Search PubMed⌕ Search

Biomedical subjects

M Gaeta

Publications and source records attributed to M Gaeta.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Magnetic resonance pyelography: clinical use of ultrafast breath-hold sequences in obstructive uropathy. Personal experience].

INTRODUCTION: We investigated the diagnostic yield of MR pyelography (MRP) performed with two ultrafast breath-hold sequences in obstructive uropathy patients. MATERIAL AND METHODS: Thirty-four patients with US demonstration of urinary tract dilation were examined with MRP at 1.5 T and with a standard body coil. HASTE sequences (TE 66, ETL 128, FA 180 degrees, 1 NEX, MA 240 x 256, slice thickness 4 mm, TA 13 s) were always performed and 26/34 patients were also examined with single-shot TSE sequences (TE 1100, ETL 240, FA 150 degrees, 1 NEX, slice thickness 7 cm, MA 240 x 256, FS, TA 7 s); 20/34 patients were given 500 mL superparamagnetic contrast agent (Lumirem). MRP findings were interpreted independently by two radiologists and analyzed for image quality, the presence/absence of dilation, the obstruction grade (mild, moderate, severe), site (intrarenal; ureteropelvic junction; proximal, mid-, distal ureter; indeterminate) and cause (intrinsic obstruction from a stone or other conditions; stenosis; indeterminate cause). The sensitivity, specificity, positive and negative predictive values for the detection of urinary tract dilation were calculated for each reviewer and interobserver agreement was calculated with the k analysis relative to the presence, grade, site and cause of urinary tract dilation. RESULTS: MRP examinations were considered technically adequate in all cases by both observers. As for the presence of urinary tract dilation, the values were 100% for the first observer and 97%, 100%, 100%, and 95%, respectively, for the second observer. Interobserver agreement was .98 for dilation presence (excellent), .80 for dilation degree (excellent), .62 for dilation site (good) and finally .69 for dilation cause (good). DISCUSSION AND CONCLUSIONS: MRP performed with the ultrafast breath-hold technique provides very good results in diagnosing urinary tract dilation, as well as the obstruction grade, site and cause, with results equal or even superior to those of non-breath-hold sequences. Ultrafast MRP lasts only 10 minutes, meaning it occupies the magnet shortly and costs less: it can be thus considered a routine alternative to conventional diagnostic imaging, especially ivp, in the evaluation of obstructive uropathy.

Humans↗
PubMed1997

Transudative vs exudative pleural effusions: differentiation using Gd-DTPA-enhanced MRI.

The aim of this study was to investigate the capability of Gd-DTPA-enhanced MRI to differentiate between exudative and transudative pleural effusions. An MRI examination was performed on 22 patients with different types of pleural effusion (10 transudative and 12 exudative effusions). T1-weighted SE images were obtained before and 20 min after administration of Gd-DTPA (0.1 mmol/kg). The degree of enhancement of pleural effusions was evaluated both by visual assessment and by quantitative analysis of images. None of 10 transudative effusions showed significative enhancement, whereas 10 of 12 exudative effusions showed enhancement (sensitivity 83 %, specificity 100 %, positive predictive value 100 %). The postcontrast signal intensity ratios (SIRs) of exudates were significantly higher than corresponding precontrast ratios (P = 0. 0109) and the postcontrast SIRs of exudates were significantly higher than those of transudates (P = 0.0300). Exudative pleural effusions show a significant enhancement following administration of Gd-DTPA. We presume that this may be caused by increased pleural permeability and more rapid passage of a large amount of Gd-DTPA from the blood into the pleural fluid in case of exudative effusions. In our limited group of patients, signal enhancement proved the presence of an exudative effusion. Absence of signal enhancement suggests a transudate, but does not exclude an exudate.

Contrast Media↗
PubMed1997

The role of the ostiomeatal unit anatomic variations in inflammatory disease of the maxillary sinuses.

OBJECTIVE: The purpose of the study was to determine the correlation between bony anatomic variations of the ostiomeatal unit (OMU) and chronic maxillary sinusitis. The study was based on the hypothesis that the mucosal contact caused by the variations represents the critical factor in increasing the risk of maxillary sinusitis. MATERIALS AND METHODS: Thin section high resolution computerised tomography (CT) examinations of the paranasal sinuses in 73 consecutive patients with 113 anatomic variations of the OMU were retrospectively reviewed. The following CT features were assessed: (1) Type of anatomic variations, (2) presence of a mucosal contact in the OMU and (3) presence of maxillary disease. Statistical evaluation was carried out using chi 2-test. RESULTS: The following bony anatomic variations were found: Concha bullosa (67 cases), abnormalities of the uncinate process (18 cases), Haller's cells (24 cases) and large ethmoidal bulla (four cases). Only 52 of the 113 anatomic variations were associated with ipsilateral maxillary disease (mucosal thickening, mucous retention cysts, polyps, retained secretions). Of 113 variations, 44 caused a mucosal contact, 35 of these were associated with maxillary abnormalities, while in nine cases there were no pathologic changes. Of 69 variations, 17 did not cause mucosal contact (P < 0.05). CONCLUSION: Our data shows that, in the presence of anatomic bony variations, a contact between the mucosal surface of the OMU is valuable in predicting the likelihood of a maxillary inflammatory disease.

Adolescent↗
PubMed1997

[Contrast-enhanced study of solitary pulmonary nodules with thin-section computed tomography].

INTRODUCTION: Since many benign and malignant pathologic conditions can appear as solitary pulmonary nodules, to establish nodule nature is always necessary for correct patient management. Recently, some authors have demonstrated the effectiveness of incremental dynamic CT in distinguishing cancerous from noncancerous lesions. The purpose of this work is to report our personal experience in this field. MATERIAL AND METHODS: We reviewed the incremental dynamic CT scans of 21 patients with a solitary pulmonary nodule < 3.5 cm phi without any calcifications, cavities and fat--namely, 15 carcinomas, 3 granulomas, 2 hamartomas, 1 abscess. Lesion density was evaluated before and 30 s, 1, 2, 3 and 5 min after contrast agent administration; we used a circular region of interest consisting of the central portion of the nodule in all cases and of 60-70% of its area in most cases. We subdivided the nodules into two groups, according to their enhancement: the nodules with > 20 HU and those with < 20 HU. All the lesions were submitted to surgery and histologic studies. RESULTS: Fourteen of 15 carcinomas and one hamartoma had contrast enhancement > 20 HU; an abscess exhibited marked ring-shaped contrast enhancement (positive predictive value: 87%). One carcinoma, three granulomas and one hamartoma had no contrast enhancement, or else it was < 20 HU (negative predictive value: 80%). DISCUSSION: Recently, some authors have demonstrated that malignant nodules, studied with incremental dynamic CT, have higher contrast enhancement than benign nodules. A value > 20 HU is a good predictor of malignancy (positive predictive value: 90%) and, conversely, a value < 20 HU is an unquestionable sign of benignity (negative predictive value: 100%). Our findings confirm the positive predictive value of enhancement > 20 HU, but not its negative predictive value because we found a malignant nodule without contrast enhancement. CONCLUSIONS: Incremental dynamic CT is an effective indicator of solitary pulmonary nodule nature, but its predictive value is not absolute and therefore this technique should be integrated with biopsy in the cases which are clinically or radiologically suspicious.

Contrast Media↗
PubMed1996

Report of an intrapulmonary solitary fibrous tumor: fine-needle aspiration cytologic findings, clinicopathological, and immunohistochemical features.

The authors describe a rare case of intrapulmonary solitary fibrous tumor (SFT). Morphologically, the tumor showed a disorganized or "patternless" arrangement of plump to spindle cells in a collagenous stroma. Tumor cells were immunoreactive for vimentin, but not for keratin, carcinoembryonic antigen, epithelial membrane antigen, factor-VIII related antigen, S-100 protein, desmin, and actin. These immunohistochemical findings suggested fibroblastic differentiation, in keeping with the putative submesothelial origin of the tumor. The problems concerning the fine-needle aspiration (FNA) preoperative diagnosis of SFT are briefly discussed.

Aged↗
PubMed1996

[The angiogram sign in lung consolidation: what is its diagnostic value?].

The angiogram sign in chest CT is the demonstration of normally enhanced pulmonary branches within hypoattenuating lung parenchyma consolidation. In a retrospective review of the chest CT exams performed in a 2-year period, we identified the angiogram sign in 10 patients with lung consolidation; the diagnosis was central lung tumor with obstructive pneumonia in 4 patients, bronchioloalveolar carcinoma in 2 patients, postirradiation fibrosis in 1 patient, tuberculous pneumonia in 1 patient, lung lymphoma in 1 patient and metastasis from pancreatic tumor in 1 patient. The diagnosis was made with cytology and/or surgical specimen in 9 patients and with clinical-radiologic follow-up in 1 patient. The density, air and mucous bronchogram and the volume loss in the consolidated lung were also considered. The consolidated lung density was < 30 HU in 5 patients-one bronchioloalveolar carcinoma, one metastasis from pancreatic carcinoma and 3 obstructive pneumonia cases-, while it was > 30 HU in the extant 5 patients. The air bronchogram sign was observed in 4 cases-one bronchioloalveolar carcinoma, one metastasis, one postirradiation fibrosis and one lung lymphoma-, while a mucous bronchogram was observed in 3 patients with obstructive pneumonia. Lung volume was reduced only in 2 patients-one obstructive pneumonia and one postirradiation fibrosis. In our opinion, the CT angiogram sign must be considered a poorly specific sign, because it can be found in many pathologic processes, both benign and malignant. If associated with the other features of lung consolidation, the CT angiogram sign can help diagnose, together with clinical findings and the patient's history, the pathologic condition. Particularly, the angiogram sign within a hypoattenuated lung consolidation area can be found in obstructive pneumonia, while the angiogram sign within a hypoattenuated consolidation with an air bronchogram probably indicates a mucinous carcinoma with lipidic growth.

Angiography↗
PubMed1995

[Computerized tomography in the assessment of metastatic facial adenopathy].

The facial lymph nodes are classified in five groups: mandibular, buccinator, infraorbital, malar and retrozygomatic nodes. This paper reports the CT appearance of neoplastic involvement of these nodes, an unusual and not well documented event. The CT examinations of 62 patients with a history of primary or recurrent cancer of the epidermal structures of the face, oral cavity and sinonasal region were retrospectively reviewed to assess the presence of facial adenopathy. Nine cases of neoplastic involvement of facial nodes were found. Most commonly the buccinator nodes (4 cases) were involved, the infraorbital, mandibular (2 cases) and retrozygomatic nodes (1 case) being less commonly involved. No malar nodes were found. Neoplastic involvement of these nodes was caused by squamous cell carcinoma in 6 cases, by adenocarcinoma in 2 cases and by a lymphoma in 1 case. Normal nodes could not be confidently identified on CT studies. CT diagnosis of neoplastic involvement of facial nodes is based on the presence of a nodular lesion which lies along the lymphatic pathways of the primary neoplasm in an anatomically compatible location. CT diagnosis of facial nodes is very important for treatment planning if the nodes are deep or at a distance from primary cancer. This is especially true for retrozygomatic and buccinator nodes.

Facial Neoplasms↗
PubMed1995

[Computerized tomography in the assessment of obstructive jaundice caused by hepatic hydatid cysts].

This paper reports on the CT findings of obstructive jaundice caused by hydatid cysts of the liver, which are an unusual event occurring in 5-10% of cases. Thus, only a few reports can be found in the literature dealing with the CT features of this syndrome. Eight patients with obstructive jaundice were selected from 87 patients with hydatid disease of the liver and examined with CT. The CT diagnosis of rupture into the largest bile ducts is based upon the demonstration of hepatic hydatid cysts together with intrabiliary hydatid sand, membranes and scolices and/or the identification of parietal discontinuity with communication between the cyst and the biliary tree. Rupture into the largest bile ducts was demonstrated in 7 patients. The following CT patterns were observed: 1) intrahepatic biliary tract dilatation (all cases); 2) extrahepatic biliary tract dilatation (6 cases); 3) cyst wall interruption (5 cases--in 3 of them the communication between the cyst and the dilated bile duct was demonstrated); 4) daughter cysts, fragmented membranes or hydatid sand in the biliary tree (5 cases); 5) hydatid material in the gallbladder (1 case) and, finally, disappearance of the daughter cyst visible on a previous CT examination (1 case). In another patient, the diagnosis of compressive jaundice without biliary communication was suggested because a bulky hydatid cyst was found near the hilum of liver. CT findings were confirmed with ERCP or at surgery. CT failed to reveal small tears with minute biliary radicles, which are usually asymptomatic, whose diagnosis could be made only with preoperative cholangiography. Hydatid cysts of the liver can cause obstructive jaundice because of main bile duct compression or of large bile duct perforation with consequent passage of hydatid material into the biliary tree. This complication should be promptly managed surgically to avoid potentially fatal complications, which makes a preoperative diagnosis essential.

Adolescent↗
PubMed1994

[Antalgic radiotherapy in lumbosacral carcinomatous neuropathies].

Lumbosacral carcinomatous neuropathy (LCN) may be caused by infiltration or compression of the lumbosacral plexi and nerves from intrapelvic or paraaortic neoplasms. The authors submitted 23 patients complaining of LCN with CT documented intrapelvic or paraaortic tumors to palliative radiotherapy. Megavoltage external beam irradiation was administered using a 6-MV linear accelerator. Treatment field sizes ranged from 56 cm2 to 235 cm2 (mean: 150.54 cm2) and encompassed only the site where the disease involved the lumbosacral plexus or its branches. > or = 3 Gy/day fractions were used. Twenty-one of 22 assessable patients (95.4%) obtained LCN pain relief; 19 (86.3%) obtained complete LCN pain relief. The median time to pain progression (TPP) was 150 days (range: 39-510 days). The median survival was 165 days. Seven patients were LCN pain-free at death. Two patients are alive and LCN pain-free. The remaining 12 patients had recurrent LCN pain: four of them were reirradiated at the site of previous neuropathy and only two had partial relief again. The authors conclude that it is advisable to submit to palliative radiotherapy the inoperable disseminated and/or recurrent cancer patients complaining of LCN, to use large fractions not to occupy the extant time of their already short life-expectancy, and to design small fields to avoid acute side-effects.

Adult↗
PubMed1994

[Computerized tomography in gaseous hypotonic duodenography in the study of the pancreatico-duodenal area].

This study was aimed at assessing the role of CT-hypotonic gaseous duodenography in the study of the pancreatic-duodenal region. Forty-two patients with malignancies in this region were examined with CT of the upper abdomen followed by CT-hypotonic gaseous duodenography (30 pancreatic head cancers, 7 main bile duct and 5 ampullary lesions). In 20 of 28 cases of pancreatic head carcinoma, CT-hypotonic gaseous duodenography yielded more pieces of information than baseline abdominal CT and was also more useful in small pancreatic head cancers, < 4 cm diameter. In 4 of these patients, CT-hypotonic gaseous duodenography better demonstrated the pancreatic lesions which conventional CT had demonstrated poorly. In contrast, CT-hypotonic gaseous duodenography was less useful in main bile duct carcinomas, depicting focal duodenal infiltration in only 1 of 7 cases. In all ampullary tumor patients (5/5), CT-hypotonic gaseous duodenography demonstrated intraduodenal lesions. The authors conclude that CT-hypotonic gaseous duodenography is a useful technique to investigate small pancreatic head cancers and the method of choice to demonstrate ampullary lesions.

Adult↗