Table 1.

Triangle description by different authors

Name	Other names	Borders	Content
Oculomotor triangle	Hakuba´s triangle	1.Anterior petroclinoid dural fold	Oculomotor Nerve
Dolenc [5]	Drazin et al. [6]	2. Posterior petroclinoid dural fold	ICA horizontal segment
		3. Interclinoid dural fold	Drazin et al. [6]
	Medial triangle	Drazin et al. [6]
	Drazin et al. [6]
		1. Medial border: A line between the anterior and posterior clinoid process
		2. Lateral border: the fold of the dura between the anterior clinoid process and petrous apex	The site where the oculomotor nerve enters the roof of the cavernous sinus
		3. Base: the fold of the dura from the posterior clinoid process to the petrous apex	Distal intra-cavernous carotid artery
		Isolan et al. [14]	Isolan et al. [15]
		1. Anterior petroclinoid fold: petrous apex to the anterior clinoid process	Cavernous sinus
		2. Posterior petroclinoid fold: petrous apex to the posterior clinoid process	Gallardo et al. [10]
		3. Interclinoid fold: anterior and posterior clinoid process
		Gallardo et al. [10]
Clinoidal triangle	Dolenc´s triangle	1. Optic nerve	Clinoidal internal carotid artery
Isolan et al. [14]	Fujimoto et al. [9]	2. Oculomotor nerve	Anterior clinoid process
		3. Tentorial edge (a line between the dural entry point of the third cranial nerve and the optic nerve)	Drazin et al. [6]
	Anteromedial triangle	Drazin et al. [6]
	Dolenc [5]		Anteriorly: Optic strut
		1. Medial border: optic nerve	Middle: Subclinoidal segment of the ICA
	Anterior triangle	2. Lateral border: third cranial nerve from the entry point in the sinus roof to the point just before entering the superior orbital fissure	Posteriorly: the roof of cavernous sinus (after drilling de anterior clinoid process)
	Gallardo et al. [10]	3. Base: the dura extending between the posterior limits of the medial and lateral border	Isolan et al. [14]
		Isolan et al. [14]
Supratrochlear triangle	Paramedian triangle	1. Medially: oculomotor nerve	Meningohypophyseal trunk, the inferolateral trunk and less commonly the medial loop of the ICA
Isolan et al. [14]	Goel [11]	2. Laterally: trochlear nerve	Drazin et al. [6]
		3. Inferiorly: tentorial edge (the dura extending between the dural entry points of the third and the fourth cranial nerves)
		Watanabe et al. [29]
	Paramedial triangle
	Dolenc [5]	1. Oculomotor nerve
		2. Trochlear nerve
	Superior	3. Tentorial edge
	Fukushima	Drazin et al. [6]
	Wanibuchi [28]
Infratrochlear triangle	Parkinson´s triangle	1. Medially: trochlear nerve	ICA (cavernous) and the abducens nerve
Isolan et al. [14]	Dolenc [5]	2. Laterally: ophthalmic division of the trigeminal nerve
		3. Base: tentorial edge of these two nerves	Drazin et al. [6]
	Superolateral triangle	Watanabe et al. [29]
	Watanabe et al. [29]	1. Trochlear nerve	Posterior–superior, anterior–inferior, and lateral venous spaces and lateral surface of the C5 and C6
		2. Ophthalmic division (V1)	Watanabe et al. [29]
		3. Tentorial edge
		Drazin et al. [6]	Origin of the meningohypophyseal trunk
			Peltier et al. [24]
		1. Superiorly: lower margin of the trochlear nerve
		2. Inferiorly: upper rim of the ophthalmic nerve and of the trigeminal ganglion
		3. Posterior: slope of the dorsum sellae and clivus
		Kayalioglu et al. [17]
Anteromedial triangle	Mullan´s triangle	1. Lower margin of ophthalmic nerve	Sphenoid sinus
Conti et al. [3]	Hakuba et al. [13]	2. Upper margin of maxillary nerve	Granger et al. [12]
		3. Line connecting superior orbital fissure and foramen rotundum
		Granger et al. [12]	Superior orbital fissure artery
	Anterolateral triangle		Conti et al. [3]
	Dolenc [5]	1. Upper margin of maxillary nerve
		2. Line connecting the ophthalmic nerve at superior orbital fissure and the maxillary nerve at foramen rotundum	Pituitary gland
		Rhoton [26]	Watanabe et al. [29]
Anterolateral triangle	Lateral triangle	1. Lower Surface of maxillary nerve	Lateral wing of the sphenoid sinus
Kobayashi [19]	Dolenc [5]	2. Upper surface of the mandibular nerve	Rhoton [26]
		3. Line connecting the foramen ovale and rotundum
	Far Lateral	Rhoton [26]	Lateral wing of the sphenoid sinus
	Day et al. [4]		Vidian nerve
		1. Medial border: Lower surface of the maxillary nerve,	Pterygoid region
	Lateralmost	2. Lateral border: upper surface of the mandibular nerve	Granger et al. [12]
	QuinonesHinojosa [25]	3. Base: a line connecting the foramen ovale and rotundum
		Watanabe et al. [29]
		1. Posterior border: maxillary division of the trigeminal nerve
		2. Anterior border: mandibular division of the trigeminal nerve
		3. Line connecting the foramen rotundum to the foramen ovale
		Granger et al. [12]
Posterolateral Triangle	Glasscock	1. Medial border: Line between where the GSPN crosses under V3 and the foramen spinosum	Posterior and lateral loops of ICA
Dolenc [5]	Dolenc [5]	2. Lateral border: Line between the foramen spinosum and geniculate ganglion	Greater and lesser petrosal nerves
		3. Base: GSPN	Tensor tympani muscle
	Paullus	Isolan et al. [14]	Eustachian tube
	Wanibuchi [28]		Middle meningeal artery
		1. Medial border: a line between the points on the lateral surface of the mandibular nerve where the greater petrosal nerve crosses to the foramen spinosum	Infratemporal fossa
		2. Lateral border: line between the foramen spinosum and the center of the geniculate ganglion	Isolan et al. [14]
		3. Base: medial margin of the greater petrosal nerve
		Watanabe et al. [29]
Posteromedial Triangle	Kawase	1. Medial border: GSPN	Posterior cavernous sinus
Dolenc [5]	Dolenc [5]	2. Lateral border: Line between where the GSPN crosses under V3 and the petrous apex	Entry point to the posterior fossa (anterior petrosectomy)
		3. Base: Line between the crest of the petrous apex to the geniculate ganglion	Lateral apex: Cochlea, anterior wall of the IAC
	Kawase-Shiobara	Watanabe et al. [29]	Anterior margin: Petrous carotid
	Kanzaki		Medial margin: Clivus and inferior petrosal sinus
	Wanibuchi [28]		Isolan et al. [14]
		1. Anterior border: V3
		2. Posterior border: Arcuate Eminence
		3. Lateral border: GSPN
		4. Medial border: Petrous ridge
		Isolan et al. [14]
Paraclival	None	1. Posterior clinoid process	Dorello’s canal and Gruber’s ligament
Inferomedial		2. Dural entrance of the trochlear nerve	Drazin et al. [6]
Dolenc [5]		3. Dural entrance of the abducens nerve
		Isolan et al. [14]	Dura forming the posterior wall of the cavernous sinus, the abducens nerve, the petrosphenoidal (Grüber’s) ligament,
			The posterior genu of the internal carotid artery’s intracavernous segment
		1. Posterior clinoid process	Dorsal meningeal artery
		2. Dural entry of the Trochlear nerve	Wysiadecki et al. [32]
		3. Dural entry of the abducens nerve
		Wysiadecki et al. [32]	The abducens nerve
			the posterior genu of the ICA
		1. Medial: posterior clinoid process	the dorsal meningeal artery
		2. Supero-lateral: Dural entry of the Trochlear nerve	the basilar venous plexus
		3. Inferolateral: Dural entry of the abducens n	the posterior petroclinoid fold
		Dolenc [5]	Isolan et al. [14]
Paraclival	None	1. Medially: by a line between the dural entrance of the trochlear nerve into the tentorium cerebelli to the dural entry of the abducens nerve	Porus trigemini (the Meckel’s cave)
Inferolateral		2. Laterally by a line between the dural entry point of the abducens nerve and the petrosal vein	Drazin et al. [6]
Dolenc [5]		3. Petrous apex
		Drazin et al. [6]
		1. Line between the entry point of CN IV at the tentorium and CN VI at Dorello’s canal	Porus trigeminus
		2. Line between entry point of CN VI at Dorello’s canal and the superior petrosal vein at the superior petrosal sinus	The entrance of the sixth nerve in Dorello’s canal
		3. Line between entry point of CN IV at the tentorium and the superior petrosal vein at the superior petrosal sinus	The fourth cranial nerve entrance along the incisura into the lateral wall of the cavernous sinus
		Isolan et al. [14]	Isolan et al. [14]
		1. Anterior border: line connecting the dural entry point of the trochlear nerve to the dural entry point of the abducens nerve
		2. Posterior border: line connecting the dural entry point of the abducens nerve to the drainage site of the petrosal vein into the superior sagittal sinus
		3. Superior border: line connecting the dural entry point of the trochlear nerve to the petrosal vein
		Kimball et al. [18]