Construction of the auxiliary elements and angular measurements in sidewall and bifurcation aneurysms.

<p>Inflow angle α was determined by the aneurysm neck section line and the centerline of the afferent vessel close to the aneurysm. The angle close to the aneurysm neck (δ₁) and more remote from the aneurysm neck (δ₂) were determined by centerlines of the efferent and afferent vessel close (δ₁), respectively, located more remotely from the aneurysm neck (δ₂).</p

Slight yet not significant increase of the vessel diameter after stenting.

<p>Change in vessel diameter of afferent and efferent vessel pre- and posttreatment, n = 18 for the presenting group and n = 30 for the poststenting group (graphs shows mean ± SEM) (A). DSA-angiography of a 43-year old patient with MCA aneurysm showing an increase in diameter especially of the efferent vessel 11 months after SACE (B).</p

Aneurysm-vessel complex in ruptured aneurysms compared to unruptured aneurysms.

<p>Angle of unruptered (α: n = 24, δ₁: n = 24 and δ₂: n = 19) and ruptured aneurysms (n = 13) before treatment (graph shows mean ± SEM, *: P ≤ .05), (A). Vessel size of unruptured (n = 13) and ruptured aneurysms (n = 5) (B).</p

Inverse relationship between the angular change and the pretreatment angle (α, δ₁ and δ₂).

<p>α: n = 37, r = -0.26, P = 0.14 (A), δ₁: n = 37, r = -0.41, P ≤ .05 (B) and δ₂: n = 32, r = -0.47, P ≤ .01 (C), x axis, angle α, δ₁ or δ₂ before treatment, y axis, angular difference between pre- and posttreatment.</p

Angle α, δ₁ and δ₂ before and after stent-assisted coiling.

<p>Angle α, δ₁ and δ₂ before and after stent-assisted coiling.</p

Micro-CT vs. Whole Body Multirow Detector CT for Analysing Bone Regeneration in an Animal Model

<div><p>Objectives</p><p>Compared with multirow detector CT (MDCT), specimen (ex vivo) micro-CT (μCT) has a significantly higher (~ 30 x) spatial resolution and is considered the gold standard for assessing bone above the cellular level. However, it is expensive and time-consuming, and when applied in vivo, the radiation dose accumulates considerably. The aim of this study was to examine whether the lower resolution of the widely used MDCT is sufficient to qualitatively and quantitatively evaluate bone regeneration in rats.</p><p>Methods</p><p>Forty critical-size defects (5mm) were placed in the mandibular angle of rats and covered with coated bioactive titanium implants to promote bone healing. Five time points were selected (7, 14, 28, 56 and 112 days). μCT and MDCT were used to evaluate the defect region to determine the bone volume (BV), tissue mineral density (TMD) and bone mineral content (BMC).</p><p>Results</p><p>MDCT constantly achieved higher BV values than μCT (10.73±7.84 mm³ vs. 6.62±4.96 mm³, p<0.0001) and consistently lower TMD values (547.68±163.83 mm³ vs. 876.18±121.21 mm³, p<0.0001). No relevant difference was obtained for BMC (6.48±5.71 mm³ vs. 6.15±5.21 mm³, p = 0.40). BV and BMC showed very strong correlations between both methods, whereas TMD was only moderately correlated (r = 0.87, r = 0.90, r = 0.68, p < 0.0001).</p><p>Conclusions</p><p>Due to partial volume effects, MDCT overestimated BV and underestimated TMD but accurately determined BMC, even in small volumes, compared with μCT. Therefore, if bone quantity is a sufficient end point, a considerable number of animals and costs can be saved, and compared with in vivo μCT, the required dose of radiation can be reduced.</p></div

Mean values and differences between the MDCT-based and μCT-based parameters within the former CSDs, as well as the corresponding p-values of the t-test and Pearson’s correlation coefficients.

<p>Mean values and differences between the MDCT-based and μCT-based parameters within the former CSDs, as well as the corresponding p-values of the t-test and Pearson’s correlation coefficients.</p

A shows the significantly higher BV values obtained with MDCT compared with μCT, whereas B shows the significantly lower TMD values obtained.

<p>The BMC values matched well between μCT and MDCT (C, p = 0.05). The data represent means ± SDs; the notation * indicates significance at p < 0.0001 between the modalities.</p

Study setup indicating the time points for death and the corresponding numbers of specimens.

<p>Study setup indicating the time points for death and the corresponding numbers of specimens.</p

Scatterplots with a regression line, correlation coefficient (r), and estimated regression model showing the associations for BV (A), TMD (B) and BMC (C) obtained via μCT and MDCT (p < 0.0001).

<p>Scatterplots with a regression line, correlation coefficient (r), and estimated regression model showing the associations for BV (A), TMD (B) and BMC (C) obtained via μCT and MDCT (p < 0.0001).</p