed1999

A malignant glaucoma-like syndrome following pars plana vitrectomy.

OBJECTIVE: To report two cases of a malignant glaucoma-like syndrome following pars plana vitrectomy. DESIGN: Two interventional case reports. INTERVENTION: The first patient was treated with a neodymium:YAG laser peripheral iridectomy with hyaloidectomy and with intracameral tissue plasminogen activator. The second patient was treated with a posterior approach iridectomy through residual hyaloid, zonules, and iris. MAIN OUTCOME MEASURES: Axial anterior chamber depth and intraocular pressure (IOP). RESULTS: The interventions resulted in deepening of the anterior chambers and normalization of IOPs. CONCLUSION: A pseudomalignant glaucoma syndrome may be related to obstruction of aqueous flow, either by residual anterior hyaloid or by fibrin and other inflammatory debris at the level of the ciliary body-zonular apparatus. Treatment of this syndrome involves restoring aqueous flow to the anterior chamber by disrupting the residual anterior hyaloid or clearing fibrin or inflammatory debris. The clinician should not disregard the possibility of a pseudomalignant glaucoma syndrome following vitrectomy despite the fact that vitrectomy has traditionally been considered a curative treatment for malignant glaucoma.

Aged↗
PubMed1999

Evaluation of focal defects of the nerve fiber layer using optical coherence tomography.

OBJECTIVE: To analyze glaucomatous eyes with known focal defects of the nerve fiber layer (NFL), relating optical coherence tomography (OCT) findings to clinical examination, NFL and stereoscopic optic nerve head (ONH) photography, and Humphrey 24-2 visual fields. DESIGN: Cross-sectional prevalence study. PARTICIPANTS: The authors followed 19 patients in the study group and 14 patients in the control group. INTERVENTION: Imaging with OCT was performed circumferentially around the ONH with a circle diameter of 3.4 mm using an internal fixation technique. One hundred OCT scan points taken within 2.5 seconds were analyzed. MAIN OUTCOME MEASURES: Measurements of NFL thickness using OCT were performed. RESULTS: In most eyes with focal NFL defects, OCTs showed significant thinning of the NFL in areas closely corresponding to focal defects visible on clinical examination, to red-free photographs, and to defects on the Humphrey visual fields. Optical coherence tomography enabled the detection of focal defects in the NFL with a sensitivity of 65% and a specificity of 81%. CONCLUSION: Analysis of NFL thickness in eyes with focal defects showed good structural and functional correlation with clinical parameters. Optical coherence tomography contributes to the identification of focal defects in the NFL that occur in early stages of glaucoma.

Cross-Sectional Studies↗
PubMed1999

Sialyl Lewis X, Lewis X, and N-acetyllactosamine expression on normal and glaucomatous eyes.

PURPOSE: Sialyl Lewis X (sLex), Lewis X (Lex), and N-acetyllactosamine are carbohydrate chains of neolactoglycoconjugates which are expressed by specific cell types and are important in the functioning of cells within an organism. This study attempts to determine the expression of these glycoconjugates on the conjunctiva, cornea, and trabecular meshwork (TM) of both normal and glaucomatous eyes. METHODS: Frozen anterior segment sections of both normal and glaucomatous human cadaver eyes, as well as rabbit eyes, were stained with a panel of monoclonal antibodies (mAbs) to neolactoglycoconjugates using an Avidin Biotin Peroxidase Complex/Alkaline Phosphatase staining method. RESULTS: SLex characteristically stained both human conjunctival and corneal epithelia in normal (n=5) and glaucomatous (n=5) sections. SLex stained corneal and conjunctival epithelia of glaucomatous eyes much more intensely than normal eyes. Rabbit cornea sections stained for sLex, Lex, and N-acetyllactosamine. However, human cornea only consistently stained with sLex. Normal and glaucomatous human TM sections did not stain for sLex, Lex, or N-acetyllactosamine. CONCLUSIONS: The expression of glycoconjugates with sLex side chains appears to be upregulated in the conjunctival and corneal epithelia of glaucomatous eyes. Distinct species specific differences were noted in Lex and N-acetyllactosamine staining patterns in rabbit and human corneal epithelia.

Aged↗
PubMed1999

Excimer laser effects on outflow facility and outflow pathway morphology.

PURPOSE: To determine the relative contributions to aqueous outflow resistance of the tissues distal to the inner wall of Schlemm's canal. METHODS: While performing constant pressure perfusion at 10 mm Hg, a 193-nm excimer laser (Questek) was used to precisely remove portions of sclera, unroofing Schlemm's canal while leaving the inner wall intact. The laser beam was masked to produce a beam 2 mm by 1 mm. The laser output was constant at a fluency of 75 mJ/cm2 and 20 Hz. The excimer laser at a frequency of 1 Hz was used as the aiming beam. Photoablation was performed on human cadaver eyes at the limbus at an angle of 0 degrees to 45 degrees from the optical axis. As the excimer photoablations progressed, Schlemm's canal was visualized by the fluorescence of the Barany's solution containing fluorescein dye. After perfusion fixation the eyes were immersion-fixed overnight. The facility of outflow before (Co) and after (Ce) the excimer ablation was measured in 7 eyes. RESULTS: The facility of outflow increased in all eyes after the excimer sinusotomy, from a mean of 0.29+/-0.02 before the sinusotomy to 0.37+/-0.03 microl/min per mm Hg after (P < 0.05). The mean ratio of outflow facility after and before ablation (Ce/Co) was 1.27+/-0.08 (range, 1.20-1.39), a reduction of outflow resistance of 21.3%. Using the formula of Ellingsen and Grant (1972), percentage of resistance to outflow eliminated = 100 [1 - alphaCo/Ce - (1 - alpha)Co], where alpha = fraction of the circumference dissected. Assuming that because of circumferential flow approximately 50% of Schlemm's canal is drained by the single opening made in the outer wall ablation studies, this results in resistance to outflow eliminated of 35%, which is consistent with the calculated eliminated resistance derived from the data of Rosenquist et al., 1989. Light and scanning electron microscopy confirmed the integrity of the inner wall Schlemm's canal underlying the area of ablation. CONCLUSIONS: The results provide direct evidence indicating that approximately one third of resistance to outflow in the human eye lies distal to the inner wall Schlemm's canal in an enucleated perfused human eye.

Anterior Chamber↗
PubMed1998

Five-year results of a randomized, prospective, clinical trial of diode vs argon laser trabeculoplasty for open-angle glaucoma.

PURPOSE: To evaluate the safety and efficacy of laser trabeculoplasty (LTP) with a semiconductor diode laser (810 nm, [DLT]) vs an argon blue-green laser (488 to 514 nm, [ALT]). METHODS: In a prospective, randomized clinical trial, 50 eyes of 46 patients with uncontrolled open-angle glaucoma on maximally tolerated medical therapy were treated and followed at regular intervals for 5 years. Fifty laser spots were applied over 180 degrees using either maximal laser power or sufficient power to produce blanching or a small bubble (570 to 850 mW, DLT; 400 to 1,100 mW, ALT). We performed DLT using a 100-microm spot size, a 0.5-second exposure, and a Ritch lens; we conducted ALT with a 50-microm spot, a 0.1-second exposure, and a Goldmann lens. Patients in the study were followed until trabeculectomy was required. RESULTS: The mean follow-up times +/- SD for all eyes were 38.6 +/- 5.4 months, DLT (n = 22; range, 1 to 68 months) and 35.5 +/- 4.8 months, ALT (n = 28; range, 1 to 66 months). Those in the diode laser group (n = 16) who had more than 1 year of follow-up were tracked for 49.4 months, and those in the argon laser group (n = 21) were tracked for 45.8 months. There were no significant differences in the mean pretreatment intraocular pressures (IOPs): 21.2 mm Hg, DLT (n = 22) and 21.5, ALT 21.5 mm Hg (n = 28); P = .81] or in mean final IOPs (15.7 mm Hg, DLT and 17.1 mm Hg, ALT; P = .19). Time to surgical failure showed no significant differences, with 50% of the DLT eyes and 58% of the ALT eyes surviving at 5 years (P = .59). CONCLUSION: In eyes with open-angle glaucoma and unsatisfactory IOP control on maximally tolerated medical therapy, DLT and ALT are equally effective in lowering IOP over a 5-year period.

Aged↗
PubMed1998

Topography of diabetic macular edema with optical coherence tomography.

OBJECTIVE: This study aimed to develop a protocol to screen and monitor patients with diabetic macular thickening using optical coherence tomography (OCT), a technique for high-resolution cross-sectional imaging of the retina. DESIGN: A cross-sectional pilot study was conducted. PARTICIPANTS: A total of 182 eyes of 107 patients with diabetic retinopathy, 55 eyes from 31 patients with diabetes but no ophthalmoscopic evidence of retinopathy, and 73 eyes from 41 healthy volunteers were studied. INTERVENTION: Six optical coherence tomograms were obtained in a radial spoke pattern centered on the fovea. Retinal thickness was computed automatically from each tomogram at a total of 600 locations throughout the macula. Macular thickness was displayed geographically as a false-color topographic map and was reported numerically as averages in each of nine regions. MAIN OUTCOME MEASURES: Correlation of OCT with slit-lamp biomicroscopy, fluorescein angiography, and visual acuity was measured. RESULTS: Optical coherence tomography was able to quantify the development and resolution of both foveal and extrafoveal macular thickening. The mean +/- standard deviation foveal thickness was 174 +/- 18 microns in normal eyes, 179 +/- 17 microns in diabetic eyes without retinopathy, and 256 +/- 114 microns in eyes with nonproliferative diabetic retinopathy. Foveal thickness was highly correlated among left and right eyes of normal eyes (mean +/- standard deviation difference of 6 +/- 9 microns). Foveal thickness measured by OCT correlated with visual acuity (r2 = 0.79). A single diabetic eye with no slit-lamp evidence of retinopathy showed abnormal foveal thickening on OCT. CONCLUSIONS: Optical coherence tomography was a useful technique for quantifying macular thickness in patients with diabetic macular edema. The topographic mapping protocol provided geographic information on macular thickness that was intuitive and objective.

Adult↗
PubMed1998

Effect of optic nerve head drusen on nerve fiber layer thickness.

OBJECTIVE: The purpose of the study was to evaluate the effect of optic nerve head drusen (ONHD) on nerve fiber layer (NFL) thickness by visual field testing, red-free photography of NFL, and optical coherence tomography (OCT). DESIGN: The study design was a prospective clinical study. PARTICIPANTS: Twenty-three eyes of 15 consecutive patients with ONHD and 27 eyes of 27 age-matched control subjects participated. INTERVENTION: Ophthalmologic examination, color and red-free photography, automated Humphrey visual field testing, and OCT were performed. Each of the drusen study eyes were graded on a scale of 0 to III based on the amount of visible ONHD. Grade 0 represented the absence of clinically visible ONHD, and grade III represented an optic nerve head with abundant drusen. MAIN OUTCOME MEASURES: Findings from clinical evaluation and color optic nerve head photographs and NFL evaluation by red-free photography, visual fields, and OCT were measured. RESULTS: The number of study eyes with visual field defects increased with the higher grade drusen discs, corresponding both with progressively thinner NFL measurements by OCT and NFL loss shown by NFL photography. The NFL evaluation showed NFL thinning by red-free photography in 12 (71%) of 17 eyes with visible drusen (grades I-III discs) and visual field defects in 9 (53%) of 17 eyes in this group. By OCT measurements, the superior and inferior NFLs were significantly thinner in the eyes with visible ONHD compared with those of control eyes in the superior quadrant (P < 0.001) and inferior quadrant (P = 0.004). Compared with grade 0 discs, grades I through III discs showed statistically significant thinning of the NFL superiorly (P < 0.001). No statistical significant thinning of the NFL was seen in grade 0 discs compared with those of control subjects. CONCLUSIONS: Optical coherence tomography is able to detect NFL thinning in eyes with ONHD and appears to be a sensitive and early indicator of NFL thinning. Increased numbers of clinically visible ONHD correlated with NFL thinning shown by OCT measurements and both visual field defects and NFL loss seen by red-free photography.

Female↗
PubMed1998

Tonometry in adults and children. A manometric evaluation of pneumatonometry, applanation, and TonoPen in vitro and in vivo.

OBJECTIVE: The purpose of the study was to determine the accuracy of applanation tonometry, pneumatonometry, and TonoPen tonometry in adults and children and the effect of age on tonometer error. DESIGN: The design was divided into four parts: part 1 was prospective and cross-sectional, and parts 2 through 4 were prospective, cross-sectional, and masked. PARTICIPANTS: This study contained 72 patients representing 74 data points. INTERVENTION: Tonometry with simultaneous manometry was performed. MAIN OUTCOME MEASURES: Intraocular pressure (i.o.p.) and the tonometric estimate of IOP were obtained. RESULTS: The normal pediatric IOP follows the line Ta = 0.71 age(years) + 10 up to age 10. Applanation tonometry under anesthesia differs from pneumatonometry by an average of -8.6 mmHg and is age related by the equation Ta = Tpn + 2.6 log(age) - 10.3. The TonoPen was the most accurate instrument for enucleated eyes, and the pneumatonometer was the most accurate in anesthetized living eyes. CONCLUSIONS: Applanation tonometry markedly underestimated IOP in young eyes. TonoPen tonometry performed well with enucleated eyes but was not adequately accurate for clinical use. The pneumatonometer performed the best clinically and the best overall.

Adolescent↗
PubMed1998

Comparison of mitomycin C trabeculectomy, glaucoma drainage device implantation, and laser neodymium:YAG cyclophotocoagulation in the management of intractable glaucoma after penetrating keratoplasty.

PURPOSE: This study aimed to compare the surgical outcomes of mitomycin C trabeculectomy glaucoma drainage device (GDD) surgery and laser neodymium:YAG (Nd:YAG) cyclophotocoagulation (CPC) in the management of intractable glaucoma after penetrating keratoplasty (PKP) in a retrospective study. DESIGN: Interventional case series. PARTICIPANTS/METHODS: The medical charts of consecutive patients who had pre-existing glaucoma or who developed glaucoma after PKP and underwent a surgical procedure to control the glaucoma at the University Eye Associates of Boston University Medical Center, New England Eye Center, and Massachusetts Eye and Ear Infirmary between January 1991 and July 1995 were reviewed. Follow-up ranged from 6 months to 4 years after the glaucoma procedure. A total of 38 patients were included consisting of 17 patients who underwent mitomycin C, 10 patients who underwent GDD surgery, and 11 patients who had CPC. INTERVENTION: Mitomycin C trabeculectomy, GDDs, or Nd:YAG CPC to control glaucoma after PKP was performed, MAIN OUTCOME MEASURES: Graft status, postoperative intraocular pressure (IOP), and visual acuity were the main outcome measures. RESULTS: There were no differences among the three groups with respect to the follow-up time after the corneal graft operation (P = 0.15) or after the glaucoma operation (P = 0.98). At the final follow-up, the average decrease in the IOP was 17 mmHg (P < 0.001) after mitomycin C, 15 mmHg (P = 0.003) after GDD surgery, and 14.4 mmHg (P = 0.001) after CPC. There were no differences in the proportion of patients who developed postoperative IOP above 20 mmHg (P = 0.50) and in the proportion who developed hypotony (P = 0.10) among the three groups. Two grafts failed after mitomycin C and one failed after CPC. Among the three procedures, there were no differences in the proportion of patients who experienced either an improvement (P = 0.14) or a decrease (P = 0.22) in the visual acuity by more than one line after the glaucoma procedure. One patient each in the GDD group and the CPC group lost light perception after the procedure. The risk of graft failure was almost three times higher for each additional PKP (odds ratio = 2.80, P = 0.02). CONCLUSIONS: No differences were found among the three glaucoma procedures with respect to controlling IOP and graft failure. There was a trend for patients treated with CPC to have a higher incidence of graft failure, glaucoma failure, hypotony, and visual loss by more than one line, although this was not statistically significant. The number of PKPs was associated with graft failure, independent of the surgical procedure.

Adolescent↗