1,720,961 research outputs found
[Computerized tomography in the evaluation of the larynx after surgical treatment and irradiation].
No full textThe follow-up of the patients submitted to surgery for laryngeal carcinoma requires both clinical and CT examinations, particularly in the cases at high risk of recurrence. Our series consisted of 72 laryngeal carcinoma patients operated on and regularly followed-up with CT to distinguish relapse from normal or abnormal postoperative changes. Seventy-two laryngeal carcinoma patients were submitted to surgery: total laryngectomy was performed in 33 cases, supraglottic laryngectomy in 16 cases, Labayle subtotal laryngectomy in 18 cases and Mayer Piquet subtotal laryngectomy in 5 cases. The patients were followed-up postoperatively with CT and 94 examinations were performed in all; pathology was performed in all the cases with radiologic suspicion of recurrence (19 patients) and further clinical examinations were performed to exclude recurrence in the 14 cases where imaging findings were questionable. Local recurrences were confirmed in 16 of 19 patients with positive CT findings. Radiologically, the recurrence appeared as an irregular thickening of the pharyngo-laryngeal wall with inhomogeneous density after i.v. contrast agent infusion. The patients submitted to total or supraglottic laryngectomy recurred most often at the cranial site of resection (5/6 cases), those submitted to Labayle surgery at the mucosa adjacent to the cricoarytenoid unit (3/3 cases) and those submitted to Mayer Piquet surgery in the supraglottic region. Two more patients submitted to emergency tracheotomy recurred at this level. Lymph node recurrences were found in 6 total laryngectomy patients. Misinterpretations were most frequently due to postirradiation changes (5 of 14 cases) or to atypical postoperative images (4/14 cases). Three more patients presented a secondary lesion misinterpreted as a relapse. Our results confirm the role of CT in the follow-up of the patients operated on for laryngeal carcinoma when CT findings are closely correlated with clinical and endoscopic results, permitting to correctly assess the extent of relapse and possible nodal spread
Long-term results of 60 patients with pathologic stage I & IIA Hodgkin's disease treated with exclusive mantle radiation therapy
No full textBetween January 1972 and December 1982 60 patients with pathological stage IA and IIA Hodgkin's disease (HD) were submitted to Mantle irradiation only. Twenty-five were in stage I (32.1%) and 35 in stage II (67.9%). All patients were submitted to staging laparotomy. Cases with large mediastinal mass were excluded from this series. Delivered doses were 44 Gy in involved areas, 40 Gy on the mediastinum and 36 Gy on uninvolved sites. Twenty-four patients in stage I (96%) and 33 in stage II (94.2%) obtained complete remission. Actuarial 10- and 20-yr overall (OS) rates were 86% and 79.1%, respectively. Event-free (EFS) and relapse-free (RFS) survival rates at 10 and 20 yr were 67.5% and 62.1%, respectively. The occurrence of disease relapse resulted in the only statistical significant prognostic factor for OS in both univariate and multivariate analysis. Distant and extranodal recurrences were significantly (P<0.01) related to a reduced OS. On multivariate analysis stage was the only determinant factor for increased RFS. Extended field RT proved to be an effective curative modality for stage I HD patients, whereas 15 out of 33 patients in stage II relapsed requiring salvage therapy. Long-term analysis of survival and treatment-related morbidity rates will improve our knowledge and assist the physicians to choose the therapeutic option to offer to HD patients
[Radiotherapy of bone tumors. Analysis of a historic series and review of the literature].
No full textThe authors report a series of patients with osteosarcoma or Ewing's sarcoma irradiated 1968-1988 at the Institute of Radiology of "La Sapienza" University, Rome. Twelve of 17 osteosarcoma patients (71%) died and 5 are alive, with a median survival of 13 months. Seven of 12 Ewing's sarcoma patients (58%) died and 5 are alive (42%), with a median survival of 67 months. These results are similar to those of most contemporary series in the literature; the long follow-up of our series allowed us to calculate actuarial survival rates at 5, 10 and 15 years of 41%, 34% and 17%, respectively, in osteosarcoma patients and 75%, 45% and 34% for those with Ewing's sarcoma. The review of the literature on the management of bone tumors high-lights the importance of new developments and technologies to improve the life expectancy of these patients. The authors discuss the role of modern imaging techniques in defining tumor margins and predicting treatment-induced tumor regression and the research into new therapeutic approaches. Multimodality combinations and new schedules appear promising tools to improve prognosis and to reduce side-effects, thus stressing the need of combined efforts of surgeons, radiotherapists and chemotherapists. State-of-the-art radiotherapy can further increase local control with higher total doses to the lesion and selectively sparing adjacent normal tissues, thanks to 3D treatment planning of hadron beam equipment
[Long-term survival of patients with inoperable hepatocarcinoma, treated with interventional radiology].
No full textSurvival rates in untreated patients with unresectable HCC are rather disappointing. Our study was aimed at assessing long-term survival in the patients submitted to combined transarterial chemoembolization (TACE) and percutaneous ethanol injection (PEI). We treated 223 patients, but long-term follow-up is available in 143 of them only. Eighty-seven of 143 patients had Child's A liver cirrhosis, 45 had Child's B and 6 Child's C. Five patients did not have cirrhosis. Eighty-seven patients had single lesions--45 of them 5 cm. Fifty-six patients had multiple/diffuse lesions. All patients underwent TACE while PEI was performed in selected patients with single or double lesions. Survival rates were calculated with the life-table analysis by Kaplan and Meyer. Follow-up was 1-72 months (median: 28 months). At 1, 3 and 5 years, the overall survival rates were 72%, 34.5% and 16.4%, respectively. The survival rates at 1, 3 and 5 years in single lesions 5 cm and 58.8%, 12.5% and 0% in multiple/diffuse lesions. In conclusion, the long-term results of the radiologic treatment of unresectable HCC are comparable with surgical results obtained in selected cases
[Assessment of complications in patients with lung transplantation with high resolution computerized tomography].
No full textHigh Resolution Computed Tomography (HRCT) has been used by many authors to study the early complications of lung transplantation. Bronchoscopy, transbronchial biopsy and the clinical parameters are the tools of choice to diagnose such complications; HRCT showed excellent sensitivity (100\%) and good specificity (93\%) especially in detecting bronchial stenoses. We report the preliminary results of HRCT in detecting early/late complications in lung transplant recipients.Sixteen lung transplant recipients (5 single and 11 double transplants) were examined with HRCT at the Servizio Speciale Diagnostica V of "La Sapienza" University (Rome, Italy). The CT findings were compared with the results of bronchoscopy and respiratory function tests. The patients (8 men and 8 women; age range: 18-57 years, mean: 37.5) had cystic fibrosis (9), emphysema (3), alpha-1-antitrypsin deficiency (1), idiopathic pulmonary fibrosis (2), and bronchiectasis (1).During the follow-up, one patient died of pulmonary edema. CT findings were normal in 3 patients and mild pleural effusion was seen in 2. The other HRCT findings were: bronchial stenosis in 5 cases (which was bilateral in 1) and bronchial dehiscence in 1 patient; four cases of infection (1 CMV, 1 aspecific bacterial pneumonia, 1 Chlamydia psittacea and 1 Aspergillosis) and one of brochiolitis obliterans. A patient was treated for acute and one for chronic rejection. A CMV infection involved only the native lung in a patient. CT is easy to perform and a repeatable and well-tolerated tool with high sensitivity (100\%) and good specificity (93\%) in the early diagnosis of complications, particularly bronchial stenoses, which complications are often missed at bronchoscopy or clinically silent. CT should be always performed before bronchoscopy because it can provide valuable information for bronchoscopy targeting.In agreement with other authors we consider HRCT a very useful tool in the early diagnosis of the complications following lung transplantation
[The solitary pulmonary nodule: the preliminary results in differential diagnosis by high-resolution computed tomography with a contrast medium].
No full textHigh-resolution computed tomography (HRCT) with iodinated contrast material has been used by many authors to study solitary pulmonary nodules (SPNs). The degree of enhancement was correlated with the nodule malignancy.Forty adult patients were examined, before and after contrast agent administration, with incremental dynamic CT. We selected 22 patients with SPNs (3-30 mm phi, except one with 40 mm phi). The CT numbers of the inner nodule were calculated before and 1, 2 and 3 minutes after the i.v. administration of a weight-related dose (1.5 mL/kg/min) of nonionic iodinated contrast agent. A dose of 100 mL contrast agent was used in the first 6 patients. The difference in CT numbers between unenhanced images and the images with maximum enhancement (max. attenuation) was also calculated.Histologic diagnoses included 4 tuberculomas, 3 hamartomas and 15 malignant tumors (9 adenocarcinomas, 5 squamous cell carcinomas and 1 non-Hodgkin lymphoma). The CT numbers (in Hounsfield units, HU) of malignant nodules ranged 12-31 HU (mean: 21.5 HU) before contrast agent administration; the "long-standing" tuberculomas ranged 11-22 HU (mean: 16.5 HU) and the hamartomas had a mean density of 10.5 HU. We excluded for the study two "fresh" tuberculomas, one of which was surrounded by a low-attenuation infiltrate (the halo sign). We selected a threshold value of 20 HU on enhanced CT images to distinguish malignant (> or = 20 HU) from benign (< or = 20 HU) nodules. All lung cancers had complete enhancement (mean density: 35.5 HU). With 20 HU as the threshold value for a positive test, sensitivity was 100\%, specificity 85.7\%, positive predictive value 93.8\% and negative predictive value 100\%; test bias was 1.067.Positron emission tomography (PET) with 2-[fluorine-18] fluoro-2-deoxy-D glucose is reported to be as accurate as enhanced HRCT, but it does not provide accurate morphological information, is not widely available and it is quite expensive: therefore, in our opinion, CT should be preferred. After examining over 100 patients, we may use our results in the decision analysis comparing surgical risk with cancer risk
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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