Abstract:
:Contrast-enhanced ultrasound (US) imaging is potentially applicable to the investigation of vascular disorders of the testis. We investigated the ability of two automated computer algorithms to analyse contrast-enhanced pulse inversion US data in a rabbit model of unilateral testicular ischaemia and to correctly determine relative testicular perfusion: nonlinear curve fitting of the US backscatter intensity as a function of time; and spectral analysis of the intensity time trace. We compared (i) five metrics based on the algorithmic data to testicular perfusion ratios obtained with radiolabelled microspheres, a reference standard; (ii) qualitative assessment of the US images by two independent readers blinded to the side of the experimental and control testes to the radiolabelled microsphere perfusion ratios; and (iii) results of the algorithmically-derived metrics to the qualitative assessments of the two readers. For the curve fit method, the algorithmically-derived metrics agreed with the reference standard in 54% to 68% of all cases. For the spectral method, the results agreed in 70% of all cases. The two readers agreed with the reference standard in 40% and 35% of all cases, respectively. These results suggest that automated methods of analysis may provide useful information in the assessment of testicular perfusion.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Thierman JS,Clement GT,Kalish LA,O'Kane PL,Frauscher F,Paltiel HJdoi
10.1088/0031-9155/51/14/010subject
Has Abstractpub_date
2006-07-21 00:00:00pages
3419-32issue
14eissn
0031-9155issn
1361-6560pii
S0031-9155(06)16314-9journal_volume
51pub_type
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