Dorothy G. Cooper

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.

Assessing the Utility of Reliability Indices for Automated Visual Fields: Testing Ocular Hypertensives

Monocular (right eye) visual fields were recorded with the Humphrey Visual Field Analyzer (30-2 Program) at baseline as well as 6 and 12 months later in 120 patients with established ocular hypertension. Indices of field reliability (fixation loss, less than 20%; false-positives and false-negatives, less than 33%) and field sensitivity (mean deviation [MD] and pattern standard deviation [PSD]) were examined. At baseline, 35% of patients exhibited low reliability (LR) fields, a figure which decreased to approximately 25% at 6 and 12 months, respectively. During this period, over 50% of patients produced at least one LR field, whereas 8.3% were unable to produce even one reliable field. Exhibition of a LR field appeared to be independent of patient age. Fixation errors, the major cause of LR fields, decreased by approximately 10% over the 12-month period; most patients had between 20 and 32% fixation errors. The incidence of significant defects identified by PSD was greater than that for MD; this was true for both reliable and LR fields. It is suggested that increasing the fixation loss criteria for assessing patient reliability to a 33% cutoff might substantially increase the percentage of fields graded reliable with minimal effect on the sensitivity or specificity of the test.

The Pigment Dispersion Syndrome

The pigment dispersion syndrome was noted in 10% of white and black subjects with and without glaucoma. This suggested pigment dispersion was not a high risk factor in the development of glaucoma. The HLA-B7 antigen was less prevalent and HLA-B13 and Bw17 antigens were significantly more prevalent in individuals with the pigment dispersion syndrome than in subjects without the syndrome. Either HLA-B13 or Bw17 antigen was found in 23 (77%) of 30 patients with the pigment dispersion syndrome and in only 13 (6%) of the 203 subjects without pigment dispersion. Pigmentary glaucoma was characterized by a significantly higher prevalence of combinations of HLA-B12 and B13 or HLA-B12 and Bw17 antigens as compared to the pigment dispersion syndrome without glaucoma, primary open-angle glaucoma, or the general population. This suggested that pigmentary glaucoma differed genetically from primary open-angle glaucoma and was a separate entity.

Pattern reversal electroretinogram (PRERG) abnormalities in ocular hypertension: correlation with glaucoma risk factors

The indices employed commonly for the diagnosis of glaucoma (tonometry, ophthalmoscopy and perimetry) do not always identify which patients with ocular hypertension (OHT) will develop primary open-angle glaucoma (POAG) before irreversible visual field loss is manifest (1). The human pattern reversal electroretinogram (PRERG) is a bioelectric response reflecting neural activity of the proximal retina. PRERG amplitude reductions have been observed in POAG and other diseases affecting the optic nerve and retinal ganglion cells. This study was designed to determine whether OHT patients exhibit PRERG amplitude reductions and whether PRERG results are correlated with routinely evaluated clinical parameters. Steady-state PRERG (16 rps) were elicited by high contrast (76%), phase alternating checkerboard patterns (15-20 min checks) from one eye of 130 patients with ocular hypertension and 47 age matched visual normals (AMVNs). A significant (p less than 0.05) reduction in PRERG amplitude was noted for the OHT patients and 11.5% of those patients exhibited PRERG amplitudes more than 2.0 standard deviations below the AMVN mean. PRERG amplitude was found to be positively correlated with diastolic blood pressure (DBP) and negatively correlated with age, but no correlation between PRERG amplitude and either IOP, C/D ratio, or systolic blood pressure was evident. The lack of correlation between PRERG amplitude and the commonly used clinical indices may suggest a complementary role for this neurophysiologic test in determining which OHT patients will develop glaucoma.

The human pattern ERG : alteration of response properties with aging

The influence of aging on both the amplitude and the latency of transient and steady-state pattern electroretinograms (PERGs) was studied in 80 healthy participants ranging from 25 to 77 years of age (mean age, 55.3 years). Responses to counterphasing checkerboard patterns were recorded for each of 7 test conditions in which the spatial (i.e., check sizes 0.25, 0.50, 1.00, and 2.00 degrees) and temporal characteristics (i.e., counterphasing at either 2, 4, 8, or 16 rps) of the stimuli were varied. For both the transient and steady-state PERGs amplitude was inversely related to age (p less than 0.05 for each test condition). In general, PERG latency directly correlated with age, but this effect was less robust (p less than 0.05 for one transient condition and three of the four steady-state conditions). The influence of age on the spatial tuning of the PERG was minimal; the decrease in PERG amplitude and the increase in PERG latency as a function of age were essentially the same for all test conditions. However, the magnitude of the age-related reduction in PERG amplitude was observed to vary with temporal frequency, being largest for the steady-state condition (16 rps). The results from an experiment in which young subjects were tested while wearing opaque contact lenses with 2-mm artificial pupils suggest that senile miosis is a significant factor contributing to the age-related PERG amplitude and latency changes, but it does not fully account for the observed changes.

Lack of Correlation Between Ocular Hypertensive Response to Topical Corticosteroids and Progression of Retinopathy in Insulin-Dependent Diabetes Mellitus

We studied the relationship of intraocular pressure responsiveness to topical corticosteroids and the development of retinopathy in 86 patients with insulin-dependent juvenile-onset diabetes available for long-term follow-up and examination during 1982. Eleven patients had background retinopathy at the initial examinations. High (GG) and intermediate (NG) corticosteroid responsiveness was more common in these 86 patients (13 high responders and 39 intermediate responders) than in previously reported volunteer series. Background diabetic retinopathy was present at the end of the study in 75 of the 86 patients and proliferative retinopathy was present in 29. The proportions of patients developing either type of retinopathy were similar among the low (NN), intermediate, and high response groups. The rate of diabetic retinopathy development was related to the duration of the disease and not to the intraocular pressure response to topical corticosteroids.