Clinical and Imaging Follow-Up of Patients with Coiled Basilar Tip Aneurysms Up to 20 Years.

BACKGROUND AND PURPOSE: Long-term follow-up data of coiled basilar tip aneurysms are scarce, and little is known about the risk of late aneurysm-related adverse events. We followed a cohort of 154 patients with basilar tip aneurysms coiled between 1995 and 2006. MATERIALS AND METHODS: Imaging and clinical data were retrospectively reviewed. The incidence and timing of retreatment, rebleeds, and progressive mass effect by continuous aneurysm growth were recorded. Risk factors for retreatment were assessed. RESULTS: Clinical follow-up of 144 of 154 patients who survived the admission period was a mean of 9.8 years (median, 10.2; range, 0.3-20.1 years). During this period, 37 basilar tip aneurysms (26%) were additionally coiled (annual incidence rate, 2.6%; 95% CI, 1.8%-3.6%). Aneurysm size of >15 mm was the most important independent predictor for retreatment (OR, 8.7; 95% CI, 3.4-22.5). The first additional coiling was performed in the first year of follow-up in 17 of 37 patients (46%) and in 20 patients (54%) at a later time up to 17.2 years. Nine rebleeds occurred in 9 of 106 patients who initially presented with SAH after a median follow-up of 8.3 years (range, 0.3-16.6 years). The annual incidence rate was 0.7% (95% CI, 0.4%-1.5%). Eight patients died of aneurysm-related adverse events: 3 of rebleed and 5 of progressive mass effect. CONCLUSIONS: Retreatment of coiled basilar tip aneurysms was frequently needed during follow-up, also at long intervals. Most late mortality was from progressive mass effect, not from rebleeds. Life-long MRA follow-up at yearly intervals is recommended.

Offspring fitness in relation to population size and genetic variation in the rare perennial plant species Gentiana pneumonanthe (Gentianaceae).

Seeds were sampled from 19 populations of the rare Gentiana pneumonanthe, ranging in size from 5 to more than 50,000 flowering plants. An analysis was made of variation in a number of life-history characters in relation to population size and offspring heterozygosity (based on seven polymorphic isozyme loci). Life-his-tory characters included seed weight, germination rate, proportion of seeds germinating, seedling mortality, seedling weight, adult weight, flower production per plant and proportion of plants flowering per family. Principal component analysis (PCA) reduced the dataset to three main fitness components. The first component was highly correlated with adult weight and flowering performance, the second with germination performance and the third component with seed and seedling weight and seedling mortality. The latter two components were considered as being maternally influenced, since these comprised life-history traits that were significantly correlated with seed weight. Multiple regression analysis showed that variation in the first fitness component was mainly associated with heterozygosity and not with population size, while the third fitness component was only correlated with population size and not with heterozygosity. The latter relationship appeared to be non-linear, which suggests a stronger loss of fitness in the smallest populations. The second (germination) component was neither correlated with population size nor with genetic variation. There was only a weak association between population size, heterozygosity and the population coefficients of variation for each life history character. Most correlation coefficients were negative, however, which suggests that there is more variation among progeny from smaller populations. We conclude that progeny from small populations of Gentiana pneumonanthe show reduced fitness and may be phenotypically more variable. One of the possible causes of the loss of fitness is a combination of unfavourable environmental circumstances for maternal plants in small populations and increased inbreeding. The higher phenotypic variation in small populations may also be a result of inbreeding, which can lead to deviation of individuals from the average phenotype through a loss of developmental stability.