Lactate peak on brain MRS in children with syndromic mitochondrial diseases.

BACKGROUND: Brain magnetic resonance spectroscopy (MRS) has been reported to be a valuable noninvasive tool in the diagnosis of some rare diseases. In this study, our aim was to assess lactate peak on single-voxel proton MRS in children with syndromic mitochondrial diseases (MDs). METHODS: From March 2004 to November 2010, 14 patients who were diagnosed with syndromic MDs underwent single-voxel proton MRS examination. The volume of interest was positioned on axial magnetic resonance imaging (MRI), and voxels were sampled using short (35 milliseconds), intermediate (144 milliseconds), or long (288 milliseconds) echo times for determination of lactate at 1.33 parts/million. RESULTS: Twelve of fourteen patients (85.7%) exhibited lactate peaks on the initial single-voxel proton MRS, and all of them showed abnormal MRI findings. The correlations of lactate level in blood and lactate peak on single-voxel proton MRS were inconsistent. Among the 12 patients, eight (66.7%) had corresponding elevated levels of blood lactate, and four (33.3%) had normal levels of blood lactate. Compared with a positive rate of 85.7% for patients with lactate peaks on the single-voxel proton MRS, the positive rates for diagnosing syndromic MDs by using electron microscopic examination of muscle biopsy, oral glucose lactate stimulation test, and blood lactate level were 100%, 91.7%, and 71.4%, respectively. CONCLUSION: Lactate acquisition on single-voxel proton MRS provides a noninvasive and complementary tool for the diagnosis of syndromic MDs, especially in children with abnormal signal changes on the brain MRI or a normal blood lactate level.

Angioplasty as the first-line therapeutic option for venous hypertension with outlet obstruction of dural sinus.

We describe a nonconventional endovascular approach to the treatment of pseudotumor cerebri with venous outlet stricture or obstruction. In three patients presenting with acute visual loss, angiograms showed sinus occlusion and stasis of contrast material, with an increased pressure gradient in the venous system. We used venous sinus angioplasty as the first therapeutic option. This treatment was effective, and symptoms and signs of all three patients subsided quickly. In our initial and limited experience, sinus balloon angioplasty appeared to be a good first-line treatment for patients with pseudotumor cerebri, sinus outlet obstruction and acute vision loss. We prefer to use sinus stent placement as a second-line option when initial attempts are unsuccessful, especially in pediatric and young-adult patients, as illustrated in our cases.

Cerebral sinovenous thrombosis. Neuroimaging diagnosis and clinical management.

SUMMARY: Cerebral sinovenous thrombosis (CSVT) is an uncommon disorder that affects the dural venous sinus and cerebral vein. In our study, thirty- four patients were examined. Pre and/or post contrast-enhanced CT was done in 28 patients. MRI studies were done in 24 patients. 2-D TOF MR venography (MRV) and contrast-enhanced MRV (CEMRV) were done in 19 cases. Digital subtraction angiography (DSA) was done in 18 patients. Sixteen patients received systemic intravenous heparinization, and 12 received endovascular thrombolytic treatment with urokinase combined with anticoagulant therapy. Neuroimages of CSVT can be acquired by direct visualization of the thrombus within the dural sinus or by parenchymal changes secondary to venous occlusion. As there are some pitfalls to MRI in the diagnosis of CSVT, the combination of MRI and MRV is now the gold standard in the diagnosis of CSVT. Usually, accuracy can be improved by applying 2-D TOF MRV and CE MRV. Furthermore, the source image of MRV is critical in differentiating between normal sinus variations and diseased ones. DSA is the best tool for demonstrating dynamic intracranial circulation in CSVT and mostly is used for endovascular treatment. Systemic intravenous anticoagulant therapy with heparin is accepted as a first line treatment. Except for clinical manifestations after systemic heparinization, abnormal MR findings of parenchymal change can be used to determine when to initiate thrombolytic treatment. Endovascular therapy can be finished at the antegrade flow within the dural sinus and continuous anticoagulation is sufficient to facilitate clinical improvement. Clinical suspicion and excellent neuroimaging are crucial in making the diagnosis of CSVT. Proper management with anticoagulants and/or endovascular thrombolytic therapy is mandatory in preventing propagation of the thrombosis and improving the clinical outcome.

CT angiography and MR angiography in the evaluation of carotid cavernous sinus fistula prior to embolization: a comparison of techniques.

BACKGROUND AND PURPOSE: This study compared CT angiography (CTA), MR angiography (MRA), and digital subtraction angiography (DSA) in elucidating the size and location of carotid cavernous sinus fistulas (CCFs) before embolization treatment. METHODS: This was a retrospective study of 53 patients with angiographically confirmed CCF. All patients underwent pre- and postcontrast-enhanced CTA and DSA, and 50 patients also underwent MRA. Two neuroradiologists rated detectability of the fistula tract as "good," "moderate," or "poor" in source images obtained by using each procedure. The chi(2) test was used to compare the imaging modalities with respect to their ability to detect fistulas. RESULTS: CTA did not differ significantly from DSA (P = .155), and both CTA (P = .001) and DSA (P = .007) performed significantly better than MRA in the population as a whole. Differences in performance among the methods, however, depended upon the segmental location of the fistula along the internal carotid artery (ICA). CTA and MRA were similar in detection of CCFs in patients with a fistula at segment 3. CTA significantly outperformed MRA in patients with a fistula at segment 4, who accounted for approximately half of the population. CONCLUSIONS: CTA source imaging has proved itself as useful as DSA for detecting CCFs. Of the 2 noninvasive techniques, CTA performed better than MRA in the population as a whole and in most patients whose fistula was located at segment 4 or 5 of the ICA.