Transarterial chemoembolization of hepatocellular carcinoma: Can intraprocedural DYNA computed tomography serve as a guiding tool for the interventionist?

Manzoor Hussain; Tahleel Shera; Omair Ashraf Shah; Naseer Choh; Feroze Shaheen; Tariq Gojwari; Gull Mohammad Bhat; GM Gulzar

doi:10.4103/jcrsm.jcrsm_19_21

ORIGINAL ARTICLE

Year : 2021 | Volume : 7 | Issue : 2 | Page : 62-69

Transarterial chemoembolization of hepatocellular carcinoma: Can intraprocedural DYNA computed tomography serve as a guiding tool for the interventionist?

Manzoor Hussain¹, Tahleel Shera¹, Omair Ashraf Shah¹, Naseer Choh¹, Feroze Shaheen¹, Tariq Gojwari¹, Gull Mohammad Bhat², GM Gulzar³
¹ Department of Radiology, SKIMS, Srinagar, Jammu and Kashmir, India
² Department of Medical Oncology, SKIMS, Srinagar, Jammu and Kashmir, India
³ Department of Gastroenterology, SKIMS, Srinagar, Jammu and Kashmir, India

Date of Submission	28-Mar-2021
Date of Acceptance	25-Aug-2021
Date of Web Publication	30-Dec-2021

Correspondence Address:
Omair Ashraf Shah
Senior resident, Department of Radiology, SKIMS, Soura Address- 167 Nursingh Garh, Karanagar, Srinagar, J&K
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/jcrsm.jcrsm_19_21

Abstract

Aims And Objectives: We evaluated the role of Dyna CT in localizing HCC lesions and their selective vascular supply to help guide chemoembolization. We also evaluated the role of Dyna CT in assessing drug deposition within the lesion and predict the need of further drug delivery.
Methods: 24 patients with documented HCC were taken up for TACE after a pre-procedural contrast CT and MRI. An intra-procedural Dyna CT was done in all patients to obtain a three dimensional overview of the vascular network. Selective cannulation of the tumor arteries was achieved using a combined digital subtraction angiography and Dyna CT image guidance. Additional lesions and vessels identified on Dyna CT were also treated. Drug deposition within the lesion marking technical success was assessed on completion Dyna CT and the need for additional drug delivery was assessed.
Results: Contrast CT identified 36 lesions, DSA 33 lesions and Dyna CT 39 lesions in 24 patients. Dyna CT was the most sensitive for lesions <10 mm (p=0.006). Dyna CT identified 4 additional supplying lesion supplying arteries (2 hepatic, 2 extra hepatic) compared to DSA. In 6(25%) patients DYNA CT helped in improvement in catheter position in the form of more selective catheterization. 35 (90%) lesions showed homogenous Type 1 deposition, two lesions (5%) showed Type 2 and the other two (5%) showed type 3 deposition of lipoidol on completion Dyna CT. The latter two were further treated to achieve type 1 deposition and 100% technical success.
Conclusion: Dyna CT can effectively guide TACE procedure by not only identifying the lesions and their vascular supply but also helping in guiding the catheter for selective cannulation and drug deposition. Completion Dyna CT can effectively assess drug deposition and the need for additional treatment in the same setting if needed.

Keywords: DYNA computed tomography, hepatocellular carcinoma, magnetic resonance imaging, noncontrast computed tomography, transarterial chemoembolization

How to cite this article:
Hussain M, Shera T, Shah OA, Choh N, Shaheen F, Gojwari T, Bhat GM, Gulzar G M. Transarterial chemoembolization of hepatocellular carcinoma: Can intraprocedural DYNA computed tomography serve as a guiding tool for the interventionist?. J Curr Res Sci Med 2021;7:62-9

How to cite this URL:
Hussain M, Shera T, Shah OA, Choh N, Shaheen F, Gojwari T, Bhat GM, Gulzar G M. Transarterial chemoembolization of hepatocellular carcinoma: Can intraprocedural DYNA computed tomography serve as a guiding tool for the interventionist?. J Curr Res Sci Med [serial online] 2021 [cited 2023 May 30];7:62-9. Available from: https://www.jcrsmed.org/text.asp?2021/7/2/62/334449

Introduction

Hepatocellular carcinoma (HCC) is the fifth most common tumor in the world.^[1] Cirrhosis is the most important clinical risk factor for HCC with approximately 80% of cases of HCC developing in cirrhotic livers.^[2] The prognosis of HCC depends largely on the stage at which the tumor is detected with symptomatic patients having a dismal prognosis, while patients in whom HCC is detected at an early stage may benefit from curative and palliative treatments.^[3] Local therapies have been widely used in the recent past and include lipiodol-based transhepatic arterial chemoembolization (TACE) which can bide time for those listed for transplantation by delaying tumor progression and also increase survival in those not candidates for transplantation.^[4],[5] Chemotherapeutic agents used in TACE are prepared as emulsion to improve the preferential uptake and persistent deposition of the anticancer agents in the target tumors.^[6] Drug delivery to the lesion can be evaluated by the degree of iodized oil deposition which can in turn predict therapeutic response.^[7],[8] Although fluoroscopic imaging can help assess drug deposition, it is not sensitive and provides only indirect signs of drug deposition.^[7] A direct assessment of drug deposition can be done using a noncontrast computed tomography (NCCT) of the liver; however, this requires shifting the patient to the CT unit with the risks of contamination and difficult logistics, especially when the CT and angiographic units are distant from each other.^[8] This difficulty has been overcome in the recent past with the use of an angiographic system capable of acquiring both angiographic images as well as multi sectional soft-tissue images (DYNA CT) similar to NCCT. In addition to assessing the iodized oil deposition during the TACE procedure, this system can also be used to obtain three-dimensional angiographic views of the abdominal vessels, which can help in selective cannulation of vessels as well as identify additional lesions and additional supplying arteries. This modality is now being widely used as an alternative to conventional CT.^{[9],[10],[11]}

Our study aims to bring out the full potential of DYNA CT with regard to its use in TACE. This includes not only assessing the iodized oil deposition but also to help guide selective catheter placement and identify additional lesions and supplying arteries not diagnosed on pre-TACE imaging.

Methods

We conducted a prospective observational study over a period of 3 years (2017 to 2020) including 24 patients of HCC diagnosed on the basis of imaging, biopsy, and/or biochemical (AFP >400 IU) [presence of any two of three modalities] and were candidates for TACE based on Barcelona Clinic Liver Cancer staging. We excluded patients with severe renal failure, coagulopathy, portal vein thrombosis, and untreated esophageal varices. After assessing the demographic profile and biochemical values (AFP), the patients were admitted to our institute.

Study design

Patients to be taken for TACE underwent preprocedure contrast CT and magnetic resonance imaging (MRI) to assess the lesion and the arterial supply. TACE was done using chemotherapeutic drug emulsion, and intraprocedural DYNA CT was done in all patients to assess drug deposition, additional lesions, and any additional supplying artery, especially in those with inhomogeneous deposition of the drug. The drug deposition was correlated to therapeutic response based on postprocedural MRI. The identification and change in management of patients in whom DYNA CT showed additional lesions or arteries was also noted.

Imaging techniques

After initial clinical and biochemical workup, patients were subjected to preprocedural triphasic CT and MRI.

Computed tomography

Triphasic MDCT of the liver was performed on a 64-MDCT scanner (Somatom Sensation 64, Siemens Medical Solutions) using 100 mL of IV contrast agent (Contrapaque), 300 mg I/mL; flow rate, 3.5 mL/s with following parameters: 120 kVp; 160 mAs; collimation, 16 mm × 1.5 mm; and slice thickness, 2 and 5 mm. Images were obtained in arterial (25–35 s), venous (45–60 s), and delayed phase (3–5 min) using the bolus tracking method with the trigger on abdominal aorta. MDCT images of each patient were interpreted and the number and location of the detected hepatic lesions were documented.

Magnetic resonance imaging

Pre-and post- (4–6 weeks) TACE evaluation was done using 1.5-T MRI scanner (Magnetom Avanto, Siemens Medical Systems, Germany) equipped with phased array torso surface coil to cover the whole liver using the following sequences:

T1 weighted (T1W) (FLASH 2d) (FS axial): TR - 7.15 ms, TE - 2.3 ms, flip angle - 70°, and band width - 230 Hz
T2W images (single shot fast spin echo sequence) (HASTE): TR - 900 ms, TE - 92 ms, flip angle - 15°, and band width - 411 Hz.
Diffusion-weighted imaging: Respiratory-triggered fat-suppressed single-shot echo planar DW imaging with b values 0, 500, and 800 s/mm². TR = 1852 ms, TE = 70 ms, number of excitations = 3, matrix 150 × 236 with a field of view as small as possible, slice thickness = 4 mm, slice gap = 0.5 mm, and a scan time of approximately 5 min
Dynamic contrast-enhanced MRI (CEMRI): Dynamic imaging using VIBE technique was performed using TR = 4.3 ms, TE = 1.97, flip angle = 10°, and bandwidth = 400 Hz after injection of gadolinium-based contrast agent (Gadodiamide, OMNISCAN) 0.05–0.1 mmol/Kg at a rate of 2 mL/s. Following a noncontrast image, scans were obtained in early arterial phase, late arterial phase, portal phase, and delayed phase (3–5 min).

Transarterial chemoembolization

TACE was performed in a DSA suite (SEIMENS ARTIS ZEE DSA) by an interventional radiologist with more than 5 years of experience. An initial DSA aortography was done to identify the feeding vessels and the supplied lesions. After selective cannulation of the feeding arteries [Figure 5], embolization was done using chemotherapeutic emulsion in the following ratio: 20 mL of iodized oil (Lipiodol Ultrafluid) and 7 mL (60 mg) of epirubicin hydrochloride (Farmarubicin, Pfizer) and 7 mL of contrast (iohexol). The total volume administered was based on the size and number of lesions with endpoint being appearance of winter tree appearance, which was followed by gelatin particle infusion. 60 mg of epirubicin was the maximum drug that was administered in a single session.

Figure 1: A 56-year-old male with hepatocellular carcinoma in the right lobe of the liver. Conventional digital subtraction angiography (a) showed right hepatic artery branches with overlap and poor separation. It was difficult to identify the feeding vessel of the tumor due to vascular overlapping. Volume-rendering image of the DYNA computed tomography in frontal (b) and right oblique view (c and d) provided the three-dimensional information in the right hepatic artery and the branches could be separated for selective cannulation

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Figure 2: A 65-year-old male with hepatocellular carcinoma lesion in the right lobe of the liver (segment 8) (not shown) planned for TACE with Pre-TACE contrast-enhanced computed tomography (a) not showing any additional lesion in segment 6 of the liver and no lesion was found on digital subtraction angiography images; (b) however, on rotational angiography with C-arm computed tomography, additional lesion in segment 6 of liver (c) (blue arrow) was identified which was less than 10 mm in size and was subsequently embolized

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Figure 3: Type of lipiodol deposition in various patients. Type 1 deposition (a and b) of lipiodol in two patients indicating successful chemoembolization. Type C deposition (c) in one lesion (blue arrow) indicating incomplete chemoembolization, repeat angiography in this case showed that the lesion had an extrahepatic arterial supply from right inferior phrenic artery. Type 2 deposition (d) of lipiodol in the right lobe lesion (blue arrow), this lesion was in watershed region supplied by additional intrahepatic artery

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Figure 4: A 57-year-old male with hepatocellular carcinoma in the right lobe of the liver. Preprocedural CECT (a) showing arterial phase enhancing hepatocellular carcinoma lesion in segment 6 (blue arrow). MIP imaging (b) of rotational DYNA computed tomography showing segmental arterial branches supplying the lesion. VRT images (c) showing the vascular anatomy of the lesion. Lipiodol deposition (d) in the lesion on DSA. Post TACE completion DYNA computed tomography (e) showing homogenous type 1 deposition of contrast in the lesion

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Figure 5: Some of the commonly used equipment in TACE: A- Microcatheter with guidewire; B-Guidewire of microcatheter; C -RC catheter; D-SIM -1 catheter; E-Vascular puncture needle; F-Dilator; G-Vascular sheath

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DYNA computed tomography

An intraprocedure DYNA CT was done in all patients to assess the drug deposition and technical success of chemoembolization. DYNA CT sequences were acquired using a standardized protocol in a DYNA CT–capable uniplanar interventional suite (Siemens AXIOM Artis Zee floor mounted system; Siemens AG, Healthcare Sector, Forchheim, Germany) with a 30–40 cm flat-panel detector. Contrast DYN CT was obtained after injecting the contrast in the aorta to identify any additional lesions or feeding arteries. Selective contrast injection DYNA CT was done only when there was a difficulty in gaining selective access due to tortuous course or acute angulations. Images were acquired by injection of a 40-mL bolus of contrapaque diluted with saline (8 ml) solution using a power injector with a flow rate of 6 ml/s. Data were acquired starting 4 s after the patient received an intra-arterial injection of contrast material for arterial phase. Image processing and 3D rendering was performed at the time of the procedure on a Synge-X Workstation using Syngo InSpace 3D and Syngo DYNA CT algorithms (Siemens AG, Healthcare Sector).

The number and origin of the tumor-feeding arteries and catheter position for TACE was correlated after reviewing the images from the two techniques. The type of deposition in the lesion was divided into four categories: Type I - homogeneous accumulation, Type II - partial defect in the tumor deposition, Type III - faint accumulation, and Type IV - no or slight accumulation. TACE therapy was considered complete if the DYNA CT images showed Type I iodized oil retention patterns within the tumor, but further slow iodized oil embolization (1 ml/min) was undertaken in case of incomplete deposition. The incomplete deposition due to a missed arterial or extrahepatic supply was usually indicated by a well-demarcated area of nondeposition while that due to inadequate volume was more distributed all over the lesion.

Statistical analysis

The data were analyzed by the principle investigator with advice from a statistician. IBM SPSS Statistics for Windows, Version 22.0. (IBM Corp., Armonk, NY) was used for the statistical analysis. Categorical variables were analyzed using Pearson's Chi-square test. P < 0.05 was considered statistically significant.

Results

Patient profile

We included 24 patients in our study with a male-to-female ratio of 21 (87.5%): 3 (12.5%) having a mean age of 59.4 ± 9.4 years (range 42–73 years).

Clinical profile

We had 13 (54%) patients who were known cirrhotics, while 11 (46%) others were subsequently detected to have cirrhotic livers. The cause of cirrhosis among our patients included chronic viral hepatitis (hepatitis B and C) (n = 10), nonalcoholic steatohepatitis (n = 4), chronic alcohol abuse (n = 4), and cryptogenic (n = 6). The overall clinical assessment of the patients was done based on Child–Pugh scoring. 13 (54%) patients were in class A, whereas 11 (46%) patients were classified into class B of Child–Pugh score. Class C patients were excluded from the study in view of deranged coagulogram/liver function test and poor functional reserve.

Diagnosis

The diagnosis of HCC was based on the presence of any two of the three criteria: characteristic imaging findings, raised AFP levels (>400 IU), and histopathological findings. 18 (75%) patients were diagnosed by imaging and raised AFP levels, whereas 6 (25%) patients had to undergo biopsy for the diagnosis of HCC in view of the atypical imaging appearance or low AFP levels.

Imaging

Size of the lesion

The mean size of the lesions in our study was 4.25 ± 1.34 cm (0.6–7.3 cm). The largest dimension of the lesion was taken into account when measuring the size. Most of the lesions were seen in the right lobe of the liver.

Lesion detection

CECT detected a total of 36 lesions in 24 patients with a mean of 1.5 lesions per patient (3 lesions <10 mm, 4 lesions 10–20 mm, and 29 lesions >20 mm). DSA method detected 33 lesions in 24 patients with a mean of 1.37 lesions per patient (4 lesions 10–20 mm size and 29 lesions >20 mm). DSA was not able to detect lesions <10 mm. DYNA CT detected 39 lesions in 24 patients with a mean of 1.63 lesions per patient (5 lesions <10 mm and 5 lesions 10–20 mm and 29 lesions >20 mm size). The additional lesions detected by DYNA CT were seen mostly in the right lobe segments [Table 1].

Table 1: The sensitivity of various imaging modalities for lesion detection based on the size of the lesion

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Vascular supply of the lesion

42 tumor-feeding arteries were identified using DSA. Most of the vessels were identified in the right lobe (segment 8 and segment 5) owing to the increased number of lesions detected in these segments. DYNA CT identified 46 tumor-feeding arteries in 39 lesions in 24 patients, with a mean of 1.1 arteries per lesion. The additional four tumor-feeding arteries on DYNA CT included 2 branches of the hepatic artery supplying segment 8 lesion of the liver (watershed region). Two additional extrahepatic arteries included right inferior phrenic artery supplying right lobe tumor and a branch of left gastric artery supplying a left lobe tumor.

We had 3 (12%) patients in whom selective identification and cannulation of the feeding artery was difficult on DSA owing to vascular overlapping or vascular tortuosity. DYNA CT in these patients was helpful in identifying and guiding cannulation using three-dimensional images as a reference [Figure 1]. In 6 (25%) patients, DYNA CT helped in improvement in catheter position in the form of more selective catheterization and avoidance of nonselective arteries, while in 18 patients (75%), DYNA CT was of no additional help.

Lipoidal deposition

Chemoembolization of total 39 lesions was done, out of which 35 (90%) lesions showed homogenous Type 1 deposition. Two lesions (5%) showed Type 2 deposition of lipiodol; these two lesions were in watershed regions with additional hepatic arterial supply detected on rotational angiography. The other two lesions (5%) showed type 3 deposition of lipiodol and DYNA CT showed an extrahepatic parasitic supply to these lesions. Additional drug and selective embolization was done in all four patients and type 1 deposition achieved.

Clinical and technical success

Technical success in the form of selective cannulation, drug delivery, and type 1 homogenous drug deposition was achieved in all 24 patients, 39 lesions and 46 arteries making our technical success 100%.

Clinical success in the form of complete response according to m-RECIST on 5-week post-TACE CEMRI was seen in 19 (79%) of our patients, while 5 (21%) patients showed incomplete response. None of our patients had stable disease or progression over a 6-month follow-up period.

Discussion

The need to transfer a patient to the CT room during an interventional procedure to gain three-dimensional information has long been a limitation in the armamentarium of the interventional radiologist. However, with the advent of DYNA CT within the interventional suite itself, major improvements in the interventional field are expected. Our study was aimed to assess the role of DYNA CT in chemoembolization of HCC and justify its use in all cases. We evaluated 24 patients with HCC who underwent segmental or subsegmental TACE at our institute. Every study patient underwent contrast-enhanced CT within 30 days before TACE. Our patients belonged to Child–Pugh class A (n = 13) and Child–Pugh class B (n = 11). This study proceeded in accordance with the guidelines of our institutional review board, and written informed consent for additional DYNA CT was obtained from each participating patient before entry into the study.

The identification of the lesion and its location are the initial steps in TACE and can sometimes be difficult owing to the vascular redistribution especially in cirrhotics. We compared the ability of various modalities to detect HCC lesions in our study. We found that DYNA CT depicted additional lesions in 6 patients (25%). Among these 6 patients 3 patients (12.5%) had a negative intraprocedural DSA and preprocedural MDCT, while in other 3 patients (12.5%), the lesions were visible at preprocedural cross sectional imaging but not on DSA. The ability of DYNA CT in detecting occult lesions has been previously documented by Togolini et al.,^[12] Ushijima et al.,^[13] and Lucatelli et al.^[14]

Thus, DYNA CT can help identify additional occult lesions, which can be a source of recurrence. We, therefore, believe that lesion count should be done on contrast DYNA CT so that no lesion goes undetected and untreated. With regard to lesion detection, we observed that lesions less than 10 mm were most notorious and occult on DSA as well as preprocedure contrast-enhanced CT and becoming apparent only on intraprocedural DYNA CT [Table 1]. We had six lesions that were localized only on intraprocedural DYNA CT and would have been left untreated without the use of DYNA CT [Figure 2]. Most of these small occult lesions were seen in the right lobe and in cirrhotics. This is probably due to difference in hepatic vascularity in cirrhotics, difference in the contrast delivery when given in the peripheral veins or inability of DSA to localize lesions in deep segments of liver. For lesions >10 mm in size, we found no significant difference in localization among various modalities (CECT, DSA, and DYNA CT). Our results are in concordance with observations of Meyer et al.^[15] and Iwazawa et al.^[16] We, therefore, believe that contrast DYNA CT during TACE should be a routine to improve lesion detection, especially smaller lesions <10 mm. This is especially important as smaller lesions show better response to local chemoembolization than larger lesions as indicated by Miraglia et al.^[17] in their study.

The success of chemoembolization mainly rests on the ability of the interventionist to selectively cannulate the vessel supplying the tumor and proper placement of the catheter beyond any branch vessels before drug administration. This can, in turn, reduce local recurrences and nontarget embolization-associated complications. We, in our study, evaluated any additional benefit of DYNA CT over DSA vis-à-vis identification of tumor-supplying arteries as well as their selective cannulation. We observed no change in the course of the procedure in 18 (75%) of our patients. In these patients, DSA and DYNA CT were in concordance with each other regarding the number of supplying vessels (proximal position in the right hepatic artery = 9, peripheral position in the RHA = 4, proximal position in the LHA = 3, peripheral position in the LHA = 2) as well as catheter position before drug administration. In the remaining 6 patients, different catheter positions were chosen based on information from DSA and additional DYNA CT [Figure 1]. DYNA CT helped in catheter positioning in these patients in different ways such as more selective cannulation (n = 2), sparing of gastric artery (n = 1), inclusion of vessels originating from the other hepatic artery (n = 1), inclusion of Right inferior phrenic artery (n = 1), and inclusion of left gastric artery (n = 1). The number of tumor-feeding arteries identified on combined DSA and DYNA CT (46) was higher than the number identified on DSA alone (42). Two additional segmental arteries were identified in two patients supplying tumors in the right lobe of the liver. In one patient after completion of TACE, an inhomogeneous (Type 3) deposition of lipiodol was seen in a segment VIII lesion and a repeat angiography showed an additional branch from the right inferior phrenic artery supplying the tumor which was subsequently embolized. In another patient, DYNA CT depicted an additional branch supplying a left lobe tumor, which was found to be a branch of the left gastric artery, which was selectively embolized. This ability of DYNA CT to localize additional tumor-feeding vessels was also documented by previous researchers including Ushijima et al.,^[13] Lucatelli et al.,^[14] Meyer et al.,^[15] Iwazawa et al.,^[16] Virmani et al.,^[18] and Chan et al.^[19] The additional information provided by DYNA CT helped change the procedure in 6 (25%) of our patients, thereby improving the technical success. DYNA CT not only helps the interventional radiologist in identifying additional lesions and arteries supplying them but can also make him wiser regarding the catheter position and avoidance of side branches, especially in cases with tortuous and overlapping branches, thereby improving the overall efficacy of the procedure. This can also help reduce fluoroscopic time in these procedures; however, a separate study may be required to assess the radiation dose reduction to the operator and the patient.

The drug deposition within the lesion, which is an indicator of the technical success of the procedure, was previously assessed by NCCT after the procedure, and a poor deposition would mean a repeat procedure in the next setting. This is technically as well as economically difficult, especially in a resource-constrained environment like ours. DYNA CT provides an intraprocedural assessment of drug deposition and technical success [Figure 3]. Using intraprocedural DYNA CT, we identified type 1 deposition [Figure 4] in most of our patients (n = 35 90%), suggesting technical success. Type 2 deposition was seen in 2 lesions (5%) and Type 3 in two others (5%). The lesions with type 3 deposition were seen in segment 8 and segment 2 and on enhanced DYNA CT were supplied by extrahepatic inferior phrenic and left gastric arteries, respectively. Type 2 deposition was seen in lesions in watershed regions having additional hepatic arterial branches supplying them. In all these 4 patients, additional drug was given in the same setting, achieving type 1 deposition. The overall technical success in our study was therefore 100%. Our results are concordant with those of Togolini et al.,^[12] Iwazawa et al.,^[18] and Sun et al.^[19] who in their studies found additional advantages of C-arm CT in the management of HCC by TACE improving its technical and clinical success. We, therefore, suggest a completion DYNA CT to confirm diffuse homogenous drug deposition within the lesion and the need of any additional embolization. It should however be remembered that a type 1 deposition on completion DYNA CT may not necessarily mean a clinical success. We observed a complete response in 19 (79%) of our patients on post TACE CEMRI despite the fact that all patients had type 1 deposition on completion DYNA CT. Thus, although DYNA CT is a good indicator of technical success of TACE, it may not necessarily indicate a complete clinical response. However, lesions with good drug deposition are more likely to show good clinical response than those with heterogenous deposition.

The limitations of our study included the small study population which is probably because the procedure is in its inception in our part of the world. However, the results with DYNA CT are promising like many previous studies. Second, we were not able to compare the radiation dose to the patient and interventionist with and without the use of DYNA CT. Furthermore, the time benefit of DYNA CT with regard to feeding artery identification and a better overall three-dimensional picture of the anatomy was not assessed.

Conclusion

DYNA CT has the potential to markedly improve technical and clinical success of TACE. DYNA CT is the most sensitive modality in lesion detection, localization, and feeding artery (including extrahepatic) identification, especially lesions <10 mm. DYNA CT helps guide selective catheterization and selective chemoembolization. Completion DYNA CT can assess drug deposition and thereby the need of additional drug delivery, if needed. DYNA CT should therefore be commonly used in all TACE procedures.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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