Retinal colour duplex scanning during LASIK-ring suction with different keratomes.

PURPOSE: The purpose was to measure the blood flow velocity during the suction phase of LASIK. SETTING: University Eye Hospital, Martin-Luther-University Halle-Wittenberg, Halle, Germany. METHODS: Papillary blood flow velocity was measured by colour Doppler sonography. Suction rings of four different manufacturers were applied in 30 healthy volunteers without eye diseases all of normal blood and eye pressure. The velocity of the blood flow in the central retinal artery was measured before, during and after suction. RESULTS: When Hansatome (Bausch & Lomb) and M2 (Moria) rings were used, no blood flow velocity was detected during suction in 90% of all cases. These rings were compared to the SKBM standard suction ring (Alcon) and the Krumeich non-IOP ring, in which no blood was present in only 56.67% (p < 0.05) and 10% (p < 0.001) of cases respectively. Moria, Alcon and Krumeich Lasitome rings performed equally well during the recovery phase compared with the original values. An exception is the Hansatome ring (Bausch & Lomb), with lower velocities when evaluated after 30 minutes (p < 0.01). CONCLUSIONS: During the ring suction phase of LASIK, the rings tested reduce velocity differently.

[The acid-base balance in the blood of calves of different breeds in a mother cow herd raised on deep straw and strawless conditions]. / Der Säure/Basen-Status im Blut von Kälbern verschiedener Rassen in einer Mutterkuhherde auf Tiefstreu und bei strohloser Haltung.

The influence of two different animal loose housing systems (deep litter resp. gum lying area/slatted floor) with additional calf pen on blood gases and buffer systems in the blood of 19 calves of the breed Deutsche Schwarzbunte and 20 calves of the breed Deutsche Rotbunte of both sexes in a suckler cow herd was examined in a period from the first to the sixth month of life. The pH of the blood remains within the well-known small limit of variability, and no exogenic influences could be seen. Age dependent course up to the third or fourth month of life found out in the factors of oxygen content and oxygen transport, which reflect the development to adults. The pCO2 is higher in calves kept on slatted floor, and the difference is significant in the second and sixth month of life. No significant differences found out in buffer base between the loose housing systems but a slow decrease is perceptible with the development to ruminant conditions. In the behaviour of calves no significant differences could be seen but calves on slatted floor had some more distance to their mothers. No sex and breed specific differences found out in behaviour or physiological data. In conclusion, an extensive suckler cow management in different equipped loose housing systems is practicable provided, the calves have a separate calf pen.