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Biomedical subjects

M A Kass

Publications and source records attributed to M A Kass.

At least 37 records · Page 2Linked to original sources
PubMed1993

Follow-up of angle-closure glaucoma suspects.

One hundred twenty-nine patients thought to be at risk for developing angle-closure glaucoma underwent a baseline examination, which included gonioscopy, refraction, anterior chamber pachymetry, ultrasound biometry, and an angle-closure provocative test. Patients were then followed up with no treatment. Mean follow-up was 2.7 years with a range up to six years. Twenty-five patients developed angle closure in at least one eye during the follow-up period, but in most (17 of the 25 patients), the angle closure was nonacute (that is, no clinical signs or symptoms and no increase in intraocular pressure). None of the test factors studied showed a high sensitivity or positive predictive accuracy in detecting the eyes that later developed angle closure.

Adult↗
PubMed1993

Trabeculectomy with releasable sutures.

We attempted to reduce some of the postoperative complications of trabeculectomy by using releasable scleral flap sutures. This technique allows an initial tight closure of the scleral flap with the option to increase aqueous humor outflow in the early postoperative period. We reviewed our experience with trabeculectomy and releasable sutures in 146 eyes (134 patients) and compared these cases with a prior series of 128 eyes (124 patients) that underwent trabeculectomy with permanent scleral flap sutures. In the control group, 42 eyes (32.8%) had clinically detectable shallowing of the anterior chamber in the postoperative period. In contrast, shallow anterior chamber was noted in 21 eyes (14.4%) in the group with releasable sutures (P = .0003). Flat anterior chamber, defined as iridocorneal touch to the pupil margin, occurred in 11 control eyes (8.6%) but in only 2 eyes (1.4%) with releasable sutures (P = .0078). Surgical intervention to drain suprachoroidal fluid and re-form the anterior chamber was required in eight control eyes (6.2%) but in only one study eye (0.7%) (P = .014). At 1 year of follow-up, the two groups were similar in terms of mean intraocular pressure, the need for ocular hypotensive medications, and failure rate.

Aged↗
PubMed1992

Gonioscopic ab interno laser sclerostomy. A pilot study in glaucoma patients.

PURPOSE: The purpose of this study is to evaluate the safety and efficacy of gonioscopic ab interno laser sclerostomy (GLS) in patients with glaucoma. METHODS: The technique of GLS involves iontophoresis of methylene blue dye (1%) at the limbus to focally dye the sclera and to provide subsequent delivery of 10-microsecond pulsed laser energy to the dyed area through a goniolens. The laser emits at 660 nm, a wavelength that is maximally absorbed by the methylene blue dye. Patients were evaluated for fistula formation, intraocular pressure (IOP) reduction, and adverse sequelae. Thirty-eight treatments were performed in 35 eyes. RESULTS: Successful complete sclerostomies were achieved in 21 eyes (55%), which was associated with an acute mean reduction in IOP of 23 mmHg. Mean preoperative IOP for all patients was 35 mmHg, and 1 hour after treatment it was reduced to 18.5 mmHg. In 4 of the 38 treatments, there was no acute IOP reduction, and these eyes were judged as failures. The mean follow-up time was 8.2 months with a maximum follow-up of 15 months. By 9 months, 50% of patients had an IOP of 22 mmHg or lower. The number of antiglaucoma medications decreased from 3.1 to 1.7 for all eyes over the 15-month follow-up period. Hyphemas (13%) were the only major complication, and these resolved spontaneously. In only one case did the IOP increase after the procedure. CONCLUSION: The results of this trial indicate that GLS is technically feasible, and preliminary results of IOP control are promising.

Adult↗
PubMed1991

MK-507 versus sezolamide. Comparative efficacy of two topically active carbonic anhydrase inhibitors.

Topical carbonic anhydrase inhibitors MK-507 and sezolamide hydrochloride (previously known as MK-417) were compared in a double-masked, randomized, placebo-controlled study in 82 patients with bilateral primary open-angle glaucoma or ocular hypertension. MK-507 was given every 8 or 12 hours, sezolamide every 8 hours, or placebo every 8 or 12 hours for 4 days. Both drugs lowered intraocular pressure (IOP) substantially. MK-507 was somewhat more active than sezolamide, with a peak mean IOP reduction of 26.2% for MK-507 versus 22.5% for sezolamide, although the difference between the treatments was not statistically significant. These drugs may have potential in the treatment of glaucoma.

Administration, Topical↗
PubMed1990

MK-927: a topical carbonic anhydrase inhibitor. Dose response and duration of action.

The dose response to a single topical administration of the carbonic anhydrase inhibitor MK-927 was investigated in 24 patients with primary open angle glaucoma or ocular hypertension. Three concentrations of MK-927 (2%, 1%, and 0.5%) and placebo were administered in a two-center, double-masked, randomized, placebo-controlled, four-period crossover study. MK-927 at the 0.5% concentration appeared to be minimally effective in reducing intraocular pressure. A single topical dose of 1% MK-927 resulted in a significantly greater percent reduction in intraocular pressure for up to 6 hours when compared with treatment with placebo. Similarly, a single dose of 2% MK-927 significantly lowered intraocular pressure for 8 hours compared with treatment with placebo. The pressure reduction from baseline measured 23.7% and 11.3% at 8 hours after instillation of a single drop of 2% MK-927. The medication was well tolerated and appeared to lower intraocular pressure in a dose-dependent fashion.

Adult↗
PubMed1990

Steady-state pattern electroretinogram following long term unilateral administration of timolol to ocular hypertensive subjects.

To determine whether long-term reduction of intraocular pressure leads to a corresponding preservation of the pattern electroretinogram (PERG), PERGs were studied in 21 patients with ocular hypertension who had received unilateral timolol therapy for a minimum of 6 years. The mean difference in intraocular pressure (IOP) between the placebo-treated and the timolol-treated eyes (over 6 years) was 2.4 mm Hg. Steady-state PERGs (16.0 rps) were obtained simultaneously in both eyes of each patient, with four check sizes (0.25, 0.5, 1.0 and 2.0 degrees). Significant (p less than 0.05) steady-state PERG deficits (i.e., amplitude more than two standard deviations below the mean value of age-matched controls) were observed in 16 eyes of 12 patients (10 placebo-treated and 6 timolol-treated eyes). The mean PERG amplitude did not differ significantly between the placebo-treated and timolol-treated eyes. However, a significant correlation (r = -0.423) in the IOP differences between the placebo-treated and timolol-treated eyes and the corresponding PERG amplitude differences was noted in three of the four test conditions (i.e. 0.25, 0.5, and 1.0 degrees). These results suggest that reducing IOP may preserve ganglion cell function in some patients with ocular hypertension.

Aged↗
PubMed1990

Transscleral neodymium: YAG laser cyclocoagulation for uncontrolled glaucoma.

To determine the efficacy and safety of the procedure, we reviewed the records of 25 eyes of 25 patients who had received noncontact transscleral Nd:YAG laser cyclocoagulation for a variety of uncontrolled glaucomas. Thirteen to 35 pulses (mean, 22.7 pulses) had been placed 1 mm to 2 mm behind the limbus with an energy per pulse of 3.4 J to 8.2 J (mean 4.5 J). Follow-up ranged from 6 months to 23 months, with the exception of one eye, which had to be enucleated. Nine of the 25 eyes (36%) required one or two repeat treatments. Twelve (48%) had intraocular pressures at last follow-up of less than 21 mm Hg but greater than 4 mm Hg. Ten eyes (40%) developed moderate to severe pain transiently, and 10 (40%) developed substantial, but transient, inflammation. Transscleral Nd:YAG laser cyclocoagulation appears to be relatively effective and well tolerated.

Adolescent↗
PubMed1989

Topical timolol administration reduces the incidence of glaucomatous damage in ocular hypertensive individuals. A randomized, double-masked, long-term clinical trial.

We conducted a randomized, double-masked, long-term clinical trial to determine whether topical timolol therapy was effective in delaying or preventing the onset of glaucomatous damage in moderate-risk ocular hypertensive subjects. In 62 patients, one eye was chosen randomly to receive timolol therapy twice daily while the fellow eye received placebo. During the course of the study, the mean +/- SD difference in intraocular pressure between the timolol-treated and the placebo-treated eyes was 2.3 +/- 2.6 mm Hg. Reproducible visual field loss developed in 4 timolol-treated eyes and 10 placebo-treated eyes. Progressive optic disc cupping was noted in 4 timolol-treated and 8 placebo-treated eyes. Using a computerized image analysis system, the mean +/- SD increase in optic disc pallor during the course of the study was 0.86% +/- 2.4% in the timolol-treated eyes as opposed to 1.80% +/- 3.6% in the placebo-treated eyes. This study provides evidence that lowering intraocular pressure by medical treatment reduces the incidence of glaucomatous damage in ocular-hypertensive individuals.

Administration, Topical↗
PubMed1989

Timolol treatment prevents or delays glaucomatous visual field loss in individuals with ocular hypertension: a five-year, randomized, double-masked, clinical trial.

A 5-year, randomized, double-masked, clinical trial was conducted to determine whether treatment with topical timolol maleate was effective in preventing or delaying the onset of glaucomatous visual field loss in subjects with ocular hypertension. Sixty-five individuals considered to be at moderate risk for developing open-angle glaucoma were recruited for the study. In each patient, one eye was chosen randomly to receive timolol twice-daily while the fellow eye received diluent (placebo). Timolol administration reduced IOP from baseline in the treated eyes over the course of the study by a mean +/- SD of 4.9 +/- 3.4 mm Hg. Timolol administration also produced a mean +/- SD contralateral reduction of IOP from baseline in the untreated fellow eyes of 2.9 +/- 3.1 mm Hg. The mean +/- SD difference in IOP between the treated and untreated eyes during the study was 2.3 +/- 2.6 mm Hg. Over the course of the study reproducible visual field loss developed in 4 timolol treated eyes and 10 placebo treated eyes (P = .039, McNemar test). Clinical progressive optic disc cupping was noted in four treated and eight untreated eyes (P = .11, McNemar test). In the 42 subjects who completed a minimum 4-year follow-up, baseline and final optic disc photographs were analyzed using a computer image analysis system to determine changes in the area of disc pallor. The mean +/- SD increase in optic disc pallor was 0.86% +/- 2.4% in the timolol treated eyes and 1.80% +/- 3.6% in the placebo treated eyes. This difference was statistically significant (P = .04, paired t-test). This study provides evidence that medical treatment prevents or delays the onset of glaucomatous visual field loss and optic disc damage in individuals with ocular hypertension. The magnitude of the protective effect of timolol was partially obscured by the contralateral reduction of IOP in the placebo treated fellow eyes.

Adult↗
PubMed1988

Intraocular pressure response to topical dexamethasone as a predictor for the development of primary open-angle glaucoma.

In a retrospective study we reviewed the records of 788 subjects who had been corticosteroid tested with 0.1% dexamethasone four times daily to one eye for six weeks. All subjects had normal kinetic visual fields and optic nerve heads in both eyes at the time of testing and were followed up for a minimum of five years. Some subjects had normal baseline intraocular pressures whereas others were considered to have ocular hypertension. Of 276 individuals who were high corticosteroid responders (intraocular pressure greater than 31 mm Hg during dexamethasone administration), 36 (13.0%) developed glaucomatous visual field loss during the follow-up period. Only nine of 261 individuals (3.4%) who were intermediate responders (intraocular pressure 20 to 31 mm Hg during dexamethasone administration) and none of 251 individuals who were low responders (intraocular pressure less than 20 mm Hg during dexamethasone administration) developed glaucomatous visual field loss. However, the ability of the intraocular pressure response to dexamethasone to predict the development of glaucomatous visual field loss was not as good as the predictive power of a multivariate model that included patient age, race, baseline intraocular pressure, baseline outflow facility, baseline cup/disk ratio, and systemic hypertension.

Adult↗
PubMed1987

Compliance with topical timolol treatment.

To determine if compliance with timolol treatment was better than compliance with pilocarpine treatment (as reported previously), we measured compliance with timolol treatment in a sample of 110 patients using an unobtrusive eyedrop medication monitor, which recorded electronically the date and time of each drug administration over a four- to six-week period. The patients administered a mean +/- S.D. of 82.7% +/- 19.0% of the prescribed timolol doses (range, 20% to 100%). Forty-five patients were treated concurrently with timolol and pilocarpine. These patients administered a mean +/- S.D. of 84.3% +/- 14.0% of the prescribed timolol doses and 77.7% +/- 18.7% of the prescribed pilocarpine doses (P = .012, van der Waerden test). Our results suggest that while compliance is influenced by the drug regimen, defaulting is not eliminated by prescribing a more convenient medication with fewer side effects.

Adolescent↗
PubMed1986

Compliance with topical pilocarpine treatment.

Using an unobtrusive eyedrop medication monitor, we measured compliance with topical pilocarpine treatment in a sample of 184 patients. The eyedrop monitor recorded electronically the date and time of each pilocarpine administration over a four- to six-week period. The subjects administered a mean +/- S.D. of 76.0% +/- 24.3% of the prescribed pilocarpine doses. Eleven patients (6%) took less than one quarter and 28 patients (15.2%) took less than one half of the prescribed administrations. In contrast, when the subjects were interviewed they reported taking a mean +/- S.D. of 97.1% +/- 5.9% of the prescribed pilocarpine doses. As determined by the monitor, 45 patients (24.5%) had at least one day per month with no administrations of pilocarpine; 56 subjects (30.4%) compressed the doses during the daytime hours, leaving an interval between the night dose and the morning dose the next day of 12 hours or more. The rate of compliance was significantly higher (P less than .0001) in the 24-hour period preceding the return appointment than in the entire observation period.

Aged↗
PubMed1986

Can ophthalmologists correctly identify patients defaulting from pilocarpine therapy?

We determined whether clinical measurements and assessments available to ophthalmologists could be used to identify patients who default from pilocarpine treatment. The measurements and assessments included intraocular pressure, pupillary diameter, pupillary reactivity to light, the patient's report of compliance, the physician's prediction of compliance, the patient's log of pilocarpine administration, and the weight of pilocarpine eyedrops utilized. Compliance with the pilocarpine regimen was measured with an unobtrusive eyedrop medication monitor. Intraocular pressure and pupillary diameter did not correlate with compliance to the regimen as measured by the eyedrop monitor. Pupillary reaction to light, the physician's prediction of compliance, a daily log of pilocarpine administration, the weight of pilocarpine utilized, and the patient's report of compliance correlated modestly with compliance as measured by the monitor (range of correlations, 0.19 to 0.24). However, none of these measures taken by itself or combined in any manner adequately distinguished patients with lower rates of compliance from those with higher rates of compliance. At present, the eyedrop monitor is the only reliable method for detecting patients who default from treatment.

Glaucoma↗