The Application Value Of Fluorescein Sodium Combined With Contrast Enhanced Ultrasound In Resection Of Contrast Enhancing Gliomas

Objective:To investigate the application value of Fluorescein Sodium combined with Contrast Enhanced Ultrasound in resection of Contrast Enhancing Gliomas. Method:(1) Grouping method: From June 2014 to July 2015, patients with suspected contrast enhancing gliomas while amenable to complete resection were enrolled in our study after screening. Patients were randomly divided into study group and control group. In study group, all the patients underwent surgery by the guidance of fluorescein sodium combined with contrast enhanced ultrasound. In control group, all the patients underwent traditional microsurgical resection. If the pathology turn out to be neoplasms other than glioma or inconsistent with other enrollment conditions, this patient should be excluded.(2) Experimental method: In study group, after patients were intubated under general anesthesia, fluorescein sodium was injected intravenously(4mg/kg), approximately 1.5 h before dural opening. After bone flap removal and prior to dural opening, Contrast Enhanced Ultrasound was used to detect the tumor position, tumor boundary and blood supply condition. Besides, in order to facilitate transcortical approach, it was used to measure the lesion size and the distance to the brain surface. After that, tumor resection was performed under the guidance of fluorescence. During the surgery, the light would be switched between white light and fluorescence model as needed. At the early stage of tumor resection, we took biopsies at the tumor margins when it was suspected and recorded the colour of biopsies under the fluorescent module of microscope, approximately 3 biopsies per patient. These biopsies were defined as A group. After solid tumor was being removed, we executed contrast enhanced ultrasound for the second time to observe the enhancing condition of tumor cavity. Subsequently, we took two biopsies in each patient which were suspected at tumor cavity, and recorded the results of each biopsy under both methods separately. These biopsies were defined as B group. In control group, the surgery was proceeded according to traditional method in the white light of microscope. Besides, we took one biopsy in each patient to clear it’s pathology.All patients were submitted to contrast MRI within 72 h after surgery to compare gross total resection rate between control group and study group. In study group, hepatic and renal functions were examined in three consecutive days after surgery.(3) Observation target: a. Sensitivity and specificity of each method. b. Ability of each method to identify tumor remnants. c. Gross total resection rate. d. The occurrence of adverse reactions in perioperative and test results. Result:1. A total of 26 patients were enrolled into study group, among which 22 patients turned out to be eligible. While in control group, 20 out of 25 patients were eventually confirmed.2. In study group, we got 110 biopsies from 22 patients. In A group, we got 66 biopsies, while in B group we got 44. In A group, the sensitivity and specificity of fluorescein sodium to tumor margin are 88.9% and 100%. In B group, the sensitivity and specificity of fluorescein sodium to tumor margin are 63.6% and 100%. The sensitivity and specificity of contrast enhanced ultrasound to tumor margin are 81.8% and 100%. The comparison of fluorescein sodium’s sensitivity between A group and B group had significant difference(P<0.01). The comparison of sensitivity between fluorescein sodium and contrast enhanced ultrasound in B group did not have statistics difference(p>0.05).3. Among 22 patients in study group, contrast enhanced ultrasound positive tumor remnants which neglected by fluorescein sodium were found in 6 patients(27.3%), and fluorescent tumor remnants which missed by contrast enhanced ultrasound were found in 2 patients(9.1%). In addition, fluorescent tumor remnants covered by non-pathological tissue were discovered in 3 patients(13.6%)using contrast enhanced ultrasound.4. In study group, 20 patients got gross total resection(91%), while the number is 11 in study group(55%). Significant differences of GTR rates were observed between the two groups.(P<0.01)5. No adverse reaction of imaging agent was found through the study and the test results were normal. Conclusion:1. The application of fluorescein sodium can provide real-time information of the suspected tumors conveniently, while Contrast Enhanced Ultrasound can improve the awareness of stereoscopic relationship between tumor and surrounded tissues, and may found concealed tumor in some cases.2. Both fluorescein sodium and contrast enhanced ultrasound have a good specificity to tumor margin, but the sensitivity of fluorescein sodium to tumor margin will decline as the time goes by. The application of fluorescein sodium combined with contrast enhanced ultrasound is a good compensation. This combined method can find additional tumors otherwise missed by single method and make the tumor resection more thorough.3. The application of fluorescein sodium combined with contrast enhanced ultrasound is safe and can significantly improve the GTR rate in comparison with traditional microsurgical resection in contrast enhancing gliomas.