Diagnostic Accuracy of Mapping Techniques and Postprocessing Methods for Acute Myocarditis.

OBJECTIVE. Many T1 mapping sequences and measurement methods have been reported in the literature. To obtain accurate results, the most appropriate T1 and T2 mapping sequences and postprocessing methods should be used. The aim of the present study is to compare the T1 and T2 mapping sequences and measurement methods used to diagnose acute myocarditis. MATERIALS AND METHODS. Fourteen patients with an interval of 7 days or less between symptom onset and MRI examination were included in the study. The control group consisted of 22 healthy individuals. T1 mapping images acquired using four different methods (modified Look-Locker inversion recovery [MOLLI] 3[3]3[3]5, MOLLI 3[2]3[2]5, MOLLI 5[3]3 heart rate-corrected, and MOLLI 5[3]3 heart rate-uncorrected sequences) and T2 mapping images obtained using two different methods (FLASH and true fast imaging with steady-state precession) in the area from the short axis through the basal slice were retrospectively evaluated. RESULTS. The mean T1 and T2 values were significantly higher in the patient group than in the control group for all sequences in SAX measurements and segmental measurements (segments 1, 4, 5, and 6). Measurements from segments 2 and 3 were not statistically significant between patient and control groups. The segment with the highest AUC value of T1 and T2 mapping values was the inferior segment, followed by the inferolateral segment. The highest diagnostic performance for short-axis measurements was obtained using the MOLLI 3(2)3(2)5 sequence (AUC value = 0.902). CONCLUSION. According to the results of this study and many other studies, pathologic changes in the myocardium can be detected by native T1 and T2 mapping. The accuracy of mapping methods will increase with increased knowledge of the advantages and disadvantages of currently used sequences and measurement methods.

Is It Possible to Discriminate Active MS Lesions with Diffusion Weighted Imaging?

OBJECTIVE: Patients with multiple sclerosis (MS) are at a risk of gadolinium deposition because of multiple control imaging. Therefore, it is important to determine biomarkers that can differentiate active and chronic lesions without using contrast agent. This study aimed to assess mean apparent diffusion coefficient (ADC) values and signal intensities (SI) on diffusion weighted imaging (DWI) values of active and nonactive lesions. MATERIALS AND METHODS: We included 25 patients in this study. We measured mean ADC values and SI on DWI of the randomly selected active and nonactive lesions and normal appearing white matter (NAWM) for all patients with MS. SI on DWI and ADC values were normalized to the SI of the CSF. We compared all of the measurements between active and nonactive lesions, active lesions and NAWM, and nonactive lesions and NAWM. SI on DWI and mean ADC values of normal healthy white matter (NHWM) of control group were measured. A comparison was made between NHWM and NAWM. RESULTS: For patients with active lesions, the mean nADC value was 0.35±0.06 for active lesions and 0.30±0.07 for nonactive lesions (p>0.050). The mean nDWI-SI value was 3.69±0.68 for active lesions was 3.39±0.68 for nonactive lesions (p<0.050). When patients with and without active lesions were compared, both nDWI values and nADC values for active and nonactive lesions were statistically insignificant (p>0.050). DISCUSSION: In MS lesions, diffusion alternations can be quantitatively evaluated with ADC mapping. Lesions seen in patients with MS have higher mean ADC values than NAWM and NHWM.

Neuro-Ophthalmologic MRI Findings in the Detection of Rhinorrhoea Aetiology.

The purpose of this study is to evaluate the importance of neuro-ophthalmological magnetic resonance imaging (MRI) findings in the identification of the aetiology of rhinorrhoea, and the differentiation of spontaneous rhinorrhoea from non-spontaneous rhinorrhoea. MR images of 25 patients with spontaneous and 21 patients with non-spontaneous rhinorrhoea were evaluated for the presence of neuro-ophthalmological findings of intracranial hypertension (IHT). These include optic nerve vertical tortuosity, optic nerve sheath enlargement, flattening of the posterior sclera and optic nerve protrusion, as well as other MRI findings of ICH, such as partial empty sella, dilatation of Meckel's cave and the presence of arachnoid pits. IHT findings were more common in the spontaneous group. Six criteria (optic nerve distention, optic nerve vertical tortuosity, posterior flattening of the sclera, partial empty sella, Meckel's cave dilatation and presence of arachnoid pits) differentiate between patient and control groups. Patients with spontaneous cerebrospinal fluid (CSF) leaks should be evaluated for signs of IHT on MRI, as they are present in the majority of spontaneous CSF leaks and are representative of increased intracranial pressure.

Diagnostic Performance of Multiparametric MR Imaging at 3.0 Tesla in Discriminating Prostate Cancer from Prostatitis: A Histopathologic Correlation.

OBJECTIVE: To investigate the diagnostic performance of multiparametric magnetic resonance imaging (mpMRI) in differentiating prostate cancer (PCa) from prostatitis foci. MATERIALS AND METHODS: This retrospective analysis included 81 biopsy-proven lesions (44 prostatitis and 37 PCa). Normalized T2-signal intensity (nT2SI) and SI on diffusion-weighted imaging (b=1000 and 2000 mm2/s), apparent diffusion coefficient (ADC) values, peak SI, SI at the end of the dynamic curves, mean peak time, mean enhancement percentage, and washout percentage obtained from dynamic contrast-enhanced imaging (DCEI) were measured. RESULTS: nT2SI (3.8 vs. 3.2, p=0.003) and ADC values (0.685×10-3 mm2/s vs. 0.874×10-3 mm2/s, p<0.001) were significantly higher in the prostatitis group than in the PCa group. The washout percentage was the only DCEI parameter that was significantly different between the two groups (12% vs. 4%, respectively, p=0.003). The ADC values alone showed higher sensitivity (80.5%) and specificity (75%) than all of the single criteria and most of the combined criteria. The combination of nT2SI, ADC values, and washout percentage (at least two positive criteria were sufficient for a diagnosis of PCa) yielded the highest sensitivity (77.7%) and specificity (85.7%) among all combinations. CONCLUSION: PCa and prostatitis can be discriminated using mpMRI with high sensitivity and specificity.