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Charcot-Marie-Tooth disease caused by mutations of the myelin protein zero gene demonstrates considerable phenotypical variability. We describe a 45-year-old female with a peripheral neuropathy with demyelinating and axonal features, pes cavus and pupillary light-near dissociation. She was heterozygous for two mutations in the myelin protein zero gene (His81Tyr and Val113Phe), both present on the same allele. Our patient shows a less severe phenotype than previously described patients with a His81Arg mutation. Multiple mutations in the myelin protein zero gene, as well as Charcot-Marie-Tooth with pupillary abnormalities have previously been described in rare instances. However, concurrent occurrence of both phenomena is a novel finding.

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In 1991 the Netherlands Glaucoma Patient Association organized a glaucoma screening survey. This survey was designed to evaluate the effectiveness of a low cost screening setting. During a screening period of 8 days, 1259 subjects over the age of 49 years were examined by a team of non-ophthalmologically trained students. The following screening methods were used: visual field analysis (Henson CFS3000 perimeter), retinal nerve fiber layer photography (Canon non-mydriatic camera), intraocular pressure measurement (Pulsair non-contact tonometer) and determination of the peripheral anterior chamber depth (slitlamp biomicroscope, the van Herick method). In a later stage, subjects with glaucomatous abnormalities in the visual field and/or the photograph were re-examined by a glaucoma specialist using applanation tonometry, gonioscopy, ophthalmoscopy and Humphrey 30-2 visual field analysis. The time taken to conduct the individual screening tests in a subject varied from 1 to 5 min: perimetry took 5 min, photography 2 min, tonometry 3 min and angle-width determination 1 min. Fifty-six (4.4%) subjects showed glaucomatous defects in perimetry and/or photography. Thirty-seven could be re-examined and glaucoma was diagnosed in 16 subjects. Visual field defects and glaucomatous abnormalities in the photograph were confirmed by Humphrey perimetry in 72.7% and 35.7% respectively. Sixty-seven (5.3%) subjects had an intraocular pressure above 21 mm Hg, while no cases of angle closure glaucoma were found in this population. The costs of this screening setting were estimated at F1. 48,60 per screen. A future low cost screening survey might be limited to non-contact tonometry and visual field analysis with the Henson CFS3000 perimeter or a similar device, using suprathreshold testing with a limited number of points. Screening might be performed by non-medically trained employees. The costs of such a screening program may be estimated at F1. 16,- per screen and F1. 1.989,- per glaucoma case using a mobile screening unit (addendum).

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PURPOSE: To determine whether, in a clinical setting, scanning laser polarimetry and retinal nerve fiber layer photography provide equivalent information on the retinal nerve fiber layer. METHODS: We prospectively studied 60 patients with glaucoma or ocular hypertension and 24 healthy subjects. With scanning laser polarimetry, an estimate of the cross section of the retinal nerve fiber layer was obtained. By using a photographic reference set, we quantified photographs of the retinal nerve fiber layer. Visual fields were used to relate the results of both methods to functional damage. RESULTS: The scanning laser polarimetry measurements yielded reproducible cross-section values (coefficient of variation, 6.6%). Comparison of cross-section values and photograph scores gave Pearson correlation coefficients smaller than r = .4 (P < .01), improving to a maximum of r = .53 after compensation for offset. When cross-section values were compared to the mean deviation of the visual field, the Spearman correlation coefficients varied from an r of -.34 to -.53 (P < .01). Correction for offset resulted in an r of -.54 to -.65. When photograph scores and mean deviation of the visual field were compared, the Spearman correlation coefficients varied from an r of -.65 to -.71 (P < .01). CONCLUSIONS: Because r was maximal at .53, the information on the retinal nerve fiber layer obtained with scanning laser polarimetry and photography seems not equivalent. This result could not have been because of lack of reproducibility. Although the results suggested possible offset in scanning laser polarimetry, other methodologic differences must be considered to explain the differences between the two techniques.

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PURPOSE: We developed a new quantitative approach for the evaluation of diffuse atrophy of the retinal nerve fiber layer. METHODS: A simultaneous, visually supported grading system was designed, which consisted of a set of 25 reference photographs, numbered from 25 (broad, clearly striated nerve fiber bundles) to 1 (no nerve fibers visible). We prospectively evaluated this method by matching 60 retinal nerve fiber layer photographs of patients with glaucoma or ocular hypertension and normal subjects to the reference photographs twice by three observers with varying experience levels in evaluating retinal nerve fiber layer RESULTS: Intraobserver and interobserver reliability, evaluated by the intraclass correlation coefficient statistics, was excellent (intraclass correlation coefficient > 0.8). Intraclass correlation coefficients within observers were from 0.89 to 0.98 (lower limits 905% confidence interval, 0.84 to 0.97), and intraclass correlation coefficients between observers were from 0.81 to 0.91 (lower limits 95% confidence interval, 0.50 to 0.87). Clinical validity, in which the scores for upper and lower halves of photographs were compared with the mean deviation of the Humphrey 30-2 visual field program by using the Spearman correlation coefficient, was substantial (r = -.68, P < .01 for upper photo score and lower field mean deviation, r = -.53, P < .01 for lower photo score and upper field mean deviation). CONCLUSIONS: By using a reference set of of photographs of the retinal nerve fiber layer, we defined a method to derive a quantitative measurement of retinal nerve fiber layer with good reliability and to extend evaluation of retinal nerve fiber layer photographs to nonspecialists.

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We treated 34 eyes of 32 patients who developed a hypotonous maculopathy after a trabeculectomy with mitomycin C with various treatment strategies. Placement of a Megasoft Bandage Contact Lens in 24 eyes did not result in a notable increase in intraocular pressure or visual acuity. Intrableb injection of autologous blood in 22 eyes resulted in a mean +/- standard deviation (S.D.) increase in intraocular pressure from 4.3 +/- 1.8 mm Hg before injection to 8.6 +/- 4.6 mm Hg after injection. Mean logMAR visual acuity improved from 0.71 +/- 0.40 to 0.32 +/- 0.25. After a surgical revision of 16 eyes, intraocular pressure increased from 4.1 +/- 1.9 mm Hg to 11.3 +/- 4.0 mm Hg, and logMAR visual acuity improved from 0.61 +/- 0.30 to 0.22 +/- 0.24. At the last follow-up examination (12.2 +/- 5.1 months after the trabeculectomy), 31 eyes (91.2%) had an intraocular pressure greater than 6 mm Hg. Hypotonous maculopathy after trabeculectomy with mitomycin C can be treated successfully by autologous blood injection and surgical revision of the filtration site.

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We evaluated the histopathologic findings in seven patients who underwent surgical revision of the filtration site after trabeculectomy with mitomycin C because of persistent hypotonous maculopathy. Light microscopic examination of subconjunctival tissue and sclera demonstrated hypocellularity of fibroblasts and disruption of the normal architecture. Tissue fragments at the margin of the bleb wall demonstrated scarring and contained multiple fibroblasts. Additionally, we investigated the histopathologic changes in an eye obtained from a patient who died one week after a trabeculectomy with mitomycin C. Transmission electron microscopy showed myelin figures, increased melanolipofuscin granules, vacuolated cytoplasm, and disrupted mitochondria of the ciliary body epithelium underlying the site of mitomycin C application. On the basis of these findings, both overfiltration because of tissue disorganization of the filtering bleb and aqueous hyposecretion because of ciliary body toxicity might be involved in the causes of persistent hypotony after mitomycin C trabeculectomy.

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After reviewing the records of 111 patients with Fuchs' heterochromic iridocyclitis, we studied the therapy and prognosis of secondary glaucoma in 30 of these 111 patients (27%) who had glaucoma or could be considered glaucoma suspects. Maximal medical therapy was unsuccessful in 22 of the 30 patients (73%). Surgical intervention (mostly trabeculectomies, half with 5-fluorouracil) successfully controlled intraocular pressure (< or = 21 mm Hg with or without medication) in 13 of the 18 operated-on patients (72%) after a mean follow-up of 26 months. All successfully operated-on patients retained a visual acuity of 20/80 or better. We had favorable results, possibly because of modern surgical techniques (use of 5-fluorouracil, sodium hyaluronate) or earlier surgical intervention, or both.

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In 67 eyes of 46 patients with chronic primary angle closure glaucoma, the effect of peripheral iridectomy in lowering the intraocular pressure was investigated retrospectively. In the majority of cases the pressure was reduced. For the whole population the mean reduction was 3.9 mmHg (SD 6.7 mmHg). The presence or extent of peripheral anterior synechiae showed no significant correlation with the amount of pressure reduction. A peripheral iridectomy is still recommended as first step in the treatment of primary angle closure glaucoma.

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To calibrate oculokinetic perimetry (OKP) as developed by Damato in terms of conventional perimetric threshold values, 33 eyes with either glaucoma or ocular hypertension were tested with a standard Humphrey Field Analyzer using the Central 30-2 test and twice with a 26-point OKP chart. The frequency of seeing of the OKP test spot was plotted against 30-2 thresholds. This showed a weak relation between the two tests. Subsequently eyes that were considered to have had poor fixation were omitted, but false positive and false negative results still occurred in 19 remaining eyes. To check whether Troxler's effect (local adaptation) might have caused false positives, 6 subjects were tested with OKP, controlling the fixation times. Increasing the fixation time from 'very short' to 2 and 5 seconds yielded more 'not seen' responses in OKP. False negative data were found to occur preferentially in border areas of visual defects. The average frequency of seeing curve over all data showed a 50% frequency of seeing for the OKP stimulus at a 14.6 dB equivalent conventional threshold value. The spreading of the curve was 7 dB (95% confidence interval 28 dB).

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In a total of 24 randomly selected eyes of glaucoma patients, tested with the automated (single stimulus) and the manual (multiple stimulus) modes of the semi-automated Peritest perimeter, the numbers and depths of defects were compared as estimated with these two different measurement strategies. It was found that with the manual technique considerably less defects were detected than with the automated strategy.

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Deposition of a fibrin-like material leading to a membrane in the pupillary opening is described in glaucoma patients following extracapsular cataract extraction and intraocular lens implantation. The fibrinoid reaction was observed in 4 out of 57 eyes (7%), all operated on within two years by the same surgeon (CTL). The fibrinoid reaction appeared 2 to 15 days postoperatively in glaucoma patients on whom iridoplasty or synechiolysis had been performed during surgery. It seems advisable to give such patients long-acting subconjunctival steroids at the end of the operation.

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Fifty advanced glaucoma patients with central visual field islands were evaluated before and after intra-ocular surgery with respect to visual acuity and visual field behavior. Thirteen patients underwent a cataract extraction, and 37 a filtering procedure. Visual acuity generally improved to a certain extent after lens extraction, and deteriorated after filtering surgery. For both groups the visual field island became somewhat larger with respect to the surface area, but the foveal value was usually lower after the operation. There was no clear relationship between visual acuity and foveal values or the surface area of the central island. One patient suffered unexplained loss of central vision.

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A perimetric method using blue stimuli on a yellow background was compared with perimetry using white stimuli on a white background as a method of detecting glaucomatous damage. Meridian perimetry was used with an adapted Tübinger perimeter. The difference between the blue-on-yellow meridian and the white-on-white meridian was subdivided into two parts: the general blue sensitivity loss (GBSL), probably due to optical factors, and the corrected blue sensitivity loss (CBSL), probably due to glaucoma. Nine normals, fourteen primary open angle glaucoma (POAG) patients and nine ocular hypertensives (OHT) were tested. All POAG patients and some of the OHT group showed higher CBSL values than the controls. The blue-yellow meridian showed broader and deeper defects than the white-white meridian in all of the POAG group; some of the OHT group had defects in the blue-yellow meridian that were not present in the white-white meridian. In conclusion, blue on yellow perimetry shows promise as a method for more sensitive detection of early glaucomatous damage.

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The Henson Central Field Screener is a recently marketed, relatively inexpensive campimeter with semi-automated registration of responses. The strategy used is suprathreshold, eccentricity-compensated, multiple stimulus static perimetry. The clinical usefulness of this apparatus was tested in a number of glaucoma patients, glaucoma suspects and normals, as well as in subjects with other ocular disorders, for whom stable visual fields as tested with other perimeters were available. The results obtained with the Henson Screener are generally in agreement with the known defects. The apparatus has some drawbacks, however.

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Ten normal controls, ten ocular hypertensive patients, ten high tension, 12 medium tension and nine low tension glaucoma patients were studied prospectively by means of automated static perimetry. Multiple double threshold measurements were obtained during at most three years. A computer algorithm estimated for each visual field the Individual General Sensitivity IGS, in which local defects do not contribute. Thus we were able to estimate pure general reduction of sensitivity by comparing the IGS to age-corrected normal reference values. No significant difference in mean general reduction of sensitivity was found between the glaucoma patients and the normal group. Patients with local defects in one field half only also showed IGS values not different from normals. Our findings indicate that the impression of 'general' sensitivity loss may be caused by the presence of multiple local defects, and is not a phenomenon in itself.

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