Chapter 109: Conservation Laryngeal Surgery

Question 1

Most common site of invasion of thyroid cartilage:

Answer 1

ANGLE.

Other sites of invasion:

1. points of attachment of the cricothyroid membrane
2. anterior origin of the thyroarytenoid musculature

Question 2

Methods by which ossified bone is infiltrated by cancer: (3)

Answer 2

1. osteoclast formation

2. extension along collagen bundles or through areas of high vascularity

Question 3

Nakayama
and Brandenburgnoted that a large proportion of patients
staged clinically as T3 actually had thyroid cartilage invasion
when the specimens were analyzed by whole-organ sectioning,
and they noted that in these patients with T3 glottic cancers,
any combination of two factors—
_________,
_________
_________

including—resulted in a
higher incidence of cartilage invasion (71% to 92%).

Answer 3

a significant degree
of calcification of the cartilage

tumor length greater than
2 cm

anterior commissure involvement

Question 4

TUMOR SPREAD:

The most common site of cricoid cartilage invasion by carcinoma
is at its _________, and

the most common
site of arytenoid invasion is at the

__________

Answer 4

CRICOID: posterior superior border

ARYTENOID INVASIONS:
points of attachment of the
joint capsule.

Question 5

Most inferior point of the epiglottis is called the ______

Answer 5

petiole

Question 6

Conus elasticus:

1. boundaries/ attachments
2. function, with caveat

Answer 6

1. spans from each VOCAL CORD down LATERALLY to the CRICOID; posteriorly, it is also attached to the ARYTENOID
2. temporary barrier for spread of early glottic CA, but serves as gateway to subglottic and extralaryngeal spread of CA for larger tumors; provides stability to the arytenoid and vocal tendon.

Question 7

Condensations of the conus elasticus:

1. inferiorly
2. superiorly

Answer 7

1. inferiorly - cricothyroid ligament
2. superiorly: thyrohyoid membrane

Anteriorly, a superior inferior condensation of the conus
elasticus, called the cricothyroid ligament, is a central structure
that does not spread out laterally to provide a connective tissue
barrier along the circumference of the cricoid
This is differ
ent
than its superior counterpart, the thyrohyoid membrane,
which drapes along the entire circumference of the thyroid
cartilage superiorly and spreads upward to the hyoid bone

Question 8

Quadrangular Membrane boundaries/extensions:

Answer 8

Anteriorly: Lateral Aspect of epiglottis

Posteriorly: Top of arytenoid

Inferiorly: inferior condensation of fibrous tissue which spans between the INFERIOR aspect of the ARYTENOID posteriorly and the PETIOLE of the epiglottis anteriorly

Question 9

This ligament is a resilient barrier to malignant spread from the supraglottis to the tongue base, when the cancer is confined to the laryngeal membranes and does not clinically invade the suprahyoid epiglottis.

Answer 9

Hyoepiglottic ligament

Question 10

Boundaries of the pre - epiglottic space:

Answer 10

Anterior: thyroid cartilage, thyrohyoid membrane

Posteriorly: Epiglottic cartilage

Superiorly: Hyoid bone, vallecular mucosa

Posterolaterally: superior portions of the paraglottic space

Question 11

Paraglottic space boundaries:

Answer 11

Superiorly, the medial boundary is the quadrangular
membrane, whereas inferiorly, the medial margin is the conus
elasticus. It originates superiorly within the aryepiglottic fold,
where it fades to a peak. The paraglottic space makes up the
substance of the true and false cords, and within it are the
thyroarytenoid musculature and the mucosa-lined, air-filled
space known as the ventricle and its superior extension, the
saccule. Inferiorly, it follows the conus elasticus down to the top
of the cricoid cartilage; anteriorly, it abuts the preepiglottic
space and the anterior third of the thyroid cartilage; and the
posterolateral boundary is the mucosa of the medial aspect of
the piriform sinus. The paraglottic space traverses the supraglottis,
glottis, and subglottis laterally within the larynx. Rather
than having a distinct barrier to superior-inferior spread, cancer
seems to be impeded in its course through the paraglottic space
to varying degrees by the hourglass shape of the space, which
is made by the indentation of the ventricle and saccule.

Question 12

Area where carcinomas at the glottic level tend to begin:

Answer 12

junction of the anterior one third and posterior two thirds of the vocal cord

Question 13

Sensory innervation of RLN is at this area:

Sensory innervation of SLN is at this area:

Answer 13

RLN: Glottis, subglottis

SLN: Supraglottis

Question 14

Respiratory airway: (which part of the larynx)

Phonatory airway:

Answer 14

Respiratory: posterior

ANTerior: phoNATory