Aortic valve stenosis: non-invasive preoperative evaluation using 64-slice CT angiography.

AIM: In patients affected by aortic valve stenosis (AS) it is mandatory to rule out coronary artery disease (CAD). The role of retrospectively ECG-gated 64-slice CT angiography (64-SCTA) was assessed in patients with AS referred for surgical valve replacement. METHODS: Forty-two patients with AS underwent ECG-gated 64-SCTA of thoracic aorta, including the heart and coronary arteries, before surgical valve replacement. Images were evaluated by two independent readers and compared with surgical findings in terms of aortic valve calcification grading, valvular morphology, aortic valve annulus and sino-tubular junction diameters, and valvular area planimetry. Quantitative evaluation of cusps opening was also performed. Finally, the presence of CAD, thoracic aortic aneurysm and left ventricle hypertrophy were assessed. RESULTS: Visualization of the aortic valve without motion artefacts was possible in 38 patients (90.5%). Valvular morphology was correctly assessed in all cases (100%). 64-SCTA correctly determined aortic valve calcification grading and the aortic valve annulus and sinotubular junction diameters in 100% of cases. The aortic valve planimetric area was assessed in 38 cases (90.5%). Ascending aortic aneurysms requiring surgical replacement were detected in 12 patients (28.6%). Significant left ventricle hypertrophy was found in 30 patients (71%). CONCLUSION: Preoperative evaluation of patients undergoing surgical replacement for AS with 64-SCTA is feasible. 64-SCTA can rule out CAD and evaluate the status of the aortic valve and thoracic aorta in the same examination, obtaining relevant information for surgical planning.

Densitometric kneecap changes after unilateral knee arthroplasty.

PURPOSE: To assess bone density of kneecaps in subjects with femoro-tibial prosthesis before and after surgery by means of DEXA examination. SUBJECTS AND METHODS: We examined 34 patients with unilateral femoro-tibial prosthesis, 20 healthy subjects of the same age and non-carriers of knee replacement and 14 healthy young adult subjects. All the data sets were analysed by two radiologists (AS and AM). The coincidence of the results between the two specialists was evaluated by means of Cohen's Kappa index and the results were considered statistically significative if p value is < of 0.05. RESULTS: The values of patellar BMD in the group of 34 patients, were: a minimum of 0.386 g/cm(2) (K = 0.879, p = 0.0012), a maximum 1.707 g/cm(2) (K = 0.886, p = 0.0016). The comparison between the left and right knee showed the following data: minimum difference 0.034 g/cm2 (K = 0.901, p = 0.0015), maximum difference of 0.622 g/cm(2) (K = 0.908, p = 0.0017), the average was found to be of 0.277 g/cm(2) (K = 0.894, p = 0.0018). But this difference tends to decrease 6 months after surgery. In the group of healthy young adults, we obtained the following values: a minimum of 0.782 g/cm(2) (K = 0.907, p = 0.0025), maximum 1.503 g/cm(2) (K = 0.932, p = 0.0012). Between both knees, the difference was minimal 0.006 g/cm(2) (K = 0.951, p = 0.0035) and maximum 0.096 g/cm(2) (K = 0.926, p = 0.0007) with an average difference of 0.058 g/cm(2) (K = 0.954, p = 0.0026). In the group of healthy subjects of the same age and non-carriers of knee replacement the values were average higher. A maximum value of 1.134 g/cm(2) (K = 0.894, p = 0.0028) and a minimum value of 0.944 g/cm(2) (K = 0.892, p = 0.0023) were found; between both knees a minimum difference of 0.010 g/cm(2) (K = 0.918, p = 0.0047) and a maximum of 0.090 g/cm(2) (K = 0.937, p = 0.0017) were found, with an average difference of 0.052 g/cm(2) (K = 0.956, p = 0.0024). CONCLUSIONS: DEXA examination of the patellar is recommended as a supplementary study to the clinical and radiological standard exams because it is able to provide additional information to determine when to intervene surgically, on the basis of patellar bone density values.