Study Of Intracranial Tuberculosis During Antituberculous Treatment Using Serial Dynamic MRI

Background and 0bjective Tuberculosis can involve any organ or system in the body, about 6 percent of tuberculosis can involve central nervous system. The diagnose of intracranial tuberculosis was depended on the detection of acid-fast bacilli(AFB) and Mycobacterium tuberculosis by the cerebrospinal fluid , but this method get result slowly,and the process of the Mycobacterium tuberculosis is comparatively slow, so it is difficult to make diagnosis early. Magnetic resonance image has been extensively used to diagnosis of intracranial tuberculosis for for its peculiar advantages.The purpose of this study is to investigate the MR imaging feature, to correctly understand the imaging characteristics and standard typing of intracranial tuberculosis ,it can improve the diagnostic accuracy of intracranial tuberculosis. The average ADC from the Ring-like contrast enhancement of parenchymal tuberculosis and cerebral metastasis from the lung cancer, was measrued to use for differential diagnosis. The use of serial dynamic MRI as a tool to observe of effect of anti-tuberculosis therapy, to detect the dynamic change, in order to diagnose definitely and provide scientific basis for clinical therapy.Materials and method All the patients who have received MRI and hospitalized in Beijing Chest Hospital with the final diagnosis of intracranial tuberculosis from september 2009 to february 2011 were reviewed. Detail data of all subjects were recorded, which include laboratory examination medical record, and the findings of MRI. All MRI scans were obtained with a GE Signa HDxt 1.5 T MRI Scanner, 8NVHEAD NECK coil. The MRI protocol was identical for all patients and included five axial sequences: contrast enhanced T1WI, T1 FLAIR, T2 FLAIR, T2-weighted sequence, and diffusion weighted imaging (DWI). Main outcome measures: the MRI findings of intracranial tuberculosis, the ADC from parenchymal tuberculosis and 35 cases of cerebral metastasis from the lung cancer,the dynamic MRI findings after an interval of two, four, six, nine months. Datas are analyzed by SPSS13.0 software packet, and using t test and Chi-square tests.Results (1) Parenchymal tuberculosis lesions (38 cases): Lesions present multiply ,and distribute widely, 47.9% of the lesions were less than 0.3 cm, 37.4% of the lesions were between 0.3 cm to 1.0cm, 14.7% of the lesions were greater than 1.0cm. Parenchymal tuberculosis lesions can be classified into three types: the type of miliary brain tuberculosis, the type of tubercles and the type of tuberculoma.lesions showed nodular enhancement on Gd-DTPA enhanced T1WI,or showed Ring-like contrast enhancement of the rim on Gd-DTPA enhanced T1WI, and the center didn't show enhanced. The average ADC from the center of lesion was greater than the contralateral Brain parenchyma, there was statistical significance .Tuberculosis meningitis (24 cases): the meninges of the basic cistern showed contrast. The mixed type (10 cases): had the characteristics of MRI of the above two typies. (2)The average ADC from the cerebral metastasis from the lung cancer was greater than the Ring-like contrast enhancement of parenchymal tuberculosis, there was statistical significance. (3)38 cases of serial dynamic MRI findings:â‘ parenchymal tuberculosis: The absorption rate of the miliary brain tuberculosis less than 0.3 cm in size was 46.8 % after 3 month treatment, 78.6% after 6 month treatment, and The absorption rate of the miliary brain tuberculosis which showed nodular enhancement was 73.5 % after 3 month treatment. The absorption rate of the tubercles between 0.3 cm to 1.0cm in size was 32.0 % after 3 month treatment, 48.5% after 6 month trea- tment. The absorption rate of the peripheral edema of focus was 57.9% after 3 month treatment, 84.2% after 6 month treatment.â‘¡paradoxical development of intracranial tuberculosis during drug therapy belongs to Herxheimers reaction, go on with the treatment,the lesions became smaller.â‘¢The effect of the treatment of tuberculous meningitis was worse than parenchymal tuberculosis, the affecting the meninges didn't completely absorbe within 4 months anti-tuberculosis medication.Conclusions Parenchymal tuberculosis lesions can be classified into three types by the MRI characteristics: the type of miliary brain tuberculosis, the type of tubercles and the type of tuberculoma. The average ADC and the MRI fingdings were different among parenchymal tuberculosis and the cerebral metastasis from lung cancer. The intracranial tuberculosis dynamic change during anti-tuberculosis therapy can be described objectively by serial dynamic MRI.