Contrast-enhanced magnetic resonance angiography (CE-MRA) of intra- and extra-cranial vessels in dogs.

Until recently intra- and extra-cranial vessels in dogs have been imaged using conventional X-ray or digital subtraction angiography. As both of these methods are surgically demanding and involve the use of complex equipment with potential risks for the animal, they are now mainly used in experimental work. In this study, a method for delineating the intra- and extra-cranial vessels of dogs using contrast-enhanced magnetic resonance angiography (CE-MRA) has been examined. The MR images were acquired on a 1.5-T scanner after a bolus injection of gadolinium contrast medium. CE-MRA showed most of the major intra- and extra-cranial arteries and veins as well as most venous sinuses and plexuses of the brain. Difficulties may arise in differentiating between minor arterial and venous vessels as well as in the measurement of vessel diameter. More frequent use of this diagnostic method in clinical cases will indicate whether MRA of the head and brain is of as much use in veterinary medicine as it has become in human medicine. There is certainly potential value in detecting rare conditions in animals such as aneurysms and vascular malformations, as well as in examining vessels feeding intracranial masses and the investigation of cerebrovascular accidents.

[The results of caries prophylaxis after 25 years of the School Dental Clinic in the city of St. Gallen]. / Ergebnisse der Kariesprophylaxe nach 25 Jahren Schulzahnklinik in der Stadt St. Gallen.

Since 1966 the School Dental Clinic of St. Gall has been in charge of preventive dentistry and treatment of school and kindergarten children. For children from kindergarten and the 1st level of primary school, the caries incidence rate was established in percentages. For those of 14 years of age, the DFM-T index (including 2 bit-wings) was determined. For the 14-year-old children the average number of carious, filled and extracted teeth (DMF-teeth) decreased as follows: 1974 DFM-T = 7.0; 1978 DMF-T = 5.0; 1982 DMF-T = 3.0; 1987 DMF-T = 2.7; 1991 DMF-T = 1.1. The percentage of children with a healthy natural dentition in this age group was approximately 40% in 1991. The number of extractions of permanent teeth dropped 15 times, the number of required tooth fillings up to 5 times. Whilst children of 14 years of age in 1991 showed a minimum of carious lesions, the caries prevalence of kindergarten children and those of 1st level primary school increased slightly (partly due to influx of foreigners). This fact draws attention to the significance of a uniform, continuous and systematic prevention in the future.