lesion growth
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Author(s):  
Carlos Michel Albuquerque Peres ◽  
Alyce Castro de Brito ◽  
Carlos Henrique Mesquita Peres ◽  
Alfredo Coimbra Reichl ◽  
Laila Patricia Fidelis Dutra

AbstractAtrial myxomas are the most common primary cardiac tumors and may manifest with neurological symptoms in ∼ 30% of cases. Cerebral ischemia, aneurysmal formation, and extravascular metastases are mechanisms that lead to these neurological manifestations. Perilesional changes on computed tomography (CT) and magnetic resonance imaging (MRI) may help in the diagnosis of myxomatous aneurysms, which are usually located in the distal middle cerebral artery (MCA) and in the posterior cerebral artery (PCA) circulation territories. Careful resection of the cardiac lesion is essential for preventing embolism. However, treatment of myxomatous aneurysms is controversial due to the limited understanding of the natural history of this condition. Treatment may include clinical observation in asymptomatic patients, surgical resection, endovascular approaches, adjuvant chemotherapy, and low-dose radiation therapy. We present one case of a female patient with myxomatous aneurysm secondary to an atrial myxoma who presented with neurological symptoms and another case of a female patient who developed neurological symptoms after initial surgical treatment of the primary lesion. Lesion growth rate, topography, morphology, and the patient's clinical condition must be considered when choosing a therapeutical method. Further clinical studies are needed to achieve a better understanding and treatment of this disease.


Genes ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1981
Author(s):  
Rachael C. Heath Jeffery ◽  
Jennifer A. Thompson ◽  
Johnny Lo ◽  
Tina M. Lamey ◽  
Terri L. McLaren ◽  
...  

Reported growth rates (GR) of atrophic lesions in Stargardt disease (STGD1) vary widely. In the present study, we report the longitudinal natural history of patients with confirmed biallelic ABCA4 mutations from five genotype groups: c.6079C>T, c.[2588G>C;5603A>T], c.3113C>T, c.5882G>A and c.5603A>T. Fundus autofluorescence (AF) 30° × 30° images were manually segmented for boundaries of definitely decreased autofluorescence (DDAF). The primary outcome was the effective radius GR across five genotype groups. The age of DDAF formation in each eye was calculated using the x-intercept of the DDAF effective radius against age. Discordance between age at DDAF formation and symptom onset was compared. A total of 75 eyes from 39 STGD1 patients (17 male [44%]; mean ± SD age 45 ± 19 years; range 21–86) were recruited. Patients with c.3113C>T or c.6079C>T had a significantly faster effective radius GR at 0.17 mm/year (95% CI 0.12 to 0.22; p < 0.001 and 0.14 to 0.21; p < 0.001) respectively, as compared to those patients harbouring c.5882G>A at 0.06 mm/year (95% CI 0.03–0.09), respectively. Future clinical trial design should consider the effect of genotype on the effective radius GR and the timing of DDAF formation relative to symptom onset.


2021 ◽  
pp. 1-9
Author(s):  
Marie Luby ◽  
José G. Merino ◽  
Rachel Davis ◽  
Saeed Ansari ◽  
Marc Fisher ◽  
...  

<b><i>Introduction:</i></b> Despite complete recanalization by mechanical thrombectomy, abnormal perfusion can be detected on MRI obtained post-endovascular therapy (EVT). The presence of residual perfusion abnormalities post-EVT may be associated with blood-brain barrier breakdown in response to mechanical disruption of the endothelium from multiple-pass thrombectomy. We hypothesize that multiple-pass versus single-pass thrombectomy is associated with a higher rate of residual hypoperfusion and increased lesion growth at 24 h. <b><i>Materials and Methods:</i></b> For this analysis, we included patients presenting to one of two stroke centers between January 2015 and February 2018 with an acute ischemic stroke within 12 h from symptom onset if they had a large vessel occlusion of the anterior circulation documented on magnetic resonance angiography or CTA, baseline MRI pre-EVT with imaging evidence of hypoperfusion, underwent EVT, and had a post-EVT MRI with qualitatively interpretable perfusion-weighted imaging data at 24 h. MRI <i>T</i><sub>max</sub> maps using a time delay threshold of &#x3e;6 s were used to quantitate hypoperfusion volumes. Residual hypoperfusion at 24 h was solely defined as <i>T</i><sub>max</sub> volume &#x3e;10 mL with &#x3e;6 s delay. Complete recanalization was defined as modified treatment in cerebral infarction visualized on angiography at EVT completion. Hyperintense acute reperfusion injury marker was assessed on post-EVT pre-contrast fluid-attenuated inversion recovery at 24 h. Major early neurological improvement was defined as a reduction of the admission National Institutes of Health Stroke Scale by ≥8 points or a score of 0–1 at 24 h. Good functional outcome was defined as 0–2 on the modified Rankin Scale on day 30 or 90. <b><i>Results:</i></b> Fifty-five patients were included with median age 67 years, 58% female, 45% Black/African American, 36% White/Caucasian, median admission National Institutes of Health Stroke Scale 19, large vessel occlusion locations: 71% M1, 14.5% iICA, 14.5% M2, 69% treated with intravenous recombinant tissue plasminogen activator. Of these, 58% had multiple-pass thrombectomy, 39% had residual perfusion abnormalities at 24 h, and 64% had severe hyperintense acute reperfusion injury marker at 24 h. After adjusting for complete recanalization, only multiple-pass thrombectomy (odds ratio, 4.3 95% CI, 1.07–17.2; <i>p</i> = 0.04) was an independent predictor of residual hypoperfusion at 24 h. Patients with residual hypoperfusion had larger lesion growth on diffusion-weighted imaging (59 mL vs. 8 mL, <i>p</i> &#x3c; 0.001), lower rate of major early neurological improvement (24% vs. 70%, <i>p</i> = 0.002) at 24 h, and worse long-term outcome based on the modified Rankin Scale at 30 or 90 days, 5 versus 2 (<i>p</i> &#x3c; 0.001). <b><i>Conclusions:</i></b> Our findings suggest that incomplete reperfusion on post-EVT MRI is present even in some patients with successful recanalization at the time of EVT and is associated with multiple-pass thrombectomy, lesion growth, and worse outcome. Future studies are needed to investigate whether patients with residual hypoperfusion may benefit from immediate adjunctive therapy to limit lesion growth and improve clinical outcome.


Stroke ◽  
2021 ◽  
Author(s):  
Theodore E. Liston ◽  
Aldric Hama ◽  
Johannes Boltze ◽  
Russell B. Poe ◽  
Takahiro Natsume ◽  
...  

Background and Purpose: Treatment with A1R/A3R (adenosine A1 and A3 receptor) agonists in rodent models of acute ischemic stroke results in significantly reduced lesion volume, indicating activation of adenosine A1R or A3R is cerebroprotective. However, dosing and timing required for cerebroprotection has yet to be established, and whether adenosine A1R/A3R activation will lead to cerebroprotection in a gyrencephalic species has yet to be determined. Methods: The current study used clinical study intervention timelines in a nonhuman primate model of transient, 4-hour middle cerebral artery occlusion to investigate a potential cerebroprotective effect of the dual adenosine A1R/A3R agonist AST-004. Bolus and then 22 hours intravenous infusion of AST-004 was initiated 2 hours after transient middle cerebral artery occlusion. Primary outcome measures included lesion volume, lesion growth kinetics, penumbra volume as well as initial pharmacokinetic-pharmacodynamic relationships measured up to 5 days after transient middle cerebral artery occlusion. Secondary outcome measures included physiological parameters and neurological function. Results: Administration of AST-004 resulted in rapid and statistically significant decreases in lesion growth rate and total lesion volume. In addition, penumbra volume decline over time was significantly less under AST-004 treatment compared with vehicle treatment. These changes correlated with unbound AST-004 concentrations in the plasma and cerebrospinal fluid as well as estimated brain A1R and A3R occupancy. No relevant changes in physiological parameters were observed during AST-004 treatment. Conclusions: These findings suggest that administration of AST-004 and combined A1R/A3R agonism in the brain are efficacious pharmacological interventions in acute ischemic stroke and warrant further clinical evaluation.


2021 ◽  
Author(s):  
Rosalie V. McDonough ◽  
Sarah Elsayed ◽  
Lukas Meyer ◽  
Theresa Ewers ◽  
Matthias Bechstein ◽  
...  

Abstract Background Computed-tomography perfusion (CTP) is frequently used to screen acute ischemic stroke (AIS) patients for endovascular treatment (EVT), despite known problems with ischemic “core” overestimation. This potentially leads to the unfair exclusion of patients from EVT. We propose that net water uptake (NWU) can be used in addition to CTP to more accurately assess the extent and/or stage of tissue infarction. Methods Patients treated for AIS between 06/2015-07/2020 were retrospectively analyzed. Baseline CTP-derived core volume (pCore) and NWU were determined. Logistic regression tested the relationship between baseline clinical and imaging variables and core-overestimation (primary outcome). The secondary outcomes comprised 90-day functional independence (modified Rankin score) and lesion growth. Results 284 patients were included. Median NWU was 7.2% (IQR:2.6–12.8). ASPECTS (RR:1.28,95%CI:1.09-1.51), NWU (RR:0.94,95%CI:0.89-0.98), onset to recanalization (RR:1.00,95%CI:0.99-1.00) and imaging (RR:1.00,95%CI1.00-1.00) times, and pCore (RR:1.02,95%CI:1.01-1.02) were significantly associated with core overestimation. Core-overestimation was more likely to occur in patients with large pCores and low NWU at baseline. NWU was significantly correlated with lesion growth. Conclusion NWU can be used as a supplemental tool to CTP during admission imaging to more accurately assess the extent of ischemia, particularly relevant for patients with large CTP-defined cores who would otherwise be excluded from treatment.


2021 ◽  
Vol 4 (12) ◽  
pp. e202101224
Author(s):  
Sangappa B Chadchan ◽  
Pooja Popli ◽  
Chandrasekhar R Ambati ◽  
Eric Tycksen ◽  
Sang Jun Han ◽  
...  

Worldwide, ∼196 million are afflicted with endometriosis, a painful disease in which endometrial tissue implants and proliferates on abdominal peritoneal surfaces. Theories on the origin of endometriosis remained inconclusive. Whereas up to 90% of women experience retrograde menstruation, only 10% develop endometriosis, suggesting that factors that alter peritoneal environment might contribute to endometriosis. Herein, we report that whereas some gut bacteria promote endometriosis, others protect against endometriosis by fermenting fiber to produce short-chain fatty acids. Specifically, we found that altered gut microbiota drives endometriotic lesion growth and feces from mice with endometriosis contained less of short-chain fatty acid and n-butyrate than feces from mice without endometriosis. Treatment with n-butyrate reduced growth of both mouse endometriotic lesions and human endometriotic lesions in a pre-clinical mouse model. Mechanistic studies revealed that n-butyrate inhibited human endometriotic cell survival and lesion growth through G-protein–coupled receptors, histone deacetylases, and a GTPase activating protein, RAP1GAP. Our findings will enable future studies aimed at developing diagnostic tests, gut bacteria metabolites and treatment strategies, dietary supplements, n-butyrate analogs, or probiotics for endometriosis.


2021 ◽  
Author(s):  
Bruce Campbell ◽  
Patricia Bourassa ◽  
Robert Aiello

The theory that lesions formed by retention of circulating LDL can then progress to complicated atherosclerotic lesions has been a subject of debate, as has the mechanism of retention. In earlier work, we identified SAMD1, a protein expressed by intimal smooth muscle cells in human lesions that appears to irreversibly bind apoB-Lps in extracellular matrix near the lumen. We hypothesized this binding could contribute to the formation of lesions in mice, and that inhibiting binding could reduce lesion growth. In mouse models of atherosclerosis, we found that SAMD1 binds LDL; that SAMD1/apoB complex is ingested by intimal cells; and that recognizable epitopes of the SAMD1/apoB complex survive some degree of catabolism in foam cell. These data appear to support the SAMD1/LDL retention hypothesis of lesion growth. Despite apparently irreversible binding of human LDL to full-length human SAMD1, efficient anti-SAMD1-antibody inhibitors were created. In vivo lesion targeting of inhibitors was demonstrated by MRI, ultrasound, and ex vivo microscopy. However, only non-statistically significant reductions in spontaneous lesion size in apoE-/- mice were seen after 12 weeks of treatment with PEG-fab inhibitors of SAMD1/LDL binding. In contrast, inhibitors substantially reduced LDL retention in carotid injury lesions in apoE-/- and LDLR-/- mice 7 days after injury. The most obvious difference between injury lesions and early spontaneous lesions is the presence of numerous SMCs and associated ECM in the injury lesions. Thus, SAMD1 may be involved in retention of apoB-Lps in mouse lesions, but not until smooth muscle cells have entered the intima. In addition, SAMD1 is seen throughout arteries in changing patterns that suggest broader and more complicated roles in atherosclerosis.


Author(s):  
E.J. Mallack ◽  
G. Askin ◽  
S. van de Stadt ◽  
P.A. Caruso ◽  
P.L. Musolino ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Ting Zhao ◽  
Hongyan Zhao

Objective. We applied computed tomography (CT) to explore the imaging manifestations of rare parts of osteochondroma. Based on the medical images, deblurring using a convolutional neural network (CNN), and three-dimensional (3D) reconstruction of the images is performed in order to improve the image diagnosis. Methods. Twelve cases of osteochondroma in rare locations confirmed by surgical pathology or clinical long-term dynamic observation were retrospectively analyzed using medical imaging and image reconstruction. There are 7 males and 5 females, with an average age of 43 years. CT examinations were performed in all cases. Image deblurring via the GAN model is performed followed by the 3D reconstruction of the higher quality images is implemented. A retrospective study was performed on the imaging manifestations of the above cases; the imaging characteristics were summarized. Results. The imaging features are the following lesions, including 4 cases of the proximal radius, 4 cases of the scapula, 2 cases of the pelvis, and 2 cases of the proximal ribs. The cartilage caps, cortex, and sternum were typical structures of the bone surface of the studied cases. In the continuous imaging features, calcification was visible in some cases, and no significant enhancement was seen in enhanced scans; there was no obvious direction of lesion growth. The image processing techniques that we performed are useful in enhancing the quality of the medical diagnosis. Conclusions. Rare site osteochondroma has certain imaging features. In most cases, we can accurately diagnose rare site osteochondroma through these features via the image processing methods that are proposed in this paper.


2021 ◽  
pp. 135245852110334
Author(s):  
Samuel Klistorner ◽  
Michael H Barnett ◽  
Con Yiannikas ◽  
Joshua Barton ◽  
John Parratt ◽  
...  

Background: Expansion of chronic multiple sclerosis (MS) lesion is associated with slow-burning inflammation at lesion rim. However, the underlying mechanisms leading to expansion are not fully understood. Objective: To investigate the relationship between diffusivity markers of demyelination and axonal loss in perilesional white matter and lesion expansion in relapsing-remitting MS (RRMS). Methods: T1, FLAIR and diffusion tensor images were acquired from 30 patients. Novel single-streamline technique was used to estimate diffusivity in lesions, perilesional white matter and normal-appearing white matter (NAWM). Results: Significant association was found between baseline periplaque radial diffusivity (RD) and subsequent lesion expansion. Conversely, periplaque axial diffusivity (AD) did not correlate with lesion growth. Baseline RD (but not AD) in periplaque white matter of expanding lesions was significantly higher compared with non-expanding lesions. Correlation between increase of both RD and AD in the periplaque area during follow-up period and lesion expansion was noticeably stronger for RD. Increase of RD in periplaque area was also much higher compared to AD. There was significant increase of AD and RD in the periplaque area of expanding, but not in non-expanding, lesions. Conclusion: Periplaque demyelination is likely to be an initial step in a process of lesion expansion and, as such, potentially represents a suitable target for remyelinating therapies.


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