Background/Objectives: The stellate ganglion (SG), formed by the fusion of the inferior cervical and first thoracic sympathetic ganglia in approximately 80% of individuals, plays crucial roles in cardiac innervation, pain management, and autonomic regulation. This review examines the anatomical variations, histological structure, clinical applications, and therapeutic implications of the SG and stellate ganglion block (SGB), presenting original high-resolution magnetic resonance imaging (MRI) evidence of SG visualization, an underutilized approach in autonomic nervous system research. Methods: We conducted a comprehensive literature review of anatomical, physiological, and clinical studies on the SG, incorporating original anatomical dissections and high-resolution MRI. Contemporary research on SGB applications, complications, and mechanisms of action was analysed and correlated with imaging characteristics. Results: The SG demonstrates significant anatomical variability, including the presence of intermediate ganglia, accessory nerve pathways, and variable relationships with surrounding vascular structures. Our original MRI imaging consistently identified the SG at the thoracic inlet, anterior to the neck of the first rib, lateral to the longus colli muscle, and posterior to the vertebral artery, demonstrating that advanced imaging can reliably visualize this critical autonomic structure and its anatomical variants. Histologically, it contains typical sympathetic architecture, comprising postganglionic neurons, satellite glial cells, and specialized SIF cells that modulate ganglionic transmission. SGB shows therapeutic efficacy across diverse conditions, including cardiac arrhythmias, chronic pain syndromes, post-traumatic stress disorder, sleep disorders, and immune dysfunction. The procedure’s mechanisms involve both direct sympathetic blockade and complex neuroimmune pathways that affect central autonomic centers and lymphoid organs. Complications include vascular injury, pneumothorax, and nerve blocks affecting the recurrent laryngeal and phrenic nerves. Conclusions: The SG represents a critical autonomic structure with expanding clinical applications. This work advances the field by demonstrating that high-resolution MRI can consistently and non-invasively visualize the SG and its anatomical variations, knowledge previously mostly limited to cadaveric studies. Understanding these imaging-defined anatomical variations is essential for optimizing therapeutic interventions. Advanced imaging guidance integrated with comprehensive anatomical knowledge is crucial for maximizing efficacy while minimizing complications in stellate ganglion block procedures.

The internal jugular vein (IJV) is of utmost importance during various surgical and endovascular approaches, including central access. It descends through the parapharyngeal space, carotid triangle, and sternocleidomastoid region. The anatomical variables of the IJV are mainly related to its calibre and dominance, number of venous channels (i.e., duplications and fenestrations), and compression sites. Specific compressions of the IJV are not exclusively due to the jugular nutcracker between the styloid process (SP) of the temporal bone and the C1 transverse process, which, in turn, should not be granted the eponym of Eagle. The possible morphologies of the SP and ossified stylohyoid chain are discussed here. Additionally, the digastric and sternocleidomastoid muscles, the hyoid, and the distorted carotid arteries may compress the IJV, thereby raising intracranial pressure. Here, a case is documented with a long inferior petrosal sinus adjacent to the IJV, both compressed into the C1–styloid nutcracker, which is an absolute novelty. Multiple compression sites of the IJV are supported here with original evidence. All anatomical variables of the IJV are relevant, as they may lead to stenoses or interfere with IJV cannulation. In rare cases of IJV agenesis, multiple compression sites on the opposite side may significantly alter bilateral cerebral drainage. Different methods may be used to decompress a stenotic IJV, including styloidectomy. In conclusion, the anatomical variables of the IJV should be acknowledged by practitioners and documented on a case-by-case basis.

Background/Objectives: The suprasternal notch (SN) is the conventional landmark for front-of-neck airway access and anterior cervical surgery, yet the great vessels may extend to or above it. To our knowledge, no previous study has jointly classified the aortic arch (AA), brachiocephalic trunk (BCT), left brachiocephalic vein (LBCV), and sternoclavicular joint (SCJ) configuration relative to the SN in a single adult cohort. Methods: In this single-centre retrospective study, 100 consecutive adult computed tomography angiography (CTA) studies were reviewed. Using a horizontal SN reference plane, the AA, BCT, and LBCV were each graded as mediastinal, cervicomediastinal, or cervical/high-riding; the bilateral SCJ manubrial joining grade was scored on four levels and integrated into three categories (mild, clear, marked). Two observers independently classified all cases (weighted Cohen kappa = 0.89). Associations were assessed with Spearman correlation and chi-square tests. Results: The BCT was the most variable structure, cervical/high-riding in 49% and reaching or crossing the SN in 64%; the AA and LBCV were cervical/high-riding in 3% and 5%, respectively. Complete SCJ manubrial joining was absent in all cases, and the integrated SN space was marked in 15% of cases. Cervical/high-riding BCT was more frequent in women (63.5% vs. 33.3%; p = 0.005). Five of six pairwise correlations remained significant after Benjamini–Hochberg adjustment, with the strongest association for AA–BCT (rho = 0.406). Conclusions: The BCT was the principal great vessel extending to or above the SN in this cohort, whereas cervical/high-riding AA and LBCV were uncommon. The SN-referenced classification provides a reproducible descriptive framework for this topography. These findings represent cohort frequencies rather than population-based prevalence estimates, and their potential procedural relevance requires prospective validation.

Background/Objectives: New-onset atrial fibrillation (NOAF) is a common complication of acute coronary syndrome (ACS) and is associated with adverse clinical outcomes. Although systemic inflammation has been implicated in the pathogenesis of NOAF, the contribution of different inflammatory biomarkers and their incremental value beyond established clinical factors remain incompletely understood. This study aimed to examine the association between inflammatory biomarkers and NOAF in patients hospitalized with ACS and to assess their contribution beyond established clinical risk factors. Materials and Methods: This prospective single-center cohort included 100 consecutive patients hospitalized with ACS and without a documented history of atrial fibrillation. Comprehensive demographic, clinical, laboratory, echocardiographic, and angiographic data were collected. Systemic inflammatory status was assessed using C-reactive protein (CRP), the neutrophil-to-lymphocyte ratio (NLR), the monocyte-to-lymphocyte ratio (MLR), and the systemic immune-inflammation index (SII). Univariable and multivariable logistic regression analyses were performed to identify factors associated with NOAF. The incremental contribution of inflammatory biomarkers to apparent in-sample model discrimination was explored using receiver operating characteristic (ROC) curve analysis and DeLong’s test. Sensitivity analyses were performed according to the timing of NOAF occurrence. Results: NOAF occurred in 33 of 100 patients (33%) during hospitalization. Patients who developed NOAF were older and exhibited greater left atrial enlargement, more extensive coronary artery disease, and higher inflammatory biomarker levels. In univariable analyses, CRP, NLR, and SII were significantly associated with NOAF. In exploratory multivariable analyses adjusted for clinically selected covariates, CRP remained associated with NOAF (adjusted OR 1.71, 95% CI 1.08–2.91; p = 0.031), whereas NLR, SII, NT-proBNP, and troponin did not retain statistically significant associations. CRP demonstrated the highest numerical improvement in model discrimination, although the increase in AUC compared with the baseline clinical model was not statistically significant. Sensitivity analyses confirmed the consistency of the association between CRP and NOAF. Conclusions: In this exploratory single-center cohort, CRP remained associated with NOAF after adjustment for clinically selected covariates, supporting further investigation of the relationship between systemic inflammation and NOAF development. These findings require confirmation in larger cohorts with internal and external validation.