[To introduce a new method of resection of carotid body tumor with preservation of the internal carotid artery ----microscopic coagulation method].

Objective:To introduce the surgical experience of carotid body tumor（CBT） resection with preservation of internal carotid artery. Methods:The clinical data of 109 patients with CBT were retrospectively analyzed. The key points of surgical techniques were summarized, the imaging and pathological results were comprehensively analyzed, and the postoperative complications were observed. Results:Of the 109 patients, 28 were Shamblin Ⅰ, 46 were Shamblin Ⅱ, and 35 were Shamblin Ⅲ. Synaptophysin（SYN） and soluble protein-100（S-100） were positive in all cases. There was a positive correlation between the average expression area percentage of S-100 and SYN in pathological tissue of 17 patients（r=0.48）, and the difference was statistically significant（P<0.05）. The average operation time was（148.4±46.2） minutes, the average intraoperative blood loss was（64.7±22.8） mL, and the average hospital stay was（15.2±2.6） days. Three patients underwent tumor resection combined with external carotid artery ligation, 1 patient underwent tumor resection combined with internal carotid artery ligation, and the remaining patients underwent tumor resection alone. The overall rate of intraoperative vascular ligation was 3.7% and the rate of nerve injury was 6.4%. According to preoperative CTA, intraoperative situation and postoperative pathological results, a new classification of CBT was proposed, which could intuitively reflect the gap between the tumor and the carotid artery and the nature of the tumor. Conclusion:Surgical resection of CBT is recommended after diagnosis. The potential gap between the tumor and the blood vessels was found under the microscope. Low energy bipolar electrocoagulation was used to coagulate and cut off the fibrous connective tissue between the tumor and gradually separated along the adventitia of the artery. The carotid artery could be preserved in most cases while the tumor was completely removed, and the amount of intraoperative bleeding and the incidence of complications were reduced. It is particularly important to identify the difficult cases before operation.

Cochlear metabolomics, highlighting novel insights of purine metabolic alterations in age-related hearing loss.

Aging is an inevitable phase in mammals that leads to health impairments, including hearing loss. Age-related hearing loss (AHL) leads to psychosocial problems and cognitive decline in the elderly. In this study, mean thresholds of auditory brainstem responses (ABR) and distortion-product otoacoustic emissions (DPOAE) increased at multiple frequencies in aged rats (14 months old) compared to young rats (2 months old). Using untargeted ultra-high performance liquid chromatography-mass spectroscopy (LC-MS), we quantified molecular metabolic markers in the cochlea of aged rats with hearing loss. A total of 137 different metabolites were identified in two groups, highlighting several prominent metabolic pathways related to purine metabolism; glycine, serine, and threonine metabolism; arginine and proline metabolism; and pyrimidine metabolism. In addition, the beneficial effects of purine supplementation were demonstrated in a mimetic model of senescent marginal cells (MCs). Overall, altered metabolic profiling is both the cause and manifestation of pathology, and our results suggest that cellular senescence and dysfunctional cochlear metabolism may contribute to the progression of AHL. These findings are seminal in elucidating the pathophysiological mechanisms underlying AHL and serve as a basis for future clinical predictions and interventions in AHL.

[Advances in stem cell inner ear transplantation].

Sensorineural hearing loss has long been one of the common diseases in the field of otology. With the increasing research on stem cell therapy, the experiments and applications of stem cell inner ear transplantation are developing rapidly, with some remarkable results and some questions to be considered. The source of stem cells and the transplantation route are crucial, and the immune rejection in the post-transplantation period should not be ignored. This paper will review the issues related to stem cell source, transplantation route and immune rejection in inner ear transplantation, hoping to provide new ideas for research in the field of stem cell inner ear transplantation.