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J Caprioli

Publications and source records attributed to J Caprioli.

At least 19 recordsLinked to original sources
PubMed2000

Relationship between structural abnormalities and short-wavelength perimetric defects in eyes at risk of glaucoma.

PURPOSE: To determine the relative prevalence of blue-yellow perimetric defects and structural abnormalities of the optic nerve and nerve fiber layer in eyes at risk of glaucoma. METHODS: Seventy-two eyes (of 72 patients) at risk of glaucoma, with normal white-on-white full threshold perimetry, were examined prospectively with blue-yellow full-threshold perimetry (Humphrey). Structural evaluations were conducted with qualitative assessment of stereoscopic color optic disk photographs and monochromatic nerve fiber layer photographs performed independently by three masked examiners (a glaucoma specialist and two glaucoma fellows), and statistical analysis of summary parameters was obtained with scanning confocal laser tomography (abnormal defined as values outside 95% confidence limits established in normal control subjects). RESULTS: Kappa values for interobserver agreement were 0.64, 0.88, and 0.79 for optic disk evaluation and 0.59, 0.60, and 0.61 for nerve fiber layer evaluation. Thirteen (18%) of 72 eyes had blue-yellow abnormalities. A total of 30 eyes (42%) were identified as having a structural abnormality; 29 (40%) had qualitatively determined optic disk abnormalities, 21 (29%) had qualitatively determined nerve fiber layer defects, and 26 (36%) had statistically significant structural abnormalities. Twelve of 13 eyes with blue-yellow defects had a detectable structural abnormality; all 12 had abnormalities identified with disk photography, nine with nerve fiber layer photography, and 12 by scanning laser tomography. CONCLUSIONS: Clinically detectable structural abnormalities frequently coexist with blue-yellow perimetric defects in patients with ocular hypertension. A substantial proportion of patients with ocular hypertension with normal blue-yellow perimetry has early detectable glaucomatous structural abnormalities.

Glaucoma, Open-Angle↗
PubMed2000

Retinal ganglion cell death in experimental glaucoma.

AIMS: To determine whether parasol retinal ganglion cells (magnocellular pathway) are selectively lost in the primate model of glaucoma. METHODS: Ocular hypertension was induced in one eye of six Macaca fascicularis monkeys for 6-14 weeks. The retinal ganglion cells in these eyes were labelled retrogradely with the tracer horseradish peroxidase (HRP) implanted into the optic nerve and subsequently examined in retinal whole mount preparations. The degree of retinal ganglion cell loss was estimated from Nissl stained tissue by comparison with the contralateral untreated control eye. RESULTS: In the three glaucomatous retinas with the best labelling 1282 cells could be classified, of which 182 were parasol cells and 1100 were midget cells. Linear regression analysis did not demonstrate a significant reduction in the proportion of parasol to midget cells with increasing cell loss (regression slope 0.023, 95% CI -0.7 to 0.11). Compared with the control eye the cell soma of the remaining retinal ganglion cells in glaucomatous eyes were reduced in size by 20% for parasol cells (p=0.003) and by 16% for midget cells (p <0.001). CONCLUSION: The results of this study do not support the hypothesis that selective loss of parasol retinal ganglion cells occurs in experimental glaucoma. In addition, the change in cell soma size distributions following ocular hypertension suggests that both parasol and midget retinal ganglion cells undergo shrinkage before cell death.

Animals↗
PubMed2000

Scaling the hill of vision: the physiological relationship between light sensitivity and ganglion cell numbers.

PURPOSE: Differential light sensitivity (DLS) in white-on-white perimetry is used as a measure of ganglion cell function to estimate the amount of neuronal damage in glaucoma. The physiological relationship between DLS and ganglion cell numbers is poorly understood. Within small retinal areas, brightness information is summated, so that A * L = C, or A = C/L, where A is target area, L is threshold luminance, and C is a constant. In larger illuminated areas, as with a Goldmann size III target in perimetry, summation is incomplete, so that A(k) = C/L, where k is the coefficient of summation, and 0 < k < 1. This study tests the hypothesis that the target area (A) can be represented by the number of underlying ganglion cells (G) to give G(k) = C/L. METHODS: Normative human data for ganglion cell density within 30 degrees of retinal eccentricity were taken from the literature and corrected for lateral displacement of ganglion cells from the fovea to estimate ganglion cell receptive field density (g). The number of ganglion cell receptive fields within a Goldmann size III target (G) was calculated from target area (A) and receptive field density (g) [G = A (g)]. Normative data for DLS in the central 30 degrees (Humphrey 30-2) were taken from the literature. The coefficient summation (k) was measured empirically at each Humphrey 30-2 test point in 8 normal subjects. The relationship between DLS and G was investigated by plotting DLS as decibels (dB) against G and DLS as 1/L (1/Lamberts) against G(k). The physiological relationship was extrapolated to glaucomatous ganglion cell loss by calculating hypothetical cell losses for 3 and 6 dB sensitivity defects at each test point. RESULTS: Spatial summation increased with eccentricity. The relationship between DLS (dB) and G was curvilinear. The relationship between DLS (1/L) and G(k) was linear (r2 = 0.73). The extrapolation to glaucomatous ganglion cell loss indicated that a proportionally greater loss of ganglion cells is required in the central compared with peripheral visual field for equal losses in dB sensitivity. CONCLUSIONS: The number of underlying ganglion cells, adjusted for local spatial summation, is better reflected by the DLS scale of 1/L than by dB. If spatial summation is unchanged in glaucoma, this scale more accurately reflects the amount of neuronal damage.

Adult↗
PubMed1999

Increased fragmentation of von Willebrand factor, due to abnormal cleavage of the subunit, parallels disease activity in recurrent hemolytic uremic syndrome and thrombotic thrombocytopenic purpura and discloses predisposition in families. The Italian Registry of Familial and Recurrent HUS/TTP.

We investigated here the changes in von Willebrand factor (vWF) multimers in recurrent, sporadic and familial forms of hemolytic uremic syndrome (HUS)/thrombotic thrombocytopenic purpura (TTP) to see whether they are actually proteolyzed in vivo in these patients. Molecular determinants of fragments in vWF were also characterized to identify possible sites of cleavage of the subunit. Unusually large vWF multimers were found in blood of 8 of 10 patients with recurrent HUS/TTP, both in the acute phase and in remission, but never in familial and sporadic cases. Instead, all of the groups showed evidence of enhanced fragmentation of vWF multimers during the acute phase. Increased fragmentation was also shown by decrease in native 225-kD vWF subunit. In recurrent and sporadic HUS/TTP, enhanced fragmentation normalized at remission, but the abnormality persisted in familial HUS/TTP patients. The latter findings suggest that patients with familial HUS/TTP may have a congenital abnormality in vWF processing. Analysis with specific monoclonal antibodies showed the presence of the normal vWF fragments with apparent molecular mass of 189, 176, and 140 kD in all patients; however, in 6 recurrent and in 5 familial cases, novel fragments that differed in size from normal ones were found. The size of these abnormal fragments differed from one patient to another and none of them was ever found in normal plasma. These results documented, for the first time in HUS/TTP, an abnormal cleavage of the vWF subunit that might account for the increased fragmentation observed in these patients.

Acute Disease↗
PubMed1999

Nitric oxide mediates excitotoxic and anoxic damage in rat retinal ganglion cells cocultured with astroglia.

BACKGROUND: Nitric oxide has been implicated in the process of retinal ganglion cell death in glaucoma. OBJECTIVE: To investigate the role of nitric oxide in mediating retinal ganglion cell death in a culture system that models glial-neuronal interactions at the level of the optic nerve head. METHODS: Dissociated retinal ganglion cells from neonatal rats were plated on monolayers of astroglia and identified by retrograde labeling with the fluorescent marker 1.1-dioctadecyl-,3,3,3,tetramethylindocarbocyanineperchlorate. Two days after dissociation, cocultures of retinal ganglion cells and glia were treated with graded concentrations of the nitric oxide synthase inhibitor N-nitro-L-arginine (NNA), and exposed to either anoxia for 1 to 24 hours or excitatory amino acids for 6 hours. Surviving retinal ganglion cells were counted with fluorescence microscopy and expressed as a percentage of retinal ganglion cells surviving in control cultures. RESULTS: Cell survival after anoxia increased in a dose-dependent fashion with exposure to NNA. Mean +/- SD survival rate of retinal ganglion cells after 6 hours of anoxia was 57%+/-10% with NNA treatment compared with 31%+/-3% without treatment (P<.01). When treated with excitatory amino acids, cell survival was 31%+/-6% after administration of N-methyl D-aspartate, 500 micromol/L, and 27%+/-8% after administration of sodium glutamate, 500 micromol/L. Survival was increased in cultures with exposure to NNA, 100 micromol/L, to 53%+/-11% and 69%+/-11%, respectively (P<.01). CONCLUSION: In this coculture of retinal ganglion cells and astroglia, reduction of the glial source of nitric oxide through nitric oxide synthase inhibition provided partial but significant protection against the lethal effects of anoxia and excitatory amino acids on retinal ganglion cells. CLINICAL RELEVANCE: Neuroprotective agents may play a role in patients with glaucoma who have progressive visual field loss, despite satisfactory control of intraocular pressure. Inhibition of nitric oxide synthase at the level of the optic nerve head may contribute to a clinically significant level of neuroprotection.

Animals↗
PubMed1999

Effect of aging on optic nerve appearance: a longitudinal study.

AIM: To determine whether aging causes detectable changes in the appearance of the optic disc. METHODS: A retrospective longitudinal study was performed with quantitative and qualitative evaluations of digitised stereoscopic optic disc photographs of 224 eyes of 224 subjects. There were three groups: 100 normal subjects from the Framingham Eye Study, 68 glaucomatous patients followed longitudinally, and 56 normal subjects and glaucoma patients who had separate sets of disc photos taken on the same day. A disc was considered qualitatively worse if two of three experienced observers agreed that it was worse. Quantitative progression was defined as a >10% decrease in rim/disc area ratio measured with computer assisted planimetry. RESULTS: With quantitative evaluation, normal eyes (mean follow up 13 years) and same day eyes displayed no statistically significant difference in change of rim/disc area ratios (p=0.095), nor in the number of discs that progressed-five of 100 (5%) v two of 56 (4%) respectively. Glaucomatous eyes (mean follow up 9 years) showed a quantitative loss of disc rim in 24 of 68 (35%), and differed significantly from the normal eyes both in the change of rim/disc area ratio (p<0.0005) and number of discs that progressed (p<0.0005). With qualitative evaluation, the number of progressive discs in the glaucomatous eyes (31%) differed significantly (p<0. 0005) from the normal eyes (3%) and the same day eyes (0%). CONCLUSIONS: Over a period of follow up appropriate for long term outcome studies in glaucoma, there was no quantitatively or qualitatively detectable neuroretinal rim loss in normal aging optic nerves with stereoscopic optic disc photographs.

Adult↗
PubMed1999

Hypocomplementemia discloses genetic predisposition to hemolytic uremic syndrome and thrombotic thrombocytopenic purpura: role of factor H abnormalities. Italian Registry of Familial and Recurrent Hemolytic Uremic Syndrome/Thrombotic Thrombocytopenic Purpura.

Familial hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) carry a very poor outcome and have been reported in association with decreased serum levels of the third complement component (C3). Uncontrolled consumption in the microcirculation, possibly related to genetically determined deficiency in factor H--a modulator of the alternative pathway of complement activation--may account for decreased C3 serum levels even during disease remission and may predispose to intravascular thrombosis. In a case-control study by multivariate analysis, we correlated putative predisposing conditions, including low C3 serum levels, with history of disease in 15 cases reporting one or more episodes of familial HUS and TTP, in 25 age- and gender-matched healthy controls and in 63 case-relatives and 56 control-relatives, respectively. The relationship between history of disease, low C3, and factor H abnormalities was investigated in all affected families and in 17 controls. Seventy-three percent of cases compared with 16% of controls (P < 0.001), and 24% of case-relatives compared with 5% of control-relatives (P = 0.005) had decreased C3 serum levels. At multivariate analysis, C3 serum level was the only parameter associated with the disease within affected families (P = 0.02) and in the overall study population (P = 0.01). Thus, subjects with decreased C3 serum levels had a relative risk of HUS or TTP of 16.56 (95% confidence interval [CI], 1.66 to 162.39) within families and of 27.77 (95% CI, 2.44 to 314.19) in the overall population, compared to subjects with normal serum levels. Factor H abnormalities were found in four of the cases, compared with three of the healthy family members (P = 0.02) and none of the controls (P = 0.04) and, within families, factor H abnormalities were correlated with C3 reduction (P < 0.05). Reduced C3 clusters in familial HUS and TTP is likely related to a genetically determined deficiency in factor H and may predispose to the disease. Its demonstration may help identify subjects at risk in affected families.

Adolescent↗
PubMed1998

Test-retest variability of blue-on-yellow perimetry is greater than white-on-white perimetry in normal subjects.

PURPOSE: To compare long-term fluctuation of blue-on-yellow automated perimetry with white-on-white automated perimetry in normal subjects. METHODS: White-on-white and blue-on-yellow automated perimetry were performed on a Humphrey Visual Field Analyzer and an Octopus perimeter, both modified for blue-on-yellow perimetry. The study sample consisted of 31 eyes of 31 normal subjects for the Humphrey perimeter and 33 eyes of 33 normal subjects for the Octopus perimeter. After one practice session, each subject completed four testing sessions over a period of 2 to 8 weeks, each separated by at least 1 day. Each testing session consisted of both white-on-white and blue-on-yellow perimetry performed on one eye; the order of the tests was alternated for successive sessions. Long-term fluctuation (expressed as statistical variance) was calculated for each test location. Intersubject variability (expressed as statistical variance) across all subjects was determined for each test location. RESULTS: On the Humphrey perimeter, the long term fluctuation for blue-on-yellow perimetry (4.07 +/- 3.07 dB2) was significantly greater than that for white-on-white perimetry (1.97 +/- 0.99 dB2; P < .001). Long-term fluctuation increased as a function of eccentricity for both blue-on-yellow and white-on-white perimetry. Short-term fluctuation was significantly greater for blue-on-yellow (0.46 +/- 0.25 dB) than that for white-on-white perimetry (0.29 +/- 0.19 dB; P < .02). Finally, the intersubject variability was significantly greater in blue-on-yellow (13.2 +/- 2.8 dB2) than it was in white-on-white perimetry (4.25 +/- 1.13 dB2; P < .001). Similar results were found with the Octopus perimeter. CONCLUSIONS: Long-term fluctuation and short-term fluctuation of blue-on-yellow perimetry are greater than those of white-on-white perimetry in normal subjects. The increased long-term fluctuation requires appropriate statistical approaches when evaluating serial change of blue-on-yellow perimetry.

Adult↗
PubMed1998

Acquired pit of the optic nerve: a risk factor for progression of glaucoma.

PURPOSE: To examine acquired pit of the optic nerve as a risk factor for progression of glaucoma. METHODS: In a retrospective longitudinal study, 25 open-angle glaucoma patients with acquired pit of the optic nerve were compared with a group of 24 open-angle glaucoma patients without acquired pit of the optic nerve. The patients were matched for age, mean intraocular pressure, baseline ratio of neuroretinal rim area to disk area, visual field damage, and duration of follow-up. Serial optic disk photographs and visual fields of both groups were evaluated by three independent observers for glaucomatous progression. RESULTS: Of 46 acquired pits of the optic nerve in 37 eyes of 25 patients, 36 pits were located inferiorly (76%) and 11 superiorly (24%; P < .001). Progression of optic disk damage occurred in 16 patients (64%) in the group with acquired pit and in three patients (12.5%) in the group without acquired pit (P < .001). Progression of visual field loss occurred in 14 patients (56%) in the group with acquired pit and in six (25%) in the group without pit (P=.04). Bilateral acquired pit of the optic nerve was present in 12 patients (48%). Disk hemorrhages were observed more frequently in the group with acquired pit (10 eyes, 40%) compared with the group without pit (two eyes, 8%; P=.02). CONCLUSION: Among patients with glaucoma, patients with acquired pit of the optic nerve represent a subgroup who are at increased risk for progressive optic disk damage and visual field loss.

Adult↗
PubMed1998

Increasing peripapillary atrophy is associated with progressive glaucoma.

OBJECTIVE: This study aimed to determine the incidence and degree of progression of peripapillary atrophy in progressive and nonprogressive glaucoma. STUDY DESIGN: A retrospective cohort study. PARTICIPANTS: A total of 75 eyes of 75 patients were examined. MAIN OUTCOME MEASURES: Qualitative assessment of optic disc, peripapillary atrophy,and visual field change was performed by three experienced, masked, independent observers. METHODS: Rim-disc area ratio and peripapillary atrophy-disc area ratio were measured at baseline and follow-up with computer-aided planimetry. RESULTS: Among 75 eyes studied with an average duration of follow-up of 8 years (range, 4-19 years), 33 (44%) showed progressive optic disc damage. Twenty-one (64%) of 33 eyes with progressive disc damage showed peripapillary atrophy progression, and 7 (17%) of 42 eyes without progressive disc damage showed peripapillary atrophy progression; this difference was significant (P < 0.01). In groups with and without peripapillary atrophy, no statistically significant differences were found for mean intraocular pressure, baseline rim-disc area ratio, or baseline peripapillary atrophy-disc area ratio. However, optic disc progression and visual field progression were statistically more frequent in the group with peripapillary atrophy progression (75% and 54%, respectively) than in the group without peripapillary atrophy progression (26% and 11%, respectively) (P < 0.01). There was a statistically significant correlation between measurements of peripapillary atrophy area increase and disc rim loss over time (r = -0.35, P = 0.002). CONCLUSION: Progression of peripapillary atrophy is associated with progressive optic disc damage and progressive visual field loss in glaucoma and may be used as a marker for progressive glaucomatous damage.

Adult↗
PubMed1998

Acquired pits of the optic nerve in glaucoma: prevalence and associated visual field loss.

PURPOSE: This study was performed to determine the prevalence of acquired pits of the optic nerve (APON) in glaucoma and the characteristics of associated visual field loss. SUBJECTS AND METHODS: Stereoscopic optic disc photos from 235 patients with a low-tension variety of primary open-angle glaucoma (LTG) and 251 primary open-angle glaucoma patients with intraocular pressures higher than 21 mmHg (HTG) were examined for the presence of typical APON as defined by a standard photograph (Fig 1). Associated visual field loss was evaluated with automated perimetry and patterns of field loss were identified. RESULTS: Out of a total of 486 patients, 63 APON were found in 51 eyes of 44 glaucoma patients. APONs were more prevalent in women. Acquired pits were more frequently (p<0.001) located inferiorly (70%) than superiorly (30%). There was a significantly higher prevalence (p<0.001) of APON in LTG patients (12.7%) than in HTG patients (5.6%). Dense visual field defects within five degrees of fixation occurred in 96% of patients with APON. CONCLUSION: Acquired pits of the optic nerve are more often located at the inferior optic disc than at the superior disc and are nearly always associated with visual field loss close to fixation. In a glaucoma referral center setting, APON are more prevalent in lower pressure glaucoma than in higher pressure glaucoma.

Adult↗
PubMed1998

Slope of the peripapillary nerve fiber layer surface in glaucoma.

PURPOSE: To develop structural markers of early glaucomatous optic nerve damage with confocal scanning laser ophthalmoscopy. METHODS: Custom software was developed to analyze the images of 53 patients with open-angle glaucoma and 43 healthy subjects (matched for age, race, and refractive error), with images acquired with a confocal scanning laser ophthalmoscope. Height values were obtained along radial profiles of the peripapillary nerve fiber layer surface at 5-degree intervals around the disc edge. Two new parameters were derived: mean height and mean slope of the peripapillary nerve fiber layer surface. Mean slope was tested for its independence from a retinal reference plane. A logistic regression analysis was used to determine functions of disease probability. Receiver-operating characteristic (ROC) curves were used to evaluate sensitivity and specificity of peripapillary nerve fiber layer slope and height to discriminate normal subjects from glaucoma patients. RESULTS: Mean (+/-SD) visual field mean deviation in the glaucoma group was -4.8 +/- 3.3 dB. Mean slope (+/-SD) of the peripapillary nerve fiber layer was significantly (P < 0.001) steeper (0.30 +/- 0.12) in glaucoma patients than in healthy subjects (0.11 +/- 0.12). Mean slope values were identical with or without the retinal reference plane. Mean height (+/-SD) values with respect to a retinal reference plane were 45.2 +/- 103 microm in healthy subjects and -65.2 +/- 105 microm in glaucoma patients, which were significantly different (P < 0.001). The differences for mean slope and for mean height between the healthy subjects and the glaucoma patients were greatest inferiorly. The diagnostic precision, sensitivity, and specificity of mean slope were 83%, 85%, and 80%, respectively. The diagnostic precision, sensitivity, and specificity of mean height were 75%, 69%, and 83%, respectively. CONCLUSIONS: Mean peripapillary slope of the nerve fiber layer surface can be used to discriminate between healthy subjects and glaucoma patients with clinically useful diagnostic precision. This parameter is independent of a retinal reference plane and may be particularly useful to detect progressive glaucoma damage.

Diagnostic Techniques, Ophthalmological↗
PubMed1997

Temporal corneal phacoemulsification combined with superior trabeculectomy. A retrospective case-control study.

OBJECTIVE: To determine the results of temporal corneal phacoemulsification combined with separate-incision superior trabeculectomy plus low-dose 5-fluorouracil compared with trabeculectomy plus low-dose 5-fluorouracil. DESIGN: Retrospective case-control study. PATIENTS: Forty consecutive case patients who underwent temporal corneal phacoemulsification combined with superior trabeculectomy plus low-dose 5-fluorouracil (case [combined surgery] group) and 40 control patients, matched for age race, preoperative intraocular pressure (IOP), number of preoperative antiglaucoma medications, and number of 5-fluorouracil injections, who underwent trabeculectomy alone plus low-dose 5-fluorouracil (control [trabeculectomy] group). MAIN OUTCOME MEASURES: Survival analyses for IOP control compared between the 2 groups. METHODS: The medical records of 40 consecutive case patients were reviewed to determine the effect of their treatment on IOP, visual acuity, and requirement for glaucoma medications. In the control group, 40 eyes (1 eye per patient) were randomly selected for comparison with the case group. In both groups, the trabeculectomy was located superiorly and performed with the same technique and using a limbus-based conjunctival flap. In the case group, temporal corneal phacoemulsification immediately preceded trabeculectomy and used a 3.2-mm incision and a 1-piece silicone intraocular lens. All patients received 3 or 4 subconjunctival 5-fluorouracil injections of 5 mg each within the first 11 postoperative days. Patients were followed up for at least 1 year. Success of surgery was defined as an IOP of less than 22 mm Hg and a 20% or more reduction from the preoperative level on 2 consecutive follow-up visits, regardless of the use of antiglaucoma medications. RESULTS: The mean (+/-SD) postoperative IOP was statistically higher in the case group than in the control group at each follow-up interval (P < .05). The mean (+/-SD) IOP reductions at 1 year were 6.8 +/- 5.5 mm Hg and 10.3 +/- 7.6 mm Hg (39.2% +/- 18.8%) in the case and control groups, respectively (P = .04). The reductions in the mean (+/-SD) number of antiglaucoma medications at 1 year were 1.6 +/- 0.9 and 2.0 +/- 1.0 in the case and control groups, respectively (P = .06). In the case group, the mean visual acuity beyond the first postoperative month was significantly better than at baseline (P < .001). Kaplan-Meier survival analysis showed that the cumulative success rates at 2 years were 62.1% and 85.8% in the case and control groups, respectively. The survival time to failure was significantly shorter (P = .04) in the case group by the log-rank test. CONCLUSIONS: Combined surgery for cataract and glaucoma is associated with less long-term IOP reduction compared with trabeculectomy alone despite identical trabeculectomy techniques used in both groups. Nevertheless, combined surgery lowers IOP and reduces the long-term requirement for antiglaucoma medications. This technique is appropriate in selected patients with coexisting cataract and glaucoma.

Aged↗
PubMed1997

Automatic detection of glaucomatous visual field progression with neural networks.

OBJECTIVE: To evaluate computerized neural networks to determine visual field progression in patients with glaucoma. METHODS: Two hundred thirty-three series of Octopus G1 visual fields of 181 patients with glaucoma were collected. Each series was composed of 4 or more reliable visual fields from patients who had previously undergone automated perimetry. The visual fields were independently evaluated in a masked fashion by 3 experienced observers (K.N.-M, M.W., and J.C.) and were judged to show progression based on the agreement of 2 observers. The stable and progressed series were matched for mean defect at baseline. The threshold data were submitted to a back propagation neural network that was trained to classify each series as stable or progressed. Two thirds of the data were used for the training and the remaining one third to test the performance of the network. This was repeated 3 times to classify all of the series (changing the training and test series). RESULTS: Fifty-nine series of visual fields showed progression and 151 were judged stable. Neural network sensitivity was 73% and specificity was 88% (threshold for progression = 0.5). The concordance of the neural network with the observers was good (0.50 < or = kappa > or = 0.64). CONCLUSIONS: A neural network can be trained to recognize visual field progression in good concordance with experienced observers. Neural networks may be used to aid the physician in the evaluation of glaucomatous visual field progression.

Aged↗