Three-dimensional computed tomography angiography reconstruction of the origin of the uterine artery and its clinical significance.

PURPOSE: In women, the uterine artery is the main branch of the internal iliac artery, vascularizing most of the uterus. Knowledge of its origin and variations is essential during extensive gynaecological surgery and interventional radiological procedures. We aimed to investigate its origin and explore its anatomical variations by three-dimensional (3D) reconstructed computed tomography (CT) angiography. METHODS: This was a retrospective, monocentric observational study involving CT scans of the abdomen and lower limbs of women < 50 years old with 3D reconstructed CT images of the internal and external iliac arterial axes. RESULTS: Between 01 January 2014 and 31 December 2015, among 986 cases of CT scans performed in women, for all indications, 3D reconstructed images for 43 women could be analysed. The uterine artery originated from a common trunk with the umbilical artery in 62.7% of cases, from a direct branch of the internal iliac artery in 25.6% of cases, directly from the superior gluteal artery in 9.3% of cases and from the internal pudendal artery in 2.3%. CONCLUSIONS: Three-dimensional(3D) reconstructed CT angiography can detect the point of origin of the uterine artery. Therefore, it can be used as a mapping tool of the pelvic arterial tree. Our study corroborates data from the literature that the uterine artery most often originates from a common trunk with the umbilical artery. However, surgeons and intervention radiologists must be aware of the variability of its origin to facilitate the safety of the patients during procedures.

Imaging review of hepatocellular carcinoma after thermal ablation: The good, the bad, and the ugly.

Image-guided thermal ablation is a well-established locoregional technique for the treatment of hepatocellular carcinoma (HCC). HCC surveillance programs have led to an increase in the number of patients diagnosed at an early stage of the disease who are eligible for thermal ablation. Tumor response is assessed on imaging and requires extensive follow-up; thus, radiologists play a key role in defining the technical success and efficacy of treatment as well as identifying progressive disease. Although they are rare, complications, such as secondary infections, must also be identified. Several contrast-enhanced imaging techniques can be used at different postprocedural timepoints but magnetic resonance imaging (MRI) and computed tomography (CT), which allow both liver-centered and whole-body imaging are the cornerstones of follow-up. This review describes the imaging features of HCC following thermal ablation. After describing the basic technical elements of follow-up imaging, imaging findings are divided into three groups: normal and expected features (the good), abnormal features, uncontrolled disease, and complications (the bad), and atypical or rare presentations (the ugly). J. Magn. Reson. Imaging 2016;44:1070-1090.

Hepatic and perihepatic involvement of female genital diseases and pregnancy: a review.

The liver is rarely involved in female genital diseases or pregnancy. Peripheral hepatic and perihepatic lesions are mainly due to the progression of genital malignancies, usually ovarian cancer. It should be distinguished from other malignant and non-malignant lesions. In all clinical situations, liver involvement is a sign of distant extension or dissemination of female genital diseases. Therefore, accurate detection and characterization of hepatic and perihepatic involvement on imaging is of clinical importance and often changes patient management.

Accuracy and disagreement of computed tomography and magnetic resonance imaging for the diagnosis of small hepatocellular carcinoma and dysplastic nodules: role of biopsy.

UNLABELLED: Liver macronodules, ranging from benign to low-grade or high-grade dysplastic nodules (LGDNs/HGDNs) and hepatocellular carcinoma (HCC), may develop during chronic liver diseases (CLDs). Current guidelines were recently updated and the noninvasive criteria for the diagnosis of small HCC are based on a single typical radiological pattern and nonconclusive coincidental findings with two techniques. This study aimed to assess the accuracy and disagreements of noninvasive multiphasic examinations for the diagnosis of HCC and dysplastic nodules (DNs) and the role of biopsy. Seventy-four consecutive patients with CLD with ultrasound-detected 1-2-cm nodules underwent, within 1 month, multiphasic computed tomography (CT), magnetic resonance imaging (MRI), and biopsy of the nodule. Median age was 60 years; 33 patients (45%) had hepatitis C virus, 20 (27%) had hepatitis B virus, and 13 (18%) patients had no cirrhosis. Biopsy revealed 47 HCCs, 6 HGDNs, 1 LGDNs, 1 cholangiocarcinoma, and 1 epithelioid hemangioendothelioma. There were no tumors in the other 18 patients. All patients (31 of 31; 100%) who had conclusive coincidental findings (i.e., arterial enhancement and washout) on both examinations had HCC or HGDN (sensitivity, 57%; specificity, 100%). All patients (51 of 51; 100%) who had conclusive findings on at least one of the two examinations had HCC or HGDN (sensitivity, 96%; specificity, 100%). There was a disagreement regarding imaging findings between CT and MRI in 21 of 74 (28%) patients and no washout on both examinations in 23 of 74 patients (31%). In these 44 patients, liver biopsy provided an initial accurate diagnosis. CONCLUSION: The noninvasive diagnosis of HCC or HGDN can be obtained if arterial enhancement and washout are found in a single dynamic imaging examination. These findings are frequently discordant on both CT and MRI, supporting the place of biopsy for the diagnosis of small HCCs.

Comparison of FDG-PET/CT and MR with diffusion-weighted imaging for assessing peritoneal carcinomatosis from gastrointestinal malignancy.

OBJECTIVES: To assess the accuracy of FDG-PET/CT and MR with diffusion-weighted imaging (MR-DWI) for diagnosing peritoneal carcinomatosis (PC) from gastrointestinal malignancies. METHODS: Thirty consecutive patients referred for staging of gastrointestinal malignancy underwent FDG-PET/CT and MR-DWI in this retrospective study. Extent of PC was characterised by dividing the peritoneal cavity into three sites in each patient: right and left supramesocolic areas and inframesocolic level (total 90 sites). Presence of PC was confirmed either by surgery (18/30) or by follow-up (12/30). RESULTS: PC was confirmed in 19 patients (19/30). At a total of 90 sites, 27 showed proven PC. On a patient-based analysis, sensitivity, specificity, PPV, NPV and accuracy were respectively 84%, 73%, 84%, 73% and 80% for PET/CT and 84%, 82%, 89%, 75% and 83% for MR-DWI. On a site-based analysis, overall sensitivity and specificity of PET/CT (63%, 90%) and MR-DWI (74%, 97%) were not statistically different (P = 0.27). In the supramesocolic area, MR-DWI detected more sites involved than PET/CT (7/9 vs. 4/9). The sensitivities of PET and MR were lower for subcentimetre tumour implants (42%, 50%). Interobserver agreement was very good for PET/CT and good for MR-DWI. CONCLUSIONS: FDG-PET/CT and MR-DWI showed similar high accuracy in diagnosing PC. Both techniques underestimated the real extent of PC because of decreased sensitivity for subcentimetre lesions. KEY POINTS: FDG-PET/CT and MR-DWI showed similar high accuracy for diagnosing peritoneal carcinomatosis. • In the supramesocolic area, MR-DWI could be more sensitive than PET/CT. • Both techniques showed lower sensitivity for subcentimetre lesions. • Interobserver agreement was very good for PET/CT and good for MR-DWI.

New MR imaging criteria with a diffusion-weighted sequence for the diagnosis of hepatocellular carcinoma in chronic liver diseases.

BACKGROUND & AIMS: To propose MRI criteria with a diffusion-weighted imaging (DWI) sequence for the diagnosis of hepatocellular carcinoma (HCC). METHODS: Patients, who underwent liver MRI with contrast-enhanced sequences and DWI between 2004 and 2008 and who had at least one confirmed HCC of at least 10mm, were included. Index diagnostic criteria were: (1) enhancement in the arterial-dominant phase and washout in the portal venous and/or equilibrium phases; (2) enhancement in the arterial-dominant phase and hyperintensity on DWI; (3) enhancement in the arterial-dominant phase and washout in the portal venous and/or equilibrium phases or hyperintensity on DWI. Two radiologists independently reviewed the corresponding sets of sequences (DWI alone; T1-weighted sequence before and after dynamic injection of gadolinium chelates; combined DWI-T1-weighted sequence). Inter-observer agreement and sensitivity were determined per nodule. RESULTS: Ninety-one patients were included (109 HCCs). The sensitivity of conventional MRI criteria for the diagnosis of HCC was 59.6% for both radiologists. The sensitivity of enhancement in the arterial-dominant phase and hyperintensity on DWI was 77.1% or 76.1%, depending on the radiologist. The sensitivity of enhancement in the arterial-dominant phase and washout in the portal venous and/or equilibrium phases or hyperintensity on DWI was 84.4% or 85.3%, depending on the radiologist. The inter-observer agreement for the latter was very good (kappa coefficient 0.82). These results were consistent in HCCs smaller than 20mm. CONCLUSIONS: The proposed criteria, based on the characteristics of lesions after gadolinium chelate administration and hyperintensity on DWI, significantly increased the sensitivity for the diagnosis of HCC compared to conventional criteria, regardless of tumor size.

Factors Associated with Tumor Progression After Percutaneous Ablation of Hepatocellular Carcinoma: Comparison Between Monopolar Radiofrequency and Microwaves. Results of a Propensity Score Matching Analysis.

PURPOSE: To identify risk factors for local and distant intrahepatic tumor progression after percutaneous ablation of HCC and to compare MWA with monopolar RFA. MATERIALS AND METHODS: Consecutive patients with early or very early HCC who underwent percutaneous monopolar RFA or MWA were included. Factors associated with local and distant tumor progression were identified. Propensity score matching (PSM) was used to limit bias. Statistical analyses were performed with the Kaplan-Meier method using the log-rank test and Cox regression models. RESULTS: One hundred ninety HCC (mean diameter 23 ± 8.6 mm) were treated by RFA (n = 90, 47%) or MWA (n = 100, 53%) in 152 patients (mean age 63 ± 11, 79% men) between 2009 and 2016. The technical success rate was 97.4% (n = 185 HCC). After a median follow-up of 24.6 months (IQR: 9.7-37.2), 43 (23%), HCC showed local tumor progression [after a median of 13.4 months (IQR: 5.8-24.3)] and 91 (63%) patients had distant intrahepatic tumor progression (after a median of 10.4 months (IQR: 5.7-22). The cox model after PSM identified treatment by RFA (HR, 2.89; P = 0.005), HCC size ≥ 30 mm (HR, 3.12; P = 0.007) and vascular contact (HR, 3.43; P = 0.005) as risk factors for local progression. Factors associated with distant intrahepatic progression were HCC ≥ 30 mm (HR, 1.94; P = 0.013), serum AFP > 100 ng/mL (HR, 2.56; p = 0.002), and hepatitis B carrier (HR, 0.51; p = 0.047). CONCLUSION: The rate of local HCC progression was lower after MWA than monopolar RFA, regardless of tumor size and vascular contact. The ablation technique did not influence the risk of distant intrahepatic tumor progression.

Fatty hepatocellular carcinoma: radiofrequency ablation--imaging findings.

PURPOSE: To describe the imaging features during follow-up after radiofrequency (RF) ablation of fat-containing hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Institutional review board approval was obtained; informed consent was waived. A retrospective search in an electronic radiologic archive was performed for a 40-month period between February 2004 and May 2007 to identify patients who had undergone RF ablation of fat-containing HCCs. The presence of intratumoral fat was determined at imaging (magnetic resonance or computed tomography) prior to the RF procedure; eight fat-containing HCCs, which had a mean size of 25 mm (range, 20-30 mm), were found. Images during follow-up were reviewed and compared with images prior to RF ablation to determine changes in fat content, complete or partial ablation, and local tumor progression. Tumor response was on the basis of assessment of lesion characteristics and enhancement for a follow-up of at least 6 months. RESULTS: Persistent fat content was found at imaging in all ablation zones. Six patients were considered to have completely ablated tumors (mean follow-up, 16 months; range, 6-29 months), and two patients had local progression (mean follow-up, 18 months; range, 14-22 months). In the ablation zone of completely ablated tumors, the fat content progressively decreased (n = 4) or was unchanged during follow-up (n = 2). In the two tumors with local progression, the fat portion enlarged (n = 1) or did not change after ablation (n = 1). CONCLUSION: Persistence of fat in the ablation zone during imaging follow-up after RF ablation of fat-containing HCCs does not necessarily indicate treatment failure. Changes in fat content of the ablation zone during follow-up (increase or decrease in size) could be used as additional criteria to determine success or failure of RF ablation in fat-containing HCC.

Utility of CT in the diagnosis of pancreatic fistula after pancreaticoduodenectomy in patients with soft pancreas.

OBJECTIVE: The purpose of this study was to evaluate the sensitivity and specificity of routine performance of CT on postoperative day 7 in patients at high risk of pancreatic fistula after pancreaticoduodenectomy. MATERIALS AND METHODS: Two radiologists analyzed images from CT examinations of 50 patients with soft pancreas 7 days after pancreaticoduodenectomy. Pancreatic fistula was defined at CT as a fluid collection close to the pancreaticogastric or pancreaticojejunal anastomosis. Clinicobiologic criteria for the diagnosis of pancreatic fistula were drain output of any measurable volume of fluid on or after postoperative day 3 that had an amylase content more than three times the serum amylase activity. The final diagnosis of pancreatic fistula was rendered on the basis of clinicobiologic data at hospital discharge or at first readmission. RESULTS: At hospital discharge or at first readmission, 27 of 50 patients (54%) had a pancreatic fistula. On postoperative day 7, 30 patients (60%) had a total of 51 fluid collections, and CT showed a fluid collection close to the pancreaticogastric or pancreaticojejunal anastomosis in 21 of 51 cases. CT had a sensitivity of 63% (17/27 patients) and a specificity of 83% (19/23 patients) for the diagnosis of pancreatic fistula with four false-positive and 10 false-negative findings. The diagnosis of pancreatic fistula on the basis of clinicobiologic criteria on postoperative day 7 was made in 22 of 27 patients (81%), whereas five cases were false-negative. Four of these patients had CT evidence of pancreatic fistula. CONCLUSION: In patients at high risk who have undergone pancreaticoduodenectomy, systematic postoperative CT may be proposed as a complementary tool in the diagnosis of pancreatic fistula, particularly for detection of clinically occult pancreatic fistula.

Late onset of nivolumab-induced severe gastroduodenitis and cholangitis in a patient with stage IV melanoma.

Antiprogramed cell death-1 protein agents represent a therapeutic approach based on stimulating the host's immune response through blockade of immune checkpoints, inhibitory pathways that dampen the physiological peripheral T-cell immune response and are essential for maintaining self-tolerance. We describe the late onset of severe gastroduodenitis and cholangitis in a nivolumab-treated, metastatic melanoma patient in complete remission. Positron-emission tomography with computed tomography scans showed diffuse fluorodeoxyglucose (FDG) uptake in the stomach preceding upper digestive tract symptoms. Hence, positron-emission tomography with computed tomography might as well be a useful tool for early diagnosis of subclinical gastric toxicity as recently shown for colitis. Furthermore, physicians must be aware and remain vigilant to antiprogramed cell death-1 protein-related digestive toxicity that may appear very late during treatment.

Determination of a Central Avascular Triangle within the Obturator Foramen: A Radioanatomic Study.

PURPOSE: To map the vascular anatomy of the obturator foramen using fixed anatomic landmarks. METHOD: Twenty obturator regions were dissected in 10 fresh female cadavers after vascular blue dye injection in five cadavers (50%). Furthermore, 104 obturator regions were reconstructed by angiotomodensitometry from 52 women under investigation for suspected arterial disease. The anatomy of the obturator region was mapped by measuring the distance of vascular structures from the middle of the two branches of the ischiopubic bone, which were used as fixed landmarks. RESULTS: The bifurcation of the obturator artery was at a mean (SD) distance of 30.0 mm (4.5) from the middle of the ischiopubic branch (MISP). The anterior branch of the obturator vessels was 15.2 mm (10.1) from the MISP. The posterior branch of the obturator vessels was 5.5 mm (4.0) and 23.6 mm (8.7) from the middle of the outer edge of the obturator foramen (MOE) and the MISP, respectively. Using 5° and 95° percentiles of these measurements we defined a central avascular triangle. CONCLUSIONS: Our data show that, beyond inter-individual variations, a central triangular avascular area can be identified in the obturator foramen between the posterior and anterior obturator artery using fixed landmarks.

[Radiofrequency ablation of hepatic tumors]. / Ablación por radiofrecuencia de tumores hepáticos.

This article aims to review the state of the art in ablation techniques for hepatic lesions. In addition to discussing the indications, outcomes, and potential complications of the technique, we illustrate the spectrum of imaging findings after treatment. Recent years have seen the development of a wide variety of minimally invasive techniques to treat liver cancer. These include ethanol injection, and thermal ablation using radiofrequency, laser, microwaves, or cryosurgery. Percutaneous radiofrequency ablation is one of the most promising non-surgical treatments for hepatic neoplasms. The results of several studies show that radiofrequency ablation enables adequate local control of tumors with few complications, achieving acceptable survival rates. Radiofrequency ablation can be performed using any imaging technique, although it is most commonly performed under ultrasound guidance. CT and MRI show the degree of tumor necrosis better and are more frequently employed in follow up. This article reviews the indications and contraindications for the procedure, potential complications, long-term outcome, and imaging findings for percutaneous radiofrequency ablation of hepatic tumors.

Ablación por radiofrecuencia de tumores hepáticos / Radiofrequency ablation of hepatic tumors

El objetivo de este artículo es la revisión del estado actual de las técnicas de ablación hepáticas, sus indicaciones y resultados, además de ilustrar el espectro de hallazgos radiológicos tras un tratamiento adecuado, así como las complicaciones potenciales que pueden producirse. En los últimos años se han desarrollado una gran variedad de tratamientos contra el cáncer mínimamente invasivos, entre los que se incluyen la inyección de etanol, así como técnicas de ablación termal con radiofrecuencia, láser, microondas o criocirugía. La ablación percutánea con radiofrecuencia es uno de los tratamientos no-quirúrgicos de las neoplasias hepáticas más prometedores. Los resultados de varios estudios muestran que la ablación por radiofrecuencia permite un adecuado control local tumoral con pocas complicaciones y que consigue tasas de supervivencia aceptables. La ablación por radiofrecuencia puede realizarse con cualquier técnica de imagen, pero generalmente es la ecografía la más utilizada como guía para el procedimiento mientras que la tomografía computarizada (TC) y la resonancia magnética (RM) valoran más adecuadamente el grado de necrosis tumoral. En este artículo revisaremos las indicaciones y contraindicaciones para la realización del procedimiento, las complicaciones potenciales que pueden producirse, los resultados a largo plazo y los hallazgos por imagen

This article aims to review the state of the art in ablation techniques for hepatic lesions. In addition to discussing the indications, outcomes, and potential complications of the technique, we illustrate the spectrum of imaging findings after treatment. Recent years have seen the development of a wide variety of minimally invasive techniques to treat liver cancer. These include ethanol injection, and thermal ablation using radiofrequency, laser, microwaves, or cryosurgery. Percutaneous radiofrequency ablation is one of the most promising non-surgical treatments for hepatic neoplasms. The results of several studies show that radiofrequency ablation enables adequate local control of tumors with few complications, achieving acceptable survival rates. Radiofrequency ablation can be performed using any imaging technique, although it is most commonly performed under ultrasound guidance. CT and MRI show the degree of tumor necrosis better and are more frequently employed in follow up. This article reviews the indications and contraindications for the procedure, potential complications, long-term outcome, and imaging findings for percutaneous radiofrequency ablation of hepatic tumors