ABSTRACT
Background Magnetic resonance imaging (MRI) is the imaging modality of choice for evaluating perianal fistulae, due to its ability to show the relationship of perianal fistulae with anal sphincters, fistula extensions, secondary ramifications and associated complications. Aim To evaluate the role of diffusion-weighted MRI in the evaluation of perianal fistulae. Settings and Design A hospital-based cross-sectional study. Materials and Methods The study group composed of 47 patients of perianal fistula. MRI with diffusion-weighted imaging (DWI) was performed with Philips 0.5 T Ingenia scanner. DWI with different b -values ( b = 50, b = 400, and b = 800 smm 2 ) were obtained. The MRI findings were correlated with local clinical examination and or surgical findings. Statistical Analysis Used Chi-square test, independent samples t -test, and receiver operating characteristic curve analysis. Result Fifty-nine perianal fistulas in 47 patients were included in the study sample. The visibility of perianal fistula on DWI was less than T2-weighted (T2W) and combined DWI-T2W images. Distinctly visualized (visibility score 2) perianal fistulas were observed in 47 fistulas (79.6%) on DWI, 54 (91.5%) on T2W, and 58 (98.3%) on DWI-T2W images. The mean of apparent diffusion coefficient (ADC) values of active fistula was 0.972 ± 0.127 [SD] 10 -3 mm 2 /s and inactive was 1.232 ± 0.185 [SD] 10 -3 mm 2 /s with a significant difference ( p -value < 0.0005). A cut-off mean ADC value of 1.105 × 10 -3 mm 2 /s was used to differentiate active from the inactive fistula with a sensitivity of 87.5% and specificity of 73.3%. Conclusion Combined DWI-T2W evaluation had a better performance in the detection of fistula than DWI or T2W alone. DWI with mean ADC calculation had a good performance in differentiating active from the inactive fistulas.
ABSTRACT
Background Multiecho fast field echo (mFFE) MRI sequence provides added value to the conventional MR imaging in evaluation of acute spinal trauma, especially for detecting spinal cord hemorrhage which is a best predictor for patient prognosis. Objective This study aims to evaluate the diagnostic efficacies of three-plane mFFE MRI sequence along with the conventional MRI sequences in acute spinal trauma patients using sensitivity. Materials and methods This prospective study comprised of 48 patients of acute spinal trauma. The neurological deficit of acute spinal trauma patients assessed according to the American Spine Injury Association (ASIA) scale. The correlation between the various MRI findings of acute spinal cord injury and neurological deficits were compared with the Chi-square test. Results Of 48 patients of acute spinal trauma, 36 males and 12 females with a mean age of 38.71±1.42 [SD] years. 22 (45.8%) patients had cord edema with a mean length of was 3.45±5.52 [SD] cm. The mean percentage of spinal canal compromisation was 39.47±25.47 [SD] and spinal cord compression 18.1±24.4 [SD]. There was statistical significance between the ASIA impairment scale and spinal canal compromisation and cord compression with a p-value of 0.0005. Cord hemorrhage observed in 13 (27%), non-hemorrhagic cord contusions in 3 (6.3%), cord transection in 5 (10.4%) and epidural hematoma in 10 (20.8%) patients with an initial high grade of ASIA scale. The visibility score of three-plane mFFE sequence was higher in comparison to the single plane sagittal mFFE and short tau inversion recovery (STIR) sequences. For detection of spinal cord hemorrhage with visibility score of 2, the three-plane mFFE had sensitivity of 77% followed by 38.5% with single plane sagittal mFFE and 7.7% with sagittal STIR images. 26 (54.2%) patients showed neurological improvement in their hospital stay/follow-up period and no improvement observed in 7 (14.6%) patients of acute spinal trauma. Conclusions Application of three-plane mFFE sequences detects more spinal cord hemorrhages and vertebral fractures with a better visibility score as compared to the single sagittal plane mFFE and STIR sequence.
