Vascular Territories Research Articles

Carotid Artery Geometry Modifications and Clinical Implications after Carotid Artery Stenting

Background: Carotid artery stenting (CAS) could lead to a modification of the carotid bifurcation geometry with possible clinical implications. This study aimed to clarify the geometrical impact of three carotid stents with different designs on the carotid bifurcation and its clinical consequences. Methods: This was a retrospective single-center study. We included all patients who underwent CAS in a 3-year period. Anatomical changes of the carotid bifurcation were evaluated by reviewing angiographic images. The population was divided into three groups based on the stent implanted: Group 1 (Carotid Wallstent), Group 2 (Roadsaver), and Group 3 (C-Guard). Results: A total of 226 patients were included. The mean age was 77.0 ± 7.4 years and 72.5% (164/226) were male. Three different stents were implanted into three groups: Group 1 (n = 131/226, 58%), Group 2 (n = 57/226, 25.2%), and Group 3 (n = 38/226, 16.8%). The mean pre-stent implantation CCA-ICA angle of the entire population was 155 ± 14.9°, and the post-CAS angle was 167.7 ± 8.7° (p = 0.0001). In every subgroup, the difference was statistically different, with the biggest difference registered in Group 2 (−16.1 ± 13.2°). Regarding stent oversizing, there was a significant relationship between CCA oversizing and CCA-ICA angle modification (p = 0.006). During follow-up, a total of 14 (6.2%) restenoses were registered. The mean CCA-ICA angle modification in the restenosis group was −9.5 ± 14.4° vs. −12.8 ± 11.9° in the no-restenosis group with no significant statistical differences were outlined (p = 0.3). Conclusions: Compared to the Carotid Wallstent and C-Guard, the Roadsaver stent appears to have a lower adaptability to the carotid vascular territory, resulting in a higher CCA-ICA angle modification after implantation, with no impact on the stent restenosis rate.

Association between silent cerebral embolism and cognitive alterations following transcatheter aortic valve replacement in bicuspid versus tricuspid aortic valve patients

Abstract Background Silent cerebral ischemic lesions (SCILs) is a common magnetic resonance imaging (MRI) finding in severe aortic stenosis patients post - transcatheter aortic valve replacement (TAVR). We evaluated the association between SCILs and cognitive alterations in patients with bicuspid aortic valve (BAV) versus tricuspid aortic valve (TAV) post-TAVR. Methods This study enrolled 100 consecutive TAVR (45 with BAV and 55 TAV). DW-MRI and neurocognitive evaluation (MoCA score) were performed at baseline, discharge, and 1- and 12-month post-discharge. Results Ninety-two out of the 100 patients (92%) exhibited cognitive dysfunction at baseline. Post-TAVR, overall cognitive function significantly improved, the average MOCA score increased from 18.69±6.74 to 22.18±6.30. During the 1-year follow-up, 54 patients demonstrated improved cognitive function, and the number of patients with moderate-to-severe cognitive dysfunction (MoCA score < 18) significantly decreased from 32 to 16. Prevalence of SCILs was 14% and 72% at baseline and discharge, respectively. New SCILs were observed in 60 patients at discharge, distributed across all vascular territories, averaging 4 lesions with a total volume of 215.4±195.4mm3. Although no significant correlation existed between total volume of new SCILs and cognitive changes post-TAVR (R=-0.133, p=0.206), patients with SCILs still displayed significant cognitive improvement (MoCA score from 18.4±6.6 to 22.0±7.1), whereas patients who developed large SCILs (lesion diameter >9) showed less improvement compared to those with small or median SCILs (number of patients who had cognitive improvement: 32 vs. 52, p<0.05). Cognitive function improvement post-TAVR did not significantly differ between BAV and TAV patients, MoCA scores were comparable (BAV group, n=45, from 18.63±6.68 to 21.88±6.80 vs. TAV group, n=55, from 18.73±6.81 to 22.42±5.80; p>0.05). DW-MRI revealed more new SCILs in BAV patients post-TAVR compare to TAV patients (235 lesions vs. 150 lesions, respectively). In BAV patients, SCILs primarily manifested in small and medium sizes (224 lesions), despite more severe calcification (valvular calcium volume 956.5±644.0 mm vs. 634.4±508.0 mm3; p=0.028). The number of large lesions was similar in the two groups (11 in BAV group and 10 in TAV group). Conclusion TAVR demonstrates positive effects on improving cognitive function in aortic stenosis patients, despite common occurrence of SCILs in both BAV and TAV patients. Cognitive function post-TAVR was comparable between BAV and TAV patients. The cognitive improvement from TAVR may be less impacted by small- and medium-sized SCILs, while severe SCILs might impede or diminish the cognitive benefits of TAVR.table

DWI lesions after intracranial aneurysm treatment with contour or WEB-does the device matter?

In this study, we report our experience with the occurrence of diffusion-weighted imaging (DWI) lesions following aneurysm treatment with Woven EndoBridge (WEB) device and Contour Neurovascular System in elective settings. We compared both techniques in a retrospective single-center analysis, to investigate whether there are significant differences in the incidence of microemboli depending on the device used. Sixty-two cases treated with Contour were retrospectively compared with 84 WEB cases. Postinterventional MRI was performed in all patients within five days after the angiographic procedure. Only DWI lesions in the dependent vascular territory of the treated aneurysm were considered. Data on occurrence of DWI lesions, device implantation times as well as device change or repositions maneuvers were compared. A total of 146 patients were included in this study. Postinterventional DWI lesions were detected in 33 of the 62 (53.2%) Contour cases and in 36 of the 84 (42.8%) WEB cases with an average lesion number of 1.70 ± 3.45 in our WEB group and 1.68 ± 2.53 in our Contour cohort. Neither periinterventional device changes nor device reposition maneuvers had a significant impact on the occurrence of DWI lesions. Although four patients experienced transient neurological deterioration, the DWI lesions were not clinically relevant at the time of discharge, as the patients' NIHSS remained stable compared to the preintervention NIHSS in the entire cohort. There was no statistically significant difference between the implantation times of WEB and Contour, although Contour could be implanted slightly faster. Aneurysm treatment with WEB or Contour results in a comparable numbers of procedure-related DWI lesions. This effect was consistent after adjustment for other demographic or technical variables.

Computed tomography for the detection of myocardial hypoperfusion in acute myocardial infarction and the associated CT-to-catheter time

Emergency computed tomography (CT) often does not allow for comprehensive coronary artery assessment. However, CT may reveal pathological myocardial hypoperfusion suggestive of acute myocardial infarction (AMI), especially in patients presenting with a different diagnostic hypothesis. CT hypoperfusion is known to be associated with myocardial infarction, however the diagnostic value of CT hypoperfusion for the detection of AMI is still not well evaluated. This was a single-centre retrospective study including patients who underwent invasive coronary angiography (ICA) due to suspected AMI based on incidental perfusion defects upon emergency CT imaging between 2018 and 2023. A total of 22 patients (mean age 66.3 ± 10.8 years, 11 female) were included in this analysis. The diagnosis of AMI was established in all cases leading to ICA. Culprit coronary artery lesions with an indication of percutaneous coronary intervention were detected in all patients who underwent ICA. Spearmann correlation for hypoperfused segments on CT imaging and the corresponding vascular territory upon ICA was significantly substantial (ρ = 0.73, p = < 0.001). The higher the number of affected myocardial segments, the faster ICA was initiated. Mean time between the suspicion of AMI on CT imaging and ICA was 196 (29–4044) minutes. Myocardial hypoperfusion on emergency CT imaging should be considered as AMI until proven otherwise, independent of the clinical scenario leading to performance of CT imaging and whether imaging was performed for the exclusion of non-cardiac pathologies. Early initiation of further diagnostic workup may potentially avoid delays to invasive treatment and reduce the CT-to-catheter-time. Our study explicitly underlines that myocardial hypoperfusion upon contrast enhanced CT imaging needs to be considered as sign of acute myocardial infarction and indicates targeted clinical workup to rule out this diagnosis and to shorten the timeframe from imaging diagnosis to interventional treatment.

Retinal and cerebral hemodynamics redistribute to favor thermoregulation in response to passive environmental heating and heated exercise in humans

ABSTRACT Core temperature (TC) changes, alongside exercise, affect hemodynamic responses across different conduit and microvascular beds. This study investigated impacts of ecologically valid environmental heat and exercise exposures on cerebral, skin and retinal vascular responses by combining physiological assessments alongside computational fluid dynamics (CFD) modeling. Young, healthy participants (n = 12) were exposed to environmental passive heating (PH), and heated exercise (HE) (ergometer cycling), in climate-controlled conditions (50 mins, 40°C, 50% relative humidity) while maintaining upright posture. Blood flow responses in the common carotid (CCA), internal carotid (ICA) and central retinal (CRA) arteries were assessed using Duplex ultrasound, while forearm skin microvascular blood flow responses were measured using optical coherence tomography angiography. Three-dimensional retinal hemodynamics (flow and pressure) were calculated via CFD simulation, enabling assessment of wall shear stress (WSS). TC rose following PH (+0.2°C, p = 0.004) and HE (+1.4°C, p < 0.001). PH increased skin microvascular blood flow (p < 0.001), whereas microvascular CRA flow decreased (p = 0.038), despite unchanged ICA flow. HE exacerbated these differences, with increased CCA flow (p = 0.007), unchanging ICA flow and decreased CRA flow (p < 0.001), and interactions between vascular (CCA vs. ICA p = 0.018; CCA vs. CRA p = 0.004) and microvascular (skin vs. retinal arteriolar p < 0.001) territories. Simulations revealed patterns of WSS and lumen pressure that uniformly decreased following HE. Under ecologically valid thermal challenge, different responses occur in distinct conduit and microvascular territories, with blood flow distribution favoring systemic thermoregulation, while flow may redistribute within the brain.

Evaluation of incidence and outcomes of compressive extradural haematoma-related infarcts in the paediatric population.

Traumatic extradural haematoma (EDH) is one of the neurosurgical emergencies in the paediatric population. One of the rare complications of extradural haematoma is adjacent parenchymal infarct from the compressive effect of haematoma leading to further morbidity. We aimed to evaluate the incidence and outcomes of this rare complication in paediatric trauma patients. We undertook a retrospective review of all operative extradural haematoma cases in single centre paediatric neurosurgical unit between the years 2008 and 2024. Cases with postoperative imaging were analysed for demographics, age, sex, dimensions of haematoma and underlying infarct, pre-operative GCS and pupillary abnormality and time interval from scan to surgery. Infarct was defined as well-defined parenchymal hypodensity corresponding to vascular territory and not attributable to contusions on postoperative CT head performed at 24-72 h. All patients suspected of stroke had further MRI brain for evaluation. Statistical analysis was then performed comparing groups with and without infarct. Overall, 115 cases of extradural haematoma were identified during the study period. Eighty cases had adequate postoperative imaging to allow assessment for infarcts; 7.5% demonstrated evidence of infarct underlying extradural haematoma. Mean age in the infarct group was 1.8 years (M:F ratio 2:1) with mean EDH dimensions of 77 mm × 31.4 mm × 79.7 mm). Mean age in the non-infarct group was 8.6 years (M:F ratio 2:1) with mean EDH dimensions of (57.5 mm × 19.6 mm × 62.6 mm). Children with infarcts were significantly younger with larger haematoma dimensions and hada higher proportion of pupillary abnormalities. There was no significant difference in pre-operative GCS and scan-to-surgery time-lapse between the groups with and without infarct. Compressive effect of EDH can lead to underlying parenchymal infarct. Children with extradural haematoma-related infarct were younger with larger haematoma size and a higher proportion of pupillary abnormalities.

Stent-Induced Inflammation: A Comparative Cross-Sectional Study of Post-Implantation Syndrome in Venous and Arterial Procedures

Background: Postimplantation syndrome (PIS) is a known inflammatory response following endovascular stent placement, yet comparative data between venous and arterial stenting remains limited. This study seeks to evaluate the incidence, characteristics, and clinical implications of PIS across these two distinct vascular territories. Methods: We retrospectively analyzed 191 patients who underwent either venous (n = 36) or arterial (n = 155) stent placement. Data collection encompassed demographic profiles, perioperative laboratory findings, and clinical outcomes. The primary endpoint was the incidence of PIS, defined as the presence of fever (≥38 °C), leukocytosis, and elevated C-reactive protein (CRP) within 30 days postprocedure. Secondary outcomes included length of hospital and ICU stay, incidence of endoleaks, reintervention rates, and 30-day mortality. Comparative statistical analyses were conducted to assess differences between the venous and arterial stent groups. Results: PIS was observed more frequently in arterial stent patients, as evidenced by significantly elevated postoperative white blood cell counts at 24 and 48 h (p = 0.046 and p = 0.014, respectively), along with borderline CRP increases (p = 0.052). Fever occurrence peaked at 72 and 96 h postprocedure, predominantly in the arterial cohort. Furthermore, patients with arterial stents had significantly longer hospital stays (5.59 ± 0.46 days vs. 3.42 ± 0.36 days; p = 0.0018) and a higher rate of 30-day endoleaks (7.1% vs. 0%; p = 0.005). Despite similar mortality and major adverse cardiac event (MACE) rates between groups, arterial stent patients exhibited a greater need for reintervention. While PIS was less common among venous stent recipients, its potential impact on postoperative recovery warrants careful monitoring. Conclusions: Arterial stenting is associated with a higher incidence of PIS and a more pronounced systemic inflammatory response, contributing to longer hospitalization and increased postoperative complications. Although venous stent patients experience PIS less frequently, its occurrence should not be overlooked, as it may influence overall recovery and clinical outcomes. Recognition and management of PIS in both venous and arterial stent patients are critical to improving patient care and optimizing procedural success.

Macrovascular blood flow and microvascular cerebrovascular reactivity are regionally coupled in adolescence.

Cerebrovascular imaging assessments are particularly challenging in adolescent cohorts, where not all modalities are appropriate, and rapid brain maturation alters hemodynamics at both macro- and microvascular scales. In a preliminary sample of healthy adolescents (n=12, 8-25 years), we investigated relationships between 4D flow MRI-derived blood velocity and blood flow in bilateral anterior, middle, and posterior cerebral arteries and BOLD cerebrovascular reactivity in associated vascular territories. As hypothesized, higher velocities in large arteries are associated with an earlier response to a vasodilatory stimulus (cerebrovascular reactivity delay) in the downstream territory. Higher blood flow through these arteries is associated with a larger BOLD response to a vasodilatory stimulus (cerebrovascular reactivity amplitude) in the associated territory. These trends are consistent in a case study of adult moyamoya disease. In our small adolescent cohort, macrovascular-microvascular relationships for velocity/delay and flow/CVR change with age, though underlying mechanisms are unclear. Our work emphasizes the need to better characterize this key stage of human brain development, when cerebrovascular hemodynamics are changing, and standard imaging methods offer limited insight into these processes. We provide important normative data for future comparisons in pathology, where combining macro- and microvascular assessments may better help us prevent, stratify, and treat cerebrovascular disease.

Absence of the Susceptibility Vessel Sign with Cancer-Associated Hypercoagulability-Related Stroke.

The susceptibility vessel sign, a hypointense signal on MR T2-weighted gradient-recalled echo images, is associated with erythrocyte-predominant thrombi, which are often present in cardioembolism. In contrast, cancer-associated hypercoagulability (CAH)-related stroke, which is presumably caused by fibrin-predominant thrombi, is associated with the absence of the susceptibility vessel sign. We hypothesized that the prevalence of the susceptibility vessel sign may be helpful in distinguishing CAH-related stroke from cardioembolism. This study attempted to validate this hypothesis and investigated the usefulness of the susceptibility vessel sign in differentiating CAH-related stroke from cardioembolism. We retrospectively studied patients with both CAH-related stroke (CAH group) and cardioembolism (cardioembolism group) who had major cerebral artery occlusion on MRA that was performed within 6 hours of stroke onset. All patients visited our department from 2015 to 2021. CAH-related stroke was defined as the following: 1) complication of active cancer, 2) pretreatment D-dimer value of >3 μg/mL, 3) multiple vascular territory infarctions, and 4) lack of any other specifically identified causes of stroke. We compared susceptibility vessel sign positivity rates within each group. Multivariable logistic regression analysis was used to assess the association between the absence of the susceptibility vessel sign and CAH-related stroke. Of 691 patients with CAH-related stroke or cardioembolism, major cerebral artery occlusion was observed in 10 patients in the CAH group and 198 patients in the cardioembolism group. The absence of the susceptibility vessel sign was identified in 55 of 208 patients and was significantly more frequent in the CAH group versus the cardioembolism group (90% versus 24%, P < .05). For predicting CAH-related stroke, the absence of the susceptibility vessel sign demonstrated a sensitivity of 90% (95% CI, 59%-99%), specificity of 78% (95% CI, 71%-83%), a positive predictive value of 18% (95% CI, 10-31), a negative predictive value of 99% (95% CI, 96%-99%), and a likelihood ratio of 4.06. Multivariable logistic regression analysis revealed that the absence of the susceptibility vessel sign was independently associated with CAH-related stroke (OR, 43; 95% CI, 6.8-863; P < .01). The absence of the susceptibility vessel sign was more frequent in CAH-related stroke than in cardioembolism. These findings could potentially be helpful for clinical management and differentiating cardioembolism and CAH-related stroke.

Physiological provocation compared to acetazolamide in the assessment of cerebral hemodynamics: a case report

BackgroundSevere large vessel disease may lead to cerebral hemodynamic failure that critically impairs cerebral blood flow (CBF) regulation elevating the risk of ischemic events. Assessment of the condition is often based on changes in CBF during vasodilatation; however, pharmacologically induced vasodilation does not reflect the physiological condition during an ischemic event caused by hemodynamic failure. We compared a [15O]H2O PET brain scan during vasodilation to a [99mTc]HMPAO SPECT brain scan during an ongoing transient ischemic attack (TIA).Case presentationA single patient presenting with limb-shaking TIA underwent CT, Digital Subtraction Angiography, and two different modalities of cerebral perfusion scans: [15O]H2O PET and [99mTc]HMPAO SPECT. Acetazolamide was used in the PET scan to induce vasodilatation, and during the SPECT scan physiological stress, standing up rapidly, was used to induce limb-shaking TIA. CT-angiography and Digital Subtraction Angiography revealed an occlusion in the distal part of the right A2 segment of the anterior cerebral artery, with a corresponding infarction in the watershed area. Collaterals supplied the main vascular territory of the anterior cerebral artery. During rest, neither perfusion modalities demonstrated reduced perfusion outside of the ischemic core. However, we found a pronounced difference between the PET utilizing acetazolamide and the SPECT during the TIA. The PET scan demonstrated relative hypoperfusion in vascular territory supplied by collaterals, while the area around the ischemic core was not affected. Contrary, the SPECT had only minor relative hypoperfusion in the collateral-supplied area, whereas the watershed area proximal to the infarct core had pronounced relative hypoperfusion.ConclusionsThe observed discrepancy in compromised areas during physiological provocation compared to pharmacological induced vasodilation questions the use of an unphysiological stressor for assessment of cerebrovascular hemodynamics. A physiological provocation test may achieve more clinically relevant evaluation.

Zygomatic Anterolateral Temporal Approach for P1/P2 segment complex posterior cerebral aneurysm: a single-center retrospective study.

Treating complex posterior cerebral artery (PCA) aneurysms, such as fusiform, giant, and dissecting aneurysms, poses significant challenges. Parent artery occlusion carries a risk of ischemic stroke and fails to alleviate mass effects. This study aims to analyze the technical nuances and patient outcomes of treating complex PCA aneurysms, ranging from the P1 to P2P segments, using a Zygomatic Anterolateral Temporal Approach(ZATA) combined with flow reconstruction. This study was a retrospective study. Surgical treatment was performed on twelve patients with complex PCA aneurysms located in the P1 to P2P segments. Ten patients underwent flow reconstruction including Superficial Temporal Artery(STA)-Middle Cerebral Artery(MCA),Internal Maxillary Artery(IMA)-Radial Artery(RA)-MCA,STA-PCA(P2), and IMA-RA-PCA(P2). The aneurysm occlusion rate, surgical complications, and patient prognosis, including stroke occurrence/ modified Rankin Scale(mRS), were recorded and analyzed. Using the ZATA, all twelve complex PCA aneurysms were successfully clipped/resected/trapped. This included two high-position aneurysms (> 3mm above the posterior clinoid process) at the P1/P2 junction and three P2P aneurysms. The mass effects of six large or giant aneurysms were resolved or alleviated. Postoperative and follow-up CTA/DSA confirmed the patency of the bypass vessels. Four patients experienced strokes in the perioperative period, with three ischemic and one hemorrhagic. The median follow-up period was 28.5months. At the last follow-up, the good prognosis rate (mRS ≤ 2) was 83.3%, and one patient had died. Clipping/resection/trapping of aneurysms via the ZATA, combined with flow reconstruction, is a feasible option for treating complex PCA aneurysms from the P1 to P2P segments. This approach helps maintain or improve cerebral perfusion in the affected vascular territory.

Preventability of ischemic stroke/transient ischemic attack in a tertiary care center in Argentina

IntroductionCardiovascular disease remains a leading cause of morbidity and mortality worldwide, with many individuals presenting with acute ischemic stroke or transient ischemic attack (AIS/TIA) due to underlying vascular risk factors (VRF). While these patients typically undergo routine evaluations for acute treatment, the prevention of these conditions is often underestimated. This study reports the prevalence of non-optimized VRF and estimates their degree of avoidability in a cohort of patients treated in a tertiary care center following AIS/TIA. MethodsThis retrospective study enrolled patients older than 18 years who experienced AIS/TIA over a two-year period. Preventability was defined as the degree to which an acute cerebrovascular event could have been prevented if the VRF had been appropriately treated. Using the variables determined at the onset of AIS or TIA, we developed a 10-point scale to classify the degree of preventability (not preventable [score of 0], low preventability [score of 1–3], and high preventability [score of 4 or higher]). We further defined sub-scores based on the effectiveness of treatment of high blood pressure [HBP] (0-2 points), dyslipidemia [DLP] (0-2 points), atrial fibrillation [AF] (1 point), active smoking [AS] (1 point), obesity (1 point), previous coronary heart disease [CHD] (1 point), and previous AIS/TIA (2 points). Demographic factors, etiologies, and imaging findings were evaluated, tabulated independently, and subsequently correlated with clinical findings extracted from the available patient records. ResultsOf the 395 patients (334 with AIS and 61 with TIA), 376 (95.19 %) exhibited some degree of preventability, whereas 19 (4.81 %) presented with a nonpreventable event. In total, 296 (74.94 %) presented a low preventable event, and 80 (20.25 %) presented a high preventable event. Applying the Chi-square test of independence to stroke etiology highlighted cardio-aortic embolism and large artery atherosclerosis as groups with a significantly higher burden of risk factors necessitating intervention, while patients with stroke of other etiologies had more adequate control of VRF. In terms of stroke severity, as determined by the National Institutes of Health Stroke Scale (NIHSS), patients with NIHSS scores >5 were more likely to experience preventable events. According to the ABCD2 score, higher risk scores were significantly associated with a higher preventive factor burden; however, age, sex, vascular territory, and Canadian TIA scores were not related to the prevention of AIS/TIA. ConclusionsThe high percentage of preventable events reflects the need to study other factors that may contribute to unhealthy lifestyles in this population. Potential reasons for poor health include high levels of stress, sleep deprivation, working conditions and an unhealthy diet. Further studies are required to better understand these phenomena.

Magnetic resonance imaging features and stroke etiology of ischemic stroke in essential thrombocythemia

BackgroundVarious essential thrombocythemia (ET)-related stroke mechanisms have been proposed, including microcirculatory disturbance due to coagulopathy, vasculitis, and embolism due to thrombus formation in large vessels. However, the stroke mechanism in ET remains largely unexplored. The purpose of this study was to evaluate magnetic resonance image (MRI) features of ischemic stroke in ET and determine the potential stroke mechanism. MethodsWe retrospectively collected data from 21 acute ischemic stroke patients with ET who were admitted to two stroke centers between 2010 and 2023. ET was diagnosed according to the World Health Organization criteria. We evaluated MRI features including the diffusion-weighted image (DWI) lesion pattern, and the presence of hemorrhagic transformation and intracranial artery steno-occlusive lesion, as well as other etiological workup results. ResultsOf 21 patients, 20 exhibited multiple ischemic lesions on DWI, mainly within a single vascular territory. Cortical infarcts were observed in 19 patients. Hemorrhagic transformation occurred in 15 patients. Additionally, 15 patients had intracranial steno-occlusive arteries, which regressed to normal in 11 patients during follow-up. Out of all patients, only 2 had potential causes of stroke other than ET (1 with atrial fibrillation and 1 with intracranial atherosclerotic stenosis). The remaining 19 patients had ET as the only identified potential cause. ConclusionsMRI features, including DWI lesion pattern in ischemic stroke patients with ET, suggested embolic etiology despite the absence of major embolic sources. Intra-arterial thrombus appears to be part of the stroke mechanism related to ET and may contribute to ischemic stroke in ET.

Giant Cell Arteritis and Takayasu Arteritis: Are They Similar or Different?

Vasculitis is a group of heterogeneous conditions characterised by inflammation of blood vessels. Based on the predominant size of the affected vessel, vasculitis is classified into small, medium, and large vessel vasculitis (LVV). Giant cell arteritis (GCA) and Takayasu’s arteritis (TAK) are the two major types of LVV. GCA was thought to affect only the external carotid artery and its branches, whereas, TAK was thought to affect the aorta and its major branches. Advances in imaging techniques have led to a better understanding of these conditions. It has become increasingly clear that GCA can involve the aorta and its branches. GCA and TAK have overlapping features like propensity to affect the aorta and its branches, similar histopathology, and similar clinical features. However, there are differences in age, geographic location, genetics, and predominant vascular territory involvement. There are subtle differences in clinical features. Are these conditions different ends of the same spectrum or different conditions with similar features? This review compares and contrasts these two conditions based on epidemiology, genetics, pathology, predominant vascular territory involvement, and any differential response to treatment. Based on current evidence, GCA and TAK seem to be distinct conditions and not different ends of the same spectrum.

Watershed regions are more susceptible to tissue microstructural injury in multiple sclerosis.

Histopathologic studies report higher concentrations of multiple sclerosis white matter lesions in watershed areas of the brain, suggesting that areas with relatively lower oxygen levels may be more vulnerable to disease. However, it is unknown at what point in the disease course lesion predilection for watershed territories begins. Accordingly, we studied a cohort of people with newly diagnosed disease and asked whether (1) white matter lesions disproportionally localize to watershed-regions and (2) the degree of microstructural injury in watershed-lesions is more severe. Fifty-four participants, i.e. 38 newly diagnosed people with multiple sclerosis, clinically isolated syndrome or radiologically isolated syndrome, and 16 age- and sex-matched healthy controls underwent brain magnetic resonance imaging. T1-weighted and T2-weighted fluid-attenuated inversion recovery sequences, selective inversion recovery quantitative magnetisation transfer images, and the multi-compartment diffusion imaging with the spherical mean technique were acquired. We computed the macromolecular-to-free pool size ratio, and the apparent axonal volume fraction maps to indirectly estimate myelin and axonal integrity, respectively. We produced a flow territory atlas in each subject's native T2-weighted fluid-attenuated inversion recovery images using a T1-weighted magnetic resonance imaging template in the Montreal Neurological Institute 152 space. Lesion location relative to the watershed, non-watershed and mixed brain vascular territories was annotated. The same process was performed on the T2-weighted fluid-attenuated inversion recovery images of the healthy controls using 294 regions of interest. Generalized linear mixed models for continuous outcomes were used to assess differences in size, pool size ratio and axonal volume fraction between lesions/regions of interests (in healthy controls) situated in different vascular territories. In patients, we assessed 758 T2-lesions and 356 chronic black holes (cBHs). The watershed-territories had higher relative and absolute concentrations of T2-lesions (P≤0.041) and cBHs (P≤0.036) compared to either non-watershed- or mixed-zones. T2-lesions in watershed-areas also had lower pool size ratio relative to T2-lesions in either non-watershed- or mixed-zones (P = 0.039). These results retained significance in the sub-cohort of people without vascular comorbidities and when accounting for periventricular lesions. In healthy controls, axonal volume fraction was higher only in mixed-areas regions of interest compared to non-watershed-ones (P = 0.008). No differences in pool size ratio were seen. We provide in vivo evidence that there is an association between arterial vascularisation of the brain and multiple sclerosis-induced tissue injury as early as the time of disease diagnosis. Our findings underline the importance of oxygen delivery and healthy arterial vascularisation to prevent lesion formation and foster a better outcome in multiple sclerosis.

From Angiosomal to Bi-Angiosomal and Extra-Angiosomal Pedicled Perforator Flaps: Optimizing the Use of Local Tissues in Abdominal Wall Reconstruction.

The use of free-style and propeller perforator-based flaps has been popularized for the reconstruction of moderate size defects in the trunk and extremities, while their application in the field of abdominal reconstruction is seldom reported. The purpose of this report is to describe the authors experience with the use of pedicled perforator-based flaps in abdominal wall reconstruction, presenting the innovative concept of transition from angiosomal to bi-angiosomal and extra-angiosomal perforator flaps and showing applications of the different flap designs according to the multiple clinical scenarios. A total of 15 patients underwent abdominal wall reconstruction with angiosomal, bi-angiosomal, and extra-angiosomal pedicled perforator-based flaps harvested from the surrounding abdominal subunits for superficial or full thickness defects of the abdominal wall of moderate and large dimensions. The defects were consequent to soft-tissue sarcomas (STS) and non-melanoma skin cancer (NMSC) resection in 11 and 4 cases, respectively. Operative data, post-operative course, and complications were recorded. Moreover, at 12 months follow-up, patients were asked to rate the esthetic and functional outcomes of the reconstructive procedure on a 5-point Likert scale. Ten angiosomal perforator flaps (4 DIEP, 4 SCIP, 1 SEAP, and 1 LICAP flaps) and 5 bi-angiosomal and extra-angiosomal conjoined perforator flaps including different vascular territories (3 bilateral DIEP, 1 bilateral SEAP, and 1 ipsilateral DIEP-SEAP flap) were successfully transferred in 15 patients. In two patients, microsurgical anastomoses were performed to guarantee proper vascularization of the additional cutaneous territory. Mean age was 59.3 years. Defect sizes ranged from 98 to 408 cm2 (mean size was 194.7 cm2). Mean operative time was 280 min. Flap surface ranged from 108 to 336 cm2 (mean surface was 209.3 cm2). No major complications were registered. One bi-angiosomal bilateral DIEP flap suffered from partial necrosis and required an additional flap reconstruction. All patients underwent a 12-month follow-up except one, who did not show for clinical follow-up but responded at the Likert scale at clinical follow-up at 9 months. Overall patients' satisfaction was high, with mean esthetic and functional ratings of 4.27 and 3.87. The use of local tissues is an under-utilized solution in the field of abdominal wall reconstruction. Angiosomal, bi-angiosomal, and extra-angiosomal perforator flaps proved to be a reliable option to provide the transfer of a significant amount of tissue and offer like with like reconstruction while maximizing flap survival.

Cutaneous Manifestations of Liver Disease: A Narrative Review.

Chronic liver disease is a major cause of morbidity and mortality. The most common extrahepatic manifestations are dermatological. The pathophysiology of these dermatological manifestations is not clear, but it is postulated that the mechanisms involved include generalized vasodilatation, hyperdynamic blood circulation, and altered estrogen metabolism. The most common cutaneous manifestations of liver disease are Terry's nails and pruritus. Terry's nails consist of leukonychia with a distal pink band and the absence of the lunula. The main differential diagnosis is Lindsay's nails. Vascular manifestations of liver disease include palmar erythema and arachnoid nevi, the latter located in the vascular territory of the superior vena cava and occurring in chronic alcohol-associated liver disease. Dermatological manifestations generally resolve with improvement or remission of liver disease, and there is no specific treatment for them. However, bile acid chelators are the first line of treatment for cholestatic pruritus. Studying dermatological manifestations of liver disease contributes to early diagnosis and treatment, potentially improving the patient's prognosis.

The Mcgregor Pedicled Groin Flap for Hand Skin Defects

The groin flap is a surgical method used to cover soft tissue defects in the hand and forearm, such as wounds, traumatic amputations, degloving injuries, burns, burn scar release, and tumor excision. It is effective in covering extensive and intricate defects, such as wounds, traumatic amputations, degloving injuries, burns, burn scar release, and tumor excision. The procedure involves a remote autoplasty supported by the vascular territory of the superficial iliac circumflex artery. The flap's boundaries are defined using the "2 fingers width" criterion, and the flap is raised from lateral to medial, transferring subcutaneous tissue while keeping it above the fascia. The flap is closed using drain suction, and the patient is allowed to walk on the 5th day after surgery. Effective preoperative planning is essential for preventing the creation of too big or too tiny flaps and ensuring the fabrication of appropriate tubing to avoid complications. The McGregor groin flap is a commonly used technique for hand deformity reconstruction due to its extended pedicle and quick execution. It is adaptable, repeatable, and can be performed by less-experienced surgeons without microsurgery expertise. The flap covers significant tissue loss with pliable tissue, making it suitable for joints. It can cover abnormalities on the back or palm, and can be used for early wrist and hand rehabilitation. However, it has drawbacks, such as shoulder stiffness in older patients, discomfort during the upper limb positioning, and the need for multiple phases. Despite these, the groin flap remains relevant in the age of microsurgery and can be improved with technical modifications.

7T-high resolution MRI-derived radiomic analysis for the identification of symptomatic intracranial atherosclerotic plaques.

High-resolution magnetic resonance imaging (HR-MRI) allows for detailed visualization of intracranial atherosclerotic plaques. Radiomics can be used as a tool for objective quantification of the plaque's characteristics. We analyzed the radiomics features (RFs) obtained from 7 T HR-MRI of patients with intracranial atherosclerotic disease (ICAD) to determine distinct characteristics of culprit and non-culprit plaques. Patients with stroke due to ICAD underwent HR-MRI. Culprit plaques in the vascular territory of the stroke were identified. Degree of stenosis, area degree of stenosis and plaque burden were calculated. A three-dimensional segmentation of the plaque was performed, and RFs were obtained. A machine learning model for prediction and identification of culprit plaques using significantly different RFs was evaluated. The study included 33 patients with ICAD as stroke etiology. Univariate analysis revealed 24 RFs in pre-contrast MRI, 21 in post-contrast MRI, 13 RFs that were different between pre and post contrast MRIs. Additionally, six shape-based RFs significantly differed from culprit and non-culprit plaques. The random forest model achieved an accuracy rate of 81% (88% sensitivity and 75% specificity) in identifying culprit plaques in the independent testing dataset. This model successfully identified the culprit plaques in all patients during the testing phase. Symptomatic plaques had a distinct signature RFs compared to other plaques within the same subject. A machine learning model built with RFs successfully identified the symptomatic atherosclerotic plaques in most cases. Radiomics is a promising tool for stratification of plaques in patients with ICAD.

Atherosclerosis Prevalence among Different Physical Activity Patterns in Adult Men.

Background: Physical activity (PA) intensity could play a key role in atherosclerosis risk, but the existing literature shows controversial results. The aim of this study was to analyze the association of different PA levels with the presence of subclinical atherosclerosis in femoral and carotid arteries. Methods: A cross-sectional analysis was conducted of 449 middle-aged men belonging to the Aragon Workers' Health Study. Demographic, anthropometric, and clinical data were obtained during the annual medical examination. Ultrasonography was used to assess the presence of atheroma plaques in femoral and carotid territories. Accelerometry was used to assess habitual PA. Participants were categorized into vigorous PA (VPA) groups (0 min/week, >0-60 min/week, >60 min/week), and into moderate to vigorous PA (MVPA) groups using terciles as cut-offs. Results: Compared with participants who completed 0 min/week of VPA, those participants who completed >60 min/week of VPA had fully adjusted odds of subclinical atherosclerosis of 0.47 (95%CI: 0.22, 0.99, p < 0.05) and 0.35 (95%CI: 0.17, 0.73, p < 0.05) for femoral and any territory (femoral and/or carotid) respectively. No significant differences were observed in the prevalence of atheroma plaques in any vascular territory between the different MVPA groups. Conclusions: Performing more than 60 min/week of VPA is associated with reduced odds for subclinical atherosclerosis in femoral or any vascular territory in adult men.