195 research outputs found
Infantile Sturge-Weber Syndrome with Hypointense White Matter on T2-weighted MR images
The implication of hypointense white matter on T2- weighted MR images in infants with Sturge-Weber syndrome is a subject of recent controversy. We report a case of infantile Sturge-Weber syndrome with decreased white matter signal on T2-weighted MR images. This hypointensity may reflect accelerated myelination and/or increased deoxyhemoglobin in capillaries and dilated deep medullary veins
Quadruple coaxial catheter system on transvenous embolization for dural arteriovenous fistula
Background: Although transvenous embolization (TVE) is an effective method for treating dural arteriovenous fistula (AVF), directing the catheter to the lesion site is difficult.Objective: We report on the utility of a quadruple coaxial catheter system for TVE.Materials and methods: The quadruple catheter system comprised a 6 Fr guiding sheath, 6 Fr guiding catheter, 4 Fr intermediate catheter, and a regular microcatheter. The system was utilized in 27 consecutive dural AVF cases treated with TVE. In this study, we reviewed our experience with this system, including the theory, method of use, and complications.Results: Stenosis or obstruction of the vascular access was identified in 12 cases. The catheter could not reach to the lesion in three cases of cavernous sinus (7.4%); therefore, transarterial embolization was employed. Angiographic results revealed that the cases consist of total occlusion (n = 16, 59.5%), subtotal (n = 10, 37.0%), and partial occlusion (n = 1, 3.7%). Complete resolution or improvement of symptoms was observed in 23 patients (85.2%), no improvement of symptoms was observed in three patients (7.4%), and deterioration of symptoms was observed in one patient (3.7%). Venous perforation occurred in one patient without any neurological deficit. The catheter system provided access to the lesion and provided stability during the mechanically demanding process navigating the catheter and placing the coils.Conclusion: We determined that the quadruple coaxial system was safe and efficient for TVE for dural AVF
Extremely Rare Breakdown of the Moyamoya Vessels Resulting in Intraventricular Hemorrhage after Direct Bypass Surgery in a Pediatric Patient with Moyamoya Disease
Revascularization surgery is established for both ischemic and hemorrhagic moyamoya disease (MMD), although hemorrhagic complication is a serious problem especially in adult MMD patients showing postoperative hyperperfusion. Herein, we present an extremely rare case with pediatric MMD showing intraventricular hemorrhage the day following direct bypass surgery, possibly due to a breakdown of the terminal branch of well-developed perforators working as moyamoya vessels. Clinicians should consider this rare complication after bypass surgery for MMD regardless of preoperative hemodynamics or patient age
Amide proton transfer MRI differentiates between progressive multifocal leukoencephalopathy and malignant brain tumors: a pilot study
Background: Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nerve system caused by the John Cunningham virus. On MRI, PML may sometimes appear similar to primary central nervous system lymphoma (PCNSL) and glioblastoma multiforme (GBM). The purpose of this pilot study was to evaluate the potential of amide proton transfer (APT) imaging for differentiating PML from PCNSL and GBM. Methods: Patients with PML (n = 4; two men; mean age 52.3 ± 6.1 years), PCNSL (n = 7; four women; mean age 74.4 ± 5.8 years), or GBM (n = 11; 6 men; mean age 65.0 ± 15.2 years) who underwent APT-CEST MRI between January 2021 and September 2022 were retrospectively evaluated. Magnetization transfer ratio asymmetry (MTRasym) values were measured on APT imaging using a region of interest within the lesion. Receiver operating characteristics curve analysis was used to determine diagnostic cutoffs for MTRasym. Results: The mean MTRasym values were 0.005 ± 0.005 in the PML group, 0.025 ± 0.005 in the PCNSL group, and 0.025 ± 0.009 in the GBM group. There were significant differences in MTRasym between PML and PCNSL (P = 0.023), and between PML and GBM (P = 0.015). For differentiating PML from PCNSL, an MTRasym threshold of 0.0165 gave diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of 100% (all). For differentiating PML from GBM, an MTRasym threshold of 0.015 gave diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 90.9%, 80.0%, and 100%, respectively. Conclusion: MTRasym values obtained from APT imaging allowed patients with PML to be clearly discriminated from patients with PCNSL or GBM
Quantitative Chemical Exchange Saturation Transfer Imaging of Amide Proton Transfer Differentiates between Cerebellopontine Angle Schwannoma and Meningioma: Preliminary Results
Vestibular schwannomas are the most common tumor at the common cerebellopontine angle, followed by meningiomas. Differentiation of these tumors is critical because of the different surgical approaches required for treatment. Recent studies have demonstrated the utility of amide proton transfer (APT)-chemical exchange saturation transfer (CEST) imaging in evaluating malignant brain tumors. However, APT imaging has not been applied in benign tumors. Here, we explored the potential of APT in differentiating between schwannomas and meningiomas at the cerebellopontine angle. We retrospectively evaluated nine patients with schwannoma and nine patients with meningioma who underwent APT-CEST MRI from November 2020 to April 2022 pre-operation. All 18 tumors were histologically diagnosed. There was a significant difference in magnetization transfer ratio asymmetry (MTRasym) values (0.033 ± 0.012 vs. 0.021 ± 0.004; p = 0.007) between the schwannoma and meningioma groups. Receiver operative curve analysis showed that MTRasym values clearly differentiated between the schwannoma and meningioma groups. At an MTRasym value threshold of 0.024, the diagnostic sensitivity, specificity, positive predictive value, and negative predictive values for MTRasym were 88.9%, 77.8%, 80.0%, and 87.5%, respectively. Our results demonstrated the ability of MTRasym values on APT-CEST imaging to discriminate patients with schwannomas from patients with meningiomas
Long-term follow-up of endovascular coil embolization for cerebral aneurysms using three-dimensional time-of-flight magnetic resonance angiography.
OBJECTIVES: As endovascular treatment becomes more prevalent, aneurysm recurrence from neck remnants, recanalization, incomplete obliteration and bleeding remain major concerns. In the current analysis, we attempted to identify factors related to disease progression and clinical outcome in patients treated with coil embolization. METHODS: This study included 58 patients who underwent endovascular coil embolization for treatment of intracranial aneurysm. The result of embolization was evaluated with three-dimensional time-of-flight magnetic resonance angiography (TOF MRA) and classified as a complete occlusion, a residual neck (minor, central and marginal types), a residual dome (central and marginal types). Patients were followed up clinically and radiologically. Statistical analyses were performed to establish factors that influenced the occurrence of adverse events such as recurrence of aneurysm. RESULTS: Overall, the complete occlusion rate was 18.8%, the occurrence of a residual neck was 67.2%, and the residual dome rate was 14.1%. The mean clinical follow-up was 31.2 months. Recurrences were found in 18 aneurysms, and major recurrences were retreated with coiling or surgery. The post-treatment study revealed that the marginal-type aneurysm filling has a significant impact on outcome. Thus, perianeurysmal edema was correlated with recurrence of the aneurysm. CONCLUSIONS: Three-dimensional TOF MRA was a sensitive tool for visualizing residual filling of embolized aneurysm and is useful for long-term follow-up of patients
Three-Dimensional Anisotropy Contrast MRI and Functional MRI of the Human Brain: Clinical Application to Assess Pyramidal Tract in Patients with Brain Tumor and Infarction
We describe and evaluate the findings of three-dimensional anisotropy contrast MR axonography (3DAC MRX) and functional MRI (fMRI) in brain tumor and infarction. We obtained diffusion-weighted images (DWI) in 28 patients including 23 brain tumors and 15 acute infarctions located in or near pyramidal tract. Three anisotropic DWIs were transformed into graduations color-coded as red, green or blue, and then composed to form a combined color 3DAC MRX. We also performed functional MRI in 7 of the 28 patients and compared with cortical mapping of 3DAC MRX. 3DAC MRX with 23 brain tumors showed that the ipsilateral pyramidal tract was either discontinuous due to impaired anisotropy (n=8) or compressed due to mass effect (n=15). In 10 patients of acute infarction with motor impairment, pyramidal tract involvement was visually more conspicuous on 3DAC MRX compared to standard DWI. On functional MRI, hand motor activation was observed between blue vertical directional colors of pre- and post central gyrus. In conclusion, 3DAC MRX is a new noninvasive approach for visualization of the white matter neuronal tract and provides the information concerning pyramidal tract involvement
Recurrence of the cavernous sinus dural arteriovenous fistula at adjacent sinuses following repeated transvenous embolizations: case report and literature review.
We present a unique case of a cavernous sinus (CS) dural arteriovenous fistula (DAVF), which recurred at adjacent sinuses following repeated transvenous embolizations (TVEs). A 68-year-old woman presented with progressive left conjunctival chemosis and diplopia. Cerebral angiography revealed a left CS DAVF, which was completely obliterated by TVE via the left inferior petrosal sinus (IPS). Two years later, the DAVF recurred in the left IPS, and again in the left sigmoid sinus (SS) 3 years after the initial treatment in spite of a second TVE. Moreover, the left SS and the left internal jugular vein, which had been previously stenotic, had been occluded. The third TVE resulted in the complete obliteration of the SS DAVF. CS DAVFs may recur at adjacent sinuses even after complete obliteration by TVE. Careful follow-up is necessary to check for the recurrence of DAVFs, especially in cases with venous flow changes, such as sinus occlusion, following endovascular treatment.The original publication is available at www.springerlink.co
A case of iliac artery injury treated by covered stent during carotid artery stenting
Here we describe a case of iliac artery injury during carotid artery stenting (CAS) treated by covered stent. A 74-year-old man underwent CAS for asymptomatic right carotid artery stenosis. Under local anesthesia, the right common femoral artery was punctured and an 8 Fr long sheath introducer was placed. However, the sheath kinked because the iliac artery was tortuous. We introduced the stylet to the sheath again and tried to extend the kinking. It failed, and the arterial dissection was identified at the lateral iliac artery. The kink was extended with triple coaxial system, i.e. guidewire, coaxial catheter, and a guiding catheter; CAS was performed with distal filter protection. Before removal of the sheath, the right iliac artery was examined, and extraversation of the contrast medium was observed. The balloon catheter was placed to the lesion and dilated for the hemostasis. However, it failed, and the covered stent was placed subsequently. Although blood tests revealed anemia and CT showed retroperitoneal hematoma after the treatment, further complication did not occur. Treatment with covered stent for the vessel injury was effective
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