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To quantify the relationship between optic nerve head tomography and perimetric sensitivity in patients with papilledema.Eight patients with variable degrees of recently diagnosed papilledema associated with idiopathic intracranial hypertension (IIH) were evaluated with confocal scanning laser ophthalmoscopy (CSLO) and automated perimetry. Patients were followed up with serial measurements over a period of 5 to 30 months (mean +/- SD, 17.1 +/- 9), while under medical treatment (acetazolamide). The tomographic parameters, volume above reference (VAR), volume above surface (VAS), effective mean height (EMH), and maximum height in contour (MxHC), were obtained by tomography, either globally or from predefined disc sectors. The perimetric indices, mean deviation (MD) and pattern SD (PSD), were evaluated. The results from patients' right eyes and the individual intereye differences in both tomographic and perimetric parameters, were statistically evaluated by nonparametric correlational (Spearman) and repeated measures (Wilcoxon) analyses.At baseline, all tomographic parameters were negatively correlated with MD in global (r = -0.8) and sectorial (r = -0.6) evaluations. The interocular differences in overall tomographic parameters were correlated with corresponding differences in perimetric MD (r = -0.8) and PSD (r = 0.6). During the follow-up period, volumetric disc parameters decreased (P0.02), whereas perimetric MD increased (P = 0.02) at comparable times.In patients with recently diagnosed papilledema, optic nerve head tomographic abnormalities are quantitatively correlated with visual field sensitivity losses. Therapeutic improvement of volumetric parameters may be paralleled by recovery in perimetric sensitivity. The data support the possible use of both techniques in combination to monitor the amount of papilledema and the effectiveness of treatments designed to reduce intracranial hypertension.

At present, episcleral plaque brachytherapy and charged particle or photon irradiation are the most commonly employed methods in ocular and adnexal conservative treatments. In the near future, a different therapeutic approach to these malignancies could be represented by a new device based on electron beam emission. The equipment used consists of an electron accelerator originally developed for intraoperative radiotherapy, modified to fit ocular pathologies. Adequate collimators and an enhanced mechanical accuracy are required for this special practice. An operative planning for epibulbar, adnexal and intraocular tumors is described, discussing its rationale for possible applications. Experimental tests using phantoms and Gafchromic® films are in progress. As all conservative treatments, the main gaol of this activity is the maintenance of a good visual function.

The possibility of a relation between high myopia and lens opacity was studied. For this research, the Lens Opacity Meter 701 was used. The lens opacity values measured in 91 high-myopic eyes were compared with those measured in a control group of 106 emmetropic eyes. This comparison showed that myopic had always higher lens opacity values than emmetropic ones, and this result was statistically significant after the age of 20.

To evaluate the correlation of pattern electroretinogram (PERG), an index of inner retinal function, with confocal scanning laser (CSLO) optic disc structural parameters in ocular hypertension (OHT).Thirty-four patients with OHT, normal white-on-white (Humphrey 30-2) perimetry, and normal clinical optic discs were examined with PERG and CSLO disc analysis. Two groups of normal subjects (n = 38 and 18, for PERG and CSLO, respectively) and a group of 12 patients with early open-angle glaucoma (EOAG) were also tested. Pattern electroretinogram amplitudes were measured in response to sinusoidal gratings of variable spatial frequency (0.58-5.8 cycles/degree), modulated in counter-phase at 7.5 Hz. Morphometric optic disc parameters were obtained by the Heidelberg Retina Tomograph (HRT), either globally or from predefined disc sectors. In addition to standard parameters, the cup shape measure, an index of depth variation and steepness of the cup walls, was determined.In individual OHT patients, PERG amplitudes at 2.6 cycles/degree were negatively correlated with cup shape measures (r = -0.43, P0.01) obtained from analysis of the inferotemporal (IT) sector. No significant correlations were found for the other parameters. On average, the cup shape measures derived from IT sector or global analysis were significantly (P0.01) worse, and closer to the measures of EOAG patients, in OHT patients with abnormal PERG compared with those with normal PERGs. The cup shape measure displayed a low sensitivity (20%) and a high specificity (100%) in predicting PERG abnormalities in individual OHT patients.The results indicate that in OHT there is a significant although weak correlation between PERG amplitude and the shape of the optic disc cup, suggesting a parallel involvement of both function and morphology. Combined PERG and optic disc cup structural analysis is of potential diagnostic value to detect early damage to optic nerve head in individual OHT patients.

To evaluate in glaucomatous eyes the photopic electroretinogram (ERG) negative response (PhNR), a component that follows the b-wave peak and is thought to be correlated with inner retinal activity.Eleven patients with open-angle glaucoma (OAG) and moderate field loss (Humphrey 30-2 [Humphrey Instruments, San Leandro, CA] mean deviationor = -6 dB), eight with ocular hypertension (OHT), and eight age-matched normal subjects were tested. Optic discs of patients and control subjects were evaluated by confocal scanning laser ophthalmoscopy. ERGs were recorded to long-duration stimuli (250 msec) of photopic luminance (78 candelas [cd] /m2), presented in the macular region (12 degrees x 12 degrees field size) on a steady, adapting background. Amplitudes of the a-wave and b-wave and the PhNR were measured. Pattern reversal ERGs to 30-minute checkerboards were also recorded from patients and control subjects.Compared with control subjects, patients with OAG showed reduced PhNR (average reduction: 62%, P0.01), but normal a- and b-wave amplitudes. In patients with OHT, PhNR and a- and b-wave amplitudes did not differ from control values. In individual patients with OAG, PhNR amplitudes were correlated positively with pattern ERG amplitudes (r = 0.80; P0.01) and central (12 degrees) perimetric mean deviations (r = 0.68; P0.05) and negatively with cup-to-disc area ratios (r = -0.79; P0.01) and cup shape measures (r = -0.78; P0.01).Similar to that found in monkeys with experimentally induced glaucoma, the PhNR is selectively altered in human glaucoma. The correlation between PhNR losses and clinical parameter abnormalities suggests that this component depends on inner retina integrity and may be of clinical value for detecting glaucomatous damage.

Visually dependent postural stabilization decreases as a consequence of a long-standing reduction of visual cues in patients affected by congenital nystagmus. The aim of the present study was to verify whether the changes in postural control in this group of patients are due to ocular oscillations or to reduced visual acuity. Therefore, postural control was evaluated when the nystagmus was blocked by the blocking position or by prisms and compared with the postural score observed in a group of normal controls whose visual acuity had been artificially reduced to the same level as that of the patients using Bangerter's filters. The results show a statistically significant improvement of visually dependent postural stabilization when ocular oscillations are inhibited either by the gaze blocking position or by prisms. They also show that postural control in normal subjects with Bangerter's filters is reduced, but is still significantly better than that observed when ocular oscillations are inhibited in patients affected by congenital nystagmus. Our data strongly support the role of ocular oscillations in visually dependent postural control, since postural impairment recovered under any condition in which ocular oscillations were abolished, despite differences in visual acuity. Our data also show that reduced visual acuity decreases visually dependent postural control to a lesser degree than ocular oscillations. This could be due to the fact that ocular oscillations are a disturbing input, usually inhibited centrally, in order to avoid oscillopsia. This mechanism is probably responsible for the reduced role of visual cues in the postural control in this group of patients. The reduction of visual acuity, by comparison, merely causes a decrease in visual cues, depending on the degree of visual loss. It can be concluded that the impaired postural control in patients affected by congenital nystagmus is mainly due to ocular oscillations, with reduced visual acuity creating a secondary effect.

To evaluate retinal, cone-mediated flicker sensitivity (CFS) in age-related maculopathy (ARM) by quantifying response gain and threshold of the focal electroretinogram (FERG) to flicker modulation.Nineteen patients with ARM (visual acuityor =20/30) and 11 age-matched control subjects were examined. Twelve patients had less than 20 soft drusen in the macular region and no hyper-/hypopigmentation (early lesion), whereas seven had more than 20 soft drusen and/or focal hyper-/hypopigmentation (advanced lesion). Macular (18 degree ) FERGs were elicited by a sinusoidally flickering (41 Hz) uniform field (on a light-adapting background) whose modulation depth was varied between 16.5% and 94%. Amplitude and phase of the response's fundamental harmonic were measured.In both control subjects and patients with ARM, log FERG amplitude increased with log stimulus modulation depth with a straight line (power law) relation. However, the slope (or gain) of the function was, on average, steeper in control subjects than in patients with either early or advanced lesions. Mean FERG threshold, estimated from the value of the log modulation depth that yielded a criterion response, did not differ between control subjects and patients with early lesions but was increased (0.35 log units) compared with control subjects in those with advanced lesions. In both patient groups, but not in control subjects, mean FERG phase tended to delay with decreasing stimulus modulation depth.Retinal CFS losses can be detected in ARM by evaluating the FERG as a function of flicker modulation depth. Reduced response gain and phase delays, with normal thresholds, are associated with early lesions. Increased response thresholds, in addition to gain and phase abnormalities, may reflect more advanced lesions. Evaluating CFS by FERG may directly document different stages of macular dysfunction in ARM.