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Lorenzo Bonomo

Publications and source records attributed to Lorenzo Bonomo.

33 records · Page 2Linked to original sources
PubMed2003

Functional topography of the secondary somatosensory cortex for nonpainful and painful stimuli: an fMRI study.

The regional activity of the contralateral primary (SI) and the bilateral secondary (SII) somatosensory areas during median nerve stimulations at five intensity levels (ranging from nonpainful motor threshold to moderate pain) was studied by means of functional magnetic resonance imaging (fMRI). The aim was to characterize the functional topography of SII compared to SI as a function of the stimulus intensity. Results showed that the galvanic stimulation of the median nerve activated the contralateral SI at all stimulus intensities. When considered as a single region, SII was more strongly activated in the contralateral than in the ipsilateral hemisphere. When a finer spatial analysis of the SII responses was performed, the activity for the painful stimulation was localized more posteriorly compared to that for the nonpainful stimulation. This is the first report on such a SII segregation for transient galvanic stimulations. The activity (relative signal intensity) of this posterior area increased with the increase of the stimulus intensity. These results suggest a spatial segregation of the neural populations that process signals conveyed by dorsal column-medial lemniscus (nonpainful signals) and neospinothalamic (painful signals) pathways. Further fMRI experiments should evaluate the functional properties of these two SII subregions during tasks involving sensorimotor integration, learning, and memory demands.

Adult↗
PubMed2003

Gadobenate dimeglumine-enhanced magnetic resonance angiography of the pelvic arteries.

RATIONALE AND OBJECTIVES: To evaluate 4 doses of gadobenate dimeglumine (Gd-BOPTA) for contrast-enhanced magnetic resonance angiography (CE-MRA) of the pelvic arteries and to compare CE-MRA with unenhanced time-of-flight MRA (2D-TOF-MRA). METHODS: A multicenter Phase II dose-finding study was performed in 136 patients with Gd-BOPTA doses of 0.025, 0.05, 0.1, and 0.2 mmol/kg bodyweight. Evaluation of CE-MRA images and comparison with 2D-TOF-MRA images was performed onsite and by 2 blinded offsite reviewers in terms of subjective image quality, number of lesions detected, and confidence in lesion characterization. RESULTS: Significant (P < 0.05) improvements over unenhanced findings were observed for CE-MRA at all dose levels. For reviewer 1 and the onsite investigators, the overall image quality increased up to a dose of 0.1 mmol/kg and then plateaued. For reviewer 2, increased image quality was noted up to a dose of 0.2 mmol/kg. Significant (P < 0.005) increases in diagnostic confidence on CE-MRA versus unenhanced MRA was observed for all dose groups by reviewer 1 and the onsite investigators and for the 0.1 and 0.2 mmol/kg dose groups by reviewer 2. No serious adverse events were recorded that were attributable to the study drug and no trends in laboratory parameters, vital signs, or electrocardiogram recordings were observed. CONCLUSIONS: Gadobenate dimeglumine-enhanced MRA is safe and significantly more effective than unenhanced 2D-TOF-MRA for imaging the pelvic arteries. A dose of 0.1 mmol/kg appears the most appropriate dose for subsequent Phase III clinical evaluation.

Adolescent↗
PubMed2003

Gadobenate dimeglumine-enhanced MRI of the breast: analysis of dose response and comparison with gadopentetate dimeglumine.

OBJECTIVE: The purpose of this study was to evaluate the clinical efficacy and dose response relationship of three doses of gadobenate dimeglumine for MRI of the breast and to compare the results with those obtained after a dose of 0.1 mmol/kg of body weight of gadopentetate dimeglumine. SUBJECTS AND METHODS. Gadobenate dimeglumine at 0.05, 0.1, or 0.2 mmol/kg of body weight or gadopentetate dimeglumine at 0.1 mmol/kg of body weight was administered by IV bolus injection to 189 patients with known or suspected breast cancer. Coronal three-dimensional T1-weighted gradient-echo images were acquired before and at 0, 2, 4, 6, and 8 min after the administration of the dose. Images were evaluated for lesion presence, location, size, morphology, enhancement pattern, conspicuity, and type. Lesion signal intensity-time curves were acquired, and lesion matching with on-site final diagnosis was performed. A determination of global lesion detection from unenhanced to contrast-enhanced and combined images was performed, and evaluations were made of the diagnostic accuracy for lesion detection and characterization. A full safety evaluation was conducted. RESULTS: Significant dose-related increases in global lesion detection were noted for patients who received gadobenate dimeglumine (p < 0.04, all evaluations). The sensitivity for detection was comparable for 0.1 and 0.2 mmol/kg of gadobenate dimeglumine, and specificity was highest with the 0.1 mmol/kg dose. Higher detection scores and higher sensitivity values for lesion characterization were found for 0.1 mmol/kg of gadobenate dimeglumine compared with 0.1 mmol/kg of gadopentetate dimeglumine, although more variable specificity values were obtained. No differences in safety were observed, and no serious adverse events were reported. CONCLUSION: Gadobenate dimeglumine is a capable diagnostic agent for MRI of the breast. Although preliminary, our results suggest that 0.1 mmol/kg of gadobenate dimeglumine may offer advantages over doses of 0.05 and 0.2 mmol/kg of gadobenate dimeglumine and 0.1 mmol/kg of gadopentetate dimeglumine for breast lesion detection and characterization.

Adult↗
PubMed2003

Spiral CT-angiography with one, four, and sixteen slice scanners. Technical note.

Aim of this paper is to describe the technical main features that characterize Spiral Computed Tomography (CT) angiography. In particular, the technical features of the three main generations of single, four, and sixteen multislice scanners have been analised. Particular attention have been addressed to scan and reconstruction parameters, and to the geometry of contrast material related to angiographic scan. Guidelines for the different generations of CT scanner have been extracted to give the radiologist a platform for diagnostic questions.

Angiography↗
PubMed2002

Non-traumatic thoracic emergencies: acute chest pain: diagnostic strategies.

Acute chest pain may represent the initial and/or accompanying symptom in a variety of disease processes that may occur in the cardiovascular system, respiratory system, gastrointestinal tract, or musculoskeletal system. Although clinical history, risk factors, and physical examination are important factors in establishing the etiology of symptoms in patients presenting with acute chest pain, imaging modalities are frequently utilized. Noncardiac causes of acute chest pain are reviewed in this paper with special reference to the most recently published literature and emphasis on acute aortic diseases. Imaging modalities with indication of appropriateness, optimal technique and practical keys for interpretation are discussed.

Acute Disease↗
PubMed2002

Contrast-enhanced magnetic resonance angiography MoBI-trak in the study of peripheral vascular disease.

PURPOSE: To evaluate the diagnostic accuracy of contrast-enhanced magnetic resonance angiography (CE-MRA) MoBI-trak of peripheral vessels in patients with peripheral vascular disease who were candidates for digital subtraction angiography (DSA). METHODS: Eleven patients underwent CE-MRA with automated table movement (MoBI-trak) using a 1.5 T superconducting magnet (Philips Gyroscan ACS NT) equipped with a Power Trak 6000 gradient. Contrast medium (Gd-DTPA) was administered in two sequential boluses-20 cm(3) at 0.6 cm(3)/sec (starting phase) and 20 cm(3) at 0.3 cm(3)/sec (maintenance phase)-using a MedRad Spectris automatic injector. DSA was the gold standard and was performed using a Philips Integris 3000, with a brilliance intensifier of 38 seconds. DSA and MRA were evaluated on printed films. RESULTS: DSA provided 213 diagnostic assessments: 144 negative, 30 stenosis <50%, 5 stenoses in the 51-70% range, 12 stenoses in the 71-99% range and 22 occlusions. CE-MRA MoBI-trak sensitivity, specificity, positive and negative predictive value and diagnostic accuracy were 94.1%, 99.2%, 98.4%, 80.0% and 97.5%, respectively. CONCLUSIONS: Our work is in accordance with the literature. Using this technique MoBI-trak has been shown to be a reliable technique for the detection of peripheral vascular disease up to the trifurcation, although it underlines the necessity for more diagnostic investigation and improvements in the technique.

Angiography, Digital Subtraction↗
PubMed2002

Gadobenate dimeglumine-enhanced MR angiography of the abdominal aorta and renal arteries.

OBJECTIVE: This study was conducted to determine the efficacy and safety of four different doses of gadobenate dimeglumine for contrast-enhanced three-dimensional MR angiography of the abdominal aorta and renal arteries. SUBJECTS AND METHODS: Ninety-four patients with suspected abnormality of the abdominal aorta or renal arteries underwent unenhanced three-dimensional gradient-recalled echo time-of-flight MR angiography and contrast-enhanced MR angiography after the IV injection of one of four doses of gadobenate dimeglumine (0.025, 0.05, 0.1, and 0.2 mmol/kg of body weight). Efficacy was assessed on-site and by two blinded off-site reviewers in terms of change in total diagnostic quality score and diagnostic quality score per vessel segment from baseline unenhanced time-of-flight MR angiography to contrast-enhanced MR angiography. Secondary efficacy end points included lesion count and level of confidence in lesion characterization. Safety assessments comprised adverse event monitoring, physical evaluation, vital signs, ECG, and laboratory investigations. RESULTS: A significant change in the total diagnostic quality score from unenhanced to contrast-enhanced MR angiography was observed at all doses. The change increased with increased dose, plateauing at the 0.1 mmol/kg dose level. More patients with lesions detected and increased reviewer confidence for lesion characterization were noted on contrast-enhanced MR angiography compared with unenhanced MR angiography, although no dose-related trends were observed. All doses were well tolerated, and no significant changes in safety parameters were observed. CONCLUSION: Gadobenate dimeglumine is an effective and safe agent for contrast-enhanced MR angiography of the abdominal aorta and renal arteries. A dose of 0.1 mmol/kg of body weight appears to be the most suitable.

Adult↗
PubMedDate not supplied

Extravascular incidental findings at multislice CT angiography of the abdominal aorta and lower extremity arteries: a retrospective review study.

PURPOSE: To assess the frequency and clinical impact of extravascular incidental findings on routine CT angiography of abdominal aorta or lower extremity arteries. MATERIALS AND METHODS: From January 2002 to July 2004, a total of 692 patients underwent CT angiography of abdominal aorta and lower extremity arteries. Two radiologists retrospectively reviewed by consensus cross-sectional images for the presence and clinical impact definition of extravascular findings. The revision of hospital charts, medical records, and all procedures' reports performed before and after CT angiography represented the standard of reference (SOR). RESULTS: Only 373 out of 605 patients in whom extravascular findings were found had a SOR; in these patients CT angiography obtained a true-positive incidental rate of 98.9% (369/373). For the clinical impact definition of CT-angiography incidental findings, a concordance with SOR was obtained in 56.3% of patients, whereas a subsequent investigation was required in 183 patients (183/369, 49.6%). Among clinically relevant incidental findings, a total of 35 malignancies (35/894, 3.9%) were detected in 20 patients (20/423, 4.7%); in 15 patients (15/423, 3.5%) malignancy was unknown before CT-angiography exam. CONCLUSIONS: A careful observation of cross-sectional images, even if "time consuming", is mandatory not only to assess vascular findings but also to avoid a misdiagnosis of clinical relevant extravascular findings.

Aged↗
PubMedDate not supplied

Primary renal angiosarcoma: a rare malignancy. A case report and review of the literature.

Angiosarcoma is a rare malignant tumor occurring in less than 2% of soft tissue sarcomas. Angiosarcoma involving the kidney usually represents metastasis from skin or visceral primary lesions, while angiosarcoma primarily occurring in the kidney is a very rare neoplasm. In the English literature, from 1942 to the present, only 19 cases of primary kidney angiosarcoma have been reported. A case of primary renal angiosarcoma presenting as a large kidney mass and flank pain occurring after traumatism is reported. The present case represents further evidence of a rare malignancy.

Hemangiosarcoma↗
PubMedDate not supplied

Color-Doppler sonography in chronic venous insufficiency: what the radiologist should know.

Chronic venous insufficiency (CVI) is a pathologic condition caused by valvular incompetence, with or without associated venous outflow obstruction, which may affect both the superficial and the deep venous system, causing venous hypertension and stasis. The most common form of CVI is primary varicose veins due to the insufficiency of the saphenous system. Color-Doppler sonography (CDS) is actually the main diagnostic technique of imaging for CVI. In this article, we describe the anatomy, the technique, and the information necessary to the radiologist to perform CDS in chronic venous insufficiency. The knowledge of the venous anatomy is the cornerstone for an adequate sonographic examination. The venous network in the lower extremities is divided into three systems: superficial, deep, and perforating veins. Deep veins are "comitantes" to the corresponding arteries and run under the muscular fascia. Superficial veins course into the subcutaneous fat, superficially to the deep muscular fascia; the main superficial veins are the greater and lesser saphenous and their tributaries. Connection between the saphenous veins are defined as communicating veins. Superficial and deep veins are connected by perforating veins, with flow directed, under normal circumstances, from the superficial to the deep system. The main perforating are the Hunter in the mid thigh, the Dodd in the lower thigh, the Boyd in the upper calf, and the Cockett's in the middle and lower calf. Sonographic examination must be performed in the upright and supine position. Compression sonography and color and PW Doppler are systematically employed to assess the absence of deep venous thrombosis. Femoro-popliteal veins are evaluated with color and PW Doppler for valvular insufficiency with reflux by performing Valsalva maneuver and calf compression. The sapheno-femoral and sapheno-popliteal junctions are examined to identify type of junction, continence, accessory saphenous, and incompetent collaterals. Perforating veins are usually identified at the medial aspect of the thigh and at the medial, lateral, and posterior aspects of the leg. Outward flow (lasting more than 500 ms) in the perforating veins should be considered a sign of their incompetence. Several surgical and interventional procedures are now available for the treatment of the CVI, as follows: vein ligation and stripping, stab avulsion, endoluminal occlusion of the saphenous trunks, subfascial endoscopic perforator surgery, and valvuloplasty.

Angioplasty↗
PubMedDate not supplied

[Normal anatomy of the vessels of the heart with 16-row multislice computed tomography].

Nowadays, cardiac imaging is not part of the clinical routine for the radiologist. Multislice Computed Tomography (MSCT) with 4 rows allowed to start the non invasive evaluation of coronary arteries. The introduction of 16-row MSCT has significantly improved the performance and diagnostic accuracy of this technique, so far that MSCT angiography has been advocated as a potential clinical tool for the study of coronary artery disease. Therefore, it is mandatory to understand normal cardiac and coronary anatomy in order to evaluate the presence and severity of coronary artery disease. The anatomical visualisation provided by MSCT differs from the one of conventional coronary angiography because it is not a simple "lumenology" but it is capable to provide information on the vessel wall, until now only achieved by invasive techniques such as intravascular ultrasound or optical coherence tomography, and on neighbouring structures. Aim of this works is to provide the basics of anatomy of the vessels of the heart applied to MSCT.

Coronary Angiography↗