A disorder in which a furrow or groove is seen on the vocal cord, running parallel to, and at or just below, the cord’s free margin. This glottic furrow normally represents a defect in the underlying vocal ligament. Often, the deepest part of the furrow is lined with epithelium that is attached directly to thinned vocal ligament. Pseudobowing (due to mucosal and ligament abnormality more than atrophic muscle) is also a common feature.
Glottic furrow vs. glottic sulcus
A furrow is to be distinguished from a sulcus, which is more a defect within the mucosal layer only, and is thought to represent the empty sac of what was formerly a cyst. A furrow is typically shallow, and its lips are apart; a sulcus is usually deeper, and its lips are in contact and therefore harder to see. A furrow normally adheres to the vocal ligament, and the apex or deep surface of a sulcus often does as well. However, in the case of a sulcus, the vocal ligament itself is normal. Also, in the case of a furrow, the mucosal layer—often only an epithelial layer, in fact—will tend to adhere more broadly to the ligament, due to loss of the Reinke’s space layer of the mucosa.
Glottic furrow (1 of 4)
Congenital furrows, on both vocal cords, in a 14-year-old with lifelong husky, air-wasting voice. Seen here at a distance, under standard light, with cords in breathing position. The margin of each cord, especially that of the left cord (right of photo), has a "flattened" appearance.
Glottic furrow (2 of 4)
As the cords come nearly to phonatory position, notice the pseudo-bowing, and persistence of flattening or even "farmer's field" furrow.
Glottic furrow (3 of 4)
Phonation, open phase of vibration, under strobe light, shows large amplitude (lateral or outward excursions) and, at each line of arrows, an "edge" of mucosa. This edge is seen because the mucosa of the broad expanse of the free margin is closely adherent and cannot oscillate.
Glottic furrow / Leukoplakia / Acid reflux (1 of 4)
Panoramic view, standard light. Note general inflammatory appearance, left vocal cord leukoplakia, interarytenoid pachyderma. Some would call this a sulcus.
Glottic furrow / Leukoplakia / Acid reflux (2 of 4)
Furrow-like groove best seen on the left vocal cord (arrow). Beneath the arrow is the leukoplakia. Notice loss of fine surface vessels in this area.
Glottic sulcus and glottic furrow (1 of 4)
This patient has a glottic sulcus on the left vocal cord (right of image) and a glottic furrow on the right vocal cord.
Glottic sulcus and glottic furrow (2 of 4)
Same patient, inspiratory (breathing in) phonation. Note how this accentuates the opening of the sulcus on the left vocal cord (right of image).
Glottic sulcus and glottic furrow (3 of 4)
Same patient. Compare with photo 4 to observe the vibratory appearance of the sulcus and furrow.
Glottic furrow, showing adherent furrow muscoa (1 of 4)
Standard light showing partially abducted cords. Here, the furrow on the right cord (left of photo) is seen best.
Glottic furrow, showing adherent furrow muscoa (2 of 4)
Closer view, now showing the bilateral glottic furrows more clearly (indicated by the dotted lines).
Glottic furrow, showing adherent furrow muscoa (3 of 4)
Under strobe light, closed phase of vibration. Focus on the right cord (left of photo), and note that the dotted line shows medial oscillatory position of mobile mucosa. The small elevation indicated by the large dot is a reference for comparison with next photo.
Glottic furrow, showing adherent furrow muscoa (4 of 4)
Open phase of vibration. The mucosal wave is very far lateral on the upper surface of the vocal cord, indicated now by the curved dotted line. The small elevation has barely lateralized, consistent with the adherent stiff mucosa of the furrow itself.
Glottic furrow (1 of 4)
This man has performed intense popular music for many years, and has developed loss of strength and clarity of voice. Here, the tiny dots outline bilateral glottic furrows, where the epithelium is more closely adherent to the vocal ligament than it is elsewhere.
Strobe light (2 of 4)
This view under strobe light shows the right-sided furrow enclosed by tiny dots.
High pitch (3 of 4)
At very high pitch under strobe light, vocal cord margins match well; the cause of this man's hoarseness is not a typical vibratory injury such as nodules or a polyp.
Intubation injury (3 of 4)
As the vocal cords begin to close, this view (deep into the posterior commissure) shows clearly the divots caused by pressure necrosis outline where the breathing tube sat. Dotted lines show what would be the normal line of posterior vocal cords.
Phonatory position (4 of 4)
Now in closed voice-making position, posterior defect is out of view, but the vocal processes remain visible and come into contact at arrows. This shows that the endotracheal tube injuries are divots only without scarring of the joint capsules (that if present would prohibit contact of the vocal processes at arrows). There is air wasting through the posterior keyhole not visible here, and the bilateral glottic furrows and pseudo-bowing are extremely evident. They cause additional air-wasting, and adherence of mucosa at the depth of the furrows interferes with the mucosa’s vibratory ability.
Intubation injury + glottic furrows (1 of 4)
Extremely poor voice in elderly man after severe, life-threatening illness with complications; including an 18-day endotracheal intubation for purposes of ventilation. Now he is being evaluated for his very poor voice. Here, open (breathing) position at a distance does not show the findings as clearly as in subsequent photos. Small X's are for reference with remaining photos. The arrows denote tip of vocal processes.
Huskiness (1 of 4)
Huskiness in the context of the series title. Subtle "depressions" in the area outlined become more obvious in the following photos.
Pre-phonatory view (2 of 4)
As the vocal cords come slightly towards each other in preparation to make voice, the depressions are a little more evident.
Bowing vocal cords with furrows (1 of 4)
This middle-aged man's voice has become increasingly husky and weak across many years. In retrospect, it was never a "strong" voice. The cords are bowed, and the furrows seen here (arrows) become more visible in subsequent photos.
"Closed" phase (2 of 4)
Under strobe light at B-flat 2 (117 Hz), this is the "closed" phase of vibration, perhaps better defined in this instance as the "most closed" phase.
Open phase (3 of 4)
The open phase at the same pitch, shows a linear groove just below the margin of each cord. Some might call these glottic sulci, but "furrow" would be the better definition, as seen in the next photo.