OBJECTIVE: To identify chest radiography findings suggestive of type 1 neurofibromatosis, establishing their frequency and evaluating the possibility of including the presence of posterior mediastinal masses as a criterion for the diagnosis of type 1 neurofibromatosis. MATERIALS AND METHODS: The present study included 141 patients with type 1 neurofibromatosis assisted at the Service of Radiology of Hospital de Base and Faculdade de Medicina de São José do Rio Preto, SP, Brazil, and submitted to standard chest radiography in postero-anterior and lateral views. The results were analyzed by non-parametric methods and the level of statistical significance was set at 0.05 (p = 0.05). RESULTS: The most frequent findings were the following: ribs erosion (19.8%), pectus excavatum (12.0%), kyphoscoliosis (3.5%) and posterior mediastinal masses (7.1%). Such results suggest that posterior mediastinal masses (neurofibroma and meningocele) should be included as a diagnostic criterion of type 1 neurofibromatosis, in conjunction with dysplasia of the sphenoid wing, pseudoarthrosis and thinning of long bone cortex, as defined by the National Institutes of Health. CONCLUSION: The presence of posterior mediastinal masses in association with the typical bone changes defined by the National Institutes of Health is a consistent finding to be considered as a diagnostic criterion of the disease.

Keywords: Type 1 neurofibromatosis, Radiology, Chest radiography, Bone abnormalities, Mediastinal neoplasms

The authors report a case of neurofibromatosis type I, characterized by multiple plexiform neurofibromas in the retroperitoneum and pelvis. Computed tomography showed markedly hypodense lesions involving mainly the psoas and the paravertebral regions, findings which could mimic other diseases such as abscesses and lymphadenopathy. Magnetic resonance imaging was useful to better evaluate the extension and internal structure of the neurofibromas.

Keywords: Neurofibromas, Plexiform, Computed tomography, Magnetic resonance imaging

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

The authors report the case of a plexiform neurofibroma located in the pelvis, affecting the bladder, prostate and spine (lumbar/sacral), followed-up for three years and six months. Surgical removal was contraindicated and the patient underwent biannual clinical and radiological follow-up that did not demonstrate any tumor increase. The clinical manifestations of neurofibromatosis type 1 are variable, and the medical team should be attentive to further investigations, considering possible unexpected rare findings. Large pelvic masses may correspond to plexiform neurofibromas, so the diagnostic hypothesis of neurofibromatosis should be taken into consideration.

Keywords: Neurofibromatosis type 1; Plexiform neurofibroma; Pelvis.

OBJECTIVE: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). MATERIALS AND METHODS This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD).The sample comprised eight women and six men.The median age was 55 years (range, 11–75 years).The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S.National Institutes of Health.The images were analyzed by two chest radiologists, who reached decisions by consensus. RESULTS: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%).Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%).The pulmonary abnormalities were bilateral in 12 cases (85.7%).The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). CONCLUSION: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

Keywords: Neurofibromatoses; Cysts; Lung diseases; Tomography, X-ray computed.