Evrim Ozmen

Evaluation of spontaneous third ventriculostomy by three-dimensional sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) sequence by 3 T MR imaging: Preliminary results with variant flip-angle mode

PURPOSE This prospective study aimed to evaluate the use of three-dimensional sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) in the diagnosis of spontaneous third ventriculostomy (STV) and to compare it with phase-contrast cine magnetic resonance imaging (PC-MRI). METHODS PC-MRI and 3D-SPACE images were obtained in 15 patients with hydrocephalus for evaluation of STV as well as in 10 control cases. The presence of STV was evaluated visually by two experienced radiologists on both PC-MRI and 3D-SPACE images, and the results were statistically compared. RESULTS There was a strong correlation between PC-MRI and SPACE scores for both readers (correlation coefficient [r]=0.784; P=0.001). There was also a good correlation between PC-MRI scores and consensus-based results. Interobserver reliabilities were strong for all STV scores. In addition, there was excellent correlation between 3D-SPACE scores and consensus-based results (first readers kappa value: 0.87; second readers kappa value: 1). CONCLUSION 3D-SPACE can provide morphological-physiological information for the evaluation of STV with no need for additional PC-MRI analysis or other sequences. As a non-invasive test, it can also be included among the first line of choices of MRI sequences for patients with obstructive hydrocephalus.

Platelet activity indices in patients with deep vein thrombosis.

Background: Extensive research has been performed regarding the association between platelet activity indices and various cardiovascular disorders. Less clear data, however, are present between these indices and deep vein thrombosis (DVT). Aim: The aim of this study was to investigate the association between platelet activity indices and DVT in a relatively large population. Methods: Mean platelet volume (MPV), mean platelet mass (MPM), and mean platelet component (MPC) were measured by an autoanalyzer in a total of 203 patients with DVT and the results were compared with 210 age- and sex-matched controls without DVT. Results: There were significant differences between the study and control groups in MPV (8.6 ± 1.3 fL vs 7.9 ± 0.5 fL [95% CI −0.82 to −0.44], P < .001, respectively), MPM (2.2 ± 0.3 pg vs 2.0 ± 0.1 pg [95% CI −0.20 to −0.11], P < .001, respectively), and MPC (24.9 ± 3.2 g/dL vs 26.3 ± 1.6 g/dL [95% CI 0.91 to 1.89], P < .001, respectively). These 3 platelet activity indices were also found to be significant predictors of the presence of DVT (all Ps < .001). Conclusion: In patients with DVT, the presence of DVT was closely associated with increased platelet activation. The MPV, MPM, and MPC may identify patients requiring aggressive antiplatelet treatment.

Radiologic manifestations of colloid cysts: a pictorial essay.

Colloid cysts are among rare benign tumours of the third ventricle. Although the most frequent symptoms are headache and syncope, arrest hydrocephalus or sudden death could appear with colloid cysts. The aim of this pictorial essay was to increase awareness of the clinical presentation, computed tomography (CT) and magnetic resonance (MR) imaging spectrum, and treatment options of the colloid cysts. The data of 11 patients with histopathologically and/or clinically proven colloid cyst were analysed, retrospectively; and the neuroradiologic appearances of the cysts were evaluated. The CT and MR appearance of colloid cysts may change, depending on the viscosity or the cholesterol content of the cysts. However, the cystic content is the most important factor that could affect the success of treatment. Cysts that are especially rich in protein and cholesterol tend to be hyperdense on CT, hypointense on T2-weighted sequences and hyperintense on T1-weighted sequences. These cysts are viscous, and the success of aspiration is significantly low. In the diagnosis and evaluation of small-sized cysts that have an ingredient similar to cerebrospinal fluid, 3-dimensional sequences might be useful. The radiologic appearances of colloid cysts could play an important role in directing these patients to alternative surgical modalities, including resection.

Assessment of third ventriculostomy patency with the 3D-SPACE technique: a preliminary multicenter research study

OBJECT The goal of this study was to determine the value of the 3D sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) technique in the evaluation of endoscopic third ventriculostomy (ETV) patency. METHODS Twenty-six patients with ETV were examined using 3-T MRI units. Sagittal-plane 3D-SPACE with variant flip-angle mode, 3D T1-weighted (T1W), and 3D heavily T2-weighted (T2W) images were obtained with isotropic voxel sizes. Also, sagittal-axial plane phase-contrast cine (PC)-MR images were obtained. The following findings were evaluated: diameters of stoma and third ventricle, flow-void sign on 3D-SPACE and PC-MR images, integrity of the third ventricle on heavily T2W images, and quantitative PC-MRI parameters of the stoma. Obtained sequences were evaluated singly, in combination with one another, and all together. RESULTS The mean area, flow, and velocity values measured at the level of stoma in patients with patent stoma were significantly higher than those measured in patients with closed stoma (p < 0.05). There was significant correlation among PC-MRI, 3D-SPACE, and 3D heavily T2W techniques regarding assessment of ETV patency (p < 0.001). The 3D-SPACE technique provided the lowest rate of ambiguous results. CONCLUSIONS The 3D-SPACE technique seems to be the most efficient one for determination of ETV patency. The authors suggest the use of 3D-SPACE as a stand-alone first-line sequence in addition to routine brain MRI protocols in assessing patients with ETV, thereby decreasing scan time and reserving the use of a combination of additional sequences such as PC-MRI and 3D heavily T2W images in suspicious or complex cases.

The impact of share wave elastography in differentiation of hepatic hemangioma from malignant liver tumors in pediatric population

OBJECTIVE In children it is crucial to differentiate malignant liver tumors from the most common benign tumor, hepatic hemangiomas since the treatment strategies are quite different. We aimed to evaluate the efficiency of shear wave elastography (SWE) technique in differentiation of malignant hepatic tumors and hepatic hemangiomas. METHODS Twenty patients with hepatic tumor were included in our study. Two radiologists performed SWE for 13 patients with malignant hepatic tumors including hepatoblastoma (n=7), hepatocellular carcinoma (n=3), metastasis (n=2), embryonal sarcoma (n=1) and 7 patients with hepatic hemangioma. All of our patients were between the age of 1 and 192 months (mean age: 56.88 months). Receiver operating characteristic analysis was achieved to evaluate the diagnostic accuracy of SWE and to determine the optimal cut-off value in differentiation hepatic hemangioma from malignant hepatic tumors. RESULTS The mean SWE values (in kPa) for the first observer were 46.94 (13.8-145) and 22.38 (6.6-49.6) and those for the second observer were 57.91 (11-237) and 23.87 (6.4-57.5), respectively for malignant hepatic tumors and hepatic hemangiomas. The SWE values of malignant hepatic tumors were significantly higher than those of hepatic hemangioma (p=0.02). The inter-observer agreement was almost perfect (0.81). The area under the receiver operating characteristic curve of SWE for differentiating the hepatic hemangioma from malignant hepatic tumors was 0.77 with a sensitivity of 72.7% and a specificity of 66.7% at a cutoff value of 23.62 with 95% confidence interval. CONCLUSION Shear wave elastography can be helpful in differentiation of malignant hepatic tumors and hepatic hemangioma.

A novel biphasic oral contrast solution for enterographic studies.

Purpose To compare the efficacy and patients’ tolerance of a new mixed biphasic oral contrast solution with routine biphasic oral contrast agent in magnetic resonance (MR) enterography (MRE). Materials and Methods Thirty-seven patients (group 1) had MRE with the new mixture, whereas 14 patients (group 2) had MRE with biphasic oral contrast agent (lactulose). Magnetic resonance enterography images were evaluated by 2 experienced radiologists. Each intestinal segment was evaluated for luminal distension (LD), distinction from the surrounding tissue (wall conspicuity), and the confidence of radiologist for evaluation of the specified segment (radiological evaluation confidence). Comparisons between the 2 groups were performed using the Mann-Whitney U test. Interrater and intrarater agreement values were obtained. In addition, patients’ acceptability and tolerance were assessed. Results The new mixture was more effective than the oral contrast agent used in group 2 for LD, wall conspicuity, and radiological confidence. The values of interrater and intrarater agreement in scoring LD, wall conspicuity, and radiological confidence were generally moderate. Conclusion Our new mixture allowed good-quality enterographic images, and this solution was well tolerated by patients. In addition, this mixture is useful for evaluation of small bowels and colonic segments. We suggest the use of it for enterographic examinations.

Giant dilatations of virchow-robin spaces in the midbrain. MRI aspects and review of the literature.

Virchow-Robin spaces are lesions often seen in the brain parenchyma but their etiopathogenesis remains unsettled. Giant Virchow-Robin spaces placed in the midbrain are extremely rare. We describe three patients with a diagnosis of giant Virchow-Robin spaces in the midbrain, and their clinical and radiologic findings. We reviewed the literature in terms of the etiopathology, anatomic and radiologic appearance and differential diagnosis of the giant Virchow-Robin spaces. The diagnostic role of the high Tesla magnetic resonance devices and new sequences techniques such as three dimensional isotropic acquisition and diffusion tensor imaging were also evaluated in this case series.

Desmoid Tumor Associated With Familial Adenomatous Polyposis: Evaluation With 64-Detector CT Enterography

Desmoid tumors (DTs) are benign tumors which are not seen very often, and most of the radiologists and clinicians do not know the characteristics of them very well. Correct and early diagnosis of DTs is important for decreasing mortality and morbidity. Computed tomography enterography (CTE) is a new modality for small bowel imaging which combines the improved spatial and temporal resolution of multidetector computed tomography (CT) with large volumes of ingested enteric contrast material to permit evaluation of the small bowel wall and lumen and also the entire abdomen. We report a familial adenomatous polyposis (FAP) patient with localized mesentery and abdominal wall DTs. We showed the exact location of the DTs and their relation with the small bowel by CTE. In conclusion, CTE is a useful technique for DT localization, the degree of extension and invasion to local structures, presence of partial and complete small bowel obstruction, and the relationship of the tumors with vasculature and whether ischemia has occurred as a result or not.

Magnetic resonance enterography findings of chronic radiation enteritis

Abstract The diagnosis of chronic radiation enteritis (CRE) is considerably challenging both for clinicians and radiologists. The aim of this study was to evaluate the role of magnetic resonance enterography (MRE) in the diagnosis of CRE. To the best of our knowledge, there are no reports on the role of MRE in the diagnosis of CRE specifically. In this report, we present MRE findings of 4 patients with CRE. The most important factors in CRE diagnosis are the clinical findings and medical history, but focal abnormal bowel loop in the region of a known radiation field is the most important information. This abnormal loop is generally located in the distal ileum as present in our patients. Other associated findings helpful for the diagnosis are small bowel thickening, contrast material enhancement in a long segment, mesenteric stranding and luminal narrowing. MRE can be sufficient and useful in the diagnosis of CRE and for treatment planning, especially in patients with significant comorbidities who have had radiotherapy in the past. Adding MRE into the diagnostic algorithm can be helpful in post-radiotherapy patients with acute/subacute gastrointestinal symptoms.

Magnetic resonance imaging of vulvar dermatofibrosarcoma protuberans - report of a case.

Abstract Background. Dermatofibrosarcoma protuberans (DFSP) of the vulva is a rare low-grade soft tissue sarcoma. Magnetic resonance imaging (MRI) findings of vulvar DFSP were essentially unreported in the literature. Case report. We report a DFSP of vulva with its clinical, histological and MRI features. As far we know this is the first case of histologically confirmed vulvar DFSP presenting with MR images. The diagnosis of DFSP is usually made by histopathologic and clinical findings. Conclusions. MRI is useful both for the diagnosis of DFSP and following up the patients since it has high soft tissue resolution and no risk of radiation exposure. With MRI the relation to the adjacent anatomical structures, extension and depth of the tumour and possible lymph node involvement can also be demonstrated.