Development of a standardized method for contouring the larynx and its substructures

Table 3 CT-based larynx OAR volumes for 44 additional patients with locally advanced head and neck cancer

		p value
Organ at risk	Mean ± SD	CT_{44 pts}–CT_{5 pts}*	CT_{44 pts}–MRI_{5 pts}*
Thyroid cartilage, cm³	10.2 ± 3.11	0.26	0.21
Cricoid cartilage, cm³	3.83 ± 1.29	0.93	0.99
Arytenoid cartilages, cm³	1.00 ± 0.39	0.55	0.52
Suprahyoid epiglottis, cm³	1.94 ± 0.86	0.67	0.83
Infrahyoid epiglottis, cm³	0.96 ± 0.51	0.99	0.61
Epiglottis, cm³	2.91 ± 1.09	0.73	0.59
Aryepiglottic folds/false vocal folds, cm³	6.11 ± 1.72	0.32	0.29
Supraglottic larynx, cm³	13.87 ± 3.68	0.56	0.36
Glottic larynx, cm³	2.99 ± 0.70	0.64	0.44
Subglottic larynx, cm³	5.55 ± 1.94	0.52	0.66
Larynx, cm³	37.20 ± 9.20	0.53	0.62

Abbreviations: OAR = organ at risk; SD = standard deviation; CT = computed tomography-based volumes; MRI = magnetic resonance imaging-based volumes; pts = patients.
*Comparisons are between volumes obtained from 44 additional patients and five initial patients.