Sulcus Vocalis - Types, Causes, Symptoms, Diagnosis, and Treatment

Introduction:

Vocal folds are the bands of soft tissue lamina surrounding the larynx (voice box). Vocal folds help in the functions like speech, swallowing, and breathing. Sulcus vocalis is a structural deformity affecting the vocal folds by the presence of a groove or depression at the edge of the vocal folds and is also called scarring of the vocal folds. The vocal folds sulcus or scar disrupts the normal functions of the vocal folds, like vibratory function leading to speech dysfunction, hoarseness of voice, and vocal fatigue.

What Is the Prevalence of Sulcus Vocalis?

• The prevalence of sulcus vocalis is around 48.3 percent among patients with larynx cancer.

• Bilateral sulcus vocalis is seen in 25 percent of cases, and unilateral sulcus vocalis is seen in 75 percent of cases of larynx (voice box) cancer.

What Are the Types of Sulcus Vocalis?

There are three types of sulcus vocalis depending on the involvement of the vocal fold muscle:

• Type 1 Physiological Sulcus Vocalis: Type 1 sulcus vocalis appears as a longitudinal groove on the uppermost layer of the vocal fold. It does not affect the vibratory function of the vocal folds. The voice is normal.

• Type 2 Sulcus Vergeture: Type 2 sulcus vocalis has a groove extending more longitudinally involving both superficial and deep layers of the vocal folds but does not involve vocal ligaments that result in mild to severe dysphonia (abnormal voice).

• Type 3 Sulcus Vocalis Proper: Type 3 sulcus vocalis extends deep beyond the vocal ligament involving thyroarytenoid muscle (a broad muscle that forms the body of the vocal fold) resulting in hoarseness, dysphonia, and vocal fatigue.

What Are the Causes of Sulcus Vocalis?

Sulcus vocalis or vocal fold scars are caused due to the following:

• Congenital: It can be present since birth.

• Vocal Abuse: It can be due to excessive use of vocal folds like screaming or yelling.

• Laryngeal Esophageal Reflux: Continuous acid reflux from the stomach to the esophagus can lead to vocal fold damage.

• Infections: Vocal fold lesions involving the ligaments can cause sulcus vocalis

• After Surgery: It can occur after the surgery of the vocal folds due to trauma during the surgery.

• Vocal trauma: Trauma to the vocal cords by direct external injury.

• Radiotherapy: Sulcus vocalis can occur in people who are under radiation therapy for cancer.

What Are the Signs and Symptoms of Sulcus Vocalis?

Signs and symptoms associated with sulcus vocalis are:

• Hoarseness of voice.

• Abnormal speech (Dysphonia).

• Vocal Fatigue (increased effort while speaking).

• Breathlessness while speaking.

• Loss of vocal pitch.

• Loss of vocal tone.

• Complete loss of voice in severe cases.

How To Diagnose Sulcus Vocalis?

Sulcus vocalis is diagnosed by the following methods:

• History and Clinical Examination: The history of the patient for ongoing radiotherapy sessions, past surgery of the larynx, and any recent trauma should be noted. Clinical examination of the vocal folds is done by a laryngoscope (a thin instrument with an attached light on the tip) to rule out any infections or structural defects present in the vocal folds.

• Videostroboscopy: A telescope-like instrument with an attached camera is used to analyze the slow-motion video of the vocal fold vibrations while breathing in and out. Any deformities in vibration or opening and closing of the vocal folds can be detected by using this method.

• Voice Assessment: Assessment of voice is done by the speech-language pathologist to detect loss of vocal tone, vocal pitch, or abnormal voice.

What Is the Treatment of Sulcus Vocalis?

Sulcus vocalis is managed by the following methods :

• Medicinal Therapy: Antacids like proton pump inhibitors to prevent acid reflux, steroids and antibiotics are prescribed as initial management to reduce swelling in the vocal folds due to infections.

• Voice Therapy: Voice therapy sessions are done for the patients under the guidance of speech-language pathologists to treat vocal insufficiency, relax vocal cords and improve the quality of voice.

• Vocal Fold Medialization: It is a surgical procedure done in patients with one (unilateral) vocal cord immobility. In this method, the immobile vocal cord is moved towards the functional vocal folds, which helps in vocal fold closure while speaking, eating, and breathing. The goal of this surgery is to prevent aspiration (leakage) of food contents while swallowing into the windpipe.

• Vocal Fold Augmentation Injections: Vocal fold injections with filler materials like hyaluronic acid (20 milligrams per milliliter), calcium hydroxyapatite, silicon, paraffin, and Teflon are injected into the vocal folds on the lateral surface through transoral (through oral cavity) approach is used to treat sulcus vocalis or vocal fold scars.

• Gray’s Minithyrotomy: It is an open surgical procedure in which a small window (opening) in the thyroid cartilage is made, and a pocket is created in the superficial layer (superficial lamina propria) of the vocal folds to elevate the vocal scar followed by placement of fat or muscle fascia graft in the created pocket. This method improves vocal fold closure, and vocal cord functions and treats vocal fold scars effectively.

• Growth Factor Injections: Hepatocyte and basic fibroblast growth factor injections are used to treat sulcus vocalis.

• Laser Therapy: Sixty to hundred laser pulses (0.75 joules per pulse) is used on each vocal fold to improve mucosal vibration, reduce speech deformities, and vocal cord stiffening.

• Stem Cell Therapy: Stem cell therapy can be used to manage sulcus vocalis by regeneration of the vocal fold tissues. Human mesenchymal stem cells and adipose (fat) derived stem cells can be used in this method.

Conclusion:

Sulcus vocalis is commonly seen in patients with laryngeal cancer. It can involve single or both vocal folds resulting in symptoms like hoarseness of voice, vocal fatigue, changes in vocal pitch or frequency, and complete loss of voice in severe cases. Early diagnosis and management of vocal fold grooves or scars are crucial for preventing the worsening of the symptoms due to sulcus vocalis. However, there are multiple approaches for the treatment of sulcus vocalis like filler injections and stem cell therapy but further research is needed to assess the effectiveness of these treatment approaches in the management of sulcus vocalis and recovery of voice disorder.