Contrast‐enhanced ultrasound using a time‐intensity curve for the diagnosis of renal cell carcinoma

Abstract

RESULTS• Pathological diagnoses were renal cell carcinoma in 30 patients.• The TTP of the cancer was shorter than that of the normal parenchyma in all cases (6.0 ± 2.0 vs 10.4 ± 3.0 s; P < 0.0001).• The Δ I did not differ between the cancer and normal parenchyma [21.3 ± 5.9 vs 20.9 ± 7.0 decibels (db); P = 0.68]; the Δ I/TTP of the cancer was significantly higher than that of the normal parenchyma (3.9 ± 1.4 vs 2.2 ± 0.94 db/s; P < 0.0001).• TIC patterns of solid cancer and cystic cancer were very similar. CONCLUSIONS• An objective and quantitative diagnosis of renal cell carcinoma by CEUS using a second-generation ultrasound contrast agent can be made by employing a TIC.• The TIC patterns of solid and cystic cancers were very similar, despite their morphological and vascular differences.• CEUS using TIC is a promising tool in the diagnosis of cystic renal cancer. KEYWORDScontrast-enhanced ultrasound, secondgeneration ultrasound contrast agent, timeintensity curve, renal cell carcinoma Study Type -Diagnosis (non-consecutive series) Level of Evidence 3bWhat's known on the subject? and What does the study add? In terms of imaging differentiation, distinguishing complex cystic renal masses that require surgery from those that do not remains a common and difficult diagnostic problem. Magnetic resonance imaging (MRI) is useful for characterizing complex cystic renal masses. But there are some cases that are difficult to diagnose differentially on computed tomography (CT) or MRI.We evaluated the usefulness of contrast-enhanced ultrasound (CEUS) for the diagnosis of cystic renal cell carcinoma by using a time-intensity curve (TIC). Assessments of blood flow in the solid component of a cystic tumour by CEUS using a second-generation US contrast agent and TIC analysis have made it easier to objectively diagnose cystic renal cancer. OBJECTIVE

Quantitative contrast-enhanced ultrasonography for the differential diagnosis of endometrial hyperplasia and endometrial neoplasms

“…The overall TIC displayed a quick rise-quick decline profile, with a short AT and PT, high EI, and short washout and clearance half-times. By contrast, the TIC of benign endometrial lesions increased slowly showing blunt peaks during the initial phase and declined slowly during the later phase (25). The overall curve had a slow rise-slow decline profile, with longer AT and PT, lower EI, and longer washout and clearance half-times, compared with the endometrial malignancy TIC.…”

Qualitative and Quantitative Analysis with Contrast-Enhanced Ultrasonography: Diagnosis Value in Hypoechoic Renal Angiomyolipoma

“…Though some imaging features are valuable in the diagnosis of minimal fat AML, such as homogeneous and prolonged enhancement on CECT (11), high T1-signal intensity ratio, low T2-signal intensity ratio and high arterial-to-delayed enhancement ratio on MRI (12), their application is limited by nephrotoxicity, high cost, and material implant. CEUS, is rarely used as a safe diagnostic modality to differentiate renal tumors, especially with quantitative analysis that is more objective, reliable and reproducible (13, 14, 15). We used both qualitative and quantitative analyses with CEUS to explore the features of hypoechoic/minimal fat AMLs.…”

Quantitative assessment of solid renal masses by contrast-enhanced ultrasound with time–intensity curves: how we do it

“…With CEUS, ccRCC enhances earlier and to a greater degree, than normal renal cortex [12,23,[35][36][37]. With regard to the TIC, this is manifested by a shorter RT and TTP, a steeper WIS, and a higher peak intensity, than normal renal cortex.…”

“…The optimal length of time to observe renal mass enhancement has not been established, but we obtain cines for at least 2 min, so that enhancement can be observed to well past nephrographic phase. From the cine, a time-intensity curve (TIC) can be created, from which quantitative perfusion parameters can be extracted [18,23,24].…”