Le alterazioni del segnale RM nell'encefalo dell'anziano: Correlazioni anatomopatologiche

Numerosi lavori sottolineano la frequente incidenza di focolai di iperintensita' di segnale nell'encefalo di soggetti anziani pur in assenza di evidenti substrati clinici. É stata inoltre sottolineata la frequente incidenza di dilatazioni degli spazi perivascolari e di infarti lacunari, in valutazioni effettuate su preparati autoptici fissati in formalina.

Abbiamo voluto verificare su 20 encefali prelevati da soggetti anziani non fissati in formalina l'incidenza delle alterazioni suddette, le caratteristiche differenziali e le modificazioni relative al successivo fissaggio. La nostra esperienza ha rilevato la presenza di foci di iperintensita nel 45% dei preparati sottolineando la possibile presenza di lesioni vascolari piu' grossolane misconosciute durante la vita. L'incidenza di dilatazioni perivascolari è in leggero difetto rispetto a quella delle lesioni lacunari, con distribuzione prevalente di entrambe nei gangli della base (39%), concordando con quanto espresso da altri autori.

Si è osservato, tuttavia come la frequente coesistenza di lacune e dilatazioni perivascolari renda spesso impossibile la differenziazione tra le due entità. Inoltre it nostro studio sottolinea come la valutazione dopo fissaggio in formalina determini una sovrastima delle lesioni osservabili, verosimilmente in relazione a «raggrinzimento» tissutale da processo di disidratazione.

Risk management in radiology

Recent US nationwide research on malpractice lawsuits shows that the most common cause of medical malpractice suits against radiologists was error in diagnosis (mainly failure to diagnose instead of delay); the category next in frequency was procedural complications, followed by inadequate communication with either patient or referring physician. Risk management is a fundamental instrument to prevent and limit errors and adverse events. This article analyzes risk management in radiology addressing the most common ethical-legal issues on appropriateness of prescriptions, informed consent, and management of adverse events. Effective remedial actions are proposed to avoid malpractice claims that would help physicians in preventing malpractice stress syndrome, leading to defensive medicine.

Osteoid osteoma: MR-guided focused ultrasound for entirely noninvasive treatment

PURPOSE

To determine the preliminary feasibility, safety, and clinical efficacy of magnetic resonance (MR)-guided focused ultrasound for the treatment of painful osteoid osteoma.

MATERIALS AND METHODS

This prospective institutional review board-approved study involved six consecutive patients (five males and one female; mean age, 21 years) with a diagnosis of osteoid osteoma based on clinical and imaging findings. All patients underwent MR-guided focused ultrasound ablation after providing informed consent. Lesions located in the vertebral body were excluded. The number of sonications and the energy deposition were recorded. Treatment success was determined at 1, 3, and 6 months after treatment. A visual analog scale (VAS) score for pain was used to assess changes in symptoms. MR imaging features of osteoid osteoma (edema, hyperemia, and nidus vascularization) were considered at baseline and at imaging follow-up.

RESULTS

Treatment was performed with a mean of 4 sonications ± 1.8 (standard deviation), with a mean energy deposition of 866 J ± 211. No treatment- or anesthesia-related complications occurred. The pre- and posttreatment mean VAS scores significantly differed (7.9 ± 1.4 and 0.0 ± 0.0, respectively). At imaging, the edema and hyperemia associated with osteoid osteoma gradually disappeared in all lesions. However, nidus vascularization still persisted after treatment in four of six patients.

CONCLUSION

This limited series demonstrated that MR-guided focused ultrasound treatment of osteoid osteoma can be performed safely with a high rate of success and without apparent treatment-related morbidity.

Use of multiparametric MR with neurovascular bundle evaluation to optimize the oncological and functional management of patients considered for nerve-sparing radical prostatectomy

INTRODUCTION

To obtain the best results with radical prostatectomy, either from an oncological or a functional point of view, a correct selection of cases and planning of surgery are crucial. Multiparametric magnetic resonance imaging (MRI) promises to make it a successful imaging tool for improving many aspects of prostate cancer management.

AIM

The aim of this study is to evaluate whether a modern multiparametric MRI can help either to better select prostate cancer cases for a nerve-sparing radical prostatectomy or to improve the functional evaluation related to neurovascular bundles preservation.

MAIN OUTCOME MEASURES

The effect of preoperative MRI on neurovascular bundle management was examined for the frequency and the appropriateness of changes of the surgical plane on the basis of MRI indications.

METHODS

In a prospective study, 125 consecutive patients with biopsy proven prostate cancer who were scheduled to undergo bilateral nerve-sparing surgery. All patients included into the study were submitted to a preoperative multiparametric MRI. On the basis of MRI evaluation, patients were divided into two groups. Patients in group A were then submitted to a bilateral nerve-sparing (NS) radical prostatectomy (RP), whereas patients in group B were submitted to unilateral NS or non-NS RP.

RESULTS

In group A, the confirmation from the MRI study to perform a bilateral NS procedure was appropriate in 70 of 73 cases (95.9%), whereas in group B, the surgical plan was appropriate in 28 of 32 cases (87.5%). On the contrary, MRI findings suggested a change in the initial surgical plan (group B) for 32 of 105 cases (30.5%). Of these 32 cases in group B, MRI suggested to perform a unilateral NS procedure in 21 of 32 cases (65.6%) and a non-NS procedure in 11 of 32 cases (34.4%).

CONCLUSIONS

Multiparametric MRI analysis can significantly improve the standard selection and management of prostate carcinoma cases considered for an NS RP.

Effect of varying contrast material iodine concentration and injection technique on the conspicuity of hepatocellular carcinoma during 64-section MDCT of patients with cirrhosis

OBJECTIVES

The aim of this study was to compare the intraindividual effects of contrast material with two different iodine concentrations on the conspicuity of hepatocellular carcinoma (HCC) and vascular and hepatic contrast enhancement during multiphasic, 64-section multidetector row CT (MDCT) in patients with cirrhosis using two contrast medium injection techniques.

METHODS

Patients were randomly assigned to one of two groups with an equal iodine dose but different contrast material injection techniques: scheme A, fixed injection duration (25 s), and scheme B, fixed injection flow rate (4 ml s(-1)). For each group, patients were randomised to receive both moderate-concentration contrast medium (MCCM) and high-concentration contrast medium (HCCM) during two CT examinations within 3 months. Enhancement of the aorta, liver and portal vein and the tumour-to-liver contrast-to-noise ratio (CNR) were compared between MCCM and HCCM.

RESULTS

30 patients (mean age 59 years; range 45-80 years; 16 patients in scheme A and 14 in scheme B) with a total of 31 confirmed HCC nodules were prospectively enrolled. For scheme B, the mean contrast enhancement of the aorta and tumour-to-liver CNR were significantly higher with HCCM than with MCCM during the hepatic arterial phase (+350.5 HU vs +301.1 HU, p = 0.001, and +7.5 HU vs +5.5 HU, p = 0.004). For both groups, there was no significant difference between MCCM and HCCM for all other comparisons.

CONCLUSION

For a constant injection flow rate, HCCM significantly improves the conspicuity of HCC lesions and aortic enhancement during the hepatic arterial phase on 64-section MDCT in patients with cirrhosis.

Low-dose contrast-enhanced time-resolved MR angiography at 3T: diagnostic accuracy for treatment planning and follow-up of vascular malformations

AIM

To assess the accuracy of low-dose contrast-enhanced time-resolved 3T magnetic resonance angiography (MRA) for the morphological and functional assessment of vascular malformations (VM), and to evaluate its diagnostic potential for the depiction of treatment-induced changes.

MATERIALS AND METHODS

Twenty-five patients with known VM underwent MRA to evaluate the location and extent of lesions and their haemodynamic characteristics. Three-dimensional (3D) T1-weighted time-resolved sequences were acquired following the administration of 0.05mmol/kg of gadobenate dimeglumine. VM were classified according to their morphology and haemodynamic characteristics. All patients thereafter underwent conventional angiography to confirm the diagnosis and to treat the lesions (embolization or sclerotherapy). Follow-up MRA was performed 30 days after treatment to assess morphological and functional changes. A visual analogue scale (VAS) was used to clinically assess the severity of symptoms before and after therapy.

RESULTS

Based on haemodynamic characteristics, VM were classified as predominantly arterial [4 (16%)], artero-venous [19 (76%)] or venous [2 (8%)]. Twenty-three (92%) lesions were classified as high-flow VM and two (8%) as low-flow VM. Intralesional thrombosis was present in 17 (68%) lesions before therapy and in 10 lesions (40%) after therapy. The median VAS scores were 5±1 before treatment and 4±2 after treatment. Very good correlation (Spearman's correlation coefficient: rho=0.87; p=0.000) was noted between the reduction of lesion size on follow-up MRA and pain relief as assessed by VAS.

CONCLUSION

Low-dose contrast-enhanced time-resolved 3T MRA can be used to define morphological and functional aspects of VM accurately during treatment planning and follow-up, and can identify post-therapy changes that positively correlate with treatment outcome.

Adolescent Kawasaki disease: usefulness of 64-slice CT coronary angiography for follow-up investigation

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis that mainly affects coronary arteries in children, and requires regular follow-up from the time of diagnosis.

OBJECTIVE

To evaluate the feasibility of 64-slice CT angiography (CTA) for follow-up of patients with KD using previously performed invasive catheter coronary angiography (CCA) as reference standard.

MATERIALS AND METHODS

The study group comprised 12 patients (age 17.6 ± 2.9 years, mean ± SD) with a diagnosis of KD and a previously performed CCA (interval, 32.6 ± 13.5 months) who underwent 64-slice cardiac CTA. The quality of the images for establishing the presence of coronary abnormalities was determined by two observers. The CTA findings were compared with those from the prior CCA.

RESULTS

Adequate image quality was obtained in all patients. Mean effective dose for CTA was 6.56 ± 0.95 mSv. CTA allowed accurate identification, characterization and measurement of all coronary aneurysms (n = 32), stenoses (n = 3) and occlusions (n = 9) previously demonstrated by CCA. One patient with disease progression went on to have percutaneous coronary intervention.

CONCLUSION

Coronary lesions were reliably evaluated by 64-slice CTA in the follow-up of compliant patients with KD, reducing the need for repeated diagnostic invasive CCA. Hence, in an adequately selected patient population, the role of CCA could be limited almost only to therapeutic procedures.

Malignant tumours of the small intestine: a review of histopathology, multidetector CT and MRI aspects

Small bowel neoplasms, including adenocarcinoma, carcinoid tumour, lymphoma and gastrointestinal stromal tumours, represent a small percentage of gastrointestinal cancers, yet are among those with the poorest prognosis compared with other gastrointestinal malignancies. Unclear clinical scenarios and difficult radiological diagnosis often delay treatment with negative effects on patient survival. Recently, multidetector CT (MDCT) and MRI have been introduced as feasible and accurate diagnostic techniques for the identification and staging of small bowel neoplasms. These techniques are gradually replacing conventional barium radiography as the tool of choice. However, the inherent technical and physiological challenges of small bowel imaging require a familiarity with patient preparation and scan protocols. Adequate knowledge of the histopathology and natural evolution of small bowel neoplasms is also important for differential diagnosis. The aim of this article is to review MDCT and MRI protocols for the evaluation of small bowel tumours and to provide a concise yet comprehensive guide to the most relevant imaging features relative to histopathology.

PCA3 urinary test versus 1H-MRSI and DCEMR in the detection of prostate cancer foci in patients with biochemical alterations

AIM

To compare the prostate antigen 3 (PCA3) test with (1)H-magnetic resonance spectroscopic imaging ((1)H-MRSI) and dynamic contrast-enhanced magnetic resonance imaging (DCEMR) combined examination in the detection of prostate tumor foci in patients with persistently elevated prostate-specific antigen (PSA) levels and prior negative random transrectal ultrasound (TRUS)-guided biopsy.

PATIENTS AND METHODS

Forty-three patients with a first random biopsy negative for prostate adenocarcinoma, persistent elevated PSA and negative digital rectal examination were recruited. All the patients were submitted to MRSI examination (MRSI-DCEMR) and were submitted to an attentive prostate massage in order to perform PCA3 assay. Afterwards, 10-core laterally-directed random TRUS-guided prostate biopsy was performed.

RESULTS

The overall sensitivity and specificity of a PCA3 score ≥35 for positive biopsy were 76.9% and 66.6%, respectively, with a positive predictive value (PPV) of 80% and a negative predictive value (NPV) of 62.5%; as for MRSI sensitivity and specificity were, respectively, 92.8% and 86.6% with a PPV of 92.8% and a NPV of 86.6%. Receiver operating characteristic (ROC) analysis rates were 0.755 for PCA3 and 0.864 for MRSI.

CONCLUSION

Combined MRSI/DCEMR can better improve the cancer detection rate in patients with prior negative TRUS-guided biopsy and altered PSA serum levels than PCA3. Optimization of MRSI will allow more precise diagnosis of local invasion and improved bioptical procedures.

Incidental enhancing lesions found on preoperative breast MRI: management and role of second-look ultrasound

PURPOSE

This study prospectively assessed second-look ultrasound (US) for the evaluation of incidental enhancing lesions identified on preoperative breast magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Between 2004 and 2007, 182 patients with malignant breast lesions detected on US and/or X-ray mammography and confirmed by cytology/histology underwent preoperative breast contrast-enhanced (CE)-MRI. Patients with incidental lesions on breast MRI underwent second-look high-resolution US directed at the site of the incidental finding. Diagnosis of incidental lesions was based on biopsy or 24-month follow-up.

RESULTS

Breast MRI detected 55 additional lesions in 46/182 (25.2%) patients. Forty-two of 55 (76.3%) lesions were detected on second-look US in 38/46 (82.6%) patients. Malignancy was confirmed for 24/42 (57.1%) correlate lesions compared with 7/13 (53.8%) noncorrelate lesions. Second-look US depicted 8/9 (88.8%) Breast Imaging Reporting and Data System (BI-RADS) 5, 16/22 (72.7%) BI-RADS 4 and 18/24 (75%) BI-RADS 3 lesions. Sensitivity, specificity, accuracy and positive and negative predictive values for lesion detection/diagnosis was 100%, 88.9%, 94.6%, 90.3% and 100% for MRI and 64.3%, 70.4%, 67.3%, 69.2% and 65.5% for second-look US. Improved performance for US was obtained when masslike lesions only were considered.

CONCLUSIONS

Second-look US is a confirmatory method for incidental findings on breast MRI, particularly for mass-like lesions.

Chlamydophila pneumoniae infection in patients undergoing carotid artery stent

Although several reports have correlated Chlamydophila pneumoniae (CP) infection with carotid endarterectomy and coronary stent, no data have been reported on the potential relationship between this pathogen and carotid artery stenting (CAS). Hence, we evaluated 47 subjects, 27 symptomatic and 20 asymptomatic, before CAS intervention and during the follow up, for the presence of CP DNA and anti-CP antibodies, including chlamydial HSP60 (Cp-HSP60). Before stent placement, CP DNA was detected exclusively in symptomatic patients, all of whom were also positive for CP IgG and IgA and 85.7 percent of them also had CP-HSP60 antibodies. At the follow-up, all CP DNA positive and 11 out of the 13 symptomatic patients with Cp-HSP60 antibodies became negatives. In contrast, no change was observed for CP- IgA antibodies. Despite the small number of patients, the present study advocates an important role of CP infection in symptomatic patients with carotid artery disease. Our findings also suggest that stent placement and/or therapy might have a role in favouring resolution of inflammation, though not affecting persistence of CP infection.

Pathologic findings in synovial tissue of the musculoskeletal system: role of MRI in therapeutic clinic assessment

OBJECTIVES

The clinical diagnosis of synovial lesions is difficult and radiographic findings may establish a confident diagnosis only in some cases. MR imaging has become the technique of choice in evaluating these lesions, because a presumptive diagnosis can be made in most cases. The purpose of this study was to evaluate the joint synovial disease through intravenous contrast MRI examination and the following histological validation.

MATERIALS AND METHODS

Forty-eight patients were considered, twenty-seven women and twenty-one men, with pain relief or collectively determined by a known joint synovial disease, who underwent MRI at our institution between 2000 and the second half of 2010. All patients underwent magnetic resonance imaging using a low field magnet (0.2 Tesla) or high field magnet (1,5Tesla).

RESULTS

Only nine patients were diagnosed with an inflammatory arthropathy, in the remaining cases non-inflammatory arthropathy of which the most frequent form was pigmented villonodular synovitis (PVNS) was diagnosed.

CONCLUSIONS

MRI is able to provide an accurate representation of all the pathological changes involved in the joint space following acute or chronic inflammation and to define the characteristic features useful in differential diagnosis.

Utility of T2-weighted short-tau inversion recovery (STIR) sequences in cardiac MRI: an overview of clinical applications in ischaemic and non-ischaemic heart disease

T2-weighted short-tau inversion recovery (T2w-STIR) imaging is the best approach for oedema-weighted cardiac magnetic resonance imaging (MRI), as it suppresses the signal from flowing blood and from fat and enhances sensitivity to tissue fluid. The purpose of this pictorial review is to illustrate the clinical use and application of this technique in various ischaemic and non-ischaemic conditions. In ischaemic heart disease, T2w-STIR represents the technique of choice for detecting oedema in patients with acute myocardial infarction (MI), allowing discrimination of acute and chronic injuries. Myocardial haemorrhage may also be depicted as a region of signal abnormality characterised by a central hypointense core with a peripheral hyperintense rim, presumably reflecting the presence of intracellular methaemoglobin within the necrotic area. In the acute setting, elevated T2 relaxation times in association with regional contractile dysfunction but no signs of delayed enhancement may also signify a reversible ischaemic injury without necrosis. In acute myocarditis, the distribution pattern of T2w hyperintensity may be focal in approximately 30% of patients or diffuse in the remaining 70%, and myocardial oedema may be the only marker of disease. Tissue oedema may also be observed in various other conditions, such as primary cardiomyopathies (CMP), storage disease, pulmonary hypertension and cardiac transplant rejection. T2w-STIR represents an appealing and versatile technique that can be applied in a wide variety of ischaemic and non-ischaemic conditions, allowing detection of segmental or global increase of myocardial free water content, reflecting an acute myocardial injury.

Detection of hepatic metastases from colorectal cancer: prospective evaluation of gray scale US versus SonoVue® low mechanical index real time-enhanced US as compared with multidetector-CT or Gd-BOPTA-MRI

PURPOSE

To compare ultrasound (US), low-mechanical index contrast enhanced US (CEUS) and multidetector-CT (MDCT) for the detection of hepatic metastases from colorectal cancer.

METHODS AND MATERIALS

From January to June 2006, 110 patients (65 males, 45 females; mean age 62 years; range 39-78) with suspected hepatic lesions from colorectal cancer were prospectively evaluated with US, CEUS and MDCT by two independent readers. Intraoperative ultrasonography (IOUS, n = 45) or a follow-up up for at least 6 months by using MDCT or Gd-BOPTA-enhanced MRI was considered the gold standard. McNemar test was employed.

RESULTS

Reference standards revealed 430 metastases in 110 patients. On a patient-by-patients analysis, CEUS improved US sensitivity from 67.4-71.6% to 93.4-95.8% (p < 0.05). On a lesion-by-lesion analysis, CEUS improved the sensitivity of US from 60.9-64.9% to 85.3-92.8% (p < 0.001). The specificity increased from 50-60% to 76.7-83.3%. No significant differences in sensitivity or specificity between CEUS and MDCT were found. Contrast-enhanced US was significantly more sensitive than baseline US in the detection of metastases smaller than 1 cm (p < 0.001) with an increase in sensitivity from 29.1-35% to 63.3-76.6% no significant statistical difference was identified when compared with MDCT (sensitivity of 73.3-75.8%).

CONCLUSIONS

CEUS is significantly more accurate than US and highly comparable with MDCT in the detection of liver metastases from colorectal cancer. Therefore, in the evaluation of patients with suspected hepatic metastases from colorectal tumour, US examination must be performed after contrast administration.

Intraindividual comparison of gadoxetate disodium-enhanced MR imaging and 64-section multidetector CT in the Detection of hepatocellular carcinoma in patients with cirrhosis

PURPOSE

To prospectively compare gadoxetate disodium-enhanced magnetic resonance (MR) imaging with multiphasic 64-section multidetector computed tomography (CT) in the detection of hepatocellular carcinoma (HCC) in patients with cirrhosis.

MATERIALS AND METHODS

Institutional review board approval and informed patient consent were obtained for this prospective study. Fifty-eight patients (39 men, 19 women; mean age, 63 years; age range, 35-84 years) underwent gadoxetate disodium-enhanced MR imaging and multiphasic 64-section multidetector CT. The imaging examinations were performed within 30 days of each other. The two sets of images were qualitatively analyzed in random order by three independent readers in a blinded and retrospective fashion. Using strict diagnostic criteria for HCC, readers classified all detected lesions with use of a four-point confidence scale. The reference standard was a combination of pathologic proof, conclusive imaging findings, and substantial tumor growth at follow-up CT or MR imaging (range of follow-up, 90-370 days). The diagnostic accuracy, sensitivity, and positive predictive value were compared between the two image sets. Interreader variability was assessed. The accuracy of each imaging method was determined by using an adjusted modified chi(2) test.

RESULTS

Eighty-seven HCCs (mean size +/- standard deviation, 1.8 cm +/- 1.5; range, 0.3-7.0 cm) were confirmed in 42 of the 58 patients. Regardless of lesion size, the average diagnostic accuracy and sensitivity for all readers were significantly greater with gadoxetate disodium-enhanced MR imaging (average diagnostic accuracy: 0.88, 95% confidence interval [CI]: 0.80, 0.97; average sensitivity: 0.85, 95% CI: 0.74, 0.96) than with multidetector CT (average diagnostic accuracy: 0.74, 95% CI: 0.65, 0.82; average sensitivity: 0.69, 95% CI: 0.59, 0.79) (P < .001 for each). No significant difference in positive predictive value was observed between the two image sets for each reader. Interreader agreement was good to excellent.

CONCLUSION

Compared with multiphasic 64-section multidetector CT, gadoxetate disodium-enhanced MR imaging yields significantly higher diagnostic accuracy and sensitivity in the detection of HCC in patients with cirrhosis.

Magnetic resonance spectroscopic imaging (1H-MRSI) and dynamic contrast-enhanced magnetic resonance (DCE-MRI): pattern changes from inflammation to prostate cancer

PURPOSE

To assess (1)H-magnetic resonance spectroscopic imaging ((1)H-MRSI) and dynamic contrast-enhanced magnetic resonance (DCE-MRI) features in histologically confirmed prostatic chronic inflammation, prostatic intraepithelial neoplasia (PIN), low grade prostate cancer (LGPCa), and high grade prostate cancer (HGPCa).

MATERIALS AND METHODS

Ninety-six men were selected, who showed at histology a diagnosis of chronic inflammation (Group B), high grade (HG) PIN (Group C), or prostate cancer (LGPCa = Group D and HGPCa = Group E).

RESULTS

ANOVA analysis shows that inflammation (Group B) displays no significantly (p >.05) different choline and citrate levels when compared to HGPIN and LGPCa.

CONCLUSION

our results suggest the potential for these MR imaging techniques in the description of inflammatory and proliferative lesions inside the prostate gland.

Morpho-functional patterns of physiologic oropharyngeal swallowing evaluated with dynamic fast MRI

With the advent of dynamic fast MRI sequences the act of deglutition can be dynamically visualized in cine-mode. Twenty-three healthy volunteers were enrolled in this study to define the morpho-functional patterns of oral and pharyngeal deglutition using new dynamic MRI techniques. All subjects were previously submitted to video endoscopic assessment, to exclude swallowing abnormalities. As contrast material a combination of yogurt mixed with gadolinium-diethylene diamine pentaacetic acid was used. The protocol was divided into three parts: (a) preliminary assessment of the oral cavity, pharynx and laryngeal structures; (b) morphologic assessment of tongue, soft palate, pharynx, epiglottis and larynx-hyoid bone; (c) dynamic assessment of swallowing without administrating any contrast media and, in subsequent phase, by injecting 5 ml of yogurt-based contrast medium in the patient's mouth. The time resolution was 3-4 images/s. The MR protocol revealed to be effective in the evaluation of normal motility patterns of the structures involved in swallowing. Moreover, the evaluation of the bolus progression, slowdown or stagnation, was possible. On the contrary problems were encountered in calculating precisely the bolus progression time, because of the insufficient temporal resolution. However, more energy should be invested to optimize the spatial and temporal resolution of turbo-FLASH sequences, to obtain a better dynamic representation of a complex function such as deglutition.

Value of magnetic resonance spectroscopy imaging and dynamic contrast-enhanced imaging for detecting prostate cancer foci in men with prior negative biopsy

PURPOSE

This study aimed to prospectively analyze the role of magnetic resonance spectroscopy imaging (MRSI) and dynamic-contrast enhancement magnetic resonance (DCEMR) in the detection of prostate tumor foci in patients with persistently elevated prostate-specific antigen levels (in the range of >or=4 ng/mL to <10 ng/mL) and prior negative random trans-rectal ultrasound (TRUS)-guided biopsy.

EXPERIMENTAL DESIGN

This was a prospective randomized single-center study. One hundred and eighty eligible cases were included in the study. Patients in group A were submitted to a second random prostate biopsy, whereas patients in group B were submitted to a (1)H-MRSI-DCEMR examination and samples targeted on suspicious areas were associated to the random biopsy.

RESULTS

At the second biopsy, a prostate adenocarcinoma histologic diagnosis was found in 22 of 90 cases (24.4%) in group A and in 41 of 90 cases (45.5%) in group B (P = 0.01). On a patient-by-patient basis, MRSI had 92.3% sensitivity, 88.2% specificity, 85.7% positive predictive value (PPV), 93.7% negative predictive value (NPV), and 90% accuracy; DCEMR had 84.6 % sensitivity, 82.3% specificity, 78.5% PPV, 87.5% NPV, and 83.3% accuracy; and the association MRSI plus DCEMR had 92.6% sensitivity, 88.8% specificity, 88.7% PPV, 92.7% NPV, and 90.7% accuracy, for predicting prostate cancer detection.

CONCLUSIONS

The combination of MRSI and DCEMR showed the potential to guide biopsy to cancer foci in patients with previously negative TRUS biopsy. To avoid a potential bias, represented from having taken more samples in group B (mean of cores, 12.17) than in group A (10 cores), in the future a MRSI/DCEMR directed biopsy could be prospectively compared with a saturation biopsy procedure.

CAD (computed-aided detection) and CADx (computer aided diagnosis) systems in identifying and characterising lung nodules on chest CT: overview of research, developments and new prospects

Computer-aided detection (CAD) systems allow the automatic identification of lung nodules on chest computed tomography (CT), providing a second opinion to the radiologist's judgement and a volumetric evaluation of lesions - a very important aspect in oncological patients. The natural evolution of these systems has led to the introduction of computer-aided diagnosis (CADx) systems, which are able not only to identify nodules but also to characterise them by determining a likelihood of malignancy or benignity. The aim of this article is to describe the main technical principles of CAD and CADx systems, their applicability and influence in clinical practice and new prospects for their future development.

Impact of primary coronary angioplasty delay on myocardial salvage, infarct size, and microvascular damage in patients with ST-segment elevation myocardial infarction: insight from cardiovascular magnetic resonance

OBJECTIVES

We investigated the extent and nature of myocardial damage by using cardiovascular magnetic resonance (CMR) in relation to different time-to-reperfusion intervals.

BACKGROUND

Previous studies evaluating the influence of time to reperfusion on infarct size (IS) and myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI) have yielded conflicting results.

METHODS

Seventy patients with STEMI successfully treated with primary percutaneous coronary intervention within 12 h from symptom onset underwent CMR 3 +/- 2 days after hospital admission. Patients were subcategorized into 4 time-to-reperfusion (symptom onset to balloon) quartiles: < or =90 min (group I, n = 19), >90 to 150 min (group II, n = 17), >150 to 360 min (group III, n = 17), and >360 min (group IV, n = 17). T2-weighted short tau inversion recovery and late gadolinium enhancement CMR were used to characterize reversible and irreversible myocardial injury (area at risk and IS, respectively); salvaged myocardium was defined as the normalized difference between extent of T2-weighted short tau inversion recovery and late gadolinium enhancement.

RESULTS

Shorter time-to-reperfusion (group I) was associated with smaller IS and microvascular obstruction and larger salvaged myocardium. Mean IS progressively increased overtime: 8% (group I), 11.7% (group II), 12.7% (group III), and 17.9% (group IV), p = 0.017; similarly, MVO was larger in patients reperfused later (0.5%, 1.5%, 3.7%, and 6.6%, respectively, p = 0.047). Accordingly, salvaged myocardium markedly decreased when reperfusion occurred >90 min of coronary occlusion (8.5%, 3.2%, 2.4%, and 2.1%, respectively, p = 0.004).

CONCLUSIONS

In patients with STEMI treated with primary percutaneous coronary intervention, time to reperfusion determines the extent of reversible and irreversible myocardial injury assessed by CMR. In particular, salvaged myocardium is markedly reduced when reperfusion occurs >90 min of coronary occlusion.

Is pattern III as evidenced by US color-Doppler useful in predicting thyroid nodule malignancy? Large-scale retrospective analysis

OBJECTIVE

To evaluate whether pattern III of color Doppler Ultra-sound may identify malignant nodules.

MATERIALS AND METHODS

We have retrospectively analyzed data pertaining to 1090 patients of both genders (230 males, 860 females), with an average age of 53 years (min 17 years, max 81 years), who underwent thyroidectomy in Department of Surgical Sciences of Sapienza University of Rome since January 2003 through June 2009. We correlated color-Doppler characteristics and histological features through statistical analysis so as to verify statistical correlation between them.

RESULTS

Our study showed that 164/273 (60.1%) patients with malignant disease were associated with vascularization pattern III. Regarding benign disease, 152/268 (56.7%) patients showed a pattern of vascularization 3 at ultrasonography. The statistical analysis was not able to show any correlation between pattern III and malignancy.

CONCLUSION

Pattern III cannot be used to predict malignancy with confidence, and FNA is still mandatory to rule out the nature of the nodule.

Limiting Complications During Carotid Artery Stenting in Complex Lesions

Stroke is the third leading cause of death and permanent disability in the US and Europe. During the last decade, carotid artery stenting (CAS) has gained a role as an alternative option to carotid endoarterectomy (CEA). Both patient selection and plaque morphology are crucial to reduce the risk of complications. Technical aspects such as the employment and selection of different types of cerebral protection devices, distal occlusion balloons, filters, proximal protection systems and stent selection will be widely discussed.

Classification of prostatic diseases by means of multivariate analysis on in vivo proton MRSI and DCE-MRI data

Multivariate analysis has been applied on proton magnetic resonance spectroscopic imaging ((1)H-MRSI) and dynamic contrast enhanced MRI (DCE-MRI) data of patients with different prostatic diseases such as chronic inflammation, fibrosis and adenocarcinoma. Multivariate analysis offers a global view of the entire range of information coming from both the imaging and spectroscopic side of NMR technology, leading to an integrated picture of the system relying upon the entire metabolic and dynamic profile of the studied samples. In this study, we show how this approach, applied to (1)H-MRSI/DCE-MRI results, allows us to differentiate among the various prostatic diseases in a non-invasive way with a 100% accuracy. These findings suggest that multivariate analysis of (1)H-MRSI/DCE-MRI can significantly improve the diagnostic accuracy for these pathological entities. From a more theoretical point of view, the complementation of a single biomarker approach with an integrated picture of the entire metabolic and dynamic profile allows for a more realistic appreciation of pathological entities.

Diagnostic performance of 64-MDCT and 1.5-T MRI with high-resolution sequences in the T staging of gastric cancer: a comparative analysis with histopathology

PURPOSE

This study was undertaken to compare the accuracy of magnetic resonance (MR) imaging and 64-slice multidetector computed tomography (64-MDCT) in the T staging of gastric carcinoma in comparison with histopathology.

MATERIALS AND METHODS

Forty patients with an endoscopic diagnosis of gastric carcinoma underwent preoperative MR imaging and 64-MDCT, both of which were performed after i.v. injection of scopolamine and water distension of the stomach. In the MR imaging protocol, we acquired T2-weighted turbo spin-echo (TSE) sequences, true fast imaging steady-state free precession (true-FISP) and gadolinium-enhanced T1-weighted volumetric interpolated breath-hold examination (VIBE) 3D sequences. Contrastenhanced CT scans were obtained in the arterial and venous phases. Two groups of radiologists independently reviewed the MR and 64-MDCT images. The results were compared with pathology findings.

RESULTS

In the evaluation of T stage, 64-MDCT had 82.5% and MR imaging had 80% sensitivity. Accuracy of MR imaging was slightly higher than that of 64-MDCT in identifying T1 lesions (50% vs 37.5%), whereas the accuracy of 64-MDCT was higher in differentiating T2 lesions (81.2% vs 68.7%). The accuracy of MR imaging and 64-MDCT did not differ significantly in the evaluation of T3-T4 lesions (p>0.05). Understaging was observed in 20% of cases with MR imaging and in 17.5% with 64-MDCT.

CONCLUSIONS

MR imaging and 64-MDCT accuracy levels did not differ in advanced stages of disease, whereas MR imaging was superior in identifying early stages of gastric cancer and can be considered a valid alternative to MDCT in clinical practice.

Periprosthetic DXA after total hip arthroplasty with short vs. ultra-short custom-made femoral stems: 37 patients followed for 3 years

BACKGROUND AND PURPOSE

Dual-energy X-ray absorptiometry (DXA) analysis of the 7 periprosthetic Gruen zones is the most commonly used protocol to evaluate bone remodeling after the implantation of conventional femoral stems. We assessed the value of DXA after cementless primary total hip arthroplasty (THA) by comparing the effect of progressive shortening of the stem of two femoral implants on periprosthetic bone remodeling using a specifically developed protocol of analysis with 5 periprosthetic regions of interest (ROIs).

PATIENTS AND METHODS

Bone mineral density (BMD) was evaluated in 37 patients in the plateau stage, 3 years after THA. Two femoral implants featuring conceptually new designs and surgical technique were tested: types 1 and 2, characterized by extremely short stem and virtual absence of distal stem, respectively.

RESULTS

We found that progressive shortening of the femoral stem produces more proximal loading, which effectively preserves metaphyseal bone stock and increases periprosthetic BMD in the medial ROIs over time. In the type 2 group, higher absolute BMD values were observed in medial ROIs 4 and 5. No differences were found in ROIs 1, 2, and 3.

INTERPRETATION

This study shows the flexibility of DXA in adapting the protocol of periprosthetic analysis to the specific requirements of new implant designs, and it shows its high sensitivity in evaluation of the biological response of bone to changes in implant shape.

Is contrast-enhanced US alternative to spiral CT in the assessment of treatment outcome of radiofrequency ablation in hepatocellular carcinoma?

PURPOSE

The present study was conducted to assess the efficacy of contrast-enhanced ultrasound with low mechanical index in evaluating the response of percutaneous radiofrequency ablation treatment of hepatocellular carcinoma by comparing it with 4-row spiral computed tomography.

MATERIALS AND METHODS

100 consecutive patients (65 men and 35 women; age range: 62 - 76 years) with solitary hepatocellular carcinomas (mean lesion diameter: 3.7 cm +/- 1.1 cm SD) underwent internally cooled radiofrequency ablation. Therapeutic response was evaluated at one month after the treatment with triple-phasic contrast-enhanced spiral CT and low-mechanical index contrast-enhanced ultrasound following bolus injection of 2.4 ml of Sonovue (Bracco, Milan). 60 out of 100 patients were followed up for another 3 months. Contrast-enhanced sonographic studies were reviewed by two blinded radiologists in consensus. Sensitivity, specificity, NPV and PPV of contrast-enhanced ultrasound examination were determined.

RESULTS

After treatment, contrast-enhanced ultrasound identified persistent signal enhancement in 24 patients (24 %), whereas no intratumoral enhancement was detected in the remaining 76 patients (76 %). Using CT imaging as gold standard, the sensitivity, specificity, NPV, and PPV of contrast enhanced ultrasound were 92.3 % (95 % CI = 75.9 - 97.9 %), 100 % (95 % CI = 95.2 - 100 %), 97.4 % (95 % CI = 91.1 - 99.3 %), and 100 % (95 % CI = 86.2 - 100 %).

CONCLUSION

Contrast-enhanced ultrasound with low mechanical index using Sonovue is a feasible tool in evaluating the response of hepatocellular carcinoma to radiofrequency ablation. Accuracy is comparable to 4-row spiral CT.

Gadofosveset-enhanced MR angiography of carotid arteries: does steady-state imaging improve accuracy of first-pass imaging? Comparison with selective digital subtraction angiography

PURPOSE

To evaluate the diagnostic accuracy of gadofosveset-enhanced magnetic resonance (MR) angiography in the assessment of carotid artery stenosis, with digital subtraction angiography (DSA) as the reference standard, and to determine the value of reading first-pass, steady-state, and "combined" (first-pass plus steady-state) MR angiograms.

MATERIALS AND METHODS

This study was approved by the local ethics committee, and all subjects gave written informed consent. MR angiography and DSA were performed in 84 patients (56 men, 28 women; age range, 61-76 years) with carotid artery stenosis at Doppler ultrasonography. Three readers reviewed the first-pass, steady-state, and combined MR data sets, and one independent observer evaluated the DSA images to assess stenosis degree, plaque morphology and ulceration, stenosis length, and tandem lesions. Interobserver agreement regarding MR angiographic findings was analyzed by using intraclass correlation and Cohen kappa coefficients. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated by using the McNemar test to determine possible significant differences (P < .05).

RESULTS

Interobserver agreement regarding all MR angiogram readings was substantial. For grading stenosis, sensitivity, specificity, PPV, and NPV were, respectively, 90%, 92%, 91%, and 91% for first-pass imaging; 95% each for steady-state imaging; and 96%, 99%, 99%, and 97% for combined imaging. For evaluation of plaque morphology, respective values were 84%, 86%, 88%, and 82% for first-pass imaging; 98%, 97%, 98%, and 97% for steady-state imaging; and 98%, 100%, 100%, and 97% for combined imaging. Differences between the first-pass, steady-state, and combined image readings for assessment of stenosis degree and plaque morphology were significant (P < .001).

CONCLUSION

Gadofosveset-enhanced MR angiography is a promising technique for imaging carotid artery stenosis. Steady-state image reading is superior to first-pass image reading, but the combined reading protocol is more accurate.