Table 4.

Studies assessing dose–volume analyses for late dysphagia

Study	Patients	Site	Dosimetric factors correlated with late dysphagia	Limits	Anatomical borders
					SPC	MPC	IPC	Crico
Feng34	36	OP/NP	PCs (mean dose, V50, V60, V65)	Cranial Caudal	Caudal tips of pterygoid plates Upper edge hyoid bone	Upper edge of the hyoid bone Lower edge of the hyoid bone	Below the hyoid bone Inferior edge of the cricoid	Not mentioned Not mentioned
Levendag21	56	OP	SPC, MPC (mean dose)	Cranial Caudal	Mild C2 Upper C3	Upper C3 Upper C4	Upper C5 Mid C6	Mild C6 First ring of trachea
Jensen35	25	PH	SL (mean dose, V60, V65)	Cranial Caudal	Lower part transverse process C2 Top of cricoid cartilage	Lower part transverse process C2 Top of cricoid cartilage	Lower part transverse process C2 Top of cricoid cartilage	Not mentioned Not mentioned
Caglar29	96	M	IPC (mean dose, V50, V60)	Cranial Caudal	Pterygoid plates Upper edge of the hyoid bone	Upper edge of the hyoid bone Lower edge of the hyoid bone	Inferior edge hyoid bone Lower edge cricoid	Not mentioned Not mentioned
Dirix30	53	M	MPC (mean dose,V50)	Cranial Caudal	Caudal tip of the pterygoid plates Upper edge hyoid bone	Upper edge of the hyoid bone Lower edge of the hyoid bone	Inferior edge hyoid bone Lower edge cricoid	Lower edge cricoid Upper edge of trachea
Bhide31	37	M	No correlations	Cranial Caudal	Base of the skull Superior end hyoid bone	Superior end of the hyoid bone Caudal end of the cartilage cricoid	Inferior edge hyoid bone Lower edge cricoid	Not mentioned Not mentioned
Caudell36	83	M	IPC (V60, V65)	Cranial Caudal	Pterygoid plates Upper edge of the hyoid bone	Upper edge of the hyoid bone Lower edge of the hyoid bone	Inferior edge hyoid bone Lower edge cricoid	Not mentioned Not mentioned
Mortensen32	65	M	SPC, MPC (mean dose)	Cranial Caudal	Caudal tip of the pterygoid plates Lower edge of C2	Upper edge of C3 Lower edge of hyoid bone	First slice caudal to the lower edge of hyoid bone Lower edge of the arytenoid cartilages	First slice caudal to the arytenoid cartilages Lower edge of the cricoid cartilages
Current study	56	M	SPC (Dmax <60,V50	Cranial Caudal	Caudal tip of the pterygoid plates Lower edge of C2	Upper edge of C3 Lower edge of hyoid bone	First slice caudal to the lower edge of hyoid bone Lower edge of the arytenoid cartilages	First slice caudal to the arytenoid cartilages Lower edge of the cricoid cartilages

C2, second cervical vertebra; C3, third cervical vertebra; C4, fourth cervical vertebra; C5, fifth cervical vertebra; C6, sixth cervical vertebra; Crico, cricopharyngeal muscle; D60, minimum dose received by 60% of a structure; D_max, dose maximum; IPC, inferior constrictor muscle; M, miscellaneous; MPC, middle constrictor muscle; NP, nasopharynx; OP, oropharynx; PCs, all constrictors; PCS, pharyngeal constrictor muscle; PH, pharynx; SL, supraglottic larynx; SPC, superior constrictor muscle; V50, volume of a structure receiving 50 Gy; V60, volume of a structure receiving 60 Gy; V65, volume of a structure receiving 65 Gy; V70, volume of a structure receiving 70 Gy.