Ultra‐high‐field RF coil development for evaluating upper extremity imaging applications

The purpose of this study is to develop and evaluate a custom‐designed 7  T MRI coil and explore its use for upper extremity applications. An RF system composed of a transverse electromagnetic transmit coil and an eight‐channel receive‐only array was developed for 7  T upper extremity applications. The RF system was characterized and evaluated using scattering parameters and B₁⁺ mapping. Finite difference time domain simulations were performed to evaluate the B₁⁺ field distribution and specific absorption rate for the forearm region of the upper extremity. High‐resolution 7  T images were acquired and compared with those at 3 T. The simulation and experimental results show very good B₁⁺ field homogeneity across the forearm. High‐resolution images of musculotendinous, osseocartilaginous, and neurovascular structures in the upper extremity are presented with T₁ volumetric interpolated breath‐hold examination, T₂ double‐echo steady state, T₂* susceptibility weighted imaging (SWI), diffusion tensor imaging, and time‐of‐flight sequences. Comparison between 3  T and 7  T is shown. Intricate contextual anatomy can be delineated in synovial, fibrocartilaginous, interosseous, and intraosseous trabecular structures of the forearm, as well as palmar and digital vascular anatomy (including microvascular detail in SWI). Ultra‐high‐field 7  T imaging holds great potential in improving the sensitivity and specificity of upper extremity imaging, especially in wrist and hand pathology secondary to bone, ligament, nerve, vascular, and other soft or hard tissue etiology.     

Cutaneous granular cell tumor clinically mimicking ectopic breast diagnosed on fine needle aspiration cytology

Granular cell tumor (GCT) is a rare benign neoplasm of Schwannian origin which accounts of 0.5% of soft tissue tumors. Although the most common site for GCT is tongue, it can occur at any site. GCT presenting as cutaneous nodule is rare, however cases have been reported in literature. We hereby document a case of 30 year female with a hyper‐pigmented cutaneous nodule of anterior chest wall on the milk‐line mimicking as an ectopic breast, diagnosed as GCT on fine needle aspiration cytology. We also add a note on the differential diagnoses of GCT with differentiating cytological features to emphasize on the correct diagnosis of GCT pre‐operatively.     

The evolution of pancreatoduodenectomy

Till this day, surgery remains the only chance Pancreas of improving long-term survival in patients with periampullary and pancreatic head cancer. The procedure of choice in these cancers is pancreatoduodenectomy (PD). Associated with high morbidity, PD continues to pose a formidable challenge to pancreatic surgeons around the world. The falling mortality seen following the procedure has often been attributed to improvements in perioperative care - critical care, interventional radiology, and higher generation antibiotics. However, it would not be correct to totally ascribe these improvements only to the advancements in medical management. Developments in the understanding of the anatomical and pathophysiological factors that play a role in surgery around the pancreatoduodenal region have led to progressive modifications in the technique of pancreatoduodenectomy since it was first described in 1898. This review aims at highlighting the important milestones in the history of pancreatoduodenectomy leading to its progressive development, whilst providing a scientific basis.     

A risk prediction model for head and neck cancers incorporating lifestyle factors,HPV serology and genetic markers

Head and neck cancer is often diagnosed late and prognosis for most head and neck cancer patients remains poor. To aid early detection, we developed a risk prediction model based on demographic and lifestyle risk factors, human papillomavirus (HPV) serological markers and genetic markers. A total of 10 126 head and neck cancer cases and 5254 controls from five North American and European studies were included. HPV serostatus was determined by antibodies for HPV16 early oncoproteins (E6, E7) and regulatory early proteins (E1, E2, E4). The data were split into a training set (70%) for model development and a hold-out testing set (30%) for model performance evaluation, including discriminative ability and calibration. The risk models including demographic, lifestyle risk factors and polygenic risk score showed a reasonable predictive accuracy for head and neck cancer overall. A risk model that also included HPV serology showed substantially improved predictive accuracy for oropharyngeal cancer (AUC = 0.94, 95% CI = 0.92-0.95 in men and AUC = 0.92, 95% CI = 0.88-0.95 in women). The 5-year absolute risk estimates showed distinct trajectories by risk factor profiles. Based on the UK Biobank cohort, the risks of developing oropharyngeal cancer among 60 years old and HPV16 seropositive in the next 5 years ranged from 5.8% to 14.9% with an average of 8.1% for men, 1.3% to 4.4% with an average of 2.2% for women. Absolute risk was generally higher among individuals with heavy smoking, heavy drinking, HPV seropositivity and those with higher polygenic risk score. These risk models may be helpful for identifying people at high risk of developing head and neck cancer.