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Background:Preoperative treatment of resectable liver metastases from colorectal cancer (CRC) is a matter of debate. The aim of this study was to assess the feasibility and activity of bevacizumab plus FOLFIRI in this setting.Methods:Patients aged 18-75 years, PS 0-1, with resectable liver-confined metastases from CRC were eligible. They received bevacizumab 5 mg kg−1 followed by irinotecan 180 mg m−2, leucovorin 200 mg m−2, 5-fluorouracil 400 mg m−2 bolus and 5-fluorouracil 2400 mg m−2 46-h infusion, biweekly, for 7 cycles. Bevacizumab was stopped at cycle 6. A single-stage, single-arm phase 2 study design was applied with 1-year progression-free rate as the primary end point, and 39 patients required.Results:From October 2007 to December 2009, 39 patients were enrolled in a single institution. Objective response rate was 66.7% (95% exact CI: 49.8-80.9). Of these, 37 patients (94.9%) underwent surgery, with a R0 rate of 84.6%. Five patients had a pathological complete remission (14%). Out of 37 patients, 16 (43.2%) had at least one surgical complication (most frequently biloma). At 1 year of follow-up, 24 patients were alive and free from disease progression (61.6%, 95% CI: 44.6-76.6). Median PFS and OS were 14 (95% CI: 11-24) and 38 (95% CI: 28-NA) months, respectively.Conclusion:Preoperative treatment of patients with resectable liver metastases from CRC with bevacizumab plus FOLFIRI is feasible, but further studies are needed to define its clinical relevance. [ABSTRACT FROM AUTHOR]

Background: Venous thrombosis is a common occurrence in cancer patients, developing spontaneously or in combination with indwelling central venous devices (CVD). Purpose: To analyze the multidetector CT (MDCT) prevalence, appearance, and significance of catheter-related thoracic venous thrombosis in oncologic patients and to determine the percentage of thrombi identified in the original reports. Material and Methods: Five hundred consecutive patients were considered. Inclusion criteria were: presence of a CVD; availability of a contrast-enhanced MDCT; and cancer history. Exclusion criteria were: direct tumor compression/infiltration of the veins; poor image quality; device tip not in the scanned volume; and missing clinical data. Seventeen (3.5%) out of the final 481 patients had a diagnosis of venous thrombosis. Results: Factors showing the highest correlation with thrombosis included peripherally-inserted CVD, right brachiocephalic vein tip location, patient performance status 3, metastatic stage disease, ongoing chemotherapy, and longstanding CVD. The highest prevalence was in patients with lymphoma, lung carcinoma, melanoma, and gynecologic malignancies. Eleven out of 17 cases had not been identified in the original report. Conclusion: CVD-related thrombosis is not uncommon in cancer patients and can also be observed in outpatients with a good performance status and a non-metastatic disease. Thrombi can be very tiny. Radiologists should be aware of the possibility to identify (or overlook) small thrombi. [ABSTRACT FROM AUTHOR]

Background: Imaging is an essential tool in the management of patients with Colorectal cancer (CRC) by helping evaluate number and sites of metastases, determine resectability, assess response to treatment, detect drug toxicities and recurrences. Although multidetector computed tomography (MDCT) is the first tool used for staging and patient's surveillance, magnetic resonance imaging (MRI) is the most reliable imaging modality that allows to assess liver metastases. Our purpose is to compare the diagnostic performance of gadoxetic acid-(Gd-EOB) enhanced liver MRI and contrast-enhanced MDCT in the detection of liver metastasis from colorectal cancer (mCRC)., Methods: One hundred and twenty-eight patients with pathologically proven mCRC (512 liver metastases) underwent Gd-EOB MRI and MDCT imaging. An additional 46 patients without mCRC were included as control subjects. Three radiologists independently graded the presence of liver nodules on a five-point confidence scale. Sensitivity and specificity for the detection of metastases were calculated. Weighted к values were used to evaluate inter-reader agreement of the confidence scale regarding the presence of the lesion., Results: MRI detected 489 liver metastases and MDCT 384. In terms of per-lesion sensitivity in the detection of liver metastasis, all three readers had higher diagnostic sensitivity with Gd-EOB MRI than with MDCT (95.5% vs. 72% reader 1; 90% vs. 72% reader 2; 96% vs. 75% reader 3). Each reader showed a statistical significant difference (p < <.001 at Chi square test). MR imaging showed a higher performance than MDCT in per-patient detection sensitivity (100% vs. 74.2% [p < <.001] reader 1, 98% vs. 73% [p < <.001] reader 2, and 100% vs. 78% [p < <.001] reader 3). In the control group, MRI and MDCT showed similar per-patient specificity (100% vs. 98% [p = 0.31] reader 1, 100% vs. 100% [p = 0.92] reader 2, and 100% vs. 96% [p = 0.047] reader 3). Inter-reader agreement of lesion detection between the three radiologists was moderate to excellent (k range, 0.56-0.86) for Gd-EOB MRI and substantial to excellent for MDCT (k range, 0.75-0.8)., Conclusion: Gadoxetic acid-enhanced MRI performs significantly better in the detection of mCRC, than MDCT, particularly in patients treated with chemotherapy, in subcapsular lesions, and in peribiliary metastases.

To assess the safety profile of iso-osmolar contrast medium (CM) versus low osmolar CM in cancer patients with an estimated glomerular filtration rate (eGFR) >60 ml/min. In this multicenter, blind trial of patients seeking a chest-abdomen-pelvis contrast enhanced computed tomography (CT) with iodated CM, participants were centrally randomized to iodixanol or iopromide. Contrast induced nephropathy (CIN) at 24 and/or 72 hr were our primary outcomes. We further considered irreversible CIN, average eGFR percentage variation (%Δ), and adverse events (AEs). Overall, 607 patients were enrolled. Among them, 497 eligible patients were randomized to iodixanol (N: 247) or iopromide (N: 250). No differences emerged by descriptive characteristics. Seven and 3 CIN at 24 hr (p = 0.34) and 8 and 2 CIN at 72 hr (p = 0.11) occurred in the iopromide and iodixanol group, respectively. Within the subgroup of individual patients who developed CIN (N: 17), the event rate was higher in the iopromide arm (p = 0.045). No cases of permanent CIN or significant differences in terms of AEs or GFR %Δ were observed. Our results suggest a more favorable safety profile of iodixanol versus iopromide. Adequately sized trials with similar design are warranted to confirm our findings and clarify the underlying biological mechanisms., (© 2017 Wiley Periodicals, Inc.)

Ductal adenocarcinoma of the pancreas is one of the most aggressive forms of cancer, with only a minority of cases being resectable at the moment of their diagnosis. The accurate detection and characterization of pancreatic carcinoma is very important for patient management. Multidetector-row computed tomography (MDCT) has become the cross-sectional modality of choice in the diagnosis, staging, treatment planning, and follow-up of patients with pancreatic tumors. However, approximately 11% of ductal adenocarcinomas still remain undetected at MDCT because of the lack of attenuation gradient between the lesion and the adjacent pancreatic parenchyma. In this systematic literature review we investigate the current evolution of the CT technique, limitations, and perspectives in the evaluation of pancreatic carcinoma.

Background: Despite the improvements in diagnosis and treatment, colorectal cancer (CRC) is the second cause of cancer deaths in both sexes. Therefore, research in this field remains of great interest. The approval of bevacizumab, a humanized anti-vascular endothelial growth factor (VEGF) monoclonal antibody, in combination with a fluoropyrimidine-based chemotherapy in the treatment of metastatic CRC has changed the oncology practice in this disease. However, the efficacy of bevacizumab-based treatment, has thus far been rather modest. Efforts are ongoing to understand the better way to combine bevacizumab and chemotherapy, and to identify valid predictive biomarkers of benefit to avoid unnecessary and costly therapy to nonresponder patients. The BRANCH study in high-risk locally advanced rectal cancer patients showed that varying bevacizumab schedule may impact on the feasibility and efficacy of chemo-radiotherapy., Methods/design: OBELICS is a multicentre, open-label, randomised phase 3 trial comparing in mCRC patients two treatment arms (1:1): standard concomitant administration of bevacizumab with chemotherapy (mFOLFOX/OXXEL regimen) vs experimental sequential bevacizumab given 4 days before chemotherapy, as first or second treatment line. Primary end point is the objective response rate (ORR) measured according to RECIST criteria. A sample size of 230 patients was calculated allowing reliable assessment in all plausible first-second line case-mix conditions, with a 80% statistical power and 2-sided alpha error of 0.05. Secondary endpoints are progression free-survival (PFS), overall survival (OS), toxicity and quality of life. The evaluation of the potential predictive role of several circulating biomarkers (circulating endothelial cells and progenitors, VEGF and VEGF-R SNPs, cytokines, microRNAs, free circulating DNA) as well as the value of the early [(18)F]-Fluorodeoxyglucose positron emission tomography (FDG-PET) response, are the objectives of the traslational project., Discussion: Overall this study could optimize bevacizumab scheduling in combination with chemotherapy in mCRC patients. Moreover, correlative studies could improve the knowledge of the mechanisms by which bevacizumab enhance chemotherapy effect and could identify early predictors of response. EudraCT Number: 2011-004997-27 TRIAL REGISTRATION: ClinicalTrials.gove number, NCT01718873.

Objective: Irreversible electroporation (IRE) is a new ablation modality. Our purpose was to describe the effectiveness and the safety of the treatment and to evaluate the magnetic resonance imaging (MRI), computed tomography (CT) and contrast-enhanced ultrasound (CEUS) diagnostic accuracy in HCC patients treated with IRE at 1-, 3-, and 6-month follow-up., Materials and Methods: In an 18-month period, we treated 24 HCC lesions in 20 patients unfit for surgery. MRI, CT and CEUS were performed before and one, 3 and 6 month after IRE. We employed the liver-specific contrast medium Primovist (gadolinium ethoxybenzyl dimeglumine) in MRI. After IRE the lesions were classified as responders or non-responders to the treatment according to the mRECIST and the complications were recorded. We evaluated the size, shape, signal intensity (T1-W, T2-W, and DWI) in MRI, dynamic contrast enhancement pattern for CEUS, CT and MRI and signal behavior during the liver-specific phase for MRI., Results: According to mRECIST, at 1 month MRI and CEUS showed a complete response (CR) in 91.7% of cases (22/24) tumors, while there was partial response (PR) in the remaining 2/24 (8.3%) treated nodules; in CT study all ablated zone appeared as necrotic (CR 100%). The residual viable tumor in MRI and in CEUS study had similar diameter (10 mm). No new HCC were identified from MRI, CT or CEUS. At 3 months MRI and CEUS showed the same results seen after 1 month from the treatment. Twenty-two necrotic lesions, and 2 residual tumors were found (CR = 91.7% and PD = 8.3%). In MRI study the two cases of residual tumor tissue had a diameter of 11 and 12 mm each. At CEUS the diameter of residual HCC was similar to the diameter at 1 month. CT showed 23 necrotic areas and one residual viable tissue in the treated zone, with a diameter of 10 mm (CR = 95.3% and PD = 4.7%). No new foci of HCC were identified from all imaging studies. At 6 months MRI, CEUS, and CT showed 22 necrotic lesions and 2 residual tumors in ablated zone (CR = 91.7% and PD = 8.3%). At MRI the diameters of the two residual viable HCCs were 12 and 14 mm, at CEUS the diameters were 11 and 12 mm, while at CT the diameters were 10 and 10 mm. No statistical difference was evaluated between CR, PR, PD percentage values for MRI, CT and CEUS (p value > 0.05 at Chi-square test). No major vascular complication was recorded after IRE. Six out of 20 patients (30%) showed a transient hepatic intensity difference (THID) area within the normal liver parenchyma adjacent to the treated lesions. Two of the 20 patients (10%) showed an absent concentration of liver-specific contrast medium around the ablation zone. Two patients developed complications, consisting in a peripheral arteriovenous shunt and a segmental dilation of the intrahepatic biliary ducts. We found no statistically significant difference in morphology, size (variation in the largest diameter), signal intensity in T1-weighted images, in T2-weighted images, in DWI and in the related map of the apparent diffusion coefficient (ADC), presence or absence of contrast enhanced during the arterial, portal, and late phase in MRI, CT, and CEUS, and signal characteristic during the liver-specific phase in MRI of the ablation zone at 1, 3, and 6 months., Conclusion: IRE is a feasible, safe and efficient modality in the treatment of patients with non-resectable HCC. We had no major complication, even when the ablated lesion was adjacent to major branches of the portal vein. All images techniques showed similar accuracy during the follow-up at 1, 3, and 6 months in the assessment ablated zone.

Unlabelled: Markers predictive of treatment effect might be useful to improve the treatment of patients with metastatic solid tumors. Particularly, early changes in tumor metabolism measured by PET/CT with (18)F-FDG could predict the efficacy of treatment better than standard dimensional Response Evaluation Criteria In Solid Tumors (RECIST) response., Methods: We performed PET/CT evaluation before and after 1 cycle of treatment in patients with resectable liver metastases from colorectal cancer, within a phase 2 trial of preoperative FOLFIRI plus bevacizumab. For each lesion, the maximum standardized uptake value (SUV) and the total lesion glycolysis (TLG) were determined. On the basis of previous studies, a ≤ -50% change from baseline was used as a threshold for significant metabolic response for maximum SUV and, exploratively, for TLG. Standard RECIST response was assessed with CT after 3 mo of treatment. Pathologic response was assessed in patients undergoing resection. The association between metabolic and CT/RECIST and pathologic response was tested with the McNemar test; the ability to predict progression-free survival (PFS) and overall survival (OS) was tested with the Log-rank test and a multivariable Cox model., Results: Thirty-three patients were analyzed. After treatment, there was a notable decrease of all the parameters measured by PET/CT. Early metabolic PET/CT response (either SUV- or TLG-based) had a stronger, independent and statistically significant predictive value for PFS and OS than both CT/RECIST and pathologic response at multivariate analysis, although with different degrees of statistical significance. The predictive value of CT/RECIST response was not significant at multivariate analysis., Conclusion: PET/CT response was significantly predictive of long-term outcomes during preoperative treatment of patients with liver metastases from colorectal cancer, and its predictive ability was higher than that of CT/RECIST response after 3 mo of treatment. Such findings need to be confirmed by larger prospective trials.

Aim: Azoxymethane (AOM) is a potent carcinogen that induces colorectal cancer in mice. Intraluminal gel ultrasound is a technique based on the injection of gel into the rectum. This technique allows the colon to be straightened and to visualize and identify tumours., Materials and Methods: Twenty female C57Bl/6J mice were injected intraperitoneally with 10 mg/kg of AOM one time per week for six weeks. The mice were monitored by ultrasound with a Vevo 2100 system. We evaluated the tumour area and tumour vasculature with Ecocolor-Doppler (ECD). Histological examination of sacrificed mice was employed as the standard protocol., Results: After 40 weeks from the injection, ultrasound analysis revealed the presence of tumours in 50% of all mice. Ex vivo analysis revealed the presence of 57% true-positives and only one false-positive. In two mice, ultrasound did not reveale the presence of tumour due to its small dimension. This indicates that ultrasound is able to detect only tumours with sizes ≥3 mm²., Conclusion: Ultrasound is a rapid examination compared to other diagnostic techniques. It has a good sensitivity when the tumours reach the dimensions of 3 mm² or more. Intraluminal gel allows for the tumour area to be evaluated when mice are still alive, while ECD allows for vasculature of intestinal walls and colorectal tumour to be evaluated.

Purpose. To compare the diagnostic accuracy of hepatospecific contrast-enhanced MRI versus triple-phase CT scan after radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients. Methods. Thirty-four consecutive HCC patients (42 hepatic nodules) were treated with percutaneous RFA and underwent MR and CT scans. All patients were enrolled in a research protocol that included CT with iodized contrast medium injection and MR with hepatospecific contrast medium injection. All patients were restaged within four weeks and at 3 months from ablation. The images were reviewed by four different radiologists to evaluate tumor necrosis, residual or recurrence disease, and evidence of new foci. Results. Thirty-two nodules were necrotic after treatment; 10 showed residual disease. Six new HCCs were identified. At first month followup CT has identified 34 necrotic lesions and 8 residual diseases; no new foci were recognized. At MRI instead, 32 complete necrotic lesions were identified, 10 lesions showed residual disease, and 2 new HCCs were found. At three months, CT demonstrated 33 completely necrotic lesions, 9 residual diseases, and 2 new HCCs. MR showed 31 complete necrotic lesions, 11 cases of residual disease, and 6 new HCCs. Conclusions. Hepatospecific contrast-enhanced MRI is more effective than multiphase CT in assessment of HCC treated with RFA.

Objective: The goal of this article is to discuss and show the common complications of biliary and gastrointestinal stents as depicted by MDCT in cancer patients. Major complications include stent misplacement or displacement, bleeding, obstruction, perforation, stent fracture or collapse, and infection. This topic encompasses several relevant issues, including interpretative difficulties, therapeutic decisions, and potential malpractice concerns., Conclusion: Awareness and methodical assessment of stents could allow detection of stenting complications, potentially sparing the patient from associated morbidity and mortality.

This article is a reasoned pictorial review illustrating the many faces of thrombotic and embolic disease developing in the cancer patient. From a clinical point of view, we particularly point out the importance of properly identifying this occurrence in its various presentations. From a radiological point of view, special emphasis is given to the wide spectrum of multidetector CT findings, to the clues of benign and malignant thrombus diagnosis, and to the potential interpretative pitfalls.

Background: Aim of this study is to illustrate the multidetector row computed tomographic findings related to oesophageal injuries and their significance for therapeutic decisions., Method: From April 2002 to April 2005 we studied 16 patients with suspected oesophageal injury. Ten patients underwent standard chest radiograph, while five patients with suspected foreign body ingestion were submitted to cervical plain film and gastrografin swallow study. All 16 patients underwent multidetector row CT examination., Results: In six patients with cervical, thoracic and abdominal trauma, CT showed the presence of thoracic traumatic lesions and findings suggestive of perforation of the oesophagus. In five patients with foreign body ingestion cervical radiography was positive in only one case, while CT showed the presence of a foreign body in all cases. In three patients with post-intubation complications, CT showed the presence of perioesophageal fluid collection containing small gas bubbles in two cases and an oesophageal-aortic fistula in one case. In the remaining two patients with suspected spontaneous oesophageal perforation, CT demonstrated an oesophageal wall oedema and thickening in one case, and oesophageal fluid distension with perioesophageal small bubbles gas and fluid in the second case., Conclusion: Oesophageal injuries, when complicated with perforation, constitute a life-threatening condition. Knowledge of the CT signs of oesophageal injuries has important implications for the role of imaging at the time of initial diagnosis.

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumours of the alimentary tract. They normally involve the stomach, the small bowel, or the colon. Localisation within the oesophagus, rectum, mesentery, omentum, or retroperitoneum is less common. GISTs are immunohistochemically identified by the expression of the c-kit protein, which is not detected in other mesenchymal tumours. The role of imaging includes the detection (subjects with occult gastrointestinal bleeding, incidental recognition, etc.), characterisation, analysis of relations between mass and gastrointestinal wall, staging, prognostic assessment (recognition of signs of malignancy and unfavourable prognosis), and follow-up during specific treatment. Owing to the frequent exophytic growth of these lesions, differentiation of these tumours from nondigestive lesions of different nature is a common diagnostic problem. Imaging findings usually allow differentiation from gastrointestinal epithelial tumours but not from non-epithelial tumours, for which histological confirmation is necessary, in part to verify potential response to therapy. Smaller lesions, which are usually benign, tend to be well-defined, relatively homogeneous, and with intraluminal growth. Larger lesions normally show well-defined or ill-defined margins, inhomogeneous density both on unenhanced and on contrast-enhanced scans, with combined intraluminal/extraluminal growth and a tendency to spread to surrounding structures. Internal attenuation is often necrotic or clearly fluid. Signs of high-grade GIST include liver metastasis, gastrointestinal wall infiltration, large volume, irregular surface, ill-defined margins, inhomogeneous enhancement and peritoneal spread. Recurrences usually share the appearance of the larger, primary malignant GIST.

Purpose: To assess the role CT in the evaluation of traumatic and spontaneous oesophageal perforation., Materials and Methods: From March 2001 to May 2003, we studied 12 patients (7 males and 5 females; age range: 25-66 years, mean age: 43.5 years) with suspected oesophageal perforation due to motor-vehicle accidents (4 cases), stab wound (one case), post-intubation (2 cases), foreign body ingestion (2 cases) and spontaneous (3 cases). Five patients underwent standard chest and cervical radiography; two patients with suspected foreign body ingestion also underwent a gastrografin swallow study; all of the 12 patients underwent CT of the neck, chest and abdomen before and after intravenous, and in four cases oral, administration of contrast material., Results: In 5 patients with cervical, thoracic and abdominal trauma, the CT examination showed the presence of pleuroparenchymal injury (pneumothorax, pleural effusion and subcutaneous emphysema) as well as findings suggestive of oesophageal perforation: peri-oesophageal air (5 cases), peri-oesophageal fluid (4 cases), oesophageal wall thickening (3 cases), oesophageal wall laceration (2 cases) with abnormal course of the nasogastric tube in one of them and extraluminal extravasation of oral contrast material (2 cases). In 2 patients with post-intubation complications, CT showed the presence of a small peri-oesophageal fluid collection containing small gas bubbles in one case, and a gross perioesophageal abscess-like collection in the second case. In the 2 patients with foreign body ingestion, the plain radiography associated with CT showed the presence of a thin metal object in the cervical region (fragment of a dental plate) and a small extraluminal extravasation of gastrografin in one case, whereas in the other case CT showed the presence of a foreign body (chicken bone) in the hypopharynx with oesophageal wall thickening and peri-oesophageal oedema. In the remaining three patients with suspected spontaneous oesophageal perforation, CT showed the presence of a intramural haematoma in one case, oesophageal fluid distension with gas and a small peri-oesophageal fluid effusion (Mallory-Weiss syndrome) in another, and oesophageal rupture (Boerhaave syndrome) in the last case., Conclusions: Our experience shows that in patients with suspected traumatic and spontaneous oesophageal perforation, standard cervical and chest radiography may suggest a suspected oesophageal perforation in only a small proportion of cases, whereas oral contrast oesophagography has a higher sensitivity. Through the careful analysis of suggestive and specific signs of oesophageal perforation, a correct CT examination enables an accurate and timely diagnosis which significantly affects prognosis and provides valuable indications for treatment.

Acute pelvic pain in women is a frequent cause of emergency hospital admission. Because the source may be either gynaecological or non-gynaecologic and because of the complex anatomy of the pelvic area, the differential diagnosis of the underlying disease is extensive. In such cases ultrasonography is the procedure of choice, as it leads to a diagnosis in most cases. Sometimes, however, when the sonographic findings are non-diagnostic or disagree with the clinical picture, especially in acutely ill patients, a Computed Tomography (CT) scan of the abdomen and pelvis can assist in the diagnosis. We present the CT features of different gynaecological and non-gynaecological conditions in women presenting to the Emergency Room with acute pelvic pain.

The CT diagnosis of bowel and mesenteric injuries is difficult and warrants optimal technique and skilled interpretation. We retrospectively reviewed 36 consecutive patients with blunt traumatic injuries to the bowel and mesentery at our regional level I trauma center during the past 3 years. Physical examination, laboratory, Computed tomographic (CT), and intraoperative findings were compared. Surgically proven bowel injuries (13 cases) occurred in the duodenum (three cases), ileum (two cases), jejunum (two cases), colon (three cases), and stomach (three cases). CT findings considered specific of bowel rupture were observed in 5/13 patients including: extraluminal oral contrast or luminal content extravasation (four cases) and discontinuity of hollow viscus wall (one case). In the remaining 8/13 CT findings considered suggestive of bowel injury consisted of: pneumoperitoneum (six), gas bubbles close to the injured hollow viscus (three), thickened (>4-5mm) bowel wall (five), bowel wall hematoma (three), intraperitoneal fluid of unknown source (three). Mesenteric injury (23 cases) were surgically observed at the level of the mesenteric vessels (17 cases), legament of Treitz (two cases), gastro-duodenal artery (one case), transverse (one case) and sigmoid mesocolon (one case). CT finding considered specific of mesenteric laceration was active extravasation of contrast material from the mesenteric vessels (10 cases). CT findings suggestive of mesenteric injury (13 cases) consisted of: mesenteric hematoma (five) and/or high attenuation fluid collections, within the mesenteric root (eight) and folds (four). Helical CT is sensitive in the identification of bowel and mesenteric injury after blunt trauma providing a wide spectrum of findings. However, CT cannot be used as the sole indicator in cases with isolated thichened bowel wall, mesenteric hematoma, bowel hematoma, pneumoperitoneum or gas bubbles. Persistent, active extravasation of intravenous constrast medium from the mesenteric vessels, in isolation or associated with further injuries, requires immediate exploration and repair; disruption of bowel wall and extravasation of oral contrast are definite signs of bowel rupture. Close clinical observation, monitoring, and surgical expertise are mandatory for appropriate management.

Purpose: We investigated the role of Helical Computed Tomography (CT) as primary screening imaging modality in the diagnosis of pulmonary embolic disease., Material and Methods: We retrospectively reviewed the CT examinations, resulted positive for pulmonary embolism, performed in 134 patients (69 men and 65 women, ranging in age 23-83 years) from June 1998 to June 1999. CT was performed with a helical unit (thickness 3 mm, reconstruction interval 2 mm, pitch 1.5) after intravenous contrast agent (120 mL) rapid infusion (4 mL/s, 15s acquisition delay from bolus starting) and using a power injector. The spiral acquisition was performed from the apex of the pulmonary trunk to the diaphragm. Pulmonary embolism was considered as complete when a filling defect was present in a main pulmonary artery, as moderate when a filling defect was observed in an interlobar pulmonary artery and as very small when a filling defect was identified in a segmental pulmonary artery., Results: Helical CT allowed us to identify the presence of a filling defect in the main pulmonary artery in 60.4% of cases (complete pulmonary embolism), in an interlobar pulmonary artery in 27.6% of cases (moderate pulmonary embolism) and in a segmental pulmonary artery in 11.9% of cases (very small pulmonary embolism). At helical CT study, pulmonary embolus was identified as complete filling defect (92.5% of cases), thromboembolic mass floating freely in the lumen (28.3%) and partial filling defect (19.4%). Pleural effusion and pulmonary infarction were associated in 46.2% and 20.1% respectively., Discussion and Conclusions: Pulmonary embolic disease continues to be a major cause of morbidity and mortality. The clinical diagnosis of pulmonary embolism remains an important challenge: among the different imaging modalities, contrast-enhanced helical CT can be used as primary screening imaging modality in the diagnosis of pulmonary embolism, allowing us to detect the presence of pulmonary embolus in the main, lobar and segmental artery, as demonstrated in our experience.

Purpose: We retrospectively evaluated the radiological findings observed at plain abdominal film, abdominal sonography and abdominal CT performed in 66 patients with surgically proven small bowel volvulus., Material and Methods: Sixty-six patients (35 women and 31 men, ranging in age 38-77 years) with surgically proven small bowel volvulus were submitted to plain film, sonography and CT of the abdomen. Abdominal plain film was performed in the upright position (postero-anterior view) in 46 cases, and in the supine position in 20 cases. On plain abdominal film we evaluated the following findings: bowel loops dilatation, air-fluid levels and site of obstruction. At abdominal US, performed with 3.5 e 7.5 MHz probes, we retrospectively searched for: bowel loop dilatation, bowel wall thickening, peristalsis alteration, extraluminal fluid. CT was performed with a helical unit (thickness 4 mm, reconstruction interval 4 mm, pitch 1.5), after intravenous contrast agent (120 ml) infusion (3 ml/s, 55 s acquisition delay from bolus starting) and using a power injector. The following CT findings were searched for: whirl sign, beak sign, extraluminal fluid, bowel loop dilatation, bowel wall thickening, bowel wall or mesenteric alterations., Results: Plain abdominal film showed the following findings: air-fluid levels (92.4% of cases), bowel loops dilatation (71.2%), site of obstruction (42.4%). Abdominal sonography demonstrated bowel loop dilatation (48.5%), extraluminal fluid (48.5%), peristalsis alteration (27.3%), bowel wall thickening (27.3%). The most frequent CT findings were: bowel loop dilatation (95.5%), bowel wall thickening (78.8%), beak sign (69.7%), mesenteric alterations (66.7%), extraluminal fluid (54.5%), whirl sign (13.6%)., Conclusions: Air-fluid levels and bowel loop dilatation were the most frequent radiological findings in our series. Plain abdominal film allowed us to identify signs of obstruction, whereas signs of bowel wall necrosis were accurately shown by abdominal CT.

Purpose: We investigated the role of Helical Computed Tomography (CT) in the evaluation of low or high flow vascular injuries in patients with blunt pelvic trauma., Material and Methods: From May 1998 to December 1999, forty-nine patients (32 men and 17 women, ranging in age 14-59 years) with acute symptoms from blunt pelvic trauma were submitted to Computed Tomography (CT). A conventional radiography of the pelvis had been performed in all cases. CT was performed with a helical unit (thickness 8 mm, reconstruction interval 8 mm, pitch 1.5) after intravenous contrast agent (150-180 mL) rapid infusion (4-5 mL/s, 60 s acquisition delay from bolus starting) and using a power injector. A second spiral acquisition was performed in all cases from the iliac roofs to the inferior border of the pubic symphysis. Vascular hemorrhage was considered as low flow when the hematoma appeared as a focal homogeneous density area and as high flow when associated with contrast agent extravasation. Moreover, traumatic assessment included evaluation of the hematoma, of the leakage site and of the involved vessel., Results: Radiologic examination of the pelvis revealed fractures in 35/49 patients (71.4%). Helical CT allowed us to identify low flow hemorrhage in 37 patients, affected with hematomas from fracture of the iliac wing or of the sacrum (14 cases), tear of the pelvic (3 cases) or extrapelvic (4 cases) muscular structures, or injury of the venous plexus (20 cases). In four patients two vascular injuries were detected. High flow hemorrhage was seen in 12 patients, who had Helical CT findings of contrast agent extravasation along the common iliac vein (3 cases), external iliac artery (3 cases), internal iliac artery (4 cases), internal pudendal artery (1 case), obturator artery (1 case), inferior epigastric artery (2 cases), superior gluteal artery (2 cases), inferior gluteal artery (1 case), cremasteric artery (1 case). In 6 patients with high flow hemorrhage, two vascular injuries were shown. In all these patients, an extraperitoneal hematoma was associated with the contrast agent extravasation., Discussion and Conclusions: Fractures of the pelvic ring generally result from severe trauma. Management of these injuries must include not only treatment of the skeletal trauma but also of the associated shock and complications. Major blood loss usually occurs as a result of bleeding from the branches of the internal iliac artery. With respect to pelvic plain radiography, CT provides superior detailing of fractures, position of fracture fragments and extent of diastasis of the sacroiliac joints and pubic symphysis. Moreover CT provides diagnostic information regarding the presence or absence of pelvic bleeding and can identify the site of bleeding. In our experience, Helical CT allows us to distinguish high flow hemorrhage, where vascular injuries must be treated first, from low flow hemorrhage which can be managed differently.

The authors report on the use of US in the evaluation of osteogenesis in the fractures treated with external fixation. From April 1991 to October 1992, fifty patients with diaphyseal fractures were submitted to real-time US examinations, with 7.5-5 MHz probes, mainly on longitudinal scans. The evolutive stage of bone callus was studied and, in the presence of periosteal bone bridge, its length and height were measured. In all but 4 patients US, unlike radiology, allowed the signs of osteogenesis to be detected as early as from day 10 on and the peculiar bilobate pattern known as primary callus response was clearly demonstrated. This stage is of fundamental importance because it allows, when periosteal callus is absent, direct intervention on the dynamic process, by varying the external fixation-bone complex so as to make it more flexible. In 80% of patients periosteal apposition was observed on day 24. Delayed osteogenesis depended on the patient's age and on fracture type. Such pathologic signs as hyperstimuli, pseudoarthrosis and/or hematoma persistence were quite unfrequent findings. Even though the study of US semiology is still in progress, our results are in substantial agreement with literature data and emphasize the role of US in the early evaluation of the bone callus and its evolution.

Protein A from Staphylococcus aureus (Staph A) induces histamine secretion from human basophil leucocytes in the concentration range 10(-4) - 10 micrograms/ml. This reaction has great similarities to that of antigen or anti-IgE-induced release. It is characterized by a two stage reaction, requires extracellular calcium and is optimal at 37 degrees C. The rate of release is similar to that of IgE-mediated reactions. Histamine release induced by Staph A is inhibited by metabolic inhibitors, drugs which increase intracellular cyclic AMP levels, inhibitors of lipoxygenase pathways and a phospholipase A2 inhibitor. D2O and cytochalasin B which affect microtubules and microfilaments respectively, enhance histamine release induced by Staph A. These results suggest that Staph A-induced release is modulated by intracellular cyclic AMP, arachidonic acid metabolites, requires energy and is enhanced by the disruption of microfilaments and stabilization of microtubules.

In mechanical subocclusions, when there isn't immediate urgency, is it possible and necessary to probe radiologic examination, for a better surgical evaluation. The authors describe their own experience, achieved in about 3 years, on small bowel double contrast enema. They examined 143 patients; 16 of them were suboccluded. The security and the diagnostic reliability of used method are stressed by the authors to define lesions' morphology and localization.

Segmental ischemic disease consists of segmental infarctions and ischemic stenoses. Vasculitis (LES, polyarteritis nodosa, Schönlein-Henoch syndrome), thrombosis, arteriosclerotic changes, mechanical obstructions (adhesions, hernia, volvulus, traumas), hemorrhagic disorders are the most common causes of these intestinal lesions. The authors report their experience achieved during three years on 428 small bowel examinations; among these, 197 were double contrast enemas. Ten patients showed roentgenographic features referred to vascular diseases: 1 LES, 1 Schönlein-Henoch syndrome, 3 polyarteritis nodosa, 5 spontaneous hemorrhagic disorders or due to treatment with anticoagulants. The authors, after a review of the radiological findings, emphasize the high sensitivity and low specificity of double contrast small bowel enema. Furthermore they underline the usefulness of this method in demonstrating and monitoring intestinal pathologic changes.