ABSTRACT
Objective To study the MR features and differential diagnosis of oligodendroglioma.Methods Clinical and MR data of 34 pathology-diagnosed oligodendroglioma cases were analyzed retrospectively, which included tumor location,signal,size,enhanced and MRS features.Results 22 cases were diagnosed as WHOⅡoligodendroglioma and 12 cases WHOⅢ anaplastic oligodendroglioma.22 tumors located in the frontal lobes,4 tumors in the temporal lobes, 7 tumors in both frontal and temporal lobes,1 tumor located at the optic chiasma.25 tumors located in the superficial areas of the brain.For anaplastic oligodendrogliomas,tumor necrosis and cystic degenerations were showed in 11 cases,and hemorrhage or calcification in 6 cases.For oligodendroglioma,tumor necrosis and cystic degenerations were showed in 6 cases,hemorrhage in 2 cases,calcification in 8 cases.The average tumor diameter was 35 mm for oligodendroglioma and 58 mm for anaplastic oligodendroglioma.For anaplastic oligodendroglioma,obvious irregular or ring enhancements were showed in 11 cases.For oligodendroglioma, mild enhancement was showed in 6 cases,no enhancement in 6 cases and mild or moderate irregular ring-type enhancements in 4 cases.MRS was performed in 6 anaplastic oligodendrogliomas the Cho/Cr ratio was over 4 in 5 cases.MRS was performed in 12 oligodendrogliomas the Cho/Cr ratio was between 2.3 to 3.3 in 10 cases and below 2 in 2 cases.Conclusion The main MR feature of anaplastic oligodendroglioma is that tumor is located in the frontal lobe and superficial area of the brainwith irregular or ring-type enhancement,and the Cho/Cr ratio over 4.
ABSTRACT
Objective To investigate the clinical and MR features of fungal encephalopyosis and fungal granuloma.Methods The clinical and MR data of 10 cases with fungal encephalopyosis and fungal granuloma confirmed by surgical pathology or clinical serum were analyzed retrospectively.Then we analyzed the clinical conditions,MR signals,lesion enhancement,DWI and MRS performance characteristics of the 10 cases.Results Six cases were fungal encephalopyosis,among which 2 cases occurred in the sella turcica after surgery which located in and above the sella turcica.2 cases occurred in the frontal lobe after frontal surgery and 1 case of them was multiple encephalopyosis.2 cases of encephalopyosis without operation history were located in the left frontal lobe and right cerebellum respectively.The abscess walls of these cases were thin and showed high tension.Furthermore,it had annular significant signal enhancement and high signal in DWI scan.One case of huge fungal granuloma located in the frontal lobe and into the sinuses which showed uneven signal enhancement. The Cho level was significantly increased.Three cases of cryptococcal granuloma showed multiple lesions located in the bilateral basal ganglia region and 2 out of them accompanied with cephalomeningitis.Conclusion The MR performance of fungal encephalopyosis was quite similar with bacterial brain abscesses,which makes the differential diagnosis difficult.The brain fungal granuloma MRS may display a significant increase of Cho level which might be related with gliosis.It shows certain characteristics of brain MR performance of cryptococcal granuloma which are multiple lesions,preferential distribution of basal ganglia region and accompanying cephalomeningitis.