The effect of SARS-CoV-2 on the incidence of post-operative venous sinus thrombosis following skull base procedures.

PURPOSE: Sinus thrombosis is a common post-operative finding after posterior fossa surgery performed in the vicinity of the dural venous sinuses. The SARS-CoV-2 virus has been shown to confer an increased risk of venous thromboembolic events owing to eliciting a hyper-inflammatory and pro-thrombotic state. In this study, we examine the incidence of post-operative venous sinus thrombosis in patients undergoing peri-sigmoid posterior fossa surgery in the pre- and post-COVID era and investigate whether COVID infection confers an increased risk of sinus thrombosis. METHODS: A retrospective review of a single institution case series of patients underwent peri-sigmoid surgery (retrosigmoid, translabyrinthine, or far lateral) approach. Relevant clinical variables were investigated that may confer an increased risk of sinus thrombosis. RESULTS: A total of 311 patients (178 in the pre-COVID era, and 133 operated on after the pandemic began in March 2020) are included in the study. The composite incidence of sinus thrombosis seen on post-operative imaging was 7.8%. The incidence of sinus thrombosis in the pre-COVID cohort was N = 12 patients (6.7%) versus N = 12 (9%) in the post-COVID cohort (p = 0.46). A history of COVID infection was not shown to confer an increased risk of post-operative sinus thrombosis (OR: 0.61; 95% CI: 0.08-4.79, p = 0.64). Only a small number of patients (N = 7, 2.3%) required either medical or surgical intervention for post-operative sinus thrombosis. CONCLUSION: The overall incidence of post-operative sinus thrombosis is similar in the pre- and post-COVID era. The findings of this study suggest that COVID infection is not associated with a higher risk of venous sinus thrombosis.

Benign Thyroid Nodule Interventions: A Review and Imaging Considerations for the Interventional Radiologist.

Thyroid radiofrequency ablation (RFA) is a minimally invasive procedure that can be used to treat patients with benign thyroid nodules and is a good alternative to thyroidectomy or radioactive iodine. Thyroid RFA is commonly performed with local lidocaine or minimal/moderate sedation and has a minimal risk profile and few side effects. The efficacy of thyroid RFA has been well documented in the literature, with a volume reduction rate of 67 to 75% at 1 year. Another emerging technique for nodule size reduction is thyroid artery embolization which is a minimally invasive procedure that may be performed in patients with nodular goiters, particularly with substernal thyroid nodule extension, and who are either poor surgical candidates or do not want surgery. This article reviews thyroid RFA, focusing on the relevant preprocedural, procedural, and postprocedural imaging, as well as a discussion on the emerging role of thyroid artery embolization.

Thetis cells induce food-specific Treg cell differentiation and oral tolerance.

The intestinal immune system must establish tolerance to food antigens to prevent onset of allergic and inflammatory diseases. Peripherally generated regulatory T (pTreg) cells play an essential role in suppressing inflammatory responses to allergens; however, the antigen-presenting cell (APC) that instructs food-specific pTreg cells is not known. Here, we show that antigen presentation and TGF-ß activation by a subset of RORγt + antigen-presenting cells (APC), Thetis cells IV (TC IV), is required for food-induced pTreg cell differentiation and oral tolerance. By contrast, antigen presentation by dendritic cells (DCs) was dispensable for pTreg induction but required for T H 1 effector responses, highlighting a division of labor between tolerogenic TCs and pro-inflammatory DCs. While antigen presentation by TCs was required for food-specific pTreg generation both in early life and adulthood, the increased abundance of TCs in the peri-weaning period was associated with a window of opportunity for enhanced pTreg differentiation. These findings establish a critical role for TCs in oral tolerance and suggest that these cells may represent a key therapeutic target for the treatment of food-associated allergic and inflammatory diseases.