1411. Differentiation of Fungal Abscess of Brain From Brain Glioblastoma by MRI Scan ADC Value

BACKGROUND: Differentiation of Brain fungal abscess from brain glioblastoma is very important. Treatment strategies are different in both cases. Glioblastoma needs different surgical planning as compared with abscess. We hypothesized that preoperative MRI brain will help in differentiation. METHODS: A retrospective study was carried out at Aga Khan University Hospital Karachi. Data from 2007 to 2017 was retrieved from Medical records using ICD-9 coding. 90 patients (47 males and 43 females; age range 10–70 years) with aggressive grade IV brain lesion and fungal abscess was selected and their preoperative MRI data were retrieved. The apparent diffusion coefficient (ADC) maps were reconstructed from diffusion-weighted imaging DWI data. The mean ADC value and standard deviation of glioblastoma and fungal abscesses were calculated. Postoperative biopsy results were used as gold standard.The analysis of data was done to test statistically significant differences between glioblastoma and fungal brain abscess. Receiver operating characteristic (ROC) curve was used to determine the cut-off point with highest accuracy that was used to differentiate malignancy from infection. The statistical analysis of data was done using SPSS® v. 19. RESULTS: The mean (±standard deviation) ADC value of fungal brain abscess (826.040 ± 94.97 × 0.001 mm(2)/sec) was significantly lower than that of glioblastoma (1,462.800 ± 163.66 × 0.001 mm(2)/sec). When an ADC value of 1,200 × 0.001 mm(2)/s used as a cutoff value for differentiating fungal abscess from glioblastoma the best result was obtained with an accuracy of 85%, sensitivity of 81%, specificity of 88%, negative predictive value of 80%, and positive predictive value of 90%. CONCLUSION: ADC value is a noninvasive promising imaging parameter that can be used for differentiation of fungal brain abscess and glioblastoma on preoperative scan. The cut-off value with best accuracy in our study was 1,200 × 0.001 mm(2)/s. [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.