Neurofibromatosis type 1 is one of the most common genetic diseases with autosomic dominant inheritance pattern in humans. The main radiological findings are: scoliosis, kyphoscoliosis, bone erosions, abnormal osseous growth, pseudarthrosis, meningeal cysts, deformity of the posterior wall of the vertebral bodies ("scalloping"), pectus excavatum, osteolytic lesions in the long bones and central nervous system abnormalities. The authors present the statistical data from the analysis of the radiological findings in 82 patients with neurofibromatosis type 1 attending the "Centro de Pesquisa e Atendimento em Neurofibromatose", in São José do Rio Preto, SP, Brazil, a multidisciplinary center for the study and treatment of neurofibromatosis.

Keywords: Neurofibromatosis, Neurofibromatosis type 1, Radiology, Phacomatosis

Computed tomography is currently the method of choice for the diagnosis and staging of lymphomas. Computed tomography enables accurate measurement of both tumor extent and volume and provides information that can be used to plan an appropriate strategy for the treatment. The purpose of the present article is to describe and analyze the chest and abdomen computed tomography and ultrasound findings in HIV-negative patients with lymphoma. Clinical abnormalities, such as the reason the patient sought medical assistance already showing evidence of lymphocytic disease (not yet diagnosed at this point) and the physical examination abnormalities seen on the first consultation were also studied. This study comprised 30 patients: 40% with non-Hodgkin lymphoma, 46.6% with Hodgkin lymphoma, 10% with Burkitt's lymphoma and 3.3% with lymphoblastic lymphoma.

Keywords: Lymphoma, Computed tomography, Ultrasonography

Clinical examination alone is not sufficient to precisely evaluate lymph node involvement in head and neck cancer. The results of computed tomography of the neck and lymphoscintigraphy were evaluated in 21 patients with carcinoma of the mouth and oropharynx staged N0. Nine patients were treated by homolateral and 12 by bilateral neck dissection. Sensitivity and specificity of computed tomography were 16% and 73% for homolateral side and 0% and 90% for contralateral side, respectively. Lymphatic drainage was observed in 76.2% of the cases. No-migration was associated with cases involving the retromolar region and tonsillar fossa, where injection of the 99mTc-Dextran 500 is more difficult. Bilateral migration occurred only in carcinomas of the floor of the mouth, with involvement of the midline. From these results it was concluded that computed tomography was less efficient than clinical examination. Nevertheless, it must be considered that conventional computed tomography was used. We are currently undertaking similar studies with helical computed tomography. Lymphoscintigraphy showed promising results, and the same method to evaluate sentinel lymph nodes in patients with carcinoma of the mouth is being used.

Keywords: Scintigraphy, Nuclear medicine, Computed tomography

We correlated the anatomopathological abnormalities of the pleural space with the ultrasound findings in patients with pleural effusion and/or parapneumonic empyema and proposed a classification based on these results. Ultrasonography is a reliable method to infer the anatomopathological phase of pleural disease and consequently may be of help in the choice of the most suitable treatment.

Keywords: Ultrasonography, Pleural effusion, Pleural empyema

The aim of the present study was to establish the diagnostic value of abdominal ultrasonography in the diagnosis of appendicitis using 5--10 MHz multifrequency transducers. A transversal study of 240 consecutive patients examined from April 1996 to September 1998 due to suspected acute appendicitis was conducted. The ultrasonography criteria for acute appendicitis were noncompressible appendix with thickness above 6.0 mm, with or without apendicolith and/or collection. The adopted gold standard were surgical findings and clinical follow-up during one year. The prevalence of appendicitis was 59%. Abdominal ultrasound showed: sensitivity = 90%, specificity = 97%, accuracy = 93%, predictive positive value = 98%, predictive negative value = 87%, false positive = 2% and false negative = 13%. Ultrasonography using 5--10 MHz multifrequency transducers showed to be a very effective imaging diagnosis method for acute appendicitis.

Keywords: Appendicitis, Appendix ultrasonography, 5--10 MHz transducer, Ultrasonography

PURPOSE: To evaluate the influence on local control in adult patients with soft tissue sarcomas of the limbs that underwent limb-sparing surgery and high-dose rate brachytherapy (HDRB) in association with teletherapy. MATERIAL AND METHODS: Sixteen patients treated from 1993 to 1999 were reviewed. Teletherapy was used pre- or postoperatively (30--55 Gy) in association with HDRB in a dose range of 18--36 Gy (fx 3--6 Gy BID). The linear quadratic model was used to calculate the biological effective dose (BED) and the values obtained were compared with data from the literature, of studies that employed teletherapy and low-dose rate brachytherapy (LDRB). RESULTS: Soft tissue sarcomas BED mean and median values were 78.5 Gy7 and 80 Gy7, respectively. Univariated analysis showed that BED for patients with soft tissue sarcoma of the limbs submitted to HDRB was similar to the value of 83 Gy7 of patients submitted to LDRB (p = 0.008). Actuarial local control, disease free and overall survival rates at 5-years were 83.2%, 75% and 93.7%, respectively. CONCLUSIONS: HDRB appears to be an effective complementary method to teletherapy in the treatment of soft tissue sarcomas. The local control rates are comparable to those reported in the literature. However, studies with longer follow-up and a larger number of patients are still necessary in order to determine the true potential of HDRB as a substitute for LDBR.

Keywords: Soft tissue sarcoma, Brachytherapy, Limb-sparing surgery, Biological effective dose

This work describes a content-based image retrieval system developed to aid in the diagnosis of breast lesions by visual inspection through comparison of images. When an unknown image is presented the system extracts a vector of texture features and searches a database for images with similar characteristics, within a previously established approximation. The retrieved images are presented to the user for evaluation of the associated diagnoses.

Keywords: Content-based image retrieval, Pattern recognition, Texture features

The authors review the use of intraoperative ultrasonography (IOUS) in the management of biliary-pancreatic disease. The methodology of IOUS used for the examination of the biliary-pancreatic ductal system as well as the most important findings and pitfalls of image interpretation are described. Additionally, some ultrasonography findings in pancreatic tumors, pancreatitis, bile duct tumors and bile duct stones are presented. The authors emphasize the importance of understanding this ultrasonographic method due to the increasingly use of IOUS in biliary-pancreatic surgery.

Keywords: Intraoperative ultrasonography, Pancreas, Biliary ductal system

The authors report a case of a 4-year-old girl with headache, irritability, otorrhea, and unilateral exophthalmus. Computed tomography and plain films showed large lytic areas in the vault and base of the skull. No other bones were involved. The diagnosis of histiocytosis X (Hand-Schuller-Christian disease) was confirmed by bone marrow biopsy. This paper presents the cytological and radiological findings of this patient as well as a review of the literature.

Keywords: Histiocytosis, Histiocytosis X, Hand-Schuller-Christian, Skull

Ewing's sarcoma and Triton's tumor are two uncommon bone tumors of the skull that have nonspecific clinical and imaging features. However, imaging methods are important in the detection of the lesions during the diagnostic investigation in order to evaluate the extent of the bone lesions, involvement of soft tissues and brain, and to determine the presence of local recurrence and metastases. The confirmatory diagnosis relies on histological studies and immunohistochemistry. The authors report two cases of patients with these tumors and present the radiological findings.

Keywords: Ewing's sarcoma, Triton's tumor, Bone tumors, Skull, Computed tomography

The authors report the cases of two adolescent patients with recurrent respiratory papillomatosis with pulmonary parenchymal spread. Both patients presented very similar initial symptoms and clinical evolution. The patients developed larynx papillomas in childhood causing obstruction to airflow and required permanent tracheostomy after several resection and recurrence episodes. Long time after they developed recurrent pulmonary infections. In both cases the disease was diagnosed through clinical history and high-resolution computed tomography that revealed papillomas in the trachea and solid or cavitary nodules in the lungs.

Keywords: Larynx papillomas, Computed tomography, Lung

Gastric cancer frequently presents intraperitoneal spread. Distant metastases are rare. The authors describe a case of a 47-year-old white man, long-term cigarette smoker, who had a right upper lobe mass seen on plain films and computed tomography of the chest. A gastric adenocarcinoma was concomitantly diagnosed by endoscopic examination. A bronchoscopy guided biopsy showed that the lung mass was in fact a metastasis from gastric adenocarcinoma. In this article, the imaging findings of gastric cancer and the patterns of dissemination to other organs are reviewed.

Keywords: Gastric cancer, Lung metastasis, Bone metastasis, Computed tomography