Autoregulation of ocular blood flow during changes in intraocular pressure. Preliminary results

Visual evoked potentials were recorded in six normal subjects and in three patients with primary open-angle glaucoma, while intraocular pressure was artificially elevated in stepwise increases. The resulting perfusion-pressure amplitude curves in our controls showed a kink, which can be interpreted as a sign of vascular autoregulation. No kink was observed in the curves of our glaucoma patients, which we interpret as indicating a lack of vascular autoregulation in primary open-angle glaucoma.

Flicker fusion frequency and organic syndrome in alcoholics

Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.

[Effect of various stimulation filters on tear film breakup time]

The tear break-up was determined in 30 patients with healthy eyes aged from 18 to 67 using two different types of filter combinations: (1) Schott Filter OG 530 and Schott Filter BG 12. (2) Schott Filter OG 530 and Zeiss Filter 485. In view of the filter characteristics, we expected a reduction of the variance of the tear break-up time with the second filter combination. This did not occur. There was no difference between the two filter combinations described according to the Wilcoxon Test on the 5 percent level. The reasons are discussed.

[Influence of a barrier filter on tear film breakup time]

In 30 healthy volunteers the tear-film break-up times of both eyes were determined, comparing one eye with a cut-off filter (customarily used in fluorescein angiography (Schott OG 530, thickness 3 mm] with the common method, not using this filter, in the other eye. By using the filter the variance of observed break-up times is decreased, and the time elapsing after the administration of the dye no longer influences the break-up time significantly. The filter described here is therefore recommended for determining the tear-film break-up time.

[Factors influencing the variability of tear film break-up time]

Tear film break-up time was measured on 6 consecutive workdays in 6 subjects without eye disease selected at random. The reasons for the wide range of scatter in the values measured were investigated by variance component estimation. It was found that intraindividual variance is by far the most important factor influencing the overall variance of the measured values. Therefore, caution is called for when judging the stability of the precorneal tear film by the tear film break-up time in healthy individuals.

Post mortem recovery of mandibular osseous graft with cellulose acetate filter. A case report

A surgical procedure was performed to re-establish both aesthetics and functional form to a post partial mandibulectomy patient. A particulate, autogenous osseous graft from the hip was supported by a mandibular tantalum splint lined with a cellulose acetate filter. The patient developed metastatic carcinoma in the donor graft site and lung. The mandibular graft and supporting tissue was removed postmortem and examined histologically. It was observed that normal bone reconstruction was taking place and that union of mandibular bone and graft was evident. Secondary squamous cell carcinoma had invaded the symphysis area of the graft. It is also of interest to note that the tumour was mot able to penetrate those areas where the cellulose acetate filter was present.