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

AIM

To correlate the appearance of the retroportal fat plane at preoperative computed tomography (CT) and the pathology findings in resected adenocarcinoma of the pancreatic head (PDAC).

MATERIAL AND METHODS

Forty-eight patients with resected PDAC of the pancreatic head were included (24 men, 24 women, mean age 63 years, median BMI 24.1). All patients underwent CT <30 days before surgery. The state of the retroperitoneal resection margin and the presence of lymphatic or perineural invasion were obtained from pathology reports. CT images were reviewed independently by two radiologists for assessment of the retroportal fat plane and graded in two categories (clear/effaced). Inter-reader discrepancies were solved in consensus. Interobserver agreement was calculated and Fisher's test was used to assess the correlation between CT and pathology findings. Visceral fat areas were measured and correlated with CT findings.

RESULTS

A clear retroportal fat plane was significantly associated with a negative retroperitoneal margin at pathology with 100% specificity and PPV (p=0.0001). No association was observed between the appearance of the fat plane at CT and the presence of lymphatic or perineural invasion (p=ns). Interobserver agreement for retroportal fat plane evaluation was good (0.741). False-positive cases had a significantly lower visceral fat area than the correctly classified patients (p=0.0480).

CONCLUSIONS

A clear retroportal fat plane is significantly associated with negative retroperitoneal resection margins at pathology. The lack of visceral adipose tissue can lead to overestimation of retroportal fat plane involvement at preoperative CT.

Iodine Extravasation Quantification on Dual-Energy CT of the Brain Performed after Mechanical Thrombectomy for Acute Ischemic Stroke Can Predict Hemorrhagic Complications

BACKGROUND AND PURPOSE

Intracerebral hemorrhage represents a potentially severe complication of revascularization of acute ischemic stroke. The aim of our study was to assess the capability of iodine extravasation quantification on dual-energy CT performed immediately after mechanical thrombectomy to predict hemorrhagic complications.

MATERIALS AND METHODS

Because this was a retrospective study, the need for informed consent was waived. Eighty-five consecutive patients who underwent brain dual-energy CT immediately after mechanical thrombectomy for acute ischemic stroke between August 2013 and January 2017 were included. Two radiologists independently evaluated dual-energy CT images for the presence of parenchymal hyperdensity, iodine extravasation, and hemorrhage. Maximum iodine concentration was measured. Follow-up CT examinations performed until patient discharge were reviewed for intracerebral hemorrhage development. The correlation between dual-energy CT parameters and intracerebral hemorrhage development was analyzed by the Mann-Whitney U test and Fisher exact test. Receiver operating characteristic curves were generated for continuous variables.

RESULTS

Thirteen of 85 patients (15.3%) developed hemorrhage. On postoperative dual-energy CT, parenchymal hyperdensities and iodine extravasation were present in 100% of the patients who developed intracerebral hemorrhage and in 56.3% of the patients who did not (P = .002 for both). Signs of bleeding were present in 35.7% of the patients who developed intracerebral hemorrhage and in none of the patients who did not (P < .001). Median maximum iodine concentration was 2.63 mg/mL in the patients who developed intracerebral hemorrhage and 1.4 mg/mL in the patients who did not (P < .001). Maximum iodine concentration showed an area under the curve of 0.89 for identifying patients developing intracerebral hemorrhage.

CONCLUSIONS

The presence of parenchymal hyperdensity with a maximum iodine concentration of >1.35 mg/mL may identify patients developing intracerebral hemorrhage with 100% sensitivity and 67.6% specificity.

Ricostruzione tridimensionale dei vasi del collo

L'obiettivo di questo lavoro è stato quello di valutare l'efficacia della Angiografia tridimensionale TC (3D-TCA) in pazienti con patologia a carico del distretto carotideo extracranico. Sono stati esaminati 15 pazienti con stenosi di natura arteriosclerotica (14 casi) o arteritica (1 caso) a livello della biforcazione carotidea. Tutti i casi erano stati precedentemente indagati con arteriografia che è stata considerata il test di confronto. Le immagini tridimensionali, presentano una qualità molto valida e sono paragonabili a quelle angiografiche nella maggioranza dei casi. La tecnica 3D-TCA presenta a suo favore alcuni vantaggi: scarsa invasività; semplicità e rapidità di esecuzione; buona dimostrazione delle placche calcifiche che possono essere rimosse mediante software. I limiti attuali sono rappresentati da: necessità di una adeguata concentrazione di mezzo di contrasto nei vasi: possibili artefatti da calcificazioni e strutture ossee: mancanza di informazioni sul flusso dei vasi; difficile separazione tra arterie e vene in alcuni distretti; scarsa panoramicità rispetto alla angiografia.

Malignant focal liver lesions at contrast-enhanced ultrasonography and magnetic resonance with hepatospecific contrast agent

The aim of this study was to compare the diagnostic accuracy of the late phase of CEUS and the hepatobiliary phase of CE-MR with Gd-BOPTA in the characterization of focal liver lesions in terms of benignity and malignancy. A total of 147 solid focal liver lesions (38 focal nodular hyperplasias, 1 area of focal steatosis, 3 regenerative nodules, 8 adenomas, 11 cholangiocarcinomas, 36 hepatocellular carcinomas and 49 metastases) were retrospectively evaluated in a multicentre study, both with CEUS, using sulphur hexafluoride microbubbles (SonoVue, Bracco, Milan, Italy) and CE-MR, performed with Gd-BOPTA (Multihance, Bracco, Milan, Italy). All lesions thought to be malignant were cytohistologically proven, while all lesions thought to be benign were followed up. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and accuracy were calculated for the late phase of CEUS and the hepatobiliary phase of CE-MRI, respectively, and in combination. Analysis of data revealed 42 benign and 105 malignant focal liver lesions. We postulated that all hypoechoic/hypointense lesions on the two phases were malignant. The diagnostic errors were 13/147 (8.8%) by CEUS and 12/147 (8.2%) by CE-MR. Sensitivity, specificity, PPV, NPV and accuracy of the late phase of CEUS were 90%, 93%, 97%, 80% and 91%, 93%, 97%, 81% and 92% for the hepatobiliary phase of CE-MRI, respectively. If we considered both techniques, the misdiagnosis diminished to 3/147 (2%) and sensitivity, specificity, PPV, NPV and accuracy were 98%, 98%, 99%, 95% and 98%. The combination of the late phase of CEUS and the hepatobiliary phase of CE-MR in the characterization of solid focal liver lesions in terms of benignity and malignancy is more accurate than the two techniques used separately.

Comparison between CT and CEUS in the diagnosis of pancreatic adenocarcinoma

PURPOSE

The aim of this study is to compare CEUS and MDCT features of pancreatic ductal adenocarcinoma in relation to tumor size.

MATERIALS AND METHODS

All patients with pathological diagnosis of pancreatic adenocarcinoma and studied by means of CEUS and MDCT were enrolled in this study. Two radiologists evaluated tumor size, site and imaging appearance. Patients in which at least one method yielded a positive result were divided into 4 groups on the basis of lesion size. For each dimensional category, sensitivity of the two imaging methods was calculated and compared using McNemar test.

RESULTS

One hundred thirty-three patients were included in this study. In 9 of 133 patients neither MDCT nor US/CEUS could identify the lesion, while in 9 of 133 patients only MDCT and in 13 of 133 only US/CEUS could identify the lesion. In the remaining 102 patients, both MDCT and US/CEUS yielded a positive result. US/CEUS sensitivity was 86.47% while MDCT sensitivity was 83.58%, with no statistically significant difference (p = 0.523). For lesions smaller than 2 cm US/CEUS had a 100% sensitivity, while MDCT had a 73.33% sensitivity with no statistically significant difference (p = 0.125). For lesions between 2.1 and 3 cm US/CEUS had a sensitivity of 95.35%, while MDCT had a sensitivity of 83.72% with no statistically significant difference (p = 0.180). For lesions between 3.1 and 4 cm, US/CEUS had a sensitivity of 87.88%, while MDCT had a sensitivity of 93.94% with no statistically significant difference (p = 0.688). For lesions larger than 4 cm US/CEUS, had a sensitivity of 90.91%, while MDCT had a sensitivity of 100% with no statistically significant difference (p = 0.250).

CONCLUSION

US/CEUS sensitivity in diagnosing pancreatic ductal adenocarcinoma is adequate and does not statistically differ from that of MDCT. US/CEUS sensitivity seems to be higher for small and medium lesions, while MDCT sensitivity is higher for large lesions. By combining both the imaging methods a higher accuracy in diagnosing pancreatic ductal adenocarcinoma can be expected.

Perfusion CT can predict tumoral grading of pancreatic adenocarcinoma

OBJECTIVES

To describe perfusion CT features of locally advanced pancreatic ductal adenocarcinoma and to evaluate correlation with tumor grading.

METHODS

Thirty-two patients with locally advanced pancreatic adenocarcinoma were included in this study. Lesions were evaluated by P-CT and biopsy after patient's informed consent. P-CT parameters have been assessed on a large single and on 6 small intratumoral ROIs. Values obtained have been compared and related to the tumor grading using Mann-Whitney U test. Sensibility, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy in predicting tumor grading have been calculated for cut-off values chosen by using ROC curves.

RESULTS

Out of 32 lesions, 12 were classified as low grade and 20 as high grade. A statistically significant difference between high and low grade neoplasms were demonstrated for PEI and BV parameters. PEI and BV cut-off values were respectively 17.8 HU and 14.8 ml/100g. PEI identified high grade neoplasms with a 65% sensitivity, 92% specificity, 93% PPV, 61% NPV and 75% accuracy. BV identified high grade neoplasms with a 80% sensitivity, 75% specificity, 84% PPV, 69% NPV, 78% accuracy. Considering both PEI and BV, P-CT identified high grade lesions with a 60% sensitivity, 100% specificity, 100% PPV, 60% NPV and 75% accuracy.

CONCLUSIONS

PEI and BV perfusion CT parameters proved their efficiency in identifying high grade pancreatic adenocarcinoma.

Bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography and gene-mutation-associated pancreatitis (GMAP)

PURPOSE

This study prospectively assessed whether the presence of a bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography (MDCT) correlated with gene-mutation-associated pancreatitis (GMAP) and whether other signs suggestive of GMAP can be detected with MDCT.

MATERIALS AND METHODS

Forty-seven patients with chronic calcific pancreatitis underwent genetic testing for CFTR, SPINK1 and PRSS1 mutations and an MDCT scan of the abdomen. Qualitative analysis assessed the presence or absence of pancreatic-duct stones with bull's-eye appearance. Quantitative analysis included the number and maximum diameter of stones and the diameter of the main pancreatic duct.

RESULTS

Fifteen of 47 patients (32%) were positive for gene mutations (GMAP patients). The bull's-eye pattern was found in 10/15 patients (67%) with GMAP and in 4/32 (12%) patients with chronic pancreatitis not associated with GMAP (NGMAP; p<0.0001). The mean diameter of duct stones was 15 mm in patients with GMAP and 10 mm in patients with NGMAP (p<0.04).

CONCLUSIONS

The presence of duct stones with a bull's-eye pattern correlates with GMAP. Duct stones with diameter ≥15 mm are another sign suggestive of GMAP.

Pancreatic fat accumulation and its relationship with liver fat content and other fat depots in obese individuals

BACKGROUNDS AND AIMS

We assessed the associations between pancreatic fat accumulation and other fat compartments, including liver fat and visceral adipose tissue as well as insulin resistance and other metabolic abnormalities in obese individuals.

SUBJECTS AND METHODS

We studied 42 Caucasian adults with obesity [20 men and 22 women; mean body mass index (BMI) 35.2±4 kg/m(2)], who had no history of liver diseases or excessive alcohol consumption, in which subcutaneous, visceral, liver, and pancreatic fat contents were quantified by an in-opposed-phase magnetic resonance imaging (MRI) technique.

RESULTS

Compared with patients in the lower tertile (<5.6%, no.=15), those in the upper tertile of liver fat content had more visceral adipose tissue, greater insulin resistance and had higher values of BMI, blood pressure, triglycerides and lower HDL-cholesterol and adiponectin. Notably, pancreatic fat accumulation also significantly increased across tertiles of liver fat content. In univariate analysis, the strongest correlates of pancreatic fat were visceral and liver fat contents (r=0.80 and r=0.54, p<0.001- 0.0001, respectively). Pancreatic fat accumulation was also moderately associated with insulin resistance and other metabolic syndrome features. However, when adjusted for age, gender and visceral adipose tissue, the associations of pancreatic fat accumulation with liver fat and other metabolic abnormalities were no longer significant.

CONCLUSIONS

There are significant associations between pancreatic fat accumulation and liver fat content as well as insulin resistance and other metabolic abnormalities in obese, but otherwise healthy, individuals. However, these associations are largely mediated by the amount of visceral adipose tissue.

E-learning in radiology: an Italian multicentre experience

OBJECTIVE

The aim of this study was to design, deliver and evaluate an e-learning teaching programme for post-graduate radiodiagnostics training that would involve various post-graduate schools throughout Italy.

MATERIALS AND METHODS

All of the Directors of Italian post-graduate schools of radiodiagnostics were sent an e-mail on 27 September 2010 informing them of our willingness to set up an e-learning project for the academic year 2010-2011 in the form of single-subject teaching seminars. The proposed subjects were the semeiotics of the various organs and apparatuses in the context of "Urgent/Emergency Pathology". After having received registrations, a calendar of lessons was planned to be held between 10 November 2010 and 12 October 2011. The validity of the project was tested by means of a multiple-choice questionnaire covering the technical and didactic quality of the entire project, to be completed by the students.

RESULTS

Fifty-one percent of the universities in Italy participated in the project: Trieste, Udine, Verona, Milan-Bicocca, Novara, Varese, Genoa, Sassari, Rome Campus, the Catholic University of Rome, Chieti, Foggia, Catania, Modena, Florence, Palermo, Bologna, Pavia, Parma and Ferrara. The lessons were attended by a total of 10,261 post-graduate medical students, for an average of 513.1 students per lesson. Seventy percent of the students judged the didactic content "excellent", 25% "good", and 5% "satisfactory"; none said it was unsatisfactory. In terms of visual quality (particularly the details of the radiological images proposed in the form of slides and/or video clips), 73% judged it "excellent", 20% "good", 6% "satisfactory", and 1% "poor". The audio quality was judged "excellent" by 71%, "good" by 22%, "satisfactory" by 6% and "poor" by 1%. In relation to judgement of audio and video quality, it has to be underlined that this was greatly affected by the hardware/software configuration and the band speed and technology of the Internet connection.

CONCLUSIONS

Technological evolution is overcoming all barriers, and technology is also having a positive impact on the approach to teaching. Our multicentre teaching experience merits the following considerations: the quality of the teaching product was certified by the students' judgements of its didactic content and the quality of reception; the economic cost of the teaching had a minimal impact on the post-graduate schools (€ 18 per lesson). In terms of breaking down national barriers, it is to be hoped that the coordination and integration of diagnostic imaging e-learning projects, with the participation of post-graduate schools in different European countries, can be developed not only in a spirit of "cultural sharing" and the exchange of teaching experiences.

Role of coronary angiography MDCT in the clinical setting: changes in diagnostic workup in the real world

PURPOSE

The authors sought to evaluate the incremental value of introducing coronary angiography with multidetector computed tomography (MDCT-CA) compared with the conventional diagnostic workup in managing patients with suspected coronary artery disease (CAD) workup.

MATERIALS AND METHODS

A total of 531 consecutive patients underwent MDCT-CA between April 2008 and August 2010. For each patient the pretest probability of CAD was obtained by using the Morise score as well as the diagnostic performance of the exercise test and of MDCT-CA, considering conventional coronary angiography (CCA) as the gold standard. Based on these results, we calculated the posttest likelihood of CAD after stress testing, comparing the incremental diagnostic value for each category of cardiovascular risk with data obtained with MDCT-CA. The conventional diagnostic workup (without MDCT-CA) was then compared with the modified workup (including MDCT-CA).

RESULTS

The diagnostic performance of the exercise test for identifying patients with significant lesions had a sensitivity and specificity of 20% and 88%, respectively, with positive (PPV) and negative (NPV) predictive value of 41% and 72%, respectively. Taking CA as the gold standard, MDCT-CA had 93% sensitivity, 89% specificity, 88% PPV and 93% NPV compared with CCA in evaluating significant stenoses in the per-patient analysis. The overall diagnostic accuracy of MDCT-CA was 91%. The exercise tests provided no significant incremental diagnostic value compared with cardiovascular history in patients with a low to intermediate risk. Comparison of the diagnostic accuracy of these protocols showed improved performance results for the modified protocol.

CONCLUSIONS

MDCT-CA is the reference modality for the noninvasive exclusion of critical CAD. It provides a very high incremental diagnostic value compared with exercise testing in patients with a low to intermediate risk of CAD. The use of diagnostic protocols based on MDCT-CA ensures improved diagnostic performance compared with those involving conventional exercise electrocardiograms.

Effect of moderate weight loss on hepatic, pancreatic and visceral lipids in obese subjects

OBJECTIVE

To compare the effects of weight loss on visceral and subcutaneous abdominal fat, liver and pancreas lipid content and to test the effects of these changes on metabolic improvement observed after weight loss.

DESIGN

Weight-loss program designed to achieve a loss of 7-10% of the initial weight.

SUBJECTS

24 obese subjects (13 males and 11 females) with age ranging from 26 to 69 years and body mass index (BMI) 30.2-50.5 kg m(-2).

MEASUREMENTS

weight, BMI, waist circumference, body composition as assessed by dual-energy X-ray absorptiometry, metabolic variables, leptin, adiponectin, visceral and subcutaneous abdominal fat, liver and pancreas lipid content as assessed by magnetic resonance were evaluated before and after weight loss achieved by hypocaloric diet.

RESULTS

After a mean body weight decrease of 8.9%, BMI, waist circumference, fat mass, all metabolic variables, homeostasis model assessment of insulin resistance (HOMA), alanine amino transferase, gamma glutamyl transpeptidase, high-sensitivity C-reactive protein (hs-CRP) and leptin, but not adiponectin and high-density lipoprotein-cholesterol, significantly decreased (all P<0.01). Visceral and subcutaneos abdominal fat, liver and pancreas lipid content significantly decreased (all P<0.01). Percent changes in liver lipid content were greater (84.1±3%) than those in lipid pancreas content (42.3±29%) and visceral abdominal fat (31.9±15.6%). After weight loss, percentage of subjects with liver steatosis decreased from 75 to 12.5%. Insulin resistance improvement was predicted by changes in liver lipid content independently of changes in visceral fat, pancreas lipid content, systemic inflammation, leptin and gender.

CONCLUSION

Moderate weight loss determines significant decline in visceral abdominal fat, lipid content in liver and pancreas. Reduction of liver lipid content was greater than that of pancreas lipid content and visceral fat loss. Liver lipid content is the strongest predictor of insulin resistance improvement after weight loss.

Acoustic Radiation Force Impulse (ARFI) ultrasound imaging of solid focal liver lesions

OBJECTIVE

The aim of this paper was to evaluate the application of ARFI ultrasound imaging and its potential value for characterizing focal solid liver lesions.

MATERIALS AND METHODS

In this multicentric prospective study, over a total non-consecutive period of four months, all patients underwent ARFI US examination. Two independent operators performed 5 measurements per each lesion and 2 measurements in the surrounding liver. According to the definitive diagnosis, a mean velocity value and standard deviations were obtained in each type of focal solid lesion, compared by using t-test, and the inter-operator evaluation was performed by using the Student's t-test. A comparison between the total mean values of each type of lesion and the mean value of the parenchyma was performed.

RESULTS

40 lesions were evaluated and a total of 400 measurements were obtained. The lesions were: 6/40(15%) hepatocellular carcinomas, 7/40(17.5%) hemangiomas, 5/40(12.5%) adenomas, 9/40(22.5%) metastases and 13/40(32.5%) focal nodular hyperplasias. The total mean values obtained were: 2.17 m/s in HCCs, 2.30 m/s in hemangiomas, 1.25 m/s in adenomas, 2.87 m/s in metastases and 2.75 m/s in FNHs. The inter-operator evaluation resulted non-statistically different (p>0.05). A significant difference (p<0.05) was always found by comparing adenomas to the other lesions. 160 measurements were obtained in the surrounding parenchyma, with a no significant difference between values measured in adenomas and in the surrounding liver.

CONCLUSIONS

ARFI technology with Virtual Touch tissue quantification could non-invasively provide significant complementary information regarding the tissue stiffness, useful for the differential diagnosis of focal solid liver lesions.

Quantitative MRCP assessment of pancreatic exocrine reserve and its correlation with faecal elastase-1 in patients with chronic pancreatitis

PURPOSE

This retrospective study was done to correlate a quantitative assessment of the pancreatic exocrine reserve by dynamic secretin magnetic resonance cholangiopancreatography (MRCPQ) with the faecal elastase-1 (FE-1) test in patients with chronic pancreatitis.

MATERIALS AND METHODS

Thirty-five patients with a clinical diagnosis of chronic (CP) or acute recurrent (ARP) pancreatitis were enrolled. FE-1 was indicative of the pancreatic exocrine reserve. Subsequently, the patient population was subdivided into two groups according to a clinical threshold value of 200 μg/g. All patients underwent MRCP examination during secretin administration. Duodenal filling volume was calculated on T2-weigthed rapid acquisition with relaxation enhancement (RARE) MRCP images obtained 10 min after secretin injection. Duodenal filling volumes were compared with FE-1 values. Scatter plots, Pearson correlation coefficient and the Mann-Whitney U test were performed.

RESULTS

Thirty-five paired MRCPQ-FE1 data sets were analysed. MRCPQ was significantly different (p=0.007) between patients with impaired and preserved pancreatic function; median and interquartile range (IQR) were 150.7 ml (137.3-205.5 ml; n=9) and 332.4 ml (190.6-506.9 ml; n=26). Both Pearson correlation coefficient (p<0.001) and the Mann-Whitney U test (p=0.007) were significant.

CONCLUSIONS

MRCPQ significantly correlates with FE-1 values. It is possible to discriminate impaired and preserved pancreatic exocrine function using MRCPQ.

Comparison between different kernel reformatting filters in 3D quantitative analysis of MDCT coronary angiography

PURPOSE

Coronary angiography with multidetector-row computed tomography (MDCT-CA) allows quantification of coronary artery stenosis with a high level of accuracy; however, a better estimation of stenosis can be achieved by using appropriate reformatting filters, especially in stents and calcified segments. Quantitative computed tomography angiography (QCTA) is intended to overcome the limitations of the visual score. The aim of this study was to evaluate the accuracy of QCTA with different filters in comparison with quantitative coronary angiography (QCA) and visual score.

MATERIALS AND METHODS

Two blinded operators visually scored 17 consecutive patients referred for MDCT-CA with a per-segment analysis. The degree of stenosis was classified as 0-20%, 20-50% (wall irregularities), 50-70% (significant disease) and 70-100% (vessel occlusion). Each segment was then analysed using the electronic callipers of the QCTA system with 15 different filters. No contour editing was performed. Data were compared with QCA and conventional coronary angiography (CCA). Comparison between QCTA, visual score and QCA were performed using Spearman's rank correlation.

RESULTS

Of 25 segments analysed (mean 1.4 diseased segment per patient), 375 measurements were considered. Good correlation was found between the visual score and QCA [Pearson correlation coefficient (rho=0.852; p<0.0001)] and between QCA and CCA (rho=0.804; p<0.0001). Moderate correlation was found between QCA and QCTA only using two filters (rho=0.444; p<0.0001 for YA filter and rho=0.450; p<0.0001 for YB filter).

CONCLUSIONS

Overall QCTA accuracy is low if contour editing is not applied, especially in calcified vessels. Certain filters can help to better estimate the exact percentage of stenosis.

The diagnostic contribution of CT volumetric rendering techniques in routine practice

Computed tomography (CT) volumetric rendering techniques such as maximum intensity projection (MIP), minimum intensity projection (MinIP), shaded surface display (SSD), volume rendering (VR), and virtual endoscopy (VE) provide added diagnostic capabilities. The diagnostic value of such reconstruction techniques is well documented in literature. These techniques permit the exploration of fine anatomical detail that would be difficult to evaluate using axial reconstructions alone. Although these techniques are now widely available, many radiologists are either unfamiliar with them or do not fully utilize their potential in daily clinical practice. This paper is intended to provide an overview of the most common CT volumetric rendering techniques and their practical use in everyday diagnostics.

Multifocal, multicentric and contralateral breast cancers: breast MR imaging in the preoperative evaluation of patients with newly diagnosed breast cancer

PURPOSE

This study was done to verify the usefulness of preoperative breast magnetic resonance (MR) imaging in patients with newly diagnosed breast cancer.

MATERIALS AND METHODS

A retrospective analysis of 291 patients with invasive breast cancer newly diagnosed with conventional breast imaging (mammography and ultrasound) was performed. All patients underwent MR imaging prior to surgery. The MR imaging detection rate of additional malignant cancers occult to mammography and ultrasound was calculated. Data were analysed with Fisher's exact test (p<0.05) according to the following parameters: histopathological features of the index tumour (histological type and size) and mammographic density [according to the Breast Imaging Reporting and Data System (BI-RADS) classification from 1 fatty to 4 dense). The gold standard was the histological examination on the surgical specimen.

RESULTS

MR imaging identified 40 mammographically and sonographically occult malignant lesions other than the index cancer in 27/291 patients (9%). These additional cancers were located in the same quadrant as the index cancer in 13 women (4%), in a different quadrant in 12 (4%) and in the contralateral breast in the remaining two (1%). The cancer detection rate in the subgroup of index cancers with lobular histological type was 25%, significantly higher (p=0.03) than the detection rate of 11% recorded in the subgroup of ductal cancers. The cancer detection rate in the subgroup of index cancers >2 cm was 27%, significantly higher (p=0.001) than the rate of 8% found in the subgroup of index cancers <2 cm. Mammographic density was not correlated (p=0.48) with MR detection of additional cancer, with 14% of additional malignancies being detected in both dense and fatty breasts.

CONCLUSIONS

In patients with newly diagnosed invasive breast cancer, preoperative MR imaging is useful for detecting additional synchronous malignancies that are not detected on conventional breast imaging. The cancer detection rate is 9%. The use of preoperative MR imaging as an adjunct to conventional breast imaging in women with an infiltrating lobular index cancer and an index cancer >2 cm is especially beneficial.

Altered microstructure integrity of the amygdala in schizophrenia: a bimodal MRI and DWI study

BACKGROUND

The amygdala plays a central role in the fronto-limbic network involved in the processing of emotions. Structural and functional abnormalities of the amygdala have recently been found in schizophrenia, although there are still contradictory results about its reduced or preserved volumes.

METHOD

In order to address these contradictory findings and to further elucidate the possibly underlying pathophysiological process of the amygdala, we employed structural magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI), exploring amygdalar volume and microstructural changes in 69 patients with schizophrenia and 72 matched healthy subjects, relating these indices to psychopathological measures.

RESULTS

Measuring water diffusivity, the apparent diffusion coefficients (ADCs) for the right amygdala were found to be significantly greater in patients with schizophrenia compared with healthy controls, with a trend for abnormally reduced volumes. Also, significant correlations between mood symptoms and amygdalar volumes were found in schizophrenia.

CONCLUSIONS

We therefore provide evidence that schizophrenia is associated with disrupted tissue organization of the right amygdala, despite partially preserved size, which may ultimately lead to abnormal emotional processing in schizophrenia. This result confirms the major role of the amygdala in the pathophysiology of schizophrenia and is discussed with respect to amygdalar structural and functional abnormalities found in patients suffering from this illness.

Staging cancer of the pancreas

Pancreatic carcinoma is the fourth cause of death from cancer in the United States, with a survival rate at 5 years of less than 5%. About 60% of tumors originate at the head of the pancreas, 15% in the body, 5% in the tail; 20% are diffuse within the pancreas. This article discusses the imaging and staging of pancreatic cancer.

Evaluation of a method of computer-aided detection (CAD) of pulmonary nodules with computed tomography

PURPOSE

The authors sought to compare the sensitivity and reading time obtained using computer-aided detection (CAD) software as second reader (SR) or concurrent reader (CR) in the identification of pulmonary nodules.

MATERIALS AND METHODS

Unenhanced CT scans of 100 consecutive cancer patients were retrospectively reviewed by four readers to identify all solid, noncalcified pulmonary nodules ranging from 3 to 30 mm in diameter. The sensitivity and reading time of each reader and of CAD alone were calculated at 3-mm and 5-mm thresholds with respect to the reference standard, consisting of a consensus reading by the four radiologists involved in the study. The McNemar test was used to compare the sensitivities obtained by reading without CAD (readers 1 and 2), with CAD as SR (readers 1 and 2 with a 2-month delay), and with CAD as CR (readers 3 and 4). The paired Student's t test was used to compare reading times. A value of p<0.05 was considered statistically significant.

RESULTS

A total of 258 and 224 nodules were identified at 3-mm and 5-mm thresholds, respectively. The sensitivity of CAD alone was 62.79% and 67.41% at the 3-mm and 5-mm threshold values respectively, with 4.15 and 2.96 false-positive findings per examination. CAD as SR produced a significant increase in sensitivity (p<0.001) in nodule detection with respect to reading without CAD both at 3 mm (12.01%) and 5 mm (10.04%); the average increase in sensitivity obtained when comparing CAD as SR to CAD as CR was statistically significant (p<0.025) both at the 3-mm (5.35%) and 5-mm (4.68%) thresholds. CAD as CR produced a nonsignificant increase in sensitivity compared with reading without CAD (p>0.05). Mean reading time using CAD as SR (330 s) was significantly longer than reading without CAD (135 s, p<0.001) and reading with CAD as CR (195 s, p<0.025).

CONCLUSIONS

The use of CAD as CR, without any significant increase in reading time, produces no significant increase in sensitivity in pulmonary nodule detection when compared with reading without CAD (p>0.05); CAD as SR, at the cost of longer reading times, increases sensitivity when compared with reading without CAD (p<0.001) or with CAD as CR (p<0.025).

Imaging of neuroendocrine gastroenteropancreatic tumours

The role of imaging in functioning endocrine tumours (FETs) is primarily to detect the tumour, that is, to verify lesion number and location. Radiological detection of carcinoid tumours is limited by typical tumour location throughout the gastrointestinal tract or appendix and is therefore dependent on the tumour being large enough to make it recognisable in that site. The most common FET is insulinoma, which is commonly characterised by the typical appearance of a hypervascular lesion at multidetector-row computed tomography and magnetic resonance imaging. A particularly important role is played by intraoperative ultrasound in defining the exact number of lesions, their relationship with adjacent vascular structures and the pancreatic duct for the purposes of correct surgical planning (enucleation or resection). In the setting of nonfunctioning endocrine tumours (NFETs), which manifest late as large masses causing compression symptoms or as incidental findings, imaging is not primarily aimed at tumour detection, as this is relatively easy given the large size of the lesions. Rather, its role is to characterise the tumour and, in particular, to differentiate pancreatic NFET from ductal adenocarcinoma, as in comparison, malignant NFETs have a more favourable prognosis (5-year survival rate 40% compared with 3%-5% for adenocarcinoma) and therefore require different treatment approaches. As NFET are often malignant, they also require accurate staging and appropriate follow-up. In 80% of cases, NFETs have a "typical" imaging appearance: location in the pancreatic head, large dimensions (diameter between 5 and 15 cm, >10 cm in 30% of cases), capsule, sharp and regular margins owing to the expansile and noninfiltrative growth pattern, solid density and arterial hypervascularity. Some 20% of NFETs display different imaging characteristics ("atypical" appearance) as a result of arterial hypovascularity due to the presence of abundant fibrous stroma. Lastly, a small percentage of NFETs has yet a different appearance ("unusual") due to the cystic nature and/or diffuse location throughout the pancreatic parenchyma.

Anatomical variants and anomalies of the coronary tree studied with MDCT coronary angiography

Anomalies of the coronary arteries are congenital and in most of the cases asymptomatic, although they may present with severe symptoms such as angina pectoris or cardiac arrest. Multidetector CT coronary angiography (MDCT-CA) permits, through curved multiplanar reconstructions and three-dimensional reformatting, noninvasive visualisation of the coronary tree and its variants and anomalies, providing a more accurate alternative to conventional coronary angiography (CCA). The purpose of this pictorial essay is to describe the main variants and anomalies of the coronary arteries using MDCT imaging with multiplanar and three-dimensional reconstructions.

Resectable pancreatic adenocarcinoma: is the enhancement pattern at contrast-enhanced ultrasonography a pre-operative prognostic factor?

The aim of our study was to determine whether the enhancement pattern of pancreatic adenocarcinoma at contrast-enhanced ultrasonography (CEUS) is related to patient prognosis after resection. CEUS of 42 resected adenocarcinomas were retrospectively reviewed. Tumors were divided into two groups: group A=poorly vascularized (presence of avascular areas) or group B=well vascularized (absence of avascular areas). All lesions were resected and underwent pathological examination assessing tumor differentiation as: undifferentiated (poorly differentiated) or differentiated (moderately and well differentiated). Mean vascular density (MVD) was also evaluated. CEUS enhancement and pathology were correlated (Spearman's test). Survival was analyzed with the Kaplan-Meier method. Multivariate analysis was performed with the Cox regression model. There were 30 differentiated and 12 undifferentiated adenocarcinomas at pathology. At CEUS, 10 lesions were poorly vascularized, whereas 32 lesions were well vascularized. Positive correlation was observed between CEUS groups and tumoral differentiation (rs=0.51; p=0.001) and between CEUS and MVD (rs=0.74; p<0.0001). Median survival in patients with group A vascularization at CEUS was significantly lower than in group B (p=0.015). Cox proportional hazard model revealed the presence of poorly vascularized tumor at CEUS (p=0.0001) as a predictor of higher mortality. In conclusion, CEUS enables accurate depiction of the vascularization of adenocarcinoma, with positive correlation to histology grade and MVD.

Autoimmune pancreatitis: imaging findings on contrast-enhanced MR, MRCP and dynamic secretin-enhanced MRCP

PURPOSE

This study retrospectively determined magnetic resonance (MR), MR cholangiopancreatography (MRCP) and secretin-MRCP findings in patients with autoimmune pancreatitis (AIP).

MATERIALS AND METHODS

The MR examinations of 28 patients with histopathologically proven AIP were reviewed. In 14 cases, secretin-enhanced MRCP was performed. The observers evaluated pancreatic parenchymal enlargement, signal intensity abnormalities, enhancement, vascular involvement, bile-duct diameter and main pancreatic duct (MPD) narrowing (diffuse/focal/segmental). After secretin administration, the presence of the "duct-penetrating" sign was evaluated.

RESULTS

MR imaging showed diffuse pancreatic enlargement in 8/28(29%) cases, focal pancreatic enlargement in 16/28 (57%) cases and no enlargement in 4/28 (14%) cases. The alteration of pancreatic signal intensity was diffuse in 8/28 (29%) cases (eight diffuse AIP) and focal in 20/28 (71%) cases (20 focal AIP). Delayed pancreatic enhancement was present in all AIP, with peripheral rim of enhancement in 8/28 (29%) AIP (1/8 diffuse, 7/20 focal); vascular encasement was present in 7/28 (25%) AIP (1/8 diffuse, 6/20 focal); distal common bile duct narrowing was present in 12/28(43%) AIP (5/8 diffuse, 7/20 focal). MRCP showed MPD narrowing in 17/28 (61%) AIP (4/8 diffuse, 15/20 focal), MPD dilation in 8/28(29%) AIP (3/8 diffuse, 5/20 focal) and normal MPD in 1/8 diffuse AIP. Secretin-MRCP showed the duct-penetrating sign in 6/14(43%) AIP (one diffuse AIP with MPD segmental narrowing, five focal AIP with MPD focal narrowing), demonstrating integrity of the MPD.

CONCLUSIONS

Delayed enhancement and MPD stenosis are suggestive for AIP on MR and MRCP imaging. Secretin-enhanced MRCP is a problem-solving tool in the differential diagnosis between focal AIP and ductal adenocarcinoma.

Is intraoperative ultrasound (IOUS) still useful for the detection of liver metastases?

PURPOSE

To evaluate the clinical impact of intraoperative ultrasound (IOUS) in the detection of liver metastases during the years, as compared with those of other imaging modalities.

MATERIALS AND METHODS

All IOUS scans performed for detection of liver metastases from 2000 to 2006 were retrospectively reviewed and compared with the results of preoperative imaging modalities: Ultrasound (US), Computed Tomography (CT), and/or Magnetic Resonance (MR). The number of cases in which IOUS and preoperative imaging studies produced discordant results, in terms of presence/absence of focal liver lesions, was calculated per year. Statistical analysis was performed using the McNemar test. A p value < 0.05 was considered statistically significant.

RESULTS

Eighty-three IOUS scans performed in 2000-2003 were reviewed, and discordance with preoperative imaging findings was found in 19/83 (23%) cases. Of the 42 IOUS scans done during the 2004-2006 period, 10/42 (24%) showed discordance with preoperative studies. All metastases diagnosed with imaging studies were pathologically confirmed. The number of discordant cases in the two periods were not significantly different (p = 0.2).

CONCLUSION

IOUS is still useful in the detection of liver metastases. Its decreased use is probably due to the improved accuracy of preoperative imaging modalities.

Contrast-enhanced ultrasonography (CEUS) immediately after percutaneous ablation of hepatocellular carcinoma

PURPOSE

This study evaluated the effectiveness of contrast-enhanced ultrasound (CEUS), performed immediately after percutaneous ethanol injection (PEI) or radiofrequency thermal ablation (RFTA), by comparing results with the computed tomography (CT) follow-up.

MATERIALS AND METHODS

Sixty-nine consecutive patients with a diagnosis of hepatocellular carcinoma (HCC) were included in this prospective study. All patients underwent PEI or RFTA. After treatment, three CEUS enhancement patterns were observed: isovascular, hypovascular and avascular, which were compared with the CT findings. Sensitivity of the avascular pattern at CEUS and effectiveness of the ablative procedures were evaluated and compared with the chi-square test.

RESULTS

Ninety hypervascular HCCs, with a mean diameter of 2.6 cm (0.5-4.9 cm), underwent PEI (n=54) and RFTA (n=36). In the first group, CT identified complete necrosis in 28/54 (52%) lesions, 21 (75%) of which had avascular, one (4%) isovascular and six (21%) hypovascular patterns at CEUS. In the second group, CT showed complete necrosis in 31/36 (86%) lesions, all (100%) of which had a corresponding avascular pattern at CEUS. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the avascular pattern at CEUS compared with CT findings were 75%, 69%, 72%, 72% and 72% for PEI and 100%, 20%, 89%, 100% and 89%, for RFTA, respectively. A statistically significant difference (p<0.05) between the sensitivity of CEUS after PEI and after RFTA and between the necrosis obtained by RFTA and PEI were observed.

CONCLUSIONS

CEUS performed immediately after percutaneous ablation of hepatocellular carcinoma to evaluate treatment efficacy is compulsory in the case of RFTA but not for PEI.

Evaluation of colonic involvement in endometriosis: double-contrast barium enema vs. magnetic resonance imaging

BACKGROUND

The purpose of the study was to compare the accuracy of double-contrast barium enema (DCBE) and magnetic resonance imaging (MRI) in the diagnosis of intestinal endometriosis using the histological examination on resected specimen as comparative standard.

METHODS

Eighty-three consecutive patients with suspected intestinal endometriosis, resected between 2005 and 2007, were prospectively evaluated. All of the women underwent preoperative DCBE and MRI on the same day. We evaluated number, site (rectum, sigmoid, cecum), and size of the lesions. The imaging findings were correlated with those resulting at pathology.

RESULTS

Among the 65 women who underwent surgery, 50/65 (76.9%) were found to have bowel endometriosis, with 9/50 (18%) patients presenting two lesions; DCBE allowed to detect 50/59 (84.7%) lesions. MRI allowed to detect 42/59 (71.1%) lesions. DCBE showed sensibility, specificity, PPV, NPV, and accuracy of respectively 84.7, 93.7, 98.0, 62.5, and 86.6%, MRI of 71.1, 83.3, 93.3, 46.8, and 74.6%.

CONCLUSION

DCBE is more accurate than unenhanced MRI in the diagnosis of bowel endometriosis, and should be preferred in the preoperative management of this disease, since it usually enables a proper surgical planning.

Detection of focal liver lesions: from the subjectivity of conventional ultrasound to the objectivity of volume ultrasound

PURPOSE

This study was undertaken to establish the reliability of automated volumetric liver scans in detecting focal liver lesions by evaluating the degree of agreement between conventional and volume ultrasound (US) examinations.

MATERIALS AND METHODS

Over a period of 3 months, we prospectively studied 100 consecutive patients (36 men and 64 women; age range 15-87 years; mean age 63 years) referred to our institute for US imaging of the liver. Volumetric acquisition of the liver was achieved with a 3D transducer (2.0-5.0 MHz) and a Logiq 9 US scanner. All patients underwent both 2- and 3D US studies performed by two expert radiologists. Volumetric acquisitions were subsequently reviewed by the second radiologist, who was blinded to the first radiologist's report. Three categories were established: 1=presence of focal liver lesions; 2=doubtful finding; 3=absence of focal liver lesions. Concordance between volume US and conventional US was calculated by using the k statistic.

RESULTS

Out of 100 patients examined, 39 were found to be affected by focal liver lesions. All volume US examinations were technically adequate, allowing exploration of all hepatic sectors, except for five cases that were marred by major respiratory motion artefacts. Conventional and volume US identified the same number of focal liver lesions, with the exception of four cases of doubtful findings at volume US. Concordance between automated volume US and conventional US of the liver was high (k=0.92).

CONCLUSIONS

The identification of focal liver lesions on automated volume US is possible, and the examination shows a high level of concordance with conventional US.

Proper use of common image file formats in handling radiological images

This paper highlights the differences among the most common file formats used for storing digital radiological images. It promotes the proper use of these formats to guarantee easy manipulation in handling the most typical practical applications in daily radiological practice. The authors provide a simple yet exhaustive introduction to the concept of "file format" and describe the algorithms and main features of the most common formats (BMP, JPEG, GIF, DICOM, TIF, PNG) and Portable Network Graphics (PNG).The different formats are compared in terms of dimension, quality, portability and with reference to the following specific needs: electronic communications, publication on the World Wide Web, presentation of electronic posters, video presentations for teaching and manuscript publishing. We also illustrate how to handle the various formats with the programmes supplied with standard software installations.The large number of digital applications of image file formats calls for a simplification in daily radiological practice. We recommend the use of JPEG and PNG for electronic communications; PNG and GIF for publication on the worldwide web; JPEG and PNG for electronic poster presentations; DICOM, PNG and JPEG for teaching presentations; TIF and PNG for printing on paper.

Effect of a Static Magnetic Field (1.5T) on Brain Oscillatory Activities in Resting State Condition

The aim of the present study was to compare the EEG signal recorded outside and inside a 1.5T magnetic resonance (MR) scanner. The EEG was recorded in eyes open and eyes closed conditions using a digital recording MR-compatible system. To characterize how a static magnetic field induces changes in EEG signal, EEG data were analyzed using FFT frequency analysis. No significant difference between the alpha powers recorded outside and inside the magnetic field was observed in eyes closed conditions. However, in eyes open condition there was a significant increase in alpha power inside the magnet in comparison to the outside position. The changes in alpha power according to the eyes open/closed conditions could be inversely correlated to a subject's state of wakefulness and due to some physiological changes, rather than an effect of the magnetic field. This experiment suggests that subjects' state of wakefulness is of prime concern when performing functional MRI.

Increased fronto-temporal perfusion in bipolar disorder

OBJECTIVES

Previous imaging reports showed over-activation of fronto-limbic structures in bipolar patients, particularly in response to emotional stimuli. In this study, for the first time, we used perfusion weighted imaging (PWI) to analyze lobar cerebral blood volume (CBV) in bipolar disorder to further explore the vascular component to its pathophysiology.

METHODS

Fourteen patients with DSM-IV bipolar disorder (mean age+/-SD=49.00+/-12.30 years; 6 males, 8 females) and 29 normal controls (mean age+/-SD=45.07+/-10.30 years; 13 males, 16 females) were studied. PWI images were obtained following intravenous injection of paramagnetic contrast agent (Gadolinium-DTPA), with a 1.5 T Siemens magnet using an echo-planar sequence. The contrast of enhancement (CE), was calculated pixel by pixel as the ratio of the maximum signal intensity drop during the passage of contrast agent (Sm) by the baseline pre-bolus signal intensity (So) (CE=Sm/So*100) for frontal, temporal, parietal, and occipital lobes, bilaterally, on two axial images. Higher CE values correspond to lower CBV and viceversa.

RESULTS

Bipolar patients had significantly lower CE values in left frontal and temporal lobes (p=0.01 and p=0.03, respectively) and significantly inverse laterality index for frontal lobe (p=0.017) compared to normal controls. No significant correlations between CE measure and age or clinical variables were found (p>0.05).

CONCLUSION

This study found increased left frontal and temporal CBV in bipolar disorder. Fronto-temporal hyper-perfusion may sustain over-activation of these structures during emotion modulation, which have been observed in patients with bipolar illness.

MR imaging and MR cholangiopancreatography of multifocal intraductal papillary mucinous neoplasms of the side branches: MR pattern and its evolution

PURPOSE

This paper describes the magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) pattern of multifocal intraductal papillary mucinous tumours (IPMT) of the pancreatic side branches and its evolution during followup.

MATERIALS AND METHODS

Twenty-six patients with multifocal IPMT of the side branches were included in this retrospective study. Inclusion criteria were > or =2 ectasic side branches, presence of communication with the main pancreatic duct, and > or =2 MRI/MRCP examinations after > or = 6-12 months. Exclusion criteria were IPMT involving both the main pancreatic duct and its branch ducts, previous surgery and lack of follow-up MRI examinations. Median follow-up was 27 (range 6-59) months. Images were assessed qualitatively and quantitatively. Qualitative assessment considered: the number of cystic lesions of the branch ducts, morphology of the communication between the cystic lesion and the main duct (direct or neck), presence of intraluminal filling defects within the cystic lesions, presence of mural nodules and mural enhancement of the cystic lesion. quantitative assessment considered mean maximal diameter of the cystic lesions and mean length of the communication neck.

RESULTS

At diagnosis, the mean number of cystic lesions of the side branches was 7.5. a communication neck was detected in 16/26 patients (60%). Intraluminal filling defects in the side branches were present in 6/26 patients (23%). Mural nodules were seen in 1/26 patients (4%). The mean diameter of the cystic lesions was 18.8 mm. The mean length of the communication neck was 6.9 mm. At follow-up, the mean number of cystic lesions of the side branches was 8.4. A communication neck was detected in 20/26 patients (77%). Intraluminal filling defects in the side branches were detected in 7/26 patients (27%); mural nodules were seen in 2/26 patients (8%). Mural enhancement of the branch duct was detected in 2/26 patients (8%). The mean diameter of the cystic lesions increased to 22.3 mm (p < 0.05), and the mean length of the communication neck was 8.6 mm.

CONCLUSIONS

MultifocaL IPMT of the side branches shows a constant but very slow progression over time. In our series, only 2/26 patients showed mural nodules.

Bionic ear imaging

PURPOSE

The aim of this study was to illustrate the different imaging features of middle and inner ear implants, brainstem implants and inferior colliculus implants.

MATERIALS AND METHODS

We retrospectively reviewed the computed tomography (CT) images of 468 patients with congenital or acquired transmissive or neurosensory hearing loss who underwent surgery. The implants examined were: 22 Vibrant Soundbridge implants, 5 at the long limb of the incus and 17 at the round window, 350 cochlear implants, 95 brainstem implants and 1 implant at the inferior colliculus. All patients underwent a postoperative CT scan (single or multislice scanner) and/or a Dentomaxillofacial cone-beam CT scan (CBCT) (axial and multiplanar reconstruction), and/or a plain-film radiography to visualise the correct position of the implant.

RESULTS

The CBCT scan depicts Vibrant site of implant better than plain-film radiography, with a lower radiation dose compared to CT. For cochlear implants, a single plain radiograph in the Stenvers projection can directly visualise the electrodes in the cochlea. All patients with brainstem or inferior colliculus implants underwent postoperative CT to exclude complications and the assess correct implantation, but the follow-up of these implants can be performed by plain radiography alone.

CONCLUSIONS

CT and CBCT scans are reliable and relatively fast methods for precisely determining the location of middle ear implants. CBCT is preferable to CT because of the lower radiation dose administered; a single plain-film radiograph is enough to visualise and follow-up cochlear, brainstem and inferior colliculus implants.

Continuous EEG-fMRI in Pre-Surgical Evaluation of a Patient with Symptomatic Seizures: Bold Activation Linked to Interictal Epileptic Discharges Caused by Cavernoma

We used continuous electroencephalography-functional magnetic resonance imaging (EEG-fMRI) to identify the linkage between the “epileptogenic” and the “irritative” area in a patient with symptomatic epilepsy (cavernoma, previously diagnosed and surgically treated), i.e. a patient with a well known “epileptogenic area”, and to increase the possibility of a non invasive pre-surgical evaluation of drug-resistant epilepsies. A compatible MRI system was used (EEG with 29 scalp electrodes and two electrodes for ECG and EMG) and signals were recorded with a 1.5 Tesla MRI scanner. After the recording session and MRI artifact removal, EEG data were analyzed offline and used as paradigms in fMRI study. Activation (EEG sequences with interictal slow-spiked-wave activity) and rest (sequences of normal EEG) conditions were compared to identify the potential resulting focal increase in BOLD signal and to consider if this is spatially linked to the interictal focus used as a paradigm and to the lesion. We noted an increase in the BOLD signal in the left neocortical temporal region, laterally and posteriorly to the poro-encephalic cavity (residual of cavernoma previously removed), that is around the “epileptogenic area”. In our study “epileptogenic” and “irritative” areas were connected with each other. Combined EEG-fMRI may become routine in clinical practice for a better identification of an irritative and lesional focus in patients with symptomatic drug-resistant epilepsy.

Ultrasonography of the pancreas. 4. Contrast-enhanced imaging

The introduction of contrast-enhanced ultrasonography (CEUS) has lead to great developments in the diagnostic capabilities of ultrasound. Second generation contrast media, characterized by harmonic responses at low mechanical index of the ultrasound beam, have already proven usefulness in the study of the liver but other abdominal organs can take advantage from the dynamic study during continuous ultrasonographic scans. The dynamic observation of the enhancement allows the perfect evaluation of the abdominal organs perfusion. The perfusion of the pancreas is well correlated to the semeiology of the gland parenchymography at CEUS. The study of the pancreas is a new and promising application of CEUS. CEUS can be used to better identify pancreatic lesions respect to conventional Ultrasound (US) or to characterize pancreatic lesions already visible at US. Moreover the staging of some pancreatic lesions can be improved by the use of contrast media. This article will review the clinical application of CEUS in the different pancreatic pathologies.

Ultrasonography of the pancreas. 3. Doppler imaging

Ultrasonography is probably the most widely used medical imaging technique. In fact, its non-invasivity, portability, widespread distribution and good clinical results have made it the preferred method for a first imaging approach to patients in a large variety of clinical settings. Ultrasound technology is advancing rapidly, aimed to increase image quality. In particular, increased color-Doppler sensitivity is contributing to the diagnosis and staging of pancreatic disease. Doppler studies are in fact integral part of ultrasound examination of the pancreas evaluating the peripancreatic vascular structures enclose portal vein, splenic artery and vein, superior mesenteric artery and vein, aorta, and inferior vena cava. While flows in all peri-pancreatic vessels are well recognized, only few parenchymal vessels are usually appreciable in normal conditions. Anyway the increased Doppler sensitivity allows the visualization of smaller peri-pancreatic and intra-pancreatic vessels. This article will review the technical background underlying the clinical application of Doppler ultrasonography in pancreatic imaging, with particular emphasis to normal vascular anatomy of the pancreas, and to the main applications of Doppler techniques in the different pancreatic pathologies.

Endovascular treatment of arterial bleeding in patients with pancreatitis

PURPOSE

To assess the technical and clinical success of endovascular treatment of arterial bleeding in pancreatitis.

MATERIALS AND METHODS

From 1992 to 2005, 28 patients with pancreatitis underwent endovascular treatment of associated arterial lesions. Fifteen patients were affected by acute pancreatitis and 13 by chronic pancreatitis. The diagnosis was obtained according to medical history and clinical and laboratory evidence of disease. Arterial involvement was diagnosed by non-invasive imaging and angiography. After treatment, all patients underwent CT scanning at a minimum of 15, 30 and 90 days. We evaluated the feasibility of embolization and patients' survival at 90 days.

RESULTS

Transcatheter embolization was feasible in 26/28 patients (93%). In 2 patients with acute pancreatitis, selective catheterization failed so we could not proceed with the angiographic approach. After treatment, there were 3/26 rebleeds (11.5%), all of whom died within the first week. At 90 days' follow-up, 21/26 patients (81%) were alive. Two of 26 patients (8%) suffered splenic complications. Among the 13 patients with acute pancreatitis, 8 (61.5%) were alive after 90 days. All 13 patients with chronic pancreatitis were alive after 90 days.

CONCLUSIONS

Comparing our results with the surgical literature, we found that embolization is less invasive and, at least, as successful as surgery. Thus, it should be considered the first choice in pancreatitis arterial complications.

Autologous chondrocyte implantation: Prospective MRI evaluation with clinical correlation

PURPOSE

This study was done to assess the progression of cartilage repair after autologous chondrocyte implantation (ACI) with magnetic resonance imaging (MRI) and to correlate the findings with the clinical outcome.

MATERIALS AND METHODS

Forty-one patients (mean age 30 years) affected by chondral defects of the knee (27 patients) and ankle joint (14 patients) who underwent arthroscopic autologous osteochondral grafting were studied 6 months and 1 year postoperatively with MRI. Cartilage repair after chondrocyte implantation was studied by assessing the degree of defect filling, graft integration, graft signal intensity, integrity of the subchondral lamina and trabecular oedema underneath the graft. MR findings were correlated with clinical data.

RESULTS

Postoperative MRI evaluation at 6 months demonstrated complete filling of the osteochondral defect in 12/41 cases, complete integration in 18/41, mild hyperintensity in 28/41, intact subchondral lamina in 38/41 and trabecular oedema in 11/41. Postoperative MRI evaluation at 1 year demonstrated complete filling of the osteochondral defect in 9/41 patients, complete integration in 22/41, mild hyperintensity in 23/41, intact subchondral lamina in 36/41 and trabecular oedema in 8/41. Filling of the osteochondral defect and incomplete integration, nonintact subchondral lamina, high signal intensity and absence of oedema were found to correlate with worse clinical-functional outcomes.

CONCLUSIONS

MRI shows direct prognostic signs of the clinical outcome of ACI.