Maria Chiara Ambrosetti

Single-energy low-voltage arterial phase MDCT scanning increases conspicuity of adenocarcinoma of the pancreas.

PURPOSE To test a single-energy low-voltage CT protocol for pancreatic adenocarcinoma. METHODS AND MATERIALS A total of 30 patients with pathology-proven pancreatic adenocarcinoma underwent 64-row MDCT with arterial phase at 80 kV and were compared to a similar group of 30 patients scanned with a 120 kV protocol. Scans were compared for quantitative image parameters (attenuation and standard deviation in the pancreas, tumor, aorta), CTDI and DLP using an unpaired t-test. Image noise values for each protocol (SD of the psoas) were compared using an unpaired t-test. Effective dose was calculated for each protocol. CNR (=conspicuity/SDnoise) and FOM (CNR2/ED) were calculated. The Catphan600 phantom was used to evaluate image non-uniformity, noise, spatial resolution, and low contrast detectability. RESULTS Mean patient weight was 68 kg in the study group and 73 kg in the control group (p=0.0355), while patient diameters at the celiac axis were not significantly different. Mean attenuation was significantly higher at 80 kV in the aorta (517.5±116.4 vs 290.3±76.4 HU) and normal pancreas (154.0±39.95 vs 90.02±19.01 HU) (all p<0.0001), while no significant difference was observed for adenocarcinoma (61.43±35.61 vs 47.45±18.95; p=n.s.). CTDI and DLP were significantly lower at 80 kV (6.00±0.90 mGy vs 10.24±2.93 mGy, and 180.4±35.49 mGy cm vs 383.8±117 mGy cm, respectively; all p<0.0001). Tumor conspicuity (HUpancreas-HUtumor) was significantly higher at 80 kV (94.2±39.3 vs 39.5±22 HU; p<0.0001). Mean image noise was significantly higher at 80kV (28.32±10.06 vs 19.7±7.1HU; p<0.0001). Effective dose was significantly lower at 80 kV (1.984±0.39 vs 5.75±1.75 mSv; p<0.0001). The total DLP for the exam was 1024±31.86 mGy cm for the 80 kV protocol and 1357±62.60 mGy cm for the 120 kV protocol (p<0.0001). Phantoms showed higher non-uniformity, slightly higher noise, slightly lower MTF (50%) and slightly higher percentage contrast for the 80 kV protocol. CONCLUSION Single-source 80 kV pancreatic phase scanning results in higher conspicuity of pancreatic adenocarcinoma and FOM and in significant dose reduction while maintaining acceptable image quality.

Virtual autopsy using multislice computed tomography in forensic medical diagnosis of drowning

PurposeThis study evaluated the usefulness of multidetector computed tomography (MDCT) in the postmortem diagnosis of death by drowning in fresh water by measuring the difference of blood density within the cardiac chambers.Materials and methodsTwenty-two corpses including six cases of fresh-water drowning (group A) and 16 deaths by other causes (group B), among which were also different forms of mechanical asphyxia other than drowning, underwent MDCT and conventional autopsy. Blood density within the right and left heart chambers, the aorta and the pulmonary trunk was measured and values compared between groups and within each group between heart chambers.ResultsBlood density in all cardiac chambers was lower in group A than in group B. The difference was statistically significant within the left atrium and ventricle and was significantly lower in the left than in the right heart chambers in group A only.ConclusionsMDCT, together with conventional autopsy, may contribute to the diagnosis of drowning, by measuring blood density in the heart chambers.RiassuntoObiettivoValutare se l’impiego della tomografia computerizzata multistrato (TCMS) possa essere d’aiuto nella diagnosi di morte per annegamento in acqua dolce tramite misura della differenza di concentrazione ematica all’interno delle camere cardiache.Materiali e metodiSono stati sottoposti a TCMS ed esame autoptico convenzionale 22 cadaveri, di cui 6 morti per annegamento in acqua dolce (gruppo A) e 16 per altre cause (gruppo B), tra le quali erano presenti anche asfissie meccaniche diverse dall’annegamento. è stata misurata la densità del sangue all’interno delle camere cardiache di destra e sinistra, dell’aorta e del tronco polmonare e confrontati i valori tra i due gruppi e all’interno di ogni gruppo tra le camere cardiache.RisultatiLa densità ematica all’interno di tutte le camere cardiache è risultata inferiore nel gruppo A rispetto al gruppo B. La differenza è risultata statisticamente significativa all’interno di atrio e ventricolo di sinistra. La densità ematica è risultata significativamente inferiore nelle camere cardiache di sinistra rispetto quelle di destra solo nel gruppo A.ConclusioniLa TCMS può essere impiegata per la misura della densità ematica nelle camere cardiache per la diagnosi di morte da annegamento in acqua dolce in ausilio all’esame autoptico convenzionale.

Ultrasonography of the Pancreas

Although the pancreas is often thought of as an organ that is difficult to explore using ultrasound (US), because of its deep retroperitoneal location, with the appropriate technique it can be studied successfully in most patients. In this article, the authors discuss the use of available US techniques in the diagnosis of the most common pancreatic diseases, the use of US intraoperatively, and the use of sonographic guidance for diagnostic and therapeutic procedures. The authors also briefly discuss the potential use of elastosonography techniques in the evaluation of pancreatic disease.

Autoimmune pancreatitis and non-necrotizing acute pancreatitis: computed tomography pattern.

OBJECTIVES To retrospectively differentiate diffuse autoimmune pancreatitis from non-necrotizing acute pancreatitis at clinical onset with multi detector row computed tomography. METHODS 36 Patients suffering from diffuse autoimmune pancreatitis (14) or non-necrotizing acute pancreatitis (22) were enrolled. Qualitative analysis included stranding, retroperitoneal fluid film, capsule-like rim enhancement and pleural effusion. In quantitative analysis pancreatic density was measured in all phases. The vascularization behaviour was assessed using the relative enhancement rate across all phases. RESULTS Pancreatic density resulted lower in non-necrotizing acute pancreatitis compared to diffuse autoimmune pancreatitis patients in pre-contrast phase and higher in pancreatic phase. Relative enhancement rate evaluation confirmed different vascularization behaviours of the two diseases. Only non-necrotizing acute pancreatitis Patients presented peripancreatic stranding and fluid in the retromesenteric interfascial plane. CONCLUSIONS Multi detector row computed tomography is a useful technique for differentiating diffuse autoimmune pancreatitis from non-necrotizing acute pancreatitis at clinical onset. Peripancreatic stranding and retroperitoneal fluid film, characteristic of non-necrotizing acute pancreatitis, and late-phase peripheral rim enhancement, characteristic of diffuse autoimmune pancreatitis, provide qualitative clues to the differentiation. A quantitative study of contrast enhancement patterns, considering the relative enhancement rate, can assist in the differential diagnoses of two diseases.

Solid non-functioning endocrine tumors of the pancreas: correlating computed tomography and pathology

BACKGROUND Since prognosis and treatment of pancreatic endocrine tumors (pNET) are based on tumor grade, contrast-enhanced multidetector computed tomography (MDCT) features of solid non-functioning pNETs were studied and correlated with pathology tumor grading. METHODS MDCTs of diagnosed pNETs were reviewed retrospectively. Each tumor was analyzed for location, size, homogeneity, margins, arterial and venous phase enhancement, main pancreatic duct diameter, calcifications, vascular invasion, lymph-nodes enlargement, and liver metastases. RESULTS Of 154 pNETs presenting between January 2000 and May 2016 with available histology from resected specimen or biopsy, there were 65 G1, 72 G2 and 17 G3 pNETs. Tumor diameter varied significantly between the three groups. Tumors >20 mm were more frequently malignant and non-homogeneous than smaller tumors. G1 tumors were more commonly hypervascular and G3 tumors more often non-hypervascular in the arterial phase. Arterial phase non-hyperdensity and tumor non-homogeneity had a higher rate of metastatic lesions. Vascular invasion correlated with presence of metastases and histological grade. G3 tumors were all >20 mm (p = 0.007), more often non-hypervascular in the arterial phase (p = 0.0025), and non-hyperdense in the venous phase (p = 0.009), and showed more often vascular invasion (p = 0.0198). CONCLUSION CT correlated with tumor grade; differentiating low-grade and high-grade pNETs through routine CT imaging might improve patient management.

Solid Pseudopapillary Neoplasms

Solid pseudopapillary tumor is a rare low grade malignant pancreatic tumor that occurs mainly in women (85-90%). The wide variability of histological features of SPNs reflects on the imaging findings, from completely solid tumors to almost completely cystic masses. Smaller masses are usually completely or mostly solid, while larger lesions typically present as large well-encapsulated masses with varying solid and cystic components caused by hemorrhagic degeneration. When lesions are entirely or partially cystic, especially for larger lesions, MRI can be more useful in depicting features that are helpful for the diagnosis, such as intra-tumoral hemorrhage and the peripheral enhancement pattern.

Mucinous Carcinoma and IPMN

Mucin-producing tumors of the pancreas represent a group of premalignant or malignant neoplasms forming multilocular cysts and lined by tall, columnar mucinous epithelium. These tumors are broadly divided into mucinous cystic neoplasms (MCN) and intraductal papillary mucinous neoplasms (IPMN) which have different biologic behavior and pathologic features, including prevalence of invasive cancer, recurrence rate after radical resection, and presence of multifocal lesions. For these reasons a deep knowledge of the imaging features and preferential pathways of local or distal tumor spread focusing on parenchymal, vascular, nodal, perineural, and peritoneal dissemination may improve the radiologist’s confidence when assessing these diseases.

CT features of non-hypervascular endocrine tumours of the pancreas: a comparison with pancreatic adenocarcinoma

Purpose: To gather opinions of radiographers regarding the use of humour among students and professionals, and to apprehend possible positive and/or negative impacts of its use on the care relationship. Methods: Sample. Six hundred forty-one senior radiographers and 411 first, second or third year undergraduate radiographers, for a total sample of 1052 subjects from all over France. Material. Within a quantitative phase, both professionals radiographers and radiographers-in-training were assessed on several Likert-type scales involving concepts such as the functions of humour, and a second, qualitative phase based on open survey questions further focused on investigating the most salient concepts, notably within the senior radiographer sample. Results: Although radiographer apprentices saw the major benefits of humour in their relationships with patients (i.e. building a trust relationship, distraction technique), the senior radiographers put forward benefits especially regarding their colleagues or their own person (pleasant working environment, coping strategy during stressful events). Positive aspects of humour do prevail over the negative ones in both radiographer groups, but professionals emphasize the contextualized aspects of humour and warn that it may infringe on patients and their dignity. Conclusion: Considering humour as a personal and a professional value among the samples studied opens new perspectives on use of humour and its training within both institutional and educational contexts, preventing any possible harmful use.

Correlation between appearance of the retroportal fat plane at preoperative CT and pathology findings in resected adenocarcinoma of the pancreatic head

Purpose: To gather opinions of radiographers regarding the use of humour among students and professionals, and to apprehend possible positive and/or negative impacts of its use on the care relationship. Methods: Sample. Six hundred forty-one senior radiographers and 411 first, second or third year undergraduate radiographers, for a total sample of 1052 subjects from all over France. Material. Within a quantitative phase, both professionals radiographers and radiographers-in-training were assessed on several Likert-type scales involving concepts such as the functions of humour, and a second, qualitative phase based on open survey questions further focused on investigating the most salient concepts, notably within the senior radiographer sample. Results: Although radiographer apprentices saw the major benefits of humour in their relationships with patients (i.e. building a trust relationship, distraction technique), the senior radiographers put forward benefits especially regarding their colleagues or their own person (pleasant working environment, coping strategy during stressful events). Positive aspects of humour do prevail over the negative ones in both radiographer groups, but professionals emphasize the contextualized aspects of humour and warn that it may infringe on patients and their dignity. Conclusion: Considering humour as a personal and a professional value among the samples studied opens new perspectives on use of humour and its training within both institutional and educational contexts, preventing any possible harmful use.

Neoplasms of the Ovary

Adnexal masses (AMs) are common findings among both premenopausal and postmenopausal women. The main goals of an initial diagnostic work-up for an AM are to rule out malignancy and to differentiate between AM requiring surgical intervention and those that can be managed conservatively. Among the gynecological sources, diagnostic entities can be broadly separated into functional or physiological, inflammatory, or neoplastic lesions. The latter category can be split into the following sub-categories: epithelial–stromal tumors, sex cord–stromal tumors, germ cell tumors, and secondary tumors. It is also crucial to consider the clinical context of each individual patient diagnosed with an AM. Multimodality imaging assessment plays a key role in the management of adnexal masses and helps to plan the most appropriate therapeutic approach.