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1.
Acta Otolaryngol ; 121(4): 500-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11508512

RESUMO

Three-dimensional (3D) navigation systems are routinely used in the fields of endoscopic skull base surgery, neurosurgery, maxillo-facial and endoscopic sinus surgery. The use of such systems is associated with the following advantages: a better 3D orientation: a more confident surgeon; a more precise surgical approach; and a reduced operation time. Six different brands of 3D navigation system were compared in order to find out if there are major differences in performance and whether the considerable financial investment required to purchase such a system would be justified by a noticeable improvement in surgical interventions and a realization of the above expectations. The 3D navigation systems were tested by performing endoscopic sinus surgery on 26 patients suffering from chronic sinusitis. The system accuracy, the confidence of the surgeon, the time of anaesthesia, the cost, the number of personnel required (and their skills), and the technical resources were compared. No major differences in performance of the different brands of 3D navigation system were noticed. All of the systems showed high, but varying, system precision, the surgeons felt more confident and the time of anaesthesia was prolonged by 5-15 min. A well-trained operating staff is required. Assuming that the initial costs are excluded and that data transfer occurs automatically, personnel costs and the extra time required still have to be considered.


Assuntos
Sinusite/cirurgia , Cirurgia Assistida por Computador/instrumentação , Adulto , Doença Crônica , Endoscopia/métodos , Desenho de Equipamento , Feminino , Humanos , Masculino
2.
Radiology ; 220(2): 400-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11477243

RESUMO

PURPOSE: To calculate cutoff levels for quantitative ultrasonography (US) performed to distinguish healthy individuals and those with osteoporosis identified with dual x-ray absorptiometry. MATERIALS AND METHODS: In 1,357 patients (856 females, aged 55.1 years +/- 15.4 [mean +/- SD]; 501 males, aged 50.4 years +/- 15), bone mineral density measurements of the lumbar spine (posteroanterior, L1 through L4) and femoral neck were obtained, and quantitative US was performed to determine the stiffness of the calcaneus. Individuals with a T score less than -2.5 (osteoporotic) at the spine and femur were identified, and upper T-score cutoff values (3 SDs from the mean) in the groups of male and female patients with osteoporosis were identified. RESULTS: Females with dual x-ray absorptiometric values that were indicative of osteoporosis of the spine had an upper T-score cutoff value of -1.0 (males, -0.2). Females who had femoral osteoporosis showed an upper quantitative US T-score cutoff value of -0.6 (males, 0). CONCLUSION: Cutoff values may permit the use of quantitative US to screen for the presence of osteoporosis in the spine and femur. Quantitative US will help to prevent unnecessary dual x-ray absorptiometric and conventional radiographic examinations.


Assuntos
Calcâneo/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Colo do Fêmur , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Ultrassonografia
3.
Eur Arch Otorhinolaryngol ; 258(1): 38-41, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11271433

RESUMO

Three-dimensional navigation systems are routinely used in endoscopic skull base surgery, neurosurgery, maxillo-facial and endoscopic sinus surgery. Their precision can, however, change in the course of one experiment. We have compared five different 3D navigation systems and discuss here possible reasons for the limits of system precision. A plexiglass cube on which test points were marked served as a test-model. Two well-trained system users measured the distances between the test points in each of the five systems. The results were compared with reference data provided by the NUMEREX device at the Technical University of Vienna. The accuracy data shown by all these 3D navigation systems ranged from 0.0 mm to 6.67 mm. The accuracy data of a system calculated in advance did not always correspond with the system precision on the screen. The system precision in the center of the cube was higher than on its surface, which made us conclude that the angle between the tracker system and the pointing device touching the test point may be critical for system precision. Applying an automatic registration step did not result in greater system precision. Slice thickness and the angle of the pointing device seem to be responsible for system precision.


Assuntos
Instrumentos Cirúrgicos , Desenho de Equipamento , Humanos , Procedimentos Cirúrgicos Otorrinolaringológicos , Instrumentos Cirúrgicos/normas
4.
Parasitol Res ; 87(1): 7-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11199853

RESUMO

This study determined a profile of current Internet users in parasitology, their use patterns on the Internet for parasitologic purposes, and the Web sites they would recommend. In a European survey, 689 parasitologically engaged scientists were asked to fill out a questionnaire about Internet access, current problems, current and future use, and which Web sites they would recommend as well as about the use of e-mail. In all, 153 (22.2%) of the interviewees returned the questionnaire. Only one participant had no access to the Internet. Time expenditure was considered the main problem involved in use of the Internet. The Internet was mainly used for e-mail (96.1%); for literature research (93.5%); for reading of electronic journals (51.6%); and for gathering of information, e.g., about institutes and colleagues (58.2%) and about congresses (49.7%). In the future, 71.9% of the respondents would like to read electronic journals more often and 49.7% would like to use the web more intensively for acquisition of information about congresses, universities, and institutions. Requests for the future included an easier application of the browser software (33%) and a shorter response time (47.7%). The survey demonstrates that the Internet has assumed a definite place in the lives of researchers in the field of parasitology. Survey responses indicate a need for electronic journals. In our opinion, universities and parasitology societies should be urged to publish journals electronically on the Web. To diminish current problems involved in the finding of relevant information on the Internet, we strongly recommend careful reading of the instructions regarding the search engines used. Web pages with clear structures, small file sizes, precise HTML (hypertext markup language) key-word editing, and page titles would facilitate more accurate discovery of specific sites. In addition, there seems to be a need for regular publication of reviewed parasitology-link collections.


Assuntos
Alfabetização Digital , Internet , Parasitologia , Pesquisa , Europa (Continente) , Humanos , Inquéritos e Questionários
5.
Br J Cancer ; 83(4): 454-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10945490

RESUMO

Lymphoma of the mucosa-associated lymphoid tissue (MALT) type usually arises in MALT acquired through chronic antigenic stimulation triggered by persistent infection and/or autoimmune processes. Due to specific ligand-receptor interactions between lymphoid cells and high-endothelial venules of MALT, both normal and neoplastic lymphoid cells display a pronounced homing tendency to MALT throughout the body. In the case of neoplastic disease these homing properties may be responsible for lymphoma dissemination among various MALT-sites. According to this concept, we have standardized staging procedures in all patients diagnosed with MALT-type lymphoma. All patients with MALT-type lymphoma underwent standardized staging procedures before treatment. Staging included ophthalmologic examination, otolaryngologic investigation, gastroscopy with multiple biopsies, endosonography of the upper gastrointestinal tract, enteroclysis, colonoscopy, computed tomography of thorax and abdomen and bone marrow biopsy. Biopsy was performed in all lesions suggestive for lymphomatous involvement, and evaluation of all biopsy specimens was performed by a reference pathologist. 35 consecutive patients with histologically verified MALT-type lymphoma were admitted to our department. Twenty-four patients (68%) had primary involvement of the stomach, five (15%) had lymphoma of the ocular adnexa, three (8.5%) had lymphoma of the parotid, and three (8,5%) of the lung. Lymph-node involvement corresponding to stage EII disease was found in 13 patients (37%), only one patient with primary gastric lymphoma had local and supradiaphragmatic lymph-node involvement (stage EIII). Bone marrow biopsies were negative in all patients. Overall, eight of 35 patients (23%) had simultaneous biopsy-proven involvement of two MALT-sites: one patient each had lymphoma of parotid and lacrimal gland, conjunctiva and hypopharynx, conjunctiva and skin, lacrimal gland and lung, stomach and colon, and stomach and lung. The remaining two patients had bilateral parotideal lymphoma. Staging work-up was negative for lymph-node involvement in all of these eight patients. The importance of extensive staging in MALT-type lymphoma is emphasized by the demonstration of multiorgan involvement in almost a quarter of patients. In addition, our data suggest that extra-gastrointestinal MALT-type lymphoma more frequently occurs simultaneously at different anatomic sites than MALT-type lymphoma involving the GI-tract.


Assuntos
Linfoma de Zona Marginal Tipo Células B/patologia , Neoplasias Oculares/patologia , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática , Linfoma não Hodgkin/patologia , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/patologia , Neoplasias Parotídeas/patologia , Neoplasias Gástricas/patologia
6.
Radiologe ; 40(3): 227-32, 2000 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-10789120

RESUMO

OBJECTIVE: To investigate the feasibility, precision and usefulness of computer aided surgery in ENT-sinus surgery. MATERIAL AND METHODS: 5 Patients with chronic sinus pathology and an indication for sinus surgery were elected. For intraoperative navigation we used a Philips "NEUROGUIDE" system and surgical instruments with LED's. Navigation procedures are described in detail in the paper, the system's precision was measured by pointing at anatomical landmarks. The accuracy was measured as the distance in millimeter between the bony structures of the CT scan on screen and the haircross of the pointer's tip on the screen. Another parameter of the systems accuracy was calculated by the system itself as the root mean square error in millimeter (RMSE) between the registered markers position and the marker position in the CT data set. RESULTS: Axial 3/3/1 mm spiral CT provided sufficient resolution, data transfer via optical disk was practicable. Positioning of the navigation equipment required some experience and the registration of the patients head position needed attention, as the markers have to be pointed at precisely. During operation, the head tracking system must not change its position on the patients head to ensure a correct navigation display. The main advantage of the computed navigation system was the constant orientation during the sinus surgical procedure. Frontiers and critical anatomical structures could be identified in the corresponding CT data set, thus enabling the surgeon to decide on the further procedure. At present stage, the operation time was increased through the handling of the navigation system for at about 15 min, resulting in additional time of narcosis. CONCLUSION: We found the computed navigation system Philips "NEUROGUIDE" system to be an established technical aid, ready to use for ENT sinus surgery, in our cases with a precision between 1 and 3 mm. These results were similar to results obtained with a SPOCS Navigation System from Aesculap, as previously published by us [17].


Assuntos
Endoscópios , Processamento de Imagem Assistida por Computador/instrumentação , Doenças dos Seios Paranasais/cirurgia , Instrumentos Cirúrgicos , Tomografia Computadorizada por Raios X/instrumentação , Interface Usuário-Computador , Adulto , Processamento Eletrônico de Dados , Seio Etmoidal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/cirurgia , Pólipos Nasais/cirurgia
8.
J Clin Oncol ; 18(6): 1331-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10715305

RESUMO

PURPOSE: To report our experience with both (123)I-vasoactive intestinal peptide (VIP) and (111)In-DTPA-D-Phe(1)-octreotide for imaging to identify primary and metastatic tumor sites in carcinoid patients. PATIENTS AND METHODS: One hundred ninety-four patients with a verified or clinically suspected diagnosis of a carcinoid tumor were injected with (111)In-DTPA-D-Phe(1)-OCT for imaging purposes, while 133 patients underwent scanning with both (123)I-VIP and (111)In-DTPA-D-Phe(1)-OCT in random order. Imaging results were compared with computed tomography scans, results of conventional ultrasound, endosonography, and endoscopy, and results of surgical exploration in case of inconclusive conventional imaging. RESULTS: Primary or recurrent carcinoid tumors could be visualized with (111)In-DTPA-D-Phe(1)-OCT in 95 (91%) of 104 patients; metastatic sites were identified in 110 (95%) of 116 patients. In 11 (51%) of 21 patients with suggestive symptoms but without identified lesions by conventional imaging, focal tracer uptake located the carcinoid tumor. In addition, metastatic disease was demonstrated in three patients after resection. In a direct comparison in the 133 patients who underwent both imaging modalities, (111)In-DTPA-D-Phe(1)-OCT was found to be superior to (123)I-VIP, with 35 (93%) of 38 versus 32 (82%) of 38 scans being positive in primary or recurrent tumors, 58 (90%) of 65 versus 53 (82%) of 65 being positive in patients with metastatic sites, and seven (44%) of 16 versus four (25%) of 16 being positive in patients with symptoms but otherwise negative work-ups. Overall, additional lesions not seen on conventional imaging were imaged in 43 (41%) of 158 versus 25 (25%) of 103 scans with (111)In-DTPA-D-Phe(1)-OCT and (123)I-VIP, respectively. CONCLUSION: Both peptide tracers have a high sensitivity for localizing tumor sites in patients with ascertained or suspected carcinoid tumors, with (111)In-DTPA-D-Phe(1)-OCT scintigraphy being more sensitive than (123)I-VIP receptor scanning. Both, however, had a higher diagnostic yield than conventional imaging, as verified by surgical intervention or long-term follow-up. The combination of both peptide receptor scans does not seem to further enhance diagnostic information.


Assuntos
Tumor Carcinoide/diagnóstico por imagem , Radioisótopos de Índio , Radioisótopos do Iodo , Octreotida/análogos & derivados , Ácido Pentético/análogos & derivados , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Peptídeo Intestinal Vasoativo , Adulto , Idoso , Humanos , Pessoa de Meia-Idade
9.
Laryngoscope ; 110(2 Pt 1): 292-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10680932

RESUMO

OBJECTIVES: The use of three-dimensional navigation systems provides information on the structures surrounding the field of operation and thereby reduces the risk of iatrogenic damage. The computed tomography (CT) data conventionally used are provided by preoperative scanning procedures, which means that tissue changes coming about during surgery are not seen on the screen. An intraoperative CT scanning procedure being able to update the CT data could provide a solution. STUDY DESIGN: Endoscopic sinus operations using an intraoperative CT updating the three-dimensional navigation system were performed on six persons to find out, whether the above is true. METHODS: Different parameters, advantages, and disadvantages in the cases of these six patients were compared with a group of 22 patients who underwent conventional endoscopic sinus surgery with different three-dimensional navigation systems without updating the CT data set. RESULTS: The intraoperative CT for updating the three-dimensional navigation system provides useful information for the surgeon. CONCLUSION: Balancing its advantages against its disadvantages, the updating of the CT data set with intraoperative CT cannot be recommended for conventional standard endoscopic sinus surgery.


Assuntos
Endoscopia , Processamento de Imagem Assistida por Computador , Pólipos Nasais/cirurgia , Seios Paranasais/cirurgia , Sinusite/cirurgia , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Anestesia , Doença Crônica , Feminino , Humanos , Masculino
11.
Eur Radiol ; 10(12): 1976-82, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11305581

RESUMO

The aim of this study was to evaluate whether the use of a digital continuous speech recognition (CSR) in the field of radiology could lead to relevant time savings in generating a report. A CSR system (SP6000, Philips, Eindhoven, The Netherlands) for German was used to transform fluently spoken sentences into text. Two radiologists dictated a total of 450 reports on five radiological topics. Two typists edited those reports by means of conventional typing using a text editor (WinWord 6.0, Microsoft, Redmond, Wash.) installed on an IBM-compatible personal computer (PC). The same reports were generated using the CSR system and the performance of both systems was then evaluated by comparing the time needed to generate the reports and the error rates of both systems. In addition, the error rate of the CSR system and the time needed to create the reports was evaluated. The mean error rate for the CSR system was 5.5%, and the mean error rate for conventional typing was 0.4%. Reports edited with the CSR, on average, were generated 19% faster compared with the conventional text-editing method. However, the amount of error rates and time savings were different and depended on topics, speakers, and typists. Using CSR the maximum time saving achieved was 28% for the topic sonography. The CSR system was never slower, under any circumstances, than conventional typing on a PC. When compared with a conventional manual typing method, the CSR system proved to be useful in a clinical setting and saved time in generating radiological reports. The amount of time saved, however, greatly depended on the performance of the typist, the speaker, and on stored vocabulary provided by the CSR system.


Assuntos
Prontuários Médicos , Radiologia , Software , Fala , Humanos , Processamento de Texto
12.
Eur J Radiol ; 31(2): 141-51, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10565513

RESUMO

PURPOSE: To determine the number of radiologists who currently have Internet access, their use patterns on the Internet for Radiology purposes, the web sites they would recommend, and the potential site access to the Internet that they would like to see in the future. In addition, this study analyzed the best way to find nationwide radiological sites and their content. MATERIALS AND METHODS: In a nationwide survey, 854 Austrian radiologist were asked to fill out and return a questionnaire about Internet access, current problems, current and future use, which web site they recommend, and about the use of e-mail. Next, the available nationwide radiological sites were searched with seven major search engines using 37 different keywords, as well as by category search, and by searching for links on the homepages of the radiological departments of all Universities of Austria. Then, the offered information of the founded pages was classified in categories. RESULTS: Of the 210 (24.6%) radiologists who returned the questionnaire, 154 (73%) had Internet access. Time expenditure was considered the main problem using the Internet. The Internet was used for literature research by 69% of the radiologists with Internet access, for e-mail by 60%, and for congress information by 57%. In future, 43% would like to read electronic journals more often and 39% would like to use the web more intensively for scientific congresses. At the present time, we found 17 radiological web sites in Austria. The most promising way to find these sites was to use the search engines Alta Vista and Hotbot. Fifteen (88%) sites offered information for patients, seven (41%) for radiologists, five (29%) for students, and four (24%) for researchers. SUMMARY: Many radiologists in Austria already have Internet access, although time expenditure was considered the main problem with Internet use. Survey responses showed a need for electronic journals. To our point of view, Universities and radiological societies are urged to publish journals electronically on the Web. Alta Vista and Hotbot were the best search engines for radiological sites in our setting, and a careful reading of the specific search engine's instructions is recommended. In our experience, Web pages with clear structure, small file size, precise HTML keyword editing, and page titles, facilitate more accurate discovery of specific sites. In addition, there seems to be a need for regular publication of reviewed radiological link collections and the establishment of standards for teleconsulting.


Assuntos
Internet , Radiologia , Áustria , Coleta de Dados , Humanos , Internet/estatística & dados numéricos
13.
Radiologe ; 39(4): 276-81, 1999 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-10337696

RESUMO

At our hospital, an average MRI examination comprises 170 images. These examinations were evaluated exclusively on digital reporting systems with two high-resolution monitors for a period of 1 year. A retrospective analysis of this reporting method in comparison with films on a conventional viewing wall was performed with subjective and objective data. Radiologists and technicians were requested to evaluate the system on a subjective scale from 1 to 5 for seven topics (image analysis, inspection, time for reporting, handling, comparison with previous reports, quality of PC laser prints, training period). Moreover, personal interviews were conducted and protocols taken. Patient and image frequency, film costs, data transfer time and amount of system failures were evaluated as objective data. The most important results were: Two thirds of the film checking radiologists prefer the conventional viewing walls over the computer monitors. However, 70% of the residents prefer using the computer monitor for reporting. Seventy percent of the interviewed radiologists considered comparison with former examinations on film very difficult. Digitizing of former MRI examinations was not a convincing method; printing on a standard PC laser printer was considered to yield insufficient quality. The different acceptance between radiologists and residents seems to be related to different experiences. The reduction in film costs (48.6%) will improve further with complete PACS installation in the whole hospital. Data transfer rates are still poor; further improvement of network performance is necessary for convenient work. One whole MRI examination and report could be stored on CD-ROM for a cost of less than 2 euros. This could be a future means of cheap archiving and documentation suitable for viewing on any PC with DICOM III viewer. Images and reports could stay with the patients as in the past.


Assuntos
Periféricos de Computador , Imageamento por Ressonância Magnética/instrumentação , Sistemas de Informação em Radiologia/instrumentação , Ecrans Intensificadores para Raios X , Humanos , Internet/instrumentação , Microcomputadores , Avaliação da Tecnologia Biomédica
15.
Nephrol Dial Transplant ; 14(3): 666-75, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10193817

RESUMO

BACKGROUND: The bacterial and chemical contamination of dialysate fluids are important problems in haemodialysis therapy and may be caused by the water used for dialysate preparation. METHODS: We performed a survey of the microbiological and chemical quality of the water used in seven dialysis wards. Special attention was paid to the effects of each water treatment step, for example ion exchange, reverse osmosis and UV disinfection, on the number of bacteria (measured as colony forming units, CFU), the amount of endotoxin (endotoxin units, EU) and various chemical parameters, the main focus being on calcium, magnesium, sulphate, aluminium and heavy metals. RESULTS: CFU values exceeding the European Pharmacopeia value, determined at an incubation temperature of 22 degrees C, were found in the samples of raw water (20.0%, n=25), after ion exchange (66.7%, n=12), after reverse osmosis (33.3%, n=18) and also in samples of the dialysis water taken at the inlets (12.5%, n=40) and outlets (50.0%, n=18) of the machines. Whereas all raw water samples from the wards showed high mean values for endotoxin (0.56-9.10 EU/ml) and the endotoxin levels were often enhanced after ion exchange (0.13- >9.49 EU/ml), treatment by reverse osmosis led to a satisfactory decrease in endotoxin in all samples (<0.03 EU/ml). Sufficient reductions in calcium, magnesium and sulphate could only be achieved by the combined application of ion exchange and reverse osmosis. Mercury contamination was observed in the samples after ion exchange at three treatment plants, this was possibly caused by polluted regenerants. Increased amounts of aluminium, copper and zinc were found in water samples from different sites in the treatment systems and were caused by materials in contact with the water. CONCLUSIONS: A sufficient chemical water purification treatment system should consist of ion exchange and reverse osmosis. Attention has to be paid to the suitability of materials in contact with the water and of the chemicals used, for example regenerants or corrosion inhibitors. From the microbiological point of view, a safety UV disinfection step in the water-treatment system is favourable. To avoid bacterial recontamination periodic cleaning and disinfecting of the water-treatment and distribution systems, as well as the dialysis machine are essential. There is the need for complete guidelines regarding dialysis water that include all relevant chemical and microbiological parameters. Based on this standard, periodic examination of the water after each treatment step has to be performed.


Assuntos
Diálise Renal , Microbiologia da Água , Poluentes Químicos da Água/análise , Abastecimento de Água/normas , Metais/análise , Purificação da Água
16.
Vasa ; 28(1): 53-4, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10191709

RESUMO

This case report describes a patient with persistent left superior vena cava (LSVC) as discovered by difficult placement of a pulmonary artery catheter via the left subclavian vein. After positioning in wedge position, chest x-ray showed a catheter route suggestive of persistent LSVC. Since this abnormality may yield potential clinical complications, this possibility should be considered in every difficult central venous access.


Assuntos
Cateteres de Demora , Cuidados Críticos , Artéria Pulmonar , Veia Cava Superior/anormalidades , Adulto , Transplante de Medula Óssea , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico por imagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Artéria Pulmonar/diagnóstico por imagem , Pressão Propulsora Pulmonar , Radiografia , Insuficiência Respiratória/terapia , Veia Cava Superior/diagnóstico por imagem
17.
Am J Gastroenterol ; 94(1): 278-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9934776

RESUMO

Treatment options for hepatocellular cancer apart from surgical resection are limited because of the drug-refractory nature of this disease. Little is known about the role of somatostatin-receptors in hepatocellular cancer, and somatostatin analogs have not been investigated for treatment of this malignancy. We present the case of a 68-yr-old male, who was successfully treated with the long-acting somatostatin analog lanreotide.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Somatostatina/análogos & derivados , Idoso , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Masculino , Somatostatina/uso terapêutico
18.
Br J Cancer ; 79(3-4): 535-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10027326

RESUMO

Fourteen patients with metastatic pancreatic adenocarcinoma were treated with the long-acting somatostatin (SST) analogue lanreotide. No objective response was obtained, and the median survival was 4 months (range 1.8-7 months). Pancreatic cancer could not be visualized by means of SST-receptor (R) scintigraphy in our patients. In vitro data also demonstrated absence of SSTR2 expression, suggesting pancreatic cancer not to be a potential target for treatment with SST analogues.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Somatostatina/análogos & derivados , Adenocarcinoma/patologia , Adulto , Idoso , Antineoplásicos/farmacologia , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Peptídeos Cíclicos/farmacologia , Receptores de Somatostatina/biossíntese , Receptores de Somatostatina/efeitos dos fármacos , Somatostatina/farmacologia , Somatostatina/uso terapêutico , Análise de Sobrevida
19.
J Nucl Med ; 39(12): 2090-4, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9867148

RESUMO

1,4,7,10-tetraazacyclododecane-N,N',N",N'''-tetraacetic acid (DOTA)-lanreotide is a universal somatostatin (SST) receptor subtype ligand that binds to a large variety of human tumors. We report the case of a patient with metastatic gastrinoma who was treated with 90Y-DOTA-lanreotide. Before treatment, dosimetry with 111In-DOTA-lanreotide (150 MBq, 10 nmol) indicated a dose of 5.8 mGy/MBq for the recurrent abdominal gastrinoma, and a mean dose of approximately 1.0 mGy/MBq for liver metastases (i.e., 56 and approximately 10 mGy/MBq for 90Y-DOTA-lanreotide, respectively). After four infusions of 90Y-DOTA-lanreotide (each 1 GBq, approximately 30 nmol) over a 6-mo period, the 111In-DOTA-lanreotide scintigraphy of the liver had returned to a nearly normal condition and a remarkably decreased uptake by the recurrent gastrinoma was calculated (approximately 5 mGy/MBq for 90Y-DOTA-lanreotide). The imaging results were well-correlated with a 25% regression of the liver metastases as indicated by CT. Blood, urine and whole-body clearances of 111In-DOTA-lanreotide and 90Y-DOTA-lanreotide were very similar. The DOTA-lanreotide promises to be useful for functional tumor diagnosis (111In-DOTA-lanreotide) and receptor-mediated tumor radiotherapy (90Y-DOTA-lanreotide).


Assuntos
Gastrinoma/radioterapia , Gastrinoma/secundário , Compostos Heterocíclicos/uso terapêutico , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/radioterapia , Peptídeos Cíclicos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Gastrinoma/diagnóstico por imagem , Gastrinoma/patologia , Compostos Heterocíclicos/farmacocinética , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Excisão de Linfonodo , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Peptídeos Cíclicos/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Receptores de Somatostatina/agonistas , Recidiva , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
20.
J Nucl Med ; 39(11): 1928-36, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9829585

RESUMO

UNLABELLED: Imaging with radiolabeled somatostatin/vasoactive intestinal peptide analogs has recently been established for the localization diagnosis of a variety of human tumors including neuroendocrine tumors, intestinal adenocarcinomas and lymphomas. This study reports on the biodistribution, safety and radiation absorbed dose of 111In-1,4,7,10-tetraazacyclododecane-N,N',N",N'''-tetraacetic acid (DOTA)-lanreotide, a novel peptide tracer, which identifies hSST receptor (R) subtypes 2 through 5 with high affinity, and hSSTR1 with low affinity. METHODS: The tumor localizing capacity of 111In-DOTA-lanreotide was initially investigated in 10 patients (3 lymphomas, 5 carcinoids and 2 intestinal adenocarcinomas). Indium-111 -DOTA-lanreotide was then administered to 14 cancer patients evaluated for possible radiotherapy with 90Y-DOTA-lanreotide (8 neuroendocrine tumors, 4 intestinal adenocarcinomas, 1 Hodgkin lymphoma and 1 prostate cancer). After intravenous administration of 111In-DOTA-lanreotide (approximately = 150 MBq; 10 nmol/patient), sequential images over one-known tumor site were recorded during the initial 30 min after peptide application. Thereafter, whole-body images were acquired in anterior and posterior views up to 72 hr postinjection. Dosimetry calculations were performed on the basis of scintigraphic data, urine, feces and blood activities. A comparison with 111In-DTPA-D-Phe1-octreotide (111In-OCT) scintigraphy was performed in 8 of the patients. RESULTS: After an initial rapid blood clearance [results of biexponential fits: T(eff1) 0.4 min (fraction a1 80%) and T(eff2) 13 min (fraction a2 14%)], the radioactivity was excreted into the urine and amounted to 42% +/- 3% of the injected dose (%ID) within 24 hr and 62% +/- 6%ID within 72 hr after injection of 111In-DOTA-lanreotide. In all patients, tumor sites were visualized during the initial minutes after injection of 111In-DOTA-lanreotide. The mean radiation absorbed dose amounted to 1.2 (range 0.21-5.8) mGy/MBq for primary tumors and/or metastases. The effective half-lives of 111In-DOTA-lanreotide in the tumors were T(eff1) 4.9 +/- 2.2 and T(eff2) 37.6 +/- 6.6 hr, and the mean residence time tau was 1.8 hr. The highest radiation absorbed doses were calculated for the spleen (0.39 +/- 0.13 mGy/MBq), kidneys (0.34 +/- 0.08 mGy/MBq), urinary bladder (0.21 +/- 0.03 mGy/MBq) and liver (0.16 +/- 0.04 mGy/MBq). The effective dose was 0.11 +/- 0.01 (range 0.09-0.12) mSv/MBq. During the observation period of 72 hr, no side effects were noted after 111In-DOTA-lanreotide application. The 111In-DOTA-lanreotide radiation absorbed tumor dose was significantly higher (ratio 2.25 +/- 0.60, p < 0.01) when directly compared with 111In-OCT. CONCLUSION: Indium-111 -DOTA-lanreotide shows a high tumor uptake for a variety of different human tumor types, has a favorable dosimetry over 111In-OCT and is clinically safe.


Assuntos
Radioisótopos de Índio/farmacocinética , Peptídeos Cíclicos/farmacocinética , Somatostatina/análogos & derivados , Adenocarcinoma/diagnóstico por imagem , Adulto , Idoso , Tumor Carcinoide/diagnóstico por imagem , Feminino , Meia-Vida , Humanos , Linfoma/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/diagnóstico por imagem , Octreotida/farmacocinética , Radiometria , Somatostatina/farmacocinética , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
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