HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Raman, S. S. Articles by Lassman, C. Search for Related Content PubMed PubMed Citation Articles by Raman, S. S. Articles by Lassman, C. Social Bookmarking                      What's this? Hotlight (NEW!) What's Hotlight?

Creation of Radiofrequency Lesions in a Porcine Model

Correlation with Sonography, CT, and Histopathology

¹ Department of Radiological Sciences, UCLA School of Medicine, 10833 LeConte Ave., Los Angeles, CA 90095-1721.
² Department of Pathology, UCLA School of Medicine, Los Angeles, CA 90095-1721.

View larger version (115K): [in a new window]   Fig. 1. —Photograph of LeVeen electrode (Radiotherapeutics, Mountain View, CA). Note eight retractable, distal curved hooks that deploy and expand to form umbrella shape with radial diameter of 2 cm.

View larger version (107K): [in a new window]   Fig. 2A. —Sonographic appearance of radiofrequency lesion. Initial oblique sagittal sonogram obtained through plane of radiofrequency probe (straight arrows) reveals deployed distal curved hooks (curved arrows) in normal liver parenchyma.

View larger version (109K): [in a new window]   Fig. 2B. —Sonographic appearance of radiofrequency lesion. Sonogram obtained during ablation but just before termination shows echogenic cloud (arrows) that developed centrally and increased in size.

View larger version (124K): [in a new window]   Fig. 2C. —Sonographic appearance of radiofrequency lesion. Early sonogram obtained after ablation (within 2 min) shows echogenic cloud that begins to rapidly dissipate leaving hypoechoic rim (arrows).

View larger version (121K): [in a new window]   Fig. 2D. —Sonographic appearance of radiofrequency lesion. Late sonogram obtained after ablation (between 2 and 5 min) shows radiofrequency lesion that is primarily hypoechoic (arrows), more distinct, and larger in size than in C. Note residual central echogenicity.

View larger version (106K): [in a new window]   Fig. 3A. —Various sonographic appearances of radiofrequency lesions. Early (within 2 min) sonogram obtained after ablation shows echogenic cloud (arrows).

View larger version (102K): [in a new window]   Fig. 3B. —Various sonographic appearances of radiofrequency lesions. Late (2-5 min) sonogram shows fading echogenic cloud centrally within larger hypoechoic lesion that is demarcated by thin hyperechoic rim (arrows).

View larger version (123K): [in a new window]   Fig. 4A. —CT scans obtained 24 hr after ablation of radiofrequency lesion (same lesion as shown in Fig. 2A,2B,2C,2D). Initial unenhanced CT scan shows hypodense lesion (arrowheads) with variable hyperdensity centrally indicating possible hemorrhage. Note how second lesion (curved arrow), located medially, is partially imaged only.

View larger version (141K): [in a new window]   Fig. 4B. —CT scans obtained 24 hr after ablation of radiofrequency lesion (same lesion as shown in Fig. 2A,2B,2C,2D). Contrast-enhanced arterial (B) and portal venous (C) phase CT scans show variable hyperemic rim (straight arrows) surrounding hypodense, nonenhancing core (arrowheads). Note how second lesion (curved arrow), located medially, is partially imaged only.

View larger version (152K): [in a new window]   Fig. 4C. —CT scans obtained 24 hr after ablation of radiofrequency lesion (same lesion as shown in Fig. 2A,2B,2C,2D). Contrast-enhanced arterial (B) and portal venous (C) phase CT scans show variable hyperemic rim (straight arrows) surrounding hypodense, nonenhancing core (arrowheads). Note how second lesion (curved arrow), located medially, is partially imaged only.

View larger version (138K): [in a new window]   Fig. 5. —Gross pathology of representative radiofrequency lesion. Between 24 and 48 hr after ablation, the typical radiofrequency lesion is delimited by three concentric areas: central core that is pale or tan (N), middle hemorrhagic or red rim (arrowheads), and outer pink rim (arrows) of variable thickness that merges with normal hepatic parenchyma (L).

View larger version (120K): [in a new window]   Fig. 6. —Low-power photomicrograph of representative radiofrequency lesion (same lesion as shown in Figure 5) shows three zones: inner necrotic pale zone (N) that contained dead, empty vacuolated hepatocytes on highpower microscopy; red rim (H) that contained hemorrhagic material and thrombosed vessels without any viable cells; and outer pink rim (P) that contained an admixture of hemorrhage and viable hepatocytes. These zones corresponded to zones visible on Figure 5. Normal liver (L) surrounds radiofrequency lesion.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati