Usefulness of the long-axis and short-axis reformatted images of multidetector-row CT in evaluating T-factor of the surgically resected pancreaticobiliary malignancies

Improved Diagnosis of Adjacent Organ Invasion of Extrahepatic Cholangiocarcinoma by Adding Arterial and Delayed Phases

PURPOSE

To clarify the role of dynamic computed tomography (CT) in diagnosing extrahepatic cholangiocarcinoma (eCCA) involving adjacent organs.

MATERIAL AND METHODS

We retrospectively analyzed patients diagnosed with eCCA in Iwate Medical University Hospital (Morioka, Japan) during January 2011-December 2021 who underwent dynamic contrast-enhanced CT before biliary intervention, surgery, or chemotherapy. For surgical cases, two radiologists independently reviewed CT images in the portal, dual (adding arterial phase), and triple (adding delayed phase) phases. The mean attenuations of the abdominal aorta, portal vein (PV), hepatic parenchyma, pancreatic parenchyma, and eCCA were measured. The biliary segment-wise longitudinal tumour extent, arterial and PV invasion, organ invasion (liver, pancreas, and duodenum), and regional lymph node metastasis were assessed on a five-point scale. Image performances were compared using the sensitivity, specificity, and area under the curve (AUC).

RESULTS

We included 120 patients (mean age, 71.7 ± 8.9; 84 males). The PV and liver differed most from the bile duct tumour in the portal phase. The abdominal aorta and pancreas differed most from eCCA in the arterial phase. For 80 patients evaluated on the five-point scale, adding phases increased the AUC for pancreatic, duodenal, and arterial invasion for each observer (observer 1, 0.79-0.93, p<0.01, 0.71-0.86, p = 0.04, 0.74-0.99, p = 0.02; observer 2, 0.88-0.96, p = 0.01, 0.73-0.94, p<0.01, 0.80-0.99 p = 0.04; respectively). The AUC for biliary segment-wise longitudinal tumor extent, hepatic, and PV invasion remained unchanged with additional phases.

CONCLUSIONS

Portal-phase information is sufficient to evaluate the segmental extent of bile duct and liver/PV invasion. Arterial- and delayed-phase information can help evaluate pancreatic, duodenal, and arterial invasion.

Urothelial-phase thin-section MDCT of the bladder in patients with hematuria: added value of multiplanar reformatted images

PURPOSE

To evaluate the diagnostic performance of MDCT with axial images and multiplanar reformatted (MPR) images from the urothelial phase of the bladder in patients with hematuria using cystoscopy as the reference standard.

MATERIALS AND METHODS

Our IRB for human investigation approved this study, and informed consent was waived. We included 192 patients (121 men, 71 women; age range 17-90 years; mean age ± SD: 60 ± 14 years) who underwent contrast-enhanced MDCT (scan delay: 70 s; section thickness: 2 mm) and conventional cystoscopy examination for painless gross hematuria or recurrent microscopic hematuria. Two radiologists in consensus interpreted the images for the presence or absence of bladder lesions. Using the kappa statistic, the patient-based agreement was determined between the CT and cystoscopic findings. We compared the diagnostic performance of axial images to those with coronal and sagittal reformations to detect bladder lesions.

RESULTS

MDCT showed excellent agreement between cystoscopy-axial scans (κ = 0.896) and axial with reformatted images (κ = 0.948). The sensitivity, specificity, and accuracy of MDCT were 94%, 96%, and 95% in the axial scans and 98%, 97%, and 97% in the axial with reformatted images, respectively. All statistical parameters of diagnostic performance were similar between the axial and the reformatted images (p > .05).

CONCLUSION

Axial MDCT imaging demonstrates high diagnostic performance in detecting bladder lesions, but additional reformatted images can improve diagnostic accuracy.

Current Status and Recent Update of Imaging Evaluation for Peri-Hilar Cholangiocarcinoma

간문주변부의 해부학적 복잡성으로 인해 간문주변부 담관암은 그 진단과 치료가 어려운 질환으로 알려져 있다. 간문주변부 담관암이 의심되는 환자에 있어서, 영상 검사는 이상 소견의 발견 및 감별 진단, 종양의 종축 침범 부위의 파악, 인접 혈관 침범과 원격 전이 유무의 파악, 그리고 최종적으로 수술적 절제 가능 유무의 평가에 있어 핵심적인 역할을 하고 있다. 이 종설에서는 간문주변부 담관암의 분류 및 종양의 평가를 위해 권고되는 표준 영상 검사의 기법과 간문주변부 담관암의 전형적인 영상 소견에 대해 기술할 예정이다. 종축 방향의 종양 침범 파악, 인접 혈관 침범 및 원격 전이 유무의 평가에 있어서 각 영상 검사 소견과 그 진단능에 대해 논의할 예정이다. 이후 전통적인 절제 가능성 평가의 개념에 대해 고찰하고, 최근의 경향을 소개한다.

Radiologic Evaluation and Structured Reporting Form for Extrahepatic Bile Duct Cancer: 2019 Consensus Recommendations from the Korean Society of Abdominal Radiology

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

Borderline resectable pancreatic cancer: conceptual evolution and current approach to image-based classification

Background

Diagnostic imaging plays a critical role in the initial diagnosis and therapeutic monitoring of pancreatic adenocarcinoma. Over the past decade, the concept of 'borderline resectable' pancreatic cancer has emerged to describe a distinct subset of patients existing along the spectrum from resectable to locally advanced disease for whom a microscopically margin-positive (R1) resection is considered relatively more likely, primarily due to the relationship of the primary tumor with surrounding vasculature.

Materials and methods

This review traces the conceptual evolution of borderline resectability from a radiological perspective, including the debates over the key imaging criteria that define the thresholds between resectable, borderline resectable, and locally advanced or metastatic disease. This review also addresses the data supporting neoadjuvant therapy in this population and discusses current imaging practices before and during treatment.

Results

A growing body of evidence suggests that the borderline resectable group of patients may particularly benefit from neoadjuvant therapy to increase the likelihood of an ultimately margin-negative (R0) resection. Unfortunately, anatomic and imaging criteria to define borderline resectability are not yet universally agreed upon, with several classification systems proposed in the literature and considerable variance in institution-by-institution practice. As a result of this lack of consensus, as well as overall small patient numbers and lack of established clinical trials dedicated to borderline resectable patients, accurate evidence-based diagnostic categorization and treatment selection for this subset of patients remains a significant challenge.

Conclusions

Clinicians and radiologists alike should be cognizant of evolving imaging criteria for borderline resectability given their profound implications for treatment strategy, follow-up recommendations, and prognosis.

Portal Vein/Aorta Ratio in Dogs with Acquired Portosystemic Collaterals

BACKGROUND

The portal vein (PV) diameter increases in humans with portal hypertension (PH). However, there is no evidence of PV enlargement in dogs with PH.

OBJECTIVES

To measure the PV-to-aorta (PV/Ao) ratio in dogs with PH (chronic hepatitis [CH], primary hypoplasia of the PV [PHPV]), in dogs with extrahepatic congenital portosystemic shunt (EH-CPSS), and in healthy dogs, and to evaluate the relationship between PV/Ao ratio and splenic pulp pressure (SPP).

ANIMALS

Twenty-five dogs with acquired portosystemic collaterals (APSCs; 15 with CH, 10 with PHPV), 32 dogs with EH-CPSS, and 20 healthy dogs.

METHODS

Retrospective study. The PV/Ao ratio was calculated with images obtained by computed tomography. SPP was measured at the time of liver biopsy in 45 dogs.

RESULTS

Median PV/Ao ratio was similar between dogs with CH (1.35, range 1.05-2.01) and healthy dogs (0.95, 0.80-1.15), but differed significantly between the CH group and both the PHPV (0.40, 0.24-0.67) and EH-CPSS groups (0.30, 0.11-0.64) (P < .001). The PV/Ao ratio was significantly lower in the PHPV group than in healthy dogs (P < .05). It also correlated positively with SPP (r_s = 0.71; P < .001). However, there was no intragroup correlation between SPP and the PV/Ao ratio in any group.

CONCLUSIONS AND CLINICAL IMPORTANCE

The PV/Ao ratio can be evaluated in dogs with APSCs on computed tomography. Further studies are needed to examine the relationship between SPP and the PV/Ao ratio in larger groups of dogs with PH and to determine its clinical relevance.

Portal Vein/Aorta Ratio in Dogs with Acquired Portosystemic Collaterals

Background

The portal vein (PV) diameter increases in humans with portal hypertension (PH). However, there is no evidence of PV enlargement in dogs with PH.

Objectives

To measure the PV‐to‐aorta (PV/Ao) ratio in dogs with PH (chronic hepatitis [CH], primary hypoplasia of the PV [PHPV]), in dogs with extrahepatic congenital portosystemic shunt (EH‐CPSS), and in healthy dogs, and to evaluate the relationship between PV/Ao ratio and splenic pulp pressure (SPP).

Animals

Twenty‐five dogs with acquired portosystemic collaterals (APSCs; 15 with CH, 10 with PHPV), 32 dogs with EH‐CPSS, and 20 healthy dogs.

Methods

Retrospective study. The PV/Ao ratio was calculated with images obtained by computed tomography. SPP was measured at the time of liver biopsy in 45 dogs.

Results

Median PV/Ao ratio was similar between dogs with CH (1.35, range 1.05–2.01) and healthy dogs (0.95, 0.80–1.15), but differed significantly between the CH group and both the PHPV (0.40, 0.24–0.67) and EH‐CPSS groups (0.30, 0.11–0.64) (P < .001). The PV/Ao ratio was significantly lower in the PHPV group than in healthy dogs (P < .05). It also correlated positively with SPP (r_s = 0.71; P < .001). However, there was no intragroup correlation between SPP and the PV/Ao ratio in any group.

Conclusions and Clinical Importance

The PV/Ao ratio can be evaluated in dogs with APSCs on computed tomography. Further studies are needed to examine the relationship between SPP and the PV/Ao ratio in larger groups of dogs with PH and to determine its clinical relevance.

Assessment of the renal corticomedullary (23)Na gradient using isotropic data sets

RATIONALE AND OBJECTIVES

(23)Na magnetic resonance imaging is a promising technique for the noninvasive imaging of renal function. Past investigations of the renal corticomedullary [(23)Na] gradient have relied on imaging only in the coronal plane and on cumbersome calculations of [(23)Na], which require the use of external phantoms. The aim of this study is therefore two-fold: to use an isotropic three-dimensional data set to compare coronal measurements of renal [(23)Na] relative to measurements obtained in planes along the corticomedullary gradients and to investigate cerebrospinal fluid (CSF) (23)Na signal as an internal reference standard, obviating the need for time-intensive [(23)Na] calculations.

MATERIALS AND METHODS

Nominal isotropic three-dimensional (23)Na MRI data sets were obtained in 14 healthy volunteers before and after a water load. Images were reconstructed in the coronal plane and in planes angled along the direction of the corticomedullary sodium gradients. [(23)Na] values and values of the corticomedullary [(23)Na] gradient were measured by placement of a linear region of interest along corticomedullary gradients in both the coronal/nonangled [(23)Na(non-ang)] and the angled [(23)Na(ang)] image reconstructions. CSF [(23)Na] was also acquired at multiple levels. Ratios of renal (23)Na and CSF (23)Na signal were calculated to construct a semiquantitative parameter, [(23)NaCSF]. Results of water stimulation as measured by [(23)NaCSF] and [(23)Na(ang)] were then compared.

RESULTS

Mean values of [(23)Na(ang)] were statistically significantly greater than those of [(23)Na(non-ang)] (P < .0001), although these values were linearly correlated (R = 0.553, P < .0001) and exhibited similar extents of decreases in absolute terms (P = .2) and in terms of the corticomedullary gradient following the water load. CSF [(23)Na] did not statistically significantly differ at any level after the water load (P > .5) but tended to increase in the cranial direction (P < .001). [(23)NaCSF] measures demonstrated analogous statistical properties to [(23)Na(ang)] before and after the water load.

CONCLUSIONS

Assessment of renal corticomedullary [(23)Na] gradients using isotropic data sets with image reconstructions along the gradients is likely more accurate than measurements in the coronal plane. Because CSF [(23)Na] differs based on anatomic levels, such measures are useful as an internal reference only if region of interest placement is consistent. With this caveat in mind, normalization of renal to CSF (23)Na signal provides a feasible, less cumbersome alternative to [(23)Na] calculations in intraindividual studies.

Comparison of three-dimensional negative-contrast CT cholangiopancreatography with three-dimensional MR cholangiopancreatography for the diagnosis of obstructive biliary diseases

PURPOSE

The purpose of our study was to compare three-dimensional (3D) negative-contrast CT cholangiopancreatography (3D-nCTCP) with 3D MR cholangiopancreatography (3D-MRCP) for the diagnosis of obstructive biliary diseases.

MATERIALS AND METHODS

3D-nCTCP and 3D-MRCP were performed on seventy clinically documented obstructive biliary diseases patients. The accuracy of each technique in determining the location and cause of biliary obstruction was evaluated compared with the final clinical diagnoses.

RESULTS

Both methods achieved 100% of accuracy in the diagnosis of the presence and location of biliary obstruction, and had a similar sensitivity, specificity, accuracy in differentiating benign from malignant biliary obstruction or calculous from noncalculous biliary obstruction (p>0.05). At 3D-nCTCP, six patients with stones were misinterpreted as cholangitis (N=2), papillitis (N=3), or bile duct adenocarcinoma (N=1); two metastases were mistaken as acute pancreatitis or pancreatic head carcinomas, and one intrahepatic cholangiocarcinoma was misled as bile duct adenoma. At 3D-MRCP, one small stone, one ampullary adenoma, and one intrahepatic cholangiocarcinoma were mistaken as cholangitis, ampullary stone, and intrahepatic bile duct stone, respectively, and three gallbladder carcinomas and another intrahepatic cholangiocarcinoma were misdiagnosed as hilar cholangiocarcinoma (N=3) or common hepatic duct stone (N=1); four metastases were mistaken as pancreatic head carcinomas (N=3) or distal cholangiocarcinoma (N=1). The overall accuracy in making specific diagnosis of the cause of biliary obstruction was 87.1% for 3D-nCTCP and 84.3% for 3D-MRCP, respectively, (p>0.05).

CONCLUSION

3D-nCTCP has the similar effects as 3D-MRCP for the diagnosis of biliary obstruction and, the location and the cause of biliary obstruction. In view of selected cases contraindications for MRI, 3D-nCTCP is a potential substitute.

Update on 3D and multiplanar MDCT in the assessment of biliary and pancreatic pathology

The development of multidetector row computed tomography (MDCT) has led to the acquisition of true isotropic voxels that can be postprocessed to yield images in any plane of the same resolution as the original axially acquired images. This, coupled with rapid MDCT imaging during peak target organ enhancement has led to a variety of means to review imaging information beyond that of the axial perspective. Postprocessing can be utilized to identify variant biliary anatomy to guide preoperative planning of biliary-related surgery, determine the level and cause of biliary obstruction and assist in staging of biliary cancer. Postprocessing can also be used to identify pancreatic ductal variants, visualize diagnostic features of pancreatic cystic lesions, diagnose and stage pancreatic cancer, and differentiate pancreatic from peripancreatic disease.

Quantitative preoperative assessment of vascular involvement in pancreatic carcinoma by multi-detector row computer tomography

AIM: To evaluate the clinical efficacy of multi-detector row computer tomography (MDCT) in the preoperative quantitative assessment of vascular involvement of pancreatic carcinoma.

METHODS: MDCT was performed on 42 pancreatic carcinoma patients; the celiac trunk and portal vein were reconstructed and their branches to three-dimension vessel were analyzed by volume rendering (VR) technique, multiplanar volume reconstruction (MPVR) and maximum intensity projection (MIP) technique. Combining the source images, the scope and extent of the vessel invaded in the portal vein celiac trunk, and inferior vena cava and their branches were evaluated and measured. Compared the CT scans results with operations and pathological sections, the diagnosis value of MDCT for pancreatic carcinoma was evaluated.

RESULTS: In the 42 pancreatic carcinoma patients with operation, 252 vessels were evaluated, 77 of which were invaded by carcinoma. Celiac trunks were invaded in 12 patients, and the sensitivity and specificity were 84.6% and 96.6%, respectively. Superior mesenteric arteries were invaded in 13 patients, and the sensitivity and specificity were 100% and 96.7%, respectively. Hepatic arteries were invaded in 9 patients, and the sensitivity and specificity were 81.2% and 100%, respectively. Portal veins were invaded in 16 patients, and the sensitivity and specificity were 93.3% and 92.6%, respectively. Inferior vena cava was invaded in 6 patients, and the sensitivity and specificity were 93.3% and 92.6%, respectively. Superior mesenteric veins were invaded in 21 patients, and the sensitivity and specificity were 90% and 86.7%, respectively. In the aspect of thrombosis, MDCT scan results were consistent with the surgical findings. Only one vessel of superior mesenteric artery and vein was not correctly measured in length by MDCT. When the length between invaded vessel and vessel branches was measured, only one patient's MDCT result was consistent with the surgical result on superior mesenteric artery.

CONCLUSION: MDCT can delineate the vascular involvement of pancreatic carcinoma with high accuracy, measure the invaded vessel correctly and provide valuable information for the preoperative assessment of pancreatic carcinoma.