The saline challenge‐A test of injection laryngoplasty outcome

Injection laryngoplasty (IL) was first introduced in 1911 by Bruening when he developed a syringe to inject paraffin wax into a paralyzed vocal fold. In 1955, Arnold reintroduced the technique when he injected cartilage into the thyroarytenoid muscle, and soon a variety of materials were used for injection including bone paste, tantalum, silicon, and Teflon paste, the latter of which became popular between the late 1960s and early 1990s but fell out of favor due to foreign body reactions. Bovine collagen was later used, but concerns over hypersensitivity reactions led researchers to purify human forms of collagen. Next, cadaveric dermal tissue and lipoinjection became popular, and hyaluronic gels and calcium hydroxylapatite are currently accepted as widely used today. Diverging from the original indication, IL is now performed for a myriad of etiologies that result in glottic incompetence. Symptoms of glottal incompetence may include ineffective cough, breathy hoarseness, increased phonatory effort/strain, and inability to perform tasks that require positive pressure generation (i.e., heavy lifting). Significantly impaired glottal closure can lead to aspiration and predispose to pneumonia. Glottal incompetence can be due to altered vocal fold mobility, decreased vocal fold bulk, or both. Management aims primarily to medialize the impaired vocal fold to achieve contact with its contralateral counterpart. As the impaired vocal fold usually has a well-maintained vocal fold cover, this treatment can result in significant vocal improvement. For those patients who do not have an adequately mobile vocal fold cover, medialization aims to improve their symptoms that result from lack of sphincteric glottic closure (such as coughing, swallowing, and Valsalva maneuvers). Although a myriad of injectable materials exist, appropriate selection is primarily governed by predicted spontaneous recovery from glottic insufficiency and resultant necessary duration of effect. However, when individualizing care, the outcomes of IL may be difficult to predict and may result in worsening of a preexisting respiratory compromise. As such, the harm–benefit ratio of IL can be difficult to calculate in those patients. The purpose of this report was to demonstrate how saline, a cheap, ubiquitous, and ultra–short-acting injectable material, can be used to assess IL outcome. Furthermore, we define the patient populations for which this diagnostic step is most beneficial.