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G C Gomes

Publications and source records attributed to G C Gomes.

3 recordsLinked to original sources

MR imaging of intramedullary and intradural-extramedullary spinal cysticercosis.

OBJECTIVE: The purpose of our study was to retrospectively review the MR imaging findings in a group of patients with clinically proven cysticercosis involving the spinal cord, the spinal subarachnoid space, or both. MATERIALS AND METHODS: We retrospectively reviewed images of 16 patients with clinically diagnosed spinal cysticercosis to summarize the imaging characteristics. All patients underwent T1- and T2-weighted sagittal, axial, or both sagittal and axial MR imaging before i.v. administration of paramagnetic contrast media. Thirteen patients also underwent sagittal, axial, or both sagittal and axial T1-weighted MR imaging after i.v. gadolinium administration. In addition, all patients underwent cranial CT, MR imaging, or both to reveal possible evidence of cranial cysticercosis. RESULTS: MR imaging revealed isolated intradural-extramedullary involvement (n = 9), isolated intramedullary involvement (n = 3), combined intradural-extramedullary and intramedullary involvement (n = 3), and/or syringomyelia caused by infection and associated with chronic spinal arachnoiditis (n = 2). Evidence of intradural-extramedullary disease included cystic structures within the subarachnoid space or homogeneous sheetlike enhancement within the subarachnoid space over the surface of the spinal cord. Evidence of intramedullary disease included focal cystic lesions or syringomyelic cavitation of the spinal cord. All patients had evidence of simultaneous intracranial cysticercosis as shown on cranial CT, MR imaging, or both. CONCLUSION: In the absence of scolex visualization, cysticercotic involvement of the spinal cord or spinal subarachnoid space has a nonspecific appearance on MR imaging. On the basis of the findings in this group of patients, we believe that spinal cysticercosis is most often accompanied by intracranial disease.

Adult↗

Diffusion of calcium through dentin.

The purpose of this research was to investigate whether calcium ions from a paste of calcium hydroxide [Ca(OH)2] and saline introduced into root canals diffuse through the dentin to reach the surface of the root. Six teeth were opened and submitted to a biomechanical process, after which all the smear layer was removed. The experiment was divided into three phases: dissolution, dissolution and diffusion I, and dissolution and diffusion II. Dissolution-each tooth, with no Ca(OH)2 paste in place, was sealed both cervically and apically and stored in 700 ml of deonized water until calcium losses from the tooth into the water were stabilized. Dissolution and diffusion I-each root canal was filled with a paste of Ca(OH)2 and saline, sealed again apically and cervically, and returned to its solution. Dissolution and diffusion II-samples were divided into three parts: the control group or group 1, containing the original paste; group 2, in which the existing paste was diluted and the teeth were resealed and replaced in their solutions; and group 3, in which the existing paste was removed and a fresh paste was introduced. The diffusion was greater in group 3, followed by group 2. In the control group, we found a diffusion of calcium, which is statistically null. The results showed that calcium diffusion was observed, in the first 16 days, in all situations in which there was Ca(OH)2 paste inside the root canals.

Calcium↗