Posterior reversible encephalopathy syndrome following immunoglobulin therapy in a patient with Miller-Fisher syndrome

Radiol Bras. 2016 Jan/Fev;49(1):56–64 58 http://dx.doi.org/10.1590/0100-3984.2014.0057 infarction, spontaneous or traumatic rupture, congestive heart failure, and Kasabach-Merritt syndrome. A correct diagnosis of the pedunculated lesion may be difficult, despite the typical radiological presentation, because of the limitation in define the origin of the mass, since a thin pedicle may be almost undetectable at images. The most used modalities of imaging in diagnosis include US, CT and MRI. At US, the image is typically hyperechoic, homogeneous, with well defined margins; and, in cases of giant lesions, central heterogeneity may be present. At CT, with a certain frequency, giant hemangiomas do not present with the typical pattern of hypoattenuating lesion with centripetal enhancement and homogenization at delayed sections, due to the presence of avascular areas of necrosis, fibrosis or hemorrhage. MRI is the most sensitive and specific (> 90%) diagnostic method. The lesions are well defined, homogeneous, with low signal intensity at T1-weighted sequences, and high signal intensity at T2-weighted sequences. Biopsy is not recommended in such cases, due to the risk of hemorrhage. There are reports in the literature describing pedunculated hemangiomas as gastric, adrenal tumor, retroperitoneal mass, other pedunculated liver tumors such as hepatocellular carcinoma, mesenchymal hamartoma, focal nodular hyperplasia or adenoma. Surgical treatment is reserved for cases of giant or symptomatic lesions, uncertain diagnosis, lesions with complications, and for cases of pedunculated hemangiomas due to their tendency to torsion. REFERENCES