Optimisation of contrast medium volume and injection-related factors in CT pulmonary angiography: 64-slice CT study.

OBJECTIVE: To compare the image quality of computed tomography pulmonary angiography (CTPA) obtained with the injection of various low doses of contrast medium (CM) with different injection-related factors. METHODS: A total of 90 patients (42 females, 48 males; 54.3 +/- 18.6 years) undergoing CTPA were included. Three CM protocols, each containing 30 patients, were created. Protocols 1, 2 and 3 consisted of a CM of 60 ml, 55 ml and 50 ml, and a bolus trigger level of 120 HU, 90 HU and 75 HU, respectively. Injection was uniphasic for protocols 1 and 2 (flow rate 5 ml/s), and biphasic for protocol 3 (flow rates 5 and 4 ml/s); with saline flushing afterwards. Enhancement was measured in three central and six peripheral pulmonary arteries. RESULTS: The mean attenuation value for pulmonary arteries was over 250 HU for all protocols. There was no difference between the attenuation levels with the protocols (p > 0.05). The percentage of pulmonary arteries exceeding optimal attenuation (> or =250 HU) showed that protocols 2 and 3 were 90-100% successful (p < 0.05). CONCLUSION: The use of proper injection-related factors during CTPA, such as a low trigger level and a high flow rate with saline injection following a decreased CM volume (55 ml or 50 ml), will enable adequate pulmonary artery contrast enhancement.

Pineal gland calcification, lumbar intervertebral disc degeneration and abdominal aorta calcifying atherosclerosis correlate in low back pain subjects: A cross-sectional observational CT study.

The goal of this cross-sectional observational study was to assess the possible impact of pineal gland calcification upon the intervertebral disc degeneration and abdominal aorta atherosclerosis in subjects with low back pain, and to investigate the course of these processes with aging. The study was carried out on 81 (66 women and 15 men) subjects: younger than 45 years (group X, n=22), 45-65 years of age (group Y, n=45), and older than 65 years (group Z, n=14). In addition to clinical data, computed tomography (CT) scan of the brain as well as X-ray and CT examination of the lumbar spine were recorded in this study. The degree of disc degeneration and calcification rates of aortic wall and pineal gland were independently determined by two radiologists. Both ratio of calcified pineal gland and density of pineal calcification increased progressively with aging. Also, both the degree of aortic wall calcification and disc degeneration score increased with advancing age. On CT scan, a positive correlation between degree of aortic wall calcification and disc degeneration score was found (r=0.306, p<0.01). Importantly, there was a positive association between calcification of the pineal gland and degenerative disc disease in X-ray or CT study (r=0.378 and r=0.295, p<0.005 and p<0.01, respectively), as well as between abdominal aorta atherosclerosis and pineal calcification (r=0.634, p<0.001). Our findings suggest that there is a significant interaction between pineal gland calcification and lumbar intervertebral disc degeneration and also abdominal aorta atherosclerosis. However, further studies with a larger subject cohorts are needed.

Age-related changes in the incidence of pineal gland calcification in Turkey: A prospective multicenter CT study.

The goal of this cross-sectional observational study was to determine the incidence of pineal gland calcification (PGC), to investigate the interaction of PGC and aging, and to compare the incidence of PGC among the populations living in Turkey. In a prospective study the rate of PGC on CT scans of 1376 individuals in six referral centers from different regions of Turkey was investigated, with emphasis on effects of climatological parameters and aging on PGC. It was found that the incidence of PGC increased rapidly after first decade and the increase remains gradual thereafter, higher in males than in females for all age groups. There was a significant difference for incidence and degree of PGC between different clinics and between both sexes (p<0.001). In addition, there was a significant difference for the degree of PGC between the clinics in low altitude group and those in high altitude group (p<0.001 for each). Logistic regression analysis revealed that age, sex, altitude and intensity of sunlight exposure significantly affected the risk of PGC (odds ratios (OR) 1.335, 95% confidence intervals (CI) 1.261-1.414, p<0.001; OR 1.900, 95% CI 1.486-2.428, p<0.001; OR 0.715, 95% CI 0.517-0.990, p<0.05; OR 0.997, 95% CI 0.994-0.999, p<0.01, respectively). Furthermore, by multiple linear regression analysis, high altitude and increased intensity of sunlight exposure were found to affect the degree of PGC (beta=0.003, p<0.001). It is concluded that there is a close relationship between PGC and the aforementioned parameters, supporting a link between the development of PGC and these. This study provides some reference data for new clinical studies on the putative role of pineal gland in future.