Varian Medical Systems (United States)

• Median nerve variants within the carpal tunnel have a pooled prevalence of 12%. • Bifid median nerve is the most frequently reported morphological variant. • No consistent association was found between anatomical variants and carpal tunnel syndrome. • Coexisting vascular or muscular anomalies may influence surgical complexity. • Preoperative imaging may aid anatomical identification, although clinical benefit remains uncertain. Anatomical variants of the median nerve (MN) within the carpal tunnel are clinically relevant due to their potential impact on the development, diagnosis, and surgical management of carpal tunnel syndrome (CTS). Reported prevalence estimates vary considerably across populations and study designs. To systematically review the literature and estimate the pooled prevalence of morphological variants of the median nerve within the carpal tunnel, and to assess their laterality, geographic distribution, and reported clinical implications. A systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines. MEDLINE, Scopus, Web of Science, CINAHL, and LILACS were searched from inception to November 2024. Google Scholar was used for supplementary screening of gray literature. Observational studies reporting the prevalence of MN variants identified through imaging, surgical exploration, or anatomical dissection were included. Methodological quality was assessed using the Anatomical Quality Assessment (AQUA) tool. Pooled prevalence estimates were calculated using a random-effects model (DerSimonian–Laird) with Freeman–Tukey double arcsine transformation. Sixty-three studies met eligibility criteria for qualitative synthesis, and 19 studies (n = 9,045 subjects) were included in the primary meta-analysis. The pooled prevalence of MN variants within the carpal tunnel was 12% (95% CI: 9–15%), with substantial heterogeneity (I² = 87%). Subgroup analysis showed similar prevalence in imaging-based studies (12%, 95% CI: 9–15%; I² = 87.8%). No clear laterality predominance was observed (right: 46%, 95% CI: 40–52%; I² = 0.0%; left: 53%, 95% CI: 48–59%; I² = 0.0%), whereas bilateral presentation demonstrated greater variability (21%, 95% CI: 6–36%; I² = 90.6%). Geographic subgroup analysis showed pooled prevalence estimates of 22% in Asia (95% CI: 13–31%; I² = 92.6%), 20% in Europe (95% CI: 14–27%; I² = 79.2%), and 18% in America (95% CI: 16–20%; I² = 19.4%). Morphological variants of the median nerve within the carpal tunnel are relatively common anatomical findings. Current evidence does not support their role as independent risk factors for CTS; however, their coexistence with vascular or muscular anomalies may influence local anatomical relationships and surgical complexity. Preoperative imaging may facilitate anatomical identification and surgical planning, although its impact on clinical outcomes and intraoperative complications remains uncertain and requires further prospective investigation.

Persistent left superior vena cava is a congenital variation of the thoracic venous system. Although it is often asymptomatic, its presence can complicate procedures such as central venous access, cardiac device implantation, and cardiothoracic surgery. Reported prevalence data are inconsistent and predominantly derived from populations with underlying cardiac pathology. This study seeks to provide a robust, evidence-based estimate of the prevalence of persistent left superior vena cava in populations not preselected for congenital heart disease. Additionally, it aims to quantify its principal anatomical configurations, including the laterality of the superior vena cava and the presence or absence of a bridging brachiocephalic vein. A systematic search was conducted using PubMed, Google Scholar, Scopus, and Web of Science. Studies documenting the prevalence of persistent left superior vena cava in populations not selected on the basis of congenital heart disease criteria were included. Statistical analysis was carried out using random-effects meta-analytic models. Eighteen studies (n = 169,835 individuals) were included. The pooled prevalence of persistent left superior vena cava was 0.61% (95% CI: 0.38-0.89), with substantial heterogeneity across studies. Subgroup analysis demonstrated higher detection rates in cadaveric investigations (2.08%) compared with interventional studies (0.38%), likely reflecting differences in detection sensitivity. Bilateral superior vena cava was observed in 0.32% of the population, whereas isolated persistent left superior vena cava occurred in 0.10%. A bridging brachiocephalic vein was present in approximately 0.11% of the total population. Although uncommon, persistent left superior vena cava is a reproducible component of thoracic venous morphology with embryological significance. Awareness of its anatomical configurations is important in diagnostic and procedural contexts, especially when a dilated coronary sinus is observed during imaging.

Objective.The generalized equivalent uniform dose (gEUD) is a well-established metric for radiotherapy dose optimization, particularly for normal tissues. However, the lack of theoretical clarity in its application has often led to empirical use in clinical practice. This study aims to reformulate gEUD-based optimization in a theoretical framework using the gEUD curve concept, and to develop a robust optimization strategy tailored for stereotactic radiation therapy (SRT), with a specific focus on bone and spinal metastases.Approach.We interpreted the gEUD as a smooth function of itsa-parameter, forming a continuous curve whose deformability decreases with increasinga. Based on this understanding, we proposed two methods: the multiple gEUD objective (MgEUDO) for optimizing the remaining volume at risk, and the selective gEUD objective (SgEUDO) for critical organs at risk. These methods were retrospectively evaluated in 22 patients who received five-fraction SRT (35 Gy total prescription).Main results.Using consistent gEUD-based optimization, all cases achieved clinically favorable dose distributions. Compared to conventional normal tissue objective constraints, the proposed strategy reduced mean dose to surrounding tissues by 10%, while improving tumor dose coverage by 0.6%. SgEUDO further achieved 39% and 37.5% mean dose reductions in the left and right kidneys, respectively.Significance.Our theoretical and practical refinement of gEUD optimization enables systematic control of dose distribution with reduced inter-planner variability. The combined MgEUDO and SgEUDO strategies provide a generalizable and clinically effective framework for high-precision radiotherapy.

Quality Assurance for online adaptive radiotherapy (oART) can be challenging. Several tests can demonstrate the dosimetric and position accuracy, but commercial phantoms are often not anatomically representative. The aim of this study was to investigate the accuracy of cone-beam computed tomography guided oART palliative and breast cancer trials by using a 3Dprinted thorax anthropomorphic phantom. An anthropomorphic phantom was 3Dprinted for this study which accommodates film through the spine, breast, heart, and lungs. Dose was measured for spine and breast treatment plans, whilst variations were simulated which can occur during treatment. Measurements were compared to calculated dose on the planning (pCT) and synthetic computed tomography (sCT) using gamma pass rate criteria of minimal 95% (for gamma of 4%/2mm). Differences between the mean gamma were tested for significance. Measurements done with positional and target volume changes showed no significant difference between the gamma analyses for the pCT and sCT (p=0.15), indicating a robust and safe workflow. For extreme variations, difference was found between gamma analyses for the pCT and sCT (p=0.051). Pass rates were all >95%, except for three measurements in which the sCT showed density errors up to 1000 HounsfieldUnits. This QA approach for oART, which used film measurements in a custom 3D-printed anthropomorphic phantom was able to validate the accuracy of the oART workflow when anatomical deviations arise and could be suitable as end-to-end test in the future.

PurposeSynchronous bilateral breast cancer (SBBC) presents significant radiotherapy planning challenges due to complex target volumes near critical organs. This study evaluated RapidArc Dynamic (RAD), a novel technique integrating dynamic arcs with static angle modulated ports (STAMPs) via simultaneous GPU‐accelerated optimization, against conventional volumetric modulated arc therapy (VMAT) for SBBC treatment planning and delivery efficiency.MethodsTen retrospective SBBC cases involving comprehensive nodal irradiation were planned using both multi‐arc VMAT (six arcs) and RAD (one arc plus six STAMPs) in Eclipse (v18.1) with AcurosXB. A prescription dose of 40.05 Gy in 15 fractions was normalized to PTV D95% = 95%. Paired Wilcoxon signed‐rank tests compared planning target volume (PTV) coverage (V95%, V105%) and organ‐at‐risk (OAR) doses, including lungs (V5Gy, V10Gy, V20Gy), heart (Dmean, V15Gy), and esophagus (Dmean, D0.03 cm3). Planning time, monitor units (MU), and measured delivery times were also assessed.ResultsRAD plans achieved clinical goals more frequently than VMAT plans (90% vs. 70% of endpoints). PTV V95% coverage was comparable between the two techniques. However, RAD significantly improved breast dose homogeneity (lower median PTVp V105%; p < 0.05) and OAR sparing. Notably, RAD reduced median lung V5Gy by 9.7% (p < 0.001) and esophageal D0.03 cm3 by 5.4 Gy (p = 0.002). RAD significantly reduced planning time (avg 16 vs. 39 min), mean MU (1654 vs. 2268; ∼30% reduction), and mean measured delivery time (2.2 vs. 5.8 min; ∼62% reduction).ConclusionFor SBBC radiotherapy, RAD demonstrated significant dosimetric improvements over conventional VMAT, particularly reducing low‐dose lung and high‐dose esophageal irradiation while enhancing target homogeneity. The substantial gains in planning and delivery efficiency further establish RAD as a highly advantageous technique for managing these complex cases.

Abstract The Faroe Islands are home to descendants of a North Atlantic founder population with a unique history shaped by both migration and periods of relative isolation. Here, we investigate the genetic diversity, population structure, and demographic history of the islands by analyzing whole genome sequencing data from 40 participants in the Faroe Genome Project. This represents the first whole genome sequencing panel of this size from the Faroe Islands. We observed numerous putatively functional private alleles, including stop gain variants and high impact missense variants in the cohort. Faroese individuals had a higher proportion of their genomes contained in long runs of homozygosity than other European groups, including Finnish, suggesting a more recent or stronger bottleneck in the Faroese population. Signals of positive selection were identified at loci containing genes that play roles in vitamin D and dietary fat absorption and DNA repair, while increased diversity on lactase persistence haplotypes was observed. Fine-scale analysis of haplotype structure in modern and ancient European genomes revealed genetic affinities with ancient Iron Age individuals from the North and West of Europe, providing evidence for potential contributions to the Faroese gene pool from Celtic and Viking populations as well as information about the temporal order in which these events happened. This study highlights the impact of evolutionary processes, such as ancient admixture, founder events, and positive selection, on the present-day genetic architecture of North Atlantic founder populations like the Faroe Islands.

The coracobrachialis muscle (CB) is a phylogenetically conserved component of the anterior compartment of the upper limb, offering critical insights into evolutionary anatomy, developmental biology, and human morphological variation. This mini review synthesizes findings from comparative anatomical studies, embryological data, cadaveric dissections, and clinical reports to explore the CB's morphology, ontogeny, and medical relevance. Among tetrapods, the CB consistently originates from the coracoid process and inserts into the humerus, with interspecies morphological adaptations reflecting specific locomotor functions such as climbing, grasping, or digging. In humans, embryological studies confirm a common developmental origin with the biceps brachii, accounting for the frequent occurrence of variant configurations, including multiple heads and accessory slips such as the coracobrachialis longus (CBL) and brevis (CBB). These variants may contribute to clinical conditions such as musculocutaneous nerve entrapment+ or subcoracoid impingement. They may also be employed in reconstructive surgical procedures. A deeper understanding of CB morphology within an evolutionary framework improves anatomical interpretation, enhances clinical safety, and reduces diagnostic ambiguity. This review highlights the significance of integrating evolutionary and developmental perspectives in the study of human muscle variation.

ABSTRACT Vitamin D is vital for physiological functions and is obtained primarily through sunlight and a few dietary sources. With limited sunlight exposure, the Faroe Islands face challenges in maintaining sufficient levels of vitamin D, while the Faroese population has documented the highest incidence and prevalence of inflammatory bowel disease worldwide. This study investigates vitamin D status among Faroese adults and its association with inflammatory bowel disease as well as other self-reported diseases in a subset of the Faroe Genome Project 2. Cross-sectional study including 1,748 participants aged 18–86 years. Among participants, 74.3% maintained sufficient vitamin D levels, while 25.7% were insufficient (<50 nmol/l). Individuals with conditions like hypertension, type 2 diabetes, and inflammatory bowel disease showed significantly higher rates of vitamin D sufficiency compared to those without these conditions. Notably, 83% of participants with inflammatory bowel disease had sufficient vitamin D. Our data reveal higher vitamin D levels compared to previous studies in the Faroe Islands. Furthermore, contrary to our hypothesis, our data shows higher vitamin D levels for participants reporting diseases including inflammatory bowel disease, indicating patients with inflammatory bowel disease can attain high vitamin D levels, which is of considerable clinical importance.