This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Trauma of Nose and Face, Subject name: ENT
[{'content': 'Halo sign and handkerchief test are positive in- \nSelect and explain. \nA. CSF Rhinorrhoea, B. Deviated nasal septum, C. Nasal Myiasis, D. Choanal atresia', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., CSF Rhinorrhoea Detection of CSF Leak in CSF Rhinorrhoea1) Biochemical testso Concentrations of Glucose are higher in CSF than in nasal discharge. Glucose value > 30-40 mg% protein value <100 mg % (max 200 mg %) support a diagnosis of CSF leako Presence of b2 transferrin is the most definitive test for detection of CSF and b2 transferrin assay is the test of choice when a confirmatory test is needed, because of high sensitivity as well as specificity.o b-trace protein (prostaglandin D synthase) is also used, however it is nonspecific as it is also present in human testes, heart and seroma.2) Basic clinical testso Tissue test (Handker chief test):- Unlike nasal mucous, CSF does not cause a tissue to stiffeno Filter paper test:- Sample of nasal discharge on a filter paper exhibits a light CSF border and a dark central area of blood, i.e., double ring sign or halo sign.o Queckensted test:- Compression of the jugular vein leas to increased CSF leak due to increase in ICPo Rhinoscopy:- Visualization of CSF leak from paranasal sinus.3) CSF tracerso Intrathecal fluorescein dye adminstration, radionuclide cisternography, CT cisternography.", 'role': 'assistant'}]