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C Zuiani

Publications and source records attributed to C Zuiani.

At least 19 recordsLinked to original sources
PubMed2006

Ultrasonographic analysis in vitro of parietal thickness of lower limb varicose veins.

PURPOSE: The aim of this study was to evaluate the ability of ultrasound (US) to measure the parietal thickness of varicose veins. MATERIALS AND METHODS: In a blind in vitro analysis, 28 great saphenous veins, obtained after stripping surgery from 28 patients with chronic venous insufficiency, were examined with a digital US scanner ATL-HDI5000, linear 5-1 to 2-MHz broadband probe, compound imaging technique and analogic-digital zooming. We obtained one to three progressive measurements for each vein wall (total 67 parietal thicknesses). The samples, fixed in formalin, were sent to the pathology laboratory: sections were obtained at the same level of the sonographic planes, and images were obtained by digital camera mounted on an optical microscope. Measurements obtained at histology were considered as the gold standard. K-statistic was applied to compare sonographic and histologic measurements. RESULTS: Considering only the hypoechoic wall portion, 29/29 (100%) diagnoses of hypotrophy (K=0.91), 19/22 (86%) diagnoses of normotrophy (K=0,47) and 12/16 (75%) diagnoses of hypertrophy (K=0.7) were obtained by sonography. CONCLUSIONS: In our preliminary experience, the in vitro study of varicose veins allows precise, at least morphological, detection of hypotrophic walls. If these preliminary data are confirmed in vivo, sonography could be used to discriminate patients eligible for conservative treatment instead of surgery.

Adult↗
PubMed2006

Supraspinatus tendon US morphology in basketball players: correlation with main pathologic models of secondary impingement syndrome in young overhead athletes. Preliminary report.

PURPOSE: The purpose of this study was to investigate supraspinatus tendon sonographic morphology in a population of young overhead athletes in correlation with main pathologic models of secondary shoulder impingement syndrome. SUBJECTS AND METHODS: Between April and May 2004, 20 subjects (ten professional basketball players and ten non-athlete controls of the same age, weight and height ranges) underwent bilateral, standardised, sonographic sholulder examination to evaluate supraspinatus echotexture, supraspinatus and subacromial bursa thickness, subacromial space width (cutoff of 7 mm) and dynamic anterior impingement beneath the acromial margin. RESULTS: All subjects were right handed. No symptomatic controls were found. Four players showed signs and symptoms of right atraumatic shoulder instability (two cases) or supraspinatus impingement with anterior pain (one right and one left shoulder). Subacromial space width was reduced in five right-dominant players' shoulders (three symptomatic and two asymptomatic) versus zero controls (p<0.05) and in eight players' shoulders versus zero controls on total shoulders (p<0.05). No other significant differences were observed between the two groups in sonographic parameters considered. CONCLUSIONS: Despite the study limitations, ultrasonography (US) is able to detect subacromial space narrowing in young overhead athletes as early shoulder impingement sign, according to the continuum impingement-instability pathologic model.

Adolescent↗
PubMed2005

Postmenopausal hormone therapy and mammographic breast density.

OBJECTIVE: The aim of this study was to evaluate the effects of different types of hormone replacement therapy (HRT) on mammographic density. MATERIALS AND METHODS: In a prospective 1-year study, 103 postmenopausal women were randomized to receive tibolone 2.5 mg/die, continuous conjugated equine estrogens 0.625 mg/die plus medroxyprogesterone acetate (MPA) 5mg/die or placebo. Mammograms were performed at baseline and after 12 months of treatment. Mammographic density was quantified according to the Wolfe classification. RESULTS: After 12 months of HRT 16 of the 35 patients (45.1%) receiving continuous combined hormonal therapy showed an increase of breast density change in the Wolfe classification. After treatment with tibolone, an up grading in breast density, according to Wolfe's classification, was found in 2 of the 43 patients (2.3%). No changes were recorded in the 25 patients of the control group. The difference between the group treated with continuous combined hormonal therapy and the control group was highly significant (p<0.001). The difference in breast density between patients in treatment with tibolone and the control group was not statistically significant (p=0.34). DISCUSSION: Continuous combination HRT may be more commonly associated with an increase of mammography density than tibolone treatment.

Breast↗
PubMed2002

Radiation-induced angiosarcoma of the breast: case report and self-criticism of therapeutic approach.

Angiosarcoma (AS) of the breast is a rare and highly aggressive vascular cancer. It presents as a primitive or radioinduced form. The case of a 46-year-old woman who underwent quadrantectomy of the breast plus axillary lymph node dissection and radiotherapy postoperatively (QUART) for ductal infiltrant carcinoma is reported in the following. Ten years later, the patient underwent mastectomy with immediate reconstruction, for local recurrence that was diagnosed as an AS of the breast at final pathological examination. She did not receive any adjuvant treatment due to local post-operative complications related to breast reconstruction. We criticize our therapeutic approach and we recommend more attention about local recurrence suggesting that tru-cut needle biopsy of local recurrence of the breast after QUART, should be the correct diagnostic approach.

Biopsy↗
PubMed2002

Ductal carcinoma in situ: is there a role for MRI?

The purpose of our study is to report personal experience about 28 cases of Ductal Carcinoma In Situ (DCIS) studied with Magnetic Resonance Imaging (MRI). From September 1995 to December 2001, 28 women affected by DCIS lesions underwent contrast enhanced MRI. All patients were submitted previously to mammographic examination. The results of histopathological examination included: 19 DCIS and 9 DCIS with associated microinvasive component or microfoci of invasive ductal carcinoma (IDC). MRI was performed with a 1 T system. A three dimensional fast low-angle shot (FLASH) pulse sequence was used, with a repetition time (TR) of 14 ms, an echo time (TE) of 7 ms and a flip angle of 25 degrees. We evaluated the morphologic features of the enhancement, the enhancement rate and the signal time intensity curve. On MRI 26 out of 28 (92.85%) DCIS lesions showed contrast uptake. 17 out of 19 pure DCIS lesions demonstrated contrast enhancement: 5 showed a low, 7 indeterminate and 5 a strong enhancement. Morphologically, the enhancing lesion was focal in 9, segmental in 5 and linear branching in 3. Wash out was found in 5 cases, plateau curve in 9 and Type I curve in 3. There were 5 cases of multifocality. All DCIS with associated microinvasion demonstrated contrast enhancement: 2 out of 9 cases showed a low enhancement, 4 out of 9 showed an indeterminate enhancement and 3 out of 9 showed a strong enhancement. Morphologically the enhancing lesion was focal in 3 out of 9, segmental in 5 and linear branching in 1. The wash out was demonstrated in 4 cases out of 9, plateau curve in 4 and Type I curve in 1. There were 3 cases of multifocality. In conclusion, MR imaging sensitivity for DCIS detection is lower than that achieved for invasive breast cancer; however, contrast enhanced MR imaging can depict mammographically occult foci of DCIS. The MR imaging technique is of complementary value in better description of tumor size and in additional malignant lesions detection.

Aged↗
PubMed2002

The Italian multi-centre project on evaluation of MRI and other imaging modalities in early detection of breast cancer in subjects at high genetic risk.

This report presents the preliminary results of the first phase (21 months) of a multi-centre, non-randomised, prospective study, aimed at evaluating the effectiveness of contrast-enhanced magnetic resonance imaging (MRI), X-ray mammography (XM) and ultrasound (US) in early diagnosis of breast cancer (BC) in subjects at high genetic risk. This Italian national trial (coordinated by the Istituto Superiore di Sanità, Rome) so far recruited 105 women (mean age 46.0 years; median age 51.0; age range 25-77 years), who were either proven BRCA1 or BRCA2 mutation carriers or had a 1 in 2 probability of being carriers (40/105 with a previous personal history of BC). Eight cases of breast carcinomas were detected in the trial (mean age 55.3 years, median age 52.5; age range 35-70 years; five with previous personal history of BC). All trial-detected BC cases (8/8) were identified by MRI, while XM and US correctly classified only one. MRI had one false positive case, XM and US none. Seven "MRI-only" detected cancers (4 invasive, 3 in situ) occurred in both pre- (n = 2) and post-menopausal (n = 5) women. With respect to the current XM screening programmes addressed to women in the age range 50-69 years, the global incidence of BC in the trial (7.6%) was over ten-fold higher. The cost per "MRI-only" detected cancer in this particular category of subjects at high genetic risk was substantially lower than that of an XM-detected cancer in the general women population. These preliminary results confirmed that MRI is a very useful tool to screen subjects at high genetic risk for breast carcinoma, not only in pre-, but also in post-menopausal age, with a low probability of false positive cases.

Adult↗
PubMed2001

[Application of a computer-aided detection (CAD) system to digitalized mammograms for identifying microcalcifications].

PURPOSE: It is estimated that during mammographic screening programs radiologists fail to detect approximately 25% of breast cancers visible on retrospective review; this percentage rises to 50% if minimal signs are considered. Independent double reading is now strongly recommended as it allows to reduce the rate of false negative examinations by 5-15%. Recent technological progress has allowed to develop a number of computer-aided detection (CAD) systems. The aim of CAD is to help radiologists interpret lesions by serving as a second reader. In this study the authors developed and applied a CAD system to measure its ability to microcalcifications detect and compare its performance with that of a human observer. MATERIAL AND METHODS: The study was performed as part of the CALMA (computer-aided library for mammography) project of the Pisa section of the National Institute of Nuclear Physics. The aim of this project is to set up a large database of digital mammograms and to develop a CAD system. Our study series consisted of 802 mammograms - corresponding to 213 patients - digitalized between March and June 2000. We performed traditional mammography and then digitalized the mammograms using a CCD linear scanner (pixel size of 85 x 85 microm2, 12 bits). The images were evaluated by two radiologists with similar experience and then by the CAD system. This CAD system searches for microcalcifications by using ad hoc algorithms and an artificial neural network (Sanger type). RESULTS: The number of clusters in our database was 141 corresponding to 140 images; 692 images were non pathological. The CAD system identified a variable number of clusters depending on the threshold values. The threshold value is a number over which the probability of finding a lesion is highest. With thresholds of 0.13 and 0.14 the CAD system identified 140/141 clusters (99.3%); with a threshold of 0.15 it identified 139/141 clusters (98.6%); with a threshold of 0.16, 137/141 (97.2%); with a threshold of 0.18, 133/141 (94.3%); with thresholds of 0.18 and 0.20, 130/141 (92.2%). With threshold values of 0.13, 0.14, 0.15, 0.16 and 0.17 the system's sensitivity was greater than 82%, whereas with values of 0.18 and 0.20 it was greater than 80%. The number of false positive region of interest (ROI) / image was greater with low threshold values: in particular, thresholds of 0.13 and 0.14 yielded 16 false positives /image, thresholds of 0.15 and 0.16 yielded 9 and 7 false positives/image, and both 0.18 and 0.20 only 5/image. DISCUSSION: ROC curve shows how the use of high threshold values determined a very high specificity despite very low sensitivity rates. Conversely, low threshold values allowed to have a high sensitivity and a very low specificity. The best performance of our CAD system was obtained with threshold values at 0.15 and 0.16. In fact these thresholds resulted in a high sensitivity (greater than 82%) with an acceptable number of false positives/image, 9 and 7/image, respectively. It is not yet known how radiologists can deal with large numbers of false positives in screening programmes but in our opinion the most important feature of a good CAD system is a high sensitivity. CONCLUSIONS: In the near future the use of CAD systems will be widespread and easier to apply to everyday practice above all in centers where digital mammography is performed. Mammograms could be directly shown to radiologists after the CAD system has selected the ROI and analysed the images. Thanks to its high sensitivity and despite its low specificity CAD represents a concrete aid for radiologists.

Breast Diseases↗
PubMed2001

[Papillary lesions of the breast: diagnostic imaging and contribution of percutaneous needle biopsy with 14G needle].

PURPOSE: To evaluate the presence of suggestive mammographic, US, color-Doppler, RM findings of 33 PLB and to show the accuracy of the large-core biopsy in evaluating these lesions. MATERIAL AND METHODS: A retrospective review of imaging-guided large-core biopsy of 860 consecutive lesions revealed that PLB were diagnosed in 31/33 cases and 3 were suspicious papillary lesions. Surgical correlation was available for all these lesions. Mammography and US were performed in all patients, Color-Doppler in 13/33 and MR in 10/33. RESULTS: Histological findings by percutaneous biopsy demonstrated 26 (79%) benign, 3 (9%) atypical, and 4 (12%) malignant lesions. Histological findings after surgery confirmed the diagnosis for benign and malignant lesions, while of the 3 atypical lesions, 1 was benign and 2 were malignant. One encysted papillary carcinoma in situ at core-biopsy was classified as invasive papillary carcinoma after surgery. PLB were usually found (52%) in subareolar location and the mean size was 17 mm (range 5-60 mm). The most frequent mammographic appearance of benign PLB was of a well-defined (71%), oval (53%) mass. The microcalcifications had variable features; they were isolated in 3/27 (15%) cases and associated with masses in 4/27 (20%). The mammographic finding of papillary carcinoma was of a well-defined (50%) or ill-defined, oval (50%) or lobulated (50%) mass, but never of a spiculated mass. US finding of the benign PLB most commonly showed a well-defined (84%), oval (84%), complex solid/cystic (52%) mass with frequently (60%) posterior enhancement. US finding of papillary carcinoma was of a well-defined (50%) or ill-defined (50%), oval (50%) or lobulated (50%) mass, most commonly solid-inhomogenous-hypoechoic. Color-Doppler showed high blood flow in 8/10 benign PLB and in 2/3 malignant PLB. Contrast-enhanced MR imaging demonstrated usually well-circumscribed, round masses (71%). The intensity/time curve showed marked focal enhancement (peak signal intensity over 70% at the first minute) in both benign and malignant lesions. DISCUSSION: Often the patients with PBL were symptomatic (for presence of nipple discharge or palpable mass). 31/33 papillary lesions identified at the subsequent imaging-guided large-core biopsy and in the 3/33 remaining lesions percutaneous core-biopsy required a subsequent surgical biopsy for the atypical papillary lesions. US proved to have the highest sensitivity, showing the suggestive feature of a frond-like mass within a dilated duct, and color-Doppler demonstrated high blood flow (which should be considered in differential diagnosis of galactocele). Mammographic finding of papillary lesions was often consistent with benign lesions (fibroadenoma, cyst). MR confirmed the high vascularization of these lesions, showing marked enhancement of the solid component. CONCLUSIONS: US, with Color-Doppler, proved to be the most useful examination for the identification and demonstration of the solid component of these lesions, which, observed further diagnostic investigation. As no definite mammographic, sonographic or RM pattern could be identified to differentiate between benign and malignant PLB, core-biopsy was required. Percutaneous biopsy has shown to be reliable in the diagnosis of benign and malignant PLB (without any false negative): infact, any atypical lesions require surgical examination. The framing of benign and malignant PLB with imaging and core-biopsy was useful because the frequent association of benign PLB with concurrent or subsequent breast carcinoma suggests surgical excision and radiological follow-up.

Adult↗
PubMed2000

[Diagnostic imaging of lobular carcinoma of the breast: mammographic, ultrasonographic and MR findings].

PURPOSE: To evaluate the most frequent mammographic, US and MR findings of invasive lobular carcinoma and the role of MRI in defining multifocality and/or multicentricity of this tumor histotype. MATERIAL AND METHODS: We studied 45 lobular carcinomas (39 patients) were selected from 421 breast cancers. Core biopsy with a 14 G needle was performed in 39 cases, under US guidance in 36/39 and under mammographic guidance in 3/39 cases. Surgical biopsy was performed in 2 cases and the diagnosis could be made only after mastectomy in 5 cases. All patients were examined with mammography and US and (10-13 MHz) and 8 also with MRI. RESULTS: 28/46 palpable lesions (60.9%). Core biopsy correctly diagnosed 38/39 lesions (97.4%). The most frequent mammographic findings was that of a nodular opacity without microcalcifications (34.8%), followed by a mass with spiculated borders (30.4%). Microcalcifications were seen in one case only (2.2%). Mammography detected no abnormalities in 15.2% of cases, but US showed a lesion in 2 of these cases. The most frequent US pattern was that of a hypoechoic lesion (43.5%), followed by posterior US beam attenuation. No US signs of abnormality were seen 15.2%. MRI correctly detected 13 lesions. Contrast enhancement was greater than 70% at one minute in 10 cases and greater than 40% in one case; two lesions exhibited atypical slow contrast enhancement, peaking at 5 minutes. MRI detected 5 lesions missed at both mammography and US and showed multifocal (3 and 2) lesions where the other techniques had detected one lesion only. DISCUSSION: At mammography and US invasive lobular carcinoma exhibits no different features than ductal carcinoma but is difficult to identify especially in its early stages. US is a useful tool especially to characterize mammography-detected lesions but in our experience it also demonstrated 2 lesions missed at mammography. MRI is a precious examination to define the multifocal, multicentric or bilateral character of invasive lobular carcinoma. CONCLUSIONS: Invasive lobular carcinoma of the breast is often very difficult to diagnose. Thus, we suggest the use of integrated diagnostic imaging with mammography, US and, in some cases, MRI for earlier diagnosis and to identify further tumor localizations.

Adult↗
PubMed1999

Diagnostic accuracy of perforated compression grid approach for mammographically guided core needle biopsy of breast lesions.

The aim of this study was to evaluate the diagnostic accuracy of large core breast biopsy with the use of the perforated compression grid (PCG) in a series of 106 consecutive mammographically detected breast lesions. The PCG consists in a fenestrated paddle that replaces the usual mammographic compressor. Each hole in the grid is marked by letters and numbers in order to obtain the coordinates of the area to biopsy. By analysing the two orthogonal projections, the depth of the lesion in the breast is calculated. With the breast positioned in the PCG, a skin incision is made. After calculations about the depth of needle insertion, the tip of the needle is inserted proximally to the target area. In such a way, taking into consideration the total running of the needle (23 mm), a correct sampling is assured, and multiple needle passes are performed. Sensitivity was of 90.62 and 90.90%, specificity was of 100 and 95.45% and positive predictive value was of 100 and 90.90% by excluding and including suspicious diagnoses, respectively, for each computation. In conclusion, the study indicated that image-guided core biopsy performed by the approach of PCG is a cost-effective, simple and accurate technique for the diagnosis of breast lesions, and it could be proposed as a low-cost alternative where the stereotactic equipment is not available.

Adult↗
PubMed1999

Functional MR with use of FLASH sequences in the evaluation of the phono-articulatory tract.

The aims of this study are to determine visualization of normal phonation structures with the use of MR fast sequences and anatomical reference indices which can be used in evaluating upper resonator pathologies. A total of 12 normal subjects were studied, a 1 T system, a volumetric receiving head and neck coil and FLASH sequences for one sagittal and two coronal scans. Each subject was instructed to take a deep breath and then to produce the vowel sounds for the entire duration of the scan. The movement of the following anatomical structures were considered: lips, tongue, soft palate, pharynx and epiglottis. For each subject sagittal scans were used to measure the minimal palate tongue distance (p-t), the minimal anterio-posterior diameter of the mesopharynx (mp), and the epiglottis excursion angle (ep) with respect to the plane determined by the false vocal cords. Our results were compared with a diagrammed representation of tongue movements (vocal trapezium). This study underlines the validity of MR imaging techniques in the study of the phono-articulatory tract, because MR provided good detail of the phono-articulatory structures enabling an overall functional evaluation. MR would appear useful in evaluating defects in the velum and palate, in staging of oropharyngeal neoplasms and in surgical reconstructions of the tongue.

Adult↗
PubMed1999

Human mammary gland and breast carcinoma contain immunoreactive inhibin/activin subunits: evidence for a secretion into cystic fluid.

OBJECTIVE: Inhibins and activins are members of the transforming growth factor beta superfamily and are known to modulate the growth and differentiation of several cell types. The present study investigated the localization of inhibin and activin subunits in human normal and pathological breast tissues. DESIGN: A cross-sectional study comparing the expression of inhibin/activin subunits alpha, betaA and betaB in surgical specimens from women undergoing reductive mammoplasty (classified, according to the phase of the menstrual cycle, as follicular, luteal, or postmenopausal), and patients submitted to lumpectomy for fibrocystic disease, benign (intraductal papilloma, adenomyoepithelioma, and hamartoma) or malignant breast neoplams (intraductal, intralobular, and invasive carcinoma). METHODS: Immunohistochemistry was used to localize inhibin alpha and activin betaA and betaB subunits in the cytoplasm of epithelial cells of mammary glands. Dimeric activin A, inhibin A and inhibin B were measured by specific two-site enzyme immunoassay in the cystic fluid collected from patients with fibrocystic disease. RESULTS: An intense staining for the alpha inhibin subunit and a mild staining for betaA and betaB subunits were present in samples obtained from normal breast tissue regardless of menstrual cycle phase, and in fibrocystic disease and benign neoplasms. Carcinoma cells stained weakly to moderately for alpha subunit and were negative for betaA and betaB subunits. Fibrocystic disease was associated with absence of betaA subunit expression in normal epithelial cells and intense staining for all subunits in the apocrine cells. Immunoreactive inhibin A, inhibin B, and activin A were also present in cystic fluid, suggesting a local secretion of these proteins. CONCLUSION: These data suggest a local expression and secretion of inhibin and activin in human normal, fibrocystic disease and neoplastic breast tissues. The low expression of these proteins may facilitate abnormal cell proliferation in breast carcinoma.

Activins↗
PubMed1999

[Atypical ductal hyperplasia of the breast. Its diagnostic imaging and the role of percutaneous needle biopsy with a 14-gauge needle].

PURPOSE: To investigate the yield of core biopsy in the histologic characterization of atypical ductal hyperplasia (ADH) and to assess the radiological patterns, if any, of this condition. MATERIAL AND METHODS: January 1993 to October 1997 we studied 553 lesions, 8 of them with a diagnosis of ADH made on microhistologic samples obtained with 14G needles. Biopsy was performed under US guidance in 81.7% of cases and under mammographic guidance in 18.3%. The breast lesions were studied with mammography, US and MRI, the latter in one case. ADH was diagnosed by strict application of Page's and lesion extent criteria. RESULTS: Seven of 8 lesions with a core biopsy diagnosis of ADH were submitted to surgical biopsy. The diagnosis was changed in as many as 6 of 8 cases, into typical ductal hyperplasia (1 case) and carcinoma (1 papilliferous, 3 ductal infiltrating and 1 in situ lesions). ADH was confirmed in one case only. DISCUSSION: In agreement with other authors, we found no specific radiological patterns of ADH. Moreover, the core biopsy diagnosis of ADH requires a surgical biopsy, because ADH is often associated with carcinoma. CONCLUSIONS: Surgical biopsy is needed to diagnose ADH and therefore it is useless to perform more invasive procedures than 14G core biopsy.

Biopsy, Needle↗
PubMed1998

Transcranial Doppler: state of the art.

INTRODUCTION: Transcranial color Doppler sonography permits the accurate assessment of intracranial arteries. The latest Doppler units, using the color and power techniques, can show even very small flow volumes (1 x 1 mm). Low frequency (2-2.5 MHz) and very focused transducers are used in transcranial color Doppler. The skull is a very strong barrier for ultrasounds, which requires the use of some acoustic windows like some thin portions of the skull bone or some natural skull foramina. The use of echocontrast agents in color Doppler seems to increase the applications of transcranial studies. OBJECTIVE: (1) To report on transcranial color Doppler technique and findings. (2) To assess the role of contrast agents in the visualization of intracranial vessels. (3) To define the main indications of this technique. MATERIAL AND METHODS: The temporal, the orbital and the suboccipital are the main acoustic windows used for transcranial color Doppler studies. We use phased-array transducers (2-2.5 MHz) and, preferrably, the echocontrast agent. We examined 15 patients with severe internal carotid artery stenoses after the infusion of Levovist (Schering AG, Berlin, Germany) suspension (8 ml at 300 mg Galactose/ml, infused at 0.5 ml/s). RESULTS: Levovist infusion permitted to depict the main intracranial vessels in all cases. The middle and the anterior cerebral arteries are shown through the temporal window. The former is the main cerebral artery, it is the easiest to identify and presents the highest peak systolic velocity. The orbital window can be used to visualize the ophthalmic artery and the internal carotid artery siphon, while the vertebral and the basilar arteries are demonstrated through the suboccipital window. DISCUSSION: We report the most important findings and discuss the main indications of transcranial color Doppler studies. In addition to flow presence and direction, the main indices of arterial flow can be measured thanks to contrast agent administration, namely the peak systolic velocity, the end diastolic velocity, the resistance index and the pulsatility index. A morphological assessment of the Willis circle can also be carried out with color and power Doppler. Functional studies can be performed to assess the residual autoregulatory function of the cerebral circle in the patients with internal carotid artery stenosis or occlusion. The development of intracranial collateral circles can also be studied in these patients. Moreover, the M1 segment of the middle cerebral artery and the internal carotid artery siphon can be demonstrated directly. Transcranial color Doppler is also a useful tool to detect vasospasm after subarachnoid hemorrhage and to monitor blood flow velocity in the middle cerebral artery during carotid endarterectomy. The assessment of blood supply to arteriovenous malformations and to intracranial neoplasms is another application. CONCLUSION: With reference to internal carotid stenoses, the main applications of transcranial color Doppler are the study of intracranial vessels, of intracranial arterial stenosis, of arteriovenous malformations and of Willis circle aneurysms, as well as the monitoring of blood flow velocity during carotid endarterectomy. Echocontrast agents play an important role in the visualization of intracranial vessels.

Arterial Occlusive Diseases↗
PubMed1998

Contrast media in liver sonography: correlation with enhanced dynamic magnetic resonance imaging.

Both color Doppler sonography and magnetic resonance are imaging techniques which do not use ionizing radiations, but despite this common feature there remain many differences between them. Thus, color Doppler sonography is a cost-effective technique using mechanical waves and providing real-time images while magnetic resonance imaging is much more expensive, uses magnetic fields and radiofrequency energy and provides static images. The former method is very sensitive in detecting focal liver lesions > 1 cm, but its specificity in characterization is not as good, not even with the color Doppler technique. The main differences between color Doppler sonography, with and/or without echocontrast agents, and contrast-enhanced (Gadolinium chelates) dynamic magnetic resonance imaging in focal liver lesions can be summarized as follows: (1) magnetic resonance imaging depicts tumor vascularization only after paramagnetic contrast media injection. Enhanced images completely depend upon the contrast agent and cannot be achieved without it. In contrast, color Doppler signal is not modified by the contrast agent, it just becomes stronger. (2) Contrast-enhanced magnetic resonance signal (as well as contrast-enhanced computed tomography signal) provides more pieces of information than color Doppler signal about the flow characteristics of liver nodules--i.e. it shows not only blood flow (hyper-/hypovascular nodule), but also the interstitial spread of the agent and its wash-out. For example, hepatocellular carcinoma and focal nodular hyperplasia have similar perfusion while agent spread and wash-out decrease very quickly in the former and more slowly in the latter, except for the low decrease of the central scar. (3) Color Doppler technology improvements, higher sensitivity to slow flows and better signal/noise ratio reduce the applications of contrast-enhanced sonography in focal liver lesions because the agents modify only sensitivity and not the imaging in slow flow studies. (4) The higher cost of contrast studies is justified only in selected cases, namely treatment follow-up in the lesions with rich pretreatment vascularization. Finally, the higher cost of contrast magnetic resonance studies is justified to increase sensitivity and especially to allow lesion characterization.

Carcinoma, Hepatocellular↗
PubMed1998

Retroperitoneal nodular fasciitis: magnetic resonance imaging (MRI) and pathological features.

A case of pelvic nodular fasciitis, with particular reference to its peculiar radiological and pathological features is described. Only a few cases of pelvic nodular fasciitis are reported in the English literature and at the best of our knowledge, this is the first case of retroperitoneal origin. This report discusses the role of MRI in the characterization of soft tissue masses. No specific MRI findings of nodular fasciitis were identified and MRI doesn't add any contribution to the differential diagnosis between benign and malignant lesions. As a consequence, the histopathological examination is necessary for a definitive diagnosis.

Journal Article↗
PubMed1996

Primary motor and sensory cortex activation during motor performance and motor imagery: a functional magnetic resonance imaging study.

The intensity and spatial distribution of functional activation in the left precentral and postcentral gyri during actual motor performance (MP) and mental representation [motor imagery (MI)] of self-paced finger-to-thumb opposition movements of the dominant hand were investigated in fourteen right-handed volunteers by functional magnetic resonance imaging (fMRI) techniques. Significant increases in mean normalized fMRI signal intensities over values obtained during the control (visual imagery) tasks were found in a region including the anterior bank and crown of the central sulcus, the presumed site of the primary motor cortex, during both MP (mean percentage increase, 2.1%) and MI (0.8%). In the anterior portion of the precentral gyrus and the postcentral gyrus, mean functional activity levels were also increased during both conditions (MP, 1.7 and 1.2%; MI, 0.6 and 0.4%, respectively). To locate activated foci during MI, MP, or both conditions, the time course of the signal intensities of pixels lying in the precentral or postcentral gyrus was plotted against single-step or double-step waveforms, where the steps of the waveform corresponded to different tasks. Pixels significantly (r > 0.7) activated during both MP and MI were identified in each region in the majority of subjects; percentage increases in signal intensity during MI were on average 30% as great as increases during MP. The pixels activated during both MP and MI appear to represent a large fraction of the whole population activated during MP. These results support the hypothesis that MI and MP involve overlapping neural networks in perirolandic cortical areas.

Adult↗