Paragangliomas are rare neuroendocrine neoplasms. The most common form of these tumors in head and neck are non-functional carotid body tumors. These neoplasms may present an extensive growth and compromise vital neurovascular structures in the neck, such as carotid vessels. Carotid body tumors usually present clinically as painless neck masses and occur most frequently in adults averaging 45 to 50 years, being the majority of these tumors unilateral and only 5% of all cases bilateral. The main treatment for carotid body paragangliomas is surgical resection, which can be extremely challenging due to tumor hypervascularity and significant blood loss. We present a bilateral carotid body tumor case in a 61-year-old woman who presented due to a pulsatile and painless mass in the right carotid region of the neck of 1-year of evolution. The tumor was found encasing the external carotid artery and classified as Shamblin II. A novel approach for preoperative management was performed, placing a covered graft-stent in the right common and proximal (C1) internal carotid arteries in order to splint and provide structural protection for carotid vessels during surgical resection and temporarily reduce blood flow of the carotid body tumor.

OBJECTIVES: A proof-of-concept study using thrombolysis with catheter-directed tissue plasminogen activator (tPA) and pulmonary angiography imaging was performed to visualize perfusion deficits and reperfusion/therapeutic effects of tPA. DESIGN: A prospective, open-label, compassionate study. Descriptive statistics were presented for categorical variables and as means with sds for continuous variables. The Wilcoxon test was used to determine the differences between the two-related samples and a t test for continuous variables. Statistical significance was set at p value of less than 0.05. Agreement between observations was evaluated using the Kappa Cohen index and overall agreement using the Fleiss Kappa coefficient. SETTING: A single COVID-19 ICU of Mexico´s General Hospital Dr Eduardo Liceaga. SUBJECTS: Fifteen patients with severe Delta variant severe acute respiratory syndrome coronavirus 2 infection, 18–75 years old, requiring mechanical ventilation with a persistent Fio2 requirement of 70% or higher and Pao2/Fio2 ratio (or imputed ratio) less than 150 for more than 4 hours. The coagulation inclusion criteria were International Society on Thrombosis and Haemostasis score greater than 5, and presence of a d-dimer greater than 1,200, with viscoelastic testing using rotational thromboelastometry (Instrumentation Laboratories, Mexico City, Mexico) showing both hypercoagulability (EXTEM amplitude at 5 min > 65 FIBTEM > 30) and hypofibrinolysis (EXTEM maximum lysis < 8%). INTERVENTIONS: Catheter-directed tPA angiography and iFlow system analysis to assess pre-tPA baseline pulmonary perfusion and changes in response to thrombolysis. RESULTS: Nine patients had microvascular filling defects demonstrated by angiography, and good agreement was found with iFlow analysis (ƙ = 0.714). Statistically significant differences were identified in the area under the curve (AUC) region of interest/AUC reference tissue with and without filling defects in phase 2 DM –0.09206 (sd ± 0.16684) (p = 0.003). The Pao2/Fio2 values measured immediately and 48 hours after the procedure were significantly higher (p = 0.001 and p = 0.005, respectively). Statistically significant differences were found in d-dimer values (p = 0.007), Fio2 (p = 0.002), and oxygen saturation in arterial blood/Fio2 (p = 0.045), as well as in the number of patients who required prone positioning before, immediately after the procedure, and at 48 hours after the procedure (p = 0.002). CONCLUSIONS: Thrombolysis with catheter-directed tPA resulted in imaging evidence via pulmonary angiography and iFlow technology of improved lung perfusion in COVID-19 patients with severe respiratory failure.