Search Results (85)

Background: Endovascular treatment has become the major choice for treating intracranial aneurysm (IA). The development of novel endovascular devices for IA treatment is, therefore, socially important. For this purpose, a preclinical animal model to test a prototype of devices plays a crucial role. The major problems regarding currently used preclinical animal models, mainly in medium-to-large animals, are the expense and the lack of IA pathology, as they only mimic the morphological aspect. Methods: Sprague–Dawley rats were used, and the new bifurcation was formed via end-to-side anastomosis of carotid arteries. An aneurysm lesion induced at the newly formed bifurcation site was macroscopically assessed. Endovascular coiling of the induced aneurysm was then done. Results: An aneurysm lesion with a balloon-like shape, as in human cases, was induced at the newly formed bifurcation site. Some of the induced lesions spontaneously ruptured. Endovascular coiling was successfully done by using the micro-catheter and coil used at the clinical site. Conclusions: The rat model of IAs established here provides a novel platform contributing to the development of endovascular devices to treat IAs and, therefore, significantly facilitates the development of devices to achieve more effective treatment. Full article

Introduction: The retropharyngeal carotid artery (RCA) is a rare anatomical variant where the carotid artery resides in the retropharyngeal space. The co-occurrence of RCA and significant atherosclerotic stenosis of the carotid bifurcation is even rarer. Recognizing this anatomy is crucial because of the increased risk of adverse events during procedures such as intubation or oropharyngeal surgery. Furthermore, differentiating between the fixed and dynamic forms is essential for guiding appropriate diagnostic and therapeutic strategies. A scoping review was undertaken, and two cases of RCA and significant internal carotid artery stenosis requiring a surgical approach were presented. Materials and Methods: EMBASE and OVID were systematically searched for studies reporting data on RCA and significant internal carotid artery stenosis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) was followed, and we presented two case reports of RCA and significant internal carotid artery stenosis requiring surgical treatment, treated at the Division of Vascular Surgery, IRCCS MultiMedica, Sesto San Giovanni, Milan, Italy. Results and Discussion: Among the 22 papers identified by the scoping review, 6 case reports were ultimately included in the analysis, supplemented by our two cases. The review and the added cases highlight significant heterogeneity in the clinical presentation and management of RCA with stenosis. Therapeutic options include carotid endarterectomy (CEA), transfemoral carotid artery stenting (TF-CAS), and transcarotid artery revascularization (TCAR). Also, the diagnostic with dynamic 3D-CT angiography during swallowing would be important in some symptomatic cases to document mechanical compression by the hyoid bone or thyroid cartilage (dynamic RCA), which standard static imaging failed to detect. Conclusions: Due to the rarity of the condition, no high-level evidence (RCTs) exists. Treatment decisions are based on the qualitative assessment of anatomical risk and isolated case reports. Standard interventions (CEA and TF-CAS) are generally considered high-risk. The final management choice must be individualized based on technical feasibility, neurological risk, and the determination of whether the pathology is fixed or dynamically compressive. Full article

Understanding the hemodynamics of the carotid artery is essential for assessing atherosclerotic disease progression and identifying regions vulnerable to plaque formation. Background: Disturbed flow patterns and abnormal shear stresses, particularly near the carotid bifurcation, are known to influence endothelial dysfunction; therefore, this study aims to quantify the impact of patient-specific carotid artery geometry on key hemodynamic parameters associated with atherosclerotic risk. Methods: Four patient-specific carotid artery geometries were reconstructed from medical imaging data, processed using MIMICS, and analyzed using computational fluid dynamics in ANSYS Fluent, with blood modeled as an incompressible non-Newtonian fluid using the Carreau–Yasuda viscosity model under pulsatile flow conditions; velocity streamlines, pressure distribution, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) were evaluated at early systole, peak systole, and peak diastole. Results: The simulations revealed complex flow behaviour, including flow reversal, pressure build-up, and low-shear regions concentrated near the carotid bulb and bifurcation, with TAWSS consistently identifying low-shear zones (<1 Pa) across all geometries and OSI exhibiting pronounced directional oscillations in models with increased curvature and wider bifurcation angles. Conclusions: These findings demonstrate that geometric characteristics such as bifurcation angle, vessel tortuosity, and asymmetry play a critical role in shaping local haemodynamics, underscoring the utility of patient-specific CFD analysis as a diagnostic and predictive tool for atherosclerotic risk assessment and supporting more informed, personalized clinical decision-making. Full article

Background/Objectives: Carotid body paragangliomas, commonly referred to as Carotid Body Tumors (CBTs), are rare, highly vascular paragangliomas arising at the carotid bifurcation and pose significant surgical challenges due to their proximity to critical neurovascular structures. Optimal management remains debated, particularly for large or complex lesions. This study aims to present a structured neurosurgical operative workflow as an educational and practical resource to help young surgeons understand operative decision-making and technical execution from a neurosurgical perspective. Methods: We retrospectively reviewed patients diagnosed with CBTs and identified three cases that underwent microsurgical resection by a single neurosurgeon. Clinical presentation, radiographic findings, operative strategies, intraoperative microsurgical techniques, and postoperative outcomes were analyzed. Surgical procedures for all three cases are further illustrated with technical video demonstrations highlighting meticulous microsurgical techniques performed by a single neurosurgeon. Results: All three patients presented with either incidental or slowly progressive neck masses, with imaging demonstrating classic splaying of the internal and external carotid arteries. One patient exhibited elevated catecholamine metabolites, while another had a familial history of paragangliomas. Preoperative embolization was successfully performed in all three cases. Complete tumor resection was achieved in each patient. One patient developed post-embolization embolic ischemic changes with transient neurological deficits that were resolved within several hours. No permanent cranial nerve deficits, vascular injuries, or tumor recurrences were observed. Pathology confirmed paraganglioma in all cases. Conclusions: Surgical resection remains an effective treatment for CBTs, which are commonly managed by vascular or head and neck surgeons. This case series illustrates the technical feasibility of CBT resection using a comprehensive neurosurgical strategy that integrates endovascular preparation, cerebral perfusion assessment, and meticulous microsurgical technique. Rather than proposing novel surgical innovation, this report aims to provide a structured operative framework and detailed video-based illustration of complex carotid bifurcation management from a neurosurgical perspective. Full article

Introduction: Ischemic stroke in young adults is uncommon and is frequently associated with rare etiologies, including autoimmune diseases and vasculitis. Takayasu arteritis (TA) is a chronic inflammatory large-vessel arteriopathy involving the aorta and its major branches and may result in cerebral ischemia due to arterial stenosis or thrombosis. Case Presentation: We report the case of a 26-year-old woman with a history of suspected rheumatoid arthritis and Lyme disease who presented with acute left-sided hemiparesis and dysarthria. At admission, large-vessel vasculitis had not yet been suspected, and the patient was treated according to standard acute stroke protocols. Computed tomography angiography (CTA) revealed occlusion of the right middle cerebral artery bifurcation and the right common carotid artery, with inflammatory changes involving the brachiocephalic trunk and subclavian arteries. Intravenous thrombolysis (iv rtPA) was followed by mechanical thrombectomy (MT), resulting in neurological improvement. Outcome: Further diagnostic work-up confirmed TA, and immunosuppressive therapy with cyclophosphamide and infliximab was initiated. Conclusion: This case underscores the importance of considering inflammatory large-vessel disease in young patients presenting with acute ischemic stroke and illustrates that endovascular reperfusion may be feasible in this clinical setting. Full article

Mean corpuscular volume ($MCV$) is a routinely measured hematological parameter that influences blood viscosity by altering red blood cell volume and packing density. Although $MCV$ is physiologically linked to hemorheological behavior, to the authors’ knowledge, its direct role in modulating large-artery hemodynamics has not been systematically quantified. This study introduces an $MCV$-driven effective Newtonian viscosity mode to evaluate the first-order impact of $MCV$ variation on carotid bifurcation flow. Rather than employing shear-dependent constitutive laws, blood viscosity was scaled through an $MCV$-based formulation, yielding three Newtonian fluids corresponding to clinically relevant $MCV$ levels of 70, 90, and 110 fL. Pulsatile CFD simulations were performed in four idealized carotid bifurcation geometries (40°, 50°, 65°, and 100°) to assess the combined influence of vascular geometry and $MCV$-dependent viscosity variation. Hemodynamic indices including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT) were quantified, and a two-way analysis of variance (ANOVA) was employed to distinguish the relative contributions of geometric configuration and $MCV$. Across the investigated $MCV$ range, increasing $MCV$ produced a geometry-dependent modulation of shear-based indices, with TAWSS increasing by up to approximately 11%, while OSI and RRT decreased by about 20–25% and 10%, respectively, particularly in geometries exhibiting pronounced flow separation. Although vascular geometry remained the dominant determinant of overall hemodynamic patterns, $MCV$-induced viscosity scaling significantly modulated low-shear and recirculation regions. These findings suggest that $MCV$-dependent viscosity scaling can complement patient-specific hemodynamic assessments and provide a rational baseline for future shear-dependent and personalized rheological modeling frameworks. Full article

Introduction: Accurate knowledge of the external carotid artery (ECA) anatomy is essential for head and neck surgery, interventional procedures, and imaging interpretation. Although its branching pattern is classically described as relatively constant, clinically relevant anatomical variations are frequently encountered. Cadaveric dissection remains fundamental for identifying rare vascular configurations. Materials and Methods: During an anatomical teaching dissection of a 72-year-old male cadaver, a right-sided lateral cervicotomy was performed to expose the carotid sheath. After mobilisation of the sternocleidomastoid muscle, the ECA and its proximal branches were skeletonised, allowing detailed three-dimensional assessment of their origin, calibre, and neurovascular relationships. Results: The superior thyroid artery originated from the proximal segment of the external carotid artery, in close proximity to the carotid bifurcation. The main anatomical finding was a lingual artery of relatively small initial calibre exhibiting an atypical superior trajectory: after its origin, it crossed superior to the hypoglossal nerve before continuing toward the tongue. This configuration differs from classical descriptions and modified the anatomical arrangement of Beclard’s and Pirogoff’s triangles, creating a potential site of close neurovascular contact. Conclusions: This cadaveric study describes a rare trajectory-based variant of the external carotid artery characterised by a lingual artery crossing superior to the hypoglossal nerve. Awareness of such rare patterns is essential for improving anatomical interpretation and enhancing surgical safety in the head and neck region. Full article

Background/Objectives: This study aimed to investigate the relationship between carotid artery anatomy and geometry and white matter hyperintensities (WMH) and to determine whether it is a risk factor for the disease. Methods: The geometry and anatomy of both carotid arteries were evaluated with the three-dimensional vessel model obtained from the computed tomography angiography (CTA) data, and the segmentation software calculated the geometrical features of the arteries. In this model, vascular diameter, vascular cross-sectional area, carotid bifurcation and internal carotid artery (ICA) angles, as well as ICA tortuosity index (TI) measurements of the common carotid artery (CCA) and ICA were determined. Results: Compared with the non-WMH group, increased carotid bifurcation and ICA angle and higher ICA TI values were found in the WMH group (p < 0.001). In multivariate regression analysis, increased carotid bifurcation angle, higher ICA TI values, age, hypertension, and stroke history were identified as independent risk factors for the development of WMH (p < 0.05). In addition, age, carotid bifurcation angles and ICA angles were found to be associated with the severity of WMH (p < 0.05). Conclusions: Considering the vascular pathologies involved in the pathogenesis of WMH, identifying these risk factors may help determine individuals who are at an increased risk. Full article

Objective: Evaluate the efficacy and safety following intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in patients with diabetic macular oedema (DME). Methods: To evaluate retinal microvascular remodelling and photoreceptor metrics using adaptive optics (AO) alongside systemic vascular status assessed by brachial/aortic hemodynamic and carotid ultrasound. We conducted a single-centre longitudinal study including twenty-one patients with DME. The following four diagnostic visits were performed: baseline (V1, no anti-VEGF treatment), 2–3 months (V2), 6–8 months (V3), and 12–14 months (V4). Adaptive optics (rtx1) measured foveal cone number (N) and regularity (Reg) within a standardised 80 × 80 µm window, and superior temporal retinal arteriole morphology after the first bifurcation (vessel diameter [VD], lumen diameter [LD], wall thickness [WT], wall-to-lumen ratio [WLR], and wall cross-sectional area [WCSA]). SphygmoCor provided peripheral (brachial) and central (aortic) pressures, augmentation pressure (AP), augmentation index (AIx), and carotid–femoral pulse wave velocity (PWV and PWVHR heart rate adjusted). Carotid ultrasound assessed intima–media thickness (IMT), carotid lumen diameter (CLD), and IMT/CLD ratio (IMTLR) 2 mm proximal to the bifurcation in diastole. Visual acuity (Visus), intraocular pressure (IOP), and central retinal thickness (CRT) were obtained at each visit. Results: In the treated eye (TE), WLR showed a significant overall change (Friedman p = 0.007), with a modest V4 vs. V1 increase (Wilcoxon p = 0.045); LD also varied across visits (Friedman p = 0.034). Cone metrics improved as follows: Reg increased over time (Friedman p = 0.019), with a significant rise at V4 vs. V1 (p = 0.018), and cone number increased at V3 vs. V1 (p = 0.012). Functional/structural outcomes improved as follows: visual acuity increased at V3 (p = 0.009) and V4 (p = 0.028), while CRT decreased at V3 (p = 0.002) and V4 (p = 0.030); IOP remained stable compared to V1. Systemic hemodynamics was largely unchanged; small fluctuations in DBP and cDBP across V1–V4 were observed (Friedman p = 0.034 and p = 0.022, respectively), whereas AIx, AP, PWV, and PWVHR showed no significant trends. Carotid IMT, CLD, and IMTLR did not change significantly across visits, supporting systemic vascular safety. Conclusions: Intravitreal anti-VEGF therapy in DME was associated with improvements in photoreceptor organisation and macular structure/function, with AO-derived arteriolar remodelling detectable over time, and no adverse changes in large-artery structure. These findings support ocular efficacy and systemic vascular safety; confirmation in larger cohorts is warranted. Full article

Background/Objectives: The ascending pharyngeal artery (APA) exhibits considerable variability in origin. Understanding its anatomy is essential for head and neck surgery, endovascular procedures, and skull base approaches. This study aimed to (1) systematically characterize APA origin sites, (2) evaluate bilateral patterns, and (3) establish a comprehensive sequential classification system for external carotid artery (ECA) branching. Methods: Bilateral computed tomography angiography assessment was performed in 85 patients (170 carotid axes; 54 men, 31 women; mean age 69 ± 10 years). APA origins were classified into six types: Type 0 (absent), Type I (ECA medial wall), Type II (ECA posterior wall), Type III (occipitopharyngeal trunk), Type IV (internal carotid artery), and Type V (other origins). A novel sequential classification system (S-types) documented the complete ECA branching order. Results: APA was absent in 14.71% of cases; APA’s absence or internal carotid origin was noted in 19.41% of cases. Type I occurred in 26.47%, Type II in 35.88%, Type III in 17.06%, Type IV in 4.71%, and Type V in 1.18%. Forty distinct S-types were identified, representing the most comprehensive documentation of ECA branching diversity. No statistically significant side-related (χ² = 42.12, p = 0.379) or gender-related (χ² = 49.81, p = 0.138) differences were found. Twenty-three types occurred in fewer than five cases each. Conclusions: This first comprehensive sequential classification system reveals extraordinary anatomical diversity in ECA branching patterns. The absence of predictable side or gender patterns necessitates bilateral preoperative imaging for surgical planning. Full article

Background: Diabetic neuropathy affects almost half of diabetic patients, yet the relative contributions of metabolic, vascular and clinical factors remain controversial. We aimed to investigate which risk factors are more associated with reduced corneal nerve fiber length (CNFL). Methods: This is a cross-sectional study of 30 patients with type 2 diabetes. We assessed metabolic parameters (HbA1c, lipids), vascular measurements (Doppler ultrasonography of carotid and ophthalmic arteries, central vessel density measured by optical coherence tomography angiography), and corneal epithelial thickness. We explored the data using network analysis, then applied penalized mixed-effect regression (in which $\beta$ represents the standardized coefficients with mean 0 and unit standard deviation), followed by generalized additive models and polynomial transformations. Results: Penalized regression identified vascular parameters as dominant predictors: carotid plaques ($\beta$ = −0.609) and intima-media thickness ($\beta$ = −0.574) showed the strongest associations with CNFL. Traditional metabolic markers including HbA1c failed to meet selection thresholds. Bifurcation velocity ($\beta$ = −0.313) and corneal sensitivity measures ($\beta$ = 0.278–0.135) were also significant. The non-linear modeling showed complex vascular–structural interactions. Conclusions: Vascular compromise, particularly carotid disease, had the highest association with CNFL in our cohort. Thus, our study reports a higher effect of vascular parameters than HbA1c in patients with a longer history of diabetes. This may reflect the progression of diabetic complications, where initial metabolic insults are followed by vascular pathology as the primary driver of end-organ damage. Our findings highlight the need for carotid artery screening in diabetic patients for a better estimation of the neuropathy risk. Full article

Superparamagnetic iron oxide nanoparticles (SPIONs) have shown promise across a wide range of biomedical applications, including targeted drug delivery, magnetic hyperthermia, magnetic resonance imaging, and regenerative medicine. In the context of local tumor therapy (Magnetic Drug Targeting, MDT) SPIONs can be functionalized with chemotherapeutic agents and accumulated at tumor sites using an externally applied magnetic field. To achieve effective drug accumulation and therapeutic efficacy, precise positioning of the accumulation magnet relative to the tumor is essential. To address this need, we propose a dual-modality ultrasound imaging approach combining magnetomotive ultrasound (MMUS) and passive cavitation mapping (PCM). MMUS detects magnetically induced displacements to localize SPIONs embedded in elastic tissue, while PCM monitors cavitation emissions from circulating SPIONs under focused ultrasound exposure. In addition to detection, PCM has the potential to enable feedback-based control of cavitation exposure, allowing cavitation parameters to be kept within a safe regime. The dual imaging modality approach was validated using standard phantoms and a complex carotid bifurcation tumor flow phantom fabricated via 3D printing. Experimental results demonstrate the first coordinated spatiotemporal imaging of MMUS and PCM within the same anatomical model, resolving the key bottleneck of SPIONs monitoring in blood vessels/tissue. This demonstrates the strong potential of complementary MMUS and PCM imaging for monitoring in preclinical and clinical MDT settings. Full article

The carotid body—a chemoreceptive derivative of the neural crest located at the bifurcation of the carotid artery—has been studied for over 282 years. The history of research into this small but vital organ is full of unexpected turns and offers many valuable lessons. Initially considered part of a unified system of paraganglia performing the endocrine function, the carotid body was later reclassified and recognized as a chemosensory organ. This article highlights the key controversies encountered by past researchers. These contradictions though largely forgotten, remain unresolved. The aim of our article is to propose a unified model of the carotid body that integrates its endocrine and chemosensory structural aspects. As we show, the main problem in studying the carotid body was its isolated investigation, detached from other organs of the sympathoadrenal system. Only a comprehensive analysis of the carotid body with other components of this system has allowed researchers to form a more complete understanding of both the structure and function of these formations. Contrary to the prevailing view of the carotid body as the main peripheral chemoreceptor organ, it may also perform endocrine functions during certain periods of human ontogeny. It is these potential functions that may explain the presence of certain morphological structures in the carotid body, the significance of which has until recently remained a mystery. Full article

Pulsatile blood flow generates complex wall shear stress (WSS) patterns at the carotid bifurcation, which critically regulate endothelial function and structure. While physiological pulsatile WSS (PWSS) is essential for maintaining vascular health, low oscillatory WSS (OWSS) near the carotid sinus is closely associated with endothelial dysfunction, atherosclerotic plaque formation, and stenosis. Reproducing these hemodynamic conditions in vitro is therefore crucial for investigating endothelial mechanobiology and elucidating the pathogenesis of atherosclerosis. Although microfluidic technologies have emerged as promising platforms for simulating either pulsatile or oscillatory WSS, a system capable of simultaneously replicating both characteristic waveforms—as found in vivo at the carotid bifurcation—remains undeveloped. In this study, we designed a variable cross-section microfluidic channel using Computational Fluid Dynamics (CFD) simulations. Numerical results demonstrate that the optimized channel accurately reproduces low OWSS at a stepped section emulating the carotid sinus, alongside high PWSS in a downstream uniform section. Vortex formation induced by the step structure is identified as key to generating low OWSS, influenced by step height, channel width ratio, and input flow rate. This work provides a novel and robust methodology for designing microfluidic systems that mimic complex hemodynamic microenvironments, facilitating future studies on the interplay between distinct WSS patterns and endothelial dysfunction. Full article

Background: Accurate localization of internal carotid artery (ICA) occlusion is critical for optimizing endovascular thrombectomy (EVT) strategies. Conventional multiphase CT angiography (mCTA) often omits the carotid bifurcation in delayed phases, limiting differentiation between true cervical ICA occlusion and pseudo-occlusion. Methods: We retrospectively analyzed 56 acute ischemic stroke patients with ICA occlusion who underwent EVT and extended-range mCTA between 2016 and 2020. The scan range of the second and third arterial phases was modified to include the carotid bifurcation. Imaging patterns were evaluated to distinguish bifurcation stenosis with superimposed occlusion from proximal ICA occlusion, and to infer thrombus location by comparing arterial opacification levels across phases. Results: Extended mCTA significantly improved visualization of ICA enhancement patterns in delayed phases (p < 0.001). Cases with bifurcation stenosis showed consistently lower and stable opacification levels across phases, whereas proximal ICA occlusion demonstrated progressive contrast advancement. Distal occlusion, particularly beyond the ophthalmic artery, showed higher opacification. Including the carotid bifurcation increased scan length by ~10%, with acceptable radiation exposure. Conclusions: Incorporating the carotid bifurcation into delayed mCTA phases enhances the ability to differentiate occlusion subtypes and estimate thrombus location. This refined imaging approach enables better EVT planning, including device selection and procedural timing, thereby improving patient outcomes in acute stroke care. Full article