T2 HASTE Research Articles

Comparison of 3D Maximum intensity projection (MIP) reconstruction and 2D T2 Half-Fourier Acquisition Single-Shot Turbo Spin-Echo (HASTE) sequence in magnetic resonance cholangiopancreatography

Introduction: Magnetic resonance cholangiopancreatography (MRCP) is a method that allows noninvasive visualization of pancreatobiliary tree and does not require contrast application. It is a modern method based on heavily T2-weighted imaging (hydrography), which uses bile and pancreatic secretions as a natural contrast medium. Certain weaknesses in quality of demonstration of pancreatobiliary tract can be observed in addition to its good characteristics. Our aim was to compare the 3D Maximum intensity projection (MIP) reconstruction and 2D T2 Half-Fourier Acquisition Single-Shot Turbo Spin-Echo (HASTE) sequence in magnetic resonance cholangiopancreatography.Methods: During the period of one year 51 patients underwent MRCP on 3T „Trio“ system. Patients of different sex and age structure were included, both outpatient and hospitalized. 3D MIP reconstruction and 2D T2 haste sequence were used according to standard scanning protocols.Results: There were 45.1% (n= 23) male and 54.9% (n=28) female patients, age range from 17 to 81 years. 2D T2 haste sequence was more susceptible to respiratory artifacts presence in 64% patients, compared to 3D MIP reconstruction with standard error (0.09), result significance indication (p=0.129) and confidence interval (0.46 to 0.81). 2D T2 haste sequences is more sensitive and superior for pancreatic duct demonstration compared to 3D MIP reconstruction with standard error (0.07), result significance indication (p=0.01) and confidence interval (0.59 to 0.87)Conclusion: In order to make qualitative demonstration and analysis of hepatobiliary and pancreatic system on MR, both 2D T2 haste sequence in transversal plane and 3D MIP reconstruction are required.

Spectrum of Central Nervous System Anomalies Detected by Fetal Magnetic Resonance Imaging; A 2 Year Study

Background: Magnetic resonance Imaging (MRI) is increasingly used for detailed visualization of the fetus as well as pregnancy structures although ultrasound(US) remains the predominant modality for evaluating disorders related to pregnancy overall. MRI does not have the limitations of US thanks to its multiplanar capability, lack of ionizing radiation, and excellent soft-tissue contrast. The most common indications for fetal MRI are neurological. MRI is commonly used to investigate underlying etiologies of brain abnormalities that are not detected by US. Cortical malformations, heterotopias and anomalies of the corpus callosum are well depicted by MRI. It can confirm the diagnosis of ventriculomegaly or other associated abnormalities not detected by sonography. Posterior fossa abnormalities that can be evaluated by prenatal MRI include Dandy-Walker syndrome, Dandy-Walker variant, mega cisterna magna (> 10 mm), arachnoid cyst and Chiaris malformation type II. Evaluation of the spinal column is important to detect abnormalities such as neural tube defects. Objectives: We intend to investigate the prenatal MRIs performed in our center for frequency of different central nervous system anomalies. Patients and Methods: In a cross sectional retrospective study, from September 2011 to December 2013 pregnant women referring for fetal MRI with suspected anomalies diagnosed in prenatal ultrasound were included in the study. All MRIs were done on a 1.5 T Siemens Avanto Magnet with a 4 channel body coil. Mothers with GA of 20 weeks or above were examined in the right tilt position. Sequences include T2 HASTE, Trufisp images 6 mm thick in axial, coronal and sagittal planes to mothers body. T2 HASTE and Trufisp images were also taken with 4 mm slice thickness relative to specific fetal body part being evaluated. T1 flash images were obtained in at least one plane based on clinical indication. We investigated the available images for any abnormality in central nervous system. Descriptive analysis was done on the collected data to achieve the index of frequency. Results: Most of patients (74%) were referred with primary impression of borderline ventriculomegally on ultrasound. A total of 11 patients out of 60 (18.3%) were found to have CNS anomalies and others were normal neurologically. Detected anomalies were as follows: 3 fetuses had complete agenesis of corpus callosum (27.2%), 2 had partial agenesis of corpus callosum (18.18%), 2 had myelomeningocele (18.18%) and 2 had Dandy-Walker variant (18.18%). Chari II malformation, aqueductal stenosis, tethered cord, schizencephaly and enlarged cisterna magna were anomalies presenting each in one patient (9%). 3 of the patients had concomitant findings. Conclusions: MRI is superior to ultrasound in detection of CNS anomalies which seems to over diagnose some brain anomalies and miss some others. Although most of the patients were provisionally diagnosed with ventriculomegally, the majority of them came as normal. Just 18.3% of fetuses had CNS anomalies with complete agenesis of corpus callosum as the most common finding. Other findings were partial agenesis of corpus callosum, myelomeningocele, Dandy-Walker variant, Chari II malformation, aqueductal stenosis, tethered cord, schizencephaly and enlarged cisterna magna, in order of frequency.

Utilidad de la entero-resonancia magnética en el estudio de la enfermedad de Crohn pediátrica

ObjectiveTo determine the usefulness of MRI enterography for assessing the extension and activity of paediatric Crohn's disease. MRI findings were compared with clinical, biological, endoscopic and other imaging data. Patients and methodsStudies of MRI enterography use in patients younger than 18 years of age were reviewed. Patients received 500-1000mL of polyethylene glycol one hour before examination (1.5-TMR). T2 HASTE sequences with or without fat saturation, T2 true-FISP, T1 with fat saturation, pre- and post gadolinium-enhanced VIBE sequences, and dynamic and diffusion HASTE were acquired. Thickening of the bowel wall, mucosal enhancement, and extra-luminal complications were evaluated. Five MRI patterns (normal, fibrosis, mild, moderate, and severe transmural activity) were defined. Findings were compared with PCDAI scores, inflammatory parameters, and endoscopic and histological results. ResultsTwenty-two studies were reviewed. Optimal intestinal distension was present in 82% of the cases. Mild side effects were observed in 12% of patients. There was a significant relationship between MRI patterns and PCDAI scores (P=.002), sedimentation rate (P=.006) and serum PCR levels (P=.047) and a non-significant relationship with the histology (P=.571). MRI enterography correctly assessed the ileal (80%) and colonic (66%) extension. Extra-luminal complications unrelated to MRI classification (P=.274) were reported in 86.4% of studies. ConclusionsThere was a significant relationship between MRI patterns and PCR, sedimentation rate, and PCDAI scores. MRI enterography showed excellent agreement with ileoscopies, and allowed endoscopically non-accessible areas to be assessed, as well as the diagnosis of extra-luminal complications without irradiation.

The Efficacy of Unenhanced MR Imaging for the Diagnosis of Acute Appendicitis: A Performance Comparison Versus Abdominal Ultrasonography

Purpose: To evaluate the efficacy of unenhanced MR imaging compared to the diagnostic accuracy, advantage, and limitations of abdominal ultrasonography in the diagnosis of acute appendicitis. Materials and Methods: The study included 40 patients suspected of having acute appendicitis and who were subjected to an unenhanced MR image, as well as an abdominal ultrasonography. A T1 FLASH in an axial image, a chemical shift-selective fat suppressed T2 HASTE in an axial image, as well as a T2 HASTE in an axial and coronal image were obtained as unenhanced MR images. The diagnosis was established based on a surgical or clinical follow-up of the unenhanced MR results, which were then statistically compared to the ultrasonographic results. Results: The surgical or clinical follow-up results revealed that 25 patients were positively diagnosed with appendicitis. Of these, 7 patients had symptoms of acute appendicitis with no pathologic diagnoses, whereas the 8 remaining patients were diagnosed with another condition. The sensitivity and accuracy of the unenhanced MR imaging was 92% and 90%, compared to ultrasonography which was 68% and 72.5% accurate, respectively. The differences in sensitivity and accuracy between the two methods were found to be statistically significant (p