The document describes the different levels and boundaries of the larynx. It defines the supraglottic region as extending from the tip of the epiglottis to the laryngeal ventricle. The glottis extends from the ventricle to 1 cm below the true vocal cords. The subglottic region extends from the true vocal cords to the inferior portion of the cricoid cartilage. It also provides details on the structures within each region such as the false vocal cords in the supraglottis and the true vocal cords in the glottis.

1. LEVELS OF THE LARYNX AND THEIR BOUNDARIES
The supraglottic division:
From the superior-most tip of the epiglottis -to a
transverse plane through the laryngeal ventricle.
 The glottis:
From this transverse plane to 1 cm inferiorly and
includes the true vocal cords.
 The subglottic region
From the inferior-most plane of the true cords -to the
inferior portion of the cricoid cartilage.

3. Supraglottis
• Extends from tip of epiglottis above to
laryngeal ventricle below.
• Contains vestibule, epiglottis, pre-epiglottic
fat, AE folds, FVC, paraglottic space, arytenoid
cartilages

4. • Pre-epiglottic space: Fat-filled space between
hyoid bone anteriorly & epiglottis posteriorly
• AE folds: Projects from cephalad tip of
arytenoid cartilages to inferolateral margin of
epiglottis
• Represents superolateral margin of
supraglottis, dividing it from pyriform sinus
(hypopharynx)

5. • False vocal cords: Mucosal surfaces of laryngeal
vestibule of supraglottis.
• Beneath FVC are paired paraglottic spaces
• Paraglottic spaces: Paired fatty regions beneath
false & true vocal cords
• Superiorly they merge into pre-epiglottic space
• Terminates inferiorly at under surface of TVC

9. Glottis
• TVC & anterior & posterior commissures
• Comprised of thyroarytenoid muscle (medial
fibers are "vocalis muscle")
• Anterior commissure: Midline, anterior
meeting point of TVC

12. Subglottis
• Subglottis extends from under surface of TVC
to inferior surface of cricoid cartilage
• Mucosal surface of subglottic area is closely
applied to cricoid cartilage
• Conus elasticus: Fibroelastic membrane
extends from medial margin of TVC above to
cricoid below

32. CASE 1
Dr. Mohit Goel
JR III

33. NAME : Mr. Harnapallu Baburao Abbanna Req No : 330
Patient Code : 140102135 CT No:330
AGE/SEX : 74 Yr(s) / Male Date: 09/05/2014
MSCT NECK WITH CONTRAST
HISTORY :
K/C/O CA hypopharynx.
Post radiotherapy status,

34. soft tissue density mass involving hypopharynx, larynx & upper oesophagus which is occluding
the laryngeal airway (supra-glottic space) as well as upper end of oesophagus.

35. soft tissue density mass is showing heterogenous post-contrast enhancement.

36. Valecula appears nomral.
Thyroid cartilage appears normal.

37. There is involvement of both thyro-arytenoid folds causing obliteration of both pyriform
sinuses (L>R)

38. Pre-epiglottic space appears normal.
There is involvement of para-glottic space on both sides.

39. Inferiroly the mass is extending upto the level of vocal cords.

40. NAME : Mr. Khan Ibrahim Amir Req No : 339
Patient Code : 140403479 / IPD CT No:339
AGE/SEX : 72 Yr(s) / Male Date: 10/05/2014
MSCT NECK /LARYNX
Clinical Profile: H/o change in voice.

41. Small mildly heterogeneously enhancing polypoidal mass lesion is noted involving right vocal
cord and right para-glottic space, protruding into the laryngeal lumen
Plain Post-contrast

42. There is small non enhancing hypodense area noted within the lesion s/o necrosis.

43. Anteriorly the lesion is extending upto the anterior commissure with minimal extension to
contralateral side. Thyroid cartilage appears normal.

44. There is minimal extension of the enhancing soft tissue into the subglottic region noted at
the anterior commissure. No obvious mass or thickening noted in posterior commissure.

45. Mucosal thickening in ethmoid sinus and right maxillary sinus.

46. Small lymph nodes noted in right level II

47. Calcified atherosclerotic changes are noted.

48. Supraglottic SCC
Approximately 30% of all laryngeal cancers arise in the supraglottis.
They often present in advanced stages, because symptoms
(hoarseness, due to vocal cord involvement) do not occur until late.
Due to the rich lymphatic network of the supraglottis, nodal
disease (level II and III) is a frequent finding in these patients.
Supraglottic SCC may arise in the
• anterior compartment (epiglottis) or
• the postero-lateral compartment (aryepiglottic fold and false
cords).

49. a. Epiglottic SCC
Spread:
PES (Pre-epiglottic space)
Vallecula
base of tongue
PGS (Paraglottic space)
PES glottis or subglottis

51. b. Aryepiglottic fold (AE fold) SCC

52. c. False cord SCC

53. Glottic SCC
Glottic SCCs represent about 65% of all laryngeal cancers.
Hoarseness of voice due to vocal cord involvement is the primary presenting
symptom in these patients.
Metastatic nodal disease is rare in glottic carcinomas due to the sparse lymphatic
drainage of the glottis.
Glottic SCCs commonly arise from the anterior half of the vocal cord and spread
into the anterior commissure.
Anterior commissural disease is seen on CT or MRI as soft tissue thickening of
more than 1-2 mm.

54. Spread to :
• contralateral cord
• thyroid cartilage
• posterior commissure
• Arytenoids
• cricoarytenoid joint and the cricoid cartilage
• superiorly to access the PES and the PGS
• inferiorly to reach the subglottis

56. Subglottic SCC
These cancers are rare, accounting for only 5% of all laryngeal cancers, clinically
silent and present late in the course.
Subglottic cancer is diagnosed if any tissue thickening is noted between the airway
and the cricoid ring.

58. Transglottic SCC
Laryngeal SCC encroaching on both, the glottis and supraglottis, with or without
subglottic component and when the site of origin is unclear, is termed as
transglottic tumor.

59. CORONAL

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