OBJECTIVE: To report an experiment involving the introduction of a protocol utilizing commercially available three-dimensional 1H magnetic resonance spectroscopy imaging (3D 1H MRSI) method in patients diagnosed with prostatic tumors under suspicion of neoplasm. MATERIALS AND METHODS: Forty-one patients in the age range between 51 and 80 years (mean, 67 years) were prospectively evaluated. The patients were divided into two groups: patients with one or more biopsies negative for cancer and high specific-prostatic antigen levels (group A), and patients with cancer confirmed by biopsy (group B). The determination of the target-area (group A) or the known cancer extent (group B) was based on magnetic resonance imaging and MRSI studies. RESULTS: The specificity of MRSI in the diagnosis of prostate cancer was lower than the specificity reported in the literature (about 47%). On the other hand, for tumor staging, it corresponded to the specificity reported in the literature. CONCLUSION: The introduction and standardization of 3D 1H MRSI has allowed the obtention of a presumable diagnosis of prostate cancer, by a combined analysis of magnetic resonance imaging and metabolic data from 3D 1H MRSI.

Keywords: Magnetic resonance spectroscopy imaging, Prostate, Prostatic neoplasm

OBJECTIVE: To evaluate metabolite concentration in the masseter of patients with systemic sclerosis, by analyzing creatine, choline, lipid and lactate levels, and correlating them with the presence of mandibular osteolysis. MATERIALS AND METHODS: The sample included 25 individuals, 15 of them with diagnosis of systemic sclerosis, divided into two groups according to the presence (group I) or absence (group II) of osteolysis, and 10 healthy individuals (group III, control). All of them were submitted to proton magnetic resonance spectroscopy with PRESS sequence and 3D acquisition. RESULTS: Metabolite analysis showed that the creatine and lipid levels were the same for the three groups. Patients in group I presented higher levels of choline when compared with group III. On the other hand, lower lactate levels were observed in groups I and II when compared with the healthy individuals. Creatine/lipid and choline/lactate ratios were the same in the three groups. CONCLUSION: Lower lactate levels were observed in the patients with systemic sclerosis (groups I and II). Choline levels were increased in the patients with mandibular osteolysis (group I). Creatine/choline, lipid/lactate and choline/lipid ratios were different among the three groups. Further studies are necessary to understand the role played by the masseter in the development of mandibular osteolysis.

Keywords: Masseter, Systemic sclerosis, Proton spectroscopy

OBJECTIVE: To develop and test a model of the human lumbar vertebra for training transpedicular puncture in percutaneous vertebroplasty. MATERIALS AND METHODS: Thirty lumbar vertebra models were constructed from methacrylate, plaster and ethyl-vinyl-acetate, using a rubber mold of human vertebrae. The intervertebral discs were made of silicone to provide anatomical similarity and fusion of five vertebrae. This model of spinal column segment was positioned within a manikin with an ethyl-vinyl-acetate lining so that direct visualization was not possible. A theoretical course was given to six trainees in radiology and neuroradiology who have tested the models with respect to parameters of similarity with the reality, performing 30 transpedicular punctures in three series of ten punctures a day, with one-week interval between the series. RESULTS: Each student performed 30 transpedicular punctures; however, eight of these punctures were disregarded because of manufacturing defects of the dummies observed during the procedures. Similarity data forms were filled in by all of the trainees following the procedures, with 100% of positive answers as regards the models similarity with the human body. CONCLUSION: It was possible to develop a training model for transpedicular puncture with a satisfactory degree of similarity with the human body, constituting an appropriate tool for training in vertebroplasty.

Keywords: Spine, Puncture, Learning, Manikin, Vertebroplasty

The conus medullaris is frequently affected by inflammatory and infectious lesions which many times are hardly differentiated because of the similarity of their clinical history and physical examination among the different etiologies. Magnetic resonance imaging presents high sensitivity in the detection of these lesions and plays a relevant role in the diagnosis as well as in the evolutive control of the condition. The present pictorial essay with selected cases from the archives of the authors' institution is aimed at demonstrating imaging findings which might help in the diagnosis of a specific etiology amongst inflammatory an infectious conditions and in the differentiation with diseases of neoplastic and vascular etiologies, for example. Findings such as enhancement pattern, presence of cysts, edema and involvement of other regions of the central nervous system are important for this differentiation, and may define a specific etiology as associated with clinical and laboratory tests findings.

Keywords: Magnetic resonance imaging; Myelitis; Transverse myelitis; Schistosomiasis.

OBJECTIVE: To develop a simulator for training In fluoroscopy-guided facet joint Injections and to evaluate the learning curve for this procedure among radiology residents. MATERIALS AND METHODS: Using a human lumbar spine as a model, we manufactured five lumbar vertebrae made of methacrylate and plaster. These vertebrae were assembled in order to create an anatomical model of the lumbar spine. We used a silicon casing to simulate the paravertebral muscles. The model was placed into the trunk of a plastic mannequin. From a group of radiology residents, we recruited 12 volunteers. During simulation-based training sessions, each student carried out 16 lumbar facet injections. We used three parameters to assess the learning curves: procedure time; fluoroscopy time; and quality of the procedure, as defined by the positioning of the needle. RESULTS: During the training, the learning curves of all the students showed improvement in terms of the procedure and fluoroscopy times. The quality of the procedure parameter also showed improvement, as evidenced by a decrease in the number of inappropriate injections. CONCLUSION: We present a simple, inexpensive simulation model for training in facet joint injections. The learning curves of our trainees using the simulator showed improvement in all of the parameters assessed.

Keywords: Zygapophyseal joint; Injections, intra-articular; Injections, spinal; Learning curve; Models, anatomic; Radiology, interventional.