PubMed HealthSearch

Biomedical subjects

H H Hunt

Publications and source records attributed to H H Hunt.

10 recordsLinked to original sources

Pattern discrimination perimetry in patients with glaucoma and ocular hypertension.

We compared the results of the pattern discrimination perimeter to the program 30-2 on the Humphrey Field Analyzer (Humphrey, Inc., San Leandro, California) in 93 consecutive patients with ocular hypertension and glaucoma and 30 control patients. In 20 patients with ocular hypertension, a significantly greater number of glaucomatous defects were noted on pattern discrimination perimetry (ten patients) than on the program 30-2 (two patients) (P less than .05, Wilcoxon signed rank test). The diversity in diagnoses found on pattern discrimination testing was not explained by age, intraocular pressure, refraction, number of glaucoma medicines, race, presence of vascular disease, optic disk status, or pupil size. In contrast, in 73 patients with glaucoma no statistical difference in the severity of diagnoses was noted between perimeters (P greater than .05, Wilcoxon signed rank test). These results suggest the potential value of pattern discrimination perimetry as a visual function test in patients with glaucoma and in defining subsets of patients with ocular hypertension not found with conventional automated perimetry.

Adult

Long-term and short-term fluctuation in pattern discrimination perimetry.

We studied threshold fluctuation with the pattern discrimination perimeter in 24 healthy subjects at 56 locations within the central 30 degrees. This perimeter evaluates a subject's ability to discriminate a patterned stimulus measured by a percentage scale. We found an intraindividual fluctuation of 10.52% and an interindividual fluctuation of 8.78%. A statistically increased intraindividual, but not interindividual fluctuation was noted with increasing eccentricity from fixation (P less than .05, Bartlett's test). However, no correlation in fluctuation was noted with advancing age or increasing false-positive errors (P greater than .05, correlation coefficient). Also, no difference in fluctuation between superior or inferior hemifields was observed (P greater than .05, Student's t-test). The average threshold across all subjects was 54.3%, which provided an upper limit of normal, two standard deviations from the mean, of less than 80% for most locations. This study indicates that fluctuation should be considered when interpreting pattern discrimination fields, but that the extent of fluctuation generally allows for an adequate separation between normal and abnormal measurements.

Adult

The effect of stimulus duration upon the components of fluctuation in static automated perimetry.

We studied the effect of varying the stimulus duration time on the components of fluctuation in static automated perimetry by testing 20 healthy subjects on the Humphrey Field Analyser within the central 20 degrees of vision. We found the total fluctuation at a stimulus duration of 0.065 s, to be 3.22 decibels (dB); 0.1 s, 3.22 dB; 0.2 s, 3.34 dB; 0.3 s, 2.95 dB; 0.4 s, 3.24 dB; and 0.5 s, 3.22 dB. Little difference was observed in the individual components (short-term, long-term homogeneous, long-term heterogeneous and inter-individual) or total fluctuation with an increasing stimulus presentation time when evaluated over the entire visual field or in a pointwise fashion. This study suggests that the stimulus duration within the range of times studied has little effect on the components or total fluctuation in healthy individuals.

Adolescent

Association of reliability with reproducibility of the glaucomatous visual field.

We studied 207 glaucoma patients (207 eyes) who had two successive visual tests on the Humphrey Field Analyzer to determine the association of unreliability (> 10% incidence of a missed catch trial test) with threshold variation. We found that in patients where one visual field showed > 30% false negative or positive errors, and the other visual field also was unreliable, a significant increase in the variance of the mean defect existed from reliable patients (p < 0.05). Of patients who had only one of two visual fields which was unreliable (from false negative errors), only those with marked glaucomatous visual field loss (< -15 dB depth of defect) showed a greater variance in mean defect between examinations over reliable patients (p < 0.05). In total, 41 patients (19.8%) had unreliable visual fields associated with statistically increased threshold variation. This study suggests that patient reliability should be considered when interpreting changes in threshold between automated visual field examinations.

Aged

Histologic differences in the conjunctiva of black and white glaucoma patients.

We compared perioperative conjunctival biopsy specimens from 31 consecutive trabeculectomy patients to determine if there were any histologic differences between black and white glaucoma patients. We found a statistically significantly greater mean and distribution of mast cells and neutrophils in the white patients. No significant difference was found in the mean number of goblet cells, eosinophiles, macrophages, fibroblasts, plasma cells, or lymphocytes; or in thickness of the epithelium, vascular density, or collagen or mucopolysaccharide staining. We conclude that histological conjunctival factors that could be evaluated preoperatively probably are not related to the poor results in black patients of filtration surgery noted by some investigators.

Aged

The effect of background intensity on the components of fluctuation as determined by threshold-related automated perimetry.

We studied the effect of various background intensities on the components of fluctuation by testing 20 healthy subjects on the Humphrey Field Analyzer. Our results show little difference in the total fluctuation between two low photopic background intensities similar to those commonly used on commercial perimeters: 3.02 dB for 31.5 apostilbs (asb) and 2.77 dB for 3.15 asb. However, an increase in total fluctuation (3.74 dB for 0.315 asb and 4.24 dB for 0.0315 asb) as well as in its short-term, long-term heterogeneous, and interindividual components was seen at mesopic background intensities as compared with the low photopic range. This study suggests that in healthy individuals, little difference exists in the fluctuation resulting from differences in background intensities commonly used on commercial perimeters, whereas mesopic illumination may increase the variability of threshold responses.

Adult

Threshold variability using different Goldmann stimulus sizes.

We tested 10 healthy subjects on the Humphrey Field Analyzer using Goldmann stimulus sizes I-V to determine the effect of varying the area of the stimulus upon threshold fluctuation. Our results show similar components of fluctuation for the size III stimulus as in past studies. However, an increased total fluctuation was observed for Goldmann stimulus sizes I (3.69 decibels) and II (3.17 decibels) and a similar fluctuation for stimulus sizes IV (2.64 decibels) and V (2.51 decibels) as compared to stimulus size III (2.52 decibels). The study suggests no advantage results in reduced threshold fluctuation by changing the Goldmann stimulus from a size III when testing normal individuals on the Humphrey Field Analyzer.

Adult

Intellectual and adaptive functioning in individuals with Down syndrome in relation to age and environmental placement.

The cognitive and adaptive capacities of 130 individuals with Down syndrome were investigated as a function of age and environmental placement. Intellectual deterioration occurred whether individuals resided at home or in an institutional setting. Social/adaptive deterioration also occurred but with the least decline for those individuals who resided in institutional settings.

Activities of Daily Living

Accelerated tumor growth following experimental burns.

When mice are given a 30% scald burn, the growth of subsequently inoculated Ehrlich ascites tumor is markedly accelerated. This effect, which parallels the well documented suppression of cell-mediated immunity occurring postburn, disappears 10 days postinjury. Possible clinical implications are discussed and an illustrative case report is presented.

Animals