Clinical characteristics of 42 cases of spontaneous intracranial hypotension with cerebrospinal leakage / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To review the clinical characteristics of spontaneous intracranial hypotension (SIH) with cerebrospinal fluid (CSF) leakage.</p><p><b>METHODS</b>Clinical data of 42 SIH patients with cerebrospinal leakage, whose diagnosis met the criteria of the International Headache Classification, were retrospectively reviewed. The patients were divided into short (n=27) and long (n=15) course groups. The clinical data and imaging features were compared between two groups.</p><p><b>RESULTS</b>Thirty-nine patients (92.9%) had orthostatic headache. Compared with the short course group, the frequency of headache were significantly lower in patients with long disease duration (80% vs 100%, P =0.040); the ratio of high CSF opening pressure (>=60.0 mm H2O), the average CSF opening pressure, and the frequencies of subdural hematoma were higher in long course group than those in short course group [60.0% vs 20.8%, (64.7±42.1) vs (40.0±33.8)mm H2O, and 50.0% vs 11.6%; P=0.019, 0.038 and 0.018, respectively]. Forty-two patients underwent CT myelography;definite focal CSF leakage sites were found in all patients and multiple sites of CSF leakage in 38 patients.</p><p><b>CONCLUSION</b>All SIH do not necessarily show the typical clinical manifestations, and cranial MRI and CT myelography are helpful in the diagnosis. Because of higher risk of subdural hemorrhage, patients with long disease duration require active intervention.</p>

Differentiation of white and red thrombus with magnetic resonance imaging: a phantom study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>An early identification of the composition of arterial thrombus may have diagnostic, therapeutic, and prognostic implications. The variation of magnetic resonance (MR) signal intensity between white and red thrombi, especially in the susceptibility sensitive MR sequence, remains unknown. Our research was to evaluate the feasibility of MRI in differentiating of white and red thrombi with a phantom study.</p><p><b>METHODS</b>A total of 12 red and 12 white thrombi were prepared with the venous blood. Examination of the phantom was completed using a 3.0T MR unit, including fluid attenuated inversion recovery (FLAIR) T1, T2-weighted imaging (T2WI), FLAIR T2, T2 gradient echo (T2 GRE) imaging, and susceptibility weighted angiography sequences (SWAN). MR signal intensity patterns of the thrombi were objectively classified as hyperintensity, isointensity and hypointensity, compared with the background agar. The volume of thrombus was calculated and correlated with its signal intensity.</p><p><b>RESULTS</b>For white thrombi, 11/12 clots showed hyperintensity and 1/12 showed isointensity in FLAIR T1 images. In T2WI, 6/12 clots showed hyperintensity, 3/12 isointensity, and 3/12 hypointensity. In FLAIR T2, 8/12 clots showed hyperintensity and 4/12 showed isointensity. In T2 GRE, 3/12 clots showed hyperintensity and the remaining 9/12 clots showed isointensity. In SWAN, 5/12 clots demonstrated hyperintensity and 7/12 isointensity. For the red thrombus, 12/12 clots demonstrated hyperintensity in FLAIR T1, T2WI, and FLAIR T2 sequences. In T2 GRE and SWAN sequences, 3/12 clots displayed hypointensity and the remaining 9/12 clots showed slight hyperintensity. Thrombi with hypointensity displayed in T2 GRE and SWAN sequences were significantly larger than those with hyperintensity.</p><p><b>CONCLUSIONS</b>Differentiation of white and red thrombi with conventional MR sequence is unreliable, because both kinds of thrombi do not possess unique signal intensity features in these sequences. Red thrombus may or may not show hypointensity in the susceptibility sensitive MR sequences, depending on its size and time course.</p>

Prevalence of nerve-vessel contact at cisternal segments of the oculomotor nerve in asymptomatic patients evaluated with magnetic resonance images / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Some studies indicated that cases of idiopathic oculomotor nerve palsy can be explained by vascular compression of the oculomotor nerve. Vascular contact with or compression to the cisternal segment of the oculomotor nerve has been reported frequently in asymptomatic individuals. In this study, we retrospectively analyzed the relationship between the oculomotor nerve's cisternal segment and adjacent arteries in asymptomatic patients and the prevalence of this occurrence via magnetic resonance imaging (MRI).</p><p><b>METHOD</b>MRI of bilateral oculomotor nerves in 93 asymptomatic patients were reviewed. The oculomotor nerve-artery relationship was evaluated and classified from levels 1 to 3, representing the degrees of contact on oblique transverse and oblique sagittal reconstructed MRI. Prevalence of the nerve-artery relationship at each level was described. The correlation between the nerve-vessel relationship (levels) and the age was analyzed by Spearman's rank correlation analysis.</p><p><b>RESULTS</b>Cisternal segment of the oculomotor nerve did not have contact with any artery (level 1) in 27.4% (51/186) nerves. One hundred nerves made contact with at least one artery (level 2), but their shapes or configurations were not changed; 35 nerves (18.8%) were displaced or distorted due to artery compression (level 3). The posterior cerebral artery had the greatest incidence of making contact with or compressing the cisternal segment of the oculomotor nerve (58.1%). No significant correlation between nerve-vessel relationship (levels) and the age was found in this study.</p><p><b>CONCLUSIONS</b>Whether oculomotor nerve contact with or compression by one or more arteries is of high prevalence in asymptomatic individuals as evidenced by MRI examination. There is no correlation with individual age. Discretion should be used when making an etiological diagnosis of vascular compression for patients with oculomotor nerve palsy. Further investigation of other causes is warranted.</p>

Imaging diagnosis of skull epidermoid cyst:analysis of four cases / 中华放射学杂志

Objective To study the CT and MR imaging features of skull epidermoid cyst. Methods CT and MR findings of 4 cases of pathologically proved skull epidermoid cyst were analyzed and correlated with operative and pathologic reports.Results CT and MR appearances of skull epidermoid cyst were as follows:(1)crater-form or scalloping deossification with sclerotic border and fatty density focus was detected on CT.(2)The lesions were isointense to hypointense relative to normal white matter in T1-weighted image,prominent hyperintense in T_2-weighted image,mild to moderate hyperintense in diffusion-weighted imaging(DWI),and isointense to hypointense in apparent diffusion coefficient(ADC) map on MR.Proton MRS revealed lactate(Lac)peaks at 1.3 ppm and amino acids(AAs)at 0.9 ppm. (3)No enhancement was found in substance region of all tumors on both enhanced CT and enhanced MR examinations.Conclusion CT and MR appearances of skull epidermoid cyst have unique features which are very helpful in the diagnosis of skull epidermoid cyst.

Three-dimensional reconstruction of brain surface anatomy:technique comparison between flash and diffusion-weighted imaging / 中华放射学杂志

Objective To compare two methods 3D flash and diffusion-weighted images(DWI)in reconstructing the brain surface anatomy,and to evaluate their displaying ability,advantages,limitations and clinical application.Methods Thrity normal cases were prospectively examined with 3 D flash sequence and echo-planar DWI.Three-dimensional images were acquired with volume-rendering on workstation.Brain surface structures were evaluated and scored by a group of doctors.Results Main structures of brain surface were clearly displayed on three-dimensional images based on 3D flash sequence.Average scores were all above 2.50.For images based on DWI,precentral gyrus,postcentral gyrus,superior parietal lobule, superior frontal gyrus,precentral sulcus,central sulcus,postcentral sulcus,intraparietal sulcus and superior frontal sulcus were best shown with average scores between 2.60-2.75,However,supramarginal gyrus, angular gyurs,middle frontal gyrus,inferior frontal gyrus,superior temporal gyrus,lateral sulcus,inferior frontal sulcus could not be well shown,with average scores between 1.67-2.48.Middle temporal gyrus, inferior temporal gyrus,superior temporal sulcus and inferior temporal sulcus can only get scores from 0.88 to 1.27.Scores of images based on 3D flash were much higher than that based on DWI with distinct differentiations,P values were all below 0.01.Conclusion Three-dimensional images based on 3D flash can really display brain surface structures.It is very useful for anatomic researches.Three-dimensional reconstruction of brain surface based on DWI is a worthy technique to display brain surface anatomy, especially for frontal and parietal structures.