ABSTRACT
Abstract Introduction The most common site of salivary gland tumors is the parotid gland. Computed tomography (CT), magnetic resonance imaging (MRI), and sonography are imaging modalities to differentiate benign from malignant parotid tumors. Objective The aim of this study is the evaluation of the diagnostic value of perfusion CT for differentiating histological categorization of benign and malignant parotid tumors. Methods A total of 29 patients with parotid neoplasms were enrolled in this study. Mean age and all CT perfusion variables (gradient and permeability, blood flow[BF], blood volume [BV], mean transit time [MTT], permeability surface [PS], maximum intensity projection [MIP], time-density curve [TDC], and time to peak [TTP]) were compared among three groups (malignant tumors [MTs],Warthin's tumor [WT] and pleomorphic adenomas [PA]). Results The mean age of the patients was 55.9±14.1 (26-77), and 15 of them were male (51.7%). Eleven lesions were PAs [37.9%], 8 lesions were WTs (27.6%0 and 10 lesions (34.5%) were MTs (6 acinic cell carcinomas [ACCs], 3 adenocystic carcinomas [AdCCs], and 1 mucoepidermoid carcinoma [MEC]). The mean age of the patients with WTs was 62±7.5 years; 52±14.2 for patients with Pas, and 55.2±17.2 for those with MTs (p=0.32). The mean MIP was 122.7±12.2 in WT, while it was 80.5±19.5 in PA, and 76.2±27.1 in MTs (p<0.001); The mean MIP for WT was higher than for PAs and MTs; the values of MTs and PAs were not statistically different. The average of BF, BV, and curve peak were higher inWTs in comparison with the other two groups, and curve time 2 and TTP were higher in PAs in comparison with MTs. Conclusion Based on this study, perfusion CT of the parotid gland and its parameters can distinguish between benign and malignant parotid masses.
ABSTRACT
Background and Objective: Metformin (MET) has been used as an antidiabetic agent for type II diabetes. At the same time, recent researches have shown that the clinical improvement of MET is useful for nerve damage. In this study, we investigated the analgesic effect of MET in paclitaxel (PAC)-induced neuropathic pain. Materials and Methods: Forty-two adult, female rats, Wistar strain weighing 220 ± 10 g were randomly divided into 5 experimental groups. PAC was intraperitoneally (IP) administered (2.0 mg/kg) for 4 groups every other day (0, 2, 4, and 6 days). By the 30th day, MET (100, 200, and 400 mg/kg) was administered to 4 groups. Before and after treatment, basal pain threshold values were measured with Randall–Selitto analgesiometer test. At the end of experiment, pathological values were measured in selected regions including brain (motor cortex, M1), spinal cord (L4-L5), sciatic nerve, and muscle. Results: According to our results, PAC-induced neuropathic pain reached to highest level at 14th day. Four hundred milligram/kilogram concentration of MET remarkably decreased PAC-induced neuropathic pain. On the other hand, pathologic features have shown that PAC had significant pathological change in the brain and spinal cord while in the peripheral nerves and muscles had not shown any pathological change. Conclusion: The pathological results of the current study for the first time demonstrated that MET beside of its antidiabetic effects reversed neuropathic pain induced by PAC. Consequently, this research can be promising for cancer patients that suffering from neuropathic pain induced by anticancer drugs.