Digital subtract angiography and lipiodol deposits following embolization in cirrhotic nodules of LIRADS category ≥3

Abstract

Purpose: To assess the correlation between Liver Imaging Reporting and Data System (LIRADS) and digital substract angiography (DSA) and lipiodol deposits in cirrhotic nodules of LIRADS category ≥3 receiving interventional treatment.

Methods: From June 2014 to June 2016, patients with cirrhotic nodules were identified retrospectively and MR images were reviewed by sub-specialty radiologists according to modified LIRADS v2014. Correlation between nodules of LIRADS category ≥3 and DSA findings and lipiodol deposits were analyzed.

Results: 71 cirrhotic nodules were evaluated in 33 patients. 39/71 nodules were classified as LR-3, 9/71 nodules were categorized as LR-4, 23/71 nodules were grouped into LR-5. 43 nodules presented positive DSA, 37 nodules showed presence of lipiodol deposits during follow up. With the upgrade of LIRADS category of cirrhotic nodules, DSA and lipiodol deposits became more conspicuous. Spearman analysis demonstrated positive correlations between LIRADS and DSA (r = 0.567, P = 0.000) as well as LIRADS and lipiodol deposits (r = 0.616, P = 0.000). ROC analysis revealed a cut-off value of LR ≥ 4 resulted in a sensitivity of 67.4% and specificity of 89.3% in predicting positive DSA (RUC = 0.799, P ＜ 0.0001), and a sensitivity of 75.7% and specificity of 88.2% in predicting lipiodol deposits (RUC = 0.818, P ＜ 0.0001). Of 39 lesions of LR-3, 64.1% (25/39) showed negative DSA, and 76.9% (30/39) showed absence of lipiodol deposits during follow up. Logistic regression analysis identified arterial enhancement (OR = 26.837, P = 0.002) and lesion size (OR = 1.325, P = 0.022) were independently associated with positive DSA in nodule of LIRADS category ≥3, while no factors were associated with lipiodol deposits.

Conclusion: The LIRADS can be used to predict DSA findings and lipiodol deposits in nodules with LIRADS score 3 and above. LIRADS 3 nodules tend to be DSA-negative and have less lipiodol deposits. DSA and lipiodol deposits become more conspicuous in nodules from LIRADS 3 to 5.

Keywords: BCLC, Barcelona Clinic Liver Cancer; DN, dysplastic nodules; DSA, digital subtract angiography; DWI, diffusion weighted imaging; Digital substract angiography; HCC, hepatocellular carcinoma; LIRADS, Liver Imaging Reporting and Data System; LR-M, probably or definitely malignant but not specific for HCC; Lipiodol deposits; Liver imaging reporting and data system; PACS, picture archiving and communication system; PWI, perfusion weighted imaging; RIS, radiology information system; RN, regenerative nodules; T1WI, T1 weighted imaging; T2WI, T2 weighted imaging; TACE, transcatheter arterial chemoembolization; TAE, transcatheter arterial embolization.

Graphical abstract

Fig. 1

Flowchart for selection of the patient in the present study.

Fig. 2

LR-3 nodule and TAE outcome. An obscure nodule in segment 8 showed iso intensity on T1WI (A)and mild hyper intensity on T2WI (B), T1-weighted post-contrast demonstrated iso-enhancing relative to liver (C, D). This nodule was categorized in LR-3. DSA findings was negative (E), diagnostic and prophylactic embolization was merely performed. CT 6 weeks later showed absence of lipiodoldeposits (F).

Fig. 3

LR-4 nodule and TACE outcome. An “index nodule” between segment 5 and 8 was noted in a cirrhosis patient, which showed T1 hypointense (A). Arterial phase of enhancement showed centric foci of enhancement (B). The nodule washed out on portal venous phase (C). This nodule was grouped into LR-4. DSA showed abnormality of hepatic arteries (E), which favors a diagnosis of HCC. 11 months later, CT showed a “dot” high intensity which was lipiodol in the lesion (F).

Fig. 4

LR-5 nodule and TACE outcome. T1-weighted (A) and T1-weighted post-contrast arterial phase (B, C, D) MRI showed a nodular external contour of the liver in segment 7 with hypervascularity on DSA (E), representing hepatocellular carcinoma. 2 months later, dispersed lipiodoldeposits were noted (F).

Fig. 5

Using LIRADS category to predict DSA findings. With a cut-off of LR ≥ 4, the sensitivity to predict DSA positivity was 67.4% and the specificity was 89.3%, RUC = 0.799 [95%CI 0.687-0.885], P ＜ 0.0001.

Fig. 6

Using LIRADS category to predict lipiodoldeposits. The threshold of LR ≥ 4 resulted in a 75.7% sensitivity and a 88.2% specificity in predicting lipiodoldeposits, RUC = 0.818[95%CI 0.768-0.940], P ＜ 0.0001.