Giant Cell Tumor and Giant Cell Reparative Granuloma of Bone of the Head: CT and MR Imaging Findings.

BACKGROUND: This study aimed to determine the features and differentiation of Giant Cell Reparative Granuloma (GCRG) and Giant Cell Tumor (GCT) of the head on CT and MRI. METHODS: This retrospective study included six patients with histopathology-confirmed head GCRG and 5 patients with histopathology-confirmed head GCT. All images were independently reviewed by two radiologists. The growth pattern, bone changes, MRI signal intensity, enhancement patterns and other image features were recorded. All patients received CT scans and MR images. RESULTS: All the lesions were located centrally in the bone. Osteolytic bone destruction and expansive growth patterns were observed on CT images. Four of six cases broke the cortical bone with residual cortical bone, and the last two showed a thin cortex in GCRG. Five cases broke the cortical bone with residual cortical bone in GCT. There were enhancing septations in GCT lesions on contrast- enhanced T1-Weighted Images (T1WI) while enhancing septations were not present in GCRG cases. The size of GCT lesions was larger than that of GRCG. GCRG and GCT showed iso-low signals on T1WI and iso-high signals on T2-Weighted Images (T2WI). There was a case with cystic or necrotic lesions in each of the two types of lesions. Osteolytic bone destruction and expansive growth patterns were observed in GCTs and GCRGs. CONCLUSION: The size of the GRCG lesion was smaller than that of the GCT. The presence of enhancing septations and the size of the lesion may distinguish GCTs from GCRG.

Splenic siderotic nodules in patients with liver cirrhosis.

The aim of this study was to investigate the interrelation between splenic siderotic nodules, hypersplenism and liver function in patients with liver cirrhosis. The splenic enhanced susceptibility-weighted angiography (ESWAN) and conventional magnetic resonance images of 33 patients with liver cirrhosis were retrospectively studied and the ESWAN images were graded. The distribution and prevalence of the image grades for patients with and without hypersplenism were evaluated. In addition, the splenic volume and the distribution of Child-Pugh and albumin scores were compared between patients with and without siderotic nodules, and the correlation between splenic volume and the ESWAN image grades were evaluated in the patients with siderotic nodules. The ESWAN images revealed splenic siderotic nodules in 24 patients. The distribution and prevalence of the ESWAN image grades were demonstrated to be significantly different (P<0.001) between patients with and without hypersplenism. Furthermore, significant differences were observed between patients with and without siderotic nodules with regard to splenic volume and the distribution of Child-Pugh and serum albumin scores (P<0.001). No significant correlation was demonstrated between splenic volume and the ESWAN image grades (P>0.05). In conclusion, a higher prevalence of splenic siderotic nodules (72.7%) was observed using the ESWAN sequence, in comparison with results from previous studies, obtained using the T1-spoiled gradient echo sequence. The presence of splenic siderotic nodules was consistent with the occurrence of hypersplenism and was interrelated with reserved liver function.