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Anke Thomas

Publications and source records attributed to Anke Thomas.

At least 19 recordsLinked to original sources
PubMed2006

Improved diagnosis of early kidney allograft dysfunction by ultrasound with echo enhancer--a new method for the diagnosis of renal perfusion.

BACKGROUND: Conventional ultrasound parameters such as the resistance index (RI) are only of limited use in the diagnosis of early allograft dysfunction. We, therefore, performed a prospective study to compare the value of ultrasound contrast media (USCM) with conventional US in the diagnosis of early allograft dysfunction. METHODS: A total of 48 consecutive kidney recipients underwent US examination after USCM administration 4-10 days after transplantation. Arterial inflow was determined in the interlobar artery and renal cortex using time-intensity curve (TIC) software. The difference in time-to-peak intensity between these two vascular territories was determined, and a perfusion quotient (PQ) was defined as the ratio of TIC increase of interlobar artery to renal cortex. Three patients with segmental loss of renal perfusion demonstrated by Doppler US were excluded. RESULTS: Nineteen patients had an uneventful clinical course (control group); PQ was 1.2 +/- 0.4. Seven patients with a large perirenal haematoma, without rejection had an increased PQ (P < 0.05) and a prolonged time difference (P < 0.05). Based on clinical and histological criteria, the remaining patients were classified as acute tubular necrosis (ATN) (n = 7), non-vascular rejection (n = 7) or vascular rejection (n = 5). RI determination could not discriminate these groups. Patients with ATN (PQ = 1.6 +/- 0.7) or non-vascular rejection (PQ = 1.1 +/- 0.6) had a lower PQ than patients with vascular rejection (PQ = 2.2 +/- 0.8, P < 0.05). The time difference in all three subgroups was longer compared with controls. CONCLUSIONS: USCM might be superior in the diagnosis of early kidney allograft dysfunction compared with conventional US by means of RI determination. Perirenal haematoma, ATN and vascular rejection are associated with characteristic changes of the TIC.

Adolescent↗
PubMed2006

Real-time sonoelastography performed in addition to B-mode ultrasound and mammography: improved differentiation of breast lesions?

RATIONALE AND OBJECTIVES: The goal of the present study was to compare the sensitivity and specificity of elastography with that of B-mode ultrasound (US) and mammography. MATERIALS AND METHODS: A total of 300 patients with histologically confirmed breast lesions (168 benign, 132 malignant) were included. Evaluation was by means of the three-dimensional finite-element method. The data are color-coded and superimposed on the B-mode US scan. The images were evaluated by two independent readers. The results were compared with mammography, histology, and the data obtained by previous US investigations. Sensitivities and specificities were calculated. RESULTS: Sensitivity and specificity in the differentiation of benign and malignant lesions were 87% and 85%, respectively, for mammography and 94% and 83% for B-mode US. The two examiners were in very good agreement in their evaluation of the elastograms (kappa: 0.86). Elastography had a sensitivity of 82% and a specificity of 87%. Elastography was superior to B-mode US in diagnosing Breast Imaging Reporting and Data System (BI-RADS) 3 lesions (92% vs. 82% specificity) and in lipomatous involution (80% vs. 69% specificity). CONCLUSION: Elastography in breast lesions showed a higher specificity and a lower sensitivity in comparison with B-mode sonography. Elastography may be beneficial in BI-RADS 3 lesions and in lipomatous involution.

Adolescent↗