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D Caramella

Publications and source records attributed to D Caramella.

At least 19 recordsLinked to original sources
PubMed1997

Usefulness of echo-color Doppler in differentiating parathyroid lesions from other cervical masses.

The aim of our study was to clarify possible differential color Doppler US features between parathyroid lesions and other cervical masses. A total of 56 parathyroid lesions in 54 patients with primary hyperparathyroidism were preoperatively examined with color Doppler sonography. Color Doppler flow patterns were compared with those of 72 thyroid nodules and 20 cervical lymph nodes. In 38 parathyroid lesions a correlation between color Doppler patterns and size, location, and pathological findings was performed. Color Doppler sonography showed five vascular distribution patterns: pattern I, absence of flow; pattern II, focal peripheral flow ("vascular pole") with arterial Doppler spectrum; pattern III, peripheral flow; pattern IV, internal flow ("parenchymal pattern"); pattern V, peripheral and intranodular flow. Pattern I was not specific for any cervical lesion considered. Conversely, pattern IV was observed solely in parathyroid lesions, and pattern II was observed in only one nonparathyroid lesion (thyroid nodule). Mixed pattern (pattern V) was observed solely in thyroid nodules. In addition, pattern III was a characteristic finding of thyroid nodules and was observed in only one parathyroid lesion. Color Doppler patterns of the parathyroid masses did not correlate with the size of the lesion or pathological findings, but only with the location of the gland. Our study showed that color Doppler assessment of parathyroid lesions is a useful integration of gray-scale US and may be helpful in distinguishing parathyroid lesions from other cervical masses.

Adenoma↗
PubMed1997

Ex-vivo MR imaging of liver intracellular contrast agents.

The objective is to evaluate whether an ex-vivo model can be used to test intracellular contrast agents for MR imaging of the liver. T1 weighted inversion recovery, proton density spin echo and T2* weighted gradient echo images of the liver were acquired at 0.5 T in 10 rats before and 30 min after intravenous injection of 0.075 mmol/kg Gadolinium benzyloxypropionictetraacetate (Gd-BOPTA, n = 5) or 0.015 mmol/kg dextran magnetite (DM, n = 5), Four additional animals served as controls. After exsanguination and perfusion with saline and formalin, specimens of the liver and brain were embedded in an agar gel and examined with MR imaging one to three weeks later using the same protocol. In-vivo, the mean liver signal enhancement caused by Gd-BOPTA in T1, proton density and T2* weighted images was +23%, +28% and -70%, respectively. The mean liver signal enhancement caused by DM was -71%, -76% and -94%. In-vitro, no signal change was seen in the brain of animals injected with Gd-BOPTA and DM as compared to controls. Liver signal was increased by Gd-BOPTA and decreased by DM. Mean liver enhancement rate induced by Gd-BOPTA was +22%, +5% and +27% for T1, proton density and T2* weighted images, respectively. Mean liver enhancement rate induced by DM was -27%, -19% and -31%. MR imaging signal changes induced by liver intracellular contrast agents are still appreciable in an ex-vivo model. The latter might be useful for for preliminary investigation of intracellular contrast agents for MR imaging of the liver.

Animals↗
PubMed1996

Teleradiology: state of the art in clinical environment.

Teleradiology may even be a tautology since communication is an essential part of radiology. The value of a radiological report is strictly dependent on how fast and clearly it is transmitted to the referring physician. The radiologist has therefore learnt to combine imaging expertise with communicator's skills. However, the term teleradiology is usually reserved to define the instances in which computers and digital networks help to reduce the limitations imposed by the physical distance between radiologists and between radiologist and referring physician. In this paper the main clinical applications of teleradiology will be presented, distinguishing between intra-institutional teleradiology (that involves more units belonging to the same department or to the same hospital) and inter-institutional teleradiology (more classically aimed at primary interpretation and subspecialty consultation). Finally a brief mention will be made concerning the potential for Internet to provide radiologists with new professional and educational opportunities.

Computer Communication Networks↗
PubMed1996

Use of a biocompatible fiducial marker in evaluating the accuracy of computed tomography image registration.

RATIONALE AND OBJECTIVES: Accurate registration of computed tomography (CT) images to the patient is crucial for computer-assisted surgery. Markers used in roentgen stereo-grammetric analysis (RSA) can be located in a CT scan using a novel approach and also can be located physically. Roentgen stereo-grammetric analysis data act as "ground truth" for the three-dimensional marker locations. METHODS: Two foam-bone phantoms were marked. The markers were scanned seven times with RSA, three times with axial CT, and contacted four times with a coordinate measuring arm. Root-mean-square (RMS) errors were derived for the registrations. RESULTS: Computed tomography and RSA data register to 0.15 mm RMS error. Computed tomography and arm data register to 0.25 mm. The markers are biocompatible, and the coordinate measuring arm is usable in an operating room. CONCLUSIONS: Typical in vitro registration errors are approximately 2 mm. The authors have developed a marker that provides superior registration, and a procedure that can be used for in vivo studies.

Biocompatible Materials↗
PubMed1996

Transperineal biopsy leads to the diagnosis of genitourinary neurofibromatosis in association with a congenital malformation of the urinary tract.

OBJECTIVE: A case of genitourinary fibromatosis with associated anomalies is presented. METHODS: Clinical evaluation included ultrasonography, urography, CT scan and MR image. Ultrasonography-guided perineal biopsy was performed with a 14-gauge Tru-cut needle. RESULTS: Rectal examination revealed a very hard prostatic mass in the 22-year-old patient. The histological result and clinical data indicated the diagnosis of genitourinary von Recklinghausen disease. CONCLUSION: We report a very rare case of genitourinary neurofibromatosis associated with congenital anomalies of the urinary tract. The diagnosis was obtained with US-guided transperineal biopsy.

Adult↗
PubMed1996

Small hepatocellular carcinoma. Detection with US, CT, MR imaging, DSA, and Lipiodol-CT.

Twenty-two patients with 37 small (3 cm or less) nodular lesions of hepatocellular carcinoma (HCC) were examined with ultrasonography (US), CT, MR imaging, digital subtraction angiography (DSA), and CT following intraarterial injection of Lipiodol (Lipiodol-CT). All patients subsequently underwent surgery, and the gold standard was provided by intraoperative US. The detection rate was 70% for US, 65% for CT, 62% for MR imaging, 73% for DSA, and 86% for Lipiodol-CT. A significant difference (p < 0.05) was observed between the detection rate of Lipiodol-CT and the detection rates of all the other imaging modalities. The difference was even more manifest (p < 0.02) when only lesions smaller than or equal to 1 cm were considered. It is concluded that Lipiodol-CT is the single most sensitive examination to detect small nodules of HCC. It should therefore be considered a mandatory step in the preoperative evaluation of patients with HCC considered to be surgical candidates after noninvasive imaging studies.

Aged↗
PubMed1996

Comparison among sonography, double-tracer subtraction scintigraphy, and double-phase scintigraphy in the detection of parathyroid lesions.

OBJECTIVE: This study prospectively evaluated the sensitivity of high-resolution sonography compared with double-tracer 201Tl-99mTc scintigraphy (Tl-Tc) subtractive scintigraphy and double-phase 99mTc-sestamibi (Tc-MIBI) scintigraphy prior to surgery in the assessment of patients with primary hyperparathyroidism in a geographic region where areas of endemic thyroid goiter are present. SUBJECTS AND METHODS: Sonography and scintigraphy were used as first-step imaging procedures in 73 patients with primary hyperparathyroidism. In 30 (41%) of 73 cases, we found an association with a thyroid abnormality. We compared sonography with double-tracer Tl-Tc scintigraphy in 41 cases, with Tc-MIBI scintigraphy in 22 other cases, and with both scintigraphic studies in 10 other cases. RESULTS: Surgery demonstrated 68 solitary parathyroid lesions (66 adenomas, one hyperplasia, and one carcinoma), two adenomas in two patients, and multiple hyperplastic glands in two patients for a total of seven lesions. In one case no abnormal parathyroid gland was found. Overall sensitivity of sonography, Tl-Tc, and Tc-MIBI scintigraphy was 85%, 62%, and 82%, respectively. In patients with concomitant thyroid disease, the sensitivity of sonography, dual-tracer Tl-Tc, and Tc-MIBI was 77%, 67%, and 80%, respectively. CONCLUSION: Our study proves that sonography and scintigraphy are equally able to detect parathyroid lesions before surgery in patients with concomitant thyroid diseases. In patients without thyroid abnormalities, detection rates of sonography and Tc-MIBI do not show any statistical difference, and the detection rate of Tl-Tc is significantly inferior to that of sonography. Sonography alone should be used as the first step for localization of abnormal parathyroid glands prior to surgery, and Tc-MIBI scintigraphy should be used as the second step when sonography is negative.

Adolescent↗
PubMed1996

[Implementation of a server World Wide Web of radiology accessible by Internet].

Internet is an international computer network that uses standard communication protocols for the exchange of information. This facilitates the retrieval of multimedia data through a "web" of servers distributed in the whole world. Among Internet users, Radiologists are a potentially important segment, due to the inherent multimedia characteristics of the discipline, which requires a continuous international update of information. The Department of Radiology of the University of Pisa has an Internet access through the metropolitan area network which was installed in the framework of the CNR Telecomunicazioni Project. The Internet access allowed the implementation of a World Wide Web server made public on Internet in March, 1994, being the first European server specifically oriented to radiology. This server can be accessed at the following address: http:@www.rad.unipi.it:7080/IRMosaicHome.html . On the server, 3 hypermedia papers are present, a list of international servers containing radiological information, a questionnaire, and statistics concerning the number of users who accessed the server. In the first 18 months of public access through Internet (April 1, 1994-September 30, 1995) 16,166 users accessed the server, retrieving 127,349 documents, corresponding to 1,279.7 MByte of information. The mean amount of information retrieved in each access to the server in the considered quarters ranges from 72 to 85.8 kByte. The geographic distribution of the users who accessed the server is the following: United States, 7,158, Italy, 2,466; other European countries, 3,813; other extra-European countries, 2,729. The increasingly diffuse knowledge of Internet services had a substantial impact on the rise in number of the servers and of the users who can access them. It is likely that in the future this technology will be used with increasing interest by Radiologists, since it provides easier "navigation" through multimedia information, consisting of text and several images, without the inherent limitations of the printed paper.

Computer Communication Networks↗
PubMed1995

Treatment of small hepatocellular carcinoma with percutaneous ethanol injection. Analysis of prognostic factors in 105 Western patients.

BACKGROUND: Percutaneous ethanol injection (PEI) has been used in the Far East for treating small, unresectable hepatocellular carcinoma (HCC). To clarify when treatment with PEI may be best indicated for Western patients with HCC, the authors performed a retrospective analysis of the clinicopathologic factors influencing prognosis. METHODS: From December 1987 to August 1994, 105 patients with cirrhosis with HCC received PEI as the sole anticancer treatment. Eighty-two patients had uninodular tumors smaller than 5 cm, and 23 patients had multiple lesions (2-4) smaller than or equal to 3 cm each. All patients were in Child-Pugh class A (n = 64) or B (n = 41). Survival was analyzed according to patient- and tumor-related factors by means of the Kaplan-Meier method. RESULTS: The estimated survival rates of all 105 patients were 96% at 1 year, 86% at 2 years, 68% at 3 years, 51% at 4 years, 32% at 5 years, and 24% at 6 years. Survival was not affected by sex, age, etiology of cirrhosis, or hepatitis B surface antigen or anti-hepatitis C virus positivity, but depended on Child-Pugh class (P = 0.006) and presence of ascites (P = 0.009). Patients with a pretreatment alpha-fetoprotein level of 200 ng/ml or less had a better prognosis than patients with an alpha-fetoprotein level higher than 200 ng/ml (P = 0.007). Patients with unmodular HCC of 3 cm or less had significantly better long term survival (P = 0.04) than patients with uninodular HCC of 3.1-5 cm or with multinodular tumors. Tumor grade according to Edmondson and Steiner and tumor volume, in contrast, did not significantly influence prognosis (P > 0.1). CONCLUSIONS: For Western patients with HCC treated with PEI, the prognosis was highly dependent on the severity of the underlying cirrhosis. Treatment with PEI is best indicated for patients with uninodular tumors of 3 cm or less in greatest dimension and an alpha-fetoprotein level lower than 200 ng/ml.

Administration, Cutaneous↗
PubMed1995

Hepatocellular carcinoma: use of color Doppler US to evaluate response to treatment with percutaneous ethanol injection.

PURPOSE: To determine the usefulness of color Doppler ultrasound (US) in the evaluation of the response of hepatocellular carcinoma (HCC) to percutaneous ethanol injection (PEI). MATERIALS AND METHODS: Forty-one patients with 48 lesions 2-5 cm in diameter underwent color Doppler US before and after PEI. Computed tomography (CT), magnetic resonance (MR) imaging, and percutaneous biopsy were also performed to help establish the outcome of therapy. RESULTS: Before treatment, color signals with an arterial Doppler spectrum were seen in 44 of 48 lesions with a frequency shift of 0.51-4.11 kHz (mean, 1.65 kHz). After PEI, 37 of these lesions showed no color signal and were found to be necrotic at CT, MR imaging, and biopsy. In six of seven lesions containing residual tumor, pulsatile flow was still identified, although the frequency shift was significantly decreased (P = .01). CONCLUSION: Color Doppler US proved useful in the assessment of the therapeutic effect of PEI on HCC.

Aged↗
PubMed1995

Treatment of large HCC: transcatheter arterial chemoembolization combined with percutaneous ethanol injection versus repeated transcatheter arterial chemoembolization.

PURPOSE: To compare the efficacy of transcatheter arterial chemoembolization (TACE) combined with percutaneous ethanol injection (PEI) versus repeated TACE in the treatment of large hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty-three patients with cirrhosis and a large HCC (main tumor, 3.1-8.0 cm in diameter with no more than two daughter nodules) were enrolled in a prospective, randomized study. Twenty-six patients underwent a single TACE session followed by PEI (TACE-PEI group), whereas 27 patients underwent two to five TACE sessions (TACE group). Both groups of patients were similar with regard to liver function. Follow-up ranged from 8 to 39 months. RESULTS: Complete therapeutic responses were higher (P < .05) and tumor recurrences during follow-up were lower (P < .05) in the TACE-PEI group than in the TACE group. Patients in the TACE-PEI group survived longer than those in the TACE group, although the difference was not significant (P > .1). The rates of survival without recurrence were better in the TACE-PEI group than in the TACE group (P < .05). CONCLUSION: Use of a single TACE session combined with PEI is more effective than repeated TACE in the treatment of large HCC.

Aged↗
PubMed1995

Portal vein thrombosis after percutaneous ethanol injection for hepatocellular carcinoma: value of color Doppler sonography in distinguishing chemical and tumor thrombi.

OBJECTIVE: The distinction between benign (chemical) and tumor thromboses of the portal vein after treat,ent with percutaneous injection of ethanol for hepatocellular carcinoma is crucial for the proper management of the patient. The purpose of this study was to determine whether color Doppler sonography can be used to differentiate between the two types of thrombi. SUBJECTS AND METHODS: Between October 1991 and April 1994, portal vein thrombosis was detected by color Doppler sonography in 19 patients (13 men and six women 59-77 years old; mean age, 67 years) who had hepatocellular carcinomas and who had received percutaneous ethanol injection (n = 11) or percutaneous ethanol injection after transcatheter arterial embolization (n = 8). The criterion for diagnosing tumor thrombosis by color Doppler sonography was the detection of pulsatile arterial flow in the thrombus. The benign or malignant nature of the thrombosis was subsequently established by percutaneous fine-needle biopsy of the thrombus; malignant thrombosis was seen in 13 patients, and chemical thrombosis was seen in six patients. RESULTS: Pulsatile arterial flow in the thrombus was observed by color Doppler sonography in 12 of the 13 malignant thrombi and in none of the bland thrombi. The flow was hepatopetal in seven cases and hepatofugal in five cases. The peak systolic frequency shift ranged from 0.59 to 2.65 kHz (mean, 1.35 kHz), and the resistive index ranged from 0.37 to 0.69 (mean, 0.55). The sensitivity and the specificity of color Doppler sonography for the detection of tumor thrombosis were 92% and 100%, respectively. CONCLUSION: Our study shows that color Doppler sonography is a reliable way to differentiate between chemical and tumor thromboses of the portal vein in patients with hepatocellular carcinomas treated by ethanol injection. When the sonogram shows pulsatile arterial flow within the thrombus, percutaneous biopsy of the thrombus is unnecessary. The finding is always indicative of malignant thrombosis.

Aged↗
PubMed1995

[Preoperative imaging in the detection of parathyroid tumefaction in patients with primary hyperparathyroidism. The authors' own experience].

The authors report their 3-year experience with the diagnosis of parathyroid lesions in primary hyperparathyroidism patients in a geographic area where the occurrence of endemic goiter is medium. Our study was aimed at prospectively assessing preoperative imaging results in these patients. The following imaging methods were used: high-definition and color-Doppler ultrasonography (US), double-tracer 201Thallium-99mTechnetium (T1/Tc) subtraction scintigraphy, Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and US-guided fine-needle aspiration of the suspected parathyroid lesions. Preoperative US and scintigraphy were performed in 50 patients with primary hyperparathyroidism; in addition, color-Doppler US studies were performed in 33 patients for vascular characterization of the lesions. In 19 patients, the suspected lesions were punctured under US guidance to measure parathormone (PTHa) and thyroglobulin (TGa) levels in the aspirated material. CT and MRI were performed in 9 patients, to identify a possible ectopic parathyroid gland. Surgery demonstrated 48 solitary parathyroid lesions and one double parathyroid adenoma. In one patient no abnormal parathyroid gland was found. Overall sensitivity rates of US and scintigraphy were 85.7% and 61.2%, respectively. In multinodular goiter patients, the sensitivity rates of US and scintigraphy were 71.4% and 47.6%, respectively. At color-Doppler US the presence of parenchymal vascularization was specific of parathyroid nodules and the method helped differentiate parathyroid lesions from thyroid nodules in 14 multinodular goiter patients. Overall PTHa sensitivity was 72.2% and its specificity 100%. Overall TGa sensitivity was 100% and specificity 94.7%. CT and MRI allowed the detection of 8 ectopic parathyroid lesions. In conclusion, in our personal experience, US should be preferred to double-tracer T1/Tc subtraction scintigraphy in the early examination of primary hyperparathyroidism patients. When US detects a suspected parathyroid lesion, color-Doppler US and PTH and TG sampling can make useful diagnostic tools for reducing false-positive results, especially when thyroid disease is associated.

Adolescent↗
PubMed1994

Hepatocellular carcinoma: CT and MR features after transcatheter arterial embolization and percutaneous ethanol injection.

PURPOSE: To investigate the reliability of computed tomography (CT) and magnetic resonance (MR) imaging in the evaluation of the response of hepatocellular carcinoma (HCC) to transcatheter arterial embolization (TAE) followed by percutaneous ethanol injection (PEI). MATERIAL AND METHODS: Between January 1991 and November 1992, 20 patients (15 men and five women, aged 53-73 years [mean, 64.6 years]) with 31 HCC lesions underwent CT and MR imaging before and after treatment with combined TAE and PEI. RESULTS: Twenty-seven tumors, which were hypointense on post-treatment T2-weighted images and on gadolinium-enhanced T1-weighted images, were seen to be necrotic at biopsy. In four cases of incomplete necrosis, viable tumor was hyperintense on T2-weighted images and was enhanced after administration of contrast material. CT provided a larger spectrum of imaging features as a result of the presence of both hyperattenuating areas (caused by retention of iodized oil) and hypoattenuating areas (due to ethanol-induced necrosis). CONCLUSION: CT and MR imaging findings proved useful in the evaluation of the response of HCC to combined TAE and PEI.

Aged↗
PubMed1994

Treatment of hepatocellular carcinoma with percutaneous ethanol injection: evaluation with contrast-enhanced MR imaging.

OBJECTIVE: The aim of this study was to investigate the usefulness of unenhanced and enhanced MR imaging in evaluating the response of hepatocellular carcinoma to percutaneous injection of ethanol. SUBJECTS AND METHODS: Thirty-one patients with 40 hepatocellular carcinomas less than 5 cm in diameter were examined with MR imaging before and after percutaneous injection of ethanol. Unenhanced T1- and T2-weighted and contrast-enhanced T1-weighted spin-echo images were obtained. CT and percutaneous biopsy were performed 1 month after the final injection of ethanol and repeated at 6-month intervals to establish the outcome of treatment: complete tumor necrosis was shown in 36 lesions and incomplete tumor necrosis was seen in four lesions. RESULTS: Of the 36 proved necrotic lesions, 31 showed homogeneously low signal intensity on T2-weighted MR images obtained after treatment, owing to coagulative necrosis of the tumor. In the remaining five necrotic lesions, hypointense and hyperintense areas coexisted; the hyperintense areas were caused by liquefactive necrotic material in two cases and by chronic inflammatory tissue along the boundary of the necrotic area in three cases. None of the 36 necrotic lesions showed contrast enhancement on T1-weighted images obtained after IV injection of gadopentetate dimeglumine. In the four lesions with incomplete necrosis, the viable portion of the tumor was identified as a hyperintense area on T2-weighted images and as an enhancing area on contrast-enhanced T1-weighted images. No correlation was found between lesion features on unenhanced T1-weighted images and outcome of therapy. CONCLUSION: Contrast-enhanced T1-weighted MR images allow a reliable evaluation of the effectiveness of treatment and are more accurate than unenhanced MR studies. Contrast-enhanced MR imaging may be considered a valuable alternative to contrast-enhanced CT in the follow-up of hepatocellular carcinomas treated with percutaneous injection of ethanol.

Aged↗
PubMed1994

[A proposal for the use of tridimensional reconstruction in oncology to better assess tumor stage and response to therapy].

Besides radiation therapy, diagnostic imaging has always been considered the main medical application of three-dimensional (3D) reconstruction. On the contrary, our study focused mainly on the use of 3D reconstruction for both spatial characterization and morphometric evaluation of the reconstructed objects. We aimed at assisting physicians to solve clinical and therapeutic problems. In particular, in oncology, 3D reconstruction may allow the objective and accurate quantification of the volume of neoplastic lesions. Therefore, we decided to focus our attention on the spatial characterization and morphometric assessment of the examined neoplastic masses. Volumetric measurements based on 3D reconstruction may be of great value to assess volume changes after irradiation and/or chemotherapy of neoplastic lesions. This might also allow to compare, on the basis of such changes, the role of different treatment protocols on similar neoplastic lesions and, possibly, to lead to a new TNM staging system no longer based on 2D measurements but on volumes. To meet these clinical requirements, we developed a software system for accurate volume measurements. We believed 3D reconstruction to be suited to this purpose and therefore we implemented a software incorporating 3D reconstruction capabilities of abnormal anatomical structures from 2D images, the rotation of the volume of interest for better assessment of spatial relationships, and finally morphometric evaluation, for accurate volume measurements. Instead of calculating the volume of a neoplastic lesion by means of a 3D reconstruction algorithm considering voxels as indivisible (voxel-based approach), we implemented a surface rendering algorithm using a cell-based approach, because it allowed voxels to be represented as small volume units, which could be further divided by means of linear interpolation. Thus, great flexibility was possible in the determination of surfaces, together with a good approximation of the volume of the neoplastic lesions. To assess the reliability of the developed software system, we used a real phantom. Its known actual volume was compared with the one measured by our system and the difference, expressed as a percentage of the actual volume itself, was compared with the one obtained by using reconstruction algorithms with a voxel-based approach (1.4% vs 4.4%). The error produced by the latter is three times greater than the one produced by our algorithm. This is a major result for the physician: better approximation of the actual volume of a neoplastic lesion means better evaluation of the number of neoplastic cells in the lesion. This may be useful for the clinical management of the patient. In the paper, the first clinical applications of our algorithm are reported.

Algorithms↗