Laryngoscopy
Laryngoscopy is a medical procedure used to visually examine the voice box, or larynx, utilizing either a long-handled mirror or a specialized instrument known as a laryngoscope. This examination can be performed indirectly, requiring minimal patient preparation, or directly, which typically necessitates anesthesia and fasting prior to the procedure. Commonly conducted to diagnose or treat conditions like laryngeal cancer, laryngoscopy can also involve biopsy and surgical interventions depending on the findings.
During the procedure, a topical anesthetic may be applied to the throat or tongue to minimize discomfort. Following laryngoscopy, patients may experience temporary side effects such as a sore throat or hoarseness, particularly if a biopsy or surgical procedure was performed. While laryngoscopy is generally safe, potential risks include excessive swelling or spasms of the larynx, which require immediate medical attention. Results from the examination can reveal normal vocal cord function or indicate abnormalities, such as lesions that may warrant further investigation for cancer. Overall, laryngoscopy plays a crucial role in the diagnosis and management of voice and throat disorders.
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Subject Terms
Laryngoscopy
ALSO KNOWN AS: Autoscopy, laryngeal endoscopy
DEFINITION: Laryngoscopy is the visual examination of the voice box (larynx) using a long-handled mirror or rigid or flexible tube (indirect) or a laryngoscope (direct).
Cancers diagnosed or treated: Cancer of the larynx
Why performed: Indirect and direct laryngoscopy are both diagnostic. Direct laryngoscopy is used for close-up, comprehensive examination, biopsy, and surgery.
Patient preparation: Indirect laryngoscopy is performed in the doctor’s office and requires no preparation. Patients must remove dentures just before the examination. Direct laryngoscopy is performed under anesthesia, so the patient must not eat or drink for several hours beforehand. Blood tests may be required several days before the procedure to confirm that anesthesia poses no risk.
Steps of the procedure: For indirect laryngoscopy, the patient sits facing the physician. The physician sprays a topical anesthetic on the patient’s tongue and throat prior to inserting the mirror or rigid telescope into the mouth. If a flexible fiber-optic tube is used for viewing, then the nose is sprayed with topical anesthetic/decongestant before the physician threads the tube through a nostril and into the throat.
In direct laryngoscopy, the patient is anesthetized, and lies face up to allow the insertion of a laryngoscope into the throat. Anesthesia is delivered via a line inserted into a vein. The throat and larynx are sprayed with topical anesthetic prior to the insertion of a small breathing tube, followed by the laryngoscope.
After the procedure: Laryngoscopy is usually performed on an outpatient basis. However, an overnight hospital stay may be necessary if extensive surgery is also performed. Patients with biopsy or surgery with laryngoscopy may experience hoarseness, and slight bleeding is normal. After surgery, patients should rest their voices and avoid smoking, coughing, or throat clearing.
Risks: Laryngoscopy is a generally safe procedure. Rare complications of direct laryngoscopy are excessive swelling or spasms of the larynx, which are medical emergencies if breathing is hindered. The most common side effects caused by laryngoscope insertion are sore throat, gums, lips, or tongue. Tongue numbness may occur, but the feeling usually returns in a few weeks. Rarely, the introduction of the laryngoscope may chip a tooth.
Results: Normal vocal cords are symmetrical and move freely. If cancer is present, cord movement may be reduced or absent on one side, or cords may appear asymmetrical. Normal tissues appear pink and smooth. Raised, irregular white or red lesions or ulcerated bleeding masses are suspicious. Biopsy and pathology are necessary to determine whether lesions are cancerous.
Bibliography
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