high intensity signal
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2021 ◽  
pp. 1-6
Author(s):  
Keisuke Tokunaga ◽  
So Tokunaga ◽  
Kenta Hara ◽  
Masahiro Yasaka ◽  
Yasushi Okada ◽  
...  

OBJECTIVE To test the hypothesis that intraplaque hemorrhage is a predictor of restenosis after carotid artery stenting (CAS), the association between intraplaque high-intensity signal (HIS) on time-of-flight MR angiography (TOF-MRA), as a marker of intraplaque hemorrhage, and restenosis after CAS was assessed in the present observational study. METHODS Consecutive patients who underwent initial CAS for atherosclerotic stenosis in the cervical internal carotid artery in the authors’ department were enrolled. Of these, patients without preprocedural cervical TOF-MRA were excluded. Outcome measures were ≥ 50% restenosis, defined as a peak systolic velocity of > 1.3 m/sec; or occlusion and ≥ 70% restenosis, defined as a peak systolic velocity of > 2.1 m/sec; or occlusion on carotid duplex ultrasound. RESULTS Of 230 consecutive patients who underwent initial CAS, 22 without preprocedural cervical TOF-MRA were excluded. Of the remaining 208 patients (mean age 73 years; 33 women), 46 had intraplaque HIS. Ultrasound follow-up was not performed in 4 patients. The median follow-up duration was 3.2 years (interquartile range 1.7–5.1 years). During the follow-up period, 102 patients had ≥ 50% restenosis and 36 had ≥ 70% restenosis. Intraplaque HIS was significantly associated with increased risk of ≥ 50% restenosis (adjusted hazard ratio 2.18; 95% CI 1.28–3.68) and ≥ 70% restenosis (adjusted hazard ratio 3.12; 95% CI 1.32–7.52). CONCLUSIONS Intraplaque HIS on TOF-MRA was associated with increased risk of restenosis after CAS. The present results indicate that intraplaque hemorrhage is a predictor of restenosis after CAS.


2021 ◽  
pp. 1220-1227
Author(s):  
Yoko Nakayama ◽  
Akira Sugiyama ◽  
Tetsu Yamamoto ◽  
Ryoji Hyakudomi ◽  
Noriyuki Hirahara ◽  
...  

Pyomyositis has recently been recognized as a primary infection of the large skeletal muscles, and it is often accompanied by single or multiple intramuscular abscess formation. Immunocompromised patients, including those with diabetes mellitus, human immunodeficiency virus infection, and cancer, as well as those undergoing chemotherapy, are at a greater risk of developing pyomyositis. A 78-year-old Japanese man with recurrent gastric cancer being treated with chemotherapy presented with sudden-onset pain in his left lower extremity while undergoing a second-line regimen with irinotecan. T2-weighted magnetic resonance imaging (MRI) showed an abnormally high-intensity signal in the left internal and external obturator muscles, a finding consistent with pyomyositis. Following intensive antibiotic treatment, the patient recovered completely and was able to resume chemotherapy with irinotecan. For a patient who developed pyomyositis during chemotherapy for gastric cancer, early diagnosis using MRI followed by administration of timely intensive antibiotic therapy resulted in complete recovery.


2021 ◽  
pp. 424-430
Author(s):  
Koichi Oishi ◽  
Kazuhiro Toyota ◽  
Manabu Shimomura ◽  
Tadateru Takahashi

Castleman’s disease (CD) arising from the hepatoduodenal ligament is extremely rare. A 32-year-old man was referred to a clinic with nausea. He was found to have an abdominal mass by ultrasonography and consulted our hospital for further examination. Computed tomography revealed an equally enhancing mass, 5.2 cm in diameter, adjacent to the duodenum. On magnetic resonance imaging, the mass revealed a slightly iso-intensity signal equal to smooth muscle on T1-weighted imaging, a slightly high-intensity signal on T2-weighted imaging, and a high-intensity signal on diffusion-weighted imaging. Endoscopic ultrasonography showed a well-demarcated hypoechoic mass adjacent to the duodenum. The Doppler echo pattern indicated abundant blood flow. The preoperative diagnosis was a duodenal gastrointestinal stromal tumor. The patient underwent laparotomy and tumor excision. The finding of the intraoperative frozen section was CD. Histologically, the lymph follicles were markedly increased in number throughout the cortex and medulla with vascular proliferation and hyalinization in the intra- or extra-follicles. The germinal centers were atrophic and surrounded by concentrically arranged layers of small lymphocytes. The histological findings were the hyaline vascular variant of CD. If a hypervascular solid mass is detected in the abdomen, CD should be considered in the differential diagnosis.


2021 ◽  
Vol 75 (1) ◽  
pp. 46-50
Author(s):  
Eva Karásková ◽  
Mária Véghová-Velgáňová ◽  
Miloš Geryk ◽  
Vratislav Smolka ◽  
Kamila Michálková ◽  
...  

Posterior Reversible Encephalopathy Syndrome (PRES) is a clinical-neuroradiological entity with acute onset, defined as a vasogenic brain edema associated with neurotoxic impairment. We report the case of an eight-year-old boy with severe ulcerative colitis and celiac disease, who was treated with infliximab and azathioprine. On the 10th day after infliximab administration, a 45-minute unconsciousness developed with generalized convulsions and pupil miosis, accompanied by arterial hypertension. The boy was treated with anticonvulsants and antihypertensives. The state of consciousness improved ad integrum. Magnetic resonance imaging (MRI) of the brain revealed symmetric areas of high-intensity signal involving occipital and fronto-parietal lobes. Lumbar puncture was negative. Repeat MRI, seven days from the onset, showed resolution of the previous changes. The condition was assessed as PRES that developed as a complication of treatment (infliximab, azathioprine) in a patient with active ulcerative colitis. The case indicates a possible risk of developing PRES in patients with uncompensated inflammatory bowel disease, receiving immunosuppressive and/or bio­logical treatment and/or developing arterial hypertension


2021 ◽  
pp. 1-9
Author(s):  
Junlin Lu ◽  
Yahui Zhao ◽  
Mingtao Li ◽  
Li Ma ◽  
Yu Chen ◽  
...  

<b><i>Objective:</i></b> Infarction is one of the most common postoperative complications after surgical revascularization for moyamoya disease (MMD). Increased conspicuity of deep medullary veins (DMVs) on susceptibility-weighted imaging (SWI), known as “brush sign,” could predict the severity of MMD. This study aimed to reveal the features of the “brush sign” in preoperative SWI and to verify its relationship to postoperative infarction. <b><i>Methods:</i></b> Consecutive patients with MMD who had undergone cerebral revascularization surgery were included. Routine preoperative SWI was performed. The “brush sign” was defined according to the number of the conspicuous DMVs &#x3e; 5 detected on SWI. Postoperative infarctions were defined as the high-intensity signal on postoperative DWI images, with or without neurologic deficits. The modified Rankin scale (mRS) was applied to evaluate the prognosis of patients. <b><i>Results:</i></b> In the enrolled 100 hemispheres, 35 were presented with the “brush sign.” Patients with ischemic onset manifestation and previous infarction history tended to present with the “brush sign.” Multivariate analysis showed that the “brush sign” (OR 13.669; 95% CI, 1.747–106.967, <i>p</i> = 0.013) and decreased rCBF (OR 6.050; 95% CI, 1.052–34.799, <i>p</i> = 0.044) were independent risk factors of postoperative infarction. Besides, the “brush sign” showed a significant correlation with a higher mRS score at discharge (<i>p</i> = 0.047). <b><i>Conclusion:</i></b> The findings strongly suggest that the presence of the “brush sign” preoperatively can be a predictor of infarction after surgical revascularization for ischemic MMD. It may contribute to an improved surgical result through focused perioperative management based on appropriate surgical risk stratification.


2021 ◽  
Vol 12 ◽  
pp. 27
Author(s):  
Dimitrios Papadakos ◽  
Spiros Boulieris ◽  
Andreas Theofanopoulos ◽  
Dionysia Fermeli ◽  
Constantine Constantoyannis

Background: Vertebral hemangiomas (VH) are the most common benign vascular neoplasms of the spine. Aggressive VH (AVH) may become symptomatic due to soft-tissue expansion/extraosseous extension into the paraspinal and/or epidural spaces. There are several options for treating painful AVH, including radiotherapy and/or open surgery. Case Description: A 59-year-old male presented with a 2-year history of intermittent back pain and progressive thoracic myelopathy in the past 2 months. MRI revealed a T9 level lesion, with high-intensity signal on both T1 and T2 images and an extraosseous component with significant cord compression. We performed minimally invasive tubular unilateral laminotomy for bilateral decompression of the thoracic spine at the T9 level, followed by bilateral percutaneous vertebroplasty with biopsy. Postoperatively, the pain was immediately relieved, and the myelopathy improved. The biopsy confirmed the diagnosis of a VH. Conclusion: Combining minimally invasive techniques consisting of tubular laminectomy and percutaneous vertebroplasty are safe and effective ways for treating AVHs.


2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
M Leth-Olsen ◽  
G Doehlen ◽  
H Torp ◽  
SA Nyrnes

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Joint Research Committee between St. Olavs Hospital and the faculty of Medicine, NTNU. The Norwegian Association for Children with Congenital Heart Disease Research Foundation, FFHB Background   There is a risk of gaseous- and solid micro embolus formation during transcatheter procedures (CATH) and surgery in children with congenital heart disease (CHD). Silent strokes during surgery or CATH may contribute to neurological impairment. NeoDoppler is a non-invasive ultrasound system based on plane wave transmissions to continuously monitor cerebral blood flow in infants with an open fontanelle. Gaseous- and solid micro embolus passing through the ultrasound beam create High Intensity Transient Signals (HITS) in the Doppler signal.  Purpose We aimed to study the amount of HITS during CATH and surgery in infants using NeoDoppler.  Methods   The NeoDoppler probe operates at a frequency of 7.8 MHz. The frame rate is 300 fps and the beam covers a wide cylindrical area (10/35mm width/depth). The system displays a color M-mode Doppler and a spectrogram. The broad ultrasound beam permits prolonged scanning time of each event as the HITS move through the ultrasound beam. The high framerate and color M-mode allows for tracking of embolies in depth. In this study the NeoDoppler probe was attached to the anterior fontanelle of infants with CHD during CATH (n = 15) and cardiac surgery (n = 13). HITS were defined as high intensity signal creating skewed lines in the color M-mode Doppler moving away or towards the probe (blue/red) with a corresponding high intensity signal in the spectrogram. HITS were grouped into single HITS and HITS with curtain effect. Single HITS were defined as single skewed lines in the color M-mode Doppler and spectrogram. HITS with curtain effect were defined as skewed broad lines or multiple intensity increase lines in the color M-mode Doppler with corresponding intensity increase that filled the entire doppler curve. HITS with curtain effect are believed to represent numerous HITS that could not be separated from each other in the spectrogram. HITS were manually detected in an in-house MatLab application. Results   The study group consisted of 28 infants (17 males) with different CHD who underwent CATH or surgery. The median age and weight was 96 days (range 3-240 days) and 5650 g (range 2400-8085 g). HITS were detected in 13/15 patients during CATH with a total of 392 HITS (Median 12, Range 0-149) and in all patients during surgery with a total of 772 HITS (Median 45, Range 11-150).  The picture shows examples of single HITS (panel A) and HITS with curtain effect (panel B). One can appreciate the embolic trajectory pattern in depth over time in the color M-mode Display.  Conclusion   In this study we found that NeoDoppler enables detection of frequent HITS in patients with CHD undergoing surgery or CATH. NeoDoppler could become a useful tool to guide modifications of procedures, with aim to reduce the risk of silent stroke. However, further studies are needed to validate the technique. Abstract Figure.


2020 ◽  
Vol 21 (6) ◽  
pp. 1980 ◽  
Author(s):  
Atsushi Ogata ◽  
Tomihiro Wakamiya ◽  
Masashi Nishihara ◽  
Tatsuya Tanaka ◽  
Taichiro Mizokami ◽  
...  

(1) Background: Pericytes are involved in intraplaque neovascularization of advanced and complicated atherosclerotic lesions. However, the role of pericytes in human carotid plaques is unclear. An unstable carotid plaque that shows high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) is often a cause of ischemic stroke. The aim of the present study is to examine the relationship between the pericytes in intraplaque neovessels and MRA findings. (2) Methods: A total of 46 patients with 49 carotid artery stenoses who underwent carotid endarterectomy at our hospitals were enrolled. The patients with carotid plaques that were histopathologically evaluated were retrospectively analyzed. Intraplaque hemorrhage was evaluated using glycophorin A staining, and intraplaque neovessels were evaluated using CD34 (Cluster of differentiation) stain as an endothelial cell marker or NG2 (Neuron-glial antigen 2) and CD146 stains as pericyte markers. Additionally, the relationships between the TOF-MRA findings and the carotid plaque pathologies were evaluated. (3) Results: Of the 49 stenoses, 28 had high-intensity signals (TOF-HIS group) and 21 had iso-intensity signals (TOF-IIS group) on TOF-MRA. The density of the CD34-positive neovessels was equivalent in both groups. However, the NG2- and CD146-positive neovessels had significantly higher densities in the TOF-HIS group than in the TOF-IIS group. (4) Conclusion: The presence of a high-intensity signal on TOF-MRA in carotid plaques was associated with intraplaque hemorrhage and few pericytes in intraplaque neovessels. These findings may contribute to the development of new therapeutic strategies focusing on pericytes.


2020 ◽  
Vol 83 (3) ◽  
pp. 271-278
Author(s):  
Chenguang Zhou ◽  
Haixia Fan ◽  
Hao Chen ◽  
Haoyue Wang ◽  
Zuopeng Li ◽  
...  

Objective: The aim of this study was to characterize clinical features, etiologies, and mechanisms of strokes due to bilateral middle cerebellar peduncle infarction (BMCPI). Methods: Cases diagnosed as BMCPI in our hospital were retrieved, and a literature review was performed. Data on clinical features and brain MRI were obtained. Extracranial and intracranial segments of the vertebrobasilar artery were assessed by using digital subtraction angiography, magnetic resonance angiography, or computed tomography angiography. Results: Thirteen cases (11 men and 2 women) of BMCPI were identified. A high-intensity signal of diffusion-weighted imaging sequence involving the bilateral middle cerebellar peduncle was observed in all patients. Most patients experienced vertigo, dysarthria, ataxia, and hearing disorders. Eleven of these cases were classified as large artery atherosclerosis, one as traumatic vertebral artery (VA) dissection, and one as giant cell arteritis. Conclusion: BMCPI is a rare cerebrovascular disease characterized by vertigo, ataxia, and dysarthria, which may also be accompanied by a hearing deficit or clinical signs of brainstem damage. BMCPI may be associated with hypoperfusion secondary to occlusive disease of the bilateral VA or proximal basilar artery.


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