Performance of single-use syringe versus multi-use MR contrast injectors: a prospective comparative study.

The goal of this study was to compare performance parameters of a single-use syringe and a multi-use MR contrast injector. We compared preparation time, cost for disposables and volumes of contrast material used for a single-use (SI) and a multi-use (MI) MR contrast injector in a prospective cross-over trial. During the first study period all consecutive patients eligible for dynamic MR on two systems were included during a period of 20 working days. After 10 days, the injector was switched. Radiographer satisfaction was evaluated using a questionnaire. Contrast usage and waste on system MI was optimised by extra instructions for our radiographers and measured during the second study period of 10 consecutive working days. A total of 202 and 163 patients for systems SI and MI were included, respectively. Average preparation time was 4:55 min for SI and 2:24 min for MI (p < 0.05). Contrast waste for SI was 13% using 7.5 ml syringes. Contrast waste for MI was 5% for 7.5 ml containers. Costs for disposables were lower for MI if more than 5 patients per day were injected. Radiographer satisfaction was higher for MI (4.7 versus 2.8 on a 5-point scale; p < 0.05). The multi-use MR contrast injector led to higher radiographer satisfaction, shorter preparation time, and lower cost if more than 5 patients were injected per day. In addition, cheaper contrast containers of 15 or 30 ml could be used for the first patients if more than 2 or more than 4 injections are performed per day, potentially leading to lower contrast waste.

Familial hypercholesterolaemia in patients with ischaemic stroke or transient ischaemic attack.

BACKGROUND AND PURPOSE: Identification of patients with familial hypercholesterolaemia (FH) is a prerequisite for the appropriate management of their excess cardiovascular risk. It is currently unknown how many patients with acute ischaemic stroke or transient ischaemic attack (TIA) are affected by FH and whether systematic screening for FH is warranted in these patients. METHODS: The prevalence of a clinical diagnosis of FH was estimated in a large representative series of patients with acute ischaemic stroke or TIA (ABCD2 score ≥ 3) using the Dutch Lipid Clinic Network Algorithm (DLCNA; possible FH ≥3, probable/definite FH ≥6). RESULTS: Out of 1054 patients included in the present analysis, 14 had probable/definite FH (1.3%; 95% confidence interval 0.6-2.0) and 107 possible FH (10.2%; 8.4-12.0) corresponding to an overall prevalence of potential FH of 11.5%. Prevalences were even higher in patients with stroke/TIA manifestation before age 55 in men or 60 in women (3.1%, 0.6-5.6; and 13.1%, 8.3-17.9) and those with a prior history of cardiovascular disease (2.6%, 0.9-4.3; and 15.1%, 11.3-18.9). Of note, in two-thirds of our patients with probable/definite and possible FH, stroke or TIA was the initial clinical disease manifestation. CONCLUSIONS: The frequency of potential FH, based on clinical criteria, in patients with acute ischaemic stroke or TIA was 11.5% and that of probable/definite FH (1.3%) was similar to recently reported counts for patients with acute coronary syndrome (1.6%). FH screening using the DLCNA is feasible in clinical routine and should be considered as part of the usual diagnostic work-up.

ProPSA and the Prostate Health Index as predictive markers for aggressiveness in low-risk prostate cancer-results from an international multicenter study.

BACKGROUND: One of the major challenges in prostate cancer (PCa) treatment is distinguishing insignificant PCa from those forms that need active treatment. We evaluated the impact of PSA isoforms on risk stratification in patients with low-risk PCa as well as in active surveillance (AS) candidates who underwent radical prostatectomy. METHODS: A total of 112 patients with biopsy confirmed Gleason score (GS) 6 PCa of four different international institutions were prospectively enrolled in the study. Blood withdrawal was performed the day before radical prostatectomy. In addition, patients were classified according to the EAU and NCCN criteria for AS candidates. PSA, free PSA (fPSA) and proPSA were measured using dual monoclonal antibody sandwich immunoassays. In addition, the Prostate Health Index (PHI=proPSA/fPSA × âˆšPSA) was calculated. Final histology of the radical prostatectomy specimens was correlated to PSA, its isoforms and PHI. RESULTS: Serum proPSA levels were significantly elevated in those patients with an upgrade in final histology (GS⩾7). In addition, higher proPSA levels were predictive for extraprostatic extension (⩾pT3a) as well as for positive surgical margins. Interestingly, PHI had an even higher predictive power when compared with proPSA alone concerning GS upgrading, extraprostatic extension and surgical margins in both the total and the AS patient group. CONCLUSION: We showed in a multicenter study that proPSA is a valuable biomarker to detect patients with aggressive PCa in a cohort of GS 6 patients, who would benefit from active tumor therapy. Combining proPSA with the standard markers PSA and fPSA using PHI further increases the predictive accuracy significantly. Moreover, our data support the use of PHI for monitoring PCa patients under AS.

Computed tomography pulmonary angiography in acute pulmonary embolism: the effect of a computer-assisted detection prototype used as a concurrent reader.

PURPOSE: To assess the effect of computer-assisted detection (CAD) on diagnostic accuracy, reader confidence, and reading time when used as a concurrent reader for the detection of acute pulmonary embolism in computed tomography pulmonary angiography. MATERIALS AND METHODS: In this institutional review board-approved retrospective study, 6 observers with varying experience evaluated 158 negative and 38 positive consecutive computed tomography pulmonary angiographies (mean patient age 60 y; 115 women) without and with CAD as a concurrent reader. Readers were asked to determine the presence of pulmonary embolism, assess their diagnostic confidence using a 5-point scale, and document their reading time. Results were compared with an independent standard established by 2 readers, and a third chest radiologist was consulted in case of discordant findings. RESULTS: Using logistic regression for repeated measurements, we found a significant increase in readers' sensitivity (P<0.001) without loss of specificity (P=0.855) with the effects being reader dependent (P<0.001). Sensitivities varied from 68% to 100% without CAD and from 76% to 100% with CAD. A 2-way analysis of variance showed a small but significant decrease in reading time (P<0.001), with the duration varying between 24 and 208 seconds without CAD and between 17 and 196 seconds with CAD, and a significant increase in readers' confidence scores using CAD as a concurrent reader (P<0.001). CONCLUSIONS: CAD as a concurrent reader has the potential to increase readers' sensitivity and confidence with a decrease in reading time without loss of specificity. The differences between readers, however, require further evaluation of CAD as a concurrent reader in a larger trial before stronger conclusions can be drawn.

Renal function and plasma volume following ultramarathon cycling.

In recreational cyclists marathon cycling influences renal function only on a minimal scale. Respective information on extreme ultramarathon cycling in better trained athletes is not available. The objective was to evaluate the renal and haematological effects of ultraendurance cycling in the world's best ultramarathon cyclists. Creatinine (CR), urea, haemoglobin (Hb), haematocrit (Hct) and plasma volume (PV) were investigated in 16 male ultramarathon cyclists during the 1st Race Across the Alps in 2001 (distance: 525 km; cumulative altitude difference: 12,600 m). All renal functional parameters were normal pre-exercise. During the race serum CR, urea and uric acid rose significantly by 33, 97 % and 18 % (p <0.001 respectively) and nearly normalised again on the following day. The decline in calculated CR clearance was 25 %. There was a negative correlation (r=- 0.575, p=0.02) between the rise in serum CR and the athlete's training kilometers. The serum urea/CR ratio rose above 40 in 12 athletes (75 %). Mean fractional sodium excretion and fractional uric acid excretion fell below 0.5 % (p <0.001) and 7 %, indicating reduced renal perfusion. The deflection of the renal functional parameters was temporary and nearly gone after 24 hours of recovery. Hct declined during the race from 0.44 to 0.42, and continued falling on the next day (0.42 --> 0.40; p <0.001). The corresponding rises in calculated PV were + 8 % and + 22 %. The study affirms that in world class cyclists the enormous strains of ultramarathon cycling influence renal function only on a minimal scale. The impact on the PV, however, is pronounced leading to marked haemodilution post-exercise. This very temporary "impairment of renal function" seems to be the physiological response to ultramarathon cycling and may be attenuated to some extent by preceding high-volume training.