Fuldem Yildirim Donmez

MRI Features of Posterior Reversible Encephalopathy Syndrome in 33 Patients

We report the clinical and radiological features of posterior reversible encephalopathy and compare our findings to the literature.

MR Cholangiopancreatography with T2-Weighted Prospective Acquisition Correction Turbo Spin-Echo Sequence of the Biliary Anatomy of Potential Living Liver Transplant Donors

OBJECTIVE The objective of our study was to evaluate the ability of a respiratory navigator-triggered T2-weighted turbo spin-echo (TSE) sequence with a prospective acquisition correction (PACE) technique for MR cholangiopancreatography (MRCP) to depict the biliary anatomy of living donor liver transplantation (LDLT) donors. SUBJECTS AND METHODS Forty potential LDLT donors who ranged in age from 19 to 54 years were prospectively evaluated with preoperative MRCP. MRCP was performed with a 1.5-T magnetic field using T2-weighted PACE TSE sequence. MRCP source data sets were processed with maximum-intensity-projection (MIP) and shaded surface display (SSD) algorithms. Findings were compared with intraoperative cholangiography. Biliary anatomy was classified according to the classification proposed by Huang and colleagues. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRCP for the detection of aberrant biliary anatomy were calculated. RESULTS Intraoperative cholangiography and biliary exploration revealed that 27 donor candidates (67.5%) had conventional and 13 (32.5%) had aberrant biliary anatomy. Two donors (5%) had type B biliary anatomy; eight donors (20%), type C; two donors (5%), type D; and one donor (2.5%), unclassified. The sensitivity of MRCP source data sets in differentiating aberrant biliary anatomies from nonaberrant ones was 100%, the specificity was 88.9%, and the accuracy was 92.5%. PPV and NPV were 81.3% and 100%, respectively. The sensitivity of MIP images in differentiating aberrant biliary anatomies was 100%, the specificity was 88.9%, and the accuracy was 92.5%. PPV and NPV were 81.3% and 100%, respectively. The sensitivity, specificity, accuracy, PPV, and NPV of the SSD images in detecting aberrant biliary anatomies were 100%, 77.8%, 85%, 68.4%, and 100%, respectively. CONCLUSION Preoperative MRCP using a respiratory navigator-triggered T2-weighted TSE sequence with a PACE technique accurately depicts the biliary anatomy in LDLT donors and may guide intraoperative management of the biliary tract.

Evaluation of possible prognostic factors of fulminant acute disseminated encephalomyelitis (ADEM) on magnetic resonance imaging with fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging.

Background: Acute disseminated encephalomyelitis (ADEM) may be a rapidly progressive disease with different clinical outcomes. Purpose: To investigate the radiological findings of fulminant ADEM on diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) images, and to correlate these findings with clinical outcome. Material and Methods: Initial and follow-up magnetic resonance imaging (MRI) scans in eight patients were retrospectively evaluated for distribution of lesions on FLAIR images and presence of hemorrhage or contrast enhancement. DWI of the patients was evaluated as to cytotoxic versus vasogenic edema. The clinical records were analyzed, and MRI results and clinical outcome were correlated. Results: Four of the eight patients died, three had full recovery, and one had residual cortical blindness. The distribution of the hyperintense lesions on FLAIR sequence was as follows: frontal (37.5%), parietal (50%), temporal (37.5%), occipital (62.5%), basal ganglia (50%), pons (37.5%), mesencephalon (37.5%), and cerebellum (50%). Three of the patients who died had brainstem involvement. Two patients had a cytotoxic edema, one of whom died, and the other developed cortical blindness. Six patients had vasogenic edema: three of these patients had a rapid progression to coma and died; three of them recovered. Conclusion: DWI is not always helpful for evaluating the evolution or predicting the outcome of ADEM. However, extension of the lesions, particularly brainstem involvement, may have an influence on the prognosis.

Dynamic Contrast Enhancement Patterns of Solitary Pulmonary Nodules on 3D Gradient-Recalled Echo MRI

OBJECTIVE The purpose of this study was to determine whether contrast enhancement features on 3D volumetric gradient-recalled echoMR images allow differentiation of benign from malignant solitary pulmonary nodules. MATERIALS AND METHODS Forty patients with solitary pulmonary nodules (range of greatest diameter, 7-40 mm) detected on CT underwent unenhanced MRI and contrast-enhanced MRI performed in 10 consecutive dynamic 3D volumetric gradient-recalled echo sequences every 30 seconds. Contrast enhancement patterns (homogeneous, heterogeneous, rim, peripheral, and central) of the lesions were visually evaluated, and time-intensity curves of the lesions were drawn. RESULTS Twenty patients had benign lesions (nine, tuberculoma; one, aspergilloma; nine, round atelectasis; one, postinflammatory nodule). The other 20 patients had malignant lesions (18, primary lung cancer; two, metastasis). At visual analysis, all 20 malignant lesions displayed peripheral enhancement with progressive heterogeneous fill-in on the late images. All nine tuberculomas and the aspergilloma had rim enhancement, and all nine round atelectasis lesions and the postinflammatory nodule had early intense homogeneous enhancement. Regarding the time-intensity curves, all malignant lesions except one lung cancer lesion had early peak enhancement with rapid washout. All benign lesions displayed early increasing enhancement with an early plateau in the second minute after contrast administration (nine tuberculomas and one aspergilloma) or a late plateau in the fourth minute (nine round atelectasis lesions and one postinflammatory nodule). CONCLUSION Rim contrast enhancement is highly valuable in the diagnosis of tuberculoma. Time-intensity curve types can be taken into consideration for noninvasive differentiation of lung cancer, tuberculoma, and round atelectasis.

Diagnosis of early sacroiliitis in seronegative spondyloarthropathies by DWI and correlation of clinical and laboratory findings with ADC values

PURPOSE Sacroiliitis is one of the diagnostic criteria of seronegative SpA. The purpose of our study is to show the signal characteristics of the sacral and iliac surfaces by DWI which may contribute in early diagnosis of sacroiliitis and investigate the correlation between ADC values and clinical and laboratory parameters. MATERIALS AND METHODS 62 patients with inflammatory low back pain, with a history or suspect of seronegative SpA are enrolled into the study. 40 age and sex-matched subjects without SpA constituted the control group. After obtaining routine T1 and T2 weighted sequences, echo planar imaging at b values of 0, 400 and 800 was performed. ADC values on both surfaces of the both sacroiliac joints were measured in all subjects. The CRP and sedimentation results and the presence of arthritis and enthesitis were also correlated with the ADC values. RESULTS ADC values on both surfaces of the both sacroiliac joints were found 0.23 × 10(-3)mm(2)/sn in the control group. In the patient group, mean ADC value of 0.48 × 10(-3)mm(2)/sn was obtained (p<0.001), which was statistically significant, compatible with the increased diffusion due to medullary edema in early sacroiliitis. There was a slight correlation between CRP and ADC values; presumed to be showing the relation between the activity of the disease and the active inflammation on DWI. There was no correlation between arthritis and enthesitis and the ADC values (p>0.001). CONCLUSION DWI, by measuring ADC values, adds significant information in the early diagnosis of sacroiliitis and may help to evaluate the efficiency of the treatment.

Hippocampal abnormalities associated with various congenital malformations

ObjectiveOur objective in this retrospective study was to assess the hippocampal abnormalities, associate them with various congenital brain malformations, and define the frequency of the association in specific anomaly subgroups.MethodsA total of 62 patients with congenital malformations of the brain who had thin-slice coronal T2-weighted, fluid attenuated inversion recovery, IR, or T1-weighted 3D gradient echo images were retrospectively evaluated for the type of congenital brain malformation and morphological or rotational hippocampal abnormalities. Medical records were reviewed for age, sex, and symptoms.ConclusionHippocampal abnormalities are found in 55.8% of all patients with different kinds of congenital brain malformations that are mostly associated with cortical dysplasia, lissencephaly, and total agenesis of the corpus callosum. The severity of the injury may have an effect on the extent of the involvement of the brain.

Evaluation of Neurological Complications in Pediatric Liver Transplant Recipients: MRI Versus CT

With the aim of guiding choice of the best imaging modality for specific clinical conditions, we retrospectively evaluated neuroradiological findings in pediatric liver transplant recipients with neurological complications. Computed tomography (CT) was used to examine 31 patients with acute neurological symptoms after liver transplantation, and magnetic resonance imaging (MRI) was used for 35 such patients. A total of 16 patients belonged to both groups. Headache was the most common symptom in patients with computed tomography; seizure was most common among patients with magnetic resonance imaging. Magnetic resonance imaging detected additional abnormalities in 5 patients presenting with seizures whose computed tomography results were normal or insufficient to explain the clinical picture. In conclusion, liver transplant recipients with seizure should undergo magnetic resonance imaging emergently when possible; omitting computed tomography. Choice of imaging modality should be directed by nature of symptoms and time interval between transplantation and symptom onset.

Medulla oblongata tuberculoma mimicking metastasis presenting with stroke-like symptoms

Tuberculomas are common forms of central nervous system tuberculosis, presenting as space-occupying-lesions. Brainstem tuberculomas are rare among all intracranial tuberculomas. In old patients, in the absence of tuberculosis history, diagnosis may be challenging. In this case, we present a 70-year-old patient, with bladder cancer, without known tuberculosis who presented with stroke-like symptoms, clinically. Diffusion-weighted imaging revealed no finding of stroke, however, a medulla oblongata tuberculoma, mimicking metastasis was evident on MRI.

Abnormal diffusion-weighted imaging findings in an adult patient with acute cerebellitis presenting with a normal magnetic resonance imaging.

Acute cerebellitis is an unusual central nervous system complication of infectious disease often due to viral etiology. Diagnosis is aided by neuroimaging studies, actually by magnetic resonance imaging in the first place, which shows increased signal intensity on T2-weighted images. However, conventional magnetic resonance imaging may be unrevealing in some of the cases, and additional workup such as single photon emission computed tomography and diffusion-weighted imaging may be required. We present a case of acute cerebellitis in a 35-year-old woman diagnosed by diffusion-weighted imaging.

Multimodal MR imaging findings of a congenital glioblastoma multiforme

Dear Editor: We wish to report a case of congenital glioblastoma multiforme which is a rare high-grade glial tumor, with diffusionweighted magnetic resonance images and MR spectroscopy. Published reports are mostly based on clinical, genetical, and pathological behavior of the tumor; reports of radiological appearance are relatively uncommon. The imaging in those reports most commonly involved antenatal diagnoses by ultrasound; we did not recognize any report of MRI with diffusion and spectroscopy so far. An 8-month-old female infant from North Iraq presenting with an enlarging head was admitted to our hospital. The parents stated that they were told that the head circumference was larger than normal limits at birth. No further investigation was made at that time. On her routine follow-up onthe second month,aheadCTwasperformedbecauseoftheenlargedhead which revealeda supratentorialmass.The parents didnot seek any treatment at that time. Six months later, the baby was seen at our hospital, with the complaint of increasing enlargement of the head circumference. On physical examination, the patient was fine, with normal reflexes and normal responses to the stimuli, except for the macrocephaly. An MRI of the brain revealed a huge mass in the right frontal and parietal lobes which contained multiple small and large cystic areas and solid components that were isointense to gray matter on both T1-weighted- (Fig. 1a) and T2-weighted images. The