Multiphasic Multidetector Computed Tomography Research Articles

Multiphasic MDCT of Living Renal Donors, Prior to Surgery

Background: Live kidney donor evaluation mandates anatomical and functional assessment of the donor kidney. Multiphasic Multidetector computed tomography (MDCT) with advanced 3‐D techniques provides a detailed description of the vascular, parenchymal, and collecting system. Objectives: To evaluate the clinical application of Multiphasic MDCT in the pre-operative anatomic assessment of prospective donor kidneys. Methods: Multiphasic MDCT was performed in thirty-eight patients as part of a pre-operative assessment. Each study comprised three phases of imaging, including the arterial, venous, and excretory phases. Results: The predominant radiological finding amongst the cases studied was that of the presence of accessory renal arteries in 35% of the patients. Multiphasic MDT was also able to detect renal parenchymal disease in one case. Post-renal anatomical evaluation also identified renal calculi in 12.5% of the total cases. Conclusions: There is considerable scope for multiphasic MDCT in the pre-operative evaluation of donor kidneys, especially as modern-day renal transplant surgery sees a shift towards laparoscopic techniques where intraoperative anatomic evaluation can be restricted. The multiphasic MDCT is useful in pre-renal, renal, and post-renal anatomic evaluation. Advances in Knowledge: Multiphasic MDCT can provide noninvasive, detailed, and fast images to aid the preoperative evaluation of donor kidneys.

Typical and Atypical Imaging Findings of Hepatocellular Carcinoma on Multiphasic MDCT Scan in Histologically Proved Cases

Abstract Objective The purpose of this study was to find out the incidence of typical and atypical radiological imaging findings of hepatocellular carcinoma (HCC) on multiphase multidetector computed tomography (MDCT) scans in histologically proven cases. Materials and Methods A multiphase computed tomography study of 73 patients with histologically proven HCC was evaluated by a radiologist. Our multiphasic protocol was composed of precontrast, arterial, portal, and delayed venous phases. The reviewers analyzed the CT images for tumor size, enhancement patterns of HCC in different phases, relative timing of washout, internal cystic changes, and presence of dysmorphic intratumoral vessel aneurysms or arteriovenous shunt. Results Most of the cases (95.9%) showed typical enhancement patterns in MDCT, i.e., enhancements in the arterial phase with the portal or delayed venous phase contrast washout. Three cases (4.9%) out of 73 HCC showed enhancements in the portal phase and washout in the delayed venous phase. Seven cases out of total 73 HCC (9.5%) patients showed heterogeneous enhancements in both arterial and portal phases and contrast washout in the delayed venous phase. Venous thrombosis was noted in about 44 cases (60%) out of total 73 patients, in which portal vein thrombosis was more common than hepatic veins/inferior vena cava. Conclusion Most of the HCC show typical enhancement patterns, i.e., heterogeneous enhancements in the arterial phase and washout in the portal venous phase when we use MDCT. These findings are higher than those described previously. However, in our study, the main difference with MDCT was lower frequency of intratumoral pseudoaneurysm and bile duct invasion, and intratumoral fat and calcification (atypical character of HCC) were not found which were rare findings in previous study.

Preoperative Predicting the WHO/ISUP Nuclear Grade of Clear Cell Renal Cell Carcinoma by Computed Tomography-Based Radiomics Features.

Nuclear grade is important for treatment selection and prognosis in patients with clear cell renal cell carcinoma (ccRCC). This study aimed to determine the ability of preoperative four-phase multiphasic multidetector computed tomography (MDCT)-based radiomics features to predict the WHO/ISUP nuclear grade. In all 102 patients with histologically confirmed ccRCC, the training set (n = 62) and validation set (n = 40) were randomly assigned. In both datasets, patients were categorized according to the WHO/ISUP grading system into low-grade ccRCC (grades 1 and 2) and high-grade ccRCC (grades 3 and 4). The feature selection process consisted of three steps, including least absolute shrinkage and selection operator (LASSO) regression analysis, and the radiomics scores were developed using 48 radiomics features (10 in the unenhanced phase, 17 in the corticomedullary (CM) phase, 14 in the nephrographic (NP) phase, and 7 in the excretory phase). The radiomics score (Rad-Score) derived from the CM phase achieved the best predictive ability, with a sensitivity, specificity, and an area under the curve (AUC) of 90.91%, 95.00%, and 0.97 in the training set. In the validation set, the Rad-Score derived from the NP phase achieved the best predictive ability, with a sensitivity, specificity, and an AUC of 72.73%, 85.30%, and 0.84. We constructed a complex model, adding the radiomics score for each of the phases to the clinicoradiological characteristics, and found significantly better performance in the discrimination of the nuclear grades of ccRCCs in all MDCT phases. The highest AUC of 0.99 (95% CI, 0.92–1.00, p < 0.0001) was demonstrated for the CM phase. Our results showed that the MDCT radiomics features may play a role as potential imaging biomarkers to preoperatively predict the WHO/ISUP grade of ccRCCs.

Differentiation of Clear Cell Renal Cell Carcinoma from other Renal Cell Carcinoma Subtypes and Benign Oncocytoma Using Quantitative MDCT Enhancement Parameters.

Background and objectives: The use of non-invasive techniques to predict the histological type of renal masses can avoid a renal mass biopsy, thus being of great clinical interest. The aim of our study was to assess if quantitative multiphasic multidetector computed tomography (MDCT) enhancement patterns of renal masses (malignant and benign) may be useful to enable lesion differentiation by their enhancement characteristics. Materials and Methods: A total of 154 renal tumors were retrospectively analyzed with a four-phase MDCT protocol. We studied attenuation values using the values within the most avidly enhancing portion of the tumor (2D analysis) and within the whole tumor volume (3D analysis). A region of interest (ROI) was also placed in the adjacent uninvolved renal cortex to calculate the relative tumor enhancement ratio. Results: Significant differences were noted in enhancement and de-enhancement (diminution of attenuation measurements between the postcontrast phases) values by histology. The highest areas under the receiver operating characteristic curves (AUCs) of 0.976 (95% CI: 0.924–0.995) and 0.827 (95% CI: 0.752–0.887), respectively, were demonstrated between clear cell renal cell carcinoma (ccRCC) and papillary RCC (pRCC)/oncocytoma. The 3D analysis allowed the differentiation of ccRCC from chromophobe RCC (chrRCC) with a AUC of 0.643 (95% CI: 0.555–0.724). Wash-out values proved useful only for discrimination between ccRCC and oncocytoma (43.34 vs 64.10, p < 0.001). However, the relative tumor enhancement ratio (corticomedullary (CM) and nephrographic phases) proved useful for discrimination between ccRCC, pRCC, and chrRCC, with the values from the CM phase having higher AUCs of 0.973 (95% CI: 0.929–0.993) and 0.799 (95% CI: 0.721–0.864), respectively. Conclusions: Our observations point out that imaging features may contribute to providing prognostic information helpful in the management strategy of renal masses.

Triple-phase multidetector computed tomography:an evaluation of hepatic space occupying lesion in cirrhotic patients

Hepatocellular carcinoma (HCC) is a common tumor with an incidence of 1 - 6 % among cirrhotic patients. Dysplastic nodule often occurs within regenerative cirrhotic nodules. They can show low or high grade dysplasia. MRI best differentiates this iso-or hypo intense lesion from hyper intense HCC. The current study was designed to assess the usefulness of Triple-phase multiphasic multidetector computed tomography (MDCT) in evaluation of hepatic space occupying lesion in cirrhotic patients.This cross sectional study was carried out in Radiology and Imaging department in collaboration with Hepatology and Hepatobiliary surgery department, of Bangabandhu Sheikh Mujib Medical University, Dhaka during July 2014 to June 2016. A total of 62 cirrhotic patients with hepatic space occupying lesion were included in this study. MDCT was done in all these patients and they were followed-up from the admission up to post operative tissue diagnosis of hepatic space occupying lesion in respective pathology departments to assess the histopathological correlation. Patients with suspected hepatic space occupying lesion diagnosed by clinical andultrasonography and having high serum α-fetoprotein level were enrolled. The mean age was 50.0±13.6 years with ranged from 25 to 79 years. Male female ratio was 2.3:1.In MDCT, a total of 54 malignant cases were found, out of which 49(79.0%) patients had HCC, 4(6.5%) had metastases and 1(1.6%) had dysplastic nodule. In benign tumor group, 6(9.7%) patients had cirrrhotic nodule, 1(1.6%) had hepatic adenoma and 1(1.6%) had haemangioma. In histopahology, a total 53 malignant cases were found, out of them 48(77.5%) patients had HCC, 3(4.8%) had metastases and 2(3.2%) had dysplastic nodule. Triphasic MDCT in diagnosis of hepatic space occupying lesion in cirrhotic patients revealed a sensitivity of 98.1%, specificity of 77.8%, accuracy 95.2%, positive predictive values 96.3% and negative predictive values 87.5%. While the same diagnostic tool showed a sensitivity95.8%, specificity 78.6%, accuracy 91.9%, positive predictive values 93.9% and negative predictive values 84.6% in identification of HCC. In evaluation of metastasis MDCT had a sensitivity of 100.0%, specificity 98.3%, accuracy 98.4%, positive predictive values 75.0% and negative predictive values 100.0%. In evaluation of dysplastic nodule MDCT had sensitivity 50.0%, specificity 100.0%, accuracy 98.4%, positive predictive values 100.0% and negative predictive values 98.4%.So, MDCT can be an ideal diagnostic tool for detecting as well as characterizing the hepaticspace occupying lesion (SOLs) in cirrhotic patients.Bangladesh Med Res Counc Bull 2018; 44(1):23-29

Emergency CT for assessment and management of blunt traumatic splenic injuries at a Level 1 Trauma Center: 13-year study.

To determine the relationship between multidetector computed tomography (MDCT) findings, management strategies, and ultimate clinical outcomes in patients with splenic injuries secondary to blunt trauma. This Institutional Review Board-approved study collected 351 consecutive patients admitted at the Emergency Department (ED) of a Level I Trauma Center with blunt splenic trauma between October 2002 and November 2015. Their MDCT studies were retrospectively and independently reviewed by two radiologists to grade splenic injuries according to the American Association for the Surgery of Trauma (AAST) organ injury scale (OIS) and to detect intraparenchymal (type A) or extraparenchymal (type B) active bleeding and/or contained vascular injuries (CVI). Clinical data, information on management, and outcome were retrieved from the hospital database. Statistical analysis relied on Student's t, chi-squared, and Cohen's kappa tests. Emergency multiphase MDCT was obtained in 263 hemodynamically stable patients. Interobserver agreement for both AAST grading of injuries and vascular lesions was excellent (k= 0.77). Operative management (OM) was performed in 160 patients (45.58% of the whole cohort), and high-grade (IV and V) OIS injuries and type B bleeding were statistically significant (p< 0.05) predictors of OM. Nonoperative management (NOM) failed in 23 patients out of 191 (12.04%). In 75% of them, NOM failure occurred within 30h from the trauma event, without significant increase of mortality. Both intraparenchymal and extraparenchymal active bleeding were predictive of NOM failure (p< 0.05). Providing detection and characterization of parenchymal and vascular traumatic lesions, MDCT plays a crucial role for safe and appropriate guidance of ED management of splenic traumas and contributes to the shift toward NOM in hemodynamically stable patients.

Utility of multiphasic multidetector computed tomography in discriminating between clear cell renal cell carcinomas with high and low carbonic anhydrase-IX expression.

To investigate if multiphasic multidetector computed tomography (MDCT) enhancement profiles can distinguish clear cell renal cell carcinomas (ccRCCs) with high carbonic anhydrase-IX (CA-IX) expression from ccRCCs with low CA-IX expression. With IRB approval for this retrospective study, we derived a cohort of 105 histologically proven ccRCCs with preoperative 4-phase renal mass MDCT from 2001 to 2013. Following manual segmentation, the computer-assisted detection algorithm selected a 0.5-cm-diameter region of maximal attenuation within each lesion in each phase. CA-IX expression level was determined by immunohistochemical staining of tumor specimens. In the high and low CA-IX expression subgroups, the magnitude of enhancement and washout were compared using t tests; the performance of contrast washout in differentiating between subgroups was assessed with logistic regression analysis. ccRCCs with high and low CA-IX expression both exhibited peak enhancement in the corticomedullary phase. ccRCCs with high CA-IX expression demonstrated significantly greater relative nephrographic washout than those with low CA-IX expression (18.4% vs. 7.8%, p=0.03). ccRCCs with high CA-IX expression had greater relative excretory washout than ccRCCs with low CA-IX expression with a trend toward significance (33.4% vs. 25.2%, p=0.05). After controlling for tumor size and stage, for distinguishing ccRCCs with high and low CA-IX expression, relative excretory washout had a sensitivity, negative predictive value, accuracy, and positive predictive value of 99% (65/66), 88% (7/8), 69% (72/105), and 67% (65/97), respectively. Relative nephrographic and excretory washout may have the potential to help distinguish ccRCCs with high and low CA-IX expression, but this requires further validation.

Sarcomatoid Renal Cell Carcinoma and Collecting Duct Carcinoma: Discrimination From Common Renal Cell Carcinoma Subtypes and Benign RCC Mimics on Multiphasic MDCT

To investigate whether imaging features on multiphasic multidetector computed tomography (MDCT) can help discriminate sarcomatoid renal cell carcinoma (RCC) and collecting duct carcinoma (CDC) from other solid renal masses. With institutional review board approval for this HIPAA-compliant study, we derived a cohort of 7 sarcomatoid RCCs, 4 CDCs, 165 clear cell RCCs, 56 papillary RCCs, 22 chromophobe RCCs, 49 oncocytomas, and 16 lipid-poor angiomyolipomas with preoperative multiphasic MDCT with up to four phases (unenhanced, corticomedullary, nephrographic, and excretory). Each lesion was reviewed for contour, spread pattern, pattern of enhancement, neovascularity, and calcification. Sarcomatoid RCCs and CDCs were more likely than other solid renal masses to have an irregular contour (64% vs 2%, P < 0.001) and an infiltrative spread pattern, defined as infiltration into adjacent renal parenchyma, collecting system, or neighboring structures (82% vs 7%, P < 0.001). When used to discriminate sarcomatoid RCC and CDC from other solid renal masses, an infiltrative spread pattern had a specificity of 93% (287/308) and sensitivity of 82% (9/11), and an irregular contour had a specificity of 98% (303/308) and sensitivity of 64% (7/11). Solid renal lesions with an irregular contour or an infiltrative spread pattern are suspicious for sarcomatoid RCC or CDC.

Clear cell renal cell carcinoma: identifying the gain of chromosome 20 on multiphasic MDCT.

To investigate whether multiphasic multidetector computed tomography (MDCT) enhancement can help identify the gain of chromosome 20 in clear cell renal cell carcinomas (RCCs), a rare prognostically significant cytogenetic abnormality. With the Institutional Review Board approval, we queried our institution's pathology database to derive a cohort of 52 cases of clear cell RCC with preoperative four-phase renal mass protocol MDCT and karyotypes of the resected specimens during a 10-year period. Each lesion was evaluated for absolute and relative (compared to contralateral normal renal cortex) attenuations in each phase. Relative attenuation was calculated as [(lesion attenuation-cortex attenuation)/cortex attenuation]×100. The absolute and relative attenuations were compared using t-tests. Clear cell RCCs with the gain of 20 had significantly less nephrographic and excretory phase enhancement than clear cell RCCs without the gain of 20 (86.4 HU vs. 111.4 HU, p=0.007; 70.0 HU vs. 89.4 HU, p=0.003; respectively). Additionally, the relative nephrographic and excretory phase attenuations of clear cell RCCs with the gain of 20 were significantly less than that of clear cell RCCs without the gain of 20 (-52.7 vs. -34.7, p=0.002; -44.9 vs. -31.1, p=0.005; respectively). Multiphasic MDCT enhancement may assist in identifying the gain of chromosome 20 in clear cell RCCs, if validated in a large prospective trial.

Sectional Localization of a Small Hepatocellular Carcinoma in the Right Hepatic Lobe by Computed Tomography: Comparison between the Conventional and Portal Vein Tracing Methods.

To compare the accuracy of the conventional and portal vein tracing methods in the right hepatic lobe in multidetector computed tomography (MDCT). This retrospective study included patients with hepatocellular carcinoma (HCC) lesions in the right hepatic lobe who underwent multiphasic MDCT and C-arm CT hepatic arteriography (C-arm CTHA) for chemoembolization. The accuracies of the conventional and portal vein tracing methods were evaluated using C-arm CTHA as the gold standard. A total of 147 patients with 205 HCC nodules were included. The C-arm CTHA could identify all the tumour-feeding arteries and consequently demonstrated that 120 lesions were located in the anterior section, 78 in the posterior section, and 7 in the border zone. The accuracy rates of conventional vs. portal vein tracing methods were 71.7 % vs. 98.3 % for the anterior section lesions, 67.9 % vs. 96.2 % for the posterior section, and 28.6 % vs. 57.1 % for the border zone. The portal vein tracing method was more accurate than the conventional method (P<0.001). The portal vein tracing method should be used for sectional localization of HCCs in the right lobe, because it predicts the location more accurately than the conventional method. • Portal tracing method is more accurate than conventional method for tumour localization. • The conventional method is especially inaccurate in right anteroinferior or posterosuperior quadrants. • Scissurae between right anterior and posterior section may not be vertical but tilted.

Comparison of Multidetector CT and Gadobutrol-Enhanced MR Imaging for Evaluation of Small, Solid Pancreatic Lesions.

ObjectiveTo compare multidetector computed tomography (MDCT) and MRI for lesion conspicuity, as well as the detection and characterization of small solid pancreatic lesions (SPLs).Materials and Methods193 patients with small SPLs (< 3 cm) and 52 patients with normal pancreas who underwent both multiphasic MDCT and gadobutrol-enhanced MRI were included in our study. Two radiologists blinded to the pathologic diagnoses independently reviewed those images, and determined the detection of "SPL per se" and "SPL in consideration of secondary features", the lesion conspicuity, the probability of pancreatic ductal adenocarcinoma (PDAC), and the most likely specific diagnosis.ResultsThe sensitivity of MRI for "detection of SPL per se" was significantly higher than that of CT in both reviewers: 92.7% (179/193) and 97.9% (189/193), respectively, for reviewer 1 (p = 0.031) and 90.7% (175/193) and 99.5% (192/193), respectively, for reviewer 2 (p < 0.001). In addition, MRI provided better lesion conspicuity than MDCT for both reviewers (p < 0.001). However, CT and MRI did not show significant difference in sensitivity for "detection of SPL in consideration of secondary features", specificity for SPL detection, and differentiation of PDAC vs. non-PDAC (p > 0.05). The accuracies of CT and MRI for making a specific diagnosis were as follows: 85.7% (210/245) vs. 86.9% (213/245), respectively, for reviewer 1 (p = 0.736), and 91.8% (225/245) vs. 93.5% (229/245), respectively, for reviewer 2 (p = 0.454).ConclusionMRI showed better lesion conspicuity than MDCT, but did not show significantly different diagnostic performance compared with MDCT for detecting and characterizing small SPLs.

Contrast enhancement pattern on multidetector CT predicts malignancy in pancreatic endocrine tumours.

Preoperative suspicion of malignancy in pancreatic neuroendocrine tumours (pNETs) is mostly based on tumour size. We retrospectively reviewed the contrast enhancement pattern (CEP) of a series of pNETs on multiphasic multidetector computed tomography (MDCT), to identify further imaging features predictive of lesion aggressiveness. Sixty pNETs, diagnosed in 52 patients, were classified based on CEP as: type A showing early contrast enhancement and rapid wash-out; type B presenting even (B1) or only (B2) late enhancement. All tumours were resected allowing pathologic correlations. Nineteen pNETs showed type A CEP (5-20 mm), 29 type B1 CEP (5-80 mm) and 12 type B2 (15-100 mm). All tumours were classified as well differentiated tumours, 19 were benign (WDt-b), 15 with uncertain behaviour (WDt-u) and 26 carcinomas (WDC). None of A lesions were malignant (12 WDt-b; 7 WDt-u), all B2 lesions were WDC, 7 B1 lesions were WDt-b, 8 WDt-u and 14 WDC; 4/34 (12 %) lesions ≤2cm were WDC. CEP showed correlation with all histological prognostic indicators. Correlating with the lesion grading and other histological prognostic predictors, CEP may preoperatively suggest the behaviour of pNETs, assisting decisions about treatment. Moreover CEP allows recognition of malignant small tumours, incorrectly classified on the basis of their dimension.

Role of multiphasic multi-detector computed tomography (MDCT) in the diagnosis and staging of solid neoplastic renal masses

ObjectivesThe aim of this study was to assess the role of multi-detector computed tomography (MDCT) in diagnosis and preoperative staging of solid renal masses. Patients and methodsDuring two years duration we prospectively evaluated 56 patients with solid renal lesions previously detected by US. All patients underwent multiphasic CT scanning for the kidneys and urinary tract following a preset scanning protocol that included unenhanced, corticomedullary phase (CMP), nephrograhic phase (NP) and excretory phase (EP) scanning. The images obtained in the excretory delayed phase were reconstructed in different planes to obtain 2D and 3D reformatted images providing volume rendering VR and maximum intensity projection (MIP) CTU images. Curved reformatting was sometimes used for the ureter. The numbers of lesions detected in all three phases were determined. Results of CT scan were compared with histopathology or constellation of clinical and imaging patient data. ResultsA total of 61 masses were detected in 56 cases, 51 cases had unilateral masses (91%), 5 cases had bilateral masses (9%). The different pathologies encountered in the study were RCC 39 masses (64%), Wilm’s tumor 3 masses (4.9%), transitional cell carcinoma 3 masses (4.9%), angiomyolipoma 7 masses (11.5%), lymphoma 6 masses (9.8%), metastasis one mass (1.6%), angiomyolipoma associated with RCC two masses (3.3%). Lymph nodal metastasis, renal vein, IVC thrombosis and distant metastatic spread in different pathologies were assessed.The attenuation HU values calculated in the early CMP for all cases of RCC had a mean value of 80.5HU (STD 45.7) while the mean values in NP and EP were 70.6HU (STD 25.4) and 51.3HU (STD 19.2) respectively.A pattern of enhancement was detected in all cases of RCC in the form of rapid wash out of contrast and decrease of attenuation (HU) by time throughout different phases.Significant difference between HU in CMP and EP in cases of RCC (P value=0.0002) and difference between HU in NP and EP in cases of RCC (P value<0.00001) were found. ConclusionMultiphase multislice computed tomography combined with CT angiography and CT urography have a major role in solid renal neoplastic masses’ diagnosis, characterization and differentiating benign and malignant tumors.

Dynamic enhancement pattern of HCC smaller than 3 cm in diameter on gadoxetic acid‐enhanced MRI: comparison with multiphasic MDCT

The dynamic enhancement pattern of HCCs smaller than 3 cm in diameter on gadoxetic acid-enhanced magnetic resonance imaging (MRI) have not been extensively investigated. We aimed to evaluate the dynamic enhancement patterns of small HCCs (≤3 cm) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) and compare enhancement patterns with multiphasic multidetector computed tomography (MDCT) based on tumour cellular differentiation and size. We retrospectively included 55 patients with 67 surgically confirmed small HCCs (≤3 cm) who underwent multiphasic MDCT and gadoxetic acid-enhanced MRI. Dynamic enhancement patterns were analysed according to tumour cellular differentiation and size. Hepatobiliary phase images were also analysed to assess their additional value. The proportion of small HCCs demonstrating the typical enhancement pattern differed depending on tumour cellular differentiation on both MRI (P = 0.001) and MDCT (P = 0.001), but differed depending on tumour size only on CT (P = 0.008). Gadoxetic acid-enhanced MRI more sensitively depicted the typical enhancement pattern than CT for all tumours (P = 0.001), for moderately or poorly differentiated HCCs (P = 0.021) and for HCCs ≤2 cm (P = 0.001). 80% of tumours with atypical enhancement could be diagnosed as HCC based on tumour size and hepatobiliary phase images. On both gadoxetic acid-enhanced MRI and multiphasic CT, the dynamic enhancement patterns of small HCCs (≤3 cm) differed according to tumour cellular differentiation. Gadoxetic acid-enhanced MRI more frequently demonstrated the typical HCC enhancement pattern than CT in small HCCs.

Three-phase, contrast-enhanced, multidetector CT in the evaluation of complicated renal cysts: comparison of the postcontrast phase combination

Multiphasic multidetector computed tomography (MDCT) is widely used for the assessment and diagnosis of complicated renal cysts. To determine the optimal combination of postcontrast phases of MDCT for the evaluation of complicated renal cysts. In 164 renal cysts with pathology confirmation or follow-up >2 years, the Bosniak category was recorded by two radiologists in consensus. They reviewed the MDCT images during three interpretation sessions. In the first session, the radiologists evaluated two phases of images (unenhanced and corticomedullary phases), while during the second session, they evaluated two phases of images (unenhanced and parenchymal phases), and in the third session, they evaluated all three phases of images (unenhanced, corticomedullary, and parenchymal phases). The diagnostic accuracy for evaluating renal cysts was compared in each session using receiver-operating characteristics (ROC) analysis. There were 106 benign renal cysts and 58 malignant renal cysts. The areas under the ROC curves (AUCs) of the second and third sessions were greater than that of the first session (P < 0.05). The sensitivity, specificity, positive predictive value, and negative predictive value of the first session were 74%, 88%, 77%, and 86%, respectively, and those of the second session were 90%, 85%, 77%, and 94%, respectively. The values of the third session were identical to those of the second session. Unenhanced and parenchymal phase CT scans are sufficient for differentiating malignant from benign renal cysts and there was no additional value by adding the corticomedullary phase to the combination of unenhanced and parenchymal phase CT.

Clear cell renal cell carcinoma: multiphasic MDCT enhancement can predict the loss of chromosome 8p

To investigate whether imaging features on multiphasic multidetector computed tomography (MDCT) can predict the loss of chromosome 8p in clear cell renal cell carcinomas (RCCs), a cytogenetic abnormality associated with a higher tumor grade and greater risk of recurrence. With IRB approval for this HIPAA-compliant retrospective study, we queried our institution's pathology database to derive all histologically proven cases of clear cell RCC with preoperative multiphasic MDCT with as many as four phases (unenhanced, corticomedullary, nephrographic, and excretory) from January 2000 to July 2010. Of 170 clear cell RCCs with preoperative multiphasic MDCT, 105 clear cell RCCs, representing 98 unique patients, had karyotypes of the resected specimens. Lesions were evaluated for magnitude and pattern of enhancement, contour, neovascularity, calcifications, and size. The corticomedullary phase mean enhancement of clear cell RCCs with a loss of 8p was significantly greater than that of clear cell RCCs without a loss of 8p (169.5 vs. 127.2 HU, p = 0.004). A threshold of 165 HU predicted the loss of 8p in clear cell RCCs with an accuracy of 78% (69/88), a specificity of 81% (62/77), and a negative predictive value of 94% (62/66). There were no significant differences in the pattern of enhancement, contour, neovascularity, calcification, or size between clear cell RCCs with a loss of 8p and those without this abnormality. Enhancement on multiphasic MDCT can predict the loss of 8p in clear cell RCCs and can thus provide a non-invasive means of guiding further management, including surgery, ablation, watchful waiting, or medical management.

Dual-phase Cone-beam Computed Tomography to See, Reach, and Treat Hepatocellular Carcinoma during Drug-eluting Beads Transarterial Chemo-embolization

The advent of cone-beam computed tomography (CBCT) in the angiography suite has been revolutionary in interventional radiology. CBCT offers 3 dimensional (3D) diagnostic imaging in the interventional suite and can enhance minimally-invasive therapy beyond the limitations of 2D angiography alone. The role of CBCT has been recognized in transarterial chemo-embolization (TACE) treatment of hepatocellular carcinoma (HCC). The recent introduction of a CBCT technique: dual-phase CBCT (DP-CBCT) improves intra-arterial HCC treatment with drug-eluting beads (DEB-TACE). DP-CBCT can be used to localize liver tumors with the diagnostic accuracy of multi-phasic multidetector computed tomography (M-MDCT) and contrast enhanced magnetic resonance imaging (CE-MRI) (See the tumor), to guide intra-arterially guidewire and microcatheter to the desired location for selective therapy (Reach the tumor), and to evaluate treatment success during the procedure (Treat the tumor). The purpose of this manuscript is to illustrate how DP-CBCT is used in DEB-TACE to see, reach, and treat HCC.

Dual-phase Cone-beam Computed Tomography to See, Reach, and Treat Hepatocellular Carcinoma during Drug-eluting Beads Transarterial Chemo-embolization

The advent of cone-beam computed tomography (CBCT) in the angiography suite has been revolutionary in interventional radiology. CBCT offers 3 dimensional (3D) diagnostic imaging in the interventional suite and can enhance minimally-invasive therapy beyond the limitations of 2D angiography alone. The role of CBCT has been recognized in transarterial chemo-embolization (TACE) treatment of hepatocellular carcinoma (HCC). The recent introduction of a CBCT technique: dual-phase CBCT (DP-CBCT) improves intra-arterial HCC treatment with drug-eluting beads (DEB-TACE). DP-CBCT can be used to localize liver tumors with the diagnostic accuracy of multi-phasic multidetector computed tomography (M-MDCT) and contrast enhanced magnetic resonance imaging (CE-MRI) (See the tumor), to guide intra-arterially guidewire and microcatheter to the desired location for selective therapy (Reach the tumor), and to evaluate treatment success during the procedure (Treat the tumor). The purpose of this manuscript is to illustrate how DP-CBCT is used in DEB-TACE to see, reach, and treat HCC.

MDCT Imaging Findings of Liver Cirrhosis: Spectrum of Hepatic and Extrahepatic Abdominal Complications

Hepatic cirrhosis is the clinical and pathologic result of a multifactorial chronic liver injury. It is well known that cirrhosis is the origin of multiple extrahepatic abdominal complications and a markedly increased risk of hepatocellular carcinoma (HCC). This tumor is the sixth most common malignancy worldwide and the third most common cause of cancer related death. With the rising incidence of HCC worldwide, awareness of the evolution of cirrhotic nodules into malignancy is critical for an early detection and treatment. Adequate imaging protocol selection with dynamic multiphase Multidetector Computed Tomography (MDCT) and reformatted images is crucial to differentiate and categorize the hepatic nodular dysplasia. Knowledge of the typical and less common extrahepatic abdominal manifestations is essential for accurately assessing patients with known or suspected hepatic disease. The objective of this paper is to illustrate the imaging spectrum of intra- and extrahepatic abdominal manifestations of hepatic cirrhosis seen on MDCT.

Clear Cell Renal Cell Carcinoma: Discrimination from Other Renal Cell Carcinoma Subtypes and Oncocytoma at Multiphasic Multidetector CT

To determine whether enhancement at multiphasic multidetector computed tomography (CT) can help differentiate clear cell renal cell carcinoma (RCC) from oncocytoma, papillary RCC, and chromophobe RCC. With institutional review board approval for this HIPAA-compliant retrospective study, the pathology database was queried to derive a cohort of 298 cases of RCC and oncocytoma with preoperative multiphasic multidetector CT with as many as four phases (unenhanced, corticomedullary, nephrographic, and excretory). A total of 170 clear cell RCCs, 57 papillary RCCs, 49 oncocytomas, and 22 chromophobe RCCs were evaluated for multiphasic enhancement and compared by using t tests. Cutoff analysis was performed to determine optimal threshold levels to discriminate among the four groups. Mean enhancement of clear cell RCCs and oncocytomas peaked in the corticomedullary phase; mean enhancement of papillary and chromophobe RCCs peaked in the nephrographic phase. Enhancement of clear cell RCCs was greater than that of oncocytomas in the corticomedullary (125 HU vs 106 HU, P = .045) and excretory (80 HU vs 67 HU, P = .034) phases. Enhancement of clear cell RCCs was greater than that of papillary RCCs in the corticomedullary (125 HU vs 54 HU, P < .001), nephrographic (103 HU vs 64 HU, P < .001), and excretory (80 HU vs 54 HU, P < .001) phases. Enhancement of clear cell RCCs was greater than that of chromophobe RCCs in the corticomedullary (125 HU vs 74 HU, P < .001) and excretory (80 HU vs 60 HU, P = .008) phases. Thresholding of enhancement helped to discriminate clear cell RCC from oncocytoma, papillary RCC, and chromophobe RCC with accuracies of 77% (83 of 108 cases), 85% (101 of 119 cases), and 84% (81 of 97 cases). Enhancement at multiphasic multidetector CT, if prospectively validated, may assist in the discrimination of clear cell RCC from oncocytoma, papillary RCC, and chromophobe RCC.