Diffusion-weighted MRI in patients with non-diagnostic CT in the post-acute phase of cerebral ischemia.

BACKGROUND: Unenhanced computed tomography (CT) is the imaging technique used in acute stroke. In some cases it is unable to detect damage even 24-48 h after symptom onset. The aim of our work was to evaluate the diagnostic value of diffusion-weighted imaging (DWI) in the post-acute phase of cerebral ischemia in patients in whom CT did not yield a definitive diagnosis. METHODS: We retrospectively evaluated DWI findings in 214 patients, out of a series of 1,680 patients admitted to our hospital following the acute onset of focal neurological symptoms, in whom non-contrast CT, performed within 30 h of symptom onset, was normal (123), incongruous, i.e. a marked hypodensity indicative of an old infarct or a slight hypodensity not consistent with the clinical findings (66), or leukoaraiotic, i.e. diffuse chronic hypodensities in the periventricular white matter (25). RESULTS: DWI showed signs of recent brain ischemia in 125/214 (58%) patients: 64/123 (52%) with a normal CT, 41/66 (62%) with an incongruous CT, and 20/25 (80%) with leukoaraiosis (p=0.027). Multiple lesions were detected in 16/125 (16%) patients, while single lesions were

[16-MDCT angiography coronary artery in the emergency department for patients with acute coronary syndrome (NSTEMI-UA)]. / La 16-MDCT delle arterie coronarie eseguita in urgenza nei pazienti affetti da sindrome coronarica acuta (NSTEMI-UA).

AIM: The diagnosis of acute coronary syndrome (ACS), non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) remains a challenge. The aim of our study was to investigate quality and the diagnostic accuracy of 16-MDCT coronary angiography, detecting coronary artery lesions in patients with suspected ACS presented in ED. MATERIALS AND METHODS: We studied with 16-MDCT (Sensation 16, Siemens, Forchleim, Germania) and coronary angiography 37 patients with the following inclusion criteria: chest pain compatible with myocardial ischemia, normal or no-diagnostic ECG changes and initial concentrations of serum troponin-I < or =1 ng/ml. The 16-MDCT was performed with ECG-gated technique after the intravenous administration of 90-100 ml of iodinated contrast material followed by a saline bolus. The scan parameters were: 120 kV, 650-720 mAs, 16 x 0.75mm collimation, 0.42s rotation time, 3 mm (pitch 0.25) feed/rot, B30f kernel. We evaluated for each patient: image quality and different artefacts, plaques identification and characterization. RESULTS: The evaluation of the image quality was based on a total of 453 segments, of which 415 segments (92.2%) were considered to have diagnostic image quality. MDCT correctly detected 15 patients with at least 1 stenosis >50% and correctly ruled out significant coronary artery disease in 19 patients with 1 FP and 2 FN: sensitivity 88%, specificity 95%, PPV 94%, NPV 90%. The plaques were hard in 6 cases, mixt in 16 cases and soft in 14 cases, respectively. CONCLUSIONS: Our results point-out that 16-MDCT in ED has the real ability to detect and rule out significant coronary stenoses in patients with ACS.

[The radiation dose problem in computed tomography. Actual data and strategies for a corrected use of ionizing radiation in computed tomography]. / Il problema della dose di radiazioni in tomografia compute- rizzata. dati attuali e strategie per un corretto utilizzo delle radiazioni ionizzanti in tomografia computerizzata.

New technologies in these years has taken to a spread and to a growth of the CT application with an increase of patients and population exposure. In clinical practice some technical devices can be used to reduce the exposure dose of multidetector CT that allows radiologist to answer the clinical question with less damage to the patient. The radiologist remains however the guarantor of the ionizing radiation exposition and he has to consider also the opportunity to use other methodics (MR, US) to answer some questions. The radiologist has the role to evaluate the clinical indication to the exam demanded from other doctor and has the responsibility for exam management and for progressive radiologic course, controls and follow-up.

[Child abuse: imaging of multiorgan damages]. / Il bambino maltrattato: imaging dei danni multiorgano.

An abused child can present with every lesion known to medicine, but some of these lesions can be specific of child abuse. The most frequent skeletal lesions are that of the long bones, of the head and the chest. Head damages are responsible for 80% of the dead in abused child. These kind of lesions are very important because they can produce important neurological deficits. Most frequent are extraxial bleeding and intraparenchimal lesions. Abdominal damages are the second cause of dead in the abused child. They can be asymptomatic and so they can be misdiagnosed. They are not so frequent but if they are present, they are letal. Conventional radiology, CT and MRI are very important in the management of child abuse because they allow to reveal multiorgan damages which, in some instances, can be specific of a child abuse.

[Use of expandable metal stents for gastroduodenal outlet obstruction]. / Uso degli stent metallici espansibili nelle ostruzioni maligne gastroduodenali.

Gastroduodenal obstruction is a preterminal event in patients with advanced malignancies of the stomach, pancreas and duodenum. Surgical gastrojejunostomy has been considered the traditional palliative treatment. The use of metallic stents is intended not to be curative but to provide nonsurgical palliation for the symptoms of obstruction. The advantages of this technique are the minor invasivity, the decrease in morbidity and mortality respect the surgical approach, the patient that can be discharged the day of or the day after the procedure and the better life expectation.

[Imaging of acute brain inflammatory disease]. / Imaging della patologia infiammatoria acuta dell'encefalo.

The central nervous system inflammatory disease can be due to any kind of infective agent (bacterial viral, fungal and parasitic), but entails also multiple sclerosis, a primary demyelinating disease in which the causal agent is unknown. MR imaging is, in most often, the procedure of choice, due to her multiplanar and multiparametric imaging, and to her better contrast resolution. The post-contrast imaging with double dose of gadolinium and late sequences enable visualisation of smallest pathologic foci or slightest blood-brain barrier alterations, with a sensibility very higher than post-contrast CT scan. In addition, RM provide to many functional informations, by means of diffusion, perfusion and spectroscopy studies, Bold technique for cortical activation studies and Fiber Tracking technique, in order to demonstrate pathologic modification earlier than they are evident on morphologic imaging. Functional imaging is also employed to monitor response to treatment and damage reversibility.

[CT and MR virtual colonscopy: indications, limits and comparison with conventional colonscopy]. / Colonscopia virtuale TC e RM: indicazioni, limiti e confronto con la colonscopia tradizionale.

Virtual endoscopy is a new method for studying the colon; it consists in acquisition of CT and MR images and to elaborate them with a workstation, to create endoluminal vision as like as traditional colonscopy, permitting the complete exploration of colonic lumen, also with stenotic tumors. The analysis of the differences between CT and MR colography shows like these two techniques present both advantages and disadvantages, such as the impossibility to perform MR in patients with pace-maker or in claustrophobic patients and the impossibility to perform CT with iodated agents in patients with renal failure or with a story of adverse reactions. The increased use of these techniques is due to the high sensitivity of last-generation CT and MR machine, to the increased spatial resolution, to specific softwares for digital cleaning of colon, to the introduction of high-end workstations and to the possibility of computed assisted diagnosis (CAD). So, it is desiderable that the increasing spread of multidetector CT devices and the future technical innovations, should have the effect to increase culture and experience in various diagnostic centers about CT-colography, making possible the spreading of virtual endoscopy as a screening tool.

[Imaging of median sternotomy complications]. / Imaging delle complicanze dopo sternotomia mediana.

Median sternotomy is the surgical technique of chosen for cardiac surgery. Although the complications after median sternotomy are not so frequent, these are associated to elevated mortality. The complications can interest the presternal compartment, the sternal compartment or the retrosternal compartment. Even if the clinical diagnosis of infection is not difficult for the clinician, it is nearly impossible to establish the depth of the infection. Multislice CT, thanks to the possibility to obtain thin layers and three-dimensional multiplanar reconstructions and Volume Rendering, turns out extremely useful for being able to demonstrate the extension and the depth of the infection. Of fundamental importance it is the elaboration of the images, executed on workstation, with which multiplanar reformatted and Volume Rendering images are obtained. The CT turns out useful moreover like guide for the execution of interventional procedures such as aspiration of material for bacteriological characterization or eventual positioning of a catheter for abscess drainage. The Magnetic Resonance, thanks to its high resolution of contrast and to its multiplanarity, finds one of its elective applications in the study of the flogistic and neoplastic processes of the soft tissues. A great limit of the MR is the possible generation of artifacts due to sternal suture.

Involvement of the limbic system in multiple sclerosis patients with depressive disorders.

This study investigates the relationship between depression and both anatomic and cerebral blood flow abnormalities in multiple sclerosis (MS) patients. Ten nondepressed MS patients were compared with 10 depressed MS patients matched for age, sex, and functional disability. Both groups were evaluated by means of neuropsychological tests, magnetic resonance imaging, and single-photon emission tomography imaging. There was no difference between the two groups with regard to the global cognitive score. Magnetic resonance imaging data showed no significant differences in the number, side, location, and area of the demyelinating lesions between the two groups; however, regional cerebral blood flow asymmetries in the limbic cortex did distinguish the two groups. Analysis of variance showed a significant effect of depression on the perfusion asymmetries in the limbic cortex. Finally, perfusion asymmetries in limbic cortex significantly correlated with depression test scores. Our findings suggest that depression in MS patients could be induced by a disconnection between subcortical and cortical areas involved in the function of the limbic system.

Association of trisomy 9p and band heterotopia.

Patients with the trisomy 9p syndrome and CNS abnormalities have been poorly assessed. We report a patient with trisomy 9p who showed band heterotopia on MRI. Abnormal neuronal migration is sufficiently frequent in patients with the trisomy 9p syndrome that brain MRI should be routinely considered in all patients with this syndrome.

Plasma endothelin-1 levels, pulmonary hypertension, and lung fibrosis in patients with systemic sclerosis.

PURPOSE: To investigate the behavior of circulating endothelin (ET)-1 concentrations in patients affected by systemic sclerosis, and to elucidate the possible relationships existing in this disease among plasma peptide levels, pulmonary hypertension, and lung fibrosis. PATIENTS AND METHODS: Circulating ET-1 levels were determined by reverse-phase, high-pressure liquid chromatography followed by sensitive radioimmunoassay in 20 patients affected by systemic sclerosis (18 women and 2 men, mean age 48.1 +/- 13.7 years) with or without pulmonary hypertension as evaluated by Doppler echocardiography, or lung fibrosis as measured by a score method based on lung examination by high-resolution computed tomography (HRCT). A group of 18 normal volunteers served as controls (15 women and 3 men, mean age 45.0 +/- 10.1 years). RESULTS: Plasma ET-1 levels were significantly higher (P < 0.001) in patients with systemic sclerosis (1.72 +/- 0.28 pg/mL) than in control subjects (0.63 +/- 0.06 pg/mL). Pulmonary artery systolic hypertension was detected in 10 patients (50%) with systemic sclerosis (56.2 +/- 18.0 mm Hg, range 37 to 97) versus none of the control subjects (30.2 +/- 2.2 mm Hg, P < 0.0001). Lung fibrosis was present in 12 patients (60%), with an HRCT overall score of 9.0 +/- 4.6. There were no significant differences in plasma ET-1 levels between patients with pulmonary hypertension (1.58 +/- 0.20 pg/mL) or without it (1.76 +/- 0.39 pg/mL, P = 0.188, not significant [NS]); or between patients with lung fibrosis (1.65 +/- 0.14 pg/mL) or without fibrosis (1.78 +/- 0.37 pg/mL, P = 0.290, NS). In particular, 6 patients had neither pulmonary hypertension nor lung fibrosis. In these patients, plasma ET-1 levels were similar compared with the others (1.85 +/- 0.49 versus 1.66 +/- 0.13, respectively; P = 0.180, NS). No correlations were observed between ET-1 levels and either pulmonary pressure levels or HRCT overall scores. CONCLUSIONS: The use of a sensitive assay, highly selective for ET-1, showed higher levels of circulating peptide in patients affected by systemic sclerosis than in control subjects. Neither pulmonary hypertension nor lung fibrosis was accompanied by a further rise in plasma ET-1 concentrations.

Computed tomography for the evaluation of intrathoracic invasion by lung cancer.

We conducted computed tomographic examinations of the chest in 171 patients with lung cancer whose disease was subsequently surgically staged; routine mediastinal exploration was undertaken in all patients undergoing thoracotomy (151), and in 20 patients only anterior mediastinotomy or mediastinoscopy was performed. We have considered three groups of patients: In Group I (including all 171 patients) mediastinal lymph nodes were evaluated for metastatic involvement; nodes were considered diseased when greater than 1 cm. Sensitivity, specificity, and accuracy were 95%, 83%, and 89%. Among these 171 patients, 34 (Group II) had a central tumor otherwise considered operable, which was shown on plain roentgenograms to be in contact with the mediastinum; infiltration of hilar and mediastinal vessels and of mediastinal tissues was investigated preoperatively with computed tomography and then ascertained at thoracotomy. Sensitivity, specificity, and accuracy were 68%, 72% and 70%. Twenty-seven patients (Group III) had a peripheral tumor abutting the pleural surface and suspected to invade the parietal pleura and chest wall; patients with evident bone infiltration were excluded. Sensitivity, specificity, and accuracy of computed tomography were 50%, 90%, and 65%.

Intracerebral schwannoma: CT and MR findings.

A case of intracerebral schwannoma in a 19-year-old man is reported. CT and MR findings were nonspecific, suggesting a primary glioma. The histologic features were of schwannoma.

Magnetic resonance imaging (MRI) of the brain in SLE: ECLAM and SLEDAI correlations.

Twenty-one unselected SLE patients were examined with Magnetic Resonance Imaging (MRI) for cerebral areas of high signal intensity (HSI). Nine patients (42.9%) had HSI and 6 (28.6%) had large (> or = 6 mm) lesions suggestive of cerebral involvement. Despite the lack of correlation among these lesions and clinical or immunological features, the SLEDAI and ECLAM indices were correlated to the number of large lesions (p < 0.002). Our findings suggest that brain MRI may be useful in the evaluation of SLE patients, not only those with evident neurologic symptoms, but also asymptomatic subjects with high disease activity indices.

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.

Ultrasound and computed tomography in staging of bladder tumours.

Eighty-seven patients with proven bladder tumours were retrospectively reviewed with ultrasound (US) and computed tomography (CT), in order to define the stage of the neoplasm. The tumours were divided into three groups with respect to the TNM classification system. Results indicate that US could predict an exact staging of the bladder tumours in 80.6% of cases in the first group (P1), 68.9% of cases in the second group (P2 - P3), and 90.0% of cases in the third group (P4). CT could predict an exact staging in 61.3% of the bladder tumours in the first group, 91.1% in the second group, and 90.0% in the third group. This finding suggests that the capability of US in detecting bladder tumours in stage P1 may avoid the use of CT, while in subsequent stages CT becomes valuable for the evaluation of extravesical invasions and lymph node metastasis.

Pre-operative staging of endometrial carcinoma: magnetic resonance imaging versus ultrasounds and hysteroscopy.

Ultrasound, hysteroscopy and magnetic resonance imaging has been considerated to assess the loco-regional or extrapelvic extension of the endometrial carcinoma. Sonography has demonstrated a certain inaccuracy in predicting myometrial invasion or the involvement of the canal. Hysteroscopy allows us to characterize neoplasia and to assess its extension in the cervical canal. MR imaging is more helpful in the diagnosis of channel invasion. The assessment of ovarian metastasis requires ultrasonography or coronal planes RM imaging. As regards the involvement of the pelvic and extrapelvic lymph nodes MR is more accurate than ultrasound scan.

[Radiologic staging after surgical, chemical, and radiation treatment of non-seminomatous tumors of the testis]. / La stadiazione radiologica dopo trattamento chirurgico, chemio e radioterapico dei tumori non seminomatosi del testicolo.

The aim of this work was to evaluate the clinic usefulness of Computed Tomography (CT) and Magnetic Resonance (RM) in the staging after surgery, radiotherapy and chemotherapy of the nonseminomatous germ cells tumours of the testis. The Authors discussed the CT and MR dimensional criteria for the diagnosis of retroperitoneal metastases of the nonseminomatous germ cells tumours and delineated their CT and MR morphologic appearances in detail. The density of the residual mass on CT was classified as solid, cystic and half-cystic. The retroperitoneal hematoma and lymphocele formed as a complication respectively of orchiectomy and retroperitoneal lymphadenectomy can be misinterpreted to represent metastatic disease on post operative staging CT scans. Early recognition of this complication are crucial if unnecessary treatment is to be avoided. Finally the Authors evaluated, in patients affected from nonseminomatous germ cells tumours of the testis, the possibility to characterize with CT and MR imaging the retroperitoneal mass. The density and character of the residual mass on CT scan did not reliably predict the histology. On the basis of tumor consistency and signal intensity in T1 and T2 weighted images, MR cannot yet warrant any conclusion about the ultimate effect of chemotherapy.

[Clinical use of endorectal coil MR in the study of prostatic pathology with special reference to hyperplasia and carcinoma]. / Impiego clinico della RM con bobina endorettale nello studio della patologia prostatica con particolare riferimento all'iperplasia e al carcinoma.

In this report we evaluated the usefulness of endorectal surface coil MR imaging in the study of prostatic anatomy, age-related changes, benign prostatic hyperplasia and carcinoma. At present, endorectal coil MR imaging seems to be one of the most important diagnostic steps in the study of prostatic diseases, because it is the technique that allow to gain very high resolution images.

[Imaging of neuroendocrine tumors]. / Imaging dei tumori neuroendocrini.

Neuroendocrine tumors (NET) of the pancreas are distinguished in functional (85%) and non functional (15%) in relation to the production and release of the hormone produced. Functional tumors show early, because the neoplasm release the hormone produced when they are still small. Non functional tumors show late when the tumor grows. The localization and the evaluation of the extensive of these tumors has come fundamentally important both in correct presurgical detection and also in the diagnosis of metastases which excluded surgery. Also, as the survival of 20% of the patients with metastases is only five years, the use of non-invasive imaging techniques is very important for the evaluation of results of the various therapies (chemotherapy, interferon, somatostatin). Recent studies have shown that in patients with Zollinger-Ellison syndrome, SRS is the most sensitive non invasive method in localizing primitive tumors and metastases. The accuracy of this technique has not yet been provided in the study of tumors like insulinomas which do not have a high percentage of somatostatine receptors on their cell membranes. The sensitivity obtained in recent studies on a large number of patient and the low cost, lower than all the other imaging technique in use today, surely make SRS the first choice in the study of NET. Where SRS is negative and surgery is possible, Spiral CT or better still MRI is the best tool to check the results of chemotherapy in patients with hepatic metastases (already detected by SRS), because it is easier to compare the changes in size and morphology of metastases.