NPDS without or with an autologous scleral implant is a safe procedure reducing the IOP significantly, but probably not sufficient when an IOP below 16 mmHg is required. We found no statistically significant difference between the two groups.

Pulse synchronized PNT gives more reproducible measurements than routine PNT. The agreement between PNT and GAT is poor.

The fast oscillations (FO) of the electro-oculogram were recorded in 102 eyes of 51 normal subjects. We evaluated the normal range and variability of FO parameters, i.e. Rf, which is the average ratio in percentage of the average amplitude in the dark period (AD) and the average amplitude in the light period (AL), and df, which is the average difference between AD and AL in microV. The standing potential was recorded continuously during six subsequent cycles, each consisting of a one minute period in the dark and one minute period in the light. The mean +/- standard error for Rf was 112.9 +/- 1.3% and 69.6 +/- 5.3 microV for df. There was no statistically significant difference between both genders or different age groups. Rf and df were calculated using a different number of dark-light cycles. In normal subjects both the Rf and df show no difference when only 4 dark-light cycles are used in calculating these values. Therefore there seems no additional advantage in performing as many as 6 cycles. Using 4 dark-light cycles reduces the duration of the examination (8 vs. 12 min) of the fast oscillations and in particular when examining both fast and slow oscillations successively it might be useful to reduce the time of the examination.

We determined the relative importance of electrode derivation, stimulus type, spatial frequency and contrast in determining the relative size of the late negative and early positive responses of motion elicited VEPs. Seven subjects aged 22-48 years with normal vision were tested binocularly. Motion onset and motion reversal were employed as modes of stimulus presentation. For both, pseudo-random one-dimensional noise patterns whose peak power was at 5.2, 2.6, 1.3, 0.325 and 0.1625 cycles per degree (cpd) were stimuli. Contrasts were 70% and 5%. Active electrodes were placed at Oz, 5 cm to the left of Oz, 5 cm to the right of Oz and a frontal midline position (Fpz) and referenced to linked mastoids. Transient motion reversal elicited a prominent positive response present in all subjects and at low contrasts. Motion onset VEPs have a complex waveform which may be either predominantly positive or negative. The most important variables in determining whether a prominent positivity or negativity is present in the motion onset VEP are the contrast and the spatial frequencies. Data such as these are first efforts in developing recommendations for the motion VEP.

Purpose:To evaluate the rate of false negative results with the Heidelberg Retina Tomograph (HRT II) in a glaucoma practice. Design: Cross-sectional study. Methods: We analyzed the HRTs taken between October 2002 and October 2003 in our glaucoma clinic, and selected the patients who had a good quality image (SD Ͻ 40 µ) with a normal Moorfi eld's Regression Analysis (MRA). A masked independent observer classifi ed those patients as normal, glaucoma suspect, or glaucomatous on the basis of optic disc stereo photos (ODP) and at least 2 consecutive reliable automated perimetries. The diagnosis of glaucoma was based on a glaucomatous optic disc with a congruent, reproducible visual fi eld defect. Results: Four hundred and fi fty patients who had undergone an HRT examination were analyzed. One hundred and nine patients had an HRT classifi ed as normal on the MRA, and a good quality image. Fifteen of those 109 patients (13.7%) were classifi ed as glaucomatous on the basis of an abnormal ODP with corresponding visual fi eld defect. Seven (6.4%) patients were classifi ed as glaucoma suspect. Conclusion: Fourteen percent of glaucoma patients with glaucoma remained undetected with the HRT II Moorfi eld's regression analysis as a sole means to detect glaucoma.