Diagnostic tests for disorders of the nose, ear, throat, and cancer play a vital role in early detection, accurate diagnosis, treatment planning, and evaluation of prognosis in medical surgical nursing. Nurses are actively involved in preparing patients, assisting during procedures, monitoring for complications, and providing post-diagnostic care. For disorders of the nose, diagnostic evaluation begins with detailed history taking and physical examination. Anterior and posterior rhinoscopy are commonly performed to visualize the nasal cavity, septum, turbinates, and presence of polyps, infection, or foreign bodies. Nasal endoscopy using a flexible fiber-optic scope provides detailed visualization of deeper nasal structures and sinuses. Imaging studies such as X-ray of paranasal sinuses, computed tomography (CT) scan, and magnetic resonance imaging (MRI) help identify sinusitis, deviated septum, tumors, or fractures. Nasal swab and culture tests are performed to detect bacterial or fungal infections. Allergy testing, including skin prick tests and serum IgE levels, is useful in allergic rhinitis. In suspected malignancy, biopsy of suspicious lesions is essential for histopathological confirmation. For ear disorders, otoscopic examination is the primary diagnostic tool to assess the external auditory canal and tympanic membrane. Tuning fork tests such as