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G C Gusek

Publications and source records attributed to G C Gusek.

25 records · Page 2Linked to original sources
PubMed1988

Pseudopapilledema associated with abnormally small optic discs.

Using Littmann's method for correcting the magnification of central fundus photographs, we determined the absolute size of 35 unselected optic discs with pseudopapilledema. The optic disc area (1.95 +/- 0.33 mm2 (mean and SD)) was significantly (P less than 0.001, Student's t-test ) smaller than standard values of normal unselected optic nerve heads (2.73 +/- 0.76 mm2). There was no cupping in the discs with pseudopapilledema. Coefficients of variation for intraobserver re-evaluation were 0.045, and for interobserver re-evaluation 0.08. The markedly reduced optic disc size coincide with an abnormally small optic nerve scleral canal may inhibit the intraaxoplasmatic flow with secondary swelling of the juxtapapillary optic nerve fibers. This may lead t o prominence and indistinct borders of the optic disc. Pseudopapilledema might be related to optic nerve head drusen, which are also associated with abnormally small optic discs.

Adolescent↗
PubMed1988

Correlations of the neuroretinal rim area with ocular and general parameters in normal eyes.

The neuroretinal rim as equivalent of the retinal nerve fibers is the target in the evaluation of glaucomatous optic nerve heads. Its area was measured in absolute size units using photographs of 234 normal optic disks and correcting the photographic magnification according to Littmann's method. High myopic eyes (less than -8.00 dptr) were excluded. The mean rim area was 2.09 +/- 0.60 (0.80-3.80 mm2). It was significantly correlated (p less than 0.00001) to the optic disk area. In optic disks without cupping, the neuroretinal rim area was identical with the disk area (r = 1.0, slope of the regression line = 1.0). In disks having cups with temporal flat slopes, the rim area increased by a factor of 0.71 with the disk size, in disks with circular steep cups, by a factor of 0.26. This interindividual variability and the correlations between rim and disk area might be clinically important for morphometry of glaucomatous optic nerve heads. There were no significant correlations between rim area and age, sex, refraction or axial length.

Adolescent↗
PubMed1988

Optic disc, cup and neuroretinal rim size, configuration and correlations in normal eyes.

Four hundred and fifty-seven unselected normal human optic nerve heads of 319 subjects (163 men, 156 women, mean age 42.7 +/- 19.6 years) were evaluated by magnification-corrected morphometry of optic disc photographs. Mean optic disc surface measured 2.69 +/- 0.70 mm2 (0.80-5.54 mm2), mean diameter horizontally 1.76 +/- 0.31 mm (0.91-2.61 mm), and vertically 1.92 +/- 0.29 mm (0.96-2.91 mm). The form was slightly vertically oval. Optic cup area averaged 0.72 +/- 0.70 (0.00-3.41 mm2), mean horizontal cup diameter 0.83 +/- 0.58 mm (0.00-2.08 mm) and mean vertical diameter 0.77 +/- 0.55 mm (0.00-2.13 mm). The cup was significantly (P less than 0.0001) larger in discs with steep "punched-out" cups (1.37 +/- 0.62 mm2) compared to discs having cups with temporal flat slopes (0.59 +/- 0.39 mm2). Neuroretinal rim area ranged from 0.80 to 4.66 mm2 (mean 1.97 +/- 0.50 mm2), and was significantly correlated (P less than 0.00001) to the optic disc area. It was broadest in the inferior optic disc region (P less than 0.001), followed by the superior, nasal and temporal (P less than 0.001) regions. Horizontal cup/disc ratio (mean 0.39 +/- 0.28, minimum 0.00, maximum 0.87) was larger in 426 (93.2%) optic discs than the vertical one (mean 0.34 +/- 0.25, minimum 0.00, maximum 0.85). Concerning optic disc area, side differences of 0.10 mm2 or less were detected in 28%, of 0.2 mm2 or less in 46% and of 0.50 mm2 or less in 80% (cumulative frequencies). Concerning neuroretinal rim area, side differences of 0.10 mm2 or less were found in 31%, of 0.20 mm2 or less in 52% and of 0.50 mm2 or less in 84%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Optic nerve head drusen associated with abnormally small optic discs.

Using Littmann's method for correcting the magnification of central fundus photographs we evaluated the absolute optic disc size in 26 eyes with visible optic nerve head drusen. The optic nerve head area in these eyes (1.79 + -0.50 mm2) was significantly smaller (p less than 0.001) than normal standard values previously determined (2.89 + -0.76 mm2). The drusen were most commonly located and most densely packed at the upper and lower optic disc border. The coefficients of variation of the method's reproducibility were 0.06 for intraobserver and 0.11 for interobserver determination. The abnormally small optic disc indicating an abnormally small optic nerve scleral canal may inhibit by mechanical compression the axonal flow within the optic nerve fibers. This may ultimately lead to drusen formation. Pseudoneuritis also associated with an abnormally small optic disc may be a preceder of acquired optic nerve head drusen.

Adolescent↗
PubMedDate not supplied

[Optical sector iridectomy: an alternative to perforating keratoplasty in Peters' anomaly].

BACKGROUND: The penetrating keratoplasty as an early surgical procedure to present deep irreversible amblyopia in patients suffering from Peters' anomaly has shown an extremely high risk for transplantat failure. PATIENTS AND METHODS: From 1980 to 1992 20 sectoriridectomies (6 bilateral, 1 twice because of progressive corneal opacification in the area of sectoriridectomy) were performed in 13 patients with Peters' anomaly (diameter of corneal opacification greater than half of the corneal diameter). The mean age at surgery was 1 year and 9 months, the mean follow-up was 3 years and 6 months. Preoperatively the visual function was uncertain light perception in all eyes with marked horizontal nystagm. Except for two eyes (24 mm Hg) the intraocular pressure (IOP) was normal. RESULTS: In 9 (47%) eyes the visual acuity was 20/500 to 20/200. One eye showed certain light fixation, one eye hand movement. In one eye the visual function remained uncertain light perception "after combined lens aspiration." One eye developed a phthisis after combined anterior vitrectomy and lens aspiration for PHPV. In three eyes, the visual outcome could not be determined certainly, in three eyes, the follow-up failed. In two eyes the IOP was regulated under topical antiglaucomatous eye drops, in the other eyes the IOP was normal. CONCLUSIONS: In contrast to penetrating keratoplasty sectoriridectomy seems not to be followed by secondary glaucoma postoperatively. The visual outcome is comparable to that after early keratoplasty. We recommend "optical" sectoriridectomy as an alternative surgical approach to early penetrating keratoplasty in patients suffering from Peters' anomaly.

Amblyopia↗