Multiple occipital defects caused by arachnoid granulations: Emphasis on T2 mapping.
A 56-year-old man presented with a 6-mo history of headache. Although neurological and laboratory examinations were normal, computed tomography (CT) scan was performed which revealed multiple occipital osteolytic lesions, which were suspected to be multiple myeloma. Subsequently nuclear magnetic resonance imaging (MRI) showed that these lesions presented with a cerebrospinal fluid (CSF)-like signal intensity, no diffusional restriction and intrinsic mass-like enhancement on conventional sequences were seen. T2 relaxation time was similar to that of CSF in the ventricles and adjacent subarachnoid space on T2-mapping. Single photon emission CT with (99m)Tc-Methyl diphosphonate was performed which revealed no increased radiotracing accumulation. Finally, these lesions were diagnosed as mutiple arachnoid granulations (AGs). The headache was treated symptomatically with medical therapy. On follow up examination after 6 mo no evidence of tumor was detected. This report aimed to illustrate the appearance and differentiation of occipital defects caused by multiple AGs on CT and MRI, with emphasis on the findings from T2 mapping.
Chao-Xuan Lu, Yong Du, Xiao-Xue Xu, Yang Li, Han-Feng Yang, Shao-Qiang Deng, Dong-Mei Xiao, Bing Li, Yun-Hong Tian, Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, Sichuan Province, China.
Chao-Xuan
CX
Lu
Yong
Y
Du
Xiao-Xue
XX
Xu
Yang
Y
Li
Han-Feng
HF
Yang
Shao-Qiang
SQ
Deng
Dong-Mei
DM
Xiao
Bing
B
Li
Yun-Hong
YH
Tian