Biomedical subjects

E Polettini

Publications and source records attributed to E Polettini.

At least 73 records · Page 4Linked to original sources

PubMed1993

[Current role of computerized tomography and prospectives of the use of magnetic resonance in the diagnosis of aortic abdominal aneurysms and evaluation of their complications].

In this work we discussed the role of conventional radiology, ultrasonography (US), angiographic study, CT scan and MR imaging in the diagnosis of abdominal aortic aneurysms and their complications. US is the most suitable technique for screening and follow-up study of aortic aneurysms. Unfortunately it is not so reliable in the study of visceral arteries and in fat patients. Aortic angiography is the most useful method for the study of visceral arterial branches, but it does not show the phlogistic changes as well as the peripheral thrombotic alterations within the lesion. TC scan is also a useful technique in the study of aortic aneurysm, although it is not so accurate in detecting the visceral arterial branches. Finally, we think that MR imaging is the most reliable method for the diagnosis of aortic aneurysm. Movement artifact and lack of information due to the poor visualization of calcifications are still the principal limits of this technique.

Aortic Aneurysm, Abdominal↗

PubMed1993

[Diagnostic imaging in the evaluation of masses developing in the cerebral ventricles].

CT scan and MR imaging of intraventricular masses are discussed in this work. The lesions affecting this region may be of neoplastic, vascular or phlogistic origin. CT scan and MR imaging are useful for diagnosis and management of these lesions. Intraventricular masses are well documented by high resolution CT scan after administration of endo-rachideal metrizamide, during ventriculographic studies. This technique gives important informations about peripheral relationship of intraventricular masses with increased liquoral fluid. MR imaging is also available for characterizing pathologic tissues, and for detecting the anatomic relationships between pathologic and normal structures.

Astrocytoma↗

PubMed1993

[Comparison of magnetic resonance and other imaging methods in the diagnosis of diseases of the seminal vesicles].

The aim of this work was to evaluate the usefulness of MR imaging in the diagnostic study of seminal vesicles and to emphasize the relationships between this technique, CT scan and trans-rectal ultrasonography (TR-US). We discussed pathological findings due to congenital anomalies, phlogistic or neoplastic lesions and iatrogenic changes of normal tissues. MR imaging and TR-US seem to be the most reliable techniques for typing pathological tissues and for grading the extension of neoplatic masses arising from bladder, prostate, and rectum, involving seminal vesicles.

Diagnostic Imaging↗

PubMed1993

[Aortic dissection: the role of diagnostic imaging, with special reference to magnetic resonance imaging and its implications in the pathogenesis].

The aim of this work was to evaluate the usefulness of angiography, CT scan and MR imaging in the diagnosis of aortic dissection, on the basis of the authors' experience and literature review. Angiographic study is still considered the first choice technique in the diagnosis of aortic dissection, although it is considered not completely safe. CT scan allows to note the early thickening of the vessel walls (due to intraparietal bleeding) and the presence of calcifications in the thrombosed portion of the lesion. MR study allows multiplanar study of the lesions without contrast medium, and best visualization of subendothelial bleeding in dissections without intimal lesion.

Aortic Dissection↗

PubMed1992

Computed tomography for preoperative assessment of T3 and T4 bronchogenic carcinoma.

Between January 1986 and January 1991, 175 patients with suspected T3 or T4 bronchogenic carcinoma underwent computed tomographic (CT) examination of the chest before thoracotomy. We considered two groups of patients: group 1 includes 98 patients with a paramediastinal mass on standard chest X-ray; invasion of hilar and mediastinal structures was preoperatively investigated with CT and then assessed at thoracotomy. The sensitivity, specificity and accuracy were 72%, 75% and 73%, respectively; positive and negative predictive values were 71% and 76%. In group 2 77 patients had a peripheral tumor suspected of invading the parietal pleura and the soft tissues of the chest wall (patients with evident rib or vertebral invasion were not included). Sensitivity, specificity and accuracy of CT were 52%, 86% and 71%, respectively; positive and negative predictive values were 74% and 70%. We conclude that CT with injection of contrast material is indispensable when direct lung cancer infiltration must be ruled out; its accuracy is however not sufficient to be relied upon in all patients.

Adult↗

PubMed1992

[A comparison between computed tomography and magnetic resonance in the verification of prolactinomas].

First, computer tomography and subsequently magnetic resonance have profoundly changed the diagnostic protocol for the study pituitary pathology. Conventional X-ray and examination with the use of contrast media are being employed less and less. Tomographic techniques (CT and RM) permit direct identification of anomalies as well as precise evaluation of their relationship with surrounding structures.

Contrast Media↗

PubMed1992

[Role of magnetic resonance in the evaluation of thrombosis of large thoraco-abdominal vessels].

Magnetic resonance (MR) has been found to be a method suitable for the study of the vascular system since it permits to distinguish between moving (circulating blood) and static (thrombi, atherosclerotic plaques, intimal flaps) tissues. The sequences used for the evaluation of thrombi are Spin Echo (SE) and Gradient Echo (GE). If both sequences are used the diagnosis of thrombosis is considerably more reliable. The limits of the technique are represented by spatial resolution which is not optimal and makes the evaluation of thrombi in small or medium-size vessels difficult; further, small or non occlusive thrombi may be difficult to identify. Nowadays, with the technique of angiography with magnetic resonance (AMR) it has become possible to obtain high quality images of the vessels of the head, neck, abdomen and limbs. Further improvements of the AMR technique are likely to replace diagnostic angiography.

Abdomen↗

PubMed1992

[A comparison between intraurethral echography, computed tomography and magnetic resonance in the staging of bladder tumors].

The purpose of our study was to assess the utility of CT and MRI in the staging of bladder carcinoma. The overall accuracy of MR is in the range of 66 to 85%. T2 weighted and post-Gadolinium T1 weighted images allow one to differentiate T1-T2 from T3a type of neoplasms. Perivesical fat invasion is well shown with T1w images while pelvic wall invasion is better seen on T2w--images. The overall accuracy of CT ranges from 64 to 92%. CT cannot distinguish stage T1 from stage T3a tumors CT is accurate for demonstrating perivesical fat invasion. In the assessment of lymph node metastases CT and MRI have low sensitivity but high accuracy. Trans-urethral sonography is more accurate than CT and MRI in the staging of parietal invasion and it permits the differentiation between T1, T2 and T3a stages even though the distinction between T2 and T3a type of tumors is not always possible. Trans-urethral sonography is not useful in assessing extravesical extension and lymph node metastases. In summary, trans-urethral sonography is the method of choice for evaluating parietal invasion. CT and MR are very accurate for evaluating perivesical fat invasion and are also quite accurate for evaluating lymph nodes. MRI is superior to CT in distinguishing tumors limited to superficial muscle from those that invade deep muscle. MRI can also be helpful in distinguishing the tumor from fibrosis and edema.

Diagnosis, Differential↗

PubMed1992

[Computed tomography and magnetic resonance in the TNM staging of pulmonary carcinoma].

On the basis of a review of the literature and of the authors' personal experience, the usefulness was evaluated of CT and MR for the staging of lung carcinoma. Neither method was found to be useful for diagnosis; as to staging, neither is capable to distinguish between simple adhesion and infiltration of adjacent structures by the tumor. As compared to CT, MR has the advantage of showing many layers and better contrast resolution but spatial resolution is poorer. MR was superior to CT for the study of hilar lesions (easily differentiated from vessels) and for those involving the upper pulmonary sulcus. The accuracy of evaluation of the N parameter was the same for both methods whereas for the M parameter RM was more accurate than CT. Considering the wide margins for technological improvement of MR, a more important role for this method compared to CT can be hypothesized.

Carcinoma↗

PubMed1990

[MR in rectal cancer recurrences].

Fourteen patients, who had undergone surgery for rectal carcinoma, were studied by MR imaging to evaluate the presence of recurrences. MR results were compared to those obtained by needle biopsy or laparotomy. MR imaging proved to be a valuable method in diagnosing tumor recurrences on the basis of tissular morphology, whereas its capabilities were poor in differentiating recurrence from fibrosis on the basis of the signal intensity on T2-weighted images.

Biopsy↗

PubMed1990

[The role of magnetic resonance in the study of cerebrospinal malformations in childhood. An analysis of 51 clinical cases].

This study was aimed at assessing MR utility in the evaluation of cerebral-medullar malformative pathologic conditions in infants. Among 274 patients 2 months to 15 years old examined by means of MR imaging, 51 (18.6%) were affected with cerebral-medullar abnormalities. Seventeen different types of pathologic conditions were identified, some of which single and some multiple; tethered cord was the most frequent finding. 45/51 patients affected with malformative pathologic conditions required sedation. The high incidence of malformative pathologic conditions in pediatrics highlights the importance of this subject for all the radiologists dealing with MR imaging in pediatrics. MR imaging appears to be the method of choice for the evaluation of cerebral-medullar abnormalities.

Abnormalities, Multiple↗

PubMed1989

[MR in the evaluation of schizencephaly].

This study was aimed at evaluating MR utility in the diagnosis of schizencephaly in patients with seizures and developmental delay. In 7 patients, 8 months to 15 years old, MR imaging detected the presence of unilateral (5 cases) and bilateral (2 cases) hemisferic clefts. Moreover, MR imaging allowed the presence of such anomalies as dysgenesis of the corpus callosum, and agenesis of the septum pellucidum to be demonstrated, together with areas of polymicrogyria and heterotopic gray matter.

Adolescent↗

PubMed1989

[CT in the evaluation of carcinoma of the pancreas].

The routine use of CT has given a great contribution both to the diagnosis and to the evaluation of the extent of pancreatic carcinomas. Forty-three patients clinically suspected of pancreatic carcinoma were examined with CT. Forty of them underwent surgical control. This study was conducted to evaluate the role of CT in the diagnosing and staging of pancreatic carcinomas. 31/43 neoplasms were identified, with a diagnostic accuracy of 90%. CT was extremely accurate in the demonstration of late metastases, while it had lower accuracy in assessing the involvement of lymph nodes and peripancreatic vessels (60-70%). CT proved to be extremely useful in diagnosing pancreatic carcinomas, for it allows the detection of masses associated with Wirsung's duct dilatation and atrophy, which are a highly pathognomonic sign of pancreatic neoplasms. Moreover, CT proved useful in the staging, by assessing the presence of lymph nodes and metastases.

Aged↗

PubMed1988