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Simona Gaudino

Publications and source records attributed to Simona Gaudino.

11 recordsLinked to original sources

Contrast-enhanced MR imaging of the spine: when, why and how? How to optimize contrast protocols in MR imaging of the spine.

The optimal protocols and the role of contrast agents in spinal MR imaging are controversial. Although the diagnosis of many common spinal diseases can be reliably achieved by means of unenhanced images, contrast use is often necessary to improve lesion detection and differential diagnosis. The heterogeneity of the different spinal compartments and the wide variety of spinal pathology require tailored imaging strategies. Thus, the rules to achieve optimization of contrast protocols for MR imaging of the spine are frequently very different to those for brain imaging, and depend on the location and site of origin of the lesions in a specific spinal compartment, on the findings of unenhanced imaging, and on the concomitant use of fat-suppression techniques. Furthermore, in most cases, the small size of the examined structures requires a meticulous technique, and the administration of a contrast agent with high relaxivity, such as MultiHance, is advisable to enable the detection of tiny areas of contrast enhancement. The applications and clinical utility of post-contrast MR imaging are discussed with regard to different spinal diseases.

Contrast Media↗

Simultaneous cardiac and respiratory synchronization in oxygen-enhanced magnetic resonance imaging of the lung using a pneumotachograph for respiratory monitoring.

OBJECTIVES: We sought to evaluate an optimized method for oxygen-enhanced magnetic resonance imaging of the lung, using electrocardiogram-trigger and a pneumotachograph for simultaneous cardiac and respiratory synchronization. MATERIALS AND METHODS: Five series of IR-SSFSE images (echo time = 28.2 milliseconds; inversion time = 1,200 milliseconds) were obtained in 6 volunteers during the ventilation-paradigm room-air/oxygen/room-air: series 1, respiratory-triggered; series 2, cardiac-triggered; series 3, cardiac-triggered and respiratory-synchronized using the signal of the pneumatic belt; series 4, cardiac-triggered and respiratory-synchronized using the external signal of the pneumotachograph; and series 5, not cardiac-triggered and respiratory-synchronized using the signal of the pneumotachograph. Standard deviations of the lung (SI(var)) and diaphragm mismatch (DM) were measured. The relative SI change (DeltaSI) was computed from room-air and oxygen-enhanced images. Parametric maps were obtained from cross-correlation analysis of the ventilation paradigm. Mean correlation coefficients (cc) and the percentage of activated pixels over the lung (Act%) were calculated from these maps. All 5 parameters were compared among the 5 series (Friedman-analysis of variance, Dunn's posthoc test). RESULTS: In series 4, DM and SI(var) were significantly lower than in respiratory and cardiac-triggered series (DM = 4.7 vs. 14.3 and 18.4; SI(var) = 4.9 vs. 10 and 11). In the same series cc and Act% also were significantly higher than in series 1 and 2 (cc = 0.86 vs. 0.7 and 0.6; Act% = 71.3 vs. 44.7 and 41.2). DeltaSI was not significantly different among all series. CONCLUSIONS: Effective respiratory and cardiac synchronization can be achieved in oxygen-enhanced magnetic resonance imaging of the lung, using a pneumotachograph for real-time targeting of end-expiration.

Adult↗

Immunohistochemical-scintigraphic correlation of sympathetic cardiac innervation in postischemic left ventricular aneurysms.

BACKGROUND: This study was conceived to explore the correspondence between scintigraphic imaging of the sympathetic innervation of human postischemic left ventricular aneurysms and direct immunohistochemical localization of the nerve fibers in the same area. MATERIALS AND METHODS: In 7 patients undergoing left ventricular aneurysmectomy for postischemic ventricular aneurysm, the findings of thallium 201 and metaiodobenzylguanidine myocardial scintigraphy were compared with direct immunohistochemical localization of the nerve fibers in the same area. This comparison showed good correspondence between scintigraphic and immunohistochemical data, although scintigraphy failed to detect areas of minimal sympathetic innervation. Moreover, microscopic analysis showed sympathetic nerve fibers with peculiar morphology and distribution in the aneurysmal zone. CONCLUSION: There is a good correspondence between immunohistochemical and scintigraphic imaging in the detection of sympathetic cardiac nerves in human left ventricular aneurysms; a morphologically abnormal sympathetic reinnervation can be found in the aneurysmal area (although denervation can persist in some zones).

3-Iodobenzylguanidine↗

Diffusion and perfusion MR imaging.

Diffusion (DWI) and perfusion weighted (PWI) MR imaging, have come to have an increasingly important clinical role, especially in neurovascular imaging. Diffusion MR imaging does not evaluate hemodynamic parameters, but can be considered a functional technique because it provides information about the tissue functional structure at a microscopic level. In this technique, image contrast to a large extent depends on the diffusion coefficient, a parameter indicative of the characteristics of the stochastic thermic translational motion of water molecules (Brownian motion). Clinical perfusion measurement has been performed in almost all organs with different techniques. Over the last ten years, with the use of contrast media, considerable experience has been gained in the measurement of hemodynamics with MRI. At present, perfusion-MR imaging is one of the clinically most relevant procedures of functional MRI, whose application is gaining ground, owing to the increasing availability of necessary hardware and software. Physical and hemodynamic principles of the two techniques, pulse sequences necessary for their implementation and main applications in the imaging of CNS disorders are illustrated. While DWI and PWI alone can address numerous questions, their information is for the most part complementary to that provided by conventional MRI and their combination seems extremely promising.

Central Nervous System Diseases↗

Combined diagnostic and therapeutic imaging in the diagnosis of venous sinus thrombosis in postpartum patients.

The case of a woman on day four post partum with sensorimotor deficit of the right side and CT evidence of a left temporofrontal hemorrhagic lesion, is presented. Attending physicians requested cerebral angiography. To better evaluate the clinical justification of requested imaging procedure the patient medical history and performed CT examination were carefully revised. According to this analysis and based on a clinicoradiological methodology, the request of a cerebral angiography was considered appropriate. The examination showed several radiological signs but a definitive diagnosis could not be established. Second choice imaging procedures were analyzed and MRI completed with MR-angiography was performed. It allowed to document transverse and sigmoid sinus thrombosis. Therefore, in the diagnosis of venous sinus thrombosis, MRI combined with MR-angiography was shown to be a method of first choice while angiography plays a major role in therapy for intravascular thrombolysis.

Adult↗

Conventional MRI, DWI and MR-spectroscopy in the study of focal brain lesions.

A case of a patient with neurologic symptoms is reported. Baseline MRI findings were inconclusive to establish a definitive diagnosis. The worsened neurologic and neuroradiologic pattern directed towards a diagnosis of tumor. A second MRI examination and MR-spectroscopy confirmed the hypothesis based on both the diagnosis of nature of the lesion and the histological characterization of the surgical specimen. The technique of MR-spectroscopy is briefly described.

Aged↗

Combined diagnostic imaging of a male breast lesion.

The case of a male patient with gynecomastia of the left mammary gland is discussed. The differential diagnosis was considered in relation to other possible benign and malignant lesions where there is swelling of the mammary gland in men. US was the examination of first choice. To complete the study of the diagnostic pattern, mammography was also performed. The definitive diagnosis was true nodular gynecomastia caused by chronic liver disease.

Chronic Disease↗

A case of mammotome biopsy: retrospective evaluation.

The case of a female patient with a normal mammography of first level screening and a control mammography showing the presence of a cluster of microcalcifications, is discussed. The case history is carefully examined also based on previous investigations. The patient decided to undergo stereotactic vacuum-assisted biopsy (mammotome biopsy) that was performed elsewhere. Indications, advantages and possible complications of the procedure are analyzed.

Biopsy↗

Combined diagnostic imaging and management of a breast tumor in a young woman.

The typical presentation of breast cancer in a young woman is discussed. Diagnostic imaging of the breast showed the presence of an extensive pathological area, approximately 5 cm in size, at the level of the upper quadrants of left breast. On mammography the pathological sign was represented by numerous regional granular microcalcifications. On sonography an inhomogeneously hypoechoic area with intralesional hyperechoic spots was identified. On MRI a large area of pathological enhancement was visualized. For the tumor extent and the patient's young age neoadjuvant chemotherapy was performed. Post-treatment assessment showed good response to therapy, suggestive of possible better prognosis.

Adult↗

A case of intracystic breast cancer.

The case of a 70-year-old female patient with family history of breast cancer come to the breast Unit for the presence of a nodular swelling in the right breast is discussed. On mammography and US a gross cystic neoformation with vascularized mural nodes was identified. Another contralateral solid nodular neoformation suggestive of malignancy was also present. Diagnostic completion with MRI confirmed the mixed solid, partly cystic nature of the right lesion, leading to the differential diagnosis with cystosarcoma phylloides and intracystic tumor. On the left side, MRI confirmed the presence of the second lesion whose morphologic and dynamic characteristics suggested a neoplastic lesion. At the anatomopathological examination the left lesion was shown to be an infiltrating ductal carcinoma; the right lesion was shown to be an intracystic tumor.

Aged↗